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Efficacy and Safety of Iron Isomaltoside Compared with an Oral Iron Supplement in the Management of Patients with Iron Deficiency Anemia
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作者 Zhimin Wu Chunxiao Zhou +4 位作者 Chunyan Wu Qiao Song Shilyu Chen wen zhang Shaoling Wu 《Open Journal of Blood Diseases》 2024年第1期17-30,共14页
Objective: To evaluate the treatment outcome of iron isomaltoside compared with an oral iron supplement in the management of iron deficiency anemia (IDA). Methods: The study included patients with IDA who visited the ... Objective: To evaluate the treatment outcome of iron isomaltoside compared with an oral iron supplement in the management of iron deficiency anemia (IDA). Methods: The study included patients with IDA who visited the Outpatient Clinic of the Department of Hematology, the Affiliated Hospital of Qingdao University from October 2021 to August 2022 and met the inclusion and exclusion criteria. According to the actual application of iron supplementation, the patients were divided into two groups: iron isomaltoside treatment group and oral iron treatment group. Baseline measurements were collected before the start of treatment, and measurements were collected subsequently at intervals of 1 week, 1 month, and 3 months. The hematological parameters analyzed included Hemoglobin (Hb), Mean corpuscular hemoglobin (MCH), Mean Hemoglobin content (MCH), Mean corpuscular Hemoglobin concentration (MCHC), and Platelet (Plt). Safety data and adverse event profiles were recorded. Results: Intra-group comparisons: After 1 month of treatment, the Hb significantly improved (P 0.05). Inter-group comparisons: The biochemical parameters were significantly improved (P 0.05) in the iron isomaltoside group compared with those in the oral iron group after 1 month of iron supplementation in patients with mild and moderate anemia. Adverse reactions were tolerable for the patients in both iron isomaltoside group and oral iron group. Only 1 patient in iron isomaltoside group developed anaphylactic shock during medication and recovered after aggressive rescue. Conclusions: Iron isomaltoside which increases Hb more rapidly compared with the oral iron supplementation has few adverse reactions and good acceptance. 展开更多
关键词 ANEMIA IRON-DEFICIENCY Drug Therapy Iron Isomaltoside 1000 Treatment Outcome
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HBV相关肝病患者外周血T细胞及细胞因子水平研究
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作者 刘晨瑞 李亚萍 +5 位作者 王怡恺 张雯 郝苗 王文俊 李婷 党双锁 《世界华人消化杂志》 CAS 2024年第4期293-301,共9页
背景乙型肝炎病毒(hepatitis B virus,HBV)相关慢性肝病患者外周血T细胞及细胞因子水平与患者免疫功能状态密切相关,不同疾病程度的HBV相关肝病患者的T细胞、细胞因子水平及与肝病阶段的相关性值得进一步探究.目的探究不同阶段HBV相关... 背景乙型肝炎病毒(hepatitis B virus,HBV)相关慢性肝病患者外周血T细胞及细胞因子水平与患者免疫功能状态密切相关,不同疾病程度的HBV相关肝病患者的T细胞、细胞因子水平及与肝病阶段的相关性值得进一步探究.目的探究不同阶段HBV相关慢性肝病患者外周血T细胞亚群计数、细胞因子变化特点及关联性.方法本研究为一项观察性研究,共纳入慢性乙型肝炎(chronic hepatitis B,CHB)患者65例,肝硬化失代偿期(decompensated cirrhosis,DCC)患者122例,肝细胞癌(hepatocellular carcinoma,HCC)患者109例,收集患者一般信息、病史、治疗情况及实验室检查结果、Child-Paugh分级及HCC患者肿瘤巴塞罗那分期,分析各项指标,尤其是T细胞亚群计数及细胞因子的组间差异及特征.结果HBV相关肝硬化、HCC患者外周血CD8^(+)T细胞水平与Child分级A到C呈负相关.HCC患者CD8^(+)T细胞绝对计数显著低于DCC[240(150-379)cells/μLvs 277(154-435)cells/μL,P<0.05]及CHB[240(150-379)cells/μL vs 452(269-706)cells/μL,P<0.001]患者.白细胞介素(interleukin,IL)-6、IL-8、肿瘤坏死因子(tumor necrosis factor,TNF)-α在HCC组均最高.DCC、HCC患者Child-Paugh分级越差,CD3^(+)、CD8^(+)T细胞水平越低,IL-6水平越高.HCC患者CD3^(+)、CD8^(+)T细胞水平随着肿瘤巴塞罗那分期由A到D呈下降趋势,IL-6呈上升趋势.且肝硬化、HCC患者CD3^(+)(r=-0.340,P<0.001)、CD8^(+)(r=-0.353,P<0.001)T细胞水平与IL-6升高水平呈显著负相关.结论HBV相关肝硬化、HCC患者外周血CD8^(+)T细胞计数与Child分级(由A到C)呈负相关,且IL-6水平与CD8^(+)T细胞计数存在负相关关系. 展开更多
关键词 乙型肝炎病毒 肝硬化失代偿期 肝细胞癌 T细胞亚群计数 细胞因子
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基于切片采样-马尔科夫链蒙特卡洛模拟的高比例新能源电力系统等效惯量概率评估
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作者 王强强 姚良忠 +4 位作者 徐箭 程帆 毛蓓琳 闻章 陈汝斯 《电网技术》 EI CSCD 北大核心 2024年第1期140-149,共10页
风电、光伏新能源发电功率的不确定性给高比例新能源电力系统的等效惯量评估带来了新的挑战。基于确定性的惯量评估方法不能有效反映全分析时段高比例新能源电力系统惯量的时序变化态势。为了评估新能源波动所引起的系统惯量不确定性,... 风电、光伏新能源发电功率的不确定性给高比例新能源电力系统的等效惯量评估带来了新的挑战。基于确定性的惯量评估方法不能有效反映全分析时段高比例新能源电力系统惯量的时序变化态势。为了评估新能源波动所引起的系统惯量不确定性,该文提出了一种基于切片采样–马尔科夫链蒙特卡洛模拟(slice sample Markov chain Monte Carlo,S-MCMC)的系统等效惯量概率评估方法。首先,对高比例新能源电力系统惯量组成及特性进行了分析,并对同步旋转设备的有效机械惯量、风电光伏电源的有效虚拟惯量进行量化计算。然后,基于Copula函数建立风速和光照强度之间的相关性模型,利用S-MCMC对系统等效惯量进行概率评估,从而得到系统等效惯量时序变化区间。最后,以改进的IEEE 39节点系统进行仿真分析,验证了所提出方法及分析结果的有效性。 展开更多
关键词 高比例新能源电力系统 不确定性 等效惯量 概率评估 时序变化区间
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Correlation of personality with individual reproductive success in shrub-nesting birds depends on their life history style
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作者 Jianchuan Li wen zhang +5 位作者 Ningning Sun Yujie Wang Lifang Gao Ran Feng Liqing Fan Bo Du 《Avian Research》 SCIE CSCD 2024年第1期42-49,共8页
Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain ... Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species. 展开更多
关键词 BOLDNESS Life history style PERSONALITY Reproductive success Transcriptome analysis
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Degradable magnesium alloy suture promotes fibrocartilaginous interface regeneration in a rat rotator cuff transosseous repair model
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作者 Baoxiang zhang wen zhang +5 位作者 Fei zhang Chao Ning Mingyang An Ke Yang Lili Tan Qiang zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期384-393,共10页
Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional sutures.In the present... Despite transosseous rotator cuff tear repair using sutures is widely accepted for tendon-bone fixation,the fibrocartilaginous enthesis regeneration is still hardly achieved with the traditional sutures.In the present work,degradable magnesium(Mg)alloy wire was applied to suture supraspinatus tendon in a rat acute rotator cuff tear model with Vicryl Plus 4±0 absorbable suture as control.The shoulder joint humerus-supraspinatus tendon complex specimens were retrieved at 4,8,and 12 weeks after operation.The Mg alloy suture groups showed better biomechanical properties in terms of ultimate load to failure.Gross observation showed that hyperplastic response of the scar tissue at the tendon-bone interface is progressively alleviated over time in the both Mg alloy suture and Vicryl suture groups.In the histological analysis,for Mg alloy suture groups,chondrocytes appear to proliferate at 4 weeks postoperatively,and the tendon-bone interface showed an orderly structural transition zone at 8 weeks postoperatively.The collagenous fiber tended to be aligned and the tendon-bone interlocking structures apparently formed,where transitional structure from unmineralized fibrocartilage to mineralized fibrocartilage was closer to the native fibrocartilaginous enthesis.In vivo degradation of the magnesium alloy wire was completed within 12 weeks.The results indicated that Mg alloy wire was promising as degradable suture with the potential to promotes fibrocartilaginous interface regeneration in rotator cuff repair. 展开更多
关键词 Rotator cuff repair Mg alloy wire Tendon-bone healing Fibrocartilaginous interface
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An improved TDE technique for derivation of 2D turbulence structures based on GPI data in toroidal plasma
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作者 王威策 程钧 +12 位作者 石中兵 严龙文 黄治辉 弋开阳 吴娜 何钰 邹千 陈熙 张文 陈建 聂林 季小全 钟武律 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期131-137,共7页
This paper reports an improved time-delay estimation(TDE)technique for the derivation of turbulence structures based on gas-puff imaging data.The improved TDE technique,integrating an inverse timing search and hierarc... This paper reports an improved time-delay estimation(TDE)technique for the derivation of turbulence structures based on gas-puff imaging data.The improved TDE technique,integrating an inverse timing search and hierarchical strategy,offers superior accuracy in calculating turbulent velocity field maps and analyzing blob dynamics,which has the power to obtain the radial profiles of equilibrium poloidal velocity,blob size and its radial velocity,even the fluctuation analysis,such as geodesic acoustic modes and quasi-coherent mode,etc.This improved technique could provide important 2D information for the study of edge turbulence and blob dynamics,advancing the understanding of edge turbulence physics in fusion plasmas. 展开更多
关键词 gas-puff imaging TDE method TURBULENCE velocity field map
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Single-center retrospective study of the diagnostic value of doubleballoon enteroscopy in Meckel’s diverticulum with bleeding
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作者 Tian He Chao Yang +10 位作者 Jing Wang Ji-Sheng Zhong Ai-Hua Li Ya-Jing Yin Li-Ling Luo Chun-Mei Rao Nian-Fen Mao Qiang Guo Zan Zuo wen zhang Ping Wan 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期1043-1054,共12页
BACKGROUND The study aimed to analyze the characteristic clinical manifestations of patients with intestinal disease Meckel’s diverticulum(MD)complicated by digestive tract hemorrhage.Moreover,we aimed to evaluate th... BACKGROUND The study aimed to analyze the characteristic clinical manifestations of patients with intestinal disease Meckel’s diverticulum(MD)complicated by digestive tract hemorrhage.Moreover,we aimed to evaluate the value of double-balloon enteroscopy(DBE)in MD diagnosis and the prognosis after laparoscopic diverticula resection.AIM To evaluate the value of DBE in the diagnosis and the prognosis after laparoscopic diverticula resection for MD with bleeding.METHODS The study retrospectively analyzed relevant data from 84 MD patients treated between January 2015 and March 2022 and recorded their clinical manifestations,auxiliary examination,and follow-up after laparoscopic resection of diverticula.RESULTS(1)Among 84 MD patients complicated with hemorrhage,77 were male,and 7 were female with an average age of 31.31±10.75 years.The incidence was higher in men than in women of different ages;(2)Among the 84 MD patients,65(78.40%)had defecated dark red stools,and 50(58.80%)had no accompanying symptoms during bleeding,indicating that most MD bleeding appeared a dark red stool without accompanying symptoms;(3)The shock index of 71 patients(85.20%)was<1,suggesting that the blood loss of most MD patients was less than 20%–30%,and only a few patients had a blood loss of>30%;(4)The DBE-positive rate was 100%(54/54),99mTcpertechnetate-positive scanning rate was 78%(35/45)compared with capsule endoscopy(36%)and small intestine computed tomography(19%).These results suggest that DBE and 99mTc-pertechnetate scans had significant advantages in diagnosing MD and bleeding,especially DBE was a highly precise examination method in MD diagnosis;(5)A total of 54 MD patients with hemorrhage underwent DBE examination before surgery.DBE endoscopy revealed many mucosal manifestations including normal appearance,inflammatory changes,ulcerative changes,diverticulum inversion,and nodular hyperplasia,with ulcerative changes being the most common(53.70%).This suggests that diverticular mucosal ulcer was the main cause of MD and bleeding;and(6)Laparoscopic dissection of diverticulae was performed in 76 patients,The patients who underwent postoperative follow-up did not experience any further bleeding.Additionally,follow-up examination of the 8 cases who had declined surgery revealed that 3 of them experienced a recurrence of digestive tract bleeding.These findings indicate that laparoscopic diverticula resection in MD patients complicated by bleeding had a favorable prognosis.CONCLUSION Bleeding associated with MD was predominantly observed in male adolescents,particularly at a young age.DBE was a highly precise examination method in MD diagnosis.Laparoscopic diverticula resection effectively prevented MD bleeding and had a good prognosis. 展开更多
关键词 Meckel’s diverticulum with bleeding Double-balloon colonoscopy 99mTc-pertechnetate scanning Capsule endoscopy Ectopic gastric mucosa
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迪那2凝析气田全生命开采周期纵横向出砂规律探索
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作者 刘洪涛 文章 +5 位作者 涂志雄 张宝 景宏涛 易俊 孔嫦娥 于小童 《特种油气藏》 CAS CSCD 北大核心 2023年第3期148-154,共7页
塔里木油田迪那2凝析气田属于高温高压、低孔低渗、中—高胶结强度裂缝性砂岩气藏,具有低孔低渗特点,传统观点均认为该类型储层不存在出砂问题,但自2009年投产至今,21口井取到砂样,出砂情况普遍,已成为影响气田稳产的一个关键技术难题... 塔里木油田迪那2凝析气田属于高温高压、低孔低渗、中—高胶结强度裂缝性砂岩气藏,具有低孔低渗特点,传统观点均认为该类型储层不存在出砂问题,但自2009年投产至今,21口井取到砂样,出砂情况普遍,已成为影响气田稳产的一个关键技术难题。为此,建立了多孔弹塑性3D出砂流固耦合模型,利用数值模拟方法,对迪那2气田开展全方位出砂量预测。研究表明:迪那2气田出砂过程可划分为少量出砂、出砂递增、出砂加剧及稳定出砂4个阶段;重度出砂区域在X-6、X-7、X-8井周围,出砂量从气田中部往四周逐步降低,重点出砂层位在库姆格列木群E_(1-2)km^(2)组。经现场实测数据验证,出砂量预测误差在15%以内,说明该出砂量预测方法具有实用性。该研究可为油田制订合理防砂对策和高效开发提供技术支持。 展开更多
关键词 出砂机理 出砂量预测 出砂规律 凝析气田 迪那2气田 塔里木
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双向主客体作用促进水溶液中选择性光催化CO_(2)还原与醇氧化
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作者 张雯 宋彩彩 +4 位作者 王嘉蔚 蔡舒婷 高梦语 冯有祥 鲁统部 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第9期176-186,共11页
CO_(2)还原与H_(2)O氧化耦合被认为是将太阳能转化为化学能的理想方法.然而,H_(2)O氧化反应的显著动力学障碍限制了该类反应的转化效率.此外,额外的电子牺牲剂的消耗不仅在经济上不可行,而且浪费了光生空穴的氧化能力.因此,将CO_(2)还... CO_(2)还原与H_(2)O氧化耦合被认为是将太阳能转化为化学能的理想方法.然而,H_(2)O氧化反应的显著动力学障碍限制了该类反应的转化效率.此外,额外的电子牺牲剂的消耗不仅在经济上不可行,而且浪费了光生空穴的氧化能力.因此,将CO_(2)还原与有机物的有效氧化相结合将是有效利用太阳能和解决能源危机的有效途径之一.对于包含光敏剂、催化剂和反应底物的离散光催化体系来说,电子转移效率主要由离散组分之间的扩散过程控制.为了提高光反应组分之间的电子转移效率,研究人员尝试通过共价键在催化剂和光敏剂之间建立“桥梁”,从而获得更快的电子转移速率.然而,该类体系存在合成过程复杂、共价键断裂及使用贵金属等问题.与共价键相比,非共价体系更便于合成,且具有更好的稳定性.本文利用双向主客体相互作用构筑高效光催化体系,其中水溶性β-环糊精修饰的CdS纳米晶与CoTPP(助催化剂)和有机醇(反应底物)均通过非共价主客体作用连接,促使光生电子和光生空穴的同步快速消耗.核磁共振氢谱结果表明,环糊精作为主体分子可以识别客体分子四苯基卟啉钴与呋喃醇.利用Job曲线测得环糊精与四苯基卟啉钴以及呋喃醇的键合比分别为2:1和1:1.紫外-可见吸收光谱结果表明,环糊精与四苯基卟啉钴以及呋喃醇之间存在不同强度的主客体键合.光催化CO_(2)还原反应与呋喃醇氧化性能测试结果表明,与无配体的Cd S纳米晶(CdS-BF_(4))以及其它配体(油酸、2-巯基乙醇和硫代甘油)修饰的Cd S纳米晶相比,环糊精修饰的CdS-CD纳米晶在水相中表现出更高的CO_(2)还原为HCOOH的活性与选择性,同时,表现出最佳的呋喃醇氧化活性与选择性.相反,表面无配体的Cd S-BF4纳米晶活性较低,且有严重的析氢副反应发生.为了更好地理解双向主客体相互作用对光反应性能的贡献,利用一系列稳态和瞬态荧光光谱实验研究了三个组分之间的电子转移过程.结果表明,CdS-CD与Co TPP之间以及Cd S-CD与呋喃醇之间的双向主客体相互作用可以有效促进这些组分之间的电子转移过程.原位漫反射傅立叶变换红外光谱和密度泛函理论研究表明,随着光辐射时间的增加,HCOO*信号逐渐增强.电子顺磁共振波谱结果表明,在光催化呋喃醇氧化的过程中产生了呋喃醇苄基自由基.在以上光还原和光氧化的全反应过程中,双向主客体作用同时将助催化剂和反应物聚集在吸光物质Cd SNCs表面,这对于促进快速电子/空穴转移和随后的氧化还原反应发挥着关键作用.综上所述,选择合适的有机物不仅可以促进光还原反应的发生,还可以生产更高附加值的化学品.本文采用双向主客体策略构建新型的人工光合作用系统,为构建具有实际应用潜能的人工光合作用系统提供了新的思路. 展开更多
关键词 人工光合成 主客体相互作用 CO_(2)还原 醇氧化 快速电子转移
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等离激元催化反应动力学研究装置
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作者 张文 周勇 +6 位作者 陈伟 王天骏 秦召贤 李杲 任泽峰 杨学明 周传耀 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2023年第3期249-258,I0099,共11页
等离激元催化是利用金属纳米颗粒的局域表面等离激元来驱动化学反应的现象,已经发展成为多相催化的一个新兴研究领域.然而,实验研究中温度测量不准和反应物吸附状态不明确导致等离激元催化反应的微观机制存在争议.为了研究等离激元催化... 等离激元催化是利用金属纳米颗粒的局域表面等离激元来驱动化学反应的现象,已经发展成为多相催化的一个新兴研究领域.然而,实验研究中温度测量不准和反应物吸附状态不明确导致等离激元催化反应的微观机制存在争议.为了研究等离激元催化反应动力学,本文设计搭建了一台基于在线质谱检测的装置,通过对反应器的改进来解决温度测量和吸附状态识别的问题.相比于传统设计中仅安装一个热偶,本文在反应器中安装了三个热偶.基于传热模型,这种多点测温技术可以定量计算出催化剂的有效温度以及热反应的贡献.此外,在装置中集成了程序升温脱附谱,用于测量反应物的吸附状态.通过对模型催化反应Au/TiO_(2)等离激元催化H_(2)+D_(2)→HD的定量测量,测试了该装置的性能,明确了H_(2)/D_(2)在Au/TiO_(2)界面的解离吸附和非热反应对HD生成的贡献,证明了该装置在等离激元催化反应动力学研究方面的能力. 展开更多
关键词 等离激元催化 反应装置 反应机制 驱动力 多点温度测量 吸附状态识别
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基于扎根理论的北京市大学生外卖餐饮购买行为影响因素与干预关键点研究
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作者 石珺怡 靖婷 +9 位作者 宋丽霞 申贵元 杨智凯 文彰 王宏博 张玉梅 解清 樊蕊 姚尧 许雅君 《中国健康教育》 北大核心 2023年第7期632-636,共5页
目的构建北京市大学生外卖餐饮购买行为的影响因素理论模型,确定干预关键点,为促进北京高校学生健康餐饮提供建议。方法基于扎根理论,于2021年12月采用滚雪球法招募北京市8所高校24名学生进行半结构化访谈,对文本资料进行三级编码构建... 目的构建北京市大学生外卖餐饮购买行为的影响因素理论模型,确定干预关键点,为促进北京高校学生健康餐饮提供建议。方法基于扎根理论,于2021年12月采用滚雪球法招募北京市8所高校24名学生进行半结构化访谈,对文本资料进行三级编码构建理论模型。结果共生成464个编码参考点,概括为67个子范畴,提炼为17个范畴,最终归纳为外卖因素(217参考点)、个人因素(101参考点)、环境因素(93参考点)和人际因素(53参考点)4个主范畴。餐饮质量与配送情况等外卖相关因素是影响学生外卖餐饮购买行为的最主要因素,点餐经历、健康认知等个人因素和校内食堂设置、课业压力、社会舆论等环境因素居于次位,而同学与家长对于外卖的态度倾向等人际因素则较少影响学生的外卖餐饮购买行为。结论外卖餐饮自身各方面因素对于学生的购买行为影响较大,且学生购买外卖的需求难以直接抑制;高校食堂水平发挥着十分重要的作用;大多数受访者对食品营养认识不足。对高校而言,环境因素中的学校食堂水平、个人因素中的健康认知可作为干预关键点。 展开更多
关键词 外卖餐饮 大学生 影响因素 扎根理论
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A Survey on Negative Transfer 被引量:3
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作者 wen zhang Lingfei Deng +1 位作者 Lei zhang Dongrui Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第2期305-329,共25页
Transfer learning(TL)utilizes data or knowledge from one or more source domains to facilitate learning in a target domain.It is particularly useful when the target domain has very few or no labeled data,due to annotat... Transfer learning(TL)utilizes data or knowledge from one or more source domains to facilitate learning in a target domain.It is particularly useful when the target domain has very few or no labeled data,due to annotation expense,privacy concerns,etc.Unfortunately,the effectiveness of TL is not always guaranteed.Negative transfer(NT),i.e.,leveraging source domain data/knowledge undesirably reduces learning performance in the target domain,and has been a long-standing and challenging problem in TL.Various approaches have been proposed in the literature to address this issue.However,there does not exist a systematic survey.This paper fills this gap,by first introducing the definition of NT and its causes,and reviewing over fifty representative approaches for overcoming NT,which fall into three categories:domain similarity estimation,safe transfer,and NT mitigation.Many areas,including computer vision,bioinformatics,natural language processing,recommender systems,and robotics,that use NT mitigation strategies to facilitate positive transfers,are also reviewed.Finally,we give guidelines on NT task construction and baseline algorithms,benchmark existing TL and NT mitigation approaches on three NT-specific datasets,and point out challenges and future research directions.To ensure reproducibility,our code is publicized at https://github.com/chamwen/NT-Benchmark. 展开更多
关键词 Domain adaptation domain similarity negative transfer positive transfer transfer learning
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乳化热固性树脂体系构建及其封堵性能评价
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作者 甄恩龙 张雯 +2 位作者 钱真 杜若彤 王洋 《日用化学工业(中英文)》 CAS 北大核心 2023年第6期649-657,共9页
随着高温(储层温度130℃)裂缝油藏开展水驱作业,注入水沿裂缝窜进问题日益突出。环氧树脂高温条件下固化后具有强度高、耐老化的特点,是一种有潜力的高温堵剂。针对环氧树脂不易注入、潮湿条件下难固化的问题,采用相反转法乳化环氧树脂... 随着高温(储层温度130℃)裂缝油藏开展水驱作业,注入水沿裂缝窜进问题日益突出。环氧树脂高温条件下固化后具有强度高、耐老化的特点,是一种有潜力的高温堵剂。针对环氧树脂不易注入、潮湿条件下难固化的问题,采用相反转法乳化环氧树脂,初选多种乳化剂分别以自来水和模拟地层水为水相,对环氧树脂E-44进行乳化,筛选出同时适用于两种水相的乳化剂;然后进行单因素实验,分别研究搅拌速度、乳化温度、加水速度、乳化剂质量分数、油水体积比工艺因素对环氧树脂相反转过程及乳状液性能的影响;最后采用正交试验综合分析各因素的影响水平并确定较优乳化工艺参数,建立乳化体系。差示扫描量热实验结果表明,该体系的固化温度为129.5℃,在储层温度下固化后具有良好的封堵效果。 展开更多
关键词 环氧树脂 乳状液 固化剂 热稳定性 封堵性
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Enabling stable 4.6 V LiCoO_(2) cathode through oxygen charge regulation strategy
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作者 wen zhang Xiaoyu zhang +11 位作者 Fangyuan Cheng Meng Wang Jing Wan Yuyu Li Jia Xu Yi Liu Shixiong Sun Yue Xu Chun Fang Qing Li Jiantao Han Yunhui Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期557-565,I0014,共10页
LiCoO_(2) is the preferred cathode material for consumer electronic products due to its high volumetric energy density. However, the unfavorable phase transition and surface oxygen release limits the practical applica... LiCoO_(2) is the preferred cathode material for consumer electronic products due to its high volumetric energy density. However, the unfavorable phase transition and surface oxygen release limits the practical application of LiCoO_(2)at a high-voltage of 4.6 V to achieve a higher energy density demanded by the market. Herein, both bulk and surface structures of LiCoO_(2)are stabilized at 4.6 V through oxygen charge regulation by Gd-gradient doping. The enrichment of highly electropositive Gd on LiCoO_(2) surface will increase the effective charge on oxygen and improve the oxygen framework stability against oxygen loss.On the other hand, Gd ions occupy the Co-sites and suppress the unfavorable phase transition and microcrack. The modified LiCoO_(2) exhibits superior cycling stability with capacity retention of 90.1% over 200 cycles at 4.6 V, and also obtains a high capacity of 145.7 m Ah/g at 5 C. This work shows great promise for developing high-voltage LiCoO_(2) at 4.6 V and the strategy could also contribute to optimizing other cathode materials with high voltage and large capacity, such as cobalt-free high-nickel and lithiumrich manganese-based cathode materials. 展开更多
关键词 Li-ion batteries 4.6 V LiCoO_(2) Gd-gradient doping Oxygen charge Cycle stability
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Simultaneous realization of high sulfur utilization and lithium dendrite-free via dual-effect kinetic regulation strategy toward lithium-sulfur batteries
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作者 Xinqi Zhao Xiaohong Sun +8 位作者 Ruisong Guo Song Wang Fuyun Li Tingting Li wen zhang Chunming Zheng Lingyun An Leichao Meng Xudong Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期260-271,I0007,共13页
With the high theoretical specific capacity and energy density,lithium-sulfur batteries(LSBs)have been intensively studied as promising candidates for energy storage devices.However,LSBs are largely hindered by inferi... With the high theoretical specific capacity and energy density,lithium-sulfur batteries(LSBs)have been intensively studied as promising candidates for energy storage devices.However,LSBs are largely hindered by inferior sulfur utilization and uncontrollable dendritic growth.Herein,a hierarchical functionalization strategy of stepwise catalytic-adsorption-conversion for sulfur species via the synergetic of the efficiently catalytic host cathode and light multifunctional interlayer has been proposed to concurrently address the issues arising on the dual sides of the LSBs.The multi-layer SnS_(2) micro-flowers embedded into the natural three-dimensional(3D)interconnected carbonized bacterial cellulose(CBC)nanofibers are fabricated as the sulfur host that provides numerous catalytic sites for the rapid catalytic conversion of sulfur species.Moreover,the distinctive CBC-based SnO_(2)-SnS_(2) heterostructure network accompanied high conductive carbon nanofibers as the multifunctional interlayer promotes the rapid anchoringdiffusion-conversion of lithium polysulfides,Li^(+)flux redistribution,and uniform Li deposition.LSBs equipped with our strategy exhibit a high reversible capacity of 1361.5 m A h g^(-1)at 0.2 C and superior cycling stability with an ultra-low capacity fading of 0.031%per cycle in 1000 cycles at 1.5 C and 0.046%at 3 C.A favorable specific capacity of 859.5 m A h g^(-1)at 0.3 C is achieved with a high sulfur mass loading of 5.2 mg cm^(-2),highlighting the potential of practical application.The rational design in this work can provide a feasible solution for high-performance LSBs and promote the development of advanced energy storage devices. 展开更多
关键词 Lithium-sulfur battery Catalytic sulfur host Multifunctional interlayer Polysulfides adsorbing-conversion Dendrite-free
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The coupled deep neural networks for coupling of the Stokes and Darcy–Forchheimer problems
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作者 岳靖 李剑 +1 位作者 张文 陈掌星 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期123-136,共14页
We present an efficient deep learning method called coupled deep neural networks(CDNNs) for coupling of the Stokes and Darcy–Forchheimer problems. Our method compiles the interface conditions of the coupled problems ... We present an efficient deep learning method called coupled deep neural networks(CDNNs) for coupling of the Stokes and Darcy–Forchheimer problems. Our method compiles the interface conditions of the coupled problems into the networks properly and can be served as an efficient alternative to the complex coupled problems. To impose energy conservation constraints, the CDNNs utilize simple fully connected layers and a custom loss function to perform the model training process as well as the physical property of the exact solution. The approach can be beneficial for the following reasons: Firstly, we sample randomly and only input spatial coordinates without being restricted by the nature of samples.Secondly, our method is meshfree, which makes it more efficient than the traditional methods. Finally, the method is parallel and can solve multiple variables independently at the same time. We present the theoretical results to guarantee the convergence of the loss function and the convergence of the neural networks to the exact solution. Some numerical experiments are performed and discussed to demonstrate performance of the proposed method. 展开更多
关键词 scientific computing machine learning the Stokes equations Darcy–Forchheimer problems Beavers–Joseph–Saffman interface condition
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25-Hydroxyvitamin D Is Associated with Islet Homeostasis in Type-2 Diabetic Patients with Abdominal Obesity
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作者 Qing LI wen zhang +5 位作者 Bing HAN Yu-ying WANG Heng WAN Min zhang Ning-jian WANG Ying-li LU 《Current Medical Science》 SCIE CAS 2023年第5期919-926,共8页
Objective Isletαcells input is essential for insulin secretion fromβcells.The present study aims to investigate the association between 25-hydroxyvitamin D[25(OH)D]and islet function homeostasis in type-2 diabetes(T... Objective Isletαcells input is essential for insulin secretion fromβcells.The present study aims to investigate the association between 25-hydroxyvitamin D[25(OH)D]and islet function homeostasis in type-2 diabetes(T2D)patients.Methods A total of 4670 T2D patients from seven communities in Shanghai,China were enrolled.The anthropometric indices,biochemical parameters,serum 25(OH)D,and islet function[including C-peptide(C-p)and glucagon]were measured.Results The fasting plasma glucose(FPG),glycated hemoglobin(HbA1c),glucagon,and C-p levels exhibited a significantly decreasing trend in T2D patients as the 25(OH)D levels increased.Next,the population was divided into two groups:abdominal obesity and non-abdominal obesity groups.After adjustment,the 25(OH)D level was found to be associated with HbA1c,glucagon,and homeostasis model assessment ofβ(HOMA-β)in the non-abdominal obesity group.There was a significant relationship between 25(OH)D and HbA1c,glucagon,HOMA-IR,baseline insulin or C-p in the abdominal obesity group.In the abdominal obesity group,the ordinary least squares(OLS)regression and quantile regression revealed that 25(OH)D was obviously associated with glucagon and fasting C-p levels.In the abdominal obesity group,the moderate analysis revealed a significant interaction effect of 25(OH)D and glucagon on C-p(P=0.0124).Furthermore,the conditional indirect effect of 25(OH)D on the glucagon/C-p ratio was significantly lower at 1 standard deviation(SD)below the mean(P=0.0002),and lower at the mean of the course of diabetes(P=0.0007).Conclusion 25(OH)D was found to be negatively correlated to glucagon and C-p in T2D patients with abdominal obesity.The 25(OH)D influenced C-p in part by influencing glucagon.The effect of 25(OH)D on the glucagon/C-p ratio in T2D patients with abdominal obesity,in terms of islet homeostasis,is influenced by the course of diabetes. 展开更多
关键词 25-hydroxyvitamin D GLUCAGON C-PEPTIDE isletαcells isletβcells type-2 diabetes
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Multi-dimensional size effects and representative elements for nonpersistent fractured rock masses: A perspective of geometric parameter distribution
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作者 Jia Wang wen zhang +4 位作者 Chun Tan Zhenbang Nie wenliang Ma Donghui Chen Qi Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2339-2354,共16页
This study takes a fractured rock mass in the Datengxia Hydropower Station,China as an example to analyze the size effects and determine the representative elementary sizes.A novel method considering geometric paramet... This study takes a fractured rock mass in the Datengxia Hydropower Station,China as an example to analyze the size effects and determine the representative elementary sizes.A novel method considering geometric parameter distributions is proposed in this work.The proposed method can quickly and simply determine the size effects and representative elementary sizes.Specifically,geometric parameter distributions,including fracture frequency,size and orientation,are generated on the basis of the Bernoulli trial and Monte Carlo simulation.The distributions are assessed using the coefficient of variation(CV),and the acceptable variations for CV(5%,10%and 20%)are used to determine representative elementary sizes.Generally,the representative element of rock masses is the representative elementary volume(REV).The present study extends the representative element to other dimensions,i.e.representative elementary length(REL)and representative elementary area(REA)for one and two dimensions,respectively.REL and REA are useful in studying the size effects of one-(1D)and twodimensional(2D)characteristics of rock masses.The relationships among multi-dimensional representative elementary sizes are established.The representative elementary sizes reduce with the increase in the dimensions,and REA and REV can be deduced by REL.Therefore,the proposed method can quickly and simply determine REL and further estimate REA and REV,which considerably improves the efficiency of rock mass analysis. 展开更多
关键词 Size effect Discrete fracture network(DFN) Stochastic mathematics ANISOTROPY Coefficient of variation(CV)
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Cryptotanshinone induces apoptosis of activated hepatic stellate cells via modulating endoplasmic reticulum stress
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作者 Xiao-Xue Hou Yu-wen Li +7 位作者 Jia-Li Song wen zhang Rui Liu Hui Yuan Tian-Tong Feng Zheng-Yi Jiang wen-Ting Li Chuan-Long Zhu 《World Journal of Gastroenterology》 SCIE CAS 2023年第17期2616-2627,共12页
BACKGROUND Cryptotanshinone(CPT)has wide biological functions,including anti-oxidative,antifibrosis,and anti-inflammatory properties.However,the effect of CPT on hepatic fibrosis is unknown.AIM To investigate the effe... BACKGROUND Cryptotanshinone(CPT)has wide biological functions,including anti-oxidative,antifibrosis,and anti-inflammatory properties.However,the effect of CPT on hepatic fibrosis is unknown.AIM To investigate the effects of CPT treatment on hepatic fibrosis and its underlying mechanism of action.METHODS Hepatic stellate cells(HSCs)and normal hepatocytes were treated with different concentrations of CPT and salubrinal.The CCK-8 assay was used to determine cell viability.Flow cytometry was used to measure apoptosis and cell cycle arrest.Reverse transcription polymerase chain reaction(RT-PCR)and Western blot analyses were used to measure mRNA levels and protein expression of endoplasmic reticulum stress(ERS)signaling pathway related molecules,respectively.Carbon tetrachloride(CCL4)was used to induce in vivo hepatic fibrosis in mice.Mice were treated with CPT and salubrinal,and blood and liver samples were collected for histopathological examination.RESULTS We found that CPT treatment significantly reduced fibrogenesis by modulating the synthesis and degradation of the extracellular matrix in vitro.CPT inhibited cell proliferation and induced cell cycle arrest at the G2/M phase in cultured HSCs.Furthermore,we found that CPT promoted apoptosis of activated HSCs by upregulating expression of ERS markers(CHOP and GRP78)and activating ERS pathway molecules(PERK,IRE1α,and ATF4),which were inhibited by salubrinal.Inhibition of ERS by salubrinal partially eliminated the therapeutic effect of CPT in our CCL4-induced hepatic fibrosis mouse model.CONCLUSION CPT can promote apoptosis of HSCs and alleviate hepatic fibrosis through modulating the ERS pathway,which represents a promising strategy for treating hepatic fibrosis. 展开更多
关键词 Hepatic fibrosis Endoplasmic reticulum stress CRYPTOTANSHINONE Hepatic stellate cells APOPTOSIS
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Comparing effectiveness and safety of paclitaxel plus raltitrexed vs. paclitaxel alone in second-line palliative chemotherapy for metastatic gastric adenocarcinoma: A randomized phase Ⅱ clinical trial
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作者 Xiaoying Zhao Zhiyu Chen +9 位作者 Xiaowei zhang Xiaodong Zhu wen zhang Lixin Qiu Chenchen Wang Mingzhu Huang Zhe zhang wenhua Li Lei Yang Weijian Guo 《Cancer Biology & Medicine》 SCIE CAS CSCD 2023年第9期682-688,共7页
Objective:Paclitaxel(P)is a standard second-line chemotherapy in the treatment of advanced gastric cancer.This study compared the clinical outcome of a paclitaxel plus raltitrexed(RP)regimen as second-line treatment i... Objective:Paclitaxel(P)is a standard second-line chemotherapy in the treatment of advanced gastric cancer.This study compared the clinical outcome of a paclitaxel plus raltitrexed(RP)regimen as second-line treatment in metastatic gastric cancer(MGC)patients.Methods:An open,randomized,multi-center phase Ⅱ clinical trial was conducted involving 148 patients who were randomly assigned and treated with RP[raltitrexed(3 mg/m^(2)on day 1)and paclitaxel(135 mg/m^(2)on day 1 every 3 weeks)]or P[paclitaxel(135 mg/m^(2)on day 1 every 3 weeks)]as 2nd-line chemotherapy.The primary endpoint was progression-free survival(PFS).The secondary endpoints were the overall response rate(ORR),overall survival(OS),and safety.Results:PFS had a tendency to be prolonged with RP compared to P(2.7 months vs.1.7 months;P=0.148).OS was also prolonged with RP compared to P(10.2 months vs.6.1 months;P=0.140).The ORR was equal in the RP and P groups(6.8%and 4.0%;P=0.72).The disease control rate(DCR)in the RP and P groups was 56.2%and 36.0%,respectively.Grade 3-4 treatment-related adverse events occurred in 36.2%(RP)and 28.2%(P)of patients.Frequent grade 3-4 toxicities for RP and P were neutropenia(11.0%and 4.0%),anemia(1.4%and 4.0%),and thrombocytopenia(1.4%and 5.3%),and all grades of peripheral neurotoxicity(12.3%vs.17.3%).All grades of hepatic toxicity were demonstrated for the RP and P groups based on elevated aminotransferase levels(27.4%and 14.1%).Subgroup analysis shows if MGC was combined with ascites or peritoneal involvement,the OS of the RP regimen was longer(P=0.05).Conclusions:Second-line palliative chemotherapy with RP was shown to prolong the PFS and OS,especially among patients with ascites or peritoneal involvement,which warrants confirmation using larger sample studies. 展开更多
关键词 Gastric adenocarcinoma RALTITREXED PACLITAXEL second-line palliative chemotherapy
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