bluuebunny/crossref_metadata_2025 huggingface dataset:
Akzeptanz des fäkalen Mikrobiota-Transfers (Stuhltransplantation) als alternative Therapie bei Patienten mit Colitis ulcerosa
Authors: Roggenbrod Sebastian , Schuler Constantin , Haller Bernhard , Sohn Maximilian , Storr Martin , Schepp Wolfgang , Gundling Felix
Published: March 2019

Einleitung Die Stuhltransplantation (Fäkaler Mikrobiota-Transfer, FMT) stellt eine mögliche Behandlungsoption für die rezidivierende pseudomembranöse Colitis dar. Zusätzlich gibt es Hinweise, dass die FMT auch in der Behandlung der Colitis ulcerosa wirksam ist. Ziel dieser Studie ist die Untersuchung hinsichtlich Akzeptanz auf Patientenseite anhand eines Fragebogens.

Methodik Ein standardisierter Fragebogen aus 27 geschlossenen Fragen wurde an eine Patientenkohorte von 262 Patienten mit Colitis ulcerosa versendet. Inhalt waren Fragen u. a. zu Ablauf der FMT, Spendern sowie möglichen Bedenken. Zusätzlich wurden Aspekte des sozialen Hintergrunds sowie zur Krankheitsaktivität der Colitis ulcerosa evaluiert.

Ergebnis Die Rücklaufrate der Fragebögen lag bei 31,3 % (n = 82). 48 (58,5 %) der Patienten war die FMT bekannt. 46 (56,1 %) gaben an, bei entsprechender Indikation eine FMT durchführen zu lassen. Als Hauptmotivation wurde von 33 Patienten (40,2 %) die (vorausgesetzte) Wirksamkeit des Verfahrens sowie von 14 (17,1 %) Patienten ein Versagen aller anderen Therapien (17,1 %) genannt. Bedenken bestanden im Hinblick auf die mangelnde Testung des Transplantats hinsichtlich möglicher Infektionserreger (22, 28,9 %) sowie eine potenzielle Kontamination des Transplantats mit Gefahr einer möglichen (nachteiligen) Beeinflussung des aktuellen Krankheitsverlaufs (17, 20,7 %).

Als Verabreichungsform bevorzugten 55 Patienten (67,1 %) die FMT in Tablettenform, gefolgt von einer koloskopischen Applikation (36, 43,9 %). Als Spender wurde die vom behandelnden Arzt vorgeschlagene Person (43, 52,4 %) favorisiert. Die Bereitschaft zur FMT unterschied sich bei beiden Geschlechtern nicht signifikant (56,4 % bei ♀ vs. 57,1 % bei ♂). Bei Rauchern (88,9 %), Patienten, die auf Fernsehkonsum verzichten (77,8 %) sowie Patienten mit privater Krankenversicherung (70,6 %) war die Akzeptanz der FMT besonders hoch.

Schlussfolgerung Die FMT stellt für die Mehrheit der durch uns befragten Patienten mit Colitis ulcerosa eine erwägenswerte Therapieform mit bereits hohem Bekanntheitsgrad dar. Knapp die Hälfte der Befragten würden unter bestimmten Voraussetzungen trotz mindestens zufriedenstellenden Ansprechens auf die bisherige (konventionelle) Therapie eine FMT als alternative Behandlung erwägen. Erwartungsgemäß bestehen Bedenken im Hinblick auf die Übertragung möglicher Krankheitserreger sowie hinsichtlich der hygienekonformen Durchführung des Verfahrens.
Thiadiazoloquinoxalines
Authors: Hu Ben-Lin , Baumgarten Martin
Published: March 2019

In this account we summarized our work on the modification and extension of the thiadiazoloquinoxaline (TQ) as a strong acceptor unit for organic electronics. While also alternating conjugated copolymers with different donors were published, the focus here is the description of variation of the acceptor unit leading to many small molecules with different electronic properties as indicated from their optical absorptions, cyclic voltammetry (CV) data, density functional theory (DFT), and time-dependent (TD-DFT) calculations. The extension with ortho-diquinones seemed a promising way to enlarge the TQ molecules and further increase their electron affinity. At the end it is demonstrated how these units can be merged with other acceptors like naphthalenediimide (NDI) and be extended in an iterative way to extremely long condensed pyrene-fused heteroacenes with TQ end groups just by ring opening of the thiadiazole five-membered ring followed by further condensations in an iterative way.

1 Introduction

2 The Synthesis of TQ Cores

3 The Extension of TQ

3.1 The Extension at 4,9-Positions

3.2 The Extension at 6,7-Positions

3.3 The Extension on NDI

3.4 The Extension with TQ for Endcapping (Bis TQ)

4 Conclusions
Opening-Wedge High Tibial Osteotomy Using Autograft versus Allograft: A Systematic Review and Meta-analysis
Authors: Ren Yi-Ming , Duan Yuan-Hui , Sun Yun-Bo , Yang Tao , Hou Wei-Yu , Zhu Ru-Sen , Tian Meng-Qiang
Published: March 2019

Bone grafting is a good alternative for filling the inevitable void that is created following opening-wedge high tibial osteotomy (OWHTO). This systematic review and meta-analysis evaluated whether bone grafting is necessary for OWHTO and the successful outcomes of OWHTO using either autograft (AU) or allograft (AL). All analyzed studies were acquired from PubMed, Medline, Embase, CNKI, Google Scholar, and Cochrane Library. Data were independently extracted by two coauthors and were analyzed using RevMan5.3. Mean differences, odds ratios, and 95% confidence intervals were calculated. Cochrane Collaboration's Risk of Bias Tool and Newcastle–Ottawa Scale were used to assess the risk of bias. In total, 10 studies were assessed including three randomized controlled trials and seven observational studies. The methodological quality of the trials ranged from low to high. The overall estimate demonstrated that the difference between OWHTO using AU and AL groups and OWHTO using no filling group was not statistically significant for the loss of correction, and complications, but OWHTO using no filling group statistically showed better knee society score. Pooled results of reoperations, lateral cortex breaches, complications, and clinical function assessments showed no significant difference between AU and AL materials. Using AL statistically reduced the operative time compared with using AU. OWHTO with or without bone graft does not affect postoperative complications. No loss of correction was observed due to the lack of bone grafting. In addition, OWHTO without bone graft performs better for postoperative clinical function assessment. Complications and clinical results of medial OWHTO were similar using AL and AU and neither reported a median loss of correction of following OWHTO. Compared with using AU, using AL avoids harvest site complications and reduces operative time. To sum up, OWHTO without any bone graft is recommended for medial unicompartmental osteoarthritis of the knee. Further large-sample, multicenter, high-quality, randomized controlled trials are warranted to verify the outcomes of this meta-analysis.
The Use of Stems for Morbid Obesity in Total Knee Arthroplasty
Authors: Schultz Blake J. , DeBaun Malcolm R. , Huddleston James I.
Published: March 2019

Morbidly obese patients undergoing total knee arthroplasty have worse functional outcomes and implant survival, and increased revision rates compared with nonobese patients. In addition to increased medical comorbidities and difficult exposure, increased stress on the tibial implant and altered kinematics of knee motion contribute to aseptic loosening and medial collapse. Increased implant fixation, including use of a stemmed tibial implant, may be a way to help avoid these complications. While there is limited data on tibial stems in the morbidly obese patients specifically, cemented stemmed tibial implants should be strongly considered in these patients, especially if bone quality is poor. The initial increased cost of a stemmed implant can be justified in this high-risk patient population to minimize the risk of costly revisions related to compromised tibia component fixation.
Gender Influences Gait Asymmetry following Bicruciate-Retaining Total Knee Arthroplasty
Authors: Hennessy David , Arauz Paul , Klemt Christian , An Shuai , Kwon Young-Min
Published: March 2019

This is an experimental study. Gender has been reported to influence outcomes in patients with total knee arthroplasty (TKA) for knee osteoarthritis (OA). However, the influence of gender on three-dimensional (3D) in vivo kinematics during gait remains unclear. This study aimed to determine if 3D gait kinematics, including 3D knee translations and rotations, differed in men and women following bicruciate-retaining (BCR) TKA. Twenty-nine well-functioning unilateral BCR TKA patients (14 males and 15 females) underwent evaluation of both knees during level walking on a treadmill at a self-selected speed using a dual fluoroscopic imaging system. Interlimb comparisons of in vivo 6 degree-of-freedom kinematics were compared between male and female patients. Differences of pre- and postoperative Knee Society scores (KSSs) were compared between the groups. Both groups were matched regarding age and body mass index. Both male and female patients demonstrated improvement in their postoperative KSSs. Statistically significant differences were observed with respect to spatiotemporal anterior–posterior interlimb translations (p < 0.05). Although females presented more femoral posterior translation in the operative knee than the nonoperative knee during most of the stance phases (2.8 vs. −1.6 mm), males exhibited less femoral translation in the operative knee than the nonoperative knee (2.3 vs. −1.8 mm), when interlimb differences were detected during stance phase. Results demonstrated that there are 3D motion asymmetries of the knee in both male and female unilateral BCR TKA patients during gait with anterior–posterior interlimb asymmetries significantly greater in female than male participants. This suggests that gender may influence the in vivo knee kinematics in BCR TKA patients during gait.
Comparison of Bone Healing in Open-Wedge High Tibial Osteotomy between the Use of Allograft Bone Chips with Autologous Bone Marrow and the Use of Allograft Bone Chips Alone for Gap Filling
Authors: Kim Hee-June , Seo Il , Shin Ji-Yeon , Lee Kang San , Park Kyeong-Hyeon , Kyung Hee-Soo
Published: March 2019

The present study aimed to evaluate whether the use of allograft bone chips mixed with autologous bone marrow (BM) in the high tibial osteotomy (HTO) gap could improve the radiological and clinical results of HTO. This study analyzed 36 patients who underwent HTO with locking plate (mean age: 58.0 years). Allograft bone chips mixed with autologous BM aspirated from anterior superior iliac spine were used in 19 patients (group A) and allograft chips only were used in 17 patients (group B). The radiological and clinical results between two groups were compared during examination at 6 weeks, 3 months, 6 months, and 12 months after surgery. Clinical evaluations involving the Hospital for Special Surgery score, Knee Society knee score, and function score were performed at each assessment point. The osteotomy filling and osteoconductivity using the modified van Hemert's score were compared in each period. The clinical results were not different between the groups at all assessment points. Osteotomy filling was higher at 6 weeks and 3 months in group A than in group B (p = 0.004 and 0.005, respectively). Osteoconductivity was higher at 6 weeks and 3 months in the most medial ¼ zone in group A than in group B (p = 0.025 and 0.031, respectively). Our data shows it is beneficial to mix the allograft bone chips mixed with autologous BM after open-wedge HTO.
Reliability of 3-m Backward Walk Test in Patients with Primary Total Knee Arthroplasty
Authors: Unver Bayram , Sevik Kevser , Yarar Haci Ahmet , Unver Fatma , Karatosun Vasfi
Published: March 2019

The 3-m backward walk test (3MBWT) is used to evaluate neuromuscular control, proprioception, protective reflexes, fall risk, and balance. The aim of the present study was to determine the test–retest reliability of the 3MBWT in patients with primary total knee arthroplasty (TKA). Twenty-eight patients with primary TKA, operated by the same surgeon, were included in this study. Patients performed trials for 3MBWT twice on the same day. Between the first and second trials, patients waited for an hour on sitting position to prevent fatigue. The 3MBWT showed an excellent test–retest reliability in this study. Intraclass correlation coefficient (ICC) for 3MBWT was 0.97. The standard error of measurement and smallest real difference at the 95% confidence level for 3MBWT were 1.06 and 2.94, respectively. The 3MBWT has an excellent test–retest reliability in patients with primary TKA. It is an effective and reliable tool for measuring dynamic balance and participant falls. As a clinical test, the 3MBWT is easy to score, requires little space, has no cost, needs no special equipment, and can be applied in a short time as part of the routine medical examination.
Tuberculosis in the borderlands: migrants, microbes and more-than-human borders
Authors: Chuengsatiansup Komatra , Limsawart Wirun
Published: March 2019

Multidrug-resistant tuberculosis (MDR-TB) has been a widely recognized threat since the TB epidemic was declared a global emergency in the 1990s. The epidemic is particularly critical in the borderlands where humans and microbes move across geographic borders. In this article, we explore the contingency of human-microbe relations in Thailand-Myanmar borderlands. Initially constituted by the colonial encounters, the Siam–Burma border’s continuing existence was constantly enacted, negotiated, and co-produced through the entangled interplay of various actors, microbes and pharmaceuticals included. We examine how global forms such as biomedical science, epidemiological practices, and public health interventions were actualized in an attempt to control MDR-TB in this borderland. While disease surveillance and control were seemingly hindered by the permeability of the border and geographic mobility of migrants, the potency of Mycobacterium tuberculosis to lie dormant in human bodies for long periods of time without symptoms posed an additional challenge to epidemiological attempts to segregate the healthy from the contaminated. Combining ethnographic materials from Umphang District, Tak Province at the western border of Thailand with national policy analysis, natural history, and microbiological insights, we reveal how the indeterminacy of borders and complex microbe-human entanglements necessitate changes in the prevailing biocontainment model of infectious disease control. We propose that disease surveillance and response need to transcend the rigid geographic notion of space and include a more flexible topological conception of spatiality that embraces the fluidity of pharmaceuticals, microbes, and human relations. This reinvention of the spatial approach in epidemic control begins by attending more closely to the entanglement of human-microbe relations in the more-than-human borders.
Influence of pre-sulfurization temperature on properties of Cu2ZnSnS4 thin film in two-step sulfurization process
Authors: Liu Yaqun , Xu Jiaxiong , Yang Yuanzheng , Xie Zhiwei
Published: March 2019

In this study, Cu2ZnSnS4 (CZTS) thin films were prepared by magnetron sputtering deposition of the Cu-Zn-Sn metallic precursor (CZT) on flexible molybdenum foils and a two-step sulfurization process. Low-temperature pre-sulfurization was performed before the final high-temperature sulfurization during the two-step sulfurization process to enhance the properties of CZTS. This paper presents a method to improve the properties of CZTS thin films, making them conducive to solar cell applications. The compositions and morphologies of CZTS were confirmed using energy dispersive spectroscopy and scanning electron microscopy, respectively. X-ray diffraction was conducted to investigate the structural properties of the CZTS thin films, and the results revealed that the CZTS phase in all the samples had a preferential plane along (112). Moreover, Raman spectroscopy helped distinguish the ZnS and Cu2SnS3 phases that are close to kesterite CZTS. Compared to the thin film prepared without pre-sulfurization treatment, a suitable increase in pre-sulfurization temperature could reduce the loss of Sn and enhance the crystallinity of CZTS. However, a higher pre-sulfurization temperature could result in the formation of secondary phases. The CZTS thin films exhibited good properties when the CZT precursor was pre-sulfurized at 150 °C. In addition, the CZTS thin films had a single phase and flat and dense surfaces with large grains. The optical parameters were calculated based on the reflectance and transmittance data obtained by UV–Vis spectroscopy. The absorption coefficient was larger than 1 × 104 cm−1, and the optical bandgap was about 1.55 eV; these are suitable properties for CZTS absorption layers in CZTS thin-film solar cells.
Room-temperature spin-to-charge conversion in sputtered bismuth selenide thin films via spin pumping from yttrium iron garnet
Authors: DC Mahendra , Liu Tao , Chen Jun-Yang , Peterson Thomas , Sahu Protyush , Li Hongshi , Zhao Zhengyang , Wu Mingzhong , Wang Jian-Ping
Published: March 2019

We investigated spin-to-charge current conversion in sputtered Y3Fe5O12 (YIG)/granular bismuth selenide (GBS) bi-layers at room temperature. The spin current is pumped to the GBS layer by the precession of magnetization at ferromagnetic resonance in the YIG layer. The spin-mixing conductance is determined to be as large as (13.64 ± 1.32) × 1018 m−2, which is larger than that of YIG/Pt and comparable or better than that of YIG/crystalline bismuth selenide indicating that GBS is a good spin-sink. The figure of merit of spin-to-charge conversion, the inverse Edelstein effect length (λIEE), is estimated to be as large as (0.11 ± 0.03) nm. λIEE shows GBS film thickness dependence, and its value is three times as large as in crystalline bismuth selenide. The λIEE value larger than that of crystalline bismuth selenide and other topological insulators indicates that the spin-to-charge conversion is due to the spin-momentum locking. As the thickness of GBS increases, λIEE decreases, which means the figure-of-merit of spin-to-charge conversion is influenced by grain size.
Synthesis of greigite (Fe3S4) particles via a hydrothermal method
Authors: Moore Jonathan , Nienhuis Emily , Ahmadzadeh Mostafa , McCloy John
Published: March 2019

Greigite (Fe3S4) particles, with strong ferrimagnetic behavior, have been found to have desirable uses in the areas of biomedical and environmental applications. Size-dependent magnetic properties of greigite can play a crucial role in efficiency of its applications. This study reviews two synthetic approaches to producing such particles. The methods tested within this study include a coprecipitation synthesis and a hydrothermal process. While the coprecipitation method proved to be ineffective at producing greigite, the hydrothermal process showed promise after consistently producing greigite. For the hydrothermal process, the effects of synthesis time, autoclave atmosphere, and polyvinylpyrrolidone (PVP) addition as a capping agent to control particle growth were investigated using X-ray diffractometry (XRD) with Rietveld refinement, vibrating sample magnetometry (VSM), and scanning electron microscopy (SEM). The results show that, while pyrite (FeS2) forms as an impurity phase, increasing the synthesis time up to 18 hours increases the greigite fraction up to 70 wt% and saturation magnetization up to ∼ 35 emu/g for the powder synthesized in argon. The SEM micrographs of this sample reveal a mean greigite particle size of ∼ 700 nm. It was found that adding PVP brings about a much more uniform microstructure of agglomerated plate-shape particles with nano-sized features.
A new power MnZn ferrite for broad temperature range applications
Authors: Tsakaloudi Vasiliki , Kogias Georgios , Zaspalis Vassilios T.
Published: March 2019

The present study focuses on the targeted compositional and process design towards the development of a new MnZn ferrite material for high-efficiency power conversion systems that exhibits very low power losses at low frequencies across a broad temperature range extending from 25°C to 160°C. The MnZn ferrite powders were prepared by solid state processing, while the compositional design involved the investigation of several Co-doping levels (0 to 6000 ppm CoO) on the basic composition. Analysis of the contributions of hysteresis and eddy current power loss mechanisms to the overall power losses led to the design of further steps, targeting to the limitation of the chemical, morphological and microstructural defects, along with optimization of dopants distribution, through processing. This was achieved by the introduction of a primary heat treatment of the raw materials mixture and an optimization of the particle size distribution, both steps applied before the standard process of solid state reaction, resulting to an overall reduction of the power losses across the temperature range from 25 to 160°C. The developed MnZn ferrite material exhibits an initial permeability of 3200 at 10 kHz, 0.1 mT, 25°C, power losses <300 mW/cm3 at 100 kHz, 200 mT from 25 to 100°C and a superior magnetic performance at high temperatures, exhibiting the lowest reported power losses of 380 mW/cm3 at 100 kHz, 200 mT, 160°C, making it suitable for high energy-efficient products, independent of the environmental temperature and loading of the transformer.
Acoustic waveguide impedance matching via Helmholtz resonator mediated extraordinary acoustic transmission
Authors: Robertson William M. , Shirk Isaac , Campbell Elizabeth
Published: March 2019

We describe an acoustic impedance matching method that permits perfect sound transmission between waveguides of different impedances as set by their cross sectional areas. Impedance matching in this case is based on extraordinary acoustic transmission mediated via a Helmholtz resonator embedded at the junction between the dissimilar waveguides. Perfect transmission occurs at the Helmholtz resonance frequency. However, perfect transmission between different impedance waveguides requires that the two-neck Helmholtz resonator be asymmetric with different areas and lengths of the necks that couple to each waveguide.
Numerical modeling of the acoustically driven growth and collapse of a cavitation bubble near a wall
Authors: Boyd Bradley , Becker Sid
Published: March 2019

This paper describes the first high-order accurate, fully compressible, multiphase model to simulate the expansion and collapse of a near-wall cavitation bubble in a low-frequency ultrasound field. The model captures the compressibility of the fluids, subsequent shocks, and a physically correct representation of the acoustic input through an immersed moving boundary that represents the active face of the ultrasound transducer face. The model’s predictions of bubble dynamics are compared to existing models that are able to capture the collapse of a near wall bubble, (1) the Rayleigh growth and collapse model and (2) the Rayleigh-Plesset growth initialized collapse model, highlighting the limitations of the previously developed models.
Excitations of free and localized electrons at nearby energies in reduced cesium tungsten bronze nanocrystals
Authors: Machida Keisuke , Okada Mika , Adachi Kenji
Published: March 2019

The low-energy optical absorption mechanism of tungsten oxides and tungsten bronzes is unresolved, with the primary models reported involving free-electron and polaron excitations. Herein, a new mechanism is proposed, based on a systematic and detailed analysis of optical profiles in Cs-doped hexagonal tungsten bronze nanoparticles with varied amounts of oxygen vacancy (VO) and Cs dopant. The Drude–Lorentz analysis of absorption bands, incorporating a newly-developed Mie scattering integration method, has clarified the observed absorption profiles as consisting of three peaks of anisotropic plasmon and polaron exitations. The behavior of the deconvoluted components indicates that VO and Cs+ provide localized and delocalized electrons, respectively, both contributing to the collective plasmon resonance against external electromagnetic waves.
Direct-current current transformer for the measurement of an electric propulsion ion beam
Authors: Volkmar C. , Geile C. , Neumann A. , Hannemann K.
Published: March 2019

An important task in the development of electric propulsion devices is ground-based testing. In order to characterize electric thrusters, their generated ion beams are regarded as figures of merit and have to be well-known and understood. We present an approach to measure DC ion beam currents generated by electric thrusters by means of an inductive direct-current current transformer. In contrast to commonly used devices like Faraday cups, this device can measure the beam current non-intrusively by means of magnetic field coupling rather than charge collection. This paper shows the development of a prototype sensor which can measure currents in the typical range for electric thrusters with high resolution and satisfactory accuracy. A detailed SPICE model to assist during hardware development is also introduced and verified by test case measurements. The prototype has been tested and validated with a radio-frequency ion thruster. Its readout shows very good agreement with the output of an analytical model which computes a Gaussian-shaped ion beam in the far-field based on experimental input data.
Hydration of mixed halide perovskites investigated by Fourier transform infrared spectroscopy
Authors: Gan Zhixing , Yu Zhizhou , Meng Ming , Xia Wei , Zhang Xiaowei
Published: March 2019

The mixed lead halide perovskites are promising candidates for solar cells, but the intrinsic instabilities due to phase segregation, halide migration, and hydration hinder the practical applications. Currently, less attention is paid to the humidity induced degradation. This important issue of mixed halide perovskites is now investigated by Fourier transform infrared (FTIR) spectroscopy. After hydration of CH3NH3Pb(I1−xBrx)3, a broad band at around 3200 cm−1 of –OH vibration appears in the FTIR spectra and the bands in the range of 1200–1700 cm−1 become much stronger. The dominant FTIR mode at 1660 cm−1 due to the intermediate complex is sensitive on hydration, implying it could be used as a characteristic peak to evaluate the hydration degree of mixed halide perovskites. These information are of interest to optimize the crystal structure of this material to improve the stability so that to promote the photovoltaic applications.
Assessment of conduction mechanisms through MgO ultrathin barriers in CoFeB/MgO/CoFeB perpendicular magnetic tunnel junctions
Authors: Lv Hua , Fidalgo Joao , Silva Ana V. , Leitao Diana C. , Kampfe Thomas , Riedel Stefan , Langer Juergen , Wrona Jerzy , Ocker Berthold , Freitas Paulo P. , Cardoso Susana
Published: March 2019

Perpendicular magnetic tunnel junctions (p-MTJs) have been explored for spin transfer torque magnetic random access memory devices (STT-MRAMs). The current-induced switching (CIS) of the p-MTJs requires a relatively high current density (J); thereby, very thin insulating barriers are required, consequently increasing the risk of non-tunneling conduction mechanisms through the MgO film. In this work, we fabricated CoFeB/MgO/CoFeB p-MTJs and studied the CIS characteristics, with the obtained switching current densities of about 2 × 1010 A/m2. The filament conduction through the MgO film was induced by applying a high set current (Iset) until a significant decrease in the resistance (R) is observed. A decrease in R with increasing current (I) for parallel (P) and antiparallel (AP) states was observed. In contrast, an increase in R with the increasing I value was observed for filament p-MTJs. We used a two-channel model to extract the filament resistance (Rf) and filament current (If). The Rf dependence on the electrical power (Pf) was linearly fitted, and a heating coefficient β of about 6%/mW was obtained, which was much higher than 0.15%/mW obtained from the bulk metallic multilayers of the top electrode. The CIS for filament p-MTJs was modeled by considering the bias dependence of the tunneling and the thermal dependence of Rf, showing a significant change in the CIS curves and switching currents. Our study addresses the effect of filament conduction on the tunneling current of CoFeB/MgO/CoFeB p-MTJs, critical for the design and control of the p-MTJ based devices, such as STT-MRAMs.
Remarkable strain-rate sensitivity of nanotwinned CoCrFeNi alloys
Authors: Huo Wenyi , Fang Feng , Liu Xiaodong , Tan Shuyong , Xie Zonghan , Jiang Jianqing
Published: March 2019

Strain-rate sensitivity (SRS), which affects the mechanical properties of materials at high strain-rates and their service life, is an important indicator for nanostructured materials. In this work, via nano-indentation technology, both ultrahigh hardness (10.33 GPa) and extremely high SRS were observed in a nanotwinned (NT) nanocrystalline high-entropy alloy prepared by magnetron sputtering. The mechanism of NT materials underlying such mechanical response was explored and ascertained. It shows the evolution of the twin-boundary-affected zone volume fraction with varying nanotwin- and lattice-spacings.
Effects of surface recombination on the charge collection in h-BN neutron detectors
Authors: Maity A. , Grenadier S. J. , Li J. , Lin J. Y. , Jiang H. X.
Published: March 2019

Hexagonal boron nitride (h-BN) epilayers have been recognized as a promising material for applications in solid-state neutron detectors. However, the highest detection efficiency of 58% attained so far for 1 mm2 detectors fabricated from 50 μm thick B-10 enriched h-BN films still falls short of the expected theoretical value of 64%. This is due to the less than perfect charge collection efficiency. In this work, we have fabricated and analyzed the photocurrent-voltage characteristics of 11 h-BN neutron detectors. The dependence of the charge collection efficiency (ηc) on the charge carrier mobility-lifetime (μτ) product of the bulk trapping parameter reveals that ηc is nearly perfect at a bias voltage of 200 V if we neglect the effects of surface recombination. Our results have clearly demonstrated that the surface recombination of charge carriers is the dominant factor that prevents a further enhancement in the charge collection efficiency in our current detectors. The surface recombination field ES (=s/μ), defined as the ratio of the surface recombination velocity (s) to the carrier mobility (μ) of holes, was found to have a linear relationship with that of electrons and has a magnitude of the order of 104 V/cm. The present study indicates that it is critical to reduce ES in h-BN in order to further push the charge collection and hence the total detection efficiency of h-BN neutron detectors to 100%.
Ferroelectric and pyroelectric properties of polycrystalline La-doped HfO2 thin films
Authors: Mart C. , Kühnel K. , Kämpfe T. , Zybell S. , Weinreich W.
Published: March 2019

Lanthanum has been identified as a promising dopant to achieve ferroelectricity in HfO2 thin films in recent theoretical and experimental studies. In this work, the pyroelectric properties of 10 nm thick polycrystalline La-doped HfO2 layers manufactured by thermal atomic layer deposition are assessed employing a sinusoidal temperature profile. Compared to Si doping, La offers a broader dopant range in which ferroelectric behavior is obtained, making the material interesting for large-scale integration and deposition on area-enhanced substrates. Pyroelectric coefficients of up to −80 μC/m2 K are obtained using an optimized stoichiometry, which is comparable to earlier measurements with Si-doped HfO2 samples. Phase-sensitive evaluation of the measured current confirms the pyroelectric origin with minimal spurious contributions. The results are discussed with respect to the ferroelectric switching behavior, which is analyzed employing first-order reversal curve measurements. It is found that there is no simple linear relationship between the remanent polarization and the pyroelectric coefficient. Experimental evidence indicates that the pyroelectric response in polycrystalline thin films is modulated by internal bias fields, which can arise from charged defects. This illustrates the need for careful tuning of the manufacturing conditions and the film phase composition in future applications such as pyroelectric sensors, energy harvesting, or solid-state cooling.
Microscopic evolution of solid-hydrogen shells under the ultrafast dynamic compression
Authors: Lei Haile , Li Jun , Li Xibo , Lin Wei , Wang Kai
Published: March 2019

Starting from the same initial structure, solid-hydrogen shells were dynamically compressed at different implosion velocities by performing large-scale molecular dynamic simulations to explore their microscopic evolution under the ultrafast dynamic compression. The ultrafast dynamic compression is revealed to prohibit the solid shell from the structural phase transition, while the phase transition is first initiated at the inner surface of the shell. A faster compression generates a higher pressure in the shell at a given convergence ratio by preventing the hydrogen atoms from ejecting out of the solid-hydrogen shell to release pressure. These results provide a glimpse of the microscopic scenario of the solid-hydrogen shell at early times during the ultrafast dynamic compression, suggesting that the implosion velocity must be carefully determined to mitigate the growth of hydrodynamic instabilities on the inner surface of the solid-hydrogen shell.
Reference Correlations for the Viscosity of 13 Inorganic Molten Salts
Authors: Tasidou K. Α. , Chliatzou Ch. D. , Assael M. J. , Antoniadis K. D. , Mylona S. K. , Huber M. L. , Wakeham W. A.
Published: March 2019

In 1988, reference correlations for the viscosity of a selection of molten inorganic salts were proposed by Janz and have been used extensively. During the last 31 years, many additional measurements have been published. In a very recent paper, new reference correlations for the thermal conductivity of 13 inorganic molten salts were proposed. In this paper, reference correlations for the viscosity of those same salts are proposed. All available experimental data for the viscosity of 13 inorganic molten salts have been critically examined with the intention of establishing improved or new reference viscosity correlations. All experimental data have been categorized into primary and secondary data according to the quality of measurement specified by a series of criteria. Standard reference correlations are proposed for the following molten salts (with estimated uncertainties at the 95% confidence level given in parentheses): LiNO3 (6.7%), NaNO3 (3.0%), KNO3 (3.0%), NaBr (1.6%), KBr (2.0%), RbBr (2.2%), LiCl (3.7%), NaCl (2.4%), KCl (1.6%), RbCl (3.6%), CsCl (1.1%), NaI (1.5%), and RbI (1.5%).
p-bits: Bridging the gap between standard bits and q-bits
Authors: Patrick Chris
Published: March 2019

Researchers introduce probabilistic bits, which have the potential to advance quantum computing and machine learning using existing technology.
Synthesis and Characterisation of Indium(III) Bis-Thiosemicarbazone Complexes: 18F Incorporation for PET Imaging
Authors: Venkatachalam Taracad K. , Bernhardt Paul V. , Pierens Gregory K. , Stimson Damion H. R. , Bhalla Rajiv , Reutens David C.
Published: March 2019

Several structurally related indium chlorido complexes of bis-thiosemicarbazones were prepared, starting from the appropriately substituted bis-thiosemicarbazones, using sodium methoxide in methanol. Detailed NMR studies were conducted to assign the structure including COSY, HSQC, and HMBC techniques. The structures of all indium complexes were solved using single crystal X-ray diffraction. The chlorido ligand was present at the apex of the square pyramidal coordination sphere in all indium complexes. In some complexes, an intermolecular hydrogen bond was present between the chlorine atom and an NH group. Three different indium chlorido complexes were converted into the corresponding fluorido-derivative by a simple halide exchange method using K18F. These novel complexes, containing the positron emitting isotope 18F, may have potential applications in positron emission tomography (PET).
Altered sucrose metabolism and gene regulation in wheat (Triticum aestivum) K-type cytoplasmic male sterility
Authors: Ba Qingsong , Zhang Lanlan , Li Guiping , Zhang Gaisheng , Liu Hongzhan , Fu Zhaolin
Published: March 2019

K-Type cytoplasmic male sterility (K-CMS) plays an important role in breeding hybrid wheat. This study was designed to investigate the association of sucrose metabolism with K-CMS in wheat (Triticum aestivum L.) anthers at the binucleate stage. Levels of sucrose in the anthers of the K-CMS line remained higher than in the fertile line, but glucose and fructose contents in the anthers of the K-CMS line were dramatically lower than in the fertile line. Compared with the fertile line, the activities of cell-wall-bound invertase (CWIN), neutral invertase and vacuolar invertase (VIN) were significantly reduced. Quantitative real-time polymerase chain reaction analyses showed that the expression levels of one CWIN gene (IVR1), one VIN gene (IVR5) and a sucrose transporter gene (TaSUT1) were significantly downregulated in K-CMS anthers. Furthermore, western blot confirmed that the protein expression level of IVR1 was higher in sterile anthers than in male fertile anthers. Thus, it appears that the accumulation of sucrose in K-CMS anthers might involve a decrease in activity and a reduction in content of invertase. In conclusion, the results suggest that an inability to metabolise incoming sucrose to hexoses may be involved in the K-CMS pollen-developmental lesion.
Increasing use of general practice management and team care arrangements over time in New South Wales, Australia
Authors: Welberry Heidi , Barr Margo Linn , Comino Elizabeth J. , Harris-Roxas Ben F. , Harris Elizabeth , Harris Mark Fort
Published: March 2019

The number of older people living with chronic health conditions is increasing in Australia. The Chronic Disease Management (CDM) items program was introduced to the Medicare Benefits Schedule (MBS) to encourage a more structured approach to managing patients with chronic conditions. Initial uptake was slow and recent research has suggested that uptake is decreasing. This paper examines: person MBS CDM claims in NSW between 2006 and 2014 — using baseline survey data (2006–09) from the Sax Institute’s 45 and Up Study linked to MBS and Death Registry data (2006–14) — and MBS CDM claims per 100000 population — using billing data sourced from the Medicare Australia Statistics website — to systematically examine any changes in uptake using a time-series analysis. After age adjustment, claims for initial plans increased from 11.3% in 2006 to 22.4% in 2014. Increases were also seen for allied health service claims (from 4.1% in 2006 to 20.8% in 2014) and for plan reviews (from 5.9% in 2006 to 16.0% in 2014). These increases were consistent with the MBS summary claims data. There is evidence that these plans are appropriately targeting those in most need; however, there is limited evidence of their effect. Claims for plan reviews, although increasing, are suboptimal and may indicate poor continuity of care.
Social alliances improve rank and fitness in convention-based societies
Authors: Strauss Eli D. , Holekamp Kay E.
Published: March 2019

Significance

What forces produce and maintain social inequality, and why do society members tolerate this inequality? The “One Percent” clearly benefit from having high status, but low-status individuals have strong incentive to challenge the established pecking order and try to improve their position. This conundrum is particularly striking in the societies of many primates and spotted hyenas, where females who are born to low-status mothers rarely manage to improve their position. Here we find that females who are strongly allied with their group-mates are more likely to improve their status, and that upward social mobility is often achieved with support from their closest allies. This suggests that, much like some animals compete physically for status, these species compete through social alliances.
Optimizing schools’ start time and bus routes
Authors: Bertsimas Dimitris , Delarue Arthur , Martin Sebastien
Published: March 2019

Significance

Spreading start times allows school districts to reduce transportation costs by reusing buses between schools. However, assigning each school a time involves both estimating the impact on transportation costs and reconciling additional competing objectives. These challenges force many school districts to make myopic decisions, leading to an expensive and inequitable status quo. For instance, most American teenagers start school before 8:00 AM, despite evidence of significant associated health issues. We propose an algorithm to jointly solve the school bus routing and bell time selection problems. Our application in Boston led to $5 million in yearly savings (maintaining service quality despite a 50-bus fleet reduction) and to the unanimous approval of the first school start time reform in 30 years.
Students of color show health advantages when they attend schools that emphasize the value of diversity
Authors: Levine Cynthia S. , Markus Hazel Rose , Austin Makeda K. , Chen Edith , Miller Gregory E.
Published: March 2019

Significance

The United States is increasingly diverse, especially among youth. At the same time, racial and ethnic gaps persist in many domains, including risk for cardiovascular disease. Here, we use a diverse sample of adolescents in a mostly urban setting to show that when schools emphasize the value of diversity, students of color are healthier. Thus, schools’ climates around diversity may have a role to play in reducing health disparities.
Incentivizing hospital infection control
Authors: Drohan Sarah E. , Levin Simon A. , Grenfell Bryan T. , Laxminarayan Ramanan
Published: March 2019

Significance

As populations age and hospitalization becomes more common, healthcare-associated infections, including many caused by drug-resistant pathogens, are increasing in importance. Because healthcare facilities share patients, healthcare-associated pathogens spread easily between facilities. Each institution, therefore, has an incentive to free ride on the infection control efforts of other institutions. A feasible policy is to compensate hospitals for infection control. Here we explore the effect of different forms of subsidies on hospitals’ infection control. Under a limited budget, we find that the most effective subsidy is a dollar-for-dollar matching subsidy. Additionally, we show that a subsidy should be preferentially given to hospitals with lower transmission rates. Economic incentives strongly influence hospital behavior and understanding these is a useful complement to epidemiological analysis alone.
Taurine transporter (TauT) deficiency impairs ammonia detoxification in mouse liver
Authors: Qvartskhava Natalia , Jin Cheng Jun , Buschmann Tobias , Albrecht Ute , Bode Johannes Georg , Monhasery Niloufar , Oenarto Jessica , Bidmon Hans Jürgen , Görg Boris , Häussinger Dieter
Published: March 2019

Significance

Taurine transporter deficiency in mice results in hyperammonemia and reduced glutamine formation in hepatic scavenger cells due to an impaired ammonia transport at 3 months of age and a tyrosine nitration-dependent inactivation of glutamine synthetase in 12-month-old mice. The data suggest that down-regulation of the ammonia transporter RhBG can be rate limiting for the synthesis of glutamine in mouse liver.
Wildfires and climate change push low-elevation forests across a critical climate threshold for tree regeneration
Authors: Davis Kimberley T. , Dobrowski Solomon Z. , Higuera Philip E. , Holden Zachary A. , Veblen Thomas T. , Rother Monica T. , Parks Sean A. , Sala Anna , Maneta Marco P.
Published: March 2019

Climate change is increasing fire activity in the western United States, which has the potential to accelerate climate-induced shifts in vegetation communities. Wildfire can catalyze vegetation change by killing adult trees that could otherwise persist in climate conditions no longer suitable for seedling establishment and survival. Recently documented declines in postfire conifer recruitment in the western United States may be an example of this phenomenon. However, the role of annual climate variation and its interaction with long-term climate trends in driving these changes is poorly resolved. Here we examine the relationship between annual climate and postfire tree regeneration of two dominant, low-elevation conifers (ponderosa pine and Douglas-fir) using annually resolved establishment dates from 2,935 destructively sampled trees from 33 wildfires across four regions in the western United States. We show that regeneration had a nonlinear response to annual climate conditions, with distinct thresholds for recruitment based on vapor pressure deficit, soil moisture, and maximum surface temperature. At dry sites across our study region, seasonal to annual climate conditions over the past 20 years have crossed these thresholds, such that conditions have become increasingly unsuitable for regeneration. High fire severity and low seed availability further reduced the probability of postfire regeneration. Together, our results demonstrate that climate change combined with high severity fire is leading to increasingly fewer opportunities for seedlings to establish after wildfires and may lead to ecosystem transitions in low-elevation ponderosa pine and Douglas-fir forests across the western United States.
Regulation of arousal via online neurofeedback improves human performance in a demanding sensory-motor task
Authors: Faller Josef , Cummings Jennifer , Saproo Sameer , Sajda Paul
Published: March 2019

Our state of arousal can significantly affect our ability to make optimal decisions, judgments, and actions in real-world dynamic environments. The Yerkes–Dodson law, which posits an inverse-U relationship between arousal and task performance, suggests that there is a state of arousal that is optimal for behavioral performance in a given task. Here we show that we can use online neurofeedback to shift an individual’s arousal from the right side of the Yerkes–Dodson curve to the left toward a state of improved performance. Specifically, we use a brain–computer interface (BCI) that uses information in the EEG to generate a neurofeedback signal that dynamically adjusts an individual’s arousal state when they are engaged in a boundary-avoidance task (BAT). The BAT is a demanding sensory-motor task paradigm that we implement as an aerial navigation task in virtual reality and which creates cognitive conditions that escalate arousal and quickly results in task failure (e.g., missing or crashing into the boundary). We demonstrate that task performance, measured as time and distance over which the subject can navigate before failure, is significantly increased when veridical neurofeedback is provided. Simultaneous measurements of pupil dilation and heart-rate variability show that the neurofeedback indeed reduces arousal. Our work demonstrates a BCI system that uses online neurofeedback to shift arousal state and increase task performance in accordance with the Yerkes–Dodson law.
Transcriptional factor ATF3 protects against colitis by regulating follicular helper T cells in Peyer’s patches
Authors: Cao Yingjiao , Yang Qiong , Deng Hui , Tang Jinyi , Hu Jiancong , Liu Huanliang , Zhi Min , Ye Linsen , Zou Bin , Liu Yongdong , Wei Lai , Gabrilovich Dmitry I. , Wang Haikun , Zhou Jie
Published: March 2019

Significance

The mechanisms underlying gut follicular helper T (T
FH
) cells and their role in mucosal homeostasis is not fully understood. In this study, we demonstrate that activating transcription factor 3 (ATF3) represents a regulator of gut TFH cells, which dictates the susceptibility of colitis. Bcl6 was identified as a transcriptional target of ATF3 in gut T
FH
cells.