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Maize-soybean relay cropping increases soybean yield synergistically by extending the post-anthesis leaf stay-green period and accelerating grain filling
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作者 Yiling Li ping chen +7 位作者 Zhidan Fu Kai Luo ping Lin Chao Gao Shanshan Liu Tian Pu Taiwen Yong Wenyu Yang 《The Crop Journal》 SCIE CSCD 2023年第6期1921-1930,共10页
Relay cropping of Poaceae and Fabaceae promotes high yield and land-use efficiency by allowing a double harvest.However,it is difficult to increase yield synergistically because of the reduced photosynthetic abilities... Relay cropping of Poaceae and Fabaceae promotes high yield and land-use efficiency by allowing a double harvest.However,it is difficult to increase yield synergistically because of the reduced photosynthetic abilities of legume leaves under the shade of graminoids.Leaf photosynthetic capacity in relay cropping systems is associated with ecological niche differentiation and photosynthetic compensation after restoration of normal light.We conducted a field experiment in southwest China in 2020–2021 to evaluate the effects of three cropping patterns:maize–soybean relay cropping(IMS),monoculture maize(MM),and monoculture soybean(SS),and N application levels:no N application(NN:0 kg N ha^(−1)),reduced N(RN:180 kg N ha^(−1)),and conventional N(CN:240 kg N ha^(−1)).Compared to monocropping,relay cropping increased the stay-green traits of maize and soybean by 13%and 89%,respectively.Relay cropping prolonged the leaf stay-green duration in the maize and soybean lag phase by almost 4 and 8 days,respectively.Relay cropping maize(IM)increased the leaf area index(LAI)by 79.4%to 88.5%under NN and 55.5%to 148%under RN.Relay cropping soybean(IS)increased the LAI from 115%to 437%at days 40 to 50 after anthesis.IM increased yield by 65.6%.IS increased yield by 9.7%.HI and system yield were at their highest values under RN.In the relay cropping system,reduced N application extended green leaf duration,increased photosynthesis inside the canopy at multiple levels,ultimately increases soybean yield synergistically. 展开更多
关键词 Leaf stay-green Nitrogen reduction Maize-soybean relay cropping Yield
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Coordinated responses of leaf and nodule traits contribute to the accumulation of N in relay intercropped soybean
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作者 ping chen Qing Du +8 位作者 Benchuan Zheng Huan Yang Zhidan Fu Kai Luo ping Lin Yilin Li Tian Pu Taiwen Yong Wenyu Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1910-1928,共19页
Maize(Zea mays L.)-soybean(Glycine max L.Merr.)relay intercropping provides a way to enhance land productivity.However,the late-planted soybean suffers from shading by the maize.After maize harvest,how the recovery gr... Maize(Zea mays L.)-soybean(Glycine max L.Merr.)relay intercropping provides a way to enhance land productivity.However,the late-planted soybean suffers from shading by the maize.After maize harvest,how the recovery growth influences the leaf and nodule traits remains unclear.A three-year field experiment was conducted to evaluate the effects of genotypes,i.e.,supernodulating(nts1007),Nandou 12(ND12),and Guixia 3(GX3),and crop configurations,i.e.,the interspecific row spacing of 45(I45),60(I60),75 cm(I75),and sole soybean(SS),on soybean recovery growth and N fixation.The results showed that intercropping reduced the soybean total leaf area(LA)by reducing both the leaf number(LN)and unit leaflet area(LUA),and it reduced the nodule dry weight(NW)by reducing both the nodule number(NN)and nodule diameter(ND)compared with the SS.The correlation and principal component analysis(PCA)indicated a co-variability of the leaf and nodule traits in response to the genotype and crop configuration interactions.During the recovery growth stages,the compensatory growth promoted soybean growth to reduce the gaps of leaf and nodule traits between intercropping and SS.The relative growth rates of ureide(RGR_U)and nitrogen(RGR_N)accumulation were higher in intercropping than in SS.Intercropping achieved more significant sucrose and starch contents compared with SS.ND12 and GX3 showed more robust compensatory growth than nts1007 in intercropping.Although the recovery growth of relay intercropping soybean improved biomass and nitrogen accumulation,ND12 gained a more significant partial land equivalent ratio(pLER)than GX3.The I60 treatment achieved more robust compensation effects on biomass and N accumulation than the other configurations.Meanwhile,I60 showed a higher nodule sucrose content and greater shoot ureide and N accumulation than SS.Finally,intercropping ND12 with maize using an interspecific row spacing of 60 cm was optimal for both yield advantage and N accumulation. 展开更多
关键词 relay intercropping GENOTYPE crop configuration symbiotic nitrogen fixation SOYBEAN NODULE
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Tuning the electronic conductance of REH_(x)(RE=Nd,Ce,Pr)by structural deformation
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作者 Shangshang Wang Weijin Zhang +6 位作者 Jirong Cui Shukun Liu Hong Wen Jianping Guo Teng He Hujun Cao ping chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期440-445,I0010,共7页
Hydride ion(H-)conductors have drawn much attention due to their potential applications in hydrideion-based devices.Rare earth metal hydrides(REH_(x))have fast H-conduction which,unfortunately,is accompanied by detrim... Hydride ion(H-)conductors have drawn much attention due to their potential applications in hydrideion-based devices.Rare earth metal hydrides(REH_(x))have fast H-conduction which,unfortunately,is accompanied by detrimental electron conduction preventing their application as ion conductors.Here,REH_(x)(RE=Nd,Ce,and Pr)with varied grain sizes,rich grain boundaries,and defects have been prepared by ball milling and subsequent sintering.The electronic conductivity of the ball-milled REH_(x)samples can be reduced by 2-4 orders of magnitude compared with the non-ball-milled samples.The relationship of electron conduction and miscrostructures in REH_(x)is studied and discussed based on experimental data and previously-proposed classical and quantum theories.The H-conductivity of all REH_(x)is about 10^(-4)to 10^(-3)S cm^(-1)at room temperature,showing promise for the development of H-conductors and their applications in clean energy storage and conversion. 展开更多
关键词 Hydride ion conduction Electron conduction Nanosized grain Crystal defect Electron scattering
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Enhancing Green Ammonia Electrosynthesis Through Tuning Sn Vacancies in Sn‑Based MXene/ MAX Hybrids
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作者 Xinyu Dai Zhen‑Yi Du +10 位作者 Ying Sun ping chen Xiaoguang Duan Junjun Zhang Hui Li Yang Fu Baohua Jia Lei Zhang Wenhui Fang Jieshan Qiu Tianyi Ma 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期154-168,共15页
Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel S... Renewable energy driven N_(2) electroreduction with air as nitrogen source holds great promise for realizing scalable green ammonia production.However,relevant out-lab research is still in its infancy.Herein,a novel Sn-based MXene/MAX hybrid with abundant Sn vacancies,Sn@Ti_(2)CTX/Ti_(2)SnC–V,was synthesized by controlled etching Sn@Ti_(2)SnC MAX phase and demonstrated as an efficient electrocatalyst for electrocatalytic N2 reduction.Due to the synergistic effect of MXene/MAX heterostructure,the existence of Sn vacancies and the highly dispersed Sn active sites,the obtained Sn@Ti2CTX/Ti_(2)SnC–V exhibits an optimal NH_(3) yield of 28.4μg h^(−1) mg_(cat)^(−1) with an excellent FE of 15.57% at−0.4 V versus reversible hydrogen electrode in 0.1 M Na_(2)SO_(4),as well as an ultra-long durability.Noticeably,this catalyst represents a satisfactory NH3 yield rate of 10.53μg h^(−1) mg^(−1) in the home-made simulation device,where commercial electrochemical photovoltaic cell was employed as power source,air and ultrapure water as feed stock.The as-proposed strategy represents great potential toward ammonia production in terms of financial cost according to the systematic technical economic analysis.This work is of significance for large-scale green ammonia production. 展开更多
关键词 Green ammonia synthesis N2 electroreduction Renewable energy SN MXene/MAX hybrid
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Effect of grain size on gas bubble evolution in nuclear fuel:Phase-field investigations
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作者 孙丹 杨青峰 +7 位作者 赵家珺 高士鑫 辛勇 周毅 尹春雨 陈平 赵纪军 王园园 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期563-572,共10页
Numerous irradiation-induced gas bubbles are created in the nuclear fuel during irradiation, leading to the change of microstructure and the degradation of mechanical and thermal properties. The grain size of fuel is ... Numerous irradiation-induced gas bubbles are created in the nuclear fuel during irradiation, leading to the change of microstructure and the degradation of mechanical and thermal properties. The grain size of fuel is one of the important factors affecting bubble evolution. In current study, we first predict the thermodynamic behaviors of point defects as well as the interplay between vacancy and gas atom in both UO_(2) and U_(3)Si_(2) according to ab initio approach. Then, we establish the irradiation-induced bubble phase-field model to investigate the formation and evolution of intra-and inter-granular gas bubbles. The effects of fission rate and temperature on the evolutions of bubble morphologies in UO_(2) and U_(3)Si_(2) have been revealed. Especially, a comparison of porosities under different grain sizes is examined and analyzed. To understand the thermal conductivity as functions of grain size and porosity, the heat transfer capability of U_(3)Si_(2) is evaluated. 展开更多
关键词 grain size point defects fission gas bubble
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Comparative study of anti-inflammatory effects of different processed products through the COX-2/PGE2 signaling pathway: based on network pharmacology and molecular docking
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作者 ping chen Yun-Yun Quan +2 位作者 An-Qi Zeng Ying Dai Jin Zeng 《Pharmacology Discovery》 2024年第2期32-45,共14页
Background:Radix Aconiti Lateralis Preparata(Fu-zi)is a traditional Chinese medicinal herb,which has been widely used in the clinic and has potent anti-inflammatory activities.we aimed to explore the mechanisms of ext... Background:Radix Aconiti Lateralis Preparata(Fu-zi)is a traditional Chinese medicinal herb,which has been widely used in the clinic and has potent anti-inflammatory activities.we aimed to explore the mechanisms of extract containing alkaloids from different Fu-zi Processed Products(FPP)in treating inflammation,especially rheumatoid arthritis(RA).Methods:Firstly,using network pharmacology technology,the ingredients,and targets of Fu-zi were obtained by searching and screening,the targets involving RA were acquired,the intersection targets were constructed a"component-target-pathway"network.A comprehensive investigation was conducted on the anti-rheumatoid arthritis mechanisms of 5 FPPs in lipopolysaccharide(LPS)induced RAW264.7 cells,which serve as a model for RA.The production of NO and inflammatory cytokines were measured by ELISA kit.Quantitative Real-time PCR(qRT-PCR)was utilized to measure the mRNA levels.COX-2/PGE2 signaling pathway-associated proteins were determined by western blot.Results:According to a network pharmacological study,16 chemical components and 43 common targets were found in Fu-zi and 6 key targets including PTGS2 were closely related to the mechanism of Fu-zi in treating RA.The in vitro study revealed that the levels of NO,TNF-α,and IL-1βwere substantially decreased by the 5 FPPs.The 5 FPPs significantly suppressed the expression of proteins COX-2,iNOS,and NF-κB,with particularly notable effects observed for PFZ and XFZ.Conclusion:Altogether,these results demonstrated that the 5 PPS containing alkaloids have a good anti-RA-related inflammatory effect,and the mechanism may be related to COX-2/PGE2 signaling pathway,particularly,Fu-zi prepared utilizing a traditional Chinese technique. 展开更多
关键词 Radix Aconiti Lateralis Preparata(Fu-zi) rheumatoid arthritis ANTI-INFLAMMATORY network pharmacology COX-2/PGE2 signaling pathway
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Relay-intercropping soybean with maize maintains soil fertility and increases nitrogen recovery efficiency by reducing nitrogen input 被引量:11
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作者 Qing Du Li Zhou +11 位作者 ping chen Xiaoming Liu Chun Song Feng Yang Xiaochun Wang Weiguo Liu Xin Sun Junbo Du Jiang Liu Kai Shu Wenyu Yang Taiwen Yong 《The Crop Journal》 SCIE CAS CSCD 2020年第1期140-152,共13页
Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilizat... Optimized nitrogen(N)management can increase N-use efficiency in intercropping systems.Legume-nonlegume intercropping systems can reduce N input by exploiting biological N fixation by legumes.Measurement of N utilization can help in dissecting the mechanisms underlying N uptake and utilization in legume-nonlegume intercropping systems.An experiment was performed with three planting patterns:monoculture maize(MM),monoculture soybean(SS),and maize-soybean relay intercropping(IMS),and three N application levels:zero N(NN),reduced N(RN),and conventional N(CN)to investigate crop N uptake and utilization characteristics.N recovery efficiency and 15N recovery rate of crops were higher under RN than under CN,and those under RN were higher under intercropping than under the corresponding monocultures.Compared with MM,IMS showed a lower soil N-dependent rate(SNDR)in 2012.However,the SNDR of MM rapidly declined from 86.8%in 2012 to 49.4%in 2014,whereas that of IMS declined slowly from 75.4%in 2012 to 69.4%in 2014.The interspecific N competition rate(NCRms)was higher under RN than under CN,and increased yearly.Soybean nodule dry weight and nitrogenase activities were respectively 34.2%and 12.5%higher under intercropping than in monoculture at the beginning seed stage.The amount(Ndfa)and ratio(%Ndfa)of soybean N2 fixation were significantly greater under IS than under SS.In conclusion,N fertilizer was more efficiently used under RN than under CN;in particular,the relay intercropping system promoted N fertilizer utilization in comparison with the corresponding monocultures.An intercropping system helps to maintain soil fertility because interspecific N competition promotes biological N fixation by soybean by reducing N input.Thus,a maize-soybean relay intercropping system with reduced N application is sustainable and environmentally friendly. 展开更多
关键词 Maize-soybean relay intercropping Reduced nitrogen Biological nitrogen fixation Nitrogen recovery efficiency Soil nitrogen dependent rate
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利用多氟丙烯酸酯添加剂提升准二维钙钛矿发光二极管性能
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作者 张涛 龚思敏 +2 位作者 陈平 陈琪 陈立桅 《物理化学学报》 SCIE CAS CSCD 北大核心 2023年第12期87-94,共8页
准二维钙钛矿由于具有较大的激子结合能和高效的能量转移等优势,在发光二极管(light-emitting diodes,LED)中的应用前景被广泛看好。然而,准二维钙钛矿溶液加工成膜过程中易形成大量的低维相和表界面缺陷,引起严重的非辐射复合,成为限... 准二维钙钛矿由于具有较大的激子结合能和高效的能量转移等优势,在发光二极管(light-emitting diodes,LED)中的应用前景被广泛看好。然而,准二维钙钛矿溶液加工成膜过程中易形成大量的低维相和表界面缺陷,引起严重的非辐射复合,成为限制发光二极管器件性能的瓶颈。在本工作中,通过在PEA2Cs2Pb3Br10钙钛矿前驱体中加入1,6-二(丙烯酰氧基)-2,2,3,3,4,4,5,5-八氟己烷(OFHDODA)小分子添加剂,将钙钛矿薄膜的荧光量子效率(Photoluminescence Quantum Yield,PLQY)从19.7%提升到了49.0%,发射波长从508 nm红移到511 nm。这主要归因于OFHDODA与钙钛矿之间的物理化学相互作用有效抑制了非辐射复合,一方面多氟结构与PEA+之间的氢键相互作用调控了结晶动力学,抑制了低维相的产生;另一方面酯基具有较强的路易斯碱性,钝化了表界面未饱和Pb2+缺陷。相应地,准二维钙钛矿LED的外量子效率(External Quantum Efficiency,EQE)从8.55%提高到了13.76%。这项工作为设计新型多功能小分子添加剂,抑制准二维钙钛矿中的非辐射复合损失提供了思路。 展开更多
关键词 准二维钙钛矿 非辐射复合 低维相抑制 缺陷钝化 多氟丙烯酸酯添加剂
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Synthesis of Various Types of Silver Nanoparticles Used as Physical Developing Nuclei in Photographic Science
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作者 Jun ping ZHANG Li Qi SHENG ping chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第6期645-648,共4页
Ag nanoparticles used as physical developing nuclei in photographic science were prepared by reduction method. The as-formed Ag nanoparticle colloid was characterized by UV-Vis absorption spectrum, Atomic Force Micro... Ag nanoparticles used as physical developing nuclei in photographic science were prepared by reduction method. The as-formed Ag nanoparticle colloid was characterized by UV-Vis absorption spectrum, Atomic Force Microscopy(AFM) and Charge Coupled Device (CCD) technique. It is found that the source of Ag ions, the addition of surfactant and polymer, all have great influence on the size, topography and catalytic activity of Ag nanoparticles. 展开更多
关键词 Ag NANOPARTICLE AFM DTR.
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THE MONITORING FOR PHYSICAL DEVELOPING PROCESS WITH A LINEAR CCD
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作者 Jing Kun XU ping chen +1 位作者 Li ZHANG De Shui ZHENG(Institute of Photographic Chemistry, Academy of Sciences, Beijing. 100101) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第4期361-364,共4页
In this work, we used a linear CCD to detect the whole physical developing process of silver diffusion transfer reversal process in photographic chemistry. The influence of the ingredient of the working solution was s... In this work, we used a linear CCD to detect the whole physical developing process of silver diffusion transfer reversal process in photographic chemistry. The influence of the ingredient of the working solution was studied. 展开更多
关键词 THE MONITORING FOR PHYSICAL DEVELOPING PROCESS WITH A LINEAR CCD
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Transarterial Embolization Using Pingyangmycin-Lipiodol Emulsion (PLE) for Treatment of Focal Nodular Hyperplasia of the Liver and 1-Year Follow-Up: A Case Report and Literature Review
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作者 Junyao Qiu Song Wen +2 位作者 Laishu Luo ping chen Wuhua Guo 《Case Reports in Clinical Medicine》 2015年第1期1-5,共5页
Focal nodular hyperplasia (FNH) is a common benign hepatic tumor which is often treated non-operatively until it appears apparent symptoms such as pain and upper abdominal distension. We report here a case of trans-ca... Focal nodular hyperplasia (FNH) is a common benign hepatic tumor which is often treated non-operatively until it appears apparent symptoms such as pain and upper abdominal distension. We report here a case of trans-catheter arterial embolization (TAE) using pingyangmycin-lipiodol emulsion (PLE) for blocking a fatal bleeding originated from percutaneous biopsy as well as for FNH treatment. After embolization by means of the mixture of PLE and particles of gelfoam, the bleeding was stopped and the FNH was apparently shrinked 1 year later. TAE using PLE may be considered as a safe and effective method for the treatment of FNH. 展开更多
关键词 EMBOLIZATION Focal NODULAR HYPERPLASIA PINGYANGMYCIN
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Hydrogen energy carriers 被引量:1
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作者 Tom Autrey ping chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期119-121,I0004,共4页
The versatility of hydrogen will provide opportunities in large scale,long duration energy storage,and the decarbonization of industry.Hydrogen energy carriers are molecules and materials that store hydrogen at higher... The versatility of hydrogen will provide opportunities in large scale,long duration energy storage,and the decarbonization of industry.Hydrogen energy carriers are molecules and materials that store hydrogen at higher volumetric density than possible using gas phase hydrogen. 展开更多
关键词 HYDROGEN ENERGY HYDROGEN
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The inducible secreting TLR5 agonist,CBLB502,enhances the anti-tumor activity of CAR133-NK92 cells in colorectal cancer
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作者 Xiaohui Wang Wei Qiu +6 位作者 Haoyu Liu Min He Wei He Zhan Li Zhiqiang Wu Xiang Xu ping chen 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第9期662-681,共20页
Objective:CAR-T/NK cells have had limited success in the treatment of solid tumors,such as colorectal cancer(CRC),in part because of the heterogeneous nature of tumor-associated antigens that lead to antigen-negative ... Objective:CAR-T/NK cells have had limited success in the treatment of solid tumors,such as colorectal cancer(CRC),in part because of the heterogeneous nature of tumor-associated antigens that lead to antigen-negative relapse after the initial response.This barrier might be overcome by enhancing the recruitment and durability of endogenous immune cells.Methods:Immunohistochemistry and flow cytometry were used to assess the expression of CD133 antigen in tissue microarrays and cell lines,respectively.Retroviral vector transduction was used to generate CBLB502-secreting CAR133-NK92 cells(CAR133-i502-NK92).The tumor killing capacity of CAR133-NK92 cells in vitro and in vivo were quantified via LDH release,the RTCA assay,and the degranulation test,as well as measuring tumor bioluminescence signal intensity in mice xenografts.Results:We engineered CAR133-i502-NK92 cells and demonstrated that those cells displayed enhanced proliferation(9.0×10^(4)cells vs.7.0×10^(4)cells)and specific anti-tumor activities in vitro and in a xenogeneic mouse model,and were well-tolerated.Notably,CBLB502 secreted by CAR133-i502-NK92 cells effectively activated endogenous immune cells.Furthermore,in hCD133+/hCD133−mixed cancer xenograft models,CAR133-i502-NK92 cells suppressed cancer growth better than the counterparts(n=5,P=0.0297).Greater T-cell infiltration was associated with greater anti-tumor potency(P<0.0001).Conclusions:Armed with a CBLB502 TLR5 agonist,CAR133-NK92 cells were shown to be capable of specifically eliminating CD133-positive colon cancer cells in a CAR133-dependent manner and indirectly eradicating CD133-negative colon cancer cells in a CBLB502-specific endogenous immune response manner.This study describes a novel technique for optimizing CAR-T/NK cells for the treatment of antigenically-diverse solid tumors. 展开更多
关键词 TLR5 agonist CBLB502 CAR133 endogenous immune response colorectal cancer
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Developments and challenges in neoadjuvant therapy for locally advanced pancreatic cancer
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作者 Bo Zhou Shi-Ran Zhang +1 位作者 Geng chen ping chen 《World Journal of Gastroenterology》 SCIE CAS 2023年第35期5094-5103,共10页
Pancreatic ductal adenocarcinoma(PDAC)remains a significant public health challenge and is currently the fourth leading cause of cancer-related mortality in developed countries.Despite advances in cancer treatment,the... Pancreatic ductal adenocarcinoma(PDAC)remains a significant public health challenge and is currently the fourth leading cause of cancer-related mortality in developed countries.Despite advances in cancer treatment,the 5-year survival rate for patients with PDAC remains less than 5%.In recent years,neoadjuvant therapy(NAT)has emerged as a promising treatment option for many cancer types,including locally advanced PDAC,with the potential to improve patient outcomes.To analyze the role of NAT in the setting of locally advanced PDAC over the past decade,a systematic literature search was conducted using PubMed and Web of Science.The results suggest that NAT may reduce the local mass size,promote tumor downstaging,and increase the likelihood of resection.These findings are supported by the latest evidence-based medical literature and the clinical experience of our center.Despite the potential benefits of NAT,there are still challenges that need to be addressed.One such challenge is the lack of consensus on the optimal timing and duration of NAT.Improved criteria for patient selection are needed to further identify PDAC patients likely to respond to NAT.In conclusion,NAT has emerged as a promising treatment option for locally advanced PDAC.However,further research is needed to optimize its use and to better understand the role of NAT in the management of this challenging disease.With continued advances in cancer treatment,there is hope of improving the outcomes of patients with PDAC in the future. 展开更多
关键词 Neoadjuvant therapy Pancreatic ductal adenocarcinoma Locally advanced pancreatic cancer CHEMORADIOTHERAPY IMMUNOTHERAPY Vaccine therapy
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NaH doped TiO_(2)as a high-performance catalyst for Mg/MgH_(2)cycling stability and room temperature absorption
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作者 Joshua Adedeji Bolarin Zhao Zhang +3 位作者 Hujun Cao Zhi Li Teng He ping chen 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第8期2740-2749,共10页
This paper presents the catalytic effect of NaH doped nanocrystalline TiO_(2)(designated as NaTiOxH)in the improvement of MgH_(2)hydrogen storage properties.The catalyst preparation involves ball milling NaH with TiO_... This paper presents the catalytic effect of NaH doped nanocrystalline TiO_(2)(designated as NaTiOxH)in the improvement of MgH_(2)hydrogen storage properties.The catalyst preparation involves ball milling NaH with TiO_(2)for 3 hr.The addition of 5 wt%NaTiOxH powder into MgH_(2)reduces its operating temperature to∼185℃,which is∼110℃lower than the additive-free as-milled MgH_(2).The composite remarkably desorbs∼7.2 wt%H_(2)within 15 min at∼290℃and reabsorbs∼4.5 wt%H_(2)in 45 min at room temperature under 50 bar H_(2).MgH_(2)dehydrogenation is activated at 57 kJ/mol by the catalyst.More importantly,the addition of 2.5 wt%NaTiOxH catalyst aids MgH_(2)to reversibly produce∼6.1 wt%H_(2)upon 100 cycles within 475 hr at 300℃.Microstructural investigation into the catalyzed MgH_(2)composite reveals a firm contact existing between NaTiOxH and MgH_(2)particles.Meanwhile,the NaTiOxH catalyst consists of catalytically active Ti_(3)O_(5),and“rod-like”Na_(2)Ti_(3)O_(7)species liberated in-situ during preparation;these active species could provide multiple hydrogen diffusion pathways for an improved MgH_(2)sorption process.Furthermore,the elemental characterization identifies the reduced valence states of titanium(Ti<4+)which show some sort of reversibility consistent with H_(2)insertion and removal.This phenomenon is believed to enhance the mobility of Mg/MgH_(2)electrons by the creation and elimination of oxygen vacancies in the defective(TiO_(2-x))catalyst.Our findings have therefore moved MgH_(2)closer to practical applications. 展开更多
关键词 Magnesium hydride NaH doped nanocrystalline TiO_(2) Kinetics Room temperature absorption REVERSIBILITY
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Influence of the lattice parameter of the AlN buffer layer on the stress state of GaN film grown on(111)Si
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作者 张臻琢 杨静 +3 位作者 赵德刚 梁锋 陈平 刘宗顺 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期493-498,共6页
GaN films grown on(111)Si substrate with different lattice parameters of the AlN buffer layer by metal–organic chemical vapor deposition are studied.The stress states obtained by different test methods are compared a... GaN films grown on(111)Si substrate with different lattice parameters of the AlN buffer layer by metal–organic chemical vapor deposition are studied.The stress states obtained by different test methods are compared and it is found that the lattice parameter of the AlN buffer layer may have a significant effect on the stress state in the initial stage of subsequent GaN film growth.A larger compressive stress is beneficial to improved surface morphology and crystal quality of GaN film.The results of further orthogonal experiments show that an important factor affecting the lattice parameter is the growth rate of the AlN buffer layer.This work may be helpful for realizing simple GaN-on-Si structures and thus reducing the costs of growth processes. 展开更多
关键词 GAN Si substrate AlN buffer layer stress control
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Influence of Bayer Red Mud on the Operational and Mechanical Characteristics of Composite Cement Mortar
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作者 cheng Hu Weiheng Xiang +6 位作者 ping chen Yi Yang Libo Zhou Jiufang Jiang Shunkai Li Yang Ming Qing Li 《Journal of Renewable Materials》 EI 2023年第11期3945-3956,共12页
The aim of this study is to enhance the value and utilization of red mud generated in the Bayer process by preparing composite cement mortars.The effects of two different types of Bayer red mud with varying physical a... The aim of this study is to enhance the value and utilization of red mud generated in the Bayer process by preparing composite cement mortars.The effects of two different types of Bayer red mud with varying physical and chemical characteristics on the fluidity,mechanical strength,mineral composition,and microstructure of the composite cement mortar were systematically evaluated.The results showed that the optimal addition of red mud A was 10 wt%,while it was 20 wt% for red mud B.The mechanical properties of the composite cement mortar met the standards for P·O42.5 cement.Furthermore,the composite mortar with the addition of red mud B showed higher flexural and compressive strengths compared to the composite mortar with red mud A.This improvement is attributed to the smaller particle size of red mud B,which filled the micro-pores and increased the compactness of the cement stone,as well as its higher content of Na_(2)O,K_(2)O,and other free alkalis,which resulted in more obvious alkali activation,accelerating the hydration of the active minerals in the slurry. 展开更多
关键词 Bayer red mud composite cement mortar FLUIDITY mechanical strength MICROSTRUCTURE
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Export of Greenland Sea water across the Mohn Ridge induced by summer storms
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作者 Xusiyang Shen Jinping Zhao +4 位作者 Xiaoyu Wang Tore Hattermann Wenqi Shi Long Lin ping chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期17-28,共12页
The Mohn Ridge separates the Greenland Sea and the Lofoten Basin.Previous studies identified the export across the Mohn Ridge(EMR)from the Greenland Basin into the Lofoten Basin using water mass analysis and the trace... The Mohn Ridge separates the Greenland Sea and the Lofoten Basin.Previous studies identified the export across the Mohn Ridge(EMR)from the Greenland Basin into the Lofoten Basin using water mass analysis and the tracer diffusion method,but there is still lack of direct current measurements.A surface mooring with four current meters was deployed on the Mohn Ridge from June 5 to June 18 in 2015,when three cyclones passed in the adjacent area.In the absence of cyclones,the flow on the Mohn Ridge was northeastward,parallel to the ridge.When cyclones appeared,the EMR occurred to transport Greenland Sea water into the Lofoten Basin.The probable mechanism is the sea level height variation caused by the perturbation of the low pressure of cyclones,which yields an outward pressure gradient force to drive the outflow.Our results suggest that the outflow is intermittent and only happens during cyclone activities.The annual mean volume flux of EMR was roughly estimated by the limited data,which is about 3.8×10^(6)m^(3)/s,a little bit smaller than the estimation based on volume conservation.The results indicate that the contribution of the cyclonic storms to EMR is a greatly important mechanism that potentially influences the global thermohaline circulation through the Greenland-Scotland Ridge overflow. 展开更多
关键词 Mohn Ridge current measurement CYCLONE
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Atlas of dynamic spectra of fast radio burst FRB 20201124A
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作者 王铂钧 胥恒 +64 位作者 姜金辰 徐江伟 牛佳瑞 陈平 李柯伽 张冰 朱炜玮 东苏勃 张春风 傅海 周德江 张永坤 王培 冯毅 李晔 李冬子 鲁文宾 杨元培 RNCaballero 蔡策 陈卯蒸 戴子高 艾力·伊沙木丁 甘恒谦 韩金林 郝龙飞 黄玉祥 姜鹏 李承奎 李菂 李辉 李新乔 李志玄 刘志勇 罗睿 门云鹏 牛晨辉 彭文溪 钱磊 宋黎明 孙京海 王发印 汪敏 王娜 王维扬 吴雪峰 肖硕 熊少林 徐永华 徐仁新 杨俊 杨轩 姚蕊 易祁彬 岳友岭 于东俊 余文飞 袁建平 张彬彬 张松波 张双南 赵一 郑伟康 朱岩 邹金航 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第2期1-4,共4页
Fast radio bursts(FRBs) are highly dispersed millisecond-duration radio bursts,[1,2]of which the physical origin is still not fully understood. FRB 20201124A is one of the most actively repeating FRBs. In this paper, ... Fast radio bursts(FRBs) are highly dispersed millisecond-duration radio bursts,[1,2]of which the physical origin is still not fully understood. FRB 20201124A is one of the most actively repeating FRBs. In this paper, we present the collection of 1863 burst dynamic spectra of FRB 20201124A measured with the Five-hundred-meter Aperture Spherical radio Telescope(FAST). The current collection, taken from the observation during the FRB active phase from April to June 2021, is the largest burst sample detected for any FRB so far. The standard PSRFITs format is adopted, including dynamic spectra of the burst, and the time information of the dynamic spectra, in addition, mask files help readers to identify the pulse positions are also provided. The dataset is available in Science Data Bank, with the link https://www.doi.org/10.57760/sciencedb.j00113.00076. 展开更多
关键词 fast radio burst FAST
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慢性胃炎镜下病理特点与幽门螺杆菌血清抗体类型的相关性研究 被引量:25
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作者 陈萍 李军民 +1 位作者 吕祥瑞 王慧 《中国内镜杂志》 2018年第8期81-85,共5页
目的探讨不同菌型幽门螺杆菌(Hp)血清抗体类型与慢性胃炎发生率及其病理特点的关系。方法选取该院2014年11月-2016年11月收治疗的上腹部不适的患者650例作为研究对象,所有患者均行胃镜检查,所有患者均行Hp呼气实验检查Hp,并采用酶联免... 目的探讨不同菌型幽门螺杆菌(Hp)血清抗体类型与慢性胃炎发生率及其病理特点的关系。方法选取该院2014年11月-2016年11月收治疗的上腹部不适的患者650例作为研究对象,所有患者均行胃镜检查,所有患者均行Hp呼气实验检查Hp,并采用酶联免疫吸附法检查患者血清中Hp抗体类型,采用Logistic分析Hp感染与慢性胃炎发生及其病理特点的关系。结果 650例患者中慢性胃炎93例,以Hp(-)为对照组,Hp(+)组患者慢性胃炎风险是Hp(-)患者的1.6倍,Hp(+)Cag A-Ig G+患者慢性胃炎是Hp(-)患者的2.3倍,Hp(+)Cag A-Ig G-患者慢性胃炎是Hp(-)患者的1.8倍。慢性萎缩性胃炎(CAG)患者27例中,以Hp(-)为参照,Hp(+)组患者CAG是Hp(-)患者的2.1倍,Hp(+)Cag A-Ig G-患者CAG是Hp(-)患者的1.9倍,Hp(+)Cag A-Ig G+患者CAG是Hp(-)患者的2.9倍;CAG伴不典型增生(Dys)患者13例中,以Hp(-)为参照,Hp(+)组患者是Hp(-)患者的2.4倍,Hp(+)Cag A-Ig GCAG伴Dys是Hp(-)患者的3.5倍,Cag A-Ig G+的慢性胃炎患者炎症反应程度明显比Hp(-)及Cag A-Ig G-的患者高,且炎症活动度明显更高。结论 Hp(+)Cag A-Ig G+感染加重慢性胃炎患者胃黏膜患者的炎症反应,同时促进慢性胃炎向CAG伴Dys发展。 展开更多
关键词 CagA-IgG+ 幽门螺杆菌感染 胃炎 病理表现
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