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Safety and efficacy of modified endoscopic ultrasound-guided selective N-butyl-2-cyanoacrylate injections for gastric variceal hemorrhage in left-sided portal hypertension
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作者 yan zeng Jian yang Jun-Wen Zhang 《World Journal of Gastrointestinal Endoscopy》 2024年第1期29-36,共8页
BACKGROUND Gastric variceal hemorrhage is one of the primary manifestations of left-sided portal hypertension(LSPH).The hemorrhage is fatal and requires safe and effective interventions.AIM To evaluate the clinical sa... BACKGROUND Gastric variceal hemorrhage is one of the primary manifestations of left-sided portal hypertension(LSPH).The hemorrhage is fatal and requires safe and effective interventions.AIM To evaluate the clinical safety and efficacy of modified endoscopic ultrasound(EUS)-guided selective N-butyl-2-cyanoacrylate(NBC)injections for gastric variceal hemorrhage in LSPH.METHODS A retrospective observational study of patients with LSPH-induced gastric variceal hemorrhage was conducted.Preoperative EUS evaluations were performed.Enrolled patients were divided into modified and conventional groups according to the NBC injection technique.The final selection of NBC injection technique depended on the patients’preferences and clinical status.The technical and clinical success rates,operation time,NBC doses,perioperative complications,postoperative hospital stay,and recurrent bleeding rates were analyzed,respectively.RESULTS A total of 27 patients were enrolled.No statistically significant differences were observed between the two groups regarding baseline characteristics.In comparison to patients in the conventional group,patients in the modified group demonstrated significantly reduced NBC doses(2.0±0.6 mL vs 3.1±1.0 mL;P=0.004)and increased endoscopic operation time(71.9±11.9 min vs 22.5±6.7 min;P<0.001).Meanwhile,the two groups had no significant difference in the technical and clinical success rates,perioperative complications,postoperative hospital stay,and recurrent bleeding rates.CONCLUSION Modified EUS-guided selective NBC injections demonstrated safety and efficacy for LSPH-induced gastric variceal hemorrhage,with advantages of reduced injection dose and no radiation risk.Drawbacks were time consumption and technical challenge. 展开更多
关键词 Endoscopic ultrasound SELECTIVE N-butyl-2-cyanoacrylate Gastric varices Hemorrhage Left-sided portal hypertension
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黄土丘陵沟壑区坡沟系统产流产沙对源-汇-路径格局的响应
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作者 严增 焦菊英 +11 位作者 唐柄哲 曹斌挺 李航 梁越 祁泓锟 廖俊 徐倩 严晰芹 李萌萌 姜晓晗 张子琦 李建军 《农业工程学报》 EI CAS CSCD 北大核心 2024年第5期118-127,共10页
坡沟系统是流域水土流失与治理的基本单元,掌握其产流产沙规律是有效解决水土流失区生态环境恢复重建的核心问题之一。该研究利用无人机遥感与地理信息系统技术对流域的土地利用进行识别,再确定5个不同坡沟系统(2个无人为干扰的退耕植... 坡沟系统是流域水土流失与治理的基本单元,掌握其产流产沙规律是有效解决水土流失区生态环境恢复重建的核心问题之一。该研究利用无人机遥感与地理信息系统技术对流域的土地利用进行识别,再确定5个不同坡沟系统(2个无人为干扰的退耕植被恢复+自然植被坡沟系统SG1和SG2、2个人为扰动的退耕植被恢复+自然植被坡沟系统SG3和SG4、1个果园+坡耕地的坡沟系统SG5)内泥沙源、汇及其输移路径分布特征,并在量化指标的基础上,结合2016—2022年坊塌小流域5个坡沟系统的降雨和产流产沙的监测数据,研究了不同坡沟系统的产流产沙特征及其对源-汇-路径格局的响应。结果表明:次降雨条件下,SG1和SG2的产沙模数显著低于其他坡沟系统(P<0.05),且SG3径流深和产沙模数均较大;SG2的年平均径流深显著低于SG5(P<0.05)。坡沟系统径流深分别与总坡沟系统、沟间地、沟谷地的泥沙源和汇最大斑块面积比显著正相关(P<0.05),且与沟间地泥沙源、汇指数的相关系数均要大于沟谷地,径流深与总坡沟系统路径的分岔比、沟间地与沟谷地的路径比降均呈现出显著负相关(P<0.05);产沙模数与各源汇指数之间均无显著的相关性,但与路径数量密度、长度密度、沟间地的路径分岔比呈显著正相关(P<0.05);径流深和产沙模数均与路径复杂度呈显著负相关(P<0.05)。可见,降低源/汇比例大小,适当增加泥沙输移路径的复杂度和输移距离,可有效减少坡沟系统的水土流失。研究可为坡沟系统土壤侵蚀防控以及流域生态保护和修复提供科学支撑。 展开更多
关键词 泥沙 景观 径流 坡沟系统 产流产沙 源汇 输移路径
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RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀的模拟效果分析
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作者 廖俊 焦菊英 +2 位作者 严增 李建军 张世杰 《水土保持学报》 CSCD 北大核心 2024年第2期97-108,共12页
[目的]为了探究RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀模拟的效果。[方法]基于陕北安塞区坊塌小流域内10个径流小区2016-2022年的降雨产流产沙监测资料,通过RUSLE模型中各因子在黄土高原的不同常用算法之间的变换组合,模拟144种... [目的]为了探究RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀模拟的效果。[方法]基于陕北安塞区坊塌小流域内10个径流小区2016-2022年的降雨产流产沙监测资料,通过RUSLE模型中各因子在黄土高原的不同常用算法之间的变换组合,模拟144种因子组合下各退耕植被恢复坡面的土壤侵蚀量,采用纳什效率系数(NSE)和均方根误差(RMSE)评价模型模拟结果的有效性。[结果]利用RUSLE模型144种因子组合模拟的退耕植被恢复坡面土壤侵蚀量,NSE范围为-38.47~0.19,RMSE范围为1.92~12.65 t/(hm 2·a),模拟效果较差,所选各因子算法难以适应退耕植被恢复坡面上的土壤流失量的评估,还需要对RUSLE模型各因子进一步改进。运用RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀模拟时,建议尽可能采用时间分辨率高的数据减小对R因子的计算误差,综合考虑土壤有机质含量、土壤粒径与团粒结构组成和容重等土壤理化性质对K因子的影响,以及植被覆盖度、植被高度、枯落物、生物结皮等对C因子的影响,充分考虑10°以上的坡度,细化其LS因子的算法。[结论]RUSLE模型无法很好地适用于黄土高原退耕植被恢复坡面土壤侵蚀的模拟。研究结果为土壤侵蚀模型的研发及RUSLE模型在黄土高原植被恢复坡面的应用提供一定参考依据。 展开更多
关键词 RUSLE模型 土壤侵蚀 退耕坡面 植被恢复 径流小区 黄土高原
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Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior
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作者 Man Han Deyang zeng +7 位作者 Wei Tan Xingxing Chen Shuyuan Bai Qiong Wu Yushan Chen Zhen Wei Yufei Mei yan zeng 《Neural Regeneration Research》 SCIE CAS 2025年第1期159-173,共15页
Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice ... Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and hippocampus.Determining how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress psychopathology.In this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of depression.We focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine circuit.We determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic system.Therefore,BDNF might be a biological indicator regulating stress-related processes in various brain regions. 展开更多
关键词 AMYGDALA chronic mild stress chronic social defeat stress corticolimbic system DEPRESSION HIPPOCAMPUS medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area
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Mutual feedback between algal blooming and global warming
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作者 Jianrong MA Guijun yanG +6 位作者 Xianfu ZHAO Boqiang QIN Kun SHAN Botian ZHOU yan zeng Jingfu WANG Jingan CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期787-801,共15页
Global warming and algal blooms have been two of the most pressing problems faced by the world today.In recent decades,numerous studies indicated that global warming promoted the expansion of algal blooms.However,rese... Global warming and algal blooms have been two of the most pressing problems faced by the world today.In recent decades,numerous studies indicated that global warming promoted the expansion of algal blooms.However,research on how algal blooms respond to global warming is scant.Global warming coupled with eutrophication promoted the rapid growth of phytoplankton,which resulted in an expansion of algal blooms.Algal blooms are affected by the combined effects of global warming,including increases in temperatures,CO_(2)concentration,and nutrient input to aquatic systems by extreme weather events.Since the growth of phytoplankton requires CO_(2),they appear to act as a carbon sink.Unfortunately,algal blooms will release CH4,CO_(2),and inorganic nitrogen when they die and decompose.As substrate nitrogen increases from decompose algal biomass,more N2O will be released by nitrification and denitrification.In comparison to CO_(2),CH4has 28-fold and N2O has 265-fold greenhouse effect.Moreover,algal blooms in the polar regions may contribute to melting glaciers and sea ice(will release greenhouse gas,which contribute to global warming)by reducing surface albedo,which consequently would accelerate global warming.Thus,algal blooms and global warming could form feedback loops which prevent human survival and development.Future researches shall examine the mechanism,trend,strength,and control strategies involved in this mutual feedback.Additionally,it will promote global projects of environmental protection combining governance greenhouse gas emissions and algal blooms,to form a geoengineering for regulating the cycles of carbon,nitrogen,and phosphorus. 展开更多
关键词 climate change carbon neutrality EUTROPHICATION greenhouse gas glaciers melting GEOENGINEERING
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Early gastric cancer recurrence after endoscopic submucosal dissection:Not to be ignored!
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作者 yan zeng Jian yang Jun-Wen Zhang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期8-12,共5页
This editorial comments on the article“Efficacy of multi-slice spiral computed tomography in evaluating gastric cancer recurrence after endoscopic submucosal dissection”.We focus on the importance of paying more att... This editorial comments on the article“Efficacy of multi-slice spiral computed tomography in evaluating gastric cancer recurrence after endoscopic submucosal dissection”.We focus on the importance of paying more attention to postendoscopic submucosal dissection(ESD)gastric cancer recurrence in patients with early gastric cancer(EGC)and how to manage it effectively.ESD has been a wellknown treatment and the mainstay for EGC,with the advantages of less invasion and fewer complications when compared with traditional surgical procedures.Despite a lower local recurrence rate after ESD,the problem of postoperative recurrence in patients with EGC has become increasingly non-ignorable with the global popularization of ESD technology and the increasing number of post-ESD patients. 展开更多
关键词 Early gastric cancer RECURRENCE Endoscopic submucosal dissection POSTOPERATIVE PREDICTION
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城市空间政治研究20年 被引量:4
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作者 段哲哲 王天凤 曾言 《公共行政评论》 北大核心 2023年第2期174-195,200,共23页
20世纪70年代,西方社会科学研究开始“空间转向”,城市空间政治议题逐步成为理论与实务热点之一。国外学者对城市空间政治研究的视角、方法与路径对本土城市空间理论与治理实践有重要的参考和借鉴意义。论文对国际主流城市研究与政治学... 20世纪70年代,西方社会科学研究开始“空间转向”,城市空间政治议题逐步成为理论与实务热点之一。国外学者对城市空间政治研究的视角、方法与路径对本土城市空间理论与治理实践有重要的参考和借鉴意义。论文对国际主流城市研究与政治学研究期刊文献梳理分析发现:(1)20年来国际主流期刊研究议题由北方城市向南方城市转移,研究主题由宏观向中观微观转向。(2)研究方法从案例研究逐步转向以量化为主的多元化方法,大数据、GPS、实验方法等前沿方法开始应用在研究中。(3)城市空间政治研究发展遭遇三大瓶颈,即对“新自由主义”批判鸿沟、“向南”鸿沟与“学术热潮”鸿沟。城市空间政治研究的发展前景取决于如何建构新的解释南方城市发展与治理的理论,进而确定本领域学科定位。西方城市空间政治议题研究可为我国城市治理提供一定程度的借鉴。在宏观层面上,需提升多主体协同参与城市治理的积极性;在中观层面上,需在社区空间层面促进效率价值与公平价值的平衡;在微观层面上,需保障城市新老居民的空间权利与实现内部融合。 展开更多
关键词 城市 空间政治 SSCI期刊 文献计量
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Modified endoscopic ultrasound-guided selective N-butyl-2-cyanoacrylate injections for gastric variceal hemorrhage in left-sided portal hypertension:A case report 被引量:2
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作者 Jian yang yan zeng Jun-Wen Zhang 《World Journal of Clinical Cases》 SCIE 2022年第18期6254-6260,共7页
BACKGROUND Left-sided portal hypertension(LSPH),also known as sinistral portal hypertension or regional portal hypertension,refers to extrahepatic portal hypertension caused by splenic vein obstruction or stenosis.N-b... BACKGROUND Left-sided portal hypertension(LSPH),also known as sinistral portal hypertension or regional portal hypertension,refers to extrahepatic portal hypertension caused by splenic vein obstruction or stenosis.N-butyl-2-cyanoacrylate(NBC)has been widely used in the endoscopic hemostasis of portal hypertension,but adverse events including renal or pulmonary thromboembolism,mucosal necrosis and gastrointestinal(GI)bleeding may occur after treatment.Herein,we report successfully managing gastric variceal(GV)hemorrhage secondary to LSPH using modified endoscopic ultrasound(EUS)-guided selective NBC injections.CASE SUMMARY A 35-year-old man was referred to our hospital due to an upper GI hemorrhage.Gastroscopy revealed GV hemorrhage and computed tomography venography(CTV)confirmed LSPH.The patient requested endoscopic procedures and rejected surgical therapies including splenectomy.EUS-guided selective NBC injections were performed and confluences of gastric varices were selected as the injection sites to reduce the injection dose.The“sandwich”method using undiluted NBC and hypertonic glucose was applied.No complications occurred.The patient was followed up regularly after discharge.Three months later,the follow-up gastroscopy revealed firm gastric submucosa with no sign of NBC expulsion and the follow-up CTV showed improvements in LSPH.No recurrent GI hemorrhage was reported during this follow-up period.CONCLUSION EUS-guided selective NBC injection may represent an effective and economical treatment for GV hemorrhage in patients with LSPH. 展开更多
关键词 Left-sided portal hypertension Endoscopic ultrasound SELECTIVE N-butyl-2-cyanoacrylate Gastric varices Case report
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生长调节物质对林木花芽分化的影响
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作者 张江涛 杨淑红 +2 位作者 晏增 赵蓬晖 马永涛 《温带林业研究》 2023年第2期67-72,共6页
花芽分化是林木枝条上的生长点由营养生长向生殖生长转化的生理和形态标志,是林木开花结实的重要阶段之一。由于营养生长和生殖生长是相互促进又相互制约的,并在一定范围内有相对比例可以互相转换,花芽分化过程又是内外因素共同作用、... 花芽分化是林木枝条上的生长点由营养生长向生殖生长转化的生理和形态标志,是林木开花结实的重要阶段之一。由于营养生长和生殖生长是相互促进又相互制约的,并在一定范围内有相对比例可以互相转换,花芽分化过程又是内外因素共同作用、相互协调的结果,因此其状况直接影响着林木结实的质量与数量。在林木生产实践中常根据市场需求采用技术方法和措施,调控林木花芽分化进程,从而实现定向培育。本文综述了影响林木花芽分化的主要因素和调控机制,归纳总结可能影响林木花芽分化的生产管理、调节剂应用及其他调控措施的研究进展与成果,并对林木花芽分化研究方向提出来了展望,以期为林木的定向培育提供参考。 展开更多
关键词 花芽分化 调节物质 影响因素 调控技术 定向培育
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镍纳米粒子耦合氧空位高效催化转化棕榈酸制备烷烃
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作者 曾严 王慧 +7 位作者 杨惠茹 隽超 李丹 温晓东 张帆 邹吉军 彭冲 胡常伟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第4期229-242,共14页
随着能源需求的增加和生态环境的恶化,可再生资源的开发与利用越来越受到人们的重视.其中,生物质能源分布广泛,储量丰富,是化石燃料的理想替代品.然而生物质具有高含氧量、高粘度和低热值等特性,开发高效的加氢脱氧催化剂对生物质资源... 随着能源需求的增加和生态环境的恶化,可再生资源的开发与利用越来越受到人们的重视.其中,生物质能源分布广泛,储量丰富,是化石燃料的理想替代品.然而生物质具有高含氧量、高粘度和低热值等特性,开发高效的加氢脱氧催化剂对生物质资源的开发和利用具有重要的应用价值.近年来,研究者们对生物质(脂肪酸及其衍生物)加氢脱氧催化体系进行了大量研究,发现Ni/CeO_(2)基催化剂能够有效地催化生物质转化并获得较高的生物油产率,然而CeO_(2)载体的氧空位含量与Ni纳米颗粒尺寸、催化剂脱氧性能之间的关系仍然不明晰.本文采用水热合成法和沉淀法分别制备了H-CeO_(2)和P-CeO_(2)载体(商用CeO_(2)标记为C-CeO_(2)),通过浸渍法制备了Ni/H-CeO_(2),Ni/P-CeO_(2)和Ni/C-CeO_(2)催化剂,同时采用无氧空位的SiO_(2)做载体制备了Ni/SiO_(2)催化剂,研究了CeO_(2)氧空位含量对Ni纳米粒子尺寸的影响及其与加氢脱氧催化性能之间的关系.EPR结果表明,不同载体上氧空位含量的顺序为H-CeO_(2)>P-CeO_(2)>C-CeO_(2).XRD结果表明,在H-CeO_(2)载体上生成的Ni纳米粒子尺寸最小,分散度最高;在C-CeO_(2)载体上生成的Ni纳米粒子尺寸最大,分散度最差;而在无氧空位的SiO_(2)载体上生成的Ni纳米粒子尺寸明显大于H-CeO_(2)和P-CeO_(2)载体上生成的Ni纳米粒子.XPS结果显示,不同载体上的O表面/(O表面+O晶格)的比值顺序为H-CeO_(2)>P-CeO_(2)>C-CeO_(2),表明H-CeO_(2)载体上具有最高的氧空位含量,C-CeO_(2)载体上氧空位含量最低,与EPR结果一致;Ni/H-CeO_(2),Ni/P-CeO_(2)和Ni/C-CeO_(2)催化剂上氧空位含量顺序与载体一致,但其氧空位含量比纯载体高,说明Ni有利于氧空位的生成.Raman结果表明,Ni/H-CeO_(2)催化剂上具有的氧空位含量最高,Ni/P-CeO_(2)次之,Ni/C-CeO_(2)最差,与XPS结果一致.H2-TPR结果表明,氧空位的存在增强了Ni与CeO_(2)载体的相互作用,有利于Ni的分散.SEM和TEM实验结果也表明了在氧空位含量最高的H-CeO_(2)载体上Ni分散度最高.DFT结果进一步证实了高的氧空位含量增强了金属-载体相互作用,促进了Ni的分散.电荷分析表明,Ni纳米颗粒和CeO_(2)载体之间存在电子转移,在具有丰富氧空位的表面上从Ni转移到CeO_(2)的电子数少于规则表面的电子数,Ni原子将电子转移到载体上,降低了Ni原子的氧化程度.活性结果表明,三种纯载体催化转化棕榈酸的效果均不佳,烷烃选择性均低于5.0%;负载活性组分Ni后,催化性能明显提升.在Ni/C-CeO_(2)催化剂上,棕榈酸的转化率为72.1%,十五烷的选择性为21.9%;Ni/P-CeO_(2)催化剂对棕榈酸的转化率达到99.6%,十五烷的选择性为77.6%;Ni/H-CeO_(2)催化剂具有最佳的催化活性,其催化性能高于大部分文献报道的贵金属催化剂,棕榈酸转化率为100%,十五烷选择性达到94.8%;而在无氧空位的Ni/SiO_(2)催化剂上性能最差,棕榈酸转化率仅为52.9%,得到少量十五烷,也未检测到十六烷,这表明丰富的氧空位在棕榈酸转化过程中发挥了重要作用.结合文献及活性结果分析,丰富的氧空位有利于吸附更多的棕榈酸,从而有利于其转化.通过反应后的XRD及TG测试结果发现,Ni纳米颗粒的尺寸在反应后没有显著变化,表明氧空位也能有效地稳定Ni纳米颗粒尺寸.不同尺寸Ni纳米颗粒的催化剂活性结果表明,在较小尺寸的Ni纳米颗粒催化剂上可以获得更高的十五烷选择性,表明十五烷选择性与Ni纳米颗粒尺寸相关联.综上,Ni/H-CeO_(2)的优异催化性能归因于高氧空位含量和小尺寸Ni纳米颗粒的协同耦合作用. 展开更多
关键词 加氢脱氧 氧空位 Ni纳米粒子 棕榈酸转化 生物燃料
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Correlation between serum lipid profiles and cognitive impairment in old age:a cross-sectional study 被引量:3
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作者 Yafu Yu Pingting yan +7 位作者 Guirong Cheng Dan Liu Lang Xu Mengliu yang Heng Xu Xi Cheng Pengfei Lian yan zeng 《General Psychiatry》 CSCD 2023年第2期129-137,共9页
Background The correlation between cognitive function and lipid profiles,including total cholesterol,low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C)and triglycerides,is inconsist... Background The correlation between cognitive function and lipid profiles,including total cholesterol,low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C)and triglycerides,is inconsistent.Aims This cross-sectional study investigated the association between serum lipid levels and the prevalence of cognitive impairment among community-dwelling older adults and explored this difference in association by gender and urban-rural residency.Methods Participants aged 65 and above in urban and rural areas were recruited between 2018 and 2020,selected from the Hubei Memory and Aging Cohort Study.Detailed neuropsychological evaluations,clinical examinations and laboratory tests were conducted in community health service centres.Multivariate logistic regression was used to analyse the correlation between serum lipid profiles and the prevalence of cognitive impairment.Results We identified 1336 cognitively impaired adults(≥65 years)-1066 with mild cognitive impairment and 270 with dementia-from 4746 participants.Triglycerides level was correlated with cognitive impairment in the total sample(χ2=6.420,p=0.011).In gender-stratified multivariate analysis,high triglycerides in males reduced the risk of cognitive impairment(OR:0.785,95%CI:0.623 to 0.989,p=0.040),and high LDL-C in females increased the risk of cognitive impairment(OR:1.282,95%CI:1.040 to 1.581,p=0.020).In both gender-stratified and urban-rural stratified multivariate analyses,high triglycerides reduced the risk of cognitive impairment in older urban men(OR:0.734,95%CI:0.551 to 0.977,p=0.034),and high LDL-C increased the risk of cognitive impairment in older rural women(OR:1.830,95%CI:1.119 to 2.991,p=0.016).Conclusions There are gender and urban-rural differences in the correlation of serum lipids with cognitive impairment.High triglycerides levels may be a protective factor for cognitive function in older urban men,while high LDL-C levels may be a risk factor for cognitive function in older rural women. 展开更多
关键词 IMPAIRMENT IMPAIRED protective
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Oxygen vacancy defects engineering on Cu-doped Co_(3)O_(4) for promoting effective COS hydrolysis 被引量:2
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作者 Guanyu Mu yan zeng +5 位作者 Yong Zheng yanning Cao Fujian Liu Shijing Liang Yingying Zhan Lilong Jiang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期831-841,共11页
The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of... The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of the catalysts.In situ DRIFTS and XPS spectra reveal that COS and H_(2)O are adsorbed and activated by oxygen vacancy.The 10 at%Cu doped Co_(3)O_(4) sample(10Cu-Co_(3)O_(4))exhibits the optimal activity,100%of COS conversion at 70℃.The improved oxygen vacancies of CueCo_(3)O_(4) accelerate the activation of H_(2)O to form active -OH.COS binds with hydroxyl to form the intermediate HSCO^(-)_(2),and then the activated-OH on the oxygen vacancy reacts with HSCO^(-)_(2) to form HCO^(-)_(3).Meanwhile,the catalyst exhibits high catalytic stability because copper species(Cu+/Cu^(2+))redox cycle mitigate the sulfation of Co_(3)O_(4)(Co^(2+)/Co^(3+)).Our work offers a promising approach for the rational design of cobalt-related catalysts in the highly efficient hydrolysis COS process. 展开更多
关键词 Oxygen vacancy COS hydrolysis In situ spectra Cu doped Co_(3)O_(4)
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A 1.1 Mb duplication CNV on chromosome 17 contributes to skeletal muscle development in Boer goats 被引量:1
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作者 Ying Yuan Wei-Yi Zhang +28 位作者 Bai-Gao yang Dong-Ke Zhou Lu Xu Yong-Meng He Hao-Yuan Zhang Cheng-Li Liu Yue-Hui Ma Ming-Xing Chu Wen-Guang Zhang Hui-Jiang Gao Lin Jiang Fu-Ping Zhao Lu-Pei Zhang Ri-Su Na Baatarchogt Oyungerel yan-Guo Han yan zeng Shi-Zhi Wang Huai-Zhi Jiang Hong-Ping Zhang Xun-Ping Jiang Jian-Ning He Hao Liang Kaushalendra Kaushalendra Ya-Wang Sun Yong-Fu Huang Yong-Ju Zhao Zhong-Quan Zhao Guang-Xin E 《Zoological Research》 SCIE CAS CSCD 2023年第2期303-314,共12页
The Boer goat is one of the top meat breeds in modern animal husbandry and has attracted widespread attention for its unique growth performance.However,the genetic basis of muscle development in the Boer goat remains ... The Boer goat is one of the top meat breeds in modern animal husbandry and has attracted widespread attention for its unique growth performance.However,the genetic basis of muscle development in the Boer goat remains obscure.In this study,we identified specific structural variants in the Boer goat based on genome-wide selection signals and analyzed the basis of the molecular heredity of related candidate genes in muscle development.A total of9 959 autosomal copy number variations(CNVs) were identified through selection signal analysis in 127 goat genomes.Specifically,we confirmed that the highest signal CNV(HSV) was a chromosomal arrangement containing an approximately 1.11 Mb(CHIR17:60062304-61171840 bp) duplicated fragment inserted in reverse orientation and a 5 362 bp deleted region(CHIR17:60145940-60151302 bp) with overlapping genes(e.g.,ARHGAP10,NR3C2,EDNRA,PRMT9,and TMEM184C).The homozygous duplicated HSV genotype(+/+) was found in 96% of Boer goats but was not detected in Eurasian goats and was only detected in 4% of indigenous African goats.The expression network of three candidate genes(ARHGAP10,NR3C2,and EDNRA)regulating dose transcription was constructed by RNA sequencing.Results indicated that these genes were involved in the proliferation and differentiation of skeletal muscle satellite cells(SMSCs) and their overexpression significantly increased the expression of SAA3.The HSV of the Boer goat contributed to superior skeletal muscle growth via the dose effects of overlapping genes. 展开更多
关键词 Boer goat CNV Muscle development SMSCs
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Endoscopic transluminal drainage and necrosectomy for infected necrotizing pancreatitis:Progress and challenges 被引量:1
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作者 yan zeng Jian yang Jun-Wen Zhang 《World Journal of Clinical Cases》 SCIE 2023年第9期1888-1902,共15页
Infected necrotizing pancreatitis(INP)represents a severe condition in patients with acute pancreatitis.Invasive interventions are recommended in symptomatic INP.Growing evidence has suggested interventional strategie... Infected necrotizing pancreatitis(INP)represents a severe condition in patients with acute pancreatitis.Invasive interventions are recommended in symptomatic INP.Growing evidence has suggested interventional strategies of INP evolving from traditional surgery to minimally invasive step-up endoscopic procedures.However,there is still no standardized protocol for endoscopic interventions.Recently,various studies have been published about the endoscopic management of INP.This article reviews published articles and guidelines to present the progress and challenges of endoscopic transluminal drainage and necrosectomy in INP. 展开更多
关键词 ENDOSCOPIC Drainage NECROSECTOMY Infected necrotizing pancreatitis PROGRESS CHALLENGE
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Mediating effect of mindfulness level on the relationship between marital quality and postpartum depression among primiparas
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作者 Jian yang Xin-Zhu Lin +4 位作者 Qian-Wen Guo Cheng-Ling Wang Ren-yan yang Jun-Wen Zhang yan zeng 《World Journal of Clinical Cases》 SCIE 2023年第12期2729-2739,共11页
BACKGROUND Postpartum depression refers to a depressive episode or depressive symptoms up to 12 mo after delivery.Trait mindfulness has presented a protective factor for postpartum depressive symptoms and proved effic... BACKGROUND Postpartum depression refers to a depressive episode or depressive symptoms up to 12 mo after delivery.Trait mindfulness has presented a protective factor for postpartum depressive symptoms and proved efficient in improving relationship satisfaction among couples.AIM To investigate the correlations among mindfulness,marital quality,anxiety,and depression in a large city in western China during the post-corona virus infectious disease-2019 era and determine whether trait mindfulness mediates the relationship between marital quality and postpartum anxiety and depression among primiparas.METHODS A cross-sectional study was conducted.The self-administered questionnaire was submitted online through smartphones.The levels of mindfulness,anxiety,depression,and marital quality were respectively investigated by the mindful attention awareness scale(MAAS),the self-rating anxiety scale(SAS),the selfrating depression scale(SDS),and the marriage perception scale(MPS)in these enrolled Han and Tujia primiparas.RESULTS No statistical significance was observed in the prevalence of postpartum anxiety and depression,nor scores of MAAS and MPS-Total in different regions or ethnicities(P>0.05).However,MPSMarital interaction(P<0.05),MPS-Family relationship(MPS-FR)(P<0.01),and MPS-Marital conflict(MPS-MC)(P<0.01)scores of urban primiparas were higher than those of rural primiparas.The MPS-MC score of Han primiparas was higher than that of Tujia primiparas(P<0.05).Negative correlations were observed between MAAS and SAS(r=-0.457,P<0.01),and MAAS and SDS(r=-0.439,P<0.01).SAS has revealed a highly positive correlation with SDS(r=0.720,P<0.01)and a weak negative correlation with MPS(r=-0.200,P<0.05).Besides,a weak negative correlation was observed between MAAS and MPS-MC(r=-0.184,P<0.05),and a weak positive correlation was noticed between SAS and MPS-MC(r=-0.225,P<0.01).Mediation analysis demonstrated a full mediation effect of mindfulness level on the relationship between MPS-FR and postpartum anxiety(P<0.05,95%CI:-0.384 to 0.033),MPS-MC and postpartum anxiety(P<0.01,95%CI:0.027-0.193),MPS-FR and postpartum depression(P<0.05,95%CI:-0.365 to 0.031),and MPS-MC and postpartum depression(P<0.01,95%CI:0.022-0.206).CONCLUSION Mindfulness demonstrates negative correlations with marital conflict,postpartum anxiety and depression,and it may have cross-ethnic and trans-regional characteristics.Although the mindfulness levels have revealed no significant mediating effect between the total score of marital quality and postpartum depression in this study,it demonstrates a full mediation effect on the relationships between family relationships,marital conflict,and postpartum anxiety and depression. 展开更多
关键词 Mediating effect MINDFULNESS Marital quality Postpartum depression Postpartum anxiety Primiparas
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Unraveling the influence of interface defects on antimony trisulfide solar cells
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作者 Hongyi Chen Cheng Wang +8 位作者 Shaoying Wang Ruiming Li yan zeng Zhe Li Zhengwei Ou Qianqian Lin Jianmin Li Ti Wang Hongxing Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第3期262-267,I0008,共7页
Antimony trisulfide(Sb_(2)S_(3)) solar cells suffer from large open circuit voltage deficits due to their intrinsic defects which limit the power conversion efficiency.Thus,it is important to elucidate these defects’... Antimony trisulfide(Sb_(2)S_(3)) solar cells suffer from large open circuit voltage deficits due to their intrinsic defects which limit the power conversion efficiency.Thus,it is important to elucidate these defects’ origin and defects at the interface.Here,we discover that sulfide radical defects have a significant impact on the performance of Sb_(2)S_(3)solar cells.Moreover,it has been illustrated that these defects at the CdS/Sb_(2)S_(3)interface can be reduced by optimizing the deposition process.A trap distribution model is used to quantify the defect density at the CdS/Sb_(2)S_(3)interface.It shows that the interface defects can be reduced by24% by improving the deposition process.This work reveals the importance of interface defects and guides the future optimization of Sb_(2)S_(3)solar cells. 展开更多
关键词 Antimony trisulfide Interface defect Transient absorption spectroscopy
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A Client Selection Method Based on Loss Function Optimization for Federated Learning
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作者 yan zeng Siyuan Teng +4 位作者 Tian Xiang Jilin Zhang Yuankai Mu Yongjian Ren Jian Wan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期1047-1064,共18页
Federated learning is a distributedmachine learningmethod that can solve the increasingly serious problemof data islands and user data privacy,as it allows training data to be kept locally and not shared with other us... Federated learning is a distributedmachine learningmethod that can solve the increasingly serious problemof data islands and user data privacy,as it allows training data to be kept locally and not shared with other users.It trains a globalmodel by aggregating locally-computedmodels of clients rather than their rawdata.However,the divergence of local models caused by data heterogeneity of different clients may lead to slow convergence of the global model.For this problem,we focus on the client selection with federated learning,which can affect the convergence performance of the global model with the selected local models.We propose FedChoice,a client selection method based on loss function optimization,to select appropriate local models to improve the convergence of the global model.It firstly sets selected probability for clients with the value of loss function,and the client with high loss will be set higher selected probability,which can make them more likely to participate in training.Then,it introduces a local control vector and a global control vector to predict the local gradient direction and global gradient direction,respectively,and calculates the gradient correction vector to correct the gradient direction to reduce the cumulative deviationof the local gradient causedby theNon-IIDdata.Wemake experiments to verify the validity of FedChoice on CIFAR-10,CINIC-10,MNIST,EMNITS,and FEMNIST datasets,and the results show that the convergence of FedChoice is significantly improved,compared with FedAvg,FedProx,and FedNova. 展开更多
关键词 Federated learning model aggregation Non-IID
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Exploring the psychological impact of the 2022 SARS-CoV-2 Omicron variant outbreak in China
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作者 Gangbin Han Guirong Cheng +45 位作者 Feifei Hu Chunli Li Dan Liu Juan Zhou Jing Liu Linya Huang Xiaochang Liu Qianqian Nie Dan Song Deyang zeng Lang Xu Jinquan Li Yushan Chen Zhen Wei Qiong Wu Xiaoming He Qingming Wu Wei Tan Yufei Mei Xingxing Chen yangming Ou Jingjing ZhangYafu Yu Mengliu yang Pengfei Lian Fukai Zhou Renjia Fan Hong Wan Chenlu Hu Yidi Fu Shiyue Li Junyi Wang Cheng Cai Mengdie Pei Yuyang Cui Wanying Cai Yiqing Li Shiyao Pan Chang Chen yan He Zhaoxia Wu Liu Hu Liang Tao Hongyan Xiao Xinyan Xie yan zeng 《General Psychiatry》 CSCD 2023年第6期541-546,共6页
To the editor:The impact of the coronavirus disease 2019(COVID-19)pandemic in 2020 on mental health was substantialin Chinai2and various other countries.34 Beyond the direct consequences of COVID-19,the pandemic creat... To the editor:The impact of the coronavirus disease 2019(COVID-19)pandemic in 2020 on mental health was substantialin Chinai2and various other countries.34 Beyond the direct consequences of COVID-19,the pandemic created an environment in which many determinants of mental health were affected.Issues associated with the pandemic,such as loss of livelihood,limited access to medical services,reduced social interactions,and economic downturn,could potentially have adverse effects on the population's mental well-being.5 In November 2021,the World Health Organization(WHO)designated the new variant of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),variant B.1.1.529,as a variant of concern and named it Omicron;its rapid mutation and spread raised a new global health concern. 展开更多
关键词 ACUTE IMPACT consequences
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Distribution,exploitation,and utilization of intermediate-to-deep geothermal resources in eastern China
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作者 Zhiliang He Jianyun Feng +1 位作者 Jun Luo yan zeng 《Energy Geoscience》 2023年第4期25-45,共21页
The part of China,east of the Hu Huanyong Line,is commonly referred to as eastern China.It is characterized by a high population density and a well-developed economy;it also has huge energy demands.This study assesses... The part of China,east of the Hu Huanyong Line,is commonly referred to as eastern China.It is characterized by a high population density and a well-developed economy;it also has huge energy demands.This study assesses and promotes the large-scale development of geothermal resources in eastern China by analyzing deep geological structures,geothermal regimes,and typical geothermal systems.These analyses are based on data collected from geotectology,deep geophysics,geothermics,structural geology,and petrology.Determining the distribution patterns of intermediate-to-deep geothermal resources in the region helps develop prospects for their exploitation and utilization.Eastern China hosts superimposed layers of rocks from three major,global tectonic domainsd namely Paleo-Asian,Circum-Pacific,and Tethyan rocks.The structure of its crust and mantle exhibits a special flyover pattern,with basins and mountains as well as well-spaced uplifts and depressions alternatively on top.The lithosphere in Northeast China and North China is characterized by a thin,low density crust and mantle,whereas the lithosphere in South China has a thin,low density crust and a thick,high density mantle.The middle and upper crust contain geobodies with high conductivity and low velocity,with varying degrees of development that create favorable conditions for the formation and enrichment of geothermal resources.Moderate-to-high temperature geothermal resources are distributed in the MesozoiceCenozoic basins in eastern China,although moderate temperature geothermal resources with low abundance dominate.Porous sandstone reservoirs,karstified fractured-vuggy carbonate reservoirs,and fissured granite reservoirs are the main types of geothermal reservoirs in this region.Under the currently available technical conditions,the exploitation and utilization of geothermal resources in eastern China favor direct utilization over large-scale geothermal power generation.In Northeast China and North China,geothermal resources could be applied for large-scale geothermal heating purposes;geothermal heating could be applied during winter along parts of the Yangtze River while geothermal cooling would be more suitable for summer there;geothermal cooling could also be applied to much of South China.Geothermal resources can also be applied to high value-added industries,to aid agricultural practices,and for tourism. 展开更多
关键词 Intermediate-to-deep geothermal resources Distribution pattern Geothermal system Direct utilization of geothermal energy Mesozoicecenozoic sedimentary basin Eastern China
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Deep bedrock geothermal resources in the Maichen Sag,Beibuwan Basin and their potential for exploitation and utilization
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作者 yan zeng Ying Zhang 《Energy Geoscience》 2023年第4期188-197,共10页
The Maichen Sag in the south-central part of the Beibuwan Basin is abundant in geothermal resources that have not been widely exploited and utilized due to inadequate research on it.This study evaluated the geothermal... The Maichen Sag in the south-central part of the Beibuwan Basin is abundant in geothermal resources that have not been widely exploited and utilized due to inadequate research on it.This study evaluated the geothermal resources in the Maichen Sag based on the regional geological setting and geothermal conditions.Grid units for assessment and a geological model for areas with geothermal resources were established using spatial analysis techniques.The spatial distribution models of the physical and thermophysical properties of the geothermal reservoirs were also built using the Kriging interpolation method.Based on the terrestrial heat flow distribution in the target areas,the spatial distribution of the geo-temperature field through the inversion under the constraints of the temperature data from boreholes were predicted.Factors such as deep geo-temperature,thermophysical properties of rocks,and terrestrial heat flow values,were integrated into this quantitative evaluation of geothermal resources through the geological modeling-based volume method and the geothermal reservoir engineering-based numerical simulation method.The results show that the Maichen Sag has favorable heat source conditions with intersected,deep-rooted faults and widely developed Upper Paleozoic fissured granite geothermal reservoirs.The northern outer slope zone at a burial depth of 3‒5 km on the tectonic plane of the basement in the sag is suggested to be a potential target area,where,as calculated using the volume method,is likely to be the home to the total geothermal resources of 80.4×10^(9)GJ(i.e.,2.75×10^(9)tonnes of coal equivalent(tce))in the bedrock geothermal reservoirs at a burial depth of 3‒6 km.The geotemperature of 172‒201℃at a formation depth of 5 km in the sag also indicates that the deep geothermal resources are of high value for exploitation. 展开更多
关键词 Maichen sag Geothermal resource Resource evaluation Parameter estimation for geothermal resource exploitation Numerical simulation
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