Superconductivity in kagome metal ThRu_(3)Si_(2)

We report the physical properties of ThRu_(3)Si_(2)featured with distorted Ru kagome lattice.The combined experiments of resistivity,magnetization and specific heat reveal bulk superconductivity with T_(c)=3.8 K.The specific heat jump and calculated electron–phonon coupling indicate a moderate coupled BCS superconductor.In comparison with LaRu_(3)Si_(2),the calculated electronic structure in ThRu_(3)Si_(2)shows an electron-doping effect with electron filling lifted from 100 meV below flat bands to 300 meV above it.This explains the lower superconducting transition temperature and weaker electron correlations observed in ThRu_(3)Si_(2).Our work suggests the Tc and electronic correlations in the kagome superconductor could have an intimate connection with the flat bands.

Achieving laparoscopic anatomic resection for hepatocellular carcinoma by fluorescence guided positive staining of hepatic cone unit

Laparoscopic anatomical liver resection has been increasingly reported worldwide,but how to demarcate the resection planes is technically challenging[1].Positive staining technique with intraoperative indocyanine green(ICG)-fluorescence imaging has been introduced as an effective tool for real-time intraoperative guidance[2].Liver anatomy is complex.Generally,liver is composed of 9 segments,each is composed of two to three subsegments,and each subsegment contains several hepatic cone units.A hepatic cone unit is dominated by a tertiary or quaternary hepatic pedicles[3].

450 nm半导体蓝激光对子宫内膜组织汽化切割效应的离体动物实验研究

目的使用450 nm半导体蓝激光手术系统在不同条件下对离体新鲜猪子宫内膜组织进行汽化切割及内镜下模拟手术实验,初步评估蓝激光在妇科手术应用中的安全性、有效性和可行性。方法取产后和未孕新鲜猪离体子宫各8个,使用450 nm纤芯光纤,步进机移动速度为1.0 mm/s、2.0 mm/s,光纤头距离组织0.5~1.0 mm,调试蓝激光功率为5~30 W等条件下对猪子宫内膜组织进行汽化切割,对汽化切割后的标本行拍照记录后,置入4%多聚甲醛内固定48小时,使用游标卡尺测量凝固范围、汽化宽度、汽化深度,将标本行HE染色。使用产后子宫8个,对比等离子电切设备,在体外内镜辅助下进行模拟手术操作,将术后的标本行HE染色。结果激光在不同的功率(5~25 W)下作用于子宫内膜组织,随着激光功率的增大,组织的汽化深度、汽化宽度也逐渐增大;使用双极等离子电切设备与蓝激光在内镜下行汽化切割实验的比较,结果发现蓝激光汽化切割创面更平整,无明显碳化层,热损伤范围局限可控,凝固层、汽化深度及宽度稳定。相较于等离子电切设备,蓝激光产生的热损伤范围相对较小。结论初步研究表明,蓝激光进行猪子宫内膜相关手术是安全、有效且可行的,并且有望成为可选择的一种新型的妇科激光手术设备。

A new preparation technology of structural- gradient materials without a brittle transition zone in a Mn-Si-Cr-B bainitic cast steel

In the present work, a unique gradient cooling heat treatment process(GCHT) for a Mn-Si-Cr-B bainitic cast steel was developed, and microstructure and mechanical properties were examined by OM, SEM, EBSD and a uniaxial tensile test. The results showed that the structural-gradient-material(SGM) with a gradient microstructure from granular bainite to martensite was successfully produced, and it exhibited a good ductility(~13.8%) at one end and an excellent ultimate strength(~1,720 MPa) at the other end. In between the bainite and martensite, a transition region with a superior combination of tensile strength and ductility(1,700 MPa and 11.1%) was obtained, which is different from the normal knowledge of a brittle transition region. Moreover, through changing the gradient of cooling rate, the optimized SGM with a new gradient microstructure from pearlite to martensite showed a more stable structural gradient and an improved ductility(22.8%) at one end. The microstructure variation in the sample was mainly related to the carbon diffusion rate during heat treatment, and the diffusion rate could be controlled by regulating the cooling velocity. Therefore, the SGMs with different gradient microstructures could be designed to meet the needs of different properties. As a result, this work provides a new approach for preparation of the gradient structured steel, which has potential for practical application for dual-property automobile parts.

睑缘炎相关角结膜病变的诊断和治疗研究进展

睑缘炎相关角结膜病变(blepharokeratoconjunctivitis),简称为BKC,是指一类继发于睑缘炎的慢性角结膜炎性病变^([1]),在临床上是一类常见的疾病,同时也是一类容易被误诊、漏诊的疾病,导致延误治疗。病情迁延不愈或不合理的治疗可造成患者不可逆的视功能损害。近年来,随着人们对眼表疾病的认识不断加深,对BKC的重视度越来越高,临床上对其诊治进行了大量的探讨,但目前还未形成统一的诊治标准。针对现状,查阅相关文献,本文对BKC的诊断和治疗做一综述。

良性前列腺增生经尿道前列腺等离子电切术临床路径释义

良性前列腺增生是引发中老年男性排尿功能障碍最为常见的一种良性疾病,也是导致下尿路症状的主要原因。经尿道前列腺等离子电切术效果好、安全可靠,已在临床中广泛应用。为进一步规范该手术的临床应用,国家卫生健康委员会于2019年首次发布了《良性前列腺增生经尿道前列腺等离子电切术临床路径》。鉴于临床路径的篇幅有限,本文以该路径为蓝本,遵照循证医学的思路与方法进行释义,旨在提供更为详尽的证据补充,以帮助医护人员和管理人员能更好地理解、把握和正确运用本临床路径。

膀胱肿瘤经尿道等离子电切术临床路径释义

膀胱癌是全球第十大最常被诊断出的癌症,在男性中更常见。经尿道膀胱肿瘤电切术既是膀胱肿瘤的重要诊断方法,也是非肌层浸润性膀胱癌的主要治疗手段。相较于传统单极电切,等离子双极电切具有手术效果好、并发症较少的优势,临床应用渐趋广泛。为规范常见病的诊疗,国家卫健委持续发布相关的临床路径,但临床路径的内容有限,对其进行释义可以更好的推广使用。本释义以最新发布的《膀胱肿瘤经尿道等离子电切术临床路径(2019年版)》为蓝本,采用循证医学的方法,对路径中涉及的给药方案进行了详细解读,以期为医护及管理人员能够更好地理解、把握和正确运用临床路径提供参考。

Active metasurfaces for manipulatable terahertz technology

Metasurface is a kind of two-dimensional metamaterial with specially designed sub-wavelength unit cells.It consists of single-layer or few-layer stacks of planar structures and possesses certain superior abilities to manipulate the propagating electromagnetic waves,including the terahertz(THz)ones.Compared with the usual passive THz metasurfaces whose optical properties are difficult to be controlled after fabrication,the active materials are highly desirable to enable dynamic and tunable control of THz waves.In this review,we briefly summarize the progress of active THz metasurfaces,from their physical mechanisms on carrier concentration modulations,phase transitions,magneto-optical effects,etc.,for various possible THz applications mainly with low-dimensional materials,vanadium dioxide films,and superconductors.

Global,regional,and national burden of kidney,bladder,and prostate cancers and their attributable risk factors,1990–2019

Background:The burden of kidney,bladder,and prostate cancers has changed in recent decades.This study aims to investigate the global and regional burden of,and attributable risk factors for genitourinary cancers during the past 30 years.Methods:We extracted data of kidney,bladder,and prostate cancers from the Global Burden of Disease 2019 database,including incidence,mortality,disability-adjusted life-years(DALYs),and attributable risk factors from 1990 to 2019.Estimated annual percentage changes(EAPC)were calculated to assess the changes in age-standardized incidence rate,age-standardized mortality rate(ASMR),and age-standardized DALYs rate(ASDR).The associations between cancers burden and socio-demographic index(SDI)were also analyzed.Results:Compared with 1990,the global incident cases in 2019 were higher by 154.78%,123.34%,and 169.11%for kidney,bladder,and prostate cancers,respectively.During the 30-year study period,there was a downward trend in ASMR and ASDR for bladder cancer(EAPC=–0.68 and–0.83,respectively)and prostate cancer(EAPC=–0.75 and–0.71,respectively),but an upward trend for kidney cancer(EAPC=0.35 and 0.12,respectively).Regions and countries with higher SDI had higher incidence,mortality,and DALYs for all three types of cancers.The burden of bladder and prostate cancers was mainly distributed among older men,whereas the burden of kidney cancer increased among middle-aged men.Smoking related mortality and DALYs decreased,but high body mass index(BMI)and high fasting plasma glucose(FPG)related mortality and DALYs increased among kidney,bladder,and prostate cancers during the study period.Conclusions:Kidney,bladder,and prostate cancers remain major global public health challenges,but with distinct trend for different disease entity across different regions and socioeconomic status.More proactive intervention strategies,at both the administrative and academic levels,based on the dynamic changes,are needed.

Total saponins in Rubus parvifolius L.induce lymphoma cells apoptosis through upregulated Bax/Fas and downregulated Bcl-2 in vivo and in vitro

Purpose:To investigate the effect of total saponins of Rubus parvifolius L.(TSRP)on lymphoma Raji cells and further discuss its mechanism.Methods:The model of nude mice bearing Raji cells was established,the volume,weight and inhibition rate of the transplanted tumor were analyzed and compared after different concentrations of TSRP treatment.Cell apoptosis and expression of Bcl-2,Bax,Fas proteins were detected by TUNEL and immunohistochemiscal method respectively.Effects of TSRP on cell proliferation were tested with MTT assay in vitro.Cell apoptosis and expression of Caspase-9,Caspase-3,Bcl-2,Bax and Fas proteins were tested with DAPI staining and Western blot.Results:TSRP significantly reduced the volume and tumor weight of Raji subcutaneous transplanted tumor and induced the apoptosis of Raji cells in vivo.The tumor inhibition rate of high-dose(100 mg/kg)TSRP is 90.84%.The TUNEL test results show that the fluorescence intensity of the tumor issue treated with TSRP is significantly improved.Compared with the control group,the fluorescence intensity of high-concentration TSRP is 82.43 ± 7.81,which is significantly different(P<0.001).The results of immunohistochemistry test showed that the Bcl-2 expression of Raji cell treated with TSRP is obviously reduced,and Bax expression is obviously increased.Meanwhile,compared with that of control group,Fas expression is obviously reduced.MTT assay showed that TSRP can significantly inhibit proliferation of Raji cells with dose dependence.The inhibition rate of 400 μg/mL TSRP is 53.46 ± 4.90%(P<0.001).DAPI staining results showed that TSRP can significantly induce cell apoptosis.According to Western blot results,it is found that TSRP can significantly inhibit activity of Bcl-2 and increase Bax expression,and TSRP can also inhibit Fas expression.Meanwhile,expression of Caspase-9 and Caspase-3 is also increased.Conclusion:TSRP could inhibit the proliferation of lymphoma via induction of apoptosis in a time and dose-dependent manner.Apoptotic signaling induced by TSRP was characterized by up-regulating Bax,Fas and Caspase-8 protein expression,and down-regulating of Bcl-2 protein expression.

Superconducting Properties and Absence of Time Reversal Symmetry Breaking in the Noncentrosymmetric Superconducting Compounds Ta_(x)Re_(1-x)(0.1≤x≤0.25)

Unconventional superconductivity,in particular,in noncentrosymmetric systems,has been a long-sought topic in condensed matter physics.Recently,Re-based superconductors have attracted great attention owing to the potential time-reversal symmetry breaking in their superconducting states.We report the superconducting properties of noncentrosymmetric compounds Ta_(x)Re_(1-x) with 0.1 ≤x≤0.25,and find that the superconducting transition temperature reaches a maximum of ~8 K at the optimal level x=0.15.Nevertheless,muon-spin rotation and relaxation measurements reveal no time-reversal symmetry breaking existing in its superconducting state,which is in sharp contrast to both centrosymmetric Re metal and many other noncentrosymmetric Re-based superconductors.

Anisotropic transport in a possible quasi-one-dimensional topological candidate:TaNi_(2)Te_(3)

We report on the solid-state synthesis and the strongly anisotropic transport properties of the ternary telluride TaNi_(2)Te_(3),whose three orthogonal resistivity coefficients exhibit a large ratio of 1.4:1:2294(14:1:2303) at 300 K(2 K),thereby demonstrating its quasi-one-dimensional(q1D) electronic structure.The Kohler’ s rule in different current/field configurations shows a moderate violation.Its one dimensionality manifests itself in the needle-like shape of crystal,the large anisotropic resistivity and the flat Fermi surface normal to the chain direction.Moreover,the first-principles calculations also provide evidence for the existence of the nontrivial topological carriers in this q1D system.Our calculation demonstrates that TaNi_(2)Te_(3) is a strong topological nontrivial material with topological indices(1;1 0 1) and its nontrivial topology is also evidenced from its bulk-surface correspondence.Our study may therefore offer a new platform for engineering the topologically nontrivial phase in low-dimensional materials,in analogy to the recently discovered q1D topological TaNiTe_(5).

脂肪腈的合成方法及规模化制备进展

脂肪腈类化合物是重要的化工原料和合成中间体,广泛应用于材料和药物合成等领域.本文综述了脂肪腈合成方法学的研究进展,包括对烷烃、烯烃、醛醇和胺类底物的氧化腈化,采用氰基源为反应试剂对烷烃、卤代烷烃、烯烃类底物的直接氰化,以及对酰胺、羧酸(酯)和醛肟底物的脱水腈化.同时,以丙烯腈、己二腈和乙腈为典型代表,概述了相关规模化制备的技术进展和主要问题,并展望了脂肪腈合成与规模制备的未来发展方向.

1990~2017年中国膀胱癌疾病负担分析

目的分析1990~2017年中国膀胱癌疾病负担的变化趋势。方法利用2017年全球疾病负担研究结果,采用膀胱癌发病率、死亡率、伤残调整寿命年(Disability-adjusted life year,DALY)、过早死亡损失寿命年(Years of life lost,YLL)、伤残损失寿命年(Years lived with disability,YLD)及其标化率对1990年和2017年间中国人群膀胱癌疾病负担情况进行描述。结果2017年中国膀胱癌发病例数为7.30万,标化发病率为3.89/10万,死亡例数为3.06万,标化死亡率为1.75/10万。与1990年相比,发病例数增加了164.49%,标化发病率增加了15.09%,死亡例数增加了92.45%,标化死亡率降低了23.58%。男性的发病率和死亡率要高于女性,并且随年龄的增加呈现上升趋势。相比1990年,2017年我国膀胱癌的DALY标化率降低了26.35%,YLL标化率降低了28.59%,YLD标化率增加了28.83%。1990~2017年,我国膀胱癌DALY率整体呈下降趋势,但男性DALY率仍高于女性。结论1990~2017年我国膀胱癌的标化发病率不断上升,标化死亡率呈下降趋势,男性和老年人群是膀胱癌疾病负担的高危人群。

Arabidopsis AT-hook Protein TEK Positively Regulates the Expression of Arabinogalactan Proteins for Nexine Formation

Nexine is a conserved layer of the pollen wall. We previously reported that the nexine layer is absent in the knockout mutant of Arabidopsis TRANSPOSABLE ELEMENT SILENCING VIA AT-HOOK （TEK） gene. In this study, we investigated the molecular regulatory functions of TEK in pollen development and identified the genes encoding Arabinogalactan proteins （AGPs） as direct targets of TEK, which are essential for nexine formation. Phenotypic similarity between tek and the TEK-SRDX transgenic lines suggest that TEK plays a role in transcriptional activation in anther development. Microarray analysis identified a total of 661 genes downregulated in tek, including four genes encoding AGPs, AGP6, AGP11, AGP23, and AGP40. Electrophoretic mobility shift assays showed that TEK could directly bind the nuclear matrix attachment region （MAR） and the promoter of AGP6. Chromatin immunoprecipitation followed by PCR analysis demonstrated that TEK is enriched in the promoters of the four AGP genes. Expression of AGP6 driven by the TEK promoter in tek partially rescued both nexine formation and plant fertility. These results indicate that TEK directly reg- ulates AGP expression in the anther to control nexine layer formation. We also proposed that glycoproteins might be essential components of the nexine laver in the oollen wall.

Austenite Grain Refinement by Reverse α′→γ Transformation in Metastable Austenitic Manganese Steel

Microstructure of metastable austenitic manganese steel after reverse transformation treatment was investi gated using optical microscopy, X ray diffraction （XRD）, electrical resistivity and hardness testing. Austenite grain refinement was successfully achieved by a two-step heat treatment. First, martensite was produced by cooling the so- lution-treated samples to --196 ℃. Then, the deep cryogenic treated samples were heated to 850 ℃ upon slow or rapid heating. The mean size of original austenite grain was about 400 fire. But the mean size of equiaxed reversion austenite was refined to 50 μm. Microstructure evolution and electrical resistivity change showed that martensite plates underwent tempering action upon slow heating, and the residual austenite was decomposed, resulting in the formation of pearlite nodules at the austenite grains boundaries. The refinement mechanism upon slow heating is the diffusion-controlled nucleation and growth of austenite. However, the reverse transformation upon rapid heating was predominated by displacive manner. The residual austenite was not decomposed. The plate α-phase was carbon-super- saturated until the starting of reverse transformation. The reverse transformation was accompanied by surface effect, resulting in the formation of plate austenite with high density dislocations. The refinement mechanism upon rapid heating is the recrystallization of displacive reversed austenite.

Delayed callose degradation restores the fertility of multiple P/TGMS lines in Arabidopsis

Photoperiod/temperature-sensitive genic male sterility(P/TGMS)is widely applied for improving crop production.Previous investigations using the reversible male sterile(rvms)mutant showed that slow development is a general mechanism for restoring fertility to P/TGMS lines in Arabidopsis.In this work,we isolated a restorer of rvms–2(res3),as the male sterility of rvms–2 was rescued by res3.Phenotype analysis and molecular cloning show that a point mutation in UPEX1 l in res3 leads to delayed secretion of callase A6 from the tapetum to the locule and tetrad callose wall degradation.Electrophoretic mobility shift assay and chromatin immunoprecipitation analysis demonstrated that the tapetal transcription factor ABORTED MICROSPORES directly regulates UPEX1 expression,revealing a pathway for tapetum secretory function.Early degradation of the callose wall in the transgenic line eliminated the fertility restoration effect of res3.The fertility of multiple known P/TGMS lines with pollen wall defects was also restored by res3.We propose that the remnant callose wall may broadly compensate for the pollen wall defects of P/TGMS lines by providing protection for pollen formation.A cellular mechanism is proposed to explain how slow development restores the fertility of P/TGMS lines in Arabidopsis.

Phase diagram and transport properties of Sb-doped Ca0.88La0.12Fe2As2 single crystals

The effects of isovalent Sb substitution on the superconducting properties of the Ca0.88La0.12Fe2（As1-ySby）2 system have been studied through electrical resistivity measure- ments. It is seen that the antiferromagnetic or structural transition is suppressed with Sb content, and a high-To superconducting phase, accompanied by a low-Tc phase, emerges at 0.02 ≤y ≤ 0.06. In this intermediate-doping regime, normal-state transport shows non-Fermi-liquid-like behaviors with nearly T-linear resistivity above the high-Tc phase. With further Sb doping, this high-Tc phase abruptly vanishes for y 〉 0.06 and the conventional Fermi liquid is restored, while the low-T,, phase remains robust against Sb inlpurities. The coincidence of the high-Tc phase and non-Fermi liquid transport behaviors in the intermediate Sb-doping regime suggests that AFM fluctuations play an important role in the observed non-Fermi liquid behaviors, which may be intimately related to the unusual nonbulk high-Tc phase in this system.