Scaling Study and Thermodynamic Properties of the cubic Helimagnet FeGe

The critical behavior of the cubic helimagnet FeGe was obtained from isothermal magnetization data in very close vicinity of the ordering temperature. A thorough and consistent scaling analysis of these data revealed the critical exponents $\beta=0.368$, $\gamma=1.382$, and $\delta=4.787$. The anomaly in the specific heat associated with the magnetic ordering can be well described by the critical exponent $\alpha=-0.133$. The values of these exponents corroborate that the magnetic phase transition in FeGe belongs to the isotropic 3D-Heisenberg universality class. The specific heat data are well described by ab initio phonon calculations and confirm the localized character of the magnetic moments.Comment: 10 pages, 8 figure

Versatile two-dimensional potentials for ultra-cold atoms

We propose and investigate a technique for generating smooth two-dimensional potentials for ultra-cold atoms based on the rapid scanning of a far-detuned laser beam using a two-dimensional acousto-optical modulator (AOM). We demonstrate the implementation of a feed-forward mechanism for fast and accurate control of the spatial intensity of the laser beam, resulting in improved homogeneity for the atom trap. This technique could be used to generate a smooth toroidal trap that would be useful for static and dynamic experiments on superfluidity and persistent currents with ultra-cold atoms.Comment: 8 pages, 5 figure

Determinants of health after hospital discharge: rationale and design of the Vanderbilt Inpatient Cohort Study (VICS)

BACKGROUND: The period following hospital discharge is a vulnerable time for patients when errors and poorly coordinated care are common. Suboptimal care transitions for patients admitted with cardiovascular conditions can contribute to readmission and other adverse health outcomes. Little research has examined the role of health literacy and other social determinants of health in predicting post-discharge outcomes. METHODS: The Vanderbilt Inpatient Cohort Study (VICS), funded by the National Institutes of Health, is a prospective longitudinal study of 3,000 patients hospitalized with acute coronary syndromes or acute decompensated heart failure. Enrollment began in October 2011 and is planned through October 2015. During hospitalization, a set of validated demographic, cognitive, psychological, social, behavioral, and functional measures are administered, and health status and comorbidities are assessed. Patients are interviewed by phone during the first week after discharge to assess the quality of hospital discharge, communication, and initial medication management. At approximately 30 and 90 days post-discharge, interviewers collect additional data on medication adherence, social support, functional status, quality of life, and health care utilization. Mortality will be determined with up to 3.5 years follow-up. Statistical models will examine hypothesized relationships of health literacy and other social determinants on medication management, functional status, quality of life, utilization, and mortality. In this paper, we describe recruitment, eligibility, follow-up, data collection, and analysis plans for VICS, as well as characteristics of the accruing patient cohort. DISCUSSION: This research will enhance understanding of how health literacy and other patient factors affect the quality of care transitions and outcomes after hospitalization. Findings will help inform the design of interventions to improve care transitions and post-discharge outcomes

Tools to Detect Delirium Superimposed on Dementia:A Systematic Review

BACKGROUND: Delirium commonly occurs in patients with dementia. Though several tools for detecting delirium exist, it is unclear which are valid in patients with delirium superimposed on dementia. OBJECTIVES: Identify valid tools to diagnose delirium superimposed on dementia DESIGN: We performed a systematic review of studies of delirium tools, which explicitly included patients with dementia. SETTING: In-hospital patients PARTICIPANTS: Studies were included if delirium assessment tools were validated against standard criteria, and the presence of dementia was assessed according to standard criteria that used validated instruments. MEASUREMENTS: PubMed, Embase, and Web of Science databases were searched for articles in English published between January 1960 and January 2012. RESULTS: Nine studies fulfilled the selection criteria. Of the total of 1569 patients, 401 had dementia, and 50 had delirium superimposed on dementia. Six delirium tools were evaluated. One studyusing the Confusion Assessment Method (CAM) with 85% patients with dementia showed a high specificity (96–100%) and moderate sensitivity (77%).Two intensive care unit studies that used the CAM for the Intensive Care Unit (CAM-ICU) ICU reported 100% sensitivity and specificity for delirium among 23 dementia patients. One study using electroencephalography reported a sensitivity of 67% and a specificity of 91% among a population with 100% prevalence of dementia. No studies examined potential effects of dementia severity or subtype upon diagnostic accuracy. CONCLUSIONS: The evidence base on tools for detection of delirium superimposed on dementia is limited, although some existing tools show promise. Further studies of existing or refined tools with larger samples and more detailed characterization of dementia are now required to address the identification of delirium superimposed on dementia

Studies of Impurity-Doping Effects and NMR Measurement5s of La1111 and/or Nd 1111 Fe-Pnictide Superconductors

Measurements of the electrical resistivities, Hall coefficients, thermoelectric powers, electronic specific heat coefficients have been carried out for samples of LnFe1-yMyAsO1-xFx (Ln=La, Nd; M=Co, Mn; x=0.11) obtained by M atom dopings to the superconducting LnFeAsO1-xFx (Ln1111) system. The NMR longitudinal relaxation rates 1/T1 have also been measured for samples of LaFe1-yCoyAsO1-xFx with various x values. Co atoms doped to the superconducting LnFeAsO1-xFx are nonmagnetic, and the Tc-suppression by the Co atoms has been found to be too weak to understand by the pair breaking effect expected for the S+- superconducting symmetry proposed as the most probable one for the system. It throws a serious doubt whether the symmetry is realized in this system. Instead of the pair breaking, two mechanisms of the Tc-suppression by the doped impurities have been found: One is the electron localization, which appears when the sheet resistance exceeds h/4e2=6.45 kohm, and another is the disappearance or reduction of the hole-Fermi-surfaces around the gamma point in the reciprocal space. The latter mechanism has been observed, when the electron number increases with increasing Co-doping level and the system changes from an anomalous metal to an ordinary one. On the two distinct T dependences of 1/T1 of LaFeAsO1-xFx, 1/T1 T6 reported by our group in the T region from Tc to ~0.4 Tc for samples with the highest Tc values with varying x, and 1/T1 T2.5-3.0 observed by many groups in the almost entire T region studied below Tc, we discuss what the origin of the difference is, and show that, at least, the T2.5-3.0-like dependence of 1/T1 cannot be considered as the experimental evidence for the S+- symmetry of the order parameter.Comment: 11 pages, 14 figures, accepted for publication in J. Phys. Soc. Jpn., Fig. 14 adde

Lack of chart reminder effectiveness on family medicine resident JNC-VI and NCEP III guideline knowledge and attitudes

BACKGROUND: The literature demonstrates that medical residents and practicing physicians have an attitudinal-behavioral discordance concerning their positive attitudes towards clinical practice guidelines (CPG), and the implementation of these guidelines into clinical practice patterns. METHODS: A pilot study was performed to determine if change in a previously identified CPG compliance factor (accessibility) would produce a significant increase in family medicine resident knowledge and attitude toward the guidelines. The primary study intervention involved placing a summary of the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) and the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (NCEP III) CPGs in all patient (>18 yr.) charts for a period of three months. The JNC VI and NCEP III CPGs were also distributed to each Wayne State family medicine resident, and a copy of each CPG was placed in the preceptor's area of the involved clinics. Identical pre- and post- intervention questionnaires were administered to all residents concerning CPG knowledge and attitude. RESULTS: Post-intervention analysis failed to demonstrate a significant difference in CPG knowledge. A stastically significant post-intervention difference was found in only on attitude question. The barriers to CPG compliance were identified as 1) lack of CPG instruction; 2) lack of critical appraisal ability; 3) insufficient time; 4) lack of CPG accessibility; and 5) lack of faculty modeling. CONCLUSION: This study demonstrated no significant post intervention changes in CPG knowledge, and only one question that reflected attitude change. Wider resident access to dedicated clinic time, increased faculty modeling, and the implementation of an electronic record/reminder system that uses a team-based approach are compliance factors that should be considered for further investigation. The interpretation of CPG non-compliance will benefit from a causal matrix focused on physician knowledge, attitudes, and behavior. Recent findings in resident knowledge-behavior discordance may direct the future investigation of physician CPG non-compliance away from generalized barrier research, and toward the development of information that maximizes the sense of individual practitioner urgency and certainty

An early European experience with transapical off-pump mitral valve repair with NeoChord implantation

OBJECTIVES: Transapical off-pump NeoChord repair is a novel minimally invasive surgical procedure to treat degenerative mitral valve regurgitation. The aim was to evaluate 1-year clinical results of the NeoChord procedure in a consecutive cohort of patients. METHODS: Between February 2013 and July 2016, 213 patients were enrolled in the NeoChord Independent International Registry. All patients presented severe mitral regurgitation due to flail/prolapse of 1 or both leaflets, and they all completed postoperative echocardiographic assessment up to 1 year. We identified the primary end point as composed of procedural success, freedom from mortality, stroke, reintervention, recurrence of severe mitral regurgitation, rehospitalization and decrease of at least 1 New York Heart Association functional class at 1-year follow-up. We also compared outcomes according to the anatomical classification (Type A: isolated central posterior leaflet disease; Type B: posterior multisegment disease; Type C: anterior, bileaflet, paracommissural disease with/without leaflet/annular calcifications). RESULTS: The median age was 68 years (interquartile range 56-77), and the median EuroSCORE II was 1.05% (interquartile range 0.67-1.76). The number of Type A, B and C patients was 82 (38.5%), 98 (46%) and 33 (15.5%), respectively. Procedural success was achieved in 206 (96.7%) patients. At 1-year follow-up, overall survival was 98 ± 1%. Composite end point was achieved in 84 ± 2.5% for the overall population and 94 ± 2.6%, 82.6 ± 3.8% and 63.6 ± 8.4% in Type A, Type B and Type C patients, respectively (P < 0.0001). CONCLUSIONS: These results demonstrate that the NeoChord procedure is safe, effective and reproducible. Clinical and echocardiographic efficacy is maintained up to 1 year with significant differences among the anatomical groups. Specific anatomical selection criteria are necessary to achieve stable results

Исследование оптических свойств реконденсатов CCl4, полученных методом криоматричной изоляции

Объектом исследования являются тетрахлорметаан (четырёххлористый углерод) CCl4, которые были получены методом газофазной конденсации с матричным газом в различных концентрационных соотношениях с азотом и аргоном. Целью работы является изучение процессов формирования и эволюции свойств тонких пленок реконденсатов молекул фреона CCl4, образующихся в результате структурно-фазовых превращений и релаксационных процессов в твердых растворах исследуемых веществ при низких и сверхнизких температурах. Для достижения, были поставлены такие задачи: определить взаимосвязь между условиями криоосаждения и свойствами образующейся криоконденсированной пленки, а также изучить особенности криоконденсации тетрахлорометана и определить температуру стеклования образованных при низких температурах криопленок.The object of the study is carbon tetrachloride, which were obtained by gas-phase condensation with matrix gas in various concentration ratios with nitrogen and argon. The aim of the work is to study the processes of formation and evolution of the properties of thin films of recondensates of CCl4 freon molecules formed as a result of structural-phase transformations and relaxation processes in solid solutions of the studied substances at low and ultra-low temperatures. To achieve this, the following tasks were set: to determine the relationship between the conditions of cryopreservation and the properties of the resulting cryocondensated film, as well as to study the features of cryocondensation of tetrachloromethane and to determine the glass transition temperature of cryofilms formed

Pressure effects on the electron-doped high Tc superconductor BaFe(2-x)Co(x)As(2)

Application of pressures or electron-doping through Co substitution into Fe sites transforms the itinerant antiferromagnet BaFe(2)As(2) into a superconductor with the Tc exceeding 20K. We carried out systematic transport measurements of BaFe(2-x)Co(x)As(2) superconductors in pressures up to 2.5GPa, and elucidate the interplay between the effects of electron-doping and pressures. For the underdoped sample with nominal composition x = 0.08, application of pressure strongly suppresses a magnetic instability while enhancing Tc by nearly a factor of two from 11K to 21K. In contrast, the optimally doped x=0.20 sample shows very little enhancement of Tc=22K under applied pressure. Our results strongly suggest that the proximity to a magnetic instability is the key to the mechanism of superconductivity in iron-pnictides.Comment: 5 figure

Striking Zn impurity effect on the Fe-based superconductor BaFe1.87Co0.13As2

Nonmagnetic impurity effect was studied on the n-type Fe-based superconductor BaFe1.87Co0.13As2 (Tc = 25 K) by a successful Zn substitution for Fe up to 7 at.%. Magnetic susceptibility, electrical resistivity, specific heat, and Hall coefficient measurements indicated that Tc linearly decreases with the Zn concentration and disappears at 7 at.%. The result is quantitatively comparable with what was observed for YBCO, while it disagrees with a recent report for the p-type Ba0.5K0.5Fe2As2. Fragile SC against a nonmagnetic impurity was first confirmed for the n-type 122 Fe-based superconductor.Comment: 14 pages, 5 figure