3,612 research outputs found
Marital Satisfaction and Inflammatory Functioning: A Biopsychosocial Pathway to Health - A Meta-Analytic Review
Master's ThesisMarriage is a dominant relationship among adults and has been shown to impact physical
and mental health. The exact pathway to describe its impact remains unclear, but recent advances in the literature focus on a biopsychosocial approach integrating affective, behavioral, and physiological correlates. Combined, these pathways can be best illustrated through a stress buffering model. Using theoretical and methodological conceptualizations of the physiological impact of acute and chronic stress, we review how marital satisfaction, a descriptor of marital functioning, impacts health through altered inflammatory functioning. Using a meta-analytic design, seven published empirical articles spanning over the last 30 years in 2, 349 individuals were reviewed, evaluating the association between marital satisfaction and immunological biomarkers associated with inflammation: C-reactive protein, interleukin-6, interleukin-1 beta, and tumor necrosis factor-alpha. Marital satisfaction was not significantly related to inflammation, and effect sizes remained insignificant after accounting for moderators such as year of publication and inflammatory marker. The conclusions are limited by sample size, and
exclusion of conflict variables, and the use of a statistical design that limits the interpretation of causal inferences. Future implications of these findings, highlighting a need to focus on moderating factors among marital satisfaction, inflammatory functioning, and health are discussed.https://deepblue.lib.umich.edu/bitstream/2027.42/146764/1/Corso - Marital Satisfaction and Inflammatory Functioning A Biopsychosocial Pathway to Health - A Meta-Physical Review.pdf13Description of Corso - Marital Satisfaction and Inflammatory Functioning A Biopsychosocial Pathway to Health - A Meta-Physical Review.pdf : Master's Thesi
Mechanical Mixing in Nonlinear Nanomechanical Resonators
Nanomechanical resonators, machined out of Silicon-on-Insulator wafers, are
operated in the nonlinear regime to investigate higher-order mechanical mixing
at radio frequencies, relevant to signal processing and nonlinear dynamics on
nanometer scales. Driven by two neighboring frequencies the resonators generate
rich power spectra exhibiting a multitude of satellite peaks. This nonlinear
response is studied and compared to -order perturbation theory and
nonperturbative numerical calculations.Comment: 5 pages, 7 figure
Single molecule imaging with longer x-ray laser pulses
During the last five years, serial femtosecond crystallography using x-ray
laser pulses has developed into a powerful technique for determining the atomic
structures of protein molecules from micrometer and sub-micrometer sized
crystals. One of the key reasons for this success is the "self-gating" pulse
effect, whereby the x-ray laser pulses do not need to outrun all radiation
damage processes. Instead, x-ray induced damage terminates the Bragg
diffraction prior to the pulse completing its passage through the sample, as if
the Bragg diffraction was generated by a shorter pulse of equal intensity. As a
result, serial femtosecond crystallography does not need to be performed with
pulses as short as 5--10 fs, as once thought, but can succeed for pulses
50--100 fs in duration. We show here that a similar gating effect applies to
single molecule diffraction with respect to spatially uncorrelated damage
processes like ionization and ion diffusion. The effect is clearly seen in
calculations of the diffraction contrast, by calculating the diffraction of
average structure separately to the diffraction from statistical fluctuations
of the structure due to damage ("damage noise"). Our results suggest that
sub-nanometer single molecule imaging with 30--50 fs pulses, like those
produced at currently operating facilities, should not yet be ruled out. The
theory we present opens up new experimental avenues to measure the impact of
damage on single particle diffraction, which is needed to test damage models
and to identify optimal imaging conditions.Comment: 23 pages; 5 figure
Supersolid phases of light in extended Jaynes-Cummings-Hubbard systems
Jaynes-Cummings-Hubbard lattices provide unique properties for the study of
correlated phases as they exhibit convenient state preparation and measurement,
as well as "in situ" tuning of parameters. We show how to realize charge
density and supersolid phases in Jaynes-Cummings-Hubbard lattices in the
presence of long-range interactions. The long-range interactions are realized
by the consideration of Rydberg states in coupled atom-cavity systems and the
introduction of additional capacitive couplings in quantum-electrodynamics
circuits. We demonstrate the emergence of supersolid and checkerboard solid
phases, for calculations which take into account nearest neighbour couplings,
through a mean-field decoupling.Comment: 9 pages with 6 figures, accepted for publication in Physical Review
Charge tedistribution and transport in molecular contacts
Under the terms of the Creative Commons Attribution License 3.0 (CC-BY).-- et al.The forces between two single molecules brought into contact, and their connection with charge transport through the molecular junction, are studied here using non contact AFM, STM, and density functional theory simulations. A carbon monoxide molecule approaching an acetylene molecule (C2H2) initially feels weak attractive electrostatic forces, partly arising from charge reorganization in the presence of molecular. We find that the molecular contact is chemically passive, and protects the electron tunneling barrier from collapsing, even in the limit of repulsive forces. However, we find subtle conductance and force variations at different contacting sites along the C2H2 molecule attributed to a weak overlap of their respective frontier orbitals.The research was supported by DFG (Grant No. Sfb 658), the Czech Science Foundation (GAÄŒR) Project No. 14-02079S, GAAV Grant No. M100101207, and the Spanish MINECO (Grant No. MAT2013-46593-C6-01). M. C. acknowledges support from the Alexander von Humboldt Foundation.Peer Reviewe
First-principles study of lattice instabilities in the ferromagnetic martensite NiMnGa
The phonon dispersion relations and elastic constants for ferromagnetic
NiMnGa in the cubic and tetragonally distorted Heusler structures are
computed using density-functional and density-functional perturbation theory
within the spin-polarized generalized-gradient approximation. For
, the TA tranverse acoustic branch along and
symmetry-related directions displays a dynamical instability at a wavevector
that depends on . Through examination of the Fermi-surface nesting and
electron-phonon coupling, this is identified as a Kohn anomaly. In the parent
cubic phase the computed tetragonal shear elastic constant,
C=(CC)/2, is close to zero, indicating a marginal
elastic instability towards a uniform tetragonal distortion. We conclude that
the cubic Heusler structure is unstable against a family of energy-lowering
distortions produced by the coupling between a uniform tetragonal distortion
and the corresponding modulation. The computed relation between the
ratio and the modulation wavevector is in excellent agreement with
structural data on the premartensitic ( = 1) and martensitic ( =
0.94) phases of NiMnGa.Comment: submitted to Phys. Rev.
Serre's "formule de masse" in prime degree
For a local field F with finite residue field of characteristic p, we
describe completely the structure of the filtered F_p[G]-module K^*/K^*p in
characteristic 0 and $K^+/\wp(K^+) in characteristic p, where K=F(\root{p-1}\of
F^*) and G=\Gal(K|F). As an application, we give an elementary proof of Serre's
mass formula in degree p. We also determine the compositum C of all degree p
separable extensions with solvable galoisian closure over an arbitrary base
field, and show that C is K(\root p\of K^*) or K(\wp^{-1}(K)) respectively, in
the case of the local field F. Our method allows us to compute the contribution
of each character G\to\F_p^* to the degree p mass formula, and, for any given
group \Gamma, the contribution of those degree p separable extensions of F
whose galoisian closure has group \Gamma.Comment: 36 pages; most of the new material has been moved to the new Section
Climate drives long-term change in Antarctic Silverfish along the western Antarctic Peninsula
Over the last half of the 20th century, the western Antarctic Peninsula has been one of the most rapidly warming regions on Earth, leading to substantial reductions in regional sea ice coverage. These changes are modulated by atmospheric forcing, including the Amundsen Sea Low (ASL) pressure system. We utilized a novel 25-year (1993–2017) time series to model the effects of environmental variability on larvae of a keystone species, the Antarctic Silverfish (Pleuragramma antarctica). Antarctic Silverfish use sea ice as spawning habitat and are important prey for penguins and other predators. We show that warmer sea surface temperature and decreased sea ice are associated with reduced larval abundance. Variability in the ASL modulates both sea surface temperature and sea ice; a strong ASL is associated with reduced larvae. These findings support a narrow sea ice and temperature tolerance for adult and larval fish. Further regional warming predicted to occur during the 21st century could displace populations of Antarctic Silverfish, altering this pelagic ecosystem
Enhancement of piezoelectricity in a mixed ferroelectric
We use first-principles density-functional total energy and polarization
calculations to calculate the piezoelectric tensor at zero temperature for both
cubic and simple tetragonal ordered supercells of Pb_3GeTe_4. The largest
piezoelectric coefficient for the tetragonal configuration is enhanced by a
factor of about three with respect to that of the cubic configuration. This can
be attributed to both the larger strain-induced motion of cations relative to
anions and higher Born effective charges in the tetragonal case. A normal mode
decomposition shows that both cation ordering and local relaxation weaken the
ferroelectric instability, enhancing piezoelectricity.Comment: 5 pages, revtex, 2 eps figure
Spontaneous polarization and piezoelectric constants of III-V nitrides
The spontaneous polarization, dynamical Born charges, and piezoelectric
constants of the III-V nitrides AlN, GaN, and InN are studied ab initio using
the Berry phase approach to polarization in solids. The piezoelectric constants
are found to be up 10 times larger than in conventional III-V's and II-VI's,
and comparable to those of ZnO. Further properties at variance with those of
conventional III-V compounds are the sign of the piezoelectric constants
(positive as in II-VI's) and the very large spontaneous polarization.Comment: RevTeX 4 pages, improved upon revie
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