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Home ▶ Vol 79, No 1 (2020) ▶ Akinbinu
Tope R. Akinbinu
Discipline of Optometry, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
Kovin S. Naidoo
School of Optometry, University of New South Wales, Sydney, Australia
Samuel O. Wajuihian
Akinbinu TR, Naidoo KS, Wajuihian SO. Myopia control in the 21st century: A review of optical methods (2000–2019). Afr Vision Eye Health. 2020;79(1), a499. https://doi.org/10.4102/aveh.v79i1.499
Myopia control in the 21st century: A review of optical methods (2000–2019)
Tope R. Akinbinu, Kovin S. Naidoo, Samuel O. Wajuihian
Received: 04 Feb. 2019; Accepted: 13 Aug. 2019; Published: 09 Apr. 2020
Copyright: © 2020. The Author(s). Licensee: AOSIS.
Background: Without appropriate interventions, simple or low myopia can progressively get worse and lead to high myopia. Patients with high myopia are at a greater risk of developing retinal detachment, myopic macular degeneration, glaucoma and eventual blindness in some cases, and hence the reason for the global call for myopia control. Consequently, myopia in the 21st century is not only treated as a refractive error but an ocular disorder with potential negative consequences. Myopia control strategies include optical, pharmacological and behavioural methods. In this report, the effectiveness of optical methods of myopia control was reviewed.
Aim: The aim of the review is to evaluate and summarise existing knowledge on myopia control and provide recommendations to guide future studies.
Method: The review was conducted using online search engines including PubMed and Google Scholar. Articles published between 2000 and 2019 were included.
Results: For the optical methods of myopia control, under-correction has been found to be largely ineffective. However, a recent study shows that myopic children without correction had slower myopia progression (−0.75 D) than fully corrected children (−1.04 D) indicating a 28% reduction. Evidence from various studies indicates that bifocals and progressive addition lenses are not as effective as soft dual focus contact lenses or extended depth of focus contact lenses. Clinical trials indicate that single vision rigid gas permeable lenses did not slow myopic progression. Peripheral defocus lenses and orthokeratology were found to be approximately 50% effective across studies reviewed.
Conclusion: Peripheral defocus lenses and multifocal contact lens designs offer the most effective myopia control. Orthokeratology is equally effective but future designs should consider ways of minimising risks of complications with lens wear. More studies would be needed to better understand how under-corrected myopic eyes tend to progress faster, whereas myopic eyes without correction tend to progress slower. A holistic approach and combination of methods may offer the best form of myopia control in the 21st century considering the increase in near work activities and use of digital devices among the most vulnerable groups.
Keywords: myopia control; under-correction; bifocals; progressive addition lenses; contact lenses; orthokeratology.
The nurture theory on myopia development indicates excessive reading and near work activities during childhood as risk factors of abnormal axial length (AL) elongation, yet its onset and development is not clearly understood.1 Myopia, depending on its severity, can impair both distance and intermediate or near vision, and high myopia (≤ –5 D [dioptre]) is a cause of preventable blindness and vision impairment from myopic pathologies such as myopic macular degeneration, cataract, glaucoma, retinal tear as well as retinal detachment.2
The prevalence of myopia ranges between 1% and 78.4% across studies3,4,5,6,7,8,9,10 reported in the 21st century. Although myopia is more prevalent in East Asia than other parts of the world (Table 1)10, reports show that the world prevalence has grown from 1406 million in 2000 and could reach 4758 million by 2050 (50% of the world population) if proper control measures are not implemented.10 The increasing prevalence of myopia could be related to the considerable increase in the use of smartphones and computers since the beginning of the 21st century. In the United States, for example, a survey reveals that 41% of children spend three or more hours daily using digital devices and 66% of children have their own smartphone or tablet.11 This increased near work has been implicated in the development of myopia by some authors, while others argued that it is because of the fact that time on these devices keeps children inside and deprives them of time outdoors.12
TABLE 1: Estimated prevalence of myopia between 2000 and 2050.
The importance of research to control myopia cannot be overemphasised when one considers the potential complications of high myopia, increasing cost of health care and global loss of productivity associated with it.2,13 There is a need to reduce its onset and progression particularly in children younger than 14 years of age and a good understanding of myopia control methods is deemed necessary. The aim of this review is to evaluate and summarise existing knowledge on myopia control and provide recommendations to guide future studies. The objectives are:
to determine the most commonly used study design for myopia control
to determine the most effective optical methods for myopia control based on the existing literature
to document the limitations of previous studies
to make recommendations for future studies
In this report, the effectiveness of optical methods of myopia control was reviewed in the context of increased research and development in this space.
The review of literature on optical myopia control strategies in the 21st century was conducted using online search engines including PubMed and Google Scholar. The identified copies were retrieved from online journals or from hard copies as appropriate. Furthermore, some articles were identified from other articles' reference lists and retrieved accordingly. Articles published in the English language with the keyword 'myopia control' and medical subject heading (MeSH) terms 'contact lenses' (CLs), 'spectacles' and 'prevention' were used. Articles published between 2000 and 2019 were considered. A total of 2507 studies were generated and 69 studies were used for analysis. Male and female genders (age 6–25 years) were included in the review. Studies reviewed include randomised control trials, population and school-based surveys. Animal studies were excluded from the review.
Ethical considerations
This article followed all ethical standards for research without direct contact with human or animal subjects.
Myopia progression extends through childhood until the late teenage years. However, the rate of myopic progression differs considerably from one child to another.14 The creation of a myopigenic environment in urban cities in recent times cannot be dissociated from the increased prevalence of myopia across the world. The use of computers, phones, tablets and computer games has become more popular among children of today.11 Prolonged reading on computers and near work has been associated with myopia.15,16 This deprives children of spending quality time outdoors.12 Research suggests that increased levels of exposure to outdoor light significantly reduce the incidence of myopia in school children. This is possibly related to the restrictive role of dopamine on eye growth and myopia development.17,18 However, it was reported that it only has a significant effect on the incidence of myopia with little effect on myopic progression.19,20,21 Consequently, efforts have been made to encourage more outdoor play in children to reduce the incidence of myopia.22,23 In spite of other forms of myopia control (such as pharmacological agents) indicating a 50% reduction in myopia progression in children, optical aids remain a viable means of control because they are a common form of myopia correction. This article reviews only the optical methods. The optical interventions reviewed include under-correction with single vision lenses (SVLs), bifocals, progressive addition lenses (PALs), CLs and orthokeratology (Ortho-K).
Under-correction with single vision lenses
Under-correction is a method of deliberately reducing the full myopic prescription in order to slow myopic progression. Adler et al.24 under-corrected 25 myopic children (age 6–15 years). Twenty-three of them were fully corrected, while 25 of them were under-corrected by 0.50 D. The baseline myopia was −1.06 D to −4.5 D (mean −2.82 D) for the fully corrected group and −1.37 D to −5.30 D (mean −2.95 D) for the under-corrected group. The results for both groups indicate that myopes with −3.00 D or more at baseline had faster progression of myopia than those less than −3.00 D. After 18 months, the progression of myopia was 4.4% in the children who were under-corrected but this difference was not statistically significant.
Li et al.25 followed 1769 Chinese children (age 12 years) for 1 year. Out of 253 myopic children with spectacles, 47.4% were under-corrected by at least two lines of visual acuity and 52.6% were fully corrected. It was reported that the under-correction group had higher baseline myopia than the full correction group and the result did not show any significant difference in myopia progression or AL elongation. A limitation to the study was the 1-year follow-up which may not be enough to notice a significant change in progression. A study by Chung et al.26 in Malay and Chinese children (aged 9–14 years) indicated an increase in myopia progression of 0.23 D over a 2-year period. They reported similar baseline data including a mean myopic refractive error of −2.68 D in both under-corrected and fully corrected groups. The distance refraction in juvenile myopic patients was under-corrected by 0.75 D and it resulted in a rapid increase in myopia progression (30%) which correlated with changes in AL and confirms that under-correction increases progression.
However, a recent study by Sun et al.27 investigated the effect of no correction and full correction in Chinese myopic children with an average age 12.7 years. The children without correction had slower myopia progression (27%) than fully corrected children after two years. Baseline myopia with cycloplegic refraction was −3.03 D for full correction and −1.31 D for uncorrected. Myopia progression decreased significantly with an increasing amount of under-correction in all children. Studies by Li et al.25 and Sun et al.27 are similar in terms of age group and both studies involved Chinese children. The other studies24,26 reviewed involved a younger population. Although Sun et al.27 reported selection bias and differences in some baseline characteristics that may affect their results, the amount of under-correction in their study was greater (1.31 D) than the under-correction in other studies by Adler et al.24 and Chung et al.26 (0.50 D and 0.75 D, respectively). Besides, the purpose of the study by Sun et al.27 is the effect of no correction on myopia progression. It was explained that the larger the amount of under-correction, the slower the myopic progression based on myopic defocus theory.27 As Adler et al.24 reported that higher myopic error at the baseline leads to faster progression, more studies with similar baseline characteristics would be needed to monitor the rates of myopia progression and the amount of under-correction given the conflicting results.
Bifocal glasses may make up for the reduced accommodative response commonly observed in esophoric myopic children.28 In a randomised trial of the effect of SVLs versus bifocal lenses (BFLs) in children (age 6–12.9 years), Fulk et al.29 demonstrated that BFLs reduced myopia progression by 0.25 D compared to SVLs in a period of 30 months. Myopia progression was reduced by 20% with BFLs compared to SVLs and the use of bifocals in myopic esophoric children slows progression by a slight degree. Their study suggests that BFLs only show a weak effect on myopia control.
Cheng et al.30 noted that executive BFLs with a larger add area than normal BFLs might be more effective at reducing myopia progression. In addition, large segment executive BFLs produced a myopic shift in the peripheral image zone for the inferior field and the central field.30 The addition of base-in prism to BFLs did not make a significant difference.31 In a 3-year randomised clinical trial, Cheng et al.30 randomly assigned Chinese–Canadian children (age 8–13 years) to three groups (SVLs, +1.50 D executive BFLs and +1.50 D executive BFLs with a 3 prism dioptre). The Howell–Dwyer near phoria card was used to measure near horizontal phoria through the distance correction. The rationale for using add +1.50 D and 3 prism dioptre was based on the outcome of a previous study32 where a graphical method was used to determine the best lens and prism power that neutralises the lag of accommodation (LA) and phoria. With a mean baseline myopia of −3.08 D, the average myopia progression over 3 years was reported as a spherical equivalent (SE) of −2.06 D in the SVL group, an SE of −1.25 D in the BFL group and an SE of −1.01 D in the prismatic BFL group, indicating a 39% and 51% reduction in myopic progression in the BFL and prismatic BFL groups, respectively, as compared to the SVL group. The study concluded that bifocal spectacles can reduce myopia progression with an annual progression rate of approximately 0.50 D after 3 years. Myopic children with low lags of accommodation benefitted more from the use of prismatic bifocals possibly because of the reduction in convergence and lens-induced exophoria by the addition of a base-in prism.
Progressive addition lenses
Progressive addition lenses feature a progressive change in power from the distant, intermediate to near viewing portions without demarcations. In 469 subjects (age 6–11 years), Gwiazda et al.33 investigated the effect of PALs (with +2.00 add) compared to SVLs on myopic progression. The baseline myopia was −2.40 D (mean SE) for PALs and −2.37 D (mean SE) for SVLs. Cycloplegic refraction was conducted over a period of 3 years and the mean increase in myopia was 1.28 D (PAL) and 1.48 D (SVL). There was a modest statistically significant difference of 0.20 D (13.5%) between PALs and SVLs only in the first year which remained the same in subsequent years.33 The authors, however, noted that the difference may not make a meaningful impact in clinical practice.
Hasebe et al.34 in a randomised, double-masked, crossover trial in Japanese children (age 6–12 years) concluded that the use of PALs compared to SVLs slowed myopia progression statistically but with a clinically non-significant treatment effect of 0.17 D for 18 months and a mean reduction rate of 15%. Baseline myopia (mean SE) was −3.17 D for the PAL group and −3.31 D for the SVL group. It was noted that early application of PALs could be more beneficial at lower degrees of myopia and a younger age. In another study,35 they compared positively aspherised PALs (+1.00 add and +1.50 D add) with SVLs in Chinese and Japanese children (age 6–12 years). The baseline myopia was −2.55 D (SVL), −2.52 (add +1) and −2.80 (add +1.5). Myopia significantly progressed in three groups. Mean myopia progression was −1.38 D (SVL group), −1.32 D (+1.00 D add group) and −1.19 D (+1.50 D add group). The treatment effect with positively aspherised PALs with +1.50 D add was 31% (0.24 D). Reduction in myopia progression mostly occurred in the first 12 months with no significant efficacy in the second year. The high positive aspherisation of the distance zone added to PALs does not improve their therapeutic efficacy as compared to the conventional PALs with the same addition of power.
Some studies36,37 have identified LA as a risk factor for the progression of myopia, although other studies38,39,40 reported contrary findings. A possible reason is that higher LA presents with higher accommodative demands in myopes who exhibit the tendency to have sustained periods of retinal defocus consequently leading to AL elongation.36 Myopic defocus (creation of images in front of the retina) inhibits eye growth and it is the major principle behind some optical myopia control strategies.41 Hence, the reason PALs are introduced to help reduce retinal defocus during near tasks. Reports also indicate that the more esophoric a myope is, the more the addition needed to reduce myopic progression, hence the reason esophoric myopes benefit more from myopia control trials with PALs. However, a major limitation of studies involving PALs for myopia control is the tendency of children to avoid reading through the near add.42,43 Nevertheless, the phoria status of myopic children needs to be considered for near additions to be effective.
Schilling et al.44 compared LA in myopes (age 18–25 years) wearing SVLs and four different designs of PALs at different near viewing distances (25 cm, 33 cm and 40 cm). The designs differ in near zone width and the horizontal power gradients around the near zone. The LA was measured with subjects fixating a near card. A formula from a previous study45 was used to calculate the LA (LA = accommodative demand – accommodative response). Their results indicated that there was no significant difference in LA between PALs with narrow and wide segments. The LA was more reduced with the negative horizontal mean power gradient PALs. Therefore, the designs of the reading portion of PALs should consider the additional power and the distribution of the peripheral power in the reading portion which may play a significant role in myopia control. Leads of accommodation observed with bifocal CLs in some myopes could be responsible for their beneficial effects on myopia control.46 However, Weizhong et al.47 assume that the effectiveness of bifocal or multifocal lenses on myopia progression is an improvement in accommodative accuracy which consequently reduced the near lag. Their findings suggest that reducing the amount of near lag in myopes has no clinical significance.
Peripheral defocus spectacle lenses
A new myopia control lens, defocus-incorporated multiple segments (DIMS®), was launched by Hoya Vision Care and Hong Kong Polytechnic University (HKPU) in 2018. The lens works on the theory of myopia defocus by projecting images on and in front of the retina simultaneously.48,49 From clinical research with Chinese children (age 8–13 years) and the myopia range from −1.00 D to −5.00 D, Lam et al.41 used a myopic defocus of +3.50 D and DIMS® lenses which were found to reduce myopic progression by 52% compared to children wearing single vision (SV) spectacle lenses over two years.41 The mean baseline myopia was similar in both groups (−2.93 D for DIMS and −2.70 D SVL). The authors reported a lower dropout rate (13%) and an improvement in wearing time of the DIMS lens (up to 15 hours per day) compared to the Defocus-Incorporated Soft Contact Lens (DISC CL) (42% dropout rate, 8 hours per day) used in a previous study. The obvious difference is the ease of wear of spectacles over CLs.
Contact lenses may produce better myopia control than single vision spectacle lenses. One possible reason is that the optical treatment area of CLs affects a larger part of the visual field than the peripheral treatment area of spectacle lenses.50 In addition to the flattening of the cornea that may reduce myopic refractive error, CLs follow the eye movement and ensure a sustained therapeutic effect unlike spectacle lenses where the eye movements may result in a loss of the therapeutic effect.51,52 However, a randomised clinical trial by Katz et al.53 in Singaporean children (age 6–12 years) concluded that rigid gas permeable (RGP) CLs did not make a significant difference in myopia progression, even among regular users. Cycloplegic subjective refraction was used to assess children for refractive errors (spherical equivalent refraction [SER] from −1.00 D to −4.00 D). The children assigned to RGP contacts remained more myopic by 3.7% than those in the spectacle group. The AL increased by 0.84 mm in the CL group and 0.79 mm in the spectacle group indicating a 6% increase in AL. The CL and myopia progression study in a 3-year trial compared the effect of RGPs and soft CLs in slowing the progression of moderate myopia. There was a clinically significant difference. The RGP lenses offer more control because of the corneal flattening, a phenomenon similar to the effect obtained with the use of Ortho-K but this was not maintained after cessation of RGP wear.51,54
Soft bifocal or dual focus CLs create a myopic peripheral defocus to slow the progression of myopia by approximately 50% across the studies reviewed.55,56,57 In a randomised control trial of 40 myopic children with similar baseline characteristics (mean SER of −2.71 D, age 11–14 years), Anstice et al.55 compared a dual focus CL (concentric design of +2.00 D peripheral portion) with a single vision distance CL between two eyes of the same subject for 10 months. The same procedure was repeated for the other eye for another 10 months. The results indicate approximately 30% reduction of myopia in 70% of the eyes wearing the dual focus lens. There was no significant difference in the contrast sensitivity and visual acuity with both lenses during the trial. This suggests that the sustained myopic defocus with bifocal CLs can reduce myopia progression without affecting visual function.
Walline et al.57 fitted children (age 8–11 years) with soft multifocal CLs (SMCLs) with +2.00 D add and concluded that SMCL wear resulted in a 50% reduction in myopia progression as compared to a historical single vision CL control group. Sankaridurg et al.56 fitted novel CL with progressive increase in addition on Chinese children (age 7–14 years). The estimated progression in spherical myopia was 34% less than with spectacle lenses. They concluded that reducing peripheral hyperopia can have a significant effect on central refractive development and consequently slows myopic progression.
Moore et al.58 investigated the effect of a commercially available spherical soft CL on peripheral defocus of young adult myopic eyes (mean age: 24 years). There were differences in peripheral defocus profiles in different brands (designs) of CLs. The four brands of soft CLs used caused a negative change in spherical aberration. The CLs inducing less negative spherical aberration changes were associated with a less hyperopic change in relative peripheral defocus. Although the result did not reveal how much myopic change in peripheral defocus is needed to cause a clinically meaningful change in myopia progression, it can be inferred that higher power CLs increased peripheral myopic defocus and soft CLs provide better peripheral defocus than spectacle lenses. In other words, the type and design of CL (including aspheric optics and optic zone diameter) would significantly influence the role of peripheral defocus on myopia progression.
Peripheral defocus contact lenses
The DISC CL (DISC®) is a novel bifocal CL with a concentric rings pattern to allow myopic retinal defocus (with add +2.50 D) and at the same time maintain clear vision through the central portion.59 Lam et al.59 in a 2-year double blind randomised control trial (RCT) on Hong Kong Chinese children (age 8–13 years) compared the DISC® with SVCL group. Children enrolled had myopia of −1.00 D to −5.00 D. The mean baseline myopia was −2.86 D and −2.79 D in the DISC® and SVCL groups, respectively. The DISC® reduced myopia progression by 25% and AL by 31% in 2 years. Wearing time is a major factor influencing myopia-controlling property of the DISC® with increased wearing time indicating up to 50% reduction for subjects wearing the CL 5 h or more per day. More studies will be needed to explore the benefits of the DISC® lens on a large scale as a high dropout rate (42%) was a major limitation of the study.
In a more recent study comprising 508 Chinese children (age 7–13 years), with cycloplegic autorefraction (SER from −0.75 to −3.50 D), Sankaridurg et al.60 used novel CLs that induced retinal myopic defocus. Compared to SVCLs in compliant wearers (at least 6 days a week), there was a 26% – 43% reduction in myopic progression. The mean baseline myopia was −2.29 D for the control group which was not significantly different from the four groups of test peripheral defocus contact lenses (PDCLs) with different lens designs. Beside the difference in relative peripheral plus power (+1.50 D, +2.50 D) of the test PDCLs, some were also designed to create myopic defocus over a large area. There was no significant control effect across the four test PDCLs.
Orthokeratology is a rigid CL (also known as corneal refractive therapy) usually worn overnight to reduce or correct myopia by flattening the anterior portion of the cornea and taken off during the day.61 Orthokeratology significantly reduces eye growth and can produce corrective and control effects on myopia. This is largely attributed to a relative peripheral myopic defocus that slows the progression of myopia significantly but there could be variations in changes in AL among myopic children.62,63 Santodomingo-Rubido et al.64 conducted cycloplegic autorefraction and compared AL growth between white European children wearing Ortho-K and SVL (age 6–12 years, SER from −0.75 D to −4.00 D) over two years. The baseline myopia was similar in both the Ortho-K (SER −2.15 D, AL 24.4 mm) and SV (SER −2.08 D, AL 24.22 mm) groups. The increase in AL in the Ortho-K group was 0.47 mm and the SVL group was 0.69 mm. The study indicated that Ortho-K wear reduces AL elongation by a significant amount (32%) when compared to SVLs. In a similar study, Kakita et al.65 also reported 36% reduction in AL.
Cho et al.66 in a single-masked randomised clinical trial in children (age 6–10 years) randomly assigned to wear Ortho-K or SVLs for two years concluded that Ortho-K slows AL elongation by 43% compared to SVLs. Average AL elongation was 0.36 mm in the Ortho-K group and 0.63 mm in the control group. Myopic progression was significantly greater in younger children (7–8 years) than older children (9–10 years) in both groups. Chen et al.67 also reported a 52% reduction in AL compared to controls in myopic children (age 6–12 years) with moderate-to-high astigmatism.
Cho et al.68 compared changes in AL elongation spanning a period of 14 months in subjects (age 8–14 years) who discontinued and later resumed Ortho-K with those who wore spectacles after a 2-year myopia control study. It was reported that discontinuation of Ortho-K wear at or before the age of 14 years could lead to a more rapid elongation of AL and the resumption of spectacles after stopping Ortho-K for 6 months significantly reduced AL elongation. A combination of partial reduction (PR) Ortho-K and SVLs (daytime wear) was used by Charm et al.69 in myopic children (age 8–11 years). The Ortho-K was a custom-made four-zone design and the residual refractive errors were corrected with SVLs. Results indicated that PR Ortho-K slowed myopic progression by a significant amount. The AL elongation was 63% slower in the PR Ortho-K group than the SVL group. A study by Lin et al.54 compared Ortho-K with atropine 0.125%. There was an increase in myopia of 0.28 D in the Ortho-K group and 0.34 D per year in the atropine group indicating a 17.6% increase. High myopes benefitted more from Ortho-K and atropine than low myopes.
Zhu et al.61 compared the effect of Ortho-K and spectacles on myopia progression in Chinese children (age 7–14 years). The mean refractive error for the Ortho-K group after two years was −1.05 D compared to −5.60 D in the spectacle group (81% increase). The increase in AL was 51% slower in the Ortho-K group than the spectacle group after 24 months. Axial length elongation was slower by 49% in low myopes, 59% in moderate myopes and 46% in high myopes. Myopic progression was much slower (61%) in younger myopes than older myopes (35%). It can be inferred from this study that Ortho-K significantly reduces myopia progression as compared to SVLs. However, most of the studies reported above are short-term studies with an average span of two years.
To further assert the effectiveness of Ortho-K, a long-term study (seven years) compared the AL growth in white European children (aged 6–12 years, SER −0.75 to −4.00 D) wearing Ortho-K to children wearing SV spectacle lenses and revealed a 42% reduction in AL for the Ortho-K group after 12 months, 41% after 24 months and 33% after 84 months.70 Although the mechanism by which Ortho-K reduces myopic progression is not clear, there is a flattening of the central corneal area that simultaneously steepens the mid-peripheral zone. This results in the creation of peripheral myopic defocus which may reduce the visual feedback for AL elongation.71,72,73
In this report, the optical methods of myopia control were reviewed including under-correction, bifocals, PALs, multifocal CLs and Ortho-K. Progression with the under-correction method is not clearly understood. Studies by Adler et al.24 and Chung et al.26 reveal an increase in myopic progression with under-correction. A possible reason is that under-correction will make myopic eyes experience relative peripheral hyperopia which may contribute to myopia progression. Under-correction may also change the viewing behaviour of children which may make them participate less in distant vision tasks and spend less time outdoors. Spending less time outdoors has been indicated as a risk factor in the development of myopia.19,20,22 This has been linked to the restrictive role of the neurotransmitter dopamine on eye growth and myopia development17,18 which implies that lack of outdoor light leads to lesser dopamine secretion.
Studies by Gwiazda et al.,33 Hasebe et al.34,35 and the Correction of Myopia Evaluation Trial (COMET 2)74 that used PALs for myopia control found a reduction in myopia progression of about 30% in the first year of the trial when compared to SVLs, but the effect was reduced in subsequent years. A common limitation of some studies reviewed is the assumption that a particular power (addition) for PALs exerts the same myopia control effect on all children. Research shows that esophoric myopes could benefit from more power (addition) than exophoric myopes to control myopia.40
For bifocal CLs, a study by Aller et al.52 shows a large difference (myopia control rate of 72%) compared to previous studies (average control rate of 50%), a possible limitation of the study is that the generalisability of the findings was limited as most participants had esophoric fixation disparity at close focus.52 Further studies beyond 12 months should be carried out which could validate their findings. Other studies reviewed55,56,57 show that dual focus CLs or SMCLs are more effective in controlling myopia progression than spectacles (including PALs) possibly because CLs are more likely worn throughout the day than spectacles, thus improving compliance. The addition in SMCLs is also constant in all angles of gaze.52 However, recent research involving the DIMS® lens indicates reduced myopic progression by 52% compared to SV spectacle lenses. The low dropout rate and improvement in wearing time of the DIMS® spectacle lens made it a more attractive option than the DISC® CL. The implication of this in clinical practice is that the spectacle form of control with peripheral defocus lenses could offer a better adaptability than their CL counterpart when it becomes commercially available. As the DIMS® lens is a new innovation, further clinical trials involving peripheral defocus spectacle lenses (PDSLs) in other ethnic groups and high myopes (from −5.00 D) would be needed to ascertain its effectiveness in reducing myopia progression.
For myopic subjects with astigmatism, reports indicate that the presence of astigmatism could increase the chances of myopic progression.75,76 Internal astigmatism (IA) has been identified as a stimulus factor for AL growth.76 A study77 indicates that toric Ortho-K can reduce corneal astigmatism by 48.1% (from 2.35 D to 1.22 D), whereas spherical Ortho-K resulted in a 10.5% decrease (2.29 D – 2.05 D). In moderate-to-high astigmatism, toric Ortho-K also gave better myopia control effect of 55.6% when compared to spherical Ortho-K. A 10-year follow-up study78 revealed that the increase in AL was more in younger children with a high baseline myopia and that Ortho-K control stabilises after seven years, although a decelerating effect was reported in AL elongation in the early years.78 An important feature of Ortho-K is that it can create large optical treatment effect in moderate-to-high myopia unlike other forms of optical treatment. Orthokeratology is also comparable to low-dose atropine in reducing myopia progression.63,79 However, Ortho-K has its disadvantages that include the risk of infectious keratitis, the risk of corneal damage, wear discomfort and high cost.78
In all the optical methods reviewed, PALs and bifocals appear to be the least effective. Dual focus CL, novel peripheral defocus lenses (PDLs) and Ortho-K give moderate myopia control and seemed to be the most effective optical methods of myopia control (Figure 1 and Table 2). The PDLs showed promise for the future. Reports33,80 indicate higher prevalence and faster progression of myopia in Asians as compared to Europeans. As most of the studies reviewed on myopia control involve Chinese children as displayed in Table 2, there is a need for more research duplicating some of the studies on individual interventions as well as comparing different ethnicities. Before concluding that ethnic differences exist, the study design needs to control for the lifestyle differences that exist between ethnicities in different locations.
FIGURE 1: Bar chart showing the average reduction rates (%) of optical methods of myopia control. Under-correction was not included as the studies reviewed indicate an increase in myopic progression. Studies by Lam et al. (2019) (DIMS®) and Chen et al. (2013) (orthokeratology) indicate the best control (52%), while progressive addition lenses and bifocal lenses indicate the weakest (13% and 20%, respectively).
TABLE 2: Effect of optical methods on myopia progression.
A combination of methods (such as partial Ortho-K and full correction with SVLs) could be more effective in reducing myopic progression. The baseline myopia for most of the studies reviewed ranged from −1.00 D to −5.00 D, higher magnitude myopia tends to progress faster than lower magnitude. Control measures should be implemented from −1 D and the phoria status has also to be considered as lower power (addition) is needed for less esophoric children. The near addition for PALs should be tailored to meet the individual needs of the patient. Clinicians should consider the use of peripheral defocus lenses particularly the spectacle form (52% effective and easier to wear than CLs) for myopia control as commercial availability becomes more accessible.
Myopia control measures can be easily incorporated into spectacles and CLs because they are common forms of correction. This underlines the importance of this review. Randomised controlled trials are the most commonly used study designs for myopia control. Peripheral defocus lens (either of concentric rings or progressive in nature) and multifocal CL designs based on myopic defocus theory offer the most effective myopia control. Orthokeratology is equally effective but future designs should consider ways of minimising risks of complications with lens wear. For the newer methods (PDCLs and PDSLs), studies that involve PDSLs reported lower dropout rates and easier adaptability than PDCLs. This implies that the PDSLs could be more useful and feasible in clinical practice as a form of myopia control. Under-correction is not considered an option based on available evidence. More studies would be needed to better understand how under-corrected myopic eyes tend to progress faster, whereas myopic eyes without correction tend to progress slower. A holistic approach and combination of methods may offer the best form of myopia control in the 21st century considering the increase in near work activities and use of digital devices among the most vulnerable groups.
K.N. in addition to being a researcher with African Vision Research Institute (AVRI) at the University of KwaZulu-Natal is employed by Essilor (which sells optical lenses) as Vice President (VP) of Inclusive Business, Philanthropy and Social Impact.
T.R.A. was responsible for writing the article and K.S.N. and S.O.W. were responsible for the review and editing of the article.
This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.
Data sharing is not applicable to this study as no new data were created or analysed in this study.
The views expressed in this article are those of the authors and not the official position of the affiliated institutions.
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Chamsa's traditional sugar paste now available in a flow pack that requires no prior heating!
Open the package promptly, and remove Caramel sugar paste.
Rub the paste till it becomes silky and adhesive.
Apply a small amount of sugar-paste on a small surface of the skin to first test sensitivity.
Apply the paste downwards in the direction of the hair growth.
Remove the paste quickly in the opposite direction of hair growth.
For better result: re-massage the paste in case of repeated application on other parts to be depilated.


This was the first Free Comic Book Day that I felt like I got much accomplished rather than just hitting my LCS for some great books and signatures. As always, I spent it down at Tony's Kingdom of Comics and Collectibles... and he outdid himself this year!
It helped that the Radio Shack that was located next door to Tony's shop had gone out of business, and he was able to utilize that space for several artists like Shawn Cruz & AnnMare Grove from Corrosive Comics and Ryan Alonzo of Alonzo Art... all 3 of whom are contributing artists to Comic Book Covers 4 Cancer. Also, Tony was able to display a number of different silent auction packages which included so many items donated by either Tony or local businesses as well as Cherry City Comic Con, Northwest Comic Fest and Rose City Comic Con!
As always, Tony also had an area for food donations to the Keizer Community Food Bank and the proceeds for the silent auctions are going to the Shriners Hospitals for Children. There was also an area setup for people to take their pictures with members of Star Wars Oregon and the Portland Superheroes Coalition.
Of course, the one thing that really draws people into any Free Comic Book Day events are the free comic books. Tony had that covered in spades, including a donation of trades from his friend at Things From Another World.
On top of all this, Tony also had comic book artists Ron Randall and Gary Martin in store to sign. I was fortunate enough to pick-up a copy of Gary's book "The Art of Comic Book Inking" which I have wanted for years and we're going to try and connect to have Gary on-board as a contributing artist to Comic Book Covers 4 Cancer as well.
Casey Ocupe also was supporting FCBD as well as making sure to spread the word about this years Northwest Comic Fest in August. He was selling tickets to Comic Fest as well as his signature masks.
On the Wednesday preceding this years event, Tony contacted me an suggested that I could setup a table to help raise money for Comic Book Covers 4 Cancer. Even though I had other plans for the day, I made sure that I could take advantage of this great opportunity to help continue to spread the word about CBC4C and hopefully raise some money to get us ready for our table at NW Comic Fest in August.
When I was leaving the store, I wanted to make sure to touch base with Tony to let him know that I would try to make it back before the store closed to pick-up the brochures, business cards and donation jar. He informed me that his intentions were to keep the donation jar in the store in hopes of being able to generate additional resources for our cause.
I'm not too proud to say that Tony's gesture nearly brought tears to my eyes. Tony has been the greatest supporter to our cause and I only hope that I can measure-up to what he has done for CBC4C and the entire community.
For the time that I was able to spend down at Tony's this FCBD, I could feel the positive energy from everyone. I saw a lot of familiar faces alongside new faces. It felt good to be a part of it all and I can only imagine what will be in store for next years event. I'm already counting the days.


Behind the rolling hills and stunning countryside of Dumfries and Galloway is a problem that may surprise you. Homelessness might be an all too common sight in our towns and cities, but it exists in more rural areas too. One charity describes it as a 'hidden' issue because it often can't be seen.
Dawn Rawlinson was 51 when she found herself facing homelessness for the first time in her life. The house she lived in was being sold by a family member to raise funds. She works but couldn't afford expensive private accommodation and felt she had nowhere to turn.
"The situation was very daunting, very scary, thinking where was I going? Where was I going to end up next?"
Luckily, Dawn's daughters helped her find some assistance. The Charity Shelter Scotland found her a flat and are helping her navigate her way through bills and expenses to ensure she keeps her accommodation.
Dawn is proof homelessness can happen to anyone. Vicky Long is a housing support worker, she drives all over the Stewarty area of Dumfries and Galloway providing practical and emotional support.
"It definitely is a hidden problem. The public perception is street homeless, people sleeping in cardboard boxes that sort of thing, whereas in this area we get a lot of people made homeless who stay with friends, who are sofa-surfing - staying one of two nights then moving on - staying with family, families moving in with grandparents, so they've got the issue of overcrowding."
Living in rural areas can have other issues. A lack of social housing, isolation and problems accessing technology can make an already difficult situation even worse.
Dumfries and Galloway Council and the Scottish Government say they are addressing the lack of social housing in more rural area and building hundreds of new homes.
If you find yourself homeless, or facing homelessness in Dumfries and Galloway, the first step is to ring the council who can refer you to a charity or organisation in your area. The number is 030 33 33 3000.


Step back in time and walk in the footsteps of Charles Dickens!
See where he wrote, where he dined, and where he and his wife Catherine entertained their many guests. Immerse yourself in the sights and sounds of his family home.
'My house in town', as Dickens referred to 48 Doughty Street, was an important place in the writer's life: within these walls his eldest two daughters were born, his sister-in-law Mary died aged 17 and some of his best-loved novels were written, including Oliver Twist. It was in this house that he achieved lasting celebrity and universal recognition as one of the world's greatest storytellers.
This is the only remaining house of Charles Dickens in London and the one in which he began married life, became established as a writer, and rose rapidly to international fame. The Museum houses the world's finest and most comprehensive collection of material relating to Charles Dickens with over 100,000 items including furniture, personal effects, paintings, prints, photographs, letters, manuscripts, and rare editions. A rolling programme of special exhibitions enhances and complements the Museum's permanent displays.
The Charles Dickens Museum is part of the Museum Mile: 13 of London's most extraordinary museums and galleries stretching from King's Cross to the River Thames.


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Fariq Abdul Hamid, Zaharie Ahmad Shah Pilots on Missing MH370 Flight: Who Are They?
March 11, 2014 Updated: June 28, 2015
Zaharie Ahmad Shah was the pilot on Malaysia Airlines flight MH370, which went missing; Fariq Abdul Hamid was the co-pilot.
Who are these two men?
Shah joined the airline in 1981 and has 18,365 hours of flight experience. He's a 53-year-old Malaysian resident.
He was described as an aviation geek by a Malaysian Airlines co-pilot who flew with him in the past.
"He was an aviation tech geek. You could ask him anything and he would help you. That is the kind of guy he is," the pilot told Reuters. Shah had a Boeing 777 simulator at his home in a suburb on the outskirts of Kuala Lumpur, with easy access to the airport. The simulator, which Shah showed off in photos posted on Facebook, had three computer monitors among other equipment.
"We used to tease him. We would ask him, why are you bringing your work home," said a pilot who knew Shah for 20 years.
Shah also collects remote-controlled, miniature aircraft, a sign of his passion for aviation.
Malaysia's Department of Civil Aviation certified Shah to conduct simulator tests for pilots, several officials from the airline said. They said that he couldn't have been behind whatever happened to the plane.
"He knew everything about the Boeing 777. Something significant would have had to happen for Zaharie and the plane to go missing. It would have to be total electrical failure," said another Malaysia Airlines pilot who knew Shah.
The theory of of a dive into the sea from a high altitude was dispelled from a former Malaysia Airlines pilot that now works for another airline. "The Boeing 777 doesn't just stall like that," he said. "It is one of the safest planes out there. It doesn't just fall out of the sky like that."
AP Photo/Kyodo News
Shah may be Muslim, as his niece Dee Hassan said via Twitter that she was praying to God, asking him to protect her uncle. One of her tweets was a retweet of a relative who referred to Allah.
He is remembered as an active community member who cooked dishes and brought them to neighborhood gatherings, reported the New Straits Times.
"You're lucky if you have a neighbor like him," said one of his neighbors, Rahim Zainun.
There is 120 houses in Laman Seri, the neighborhood, and everyone was close knit.
"I have known him since 2008 and we are good friends. Whenever there is a gathering, he always helps out with the food and preparation," he said.
"He often brings food that he cooked himself like spaghetti and rice noodles to gatherings. He always makes sure that his wife, kids or somebody will send at least a cake if he cannot attend a kenduri when he is on duty. That is how good a neighbor he is."
Another neighbor said that he cried when he learned what happened.
Hamid is also a Malaysian.
The 27-year-old joined the airline in 2007. He has 2,763 hours of flight experience.
Fariq is the the youngest son of Selangor Public Works Department deputy director Abdul Hamid Mad Daud, reported the New Straits Times.
Not much is known about Hamid with the focus more on Zaharie, but a shocking revelation emerged this week as a tourist recounted how she and a teenage girlfriend spent an entire flight in the cockpit with Hamid and another pilot in 2011.
"Throughout the entire flight they were talking to us and they were actually smoking throughout the flight which I don't think they're allowed to do," Jonti Roos told Channel 9.
Roos, a South African who is traveling around Australia, posed for pictures with her friend Jaan Maree and the two pilots.
Jonti Roos, in pink, with Fariq Hamid, far right, in a file photo. (Channel 9)
Roos insisted that the pilots were in control. ""I did feel safe. I don't think there was one instance where I felt threatened or I felt that they didn't know what they were doing," she said.
"The whole time I felt they were very friendly. I felt they were very competent in what they were doing. We wished they would stop smoking because it is such a confined space. But you can't exactly tell a pilot to stop smoking."
Malaysia Airlines investigators are looking into the account.
Follow Zachary on Twitter: @zackstieber
227 Dead After Monsoon Floods Devastate South Asia
By Wire Service Content
At least 227 people have died since flash floods ravaged swathes of South Asia over the weekend, officials said on Thursday, July 18.
Over 20 Feared Dead or Presumed Dead in Arson at Japan Studio
TOKYO—Over 20 people were feared dead and dozens more either unconscious, hurt, or missing in a suspected case of arson at an animation studio in the Japanese ...
MH370 Investigators Say 'Mystery' 200-Pound Load Was Added to Cargo Flight List After Take-Off
By Isabel van Brugen
A "mysterious 200-pound load" was added to the flight list of MH370 after take-off, according to an engineer whose wife and two children were on board the ...

redpajama_set_name: RedPajamaCommonCrawl


Thursday morning I worked at the library–I enjoy the time spent with the books. The Cowboy has been on the roof most of this week. He did meet with the electric company people–we are going to eliminate a low hanging loop of electrical wire which runs from the last electric pole to the house by burying that wire. And it takes an act of congress and money!! It just makes sense–we don't want one of our RVing friends to catch that wire or catch the wire with the backhoe–so underground it goes.
Friday evening we were invited to the home of Dan and Louanne–we met them at the VFW hall a few weeks ago. They invited other friends and we met more people–it was a fun evening!
Today I tackled a chore I've been avoiding–I ripped the drywall from a major part of the ceiling in the main house kitchen/hall/bath area. Nasty, stinky, dusty, sweaty work–I wore a respirator mask–and I'm glad to have that major chore behind me. There is still more to do–we have walls to remove and more ceiling drywall in a couple closets but I made a huge dent today. Whew!
Tonight we are off to try the rib dinner at the VFW hall. Update–the ribs were delicious!
I wasn't getting out there in the wind/rain to take photos–:) :)–that's my excuse and I'm sticking to it!
I'm going to be exhauated by the time the main house is finished! This project is huge but I'm hanging with you!!! Haha! You'll be glad to get back to Montana and rest. But I don't believe either of you rest much:) Boy the wind was wicked this afternoon. Please be careful on that roof, Michael!!
It was a wicked wind and then the rain–wind is so bad the Cowboy's hat won't stay put!
Definitely time to come in when the hat goes!!
We didn't get one drop of rain but the wind was fierce. About blew the Cowboy shooters off the range! We had a group of 13 that went to the Horseshoe in Benson for breakfast and dust 😈's was coming at us across the roads. It was exciting!
Just a little rain but lots and lots of wind! I would bet parts of the interstate were closed by all that dust.
We remember the winds from last spring–at least we aren't seeing 50mph gusts which is happening today in Montana!!!


text:
Q: Calculation using javascript in drupal 6 Hi everyone i am new to drupal i am developing a module where i need a calculation using java scrip or jquery but i dont no how to implement .js files or how to write a javascript in drupal can anyone pls provide me a releated links or any help on this thanks in advance.

A: You can add javascript to your module using drupal_add_js and for adding to Page template use normal way (using script tag)
Remember that javascript client side script and preferred for preprocessing like form validation
EDIT:
tutorial ,
samples

redpajama_set_name: RedPajamaStackExchange


text:
Q: [__NSCFNumber length]: unrecognized selector sent to instance 0x6d21350 What could this error mean?
[__NSCFNumber length]: unrecognized selector sent to instance 0x6d21350

Here is my code:
    NSString *urlString = @"http://api.twitter.com/1/statuses/update.json";
    NSURL *url = [NSURL URLWithString:urlString];

    NSMutableDictionary *params = [[NSMutableDictionary alloc] init];
    [params setObject:status forKey:@"status"];
    [params setObject:replyToID forKey:@"in_reply_to_status_id"];
    [params setObject:@"1" forKey:@"include_entities"];

    // Build the request with our parameter
    TWRequest *request = [[TWRequest alloc] initWithURL:url parameters:params requestMethod:TWRequestMethodPOST];

    // Attach the account object to this request
    [request setAccount:twitterAccount];

    [request performRequestWithHandler:^(NSData *responseData, NSHTTPURLResponse *urlResponse, NSError *error) {
        if (!responseData) {
            // inspect the contents of error
            NSLog(@"%@", [error localizedDescription]);

            self.alert = [[UIAlertView alloc] initWithTitle:@"HTTP error" message:@"I could not connect to the Twitter API." delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil];
            [self.alert show];

            [self.replyDelegate replyRequestSuccessful:NO];
        }
        else {
            /*NSString *responseDataAsString = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
             NSLog(responseDataAsString);*/

            NSError *error;
            NSArray *replyResponse = [NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableLeaves error:&error];

            if (!replyResponse) {
                NSLog(@"%@", [error localizedDescription]);

                self.alert = [[UIAlertView alloc] initWithTitle:@"JSON error" message:@"I could not parse the JSON response from the Twitter API." delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil];
                [self.alert show];

                [self.replyDelegate replyRequestSuccessful:NO];
            }
            else {
                [self.replyDelegate replyRequestSuccessful:YES];
            }
        }
    }];

I tried debuggin, and it dies once it enters the performRequestWithHandler. It goes the else block and dies with the error above.

A: It means that you are passing an NSNumber where the called code expects an NSString or some other object that has a length method. You can tell Xcode to break on exceptions so that you see where exactly the length method gets called.

A: Specifically this line of code:
[params setObject:replyToID forKey:@"in_reply_to_status_id"];

the replyToID is not a String or has a method length. If you don't have this, or if you convert the replyToID to a String before setting it in params it should work.


Weight gain, heredity, pregnancy, hormonal changes, trauma and prolonged sitting or standing are all sources that contribute to the development of larger varicose veins as well as smaller spider veins.
If you are tired of dealing with spider veins, schedule an appointment with one our skin specialists at Cassileth Skin Care in Beverly Hills and find out how Sclerotherapy may be just what you need.
What is Sclerotherapy used for?
Sclerotherapy is a procedure where tiny injections are given to erase small varicose veins and "spider veins". This highly effective spider vein treatment is available through our skin care experts at Cassileth Skin Care in Beverly Hills.
Erase small varicose veins and "spider veins"
Sclerotherapy involves tiny injections of a sclerosing agent directly into the spider or varicose vein. The solution causes the blood vessel to collapse and clot, it is then absorbed by the body and then disappears.
What happens during the Sclerotherapy treatment?
During Sclerotherapy treatment in our Beverly Hills med spa, we use the tiniest needle made to comfortably inject the veins - this can take from 15 minutes to an hour, depending on the size and number of veins to be injected.
After receiving Sclerotherapy in Beverly Hills, walking is encouraged and you can resume your daily activities. You will wear support hose to compress the treated vessels for one week after treatment to keep blood flow out of the treated veins.
Studies have shown that as many as 50%-80% of injected veins disappear with each session of Sclerotherapy. Normally, spider veins respond in 3-6 weeks, and larger veins respond in 3-4 months. If the veins respond to the treatment, they will not reappear. You may need to return to address new veins.
Common side effects can include itching for 1-2 days after the procedure. You can take an over the counter anti-histamine such as Claritin or Allegra. The injection site may become raised and red, but should disappear within a few days. Bruising can occur around the injection site and last a few days to several weeks.
Do not use lotion near the injection site before the procedure.
Avoid anti-inflammatory drugs (such as Aspirin, Ibuprofen, Advil, Motrin and Nuprin) for 48-72 hours before Sclerotherapy. Tylenol can be taken if necessary.
Wear your compression hose for one week. Avoid aspirin, ibuprofen, or other anti-inflammatory drugs for at least 48 hours. Tylenol can be taken if necessary.
Avoid hot baths, whirlpools, saunas, hot compresses and direct exposure to sunlight for 48 hours after treatment. Showers are okay, but use cooler water. You can wash the injection site with mild soap and lukewarm water.
To find out more about receiving among the best Sclerotherapy Beverly Hills has to offer, call our office today and start your journey to the beautiful body you deserve!


text:
In-depth news coverage of the Greater Boston Area.
Details Released on Vegas Shooter's Boston Google Searches
By Marc Fortier	• Published January 19, 2018 • Updated on January 19, 2018 at 4:42 pm
Information released Friday revealed that the gunman who opened fire on concertgoers in Las Vegas last fall, killing 58 and injuring hundreds of others, researched numerous Boston locations online in the months before the massacre.
Immediately after the Vegas shooting, it was revealed that Stephen Paddock had researched Fenway Park and the Boston Center for the Arts.
Investigators in Las Vegas released information Friday about Paddock's Google searches as they revealed the motive behind the worst mass shooting in modern U.S. history remains a mystery.
Roxbury 7 hours ago
Paddock's queries included Google Map searches for several Boston locations, including Fenway Park, the Royal Rooters Club, Blandford Street MBTA Station, Boston University's School of Business, Hotel Buckminster, the Boston Arts Academy and the official Boston Red Sox team store.
The gunman, whom investigators determined was working alone, had searched for the locations along with several search terms - including "summer concerts 2017," "open air concert venues," biggest open air concert venues in USA" - in mid-May of last year on an Internet Explorer private browser.
There is no evidence that Paddock ever traveled to Boston.
Investigators also revealed Friday that Paddock had Googled locations in Venice and Santa Monica, California around the same time he was researching landmarks in Boston.
In mid-September, Paddock began searching "swat weapons," "SWAT Las Vegas," "ballistic" and "do police use explosives", according to the Clark County Sheriff's Department.
Late in the evening on Oct. 1, Paddock opened fire from the 32nd floor of the Mandalay Bay hotel into a crowd of 22,000 attending a country music festival below. Paddock, a 64-year-old retired accountant and multimillionaire real estate investor, killed himself with a gunshot to the mouth before police reached him.
Authorities have said they found no link to international terrorism. They believe Paddock meticulously prepared his plan to fire assault-style weapons from the Mandalay Bay into the crowd at the Route 91 Harvest Festival.
Paddock fired more than 1,100 bullets, mostly from two windows, police have said. That includes about 200 shots fired through his hotel room door into a hallway where an unarmed hotel security guard was wounded in the leg and a maintenance engineer took cover.
United StatesNBCCaliforniaMarc FortierLas Vegas


text:
8-hour total weight average (TWA) permissible exposure limit (PEL).
OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.
Mr. Mark Nicas
140 Warren Hall
Berkeley, California 94720-7360
Dear Mr. Nicas:
This is in response to your letter of July 7, addressed to Mr. Joseph A. Dear, Assistant Secretary for the Occupational Safety and Health Administration (OSHA), requesting an interpretation on 8-hour total weight average (TWA) permissible exposure limit (PEL) as defined in 29 CFR 1910.1000 and in other substance-specific health standards.
The 8-hour TWA PEL is defined in the Federal Register, Vol. 57, No. 114, June 12 1992, pps 26539, 26556, 26572, 26573 and 26590 as follows:
"TWA is the employee's average airborne exposure in any 8-hour work shift of a 40-hour work week which shall not be exceeded."
The 8-hour TWA PEL is the level of exposure established as the highest level of exposure an employee may be exposed to without incurring the risk of adverse health effects. This should not be confused with short term exposure limits (STELs) or peaks. Therefore, your interpretation #1 comes closest to OSHA's definition of an 8-hour TWA PEL. OSHA would be justified in issuing a citation when personal air sampling indicates employee exposure to be in excess of the PEL on the day sampled.
It is well established by the industrial hygiene profession that a workplace survey should be conducted in a facility to determine the potential for exposure(s) in excess of established exposure levels such as the PEL and TLV's. This survey must include job tasks and the potential created for the exposure by these tasks over all operational shifts as well as the potential for increased exposure(s) as a result of production/work demands. The industrial hygiene survey will allow the employer to establish which shift(s), process(es), etc. need to be sampled in order to acquire a representative sampling of employee exposure. Good industrial hygiene practice dictates that significant changes in the work process would call for additional personal air monitoring thus acquiring revised data which will be representative of employee exposure(s).
As you may be aware, the State of California administers its own occupational safety and health program under a plan approved and monitored by Federal OSHA. Therefore, employers in California must comply with State occupational safety and health requirements. States are required to adopt and enforce occupational safety and health standards at least as effective as those promulgated by Federal OSHA and may be more stringent. If you would like further information regarding California occupational safety and health requirements, you may contact the California Department of Industrial Relations directly at the following address:
[Chuck Cake, Acting Director
California Department of Industrial Relations
455 Golden Gate Avenue
Telephone: (415) 703-5070]
We hope this information is helpful. If you have any further questions, please contact the [Office of Health Enforcement at (202) 693-2109].
Joseph A. Dear
(Corrections 5/23/2003) Please see the May 13, 1999 letter to Mr. Douglas S. Ellmann, Esq. for additional clarification on this issue.
Joe Dear, Assistant Secretary of Labor
Room S2316
200 Constitution Avenue, N.W.
I am writing to secure your official interpretation of an OSHA health standard, namely, the 8-hour TWA permissible exposure limit (PEL) as defined in 29 CFR 1910.1000 and in other substance-specific health standards. Let me provide a background for this request.
Many people believe that an 8-hr TWA PEL is an 8-hr TWA value not to be exceeded on any workday, in other words, the PEL is an absolute limit on the 8-hr TWA value. According to this interpretation of the PEL as an absolute limit, if the 8-hr TWA value exceeded the PEL value on, say, 1 in 1000 workdays, the employer would be deemed out of compliance and OSHA would be justified in issuing a citation for over-exposure. Also according to this interpretation, it would be true that if the 8-hr TWA equaled the PEL value on every workday, the employer would be deemed in compliance and OSHA would not be justified in issuing a citation. I call this Interpretation #1.
In contrast, some people believe that an 8-hr TWA PEL is an 8-hr TWA value that may not be exceeded on the great majority of workdays, say, 95%, although it may be exceeded on the remainder. According to this interpretation of the PEL as a permissible percent exceedance, if the 8-hr TWA value exceeded the PEL value on, say, 100 in 1000 workdays (10%), the employer would be deemed out of compliance and OSHA would be justified in issuing a citation for over-exposure. But if the 8-hr TWA value exceeded the PEL value on only 50 in 1000 workdays (5%), the employer would be deemed in compliance and OSHA would not be justified in issuing a citation. I call this Interpretation #2.
Finally, other people believe that an 8-hr TWA PEL is a permissible long-term mean value, in other words, the permissible mean of all the 8-hr TWA values that may occur. According to this interpretation of the PEL as a permissible mean, if the 8-hr TWA value exceeded the PEL value on, say, 300 in 1000 workdays (30%), but the mean of these 1000 8-hr TWA values was below the PEL value, the employer would be deemed in compliance and OSHA would not be justified in issuing a citation for over-exposure. On the other hand, if the mean of these 1000 8-hr TWA values exceeded the PEL value, the employer would be deemed out of compliance and OSHA would be justified in issuing a citation. I call this Interpretation #3.
Given this preface, my question is the following: Which of these three interpretations is OSHA's official interpretation of the 8-hr TWA PEL, or does OSHA have a different official interpretation? For example, perhaps it's Interpretation #2, but with the permissible percent exceedance being only 1% of workdays.
My question is not academic, because its answer broadly impacts industrial hygiene sampling strategies and the interpretation of exposure data with respect to compliance with the OSHA PEL's. For example, if the PEL is an absolute limit on the 8-hr TWA value (Interpretation #1) and an employer wants to determine compliance with the PEL, then the employer should monitor on the "worst-case" day, that is, the day when the very highest exposure is expected to occur. Further, if Interpretation#1 is correct, then the employer should not monitor on a randomly selected day nor on a "representative" (i.e., average) day, because the highest exposure is not likely to occur on a random day or a "representative" day. On the other hand, if the PEL is a permissible long-term mean value (Interpretation #3) and an employer wants to determine compliance with the PEL, then the employer should monitor on a "representative" day, or perhaps on several randomly selected days (so that the mean may be statistically estimated), but should not monitor on the "worst-case" day because the 8-hr TWA value on the "worst-case" day will almost always be greater than the long-term mean value.
Let me say that I find the language and rationale in many OSHA substance-specific standards inconsistent with respect to this question. For example, in the benzene standard (29 CFR 1910. 1018), the 8-hr TWA PEL was based on risk assessments that related cumulative dose to lifetime cancer risk, such that exposure at the PEL value every day over a working lifetime would result in a certain permissible increment of cancer risk. Because the cumulative dose is equal to the product of the long-term mean exposure level and exposure duration, it would seem logical that the PEL be viewed as a permissible long-term mean value (Interpretation #3). Further, under paragraph (e) Exposure Monitoring, the standard states that "representative 8-hr TWA employee exposures shall be determined..." Again, the term "representative" implies a determination of the long-term mean 8-hr TWA exposure value. However, the benzene standard also incorporates the "action level" decision logic, where the action level is set at one-half the 8-hr TWA PEL value. The provenance of this action level is a 1975 NIOSH analysis which explicitly assumed that it was permissible for the 8-hr TWA value to exceed the PEL value on 5% of all workdays (Interpretation #2). Finally, based on my own experience as an OSHA compliance officer, I know that finding an 8-hr TWA benzene exposure above the PEL value on just one inspection day warrants issuing a citation for over-exposure (Interpretation #1).
In closing, your official interpretation would clear up a good deal of confusion among industrial hygienists. Further, it could be referenced in the next edition of the AIHA monograph A Strategy for Occupational Exposure Assessment which is currently in development. I greatly appreciate your responding at your earliest convenience.
Mark Nicas, PhD, MPH, CIH
Research Industrial Hygienist
Member, AIHA Exposure Assessment Strategies Committee


text:
List of Gods : "Ares" - 81 records
"Agares" Christian	 One of the fallen angels, of the order of the virtues who governs thirty-one legions, appears riding a crocodile and carrying a sparrowhawk.
Demon name
"Agares / Aguares" Greek	 Agares aka Aguares devil. Wierius' hierarchy states Agares is the demon of courage Grand Duke of the eastern regions of Hell, commander of thirty-one legions.
"Agraulos" Greek	 A daughter of Actaeus, the first king of Athens. By her husband, Cecrops, she became the mother of Erysichthon, Agraulos, Herse, and Pandrosos. 2. A daughter of Cecrops and Agraulos, and mother of Alcippe by Ares.
"Alcippe" Greek	 Daughter of Ares and Agraulos, the daughter of Cecrops. Halirrhothius, the son of Poseidon, intended to violate her, but was surprised by Ares, and killed, for which Poseidon bore a grudge against Ares. (Apollodorus iii.)
"Alruna-wife" German	 The Alrunes were the lares or penates of the ancient Romans. An Alruna-wife was the household goddess of a German family. An Alruna-maiden is a household maiden goddess.
"Althaea" Greek	 A daughter of the Aetolian king Thestius and Eurythemis, and sister of Lecla, Hypermnestra, Iphiclus, Euippus, etc. She was married to Oeneus, king of Calydon, by whom she became the mother of Troxeus, Thyreus, Clymenus, and Meleager, and of two daughters, Gorge and Deianeira. (Apollodorus i) Apollodorus states, that according to some, Meleager was regarded as the fruit of her intercourse with Ares, and that she was mother of Deianeira by Dionysus.
"Amoghapasa" Buddhist	 Brings believers hope and tranquility. Amoghapasa has four pairs of arms. One pair is held with palms together in a prayerful attitude. Some are raised, others are held slightly away from the body. The hands may be in symbolic positions called mudra or may hold symbolic articles like a lotus blossom, symbol of compåśśion; a monk's staff; a whisk representing the brushing away of earthly cares; and the låśśo. Buddhist
"Anceta" Kamos Moab / Jordan	 The chief god that when Hellenized became equated with Ares
"Anteros" Greek	 (Anterôs) was the son of Ares and Aphrodite, given to his brother Eros, who was lonely, as a playmate. He is the personification of unrequited love and punisher of those who scorn love, and is depicted as similar to Eros in every way, but with long hair and butterfly wings. The term was also used for the love which arises in the beloved boy in a pederastic relationship.
"Anteros" Greek / Etruscan	 The son of Ares and Aphrodite in Greek mythology, given to his brother Eros, who was lonely, as a playmate. He is the personification of unrequited love and punisher of those who scorn love, and is depicted as similar to Eros in every way, but with long hair and butterfly wings. Greek / Etruscan
"Aray" Pre - Christian Armenian	 war god. Probably derived locally from the Greek ARES. Some traditions suggests that he was also a dying-andrising god....
"Ares" Greek	 God of storms and war. Ares is a lesser known member of the Olympic pantheon of great gods, the son of ZEUS and HERA, who allegedly lived in Thrace. As a warrior god he is contrasted with the more prominent and successful goddess ATHENA who fought and vanquished him in a war between the gods. Although Athena stands for victory in battle through glory and honor, Ares epitomizes the evil and more brutal aspects of warfare. In the eyes of Zeus he is "the most hateful of gods."
"Ares" Greek	 The god of war and one of the great Olympian gods of the Greeks. He is represented as the son of Zeus and Hera. A later tradition, according to which Hera conceived Ares by touching a certain flower, appears to be an imitation of the legend about the birth of Hephaestus, and is related by Ovid.
"Ares Lusitani" Lusitanian	 The God of horses. Lusitanian
"Areskoui" Haudenosaunee	 Areskoui The Great spirit as Patron of the hunt and of war. Haudenosaunee
"Arestor" Greek	 The father of Argus Panoptes, the guardian of Io, who is therefore called Arestorides. Greek
Hero name
"Argus" Greek	 A beast and son of Arestor with a hundred eyes of which he could only close two at a time. He was placed by Juno to guard Io, whom Jupiter had changed into a heifer. But Mercury, who was sent to carry her off, managed to surprise and kill Argus whereupon Juno transfered his eyes to the tail of a peaçõçk, her favourite bird. In Greek mythology, Argus was the name of the builder of the Argo, the ship that carried the hero Jason in his quest for the Golden Fleece.
"Auchimalgen" Chile	 moon goddess, wife of the Sun. Only Auchimalgen cares anything for the human race, all the rest of the gods being utterly malevolent. Auchimalgen wards off evil spirits and turns red when some important person is about to die. Chile
Nymph name
"Azan" Greece	 A son of Ares and the nymph Erato, was the brother of Apheidas and Elatus, and father of Cleitor. The part of Arcadia which he received from his father was called, after him, Azania. After his death, funeral games, which were believed to have been the first in Greece, were celebrated in his honour.
Ghost name
"Bhut" India	 A type of evil spirit. It is especially the evil ghost of a man who has died due to execution, accident, or suicide. People protect themselves by lying on the ground, because the bhutas never rest on earth. In the Bhagvad Gita, Krishna the Avatar declares that the humans who worship bhutas become bhutas themselves. India


text:
A huge congratulations to our 10 finalists in our inaugural EarthTech Challenge. On the 20th February 2020, our finalists will be gathering at the EarthTech Summit on Makepeace Island in Noosa, Australia to receive further mentoring from our team of experts in Social Enterprise, Science, Finance and Impact. On Saturday 22nd, the teams will then present their final pitch in front of a panel of judges to decide who will win the EarthTech Challenge for 2020. Learn more about the EarthTech Summit below.
Also, make sure to follow us on Facebook, Twitter and Instagram – or join the tribe to receive updates via our email newsletter.
Safewheel is an affordable emergency medical service provider to the rural people of Bangladesh. With our environment friendly mini electric tricycle ambulance, we provide affordable ambulance and doorstep medical service to villagers living under 5 USD PPP (Purchasing Power Parity) per day. Our response time is 300% faster, and our service charge is 50% cheaper than all the existing ambulances operating in rural areas of Bangladesh.
The EarthTech Summit
Our finalists are now making their way to the EarthTech Summit at Makepeace Island in Noosa, Richard Branson's home in Australia. We are looking forward to meeting our finalists and hosting them over three action packed days!


text:
WALK THE MOON RELEASE MUSIC VIDEO FOR "TIGER TEETH" TODAY—CLICK HERE TO WATCH
WINTER 2019 HEADLINING TOUR DATES ANNOUNCED
TICKETS ON SALE NOW
(October 25, 2018)—Today, critically acclaimed band WALK THE MOON release the music video for "Tiger Teeth," which was directed by Dusty Kessler & Eric Maldin (Click HERE to watch). The track is featured on the band's most recent album What If Nothing, which is available at all digital retail providers via RCA Records.
WALK THE MOON'S Nicholas Petricca says about the video: ""Tiger Teeth' has been known to WALK THE MOON fans since years before it was recorded, when it only existed as a rare live video taken on someone's phone that was circulating the internet. After countless fan requests for the song to be released, it finally made it onto an album last November with 'What If Nothing.' We knew we had to create something special for the fans who've been so loyal to the song for so long. So while on tour in Asia, we flew a skeleton crew out to meet us in between gigs in Japan. The music video takes place on location in the streets of Tokyo and the nature of Kamakura, which we think is a perfect match for the melancholy of 'Tiger Teeth.'"
Additionally, WALK THE MOON has announced their headlining Winter 2019 Tour, which will be making a number of stops in many cities across North America. The tour will kick off with a headlining radio show in Chicago, then two stops in Louisville, and will also hit cities including Buffalo, Montreal, and Baltimore. Tickets for the tour are on-sale now and can be purchased here. See full list of tour dates below.
SAT 12/1 101 WKQX The Nights We Stole Christmas Chicago, IL
WED 1/23 Mercury Ballroom Louisville, KY
THU 1/24 Mercury Ballroom Louisville, KY
FRI 1/25 20 Monroe Live Grand Rapids, MI
SAT 1/26 UB Center For The Arts Buffalo, NY
MON 1/28 State Theater Ithaca, NY
TUE 1/29 Corona Theater Montreal, QC
THU 1/31 State Theater Portland, ME
FRI 2/1 The Strand Providence, RI
SAT 2/2 College Street Music Hall New Haven, CT
MON 2/4 Rams Head Live! Baltimore, MD
TUE 2/5 The National Richmond, VA
WED 2/6 The NorVa Norfolk, VA
FRI 2/8 The Fillmore Charlotte Charlotte, NC
SAT 2/9 House of Blues Myrtle Beach North Myrtle Beach, SC
MON 2/11 House of Blues Orlando Lake Buena Vista, FL
TUE 2/12 Jannus Live St. Petersburg, FL
THU 2/14 Thomas Wolfe Auditorium Asheville, NC
FRI 2/15 Georgia Theatre Athens, GA
SAT 2/16 The Signal Chattanooga, TN
SUN 2/17 The Mill & Mine Knoxville, TN
About WALK THE MOON
Hailing from Cincinnati, OH, WALK THE MOON consists of Nicholas Petricca (singer/keyboardist), Kevin Ray (bassist), Eli Maiman (guitarist), and Sean Waugaman (drummer). In 2015, the band catapulted to stardom when their hit single "Shut Up and Dance", which is included on their RIAA Certified Gold album TALKING IS HARD, became a multi-platinum global smash that peaked at No. 1 on the Alternative, Hot AC, AC charts, No. 4 on the Billboard Hot 100, aand went to No. 2 at Top 40 radio. The track also broke the record for consecutive weeks at #1 on Billboard's Hot Rock Songs chart at the time. "Shut Up and Dance" racked up over six million downloads and 850 million streams in the process leading to a slew of honors including winning two Billboard Music Awards, a nomination for an MTV Music Video Award for Best Rock Video, American Music Award nominations for Favorite Pop/Rock Duo Or Group, New Artist of the Year, and Favorite Alternative Rock Artist. They were also nominated for an iHeart Radio Music Award for Best Duo/Group of the Year, Song of the Year, and Alternative Rock Song of the Year for "Shut Up and Dance". WALK THE MOON has been praised by music industry tastemakers across the board since their explosive first single "Anna Sun" was released in 2012, as Interview Magazine proclaimed, "There's something about WALK THE MOON that's absolutely out of this world. Their music is addictive, energetic, and fun." Rolling Stone also raved about the band's live show, "The precocious Ohioans stack melodies upon melodies in new-wave-infected songs that attack the ear like a starving Mike Tyson." The band wrapped up their "Press Restart" Tour in support of What If Nothing and in the meantime, released the music video for their current single "Kamikaze" (Click HERE to watch).
Photo Credit: Brian Ziff
To Buy or Stream What If Nothing:
Multi Retailer: http://smarturl.it/WTMWhatIfNothing
Follow WALK THE MOON @
Official Site: http://www.walkthemoonband.com
Facebook: https://www.facebook.com/walkthemoon
Twitter: http://twitter.com/walkthemoonband
Instagram: http://instagram.com/walkthemoonband
YouTube: http://youtube.com/walkthemoonband
Vevo: http://www.youtube.com/user/WalkTheMoonVEVO


Help develop legislative priorities and policies to reform Wisconsin's transportation system.
Advise communities around the state on improving their transportation systems to be safer, more inclusive and cleaner.
Work with statewide coalitions on campaigns to reduce carbon emissions from the transportation system.
Carry out in-house research and publish reports to advance smart transportation policy.
Develop and maintain relationships with key media contacts and appear on media channels to promote our work.
Serve as needed on committees and leadership teams aligned with our mission.
Update transportation related social media.
Help identify foundations and granting organizations to bring in new revenue for the organization's transportation program.
Email Deb Nemeth at dnemeth@1kfriends.org to express interest.