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Degradation of warm permafrost and talik formation on the Qinghai-Tibet Plateau in 2006-2021

Advances in Climate Change Research 2024年第2期15卷 275-284页

作者： Qi-Hang MEI Ji CHEN You-Qian LIU Shou-Hong ZHANG Jing-Yi ZHAO Tian-Chun DONG jun-cheng wang Yao-jun ZHAO Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment Key Laboratory of Cryospheric Science and Frozen Soil EngineeringNorthwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co.Ltd Xining 810007China University of Chinese Academy of Sciences Beijing 100049China

Permafrost is degrading globally,particularly those with low thermal stability on the Qinghai-Tibet Plateau,owing to climate change.However,the inadequacy of direct research on permafrost degradation based on in-situ monitoring limits the prediction of permafrost degradation and engineering practices.This study explored the processes and modes of permafrost degradation into talik by analyzing ground temperature data from five points in the hinterland of the Qinghai-Tibet Plateau from 2006 to 2021.The results showed that the degradation of the warm permafrost layer with a geothermal gradient of zero occurred simultaneously in the top and bottom directions.The rate of permafrost degradation from the top down and bottom up increase during the degradation process,but the increase of the former is more drastic after the formation of thawed interlayer.Additionally,the construction of the Qinghai-Tibet Railway changed the degradation modes of the permafrost in adjacent natural sites through horizontal heat transfer,particularly after through talik formation under the embankment.The findings suggest that taking countermeasures before or immediately after forming thawed interlayer is more effective.When evaluating the thermal impact of projects in warm permafrost regions,special attention should be given to the horizontal heat transfer process that may result from the formation of a through talik.

关键词： Warm permafrost Degradation Talik Qinghai-Tibet Plateau Climate change

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A case of clonal seborrheic keratosis with characteristic dermoscopic features

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Chinese Medical Journal 2020年第4期133卷 499-500页

作者： jun-cheng wang Jie Liu Department of Dermatology Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China

To the Editor:A 40-year-old woman presented with a gradually enlarging red oval plaque with a rough surface on the lateral aspect of the left leg for 4 years.No ulceration,crust,exudation,or bleeding was seen.Physical examination showed the lesion was a well-defined,red flat plaque,1.5 cm×1.0 cm in diameter,medium hardness,and non-tender[Figure 1A].There were no systematic abnormalities and the patient had no complaints of pain or itching.Dermoscopic examination revealed multiple brown globules,dotted,and globular vessels on the red background.Several follicular keratotic plugs and multiple milia-like cysts could also be seen.The lesion had a demarcated border[Figure 1B and Figure 1C].

关键词： Figure characteristic kerato

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A nomogram predicting the recurrence of hepatocellular carcinoma in patients after laparoscopic hepatectomy

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Cancer Communications 2019年第1期39卷 499-509页

作者： Yang-Xun Pan Jian-Cong Chen Ai-Ping Fang Xiao-Hui wang Jin-Bin Chen jun-cheng wang Wei He Yi-Zhen Fu Li Xu Min-Shan Chen Yao-jun Zhang Qi-Jiong Li Zhong-Guo Zhou State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineSun Yat-sen University Cancer CenterGuangzhou 510060GuangdongP.R.China Department of Liver Surgery Sun Yat-sen University Cancer Center651 Dongfeng Road EastGuangzhou 510060GuangdongP.R.China Department of Public Health Sun Yat-sen UniversityGuangzhou 510080GuangdongP.R.China Department of Molecular Medicine California Campus The Scripps Research Institute10550North Torrey Pines RoadLa JollaCA 92037USA

Background:Patients with hepatocellular carcinoma(HCC)undergoing surgical resection still have a high 5-year recurrence rate(~60%).With the development of laparoscopic hepatectomy(LH),few studies have compared the efficacy between LH and traditional surgical approach on HCC.The objective of this study was to establish a nomo-gram to evaluate the risk of recurrence in HCC patients who underwent LH.Methods:The clinical data of 432 patients,pathologically diagnosed with HCC,underwent LH as initial treatment and had surgical margin>1 cm were collected.The significance of their clinicopathological features to recurrence-free survival(RFS)was assessed,based on which a nomogram was constructed using a training cohort(n=324)and was internally validated using a temporal validation cohort(n=108).Results:Hepatitis B surface antigen(hazard ratio[HR],1.838;P=0.044),tumor number(HR,1.774;P=0.003),tumor thrombus(HR,2.356;P=0.003),cancer cell differentiation(HR,0.745;P=0.080),and microvascular tumor invasion(HR,1.673;P=0.007)were found to be independent risk factors for RFS in the training cohort,and were used for con-structing the nomogram.The C-index for RFS prediction in the training cohort using the nomogram was 0.786,which was higher than that of the 8th edition of the American Joint Committee on Cancer TNM classification(C-index,0.698)and the Barcelona Clinic Liver Cancer staging system(C-index,0.632).A high consistency between the nomogram prediction and actual observation was also demonstrated by a calibration curve.An improved predictive benefit in RFS and higher threshold probability of the nomogram were determined by receiver operating characteristic curve analysis,which was also confirmed in the validation cohort compared to other systems.Conclusions:We constructed and validated a nomogram able to quantify the risk of recurrence after initial LH for HCC patients,which can be clinically implemented in assisting the planification of individual postoperative surveil-lance protocols.

关键词： Hepatocellular carcinoma Laparoscopic hepatectomy Recurrence Nomogram American Joint Committee on Cancer TNM classification Barcelona Clinic Liver Cancer staging system Hepatitis B surface antigen Tumor thrombus Tumor invasion

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HMGB1基因调控胶质瘤恶性生物学行为研究进展

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中国现代神经疾病杂志 2024年第5期24卷 391-397页

作者：王军成赵岳阳杨强蒯涛潘亚文兰州大学第二临床医学院 730030 宁夏回族自治区人民医院肿瘤科银川750001 兰州大学第二医院神经外科 730030 宁夏回族自治区人民医院神经外科银川750001 兰州大学神经病学研究所 730030

胶质瘤因其复杂的生物学特性以及胶质瘤干细胞的干细胞特性,标准治疗后易复发。高迁移率族蛋白1(HMGB1)作为癌基因通过多种不同方式参与调控胶质瘤恶性进展。本文对HMGB1基因与胶质瘤预后、肿瘤病理分级、干细胞相关性以及HMGB1基因调... 详细信息

胶质瘤因其复杂的生物学特性以及胶质瘤干细胞的干细胞特性,标准治疗后易复发。高迁移率族蛋白1(HMGB1)作为癌基因通过多种不同方式参与调控胶质瘤恶性进展。本文对HMGB1基因与胶质瘤预后、肿瘤病理分级、干细胞相关性以及HMGB1基因调控胶质瘤方式如非编码RNA途径、细胞自噬途径、肿瘤微环境等进行综述,为胶质瘤的治疗提供参考。

关键词：神经胶质瘤 HMGB1蛋白质 RNA 未翻译自噬肿瘤微环境综述

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Manipulating Crystal Growth and Secondary Phase PbI_(2)to Enable Efficient and Stable Perovskite Solar Cells with Natural Additives

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Nano-Micro Letters 2024年第9期16卷 432-448页

作者： Yirong wang Yaohui cheng Chunchun Yin Jinming Zhang Jingxuan You Jizheng wang Jinfeng wang jun Zhang Institute of Chemistry Chinese Academy of Sciences(CAS)Beijing 100190People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Nanjing University Nanjing 210023People’s Republic of China Wuhan Textile University Wuhan 430200People’s Republic of China

In perovskite solar cells(PSCs),the inherent defects of perovskite film and the random distribution of excess lead iodide(PbI_(2))prevent the improvement of efficiency and stability.Herein,natural cellulose is used as the raw material to design a series of cellulose derivatives for perovskite crystallization engineering.The cationic cellulose derivative C-Im-CN with cyano-imidazolium(Im-CN)cation and chloride anion prominently promotes the crystallization process,grain growth,and directional orientation of perovskite.Meanwhile,excess PbI_(2)is transferred to the surface of perovskite grains or formed plate-like crystallites in local domains.These effects result in suppressing defect formation,decreasing grain boundaries,enhancing carrier extraction,inhibiting non-radiative recombination,and dramatically prolonging carrier lifetimes.Thus,the PSCs exhibit a high power conversion efficiency of 24.71%.Moreover,C-Im-CN has multiple interaction sites and polymer skeleton,so the unencapsulated PSCs maintain above 91.3%of their initial efficiencies after 3000 h of continuous operation in a conventional air atmosphere and have good stability under high humidity conditions.The utilization of biopolymers with excellent structure-designability to manage the perovskite opens a state-of-the-art avenue for manufacturing and improving PSCs.

关键词： Perovskite Solar cells Defect passivation Biomass additives Crystal orientation

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Two-way shape memory effect in a Ti-Zr-Nb-Ta high-temperature shape memory alloy

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Rare Metals 2024年第3期43卷 1257-1262页

作者： cheng-Yang Xiong Tuo Li jun wang Yan Li School of Materials Science and Engineering Beihang UniversityBeijing100191China

The two-way shape memory effect in a Ti-18.5Zr-10Nb-3.5Ta high-temperature shape memory alloy was investigated.X-ray diffraction measurem ent shows that the alloy is composed of orthorhombicα"-martensite.ωphase is not found in Ti-18.5Zr-10Nb-3.5Ta alloy due to the suppressing effect of Ta element.Theα"-martensite laths are found in the transmission electron microscope observation;after the bending deformation,there appear a lot of dislocations.The alloy exhibits a shape memory strain of 3.8%aud a high reverse martensite transformation start temperature of 464 K.The maximum two-way shape memory strain of 1.2%is obtained in the alloy with the prebending training strain of 10%.The mechanism can be ascribed to the effect of internal stress field caused by dislocations.

关键词： Ti-Zr Shape memory alloys Two-way shape memory effect

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Macroscopic model and statistical model to characterize electromagnetic information of a digital coding metasurface

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National Science Review 2024年第3期11卷 159-171页

作者： Rui Wen Shao jun Wei Wu Zheng Xing wang Hui Xu Han Qing Yang Qiang cheng Tie jun Cui Institute of Electromagnetic Space Southeast University State Key Laboratory of Millimeter Waves Southeast University Peng cheng Laboratory Pazhou Laboratory(Huangpu)

A digital coding metasurface is a platform connecting the digital space and electromagnetic wave space, and has therefore gained much attention due to its intriguing value in reshaping wireless channels and realizing new communication architectures. Correspondingly, there is an urgent need for electromagnetic information theory that reveals the upper limit of communication capacity and supports the accurate design of metasurface-based communication systems. To this end, we propose a macroscopic model and a statistical model of the digital coding metasurface. The macroscopic model uniformly accommodates both digital and electromagnetic aspects of the meta-atoms and predicts all possible scattered fields of the digital coding metasurface based on a small number of simulations or measurements. Full-wave simulations and experimental results show that the macroscopic model is feasible and accurate. A statistical model is further proposed to correlate the mutual coupling between meta-atoms with covariance and to calculate the entropy of the equivalent currents of digital coding metasurface. These two models can help reconfigurable intelligent surfaces achieve more accurate beamforming and channel estimation, and thus improve signal power and coverage. Moreover, the models will encourage the creation of a precoding codebook in metasurface-based direct digital modulation systems, with the aim of approaching the upper limit of channel capacity. With these two models, the concepts of current space and current entropy, as well as the analysis of information loss from the coding space to wave space, is established for the first time, helping to bridge the gap between the digital world and the physical world, and advancing developments of electromagnetic information theory and new-architecture wireless systems.

关键词： electromagnetic information theory current entropy current space digital coding metasurface macroscopic model statistical model

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体重过重和化疗栓塞初始治疗期间体重显著下降对肝癌患者总体生存的影响

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Gastroenterology Report 2020年第2期8卷 125-133,I0002页

作者： Zhen-Xin Chen Zhi-Wei Jian Xi-Wen Wu jun-cheng wang Jing-Yuan Peng Chun-Yu Huang Xiang-Ming Lao Department of Hepatobiliary and Pancreatic Surgery Sun Yat-sen University Cancer CenterState Key Laboratory of Southern ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdongP.R.China Department of Endoscopy Sun Yat-sen University Cancer CenterState Key Laboratory of Southern ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdongP.R.China

背景:体重过重和体重下降对于肝癌进展和预后的影响尚不明了。本研究旨在评估体重过重和化疗栓塞初始治疗期间体重下降对中晚期肝癌患者生存的影响。方法:2009年12月至2015年5月间,1170例在中山大学附属肿瘤医院接受化疗栓塞初始治疗的... 详细信息

背景:体重过重和体重下降对于肝癌进展和预后的影响尚不明了。本研究旨在评估体重过重和化疗栓塞初始治疗期间体重下降对中晚期肝癌患者生存的影响。方法:2009年12月至2015年5月间,1170例在中山大学附属肿瘤医院接受化疗栓塞初始治疗的B/C期(巴塞罗那肝癌分期)肝癌患者纳入分析。基线体质指数≥23 kg/m^(2)定义为体重过重,化疗栓塞初始治疗期间体重下降≥5.0%定义为体重显著下降。采用Cox回归分析评估体重过重和体重显著下降对总体生存(OS)的影响。结果:体重过重组和非体重过重组患者中位生存时间分别为16.8(95%CI:13.9–19.7)个月和11.1(95%CI:10.0–12.2)个月(P<0.001)。Cox多因素分析证实,体重过重是OS的独立保护因素(P<0.001)。亚组分析显示,在初始化疗栓塞后接受了进一步后续治疗的患者中,体重过重对OA存在显著影响(P=0.005);但在没有接受后续治疗的患者,体重过重并不会影响OA(P=0.683)。多因素分析显示,在接受了后续治疗的肝癌患者中,体重过重和体重显著下降均为OS的独立影响因素。结论:在接受化疗栓塞初始治疗的中晚期肝癌患者中,体重过重者会有一个更长的OS;而初始治疗期间体重显著下降则是OS的一个独立危险因素。

关键词： overweightness critical weight loss hepatocellular carcinoma chemoembolization overall survival

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Mitigating set-stuck failure in 3D phase change memory: substituting square pulses with surge pulses

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Science China(Information Sciences) 2024年第5期67卷 295-301页

作者： Ninghua LI wang CAI jun XIANG Hao TONG Weiming cheng Xiangshui MIAO School of Integrated Circuits Huazhong University of Science and Technology Hubei Yangtze Memory Laboratories Hubei Institute of Measurement and Testing Technology

In the devices that integrate phase change memory(PCM) and ovonic threshold switching(OTS),the OTS threshold voltage often surpasses the RESET operation voltage of PCM. The conventional application of square pulses hinders the successful completion of the SET operation in these integrated devices. To address this challenge, a novel pulse called the surge pulse is introduced, which comprises a high amplitude pulse for OTS activation and a low amplitude pulse for PCM operation. By employing COMSOL simulation,the operational effectiveness of both square pulses and surge pulses is validated. Test results reveal that using a square pulse to operate the integrated device accelerates the occurrence of SET-stuck failure(SSF).In contrast, the surge pulse enables the integrated device to operate for at least 1000 cycles while preserving the essential cyclic characteristics. Additionally, an investigation into the overshoot component of the surge pulse is conducted, revealing that an increase in overshoot amplitude and pulse width also accelerates the emergence of SSF. By applying the theory of ion migration induced by the electric field, the root cause of SSF in integrated devices is explained, and the accuracy of the theory is validated through the application of a reverse pulse. In summary, this study elucidates the rationality of replacing the square pulse with a surge pulse, presenting a superior approach for operating PCM and OTS integrated devices.

关键词： surge pulse phase change memory (PCM) integration SET-stuck failure (SSF) square pulse

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Effect of Ga on the microstructure and properties of NiCoV alloy at different annealing temperatures

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Progress in Natural Science:Materials International 2024年第2期34卷 408-419页

作者： Jin Li Peng wang Lvxing Chen Meifeng He jun cheng School of Materials and Chemistry University of Shanghai for Science and Technology Northwest Institute for Nonferrous Metal Research Shaanxi Key Laboratory of Biomedical Metal Materials

To obtain a high-entropy alloy characterized by high strength and plasticity,（NiCoV）100-xGaxx=0,5,7) was successfully prepared,cold-rolled,and heat-treated.The microstructure was analyzed to correlate Ga content with the performance of the system.The addition of Ga can produce alloying effects,including solid solution strengthening effect,second phase precipitation strengthening effect,and layer misalignment energy reduction effect.The experimental results show adding Ga elements can enrich Ni,Co,V,and Ga above the grain boundaries,causing the alloy to produce annealed twins inside.The alloy is strengthened mainly by precipitation,and the formation of the precipitation phase effectively enhances the strength of the alloy.The low stacking fault energy promotes the toughening of NiCoV but makes the plasticity of the alloy decrease.Still,the formation of annealed twins effectively increases the plasticity,which makes the alloy harder but does not reduce the plasticity too much.By comparing the experimental properties,（NiCoV）93Ga7showed the best mechanical properties at the annealing temperature of 900℃,yield strength,tensile strength and elongation of 906 MPa,1321 MPa and21.36 %,respectively.

关键词： Annealing treatment High entropy alloy Mechanical properties Precipitation strengthening Twin strengthening

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