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Evaluating changes in ecological land and effect of protecting important ecological spaces in China

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Journal of Geographical Sciences 2021年第9期31卷 1245-1260页

作者： GAO Jixi LIU Xiaoman WANG Chao WANG Yong fu zhuo HOU Peng LYU Na Ministry of Ecology and Environment Center for Satellite Application on Ecology and Environment Beijing 100094China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

It is important to quantitatively analyze the effects of protection of important ecological spaces in China to ensure national ecological *** considering changes in the ecological land,this study examines the effects of protecting three types of important natural ecological spaces in China from 1980 to ***,considering important ecological spaces and their surroundings yields differences in the effects of protection between internal and external spaces,where this can provide a scientific basis for the categorization and zoning of China’s *** results show the following:(1)In 2018,the ratio of ecological land to important natural ecological spaces accounted for 92.64%.This land had a good ecological background that reflects the developmental orientation of important ecological spaces.(2)From 1980 to 2018,the area of ecological land in important ecological spaces shrank but the rate of reduction was lower than the national average,which shows the positive effect of regulating construction in natural ecological *** restorative effects of ecological projects to convert farmland into forests and grasslands have been *** expanded ecological land is mainly distributed in areas where such projects have been implemented,and the reduced area is concentrated in grain-producing areas of the Northeast China Plain and agricultural oases of *** the future,the government should focus on strengthening the management and control of these areas.(3)The area ratio of ecological land was the highest in national nature *** rate of reduction in its area was the lowest and the trend of reduction was the smallest in national nature reserves,which reflects differences in the status of ecological protection among different spaces.(4)The ratio of ecological land to important ecological spaces was higher than that in the surrounding external space,and the rate of reduction in it was ***,the effects of internal and external protection

关键词： ecological spaces ecological land spatial and temporal dynamic changes protection effect categorized and zoned governance

Impact of immunotherapy on liver metastasis

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 1969-1972页

作者： zhuo fu Ming-Wei Wang Ya-Hui Liu Yan Jiao Medical College Inner Mongolia Minzu UniversityTongliao 028000Inner Mongolia Autonomous RegionChina Ministry of Health Key Laboratory of Radiobiology School of Public Health of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Hepatobiliary and Pancreatic Surgery General Surgery CenterThe First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

This editorial discusses the article“Analysis of the impact of immunotherapy efficacy and safety in patients with gastric cancer and liver metastasis”published in the latest edition of the World Journal of Gastrointestinal *** has achieved outstanding success in tumor ***,the presence of liver metastasis(LM)restrains the efficacy of immunotherapy in various tumors,including lung cancer,colorectal cancer,renal cell carcinoma,melanoma,and gastric cancer.A decrease in CD8+T cells and nature killer cells,along with an increase in macrophages and regulatory T cells,was observed in the microenvironment of LM,leading to immunotherapy *** studies are necessary to determine the best strategy for enhancing the effectiveness of immunotherapy in patients with LM.

关键词： Immunotherapy Liver metastasis Tumor microenvironment Resistance T cells

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World Journal of Gastroenterology 2017年第43期23卷 7746-7755页

作者： Yun-Wei Guo Hui-Biao Miao zhuo-fu Wen Jie-Ying Xuan Hao-Xiong Zhou Department of Gastroenterology the Third Affiliated Hospital of Sun Yat-Sen University

AIM To focus on procedure-related complications,evaluate their incidence,analyze the reasons and discuss the *** Overall,628 endoscopic gastric variceal obturation(EGVO) procedures(case-times) with NBC were performed in 519 patients in the Department of Endoscopy of the Third Affiliated Hospital of Sun Yat-Sen University from January 2011 to December 2016. The clinical data of patients and procedure-related complications of EGVO were retrospectively *** In the 628 EGVO procedures,sticking of the needle to the varix occurred in 9 cases(1.43%),including 1 case that used lipiodol-diluted NBC and 8 cases that used undiluted NBC(P = 0.000). The needle was successfully withdrawn in 8 cases. Large spurt bleeding occurred in one case,and hemostasis was achieved by two other injections of undiluted glue. The injection catheter became blocked in 17 cases(2.71%) just during the injection,and 4 cases were complicated with the needle sticking to the varix. Large glue adhesion to the endoscope resulted in difficulty withdrawing the endoscope in 1 case. Bleeding from multiple sites was observed in the esophagus and gastric cardia after the endoscope was withdrawn. Hemostasis was achieved by 1% aethoxysklerol injection and intravenous somatostatin. The ligation device stuck to the varices in two cases during the subsequent endoscopic variceal ligation. In one case,the ligation device was successfully separated from the esophageal varix after all bands were released. In another case,a laceration of the vein and massive bleeding were observed. The bleeding ceased after 1% aethoxysklerol *** Although EGVO with tissue glue is usually safe and effective,a series of complications can occur during the procedure that may puzzle endoscopists. There is no standard operating procedure for addressing these complications. The cases described in the current study can provide some reference for others.

关键词： Endoscopic gastric variceal obturation Tissue glue N-butyl-2-cyanoacrylate Complications

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基于第一性原理的镧掺杂氧化锌的性质研究

原子与分子物理学报 2025年第1期42卷 163-170页

作者：王馨悦许钟华吴光成谢富焯杨坚祝辉亚陈春燕广西民族师范学院数理与电子信息工程学院崇左532200

本文采用第一性原理计算方法开展La掺杂ZnO的缺陷研究,分析了La在ZnO中的不同占位缺陷:替换位和间隙位缺陷的形成能、能带和态密度;证明了La掺杂ZnO的生长过程中,La替换Zn原子形成替换位缺陷的可能性要比进入间隙位形成间隙位缺陷大,而... 详细信息

本文采用第一性原理计算方法开展La掺杂ZnO的缺陷研究,分析了La在ZnO中的不同占位缺陷:替换位和间隙位缺陷的形成能、能带和态密度;证明了La掺杂ZnO的生长过程中,La替换Zn原子形成替换位缺陷的可能性要比进入间隙位形成间隙位缺陷大,而在形成替换位缺陷时,选择富氧的生长环境要比富锌的生长环境好,替换位缺陷有助于提高ZnO的导电能力,改善ZnO的性能.本文的研究结果能够为La掺杂ZnO的实验和应用提供一定的理论参考.

关键词：氧化锌稀土元素能带电子态密度第一性原理

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Spectral filtering of dual lasers with a high-finesse length-tunable cavity for rubidium atom Rydberg excitation

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Chinese Physics B 2021年第7期30卷 261-268页

作者： Yang-Yang Liu zhuo fu Peng Xu Xiao-Dong He Jin Wang Ming-Sheng Zhan State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

We propose and demonstrate an alternative method for spectral filtering and frequency stabilization of both 780-nm and 960-nm lasers using a high-finesse length-tunable cavity(HFLTC).Firstly,the length of HFLTC is stabilized to a commercial frequency ***,the two lasers are locked to this HFLTC using the Pound–Drever–Hall(PDH)method which can narrow the linewidths and stabilize the frequencies of both lasers ***,the transmitted lasers of HFLTC with each power up to about 100μW,which act as seed lasers,are amplified using the injection locking method for single-atom Rydberg *** linewidths of obtained lasers are narrowed to be less than 1 k Hz,meanwhile the obtained lasers'phase noise around 750 k Hz are suppressed about 30 d *** the spectrally filtered lasers,we demonstrate a Rabi oscillation between the ground state and Rydberg state of single-atoms in an optical trap tweezer with a decay time of(67±37)μs,which is almost not affected by laser phase *** found that the maximum short-term laser frequency fluctuation of a single excitation lasers is at~3.3 k Hz and the maximum long-term laser frequency drift of a single laser is~46 k Hz during one *** work develops a stable and repeatable method to provide multiple laser sources of ultra-low phase noise,narrow linewidth,and excellent frequency stability,which is essential for high precision atomic experiments,such as neutral atom quantum computing,quantum simulation,quantum metrology,and so on.

关键词： laser frequency stabilization spectral filtering Rydberg state rubidium atom

需求可离散拆分车辆路径问题及其禁忌搜索算法

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哈尔滨工程大学学报 2019年第3期40卷 525-533页

作者：邱萌符卓中南大学交通运输工程学院湖南长沙410075

针对客户需求常以若干离散订单(批次)构成的问题特性,本文给出需求可离散拆分车辆路径问题的描述及数学模型。对比需求可连续拆分的问题类型,对该问题性质进行了研究,分析提出问题解的特性。本文提出求解该问题的禁忌搜索算法,针对同客... 详细信息

针对客户需求常以若干离散订单(批次)构成的问题特性,本文给出需求可离散拆分车辆路径问题的描述及数学模型。对比需求可连续拆分的问题类型,对该问题性质进行了研究,分析提出问题解的特性。本文提出求解该问题的禁忌搜索算法,针对同客户的不同订单(批次)需求,设计两种特殊操作以避免不必要的路径成本,加快搜索速度并增强算法搜索性能。计算结果与现有方法结果进行了比较,表明所提出的算法可以找到更好的解决方案。

关键词：车辆路径问题需求可拆分离散拆分禁忌搜索邻域操作物流配送

Responses of soil nutrient to driving mechanism in Taihu Lake basin in last 20 years

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Journal of Geographical Sciences 2001年第1期11卷 92-98页

作者： CHEN fu, PENG Bu-zhuo, BAO Hao-sheng (Department of Urban and Resources Science, Nanjing University, Nanjing 210093, China) Department of Urban and Resources Science Nanjing University Nanjing China

The objectives of this study is to understand the changing law of soil nutrient quality in Taihu Lake basin, Yangtze Delta in last 20 years, and reveal the relationship between soil nutrient changes and human driving forces in regional level over long period of time. Experiment on long-term collecting samples was conducted to study changes of soil organic matter, total N, available N, available P and available K in Dongting town, Wuxi city during the last 20 years. The paper analyses the co-relationship of the fluctuation of soil nutrient and state policy, cultivating practice, agricultural input, and per hectare agricultural net income. The results showed that at first the content of soil organic matter increased, then decreased, and increased again. The content of total N and available N steadily increased. The content of available K and available P steadily decreased. The authors found that the influence of state policy and cultivating practice on soil nutrient quality index (SNQI) is obvious, agricultural input and SNQI are positively correlated, and per hectare agricultural net income and SNQI are negatively correlated.

关键词： soil nutrient SNQI human driving mechanism Taihu Lake basin

A new construction method of QC-LDPC codes with low error floor based on EETS and Zig-Zag

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Optoelectronics Letters 2019年第4期15卷 292-296页

作者： ZHENG De-meng YUAN Jian-guo WANG Hong-sen FAN fu-zhuo YUAN Meng Chongqing Key Laboratory of Photoelectronic Information Sensing and Transmitting Technology Chongqing University of Posts and Telecommunications

Aiming at the problem that quasi-cyclic low density parity check(QC-LDPC) codes may have the error floor in the high signal to noise ratio(SNR) region, a new construction method of the QC-LDPC codes with the low error floor is proposed. The basic matrix of the method is based on the progressive edge growth(PEG) algorithm and the improved eliminate elementary trapping sets(EETS) algorithm so as to eliminate the elementary trapping sets in the basic matrix,then the Zig-Zag method is used to construct the cyclic shift matrix which is used to extend the basic matrix in order to construct the parity check matrix. The method not only can improve the error floor in the high SNR region, but also can flexibly design the code length and code rate. The simulation results show that at the bit error rate of 10-6, the PEG-trapping-Zig-Zag(PTZZ)-QC-LDPC(3024,1512) codes with the code rate of 0.5, compared with the PEG-Zig-Zag(PZZ)-QC-LDPC(3024,1512) codes and the PEG-QC-LDPC(3024,1512) codes, can respectively improve the net coding gain of 0.1 dB and 0.16 dB. The difference among the bit error rate performance curves will become better with the increase of the SNR. In addition, the PTZZ-QC-LDPC(3024,1512) codes have no error floor above the SNR of 2.2 dB.

关键词： quasi-cyclic low density parity check(QC-LDPC) signal to noise ratio(SNR) progressive edge growth(PEG)

Endoscopic variceal ligation caused massive bleeding due to laceration of an esophageal varicose vein with tissue glue emboli

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World Journal of Gastroenterology 2014年第42期20卷 15937-15940页

作者： Xiu-Qing Wei Hua-Ying Gu Zhi-E Wu Hui-Biao Miao Pei-Qi Wang zhuo-fu Wen Bin Wu Department of Gastroenterology the Third Affiliated Hospital of Sun Yat-Sen University

Endoscopic variceal obturation of gastric varices with tissue glue is considered the first choice for management of gastric varices, and is usually safe and effective. However, there is still a low incidence of complications and some are even fatal. Here, we present a case in which endoscopic variceal ligation caused laceration of the esophageal varicose vein with tissue glue emboli and massive bleeding after 3 mo. Cessation of bleeding was achieved via variceal sclerotherapy using a cap-fitted gastroscope. Methods of recognizing an esophageal varicose vein with tissue glue plug are discussed.

关键词： Gastroesophageal varices Variceal bleeding Laceration Varices ligation Tissue glue injection