text:
La taula periòdica, taula de Mendeléiev o sistema periòdic dels elements és una taula que ordena els elements químics de menor a major nombre atòmic tot posant de manifest la periodicitat de les seves propietats químiques i físiques. S'hi reflecteix la llei periòdica formulada el 1869 pel químic rus Dmitri Mendeléiev de la Universitat Imperial de Sant Petersburg, això és, la semblança dels elements químics cada cert nombre de nombres atòmics.

Els químics consideren que la taula periòdica constitueix la base i l'eix vertebrador dels seus coneixements i ha esdevingut amb els anys un clar element identificador, un símbol de la química.

L'estructura actual de la taula periòdica de la Unió Internacional de Química Pura i Aplicada (IUPAC) consta de:

 118 caselles, una per a cada element químic. La informació mínima de cada casella és el símbol químic de l'element que l'ocupa i el seu nombre atòmic Z. Sovint també hi figura el nom de l'element i la massa atòmica relativa. Addicionalment s'hi posen dades de propietats atòmiques (radi atòmic, energia de ionització…), físiques (punts de fusió i d'ebullició, densitat…) i químiques (nombre d'oxidació, electrons de valència…).
 7 períodes (fileres) de longituds creixents numerats de l'1 al 7 i començant per la part superior. El 1r període té només dos elements; el 2n i el 3r períodes vuit elements cadascun; el 4t i el 5è devuit cadascun, i els 6è i 7è en tenen cada un trenta-dos. Si se sintetitzen nous elements químics ocuparan el període 8è, ara buit.
 18 grups o famílies (columnes), amb propietats físiques i químiques molt similars. S'anomenen de l'1 al 18 començant per l'esquerra. Alguns grups tenen noms: el grup 1 és el dels alcalins, el 2 dels alcalinoterris, el 16 el dels calcògens, el 17 el grup dels halògens i el 18 el grup dels gasos nobles.
 4 blocs segons les seves configuracions electròniques: el bloc s els formen les dues columnes de l'esquerra (alcalins i alcalinoterris) a més de l'hidrogen i l'heli; bloc p el constitueixen els grups (columnes) del 13 al 18, ubicats a la dreta, excepte l'heli; bloc d ocupa el centre amb els grups del 3 al 12; i el bloc f amb els elements anomenats lantanoides i els actinoides, col·locats en dues files a la part inferior de la taula. L'element 121 obrirà el bloc g.

Gràcies a la distribució de Mendeléiev dels elements químics coneguts a mitjans del , pogué predir l'existència d'elements químics encara no descoberts (gal·li, germani…) i les propietats físiques (punt de fusió, densitat, color…) i químiques (massa atòmica, compostos, reactivitat química amb l'aire, l'aigua, els àcids, les bases…) que tindrien. Foren aïllats pocs anys després (el gal·li el 1875, el germani el 1886…) i confirmaren les prediccions fetes pel químic rus, la qual cosa donà un fort suport a la seva taula periòdica.

Posteriorment, la taula periòdica original s'hagué de modificar per incloure grups d'elements que no havien estat predits (gasos nobles, lantanoides) o que se sintetitzaren car no existeixen a la natura (actinoides), donant lloc a la taula periòdica actual.

Codificació de colors dels nombres atòmics dels elements:
 En blau són líquids a temperatura i pressió estàndard (TPE);
 En verd, són gasos a TPE;
 En negre, són sòlids a TPE;
 En vermell, són sintètics (tots són sòlids a TPE);

Estructura
En la taula periòdica de la Unió Internacional de Química Pura i Aplicada (IUPAC), els elements químics s'ordenen per ordre creixent de nombre atòmic  en files (en horitzontal), començant per la part superior esquerra. S'inicia una nova fila quan els electrons de l'escorça atòmica han completat l'orbital atòmic 1s pel primer període i els orbitals atòmics np amb n = 2, 3,... pels períodes 2, 3,... de manera que els elements que tenen propietats químiques i físiques semblants queden situats en les mateixes columnes (en vertical) perquè tenen configuracions electròniques semblants. És el cas dels gasos nobles, que tots tenen configuració electrònica acabada amb ns^2 np^6, o dels metalls alcalins, que tots tenen estructura electrònica acabada en ns^1.

Files o períodes
Les files d'elements, s'anomenen períodes i n'hi ha set, numerats de l'1 al 7 començant per la part superior. No tots tenen el mateix nombre d'elements: a la part superior el període 1 en té 2, l'hidrogen i l'heli, un a l'esquerra i l'altre a la dreta; els períodes 2 i 3 en tenen 8 cadascun (2 a l'esquerra i sis a la dreta); els períodes 4 i 5 en tenen 18 cadascun; i els períodes 6 i 7 en tenen 32 cadascun. Tanmateix aquest dos darrers períodes tenen 15 elements cadascun (lantanoides i actinoides) que se situen separats a la part inferior, evitant així una taula desmesuradament llarga.

La diferència del nombre d'elements a cada període és degut a la diferent capacitat que tenen els nivells energètics atòmics. A mesura que s'augmenta de nivell energètic s'incrementa la capacitat d'acollir electrons. Així al nivell de nombre quàntic principal n = 1 hi caben 2 electrons; al nivell n = 2, 8 electrons; al nivell n = 3, 18 electrons i al nivell n = 4, 32 electrons.

Si se sintetitzen nous elements, caldrà situar-los en el vuitè període. La IUPAC el 1978 aprovà un sistema de nomenclatura per anomenar provisionalment els nous elements fins que s'aprovi el nom definitiu. Aquests sistema es basa en derivar el nom a partir del nombre atòmic. Els noms provisionals dels deu primers nous elements seran: Uue, ununenni (119); Ubn, unbinili (120); Ubu, unbini (121); Ubb, unbibi (122); Ubt, unbitri (123); Ubq, unbiquadi (124); Ubp, unbipenti (125); Ubh, unbihexi (126); Ubs, unbisepti (127) i Ubo, unbiocti (128).

Columnes o grups

A les columnes, hi queden les famílies o grups d'elements semblants. N'hi ha 18 numerades de l'1 al 18 començant per l'esquerra. Els grups 1, 2, 13, 14, 15, 16, 17 i 18 s'anomenen elements del grups principals, i excepte pel grup 18, els dos primers elements de cada grup principal poden anomenar-se elements típics. La resta d'elements s'anomenen elements de transició. Els grups són:

 A l'esquerra de la taula hi ha dos grups de sis elements cadascun. El grup 1 s'anomena del metalls alcalins, és el primer de l'esquerra i inclou el elements liti, sodi, potassi, rubidi, cesi i franci. El grup 2, dels alcalinoterris, conté el beril·li, el magnesi, el calci, l'estronci, el bari i el radi.
 Al mig hi ha quaranta elements dels grups 3 al 12 s'anomenen metalls de transició; són els elements de l'escandi (21) al zinc (30) o metalls de transició de grup del ferro; de l'itri (39) al cadmi (48), els metalls de transició del grup del pal·ladi; del luteci (71) al mercuri (80), els metalls de transició del grup del platí i el grup d'elements sintètics del lawrenci (103) al copernici (112). La composició del grup 3 és una qüestió no resolta, ja que podria estar format per escandi, itri luteci i lawrenci o, per contra, per escandi, itri, lantani i actini.
 A la dreta hi ha vuit grups de sis elements cadascun: el grup 13 o del bor que conté els elements bor, alumini, gal·li, indi, tal·li i nihoni; el grup 14 o del carboni que, a més del carboni, conté el silici, el germani, l'estany, el plom i el flerovi; el grup 15 o del nitrogen, amb nitrogen, fòsfor, arsènic, antimoni, bismut i moscovi; el grup 16 o dels calcògens (oxigen, sofre, seleni, tel·luri, poloni i livermori); el grup 17 o dels halògens (fluor, clor, brom, iode, àstat i tennes) i el 18 o dels gasos nobles (heli, neó, argó, criptó, xenó, radó i oganessó).
 A la part de sota de la taula hi ha dues sèries horitzontals separades amb quinze elements cadascuna, són el grup dels lantanoides, que va del lantani al luteci; i el grup dels actinoides, de l'actini al lawrenci.

Tot i que l'hidrogen s'inclou en el grup 1 no forma part del grup dels alcalins i podria incloure's en el grup 17 (halògens) malgrat no és gaire semblant ni a uns ni als altres en les seves propietats químiques. No obstant això, se li assigna el nombre d'oxidació +1 en compostos com el fluorur d'hidrogen, HF i −1 en compostos com l'hidrur de liti, LiH; i per tant es pot considerar que és semblant a un element del grup 1 (alcalins) i a un element del grup 17 (halògens), respectivament, en compostos d'aquests dos tipus, prenent el lloc primer de Li i després de F al fluor de liti, LiF. L'hidrogen és, de fet, l'element més singular: cap altre element no s'assembla a ell, de la mateixa manera que el sodi s'assembla al liti, el clor s'assembla al fluor i el neó s'assembla a l'heli. És l'únic element que no es pot considerar convenientment com a membre d'un grup.

Blocs

Una comparació de les configuracions electròniques dels elements amb la taula periòdica revela que cada període comença amb l'addició d'un electró en un nou nivell energètic, no ocupat prèviament. Així, l'hidrogen i els elements del grup 1 tenen una configuració electrònica ns^1, en què n és el nombre quàntic principal del darrer nivell, o el més extern. Aquest nivell normalment s'anomena nivell o capa de valència perquè és el que caracteritza químicament l'element. Segons el tipus de configuració electrònica hom diferencia quatre grans blocs, s, p, d i f, els quals solen diferenciar-se amb colors diferents en algunes taules periòdiques.

Bloc s
Els elements dels grups 1 i 2 (a la figura 1A i 2A), l'hidrogen, els alcalins, alcalinoterris i l'heli, tenen configuracions ns^1 els dos primers i ns^2 els dos darrers, i s'anomenen elements del bloc s. Està constituït per un total de catorze elements. Són elements químics els quals àtoms tenen electrons que inicien l'ocupació d'un nou nivell d'energia, la qual cosa fa que siguin fàcilment ionitzables i formin cations. És excepcional la posició de l'heli situat a la dreta de la taula periòdica per agrupar-lo amb la resta de gasos nobles amb els quals comparteix propietats. Això és degut al fet que el nivell n = 1 no té orbitals p i l'heli completa el nivell.

Bloc p

Els grups del 13 al 18 (a la figura 3A a 8A) tenen configuracions de ns^2np^1 a ns^2np^6, respectivament, i s'anomenen elements del bloc p. En total hi ha trenta-sis elements si es compten els artificials del període 7. Són elements químics amb àtoms que completen els subnivells energètics s i p. És un bloc on es produeix una transició del caràcter metàl·lic a no metàl·lic, de l'esquerra cap a la dreta, i més aviat els situats a la part superior que els de la part inferior. Al mig queden elements amb propietats entre uns i els altres que s'anomenen metal·loides o semimetalls. Són el bor (B), el silici (Si), el germani (Ge); l'arsènic (As), l'antimoni (Sb), el tel·luri (Te) i el poloni (Po), situats en una diagonal que baixa d'esquerra a dreta. Els que tenen caràcter no metàl·lic són elements que poden acceptar electrons i formar anions. La configuració del nivell de valència ns^2np^6correspon als gasos nobles i és especialment estable, com es dedueix de les seves baixes reactivitats.

Bloc d
Els elements dels grups 3 al 12 (a la figura 3B a 8B i 1B i 2B) s'anomenen elements elements del bloc d. Cada una de les sèries horitzontals d'aquests elements correspon a l'ocupació tardana del subnivell d del nivell (n-1) d'aquests àtoms. Com qualsevol subnivell d pot acollir 10 electrons, hi ha 10 elements per a cada nivell (4, 5 i 6) d'aquest bloc. Tots tenen propietats típiques dels metalls. Els del període 7 són tots artificials i es desintegren molt ràpidament. S'han sintetitzat pocs àtoms i no és possible mesurar cap propietat. Els elements dels grups 3 a l'11, això és tot el bloc d excepte el grup 12, s'anomenen elements o metalls de transició.

Bloc f

Finalment, queda el bloc f, els dels elements de transició interna, constituït pels lantanoides i actinoides que van ocupant els 14 orbitals f del nivell (n-2). Cadascun dels dos grups té elements molt semblants, amb propietats que es diferencien molt poc. Els situats després de l'urani (U) s'anomenen elements transurànics, i són tots artificials i inestables, excepte els primers (neptuni, plutoni i americi) tots els seus isòtops tenen vides mitjanes de molt curta durada.

Propietats periòdiques

Propietats periòdiques atòmiques

Radi atòmic

El radi atòmic és la distància entre el nucli de l'àtom i els electrons més externs.

 En un grup de la taula periòdica, creix en augmentar el nombre atòmic , perquè el darrers electrons, anomenats de valència, estan cada vegada més allunyats del nucli. El primer factor que hom ha de considerar és que en baixar dins d'un grup, els electrons ocupen cada vegada nivells d'energia més alts i, per tant, més allunyats del nucli, la qual cosa dona lloc a un augment del radi atòmic. En part, aquest augment es compensa amb l'increment de la càrrega nuclear. Els àtoms que estan més avall tenen una càrrega nuclear més elevada que els que estan per damunt i, segons la llei de Coulomb, l'atracció a la qual estan sotmesos els electrons és major, cosa que fa que s'aproximin al nucli disminuint el radi. Però aquest segon factor es veu en part compensat per un tercer factor, l'efecte d'apantallament dels electrons interiors, els quals repel·leixen els electrons exteriors i redueixen l'efecte d'atracció del nucli. En conjunt, aquests tres factors donen que el radi atòmic augmenti considerablement en davallar dins d'un grup i els elements que estan situats a la part inferior de la taula periòdica tinguin radis majors.
 En un període, el radi atòmic disminueix en augmentar . En aquest cas intervenen només dos factors: el primer és que els electrons més externs estan situats tots en el mateix nivell, la qual cosa fa que el radi no variï. El segon factor és l'augment de la càrrega nuclear que es produeix en avançar dins d'un període. Això produeix una contracció dels àtoms i una disminució del seu radi. Els electrons interns produeixen apantallament, però per a tots els àtoms és el mateix, ja que els nivells ocupats sempre són els mateixos i no és un factor determinant.

Volum atòmic

El volum atòmic és l'espai que ocupa un àtom.
 En un grup, augmenta en augmentar el nombre atòmic . La causa, la trobam perquè dins d'un grup en baixar cada vegada hi ha ocupats nivells més alts d'energia que estan més allunyats del nucli. Això fa que els àtoms tenguin un volum major. Hi ha un factor que s'oposa a aquest augment i és l'augment de càrrega nuclear que fa que l'atracció electroestàtica sigui més elevada en baixar dins d'un grup. Però part d'aquesta atracció es veu compensada per l'apantallament, la repulsió dels electrons més interns.
 En un període passa el mateix que amb el radi, és a dir, disminueix en augmentar . La causa, la trobam perquè els electrons ocupen el mateix nivell energètic i en avançar en el període la càrrega nuclear augmenta. Per això, l'atracció electroestàtica sobre els electrons augmenta i el volum es redueix.

Energia de ionització

L'energia de ionització és l'energia que cal subministrar a un àtom en el seu estat fonamental i gasós per a arrancar-li un electró, segons l'equació

Pel primer electró, s'anomena primera energia de ionització, pel segon, 2a energia de ionització i així successivament.

 En un grup disminueix en augmentar el nombre atòmic . A la figura adjunta, s'observa clarament amb els gasos nobles (els màxims) o amb els alcalins (els mínims). La causa d'aquesta variació és que, si bé en baixar dins d'un grup, la càrrega nuclear és major i, en principi, l'atracció electroestàtica també ho és, la posició dels electrons de la darrera capa és cada vegada més allunyada del nucli i això fa que l'atracció electroestàtica, segons la llei de Coulomb, sigui menor, ja que és inversament proporcional a la distància entre càrregues (protons del nucli-electró més extern). També s'ha de considerar la repulsió dels electrons interns, l'apantallament, que redueix l'atracció del nucli. Amb tot això, les energies de ionització disminueixen en baixar dins d'un grup, per tant els àtoms que se situen a la part més baixa de la taula periòdica són més fàcilment ionitzables.
 En un període creix en augmentar . Quan s'avança dins d'un període augmenta el nombre de protons i, per tant, la càrrega nuclear, produint una atracció electroestàtica major sobre els electrons. Contràriament al que passa dins d'un grup, tots els electrons més externs en un període ocupen la mateixa capa i, per això, se situen d'entrada a distàncies semblants del nucli i amb la major càrrega nuclear s'aproximen més a aquest. Així, els electrons més externs estan més propers al nucli, la qual cosa implica major atracció electroestàtica i, també, la càrrega nuclear és major, per tant també major atracció. En conseqüència, les energies de ionització augmenten considerablement dins d'un període com s'observa a la figura. El darrer element del període, el gas noble, és el que té l'energia de ionització major. Després hi ha una baixada en omplir-se un altre nivell energètic i allunyar-se el darrer electró del nucli.

Electroafinitat
Electroafinitat o afinitat electrònica és l'energia que desprèn un àtom en el seu estat fonamental i gasós quan guanya un electró i passa a ser un anió. Podem representar-ho per

 En un grup disminueix en augmentar el nombre atòmic , ja que els nous electrons se situen en orbitals cada vegada més allunyats del nucli on l'atracció electroestàtica del nucli és més feble per la llei de Coulomb.
 En un període creix en augmentar  perquè la càrrega nuclear augmenta en avançar en un període i els electrons se situen en el mateix nivell, per tant cada vegada més propers al nucli i més atrets.

Electronegativitat

Electronegativitat és la capacitat que té un àtom per a atreure els electrons de l'enllaç covalent que forma amb un altre àtom, és a dir, tendència que presenta un àtom a compartir desigualment els electrons de l'orbital o els orbitals del seu enllaç. Hom ha convingut d'acceptar com a valor de l'electronegativitat d'un element el valor que aquest agafa en combinar-se amb l'hidrogen. L'escala d'electronegativitats fou calculada per primera vegada per Linus Pauling a partir dels moments dipolars, electroafinitats i potencials de ionització, bo i donant com a valor patró 4,0 per al fluor. L'electronegativitat és emprada en fórmules empíriques per a calcular el caràcter iònic d'un enllaç i també per a calcular de manera aproximada la longitud d'enllaç a partir de la longitud dels radis covalents.
 En un grup disminueix en augmentar , ja que si bé augmenta la càrrega nuclear també augmenten els nivells ocupats i els darrers electrons, els que formen els enllaços estan més allunyats del nucli en davallar a la taula periòdica.
 En un període creix en augmentar , ja que augmenta la càrrega nuclear efectiva per l'augment del nombre de protons i els electrons se situen tots en el mateix nivell. Els elements químics situats a la dreta de la taula periòdica són els més electronegatius exceptuant-ne els gasos nobles.

Propietats periòdiques físiques

Les propietats físiques dels elements químics varien seguint la llei periòdica. Propietats com el punt de fusió, el punt d'ebullició, la conductivitat tèrmica, la calor específica, la conductivitat elèctrica, la duresa i la densitat mostren variacions periòdiques amb el nombre atòmic. Sovint la variació no és tan regular com la que es produeix amb les propietats periòdiques atòmiques, perquè la relació d'aquestes propietats físiques i la configuració electrònica no és directa.

Com a exemples, es poden citar la densitat i els punts de fusió. Ambdues propietats es poden representar respecte al nombre atòmic, i s'hi observa una successió de màxims i mínims. En el cas de la densitat, els mínims corresponen als metalls alcalins i augmenta en davallar dins del grup. En el cas dels punts de fusió, els mínims corresponen als gasos nobles, i també augmenten els punts de fusió en davallar dins del grup.

Propietats periòdiques químiques
Les propietats periòdiques químiques són les que emprà Mendeléiev per a descobrir la llei periòdica. A continuació se'n detallen algunes:

València

La valència dels elements és una propietat periòdica, ja que tots els elements d'un grup tenen la mateixa valència.

Per exemple, tots els alcalins tenen valència 1; tots els alcalinoterris tenen una valència 2, tots els gasos nobles tenen valència 0, tots els halògens tenen valència 1, etc. Així, els òxids, per exemple, dels elements del grup 14, tenen fórmules iguals: CO₂, SiO₂, GeO₂, etc.

També s'observa una regularitat en un període que es representa a la taula adjunta. Si deixam a part els elements dels blocs d i f, i només ens fixam en els dels blocs s i p (grups 1 i 2 i del 13 al 18), s'observa que la valència s'incrementa en una unitat en passar d'un element a l'altre, fins a arribar a un màxim, en l'element del grup 14, i després es redueix d'unitat en unitat fins als gasos nobles (0). L'explicació d'aquest fet és molt simple: els elements del mateix grup de la taula periòdica tenen el mateix nombre d'electrons en la seva capa de valència.

Caràcter metàl·lic

Els metalls són materials generalment durs i tenaços, bons conductors de la calor i de l'electricitat, per bé que aquesta conductivitat disminueix en augmentar la temperatura; mentre que els no-metalls poden ser aïllants o semiconductors, a temperatures baixes són mals conductors de l'electricitat i la calor, per bé que la conductivitat elèctrica en aquests materials augmenta amb la temperatura. El caràcter metàl·lic disminueix a mesura que hom es desplaça d'esquerra a dreta en un període. El caràcter dels primers grups, situats a l'esquerra, (alcalins i alcalinoterris) és molt elevat i disminueix progressivament fins a arribar als halògens i als gasos nobles, típicament no-metalls, ubicats a l'extrem dret de la taula periòdica.

Dins del bloc p hi ha uns elements anomenats semimetalls, si bé tenen un comportament bàsicament de no-metall, presenten fenòmens com el de la semiconductivitat i defineixen una zona intermèdia entre els metalls i els no-metalls. Aquest elements són el bor del 2n període, el silici el 3r període, el germani i l'arsènic del 4t període, l'antimoni i el tel·luri del 5è, i l'àstat del 6è.

Els elements superpesants, a partir del meitneri, són elements artificials dels quals se sintetitzen uns pocs àtoms amb una vida mitjana de mil·lisegons. Per tant, no se'n pot confirmar el caràcter metàl·lic.

Història

Tríades de Döbereiner

El 1817, el farmacèutic alemany Johann W. Döbereiner observà que la massa atòmica de l'estronci era quasi igual al valor mitjà de les masses atòmiques del calci i del bari, elements químicament semblants en propietats físiques i químiques a l'estronci:

La densitat també era una propietat que complia aproximadament la mateixa regla. El 1829, mostrà l'existència de més grups de tres elements, tríades, que formaven compostos de composició similar i amb propietats semblants: sofre, seleni i tel·luri; clor, brom i iode; liti, sodi i potassi. L'any 1850, els químics havien aconseguit identificar al voltant de 20 tríades, que indicaven entre els elements una certa regularitat.

El caragol tel·lúric
El 1862, el francès Alexander Émile Béguyer de Chancourtois construí el seu vis tellurique ('cargol tel·lúric'), en la qual els elements estaven situats per ordre creixent de masses atòmiques en una hèlix al voltant d'un cilindre vertical, de manera que els elements que quedaven els uns sota els altres tenien propietats semblants. Això ho aconseguí fent que la diferència de masses atòmiques en cada volta fos de 16 unitats. Descobrí la llei periòdica però no aconseguí publicar el gràfic i quan ho aconseguí no fou conegut pels químics.

Octaves de Newlands

El 1864, un químic anglès, John A. R. Newlands, descobrí que en ordenar els elements coneguts segons la seva massa atòmica, el vuitè element tenia propietats similars al primer, el novè al segon i així successivament, cada vuit elements, les propietats es repetien. Ho anomenà llei de les octaves, recordant les notes musicals. Tanmateix, no trobà suport entre la comunitat científica.

Taula de Mendeléiev

El 1869, Mendeléiev publicà el que es considera la primera taula periòdica. Ordenà els elements seguint la seva massa atòmica, però no fixà el període de repetició de propietats, sinó que l'amplià a mesura que augmentava la massa atòmica. Invertí l'ordre d'alguns elements perquè encaixessin les seves propietats amb les dels elements adjacents, considerà que hi havia masses atòmiques mal calculades i deixà forats, indicant que corresponien a elements encara no descoberts.

Paral·lelament, el 1870, el químic alemany Lothar Meyer estudiava els elements de manera gràfica, representant el volum de cada àtom en funció del seu pes, obtenint una gràfica en ones cada vegada majors. Fou el descobriment de la llei periòdica, però va arribar un any massa tard.

Modificacions posteriors
El descobriment dels gasos nobles, elements desconeguts per Mendeléiev, obligà a cercar-los lloc en la taula periòdica. Així, William Ramsay proposà el 1897 la creació d'un nou grup d'elements.

El 1902, el químic txec Bohuslav Brauner publicà una taula periòdica on separà de la resta d'elements als lantanoides, que els posà ocupant una única casella amb onze elements.[28]

El 1905 el químic suís Alfred Werner publicà una versió llarga de la taula periòdica que separa els metalls de transició dels lantanoides. El 1928 el científic francès Charles Janet publicà una taula periòdica llarga basant la seva organització en la configuració electrònica dels àtoms sorgida de la mecànica quàntica. La seva transformació fou la que donà origen a la taula actual.

L'any 1945, Glenn Seaborg demostrà l'existència de la sèrie dels actinoides, molts dels quals, els transurànids, sintetitzà amb els seus col·laboradors durant la primera meitat del . Segons Seaborg, els actinoides havien de formar un grup com ho feien els lantanoides i per sota d'aquests, separats dels metalls de transició del bloc d amb els quals havien estat agrupats inicialment.

L'any 2019 fou proclamat Any Internacional de la Taula Periòdica dels Elements Químics per la UNESCO.

Altres formats
Diferents científics han proposat altres formats de la taula periòdica sense abandonar l'ordenació per ordre creixent de nombre atòmic, algunes de les quals figuren a continuació. Algunes permeten visualitzar millor la llei periòdica d'algunes propietats, però només són emprades per una minoria de científics. La taula periòdica d'ús generalitzat és la que s'ha descrit en aquest article i és l'oficial de la IUPAC.

En altres camps

Motiu artístic
Diferents artistes plàstics han emprat la taula periòdica com a motiu per a les seves obres. Alguns d'ells són l'estatunidenc Blair Bradshaw que ha realitzat diferents obres a partir de la taula periòdica o dels elements així com s'hi representen: Periodic table (black) (2009), 3 hydrogens (2011), The city loved him so (2010), Periodic table (tower) (2014) i Periodic table (2016), entre altres; Erich Füllgrabe, Keith Wilson a l'escultura Periodic table (2004); Rebecca Kamen en el seu projecte Divining Nature: An Elemental Garden (2009); Sonya Rapoport en el collage Objects On My Dresser, Phase 10: Periodic Table of the Elements (1983); Simon Patterson en les obres 24 hours 16 hours (1995), Untitled 24 hours i d'altres; o David Clark.

Món comercial
La taula periòdica s'empra en el món comercial com a motiu de decoració en molts d'objectes: pòsters, camisetes, corbates, tasses, vitralls, autobusos, etc. I els símbols dels elements són emprats per jugar amb ells i construir-hi paraules, les quals s'empren per estampar-les en camisetes, tasses, etc.

Per altra banda l'estructura de la taula periòdica ha servit de font d'inspiració per a molts d'autors que han ordenat de forma semblant altres temes creant símbols seguint el mateix estil que l'emprat per simbolitzar els elements químics. En el camp de la literatura s'han dissenyat taules periòdiques sobre característiques de la narrativa, narradors actuals estatunidencs, escriptors més destacats de tots els temps, de les saga de Harry Potter, de Joc de Trons, de la Terra Mitjana, Star Wars, etc. En el camp del disseny gràfic també s'ha utilitzat l'estructura de la taula periòdica per classificar-hi 100 dels tipus de lletra més usats. En el camp dels esport s'han dissenyat taules semblants a la periòdica per recollir els millors jugadors de futbol americà, guanyadors de Grans Premis de Fórmula 1… A cinematografia s'han dissenyat taules periòdiques amb les millors pel·lícules de ciència-ficció, etc.

La taula periòdica més petita
El 2010, la Universitat de Nottingham rebé un rècord mundial Guinness per crear la taula periòdica més petita del món. Gravada sobre un cabell del químic Martyn Poliakoff, mesurava només 90 µm per 46 µm. El 2019 investigadors de la mateixa universitat bateren el seu propi rècord, utilitzant litografia de feixos d'electrons. La taula es presentà en un xip de silici juntament amb retrats minúsculs de Dmitri Mendeléiev i Iuri Oganessian, l'única persona viva el 2019 que té un element químic amb el seu nom (oganessó). Cada retrat és d'uns 30 μm per 30 μm, i la taula periòdica de només 14 µm per 7 µm, menys d'una quarantena de l'àrea del registre anterior. Richard Cousins la creà fent servir un feix d'electrons d'alta energia de pocs nanòmetres de diàmetre per fer una resistència a una pel·lícula de polímer. El patró 3D fet a la resistència fou transferit al silici mitjançant gravat d'ions i es diposita una capa fina d'or sobre el xip mitjançant l'evaporació tèrmica. L'or només s'adhereix a l'àrea definida pel feix d'electrons i la resta s'alimenta simplement en un dissolvent que deixa el patró desitjat.

Referències

Bibliografia

Enllaços externs

 Taula periòdica: taula periòdica interactiva
 Webelements: informació de tots els elements de la taula periòdica (en anglès)
 Llista dels elements i traducció a diverses llengües
 Periodic Table Formulations: pàgina web en què hi ha una relació exhaustiva de diferents formats de la taula periòdica
 Taula periòdica
 Taula periòdica dels elements segons la seva abundància natural relativa


text:
PM-afternoon-eNews
Dykstra Pleads Guilty to Bankruptcy Fraud
By Deborah Crowe
Former baseball slugger Lenny Dykstra pleaded guilty on Friday to bankruptcy fraud and other federal charges for selling items taken from his mansions in Ventura County.
Dykstra, 48, who played for the New York Mets and Philadelphia Phillies in the 1980s and 1990s, pleaded guilty to three felony counts: bankruptcy fraud, concealment of assets, and money laundering, according to the U.S. Attorney's Office in Los Angeles. He faces a maximum sentence of 20 years in federal prison.
In a plea agreement filed under seal on June 26, Dykstra admitted that after filing for bankruptcy in 2009 he lied about taking and selling items that were part of the bankruptcy estate. He was accused of taking $400,000 worth of fixtures, including chandeliers, mirrors, a stove and a grandfather clock from his mansion, and $15,000 worth of baseball equipment and memorabilia, including gloves, balls and bats, and secretly selling them.
Dykstra already is serving a three-year term in state prison for grand theft auto and a concurrent 270-day sentence for lewd exposure and assault.
"The bankruptcy-related conduct to which Mr. Dykstra pleaded guilty constitutes an egregious abuse of the bankruptcy system and will not be tolerated," Peter C. Anderson, the U.S. bankruptcy trustee for Region 16, said in a statement.
Attorney Sentenced to Prison in Carson Extortion Case
Attorney Gets 80 Months in Carson Extortion Case
Disney Earnings Leaker Admits to Scheme With Boyfriend
Woman Sentenced in Medical Fraud Case
Former Internet Company CFO Sentenced
Attorney Sentenced in Saban Tax Case
Former Long Beach Medical Supply Shop Owner Pleads Guilty to Fraud

redpajama_set_name: RedPajamaCommonCrawl


text:
<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="activity_gallery_permission_request_explanation">Permiso de almacenamiento necesario. Por favor habilitar en los ajustes del teléfono.</string>
    <string name="activity_gallery_permission_request_settings">Ajustes</string>
    <string name="activity_gallery_action_select_all">Seleccionar todo</string>
    <string name="activity_gallery_action_clear">Limpiar</string>
    <string name="activity_gallery_no_images">No hay fotos.</string>
    <string name="activity_gallery_max_selection_reached">Has alcanzado el número máximo de fotos.</string>
    <string name="activity_gallery_will_exceed_max_selection">Usted excederá el número máximo de fotos.</string>
    <string name="activity_gallery_bucket_all_media">Todas las fotos</string>
    <plurals name="activity_gallery_count_selection">
        <item quantity="one">%d seleccionado</item>
        <item quantity="other">%d seleccionados</item>
    </plurals>
</resources>

redpajama_set_name: RedPajamaGithub


Apria Healthcare Headquarters HQ, mailing and postal office address is given with the Apria Healthcare contact telephone number, fax number and email address. Apria Healthcare headquarters HQ and customer service department provides help and support to the customers during the working hours and after business hours through emails, phones and online. Various customers are looking for Apria Healthcare address or customer service phone number of Apria Healthcare, Apria Healthcare toll free phone number, customer support contact number and helpline number of Apria Healthcare.
If you want to more information about trendy range of Apria Healthcare products and services including Apria Healthcare headquarters HQ office and customer service number, 24 hours phone number of Apria Healthcare, addresses of Apria Healthcare. So you can call their customer service team and call centre to receive a prompt resolution related issue you might have.
Here listed Apria Healthcare Phone Number, to be able to contact Apria Healthcare headquarters HQ and customer care department. You can contact the Apria Healthcare Customer Support at the following Apria Healthcare Contact Number to get information about your Apria Healthcare Product or to receive help regarding any Apria Healthcare Support you may need.
Apria Healthcare mailing / postal and corporate office address, Apria Healthcare toll free number, customer care service helpline number, corporate headquarters HQ office address of Apria Healthcare, customer support number and email id is given with official web page links, social profiles, ratings and reviews.
Above maintained number is not toll free helpline number of Apria Healthcare. So, the users will be charged with normal calling rates. The telephonic customer support number of Apria Healthcare is available during the working hours.
This is the customer support email id of Apria Healthcare. Apria Healthcare email support is available 24 x 7 and you can expect their reply within 24 hours.
This is the physical, postal, payment and mailing office address of Apria Healthcare is listed below. Customers can contact to the company for any query to this address of Apria Healthcare.
Apria is the worst when trying to get CPAP supplies. I have been waiting since October, 2016 to get new supplies for my CPAP. I have gotten more than one excuse and now my prescription is expired and I have to get a new one. Is there anyone else that can help. Oh and god forbid, don't have Medicaid.
reviews about this company on their website. If they are not careful, the company will have a class action suit to defend.
Apria is working with me on a workers Comp claim. I had a prescription sent to them for a portable concentrator ( carry not on rollers) in October 2116. I had to do the leg work to Workers Comp to get it approved for them to order it. They could not get the paper work correct so Workers Comp would not ok it. After I got through with it on my end I told them how they needed to do it for Workers Comp to pay. (That was not my job in the first place) Here it is May 2017 and I still do not have it. This is awful. I have made several calls local with no results and I have called several times to a Scott in South Florida. He does not return my calls. They take my number and say he will call me back. NO HE DOESENT. Finally today 5/25/2017 I called and got Scott just to find out that they just ordered my machine and would probably be here when I return home. The reason I wanted this was for travel. I have lung problems and cannot walk long distances. I am now leaving on a cruise WITH OUT THE SMALL CONCENTRATER which is now going to restrict my activies on the cruise. It has been 7 mos. I have been working on this for my cruise and any travels I may want to take. This is awful service. My wife waited about two months to get her BiPap and only when she threaten to change companies did see get a phone call that her machine was ready. They had lost her paperwork and she had to call and have the paperwork resent to Apria. This is not right. So fed up and disgusted with them. Seriously thought about talking to a lawyer.
what is wrong with this company they have the worst customer service !!!!
The worst customer service possible. These people just took nearly $500.00 out of my bank account via my debit card without any notice to me whatsoever–no paper statement, no email, no subsequent communication explaining the charges, nothing. When I called to investigate I found they had the wrong address–these charges may not even have been for my account–and when I finally asked to speak to a supervisor they transferred me to another CSR who then hung up on me. I am cancelling with them and will NEVER use them again. Beware!
YOU REALLY SUCH AS A COMPANY IN WHOLE !! YOUR SERVICE DISTRICT ALL WHO NEED OXYGEN .
YORK SERVICE NOTHING !!! DISGUSTING UNPLEASANT EMPLOYEE'S. I AM GOING TO MAKE YOU LOOK AS BAD AS YOU ARE TO THE WORLD AS A COMPANY. AFTER A YEAR AND A HALF, NO ONE HAS CHECK ED MY UNIT. WHEN THIS CONTRACT IS UP. BYE -BYE TO A GARBAGE WHAT EVER YOU WANT TO CALL THIS SUPPORT TO BE ONLY MONEY NOT PROFESSIONAL CARE NOR SERVICE .


text:
Public Engagement + Involvement
100 Ways of Using Data to Make Lives Better
#datasaveslives
Research + Education
Informatics, Statistics and Data Science
Ethics and Governance
e-Infrastructure
Understanding Chronic Disease
Child and Maternal Health
Environmental and Public Health
Precision Medicine and Clinical Trials
Online and in the Media
Informing Policy
Events + Courses
Researchers at The Farr Institute used the network's extensive data resources and interdisciplinary skills to understand the risks, causes and most effective treatments of chronic or long term diseases.
While some of these diseases can be prevented through, for example, changes to lifestyle, many others result in lifelong medication and treatment. Patients can often suffer from several chronic diseases simultaneously which can have a huge impact on day-to-day life and long term health.
Research groups across The Farr Institute's network combined the expertise of leading clinicians and epidemiologists with extensive data resources to improve the understanding of diseases including:
The Institute's investigators worked with colleagues from across the world to contribute to the understanding of chronic disease by delivering high-quality, cutting edge research by linking electronic health data with other forms of research and sources of data. Research in this area is improving the health and care individual patients and whole populations and, in turn, reducing strain on health and care systems.
The Implications of GDPR...
A brief has been produced as part of the work of The Farr Institute Information Governance...
Amitava Banerjee Shares His...
As The Farr Institute's funding comes to a close, Amitava Banerjee, Senior Lecturer in Clinical Data...
Ashley Akbari Tells Us...
We talk to Ashley Akbari, Senior Research Manager and Data Scientist at Swansea University. What does...
Kerina Jones Reflects on...
We recently spoke with Kerina Jones, Associate Professor of Health Informatics at Swansea University, about her...
Celebrating 5 Years of...
The Farr Institute's five years of funding comes to a close in October 2018 with the...
Back to top+
Farr Institute Design by Firefly
Design by Firefly
Farr Institute
Title* Dr Professor Associate Prof Mr Mrs Miss Ms
Submit +


text:
2.56Select Videocasts and Podcasts
2.59Select Writers, Researchers, etc.
2.62Wikimedia Commons
2.63Wikipedia
2.64Wikiquotes
2.65Wikisource
2.66Wikivoyage
Add or take a free, open Materials Science course.
Add free, open Materials Science subjects below.
Add free, open Materials Science courses
Electronic, Optical and Magnetic Properties of Materials http://ocw.mit.edu/courses/materials-science-and-engineering/3-024-electronic-optical-and-magnetic-properties-of-materials-spring-2013/ MIT non-degree Prof. Polina Anikeeva, Prof. Geoffrey Beach, Niels Holten-Andersen Browser Start anytime English Undergraduate
Information Exploration: Becoming a Savvy Scholar http://ocw.mit.edu/courses/materials-science-and-engineering/3-093-information-exploration-becoming-a-savvy-scholar-fall-2006/ MIT non-degree Prof. Donald Sadoway (Faculty Liaison), Patty Durisin Barbera (Assistant Instructor), Angie Locknar Browser Start anytime English Undergraduate
Introduction to Modeling and Simulation http://ocw.mit.edu/courses/materials-science-and-engineering/3-021j-introduction-to-modeling-and-simulation-spring-2008/ MIT non-degree Prof. Markus Buehler, Dr. Timo Thonhauser, Prof. Raúl Radovitzky Browser Start anytime English Undergraduate
Introduction to Modeling and Simulation http://ocw.mit.edu/courses/materials-science-and-engineering/3-021j-introduction-to-modeling-and-simulation-spring-2012/ MIT non-degree Prof. Markus Buehler, Prof. Jeffrey Grossman Browser Start anytime English Undergraduate
Introduction to Solid State Chemistry http://ocw.mit.edu/courses/materials-science-and-engineering/3-091-introduction-to-solid-state-chemistry-fall-2004/index.htm?utm_source=Featured-Course_06-10-10 MIT non-degree Prof. Donald Sadoway Browser Start anytime English undergraduate
Materials Processing http://ocw.mit.edu/courses/materials-science-and-engineering/3-044-materials-processing-spring-2013/ MIT non-degree Prof. Chris Schuh Browser Start anytime English Undergraduate
Materials Science and Engineering http://ocw.mit.edu/courses/materials-science-and-engineering/ MIT non-degree Browser Start anytime English Undergraduate, Graduate
Modern Blacksmithing and Physical Metallurgy http://ocw.mit.edu/courses/materials-science-and-engineering/3-a04-modern-blacksmithing-and-physical-metallurgy-fall-2008/ MIT non-degree Michael Tarkanian Browser Start anytime English Undergraduate
Principles of Engineering Practice http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-851-advanced-data-structures-spring-2010/ MIT non-degree Prof. Lionel C. Kimerling Browser Start anytime English Undergraduate
Chandler, David L. 2013. How to make ceramics that bend without breaking: New materials developed at MIT could lead to actuators on a chip and self-deploying medical devices. September 26. Cambridge, MA: MIT News Office.
Chandler, David L. 2013. Improved nuclear fuel-rod cladding might prevent future Fukushimas: A substitute for traditional zircaloy could greatly reduce the danger of hydrogen explosions. Cambridge, MA: MIT News Office.
Reuell, Peter. 2014. Magnetic attraction: System that prompts objects to 'float' in suspension could prove boon to manufacturing with fragile materials. September 2. Cambridge, MA: news.harvard.edu.
Trafton, Anne. 2014. Engineered proteins stick like glue — even in water: New adhesives based on mussel proteins could be useful for naval or medical applications. September 21. Cambridge, MA: MIT News Office.
Xiao, Bei, Bruce Walter, Ioannis Gkioulekas, Todd Zickler, Edward Adelson, Kavita Bala. 2014. Looking against the light: How perception of translucency depends on lighting direction. 14(3):17, 1–22. Journal of Vision.
3D Printing of Lightweight Cellular Composites. 2014. 3D Printing of Lightweight Cellular Composites. Cambridge, MA: Harvard University Youtube channel.
Select Videocasts and Podcasts[edit]
Select Writers, Researchers, etc.[edit]
Wikimedia Commons[edit]
Wikimedia Commons: https://commons.wikimedia.org/wiki/Main_Page
Wikipedia[edit]
Wikipedia: https://www.wikipedia.org/
Wikiquotes[edit]
Wikiquotes: https://en.wikiquote.org/wiki/Main_Page
Wikisource[edit]
Wikisource: https://wikisource.org/wiki/Main_Page
Wikivoyage[edit]
Wikivoyage: https://www.wikivoyage.org/
Battery Technologies: http://worlduniversity.wikia.com/wiki/Battery_Technologies
Chemistry: http://worlduniversity.wikia.com/wiki/Chemistry
Industrial Engineering: http://worlduniversity.wikia.com/wiki/Industrial_Engineering
Green Chemistry: http://worlduniversity.wikia.com/wiki/Green_Chemistry
Laboratory courses online at World University and School: http://worlduniversity.wikia.com/wiki/Laboratory_courses_online_at_World_University_and_School
Materials Science: http://worlduniversity.wikia.com/wiki/Materials_Science
Mechanical Engineering: http://worlduniversity.wikia.com/wiki/Mechanical_Engineering
Nuclear Science and Engineering: http://worlduniversity.wikia.com/wiki/Nuclear_Science_and_Engineering
Organic Chemistry: http://worlduniversity.wikia.com/wiki/Organic_Chemistry
Physics: http://worlduniversity.wikia.com/wiki/Physics
STEM Education - Science, Technologies, Engineering and Mathematics: http://worlduniversity.wikia.com/wiki/STEM_Education_-_Science,_Technologies,_Engineering_and_Mathematics
Science: http://worlduniversity.wikia.com/wiki/Science
Digital and Print catalog
Broadcast to radio frequencies
Broadcast to TV / television
(Search on the word 'lists' here, too: http://worlduniversity.wikia.com/wiki/Virtual_Worlds)
Active Worlds Educational Universe (AWEDU). 2012. http://www.activeworlds.com
Kaneva. 2014. http://www.kaneva.com/
SmallWorlds. 2014. https://www.smallworlds.com/
There.com. 2014. http://www.there.com/
Twinity. 2014. http://www.twinity.com/en/choose-your-free-avatar
World of Warcraft in School. 2014. http://wowinschool.pbworks.com/w/page/5268731/FrontPage
About Me - World University and School - http://about.me
Wer Kennt Wen - World University and School - http://www.wer-kennt-wen.de/
Google + Hangout - https://tools.google.com/dlpage/hangoutplugin - http://www.google.com/+/learnmore/hangouts/
Meeting Burner - http://www.meetingburner.com/index?page=signup-v2 – up to 15 connection
ooVoo - http://www.oovoo.com/home.aspx
Paltalk - http://www.paltalk.com
sifonr - free communication - http://www.sifonr.com/
Tokbox | OpenTok - API - http://tokbox.com/opentok
Vyew - http://vyew.com/
Web Huddle - https://www.webhuddle.com/homepage.jsp - http://sourceforge.net/projects/webhuddle/
The "Universitian" Newspaper at WUaS
Wet Paint - http://wikisineducation.wikifoundry.com/
All content on this site is freely available under a Creative Commons Attribution-ShareAlike 3.0 International (CC BY-SA 3.0) - https://creativecommons.org/licenses/by-sa/3.0/ .
LANGUAGE TEMPLATE: http://worlduniversity.wikia.com/wiki/LANGUAGE_TEMPLATE
MUSEUM TEMPLATE: http://worlduniversity.wikia.com/wiki/MUSEUM_TEMPLATE
NATION STATE TEMPLATE: http://worlduniversity.wikia.com/wiki/NATION_STATE_TEMPLATE
WUaS's Guidestar.org listing - https://www.guidestar.org/organizations/27-3105368/world-university-school.aspx .
http://worlduniversityandschool.org
Retrieved from "https://wiki.worlduniversityandschool.org/w/index.php?title=Materials_Science&oldid=4445"


text:
In this section you will find information about South Australia's public hospitals and related health services, including emergency departments, elective surgery, and outpatient clinics. You can also find information about car parking fees at our metropolitan hospitals and things to know about going to hospital as a patient or visitor.
Car parking fees
Information on car parking fees for the various Adelaide metropolitan public hospitals - SA Health
Waiting for elective surgery: Public hospital elective surgery priority (urgency) ratings, information for patients and GPs
Going to hospital? What to know and expect
What to expect from your test, types of treatment and going to hospital
Hospital Avoidance and Discharge Support
Short term support for people who are at immediate risk of a hospital presentation and early supported discharge services
SA Health's Specialist Outpatient Services. Outpatient referral guidelines, outpatient clinic lists and appointment information for clinicians.
Rehabilitation services across South Australia's Local Health Networks provide a range of care and recovery options for veterans.
Flinders Medical Centre
Flinders Medical Centre (FMC) is the southern area's largest hospital and provides medical services for people living in the southern metropolitan area of Adelaide.
Hampstead Rehabilitation
Hampstead Rehabilitation Centre - aims to bring about the highest level of recovery following a loss of function or ability or independence
Lyell McEwin Hospital
Lyell McEwin Hospital (LMH) is a public acute care teaching hospital with a 24 hour Emergency Service located in Northern Adelaide, South Australia
Modbury Hospital
A 174 bed, acute care teaching hospital that provides inpatient, outpatient and emergency services in Adelaide's north-eastern suburbs
My Home Hospital
My Home Hospital is a public service funded through Wellbeing SA, that delivers hospital-level care to patients in the comfort and privacy of their own home.
Noarlunga Hospital
Noarlunga Hospital provides a range of inpatient, ambulatory and outpatient services for people living in the southern metropolitan area of Adelaide.
Repat Health Precinct
The Repat is returning the site to a thriving health precinct. The Chapel, Remembrance Gardens, Museum and SPF Hall will be protected for future generations.
Regional Hospitals and Health Services
Local hospitals and health services in country South Australia deliver high quality health care to all rural South Australians.
Royal Adelaide Hospital
Information for General Practitioners including the ramp down of services, clinical move and changes to referral processes.
St Margaret's Hospital
Services that are available at St Margaret's Hospital
The Queen Elizabeth Hospital (TQEH)
The Queen Elizabeth Hospital (TQEH) provides inpatient, outpatient, emergency and mental health services to over 250,000 people living in Adelaide's Western suburbs
Women's and Children's Hospital
The Women's and Children's Hospital (WCH) provides state of the art health care for women and children in Adelaide and South Australia.
Privacy http://www2.sahealth.ha.sa.gov.au/wps/wcm/connect/public+content/sa+health+internet/about+us/website+information/privacy
Copyright http://www2.sahealth.ha.sa.gov.au/wps/wcm/connect/public+content/sa+health+internet/about+us/website+information/copyright
Disclaimer http://www2.sahealth.ha.sa.gov.au/wps/wcm/connect/public+content/sa+health+internet/about+us/website+information/disclaimer


text:
What India can Learn from the Snowden Revelations
Big Brother is watching, across cyberspace and international borders. Meanwhile, the Indian government has few safeguards in theory and fewer in practice. There's no telling how prevalent or extensive Indian surveillance really is.
The title of the article was changed in the version published by Yahoo on October 23, 2013.
Since the 'Snowden revelations', which uncovered the United States government's massive global surveillance through the PRISM program, there have been reactions aplenty to their impact.
The Snowden revelations highlighted the issue of human rights in the context of the existing cross-border and jurisdictional nightmare: the data of foreign citizens surveilled and harvested by agencies such as the National Security Agency through programs such as PRISM are not subject to protection found in the laws of the country. Thus, the US government has the right to access and use the data, but has no responsibility in terms of how the data will be used or respecting the rights of the people from whom the data was harvested.
The Snowden revelations demonstrated that the biggest global surveillance efforts are now being conducted by democratically elected governments – institutions of the people, by the people, for the people – that are increasingly becoming suspicious of all people.
Adding irony to this worrying trend, Snowden sought asylum from many of the most repressive regimes: this dynamic speaks to the state of society today. The Snowden revelations also demonstrate how government surveillance is shifting from targeted surveillance, warranted for a specific reason and towards a specified individual, to blanket surveillance where security agencies monitor and filter massive amounts of information.
This is happening with few checks and balances for cross-border and domestic surveillance in place, and even fewer forms of redress for the individual. This is true for many governments, including India.
India's reaction
After the first news of the Snowden revelations, the Indian Supreme Court agreed to hear a Public Interest Litigation requesting that foreign companies that shared the information with US security agencies be held accountable for the disclosure. In response to the PIL, the Supreme Court stated it did not have jurisdiction over the US government.
The response of the Supreme Court of India demonstrates the potency of jurisdiction in today's global information economy in the context of governmental surveillance. Despite being upset at the actions of America's National Security Agency (NSA), there is little direct legal action that any government or individual can take against the US government or companies incorporated there.
In the PIL, the demand that companies be held responsible is interesting and representative of a global debate, as it implies that in the context of governmental surveillance, companies have a responsibility to actively evaluate and reject or accept governmental surveillance requests. Although I do not disagree with this as a principle, in reality, this evaluation is a difficult step for companies to take.
For example, in India, under Section 69 of the Information Technology Act, 2000, service providers are penalized with up to seven years in prison for non-compliance with a governmental request for surveillance. The incentives for companies to actually reject governmental requests are minimal, but one factor that could possibly push companies to become more pronounced in their resistance to installing backdoors for the government and complying with governmental surveillance requests is market pressure from consumers.
To a certain extent, this has already started to happen. Companies such as Facebook, Yahoo and Google have created 'transparency reports' that provide – at different granularities – information about governmental requests and the company's compliance or rejection of the same.
In India, P. Rajeev, Member of Parliament from Kerala, has started a petition asking that the companies disclose information on Indian data given to US security agencies. Although transparency by complying companies does not translate directly into regulation of surveillance, it allows the customer to make informed choices and decide whether a company's level of compliance with governmental requests will impact his/her use of that service.
The PIL also called for the establishment of Indian servers to protect the privacy of Indian data. This solution has been voiced by many, including government officials. Though the creation of domestic servers would ensure that the US government does not have direct and unfettered access to Indian data, as it would require that foreign governments access Indian information through a formal Mutual Legal Assistance Treaty process, it does not necessarily enhance the privacy of Indian data.
As a note, India has MLAT treaties with 34 countries. If domestic servers were established, the information would be subject to Indian laws and regulations.
Snooping
The Snowden Revelations are not the first instance to spark a discussion on domestic servers by the Government of India.
For example, in the back-and-forth between the Indian government and the Canadian company RIM, now BlackBerry, the company eventually set up servers in Mumbai and provided a lawful interception solution that satisfied the Indian government. The Indian government made similar demands from Skype and Google. In these instances, the domestic servers were meant to facilitate greater surveillance by Indian law enforcement agencies.
Currently in India there are a number of ways in which the government can legally track data online and offline. For example, the interception of telephonic communications is regulated by the Indian Telegraph Act, 1885, and relies on an order from the Secretary to the Ministry of Home Affairs. Interception, decryption, and monitoring of digital communications are governed by Section 69 of the Information Technology Act, 2000 and again rely on the order of the executive.
The collection and monitoring of traffic data is governed by Section 69B of the Information Technology Act and relies on the order of the Secretary to the government of India in the Department of Information Technology. Access to stored data, on the other hand, is regulated by Section 91 of the Code of Criminal Procedure and permits access on the authorization of an officer in charge of a police station.
The gaps in the Indian surveillance regime are many and begin with a lack of enforcement and harmonization of existing safeguards and protocols. Presently, India is in the process of realizing a privacy legislation.
In 2012, a committee chaired by Justice AP Shah (of which the Center for Internet and Society was a member) wrote The Report of the Group of Experts on Privacy, which laid out nine national privacy principles meant to be applied to different legislation and sectors – including Indian provisions on surveillance.
The creation of domestic servers is just one example of how the Indian government has been seeking greater access to information flowing within its borders. New requirements for Indian service providers and the creation of projects that go beyond the legal limits of governmental surveillance in India enable greater access to details about an individual on a real-time and blanket basis.
For example, telecoms in India are now required to include user location data as part of the 'call detail record' and be able to provide the same to law enforcement agencies on request under provisions in the Unified Access Service and Internet Service Provider Licenses.
At the same time, the Government of India is in the process of putting in place a Central Monitoring System that would provide Indian security agencies the ability to directly intercept communications, bypassing the service provider.
Even if the Central Monitoring System were to adhere to the legal safeguards and procedures defined under the Indian Telegraph Act and Information Technology Act, the system can only do so partially, as both provisions create a clear chain of custody that the government and service providers must follow – that is, the service provider was included as an integral component of the interception process.
If the Indian government implements the Central Monitoring System, it could remove governmental surveillance completely from the public eye. Bypassing the service provider allows the government to fully determine how much the public knows about surveillance. It also removes the market and any pressure that consumers could exert from insight provided by companies on the surveillance requests that they are facing.
Though the Indian government could (and should) be transparent about the amount and type of surveillance it is undertaking, currently there is no legal requirement for the government of India to disclose this information, and security agencies are exempt from the Right to Information Act. Thus, unless India has a Snowden somewhere in the apparatus, the Indian public cannot hope to get an idea of how prevalent or extensive Indian surveillance really is.
Policy vacuum
For any government, the surveillance of its citizens, to some degree, might be necessary. But the Snowden revelations demonstrate that there is a vacuum when it comes to surveillance policy and practices. This vacuum has permitted draconian measures of surveillance to take place and created an environment of mistrust between citizens and governments across the globe.
When governments undertake surveillance, it is critical that the purpose, necessity and legality of monitoring, and the use of the material collected are built into the regime to ensure it does not violate the human rights of the people surveilled, foreign or domestic.
In 2013, the International Principles on the Application of Human Rights to Communications Surveillance were drafted, in part, to address this vacuum. The principles seek to explain how international human rights law applies to surveillance of communications in the current digital and technological environment. They define safeguards to ensure that human rights are protected and upheld when governments undertake surveillance of communications.
When the Indian surveillance regime is measured against these principles, it appears to miss a number of them, and does not fully meet several others. In the context of surveillance projects like the Central Monitoring System, and in order to avoid an Indian version of the PRISM program, India should take into consideration the safeguards defined in the principles and strengthen its surveillance regime to ensure not only the protection of human rights in the context of surveillance, but to also establish trust in its surveillance regime and practices with other countries.
Elonnai Hickok is the Program Manager for Internet Governance at the Centre for Internet and Society, and leads its research on privacy.
Filed under: Internet Governance, Privacy
The views and opinions expressed on this page are those of their individual authors. Unless the opposite is explicitly stated, or unless the opposite may be reasonably inferred, CIS does not subscribe to these views and opinions which belong to their individual authors. CIS does not accept any responsibility, legal or otherwise, for the views and opinions of these individual authors. For an official statement from CIS on a particular issue, please contact us directly.
Internet Governance, Privacy
Elonnai Hickok
The Centre for Internet and Society's comments and recommendations to the: The Digital Data Protection Bill 2022
'Techplomacy' and the negotiation of AI standards for the Indo-Pacific
Demystifying Data Breaches in India
Getting the (Digital) Indo-Pacific Economic Framework Right
NHA Data Sharing Guidelines – Yet Another Policy in the Absence of a Data Protection Act
Transference: Reimagining Data Systems: Beyond the Gender Binary
Launching CIS's Flagship Report on Private Crypto-Assets
How to Shut Down Internet Shutdowns
Cybersecurity Visuals Media Handbook: Launch Event
Internet Speech: Perspectives on Regulation and Policy


text:
The Words of Cicero
Can We All Become Geniuses
George Harrison Living in the Material World 1 of 2
Son of Hades
Inside Bills Brain: Decoding Bill Gates 1of3
The Last Dance Episode V
Putin Forever
Hidden Kingdoms: Under Open Skies
Blood Of The Vikings: First Blood
Chased by Sea Monsters 2of3
The Last Dance Episode IV
Changing Planet
Land Of The Mammoth
"Video game" Sort by
Love a Bot
2017 Technology
Here's a growing trend in artificial intelligence. Dating video games and other applications let users carry on virtual relationships with computerized girlfriends ranging from career women to Japanese schoolgirls. There's even something for the ladies. How soon will there be artificial intelligence of such complexity that protecting its well-being and rights becomes a serious political and social concern? In what year will there be an app or computer program or a device that you not only love but that possibly, within the realm of believability might actually love you ...back?
Series: Mind Field Season 1
Moleman 4 Longplay
It is the year 2546. Corporations rule the world, and an agent is on a secret mission to explore the untold stories of the past. His journey leads him into a secret virtual reality where one corporation has recreated the 1980s, an era that witnessed the birth of video game development, an event in which a politically and economically restricted small European country, Hungary, had a significant role.
He discovers a strange but exciting world, where computers were smuggled through the Iron Curtain and serious engineers started developing games. This small country was still under Soviet pressure when a group of people managed to set up one of the first game development studios in the world, and western computer stores started clearing room on their shelves for Hungarian products. These developers really didn't know it was impossible, because they created games including amazing technical feats that even engineers at Commodore thought their machines weren't capable of.
Indie Game The Movie
The film, directed by James Swirsky and Lisanne Pajot, looks at the underdogs of the video game industry, indie game developers, who sacrifice money, health and sanity to realize their lifelong dreams of sharing their creative visions with the world.
This Sundance award-winning film captures the tension and drama by focusing on these artists' vulnerability and obsessive quest to express themselves through a 21st-century art form.
Jesus Camp
2006 Culture
The youngest foot soldiers for the Lord are shown in their native environment in this documentary. Becky Fischer is a children's pastor who runs 'Kids on Fire,' a summer camp for evangelical Christian children in North Dakota. Fischer believes in the political and moral importance of a Christian presence in America, and uses her camp to reinforce the religious training most of her charges are already receiving at home (the majority of the campers are home-schooled by their parents).
Using video games, animated videos, and group activities to help put her message across, Fischer encourages the kids to pray for the President and his Supreme Court appointees while urging them to help 'take back America for Christ.' For the most part, the children seem reasonably ordinary beyond the fact they pray with uncommon fervour and sometimes speak in tongues.
Along with Fischer and her cohorts, Jesus Camp features interviews with Ted Haggard, an evangelist and advisor to George W. Bush, and Mike Papantonio, a Christian talk-show host who believes the right-wing slant of many Christian evangelists is taking the church into a dangerous direction.
Are Video Games Really That Bad
The video game industry is a global phenomenon. There are over 1.2 billion gamers across the planet, with sales projected soon to pass $100 billion per year. But their very popularity fuels the controversy that surrounds them. They frequently stand accused of corrupting the young - of causing violence and addiction. But is this true? The scientific community is deeply divided". Some are convinced that video games incite aggression. Others insist they have no effect whatsoever on real-world violence. But away from the controversy, there is a growing body of evidence that suggests video games may help keep the brain sharp, and could soon revolutionise how we combat mental decline as we age.
George Harrison Living in the Material World
2011 History
Hidden Kingdoms
2014 Nature
Blood of the Vikings
Chased by Sea Monsters
Prehistoric America
First Life
2010 Science


text: Q: How do I start tracking why one particular previous wifi connection can't connect after upgrade from 21.10 to 22.04? I have 5-7 secured wifi networks that I connect to throughout the week.  They all worked with no problem after my upgrade to 22.04 back in April.  One in particular will not connect at all and just says "connecting" and goes no farther.  All the settings are set to "Automatic" and always have been. My work (Windows) laptop and my UbPorts Pixel3 still connect using the same credentials as always so nothing in the network should have changed.  I have tried forgetting the network and re-entering the password with no success.  Can anyone point me to the proper steps to figure out what is going on behind the scenes and maybe get this connection fixed?

redpajama_set_name: RedPajamaStackExchange


text:
Q: Using SketchFlow to prototype MS Surface Applications We're doing mockups/prototyping on a MS Surface device and I wonder if anyone has succeeded in using SketchFlow for this. The problem that I see is that the code generated by the tool uses normal WPF controls (Button, etc.) instead of the contact aware surface counterparts (SurfaceButton) which means that they won't work nice on the surface unless you also use a mouse.
Additionally, it would be nice if it was possible to hook in to other gesture events to trigger sketchflow transitions. Like the pinch gestures to switch page etc.
Has anyone had any success with prototyping for Surface using Sketchflow. If so, how did you do it?

A: You could write a trigger or behavior that would handle the other gesture events you mention to navigate around the SketchFlow player that would be re-usable, and should enable what you are suggesting.
As for the controls, I am not very familiar with surface development, but you might also be able to create a behavior that when attached adds some sort of surface ability, like clickability to the visual object.
Happy to help if I can be of any assistance.


Moving house, unsurprisingly, is one of the major changes many people experience in life and often more than once. It can be both an exciting and stressful time for children, who may have never gone through it before. They may have to say goodbye to favourite pastimes, much-loved playtime haunts and well-known neighbours.
show or describe to children what their new room will look like. Drawing the layout, creating cut-outs of their furniture and helping them colour in the walls will allow them to imagine their new space.
The big move is a turning point in everyone's life. A chance to turn over a new leaf and try something new. Let the positives outweigh the negatives and allow the kids to join in and get excited about the new chapter of your lives. We hope these tips help make the transition easier!
As always, if my husband or I can help you with any of your property goals, whether buying or selling, renovating or investing, please feel free to contact our team as we are always happy to help.
NYE With the Family on Sydney's Cockatoo Island – TICKETS NOW ON SALE!
Is Your Child Primary School Ready?


Dear friends in Christ, what a day this is! What a feast! What a text! What a beautiful picture of the heavenly realms that God gives through His apostle John to you and me. We see here the end promises of Jesus to those who are blessed by the Lord with the gift of faith. We see in Revelation a wondrous picture as the saints, angels, elders, the four living creatures--all are active in worshiping God together in blissful paradise. Indeed, heaven is for real--and this is what God wants us to know about it.
But this picture that we are given in Revelation is hard to believe--it's hard to fathom that such perfect bliss/joy could really exist--or ever truly be ours. We look at our own situation in this life: we are wounded and hurting--scarred by our own sin and misdeeds, while also bearing the marks of others' cruelty against us in our bodies, minds, and spirits. Our relationships are often tattered--hanging on by a mere thread. We are consumed with worry and doubt as we are faced with sickness and dying. We are persecuted and hated for being Christians who actually believe the simple words of Scripture and hold that God's Word is absolute. It seems unbelievable that the great reward Jesus promises--the paradise that John describes in our text--could ever belong to us.
Indeed, we look at ourselves: we are ever prideful and looking out for number 1--we are not poor in spirit or meek. We hunger and thirst, but often not for God's righteousness, but rather to satisfy our lust for the pleasures of this world and life. It seems that we are in constant and deepest mourning due to the suffering and death that plagues the world as everywhere we look there are hurting and dying people. We look at ourselves and think that the beautiful picture of all the saints gathered around the throne of God MUST not--COULD not--include us. If God knows just half the things we have done--He'll never let us in! How could He? Why would He?
Beloved, we find ourselves in this life torn between faith and doubt, the sacred and profane--as the good that we want to do is not what we tend to do, while the evil we do not want to do is usually what we end up doing. "Wretched man that I am! Who will deliver me from this body of death" and give me the heavenly glory that John describes so elegantly?
Dear friends, lowly sinners' only hope is in Christ Jesus--who comforts those who mourn--satisfies the need for righteousness--delivers mercy--adopts into His family as sons of God--and who bestows the kingdom of heaven to all those who believe. And you can know absolutely--without a doubt--that all of that belongs to you and more because of what John records for us in Revelation. An angel came with the seal of the living God and he called to the four angels who were about to bring destruction on the earth to hold--to wait--until all of God's servants could have the seal of God upon their foreheads--the seal of His protection and might--to preserve them from the calamity to come.
"But how do I know if I have been sealed or not?" you may ask. Listen to the number of people that John hears. 12 thousand from the 12 tribes of Israel, which equals 144 thousand in total. This number symbolically represents ALL the people of God for all time--all the faithful--from Adam to Noah to Moses to David to Peter to John to Luther to YOU!
Now Jesus tells us plainly that the life of the Christian in this unbelieving world will not always be easy. This world is broken with sin, even as we ourselves are. So in our constant struggle we need to be blessed. The Holy Spirit fortifies us through the Word and the Sacrament. You were sealed, dear friends, at your Baptism for the kingdom of heaven. The Holy Spirit came and put upon your forehead the mark of Jesus' cross as you were baptized into the triune name of the Holy God--Father, Son, and Holy Spirit. You are a part of the "great multitude that no one can number, from every nation, from all tribes and peoples and languages, standing before the throne and before the Lamb, clothed in white robes, with palm branches..."
"For salvation belongs to our God who sits on the throne, and to the Lamb!" He eulogizes you--blesses you with fine speech--as He speaks to you of mercy and forgiveness that is given through faith in Jesus Christ. The Lord bestows His blessed righteousness and life and salvation upon you who are unworthy! But you are MADE worthy by Him! The Lord has taken you and washed you clean in the blood of the Lamb. You are now clothed in the white robe of Christ's righteousness. The filthy garments of your sinful flesh--the wretchedness of your supposed good works--all cleansed--all made new and pure and holy--by being immersed and drowned in the blood of Jesus.
Now...is THIS hard to believe? Absolutely, yes! But, by God's grace in the Holy Spirit--you DO believe. As miserable and desperate as people are in this life--plagued with sin and crushed by evil--as weighted down with guilt and despair and loneliness as you may be now--remember who dwells with you. "He who sits on the throne will shelter [you] with His presence. [You shall hunger no more, neither thirst anymore; the sun shall not strike [you], nor any scorching heat. For the Lamb in the midst of the throne will be [your] shepherd, and He will guide [you] to springs of living water, and God will wipe away ever tear from [your] eyes."
You have been brought through the great tribulation of this life and death by He who has conquered it all for you--the Lord Jesus Christ. The Lamb who was slain is your Good Shepherd who leads you to the springs of the water of life that flow from His pierced side on the cross. No matter what you may face--what you may suffer--what you may endure--heaven is for real--and it's already yours--as a free gift--paid for by the blood of Jesus. Hard to believe? Sure, but remember, "Amen! Blessing and glory and wisdom and thanksgiving and honour and power and might be to our God forever and ever! Amen." The blessing is His to give--and He has given it to you by filling your heart with faith in Jesus. Thanks be to God in Christ Jesus. Amen.


In a recent market study published by Transparency Market Research, the global glass fibers market is said to be expected to reach a valuation of US$14 mn by 2020, increasing from US$8 mn in 2013. This will translate into a compounded annual growth rate of 8.40% therein. The report is titled "Glass Fibers Market - Global Industry Analysis, Size, Share, Growth, and Trends and Forecast 2014 - 2020" and is available for sale on the company's website.
Glass fibers are materials that consist of numerous extremely minute fibers of glass. Glass fibers exhibit properties of light weight, high tensile strength, and high sturdiness. Due to their high bulk strength and light weight, glass fibers are favored in many applications over even metals.
The report says that the global glass fibers market is largely driven due to the usability of the material across a wide spectrum of applications. This includes wind turbines, transportation, building and construction, and consumer goods, among others. The exponential growth of practically all application areas of glass fibers has tremendously boosted the growth of the glass fibers market. Glass fibers are used on a large scale in fiber-reinforced plastics.
Glass fibers are suitable for a host of applications due to their high structural strength and resistance to impact. Particularly in wind turbine operations, the lightness of turbines including consisting of fibers facilitates smooth power generation; in automotive design, lightness of the vehicle is important for reducing greenhouse gas emissions. Thus, glass fiber reinforced plastics are commonly used in wind turbines and automotive components.
Of all the glass fiber types, E-class glass fibers display a clear dominance over other glass fiber type segments. This segment currently accounts for a share of more than 80% in the global market due to the low cost, high modulus, and high tensile strength of E-class glass fibers. Other glass fiber types such as S-class, D-class, and C-class are more expensive to manufacture, but outdo E-class fibers in matters of performance. This is the reason why these glass fibers are collectively known as performance glass fibers and are commonly used for technical applications.
Application-wise, building and construction is the largest application segment of this market. Glass fibers are used for residential and non-residential insulation applications. Glass fibers are also used in the fabrication of bathroom fittings and indoor furniture; the material is increasingly being used as an alternative to timber, aluminum, steel, and concrete for these applications.
In 2013, Asia Pacific stood as the largest regional market for glass fibers, accounting for a share of 45% in the global market. The easy availability of labor at low wages and readymade manufacturing facilities in China and India is the reason for this.
The report mentions and profiles top companies in the global glass fibers market. These are Owens Corning Corporation, Jushi Group Co. Ltd., Johns Manville Corporation, PPG Industries Inc., Nippon Electric Glass Co. Ltd., and AGY Holding Corporation.


Something is WRONG with our nation's Welfare System!!!!!!! Abigail and I are standing in line at the Dollar Tree yesterday. The young couple in front of us have their cart filled to the top with packaged junk food, absolute garbage -- brownies, cookies, fruit punch juice boxes, candy, jerky, and lots more. Nothing nutritious; nothing healthy. Their appearance leaves something to be desired -- baggy sweats, unwashed hair, and flip flops. The total is over $130 and they pay for it with a Food Stamp debit card. Seriously. Seriously? Seriously! In sharp contrast is the young man in line behind me who is in a wheelchair and pays for his items with CASH. He is neatly dressed, wearing a polo shirt with a corporate logo on it, so I assumed he was employed. He comments on Abigail's good behavior and wishes me a "Good Day!"
Tuesday night we eat the first beans from our garden. I hope there will be lots more when we come back from vacation. =) Maybe some tomatoes, too.
Leaving for a family vacation early, early Saturday morning. We are going to ALASKA! The laptop is coming with us but I'm not going to do any blogging. I'll be back the last week of June.


Looking for crispy chips to enjoy with guacamole or hummus? I have got you covered!
These chips are thin and crispy with a delicate cheesy flavor, plus they come with roasted sunflower seeds and pine nuts. Let's do it!
The batter is easy. You start by whisking together rice flour, tapioca flour, and flax seeds. Then for flavor, you add nutritional yeast for cheesiness, onion powder, garlic powder, and a pinch of chili for spiciness.
The addition of coconut oil is essential for getting perfectly crispy chips. So for those of you who are avoiding oil, I'm afraid I have no substitute to recommend.
The key to getting thin and crispy tuiles is to spread the batter very thinly on the baking sheet. Then bake until golden brown.
Right after baking, the tuiles are still soft but will crisp up as they cool. Finally, simply break it into small chips and enjoy!
These tuiles are thin, crispy, cheesy, and have a nutty flavor. It's perfect to have with guacamole, salsa, hummus, or just as a snack!
Thin and crispy savory tuiles that are cheesy and packed with roasted sunflower seeds and pine nuts. Perfect with guacamole, salsa, or cold dips!
Preheat oven to 350°F (175°C) and line a baking sheet with a silpat or parchment paper.
In a small bowl, combine the white rice flour, tapioca starch, nutritional yeast, ground flaxseeds, onion powder, garlic powder, ground chili, and salt.
Pour in the almond milk and melted coconut oil. Whisk until fully combined and let it rest for 5 minutes. After 5 minutes, add the sunflower seeds and pine nuts, and stir to combine.
Transfer half of the batter on the prepared baking sheet and spread it as thinly as possible. At this point, you can top with more seeds, this is just for the look.
Bake for 8 minutes, then turn off the oven and leave it for another 4 minutes with the door slightly opened.
Remove from the oven and let cool completely before breaking into chips. Repeat with the other half of the batter.
Tuiles will keep for up to 4 days at room temperature, stored in an airtight container.
These were delicious but the consistency of the batter and the length of time I needed to cook mine was way different. There was no pour factor to my batter. It was thick and more of a dough than a batter. I was able to spread it out onto a silpat with a pastry knife. The bake time was more like 13 minutes for me. I'm going to try and add more Almond Milk to give the batter more liquid consistency and see what happens. But again…the end result was delicious. Thank you. Any suggestions would truly be appreciated.
Did you use the exact same flours? I make this recipe regularly and the batter always ends up quite thin.


Having A Blocked Drain System Is Not Something You Can Predict. In addition to posing health risks, the undrained water in the sink (or bath) and flooding can cause air pollution. Regular maintenances can avert this nightmare.
A build - up of debris such as cooking oil, fruit seeds, grain, or intrusive mature tree roots can cause your drains to clog. Even if blockages don't occur in your own pipes, they can happen in the larger main lines q leading to problem's for a number of people.
1. Minor clogs can be fixed with just a plunger.
2. Clear the debris from under your bathtub stoppers a couple of times per week. Before you put the stopper back in its place, make sure it's well cleaned.
3. If You Lose Hair Easily, Make Sure You Place A Barrier (Mesh) On The Drain Hole Before You Wash Your Hair In The Bathtub Or Sink. Just as you prevent food going down the sink in the kitchen, you should ensure hair doesn't go down your bathroom pipes.
4. Brush your hair before showering or bathing to collect loose hair on your brush instead of in your drain.
5. You should also install grates to cover your drains. When Getting Your Drains Cleaned, Use A Drain Cleaner That Is Anti - Bacterial And Which Is Not Corrosive.
6. Plant flowers and trees away from your pipes to prevent their roots growing into your drains.
7. Benefit from periodic servicing and inspections done by a drainage company even if you don't call them and you can do this by going into a contract with them yearly. Drainage Stoke offers this kind of contract to people in and around Stoke. Educate family members and friends about the maintenance of your home's drains.
8. Cease using chemical cleaners. They can cause corrosion and serious long - term damage.
9. Do Not Throw Rubbish In Your Drains. Don't throw stuff into it.
10. Avoid letting the following substances go into the drain grease, oil, fat, coffee, meat, rice, gum, hair, condoms, medication, cosmetics and similar items.
11. Drains are designed for water q nothing else q except for the toilet, which is able to handle water plus human wastes.
12. You Can Use Your Wire Coat Hanger As A Hook When You Straighten It And Then Pass It Into Your Drain To Remove Debris That Accumulates There.
13. You can prevent the build - up of grease in the drain by pouring hot salty water down it.
14. There are many maintenance tips for your drains, these are just a handful; a few of which are alternative solutions. But, just ensure you avoid acidic solutions.
If you currently have drainage problem's in your home and nothing on the list has worked so far, don't force it, otherwise you could worsen the situation. Don's worry about it and call a plumber to have a look. If you happen to be in Stoke then your best option will probably be Drainage Stoke technicians.
I can not thank Drainage Stoke enough for their friendly, helpful service. They fixed my bloked shower in Stoke quickly and cheaply.
Drainage Stoke are a fantastic Stoke based drainage company that fixed my blocked shower and sink with in the day. Thankyou so much.
Email or phone today to contact Drainage Stoke for drainage experts in Stoke.


I'm no expert in Photoshop, so fiddling around with the crisp and clean source image to make it look old, blurry and deliberately overexposed, was quite a challenge. I'm sure experts would know the steps necessary to achieve that. I, on the other hand, just clicked around frenetically on all kinds of effects until I somehow ended up with the image above.


text:
(Back to Article Homepage)
Molecular Biology Databases on the Internet
(Biotechniques Article - September 1996)
Does the Net measures up to the hype? A lot of people think the Net is full of silly stuff (Internet Doom comes to mind), and that you can't do serious things on it. This article introduces some of the most useful molecular biology tools on the internet, the availability of genomic databases.
Most of us have heard of the GenBank or SWISS-PROT databases. Many of us use them on a daily basis for finding sequences of interest or designing PCR primers. These databases are commonly accessed from CD-ROMs, and packaged with sequence analysis software. Usually updated quarterly, these packages present a useful and necessary resource to the molecular biologist. Several drawbacks exist, however, including cost, lack of continuous updates, as well as limited and varied search engines. While the outright replacement of these functions by tools available on the World Wide Web (WWW) is unlikely for heavy users due to potential delays in recieving results, the WWW now offers services that address all the aforementioned drawbacks besides performing nearly all the tasks that these commercial packages offer.
The expanding resources on the WWW in this area include search and analysis tools for: proteins, nucleic acids, multiple sequence alignments, PCR primers, gene features and secondary structures in proteins. Due to the brevity of this column, I will summarize the tools available at some of the best starting points on the web. The means of interaction with these tools on the WWW vary greatly. Most of these sites accept data submission directly from the browser, through a "forms" interface. This means that you type (or cut and paste) the sequence data directly into electronic fill-in-the-blank forms in the browser window, and then click a submit button. If you do not have access to a forms-capable browser such as Netscape or Internet Explorer, alternate types of data submission include email, ftp, and even some gopher interfaces. Quick types of searches may be set up to display the results on a web page, whereas more lengthy types of searches may send you the results by e-mail. On-site instructions and documentation are quite good and make these sites very user friendly.
A good place to start a tour of molecular biology services on the WWW is the National Center for Biotechnology Information (NCBI, http://www.ncbi.nlm.nih.gov/). The NCBI site contains several major resources. The most well known among these is probably GenBank. GenBank is the NIH genetic sequence database, an annotated compilation of all publicly accessible DNA sequences (835,000 as of June 1996). GenBank at NCBI is part of the International Nucleotide Sequence Database Collaboration, in conjunction with the DNA DataBank of Japan (DDBJ, http://www.ddbj.nig.ac.jp/) and the European Molecular Biology Laboratory (EMBL, http://www.embl-heidelberg.de/). These organizations exchange data daily and maintain nearly identical sequence databases.
Searching GenBank for sequences of interest is a remarkably simple process. By following the links from the NCBI page to the GenBank search page (http://www2.ncbi.nlm.nih.gov/genbank/query_form.html), you will be presented with a simple search utility. The form boxes on this page allow you to enter descriptive information about the sequence you are seeking. For example, by entering "HIV" on the first line, "gp120" the second line and clicking on the "Run Query" button, the first one hundred GenBank sequences for HIV gp120 will appear on the next screen. Additional features of this interface allow for field restrictions as well as use of the "or" or "but not" operators. In general, this is how most sequence retrieval pages function and it is a good example of the simplest type of sequence analysis tool available on the web.
The WWW Entrez Database (http://www3.ncbi.nlm.nih.gov/Entrez/) allows the user to access three databases: the National Library of Medicine's MEDLINE database, the NCBI protein database, and the NCBI nucleotide database (GenBank). The MEDLINE subset database is compiled from journal publications, and genetic sequences located in this database have the added benefit of being linked to the abstract of the journal article that first reported them. The Protein and Nucleotide entries in Entrez come from several databases: GenBank, EMBL, DDBJ, PIR, SWISS-PROT, PRF, and PDB. Cross-referencing attempts have been to reduce sequence duplication.
The Basic Local Alignment Search Tool (BLAST) Gateway (http://www.ncbi.nlm.nih.gov/BLAST/) is another means of accessing the databases at NCBI. BLAST searches can be performed at a basic or advanced level. The basic search permits the choice of a search program and uses default filtering parameters. Advanced searches allow the selection of various additional filters. There are five different BLAST programs available, which allow everything from a simple sequence homology search, to complex comparisons of the six-frame translations of a nucleotide query sequence against the six-frame translations of a nucleotide sequence database. The interface is relatively simple, with the requirement that the sequence be in FASTA format (http://www.ncbi.nlm.nih.gov/BLAST/fasta.html), which is essentially the standard IUB/IUPAC amino acid and nucleic acid codes. Results are e-mailed to users in either a text format or HTML. Options for advanced searches allow the results to include histograms of scores for each search, set statistically significant thresholds, limit the number of alignments considered, specify the use of alternate scoring methods (matrices), or limit analysis to one strand among other options.
Other NCBI resources demonstrate additional uses of genetic information. The first is the OMIM: Online Mendelian Inheritance in Man. This database is a catalog of human genes and genetic disorders and was developed for the WWW by NCBI. In this database you will find pictures and references, as well as text-based information. It also contains copious links to NCBI's Entrez database of MEDLINE articles and sequence information. The NCBI Taxonomy database contains information about all the organisms present with at least one sequence in the genetic databases. This tool, like OMIM, demonstrates the power of interlaced or cross-referenced data, combining taxonomy with raw genetic information. Other databases available for searching through the NCBI site include: dbEST: Database of Expressed Sequence Tags, dbSTS: Database of Sequence Tagged Sites, and the MMDB: Molecular Modeling Database.
The European Molecular Biology Laboratory (http://www.embl-heidelberg.de/) is another great site for accessing genomic databases. The European Bioinformatics Institute (EBI, http://www.ebi.ac.uk/), an EMBL subsidiary, offers the Nucleotide Sequence Database--a comprehensive database of DNA and RNA sequences extracted from scientific literature, patent applications, or through direct submission from researchers world wide. This site offers a similar interface for access to information that is nearly identical to that found in GenBank.
EBI is also the home of the SWISS-PROT Protein Sequence Database (http://www.ebi.ac.uk/ebi_docs/swissprot_db/swisshome.html). The SWISS-PROT Protein Sequence Database contains protein sequences (52,205) produced from translations of EMBL Nucleotide Sequence Database sequences. It contains extensive notes and is cross-referenced to the EMBL nucleotide sequence database and the PROSITE pattern database (described below). The BLITZ ultra-fast protein database search (http://www.ebi.ac.uk/searches/blitz.html) found at this site allows the user to select the number of alignments, number of hits, gap and substitution penalties while entering data in a simple browser cut and paste format.
PROSITE pattern searches (http://www.ebi.ac.uk/searches/prosite.html) at EBI allow a comparison of a given protein sequence with all protein patterns stored in the PROSITE pattern database. Knowledge of the known protein patterns or motifs in your sequence can be invaluable in finding it's biological function. The site includes much information about how to format your submission, which can be accepted by the browser forms, or by email.
Another Sequence Data Analysis page at the EBI site features FASTA homology searches (http://www.ebi.ac.uk/htbin/fasta.py?request). This powerful tool allows the user to set sensitivity, number of matched sequences, number of aligned sequences along with selecting a database to which the query is submitted.
One of my favorite web sites for protein analysis is the PredictProtein server (http://www.embl-heidelberg.de/predictprotein/predictprotein.html) at EMBL. This automated utility functions from amino acid sequences submitted by browser or email. By performing multiple sequence alignments, PredictProtein calculates secondary structural interactions, solvent availability for individual residues, and the position of transmembrane elements and helices. Three major features of this algorithm are available: (1) fold recognition by prediction-based threading using data obtained from proteins with remote homologies (sequence identity 0-25%) to the sequence of interest; (2) prediction of structures for helical transmembrane proteins; (3) an evaluation of prediction accuracy, utilizing predicted and observed secondary structures with a results breakdown per-residue or per-segment.
BEAUTY (BLAST Enhanced Alignment Utility) is an enhanced version of the NCBI's database search tool. BEAUTY, which can be found at Baylor College of Medicine (http://dot.imgen.bcm.tmc.edu:9331/seq-search/Help/beauty.html), includes additional results into BLAST searches. It can, for example, identify conserved domains, incorporate data on family membership and add the locations of any annotated domains. These BLAST additions yield significant power to the search utility, particularly when the user is interested in finding regions of weak homology.
The Genome Database (GDB, http://gdbwww.gdb.org/) at Johns Hopkins University School of Medicine, is the cyberspace version of the Human Genome Project. This database (GDB 6.0) maps introns, exons, gene families, regulatory elements and gene products. All of these data types are queryable, and on-line-users are allowed to submit additional data as updates or annotation. This is a very user friendly database, and represents an innovation in object-oriented programming.
To find even more genomic data sites, take a look at Pedro's BioMolecular Research Tools (http://www.public.iastate.edu/~pedro/research_tools.html). Pedro has amassed a huge collection of WWW links for genomic search and analysis sites, along with other molecular biology tools. The newsgroup "bionet.software.www" also lists new sites on the WWW of interest to biologists.
Another great site is sponsored by the Human Genome Center at Baylor College of Medicine. The BCM Search Launcher (http://dot.imgen.bcm.tmc.edu:9331/seq-search/seq-anal-resources.html) is an attempt to organize molecular biology related search and analysis services available on the WWW by function through a single access point for related searches. For example, a single page allows access to most protein databases and searches available world wide. This site is a great example of the power of the internet.
These unique resources and others like them are becoming increasingly important and useful for molecular biology research. They are worth spending the time to learn to use effectively, and more than justify infrastructure investments to provide adequate internet connections in a molecular biology laboratory. Plus, with enough connections the whole lab can play Internet Doom (http:// ? ). Enjoy the web!
If you have any comments regarding this page please contact:
David M. Sander, Ph.D.
(david.sander@virology.net )
Don't forget to sign the Sign our Guestbook!
Article Homepage | Home | Table of Contents | Submit a Site | Search
Tulane University | Garry Lab Contact Info | FAQ | Garry Lab Home | Graffiti Wall | Tulane Medical Center
© D. Sander 1995-2007. Established 5/95.