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GaAsBi nanowires represent a novel and promising material platform for future nano-photonics. However, the growth of high-quality GaAsBi nanowires and GaAsBi alloy is still a challenge due to a large miscibility gap between GaAs and GaBi. In this work we investigate effects of Bi incorporation on lattice dynamics and carrier recombination processes in GaAs/GaAsBi core/shell nanowires grown by molecular-beam epitaxy. By employing photoluminescence (PL), PL excitation, and Raman scattering spectroscopies complemented by scanning electron microscopy, we show that increasing Bi-beam equivalent pressure (BEP) during the growth does not necessarily result in a higher alloy composition but largely affects the carrier localization in GaAsBi. Specifically, it is found that under high BEP, bismuth tends either to be expelled from a nanowire shell towards its surface or to form larger clusters within the GaAsBi shell. Due to these two processes the bandgap of the Bi-containing shell remains practically independent of the Bi BEP, while the emission spectra of the NWs experience a significant red shift under increased Bi supply as a result of the localization effect. [ABSTRACT FROM AUTHOR]

This study attempted to investigate whether exosomes derived from rat endothelial cells (EC-Exo) attenuate intimal hyperplasia after balloon injury using hematoxylin and eosin staining, immunohistochemistry, immunofluorescence staining, Evans blue staining, and Western blotting. The results indicated that EC-Exo inhibited intimal hyperplasia in the carotid artery after balloon injury, promoted re-endothelialization, and reduced vascular inflammation and ROS-NLRP3-mediated cell pyroptosis. Thus, EC-Exo can inhibit neointimal hyperplasia after carotid artery injury in rats presumably by inhibiting the ROS-NLRP3 inflammasome and phenotypic transformation of vascular smooth muscle cells. [ABSTRACT FROM AUTHOR]

Objectives: This propensity score–matched population-based cohort study compared stroke risk between patients with type 2 diabetes mellitus with and without preexisting sarcopenia. Research Design and Methods: We used data from Taiwan's National Health Insurance Research Database for the period from January 2008 to December 2019. We recruited patients with type 2 diabetes mellitus and categorized them into two groups at a ratio of 1:1 on the basis of diagnosed sarcopenia. The matching variables were age, sex, income level, urbanization level, diabetes severity (adapted Diabetes Complications Severity Index [aDCSI Scores]), Charlson Comorbidity Index (CCI), other comorbidities associated with stroke, smoking status, medication use, and types of antidiabetic medications. The matching process yielded a final cohort of 104,120 patients (52,060 and 52,060 in the sarcopenia and nonsarcopenia groups, respectively) who were eligible for inclusion in subsequent analyses. Results: In the multivariate Cox regression analysis, the adjusted hazard ratio (aHR; 95% CI) of stroke for the sarcopenia diabetes group compared with the control group was 1.13 (1.{vn10}, 1.16; P < 0.001), after controlling for age, sex, CCI, and aDCSI scores. The incidence rates of stroke for the sarcopenia and nonsarcopenia groups were 295.98 and 260.68 per 10,000 person-years, respectively. The significant IRR (95% CI) of stroke was 1.14 (1.09, 1.17) for the sarcopenia diabetes group compared with the nonsarcopenic diabetes group. Conclusion: Preexisting sarcopenia increased the risk of stroke in patients with type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

We theoretically study helicity-dependent photocurrent in a three-dimensional topological insulator Bi2Te3 under elastic scattering of different symmetries. By exploring spin-selective optical transitions and symmetry-breaking scattering, we are able to address the out-of-plane spin texture of the topological helical surface states and to generate directional, spin-polarization tunable photocurrent that is otherwise forbidden for the original C3v symmetry of the surface. This can be achieved regardless of the Fermi level, even under the condition when the topological states are inaccessible in dark. This work paves the way to robustly explore the out-of-plane spin texture for harvesting opto-spintronic functionalities of topological insulators. [ABSTRACT FROM AUTHOR]

Electrical and electroluminescent properties were studied for GaN/InGaN light-emitting diodes (LEDs) with the n-GaN layer up and with the top portion of the n layer made of undoped GaMnN to allow polarization modulation by applying an external magnetic field (so-called "spin-LEDs"). The contact annealing temperature was kept to 750°C, which is the thermal stability limit for retaining room-temperature magnetic ordering in the GaMnN layer. Measurable electroluminescence (EL) was obtained in these structures at threshold voltages of ∼15 V, with a lower EL signal compared to control LEDs without Mn. This is related to the existence of two parasitic junctions between the metal and the lower contact p-type layer and between the GaMnN and the n-GaN in the top contact layer. [ABSTRACT FROM AUTHOR]

The long noncoding RNA TINCR shows aberrant expression in human squamous carcinomas. However, its expression and function in gastric cancer remain unclear. We report that TINCR is strongly upregulated in human gastric carcinoma (GC), where it was found to contribute to oncogenesis and cancer progression. We also revealed that TINCR overexpression is induced by nuclear transcription factor SP1. Silencing TINCR expression inhibited cell proliferation, colony formation, tumorigenicity and apoptosis promotion, whereas TINCR overexpression promoted cell growth, as documented in the SGC7901 and BGC823 cell lines. Mechanistic analyses indicated that TINCR could bind to STAU1 (staufen1) protein, and influence KLF2 mRNA stability and expression, then KLF2 regulated cyclin-dependent kinase genes CDKN1A/P21 and CDKN2B/P15 transcription and expression, thereby affecting the proliferation and apoptosis of GC cells. Together, our findings suggest that TINCR contributes to the oncogenic potential of GC and may constitute a potential therapeutic target in this disease. [ABSTRACT FROM AUTHOR]

Lattice constants, total energies, and densities of state of alkali-earth metals Be, Mg, Ca, Sr, Ba and Ra in group IIA with competing crystalline structures were calculated via the Perdew-Burke-Ernzerhof parameterization of generalized gradient approximation with ultra-soft pseudo-potential method (PBE-GGA-USPP) in the density functional theory. The lattice stabilities of Be, Mg, Ca and Sr agree well with those of the Perdew-Wang parameterization of generalized gradient approximation with projector augmented-wave method (PW91-GGA-PAW) in density functional theory and the CALPHAD method. The lattice stability of Ba agrees with that of PW91-GGA-PAW method in first-principles but disagrees with the result of CALPHAD method for the stability of competing hcp and fcc structures. The lattice stability of Ra is calculated and agrees with the experimental fact. Analyses of the electronic structures show that the p state of electrons contributes mainly to the density of state (DOS) for Be and Mg and the d state plays main role in that of Ca, Sr, Ba and Ra. [ABSTRACT FROM AUTHOR]

Personality traits are summarized by five broad dimensions with pervasive influences on major life outcomes, strong links to psychiatric disorders and clear heritable components. To identify genetic variants associated with each of the five dimensions of personality we performed a genome-wide association (GWA) scan of 3972 individuals from a genetically isolated population within Sardinia, Italy. On the basis of the analyses of 362 129 single-nucleotide polymorphisms we found several strong signals within or near genes previously implicated in psychiatric disorders. They include the association of neuroticism with SNAP25 (rs362584, P=5 × 10−5), extraversion with BDNF and two cadherin genes (CDH13 and CDH23; Ps<5 × 10−5), openness with CNTNAP2 (rs10251794, P=3 × 10−5), agreeableness with CLOCK (rs6832769, P=9 × 10−6) and conscientiousness with DYRK1A (rs2835731, P=3 × 10−5). Effect sizes were small (less than 1% of variance), and most failed to replicate in the follow-up independent samples (N up to 3903), though the association between agreeableness and CLOCK was supported in two of three replication samples (overall P=2 × 10−5). We infer that a large number of loci may influence personality traits and disorders, requiring larger sample sizes for the GWA approach to confidently identify associated genetic variants. [ABSTRACT FROM AUTHOR]

Monoclonal gammopathy of undetermined significance (MGUS) was identified in 3.2% of 21 463 residents of Olmsted County, Minnesota, 50 years of age or older. The risk of progression to multiple myeloma, Waldenstrom's macroglobulinemia, AL amyloidosis or a lymphoproliferative disorder is approximately 1% per year. Low-risk MGUS is characterized by having an M protein <15 g/l, IgG type and a normal free light chain (FLC) ratio. Patients should be followed with serum protein electrophoresis at six months and, if stable, can be followed every 2-3 years or when symptoms suggestive of a plasma cell malignancy arise. Patients with intermediate and high-risk MGUS should be followed in 6 months and then annually for life. The risk of smoldering (asymptomatic) multiple myeloma (SMM) progressing to multiple myeloma or a related disorder is 10% per year for the first 5 years, 3% per year for the next 5 years and 1-2% per year for the next 10 years. Testing should be done 2-3 months after the initial recognition of SMM. If the results are stable, the patient should be followed every 4-6 months for 1 year and, if stable, every 6-12 months. [ABSTRACT FROM AUTHOR]

The flux pinning potential energy of silver (Ag) sheathed high- T c Bi-2223 tapes determined from measured current densities, J( T, H), is reported in this paper. Measurements of the transport current density, J, of the Ag sheathed Bi-2223 tapes were performed with an applied magnetic field directions parallel ( H| ab) and perpendicular ( H| c) to the tape’s board surface from 0 to 3 T, at temperatures from 23 to 77 K. To obtain the pinning potential energy of the Bi-2223 superconductor, an empirical scaling of J( T, H) is introduced in this study. Under the flux dynamics, the effective pinning energy, Ueff( T, H, J), can be formulated using the measured current density, J( T, H). Furthermore, the pinning potential energies, U( T, H), for both H| ab and H| c were quantitatively determined by the scaling of J( T, H). The two energies, U( T, H), exhibit as a function that is inversely proportional to both temperature and logarithmic magnetic field. The magnitude of U( T, H) for H|ab is three or more times larger than that for H| c under the considered conditions. The U( T, H) is sensitive to the temperature, but insensitive to the magnetic field. This characteristic of insensitiveness towards magnetic field is an advantage for applications on the conditions of high current density, high magnetic field, and low temperature. [ABSTRACT FROM AUTHOR]

The flux pinning potential energy of silver (Ag) sheathed high- T c Bi-2223 tapes determined from measured current densities, J( T, H), is reported in this paper. Measurements of the transport current density, J, of the Ag sheathed Bi-2223 tapes were performed with an applied magnetic field directions parallel ( H| ab) and perpendicular ( H| c) to the tape’s board surface from 0 to 3 T, at temperatures from 23 to 77 K. To obtain the pinning potential energy of the Bi-2223 superconductor, an empirical scaling of J( T, H) is introduced in this study. Under the flux dynamics, the effective pinning energy, Ueff( T, H, J), can be formulated using the measured current density, J( T, H). Furthermore, the pinning potential energies, U( T, H), for both H| ab and H| c were quantitatively determined by the scaling of J( T, H). The two energies, U( T, H), exhibit as a function that is inversely proportional to both temperature and logarithmic magnetic field. The magnitude of U( T, H) for H|ab is three or more times larger than that for H| c under the considered conditions. The U( T, H) is sensitive to the temperature, but insensitive to the magnetic field. This characteristic of insensitiveness towards magnetic field is an advantage for applications on the conditions of high current density, high magnetic field, and low temperature. [ABSTRACT FROM AUTHOR]

In this work, we address the issue of spin relaxation and its relevance to spin detection in ZnO-based materials, by spin-polarized, time-resolved magneto-optical spectroscopy. We have found that spin relaxation is very fast, i.e. about 100 ps for donor bound excitons in wurtzite ZnO, despite of a weak spin–orbit interaction. We also reveal that alloying of ZnO with Cd enhances spin relaxation, prohibiting ZnCdO/ZnO structures for efficient optical spin detection. On the other hand, a variation in strain field induced by lattice mismatch with substrates does not seem to lead to a noticeable change in spin relaxation. The observed fast spin relaxation, together with the limitation imposed by the band structure, are thus identified as the two most important factors that limit the efficiency of optical spin detection in the studied ZnO-based materials. [ABSTRACT FROM AUTHOR]

Generating, manipulating and detecting electron spin polarization and coherence at room temperature is at the heart of future spintronics and spin-based quantum information technology. Spin filtering, which is a key issue for spintronic applications, has been demonstrated by using ferromagnetic metals, diluted magnetic semiconductors, quantum point contacts, quantum dots, carbon nanotubes, multiferroics and so on. This filtering effect was so far restricted to a limited efficiency and primarily at low temperatures or under a magnetic field. Here, we provide direct and unambiguous experimental proof that an electron-spin-polarized defect, such as a Gai self-interstitial in dilute nitride GaNAs, can effectively deplete conduction electrons with an opposite spin orientation and can thus turn the non-magnetic semiconductor into an efficient spin filter operating at room temperature and zero magnetic field. This work shows the potential of such defect-engineered, switchable spin filters as an attractive alternative to generate, amplify and detect electron spin polarization at room temperature without a magnetic material or external magnetic fields. [ABSTRACT FROM AUTHOR]

ZnO is an attractive candidate for spintronics studies because of its potential for exhibiting high Curie temperatures and the relative lack of ferromagnetic second phases in the material. In this paper, we review experimental results on transition-metal (TM) doping of ZnO and the current state of theories for ferromagnetism. It is important to re-examine some of the earlier concepts for spintronics devices, such as the spin field-effect transistor, to account for the presence of the strong magnetic field that has deleterious effects. In some of these cases, the spin device appears to have no advantage relative to the conventional charge-control electronic analog. We have been unable to detect optical spin polarization in ZnO. [ABSTRACT FROM AUTHOR]

PurposeTo determine the association between hospital and surgeon volume with the incidence of postoperative endophthalmitis.MethodsA prospective cohort study was conducted to analyse the national health insurance claims data of those patients receiving cataract surgery in 2000 in Taiwan. A total of 108 705 patients who received cataract surgery by 1004 surgeons at 494 hospitals were followed to the end of 2002. Stepwise Cox regression was used to analyse the effects of hospital and surgeon volume of cataract surgery on postoperative endophthalmitis after adjustment for patient's age, gender, education, ophthalmic comorbidities, general comorbidities, and surgical factors including operative methods, different types of intraocular lenses, and surgeon's age.ResultsThe 2-year incidence of postoperative endophthalmitis at high-volume hospitals (0.90%) was lower than low-volume hospitals (1.16%). The incidence of postoperative endophthalmitis by high-volume surgeons (0.59%) was lower than those by middle-high-volume (0.73%), middle-low-volume (0.80%), or low-volume surgeons (1.16%). After controlling for case mix, the risk of postoperative endophthalmitis of the low-volume hospitals (hazard ratio (HR)=1.39) was higher than that of the high-volume hospitals. The risk of postoperative endophthalmitis of low-volume surgeons (HR=1.67) was higher than that of the high-volume surgeons.ConclusionsThe provider volume (hospital and surgeon volume) is associated with the risk of postoperative endophthalmitis. The patients who receive cataract surgery at low-volume hospitals or by low-volume surgeons have significantly higher risk of postoperative endophthalmitis than at high-volume hospitals or by high-volume surgeons. Provider volume can be considered in further postoperative endophthalmitis study as a risk factor.Eye (2006) 20, 900–907. doi:10.1038/sj.eye.6702045; published online 19 August 2005 [ABSTRACT FROM AUTHOR]

The interfacial reaction between electroless Ni(P) under-bump metallization (UBM) and solders is studied. A P-rich layer forms in the UBM along the solder side after reflow and thermal aging. Crack formation inside the P-rich layer can sometimes penetrate throughout the entire UBM layer structure. The Ni(P) UBM degradation occurs earlier in the Sn3.5Ag solder than in Sn37Pb because of its higher reflow temperature. Despite the formation of a P-rich layer and cracks inside the UBM, it still keeps its original function within the high-temperature storage period in this study. Explanations for the formation of the P-rich layer and cracks in the UBM are outlined along with explanations for the Ni(P) UBM degradation process. [ABSTRACT FROM AUTHOR]

Summary In this paper, we analyze global, direct and diffuse solar radiation data on a horizontal surface observed at stations in Shanghai, Nanjing and Hangzhou for the period of 1961 to 2000. The data include monthly averages of the daily clearness index (G/G0: the ratio of global to extraterrestrial solar radiation) and the diffuse fraction (D/G: the ratio of diffuse to global solar radiation. The present study has processed and analyzed the data, including variables or statistics of mean, and annual monthly and daily total, the diurnal variation and the frequency of daily totals of global solar radiation. A correlation between daily values of clearness index and diffuse fraction is obtained and recommended correlation equations were calculated. The annual variations and trend of yearly series are analyzed for daily global, direct and diffuse radiation on a horizontal surface, as well as for daily clearness index and diffuse fraction in Shanghai, Nanjing and Hangzhou. The results show: 1) the east China is characterized by a decrease in global and direct radiation and a little increase in diffuse radiation and a negative linear relationship was obtained between clearness index and diffuse fraction. 2) The annual variations of global, direct and diffuse radiation for Shanghai, Nanjing and Hangzhou are similar with relative low values of global and direct radiation in June due to the Meiyu period. 3) The acceleration of air pollution and decrease of relative sunshine are the possible causes for the decrease of global and direct radiation. [ABSTRACT FROM AUTHOR]

(Ga,Mn)N/InGaN multiquantum well (MQW) diodes were grown by molecular beam epitaxy (MBE). The current-voltage characteristics of the diodes show the presence of a parasitic junction between the (Ga,Mn)N and the n-GaN in the top contact layer due to the low conductivity of the former layer. Both the (Ga,Mn)N/InGaN diodes and control samples without Mn doping show no or very low (up to 10% at the lowest temperatures) optical (spin) polarization at zero field or 5 T, respectively. The observed polarization is shown to correspond to the intrinsic optical polarization of the InGaN MQW, due to population distribution between spin sublevels at low temperature, as separately studied by resonant optical excitation with a photon energy lower than the bandgap of both the GaN and (Ga,Mn)N. This indicates efficient losses in the studied structures of any spin polarization generated by optical spin orientation or electrical spin injection. The observed vanishing spin injection efficiency of the spin light-emitting diode (LED) is tentatively attributed to spin losses during the energy relaxation process to the ground state of the excitons giving rise to the light emission. [ABSTRACT FROM AUTHOR]

A ZnSSe/ZnMnSe type-II semimagnetic superlattice was pseudomorphically grown via molecular beam epitaxy on a GaAs substrate. The superlattice-layer thicknesses and compositions were chosen so that compressive strains in the ZnMnSe layer compensated tensile strains in the ZnSSe layer. The photoluminescence spectra in an external magnetic field demonstrate the effect of "giant Zeeman splitting of an exciton". Simulation of the luminescence-line shift in a magnetic field allowed us to determine more accurately the band offsets at the ZnSSe/ZnMnSe interface. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) topological insulator (TI) is a unique quantum phase of matter with exotic physical properties and promising spintronic applications. However, surface spin current in a common 3D TI remains difficult to control and the out-of-plane spin texture is largely unexplored. Here, by means of surface spin photocurrent in Bi2Te3 TI devices driven by circular polarized light, we identify the subtle effect of the spin texture of the topological surface state including the hexagonal warping term on the surface current. By exploring the out-of-plane spin texture, we demonstrate spin injection from GaAs to TI and its significant contribution to the surface current, which can be manipulated by an external magnetic field. These discoveries pave the way to not only intriguing new physics but also enriched spin functionalities by integrating TI with conventional semiconductors, such that spin-enabled optoelectronic devices may be fabricated in such hybrid structures. [ABSTRACT FROM AUTHOR]