Hemoptysis Complicating Mitral Stenosis: Case report with attention to differential diagnosis and a review of the literature

The differential diagnosis of hemoptysis in patients with mitral stenosis includes many primary pulmonary problems besides those peculiar to mitral stenosis. We describe the case of a 40-year-old woman with a 40-pack-year smoking history whose presenting symptom of hemoptysis was wrongly ascribed to pulmonary embolus and infarction, based on a presumably positive angiogram, and to chronic bronchitis, based on endoscopic findings at fiberoptic bronchoscopy, as provided by the referring physician. The features differentiating between cardiac and primary pulmonary disease are described, and the pathophysiology of hemoptysis in mitral stenosis is reviewed. In a case like the one we describe, hemoptysis is an important manifestation of severe valvular stenosis, and surgical intervention, i.e., mitral commissurotomy or mitral valve replacement, should be considered

Signatures of Electronic Correlations in Optical Properties of LaFeAsO1−x_{1-x}Fx_x

Spectroscopic ellipsometry is used to determine the dielectric function of the superconducting LaFeAsO$_{0.9}$F$_{0.1}$ ($T_c$ = 27 K) and undoped LaFeAsO polycrystalline samples in the wide range 0.01-6.5 eV at temperatures 10 $\leq T \leq$ 350 K. The free charge carrier response in both samples is heavily damped with the effective carrier density as low as 0.040$\pm$0.005 electrons per unit cell. The spectral weight transfer in the undoped LaFeAsO associated with opening of the pseudogap at about 0.65 eV is restricted at energies below 2 eV. The spectra of superconducting LaFeAsO$_{0.9}$F$_{0.1}$ reveal a significant transfer of the spectral weight to a broad optical band above 4 eV with increasing temperature. Our data may imply that the electronic states near the Fermi surface are strongly renormalized due to electron-phonon and/or electron-electron interactions.Comment: 4 pages, 4 figures, units in Fig.2 adde

Ferromagnetism and Lattice Distortions in the Perovskite YTiO3_3

The thermodynamic properties of the ferromagnetic perovskite YTiO$_3$ are investigated by thermal expansion, magnetostriction, specific heat, and magnetization measurements. The low-temperature spin-wave contribution to the specific heat, as well as an Arrott plot of the magnetization in the vicinity of the Curie temperature $T_C\simeq27$ K, are consistent with a three-dimensional Heisenberg model of ferromagnetism. However, a magnetic contribution to the thermal expansion persists well above $T_C$, which contrasts with typical three-dimensional Heisenberg ferromagnets, as shown by a comparison with the corresponding model system EuS. The pressure dependences of $T_C$ and of the spontaneous moment $M_s$ are extracted using thermodynamic relationships. They indicate that ferromagnetism is strengthened by uniaxial pressures $\mathbf{p}\parallel \mathbf{a}$ and is weakened by uniaxial pressures $\mathbf{p}\parallel \mathbf{b},\mathbf{c}$ and hydrostatic pressure. Our results show that the distortion along the $a$- and $b$-axes is further increased by the magnetic transition, confirming that ferromagnetism is favored by a large GdFeO$_3$-type distortion. The c-axis results however do not fit into this simple picture, which may be explained by an additional magnetoelastic effect, possibly related to a Jahn-Teller distortion.Comment: 12 pages, 13 figure

RegenBase: a knowledge base of spinal cord injury biology for translational research.

Spinal cord injury (SCI) research is a data-rich field that aims to identify the biological mechanisms resulting in loss of function and mobility after SCI, as well as develop therapies that promote recovery after injury. SCI experimental methods, data and domain knowledge are locked in the largely unstructured text of scientific publications, making large scale integration with existing bioinformatics resources and subsequent analysis infeasible. The lack of standard reporting for experiment variables and results also makes experiment replicability a significant challenge. To address these challenges, we have developed RegenBase, a knowledge base of SCI biology. RegenBase integrates curated literature-sourced facts and experimental details, raw assay data profiling the effect of compounds on enzyme activity and cell growth, and structured SCI domain knowledge in the form of the first ontology for SCI, using Semantic Web representation languages and frameworks. RegenBase uses consistent identifier schemes and data representations that enable automated linking among RegenBase statements and also to other biological databases and electronic resources. By querying RegenBase, we have identified novel biological hypotheses linking the effects of perturbagens to observed behavioral outcomes after SCI. RegenBase is publicly available for browsing, querying and download.Database URL:http://regenbase.org

Reactions of O,O-dialkyldithiophosphoric acids with non-activated α-olefins

Electrophilic addition reactions of O,O-dialkyldithiophosphoric acids to non-activated α-olefins proceeding in accordance with the Markovnikov's rule were studied. In the absence of a catalyst these reactions occur very slowly to give the products in low yields, while Lewis acid as a catalyst can greatly accelerate the reaction and increase the conversion in the Ad E-processes. A similar acceleration of the addition processes and an increase in the reaction product yield occur at the action of ultrasound on the reaction medium. © 2012 Pleiades Publishing, Ltd.

Superconductivity mediated by a soft phonon mode: specific heat, resistivity, thermal expansion and magnetization of YB6

The superconductor YB6 has the second highest critical temperature Tc among the boride family MBn. We report measurements of the specific heat, resistivity, magnetic susceptibility and thermal expansion from 2 to 300 K, using a single crystal with Tc = 7.2 K. The superconducting gap is characteristic of medium-strong coupling. The specific heat, resistivity and expansivity curves are deconvolved to yield approximations of the phonon density of states, the spectral electron-phonon scattering function and the phonon density of states weighted by the frequency-dependent Grueneisen parameter respectively. Lattice vibrations extend to high frequencies >100 meV, but a dominant Einstein-like mode at ~8 meV, associated with the vibrations of yttrium ions in oversized boron cages, appears to provide most of the superconducting coupling and gives rise to an unusual temperature behavior of several observable quantities. A surface critical field Hc3 is also observed.Comment: 29 pages, 5 tables, 17 figures. Accepted for publication in Phys. Rev.

Southeast Asian refugee children: Self-esteem as a predictor of depression and scholastic achievement in the U.S.

The eruption of conflicts and war in this century has led to new masses of refugees and displaced persons. Globally, host countries will continue to confront issues of how to ensure the successful adaptation of refugees who typically are women and children. The United States received three major waves of Southeast Asian (SEA) refugees during the past twenty-five years. One million SEA refugees arrived in the past decade; the majority were children and adolescents. Today, there is still a lack of understanding surrounding mental health issues and their relationship to children\u27s violence experience. We know that SEA refugee children suffered violence during the war in Southeast Asia, their escape from homelands, in camps of asylum and in the U.S. Although researchers have examined the relationship of violence with depression and post-traumatic stress disorder in refugee children, the findings have been unclear and sometimes conflictual in their relationship to scholastic achievement. In the U.S., healthy self-esteem is recognized as an important component of mental health and academic success, while low self-esteem is associated with depression and academic failure. In general, self-esteem and measures of self-esteem have not been studied cross-culturally. The authors report the findings of a measure of self-esteem, depression and academic achievement in a convenience sample of 237 Southeast Asian refugee children aged 6 to 17 years of age in the U.S. Internationally, nurses who assess the mental health of refugee children and design interventions to assist in their adaptation, will want to have an understanding of mental health issues cross-culturally