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 s...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.展开更多
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 gree...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].展开更多
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 uniaxia...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.展开更多
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 ...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.展开更多
Given the challenges facing the cyberspace of the nation, this paper presents the tripartite theory of cyberspace, based on the status quo of cyberspace. Corresponding strategies and a research architecture are propos...Given the challenges facing the cyberspace of the nation, this paper presents the tripartite theory of cyberspace, based on the status quo of cyberspace. Corresponding strategies and a research architecture are proposed for common public networks （C space）, secure classified networks （S space）, and key infras- tructure networks （K space）, based on their individual characteristics. The features and security require- ments of these networks are then discussed. Taking C space as an example, we introduce the SMCRC （which stands for ＂situation awareness, monitoring and management, cooperative defense, response and recovery, and countermeasures and traceback＂） loop for constructing a cyberspace security ecosys- tem. Following a discussion on its characteristics and information exchange, our analysis focuses on the critical technologies of the SMCRC loop. To obtain more insight into national cyberspace security, special attention should be paid to global sensing and precise mapping, continuous detection and active manage- ment, cross-domain cooperation and systematic defense, autonomous response and rapid processing, and accurate traceback and countermeasure deterrence.展开更多
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 durin...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.展开更多
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,we...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.展开更多
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 poten...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.展开更多
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...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).展开更多
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...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。展开更多
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 i...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.展开更多
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. Austen...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.展开更多
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 gen...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.展开更多
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 antiferromagne...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.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12050003,12004337,and 12274369)the Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ21A040011)。
文摘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.
基金from Health Commission of Zhejiang Province(JBZX-202004)the National Natural Science Foundation of China(82002925)the National Key Research and Development Program of China(2022YFC2407304).
文摘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].
基金financially supported by the National key research and development program(No.2017YFA0403700)the Natural Science Foundation of China(No.51701080)
文摘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.
基金Project supported by the National Natural Science Foundation of China(Grant No.11974290)the Fundamental Research Funds for the Central Universities,China(Grant No.2232020D-44).
文摘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.
文摘Given the challenges facing the cyberspace of the nation, this paper presents the tripartite theory of cyberspace, based on the status quo of cyberspace. Corresponding strategies and a research architecture are proposed for common public networks （C space）, secure classified networks （S space）, and key infras- tructure networks （K space）, based on their individual characteristics. The features and security require- ments of these networks are then discussed. Taking C space as an example, we introduce the SMCRC （which stands for ＂situation awareness, monitoring and management, cooperative defense, response and recovery, and countermeasures and traceback＂） loop for constructing a cyberspace security ecosys- tem. Following a discussion on its characteristics and information exchange, our analysis focuses on the critical technologies of the SMCRC loop. To obtain more insight into national cyberspace security, special attention should be paid to global sensing and precise mapping, continuous detection and active manage- ment, cross-domain cooperation and systematic defense, autonomous response and rapid processing, and accurate traceback and countermeasure deterrence.
文摘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.
文摘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.
基金Supported by the National Key R&D Program of China(Grant No.2018YFA0704300)the National Natural Science Foundation of China(Grant Nos.U1732162,11974061,11704047,U1832147 and 11674054)the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB25000000)。
文摘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.
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 11974061, U1732162, and U1832147)the financial support from the Zhejiang Provincial Natural Science Foundation of China (Grant No. LY19A040002)+3 种基金NUPTSF (Grant Nos. NY219087 and NY220038)the financial support from the Ministry of Science and Technology in Taiwan,China under Project MOST-108-2112-M-001-049-MY2Academia Sinica for the budget of ASi MATE-109-13financial support from the start-ups at Michigan State University。
文摘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).
文摘目的分析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。
文摘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.
基金Sponsored by National Natural Science Foundation of China(51071075)
文摘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.
基金supported by grants from the National Natural Science Foundation of China(31930009,31900260)the Shanghai Municipal Education Commission(2019-01-07-00-02-E00006)the Science and Technology Commission of Shanghai Municipality(18DZ2260500 and 17DZ2252700)。
文摘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.
基金This work was supported by tile National Natural Science Foundation of China （Grant Nos. U1432135, 11674054, 11474080, and 11611140101） and the Scientific Research Foundation of Graduate School of Southeast University （Grant No. YBJJ1621）. X. Xu would also like to acknowledge the National Key Basic Research Program of China （Grant No. 2014CB648400） and the support from the Distinguished Young Scientist Funds of Zhejiang Province （No. LR14A040001）.
文摘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.
