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# Caging plant hormone with weak intermolecular interactions

Shyamlee Tiwari

M.Sc. I year, Guru Ghasidas Vishwavidalaya, Koni, Bilaspur, Chhattisgarh 495009

Dr. Apurba Lal Koner

Assistant Professor, Chemistry, Indian Institute of Science Education and Research, Bhopal Bhopal Bypass road, Bhauri, Bhopal 462066

## Abstract

Titration of Cucurbit[7]uril with thiochrome and hormones has been performed to solubilize and stabilize the water insoluble hormones and used them in bio-medical applications. Fluorescence and NMR spectroscopic techniques were employed to check the binding of hormone with synthetic macrocyclic host cucurbit[7]uril and the purity of synthesized compounds respectively. The concept behind the research was based on the reversible and competitive binding of a fluorescent dye and the substrate to a macrocyclic host. Therein, binding of the substrate or product to the macrocyclic receptor has been coupled to the displacement of a fluorescent dye. Frequently, the inclusion of a fluorescent guest into the inner cavity of a macrocyclic host is accompanied by changes of the fluorescence properties of a dye. For example, fluorescence quenching or fluorescence enhancement by complex formation with the macrocycle may be observed, which allows for the determination of the binding constant of the fluorescent dye. Addition of another guest, which binds more strongly to the macrocycle, will compete with the fluorescent dye for the macrocyclic cavity and displace the fluorescent dye, whereupon the fluorescence properties of the free dye in solution are regenerated. The resulting “supramolecular tandem assays” exploit the dynamic binding of a fluorescent dye with a macrocyclic host in competition with the binding of the substrate.

Keywords: cucurbit[7]uril, glycolurils, thiochrome, auxin, melatonin, encapsulation,

## Abbreviations

Abbreviations
 CB7 Cucurbit[7]uril NMR Nuclear magnetic resonance Å Angstrom IAA Indole-3-acetic acid Trp Tryptophan UV Ultraviolet nm nanometer NaOH Sodium hydroxide mL milliliter g gram HCl Hydrochloric acid ℃ Celsius rpm Rotation per minute

## INTRODUCTION

In 1905, Behrend and co-workers characterized the condensation products of glycoluril and formaldehyde under strongly acidic conditions as “white, amorphous compounds, which are weakly soluble in dilute acid and base and absorb large quantities of water without loosing their dusty powdery character”. One of those products were found to contain “at least three molecules of glycolurils”, condensed with twice as many formaldehyde units, thereby corresponding to the formula C18H18N12O6. More than a century later, this characterization of what was likely a mixture of cucurbit[n]uril. In 1981, Mock and co-workers revisited Behrend’s experiments and upon complexation with calcium sulfate, successfully crystallised a hydrated macrocyclic bearing six glycolurils units linked by twelve methylene bridges and interacting with the calcium cations via its two carbonylated rims. The authors named the structure “cucurbituril” for its resemblance to “a gourd or a pumpkin” (which belong to the Cucurbitaceae family). Because of their exceptional recognition properties in aqueous medium, these pumpkin-shaped macrocycles have been generating some tremendous interest in the supramolecular community.[1] They have also become key units in various self-organizing and stimulus controlled assemblies, as well as in advanced materials and drug carriers. CB[n]s bear two hydrophilic carbonylated rims and a hydrophobic cavity. Their total depth is 9.1 Å, if one includes the van der waals radii of the oxygen atoms, and the depth of the cavity is 7.4 – 7.8 Å, if one considers the separation between two planes of local electrostatic potential minima at both portals.[2]

When guest molecules are noncovalently encapsulated inside water-soluble macrocyclic container compounds such as cucurbiturils, a modification of their chemical and physio-chemical properties always occurs owing to the altered microenvironment as well as the confinement and isolation of the guest.[3] Frequently, the complexation of the guest has beneficial effects on its aqueous solubility, because the encapsulation reduces the tendency of the guest to undergo aggregation or unspecific adsorption. Further, the complexation may enhance the thermal, as well as photochemical, stability of a guest by isolating it from the aqueous bulk and thereby preventing bimolecular reactions – in the simplest case, oxidation by molecular oxygen. [4]

Melatonin is a hormone that regulates the sleep-wake cycle. It is primarily released by the pineal gland. In animals (including humans), melatonin is involved in synchronizing the circadian rhythm including sleep-wake timing, blood pressure regulation and seasonal reproduction. Many of its effects are through activation of the melatonin receptor, while others are due to its role as an antioxidant. In plants, it functions to defend against oxidative stress.

Melatonin

Auxins were the first of the major plant hormones and is present in all parts of a plant, although in very different concentrations. The pattern of auxin distribution within the plant is a key factor for plant growth, its reaction to its environment, and specifically for development of plant organs (such as leaves and flowers). It is achieved through very complex and well coordinated active transport of auxin molecules from cell to cell throughout the plant body- by the so called polar auxin transport.

Auxin (IAA)

Thus, a plant can (as a whole) react to external conditions and adjust to them, without requiring a nervous system. On the molecular level, all auxins are compounds with an aromatic ring and a carboxylic acid group. The most important member of the auxin family is indole-3-acetic acid (IAA), which generates the majority of auxin effects and is the most potent auxin. Auxins promote cell elongation, inhibit growth of lateral buds (maintains apical dominance). They are produced in the stem, buds and root tips. Auxin also promotes cell elongation. Auxin moves to the darker side of the plant, causing the cells there to grow larger than corresponding cells on the lighter side of the plant. This produces curving of the plant stem tip toward the light, a plant movement known as phototropism.

Fluorescent indicator displacement method for determining binding constants of analytes to macrocyclic hosts and its transfer to supramolecular tandem assays. Upon formation of the macrocyclic dye complex either fluorescence quenching or fluorescence enhancement and the addition of a more strongly binding competitor will restore the fluorescence properties of the free dye. Similarly, thiochrome is fluorescent but addition of water-soluble CB7 enhances the fluorescence intensity. The rotation of thiochrome inside CB7 is restricted and addition of hormones causes displacement assays.

## Background

Fluorescence quenching refers to any process that decreases the fluorescence intensity of a sample. A variety of molecular interactions can result in quenching. These include excited-state reactions, molecular rearrangements, energy transfer, ground-state complex formation, and collisional quenching. Fluorescence quenching has been widely studied both as a fundamental phenomenon and as a source of information about biochemical systems. These biochemical applications of quenching are due to the molecular interactions that results in quenching. Both static and dynamic quenching require molecular contact between the fluorophore and quencher. In case of collisional quenching, the quencher must diffuse to the fluorophore during the lifetime of a excited state. Upon contact, the fluorophore returns to the ground state, without emission of a photon. In general, quenching may occur without any permanent change in the molecules, that is, without a photochemical reaction. In static quenching, a complex is formed between the fluorophore and quencher and this complex is non-fluorescent. For either static or dynamic quenching to occur the fluorophore and quencher must be in contact. The requirement of molecular contact for quenching results in the numerous applications of quenching. For example, quenching measurements can reveal the accessibility of fluorophores to quenchers.[5]

Quenching of fluorescence is, when a fluorophore (F) and a quencher (Q) are creating a non-fluorescent complex (FQ) before excitation of F. The chemical equation therefore is:

$F\;+\;Q\;\leftrightarrow FQ$

The chemical equilibrium (KS) between the fluorophore, the quencher and the complex FQ is formed by the law of mass action and equal to the Stern-Volmer constant (KSV). There [FQ] stands for the concentration of the complex FQ, [F] for the concentration of the loose fluorophore and [Q] for the loose quencher.

KSV = Ks = [FQ]/[F][Q]

The Stern-Volmer equation describes the dependence of the fluorescent intensity of a fluorescent dye on the concentration of an quencher. It was created by two physical chemists Otto Stern and Max Volmer in 1919.

F0/F = 1 + KSV . [Q]

where, F0 is the fluorescent intensity of a fluorescent dye without the quencher

F is the fluorescent intensity of a fluorescent dye with the quencher

KSV stands for the Stern-Volmer constant

[Q] is the concentration of the quencher.

The Stern Volmer plot

Melatonin

 Synonyms N-acetyl-5-methoxytryptamine Bioavailability 30-50% Metabolism Liver via CYP1A2 mediated6-hydroxylation Metabolites 6-Hydroxymelatonin, N-acetyl-5-hydroxytryptmine, 5-methoxytrptamine Elimination half-life 30-50 minutes Excretion kidneys Formula C13H16N2O2 Molar mass 232.283 g/mol Melting point 117℃

The pineal organ of all vertebrates synthesizes and secretes melatonin in a rhythmic manner due to the circadian rhythm in the activity of arylalkylamineN-aceytltransferase (AANAT)- the rate limiting enzyme in melatonin synthesis pathway. Night-time increase in AANAT activity and melatonin synthesis depends on increased expression of AANAT gene. In mammals, only one AANAT gene is expressed. The activity of AANAT enzyme is regulated by the degree of expression of AANAT gene which exhibits diurnal rhythm in its expression in the pineal gland of majority of mammals resulting in more than 150 fold increase in AANAT gene expression during night time.[6]

When eyes receive light from the sun, the pineal gland’s production of melatonin is inhibited and the hormones produced keep the human awake. When the eyes do not receive the light, melatonin is produced in the pineal gland and the human becomes tired.  (https://en.wikipedia.org/w/index.php?title=Melatonin&oldid=914796755)

Biosynthesis of Melatonin

Biosynthesis of Melatonin

## Auxin

Indole-3-acetic acid (IAA), the most important natural auxin in plants, is mainly synthesized from the amino acid tryptophan (Trp). Auxin has long been recognized as a hormone essential for almost every aspect of plant growth and development. It is present in all parts of a plant, although in very different concentrations. The concentrations in each position is crucial developmental information, so it is subject to tight regulation through both metabolism and transport. The result is the auxin creates “patterns” of auxin concentration maxima and minima in the plant body, which in turn guide further development of respective cells, and ultimately of a plant as a whole. The dynamic and environment responsive pattern of auxin distribution within the plants is a key factor for plant growth. It is achieved through very complex and well -coordinated active transport of auxin molecules from cell to cell throughout the plant body by the polar auxin transport. Thus, a plant can (as a whole) react to external conditions and adjust to them, without requiring a nervous system.

Five naturally occurring auxins in plants include:-

Naturally occurring auxins

Biosynthesis of Auxin:-

Biosynthesis of Auxin

## Fluorescence Spectroscopy

Fluorescence spectroscopy (also known as fluorimetry or spectrofluorometry) is a type of electromagnetic spectroscopy that analyses fluorescence from a sample. Device that measures fluorescence are called fluorometers.

Molecules have various states referred to as energy levels. Fluorescence spectroscopy is primarily concerned with electronic and vibrational states. Generally, the species being analysed has a ground electronic state (a low energy state) of interest, and an excited electronic state of higher energy. Within each of these electronic states there are vibrational states. In fluorescence, the species is first excited by absorbing a photon, from its ground electronic state to one of the various vibrational states in the excited electronic state. Collisions with other molecules cause the excited molecule to lose vibrational energy until it reaches the lowest vibrational state from the excited electronic state. This process is often visualized with a Jablonski diagram.[7]

The Jablonski diagram features the energy levels within a molecule where valence electrons could be excited. Light of specific wavelength interacts with an electron and causes its excitation to a higher energy level. Excited states are short-lived, so there are two modes for the release of excess energy. It could either occur through non-radiative transitions or through emission of light quanta. The naming of the electronic states is based on the spin angular momentum configuration of each state. S0 is the singlet ground state of the molecule; S1 is the first excited singlet state; S2 is the second excited singlet state; T1 is the first excited triplet state. The radiative transitions are absorption, fluorescence, phosphorescence and the non-radiative transitions include vibrational relaxation, internal conversion and intersystem crossing Adapted from Principle and application on pharmaceutical analysis. ISRN Spectroscopy. 2013. 1-12.10.1155/2013/230858

The molecule then drops down to one of the various vibrational levels of the ground electronic state again, emitting a photon in the process. As molecules may drop down into any of several vibrational levels in the ground state, the emitted photons will have different energies and thus frequencies. Therefore, by analysing the different frequencies of light emitted in fluorescent spectroscopy, along with their relative intensities, the structure of the different vibrational levels can be determined.[8] For atomic species, the process is similar; however, since atomic species do not have vibrational energy levels, the emitted photons are often at the same wavelength as the incident radiation. This process of re-emitting the absorbed photon is “resonance fluorescence” and while it is characteristic of atomic fluorescence, is seen in molecular fluorescence as well.

What is fluorescence?

If an atom or molecule first absorbs energy – for instance a photon, this is called excitation. Very shortly (in the order of nanoseconds) after excitation it emits photon of a longer wavelength. We call that fluorescence. (We call it phosphorescence if the emission occurs from same spin state to a longer wavelength).

In a typical fluorescence (emission) measurement, the excitation wavelenth is fixed and the detection wavelength varies, while in a fluorescence excitation measurement the detection wavelength is fixed and the excitation wavelength is varied across a region of interest. In fluorescence spectroscopy, a beam with a wavelength varying between 180-800 nm passes through a solution in a cuvette. We then measure from an angle the light that is emitted by the sample. The concentration of the analyte is directly proportional with the intensity of the emission. There are several parameters influencing the intensity and shape of the spectra. When recording an emission spectrum the intensity is dependent on the:

•   Excitation wavelength
•   Concentration of the analyte solvent
•   Path length of the cuvette
•   Self-absorption of the sample

When can we use spectrofluorometry?

•   Fluorescence analysis is suitable for analytes that can be dissolved in solvents like water, ethanol and hexane.
•   The analytes need to absorb UV or visible light.
•   The analytes need to emit visible or near infrared radiation.
• With fluorescence analysis we can do quantitative measurements of a single analyte in solution (or more than one analytes in solution provided they do not interfere with each other).

## INSTRUMENTATION

Two types of instruments exist: filter fluorometers that use filters to isolate the incident light and fluorescent light and spectrofluorometers that use a diffraction grating monochromators to isolate the incident light and fluorescent light.

Both uses the following scheme: the light from an excitation source passes through a filter or monochromator and strikes the sample. A proportion of the incident light is absorbed by the sample and some of the molecules in the sample fluoresce. The fluorescent light is emitted in all directions. Some of this fluorescent light passes through a second filter or monochromator and reaches a detector, which is usually placed at 90ᵒ to the incident beam to minimize the risk of transmitted or reflected incident light reaching the detector. Various light sources may be used as excitation sources, including lasers, LED and lamp; xenon arcs and mercury-vapor lamps in particular. A xenon arc has a continuous emission spectrum with nearly constant intensity in the range from 300-800 nm and a sufficient irradiance for measurements down to just above 200 nm.

A monochromator transmits light of an adjustable wavelength with an adjustable tolerance. The monochromator is adjusted to select which wavelengths to transmit. As mentioned before, the fluorescence is most often measured at a 90ᵒ angle relative to the excitation light. This geometry is used instead of placing the sensor at the line of the excitation light at a 180ᵒ angle in order to avoid interference of the transmitted excitation light. No monochromator is perfect and it will transmit some stray light, that is. Light with other wavelengths than targeted. An ideal monochromator would only transmit light in the specified range and have a high wavelength independent transmission. When measuring at a 90ᵒ angle, only the light scattered by the sample causes stray light. This results in a better signal to noise ratio and lowers the detection limit by approximately a factor 10000, when compared to the 180ᵒ geometry.

The detector can be single-channelled or multi-channelled. The single-channelled detector can only detect the intensity of one wavelength at a time while the multi-channelled detects intensity of all wavelengths simultaneously.

A general layout of fluorescence spectrophotometer

## Objectives of the Research

Displacement assay of thiochrome from CB7 and addition of hormones (Auxin and Melatonin) followed by determination of the binding constant.

Formation of thiochrome:- Thiamine is visible in the UV range but its relatively common wavelength for absorbance (λmax = 242 nm) and low extiction coefficient do not lend to specific or sensitive analysis. Hence, most commonly, thiamine is converted to thiochrome prior to measurement. This product of oxidation is highly fluorescent with excitation and emission wavelengths of 360 nm and 450 nm respectively.

Oxidation of thiamine to thiochrome

Thiochrome was synthesized by oxidation of anuerin or thiamine (Vitamin B1) with potassium ferricyanide in the presence of sodium hydroxide.

The reaction mixture (thiochrome) contained:-

•   2 mL, 1mM potassium ferricyanide
•   2 mL, 3 mM thiamine
•   1 mL NaOH

Synthesis of Glycouril:-

1)      To water (225 mL), 21.75 mL of glyoxal was added, after this 21.3 g of P4O10 was added slowly over a period of 5 minutes, while constantly stirring.

2)      After this time, 217 g of urea was added and mixture was heated up to 70℃.

3)      After 10 to 15 minutes the solution became cloudy and the product precipitates.

4)      The product was collected by filtration on a Buckner funnel and the solid was washed with cold water and dried.

5)      The product were characterized by 1H NMR spectroscopy.

Synthesis of Glycourils from urea and 1,2- dicarbonyl (glyoxal) compounds.

Reaction Mechanism

Synthesis of Cucurbit[7]uril:-

Chemicals required:- Glycouril, paraformaldehyde, 37% HCl

Detailed procedure:-

1.      Take 10 g (70.35 mmol) glycouril in a 250 mL round bottomed flask and add 14.2 mL HCl to it.

2.      Set the reaction upon a magnetic stirrer taking a magnetic bead inside and stir for 5 minutes.

3.      Add 4.22 g paraformaldehyde and attach condenser. Set the temperature 97℃ and keep it for 18 h, after stabilizing the temperature.

4.      Bring the reaction mixture at room temperature and add 200 mL methanol. Leave it to settle for one day.

5.      Dissolve the dried solid in 250 mL 20% aq. Glycerol (v/v) and heat the mixture at 60-80℃ in open atmosphere.

6.      Filter it and to the filtrate add 200 mL methanol. Leave it undisturbed overnight.

7.      Centrifuge it at 4℃ 10000 rpm for 30 minutes (take the mixture in 50 mL falcon tubes).

8.      Characterize using NMR spectroscopy.

## METHODOLOGY

All fluorescence measurements were performed using Horiba Jobin Yvon Fluorolog fluorimeter, using 1 cm quartz cuvettes. Thiochrome, glycoluril and CB-7 were synthesized in the laboratory as mentioned above. Methanol were purchased from Fluka. Milli-Q water, using Millipore water purification set up from Merck was used.

## Results and Discussions

NMR data of synthesized glycoluril

1H NMR (DMSO-d6) ⸹ 7.16 (4H, NH), 5.24 (2H, CH).

NMR data of synthesized CB7

The NMR data of glycoluril was pure while the NMR data of CB7 had slight impurity of aliphatic compound and the circles indicate the protons corresponding to CB7.

Fluorescence measurements:- The fluorescence spectra of displacement assays is given as below:-

The emission spectra of Thio-CB7- Melatonin

Solvent- 480 uL (Milli Q water)

Excitation wavelength- 360 nm

Melatonin concentration- 5uM

The emission spectra shows the displacement of thiochrome from [CB-7- thiochrome] host-guest complex followed by binding of competitor hormone, Melatonin. Further, increase in intensity confirms the caging of thiochrome inside CB-7. Quenching shows that the thiochrome has been displaced by Melatonin and free thiochrome has been regenerated.

Emission spectra of Thio-CB7-Auxin

Solvent- 480 uL (Milli Q water)

Excitation wavelength- 360 nm

4 mM CB7 in 5uM thiochrome

The titration shows the binding of CB-7 and thiochrome complex while the quenching shows the displacement of thiochrome and binding of Auxin.

Reverse titration of Auxin-CB7-Thiochrome

Solvent- 480 uL (Milli Q water)

Excitation wavelength- 360 nm

Auxin concentration- 5uM

To check whether Auxin has been properly caged inside the CB-7, we had performed the reverse titration. Since the excitation wavelength was set at 360 nm (at this wavelength excitation of thiochrome occurs) and while performing the reverse experiment, initially Auxin showed very less fluorescence. But on further addition of thiochrome and CB7, the fluorescence intensity was matching with the actual experiment confirming the binding of Auxin inside CB-7 cavity.

Host-guest binding titration plots of thiochrome with CB7. It should be noted that the host-guest titrations is fitted to a 1:1 binding model.

## Applications of the Research

• Cucurbiturils, have been demonstrated to show a low, if not negligible, cellular and acute toxicity, possessing potential for drug delivery and stabilization. They stand out, in particular, with respect to their high binding constants with hydrophobic as well as cationic guest molecules. Moreover, they have been shown to effectively shift the pKa values of encapsulated guests.
• An important application for the use of macrocycles in hormone encapsulation is the reversibility of the host-guest complexation, which allows full or partial retention of the biological activity of the encapsulated hormone.
•  Hormones are mostly water-insoluble but on complexation with CB7, the solubility as well as biocompatibility is enhanced.
•  Another application is the optimum release of the hormone from host-guest complex. Slow release of hormones leads to long lasting effect on body.
•  The host-guest complex can be used for treating sleep disorders caused due to low levels of melatonin.
•  The improper growth of plants due to deficiency of hormone Auxin can be reduced by injecting the host-guest complex.

## CONCLUSIONS

As one of the most water-soluble members in the macrocyclic cucurbit[n]uril, CB7 has attracted increasing attention in pharmaceutical and biomedical fields. Due to its appropriate size to accommodate a variety of guest molecules of biomedical interest, CB7 has been extensively investigated as a potential carrier for cationic guests as the molecular encapsulation by CB7 often improved the chemical stability and solubility of the encapsulated guests, controlled their release and modulated their toxicity. Till date, there is no literature report of complexation of Auxin and Melatonin with CB7. Hence, this host-guest complex can be very useful in the area of research as well as biomedical applications.

## REFERENCES

1. Masson, E.; Ling, X.; Joseph, R.; Kyeremeh, L.; Lu, X.; 2012, 2, 1213-1247.

2. Zhang, X.; Xu, X.; Li, S.; Wang, L. H.; Zhang, J.; Wang, R.; (2018) 8:8819. doi :10.1038/s41598-018-27206-6.

3.  Koner, A. L.; Ghosh, I.; Saleh, N.; Nau, W. N.; Can. J. Chem. 89: 139-147 (2011). doi:10.1139/V 10-079.

4. Saleh, N.; Koner, A. L.; Nau, W. N.; Angew. Chem. Int. Ed. 2008, 47, 5398-5401.

5. Principles of Instrumental Analysis F. James Holler, Douglas A. Skoog, Stanley R. Crouch 2006.

6. Saha, S.; Singh, K. M.; Gupta, B. P.; General and comparative Endocrinology 2019, 279, 27-35.

7. J. R. Lakowicz, Introduction to fluorescence, Principles of fluorescence spectroscopy, 3rd Ed. Springer US (2006) pp 3-6.

8. Bernard Valeur, Molecular Fluorescence: Principles and applications.

## ACKNOWLEDGEMENTS

I am using this opportunity to thank IASc-INSA-NASI for giving me the golden opportunity to carry out this project and granting me fellowship for the period as a part of Science Academies’ Summer Research Fellowship Programme 2019.

I am deeply indebted to Dr. Apurba Lal Koner, Assistant Professor, Department of Chemistry, Indian Institute of Science Education and Research, Bhopal, for his guidance, valuable suggestions and constant supervision throughout this work.

It is my privilege to express my profound regards to Prof. Goutam Patra, Department of Chemistry, Guru Ghasidas Central University, Bilaspur (C.G.) for providing my letter of recommendation to Indian Academy of Sciences.

I want to thank my beloved parents for their moral support throughout the research work. Above all, I thank Almighty God for blessing me with health and vitality to complete this project.

I am also grateful for having a chance to meet so many wonderful people who led me through this internship period.

#### Source

• : https://en.wikipedia.org/w/index.php?title=Melatonin&oldid=914796755
• : Principle and application on pharmaceutical analysis. ISRN Spectroscopy. 2013. 1-12.10.1155/2013/230858
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# Meta-analysis and effect synthesis: what, exactly, is the deal?

Suppose we have perfectly executed and perfectly consistent, balanced randomized control trials for a binary treatment applied to populations 1 and 2. Suppose that even the sample sizes are the same in each trial ($latex n$). We obtain consistent treatment effect estimates $latex \hat \tau_1$ and $latex \hat \tau_2$ from each, respectively, with consistent estimates of the asymptotic variances of $latex \hat \tau_1$ and $latex \hat \tau_2$ computed as $latex \hat v_1$ and $latex \hat v_2$, respectively. As far as asymptotic inference goes, suppose we are safe to assume that $latex \sqrt{n}(\hat \tau_1 – \tau) \overset{d}{\rightarrow} N(0, V_1)$ and $latex \sqrt{n}(\hat \tau_2 – \tau) \overset{d}{\rightarrow} N(0, V_2)$, with $latex N\hat v_1 \overset{p}{\rightarrow} V_1$ and $latex N\hat v_2 \overset{p}{\rightarrow} V_2$.* (This is pretty standard notation, where $latex \overset{d}{\rightarrow}$ is convergence in distribution, and $latex \overset{p}{\rightarrow}$ is convergence in probability, under the sample sizes for each experiment growing large.) Even with the same sample sizes in both population, we may have that $latex V_1 > V_2$, because outcomes are simply noisier in population 1. Suppose this is the case.

A standard meta-analytical effect synthesis will compute a synthesized effect by taking a weighted average where the weights are functions, either in part or in their totality, of the inverses of the estimated variances. That is, weights will be close or equal to $latex 1/\hat v_1$ and $latex 1/\hat v_2$. Of course, if $latex \tau_1 = \tau_2 = \tau$, then this inverse variance weighted mean is asymptotic variance-minimizing estimator for $latex \tau$. This is the classic minimum distance estimation result. The canonical econometrics reference for the optimality of inverse variance weighted estimator for general problems is Hansen (1982) [link], although it is covered in any graduate econometrics textbook.

But what if there is no reason to assume $latex \tau_1 = \tau_2 = \tau$? Then, how should we interpret the inverse variance weighted mean, which for finite samples would tend to give more weight to $latex \hat \tau_2$? Perhaps one could interpret it in Bayesian terms. From a frequentist perspective though, which would try to relate this to stable population parameters, it seems to be interpretable only as “a good estimate of what you get when you compute the inverse variance weighted mean from the results of these two experiments,” which of course gets us nowhere.

Now, I know that meta-analysis textbooks talk about how, when it doesn’t make sense to assume assume $latex \tau_1 = \tau_2$, one should seek to explain the heterogeneity rather than produce synthesized effects. But the standard approaches for doing so rely on assumptions of conditional exchangeability— that is, replacing $latex \tau_1 = \tau_2$ with $latex \tau_1(x) = \tau_2(x)$, where these are effects for subpopulations defined by a covariate profile $latex x$. Then, we effectively apply the same minimum distance estimation logic, using inverse variance weighting to compute the $latex \tau_2(x)$, most typically with an inverse variance weighted linear regression on the components of $latex x$. The modeling assumptions are barely any weaker than what one assumes to produce the synthesized estimate. So does this really make any sense either?

It seems pretty clear to me that the meta-analysis literature is in need of a “credibility revolution” along the same lines as we’ve seen in the broader causal inference literature. That means (i) thinking harder about the estimands that are the focus of the analysis, (ii) entertaining an assumption of rampant effect heterogeneity, and (iii) understanding the properties and robustness of estimators under (likely) misspecification of the relationship between variables that characterize the populations we study (the $latex X_j$s for populations indexed by $latex j$) and the estimates we obtain from them (the $latex \hat \tau_j$’s).

*Edited based on Winston’s corrections!

## 3 thoughts on “Meta-analysis and effect synthesis: what, exactly, is the deal?”

1. Winston

Cyrus, I’m guessing you know some or all of these references, but in case any of them help give moral support:

• Freedman and Berk, “Statistical assumptions as empirical commitments” (“Just say no” to meta-analysis.)

• Freedman, “Oasis or mirage?” (Annotated references point to several critiques of meta-analysis.)

• Briggs, “Meta-analysis: A case study” (“Researcher subjectivity is no less problematic in the context of a meta-analysis than in a narrative review.”)

• Berk, “Statistical inference and meta-analysis” (with discussion), J Exp Criminol (2007) 3:247-297. (Comments by Lipsey and Shadish are thoughtful and witty, but I’m more persuaded by Berk’s rejoinder: “My take is that by and large, the meta-analyses used to inform social science and public policy do not deliver on their claims. On the matter of whether they are good enough, my view is that they typically are not even close. I would be delighted to be proved wrong.”)

Minor point: on the asymptotics, I think you meant to write something like suppose we’re safe to assume sqrt(n) (tau1hat – tau) converges in distribution to N(0, V1) with n times v1hat converging in probability to V1, etc.

2. Cyrus Post author

Great references, Winston.

And thanks for catching the rookie mistake with the asymptotics! I’ve edited those in the post.

3. Winston

Just remembered this NYT article from 5 years ago:

“Dr. Bruce P. Barrett, an associate professor of family medicine at the University of Wisconsin who was not involved with the review, said he was not convinced of the value of combining the studies in a single analysis.

” ‘If you’re testing the same intervention on the same population using the same outcome measures, then meta-analysis is a very good technique,’ Dr. Barrett said. ‘But here every one of those things fails.’ “

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# The abundance and physical properties of O VII and O VIII X-ray absorption systems in the EAGLE simulations

Wijers, NA, Schaye, J, Oppenheimer, BD, Crain, RA and Nicastro, F (2019) The abundance and physical properties of O VII and O VIII X-ray absorption systems in the EAGLE simulations. Monthly Notices of the Royal Astronomical Society, 488 (2). p. 2947. ISSN 0035-8711

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We use the EAGLE cosmological, hydrodynamical simulations to predict the column density and equivalent width distributions of intergalactic O VII ($E=574$ eV) and O VIII ($E=654$ eV) absorbers at low redshift. These two ions are predicted to account for 40% of the gas-phase oxygen, which implies that they are key tracers of cosmic metals. We find that their column density distributions evolve little at observable column densities from redshift 1 to 0, and that they are sensitive to AGN feedback, which strongly reduces the number of strong (column density $N \gtrsim 10^{16} \, \mathrm{cm}^{-2})$ absorbers. The distributions have a break at $N \sim 10^{16} \, \mathrm{cm}^{-2}$, corresponding to overdensities of $\sim 10^{2}$, likely caused by the transition from sheet/filament to halo gas. Absorption systems with $N \gtrsim 10^{16} \mathrm{cm}^{-2}$ are dominated by collisionally ionized O VII and O VIII, while the ionization state of oxygen at lower column densities is also influenced by photoionization. At these high column densities, O VII and O VIII arising in the same structures probe systematically different gas temperatures, meaning their line ratio does not translate into a simple estimate of temperature. While O VII and O VIII column densities and covering fractions correlate poorly with the H I column density at $N_{\mathrm{H \, I}} \gtrsim 10^{15} \, \mathrm{cm}^{-2}$, O VII and O VIII column densities are higher in this regime than at the more common, lower H I column densities. The column densities of O VI and especially Ne VIII, which have strong absorption lines in the UV, are good predictors of the strengths of O VII and O VIII absorption and can hence aid in the detection of the X-ray lines.


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# Quien quiere ser mi novia

###### Question:

Quien quiere ser mi novia

### Find the measure of side b.

Find the measure of side b. $Find the measure of side b.$...

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### What was the Christmas Truce of 1914 (no wikipedia pls )

What was the Christmas Truce of 1914 (no wikipedia pls )...

### If 255 g of water has 10.0 g of nacl dissolved into initially, how much nacl must be added in order

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### Describe the following sequence using an algebraic expression as a rule 0; 2,4; 6

Describe the following sequence using an algebraic expression as a rule 0; 2,4; 6...

### For what frequencies does their sound at the speakers produce constructive interference?

For what frequencies does their sound at the speakers produce constructive interference?...

### What is the probability of throwing several dice with sum equal to 6 (six)? show the

What is the probability of throwing several dice with sum equal to 6 (six)? show the ways of possibilities for sum 6 (as the numerator) and the ways of throwing n dices for n = 1, 2, 3, 4 or 5 as denominator for all the questions to earn full credits. (a)throw one die, (b) throw two dice, (c) throw...

### I have an oxidation number of -3 and I have 5 energy levels. What element am I?A. YttriumB. PhosphorusC.

I have an oxidation number of -3 and I have 5 energy levels. What element am I? A. Yttrium B. Phosphorus C. Antimony D. Bismuth...

### Polygenic traits, traits determined by more than one gene, often have phenotypes that are distributed

Polygenic traits, traits determined by more than one gene, often have phenotypes that are distributed on a bell curve. occurs when one end of the bell curve is better adapted to the environment than the other. Natural selection disrupts the because one allele of a gene is preferred over another, ...

### Can someone check my essay to see if it is good? should americans have the right to freedom of speech?

Can someone check my essay to see if it is good? should americans have the right to freedom of speech? the right to free speech is one of the most cherished rights any civilian could have in the united states. but it was not until 1791 when freedom of speech was established in the first amendmen...
I need help on the 2 questions on the last image $I need help on the 2 questions on the last image$$I need help on the 2 questions on the last image$$I need help on the 2 questions on the last image$...


text: Search for low mass vector resonances decaying into quark-antiquark pairs in proton-proton collisions at s = 13 \$\$ \sqrts=13 \$\$ TeV


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3.13

## Precalculus

Skip to 0 minutes and 11 secondsHello. Let us consider the first exercise of the "Polynomial division in practice" step. We have to divide this polynomial by this one. Then we have to write the first one-- x to the fourth minus x to the third plus x squared minus 3 times x minus 1. Then we consider this line and this other line. And here, now we write the polynomial x squared plus 1, for which we want to divide this polynomial. OK, which is the idea now? I have to write down here something that multiplied by x squared gives me the term of maximum degree in this expression, which is this one-- x to the fourth.

Skip to 1 minute and 19 secondsOK, then clearly, if I write here x squared, we have that the x squared times x squared is exactly equal x to the fourth. OK, and now what do we do? Then we make this multiplication and this multiplication, and we write under this polynomial what we get. We get x squared times x squared, which is x to the fourth plus 1 times x squared, which is plus x squared. You see, I have written the new terms under the previous terms of the same degree. And now I have to do the subtraction between this polynomial and this polynomial. And what do we get? x to the fourth minus x to the fourth is 0.

Skip to 2 minutes and 20 secondsMinus x to the 3 minus 0 is minus x to the three. x squared minus x squared is 0. And then we have minus 3x minus 1. And now I repeat exactly the same algorithm.

Skip to 2 minutes and 42 secondsNow I am asking myself: for what I have to multiply this term to get the term of maximum degree now in this new line. You see? I have to multiply x squared times minus x to get minus x cubed.

Skip to 3 minutes and 4 secondsOK, let us go on. x squared times minus x is minus x cubed. And then I have plus 1 times minus x, which is minus x. And again, I consider the subtraction of these two polynomials, and I have 0 here. And here, I have minus 3x and minus minus x, which is minus 2x minus 1. And now you see I have reached a polynomial which is of degree less than 2-- less than the degree of the polynomial for which we are making our division.

Skip to 4 minutes and 0 secondsTherefore, we can stop, and we can conclude that x to the fourth minus x to the 3 plus x squared minus 3 times x minus 1 is equal to x squared plus 1 times x squared minus x plus the remainder, which is minus 2x minus 1.

Skip to 4 minutes and 39 secondsHello. Let us consider the second exercise of the "Polynomial division in practice" step. It's another division between two polynomials. Then let us apply the same algorithm as before-- as exercise 1. Then we write x cubed minus 8 on the side. Then we consider this line, another line. And here, I write x minus 2. OK, I have now to find something that multiplied by x gives me x cubed. This is x squared. And now I make the multiplication of this polynomial by this guy, and I get x times x squared, which is equal to x cubed and minus 2 times x squared, which is minus 2 x squared. And now I take the subtraction of these two polynomials.

Skip to 5 minutes and 49 secondsThe subtraction between two polynomials is done considering the subtraction of terms with the same degree. And then I have x cubed minus x cubed, which is 0. Then here, there is no terms of degree 2 minus minus 2 x squared, which is 2 x squared. And then I have minus 8. Here, there are no terms of degree 0. And then I get just minus 8. OK, and now I repeat the same argument. For what I have to multiply x to get 2 x squared? Of course, I have to multiply x by 2x.

Skip to 6 minutes and 41 secondsAnd in such a way, I get x times 2x, which is 2 x squared, and minus 2 times 2x, which is minus 4x. And I again consider the subtraction of these two polynomials, and I immediately get 4x minus 8.

Skip to 7 minutes and 7 secondsAttention: the degree of this polynomial is not strictly less than the degree of this polynomial, the polynomial for which I am making a division. Therefore, I cannot stop here. I have to continue. And then now, I ask myself, for what I have to multiply x to get 4x? Of course, by 4-- and I get x times 4, which is 4x minus 2 times 4, which is minus 8. And when I consider here the subtraction of these two polynomials, immediately I get 0. What means? This means that the remainder of this division is equal to 0. Then we have that x cubed minus 8 is equal to x minus 2 times x squared plus 2x plus 4 plus 0.

Skip to 8 minutes and 17 secondsTherefore, I can conclude that this equality is true.

# Polynomial division in practice

The following exercise is solved in this step.

We invite you to try to solve it before watching the video.

In any case, you will find below a PDF file with the solution.

### Exercise 1.

Divide the polynomial $$x^4-x^3+x^2-3x-1$$ by $$x^2+1$$.

### Exercise 2.

Divide the polynomial $$(x^3-8)$$ by $$(x-2)$$.

### Exercise 3. [Solved only in the PDF file]

Make the following divisions between polynomials:

i) $$(2x^3-3x^2+3x+2) : (2x-1)$$;

ii) $$(x^4+2x^3-2x^2-5):(x+x^2-4)$$.


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# Strong gravity

## Recommended Posts

We learned that gravity is the weakest force in nature.

My thinking is that is might be not so weak. Maybe the apparent weakness of gravity is a consequence of the reference frame we use to mesure that force.

I know that this idea look strange, but try to follow my reasonning.

Usually we fix a reference frame to something material: the table in the laboratory, the earth, the sun, a space ship the center of the Milkyway...

and we say this is the zero point from which we do our mesurement.

But matter is only a small fraction of our universe, most of it is energy and dark energy, so is it a good idea to fix our reference frame on the material exception ?

The universe is expanding in general and contracting on smaller region where there is enought matter, so can't it be that the basic, natural reference frame be an expanding reference frame ??

Relativity enable us to switch from one reference frame to the other and the only constant is c. Wouldn't it be more natural to use c has the 0 speed ?

A photon would be stationary in that reference frame. All material objects would have a speed of -1 c.

Also we would not need the BigBang to explain the expansion of the universe: the universe is expanding because it is its natural state. Gravity is a force who goes against that natural expansion. What we mesure has gravity is only second order fluctuation of what I called here the "strong gravity"

I would like to know if that make some sense to you ?

Thanks

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So how would you like to see gravity measured?

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Wow, thats an incredible line of reasoning.

I've wondered the same about gravity being a "weak force." I've thought its a matter of scale.

Your line of reasoning is pretty amazing. I've emailed it to myself!

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I would like to know if that make some sense to you ?

Thanks

No.

Bettina

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I think you're reasoning this way because you gravity is one of the only real natural forces you can experiance. Let's imagine that you were so small, that you able to visit an atom and experiance the strong forces that hold atoms together. This force would be unlike anything you had ever experiance, and you would see why gravity is considered a weak force.

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I see what you mean...sort of.

But I still disagree.

To say that the universe is made up primarily of enegry isn't exactly true but in any case, it doesn't matter. Enegry doesn't "exist" in the terms of distance; I don't walk 5,000 J to school every morning. To say that gravity isn't a weak force because we aren't measuring it correctly is a nice idea, but doesn't exactly stand to reason. Gravity is "weak" because how it interacts with atoms, something that really doesn'y have to do with the difference between matter/enegry/dark enegry. It's "weak" because it governs beta decay and neutrino interactions with nuclei while "strong" forces of nuclear enegry control the binding of quarks to create baryons and the like. The nuclear force is stronger than the weak, so it is named as such. So, your idea is creative, but isn't exactly asking/answering the right thing when it comes to weak vs. strong forces.

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I see what you mean...sort of.

But I still disagree.

Wait... are you talking about what I said, or the OP?

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The OP. I agree with you, I just gave my answer more roundaboutly.

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So how would you like to see gravity measured?

I don't know yet I didn't ask myself that question. Let me try to continue my reasonning.

First we have the basic (natural) state of the universe is expansion. A massless particle like photon does not need any energy to move at the speed of light. It is just carried away with the progession (expansion) of space. The progession of space is 3 dimensional and something to exist must diverge from that progression. The photon diverge from that progression by having 1 negative motion that cancel the progression in one dimension and leaving the other dimension of the progression unaffected. Material things like electron quark etc... Cancel the 3D of the progression. It might have something todo with $E=mc^2$

s space

t time

progression=$s^3/t^3$

mass=$t^3/s^3$

E=$t/s$

$E=mc^2 => t/s=t^3/s^3 s^2/t^2$

Maybe I should used inverse motion instead of negative motion...

So energy is a 1D inverse motion and mass is a 3D inverse motion.

OK for now I think I told enought. I don't want to bother you to much with these crazy idea but I am open to continue if there is some interest in what I say.

Thanks

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Gravity is the weakest force between two particles but it is unique in that it affects all particles with mass, simultaneously. The other forces, like the strong nuclear force reaches its limit at 200-250 protons and neutrons. The EM force is also stronger but is often satified with just two particles. The overall summation of this weak gravity force, makes it stronger than the overall summation of all the rest. This allows us to have blackholes where the rest of the forces become overwelmed by gravity.

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it affects all particles with mass, simultaneously.

Do you suppose that gravity act instantly ?

The overall summation of this weak gravity force, makes it stronger than the overall summation of all the rest. This allows us to have blackholes where the rest of the forces become overwelmed by gravity.

Good point ! The weakes is finaly the strongest !

No.

Bettina

That make no sense to you ? Where do you lose me ?

experiance the strong forces that hold atoms together. This force would be unlike anything you had ever experiance, and you would see why gravity is considered a weak force.

I am temped to answer you that the strong force is nothing else than 'strong' gravity. I will define strong gravity as the negative of the universal expansion.

The univerasl expansion bring every thing apart. Gravity goes again that universal expansion. Gravity brings every thing togeter. Mathematically speaking: universal expansion is a positive scalar and gravity a negative scalar.

Enegry doesn't "exist" in the terms of distance; I don't walk 5,000 J to school every morning.
I don't understand what you are refering to ???
It's "weak" because it governs beta decay and neutrino interactions
In didn't knew that gravity had something to do with that ! I thaught that it was the weak nuclear force governing that scale ...
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Wow' date=' thats an incredible line of reasoning.

[/quote']

Pity we don't have 'sarcasm' tags...

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Could gravity be weak because it's force is split between 4 dimensions (or however many there really are in the Universe) where as all the other forces aren't?

Therefore we can only recognise 1/4 (or an 1/11th or a 1/14th) of the true strength of gravity?

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Pity we don't have 'sarcasm' tags...

I don't get your point. Maybe thats the same reason I'm so easily impressed?

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Could gravity be weak because it's force is split between 4 dimensions (or however many there really are in the Universe) where as all the other forces aren't?

Therefore we can only recognise 1/4 (or an 1/11th or a 1/14th) of the true strength of gravity?

That is actually a very good comment. This is currently one of the suggestions, that gravity is diluted by leaking into the extra dimensions. It works out that it is not a factor of 1/d (where d is the number of dimensions) but is highly dependent on how tightly the extra dimensions are curled up. Potentially one can put limits on this at the LHC.

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edited cause i missed what i was saying was already posted by severian.

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If I understand what you are saying, matter in the universe "repels" itself by one force, similar to like-charged elements, and we measure gravity as the slim net degree by which it is stronger?

If that is the case, then this lesser expansive force must also have the same x/d^2 factor that gravity has to maintain a constant net difference, or one of the forces would become more dominate at some distance.

That may be totally off, especially if you differeniate that some areas are expanding while others are contracting due to enough matter within a region which implies these two forces are not perfectly syched and balanced.

All the reference frame stuff is over my head.

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If I understand what you are saying, matter in the universe "repels" itself by one force, similar to like-charged elements, and we measure gravity as the slim net degree by which it is stronger?

No you don't understand what I am saying. No, matter doesn't repel itself.

What I am saying is that space naturally expand. Space doesn't need any original force or energy to expand. Space expand and doesn't stop to expand unless a force going in the opposite direction is applied. I can call it the compressing force by opposition with the universal expansion. I prefer to call it strong gravity.

The space expansion happen in 3 dimensions. Any direction you look, space expand (outside our local group of galaxies ). Gravity is also 3 dimensionnal but in the opposite direction. If there is enought of that force going against the expasion in the 3D, you have mass. Space expansion is stopped, but the time expansion doesn't stop. The units of space instead of expanding, are reused again and again in multiples 3D rotations combinations.

If that is the case, then this lesser expansive force must also have the same x/d^2 factor that gravity has to maintain a constant net difference, or one of the forces would become more dominate at some distance.

Yes the inverse square law apply. Yes at some distance the expansion dominate. That distance is called the gravitationnal limit.

For the inverse square follow that analogy:

Figure the space expansion as a foam of soap bubble with air continuously injected. Figure mass as a vacuum cleaner . The effect of the vacuum cleaner is to destroy the bubble around the hole and the the further away from the hole the smaller the effect.

Anyway thanks for your interest but I don't feel that these thaught interest many of you.

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No you don't understand what I am saying. No' date=' matter doesn't repel itself.

What I am saying is that space naturally expand. Space doesn't need any original force or energy to expand. Space expand and doesn't stop to expand unless a force going in the opposite direction is applied. I can call it the compressing force by opposition with the universal expansion. I prefer to call it strong gravity.

The space expansion happen in 3 dimensions. Any direction you look, space expand (outside our local group of galaxies ). Gravity is also 3 dimensionnal but in the opposite direction. If there is enought of that force going against the expasion in the 3D, you have mass. Space expansion is stopped, but the time expansion doesn't stop. The units of space instead of expanding, are reused again and again in multiples 3D rotations combinations.

[/quote']

I think I understand what you are saying better. Matter moves apart as if repulsed, but as a side effect of the space it exists in expanding naturally, and the attractive capacity of gravity causes mass to overcome the expansion effect with the net effect of appearing weak.

Yes the inverse square law apply. Yes at some distance the expansion dominate. That distance is called the gravitationnal limit.

For the inverse square follow that analogy:

Figure the space expansion as a foam of soap bubble with air continuously injected. Figure mass as a vacuum cleaner . The effect of the vacuum cleaner is to destroy the bubble around the hole and the the further away from the hole the smaller the effect.

Anyway thanks for your interest but I don't feel that these thaught interest many of you.

I am not sure if this can work mathatically.

Gravity appears to have a consistant strength at any distance according to the inverse square. If the expansion factor would have to be exactly inverse square as well, and neither force would dominate, or it would have to have something other than an inverse square strength of effect so that at a great distance it could be more powerful than gravity.

If the latter is the case, I don't think gravity could follow the inverse square law as it is observed to. Unless there is a mathmatical formula that matches inverse squared perfectly for a large portion of the function and then suddenly veers off at a specific value (to account for expansion effect deluting then dominating gravity) or gravity cannot be 1/d^2 based. And if the latter is true in that case, you would still need a formula in which the sum of gravity attraction and spatial expansion is a net 1/d^2 perfectly then veers off to allow expansion to dominate.

I don't know complex math, or even what many would consider fairly simple math, but I am suspect if a single formula can appear to be 1/d^2 exactly for a large portion of the function and then veer into the negative (ie where expansion is greater than attraction) to successfully describe the effect you are contemplating.

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gravity is not weak,its strong enough to let the atoms combine together,if u think gravity is weak why cant u break iron bar just by your hand

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gravity is not weak,its strong enough to let the atoms combine together,if u think gravity is weak why cant u break iron bar just by your hand

Gravity is considered weak when compared to the other forces, and understanding why it is so much weaker than the others is considered a dilema of sorts in physics.

The gravitational attraction between protons is approximately a factor of 10^36 weaker than the electromagnetic repulsion.
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gravity is not weak,its strong enough to let the atoms combine together,if u think gravity is weak why cant u break iron bar just by your hand

The iron bar is held together by electromagnetism - not gravity. The very fact that gravity can't pull the iron bar apart (try holding just one end of the bar) shows that it is much weaker than electromagnetism.

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We learned that gravity is the weakest force in nature.

My thinking is that is might be not so weak. Maybe the apparent weakness of gravity is a consequence of the reference frame we use to mesure that force.

I know that this idea look strange' date=' but try to follow my reasonning.

Usually we fix a reference frame to something material: the table in the laboratory, the earth, the sun, a space ship the center of the Milkyway...

and we say this is the zero point from which we do our mesurement.

But matter is only a small fraction of our universe, most of it is energy and dark energy, so is it a good idea to fix our reference frame on the material exception ?

The universe is expanding in general and contracting on smaller region where there is enought matter, so can't it be that the basic, natural reference frame be an expanding reference frame ??

Relativity enable us to switch from one reference frame to the other and the only constant is c. Wouldn't it be more natural to use c has the 0 speed ?

A photon would be stationary in that reference frame. All material objects would have a speed of -1 c.

Also we would not need the BigBang to explain the expansion of the universe: the universe is expanding because it is its natural state. Gravity is a force who goes against that natural expansion. What we mesure has gravity is only second order fluctuation of what I called here the "strong gravity"

I would like to know if that make some sense to you ?

Thanks[/quote']

What if we try a simple explanation? (see attachement)

Kris

Gravity.doc

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# God Game

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I wonder if a true believer can pass this test without harm.

Are you saying theistic belief carries inherent contradictions? o.O

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Are you saying theistic belief carries inherent contradictions? o.O

Where is a devout believer when you need one?

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Are you saying theistic belief carries inherent contradictions? o.O

Not being a believer myself, the test gave me the impression it was its hidden agenda. As an atheist, each question that begins with " if God ...) was automatically answered by "false" without much thinking. That makes 70% of the test really easy. That was the reason of my comment.

----------------------------------------------------------------------

P.S. Although "He" acted following the rules, I really don't like the abrupt way some other forum's member was rejected from the discussion. I hope he will come back again after succeeding his 50 posts corvée.

Edited by michel123456
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I'm a staunch atheist so I couldn't get through the third question

"Any being which it is right to call God must be free to do anything."

There is no being which it is right to call God and therefore it is impossible to rationally assign properties to it.

I couldn't answer yes or no to that any more than I could answer the question "Do unicorns have gall bladders?"

How did you decide what properties God would have?

Presuming that if a unicorn exists it is defined as a white horse with a horn on its head.

Q If the Unicorn exists does it have a gall bladder

A Yes (I think horses will have gall bladders)

Q If the Unicorn exists does it eat rocks

A No - we have defined it as very horselike

To deny the existence of a Unicorn one must have a fairly clear conception of what a Unicorn is defined as (ie it cannot just be defined as a mammal with a spiral grooved horn on its forehead - qv narwhal). Doesn't the same apply to god?

Congratulations!

You have been awarded the TPM medal of honour! This is our highest award for outstanding service on the intellectual battleground.

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Presuming that if a unicorn exists it is defined as a white horse with a horn on its head.

Q If the Unicorn exists does it have a gall bladder

A Yes (I think horses will have gall bladders)

Q If the Unicorn exists does it eat rocks

A No - we have defined it as very horselike

To deny the existence of a Unicorn one must have a fairly clear conception of what a Unicorn is defined as (ie it cannot just be defined as a mammal with a spiral grooved horn on its forehead - qv narwhal). Doesn't the same apply to god?

See, that's just it. I don't think of unicorns as being necessarily white, but I do think of them as having supernatural properties, as they are generally depicted as more than simply a mundane horse with a horn on its head.

So yes, I am confident that there does not exist a being that I would call a unicorn, although I have only the vaguest definition of what that would actually be. Certainly not specific enough to say whether it has a gall bladder. And yes, there are some definitions of "unicorn" that could be said to exist (narwhale, rhinoceros), but I wouldn't call those things unicorns.

Similarly, I'm fairly confident that there does not exist something that I would call "god," even though there are countless hypothetical beings with various properties (more varied than unicorns) that might reasonably be called by that name. And there are things which do exist (the laws of physics, the universe itself) which some might call "god," but I would not.

So even the question "does god exist" can only be given a very casual answer without an explanation of what is meant by the word.

EDIT: I'm looking at the Wikipedia article on unicorns, and it's very interesting. Apparently Marco Polo described finding "unicorns:"

scarcely smaller than elephants. They have the hair of a buffalo and feet like an elephant's. They have a single large black horn in the middle of the forehead... They have a head like a wild boar's… They spend their time by preference wallowing in mud and slime. They are very ugly brutes to look at. They are not at all such as we describe them when we relate that they let themselves be captured by virgins, but clean contrary to our notions.

Clearly he's describing a rhinoceros. Yet apparently it didn't occur to him that he was describing a different animal - he thought it was the mythological unicorn, but that it had entirely different properties from popular conception!

Clearly, it's a problem of defining the essential properties of a thing. Who's to say that a rhinoceros is not, in fact, a unicorn?

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I wonder if a true believer can pass this test without harm.

It turns out that it's rather easy to pass this as a theist.

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A couple of points,

Deer have no gall bladders and I rather suspect horses don't either; not many people know that and that's why I chose that particular property to ascribe (or not) to a unicorn.

Secondly, a Diabolist might chose to ascribe an entirely different set of properties to "The Supreme Ruler" compared to, for example, a Christian.

What properties your God has are entirely up to you.

If I were to manipulate the genes of a horse and a rhino to get something that was basically a horse, but with a horn, I don't think it would count as a unicorn because, one of the defining properties of unicorns is that they don't exist.

For that definition this "To deny the existence of a Unicorn one must have a fairly clear conception of what a Unicorn is defined as " simply doesn't hold true. I can deny their existence on the basis that they are mythical (WIKI says so, therefore it must be right); anything that you or I say about the unicorn is impossible to disprove.

Edited by John Cuthber
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I got a perfect score. How'd you do?

Show off.

I closed the window out before I had a chance to copy and paste the one hit I took. I am quite embarrassed that I stepped into such an erroneous and illogical misstep! I think I must have read the question wrong? *blushes*

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A couple of points,

Deer have no gall bladders and I rather suspect horses don't either; not many people know that and that's why I chose that particular property to ascribe (or not) to a unicorn.

I had a feeling it might have been - should have checked. Have checked now with the fount of all knowledge: "Equids do not have a gall bladder, so bile flows constantly, an adaptation to a slow but steady supply of food, and another reason for providing fodder to horses in several small feedings."

I think we could go around the block many times on the logical/philosphical bit - and I have no intention of starting

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I I took a hit for the question on evolution too. I think the way it's worded is misdirectional in the way that it asks you whether you agree that evolution THEORY is true or false. I said false, as while I belive Evolution theory over some all magical glowing rainbow pixie it's still a theory ( How things happen, not that they do or not) If it was true wouldnt Evolution theory be a law?

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If it was true wouldnt Evolution theory be a law?

No.

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So in the scientific world what officially makes something a law?

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Took one direct hit... but I disagree with it.

Anyway, it's a funny exercise

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I bit the bullet on one. It was the one about square circles. I said an omnipotent God could create square circles, because it was only an arbitrary name we placed on certain geometric shapes. Even a human could change sign convention.

Hm. Not too bad for a YEC, crazy republican.

So in the scientific world what officially makes something a law?

No theory ever becomes a law. It doesn't work like that. Laws are not higher truths.

Laws are generalizations about what has happened. They pertain to observational data. An ability to predict in other words. Gravity is a good example. There is obviously an attraction between all things with mass. And from it, we can predict certain behaviors. That doesn't mean we understand everything about gravity (we have a pretty good handle, but there are still varying theories on gravity).

In the same sense that nature is not obliged to agree with our theories, it is not obliged to obey our laws.

Edited by A Tripolation
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Hm. Not too bad for a YEC, crazy republican.

Wasn't it a gay communazi YEC crazy republican?

No theory ever becomes a law. It doesn't work like that. Laws are not higher truths.

Right. 'Law' is typically reserved for specific mathematical statements. As you said, gravity is a Law....sort of: $F=G\frac{mM}{r^2}$ is a Law; the fact of gravity is not a law. Laws are usually a subset of a theory. Indeed, theories do not become laws; theory is as good as it gets in science.

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So in the scientific world what officially makes something a law?

When it has the word "law" in it. There's no difference between a "law" and a "theory" in science, and we've replaced the "universal law of gravitation" with the "theory of general relativity". I think the only requirement for something to be a "law" would be that it has to be a mathematical formula, and even more importantly be from before we stopped calling things laws.

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Edtharan, there may be mathematical proof that evolution is possible, but that doesn't translate to mathematical proof that it actually happened. (which would be impossible to have mathematical proof for anyways).

I got caught by that question too, since I assumed the question was meaningful, ie that by "certain, irrevocable proof" it meant something that was in theory possible for the most certain beliefs we have about the natural world.

The question on the existance of evolution was not about biological evolution. I will agree that there is no "certain, irrevocable proof" of biological evolution and that ther eis not mathematical proof of biological evolution, but as the question on evolution was not specific to biological evolution, then the test is false.

There is proof of evolution as a process (specifically as an algorithm). This is evolution, even if it is non biological evolution.

If the test specified biological evolution, then I would agree with you and I would ahve had to admit an incosistancy (but I would have answered differently on the evolution question if that was the case and then it would not have been inconsistant).

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• 6 months later...

I took the following hit:

"Earlier you claimed that it is not justifiable to base one's beliefs about the external world on a firm, inner-conviction, paying no regard to the external evidence, or lack of it, for the truth or falsity of this conviction. But now you say that the rapist Peter Sutcliffe was justified in basing his beliefs about God's will solely on precisely such a conviction. That's a bull's-eye for the intellectual sniper!"

The logic is wrong. The second questions asked about belief in God. Belief that God exists, and belief that you are following God's will are two different things. You are not doing what it says in the second sentence.

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You took zero direct hits and you bit 3 bullets. The average player of this activity to date takes 1.37 hits and bites 1.09 bullets. 530705 people have so far undertaken this activity.

Really, God is a "she"? When the gender is unknown, we use he.

Edited by Brainteaserfan
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@Brainteaserfan: Actually the bible calls God a he throughout it's entirety, and Adam - the first human - was a male who was made in God's image. Eve, the first woman, was made from Adam's rib and so she is not made in God's image.

If you believe the Judeo-Christian book of folklore, then God is male.

Edited by Incendia
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@Brainteaserfan: Actually the bible calls God a he throughout it's entirety, and Adam - the first human - was a male who was made in God's image. Eve, the first woman, was made from Adam's rib and so she is not made in God's image.

If you believe the Judeo-Christian book of folklore, then God is male.

I'm talking about god more generally.

However, "made in God's image" could have a few meanings IMO. The Bible calling Him a he does not clarify, because if he was "no" gender, then we would still use he.

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text:
# Linear representation theory of double cover of symmetric group

This article gives specific information, namely, linear representation theory, about a family of groups, namely: double cover of symmetric group.
View linear representation theory of group families | View other specific information about double cover of symmetric group

## Particular cases

Note that for every $n \ge 4$, there are two different double covers $2 \cdot S_n^-$ and $2 \cdot S_n^+$. However, both of them have the same degrees of irreducible representations, though the actual set of irreducible representations depends on the group.

$n$ $2(n!)$ (order of $2 \cdot S_n^-$ and $2 \cdot S_n^+$ $2 \cdot S_n^-$ $2 \cdot S_n^+$ number of irreducible representations (= number of conjugacy classes) degrees of irreducible representations number of irreducible representations of $S_n$ (correspond to irreducible representations of either double cover that have the center in the kernel) degrees of these irreducible representations number of irreducible representations of the double cover that do not have the center in their kernel degrees of these irreducible representations linear representation theory information on $2 \cdot S_n^-$ linear representation theory information on $2 \cdot S_n^+$
4 48 binary octahedral group general linear group:GL(2,3) 8 1,1,2,2,2,3,3,4 5 1,1,2,3,3 3 2,2,4 link link
5 240 double cover of symmetric group:S5 of minus type double cover of symmetric group:S5 of plus type 12 1,1,4,4,4,4,4,5,5,6,6,6 7 1,1,4,4,5,5,6 5 4,4,4,6,6 link link


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Here's the question you clicked on:

## zpupster Group Title using this \begin{array}{l|l|l} i want no outside borders like this: 10 months ago 10 months ago

• This Question is Closed
1. UnkleRhaukus

 $\begin{array}{|l|l|l|} \hline 1&2&3\\ \hline a&b&c\\ \hline \end{array}$  $\begin{array}{|l|l|l|} \hline 1&2&3\\ \hline a&b&c\\ \hline \end{array}$  $\begin{array}{lll} 4&5&6\\ d&e&f\\ \end{array}$  $\begin{array}{lll} 4&5&6\\ d&e&f\\ \end{array}$


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# Would this bit-fiddling question be on topic?

I have a non-challenge, bitwise-gymnastics question that I am looking for a home for. Would this be on topic here?

Per some requirements, I am trying to pack three data points into 16-bits for the fourth position of an Assembly's Version (in .NET, the fourth position of a version number cannot exceed UInt16.MaxValue-1 ). In our build system we are trying to codify three data points into this value every time a CI build is initiated:

• Year
• Day of Year
• Build Revision (resets daily, starts at 1)

The criteria are:

• Values are unique
• Values are reversible back to their original components
• For Year=M, Day=N+1 produces a final result greater than Day=N
• And by extension, all values for Year=M+1 are greater than all Year=M
• or rather, Year=M+1, Day=1 is greater than Year=M, Day=366

(The last two points basically saying that the value between any two consecutive days is strictly increasing)

The best I've come up with is to store that as:

• 2 bits for the number of years since 2019 (ie 2019=0)
• 9 bits for the day of the year
• 5 bits for the revision number

So basically: (Years << 14) | (Day << 5) | Revision

My solution works, but for various reasons I'm trying to find a way to extend the range of supportable revision numbers. I feel like I can somehow borrow some of the leftovers from the day-of-year (since I have 512-366=146 unused values) but I can't seem to find a way to make that work such that it meets my criteria and that I'd be able to reverse it.

Question:

Is it possible through some bitwise tricks to extend the supported range for the revision (and if so, how)? Or have I reached the limits of a 16-bit number?

Meta-Question:

Is this on-topic? After reading the site rules, I'm guessing no, unless it can fall into the non-challenge category. I'm not sure if this would even be on topic over on SO, but even if it were I feel like I'd get much better solutions here (assuming there even are any). Is this "puzzly enough" or should I try my luck elsewhere?

• If you allow arbitrarily complicated and long-running compression and decompression algorithms, it's surely possible to pack optimally as long as there's at most 2^16 valid options, even with the monotonicity restriction. So, for this to be an interesting challenge and maybe reflect the goals of bit packing, I think you'd need to either make the challenge code golf to reward short solutions, or impose some sort of complexity or run-time bound or scoring function. I think this has potential as a challenge. You'd definitely need to specify the range of valid data points though. – xnor Aug 16 at 11:11
• If you need an extra bit for rev number, the simplest solution I can see is combining days and years: allocate 10 bits for "days since 2019-01-01" (allowing for 5y, 220d (after taking into account 2 leap years)), which leaves a 6th bit for rev number. – GammaFunction Aug 18 at 12:20
• @GammaFunction I though of that, but that takes 11bits, not 10... or is my math way off? – pinkfloydx33 Aug 18 at 12:28
• @pinkfloydx33 Your math is right, I was wrong... The highest unsigned value in 10 bits is 2^10 - 1. By some wolframalpha searches, it would roll over on 2021-10-21. This gives you close to 3 years of 64 builds per day. and uses all your bits. So you would have to give up some of those builds for more days, or give up some of those days for more builds, or just assign all 16 bits to the build revision. Finding an algorithm which fits between 32 builds and 64 builds and that sorts could be interesting. – GammaFunction Aug 18 at 12:48
• If you have 14 bits for day and revision number, you have 1<<14 = 16384 possibilities. Dividing by 366 gives 44.7 (call it 44 !) possibilities for the revision number. So you can pack into 14 bits as day*44 + revision But personally I would pack into 14 bits as revision * 366 + day. Because you know you need 366 possibilities for the day, but you don't know how many revisions you need. If you end up with less than 22, you can use the unused bit to extend the year field in future (4 years sounds very short to me.) Decoding is by integer division and modulo. – Level River St Aug 27 at 1:05


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# SE(3)-DiffusionFields: Learning cost functions for joint grasp and motion optimization through diffusion

## Highlights

• learning task-space, data-driven cost functions as diffusion models
• Cross-entropy or Contrastive divergence
• try to create hard discr. regions in the modeled data -> this leads to large plateaus in the learned field with zero or noisy slope regions
• it is common to rely on task-specific samplers that first generate samples close to low cost regions (??)

Think about a cost function that involves multiple objective.
Such functions are typically computed with cross-entropy or contrastive divergnce.
These create hard discriminating regions in the modeled data, leading to zero gradient in the region.
-> Common solution is to rely on task-specific samplers that provides samples from the low-cost regions before optimization.

Instead, the proposed method forms a smooth cost function that provides informative gradients in all the region.

To train a grasp pose generation model, they use Acronym dataset.
It's a large scale dataset that contains pairs of grasp pose vs grasp success data for many different simulated objects.

## Contributions

1. learning smooth cost functions (i.e., the model that can provide informative gradient in the entire region) in SE(3) as diffusion models
• Sampling from SE(3) space is not trivial. They provide some mathematical foundation for that
1. a single gradient-based optimization framework for jointly resolving grasp and motion generation
• Their method can generate the grasp and a trajectory to reach there at the same time

## Background of Diffusion Models

They base their method on DSM: Denoising Score Matching, and sample from the model via Langevin MCMC.

## Gaussian Distribution on SE(3) Lie Group

After massaging some equations in SE(3) Lie Group, they reperesent the proabability of a grasp \mathbf{H} \in \text{SE}(3) as:

q(\mathbf{H} | \mathbf{H}_\mu, \Sigma) \propto \exp \big(-0.5 \| \text{Logmap}(\mathbf{H}_\mu^{-1} \mathbf{H})\|^2_{\Sigma^{-1}} \big),

where \mathbf{H}_\mu \in SE(3) is the mean and \Sigma \in \mathbb{R}^{6\times6} is the covariance matrix.
Logmap: SE(3) \rightarrow \mathbb{R}^6 projects an SE(3) pose to a 6-dim vector.

## SE(3)-Diffusion Fields (SE(3)-DiF)

mapping from a query point \mathbf{H} \in SE(3) to a scalar value e \in \mathbb{R}

e = E_\theta(\mathbf{H}, k),

where k is diffusion timestep.
Other parts are identical to DSM except that they work in SE(3) space.

## Training SE(3)-GraspDiffusionFields

• They assume the pose of the object is known
• They learn a latent feature for every object (similar to DeepSDF: Deep Signed Distance Field)
• They jointly learn the SDF of an object and grasp diffusion model
• They don't use grasp as input, but they rather use a fixed set of N points around the grasp's center to inform the grasp pose

Setup & Architecture

1. They pre-define a fixed set of N 3D-points around the grasp's center (\mathbf{x}_g \in \mathbb{R}^{N \times 3}; grasp frame)
2. Given a grasp pose (\mathbf{H}^w_g) in world frame, they transform the points to world frame (\mathbf{x}_w = \mathbf{H}^w_g \mathbf{x_g} \in \mathbb{R}^{N \times 3}; world frame)
3. Then they use the pose of object m (\mathbf{H}_w^{o_m}) to transform the points again to the object frame (\mathbf{x}_{o_m} = \mathbf{H}^{o_m}_w \mathbf{x}_w \in \mathbb{R}^{N \times 3}; object frame)
4. Encoder F_\theta takes in shape code \mathbf{z}_m \in \mathbb{R}^z and the points in object frame \mathbf{x}_{o_m} \in \mathbb{R}^{N \times 3} and output SDF prediction (scalar for each point) and additional features \psi \in \mathbb{R}^{N \times \psi}
5. Decoder takes both SDF prediction and features, and output energy (scalar)

TODO: I should just draw a figure by myself.

Training Objective

\mathcal{L} = \mathbb{E}_{(o_m, \mathbf{H}^w_g) \sim \rho_{D_\text{grasp}}} \big[ \mathcal{L}_\text{dsm} (\mathbf{H}^{o_m}_{w}, \mathbf{H}^{w}_g, z_m, \theta) \big] + \mathbb{E}_{(\mathbf{x}_o, o_m) \sim \rho_{D_\text{sdf}}} \big[ \mathcal{L}_\text{sdf}(\mathbf{x}_o, \text{sdf}_{o_m}, z_m, \theta) \big]
• o_m: object
• z_m \in \mathbb{R}^z: latent code of the object shape (SDF encoding)
• \mathcal{L}_\text{dsm}: Denoising Score Matching loss
• \mathbf{H}^w_g \in SE(3): grasp pose in world frame
• \mathbf{H}^{o_m}_{w} \in SE(3): object pose in world frame (during training, it's identity because it doesn't matter)
• \mathcal{L}_\text{sdf}: SDF prediction loss
• \mathbf{x}_o \in \mathbb{R}^{N \times 3}: a random 3D point in object frame
• \text{sdf}_{o_m}: \mathbb{R}^3 \rightarrow \mathbb{R}^1: Sign Distance Field

## Grasp and motion generation

They try to find the minimum cost trajectory \tau^*:

\tau^* = \arg \min_\tau \mathcal{J}(\tau) = \arg \min_\tau \sum_j w_j c_j (\tau)
• c_j(\tau): a cost function
• w_j > 0: weights

The grasp generation model (SE(3)-DiF) forms one of the cost functions.
With that, this optimization can take into account grasping pose.

Cost function for a grasp pose

Cost function with SE(3)-DiF
$$c(\mathbf{q_t}, k) = E_\theta (\phi_{ee} (\mathbf{q_t}), k)$$
, where \phi_{ee}: \mathbb{R}^{d_q} \rightarrow \text{SE}(3) is forward kinematics model.

Intuitively, this cost function provides low cost to those robot configurations that lead to good grasps.

How to solve the minimization / optimization problem? --> Diffusion reverse process!
Note that this does NOT involve any training, this is simply the reverse process of diffusion.

1. Define the distribution over trajectories as q(\mathbf{\tau}|k) \propto \exp(- \mathcal{J}(\mathbf{\tau}, k)) (see Planning as Inference)
• This q(\mathbf{\tau}|k) will be the target distribution
1. Run reverse diffusion process: Langevin diffusion process
\mathbf{\tau}_{k-1} = \mathbf{\tau}_k + 0.5 \alpha^2_k \nabla_{\mathbf{\tau}_k} \log q(\mathbf{\tau}|k) + \alpha_k \epsilon, \epsilon \sim \mathcal{N}(\mathbf{0}, \mathbf{I})

A small caveat: all cost function must be differentiable to compute \nabla_{\tau_k} c_{n_s}

Scratch

Smooth function --> the cost function exposing informative gradients in the entire space.
They learn smooth cost functions in the SE(3) robot's workspace -> task-specific costs.

Acronym dataset

The resulting models allow to move samples to the low-cost regions via inverse diffusion process.

Combining their learned diffusion model for 6D grasp pose generation with other smooth costs (trajectory smoothness, collision avoidance cost).

## Contributions

1. learning smooth cost functions in SE(3) as diffusion models
2. A single gradient-based optimization framework for grasp and motion generation

## Experiments

• Picking with occlusions
• Picking and reorienting an object
• pick and place in shelves

## Terms

• tangent space
tangent space at the identity is called Lie algebra.
• logmap (SE(3) -> R^6) and expmap (R^6 -> SE(3))

## Q & A

• what is the main goal of that paper?
• what data format they use as input?
• what assumptions do they make (object centric/dense features)?
• What different assumption do we want to make?
• Is it right/wrong/preferable?
• What did they show in figure 1?
• What did they show in figure 2?
• What did they show in exp 1?
• How did they show it?
• Compared to what?
• What is the real world demo?
• Why is this demo difficult? (they did 6 DOF)


text:
Wildcards in script control exclusions Skip Navigation

# Wildcards in script control exclusions

You can use the asterisk (*) as a wildcard when specifying exclusions in the
Script Control
tab.
Using wildcards in script control exclusions reduces the number of alerts displayed in your console while allowing users to run certain scripts that match the exclusion path and filename. For example, you can exclude a specific script by using its full name, or you can use the wildcard to match a group of scripts that share a similar name.
Although the use of wildcards in exclusions provides flexibility, it can also lower your security stance if your exclusions are too broad. For example, avoid excluding entire folders such as
/windows/temp
. Instead, use a wildcard while specifying the full or partial filename of the script that you want to exclude (for example,
/windows/temp/myscript*.vbs
).
The following table describes the rules of script control exclusions:
Item
Description
Supported wildcard characters
Only the asterisk (*) is supported as a wildcard for script control exclusions.
The wildcard represents one or more characters.
Unix-style slashes
If you are using wildcards, exclusions must use Unix-style slashes (even for
Windows
systems).
Example:
/windows/system*/*
Folder exclusions
When you want to exclude a folder, the exclusion must have a wildcard at the end of the path to distinguish the exclusion as a folder (and not a file).
For example:
• /windows/system32/*
• /windows/*/test/*
• /windows/system32/test*/*
File exclusions
When you want to exclude a file, the exclusion must end with a file extension to distinguish the exclusion as a file (and not a folder). For example:
• /windows/system32/*.vbs
• /windows/system32/script*.vbs
• /windows/system32/*/script.vbs
• One wildcard per level.
• So /folder/*/script.vbs matches \folder\test\script.vbs or \folder\exclude\script.vbs but does not work for \folder\test\001\script.vbs. This would require either /folder/*/001/script.vbs or /folder/*/*/script.vbs.
• The wildcard would need to persist down per level to where the script resides.
• Two or more wildcards per level are not allowed. For example, /*/folder/*file*.ext is not allowed.
For each folder level, you can use one wildcard only.
• Example,
/*/folder/*file*.ext
is not allowed.
Each wildcard represents one folder level only. The number of folder levels represented in the exclusion must match the level of the file that you are trying to exclude.
• For example, if you are trying to exclude
\test\level1\level2\script.vbs
, use
/test/*/*/script.vbs
(not
/test/*/script.vbs
).
Process exclusions
Process exclusions with a wildcard must have a file extension to distinguish it as a process exclusion (and not a folder).
To specify a process regardless of the directory that it's in, refer to the following examples:
• /my*.exe
(local drive)
• //my*.exe
(network drive)
To specify a process that's in a specific directory, refer to the following examples:
• /directory/child/my*.exe
(local drive)
• //directory/child/my*.exe
(network drive)
Examples of full and partial matches in exclusions
Wildcards support full and partial exclusions.
• /folder/*/script.vbs
• /folder/test*/script.vbs
Absolute paths
Absolute paths are not supported in script control exclusions.
Relative paths
If you can identify a common relative path, you can exclude Universal Naming Convention (UNC) paths with a wildcard. For example, if you use device names in a path such as "DC01" to "DC24":
• /dc*/path/to/script/*
Network paths
Network paths can be excluded. For example:
• //hostname/application/*
• //host*/application/*
• //*name/*/application/*
• //hostname/*


text:
# ATNF VLBI Wiki

### Site Tools

lbaops:lbanov2007:recentchanges

# Differences

This shows you the differences between two versions of the page.

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November 13, 2007, at 05:57 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vx012batlog]]  . . . November 13, 2007, at 09:41 AM by [[.:.:.:.:.:.:.:.:.:.:.:~guest]] + *  [[lbaops:lbanov2007:v190kcdlog]]  . . . November 13, 2007, at 08:09 AM by [[~breid]] + *  [[lbaops:lbanov2007:v190kmplog]]  . . . November 13, 2007, at 01:55 AM by [[~guest]] + *  [[lbaops:lbanov2007:v190kpalog]]  . . . November 13, 2007, at 01:53 AM by [[~guest]] + *  [[lbaops:lbanov2007:vc038cdlog]]  . . . November 12, 2007, at 07:59 PM by [[~breid]] + *  [[lbaops:lbanov2007:v254acdlog]]  . . . November 12, 2007, at 07:22 PM by [[~breid]] + *  [[lbaops:lbanov2007:vc038holog]]  . . . November 12, 2007, at 07:10 PM by [[~breid]] + *  [[lbaops:lbanov2007:vx012b]]  . . . November 12, 2007, at 10:41 AM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:v254amplog]]  . . . November 12, 2007, at 09:36 AM by [[~guest]] + *  [[lbaops:lbanov2007:v254apalog]]  . . . November 12, 2007, at 09:35 AM by [[~guest]] + *  [[lbaops:lbanov2007:v186apalog]]  . . . November 12, 2007, at 09:21 AM by [[~guest]] + *  [[lbaops:lbanov2007:v186aatlog]]  . . . November 12, 2007, at 09:19 AM by [[~guest]] + *  [[lbaops:lbanov2007:v186amplog]]  . . . November 12, 2007, at 09:17 AM by [[~guest]] + *  [[lbaops:lbanov2007:v254aatlog]]  . . . November 12, 2007, at 09:13 AM by [[~adeller]] + *  [[lbaops:lbanov2007:v186acdlog]]  . . . November 12, 2007, at 09:05 AM by [[~breid]] + *  [[lbaops:lbanov2007:v254a]]  . . . November 11, 2007, at 11:59 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vc036hhlog]]  . . . November 11, 2007, at 08:31 PM by [[.:.:.:~hartrao]] + *  [[lbaops:lbanov2007:v252apalog]]  . . . November 11, 2007, at 06:01 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:v252acdlog]]  . . . November 11, 2007, at 05:01 PM by [[~breid]] + *  [[lbaops:lbanov2007:v252amplog]]  . . . November 11, 2007, at 04:52 PM by [[~adeller]] + *  [[lbaops:lbanov2007:v252aatlog]]  . . . November 11, 2007, at 04:52 PM by [[~adeller]] + *  [[lbaops:lbanov2007:vc037]]  . . . November 11, 2007, at 03:57 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:v252ahhlog]]  . . . November 11, 2007, at 01:41 AM by [[~hartrao]] + *  [[lbaops:lbanov2007:vc035bhhlog]]  . . . November 10, 2007, at 09:05 PM by [[~hartrao]] + *  [[lbaops:lbanov2007:vc035batlog]]  . . . November 10, 2007, at 05:05 PM by [[~adeller]] + *  [[lbaops:lbanov2007:vc035b]]  . . . November 10, 2007, at 04:04 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vt11f1]]  . . . November 10, 2007, at 12:30 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:v190jatlog]]  . . . November 10, 2007, at 04:44 AM by [[~guest]] + *  [[lbaops:lbanov2007:v190jpalog]]  . . . November 10, 2007, at 01:20 AM by [[~guest]] + *  [[lbaops:lbanov2007:v190jmplog]]  . . . November 10, 2007, at 01:19 AM by [[~guest]] + *  [[lbaops:lbanov2007:vc034atlog]]  . . . November 09, 2007, at 12:57 PM by [[~adeller]] + *  [[lbaops:lbanov2007:v190j]]  . . . November 07, 2007, at 01:32 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vc039]]  . . . November 06, 2007, at 03:39 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:v186a]]  . . . November 06, 2007, at 12:16 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vc040]]  . . . November 05, 2007, at 02:30 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vc036]]  . . . November 05, 2007, at 02:17 PM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vc038]]  . . . November 05, 2007, at 11:27 AM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:vc034]]  . . . November 05, 2007, at 11:20 AM by [[lbaops:~chris:phillips]] + *  [[lbaops:lbanov2007:v190k]]  . . . October 31, 2007, at 02:49 PM by [[~adeller]] + *  [[lbaops:lbanov2007:v157c]]  . . . October 30, 2007, at 08:07 PM by [[.:~stingay]] +


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# Changing member data types

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Jumpster    122
I want to create a set of classes like shown below:
  class InputDevice { .... }; class JOYSTICK : public InputDevice { protected: LPINPUTDEVICE2 device; .... }; /////////////////////////////////////////////// /////////////////////////////////////////////// // Force Feed-back supported joystick. // If Force FeedBack is not supported by the // Joystick, default to JOYSTICK class behavior. // class FEEDBACK : public JOYSTICK { protected: LPINPUTDEVICE7 device; .... };
Currently I have a LPINPUTDEVICE2 device value and added an LPINPUTDEVICE7 feedback value to the FEEDBACK version. Is there a way to do what I illustrated above? Regards, Jumpster Note: I am posting in two-forums because I don''t know if the solution would be DX specific or C++ general.

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Jumpster    122
Perhaps I am asking the wrong question here?

Let me try again:

I have a base class with a member variable of type "A". I want to inherit from that class, keep the same member variable name but change it to type "B".

Can that be done? If so, how?

Regards,
Jumpster

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Xai    1838
While I''m not sure that C++ wont let you do it ... try it and see ... i can guarantee you that the effect will not be what you are looking for.

assuming the compiler let you do this ... all you are doing is creating a second variable that hides the first. unlike functions ... there is no virtual variable feature to allow you to do anything usefull with this type of thing. see ... no matter if the variable in the base class is public, private, or protected ... the fact that it is declared there means storage and type are assigned there ...if you additionally define one with the same name in your derived class ...then you have a total of 2 ... and you would only be able to access the base class version like this A::device ... and anything you do to the derived class version B::device has absolutely no effect on the operation of Base class functions (unless they are virtual).

What you are really have to do to get the feature you want is use an abstract base class ... IJoystick ...without the device data member ... then a derived class for the old style joystick ... perhaps Joystick2 ... and another class Joystick7 ... which could either be a sibling of Joystick2, or could be derived from Joystick2 ... therefore not overriding members that do not change ...but the device member in Joystick2 should be PRIVATE if you wish it not to cause bad things when you write Joystick7 ...

Note: The names IJoystick, Joystick, and ForceFeedbackJoystick are better than the ones I used in the example.

Good luck ...feel free to ask for clarification