Background: Student-run free clinics are critical for medical education and medical care of underserved populations. This paper explores the feasibility of establishing ethical preventative health services at student-run free clinics such as the Rochester Education and Advocacy for Community Health (REACH) Clinic, affiliated with the Mayo Clinic Alix School of Medicine. Our analysis discusses the challenges and ethical considerations of providing preventative healthcare in student-run clinics.
View Article and Find Full Text PDFDifferences in characteristics and outcomes between incidental and symptomatic presentations of Large B-Cell Lymphoma.
View Article and Find Full Text PDFHerpesvirus entry requires the coordinated action of at least four viral glycoproteins. Virus-specific binding to a cellular receptor triggers a membrane fusion cascade involving the conserved gH/gL complex and gB. Although gB is the genuine herpesvirus fusogen, it requires gH/gL for fusion, but how activation occurs is still unclear.
View Article and Find Full Text PDFWe introduce a new stress dilatometer with exactly the same size and mass as the world's smallest miniature capacitance dilatometer (height × width × depth = 15 × 14 × 15 mm3, mass: 12 g). To develop this new device, only a single part of the most recently developed mini-dilatometer, the so-called "body," needs to be replaced. Therefore, the new mini-dilatometer with an interchangeable body can be used for high-resolution measurements of thermal expansion and magnetostriction with and without large stress.
View Article and Find Full Text PDFIntermetallic compounds containing f-electron elements have been prototypical materials for investigating strong electron correlations and quantum criticality (QC). Their heavy fermion ground state evoked by the magnetic f-electrons is susceptible to the onset of quantum phases, such as magnetism or superconductivity, due to the enhanced effective mass (m) and a corresponding decrease of the Fermi temperature. However, the presence of f-electron valence fluctuations to a non-magnetic state is regarded an anathema to QC, as it usually generates a paramagnetic Fermi-liquid state with quasiparticles of moderate m.
View Article and Find Full Text PDFNMR spectroscopy allows the study of biomolecules in close-to-native conditions. Structural information can be inferred from the NMR spectra when an assignment is available. Protein assignment is usually a time-consuming task, being specially challenging in the case of large, supramolecular systems.
View Article and Find Full Text PDFMaterials with multiple superconducting phases are rare. Here, we report the discovery of two-phase unconventional superconductivity in CeRhAs Using thermodynamic probes, we establish that the superconducting critical field of its high-field phase is as high as 14 tesla, even though the transition temperature is only 0.26 kelvin.
View Article and Find Full Text PDFBackground: Motion analysis is commonly used to evaluate joint kinetics in children with cerebral palsy who exhibit gait disorders. However, one cannot readily infer muscle-tendon forces from joint kinetics. This study investigates the use of shear wave tensiometry to characterize Achilles and patellar tendon forces during gait.
View Article and Find Full Text PDFThe quantum Hall effect (QHE) is traditionally considered to be a purely two-dimensional (2D) phenomenon. Recently, however, a three-dimensional (3D) version of the QHE was reported in the Dirac semimetal ZrTe. It was proposed to arise from a magnetic-field-driven Fermi surface instability, transforming the original 3D electron system into a stack of 2D sheets.
View Article and Find Full Text PDFLead-free double perovskites have great potential as stable and nontoxic optoelectronic materials. Recently, Cs AgBiBr has emerged as a promising material, with suboptimal photon-to-charge carrier conversion efficiency, yet well suited for high-energy photon-detection applications. Here, the optoelectronic and structural properties of pure Cs AgBiBr and alkali-metal-substituted (Cs Y ) AgBiBr (Y: Rb , K , Na ; x = 0.
View Article and Find Full Text PDFComplex and correlated quantum systems with promise for new functionality often involve entwined electronic degrees of freedom. In such materials, highly unusual properties emerge and could be the result of electron localization. Here, a cubic heavy fermion metal governed by spins and orbitals is chosen as a model system for this physics.
View Article and Find Full Text PDFWe report on negative thermal expansion (NTE) in the high-field, half-magnetization plateau phase of the frustrated magnetic insulator CdCr_{2}O_{4}. Using dilatometry, we precisely map the phase diagram at fields of up to 30 T and identify a strong NTE associated with the collinear half-magnetization plateau for B>27 T. The resulting phase diagram is compared with a microscopic theory for spin-lattice coupling, and the origin of the NTE is identified as a large negative change in magnetization with temperature, coming from a nearly localized band of spin excitations in the plateau phase.
View Article and Find Full Text PDFThe extraordinary properties of lead-halide perovskite materials have spurred intense research, as they have a realistic perspective to play an important role in future photovoltaic devices. It is known that these materials undergo a number of structural phase transitions as a function of temperature that markedly alter their optical and electronic properties. The precise phase transition temperature and exact crystal structure in each phase, however, are controversially discussed in the literature.
View Article and Find Full Text PDFThe study of organogenesis, tissue-homeostasis and regeneration requires the precise assessment of in vivo cell proliferation. To this end a host of methods have been developed to detect and quantify DNA synthesis in proliferating cells. These include cell labeling with various nucleotide analogues and fluorescence reporter-based animal models with each method presenting its idiosyncratic shortcomings.
View Article and Find Full Text PDFA ferromagnetic quantum critical point is thought not to exist in two- and three-dimensional metallic systems yet is realized in the Kondo lattice compound YbNi_{4}(P,As)_{2}, possibly due to its one-dimensionality. It is crucial to investigate the dimensionality of the Fermi surface of YbNi_{4}P_{2} experimentally, but common probes such as angle-resolved photoemission spectroscopy and quantum oscillation measurements are lacking. Here, we study the magnetic-field dependence of transport and thermodynamic properties of YbNi_{4}P_{2}.
View Article and Find Full Text PDFWhen a magnetic field confines the carriers of a Fermi sea to their lowest Landau level, electron-electron interactions are expected to play a significant role in determining the electronic ground state. Graphite is known to host a sequence of magnetic field-induced states driven by such interactions. Three decades after their discovery, thermodynamic signatures of these instabilities are still elusive.
View Article and Find Full Text PDFThe basic two-step terminal differentiation model of the medullary thymic epithelial cell (mTEC) lineage from immature MHC class II (MHCII) to mature MHCII mTECs has recently been extended to include a third stage, namely the post-Aire MHCII subset as identified by lineage-tracing models. However, a suitable surface marker distinguishing the phenotypically overlapping pre- from the post-Aire MHCII stage has been lacking. In this study, we introduce the lectin agglutinin (TPA) as a novel cell surface marker that allows for such delineation.
View Article and Find Full Text PDFFor the characterization of novel quantum phases of matter, it is often required to study materials under multi-extreme conditions, in particular down to very low temperatures and in very high magnetic fields. We developed the world's smallest high-resolution capacitive dilatometer suitable for temperatures down to 10 mK and usage in high magnetic fields up to 37.5 T.
View Article and Find Full Text PDFThermal expansion and magnetostriction are directional dependent thermodynamic quantities. For the characterization of novel quantum phases of matter, it is required to study materials under multi-extreme conditions, in particular, down to very low temperatures, in very high magnetic fields or under high pressure. We developed a miniaturized capacitive dilatometer suitable for temperatures down to 20 mK and usage in high magnetic fields, which exerts a large spring force between 40 to 75 N on the sample.
View Article and Find Full Text PDFExpression of tissue-restricted self antigens (TRAs) in medullary thymic epithelial cells (mTECs) is essential for the induction of self-tolerance and prevents autoimmunity, with each TRA being expressed in only a few mTECs. How this process is regulated in single mTECs and is coordinated at the population level, such that the varied single-cell patterns add up to faithfully represent TRAs, is poorly understood. Here we used single-cell RNA sequencing and obtained evidence of numerous recurring TRA-co-expression patterns, each present in only a subset of mTECs.
View Article and Find Full Text PDFSmFeO3 has attracted considerable attention very recently due to its reported multiferroic properties above room temperature. We have performed powder and single crystal neutron diffraction as well as complementary polarization dependent soft X-ray absorption spectroscopy measurements on floating-zone grown SmFeO3 single crystals in order to determine its magnetic structure. We found a k=0 G-type collinear antiferromagnetic structure that is not compatible with inverse Dzyaloshinskii-Moriya interaction driven ferroelectricity.
View Article and Find Full Text PDFDefensins protect human barriers from commensal and pathogenic microorganisms. Human α-defensin 6 (HD-6) is produced exclusively by small intestinal Paneth cells but, in contrast to other antimicrobial peptides (AMPs) for HD-6, no direct antibacterial killing activity has been detected so far. Herein, we systematically tested how environmental factors, like pH and reducing conditions, affect antimicrobial activity of different defensins against anaerobic bacteria of the human intestinal microbiota.
View Article and Find Full Text PDFElectron-like carriers in bismuth are described by the Dirac Hamiltonian, with a band mass becoming a thousandth of the bare electron mass along one crystalline axis. The existence of three anisotropic valleys offers electrons an additional degree of freedom, a subject of recent attention. Here, we map the Landau spectrum by angle-resolved magnetostriction, and quantify the carrier number in each valley: while the electron valleys keep identical spectra, they substantially differ in their density of states at the Fermi level.
View Article and Find Full Text PDFAntimicrob Agents Chemother
October 2013
The human intestinal tract is highly colonized by a vast number of microorganisms. Despite this permanent challenge, infections remain rare, due to a very effective barrier defense system. Essential effectors of this system are antimicrobial peptides and proteins (AMPs), which are secreted by intestinal epithelial and lymphoid cells, balance the gut microbial community, and prevent the translocation of microorganisms.
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