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1Multiple genetic alterations and behavior of cellular biology in gastric cancer and other gastric mucosal lesions:H.pylori infection,histological types and staging显示文摘AIM To investigate the expression of multiplegenes and the behavior of cellular biology ingastric cancer(GC)and other gastric mucosallesions and their relations to Helicobacter pylori(H.pylori)infection,tumor staging andhistological subtypes.METHODS Three hundred and twenty-sevenspecimens of gastric mucosa obtained viaendoscopy or surgical resection,and ABCimmunohistochemical staining were used todetect the expression of p53,p16,Bcl-2 andCOX-2 proteins.H.pylori was determined byrapid urea test combined with pathologicalstaining or14C urea breath test.Cellular image analysis was performed in 66 patients withintestinal metaplasia(IM)and/or dysplasia(Dys).In 30 of them,both cancer and theparacancerous tissues were obtained at the timeof surgery.Histological pattern,tumor staging,lymph node metastasis,grading ofdifferentiation and other clinical data werestudied in the medical records.RESULTS p16 expression of IM or Dys wassignificantly lower in positive H.pylori chronicatrophic gastritis(CAG)than those withnegative H.pylori(CAG:54.8% vs 88.0%,IM:34.4% vs 69.6%,Dys:23.8% vs 53.6%,allP<0.05),Bcl-2 or COX-2 expression of IM orDys in positive H.pylori cases was significantlyhigher than that without H.pylori(Bcl-2:68.8%vs23.9%,90.5% vs 60.7%;COX-2:50.0% vs10.8%,61.8% vs 17.8%;all P<0.05).Themean number of most parameters of cellularimage analysis in positive H.pylori group wassignificantly higher than that in negative H.pylori group(Ellipser:53±14,40±12μm,Area1:748±572,302±202 μm2,Area2:3050±1661,1681±1990 μm2,all P<0.05;Ellipseb:79±23,58±15 μm,Ratio1:22%±5%,13%±4%,Ratio2:79%±17%,53%±20%,all P<0.01).There was significant correlation between Bcl-2and histologic pattern of gastric carcinoma,andbetween COX-2 and tumor staging or lymph nodemetastasis(Bcl-2:75.0% vs 16.7%;COX-2:76.0% vs 20.0%,79.2% vs 16.7%;allP<0.05).CONCLUSION p1l6, Bcl-2, and COX-2 but not p53 gene may play a role in the early genesis/ progression of gastric carcinoma and are associated with H. pylori infection. p53 gene is relatively late event in gastric tumorigenesis and mainly relates to its progression. There is more cellular-biological behavior of malignant tumor in gastric mucosal lesions with H. pylori infection. Aberrant Bcl-2 protein expression appears to be preferentially associated with the intestinal type cancer. COX-2 seems to be related to tumor staging and lymph node metastasis.Heng Jun Gao Lian Zhen Yu Jian Feng Bai Yan Shen Peng Gu Sun Han Lin Zhao Kun Miu Xiu Zhen Lü Xiao Yong Zhang Zhi Quan Zhao 2000World Journal of Gastroenterology2000,6,6:52
2High entropy defective fluorite structured rare-earth niobates and tantalates for thermal barrier applications显示文摘Rare-earth tantalates and niobates(REjTaO7 and REjNbO7)have been considered as promising candidate thermal barrier coating(TBC)materials in next generation gas-turbine engines due to their ultra-low thermal conductivity and better thermal stability than yttria-stabilized zirconia(YSZ).However,the low Vickers hardness and toughness are the main shortcomings of RE;TaO-and REjNbOr that limit their applications as TBC materials.To increase the hardness,high entropy(Yu3Ybu3Er/3)sTaOr,(Y13YbnErns)NbO,and(Sm1/6Eu1/6Y 1/6Yb1/6Lu1/6Er1/6)3(Nb1/2Ta1/2)O7 are designed and synthesized in this study.These high entropy ceramics exhibit high Vickers hardness(10.912.0 GPa),close thermal expansion coefficients to that of single-principal-component RE3TaO,and RE;NbO,(7.9×10^-6-10.8×10-6 C-1 at room temperature),good phase stability,and good chemical compatibility with thermally grown Al2O3,which make them promising for applications as candidate TBC materials.Zifan ZHAO Heng CHEN Huimin XIANG Fu-Zhi DAI Xiaohui WANG Wei XU Kuang SUN Zhjjian PENG Yanchun ZHOU 2020Journal of Advanced Ceramics2020,9,3:27
3(La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4: A high-entropy rare-earth phosphate monazite ceramic with low thermal conductivity and good compatibility with Al2O3显示文摘Low thermal conductivity, matched thermal expansion coefficient and good compatibility are general requirements for the environmental/thermal barrier coatings(EBCs/TBCs) and interphases for Al2O3 f/Al2O3 composites. In this work, a novel high-entropy(HE) rare-earth phosphate monazite ceramic (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 is designed and successfully synthesized. This new type of HE rare-earth phosphate monazite exhibits good chemical compatibility with Al2O3, without reaction with Al2O3 as high as 1600℃ in air. Moreover, the thermal expansion coefficient(TEC) of HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4(8.9 × 10^-6/℃ at 300–1000℃) is close to that of Al2O3. The thermal conductivity of HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 at room temperature is as low as 2.08 W·m^-1·K^-1, which is about 42% lower than that of La PO4. Good chemical compatibility, close TEC to that of Al2O3, and low thermal conductivity indicate that HE (La0.2Ce0.2Nd0.2Sm0.2Eu0.2)PO4 is suitable as a candidate EBC/TBC material and an interphase for Al2O3 f/Al2O3 composites.Zifan Zhao Heng Chen Huimin Xiang Fu-Zhi Dai Xiaohui Wang Zhijian Peng Yanchun Zhou 2019Journal of Materials Science & Technology2019,35,12:15
4High-entropy(Nd_(0.2)Sm_(0.2)Eu_(0.2)Y_(0.2)Yb_(0.2))_(4)Al_(2)O_(9) with good high temperature stability,low thermal conductivity,and anisotropic thermal expansivity显示文摘The critical requirements for the environmental barrier coating(EBC)materials of silicon-based ceramic matrix composites(CMCs)include good tolerance to harsh environments,thermal expansion matches with the interlayer mullite,good high-temperature phase stability,and low thermal conductivity.Cuspidine-structured rare-earth aluminates RE_(4)Al_(2)O_(9) have been considered as candidates of EBCs for their superior mechanical and thermal properties,but the phase transition at high temperatures is a notable drawback of these materials.To suppress the phase transition and improve the phase stability,a novel cuspidine-structured rare-earth aluminate solid solution(Nd_(0.2)Sm_(0.2)Eu_(0.2)Y_(0.2)Yb_(0.2))_(4)Al_(2)O_(9) was designed and successfully synthesized inspired by entropy stabilization effect of high-entropy ceramics(HECs).The as-synthesized HE(Nd_(0.2)Sm_(0.2)Eu_(0.2)Y_(0.2)Yb_(0.2))_(4)Al_(2)O_(9) exhibits a close thermal expansion coefficient(6.96×10^(-6) K^(-1) at 300-1473 K)to that of mullite,good phase stability from 300 to 1473 K,and low thermal conductivity(1.50 W·m^(-1)·K^(-1) at room temperature).In addition,strong anisotropic thermal expansion has been observed compared to Y_(4)Al_(2)O_(9) and Yb_(4)Al_(2)O_(9).The mechanism for low thermal conductivity is attributed to the lattice distortion and mass difference of the constituent atoms,and the anisotropic thermal expansion is due to the anisotropic chemical bonding enhanced by the large size rare-earth cations.Zifan ZHAO Huimin XIANG Heng CHEN Fu-Zhi DAI Xiaohui WANG Zhijian PENG Yanchun ZHOU 2020Journal of Advanced Ceramics2020,9,5:12
5Correlation between adult pyrethroid resistance and knockdown resistance(kdr)mutations in Aedes albopictus(Diptera:Culicidae)field populations in China显示文摘Background:Arboviral disease transmitted by Aedes albopictus such as dengue fever is an important threat to human health.Pyrethroid resistance raises a great challenge for mosquito control.A systematic assessment of Ae.albopictus resistance status in China is urgently needed,and the study of correlation between pyrethroid resistance and knockdown resistance(kdr)mutations would provide information to guide the control of the Ae.albopictus vector.Methods:Five field populations of Ae.albopictus were collected from Jinan(JN),Hangzhou(HZ),Baoshan(BS),Yangpu(YP)and Haikou(HK),China in 2017.Insecticide-impregnated papers were prepared with four pyrethroid chemicals,deltamethrin,permethrin,beta-cypermethrin and lambda-cyhalothrin.The susceptibility of Ae.albopictus to pyrethroids was tested by the WHO tube assay.Kdr mutations were identified by PCR and sequencing.Moreover,the correlation analysis between kdr alleles and pyrethroid resistance was performed.Results:All five populations of Ae.albopictus showed resistance to four pyrethroid insecticides.One kdr mutant allele at codon 1532 and three at 1534 were detected with frequency of 5.33%(I1532T),44.20%(F1534S),1.83%(F1534 L)and 0.87%(F1534C),respectively.Both 1532 and 1534 mutation mosquitoes were found in the BS and YP populations.Allele I1532T was negatively correlated with deltamethrin resistance phenotype(OR<1),while F1534S mutation was positively correlated with deltamethrin and permethrin resistance(OR>1).Conclusions:The five field populations of Ae.albopictus adults were all resistant to deltamethrin,permethrin,betacypermethrin and lambda-cyhalothrin.Mutant F1534S was clearly associated with pyrethroid resistance phenotype in Ae.albopictus and this could be developed as a molecular marker to monitor the pyrethroid resistance problem in China.Jing-Peng Gao Han-Ming Chen Hua Shi Heng Peng Ya-Jun Ma 2018Infectious Diseases of Poverty2018,7,1:11
6High-entropy(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3:A promising thermal/environmental barrier material for oxide/oxide composites显示文摘Yttrium aluminum perovskite(YAl O3)is a promising candidate material for environmental barrier coatings(EBCs)to protect Al2 O3 f/Al2 O3 ceramic matrix composites(CMCs)from the corrosion of high-temperature water vapor in combustion environments.Nevertheless,the relatively high thermal conductivity is a notable drawback of YAl O3 for environmental barrier coating application.Herein,in order to make REAl O3 more thermal insulating,a novel high-entropy rare-earth aluminate ceramic(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3 was designed and synthesized.The as-prepared(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3 ceramic possesses close thermal expansion coefficient(9.02×10-6/oC measured from room temperature to 1200℃)to that of Al2 O3.The thermal conductivity of(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3 at room temperature is 4.1 W·m-1K-1,which is almost one third of the value of YAl O3.Furthermore,to effectively prevent the penetration of water vapor from possible pores/cracks of coating layer,which are often observed in T/EBCs,a tri-layer EBC system REAl O3/RE3 Al5 O12/(Al2 O3 f/Al2 O3 CMCs)is designed.Close thermal expansion coefficient to Al2 O3 and low thermal conductivity of(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3,as well as the formation of dense garnet layer at(Y0.2Nd0.2Sm0.2Eu0.2Er0.2)AlO3/Al2 O3 interface,indicate that this new type of high-entropy ceramic is suitable as a candidate environmental barrier coating material for Al2 O3 f/Al2 O3 CMCs.Zifan Zhao Heng Chen Huimin Xiang Fu-Zhi Dai Xiaohui Wang Wei Xu Kuang Sun Zhijian Peng Yanchun Zhou 2020Journal of Materials Science & Technology2020,47,12:9
7Synthesis, isolation and characterization of methyl levulinate from cellulose catalyzed by extremely low concentration acid显示文摘A direct synthesis of methyl levulinate from cellulose alcoholysis in methanol medium under mild condition(180 210 C)catalyzed by extremely low concentration sulfuric acid(0.01 mol/L)and the product isolation were developed in this study.Effects of different process variables towards the catalytic performance were performed as a function of reaction time.The results indicated that sulfuric acid concentration,temperature and initial cellulose concentration had significant effects on the synthesis of methyl levulinate.An optimized yield of around 50%was achieved at 210 C for 120 min with sulfuric acid concentration of 0.01 mol/L and initial cellulose concentration below 100 g/L.The resulting product mixture was isolated by a distillation technique that combines an atmospheric distillation with a vacuum distillation where n-dodecane was added to help distill the heavy fraction.The light fraction including mainly methanol could be reused as the reaction medium without any substantial change in the yield of methyl levulinate.The chemical composition and structural of lower heavy fraction were characterized by GC/MS,FTIR,1H-NMR and13C-NMR techniques.Methyl levulinate was found to be a major ingredient of lower heavy fraction with the content over 96%.This pathway is efficient,environmentally benign and economical for the production of pure levulinate esters from cellulose.Hui Li Lincai Peng Lu Lin Keli Chen Heng Zhang 2013Journal of Energy Chemistry2013,22,6:9
8Retrospective study of effect of whole-body vibration training on balance and walking function in stroke patients显示文摘BACKGROUND Dysfunction in stroke patients has been a problem that we committed to solve and explore.Physical therapy has some effect to regain strength,balance,and coordination.However,it is not a complete cure,so we are trying to find more effective treatments.AIM To observe the effect of whole-body vibration training(WVT)on the recovery of balance and walking function in stroke patients,which could provide us some useful evidence for planning rehabilitation.METHODS The clinical data of 130 stroke participants who underwent conventional rehabilitation treatment in our hospital from January 2019 to August 2020 were retrospectively analyzed.The participants were divided into whole-body vibration training(WVT)group and non-WVT(NWVT)group according to whether they were given WVT.In the WVT group,routine rehabilitation therapy was combined with WVT by the Galileo Med L Plus vibration trainer at a frequency of 20 Hz and a vibration amplitude of 0+ACY-plusmn+ADs-5.2 mm,and in the NWVT group,routine rehabilitation therapy only was provided.The treatment course of the two groups was 4 wk.Before and after treatment,the Berg balance scale(BBS),3 m timed up-and-go test(TUGT),the maximum walking speed test(MWS),and upper limb functional reaching(FR)test were performed.RESULTS After 4 wk training,in both groups,the BBS score and the FR distance respectively increased to a certain amount(WVT=46.08±3.41 vs NWVT=40.22±3.75;WVT=20.48±2.23 vs NWVT=16.60±2.82),with P<0.05.Furthermore,in the WVT group,both BBS score and FR distance(BBS:18.32±2.18;FR:10.00±0.92)increased more than that in the NWVT group(BBS:13.29±1.66;FR:6.16±0.95),with P<0.05.Meanwhile,in both groups,the TUGT and the MWS were improved after training(WVT=32.64±3.81 vs NWVT=39.56±3.68;WVT=12.73±2.26 vs NWVT=15.04±2.27,respectively),with P<0.05.The change in the WVT group(TUGT:17.49±1.88;MWS:6.79±0.81)was greater than that in the NWVT group(TUGT:10.76±1.42;MWS:4.84±0.58),with P<0.05.CONCLUSION The WVT could effectively improve the balance and walking function in stroke patients,which may be good for improving their quality of life.Lei Xie Shi-Xiong Yi Qi-Feng Peng Pei Liu Heng Jiang 2021World Journal of Clinical Cases2021,9,22:7
9Atomic Fe-Zn dual-metal sites for high-efficiency pH-universal oxygen reduction catalysis显示文摘An effective electrocatalyst being highly active in all pH range for oxygen reduction reaction(ORR)is crucial for energy conversion and storage devices.However,most of the high-efficiency ORR catalysis was reported in alkaline conditions.Herein,we demonstrated the preparation of atomically dispersed Fe-Zn pairs anchored on porous N-doped carbon frameworks(Fe-Zn-SA/NC),which works efficiently as ORR catalyst in the whole pH range.It achieves high half-wave potentials of 0.78,0.85 and 0.72 V in 0.1 M HClO4,0.1 M KOH and 0.1 M phosphate buffer saline(PBS)solutions,respectively,as well as respectable stability.The performances are even comparable to Pt/C.Furthermore,when assembled into a Zn-air battery,the high power density of 167.2 mWcm−2 and 120 h durability reveal the feasibility of Fe-Zn-SA/NC in real energy-related devices.Theoretical calculations demonstrate that the superior catalytic activity of Fe-Zn-SA/NC can be contributed to the lower energy barriers of ORR at the Fe-Zn-N6 centers.This work demonstrates the potential of Fe-Zn pairs as alternatives to the Pt catalysts for efficient catalytic ORR and provides new insights of dual-atom catalysts for other energy conversion related catalytic reactions.Jie Xu Shuhua Lai Defeng Qi Min Hu Xianyun Peng Yifan Liu Wei Liu Guangzhi Hu Heng Xu Fan Li Chao Li Jia He Longchao Zhuo Jiaqiang Sun Yuan Qiu Shusheng Zhang Jun Luo Xijun Liu 2021Nano Research2021,14,5:6
10Dark matter direct search sensitivity of the PandaX-4T experiment显示文摘The Panda X-4T experiment, a 4-ton scale dark matter direct detection experiment, is being planned at the China Jinping Underground Laboratory. In this paper we present a simulation study of the expected background in this experiment. In a 2.8-ton fiducial mass and the signal region between 1-10 keV electron equivalent energy, the total electron recoil background is found to be 4.9 × 10^(-5) kg^(-1) d^(-1) keV^(-1). The nuclear recoil background in the same region is 2.8 × 10^(-7) kg^(-1) d^(-1) keV^(-1). With an exposure of 5.6 ton-years, the sensitivity of Panda X-4 T could reach a minimum spin-independent dark matter-nucleon cross section of 6 × 10^(-48) cm^2 at a dark matter mass of 40 Ge V/c^2.HongGuang Zhang Abdusalam Abdukerim Wei Chen Xun Chen YunHua Chen XiangYi Cui BinBin Dong DeQing Fang ChangBo Fu Karl Giboni Franco Giuliani LinHui Gu XuYuan Guo ZhiFan Guo Ke Han ChangDa He ShengMing He Di Huang XingTao Huang Zhou Huang Peng Ji XiangDong Ji YongLin Ju ShaoLi Li Yao Li Heng Lin HuaXuan Liu JiangLai Liu YuGang Ma YaJun Mao KaiXiang Ni JinHua Ning XiangXiang Ren Fang Shi AnDi Tan AnQing Wang Cheng Wang HongWei Wang Meng Wang QiuHong Wang SiGuang Wang XiuLi Wang XuMing Wang Zhou Wang MengMeng Wu ShiYong Wu JingKai Xia MengJiao Xiao PengWei Xie BinBin Yan JiJun Yang Yong Yang ChunXu Yu JuMin Yuan JianFeng Yue Dan Zhang Tao Zhang Li Zhao QiBin Zheng JiFang Zhou Ning Zhou XiaoPeng Zhou 2019Science China(Physics,Mechanics & Astronomy)2019,62,3:6
11Solute-homogenization model and its experimental verification in Mg-Gd-based alloys显示文摘Composition homogenization in solid solution is important for industrial alloys. In the present work, a solute homogenization model is proposed based on the chemical short-range-order tendency in Mg-Gdbased alloys. After a calculation using the cluster-plus-glue-atom model, the stable Mg-Gd structural unit is derived, [Gd-Mg12]Mg6, where one solute Gd is nearest-neighbored with twelve Mg atoms to form the characteristic hcp cluster [Gd-Mg12] and this cluster is matched with six Mg glue atoms. Such a local unit is then mixed with [Mg-Mg12]Mg3, the stable unit for pure Mg. Assuming that the Gd-containing units are arranged in fcc-or bcc-like lattice points and the Mg units in their octahedral interstices, three proportions between the two units are obtained, 1:1, 2:3, and 1:3, which constitute three solute homogenization modes. The prevailing Mg-Gd-based alloys are consequently classified into three groups, respectively exemplified by GW103 K(Mg-10 Gd-3 Y-0.4 Zr, wt%), GW83 K(Mg-8 Gd-3 Y-0.4 Zr), and GW63 K(Mg-6 Gd-3 Y-0.4 Zr). Mg-Gd-Y-Zr alloys were designed following the model(where Y and Zr were also added in substitution for Gd) and prepared by permanent-mould casting. According to their mechanical properties,the 1:3 alloy(Mg-5.9 Gd-1.6 Y-0.4 Zr) shows the best comprehensive properties(ultimate tensile strength305 MPa, yield strength 186 MPa, elongation 9.0%) in solution plus ageing state.Shengnan Qian Chuang Dong Tianyu Liu Ying Qin Qing Wang Yujuan Wu Lidong Gu Jianxin Zou Xiangwen Heng Liming Peng Xiaoqin Zeng 2018Journal of Materials Science & Technology2018,34,7:6
12Alterations of Alternative Splicing Patterns of Ser/Arg-Rich (SR) Genes in Response to Hormones and Stresses Treatments in Different Ecotypes of Rice (Oryza sativa)显示文摘Ser/Arg-rich (SR) genes encode proteins that play pivotal roles in both constitutive and alternative splicing of pre-mRNA. However, not much effort has been made to investigate the alternative splicing of their own pre-mRNA. In this study, we conducted comprehensive analyses of pre-mRNA splicing for 22 SR genes in three rice (Oryza sativa L.) ecotypes indica, japonica and javanica. Using different ecotypes we characterized the variations in expression and splicing patterns of rice SR genes in different tissues and at different developmental stages. In addition, we compared the divergence in expression and splicing patterns of SR genes from seedlings of different rice ecotypes in response to hormones application and environmental stresses. Our results revealed the complexity of alternative splicing of SR genes in rice. The splicing varies in different tissues, in different ecotypes, in response to stresses and hormones. Thus, our study suggested that SR genes were subjected to sophisticated alternative splicing although their encoding proteins were involved in the splicing process.ZHANG Peng DENG Heng XIAO Fang-ming LIU Yong-sheng 2013Journal of Integrative Agriculture2013,12,5:5
13Effect of applied pressure on microstructures of squeeze cast Mg-15Gd-1Zn-0.4Zr alloy显示文摘Microstructural evolution of Mg-15Gd-1Zn-0.4Zr(GZ151K,wt%)alloys,cast under 0 MPa(gravity cast)and 6 MPa(squeeze cast),were comparatively studied.It is found that the grain size of squeeze cast GZ151K alloy with applied stress 6 MPa is much smaller than that of the gravity cast counterpart.Moreover,the squeezing pressure hinders the transition fromβ’precipitates toβ1 precipitates during subsequent aging process,leading to reduced volume fraction ofβ1 precipitates in the squeeze cast alloy.Thus,the relatively lower volume fraction ofβ1 precipitates in the squeeze cast GZ151K results in higher hardness increment and stronger precipitation hardening effect.Qian Zhao Yujuan Wu Wei Rong Ke Wang Lingyang Yuan Xiangwen Heng Liming Peng 2018Journal of Magnesium and Alloys2018,6,2:5
14Chinese expert consensus on the management of chimeric antigen receptor T cell therapy-associated coagulopathy显示文摘Chimeric antigen receptor T-cell(CAR-T)therapy has greatly improved the disease remission rate and long-term survival rate of patients with relapsed/refractory hematological malignancies.[1-3]Currently,several commercial CAR-T products are available in the market and numerous CAR-T clinical trials have been conducted.Attention should be paid to the safety of CAR-T therapy.The main adverse effects of CAR-T therapy are cytokine release syndrome(CRS)and immune effector cell-associated neurotoxicity syndrome(ICANS).[4]Heng Mei Fangping Chen Yue Han Ming Hou He Huang Xiaojun Huang Yuhua Li Aibin Liang Qifa Liu Ting Niu Jun Peng Wenbin Qian Yongping Song Jianxiang Wang Ying Wang Depei Wu Kailin Xu Linhua Yang Renchi Yang Lei Zhang Liansheng Zhang Xi Zhang Xiaohui Zhang Weili Zhao Weidong Han Yu Hu 2022Chinese Medical Journal2022,,14:4
15Photoinduced large polaron transport and dynamics in organic-inorganic hybrid lead halide perovskite with terahertz probes显示文摘Organic-inorganic hybrid metal halide perovskites(MHPs)have attracted tremendous attention for optoelectronic applications.The long photocarrier lifetime and moderate carrier mobility have been proposed as results of the large polaron formation in MHPs.However,it is challenging to measure the effective mass and carrier scattering parameters of the photogenerated large polarons in the ultrafast carrier recombination dynamics.Here,we show,in a one-step spectroscopic method,that the optical-pump and terahertz-electromagnetic probe(OPTP)technique allows us to access the nature of interplay of photoexcited unbound charge carriers and optical phonons in polycrystalline CH_(3)NH_(3)PbI_(3)(MAPbI_(3))of about 10μm grain size.Firstly,we demonstrate a direct spectral evidence of the large polarons in polycrystalline MAPbI_(3).Using the Drude-Smith-Lorentz model along with the Frӧhlich-type electron-phonon(e-ph)coupling,we determine the effective mass and scattering parameters of photogenerated polaronic carriers.We discover that the resulting moderate polaronic carrier mobility is mainly influenced by the enhanced carrier scattering,rather than the polaron mass enhancement.While,the formation of large polarons in MAPbI_(3)polycrystalline grains results in a long charge carrier lifetime at room temperature.Our results provide crucial information about the photo-physics of MAPbI3 and are indispensable for optoelectronic device development with better performance.Zuanming Jin Yan Peng Yuqing Fang Zhijiang Ye Zhiyuan Fan Zhilin Liu Xichang Bao Heng Gao Wei Ren Jing Wu Guohong Ma Qianli Chen Chao Zhang Alexey VBalakin Alexander PShkurinov Yiming Zhu Songlin Zhuang 2022Light(Science & Applications)2022,11,8:4
16Variable Selection for Fixed Effects Varying Coefficient Models显示文摘We consider the problem of variable selection for the fixed effects varying coefficient models.A variable selection procedure is developed using basis function approximations and group nonconcave penalized functions, and the fixed effects are removed using the proper weight matrices. The proposed procedure simultaneously removes the fixed individual effects, selects the significant variables and estimates the nonzero coefficient functions. With appropriate selection of the tuning parameters, an asymptotic theory for the resulting estimates is established under suitable conditions. Simulation studies are carried out to assess the performance of our proposed method, and a real data set is analyzed for further illustration.Gao Rong LI Heng LIAN Peng LAI Heng PENG 2015Acta Mathematica Sinica,English Series2015,31,1:4
17The FAST Galactic Plane Pulsar Snapshot survey:I.Project design and pulsar discoveries显示文摘Discovery of pulsars is one of the main goals for large radio telescopes.The Five-hundredmeter Aperture Spherical radio Telescope(FAST),that incorporates an L-band 19-beam receiver with a system temperature of about 20 K,is the most sensitive radio telescope utilized for discovering pulsars.We designed the snapshot observation mode for a FAST key science project,the Galactic Plane Pulsar Snapshot(GPPS)survey,in which every four nearby pointings can observe a cover of a sky patch of 0.1575 square degrees through beam-switching of the L-band 19-beam receiver.The integration time for each pointing is 300 seconds so that the GPPS observations for a cover can be made in 21 minutes.The goal of the GPPS survey is to discover pulsars within the Galactic latitude of±10∘from the Galactic plane,and the highest priority is given to the inner Galaxy within±5∘.Up to now,the GPPS survey has discovered 201 pulsars,including currently the faintest pulsars which cannot be detected by other telescopes,pulsars with extremely high dispersion measures(DMs)which challenge the currently widely used models for the Galactic electron density distribution,pulsars coincident with supernova remnants,40 millisecond pulsars,16 binary pulsars,some nulling and mode-changing pulsars and rotating radio transients(RRATs).The follow-up observations for confirmation of new pulsars have polarization-signals recorded for polarization profiles of the pulsars.Re-detection of previously known pulsars in the survey data also leads to significant improvements in parameters for 64 pulsars.The GPPS survey discoveries are published and will be updated at http://gffzz656c80eee53645cchx0xu90xv0o0b6wnq.ffgz.tsg.suse.edu.cn/GPPS/.J.L.Han Chen Wang P.F.Wang Tao Wang D.J.Zhou Jing-Hai Sun Yi Yan Wei-Qi Su Wei-Cong Jing Xue Chen X.Y.Gao Li-Gang Hou Jun Xu K.J.Lee Na Wang Peng Jiang Ren-Xin Xu Jun Yan Heng-Qian Gan Xin Guan Wen-Jun Huang Jin-Chen Jiang Hui Li Yun-Peng Men Chun Sun Bo-Jun Wang H.G.Wang Shuang-Qiang Wang Jin-Tao Xie Heng Xu Rui Yao Xiao-Peng You D.J.Yu Jian-Ping Yuan Rai Yuen Chun-Feng Zhang Yan Zhu 2021Research in Astronomy and Astrophysics2021,21,5:4
18Clinical outcome of treating intractable hematospermia using holmium laser incision through a ureteroscope显示文摘Xiao-Jun Wu Heng Zhang Yong-Quan Wang Yi Zhi Ji Zheng Peng He Wei-Bing Li Zhan-Song Zhou 2016Asian Journal of Andrology2016,18,1:4
19Efficacy and safety of anlotinib plus S-1as thirdly-line or later-line treatmentin advanced non-small cell lung cancer显示文摘Objective Anlotinib,an oral vascular endothelial growth factor receptor 2(VEGFR2)inhibitor,has confirmed antitumor activity in lung cancer in both in vitro and in vivo assays,and has been recommended as third-line treatment agent in non-oncogene driven non-small cell lung cancer(NSCLC).This prospective study aimed to investigate the efficacy and safety of anlotinib plus S-1 for third-or later-line treatment in patients with advanced NSCLC.Methods Patients with histologically or cytologically confirmed NSCLC,and documented disease progression following second-line chemotherapy,and/or epidermal growth factor receptor-tyrosine kinase inhibitor(EGFR-TKI)treatment were enrolled in this study.The patients were treated anlotinib(8 mg daily d 1–14)and S-1(60 mg/m^2 d 1–14)and the treatment was repeated every 3 weeks.Treatment was continued until disease progression or unacceptable toxicity occurred.The objective response rate(ORR),disease control rate(DCR),progression-free survival(PFS),and adverse events(AEs)were reviewed and evaluated.Results Forty-one patients were enrolled in the study between June 2018 and December 2018.The total ORR and DCR were 26.8%and 80.5%,respectively.The median PFS was 5.2 months[95%confidence interval(CI),3.9 to 6.6 months].In the univariate analysis,there was a significant difference in the median PFS between patients with brain metastases and those without brain metastases(4.8 months vs 5.9 months,respectively;P=0.039).The Eastern Cooperative Oncology Group(ECOG)performance status(P=0.002),lines of therapy(P=0.015),and therapeutic evaluation(P=0.014)were independent factors that influenced PFS.The most common AEs were hypertension,proteinuria,myelosuppression,gastrointestinal reactions,fatigue,and mucositis.Conclusion Anlotinib plus S-1 is an effective and safe regimen for advanced NSCLC as third-or later-line therapy.Heng Cao Kai Liang Peng Liu Jing Wang Yuanyuan Ji Lujuan Xu Weilong Wu Shengnan Guo Xuekun Song Yonggui Hong 2020Oncology and Translational Medicine2020,6,1:4
20Searching for the Nano-Hertz Stochastic Gravitational Wave Background with the Chinese Pulsar Timing Array Data ReleaseⅠ显示文摘Observing and timing a group of millisecond pulsars with high rotational stability enables the direct detection of gravitational waves(GWs).The GW signals can be identified from the spatial correlations encoded in the times-of-arrival of widely spaced pulsar-pairs.The Chinese Pulsar Timing Array(CPTA)is a collaboration aiming at the direct GW detection with observations carried out using Chinese radio telescopes.This short article serves as a“table of contents”for a forthcoming series of papers related to the CPTA Data Release 1(CPTA DR1)which uses observations from the Five-hundred-meter Aperture Spherical radio Telescope.Here,after summarizing the time span and accuracy of CPTA DR1,we report the key results of our statistical inference finding a correlated signal with amplitude logA_(c)=-14.4_(-2.8)^(+1.0)for spectral index in the range ofα∈[-1.8,1.5]assuming a GW background(GWB)induced quadrupolar correlation.The search for the Hellings–Downs(HD)correlation curve is also presented,where some evidence for the HD correlation has been found that a 4.6σstatistical significance is achieved using the discrete frequency method around the frequency of 14 n Hz.We expect that the future International Pulsar Timing Array data analysis and the next CPTA data release will be more sensitive to the n Hz GWB,which could verify the current results.Heng Xu Siyuan Chen Yanjun Guo Jinchen Jiang Bojun Wang Jiangwei Xu Zihan Xue RNicolas Caballero Jianping Yuan Yonghua Xu Jingbo Wang Longfei Hao Jingtao Luo Kejia Lee Jinlin Han Peng Jiang Zhiqiang Shen Min Wang Na Wang Renxin Xu Xiangping Wu Richard Manchester Lei Qian Xin Guan Menglin Huang Chun Sun Yan Zhu 2023Research in Astronomy and Astrophysics2023,23,7:3
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