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三级综合医院护士生物安全事件核心应急能力指标体系的构建 被引量:1
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作者 赵燕祥 肖芳林 +2 位作者 朱敏 支晨 马慧 《军事护理》 CSCD 北大核心 2024年第3期23-26,共4页
目的构建三级综合医院护士生物安全事件核心应急能力指标体系,为护士相关核心应急能力评价提供依据。方法通过文献研究、专家访谈构建指标体系初稿,纳入19名专家进行3轮专家函询,征询专家意见并修订,确定最终指标体系并设置指标权重。结... 目的构建三级综合医院护士生物安全事件核心应急能力指标体系,为护士相关核心应急能力评价提供依据。方法通过文献研究、专家访谈构建指标体系初稿,纳入19名专家进行3轮专家函询,征询专家意见并修订,确定最终指标体系并设置指标权重。结果3轮专家函询专家权威系数分别为0.893、0.896、0.903;协调系数分别为0.209~0.295、0.217~0.299、0.232~0.304(P<0.01),最终构建的三级综合医院护士生物安全事件核心应急能力指标体系包含4个一级指标、19个二级指标、66个三级指标。结论构建的指标体系具有权威性和科学性,结果合理实用,可用于评价护士生物安全事件核心应急能力。 展开更多
关键词 护士 生物安全 核心应急能力 评价指标
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Expert consensus on endodontic therapy for patients withsystemic conditions 被引量:1
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作者 Xin Xu Xin Zheng +21 位作者 Fei Lin Qing Yu Benxiang Hou zhi chen Xi Wei Lihong Qiu Wenxia chen Jiyao Li Lili chen Zuomin Wang Hongkun Wu zhiyue Lu Jizhi Zhao Yuhong Liang Jin Zhao Yihuai Pan Shuang Pan Xiaoyan Wang Deqin Yang Yanfang Ren Lin Yue Xuedong Zhou 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第3期390-397,共8页
The overall health condition of patients significantly affects the diagnosis, treatment, and prognosis of endodontic diseases. Asystemic consideration of the patient’s overall health along with oral conditions holds ... The overall health condition of patients significantly affects the diagnosis, treatment, and prognosis of endodontic diseases. Asystemic consideration of the patient’s overall health along with oral conditions holds the utmost importance in determining thenecessity and feasibility of endodontic therapy, as well as selecting appropriate therapeutic approaches. This expert consensus is acollaborative effort by specialists from endodontics and clinical physicians across the nation based on the current clinical evidence,aiming to provide general guidance on clinical procedures, improve patient safety and enhance clinical outcomes of endodontictherapy in patients with compromised overall health. 展开更多
关键词 PATIENTS DIAGNOSIS PROGNOSIS
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Expert consensus on difficulty assessment of endodontic therapy 被引量:1
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作者 Dingming Huang Xiaoyan Wang +33 位作者 Jingping Liang Junqi Ling Zhuan Bian Qing Yu Benxiang Hou Xinmei chen Jiyao Li Ling Ye Lei cheng Xin Xu Tao Hu Hongkun Wu Bin Guo Qin Su zhi chen Lihong Qiu Wenxia chen Xi Wei Zhengwei Huang Jinhua Yu Zhengmei Lin Qi Zhang Deqin Yang Jin Zhao Shuang Pan Jian Yang Jiayuan Wu Yihuai Pan Xiaoli Xie Shuli Deng Xiaojing Huang Lan Zhang Lin Yue Xuedong Zhou 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期15-25,共11页
Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is ... Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy(RCT). Recent research, encompassing bacterial etiology and advanced imaging techniques, contributes to our understanding of the root canal system’s anatomy intricacies and the technique sensitivity of RCT. Success in RCT hinges on factors like patients, infection severity, root canal anatomy, and treatment techniques. Therefore, improving disease management is a key issue to combat endodontic diseases and cure periapical lesions. The clinical difficulty assessment system of RCT is established based on patient conditions, tooth conditions, root canal configuration, and root canal needing retreatment, and emphasizes pre-treatment risk assessment for optimal outcomes. The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT. These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics. 展开更多
关键词 ANATOMY DIFFICULTY TREATMENT
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Characteristics and main controlling factors of helium resources in the main petroliferous basins of the North China Craton
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作者 Zihan Gao zhi chen +5 位作者 Hongyi He Zhaofei Liu Chang Lu Hanyu Wang Yili Luo Ying Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期23-33,共11页
At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of... At present, the main controlling factors of helium accumulation is one of the key scientific problems restricting the exploration and development of helium reservoir. In this paper, based on the calculation results of He generation rate and the geochemical characteristics of the produced gas, both the similarities and differences between natural gas and He resources in the Bohai Bay, Ordos and the surrounding Songliao Basin are compared and analyzed, discussing the main controlling factors of helium resources in the three main petroliferous basins of the North China Craton. It is found that the three basins of Bohai Bay, Ordos and Songliao have similar characteristics of source rocks, reservoirs and cap rocks, that's why their methane resource characteristics are essentially the same. The calculated ~4He generation per cubic metamorphic crystalline basement in the three basins is roughly equivalent, which is consistent with the measured He resources, and it is believed that the ~4He of radiogenic from the crust is the main factor controlling the overall He accumulation in the three basins;there is almost no contribution of the mantle-derived CH_4, which suggests that the transport and uplift of mantle-derived ~3He carried by the present-day magmatic activities along the deep-large faults is not the main reason for the mantle-derived ~3He mixing in the basins. Combined with the results of regional volcanic and geophysical studies,it is concluded that under the background of the destruction of North China Craton, magma intrusion carried a large amount of mantle-derived material and formed basic volcanic rocks in the Bohai Bay Basin and Songliao Basin, which replenished mantle-derived ~3He for the interior of the basins, and that strong seismic activities in and around the basins also promoted the upward migration of mantle source ~3He. This study suggests that the tectonic zone with dense volcanic rocks in the Cenozoic era and a high incidence of historical strong earthquakes history may be a potential area for helium resource exploration. 展开更多
关键词 HELIUM Bohai Bay Basin destruction of the North China Craton FAULT Cenozoic volcanic rocks strong earthquake activity
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Preparation and Analysis of Carbon Fiber-Silicon Carbide Thermally Conductive Asphalt Concrete
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作者 zhiyong Yang Enjie Hu +3 位作者 Lei Xi zhi chen Feng Xiong Chuanhai Zhan 《Fluid Dynamics & Materials Processing》 EI 2024年第4期705-723,共19页
An experimental investigation into the thermal conductivity of CF-SiC two-phase composite asphalt concrete is presented.The main objective of this study was to verify the possibility of using SiC powder instead of min... An experimental investigation into the thermal conductivity of CF-SiC two-phase composite asphalt concrete is presented.The main objective of this study was to verify the possibility of using SiC powder instead of mineral powder as the thermal conductive filler to prepare a new type of asphalt concrete and improve the efficiency of electrothermal snow and ice melting systems accordingly.The thermal conductivity of asphalt concrete prepared with different thermally conductive fillers was tested by a transient plane source method,and the related performances were measured.Then the temperature rise rate and surface temperature were studied through field heating tests.Finally,the actual ice melting efficiency of the thermally conductive asphalt concrete was evaluated using an effective electrothermal system.As shown by the experimental results,the composite made of SiC powder and carbon fiber has a high thermal conductivity.When SiC replaces mineral powder,the thermal conductivity of the asphalt mixture increases first and then decreases with the increase of carbon fiber content.In the present study,in particular,the thermal conductivity attained a peak when the carbon fiber content was 0.2%of the aggregate mass. 展开更多
关键词 Carbon fiber silicon carbide thermally conductive asphalt concrete road performance electrothermal snow melting
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Expert consensus on the diagnosis and therapy of endo-periodontal lesions
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作者 Bin chen Yanan Zhu +19 位作者 Minkui Lin Yangheng Zhang Yanfen Li Xiangying Ouyang Song Ge Jiang Lin Yaping Pan Yan Xu Yi Ding Shaohua Ge Faming chen Zhongchen Song Shaoyun Jiang Jiang Sun Lijun Luo Junqi Ling zhi chen Lin Yue Xuedong Zhou Fuhua Yan 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第3期381-389,共9页
Endo-periodontal lesions (EPLs) involve both the periodontium and pulp tissue and have complicated etiologies and pathogenic mechanisms,including unique anatomical and microbiological characteristics and multiple cont... Endo-periodontal lesions (EPLs) involve both the periodontium and pulp tissue and have complicated etiologies and pathogenic mechanisms,including unique anatomical and microbiological characteristics and multiple contributing factors.This etiological complexity leads to difficulties in determining patient prognosis,posing great challenges in clinical practice.Furthermore,EPL-affected teeth require multidisciplinary therapy,including periodontal therapy,endodontic therapy and others,but there is still much debate about the appropriate timing of periodontal therapy and root canal therapy.By compiling the most recent findings on the etiology,pathogenesis,clinical characteristics,diagnosis,therapy,and prognosis of EPL-affected teeth,this consensus sought to support clinicians in making the best possible treatment decisions based on both biological and clinical evidence. 展开更多
关键词 DIAGNOSIS PERIODONTAL LESIONS
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Expert consensus on irrigation and intracanal medication in root canal therapy
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作者 Xiaoying Zou Xin Zheng +25 位作者 Yuhong Liang chengfei Zhang Bing Fan Jingping Liang Junqi Ling Zhuan Bian Qing Yu Benxiang Hou zhi chen Xi Wei Lihong Qiu Wenxia chen Wenxi He Xin Xu Liuyan Meng chen Zhang Liming chen Shuli Deng Yayan Lei Xiaoli Xie Xiaoyan Wang Jinhua Yu Jin Zhao Song Shen Xuedong Zhou Lin Yue 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期26-35,共10页
Chemical cleaning and disinfection are crucial steps for eliminating infection in root canal treatment. However, irrigant selection or irrigation procedures are far from clear. The vapor lock effect in the apical regi... Chemical cleaning and disinfection are crucial steps for eliminating infection in root canal treatment. However, irrigant selection or irrigation procedures are far from clear. The vapor lock effect in the apical region has yet to be solved, impeding irrigation efficacy and resulting in residual infections and compromised treatment outcomes. 展开更多
关键词 TREATMENT IRRIGATION EXPERT
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Expert consensus on digital guided therapy for endodontic diseases 被引量:3
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作者 Xi Wei Yu Du +19 位作者 Xuedong Zhou Lin Yue Qing Yu Benxiang Hou zhi chen Jingping Liang Wenxia chen Lihong Qiu Xiangya Huang Liuyan Meng Dingming Huang Xiaoyan Wang Yu Tian Zisheng Tang Qi Zhang Leiying Miao Jin Zhao Deqin Yang Jian Yang Junqi Ling 《International Journal of Oral Science》 SCIE CAS CSCD 2023年第4期540-551,共12页
Digital guided therapy(DGT)has been advocated as a contemporary computer-aided technique for treating endodontic diseases in recent decades.The concept of DGT for endodontic diseases is categorized into static guided ... Digital guided therapy(DGT)has been advocated as a contemporary computer-aided technique for treating endodontic diseases in recent decades.The concept of DGT for endodontic diseases is categorized into static guided endodontics(SGE),necessitating a meticulously designed template,and dynamic guided endodontics(DGE),which utilizes an optical triangulation tracking system.Based on cone-beam computed tomography(CBCT)images superimposed with or without oral scan(OS)data,a virtual template is crafted through software and subsequently translated into a 3-dimensional(3D)printing for SGE,while the system guides the drilling path with a real-time navigation in DGE.DGT was reported to resolve a series of challenging endodontic cases,including teeth with pulp obliteration,teeth with anatomical abnormalities,teeth requiring retreatment,posterior teeth needing endodontic microsurgery,and tooth autotransplantation.Case reports and basic researches all demonstrate that DGT stand as a precise,time-saving,and minimally invasive approach in contrast to conventional freehand method.This expert consensus mainly introduces the case selection,general workflow,evaluation,and impact factor of DGT,which could provide an alternative working strategy in endodontic treatment. 展开更多
关键词 TEMPLATE utilize PRECISE
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In-situ observation on filiform corrosion propagation and its dependence on Zr distribution in Mg alloy WE43 被引量:2
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作者 zhi chen Huizhong Li +3 位作者 Xiaopeng Liang Ming-Chun Zhao Kelong Zhang Andrej Atrens 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第11期4282-4300,共19页
The direct industrial importance of the corrosion resistance in WE43 is best emphasized by its extensive use in the automotive, aerospace and electronic industries where weight reduction is a necessary requirement. In... The direct industrial importance of the corrosion resistance in WE43 is best emphasized by its extensive use in the automotive, aerospace and electronic industries where weight reduction is a necessary requirement. In this work, the corrosion especially the filiform corrosion in a 3.5 wt.% Na Cl solution and their dependence on the Zr distribution for WE43 were studied by weight loss tests, hydrogen evolution tests, electrochemical measurements and microscopic analyses. The Zr distribution significantly influenced the initiation and propagation of the filiform corrosion, and accordingly significantly influenced the corrosion rate. WE43 with a cluster Zr distribution displayed filiform corrosion throughout the entire surface with an irregular network distribution of filaments. WE43 with a uniform line Zr distribution exhibited only a few examples of linear filiform corrosion. WE43 with a dispersive Zr distribution exhibited no filiform corrosion. The stability of the corrosion film was responsible for the filiform corrosion. Anodic polarisation promoted the initiation and progression of the filiform corrosion,while cathodic polarisation had an inhibiting effect on the filiform corrosion. The serrated interface of the filiform corrosion increased the contact area between the substrate and the corrosive medium, and hence increased the corrosion rate. 展开更多
关键词 WE43 Mg alloy Filiform corrosion Zr distribution Corrosion rate
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DNA barcoding of fishes from Zhoushan coastal waters using mitochondrial COI and 12S rRNA genes 被引量:1
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作者 Yehui WANG Na SONG +3 位作者 Shude LIU zhi chen Anle XU Tianxiang GAO 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第5期1997-2009,共13页
Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan c... Accurate species identification is a key component of biodiversity research.DNA barcoding is an effective molecular method used for fish species identification.We aimed to study the DNA barcoding of fish in Zhoushan coastal waters,explore the differences and applicability of two gene fragments(12S rRNA and COI)of DNA barcoding in fish species identification,and established a comprehensive fish barcoding reference database.Two hundred and eighty-seven captured fish samples from Zhoushan coastal waters were identified using morphological characteristics and DNA barcoding.A total of 26412S rRNA sequences(belonging to eight orders,31 families,55 genera,and 66 species)and 188 COI sequences(belonging to seven orders,30 families,48 genera,and 58 species)were obtained.The lengths of the 12S rRNA sequences ranged from 165 to 178 bp,and the guanine-cytosine(GC)content was 45.37%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.10%and 26.66%,respectively.The length of the COI sequence ranged 574–655 bp,and the content of GC was 45.97%.The average 12S rRNA interspecific and intraspecific genetic distances(K2P)were 0.16%and 27.45%,respectively.The minimum interspecific genetic distances of 12S rRNA and COI(1.23%and 1.86%)were both greater than their maximum intraspecific genetic distances(2.42%and 8.66%).Three molecular analyses(NJ tree,ABGD,and GMYC)were performed to accurately identify and delineate species.Clustering errors occurred when the 12S rRNA sequences were delimited using the NJ tree method,and the delimitation results of ABGD and GMYC are consistent with the final species identification results.Our results demonstrate that DNA barcoding based on 12S rRNA and COI can be used as an effective tool for fish species identification,and 12S rRNA has good application prospects in the environmental DNA(eDNA)metabarcoding of marine fish. 展开更多
关键词 DNA barcoding cytochrome c oxidase subunit I(COI) 12S rRNA fish identification species delimitation Zhoushan coastal waters
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Examining the impact of early enteral nutritional support on postoperative recovery in patients undergoing surgical treatment for gastrointestinal neoplasms 被引量:1
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作者 zhi chen Bo Hong +2 位作者 Jiang-Juan He Qian-Qian Ye Qiao-Yi Hu 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2222-2233,共12页
BACKGROUND Patients with gastrointestinal tumors often suffer from poor nutritional status during treatment.Surgery is the main treatment for these patients,but the long postoperative recovery period is often accompan... BACKGROUND Patients with gastrointestinal tumors often suffer from poor nutritional status during treatment.Surgery is the main treatment for these patients,but the long postoperative recovery period is often accompanied by digestive and absorption dysfunction,leading to further deterioration of the nutritional status.Early enteral nutrition support is hypothesized to be helpful in improving this situation,but the exact effects have yet to be studied in depth.AIM To observe the effect of early enteral nutritional support on postoperative recovery in patients with surgically treated gastrointestinal tract tumors,with the expectation that by improving the nutritional status of patients,the recovery process would be accelerated and the incidence of complications would be reduced,thus improving the quality of life.METHODS A retrospective analysis of 121 patients with gastrointestinal tract tumors treated in our hospital from January 2020 to January 2023 was performed.Fifty-three of these patients received complete parenteral nutrition support as the control group for this study.The other 68 patients received early enteral nutritional support as the observation group of this study.The clinical indicators comparing the two groups included time to fever,time to recovery of postoperative bowel function,time to postoperative exhaustion,and length of hospital stay.The changes in immune function and nutritional indexes in the two groups were compared.Furthermore,we utilized the SF-36 scale to compare the changes in the quality of life between the two groups of patients.Finally,the occurrence of postoperative complications between the two patient groups was also compared.RESULTS The postoperative fever time,postoperative bowel function recovery time,postoperative exhaustion time,and hospitalization time were all higher in the control group than in the observation group(P<0.05).The levels of CD3+,CD4+,immunoglobulin(Ig)A,IgM,and IgG in the observation group were significantly higher than those in the control group at 1 d and 7 d postoperatively,while CD8+was lower than in the control group(P<0.05).Total protein,albumin,prealbumin,and transferrin levels were significantly higher in the observation group than in the control group at 7 d postoperatively(P<0.05).The SF-36 scores of patients in the observation group were significantly higher than those in the control group(P<0.0001).The overall incidence of adverse reactions after the intervention was significantly lower in the control group than in the observation group(P=0.021).CONCLUSION We found that patients with gastrointestinal tumors are nutritionally vulnerable,and early enteral nutrition support programs can improve the nutritional status of patients and speed up postoperative recovery.This program can not only improve the immune function of the patient and protect the intestinal function,but it can also help to improve the quality of life of the patient.However,this program will increase the incidence of complications in patients.Caution should be taken when adopting early enteral nutrition support measures for patients with gastric cancer.The patient's condition and physical condition should be comprehensively evaluated and closely monitored to prevent possible complications. 展开更多
关键词 Early enteral nutrition support Surgical treatment Gastrointestinal tumor Postoperative recovery Immune function
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TG酶在调控食物过敏原致敏性中的应用进展 被引量:2
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作者 支陈 施一凡 +1 位作者 闵星 邢广良 《常熟理工学院学报》 2023年第2期58-64,共7页
谷氨酰胺转氨酶(简称TG酶)可以催化蛋白质分子间或分子内通过酰基转移反应形成ε-(γ-谷氨酰基)赖氨酸交联键.通过共价交联将蛋白质分子粘合起来,改善蛋白质的凝胶性、乳化性等功能特性.本文综述了TG酶的来源、作用机制、常见的食物过... 谷氨酰胺转氨酶(简称TG酶)可以催化蛋白质分子间或分子内通过酰基转移反应形成ε-(γ-谷氨酰基)赖氨酸交联键.通过共价交联将蛋白质分子粘合起来,改善蛋白质的凝胶性、乳化性等功能特性.本文综述了TG酶的来源、作用机制、常见的食物过敏原类型以及TG酶在调控食物过敏原致敏性方面的应用,以期为TG酶在食物过敏的控制、低敏性或无敏性食品的研发,以及保障食物致敏原安全等方面的研究提供参考. 展开更多
关键词 谷氨酰胺转氨酶 食物过敏 致敏性 交联
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ATF6 aggravates apoptosis in early porcine embryonic development by regulating organelle homeostasis under high-temperature conditions
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作者 Ming-Hong Sun Wen-Jie Jiang +5 位作者 Xiao-Han Li Song-Hee Lee Geun Heo Dongjie Zhou zhi chen Xiang-Shun Cui 《Zoological Research》 SCIE CSCD 2023年第5期848-859,共12页
Activating transcription factor 6(ATF6),one of the three sensor proteins in the endoplasmic reticulum(ER),is an important regulator of ER stress-induced apoptosis.ATF6 resides in the ER and,upon activation,is transloc... Activating transcription factor 6(ATF6),one of the three sensor proteins in the endoplasmic reticulum(ER),is an important regulator of ER stress-induced apoptosis.ATF6 resides in the ER and,upon activation,is translocated to the Golgi apparatus,where it is cleaved by site-1 protease(S1P)to generate an amino-terminal cytoplasmic fragment.Although recent studies have made progress in elucidating the regulatory mechanisms of ATF6,its function during early porcine embryonic development under high-temperature(HT)stress remains unclear.In this study,zygotes were divided into four groups:control,HT,HT+ATF6 knockdown,and HT+PF(S1P inhibitor).Results showed that HT exposure induced ER stress,which increased ATF6 protein expression and led to a decrease in the blastocyst rate.Next,ATF6 expression was knocked down in HT embryos under microinjection of ATF6 double-stranded RNA(dsRNA).Results revealed that ATF6 knockdown(ATF6-KD)attenuated the increased expression of CHOP,an ER stress marker,and Ca2+release induced by HT.In addition,ATF6-KD alleviated homeostasis dysregulation among organelles caused by HT-induced ER stress,and further reduced Golgi apparatus and mitochondrial dysfunction in HT embryos.AIFM2 is an important downstream effector of ATF6.Results showed that ATF6-KD reduced the occurrence of AIFM2-mediated embryonic apoptosis at HT.Taken together,our findings suggest that ATF6 is a crucial mediator of apoptosis during early porcine embryonic development,resulting from HT-induced ER stress and disruption of organelle homeostasis. 展开更多
关键词 ATF6 EMBRYO High temperature ER stress Organelle homeostasis
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Europium anomalies in detrital zircons reveal the crustal thickness evolution of South China in Early Neoproterozoic
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作者 zhi chen 《Acta Geochimica》 EI CAS CSCD 2023年第4期739-746,共8页
The South China Block(SCB)is formed by the amalgamation of the Yangtze and Cathaysia blocks during the Early Neoproterozoic along the Jiangnan Orogen.However,the precise amalgamation time of these two blocks and the l... The South China Block(SCB)is formed by the amalgamation of the Yangtze and Cathaysia blocks during the Early Neoproterozoic along the Jiangnan Orogen.However,the precise amalgamation time of these two blocks and the location of the united SCB in the Rodinia supercontinent remain highly debatable.Various tectonic models have been proposed and they may have different implications for the crustal thickness evolution of the central SCB in Early Neoproterozoic.To evaluate these models,this paper uses a recently calibrated Eu/Eu*-inzircon proxy to reconstruct crustal thickness evolution of the central SCB during Early Neoproterozoic.I compiled and screened U–Pb ages and trace elements of 900–700 Ma detrital zircons from the central SCB and then calculated the zircon Eu/Eu*values.The age-binned average zircon Eu/Eu*displays a decreasing trend from 870 to 790 Ma,and thus indicates no significant crustal thickening event occurred during this time interval.This finding seems to be inconsistent with tectonic models that the Yangtze and Cathaysia blocks amalgamated during this time interval.Yet,given that available coupled detrital zircon U–Pb and trace element datasets are very limited,additional studies are warranted to further evaluate this hypothesis. 展开更多
关键词 South China Crustal thickness NEOPROTEROZOIC Detrital zircon Eu anomalies
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Federated learning based QoS-aware caching decisions in fog-enabled internet of things networks
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作者 Xiaoge Huang zhi chen +1 位作者 Qianbin chen Jie Zhang 《Digital Communications and Networks》 SCIE CSCD 2023年第2期580-589,共10页
Quality of Service(QoS)in the 6G application scenario is an important issue with the premise of the massive data transmission.Edge caching based on the fog computing network is considered as a potential solution to ef... Quality of Service(QoS)in the 6G application scenario is an important issue with the premise of the massive data transmission.Edge caching based on the fog computing network is considered as a potential solution to effectively reduce the content fetch delay for latency-sensitive services of Internet of Things(IoT)devices.Considering the time-varying scenario,the machine learning techniques could further reduce the content fetch delay by optimizing the caching decisions.In this paper,to minimize the content fetch delay and ensure the QoS of the network,a Device-to-Device(D2D)assisted fog computing network architecture is introduced,which supports federated learning and QoS-aware caching decisions based on time-varying user preferences.To release the network congestion and the risk of the user privacy leakage,federated learning,is enabled in the D2D-assisted fog computing network.Specifically,it has been observed that federated learning yields suboptimal results according to the Non-Independent Identical Distribution(Non-IID)of local users data.To address this issue,a distributed cluster-based user preference estimation algorithm is proposed to optimize the content caching placement,improve the cache hit rate,the content fetch delay and the convergence rate,which can effectively mitigate the impact of the Non-IID data set by clustering.The simulation results show that the proposed algorithm provides a considerable performance improvement with better learning results compared with the existing algorithms. 展开更多
关键词 Fog computing network IoT D2D communication Deep neural network Federated learning
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Assessment of the Mechanical Properties of Carbon-Fiber Heating Cables in Snow and Ice Melting Applications
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作者 zhiyong Yang Jiacheng Zhang +3 位作者 Henglin Xiao zhi chen Tian Bao Yin Liu 《Fluid Dynamics & Materials Processing》 EI 2023年第9期2267-2288,共22页
The use of carbon-fiber heating cables(CFHC)to achieve effective melting of snow and ice deposited on roads is a method used worldwide.In this study,tensile and compressive tests have been conducted to analyze the mech... The use of carbon-fiber heating cables(CFHC)to achieve effective melting of snow and ice deposited on roads is a method used worldwide.In this study,tensile and compressive tests have been conducted to analyze the mechan-ical properties of the CFHC and assess whether the maximum tensile and compressive strengths can meet the pavement design specifications.In order to study the aging produced by multiple cycles of heating and cooling,in particular,the CFHC was repeatedly heated in a cold chamber with an ambient temperature ranging between-20℃ and+40℃.Moreover,to evaluate how the strength of the pavement is affected by its presence,the CFHC was embedded at different depths and concrete blocks with different curing ages were subjected to relevant com-pression and splitting tensile tests.Numerical simulations based on the ANSYS software have also been performed and compared with the outcomes of the static loading tests.The results show that the CFHC embedded in the concrete does not affect the compressive splitting tensile strengths of the pavement.Overall,the CFHC meets the conditions required for continued use in road ice melting applications. 展开更多
关键词 Carbon fiber cable snow and ice melting concrete pavement compressive strength splitting tensile strength
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Mechanism of Herbal Medicine and Food Dandelion Effects May be Related to RNA or DNA Regulation: A Review
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作者 Ying Yang zhi chen 《Chinese Medicine》 2023年第2期79-93,共15页
Background: A dandelion is a common plant with a global growth distribution that has been used as a medicinal and food with no adverse effects. Purpose: In this article, the products and effects of dandelions are revi... Background: A dandelion is a common plant with a global growth distribution that has been used as a medicinal and food with no adverse effects. Purpose: In this article, the products and effects of dandelions are reviewed to help further in-depth studies and develop more products derived from dandelions in the future. Method: The literature about dandelion in various databases such as Pubmed is searched. Results: Dandelions have many effects, such as virus inhibition, anti-tumor activity, nutritional value, anti-aging, potential as a vaccine and alleviation of heat stress. The mechanism underlying these effects is analyzed and it was found that dandelions were regulated by RNA or DNA. Conclusion: As a medicinal and food, dandelions are safe and have many effects. Many products derived from dandelions have been developed. The metabolic regulation is related with ribonucleic acid or possibly deoxynucleic acid. Further in-depth studies should be conducted on the regulation of dandelions through RNA or DNA. There will likely be more products derived from dandelions in the future. 展开更多
关键词 DANDELION HERB Medicine FOOD NUTRITION RNA DNA Metabolism
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Astragaloside IV Ameliorates Inflammatory Damage in Mice with Acute Liver Failure
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作者 Ying Yang Meng Hong +1 位作者 Wenwen Lian zhi chen 《Chinese Medicine》 2023年第4期221-241,共21页
Acute liver failure is a life-threatening clinical syndrome with a high mortality rate. Currently, the research on Astragaloside IV in liver diseases primarily focuses on liver cancer, and there is limited understandi... Acute liver failure is a life-threatening clinical syndrome with a high mortality rate. Currently, the research on Astragaloside IV in liver diseases primarily focuses on liver cancer, and there is limited understanding of its mechanism in acute liver failure’s innate immunity. Therefore, this study aims to investigate the potential protective effect of Astragaloside IV on acute liver failure and its impact on innate immune cells. The study employed D-GalN/LPS-induced acute liver failure mouse models and employed various techniques such as a range of molecular and analytical techniques. The experimental results demonstrated that treatment with Astragaloside IV significantly reduced the inflammatory response, alleviated liver injury, and improved the survival rate of mice with acute liver failure induced by D-GalN/LPS. Further investigations revealed that AS-IV played a beneficial role by regulating the proportion of CD11b<sup>+</sup>Ly6C<sup>hi</sup> monocytes and the secretion of inflammatory cytokines and anti-inflammatory metabolites. These findings suggest that the pharmacological mechanism of AS-IV may involve targeted regulation of CD11b<sup>+</sup>Ly6C<sup>hi</sup> monocytes in both peripheral blood and liver. The implications of this study’s results are twofold. Firstly, they provide a basis for the clinical application of AS-IV in treating liver failure, offering potential therapeutic benefits. Secondly, they serve as a reference for further development of safer and more effective modified compounds. 展开更多
关键词 Astragaloside IV Acute Liver Failure INFLAMMATION MONOCYTE AUTOPHAGY
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Earthquake geochemical scientific expedition and research
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作者 Chang Lu Xiaocheng Zhou +5 位作者 zhi chen Zhaofei Liu Le Hu Fengxia Sun Giovanni Martinelli Ying Li 《Earthquake Research Advances》 CSCD 2023年第4期58-64,共7页
Large earthquakes can cause both casualties and economic losses, but they also provide invaluable opportunities for earthquake scientific research. Geofluids, due to their wide distribution, sensitive response to unde... Large earthquakes can cause both casualties and economic losses, but they also provide invaluable opportunities for earthquake scientific research. Geofluids, due to their wide distribution, sensitive response to underground conditions, and ease of observation, are widely applied in field investigations after earthquakes. Analyzing the origin of fluids, energy transfer processes, temperature/pressure conditions, and the spatial-temporal evolution of geofluids can provide valuable information concerning the mechanism of earthquake precursor anomalies, shortterm prediction methods, identification of the seismogenic faults, determination of earthquake risk, and the environmental impact of post-earthquake fluids. This article details post-earthquake scientific expeditions and research on fluid geochemistry in China and abroad, aimed at providing ideas and guidance for future scientific expedition work and geochemistry-related earthquake studies. 展开更多
关键词 Geofluids GEOCHEMISTRY Earthquake investigation
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全有机S型异质结PDI-Ala/S-C_(3)N_(4)光催化剂增强光催化性能 被引量:15
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作者 李喜宝 刘积有 +5 位作者 黄军同 何朝政 冯志军 陈智 万里鹰 邓芳 《物理化学学报》 SCIE CAS CSCD 北大核心 2021年第6期157-170,共14页
有机光催化剂以其适宜的氧化还原能带、低成本、高化学稳定性、分子结构和电子结构的可调控性而备受关注。PDI-Ala(N,N’-二(丙酸)-苝-3,4,9,10-四羧酸二亚胺)是一种新型的有机光催化剂,具有较强的可见光响应、低价带位置、强氧化能力... 有机光催化剂以其适宜的氧化还原能带、低成本、高化学稳定性、分子结构和电子结构的可调控性而备受关注。PDI-Ala(N,N’-二(丙酸)-苝-3,4,9,10-四羧酸二亚胺)是一种新型的有机光催化剂,具有较强的可见光响应、低价带位置、强氧化能力等特点。然而,低的光生电荷转移速率和高的载流子复合率限制了它的应用。由于g-C_(3)N_(4)存在芳香杂环结构且PDI-Ala的刚性平面结构存在着离域大π键,g-C_(3)N_(4)和PDI-Ala可以通过π–π相互作用和N―C键紧密结合。通过硫掺杂g-C_(3)N_(4)合成了S-C_(3)N_(4),其能带结构相比于g-C_(3)N_(4)更能与PDI-Ala相匹配。电子离域效应、内建电场和新形成的界面化学键共同促进了PDI-Ala与S-C_(3)N_(4)之间光生载流子的分离与迁移。因此,采用原位自组装的方法制备了一种由有机半导体PDI-Ala和S-C_(3)N_(4)组成的S型(阶梯型)异质结光催化剂。在制备过程中,PDI-Ala通过横向氢键和纵向π–π堆积自组装成超分子。采用X射线衍射(XRD)、透射电子显微镜(TEM)、能谱仪(EDS)、X射线光电子能谱(XPS)、紫外可见漫反射光谱(UVVis-DRS)、电化学阻抗谱(EIS)、Mott-Schottky曲线(MS)等多种表征方法,对PDI-Ala/S-C_(3)N_(4)光催化剂的晶体结构、形貌、价态、光学性能、稳定性和能带结构进行了系统的分析和研究;利用密度泛函理论(DFT)计算了材料的功函数和界面耦合特性。研究了合成的光催化剂在H2O2生产中的光催化活性以及在可见光照射下对四环素(TC)和对硝基苯酚(PNP)的降解作用。该S型异质结具有能带匹配和紧密的界面结合,加速了分子间的电子转移,拓宽了异质结的可见光响应范围。此外,在PDI-Ala/S-C_(3)N_(4)光催化降解反应过程中,产生并积累了多种活性物种(h^(+)、·O^(-)_(2)和H_(2)O_(2))。因此,PDI-Ala/SC_(3)N_(4)异质结在降解TC、PNP和H_(2)O_(2)生产方面表现出更强的光催化性能。在可见光照射下,30%PDI-Ala/S-C_(3)N_(4)样品在90 min内去除了90%的TC,H_(2)O_(2)的产率为28.3μmol·h^(-1)·g^(-1),分别是PDI-Ala的2.9倍和S-C_(3)N_(4)的1.6倍。结果表明,由苝二酰亚胺(PDIs)基超分子和S-C_(3)N_(4)组成的全有机光催化剂可有效地用于降解有机污染物和生产H_(2)O_(2)。本研究不仅为全有机S型异质结的设计提供了一种新的策略,而且为理解具有有效界面键合的异质结构催化剂的构效关系提供了新的见解和参考。 展开更多
关键词 可见光光催化 S型异质结 C_(3)N_(4) Π-Π相互作用 H_(2)O_(2)
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