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Background/objectives: Recent evidence suggests nonconstant nature of dispersion in adult women's body mass index (BMI) across sociodemographic groups. The overall variances in BMI and height are also shown to have substantially changed over time. We modeled complex variation in adults' anthropometry-BMI and height-by wealth and education, and assessed their differences over time in India.Subjects/methods: Data from a total of 768,130 women and 180,691 men from the Indian National Family Health Survey (NFHS) 2006 and 2016 were used for the analysis. The average association between wealth and education with anthropometry was assessed from linear regression models assuming constant variance. Individual heterogeneity was modeled to obtain separate variances in anthropometry for each wealth quintile and education level. All analyses were stratified by survey year and sex.Results: On average, the positive socioeconomic gradient in adult's BMI and height persisted over time with slight attenuation. The residual variance in BMI ranged from 10.1 to 14.9 (7.2-11.3) by education level and 6.1 to 17.4 (5.0-13.0) by household wealth for women (men) in 2006, and they increased over time for the lower socioeconomic groups but remained the same or decreased for the higher socioeconomic groups. No significant pattern was observed for variation in height for both genders.Conclusions: We found potential reversal in the socioeconomic patterning in BMI variability in India as suggested by the increasing dispersion among the least educated and poorest populations. For a comprehensive understanding of nutrition transition in developing countries, it is necessary to assess the changes in means and variances of anthropometry in tandem. [ABSTRACT FROM AUTHOR]

This paper examines the trends in economic inequalities with respect to infant and child mortality in India using three rounds of the Indian National Family Health Survey conducted in 1992–1993, 1998–1999, and 2005–2006. The paper uses concentration index, and pooled discrete-time survival regression model to examine the aforementioned trends and regional patterns. The findings suggest a decreasing trend in economic inequality in infant mortality but an upward trend in economic inequality in child mortality in India. Economic inequalities in infant mortality have narrowed in the southern region, whereas they have widened in the western region and risen in the northern region. However, mixed trends in concentration indices were found in the different regions of India in the case of child mortality. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the homogeneous cooling stage (HCS) of a granular gas. The study introduced the granular temperature and applied the law of conservation of momentum to the instantaneous collision to define the temperature in kinetic theory of gases. Results show that by using the derived formula for granular materials consisting of viscoelastic particles, the cooling of viscoelastic grains is slower than grains with constant e.

Dimensional analysis is a powerful instrument in the physicist's arsenal, It not only helps to check equations, but can also be used to derive important ones. We illustrate this by deriving some important expressions in black hole physics. Starting with a simple input, namely that the properties of an uncharged, non-rotating black hole depend only on the mass (that 'no hair theorem') we employ dimensional analysis to derive expressions for the area of the event horizon, the entropy, the evaporation time and the Hawking temperature, among others. Our derivations are accessible to pre-college students, but its exotic implications may leave them pondering for a very long time. [ABSTRACT FROM AUTHOR]

The Coulomb blockade (CB) in quantum dots (QDs) is by now well documented. It has been used to guide the fabrication of single electron transistors. Even the most sophisticated techniques for synthesizing QDs (e.g. MOCVD/MBE) result in an assembly in which a certain amount of disorder is inevitable. On the other hand, theoretical approaches to CB limit themselves to an analysis of a single QD. In the present work we consider two types of disorders: (i) size disorder; e.g. QDs have a distribution of sizes which could be unimodal or bimodal in nature. (ii) Potential disorder with the confining potential assuming a variety of shapes depending on growth condition and external fields. We assume a Gaussian distribution in disorder in both size and potential and employ a simplified mean field theory. To do this we rely on the scaling laws for the CB (also termed as Hubbard U) obtained for an isolated QD [1]. We analyze the distribution in the Hubbard U as a consequence of disorder and observe that Coulomb blockade is partially suppressed by the disorder. Further, the distribution in U is a skewed Gaussian with enhanced broadening. [ABSTRACT FROM AUTHOR]

Impurities play a pivotal role in semiconductors. One part in a million of phosphorous in silicon alters the conductivity of the latter by several orders of magnitude. Indeed, the information age is possible only because of the unique role of shallow impurities in semiconductors. Although work in semiconductor nanostructures (SN) has been in progress for the past two decades, the role of impurities in them has been only sketchily studied. We outline theoretical approaches to the electronic structure of shallow impurities in SN and discuss their limitations. We find that shallow levels undergo a SHADES (SHAllow-DEep-Shallow) transition as the SN size is decreased. This occurs because of the combined effect of quantum confinement and reduced dielectric constant in SN. Level splitting is pronounced and this can perhaps be probed by ESR and ENDOR techniques. Finally, we suggest that a perusal of literature on (semiconductor) cluster calculations carried out 30 years ago would be useful. [ABSTRACT FROM AUTHOR]

The article presents several examples of Fermi problems adapted from the 37th International Physics Olympiad (IPO) held in Singapore from July 8-17, 2006. The two effects that were used to determine the camera's effectiveness as a photographic tool are diffraction by the aperture and the pixel size. It cites the amount of cooking time needed to make a hard-boiled egg. The solution to know the frames in an animation movie is presented.