4,712 research outputs found
A TYPICAL FARM SERIES: DEVELOPMENT AND APPLICATION TO A MISSISSIPPI DELTA FARM
Farm Management,
Search for axion-like particles using a variable baseline photon regeneration technique
We report the first results of the GammeV experiment, a search for milli-eV
mass particles with axion-like couplings to two photons. The search is
performed using a "light shining through a wall" technique where incident
photons oscillate into new weakly interacting particles that are able to pass
through the wall and subsequently regenerate back into detectable photons. The
oscillation baseline of the apparatus is variable, thus allowing probes of
different values of particle mass. We find no excess of events above background
and are able to constrain the two-photon couplings of possible new scalar
(pseudoscalar) particles to be less than 3.1x10^{-7} GeV^{-1} (3.5x10^{-7}
GeV^{-1}) in the limit of massless particles.Comment: 5 pages, 4 figures. This is the version accepted by PRL and includes
updated limit
Asymptotic stability, concentration, and oscillation in harmonic map heat-flow, Landau-Lifshitz, and Schroedinger maps on R^2
We consider the Landau-Lifshitz equations of ferromagnetism (including the
harmonic map heat-flow and Schroedinger flow as special cases) for degree m
equivariant maps from R^2 to S^2. If m \geq 3, we prove that near-minimal
energy solutions converge to a harmonic map as t goes to infinity (asymptotic
stability), extending previous work down to degree m = 3. Due to slow spatial
decay of the harmonic map components, a new approach is needed for m=3,
involving (among other tools) a "normal form" for the parameter dynamics, and
the 2D radial double-endpoint Strichartz estimate for Schroedinger operators
with sufficiently repulsive potentials (which may be of some independent
interest). When m=2 this asymptotic stability may fail: in the case of
heat-flow with a further symmetry restriction, we show that more exotic
asymptotics are possible, including infinite-time concentration (blow-up), and
even "eternal oscillation".Comment: 34 page
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Predictive markers for humoral influenza vaccine response in patients with common variable immunodeficiency (CVID)
BACKGROUND: A subgroup of patients with common variable immunodeficiencies (CVID) responds to vaccination. The aim of the study was to try to identify predictive markers for those who developed a humoral immune response after influenza vaccination. METHODS: 48 patients with CVID (29 females, 19 males, mean age 59.4 years) were vaccinated with the A(H1N1) influenza vaccine Pandemrix® and boosted after one month. Blood samples were collected prior to each vaccination and two months later. Patients with a 4-fold titer increase of the hemagglutinin inhibition test (≥ 1:40) were considered responders and compared to non-responders for clinical, immunological and genetic markers. RESULTS: Eight (16.7%) patients responded to the vaccination. A significantly higher proportion of the responders, who showed a Euroclass SmB-Trnorm21norm profile (p=0.03) with a post-germinal center B cell pattern (p=0.04) in blood, suffered from enteropathies (p=0.04) as compared to non-responders. Bronchiectasis on the other hand, was exclusively found among non-responders (n=7), as was autoimmune cytopenia (n=5). Non-responders with a Euroclass SmB-21lowTrnorm profile (p=0.02), had a significantly higher prevalence of progressive antibody deficiency (p=0.048) and, at diagnosis, a higher mean serum IgM level (p=0.03), a lower mean serum IgG1 level (p=0.007), an expansion of absolute counts of cytotoxic CD8+ T-cells (p=0.033) and an increased proportion of memory CD8+ T-cells (p=0.044) in blood. CVID associated HLA markers were not detected in non-responders (p=0.03). CONCLUSION: About one-fifth of the CVID patients achieved protective antibody levels after A(H1N1) vaccination and selected clinical and immunological markers were identified that may predict a positive outcome of influenza vaccination
Energies and wave functions for a soft-core Coulomb potential
For the family of model soft Coulomb potentials represented by V(r) =
-\frac{Z}{(r^q+\beta^q)^{\frac{1}{q}}}, with the parameters
Z>0, \beta>0, q \ge 1, it is shown analytically that the potentials and
eigenvalues, E_{\nu\ell}, are monotonic in each parameter. The potential
envelope method is applied to obtain approximate analytic estimates in terms of
the known exact spectra for pure power potentials. For the case q =1, the
Asymptotic Iteration Method is used to find exact analytic results for the
eigenvalues E_{\nu\ell} and corresponding wave functions, expressed in terms of
Z and \beta. A proof is presented establishing the general concavity of the
scaled electron density near the nucleus resulting from the truncated
potentials for all q. Based on an analysis of extensive numerical calculations,
it is conjectured that the crossing between the pair of states
[(\nu,\ell),(\nu',\ell')], is given by the condition \nu'\geq (\nu+1) and \ell'
\geq (\ell+3). The significance of these results for the interaction of an
intense laser field with an atom is pointed out. Differences in the observed
level-crossing effects between the soft potentials and the hydrogen atom
confined inside an impenetrable sphere are discussed.Comment: 13 pages, 5 figures, title change, minor revision
Integrating Addiction Treatment into Primary Care Using Mobile Health Technology: Protocol for an Implementation Research Study
Healthcare reform in the United States is encouraging Federally Qualified Health Centers and other primary-care practices to integrate treatment for addiction and other behavioral health conditions into their practices. The potential of mobile health technologies to manage addiction and comorbidities such as HIV in these settings is substantial but largely untested. This paper describes a protocol to evaluate the implementation of an E-Health integrated communication technology delivered via mobile phones, called Seva, into primary-care settings. Seva is an evidence-based system of addiction treatment and recovery support for patients and real-time caseload monitoring for clinicians
Predicting death over 8 years in a prospective cohort of HIV-infected women: the Women's Interagency HIV Study.
ObjectivesPredicting mortality in middle-aged HIV-infected (HIV+) women on antiretroviral therapies (ART) is important for understanding the impact of HIV infection. Several health indices have been used to predict mortality in women with HIV infection. We evaluated: (1) an HIV biological index, Veterans Aging Cohort Study (VACS); (2) a physical index, Fried Frailty Index (FFI); and (3) a mental health index, Center for Epidemiologic Studies-Depression (CES-D). Proportional hazards regression analyses were used to predict death and included relevant covariates.DesignProspective, observational cohort.SettingMulticentre, across six sites in the USA.Participants1385 multirace/ethnic ART-experienced HIV+ women in 2005.Primary and secondary outcomesAll deaths, AIDS deaths and non-AIDS deaths up to ~8 years from baseline.ResultsIncluded together in one model, VACS Index was the dominant, significant independent predictor of all deaths within 3 years (HR=2.20, 95% CI 1.83, 2.65, χ2=69.04, p<0.0001), and later than 3 years (HR=1.55, 95% CI 1.30, 1.84, χ2=23.88, p<0.0001); followed by FFI within 3 years (HR=2.06, 95% CI 1.19, 3.57, χ2=6.73, p=0.01) and later than 3 years (HR=2.43, 95% CI 1.58, 3.75, χ2=16.18, p=0.0001). CES-D score was not independently associated with mortality.Conclusions and relevanceThis is the first simultaneous evaluation of three common health indices in HIV+ adults. Indices reflecting physical and biological ageing were associated with death
Zeno Dynamics of von Neumann Algebras
The dynamical quantum Zeno effect is studied in the context of von Neumann
algebras. We identify a localized subalgebra on which the Zeno dynamics acts by
automorphisms. The Zeno dynamics coincides with the modular dynamics of that
subalgebra, if an additional assumption is satisfied. This relates the modular
operator of that subalgebra to the modular operator of the original algebra by
a variant of the Kato-Lie-Trotter product formula.Comment: Revised version; further typos corrected; 9 pages, AMSLaTe
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