746 research outputs found

    Perceptions of genetic risk, testing, and counseling among individuals with eating disorders

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    Objective: Eating disorders develop as a result of genetic and environmental factors. Given that they are multifactorial conditions with a genetic component, they fall within the scope of practice for genetic counseling, but people with these conditions are rarely referred. The purpose of this study was to explore the perceptions of causes of eating disorders, recurrence risk, and interest in genetic counseling and testing among individuals with eating disorders. Method: An online survey comprising both multiple choice and free form text questions, vignettes about genetic counseling, and the ED100K (validated eating disorder diagnostic questionnaire) was shared via support organizations and prominent bloggers in the eating disorders community to recruit individuals with a personal history of an eating disorder from November 2018 to February 2019. Results: In total, 107 participants completed the survey. They perceived that both experiences and genetics were important factors in the development of their eating disorder. All responding participants overestimated the risk for recurrence of eating disorders in children, often by a large margin, and a notable minority reported that their experience with an eating disorder had a negative influence on their childbearing decisions. After imagined experience of genetic counseling, participants reported significantly decreased feelings of stigma, shame, and guilt. Most participants expressed interest in genetic counseling; fewer were interested in genetic testing. Discussion: Genetic counseling may benefit individuals with eating disorders by providing accurate recurrence risk information and reducing feelings of guilt, stigma, and shame, which may in turn encourage earlier support seeking and recovery

    L- and P-selectin and CD11/CD18 in intracapillary neutrophil sequestration in rabbit lungs

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    Infusion of complement fragments induces rapid sequestration of neutrophils within pulmonary capillaries. This study examined the mechanisms through which this sequestration occurs, as well as the effect of complement fragments on the expression of L-selectin and CD11/CD18 using ultrastructural immunohistochemistry. Studies using anti-P-selectin antibodies, fucoidin, L- selectin-depleted neutrophils, and anti-CD18 antibodies showed that selectins and CD18 were not required for neutrophil sequestration. However, maintaining the sequestered neutrophils within the pulmonary capillaries required both L- selectin and CD11/CD18. Neutrophils in the pulmonary capillaries of rabbits given complement fragments expressed 72% less L-selectin and 98% more CD11/CD18 than did those in rabbits given saline. Shedding of L-selectin occurred preferentially from the microvillar processes of the plasma membrane rather than from the fiat intervening regions. About 28% of L-selectin still remained on intracapillary neutrophil membranes after 15 min and was likely available for binding. Shedding of L-selectin appeared slower in vivo than in vitro. These studies indicate that neutrophil sequestration induced by complement fragments requires at least two sequential steps, one that does not require recognized adhesion molecules followed by a second that requires L-selectin and CD11/CD18

    Lymphocyte accumulation during Pseudomonas aeruginosa-induced pneumonia in rodents does not require CD11a and intercellular adhesion molecule-1.

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    During Pseudomonas aeruginosa-induced pneumonia in rodents, the acute infiltrate of neutrophils is followed by accumulation of lymphocytes in the perivascular connective tissue. The roles of the adhesion molecules CD11a/CD18 and intercellular adhesion molecule-1 (ICAM-1) in this accumulation of lymphocytes were investigated. The numbers of lymphocytes in P. aeruginosa-induced pneumonia were compared in animals treated with blocking antibodies to either CD11a, ICAM-1, IgG, or no antibody. In other experiments, the lymphocyte accumulation during P. aeruginosa-induced pneumonia in ICAM-1 mutant mice was compared with that in wild-type mice. In rats, both a murine anti-rat CD11a antibody and nonspecific murine IgG partially inhibited the lymphocyte accumulation by 30 to 40% compared with animals that received no antibodies. In mice, blocking antibodies to either CD11a or ICAM-1 did not decrease the lymphocyte accumulation compared with mice given IgG or no antibody. Further, there was no attenuation of the lymphocyte accumulation induced by P. aeruginosa in the ICAM-1 mutant mice compared with wild-type mice, either in the total number of lymphocytes or the number of CD4+, CD8+, or B cells. We conclude that neither CD11a/CD18 nor ICAM-1 are required for lymphocyte accumulation during P. aeruginosa-induced pneumonia in rodents. The partial inhibition of the lymphocyte accumulation in both the anti-CD11a- and IgG-treated rats may be due to nonspecific effects of foreign proteins on cellular functions

    Large-scale collective motion of RFGC galaxies

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    We processed the data about radial velocities and HI linewidths for 1678 flat edge-on spirals from the Revised Flat Galaxy Catalogue. We obtained the parameters of the multipole components of large-scale velocity field of collective non-Hubble galaxy motion as well as the parameters of the generalized Tully-Fisher relationship in the "HI line width - linear diameter" version. All the calculations were performed independently in the framework of three models, where the multipole decomposition of the galaxy velocity field was limited to a dipole, quadrupole and octopole terms respectively. We showed that both the quadrupole and the octopole components are statistically significant. On the basis of the compiled list of peculiar velocities of 1623 galaxies we obtained the estimations of cosmological parameters Omega_m and sigma_8. This estimation is obtained in both graphical form and as a constraint of the value S_8=sigma_8(Omega_m/0.3)^0.35 = 0.91 +/- 0.05.Comment: Accepted for publication in Astrophysics and Space Scienc

    Measuring the Neutron Lifetime Using Magnetically Trapped Neutrons

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    The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In previous work, we successfully demonstrated the trapping of ultracold neutrons (UCN) in a conservative potential magnetic trap. A major upgrade of the apparatus is nearing completion at the National Institute of Standards and Technology Center for Neutron Research (NCNR). In our approach, a beam of 0.89 nm neutrons is incident on a superfluid 4He target within the minimum field region of an Ioffe-type magnetic trap. A fraction of the neutrons is downscattered in the helium to energies <200 neV, and those in the appropriate spin state become trapped. The inverse process is suppressed by the low phonon density of helium at temperatures less than 200 mK, allowing the neutron to travel undisturbed. When the neutron decays the energetic electron ionizes the helium, producing scintillation light that is detected using photomultiplier tubes. Statistical limitations of the previous apparatus will be alleviated by significant increases in field strength and trap volume resulting in twenty times more trapped neutrons.Comment: 5 pages, 5 figure

    Infectious susceptibility and severe deficiency of leukocyte rolling and recruitment in E-selectin and P-selectin double mutant mice

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    During the initial phase of the inflammatory response, leukocytes marginate and roll along the endothelial surface, a process mediated largely by the selectins and their ligands. Mice with mutations in individual selectins show no spontaneous disease and have mild or negligible deficiencies of inflammatory responses. In contrast, we find that mice with null mutations in both endothelial selectins (P and E) develop a phenotype of leukocyte adhesion deficiency characterized by mucocutaneous infections, plasma cell proliferation, hypergammaglobulinemia, severe deficiencies of leukocyte rolling in cremaster venules with or without addition of TNF-α, and an absence of neutrophil emigration at 4 h in response to intraperitoneal Streptococcus pneumoniae peritonitis. These mice provide strong evidence for the functional importance of selectins in vivo

    New Insights into White-Light Flare Emission from Radiative-Hydrodynamic Modeling of a Chromospheric Condensation

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    (abridged) The heating mechanism at high densities during M dwarf flares is poorly understood. Spectra of M dwarf flares in the optical and near-ultraviolet wavelength regimes have revealed three continuum components during the impulsive phase: 1) an energetically dominant blackbody component with a color temperature of T \sim 10,000 K in the blue-optical, 2) a smaller amount of Balmer continuum emission in the near-ultraviolet at lambda << 3646 Angstroms and 3) an apparent pseudo-continuum of blended high-order Balmer lines. These properties are not reproduced by models that employ a typical "solar-type" flare heating level in nonthermal electrons, and therefore our understanding of these spectra is limited to a phenomenological interpretation. We present a new 1D radiative-hydrodynamic model of an M dwarf flare from precipitating nonthermal electrons with a large energy flux of 101310^{13} erg cm2^{-2} s1^{-1}. The simulation produces bright continuum emission from a dense, hot chromospheric condensation. For the first time, the observed color temperature and Balmer jump ratio are produced self-consistently in a radiative-hydrodynamic flare model. We find that a T \sim 10,000 K blackbody-like continuum component and a small Balmer jump ratio result from optically thick Balmer and Paschen recombination radiation, and thus the properties of the flux spectrum are caused by blue light escaping over a larger physical depth range compared to red and near-ultraviolet light. To model the near-ultraviolet pseudo-continuum previously attributed to overlapping Balmer lines, we include the extra Balmer continuum opacity from Landau-Zener transitions that result from merged, high order energy levels of hydrogen in a dense, partially ionized atmosphere. This reveals a new diagnostic of ambient charge density in the densest regions of the atmosphere that are heated during dMe and solar flares.Comment: 50 pages, 2 tables, 13 figures. Accepted for publication in the Solar Physics Topical Issue, "Solar and Stellar Flares". Version 2 (June 22, 2015): updated to include comments by Guest Editor. The final publication is available at Springer via http://dx.doi.org/10.1007/s11207-015-0708-

    Nonlinear effects in resonant layers in solar and space plasmas

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    The present paper reviews recent advances in the theory of nonlinear driven magnetohydrodynamic (MHD) waves in slow and Alfven resonant layers. Simple estimations show that in the vicinity of resonant positions the amplitude of variables can grow over the threshold where linear descriptions are valid. Using the method of matched asymptotic expansions, governing equations of dynamics inside the dissipative layer and jump conditions across the dissipative layers are derived. These relations are essential when studying the efficiency of resonant absorption. Nonlinearity in dissipative layers can generate new effects, such as mean flows, which can have serious implications on the stability and efficiency of the resonance

    D* Production in Deep Inelastic Scattering at HERA

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    This paper presents measurements of D^{*\pm} production in deep inelastic scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The data have been taken with the ZEUS detector at HERA. The decay channel D+(D0Kπ+)π+D^{*+}\to (D^0 \to K^- \pi^+) \pi^+ (+ c.c.) has been used in the study. The e+pe^+p cross section for inclusive D^{*\pm} production with 5<Q2<100GeV25<Q^2<100 GeV^2 and y<0.7y<0.7 is 5.3 \pms 1.0 \pms 0.8 nb in the kinematic region {1.3<pT(D±)<9.01.3<p_T(D^{*\pm})<9.0 GeV and η(D±)<1.5| \eta(D^{*\pm}) |<1.5}. Differential cross sections as functions of p_T(D^{*\pm}), η(D±),W\eta(D^{*\pm}), W and Q2Q^2 are compared with next-to-leading order QCD calculations based on the photon-gluon fusion production mechanism. After an extrapolation of the cross section to the full kinematic region in p_T(D^{*\pm}) and η\eta(D^{*\pm}), the charm contribution F2ccˉ(x,Q2)F_2^{c\bar{c}}(x,Q^2) to the proton structure function is determined for Bjorken xx between 2 \cdot 104^{-4} and 5 \cdot 103^{-3}.Comment: 17 pages including 4 figure
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