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Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China

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Acta Geochimica 2024年第3期43卷 441-458页

作者： Qing-Qing Zhang you-wei chen Jian-Feng Gao State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South *** Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained *** deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and *** study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and *** element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge *** Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic *** low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization *** contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten *** contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°*** in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH ***,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit.

关键词： Quartz Xingluokeng Tungsten deposit Trace elements South China

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茶蚜龄期划分及各龄期形态特征的识别

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应用昆虫学报 2024年第1期61卷 197-205页

作者：张方梅尤伟晨陈磊耿书宝郭世保乔利周洲陈俊华信阳农林学院信阳464000

【目的】明确茶蚜Toxoptera aurantia虫龄鉴别特征,为准确、快速识别茶蚜龄期提供理论基础。【方法】利用体式显微镜分别对两翅型茶蚜各龄期若蚜和成蚜的体长、体宽、头壳宽、触角长度、腹管长度、尾片长度和后足胫节长度7项指标进行测... 详细信息

【目的】明确茶蚜Toxoptera aurantia虫龄鉴别特征,为准确、快速识别茶蚜龄期提供理论基础。【方法】利用体式显微镜分别对两翅型茶蚜各龄期若蚜和成蚜的体长、体宽、头壳宽、触角长度、腹管长度、尾片长度和后足胫节长度7项指标进行测量。【结果】无翅型和有翅型茶蚜的7个指标在各虫龄中均存在差异。不同龄期无翅型茶蚜体长、后足胫节长度和有翅型茶蚜后足胫节长度在不同龄期若蚜和成蚜间存在部分重叠或无,可用于鉴定茶蚜虫龄。此外,翅基发育程度可用于区分3和4龄若蚜,触角节数可用于区分1和2龄若蚜与其他龄期蚜虫,尾片的外部形态特征可用于区分若蚜和成蚜。【结论】无翅型茶蚜的龄期鉴定主要依据其体长和后足胫节长度,而有翅型茶蚜的龄期鉴定主要依据其后足胫节长度,同时结合胸部翅基发育、不同龄期触角节数及尾片形态等,可准确识别两翅型不同龄期的茶蚜。

关键词：茶蚜虫龄翅型形态特征

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Surgery for Cronkhite-Canada syndrome complicated with intussusception:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2022年第2期14卷 200-210页

作者： Jie Dong Tian-Shi Ma Jiang-Feng Tu you-wei chen Cancer Center Department of GastroenterologyZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina Cancer Center Department of PathologyZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina

BACKGROUND Cronkhite-Canada syndrome(CCS)is a rare nonhereditary disease with a syndrome of multiple gastrointestinal polyps,skin pigmentation,hair loss,and fingernail/toenail *** is a serious condition with an occurrence rate of 5%in adults,which is mainly caused by intestinal tumors or other intestinal *** SUMMARY A 57-year-old woman was admitted to our hospital due to abdominal distension and pain for the past *** nausea and vomiting symptoms had been aggravated for the past *** transoral enteroscopy results one year prior showed chronic erosive gastritis protuberans,duodenitis,and *** had sparse body hair and brown pigmentation on the skin of her hands and bilateral anterior *** nails of both hands were pale and lacked luster,and the fingernail of her ring finger was longitudinally *** showed extensive diffuse polypoid lump changes in the gastric body and antrum,of 0.5-3 cm in *** showed multiple polypoid mucosal bulges in the terminal ileum and multiple polyps(0.3-5 cm)throughout the *** patient was diagnosed with CCS and underwent partial excision of the polyps,but she refused hormone *** month later,the patient complained of nausea and vomiting,accompanied by abdominal pain and inability to pass gas or ***-enhanced computed tomography of the abdomen showed gastrointestinal polyposis and ileocecal *** underwent stomach and bowel *** CCS,as a rare disease with poor prognosis,should be treated *** steroids,immunosuppressive agents,and biological agents were not applied;thus,the patient’s symptoms quickly progressed,and intussusception *** had to undergo *** compliance may lead to a better prognosis.

关键词： Cronkhite-Canada syndrome Intussusception Treatment Prognosis Surgery Case report

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Surgical resection of intradural extramedullary tumors in the atlantoaxial spine via a posterior approach

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World Journal of Clinical Cases 2022年第1期10卷 62-70页

作者： Di-Hua Meng Jia-Qi Wang Kun-Xue Yang wei-you chen cheng Pan Hua Jiang Department of Spine Surgery the First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi ProvinceChina

BACKGROUND The anatomical features of the atlantoaxial spine increase the difficulty of complete and safe removal of atlantoaxial intradural extramedullary(IDEM)*** concerning surgical interventions via a posterior approach are *** To investigate the safety and efficacy of atlantoaxial IDEM tumor resection using a one-stage posterior *** We retrospectively analyzed clinical databases for one-stage atlantoaxial IDEM tumor resection via a posterior approach between January 2008 and January *** analyzed data included tumor position,histopathological type,pre-and postoperative Japanese Orthopedic Association(JOA)scores and Nurick grades,postoperative complication and recurrence *** A total of 13 patients who underwent C1-C2 Laminectomy and/or unilateral facetectomy via the posterior approach were enrolled in the *** all cases reviewed,total tumor resection and concomitant C1-C2 fusion were *** average follow-up was 35.3±6.9 mo(range,26-49 mo).A statistically significant difference was noted between the preoperative JOA score(11.2±1.1)and the score at the last final follow-up(15.6±1.0)(P0.05).No mortalities,severe complications or tumor recurrence were observed during the follow-up *** Total resection of atlantoaxial IDEM tumors is feasible and effective via a posterior *** reconstruction should be considered to avoid iatrogenic kyphosis and improve spinal stability and overall clinical outcomes.

关键词： Atlantoaxial spine Cervical spine Extramedullary tumors Intardural tumer Posterior approach Surgical resection

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Scientific publications on orthopedic surgery from three major East Asian countries(2012-2021)

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世界骨科杂志:英文版 2023年第8期14卷 641-650页

作者： wei-you chen Xin Xiao cheng Pan Fei-Hong Huang Hong-Yuan Xu Qing-Jun wei Hua Jiang Division of Spine Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Orthopedic Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND East Asia is the most dynamic region in the world and includes three major countries:Japan,South Korea and *** to rapid economic growth,orthopedics research in East Asia has achieved great advances during the past 10 ***,the current status of orthopedic research in Japan,South Korea and China is still *** To understand the current status of orthopedic research in Japan,South Korea,and *** Journals listed in the“Orthopedics”category of Science Citation Index Expanded subject categories were *** PubMed and Web of Knowledge electronic databases were searched to identify scientific publications from the selected journals written by researchers from Japan,South Korea and China.A systematic analysis was conducted to analyze orthopedic research articles published in the three countries based on the number of articles,study design,impact factors(IFs)and ***,we also ranked the top 10 countries worldwide with the highest publications in the past 10 ***,we ranked the top 10 countries with the highest number of publications in the world in the past 10 *** analyses were performed using SPSS 20.0 software(SPSS Inc.,Chicago,IL,United States),and statistical results are given in Tables and *** Kruskal-Wallis test and the Mann-Whitney test were used to detect differences between *** tendency regarding the number of articles was analyzed by curvilinear regression.A two-tailed P<0.05 was considered *** From 2012-2021,a total of 144518 articles were published in the 86 selected orthopedic *** this period,the number of worldwide published orthopedic articles has shown an annual increasing trend.A total of 27164 orthopedic research articles were published by Japan,South Korea and China during the past 10 years;44.32%were from China,32.98%were from Japan,and 22.70%were from South *** 2012 to 2021,the annual number of articles markedly in

关键词： Japan South Korea China Medical publication Orthopedics Research

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Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： chen chen QUAN wei SHAO Zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)

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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data

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Journal of Integrative Agriculture 2024年第4期23卷 1164-1178页

作者： Yunping chen Jie Hu Zhiwen Cai Jingya Yang wei Zhou Qiong Hu Cong Wang Liangzhi you Baodong Xu Macro Agriculture Research Institute College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China Key Laboratory of Agricultural Remote Sensing Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China International Food Policy Research Institute NWWashingtonD.C.20005USA

Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural ***,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy *** this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)*** PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature *** on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover ***,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice ***,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively

关键词： ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data

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Intermittent melena and refractory anemia due to jejunal cavernous lymphangioma:A case report

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1208-1214页

作者： Kai-Rui Liu Sheng Zhang wei-Run chen you-Xing Huang Xu-Guang Li Department of Abdominal Surgery The Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510000Guangdong ProvinceChina Department of General Surgery The Affiliated Brain Hospital of Guangzhou Medical UniversityGuangzhou 510000Guangdong ProvinceChina Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and The Ministry of Education of China Guangzhou Medical UniversityGuangzhou 510000Guangdong ProvinceChina

BACKGROUND Lymphangiomas in the gastrointestinal tract are extremely rare in *** a benign lesion,small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive ***,lymphangiomas can give rise to complications such as abdominal pain,bleeding,volvulus,and ***,we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male *** SUMMARY A 66-year-old man presented with intermittent melena,fatigue and refractory anemia nine months *** and colonoscopy were performed many times and revealed no apparent *** management,including transfusion,hemostasis,gastric acid secretion inhibition and symptomatic treatment,was performed,but the lesions tended to recur shortly after ***,the patient underwent capsule endoscopy,which revealed a more than 10 cm lesion accompanied by active *** singleballoon enteroscopy and biopsy,a diagnosis of jejunal cavernous lymphangioma was confirmed,and the patient underwent surgical *** complications or recurrences were observed *** Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal *** endoscopy and single-balloon enteroscopy can facilitate *** resection is an effective management method.

关键词： Intermittent melena Refractory anemia Capsule endoscopy Single-balloon enteroscopy Jejunal cavernous lymphangioma Enterectomy Case report

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Is the Cape Stone Forest in Shantou City formed by wave erosion? A comparison of the pedestal rocks on the coasts and the mountains of Queshi in eastern Guangdong, China

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Journal of Mountain Science 2024年第5期21卷 1447-1463页

作者： chen Min WANG wei School of Geography South China Normal UniversityGuangzhou 510631China

Cape Stone Forest is a group of granite rock pillars(pedestal rocks) towering over Shilin Lake, on the southern shore of Shantou Bay in eastern Guangdong, China. The rock pillars were previously identified as sea stacks because they have marine notch-like concave sidewalls at their base, and more importantly, the lake is immediately adjacent to the bay, which is exposed to the open sea. However, rock pillars similar in shape and size can also be found at the top of Queshi Mountain, which is only about 300 meters northwest of the lake and about 85 meters above sea level. Therefore, the marine origin of Cape Stone Forest is seriously questioned. In this study, 3D imagery and drone technology were used to collect data in the investigations without direct manual measurements in the water or on the mountain. It shows that the concave sidewalls of the rock pillars in the lake and on the mountains occur at different heights and are exposed to different directions, while a natural sea stack on Mayu Island at the mouth of Shantou Bay has a horizontal notch parallel to the sea level, although the granite rock of the sea stack is the same as that of the lake and the mountains. The eastern side of the island, where the sea stack is located, is exposed to the open sea but blocks large waves for the rock pillars in the lake. Therefore, the origin of Cape Stone Forest cannot be explained by wave-based mechanisms. The only satisfactory explanation that takes into account all the field evidence is that the narrow rock pillars of the lake and mountain were formed by chemical weathering that penetrated closely the spaced joints of the granite rock, and the notch-like concave sidewalls were formed by more effective chemical weathering at the base of the pillars.

关键词： Pedestal rock Granite Closely spaced joints Wave erosion Chemical weathering

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2D all-organic perovskites refine flexible electronics

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Science China Materials 2024年第7期67卷 2365-2366页

作者： wei Zhou Bing chen College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China

Recent years have witnessed a paradigm shift with the advent of perovskites,a class of materials with a distinct CaTiO_(3)-type crystalline structure that show remarkable promise across a wide array of applications,including photovoltaics,photodetectors,lighting,lasers,and so *** them,the development of two-dimensional(2D)perovskites has garnered significant attention due to their tunable structures(mainly Dion-Jacobson and Ruddlesden-Popper structures)and enhanced stability in comparison with their 3D counterparts[1].Amidst the burgeoning research on perovskites,on the other side,all-organic perovskites stand out as a particularly intriguing subset[2].Unlike traditional perovskites that typically comprise all-inorganic(e.g.,CsPbBr_(3))or organic-inorganic hybrid components(e.g.,(PEA)_(2)PbI_(4)),all-organic perovskites are composed entirely of carbon-or nitrogen-based molecules.

关键词： perovskite inorganic entirely

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