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Population Trends and Variation in Body Mass Index from 1971 to 2008 in the Framingham Heart Study Offspring Cohort
Objective: We examined body mass index (BMI) across place and time to determine the pattern of BMI mean and standard deviation trajectories. Methods: We included participants in the Framingham Heart Study (FHS) Offspring Cohort over eight waves of follow-up, from 1971 to 2008. After exclusions, the final sample size was 4569 subjects with 28,625 observations. We used multi-level models to examine population means and variation at the individual and neighborhood (census tracts) levels across time with measured BMI as the outcome, controlling for individual demographics and behaviors and neighborhood poverty. Because neighborhoods accounted for limited BMI variance, we removed this level as a source of variation in final models. We examined sex-stratified models with all subjects and models stratified by sex and baseline weight classification. Results: Mean BMI increased from 24.0 kg/m2 at Wave 1 to 27.7 at Wave 8 for women and from 26.6 kg/m2 to 29.0 for men. In final models, BMI variation also increased from Waves 1 to 8, with the standard deviation increasing from 4.18 kg/m2 to 6.15 for women and 3.31 kg/m2 to 4.73 for men. BMI means increased in parallel across most baseline BMI weight classifications, except for more rapid increases through middle-age for obese women followed by declines in the last wave. BMI standard deviations also increased in parallel across baseline BMI classifications for women, with greater divergence of BMI variance for obese men compared to other weight classifications. Conclusion: Over nearly 40 years, BMI mean and variation increased in parallel across most baseline weight classifications in our sample. Individual-level characteristics, especially baseline BMI, were the primary factors in rising BMI. These findings have important implications not only for understanding the sources of the obesity epidemic in the United States but also for the targeting of interventions to address the epidemic
Donor states in modulation-doped Si/SiGe heterostructures
We present a unified approach for calculating the properties of shallow
donors inside or outside heterostructure quantum wells. The method allows us to
obtain not only the binding energies of all localized states of any symmetry,
but also the energy width of the resonant states which may appear when a
localized state becomes degenerate with the continuous quantum well subbands.
The approach is non-variational, and we are therefore also able to evaluate the
wave functions. This is used to calculate the optical absorption spectrum,
which is strongly non-isotropic due to the selection rules. The results
obtained from calculations for Si/SiGe quantum wells allow us to
present the general behavior of the impurity states, as the donor position is
varied from the center of the well to deep inside the barrier. The influence on
the donor ground state from both the central-cell effect and the strain arising
from the lattice mismatch is carefully considered.Comment: 17 pages, 10 figure
Transverse lattice calculation of the pion light-cone wavefunctions
We calculate the light-cone wavefunctions of the pion by solving the meson
boundstate problem in a coarse transverse lattice gauge theory using DLCQ. A
large-N_c approximation is made and the light-cone Hamiltonian expanded in
massive dynamical fields at fixed lattice spacing. In contrast to earlier
calculations, we include contributions from states containing many gluonic
link-fields between the quarks.The Hamiltonian is renormalised by a combination
of covariance conditions on boundstates and fitting the physical masses M_rho
and M_pi, decay constant f_pi, and the string tension sigma. Good covariance is
obtained for the lightest 0^{-+} state, which we identify with the pion. Many
observables can be deduced from its light-cone wavefunctions.After perturbative
evolution,the quark valence structure function is found to be consistent with
the experimental structure function deduced from Drell-Yan pi-nucleon data in
the valence region x > 0.5. In addition, the pion distribution amplitude is
consistent with the experimental distribution deduced from the pi gamma^* gamma
transition form factor and diffractive dissociation. A new observable we
calculate is the probability for quark helicity correlation. We find a 45%
probability that the valence-quark helicities are aligned in the pion.Comment: 27 pages, 9 figure
Regulation of phosphorylase kinase by low concentrations of Ca ions upon muscle contraction: the connection between metabolism and muscle contraction and the connection between muscle physiology and Ca-dependent signal transduction
It had long been one of the crucial questions in muscle physiology how glycogenolysis is regulated in connection with muscle contraction, when we found the answer to this question in the last half of the 1960s. By that time, the two principal currents of muscle physiology, namely, the metabolic flow starting from glycogen and the mechanisms of muscle contraction, had already been clarified at the molecular level thanks to our senior researchers. Thus, the final question we had to answer was how to connect these two currents. We found that low concentrations of Ca ions (10−7–10−4 M) released from the sarcoplasmic reticulum for the regulation of muscle contraction simultaneously reversibly activate phosphorylase kinase, the enzyme regulating glycogenolysis. Moreover, we found that adenosine 3′,5′-monophosphate (cyclic AMP), which is already known to activate muscle phosphorylase kinase, is not effective in the absence of such concentrations of Ca ions. Thus, cyclic AMP is not effective by itself alone and only modifies the activation process in the presence of Ca ions (at that time, cyclic AMP-dependent protein kinase had not yet been identified). After a while, it turned out that our works have not only provided the solution to the above problem on muscle physiology, but have also been considered as the first report of Ca-dependent protein phosphorylation, which is one of the central problems in current cell biology. Phosphorylase kinase is the first protein kinase to phosphorylate a protein resulting in the change in the function of the phosphorylated protein, as shown by Krebs and Fischer. Our works further showed that this protein kinase is regulated in a Ca-dependent manner. Accordingly, our works introduced the concept of low concentrations of Ca ions, which were first identified as the regulatory substance of muscle contraction, to the vast field of Ca biology including signal transduction
Biomarkers of Multiple Sclerosis
The search for an ideal multiple sclerosis biomarker with good diagnostic value, prognostic reference and an impact on clinical outcome has yet to be realized and is still ongoing. The aim of this review is to establish an overview of the frequent biomarkers for multiple sclerosis that exist to date. The review summarizes the results obtained from electronic databases, as well as thorough manual searches. In this review the sources and methods of biomarkers extraction are described; in addition to the description of each biomarker, determination of the prognostic, diagnostic, disease monitoring and treatment response values besides clinical impact they might possess. We divided the biomarkers into three categories according to the achievement method: laboratory markers, genetic-immunogenetic markers and imaging markers. We have found two biomarkers at the time being considered the gold standard for MS diagnostics. Unfortunately, there does not exist a single solitary marker being able to present reliable diagnostic value, prognostic value, high sensitivity and specificity as well as clinical impact. We need more studies to find the best biomarker for MS.publishersversionPeer reviewe
Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020
We show the distribution of SARS-CoV-2 genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three available genomic nomenclature systems for SARS-CoV-2 to all sequence data from the WHO European Region available during the COVID-19 pandemic until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation. We provide a comparison of the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2.Peer reviewe
Measurement of the mass difference between top quark and antiquark in pp collisions at root s=8 TeV
Peer reviewe
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