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Associations between physical activity and BMI, body fatness, and visceral adiposity in overweight or obese Latino and non-Latino adults.
Background/objectivesAlthough several studies have reported associations between moderate to vigorous physical activity (MVPA), body fatness and visceral adipose tissue (VAT), the extent to which associations differ among Latinos and non-Latinos remains unclear. This study evaluated the associations between body composition and MVPA in Latino and non-Latino adults.Subjects/methodsAn exploratory, cross-sectional analysis was conducted using baseline data collected from 298 overweight adults enrolled in a 12-month randomized controlled trial that tested the efficacy of text messaging to improve weight loss. MVPA, body fatness and VAT were assessed by waist-worn accelerometry, dual-energy x-ray absorptiometry (DXA), and DXA-derived software (GE CoreScan GE, Madison, WI, USA), respectively. Participants with <5 days of accelerometry data or missing DXA data were excluded; 236 participants had complete data. Multivariable linear regression assessed associations between body composition and MVPA per day, defined as time in MVPA, bouts of MVPA (time per bout ⩾10 min), non-bouts of MVPA (time per bout <10 min) and meeting the 150-min MVPA guideline. The modifying influence of ethnicity was modeled with a multiplicative interaction term.ResultsThe interaction between ethnicity and MVPA in predicting percent body fat was significant (P=0.01, 95% confidence interval (CI) (0.58, 4.43)) such that a given increase in MVPA was associated with a greater decline in total body fat in non-Latinos compared with Latinos (adjusted for age, sex and accelerometer wear time). There was no interaction between ethnicity and MVPA in predicting VAT (g) (P=0.78, 95% CI (-205.74, 273.17)) and body mass index (BMI) (P=0.18, 95% CI (-0.49, 2.26)).ConclusionsAn increase in MVPA was associated with a larger decrease in body fat, but neither BMI nor VAT, in non-Latinos compared with Latinos. This suggests that changes in VAT and BMI in response to MVPA may be less influenced by ethnicity than is total body fatness
[N]pT Monte Carlo Simulations of the Cluster-Crystal-Forming Penetrable Sphere Model
Certain models with purely repulsive pair interactions can form cluster
crystals with multiply-occupied lattice sites. Simulating these models'
equilibrium properties is, however, quite challenging. Here, we develop an
expanded isothermal-isobaric ensemble that surmounts this problem by
allowing both particle number and lattice spacing to fluctuate. We apply the
method with a Monte Carlo simulation scheme to solve the phase diagram of a
prototypical cluster-crystal former, the penetrable sphere model (PSM), and
compare the results with earlier theoretical predictions. At high temperatures
and densities, the equilibrium occupancy of
face-centered cubic (FCC) crystal increases linearly. At low temperatures,
although plateaus at integer values, the crystal
behavior changes continuously with density. The previously ambiguous crossover
around is resolved
Looking on the bright side of life: Gratitude and experiences of interpersonal transgressions in adulthood and daily life
OBJECTIVE: Gratitude plays an important role in individual and social well-being. However, less is known about the link between gratitude and experiences of interpersonal stressors. The current research examined the associations between gratitude and interpersonal transgressions.
METHOD: One cross-sectional study with a broad age range and two daily diary studies (total NÂ =Â 2,348; total age range: 18-91) were used to test the associations on the between- and within-person level.
RESULTS: A consistent result across all studies was that dispositionally grateful individuals tended to report fewer interpersonal transgressions than less grateful people. In turn, people who generally reported more interpersonal transgressions were less grateful in daily life. Moreover, higher gratitude on one specific day was associated with fewer reported transgressions on the same day. However, the results from the daily diary studies indicated differences between the samples. Whereas gratitude was consistently associated with interpersonal transgressions in one daily diary sample, the findings in the second daily diary sample were less consistent.
CONCLUSION: The present findings suggest that grateful people tend to perceive their social exchanges differently and/or actually experience fewer interpersonal transgressions. Future work is needed to test the underlying mechanisms of this negative association
The wall shear rate distribution for flow in random sphere packings
The wall shear rate distribution P(gamma) is investigated for pressure-driven
Stokes flow through random arrangements of spheres at packing fractions 0.1 <=
phi <= 0.64. For dense packings, P(gamma) is monotonic and approximately
exponential. As phi --> 0.1, P(gamma) picks up additional structure which
corresponds to the flow around isolated spheres, for which an exact result can
be obtained. A simple expression for the mean wall shear rate is presented,
based on a force-balance argument.Comment: 4 pages, 3 figures, 1 table, RevTeX 4; significantly revised with
significantly extended scop
Hydrogel microparticles for biosensing
Due to their hydrophilic, biocompatible, and highly tunable nature, hydrogel materials have attracted strong interest in the recent years for numerous biotechnological applications. In particular, their solution-like environment and non-fouling nature in complex biological samples render hydrogels as ideal substrates for biosensing applications. Hydrogel coatings, and later, gel dot surface microarrays, were successfully used in sensitive nucleic acid assays and immunoassays. More recently, new microfabrication techniques for synthesizing encoded particles from hydrogel materials have enabled the development of hydrogel-based suspension arrays. Lithography processes and droplet-based microfluidic techniques enable generation of libraries of particles with unique spectral or graphical codes, for multiplexed sensing in biological samples. In this review, we discuss the key questions arising when designing hydrogel particles dedicated to biosensing. How can the hydrogel material be engineered in order to tune its properties and immobilize bioprobes inside? What are the strategies to fabricate and encode gel particles, and how can particles be processed and decoded after the assay? Finally, we review the bioassays reported so far in the literature that have used hydrogel particle arrays and give an outlook of further developments of the field. Keywords: Hydrogel; Biosensor; Microparticle; Multiplex assayNovartis Institutes of Biomedical Research (Presidential Fellowship)Novartis Institutes of Biomedical Research (Education Office)National Cancer Institute (U.S.) (Grant 5R21CA177393-02)National Science Foundation (U.S.) (Grant CMMI-1120724)Institute for Collaborative Biotechnologies (Grant W911NF-09-0001)United States. Army Research Offic
Phase behavior of a confined nano-droplet in the grand-canonical ensemble: the reverse liquid-vapor transition
The equilibrium density distribution and thermodynamic properties of a
Lennard-Jones fluid confined to nano-sized spherical cavities at constant
chemical potential was determined using Monte Carlo simulations. The results
describe both a single cavity with semipermeable walls as well as a collection
of closed cavities formed at constant chemical potential. The results are
compared to calculations using classical Density Functional Theory (DFT). It is
found that the DFT calculations give a quantitatively accurate description of
the pressure and structure of the fluid. Both theory and simulation show the
presence of a ``reverse'' liquid-vapor transition whereby the equilibrium state
is a liquid at large volumes but becomes a vapor at small volumes.Comment: 13 pages, 8 figures, to appear in J. Phys. : Cond. Mat
System and Method for Null-Lens Wavefront Sensing
A method of measuring aberrations in a null-lens including assembly and alignment aberrations. The null-lens may be used for measuring aberrations in an aspheric optic with the null-lens. Light propagates from the aspheric optic location through the null-lens, while sweeping a detector through the null-lens focal plane. Image data being is collected at locations about said focal plane. Light is simulated propagating to the collection locations for each collected image. Null-lens aberrations may extracted, e.g., applying image-based wavefront-sensing to collected images and simulation results. The null-lens aberrations improve accuracy in measuring aspheric optic aberrations
TCT-294: Long-Term (Three Years) Follow-Up of the Patients with Multiple Sirolimus Eluting Stent Implantation (Full-metal Jacket Patients)
1. The cost, usability and power efficiency of available wildlife monitoring equipment currently inhibits full ground-level coverage of many natural systems. Developments over the last decade in technology, open science, and the sharing economy promise to bring global access to more versatile and more affordable monitoring tools, to improve coverage for conservation researchers and managers.
2. Here we describe the development and proof-of-concept of a low-cost, small-sized and low-energy acoustic detector: 'AudioMoth'. The device is open-source and programmable, with diverse applications for recording animal calls or human activity at sample rates of up to 384kHz. We briefly outline two ongoing real-world case studies of large-scale, long-term monitoring for biodiversity and exploitation of natural resources. These studies demonstrate the potential for AudioMoth to enable a substantial shift away from passive continuous recording by individual devices, towards smart detection by networks of devices flooding large and inaccessible ecosystems.
3. The case studies demonstrate one of the smart capabilities of AudioMoth, to trigger event logging on the basis of classification algorithms that identify specific acoustic events. An algorithm to trigger recordings of the New Forest cicada (Cicadetta montana) demonstrates the potential for AudioMoth to vastly improve the spatial and temporal coverage of surveys for the presence of cryptic animals. An algorithm for logging gunshot events has potential to identify a shotgun blast in tropical rainforest at distances of up to 500 m, extending to 1km with continuous recording.
4. AudioMoth is more energy efficient than currently available passive acoustic monitoring (PAM) devices, giving it considerably greater portability and longevity in the field with smaller batteries. At a build cost of ~US$43 per unit, AudioMoth has potential for varied applications in large-scale, long-term acoustic surveys. With continuing developments in smart, energy-efficient algorithms and diminishing component costs, we are approaching the milestone of local communities being able to afford to remotely monitor their own natural resources
Magnetic Quantum Tunneling: Insights from Simple Molecule-Based Magnets
This article takes a broad view of the understanding of magnetic bistability
and magnetic quantum tunneling in single-molecule magnets (SMMs), focusing on
three families of relatively simple, low-nuclearity transition metal clusters:
spin S = 4 Ni4, Mn(III)3 (S = 2 and 6) and Mn(III)6 (S = 4 and 12). The Mn(III)
complexes are related by the fact that they contain triangular Mn3 units in
which the exchange may be switched from antiferromagnetic to ferromagnetic
without significantly altering the coordination around the Mn(III) centers,
thereby leaving the single-ion physics more-or-less unaltered. This allows for
a detailed and systematic study of the way in which the individual-ion
anisotropies project onto the molecular spin ground state in otherwise
identical low- and high-spin molecules, thus providing unique insights into the
key factors that control the quantum dynamics of SMMs, namely: (i) the height
of the kinetic barrier to magnetization relaxation; and (ii) the transverse
interactions that cause tunneling through this barrier. Numerical calculations
are supported by an unprecedented experimental data set (17 different
compounds), including very detailed spectroscopic information obtained from
high-frequency electron paramagnetic resonance and low-temperature hysteresis
measurements. Diagonalization of the multi-spin Hamiltonian matrix is necessary
in order to fully capture the interplay between exchange and local anisotropy,
and the resultant spin-state mixing which ultimately gives rise to the
tunneling matrix elements in the high symmetry SMMs (ferromagnetic Mn3 and
Ni4). The simplicity (low-nuclearity, high-symmetry, weak disorder, etc..) of
the molecules highlighted in this study proves to be of crucial importance.Comment: 32 pages, incl. 6 figure
Avenues of future research in homotransplantation of the liver with particular reference to hepatic supportive procedures, antilymphocyte serum, and tissue typing
Three general areas of research which bear on the developing field of liver transplantation are reviewed. These are: (1) the prospects of obtaining better immunosuppression with particular reference to heterologous antilymphocyte serum; (2) the possible use of antigen matching technics as an advanced indicator of donorrecipient histocompatibility; (3) a simlified system of extracorporeal transplntation designed to provide teporary hepatic support. © 1966
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