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Magma Origin and Evolution of Tengchong Cenozoic Volcanic Rocks from West Yunnan,China:Evidence from Whole Rock Geochemistry and nd-Sr-Pb Isotopes

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Acta Geologica Sinica(English Edition) 2012年第4期86卷 867-878页

作者： LI Dapeng LUO Zhaohua LIU Jiaqi CHEN Yuelong JIN ye State Key Laboratory of Geological Processes and Mineral Resources School of Earth Science and ResourcesChina University of Geosciences Institute of Geology and Geophysics Chinese Academy of Sciences School of Ocean Sciences China University of Geosciences

Tengchong Cenozoic volcanics that have record key information on the tectonic evolution and mantle features of the southeast margin of the Tibetan Plateau are of great importance because of its unique eruption history spanning the entire Quaternary period. Magma origin and evolution of Tengchong Cenozoic volcanic rocks were studied on the basis of nd-Sr-Pb isotope and major and trace element data from different eruptions in the Ma＇anshan area. Different samples within one eruption show relative identical lithologies, chemical and isotopic compositions. However, the geochemical features for the five eruptions are distinct from each other. These volcanic rocks show low Mg# values （〈45）, moderate to high fractionation of LREEs and HREEs, and enrichment of Pb and Ba and depletion of Nb. Tengchong Cenozoic volcanic rocks were derived from an enriched mantle based on nd-Sr-Pb isotopic studies. And lines of evidence show that crustal contamination should be involved before the eruption of different periods of Tengchong Cenozoic volcanic rocks. Older subducted components may be responsible for adakite recycling at various stages of evolution, which results in the origin of the enriched mantle source magma accounting for the isotopic features of Tengchong Cenozoic volcanic rocks. Segregated primitive magma pulsating injected into magma chamber, fractional crystallized and contaminated with crust component. Finally, magmas with distinct chemical and isotopic compositions for each eruption formed. The extension of the northeast segment of the Yingjiang tectonic belt triggered the pulsating eruption of the Cenozoic volcanics in the Tengchong area.

关键词： Cenozoic volcanism nd-Sr-Pb isotopes geochemistry Tengchong

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Room-temperature infrared photodetectors with hybrid structure based on two-dimensional materials

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Chinese Physics B 2019年第1期28卷 82-100页

作者： Tiande Liu Lei Tong Xinyu Huang Lei ye School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

Two-dimensional(2D) materials, such as graphene, transition metal dichalcogenides(TMDs), black phosphorus(BP),and related derivatives, have attracted great attention due to their advantages of flexibility, strong light–matter interaction,broadband absorption, and high carrier mobility, and have become a powerful contender for next-generation infrared photodetectors. However, since the thickness of 2D materials is on the order of nanometers, the absorption of 2D materials is very weak, which limits the detection performance of 2D materials-based infrared photodetectors. In order to solve this problem, scientific researchers have tried to use optimized device structures to combine with 2D materials for improving the performance of infrared photodetectors. In this review, we review the progress of room-temperature infrared photodetectors with hybrid structure based on 2D materials in recent years, focusing mainly on 2D–nd(n = 0, 1, 2) heterostructures, the integration between 2D materials and on-chip or plasmonic structure. Finally, we summarize the current challenges and point out the future development direction.

关键词： two-dimensional materials heterostructure infrared photodetectors

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纤维带与无头加压螺钉治疗第1,2跖骨近端粉碎性骨折Lisfranc损伤

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中国组织工程研究 2025年第9期29卷 1803-1809页

作者：黄浩波梁馨元叶国忠谢庆祥苏博源广州中医药大学东莞医院(东莞市中医院) 广东省东莞市523000

背景:Lisfranc韧带是维持足部横弓与纵弓的重要结构,Lisfranc损伤为一种严重的中足损伤。Lisfranc韧带损伤是复杂的,其治疗以及首选的固定方法有争议。目的:比较钢板联合Suturetape与钢板联合无头加压螺钉治疗第1,2跖骨近端粉碎性骨折Li... 详细信息

背景:Lisfranc韧带是维持足部横弓与纵弓的重要结构,Lisfranc损伤为一种严重的中足损伤。Lisfranc韧带损伤是复杂的,其治疗以及首选的固定方法有争议。目的:比较钢板联合Suturetape与钢板联合无头加压螺钉治疗第1,2跖骨近端粉碎性骨折Lisfranc损伤的短期疗效。方法:回顾性分析东莞市中医院骨七科2019年1月至2022年6月因第1,2跖骨近端粉碎性骨折Lisfranc损伤患者48例,其中25例采用钢板联合Suture tape固定(观察组),23例采用钢板联合无头加压螺钉固定(对照组)。术前参照影像学资料,根据Myerson分类系统进行分型;术后随访根据骨折愈合时间、目测类比评分、美国足踝外科学会标准评估足功能恢复情况,并对两组术后并发症进行比较分析。结果与结论:①两组患者均顺利完成手术并获得随访,随访时间12-36个月,平均(18.0±5.42)个月;②两组患者手术时间、术中出血量比较差异均无显著性意义(P>0.05);③观察组较对照组骨折愈合时间稍长,差异有显著性意义(P0.05),考虑与样本量偏少有关;⑦提示对于第1,2跖骨近端粉碎性骨折Lisfranc损伤,实施钢板联合Suture tape内固定治疗Lisfranc关节损伤效果可靠,可改善患者足关节功能,且具有手术创伤小、术后并发症少、远期医源性创伤性关节炎风险低的优势,较无头加压钉更有利于足功能的恢复。

关键词：第1,2跖骨近端粉碎性骨折 Lisfranc损伤钢板无头加压螺钉 Suturetape 内固定

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Laser Properties of nd_2O_3 Doped Na_2O–CaO–SiO_2 Transparent Glass-Ceramics for Space Solar Energy

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Journal of Materials Science & Technology 2016年第6期32卷 583-586页

作者： Shuming Wang Fenghua Kuang Qing ye Yanxin Wang Minghui Tang Changchun Ge Department of Materials Science and Engneering.University of Science&Technology Beijing Beijing 100083.China

A series of Na20-CaO-SiO2 glass ceramics containing different content of nd3＋ ions were prepared by the method of high temperature melting and subsequent crystallization. The absorption, excitation and emis- sion spectra of these glass ceramics were investigated; effects of nd3＋ content and crystallization behavior on the laser properties of this material had been studied. The results show that the emission bands origi- nating from the 4F3/2 state of nd3＋ were firstly enhanced with the increase of the nd2O3 doping content and the crystallinity degree, and then decreased with more doping content and deepened crystalliza- tion. The possible reasons of this phenomenon were analyzed. Research will be favored to promote the development of glass ceramics laser materials for space solar energy.

关键词： Transparent glass-ceramics Laser property Space solar energy

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Luminescent properties of a new nd^(3+)-doped complex with two different carboxylic acids and pyridine derivative

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Rare Metals 2013年第5期32卷 490-495页

作者： Yun-Xia ye Li-Hua Wei Wei-Chen Mei Chen Yin-Qun Hua School of Mechanical Engineering Jiangsu University Institute of Laser Technology Jiangsu University School of Material Engineering Jiangsu University

A new nd3＋-doped organic complex featuring two different perfluorinated carboxylic acids as the first ligand and pyridine derivative 2-amino-3-chloro-5-（tri- fluoromethyl）pyridine as the second ligand was designed and synthesized. Successful coordination between the ligands and central rare earth ions was confirmed by Fourier transform infrared spectroscopy （FT-IR） spectra, 1H nuclear magnetic resonance （1H NMR） spectra, and UV spectra, and the synthesized complex is inferred to be eight-coordinate structure. Solution of the complex dis- solved in DMSO-d6 was prepared and then its fluorescence spectrum, UV-Vis-NIR absorption spectrum, and fluorescence decay curve were tested. The fluorescent lifetime is about 7 txs. Based on the above experimental research, Judd-Ofelt analysis was carried out, and the results indi- cate that appropriate coordination environment around nd3＋ in this solution results in a high fluorescent quantum efficiency 2 % and a large stimulated emission cross-section about 3.2 × 10^-20 cm^2 at 1,064 nm.

关键词： nd Organic solution Liquid laser Quantum efficiency Judd-Ofelt theory

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Paleozoic post-collisional magmatism and high-temperature granulite-facies metamorphism coupling with lithospheric delamination of the East Kunlun Orogenic Belt,NW China

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Geoscience Frontiers 2022年第1期13卷 96-113页

作者： Qian Wang Jiao Zhao Chuanlin Zhang Shengyao Yu Xiantao ye Xiaoqiang Liu College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China College of Oceanography Hohai UniversityNanjing 210098China Key Lab of Submarine Geosciences and Prospecting Techniques MOEInstitute for Advanced Ocean StudyCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China

Lithosphere extension and upwelling of asthenosphere at post-collisional stage of an orogenic cycle generally induce diverse magmatism and/or associated high-temperature metamorphism. Nevertheless, the intimate coexistence of post-collisional magmatic activity and high-temperature metamorphism is *** this contribution, a lithological assemblage composing of diverse magmatic rocks deriving from distinct magma sources and coeval high-temperature metamorphism was identified in eastern ***, ages, mineral chemistry and whole-rock geochemistry demonstrated that those intimately coexistent diverse rocks were genetically related to post-collisional extension. The garnet-bearing mafic granulites in Jinshuikou area interior of the East Kunlun Orogenic Belt are mainly composed of garnet,orthopyroxene, and plagioclase, with peak metamorphic P–T conditions of ~ 701–756 ℃and 5.6–7.0 kbar,representing a granulite-facies metamorphism at 409.7 ± 1.7 Ma. The diverse contemporaneous magmatic rocks including hornblendites, gabbros and granites yield zircon U–Pb ages of 408.6 ± 2.5 Ma,413.4 ± 4.6 Ma, and 387–407 Ma, respectively. The hornblendites show N-MORB-like REE patterns with(La/Sm)Nvalues of 0.85–0.94. They have positive zircon εHf(t) values of 0.1–4.9 and whole-rock εnd(t) values of 3.9–4.7 but relatively high(^(87)Sr/^(86)Sr)_(i)values of 0.7081 to 0.7088. These features demonstrate that the hornblendites derived from a depleted asthenospheric mantle source with minor continental crustal materials in source. As for the gabbros, they exhibit arc-like elemental signatures, low zircon εHf(t) values(-4.3 to 2.5) and variable whole-rock εnd(t) values(-4.9 to 1.2) as well as high(^(87)Sr/86 Sr)ivalues(0.7068 to 0.7126), arguing for that they were originated from partial melting of heterogeneous lithospheric mantle anteriorly metasomatized by subducted-sediment released melts. Geochemistry of the granites defines their strongly peraluminous S-type signatures. Zircon

关键词： East Kunlun orogenic belt Post-collisional extensional collapse Magmatism High-temperature metamorphism Crust-mantle interaction

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Zircon SHRIMP U–Pb geochronology,geochemistry,and geological significance of dacite in the Zhesang gold district,southeast Yunnan Province,China

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Acta Geochimica 2023年第2期42卷 290-308页

作者： Bo Wang Jiasheng Wang Jinlong Li Hao Fu Yuehua Ma Bin ye Earth Science Department of Land Resources College Kunming University of Science and TechnologyKunming 650093China Yunnan Bureau of Coalfield Geology Kunming 650034China

The Late Paleozoic and Mesozoic tectonic framework of the Nanpanjiang Basin has much been ***,the middle-acid volcanic rock,dacite,exposed to the Zhesang gold district,southeast Yunnan Province,has been *** results show that the dacite belongs to a calc-alkaline series,SiO_(2)contents range from 62.79 to 76.66 wt%.Zircon SHRIMP U–Pb dating of dacite demonstrates that they were formed in the Early Triassic(247.8±1.7 Ma,MSWD=1.2).All samples exhibit enrichment in LILE(***,K,Th,and U),and depletion in HFSE(***,Ta,and Ti),which has the geochemical affinity of I-type ***–La/Sm and La–La/Yb discrimination diagrams show that the partial melting,mainly of the mafic lower crust,of rocks,plays a major role in the formation *** dacite has low initial ^(87)Sr/^(86)Sr ratios(0.706954 to 0.708589)and negative ε_(nd)(t)values(-11.77 to-10.88).Zircons in dacite have ε_(Hf)(t)values of-16.2 to-8.3,and the two-stage Hf model ages are 1799–2301 Ma,mostly concentrated between 1800 and 1900 Ma,indicating that the magma source area is the reconstructed ancient lower crust mixed with some mantle materials,and crystal fractionation process underwent in the late stage of magma *** study reveals that the arc-volcanic rocks of the Early Triassic in the southern margin of the Nanpanjiang Basin were formed by the subduction of the Late Paleozoic ocean basin within the border region between China and Vietnam.

关键词： Dacite Zircon SHRIMP U–Pb geochronology Sr–nd–Hf isotope Geochemistry Arcvolcanic rock Late Paleozoic ocean basin

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Future challenges and solutions for safety in China:China CDC’s exploration of injury prevention strategies

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Global Health Journal 2018年第2期2卷 14-23页

作者： Leilei Duan Pengpeng ye Linhong Wang National Center for Chronic and Noncommunicable Diseases Control and Prevention Chinese Center for Disease Control and PreventionBeijing 100050China

As an important component of worldwide injury prevention,China has made great contribution to the *** is serving as a model for other countries in the world,especially developing countries,and China’s experience has great implications for *** the description of the present situation and trends of China’s injury prevention work and review for its development history,this paper has also introduced the existing issues and the current challenges,and informed the e orts of the sta in related eld to nd solutions from di erent *** of them jointly boosted the development of global injury prevention.

关键词： injury prevention and control Chinese Center for Disease Control and Prevention National Center for Chronic and Non-communicable Disease Control and Prevention

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COVID-19/Tuberculosis Co-Infection at the Epidemic Treatment Center (ETC) of Saint-Louis (Senegal): About 9 Cases

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Advances in Infectious Diseases 2024年第1期14卷 56-66页

作者： Alassane Dièye Moustapha Diedhiou Papa Latyr Junior Diouf Mba Bambo Diakhaby Demba Makalou Samba Niang Diatou Dia-Gueye Amadou Diop Dia Ibrahima Louis Martin Dieng Seynabou Lô nd.ye Méry Dia-Badiane Health Sciences Training and Research Unit Gaston Berger University Saint-Louis Senegal Department of Medicine Saint-Louis Regional Hospital Saint-Louis Senegal Infectious and Tropical Diseases Clinic of Fann Dakar Senegal

Introduction: COVID-19 is a global public health emergency that can cause acute respiratory distress syndrome. In countries where tuberculosis (TB) is endemic, coinfection of COVID-19 and TB is often encountered, which increases the risk of developing severe forms of COVID-19. Objectives: The aim of this study was to determine the prevalence of COVID-19/TB coinfection at the Epidemic treatment center (ETC) in Saint-Louis (Senegal) and to describe the epidemiological, clinical, paraclinical, and outcome profile of co-infected patients. Patients and Methods: This is a retrospective, cross-sectional, descriptive cohort study based on the records of COVID-19/ TB co-infected patients who were hospitalized at the ETC in Saint-Louis (Senegal) over an 18-month period from March 2020 to September 2021. Results: Out of a total of 454 hospitalizations, we collected records of 9 patients co-infected with COVID-19/TB, resulting in a prevalence of 2%. The study included patients with a median age of 34 years (range: 10-86 years), with a male predominance (7 cases) and a sex ratio of 3.5. The majority of patients (88.9%) had severe forms of COVID-19. Dyspnea and cough were reported in all patients (100%). Pulmonary TB was the most frequent localization, with 9 cases. The diagnosis of COVID-19 was confirmed by nasopharyngeal PCR in all patients (100%). Bacilloscopy was positive in 3 out of 5 cases. One patient tested positive for GeneXpert? MTB/RIF without rifampicin resistance. All patients were prescribed the hydroxychloroquine-azithromycin combination and anti-tuberculosis treatment. Out of the nine patients, four recovered (44.4%) and five died (55.5%). Conclusion: COVID-19/TB coinfection had a low prevalence in our cohort, but was associated with a high mortality due to the frequent occurrence of severe forms of the disease.

关键词： COVID-19 Tuberculosis Saint-Louis Senegal

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Profile of SARS-CoV-2 Infected Patients Hospitalized at the Epidemic Treatment Center (ETC) in Saint-Louis, Senegal during the First Two Waves

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Advances in Infectious Diseases 2024年第2期14卷 322-337页

作者： Alassane Dièye Papa Latyr Junior Diouf Bourama Diémé Moustapha Diedhiou Diatou Dia-Gueye Amadou Diop Dia Samba Niang Ibrahima Louis Martin Dieng Ameth Dieng Seynabou Lô nd.ye Méry Dia-Badiane Health Sciences Training and Research Unit Gaston Berger University Saint-Louis Senegal Emergency Department of Regional Hospital Center Saint-Louis Senegal Department of Infectious and Tropical Diseases of Fann Dakar Senegal

Introduction: The SARS-CoV-2 infection is a major public health emergency. Several risk factors are involved in the occurrence of respiratory distress that can lead to death despite resuscitation measures. Objectives: The aim of this study was to describe the epidemiological, clinical, paraclinical, therapeutic, and evolution profile of patients infected with SARS-CoV-2 hospitalized at the CTE of Saint-Louis (Senegal) during the first two waves. Patients and Methods: We conducted a retrospective, cross-sectional, descriptive, and analytical study that included all patients hospitalized at the ETC of Saint-Louis (Senegal) with SARS-CoV-2 infection from March 2020 to April 2021. Results: A total of 358 cases were collected, 256 (71.5%) during the first wave and 102 (28.5%) during the second wave. The mean age was 49.5 years (19.5). There was a male predominance (58.4%), with a sex ratio of 1.4. Hypertension was the main comorbidity, with 87 cases (24.3%). The most common functional signs were cough in 194 cases (54.2%), dyspnea in 143 cases (40%) and ageusia in 134 cases (37.4%). Thoracic CT scans were performed on 20 patients (5.6%), with severe involvement (50% - 75%) observed in 50% of cases. Hydroxychloroquine-azithromycin was prescribed to 351 patients (98%). Overall, 338 (94.4%) recovered and 17 (4.7%) died. In multivariate analysis, factors associated with death were male sex [OR = 2.645;95% CI: 1.530 - 4.785;p = 0.011], age 60 years [OR = 1.039;95% CI: 0.564 - 1.914;p = 0.002], the presence of comorbidities [OR = 2.171;95% CI: 0.564 - 3.429;p = 0.033], SpO2 (ambient air) 95% [OR = 2.061;95% CI: 0.616 - 3.827;p = 0.03], acute respiratory distress syndrome (ARDS) [OR = 0.635;95% CI: 0.316 - 1.275;p = 0.001], severe form [OR = 1.664;95% CI: 0.298 - 2.478;p = 0.016], occurrence of complications [OR = 0.521;95% CI: 0.287 - 0.944;p = 0.032], high creatinine levels [OR = 2.061;95% CI: 1.616 - 3.827;p = 0.026], and lymphopenia [OR = 0.485;95% CI: 0.370 - 0.636;p = 0.0

关键词： SARS-CoV-2 Saint-Louis Senegal

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