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Effects of a Mindfulness-Based Intervention on Distress, Weight Gain, and Glucose Control for Pregnant Low-Income Women: A Quasi-Experimental Trial Using the ORBIT Model.
BackgroundStress can lead to excessive weight gain. Mindfulness-based stress reduction that incorporates mindful eating shows promise for reducing stress, overeating, and improving glucose control. No interventions have tested mindfulness training with a focus on healthy eating and weight gain during pregnancy, a period of common excessive weight gain. Here, we test the effectiveness of such an intervention, the Mindful Moms Training (MMT), on perceived stress, eating behaviors, and gestational weight gain in a high-risk sample of low income women with overweight/obesity.MethodWe conducted a quasi-experimental study assigning 115 pregnant women to MMT for 8 weeks and comparing them to 105 sociodemographically and weight equivalent pregnant women receiving treatment as usual. Our main outcomes included weight gain (primary outcome), perceived stress, and depression.ResultsWomen in MMT showed significant reductions in perceived stress (β = - 0.16) and depressive symptoms (β = - 0.21) compared to the treatment as usual (TAU) control group. Consistent with national norms, the majority of women (68%) gained excessive weight according to Institute of Medicine weight-gain categories, regardless of group. Slightly more women in the MMT group gained below the recommendation. Among secondary outcomes, women in MMT reported increased physical activity (β = 0.26) and had lower glucose post-oral glucose tolerance test (β = - 0.23), being 66% less likely to have impaired glucose tolerance, compared to the TAU group.ConclusionA short-term intervention led to significant improvements in stress, and showed promise for preventing glucose intolerance. However, the majority of women gained excessive weight. A longer more intensive intervention may be needed for this high-risk population. Clinical Trials.gov #NCT01307683
Classical and Quantum Solitons in the Symmetric Space Sine-Gordon Theories
We construct the soliton solutions in the symmetric space sine-Gordon
theories. The latter are a series of integrable field theories in
1+1-dimensions which are associated to a symmetric space F/G, and are related
via the Pohlmeyer reduction to theories of strings moving on symmetric spaces.
We show that the solitons are kinks that carry an internal moduli space that
can be identified with a particular co-adjoint orbit of the unbroken subgroup H
of G. Classically the solitons come in a continuous spectrum which encompasses
the perturbative fluctuations of the theory as the kink charge becomes small.
We show that the solitons can be quantized by allowing the collective
coordinates to be time-dependent to yield a form of quantum mechanics on the
co-adjoint orbit. The quantum states correspond to symmetric tensor
representations of the symmetry group H and have the interpretation of a fuzzy
geometric version of the co-adjoint orbit. The quantized finite tower of
soliton states includes the perturbative modes at the base.Comment: 53 pages, additional comments and small errors corrected, final
journal versio
Locally critical quantum phase transitions in strongly correlated metals
When a metal undergoes a continuous quantum phase transition, non-Fermi
liquid behaviour arises near the critical point. It is standard to assume that
all low-energy degrees of freedom induced by quantum criticality are spatially
extended, corresponding to long-wavelength fluctuations of the order parameter.
However, this picture has been contradicted by recent experiments on a
prototype system: heavy fermion metals at a zero-temperature magnetic
transition. In particular, neutron scattering from CeCuAu has
revealed anomalous dynamics at atomic length scales, leading to much debate as
to the fate of the local moments in the quantum-critical regime. Here we report
our theoretical finding of a locally critical quantum phase transition in a
model of heavy fermions. The dynamics at the critical point are in agreement
with experiment. We also argue that local criticality is a phenomenon of
general relevance to strongly correlated metals, including doped Mott
insulators.Comment: 20 pages, 3 figures; extended version, to appear in Natur
The Form Factors and Quantum Equation of Motion in the sine-Gordon Model
Using the methods of the 'form factor program' exact expressions of all
matrix elements are obtained for several operators of the quantum sine-Gordon
model alias the massive Thirring model. A general formula is presented which
provides form factors in terms of an integral representation. In particular
charge-less operators as for example the current of the topological charge, the
energy momentum tensor and all higher currents are considered. In the breather
sector it is found the quantum sine-Gordon field equation holds with an exact
relation between the 'bare' mass and the normalized mass. Also a relation for
the trace of the energy momentum is obtained. All results are compared with
Feynman graph expansion and full agreement is found.Comment: TCI-LaTeX, 21 pages with 2 figur
Optical signature of symmetry variations and spin-valley coupling in atomically thin tungsten dichalcogenides
Motivated by the triumph and limitation of graphene for electronic
applications, atomically thin layers of group VI transition metal
dichalcogenides are attracting extensive interest as a class of graphene-like
semiconductors with a desired band-gap in the visible frequency range. The
monolayers feature a valence band spin splitting with opposite sign in the two
valleys located at corners of 1st Brillouin zone. This spin-valley coupling,
particularly pronounced in tungsten dichalcogenides, can benefit potential
spintronics and valleytronics with the important consequences of spin-valley
interplay and the suppression of spin and valley relaxations. Here we report
the first optical studies of WS2 and WSe2 monolayers and multilayers. The
efficiency of second harmonic generation shows a dramatic even-odd oscillation
with the number of layers, consistent with the presence (absence) of inversion
symmetry in even-layer (odd-layer). Photoluminescence (PL) measurements show
the crossover from an indirect band gap semiconductor at mutilayers to a
direct-gap one at monolayers. The PL spectra and first-principle calculations
consistently reveal a spin-valley coupling of 0.4 eV which suppresses
interlayer hopping and manifests as a thickness independent splitting pattern
at valence band edge near K points. This giant spin-valley coupling, together
with the valley dependent physical properties, may lead to rich possibilities
for manipulating spin and valley degrees of freedom in these atomically thin 2D
materials
Water induced sediment levitation enhances downslope transport on Mars
On Mars, locally warm surface temperatures (~293 K) occur, leading to the possibility of (transient) liquid water on the surface. However, water exposed to the martian atmosphere will boil, and the sediment transport capacity of such unstable water is not well understood. Here, we present laboratory studies of a newly recognized transport mechanism: “levitation” of saturated sediment bodies on a cushion of vapor released by boiling. Sediment transport where this mechanism is active is about nine times greater than without this effect, reducing the amount of water required to transport comparable sediment volumes by nearly an order of magnitude. Our calculations show that the effect of levitation could persist up to ~48 times longer under reduced martian gravity. Sediment levitation must therefore be considered when evaluating the formation of recent and present-day martian mass wasting features, as much less water may be required to form such features than previously thought
Probing High Reheating Temperature Scenarios at the LHC with Long-Lived Staus
We investigate the possibility of probing high reheating temperature
scenarios at the LHC, in supersymmetric models where the gravitino is the
lightest supersymmetric particle, and the stau is the next-to-lightest
supersymmetric particle. In such scenarios, the big-bang nucleosynthesis and
the gravitino abundance give a severe upper bound on the gluino mass. We find
that, if the reheating temperature is \sim 10^8 GeV or higher, the scenarios
can be tested at the LHC with an integrated luminosity of O(1 fb^{-1}) at
\sqrt{s}=7 TeV in most of the parameter space.Comment: 17 pages, 5 figures, minor modification
Survival from breast cancer among South Asian and non-South Asian women resident in South East England
Ethnic differences in breast cancer survival have been observed in the USA but have not been examined in Britain. We aimed to investigate such differences between South Asian (i.e. those with family roots in the Indian subcontinent) and non-South Asian (essentially British-native) women in England. Primary breast cancer cases incident in 1986 -1993 and resident in South East England were ascertained through the Thames Cancer and Registry and followed up to the end of 1997. Cases of South Asian ethnicity were identified on the basis of their names by using a previously validated computer algorithm. A total of 1037 South Asian and 50 201 non-South Asian breast cancer cases were included in the analysis; 30% of the South Asian (n=312) and 44% (n=22 201) of the non-South Asian cases died during follow-up. South Asian cases had a higher relative survival than non-South Asians throughout the follow-up period. The 10-year relative survival rates were 72.6% (95% confidence interval: 69.0, 75.9%) and 65.2% (64.5, 65.8%) for South Asians and non-South Asians, respectively. The excess mortality rates experienced by South Asians were 82% (72, 94%) of those experienced by non-South Asians (P=0.004). The magnitude of this effect was slightly reduced with adjustment for differences in age at diagnosis, but was strengthened with further adjustment for differences in stage at presentation and socioeconomic deprivation (excess mortality rates in South Asians relative to non-South Asians=72% (63, 82%), P&<0.001). These findings indicate that the higher survival from breast cancer in the first 10 years after diagnosis among South Asian was not due to differences in age at diagnosis, socioeconomic deprivation or disease stage at presentation
Hierarchies of Susy Splittings and Invisible Photinos as Dark Matter
We explore how to generate hierarchies in the splittings between
superpartners. Some of the consequences are the existence of invisible
components of dark matter, new inflaton candidates, invisible monopoles and a
number of invisible particles that might dominate during various eras, in
particular between BBN and recombination and decay subsequently.Comment: 16 pages. v3: Ref. 27 has been modified. v4: Published versio
Cyborg Activism: Exploring the reconfigurations of democratic subjectivity in Anonymous
This article develops the concept of cyborg activism as novel configuration of democratic subjectivity in the Information Age by exploring the online collectivity Anonymous as a prototype. By fusing elements of human/machine and organic/digital the cyborg disrupts modern logics of binary thinking. Cyborg activism emerges as the reconfiguration of equality/hierarchy, reason/emotion, and nihilism/idealism. Anonymous demonstrates how through the use of contingent and ephemeral digital personae hierarchies in cyborg activism prove more volatile than in face-to-face settings. Emotions appear as an essential part of a politics of passion, which enables pursuing laughter and joy, expressing anger, and experiencing empowerment as part of a reasoned, strategic politics. Anonymous’ political content reconfigures nihilist sentiments, frustration, and political disenchantment on the one hand with idealist world views on the other. This enables the cohabitation and partial integration of a great diversity of political claims rooted in various ideologies
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