Comment on Martinez-Garcia et al. 'Heavy metals in human bones in different historical epochs'.

Martínez-García et al. (Sci. Tot Env. 348:51–72) have examined heavy metal exposure of humans in the Cartagena region using analysis of archaeological bones. An analysis of the lead and iron levels they report shows that they are physiologically implausible and must therefore result from diagenesis. This, and analogy with the known diagenetic origin of certain other elements, suggests that the other metal analyses they report are also unlikely to be in vivo concentrations. Lifetime heavy metal exposure cannot be deduced from diagenetically altered concentrations

Theoretical and experimental analysis of the vacuum pressure in a vacuum glazing after extreme thermal cycling

Details of theoretical and experimental studies of the change in vacuum pressure within a vacuum glazing after extreme thermal cycling are presented. The vacuum glazing was fabricated at low temperature using an indium–copper–indium edge seal. It comprised two 4 mm thick 0.4 m by 0.4 m glass panes with low-emittance coatings separated by an array of stainless steel support pillars spaced at 25 mm with a diameter of 0.4 mm and a height of 0.15 mm. Thermal cycling tests were undertaken in which the air temperature on one side of the sample was taken from −30 °C to +50 °C and back to −30 °C 15 times while maintaining an air temperature of 22 °C on the other side. After this test procedure, it was found that the glass to glass heat conductance at the centre glazing area had increased by 10.1% from which the vacuum pressure within the evacuated space was determined to have increased from the negligible level of less than 0.1 Pa to 0.16 Pa using the model of Corrucini. Previous research has shown that if the vacuum pressure is less than 0.1 Pa, the effect of conduction through the residual gas on the total glazing heat transfer is negligible. The degradation of vacuum level determined was corroborated by the change in glass surface temperatures

Strong Coupling Corrections to the Ginzburg-Landau Theory of Superfluid ^{3}He

In the Ginzburg-Landau theory of superfluid $^{3}$He, the free energy is expressed as an expansion of invariants of a complex order parameter. Strong coupling effects, which increase with increasing pressure, are embodied in the set of coefficients of these order parameter invariants\cite{Leg75,Thu87}. Experiments can be used to determine four independent combinations of the coefficients of the five fourth order invariants. This leaves the phenomenological description of the thermodynamics near $T_{c}$ incomplete. Theoretical understanding of these coefficients is also quite limited. We analyze our measurements of the magnetic susceptibility and the NMR frequency shift in the $B$-phase which refine the four experimental inputs to the phenomenological theory. We propose a model based on existing experiments, combined with calculations by Sauls and Serene\cite{Sau81} of the pressure dependence of these coefficients, in order to determine all five fourth order terms. This model leads us to a better understanding of the thermodynamics of superfluid $^{3}$He in its various states. We discuss the surface tension of bulk superfluid $^{3}$He and predictions for novel states of the superfluid such as those that are stabilized by elastic scattering of quasiparticles from a highly porous silica aerogel.Comment: 9 pages, 7 figures, 2 table

A Culturally Competent Phenotypic Evaluation / Obesity Assessment in African and African American Populations: Pilot Study

BMI, a ratio of weight over height, is a culturally-biased tool imposed upon the scientific, academic and medical communities as an errant measure of obesity across ethnic - ity. Body Mass Index (BMI) relates mass (g) to a relative fat distribution with regards to height. Its genesis is from the actuarially derived and ethnically exclusive height and weight tables that promote the fictional notion of inter-eth - nic ideal weights that would be later adopted by the Na - tional Institutes of Health (NIH) as a competent measure of adiposity. Best practice, movement towards individualized medicine and deployment of effective models that impact the diabetes epidemic and its related precursors like insulin resistance and the metabolic syndrome, requires terminal use of BMI, a biologically meaningless and crude indicator of obesity, in favor of effective and culturally competent non-relative body composition evaluation of genetically determined adiposity that untenably compares values among groups. African Americans are among the increasingly affected groups for diabetes and posses unique composition variation requiring proper intra-cultural evaluation independent of inter-ethnic Eurocentric assumptions that over assesses obesity risk. Incorporating use of 4C models to evaluate adiposity and assess risk for diabetic predisposition and onset provides an effective unbiased assessment of the cultural components inherent within body composition variation among ethnicity, age, gender. Obesity and type II diabetes onset and pre-disposition is assessed phenotypically, in creation of a body mass profile among African and African American groups, using 4C model, photography, anthropometry, somatotype and genetic evaluation. Environmental obeseogenic cultural factors are also explored