In recent years the emerge of high-entropy alloys (HEAs) imposes an evolution in metallic materials, which breaks the boundaries set by the traditional alloys. Alongside the development of HEAs, the ...medium-entropy alloys (MEAs), which comprise two to four majority elements, also reveal the outperforming properties with less compositional complexity. Among them, the medium-entropy AlNbV alloys attract great attention owing to the existence of a body-centered cubic (BCC) solid solution that contains soluble Al, Nb, and V elements. Herein, we construct the phase diagrams for Al-Nb-V system and define the equilibrium homogeneity by thermally-equilibrated ternary alloys underwent a post-annealing at 1073 K or 1273 K. Meanwhile, a superposition of phase diagram and thermal conductivity κ mapping suggests that the coexistence of BCC solid solution and nano-grained AlNb2 brings down the κ. With the incorporation of Ti and Cr, the HEA AlNbVCrTi, which is composed of Laves C14 phase and BCC solid solution, achieves an ultralow κ of 6–10 Wm−1K−1 within 323–723 K.
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A direct insulator-quantum Hall (I-QH) transition corresponds to a crossover/transition from the insulating regime to a high Landau level filling factor ν > 2 QH state. Such a transition has been ...attracting a great deal of both experimental and theoretical interests. In this study, we present three different two-dimensional electron systems (2DESs) which are in the vicinity of nanoscaled scatterers. All these three devices exhibit a direct I-QH transition, and the transport properties under different nanaoscaled scatterers are discussed.
Abstract
Regulatory T cells have been shown to highly infiltrate the H. pylori-infected gastric mucosa. Treg cells suppress the host’s immune responses to H. pylori and dominate during persistent ...infection. H. pylori-derived HSP60 is one important virulence factor that promotes malignant tumorigenesis. This study further investigated the role of HpHSP60 in immunosuppression, and its activity was found to correlate with the induction of Treg cells. To determine the effects of HpHSP60 on immunosuppression, human peripheral blood mononuclear cells were treated with or without HpHSP60 in the presence of anti-CD3 mAb to determine the effect of HpHSP60 on proliferation. We subsequently asked whether proliferative inhibition correlates with the induction of Treg cells. Finally, the mechanism through which HpHSP60 induces Treg cells was identified. HpHSP60 decreased the expression of CDK4 to significantly slow the proliferation of mitogen-stimulated T cells, which correlated with the induction of Treg cells. Moreover, secretion of IL-10 and TGF-β by monocytic cells was essential to the induction of HpHSP60-induced Treg cells. In summary, we propose that HpHSP60 can act on macrophages to trigger the expression of IL-10 and TGF-β, resulting in an increase in Treg cells and the proliferative inhibition of T cells.
Abstract Background Examinations are necessary for assessment of student proficiency in medical education, but comparison of achievement across different cohorts in different tests is challenging. We ...applied psychometric test equating methods to compare student proficiency in two different examinations for a clinical anesthesiology course. Methods Each examination contained 50 multiple choice items and nine common items were identified from the two examinations (administered in 2011 and 2012). The common item design was used for test equating. Two psychometric test-equating approaches, chained linear equating and item response theory, were used to compare student proficiency in anesthesiology across distinct medical student cohorts. Raw scores from the 2012 test were linearly transformed to the 2011 scale using the chained method, and then Rasch analysis was applied to calibrate examinee ability and item difficulty in the two examinations on a common scale. Results Both the linear equating method and Rasch analysis indicated that students in the 2011 examination performed better than those who took the 2012 examination (both p < 0.001). Rasch analysis revealed that the range of student ability was between −0.53 and 4.16, while the difficulty of all items ranged from −5.25 to 6.32. No significant difference in mean item difficulty was noted among the common items and other items in the two examinations. Conclusion Although both the chained linear equating method and Rasch analysis can be readily applied to practical test-equating issues in medical education, Rasch analysis exhibited more versatility in test parameter estimation and item bank development for clinical curriculums.
Imatinib combined with chemotherapy for induction and intensification therapy has become the standard strategy for Philadelphia-positive acute lymphocytic leukemia (Ph+ALL). Anyhow, intensified ...chemotherapy lead to about 5% of early death. Because we believed that imatinib plays the most important role in Ph+ALL treatment, we started Ph+ALL-HX-200803 trial (WHO ICTRP Registry No. ChiCTR-TNRC-00000309 ) to test the effect of combining imatinib and low dose chemotherapy and added interferon-¦Á in maintenance to prevent relapse.
According to our protocol, all patients received imatinib 400mg daily, vindesine 4 mg weekly and dexamethasone 10mg/m2/day for 4 days per week for 4 weeks as induction therapy. For patients under 55 years old, we give them three sequential courses of intensified chemotherapy (CAM, high dose MTX+L-Asp, and MA, CALLG2008 protocol). Patients in CR1 would receive allogenic HSCT if they had suitable donors. Those who were reluctant to receive or unsuitable for allo-HSCT received maintenance therapy with imatinib 400mg daily, interferon-¦Á 3 million unit 2-3 doses per week and chemotherapy. Maintenance chemotherapy including vindesine and dexamethasone was given monthly in the first year, once every two months in the second year, and once every three months in the third year. For patients over 55 years old, we skipped intensified chemotherapy and gave them maintenance therapy directly. Minimal residual disease surveillance was conducted by BCR/ABL fusion gene quantification. The main endpoints were 3-year overall survival and disease free survival.
Between 2008 and 2012, 50 patients with newly diagnosed Ph+ALL were enrolled. The median age of this group of patients was 35.5 years old. All but one patients achieved complete remission (98%) after 4 weeks induction therapy. No patient died during induction therapy. The median follow-up time was 27 months. The estimated 3-year DFS and OS were 38.8 ±9.2% and 52.7±10.4%. Five patients received allo-HSCT in CR1. For patients who did not receive allo-HSCT in CR1, 1 patient survived for more than 5 years, 7 patients survived for more than 3 years. In post-hoc analysis, patients achieved MRD negativity at six month showed better median DFS (not reached vs. 11 moths, p=0.001) and OS (not reached vs. 22 months, p=0.015) compared to those who did not.
The outcomes of our study suggest that imatinib combing with low dose chemotherapy showed a high and safe induction remission rate, combination of interferon-¦Á with imatinib and maintenance chemotherapy might improve the outcomes of patients with Ph+All who were not eligible for Allo-HSCT. MRD status at six month is an important prognostic indicator. The long term disease-free survivors may signal the possibility of a cure even without allo-HSCT.
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No relevant conflicts of interest to declare.
In the context of white dwarf asteroseismology, we investigate the vibrational properties of a non-convective solid star with an axisymmetric purely toroidal intrinsic magnetic field of two different ...shapes. Focus is laid on the regime of node-free global Lorentz-force-driven vibrations about the symmetry axis at which material displacements have one and the same form as those for nodeless spheroidal and torsional vibrations restored by Hooke’s force of elastic shear stresses. Particular attention is given to the even-parity poloidal Alfvén modes whose frequency spectra are computed in analytic form, showing how the purely toroidal magnetic fields completely buried beneath the star surface can manifest itself in seismic vibrations of non-magnetic white dwarfs. The spectral formulae obtained are discussed in juxtaposition with those for Alfvén modes in the solid star model with the poloidal, homogeneous internal and dipolar external, magnetic field whose inferences are relevant to Alfvén vibrations in magnetic white dwarfs.
TCF7L2
genetic variants were associated with progression to type 2 diabetes in Europeans. However, the role of
TCF7L2
in type 2 diabetes remained uncertain in Chinese. Seventeen tag single nucleotide ...polymorphisms were genotyped in 1,094 subjects of Chinese origin from the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance family study. At baseline, the rs7903146 T allele in the exon 4 linkage disequilibrium (LD) block were associated with lower insulinogenic index at 60 min (
P
= 0.01), while the rs290481 G allele near the 3′ end was associated with higher 2-h post-challenge glucose (
P
= 0.003) and insulin concentration (
P
= 0.02), elevated systolic (
P
= 0.01) and diastolic blood pressure (
P
= 0.006), lower waist circumference (
P
= 0.01), and increased steady-state plasma glucose (SSPG) concentration measured with modified insulin suppression test (
P
= 0.02). Over an average follow-up period of 5.43 years, participants with the rs7903146 T allele or variants in the same LD block, but not those with the rs290481 G allele, were more likely to progress to diabetes (hazard ratio = 2.61, 95% confidence interval, 1.27–5.39,
P
= 0.009) than were non-carriers.
TCF7L2
gene expression was inversely associated with SSPG in human visceral (
r
= −0.73,
P
= 0.006) and subcutaneous adipose tissue (
r
= −0.62,
P
= 0.03).
TCF7L2
may exert pleiotropic effects on insulin secretion or insulin resistance. However, only variants associated with impaired β-cell function predict progression to diabetes in Chinese.
The accurate identification of potential poly(A) sites has contributed to all many studies with regard to alternative polyadenylation. The aim of this study was the development of a machine-learning ...methodology that will help to discriminate real polyadenylation signals from randomly occurring signals in genomic sequence. Since previous studies have revealed that RNA secondary structure in certain genes has significant impact, the authors tried to computationally pinpoint common structural patterns around the poly(A) sites and to investigate how RNA secondary structure may influence polyadenylation. This involved an initial study on the impact of RNA structure and it was found using motif search tools that hairpin structures might be important. Thus, it was propose that, in addition to the sequence pattern around poly(A) sites, there exists a widespread structural pattern that is also employed during human mRNA polyadenylation. In this study, the authors present a computational model that uses support vector machines to predict human poly(A) sites. The results show that this predictive model has a comparable performance to the current prediction tool. In addition, it was identified common structural patterns associated with polyadenylation using several motif finding programs and this provides new insight into the role of RNA secondary structure plays in polyadenylation.
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