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Resolving impact volatilization and condensation from target rock mixing and hydrothermal overprinting within the Chicxulub impact structure

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Geoscience Frontiers 2022年第5期13卷 16-31页

作者： thomas déhais Stepan M.Chernonozhkin Pim Kaskes Sietze J.de Graaff Vinciane debaille Frank Vanhaecke Philippe Claeys Steven Goderis Analytical Environmental and Geo-ChemistryVrije Universiteit BrusselBrusselsBelgium Laboratoire G-Time UniversitécLibre de BruxellesBrusselsBelgium department of Chemistry Atomic&Mass SpectrometryGhent UniversityGhentBelgium

This work presents isotopic data for the non-traditional isotope systems Fe,Cu,and Zn on a set of Chicxulub impactites and target lithologies with the aim of better documenting the dynamic processes taking place during hypervelocity impact events,as well as those affecting impact structures during the post-impact *** focus lies on material from the recent IOdP-ICdP Expedition 364 Hole M0077A drill core obtained from the offshore Chicxulub peak *** ejecta blanket samples from the UNAM 5 and 7 cores were used to compare the crater lithologies with those outside of the impact *** datasets of bulk Fe,Cu,and Zn isotope ratios are coupled with petrographic observations and bulk major and trace element compositions to disentangle equilibrium isotope fractionation effects from kinetic *** observed Fe and Cu isotopic signatures,with δ^(56/54)Fe ranging from0.95‰to 0.58‰and δ^(65/63)Cu from0.73‰to 0.14‰,mostly reflect felsic,mafic,and carbonate target lithology mixing and secondary sulfide mineral formation,the latter associated to the extensive and long-lived(>105 years)hydrothermal system within Chicxulub *** the other hand,the stable Zn isotope ratios provide evidence for volatility-governed isotopic *** heavier Zn isotopic compositions observed for the uppermost part of the impactite sequence and a metamorphic clast(δ^(66/64)Zn of up to 0.80‰and 0.87‰,respectively)relative to most basement lithologies and impact melt rock units indicate partial vaporization of Zn,comparable to what has been observed for Cretaceous-Paleogene boundary layer sediments around the world,as well as for tektites from various strewn *** contrast to previous work,our data indicate that an isotopically light Zn reservoir(δ^(66/64)Zn down to0.49‰),of which the existence has previously been suggested based on mass balance considerations,may reside within the upper impact melt rock(UIM)*** observation is restricted to a few UIM sampl

关键词： Chicxulub impact structure Non-traditional stable isotopes Impact volatilization Impact condensation Hydrothermal alteration Target lithology mixing

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Microbial,immune and antioxidant responses of Nile tilapia with dietary nano-curcumin supplements under chronic low temperatures

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Aquaculture and Fisheries 2024年第1期9卷 57-65页

作者： Mohammed F.El Basuini Mohamed A.A.Zaki Abdelaziz M.El-hais Mohamed G.Elhanafy Emad H.El-Bilawy Amr I.Zaineldin Mohamed F.A.Abdel-Aziz Ibrahim A.Abouelsaad Ibrahim TEl-Ratel Kumbukani Mzengereza Ronick S.Shadrack Islam I.Teiba Faculty of Agriculture Tanta UniversityTanta31527Egypt King Salman International University South Sinai46618Egypt Faculty of Agriculture Alexandria UniversityAlexandria21526Egypt Animal Health Research Institute(AHRI-dOKI) Agriculture Research CenterGiza12619Egypt Fish Rearing Lab. Aquaculture DivisionNational Institute of Oceanography and FisheriesAlexandria21556Egypt Horticulture department Faculty of AgricultureDamanhour UniversityDamanhur22511Egypt department of Poultry Production Faculty of AgricultureDamietta UniversityDamietta34517Egypt Laboratory of Aquatic Animal Nutrition Faculty of FisheriesKagoshima UniversityKagoshima890-0065Japan department of Aquatic and Fisheries Science Mzuzu UniversityMzuzuPrivate Bag 201Malawi Faculty of Aquaculture and Marine Fisheries Arish UniversityArish45516Egypt

A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).Fishes(n=225;Initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in *** low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological ***,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control ***,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ***,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SOd)and glutathione peroxidase(GPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 *** addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYMC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin *** conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.

关键词： Nano curcumin Gastrointestinal microbiota Antioxidants Non-specific immune responses Temperature stress

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Synthesis and Cytotoxic Activities of Symmetrical Uvariadiamide Analogues

Synthesis and Cytotoxic Activities of Symmetrical Uvariadiam...

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中国医药教育协会成人教育委员会三届五次理事大会暨医药教育创新研究和慢病防治学术研讨会

作者： hais-Sheng Chen School of Pharmacy Second Military Medical University

Fifteen symmetrical uvariadiamide analogues were facially synthesized and evaluated for their cytotoxic *** analogues with 4-methxoy groups exhibited significant cytotoxicity against HCT116 and A549 cells,and compound 13c had an IC of 0.69μg/mL against A549 *** 4-NH analogues showed slight inhibition on the two cell *** 9b,11b and 12b from 1,4-butanediamine showed remarkable cytotoxic effect,while compounds 9a,9c,11a,11c,12a and 12c with a chain of two or six carbon atoms had feeble inhibition on the cell *** of the substituted groups and carbon chains between nitrogen atoms were important to the inhibition of uvariadiamide analogues.

关键词： Uvaria microcarpa N,N’-butane-1,4-diylbis(4-methoxybenzamide) uvariadiamide analogues cytotoxicity

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经鼻内镜岩斜坡及颞下窝肿瘤的外科治疗

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中华耳鼻咽喉头颈外科杂志 2005年第7期40卷 488-492页

作者：张秋航刘海生孔锋首都医科大学宣武医院耳鼻咽喉头颈外科 100053

目的探讨经鼻内镜手术治疗岩斜区及颞下窝肿瘤的可行性和外科手术技术。方法2002年1月至2005年2月间对17例侵犯岩斜坡或颞下窝肿瘤单独采用内镜经鼻手术入路进行了治疗,详尽阐述外科手术技术及介绍典型病例。结果17例患者中脊索瘤5例,... 详细信息

目的探讨经鼻内镜手术治疗岩斜区及颞下窝肿瘤的可行性和外科手术技术。方法2002年1月至2005年2月间对17例侵犯岩斜坡或颞下窝肿瘤单独采用内镜经鼻手术入路进行了治疗,详尽阐述外科手术技术及介绍典型病例。结果17例患者中脊索瘤5例,脑膜瘤4例,颅咽管瘤1例,神经鞘膜瘤1例,血管母细胞瘤1例,嗅神经母细胞瘤1例,恶性淋巴瘤1例,脊索肉瘤1例,腮腺癌颅底转移1例,甲状腺癌颅底转移1例。15例患者术后复查影像显示肿瘤全部被切除,2例大部分切除。所有病例随访5～43个月,良性肿瘤中有1例脊索瘤术后5个月复发,后行2次手术,其余均无复发。5例恶性肿瘤患者均随访2年以上,无复发或死亡。术后1例蛛网膜下腔出血、2例出现脑脊液鼻漏,其中1例经保守治疗痊愈、1例经2次鼻内镜手术修补成功。无颅内感染及死亡病例。结论经鼻内镜外科技术为岩斜区和颞下窝肿瘤的外科治疗提供了一种新的方法。这种入路能够简单和迅速地到达岩斜区和颞下窝,且既能够达到微侵袭目的,又能够满足全切肿瘤的要求。但需要术者熟练掌握内镜颅底解剖学、内镜手术操作及对各区域病变丰富的外科手术经验。术中应用影像导航系统将有助于识别解剖标志,使手术过程更加安全。

关键词：颞下窝肿瘤经鼻内镜外科治疗岩斜坡外科手术技术 2002年1月嗅神经母细胞瘤蛛网膜下腔出血血管母细胞瘤恶性肿瘤患者影像导航系统颅底转移 2005年神经鞘膜瘤恶性淋巴瘤大部分切除脑脊液鼻漏岩斜区手术治疗

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船用柴油机起动电磁阀性能仿真试验研究

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舰船科学技术 2023年第20期45卷 135-141页

作者：霍柏琦韩锡岭叶春阳杨多贺玉海中国人民解放军92942部队北京100161 中国人民解放军92337部队辽宁大连116023 武汉理工大学船海与能源动力工程学院湖北武汉430063 武汉理工大学船舶动力工程技术交通行业重点实验室湖北武汉430063 武汉理工大学船舶与海洋工程动力系统国家工程实验室电控分实验室湖北武汉430063

在船用发动机或核电应急柴油机起动系统中,起动电磁阀作为通、断压缩空气的关键部件。虽在其寿命周期内无需频繁启闭,但一旦工作就必须圆满完成任务,其性能直接影响到柴油机的起动性能,进而危及到整个船舶动力系统的安全。本文以某V16... 详细信息

在船用发动机或核电应急柴油机起动系统中,起动电磁阀作为通、断压缩空气的关键部件。虽在其寿命周期内无需频繁启闭,但一旦工作就必须圆满完成任务,其性能直接影响到柴油机的起动性能,进而危及到整个船舶动力系统的安全。本文以某V16型的柴油机起动电磁阀为研究对象,分析其结构和工作原理、阐述其电磁学和动力学模型的构建方法;建立Ansys Maxwell有限元仿真模型,并试验验证该模型的合理性和计算精度,开启和关闭响应时间的误差分别是2.3%和2.8%。通过起动电磁阀静态性能仿真试验,分析不同工作气隙和驱动电压对电磁力的影响规律。通过动态性能仿真试验,探讨起动电磁阀开启过程中的电流、电感、电磁力以及阀芯位移等响应时间有关的参数变化过程,研究了不同驱动电压、动阀芯行程对开启响应时间的影响,可指导起动电磁阀优化设计。

关键词：船用柴油机起动电磁阀模拟仿真

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南疆沙漠地区沥青结合料老化规律及力学性能衰变规律研究

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公路 2022年第1期67卷 8-13页

作者：韩四红刑昌柱陈久灿赵群郑传峰中交路桥南方工程有限公司北京市101121 中交路桥建设有限公司北京市101121 吉林大学建设工程学院长春市130026

结合南疆沙漠地区特殊的气候特征,进行该地区沥青结合料特殊的老化规律及沥青结合料力学性能衰变规律的研究工作。基于南疆沙漠地区不同服役阶段旧沥青混合料,通过混合料抽提试验回收该地区不同服役阶段沥青结合料中的旧沥青,采用沥青4... 详细信息

结合南疆沙漠地区特殊的气候特征,进行该地区沥青结合料特殊的老化规律及沥青结合料力学性能衰变规律的研究工作。基于南疆沙漠地区不同服役阶段旧沥青混合料,通过混合料抽提试验回收该地区不同服役阶段沥青结合料中的旧沥青,采用沥青4组分测试技术对不同服役阶段的沥青进行组分分离测试,确定南疆沙漠地区沥青老化规律。采用差示扫描量热法(dSC)、小梁弯曲试验、弯曲梁流变试验等对沥青结合料力学性能进行定量评价,确定南疆沙漠地区不同服役阶段沥青结合料的力学衰变规律。研究结果表明,南疆沙漠地区特殊的高温气候导致沥青结合料的老化进程及老化效应极其显著,同时沥青结合料的力学性能发生大幅度衰减,应该寻求相应的抑制沥青老化的技术措施保证沥青材料的耐久性能。研究中获得的该地区沥青结合料的老化规律及力学性能衰变规律,对后续该地区沥青混合料的优化设计、沥青抑制老化技术的开发等具有一定指导意义。

关键词：南疆沙漠地区沥青结合料老化规律力学性能衰变规律

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高关水库流域主汛期降雨量的预测

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价值工程 2013年第25期32卷 50-52页

作者：陈湘海徐玲贺天忠胡小梅湖北省漳河工程管理局荆门448156

依据高关水库流域1971—2011年主汛期实测降雨量资料，应用均值标准差法建立5级分级标准。针对降雨量为相依随机变量的特点，以各阶自相关系数为权重，运用马尔可夫链模型预测未来一年的时段降雨量状态，由于采用此方法得到的是一个区... 详细信息

依据高关水库流域1971—2011年主汛期实测降雨量资料，应用均值标准差法建立5级分级标准。针对降雨量为相依随机变量的特点，以各阶自相关系数为权重，运用马尔可夫链模型预测未来一年的时段降雨量状态，由于采用此方法得到的是一个区间值而不是一个确定的数值，因此，不但扩大了预测的范围，最重要的是能够很好的指导现实的工作。该方法具有直观、预测准确、计算简便的优点，为区域降雨量的中短期预测提供了新的分析途径。

关键词：自相关系数马尔可夫链降雨量变化预测高关水库流域

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正性肌力药物对猪内毒素血症的治疗作用及对肠粘膜组织氧合的影响

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世界医学杂志 1998年第12期2卷 28-34页

作者： Germ.,RJ hais.,M

目的；短时间内注射大肠杆菌多糖曾被证实可使粘膜组织氧合下降６０％，本研究旨在评价多巴胺，多巴克塞明（ｄｏｐｏｅｘａｍｉｎｅ）和多巴酚丁胺在此情况下肠粘膜组织氧合的剂量相关性影响。设计：前瞻性随机非盲研究。地点；动物实... 详细信息

目的；短时间内注射大肠杆菌多糖曾被证实可使粘膜组织氧合下降６０％，本研究旨在评价多巴胺，多巴克塞明（ｄｏｐｏｅｘａｍｉｎｅ）和多巴酚丁胺在此情况下肠粘膜组织氧合的剂量相关性影响。设计：前瞻性随机非盲研究。地点；动物实验室。对象：麻醉并被施以机械通气的家猪。方法：以２μｇ／ｋｇ的剂量２０分钟内猪的肠系膜上动脉注入大肠杆菌脂多糖，用林格液和羟基淀粉的混合输液法。

关键词：内毒素血症正性肌力药物肠粘膜氧合作用

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Attributable cost of a nosocomial infection in the intensive care unit: A prospective cohort study

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World Journal of Critical Care Medicine 2017年第1期6卷 79-84页

作者： Binila Chacko Kurien thomas Thambu david Hema Paul Lakshmanan Jeyaseelan John Victor Peter Medical ICU Division of Critical Care Christian Medical College department of Medicine Pondicherry Institute of Medical Sciences department of Medicine Ⅱ Christian Medical College Hospital Infection Control Committee Christian Medical College department of Biostatistics Christian Medical College

AIM To study the impact of hospital-acquired infections(hais) on cost and outcome from intensive care units(ICU) in India. METHOdS Adult patients(> 18 years) admitted over 1-year, to a 24-bed medical critical care unit in India, were enrolled prospectively. Treatment cost and outcome data were collected. This cost data was merged with HAI data collected prospectively by the Hospital Infection Control Committee. Only infections occurring during ICU stay were included. The impact of HAI on treatment cost and mortality was assessed. RESULTS The mean(± Sd) age of the cohort(n = 499) was42.3 ± 16.5 years. Acute physiology and chronic health evaluation-Ⅱ score was 13.9(95%CI: 13.3-14.5); 86% were ventilated. ICU and hospital length of stay were 7.8 ± 5.5 and 13.9 ± 10 d respectively. Hospital mortality was 27.9%. during ICU stay, 76(15.3%) patients developed an infection(ventilator-associated pneumonia 50; bloodstream infection 35; urinary tract infections 3), translating to 19.7 infections/1000 ICU days. When compared with those who did not develop an infection, an infection occurring during ICU stay was associated with significantly higher treatment cost [median(inter-quartile range, IQR) INR 92893(USd 1523)(IQR 57168-140286) vs INR 180469(USd 2958)(IQR 140030-237525); P d longer duration of ICU(6.7 ± 4.5 d vs 13.4 ± 7.0 d; P d hospital stay(12.4 ± 8.2 d vs 21.8 ± 13.9 d; P d infections did not impact hospital mortality(31.6% vs 27.2%; P = 0.49).CONCLUSION An infection acquired during ICU stay was associated with doubling of treatment cost and prolonged hospitalization but did not significantly increase mortality.

关键词： Attributable cost Nosocomial infection Length of stay Mortality Intensive care

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differential subcellular distribution renders HAI-2 a less effective protease inhibitor than HAI-1 in the control of extracellular matriptase proteolytic activity

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Genes & diseases 2022年第4期9卷 1049-1061页

作者： Yi-Lin Chiu Yi-Ying Wu Robert B.Barndt Yu-Wen Lin Hou-Ping Sytwo Amy Cheng Kacy Yang Khee-Siang Chan Jehng-Kang Wang Michael d.Johnson Chen-Yong Lin Lombardi Comprehensive Cancer Center Department of Oncology Georgetown UniversityWashingtonDC 20057USA department of Biochemistry National Defense Medical CenterTapei 114Chinese Taipei division of Hematology/Oncology Department of Internal MedicineTri-Service General HospitalNational Defense Medical CenterTapei 114Chinese Taipei School of Medicine National Defense Medical CenterTapei 114Chinese Taipei department of Intensive Care Medicine Chi Mei Medical CenterTainan 710Chinese Taipei

The integral membrane,Kunitz-type serine protease inhibitors HAI-1 and HAI-2,can suppress the proteolytic activity of the type 2 transmembrane serine protease matriptase with high specificity and *** levels of extracellular matriptase proteolytic activity have,however,been observed in some neoplastic B-cells with high levels of endogenous HAI-2,indicating that HAI-2 may be an ineffective matriptase inhibitor at the cellular *** different effectiveness of the hais in the control of extracellular matriptase proteolytic activity is examined *** inducing matriptase zymogen activation in the HAI Teton daudi Burkitt lymphoma cells,which naturally express matriptase with very low levels of HAI-2 and no HAI-1,nascent active matriptase was rapidly inhibited or shed as an enzymatically active *** increasing HAI-1 expression,cellular matriptase-HAI-1 complex increased,and extracellular active matriptase decreased *** HAI-2 expression,however,resulted in cellular matriptase-HAI-2 complex levels reaching a plateau,while extracellular active matriptase remained *** contrast to this differential effect,both HAI-1 and HAI-2,even at very low levels,were shown to promote the expression and cell-surface translocation of endogenous *** difference in the suppression of extracellular active matriptase by the two closely related serine protease inhibitors could result from the primarily cell surface expression of HAI-1 compared to the mainly intracellular localization of *** hais,therefore,resemble one another with respect to promoting matriptase expression and surface translocation but differ in their effectiveness in the control of extracellular matriptase enzymatic activity.

关键词： HAI-1 HAI-2 Matriptase Neoplastic B-cells Proteolytic activity

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