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Lineaperpetua gen.nov.:a new diatom genus in the Thalassiosirales supported by morphology and molecular data
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作者 Pan YU lin yang +4 位作者 Qingmin YOU John Patrick KOCIOLEK Kangyu WANG Yonghong BI Quanxi WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期277-290,共14页
Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of... Based on a combination of morphology and molecular data of ribosomal DNA genes,a new diatom genus Lineaperpetua gen.nov.Yu,You,Kociolek&Wang is described.The features that help define Lineaperpetua at the level of genus include:a tangentially undulated valve face;continuous cribra areolae on the valve interior consisting of pores arranged as strips;single rimoportula located inside the ring of marginal fultoportulae.Additionally,phylogenetic analysis based on nuclear small subunit(SSU)rDNA sequences and nuclear large subunit(LSU)rDNA gene placed the three strains of L.lacustris in a single,monophyletic clade at a considerable sequence distance from the other genera(Thalassiosira,Conticribra,Planktoniella,Shinodiscus,and other genera)belonging to Thalassiosirales.Despite the similarities with some species of Thalassiosira,Conticribra,and Spicaticribra,the suite of features found in Lineaperpetua differentiate it from these other genera.These molecular data and morphological characters suggest an affinity of the new genus to the Thalassiosiraceae. 展开更多
关键词 DIATOM MORPHOLOGY new genus PHYLOGENY TAXONOMY Thalassiosiraceae
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The Preliminary Study on Screening and Application of Phthalic Acid-Degrading Bacteria
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作者 Honghao Zhang lin yang +3 位作者 Rubing Xu Yuxiao Sun Yong yang Yanyan Li 《Advances in Microbiology》 CAS 2024年第4期226-239,共14页
Phthalic acid is a main pollutant, which is also an important reason for the continuous cropping effect of tobacco. In order to degrade the phthalic acid accumulated in the environment and relieve the obstacle effect ... Phthalic acid is a main pollutant, which is also an important reason for the continuous cropping effect of tobacco. In order to degrade the phthalic acid accumulated in the environment and relieve the obstacle effect of tobacco continuous cropping caused by the accumulation of phthalic acid in the soil. In this study, phthalate degrading bacteria B3 is screened from continuous cropping tobacco soil. The results of biochemical identification and 16sDNA comparison show that the homology between degrading bacterium B3 and Enterobacter sp. is 99%. At the same time, the growth of Enterobacter hormaechei subsp. B3 and the degradation of phthalic acid under different environmental conditions are studied. The results show that the environment with a temperature of 30˚C, PH of 7, and inoculation amount of not less than 1.2%, which is the optimal growth conditions for Enterobacter sp. B3. In an environment with a concentration of phthalic acid not exceeding 500 mg/L, Enterobacter sp. B3 has a better effect on phthalic acid degradation, and the degradation rate can reach 77% in 7 d. The results of indoor potting experiments on tobacco show that the degradation rate of phthalic acid by Enterobacter B3 in the soil is about 45%, which can reduce the inhibitory effect of phthalic acid on the growth of tobacco seedlings. This study enriches the microbial resources for degrading phthalic acid and provides a theoretical basis for alleviating tobacco continuous cropping obstacles. 展开更多
关键词 Phthalic Acid Degrading Bacteria Rhizosphere Soil
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渗流作用下粗粒土冻结壁交圈规律及预测模型探索
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作者 刘爽 李晓康 +3 位作者 李旭 聂雯 林旸 盛志刚 《冰川冻土》 CSCD 2024年第1期247-259,共13页
由于渗流作用下的冻结壁发育规律不明等原因,部分冻结法施工工程依靠人工经验,缺乏科学的预测模型,与精准化设计和控制还有很长的距离。为探索渗流作用下冻结法施工中粗粒土层冻结壁的演化规律,本文首先建立冻结法施工数值模型,并通过... 由于渗流作用下的冻结壁发育规律不明等原因,部分冻结法施工工程依靠人工经验,缺乏科学的预测模型,与精准化设计和控制还有很长的距离。为探索渗流作用下冻结法施工中粗粒土层冻结壁的演化规律,本文首先建立冻结法施工数值模型,并通过室内模型试验反演验证所建立模型的有效性和适用性。之后,考虑渗流速度、冻结管间距、环境温度、含水率和导热系数等五个因素,开展冻结壁形成正交数值试验,确定冻结壁交圈时间和厚度的主控因素。最后,通过数值模拟研究主控因素作用下冻结壁的发育和演化规律。基于结果建立临界流速、冻结壁厚度、冻结壁交圈时间的预测模型,给出冻结法施工参数的选择方案。结果表明,建立的冻土水热相变耦合模型可有效模拟渗流条件下土体冻结过程,能够满足冻结壁发育过程计算分析的需要。基于正交数值试验结果发现,渗流速度对冻结壁厚度和交圈时间的贡献百分比分别为78%和52%,是影响冻结壁能否交圈和最终厚度的主控因素。当渗流速度超过一定阈值时,冻结壁无法交圈。本文将这一阈值定义为冻结法施工中的临界流速。当冻结壁能够交圈,其最终形成的冻结壁厚度也主要由渗流速度决定,二者呈负指数函数关系。冻结管间距对冻结壁最终厚度影响不大,但是对冻结壁交圈时间影响较大,它们之间存在负指数函数关系。本文给出了0~6 m·d^(-1)条件下的临界流速、冻结壁厚度、冻结壁交圈时间计算模型,它们可为粗粒土地层的冻结法施工参数选择和施工工艺设计提供理论指导。 展开更多
关键词 人工冻结 粗粒土 温度场 数值模拟 水热耦合
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基于“新医科”背景下的新型呼吸内科专业人才培养模式探讨
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作者 杨晓东 侯靖诗 +4 位作者 林杨 刘明月 李树民 马雪梅 孙云晖 《全科医学临床与教育》 2024年第3期193-195,共3页
2018年8月,中共中央、国务院印发关于新时代教育改革发展的重要文件,首次正式提出“新医科”概念[1]。2020年,国务院在关于“新医科”的建设中强调指出需优化医学人才培养的结构,全力提升院校医学人才培养质量,完善住院医师培训内容和... 2018年8月,中共中央、国务院印发关于新时代教育改革发展的重要文件,首次正式提出“新医科”概念[1]。2020年,国务院在关于“新医科”的建设中强调指出需优化医学人才培养的结构,全力提升院校医学人才培养质量,完善住院医师培训内容和深化继续医学教育改革,重视教育创新发展[2]。呼吸内科学作为医学类三级学科,在临床教育工作的开展中占据很重要的一部分,现代呼吸内科教育将关注点集中于如何将实践课程和理论课程恰如其分地融合并运用于临床教学。 展开更多
关键词 新时代教育 实践课程 医学类 继续医学教育 住院医师培训 三级学科 医学人才培养 呼吸内科
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陕西省环境气象条件评估指数时空变化特征研究
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作者 苏静 孙娴 +2 位作者 胡琳 林杨 王琦 《沙漠与绿洲气象》 2024年第2期146-154,共9页
基于陕西省10地市2015—2020年PM_(2.5)浓度实况监测数据和气象条件评估指数EMI,统计分析EMI和PM_(2.5)相关性及近年EMI的时空分布特征,定量评估气象条件变化及综合治理措施对陕西环境空气质量的影响。结果表明:陕西省2015—2020年EMI... 基于陕西省10地市2015—2020年PM_(2.5)浓度实况监测数据和气象条件评估指数EMI,统计分析EMI和PM_(2.5)相关性及近年EMI的时空分布特征,定量评估气象条件变化及综合治理措施对陕西环境空气质量的影响。结果表明:陕西省2015—2020年EMI可较好地表征和评估气象条件变化导致的PM_(2.5)浓度变化。2015—2020年EMI呈线性降低趋势,气象条件持续向好。月EMI均呈明显的单谷分布特征,EMI冬半年大,夏半年小。各区域EMI总体上呈关中高、陕南次之、陕北最低的分布特点,关中中部、东部EMI最大。EMI正距平百分比高值区主要分布在关中地区,各年关中均有60%以上面积正距平,其中2016年冬季关中83.0%面积正距平,37.5%面积正距平超过100%。2020年陕西省各区域环境空气质量较2015—2019年均有明显改善,全省PM_(2.5)浓度较前5 a平均降低24.8%,全省气象条件改善使PM2.5浓度较近5 a降低16.4%,排放变化使得PM_(2.5)浓度较前5 a平均下降9.4%,可见,近年陕西省大气污染综合治理措施成果显著,环境质量明显改善。 展开更多
关键词 陕西省 细颗粒物PM_(2.5) 环境空气质量评价 气象条件评估指数(EMI) 贡献率
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外周血T淋巴细胞、IL-4及趋化因子CXCL13在神经梅毒患者中的检测意义
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作者 彭超 林阳 何俐 《分子诊断与治疗杂志》 2024年第2期251-254,259,共5页
目的分析外周血T淋巴细胞、白介素-4(IL-4)及趋化因子CXC配体13(CXCL13)水平检测在神经梅毒患者中的临床意义。方法选取2020年9月至2023年1月四川大学华西医院收治的188例梅毒患者作为研究对象,其中包括62例血清固定患者(血清固定组)及... 目的分析外周血T淋巴细胞、白介素-4(IL-4)及趋化因子CXC配体13(CXCL13)水平检测在神经梅毒患者中的临床意义。方法选取2020年9月至2023年1月四川大学华西医院收治的188例梅毒患者作为研究对象,其中包括62例血清固定患者(血清固定组)及126例神经梅毒患者(神经梅毒组)(包括无症状型31例,早期58例,晚期37例)。另选取同时期于本院门诊和体检就诊的正常健康者(对照组)80名。比较不同人群、梅毒不同病情程度患者外周血T淋巴细胞、IL-4及化因子CXCL13水平。采用受试者工作特征(ROC)曲线分析外周血T淋巴细胞、IL-4及趋化因子CXCL13联合检测对早期神经梅毒识别的诊断价值。结果CD4^(+)、CD4^(+)/CD8^(+)值:神经梅毒组<血清固定组<对照组,差异有统计学意义(P<0.05)。IL-4、CXCL13水平:神经梅毒组>血清固定组>对照组,差异有统计学意义(P<0.05)。CD4^(+)、CD4^(+)/CD8^(+)值:晚期组<早期组<无症状组,差异有统计学意义(P<0.05)。IL-4、CXCL13水平:晚期组>早期组>无症状组,差异有统计学意义(P<0.05)。ROC分析显示,外周血T淋巴细胞、IL-4及趋化因子CXCL13联合检查灵敏度为89.68%,特异度为91.11%,AUC=0.862(95%CI:0.806-0.933),均高于三指标单一检查(P<0.05)。结论外周血T淋巴细胞、IL-4及趋化因子CXCL13水平变化与神经梅毒患者病情密切联系,三者联合检测度对神经梅毒的早期识别诊断具有更好的灵敏度、特异度,在神经梅毒病情进展评估及临床指导上具有更好的应用价值。 展开更多
关键词 外周血T淋巴细胞 IL-4 趋化因子CXCL13 神经梅毒
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电沉积锌用铅基阳极服役后表面结构演变研究
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作者 袁绶章 林阳 +3 位作者 董伟 陈继园 张兴国 巢书绪 《云南冶金》 2024年第2期94-99,共6页
针对由于析氧反应的过电位对阳极氧化膜的高度依赖性,极大地影响了能耗这一问题,采用扫描电子显微镜(SEM)、能量色散光谱(EDS)、电子探针(EPMA)和X射线衍射(XRD)对Pb基阳极(阳极含量:Pb-0.5%Ag-(0.02~0.03%)Ca-(0.01~0.02%)Sr-(0.01~0.0... 针对由于析氧反应的过电位对阳极氧化膜的高度依赖性,极大地影响了能耗这一问题,采用扫描电子显微镜(SEM)、能量色散光谱(EDS)、电子探针(EPMA)和X射线衍射(XRD)对Pb基阳极(阳极含量:Pb-0.5%Ag-(0.02~0.03%)Ca-(0.01~0.02%)Sr-(0.01~0.02%)La)的表面形貌、元素分布和织构进行了表征分析,结果表明:服役后的阳极板表面出现了裂纹和大量空洞。同时还观察了阳极泥的形成可能会导致阳极表面的钝化,影响了其电化学性能。 展开更多
关键词 电沉积 铅基阳极 服役性能 表面结构
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Ochratoxin A induces abnormal tryptophan metabolism in the intestine and liver to activate AMPK signaling pathway
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作者 Weiqing Ma yang Fu +8 位作者 Shanshan Zhu Daiyang Xia Shuangshuang Zhai Deqin Xiao Yongwen Zhu Michel Dione Lukuyu Ben lin yang Wence Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2674-2685,共12页
Background Ochratoxin A(OTA)is a mycotoxin widely present in raw food and feed materials and is mainly pro-duced by Aspergillus ochraceus and Penicillium verrucosum.Our previous study showed that OTA principally induc... Background Ochratoxin A(OTA)is a mycotoxin widely present in raw food and feed materials and is mainly pro-duced by Aspergillus ochraceus and Penicillium verrucosum.Our previous study showed that OTA principally induces liver inflammation by causing intestinal flora disorder,especially Bacteroides plebeius(B.plebeius)overgrowth.However,whether OTA or B.plebeius alteration leads to abnormal tryptophan-related metabolism in the intestine and liver is largely unknown.This study aimed to elucidate the metabolic changes in the intestine and liver induced by OTA and the tryptophan-related metabolic pathway in the liver.Materials and methods A total of 30 healthy 1-day-old male Cherry Valley ducks were randomly divided into 2 groups.The control group was given 0.1 mol/L NaHCO3 solution,and the OTA group was given 235μg/kg body weight OTA for 14 consecutive days.Tryptophan metabolites were determined by intestinal chyme metabolomics and liver tryptophan-targeted metabolomics.AMPK-related signaling pathway factors were analyzed by Western blot-ting and mRNA expression.Results Metabolomic analysis of the intestinal chyme showed that OTA treatment resulted in a decrease in intesti-nal nicotinuric acid levels,the downstream product of tryptophan metabolism,which were significantly negatively correlated with B.plebeius abundance.In contrast,OTA induced a significant increase in indole-3-acetamide levels,which were positively correlated with B.plebeius abundance.Simultaneously,OTA decreased the levels of ATP,NAD+and dipeptidase in the liver.Liver tryptophan metabolomics analysis showed that OTA inhibited the kynurenine metabolic pathway and reduced the levels of kynurenine,anthranilic acid and nicotinic acid.Moreover,OTA increased the phosphorylation of AMPK protein and decreased the phosphorylation of mTOR protein.Conclusion OTA decreased the level of nicotinuric acid in the intestinal tract,which was negatively correlated with B.plebeius abundance.The abnormal metabolism of tryptophan led to a deficiency of NAD+and ATP in the liver,which in turn activated the AMPK signaling pathway.Our results provide new insights into the toxic mechanism of OTA,and tryptophan metabolism might be a target for prevention and treatment. 展开更多
关键词 AMPK Metabolomics Ochratoxin A Tryptophan metabolism
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Deltonin enhances gastric carcinoma cell apoptosis and chemosensitivity to cisplatin via inhibiting PI3K/AKT/mTOR and MAPK signaling
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作者 lin yang Ya-Nan Liu +1 位作者 Yi Gu Qi Guo 《World Journal of Gastrointestinal Oncology》 SCIE 2023年第10期1739-1755,共17页
BACKGROUND As an active ingredient derived from Dioscorea zingiberensis C.H.Wright,deltonin has been reported to show anti-cancer effects in a variety of malignancies.AIM To investigate the role and mechanism of actio... BACKGROUND As an active ingredient derived from Dioscorea zingiberensis C.H.Wright,deltonin has been reported to show anti-cancer effects in a variety of malignancies.AIM To investigate the role and mechanism of action of deltonin in promoting gastric carcinoma(GC)cell apoptosis and chemosensitivity to cisplatin.METHODS The GC cell lines AGS,HGC-27,and MKN-45 were treated with deltonin and then subjected to flow cytometry and 3-(4,5-dimethylthiazol-2-yl)-3,5-diphenyltet-razolium bromide assays for cell apoptosis and viability determination.Western blot analysis was conducted to examine alterations in the expression of apoptosis-related proteins(Bax,Bid,Bad,and Fas),DNA repair-associated proteins(Rad51 and MDM2),and phosphatidylinositol 3-kinase/protein kinase B/mammalian target of the rapamycin(PI3K/AKT/mTOR)and p38-mitogen-activated protein kinase(MAPK)axis proteins.Additionally,the influence of deltonin on GC cell chemosensitivity to cisplatin was evaluated both in vitro and in vivo.RESULTS Deltonin treatment weakened viability,enhanced apoptosis,and dampened DNA repair in GC cell lines in a dose-dependent pattern.Furthermore,deltonin mitigated PI3K,AKT,mTOR,and p38-MAPK phosphorylation.HS-173,an inhibitor of PI3K,attenuated GC cell viability and abolished deltonin inhibition of GC cell viability and PI3K/AKT/mTOR and p38-MAPK pathway activation.Deltonin also promoted the chemosensitivity of GC cells to cisplatin via repressing GC cell proliferation and growth and accelerating apoptosis.CONCLUSION Deltonin can boost the chemosensitivity of GC cells to cisplatin via inactivating p38-MAPK and PI3K/AKT/mTOR signaling. 展开更多
关键词 Deltonin Gastric carcinoma CISPLATIN Apoptosis Chemotherapy Axis
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自主水下机器人布放回收技术综述
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作者 孟令帅 李明烁 +1 位作者 林扬 王智超 《无人系统技术》 2024年第1期1-19,共19页
对水下机器人布放回收这一领域的研究进行了综述并对未来研究进行了展望。首先分析了水下机器人布放回收的不同方式,主要可分为水面有人舰船、水面无人船、潜艇以及大型水下机器人布放回收方式。接着举出不同回收方式的国内外例证并对... 对水下机器人布放回收这一领域的研究进行了综述并对未来研究进行了展望。首先分析了水下机器人布放回收的不同方式,主要可分为水面有人舰船、水面无人船、潜艇以及大型水下机器人布放回收方式。接着举出不同回收方式的国内外例证并对其优缺点进行总结。随后探讨和分析了实现布放回收所需的关键技术,包括自主对接技术、定位引导技术、锁紧定位技术及对接回收策略,并对技术现状及装备进行举例分析。最后对水下机器人布放回收的研究方向和重点进行了展望。综述表明,水下机器人布放回收的结构和所需关键技术还需持续研究,特别需要关注的是随着布放回收技术研究的不断深入,未来水下机器人布放回收系统将向自主化、无人化、通用化发展。 展开更多
关键词 水下机器人 布放回收 导航定位 锁紧定位 对接回收策略 无人化
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注意缺陷多动障碍儿童粗大动作技能与执行功能发展的特点及关系
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作者 宋以玲 任园春 +4 位作者 朱飞龙 匡冬青 曹庆久 林杨 王芳 《中国康复理论与实践》 CSCD 北大核心 2024年第1期1-9,共9页
目的探讨学龄期注意缺陷多动障碍(ADHD)儿童的粗大动作技能和执行功能的发展特点及其相关关系。方法2020年11月至2021年5月于北京大学第六医院和北京市海淀区万泉小学招募90例ADHD儿童,从该小学另募集年龄和性别匹配的正常发育儿童90例... 目的探讨学龄期注意缺陷多动障碍(ADHD)儿童的粗大动作技能和执行功能的发展特点及其相关关系。方法2020年11月至2021年5月于北京大学第六医院和北京市海淀区万泉小学招募90例ADHD儿童,从该小学另募集年龄和性别匹配的正常发育儿童90例。采用儿童粗大动作发展测试量表第三版(TGMD-3)评估儿童的粗大动作技能,采用Stroop色词测验(SCWT)、Rey-Osterrich复杂图形测验(ROCFT)、连线测验(TMT)分别评估儿童的抑制控制、工作记忆和认知灵活性。结果ADHD儿童TGMD-3得分显著低于正常儿童(t=-6.275,P<0.001),SCWT、ROCFT、TMT测试结果均差于正常儿童(|t|≥1.986,P≤0.05)。ADHD儿童的TGMD-3得分与字义反应时(r=-0.261)、字义错误数(r=-0.404)、颜色错误数(r=-0.326)呈负相关(P<0.05),与延时结构记忆得分(r=0.228)呈正相关(P<0.05),与TMT-A反应时(r=-0.255)、TMT-A错误数(r=-0.329)、TMT-B反应时(r=-0.214)、TMT-B错误数(r=-0.474)呈负相关(P<0.05)。分层线性回归分析显示,ADHD儿童的TGMD-3得分仅对抑制控制和认知灵活性的测试结果具有预测作用(P<0.05),解释率分别为8.7%和22.5%。结论ADHD儿童的粗大动作技能和执行功能均存在发育滞后,且两者之间有一定关联,其中,粗大动作技能水平可在一定程度上影响抑制控制和认知灵活性的发展。 展开更多
关键词 注意缺陷多动障碍 粗大动作技能 执行功能 动作发展 儿童
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腹腔镜腹部会阴切除术后会阴疝1例及文献复习
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作者 梁书斌 林洋 +1 位作者 余翔 吕忠船 《中国现代普通外科进展》 CAS 2024年第2期166-168,共3页
会阴疝是腹内脏器通过骨盆底缺陷突出[1]。病因可以是先天性的,也可以是医源性的,通常是腹部会阴切除术、盆腔切除术和会阴前列腺切除术等骨盆手术的并发症。第1例直肠癌切除术后会阴疝在1939年由约曼[2]报告。腹部会阴切除术后会阴疝... 会阴疝是腹内脏器通过骨盆底缺陷突出[1]。病因可以是先天性的,也可以是医源性的,通常是腹部会阴切除术、盆腔切除术和会阴前列腺切除术等骨盆手术的并发症。第1例直肠癌切除术后会阴疝在1939年由约曼[2]报告。腹部会阴切除术后会阴疝的发病率报道不一,一项近十年的长期随访结果显示其发病率为0.8%~12.0%[3]。临床通常表现为会阴部隆起、疼痛、不适,部分病例伴有肠梗阻。本文报告1例既往行两次腹腔镜手术的会阴疝患者。 展开更多
关键词 会阴疝 腹腔镜
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煤矿井下钻探远程支持技术及其应用前瞻
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作者 杨轶 田宏亮 +4 位作者 王力 陈洪岩 李浩 林阳 郑司建 《煤炭技术》 CAS 2024年第2期243-248,共6页
为提升钻探工艺技术信息化程度,进一步提高业务水平、服务效率和企业管理水平,提出以煤矿井下钻探技术为理论支撑,基于网络有线、无线传输等建构煤矿井下钻探技术远程支持服务体系,开发出基于该远程支持服务体系的煤矿井下钻探技术远程... 为提升钻探工艺技术信息化程度,进一步提高业务水平、服务效率和企业管理水平,提出以煤矿井下钻探技术为理论支撑,基于网络有线、无线传输等建构煤矿井下钻探技术远程支持服务体系,开发出基于该远程支持服务体系的煤矿井下钻探技术远程服务平台系统。平台的功能实现由5个模块组成,包括慕课视频点播模块、远程故障维修模块、远程技术支持模块、消息推送模块、信息安全模块。通过基于“端对端”的钻探技术标准化培训平台和基于浏览器/B/S架构的钻探技术装备远程指导系统,为施工现场提供了故障诊断、技术查询、可视化维修等技术支持,使煤矿井下钻探技术服务更高效、更及时,有力提高了服务效率,降低了人工成本,更有效地提升了钻探工艺服务信息化程度,为钻探设备的智能化发展赋能。 展开更多
关键词 资源平台 远程服务 钻探技术 模块构建 在线指导
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基于改进TOPSIS的石化装置实时状态评估
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作者 林扬 杨哲 +3 位作者 袁壮 苟成冬 李传坤 王春利 《石油炼制与化工》 CAS CSCD 北大核心 2024年第3期89-96,共8页
针对石化装置运行工况数据积累量有限,难以满足装置运行状态传统评估方法数据需求的问题,提出基于改进逼近理想解法(TOPSIS)的状态评估方法,避免了对装置历史运行数据的依赖。该基于改进TOPSIS的评估方法,首先根据现场专家经验和工艺卡... 针对石化装置运行工况数据积累量有限,难以满足装置运行状态传统评估方法数据需求的问题,提出基于改进逼近理想解法(TOPSIS)的状态评估方法,避免了对装置历史运行数据的依赖。该基于改进TOPSIS的评估方法,首先根据现场专家经验和工艺卡片过程指标的控制限,确定TOPSIS的正、负理想解;然后根据装置运行参数特点,形成固定值型和固定区间型指标,并建立相应的评估标准。采用该基于改进TOPSIS的评估方法对某炼油厂催化裂化装置反应-再生系统的异常工况进行了分析,结果表明该评估方法可以实现对催化裂化装置反应-再生系统的运行状态进行量化监测。 展开更多
关键词 逼近理想解法 石化装置 状态评估 健康指数 催化裂化装置
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虾源罗伊氏黏液乳杆菌的分离鉴定及其性质研究
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作者 顾艳丽 林洋 +3 位作者 刘艳 郭小会 曹艳子 江国托 《动物营养学报》 CAS CSCD 北大核心 2024年第4期2660-2673,共14页
本试验旨筛选一株防治水产致病菌能力强的虾源乳酸菌,并对其抑制水产致病菌的性质进行研究。以健康南美白对虾的不同肠段菌群为菌株分离来源,采用CaCO 3-MRS固体培养基分离纯化乳酸菌,再通过抑菌能力试验和溶血试验复筛获得安全菌株。... 本试验旨筛选一株防治水产致病菌能力强的虾源乳酸菌,并对其抑制水产致病菌的性质进行研究。以健康南美白对虾的不同肠段菌群为菌株分离来源,采用CaCO 3-MRS固体培养基分离纯化乳酸菌,再通过抑菌能力试验和溶血试验复筛获得安全菌株。对筛选的乳酸菌菌株进行16S rRNA测序鉴定,并评价其生长特性、耐受性、抗生素敏感性及不同处理的发酵上清液对水产病原菌的抑菌能力。结果显示:对常见水产致病菌抑菌能力最强的安全菌株经16S rRNA测序鉴定为罗伊氏黏液乳杆菌SAMMRS-1G。在菌株的生长特性上,罗伊氏黏液乳杆菌SAMMRS-1G的最适培养pH为5.0,最适培养温度为39℃,4~14 h为其对数生长期;从耐受性上看,罗伊氏黏液乳杆菌SAMMRS-1G对人工胃肠液和渗透压均具有一定的耐受性,在pH 3.0条件下静置培养4 h存活率为90.7%,3.0 g/L的胆盐浓度下培养4 h存活率为85.3%,60‰高盐度条件下静置培养4 h存活率为98.7%;在不同处理对罗伊氏黏液乳杆菌SAMMRS-1G发酵上清液抑菌能力影响方面,发酵上清液对致病菌的抑菌能力为创伤弧菌>金黄色葡萄球菌>副溶血弧菌>腐败希瓦氏菌>沙门氏菌>嗜水气单胞>大肠杆菌>假交替单胞菌>溶藻弧菌>霍乱弧菌>哈维弧菌,且发酵上清液具有良好的热稳定性,蛋白酶处理后抑菌能力在原来的82%以上,具有较强的稳定性;小鼠安全性试验表明,罗伊氏黏液乳杆菌SAMMRS-1G对小鼠的生长性能和脏器指数均无负面影响。综上可知,本试验筛选出的虾源罗伊氏黏液乳杆菌SAMMRS-1G是一株耐受性好、防治水产致病菌能力强、代谢产物活性稳定、具有益生菌潜力的安全乳酸菌,可为水产养殖替抗产品的开发提供参考菌种。 展开更多
关键词 罗伊氏黏液乳杆菌 水产致病菌 抑菌能力 耐受性 代谢产物稳定
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Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults
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作者 Jingwen Liao Min Hu +4 位作者 Kellie Imm Clifton J.Holmes Jie Zhu Chao Cao lin yang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期195-203,共9页
Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investi... Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity. 展开更多
关键词 ADULTS Body fat distribution Physical activity Sitting time
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Optimizing 3d spin polarization of CoOOH by in situ Mo doping for efficient oxygen evolution reaction
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作者 Zhichao Jia yang Yuan +6 位作者 Yanxing Zhang Xiang Lyu Chenhong Liu Xiaoli yang Zhengyu Bai Haijiang Wang lin yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期236-244,共9页
Transition-metal oxyhydroxides are attractive catalysts for oxygen evolution reactions(OERs).Further studies for developing transition-metal oxyhydroxide catalysts and understanding their catalytic mechanisms will ben... Transition-metal oxyhydroxides are attractive catalysts for oxygen evolution reactions(OERs).Further studies for developing transition-metal oxyhydroxide catalysts and understanding their catalytic mechanisms will benefit their quick transition to the next catalysts.Herein,Mo-doped CoOOH was designed as a high-performance model electrocatalyst with durability for 20 h at 10 mAcm−2.Additionally,it had an overpotential of 260 mV(glassy carbon)or 215 mV(nickel foam),which was 78 mV lower than that of IrO_(2)(338 mV).In situ,Raman spectroscopy revealed the transformation process of CoOOH.Calculations using the density functional theory showed that during OER,doped Mo increased the spin-up density of states and shrank the spin-down bandgap of the 3d orbits in the reconstructed CoOOH under the electrochemical activation process,which simultaneously optimized the adsorption and electron conduction of oxygen-related intermediates on Co sites and lowered the OER overpotentials.Our research provides new insights into the methodical planning of the creation of transition-metal oxyhydroxide OER catalysts. 展开更多
关键词 ELECTROCATALYST in situ Raman Mo-doped CoOOH oxygen evolution reaction
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Construction of an immune-related gene signature for overall survival prediction and immune infiltration in gastric cancer
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作者 Xiao-Ting Ma Xiu Liu +1 位作者 Kai Ou lin yang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期919-932,共14页
BACKGROUND Treatment options for patients with gastric cancer(GC)continue to improve,but the overall prognosis is poor.The use of PD-1 inhibitors has also brought benefits to patients with advanced GC and has graduall... BACKGROUND Treatment options for patients with gastric cancer(GC)continue to improve,but the overall prognosis is poor.The use of PD-1 inhibitors has also brought benefits to patients with advanced GC and has gradually become the new standard treatment option at present,and there is an urgent need to identify valuable biomarkers to classify patients with different characteristics into subgroups.AIM To determined the effects of differentially expressed immune-related genes(DEIRGs)on the development,prognosis,tumor microenvironment(TME),and treatment response among GC patients with the expectation of providing new biomarkers for personalized treatment of GC populations.METHODS Gene expression data and clinical pathologic information were downloaded from The Cancer Genome Atlas(TCGA),and immune-related genes(IRGs)were searched from ImmPort.DEIRGs were extracted from the intersection of the differentially-expressed genes(DEGs)and IRGs lists.The enrichment pathways of key genes were obtained by analyzing the Kyoto Encyclopedia of Genes and Genomes(KEGGs)and Gene Ontology(GO)databases.To identify genes associated with prognosis,a tumor risk score model based on DEIRGs was constructed using Least Absolute Shrinkage and Selection Operator and multivariate Cox regression.The tumor risk score was divided into high-and lowrisk groups.The entire cohort was randomly divided into a 2:1 training cohort and a test cohort for internal validation to assess the feasibility of the risk model.The infiltration of immune cells was obtained using‘CIBERSORT,’and the infiltration of immune subgroups in high-and low-risk groups was analyzed.The GC immune score data were obtained and the difference in immune scores between the two groups was analyzed.RESULTS We collected 412 GC and 36 adjacent tissue samples,and identified 3627 DEGs and 1311 IRGs.A total of 482 DEIRGs were obtained.GO analysis showed that DEIRGs were mainly distributed in immunoglobulin complexes,receptor ligand activity,and signaling receptor activators.KEGG pathway analysis showed that the top three DEIRGs enrichment types were cytokine-cytokine receptors,neuroactive ligand receptor interactions,and viral protein interactions.We ultimately obtained an immune-related signature based on 10 genes,including 9 risk genes(LCN1,LEAP2,TMSB15A mRNA,DEFB126,PI15,IGHD3-16,IGLV3-22,CGB5,and GLP2R)and 1 protective gene(LGR6).Kaplan-Meier survival analysis,receiver operating characteristic curve analysis,and risk curves confirmed that the risk model had good predictive ability.Multivariate COX analysis showed that age,stage,and risk score were independent prognostic factors for patients with GC.Meanwhile,patients in the low-risk group had higher tumor mutation burden and immunophenotype,which can be used to predict the immune checkpoint inhibitor response.Both cytotoxic T lymphocyte antigen4+and programmed death 1+patients with lower risk scores were more sensitive to immunotherapy.CONCLUSION In this study a new prognostic model consisting of 10 DEIRGs was constructed based on the TME.By providing risk factor analysis and prognostic information,our risk model can provide new directions for immunotherapy in GC patients. 展开更多
关键词 Differentially expressed immune-related gene IMMUNOTHERAPY Gastric cancer Risk score
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高效液相色谱法同时测定婴幼儿配方乳粉中5种糖
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作者 刘瀛 王韵 +3 位作者 林洋 许文雅 郁蕉竹 张宏宏 《化学分析计量》 CAS 2024年第4期54-59,共6页
建立一种婴幼儿乳粉样品的简便快速处理方法,以高效液相色谱法定量检测样品中5种糖含量。样品经水充分溶解,沉淀蛋白质后,注入高效液相色谱仪进行检测。果糖、葡萄糖、蔗糖、麦芽糖和乳糖的质量浓度在1~10 mg/mL范围内线性良好,线性相... 建立一种婴幼儿乳粉样品的简便快速处理方法,以高效液相色谱法定量检测样品中5种糖含量。样品经水充分溶解,沉淀蛋白质后,注入高效液相色谱仪进行检测。果糖、葡萄糖、蔗糖、麦芽糖和乳糖的质量浓度在1~10 mg/mL范围内线性良好,线性相关系数均大于0.999,方法检出限均为0.15%,定量限均为0.45%。在1%、2%、10%的加标水平下,果糖、葡萄糖、蔗糖、麦芽糖、乳糖测定结果的相对标准偏差为0.9%~2.6%(n=6),回收率分别为96.5%~99.4%、97.0%~101.0%、98.2%~100.8%、99.6%~101.5%、95.5%~99.6%。该方法可用于婴幼儿乳粉中5种糖含量的日常检测。 展开更多
关键词 高效液相色谱法 婴幼儿乳粉 果糖 葡萄糖 蔗糖 麦芽糖 乳糖
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Diabetes and high-glucose could upregulate the expression of receptor for activated C kinase 1 in retina
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作者 Jian Tan Ang Xiao +3 位作者 lin yang Yu-lin Tao Yi Shao Qiong Zhou 《World Journal of Diabetes》 SCIE 2024年第3期519-529,共11页
BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its d... BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its damage is an important indicator of DR.Receptor for activated C kinase 1(RACK1)activates protein kinase C-ε(PKC-ε)to promote the generation of reactive oxygen species(ROS)in RPE cells,leading to apoptosis.Therefore,we hypothesize that the activation of RACK1 under hypoxic/high-glucose conditions may promote RPE cell apoptosis by modulating PKC-ε/ROS,thereby disrupting the barrier effect of the outer blood retinal barrier and contributing to the progression of DR.AIM To investigate the role and associated underlying mechanisms of RACK1 in the development of early DR.METHODS In this study,Sprague-Dawley rats and adult RPE cell line-19(ARPE-19)cells were used as in vivo and in vitro models,respectively,to explore the role of RACK1 in mediating PKC-εin early DR.Furthermore,the impact of RACK1 on apoptosis and barrier function of RPE cells was also investigated in the former model.RESULTS Streptozotocin-induced diabetic rats showed increased apoptosis and upregulated expression of RACK1 and PKC-εproteins in RPE cells following a prolonged modeling.Similarly,ARPE-19 cells exposed to high glucose and hypoxia displayed elevated mRNA and protein levels of RACK1 and PKC-ε,accompanied by an increases in ROS production,apoptosis rate,and monolayer permeability.However,silencing RACK1 significantly downregulated the expression of PKC-εand ROS,reduced cell apoptosis and permeability,and protected barrier function.CONCLUSION RACK1 plays a significant role in the development of early DR and might serve as a potential therapeutic target for DR by regulating RPE apoptosis and barrier function. 展开更多
关键词 Diabetic retinopathy Receptor for activated C kinase 1 Protein kinase C-ε Adult retinal pigment epithelium cell line-19
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