14 research outputs found

    Controlling the superconducting transition by spin-orbit coupling

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    Whereas there exists considerable evidence for the conversion of singlet Cooper pairs into triplet Cooper pairs in the presence of inhomogeneous magnetic fields, recent theoretical proposals have suggested an alternative way to exert control over triplet generation: intrinsic spin-orbit coupling in a homogeneous ferromagnet coupled to a superconductor. Here, we proximity-couple Nb to an asymmetric Pt/Co/Pt trilayer, which acts as an effective spin-orbit coupled ferromagnet owing to structural inversion asymmetry. Unconventional modulation of the superconducting critical temperature as a function of in-plane and out-of-plane applied magnetic fields suggests the presence of triplets that can be controlled by the magnetic orientation of a single homogeneous ferromagnet. Our studies demonstrate for the first time an active role of spin-orbit coupling in controlling the triplets – an important step towards the realization of novel superconducting spintronic devices

    Additional file 1: of On the Current Drive Capability of Low Dimensional Semiconductors: 1D versus 2D

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    On the Current Drive Capability of Low Dimensional Semiconductors -1D versus 2D –. The current calculation for parabolic E-k relation and the disscusion of temperture dependence is shown in the addtional file. Figure S1. shows the difference of 1D and 2D currrent under T=0k & T=300K

    Experimental confirmation of Zener-polaron-type charge and orbital ordering in Pr1−xCaxMnO3

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    Pr1-xCaxMnO3 in the doping range between 0.3 < x < 0.5 represent an extremely interesting manganite system for the study of the interplay of different kinds of ordering (charge, orbital, lattice, and spin). While there is consensus that a charge- and orbital-ordered state develops below a transition temperature T-co approximate to 230 K, recent controversial structural refinements resulting from neutron and x-ray diffraction studies challenged our understanding of the particular type of charge ordering (CO) and orbital ordering (OO), and consequently, the underlying mechanism of the colossal resistance effects. Here, we present a detailed high-resolution transmission electron microscopy and electron-diffraction study that, based on extinction rules, resolves the current controversy and confirms the existence of the Zener-polaron (ZP)-type CO and/or OO in Pr1-xCaxMnO3. The ZP-type ordering is further verified by atomic-column-resolved electron energy-loss spectroscopy revealing strong charge ordering of the in-plane oxygen-Mn bonds, while valence disproportionation at the Mn sites is less than expected. Over wide doping and temperature ranges, we observed structural phase coexistence between the ZP-CO/OO P2(1)nm and the disordered Pbnm structure

    Multiple Phase Inversion of Emulsions Stabilized by <i>in Situ</i> Surface Activation of CaCO<sub>3</sub> Nanoparticles via Adsorption of Fatty Acids

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    The <i>in situ</i> surface activation of raw CaCO<sub>3</sub> nanoparticles by interaction with a series of sodium carboxylates of chain length between 6 and 12 as well as sodium 2-ethylhexylsulfosuccinate (AOT) was studied, and the impact of this on the stabilization and phase inversion of toluene–water emulsions was assessed. By using complementary experiments including measurement of particle zeta potentials, adsorption isotherms of amphiphile, and relevant contact angles, the mechanism of this activation was revealed. The results show that hydrophilic CaCO<sub>3</sub> nanoparticles can be surface activated by interaction with sodium carboxylates and AOT even if they are not surface-active themselves. Both the electrostatic interaction between the positive charges on particle surfaces and the negative charges of anionic amphiphile headgroups and the chain–chain interactions of the amphiphile result in monolayer adsorption of the amphiphile at the particle–water interface. This transforms the particles from hydrophilic to partially hydrophobic such that they become surface-active and stabilize oil-in-water O/W(1) emulsions and induce O/W(1) → water-in-oil W/O phase inversion, depending on the chain length of the carboxylate molecules. At high amphiphile concentration, bilayer or hemimicelle adsorption may occur at the particle–water surface, rendering particles hydrophilic again and causing their desorption from the oil–water interface. A second phase inversion, W/O → O/W(2), may occur depending on the surface activity of the amphiphile. CaCO<sub>3</sub> nanoparticles can therefore be made good stabilizers of both O/W and W/O emulsions once surface activated by mixing with traces of suitable anionic amphiphile

    Association of off-the-job training with work performance and work-family conflict among physicians: A cross-sectional study in China

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    Objectives To determine whether experiences of off-the-job training in domestic (DT) and overseas study (OS) settings are associated with work performance and work-family conflict in physicians. Design, setting and participants We conducted a national cross-sectional survey in 77 public hospitals across seven provinces in China between July 2014 and April 2015. Participants were 3182 physicians. Exposure Participants were categorised into four groups: none, DT only, OS only and DT and OS. Primary outcome measures Work performance was assessed by work engagement, career attrition and patient-centred care. Work-family conflict was assessed by affecting care for family, feeling guilty towards family and receiving complaints from family. Results A total of 25.89% participants had experienced DT only, 8.71% OS only and 8.47% DT and OS. After adjustment for potential confounders, participants who had experiences of DT and OS compared with those with no training were more likely to report positive work performance (pride in work: OR=2.11, 95% CI: 1.43 to 3.10; enjoyment of work: OR=1.67, 95% CI: 1.11 to 2.51; turnover intention: OR=0.54, 95% CI: 0.38 to 0.77; early retirement: OR=0.63, 95% CI: 0.45 to 0.89; and exhaustion: OR=0.66, 95% CI: 0.45 to 0.98) and less work-family conflicts (feeling guilty towards family: OR=0.51, 95% CI: 0.35 to 0.74; and complaints from family: OR=0.66, 95% CI: 0.47 to 0.91). We found no obvious association between DT/OS experience with patient-centred care. Conclusions Physicians with DT and OS experiences are more likely to have better work performance and less work-family conflict than those without such experience. Physicians face increasing pressure to pursue continuing education and experience associated distress. Therefore, hospitals and government policy-makers should promote DT and OS

    Aminated Poly(glycidyl methacrylate)s for Constructing Efficient Gene Carriers

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    Aminated poly­(glycidyl methacrylate) (PGMA) vectors could efficiently mediate gene delivery. Recently, we reported that ethanolamine (EA)-functionalized PGMA could provide high transfection efficiency, while exhibiting very low toxicity. Herein, different amine species, including 1-amino-2-propanol (AP1), 3-amino-2-propanol (AP2), EA, and <i>N,N,</i>-dimethylethylenediamine (DED), and its quaternized DED, were proposed to aminate PGMA. The DNA condensation abilities, pH buffering capacities, cytotoxicities, and gene transfection efficiencies of the resultant aminated PGMA vectors were systematically compared. Compared with EA, AP1 (or AP2) contains an additional methyl (or methylene) group. EA-, AP1-, and AP2-functionalized PGMA vectors exhibited similar condensation abilities. The methyl (from AP1) and methylene (from AP2) species could benefit the gene delivery. The transfection performance mediated by AP1-functionalized PGMA is best. DED possesses a tertiary amine group, which could be quaternized to further enhance the DNA condensation ability of aminated PGMA. No obvious increase in cytotoxicity of quaternized DED-aminated PGMA was observed. But both DED- and its quaternized counterpart-functionalized PGMA vectors exhibited very low pH buffering capacities, making them exhibit poor gene transfection performances. The current study would provide useful information for constructing better PGMA-based delivery systems with good biophysical properties

    The global prevalence of premature ovarian insufficiency: a systematic review and meta-analysis

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    The objective of this review was to answer the global prevalence of premature ovarian insufficiency (POI), and explore the associated factors including etiopathology and regions with POI. The search was conducted on reports from a total of eight databases that comprised Chinese National Knowledge Infrastructure (CNKI), Wanfang, China BioMedical Literature Database (CBM), PubMed, the Cochrane Library, Embase, Web of Science and Ovid MEDLINE® between 1946 and 2021. To analyze the source of heterogeneity, we performed subgroup analysis based on different etiologies and regions. Meta-analysis was carried out by Stata14.0 software. The results showed that the global overall prevalence of POI among women was 3.5%. By subgroup analysis, the prevalence of POI among women with iatrogenic etiology was 11.2%, followed by autoimmunity (10.5%); the prevalence of POI by region was 11.3% at the highest in North America followed by South America (5.4%); and the prevalence of POI was 5.3% in a developing country, higher than 3.1% in a developed country. The trend of prevalence of POI over the past 20 years was on the rise (although p > 0.05). We recommend that health and medical institutions strengthen public health awareness, achieve health-education goals related to POI and increase women’s awareness of and attention to POI.</p

    Characterization of genome-wide H3K27ac profiles reveals a distinct PM2.5-associated histone modification signature.

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    BACKGROUND: Current studies of environmental health suggest a link between air pollution components, such as particulate matter (PM), and various diseases. However, the specific genes and regulatory mechanisms implicated in PM-induced diseases remain largely unknown. Epigenetic systems such as covalent modification of histones in chromatin may mediate environmental factors in gene regulation. Investigating the relationships between PM exposure and histone modification status may help understand the mechanisms underlying environment-associated health conditions. METHODS: In this study, we obtained genome-wide profiles of H3K27ac (histone 3 lysine 27 acetylation), known to be an active gene regulatory histone modification marker, in blood samples collected from four Chinese individuals exposed to high or low PM2.5 (particles with diameters up to 2.5 μm). RESULTS: The genome-wide chromatin immunoprecipitation sequencing (ChIP-Seq) data indicated a comprehensive differential H3K27ac landscape across the individual genomes, which was associated with high PM2.5. Moreover, a substantial number of these PM2.5-associated differential H3K27ac markers were in genes involved in immune cell activation, potentially linking these epigenetic changes with air pollution-induced immune and inflammatory responses. CONCLUSIONS: Our study provides the first genome-wide characterization of H3K27ac profiles in individuals subjected to different exposure levels of PM2.5. Future systematic investigations of the relationships between air pollutants and histone modifications in large population samples are warranted to elucidate the contributions of histone modifications to environment-associated diseases
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