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Hepatitis B Virus Screening Patterns amongst Physicians in Hawaii: Changes in a Decade
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作者 Chuong T. Tran Krista K. Kiyosaki Linda L. Wong 《Open Journal of Gastroenterology》 2015年第10期139-145,共7页
Purpose: Hawaii had the highest incidence of liver cancer in the US and had a unique patient population with many immigrants from the Pacific and Asia where Hepatitis B virus (HBV) was endemic. HBV screening in high r... Purpose: Hawaii had the highest incidence of liver cancer in the US and had a unique patient population with many immigrants from the Pacific and Asia where Hepatitis B virus (HBV) was endemic. HBV screening in high risk populations was a recommended measure of preventative medicine, thus we sought to examine physician screening patterns for HBV in Hawaii. Methods: We retrospectively analyzed billing claims from 1999 to 2009 from the largest healthcare coverage provider in the state of Hawaii. We identified all patients (>18 years) who underwent HBV screening based on Current Procedural Terminology (CPT) billing codes. We collected data on age, gender and specialty of physicians ordering the screening tests. Analysis was done in 2013 and 2014. Results: Of an estimated 700,000 covered lives, 125,576 patients underwent HBV screening. We stratified the patients into two eras from 1999-2004 (N = 52,245) and 2005-2009 (N = 73,331) to examine temporal trends. In the first era, 30,975 women (59.3%) underwent HBV screening, compared to 49,950 women (69.1%) screened in the 2005-2009 era. There absolute number of tests increased, but the proportion done by primary care MDs decreased from 55.6% to 44.9%. OB/GYN screened 15.6% in the early era and 26.9% in later era. Conclusions: There was an increase in women aged 18 - 40 years screened in the 2005-2009 era compared to 1999-2004, most likely due to OB/GYN physicians’ screening of prenatal women. Physician education on HBV vaccination/treatment or appropriate referral should include OB/GYN as well as primary care physicians. 展开更多
关键词 CPT Codes HEPATITIS B HBV SCREENING PATTERNS Hawaii
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Genotype and phylogenetic characterization of hepatitis B virus among multi-ethnic cohort in Hawaii 被引量:2
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作者 Mayumi Sakurai Fuminaka Sugauchi +6 位作者 Naoky Tsai Seiji Suzuki Izumi Hasegawa Kei Fujiwara Etsuro Orito Ryuzo Ueda Masashi Mizokami 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第15期2218-2222,共5页
AIM: Hepatitis B virus (HBV) genomes in carriers from Hawaii have not been evaluated previously. The aim of thepresent study was to evaluate the distribution of HBV genotypes and their clinical relevance in Hawaii.MET... AIM: Hepatitis B virus (HBV) genomes in carriers from Hawaii have not been evaluated previously. The aim of thepresent study was to evaluate the distribution of HBV genotypes and their clinical relevance in Hawaii.METHODS: Genotyping of HBV among 61 multi-ethnicc arriers in Hawaii was performed by genetic methods.Three complete genomes and 61 core promoter/precore regions of HBV were sequenced directly.RESULTS: HBV genotype distribution among the 61 carderswas 23.0% for genotype A, 14.7% for genotype B and 62.3% for genotype C. Genotypes A, B and C were obtained from the carriers whose ethnicities were Filipino and Caucasian,Southeast Asian, and various Asian and Micronesian,respectively. All cases of genotype B were composed of recombinant strains with genotype C in the precore plus core region named genotype Ba. HBeAg was detected more frequently in genotype C than in genotype B (68.4% vs 33.3%, P<0.05) and basal core promoter (BCP) mutation (T1762/A1764) was more frequently found in genotype C than in genotype B. Twelve of the 38 genotype C strains possessed C at nucleotide (nt) position 1858 (C-1858).However there was no significant difference in clinical characteristics between C-1858 and T-1858 variants. Based on complete genome sequences, phylogenetic analysis revealed one patient of Micronesian ethnicity as having C1858 clustered with two isolates from Polynesia with T-1858.In addition, two strains from Asian ethnidties were clustered with known isolates in carriers from Southeast Asia.CONCLUSION: Genotypes A, B and C are predominant types among multi-ethnic HBV carriers in Hawaii, and distribution of HBV genotypes is dependent on the ethnic background of the carriers in Hawaii. 展开更多
关键词 基因型 系统描述 乙型肝炎病毒 多种部队 夏威夷 HBV 重组细胞
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Rock Magnetic Characterization of Fine Particles from Car Engines, Brake Pads and Tobacco: An Environmental Pilot Study on Oahu, Hawaii, USA
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作者 Emilio Herrero-Bervera Karl Gerstnecker +1 位作者 Vanessza Lopez Brian Swilley 《Journal of Geoscience and Environment Protection》 2020年第6期130-139,共10页
Today, it is well known that small airborne particles are very harmful to human health. For the first time in Hawaii we have conducted an environmental pilot study of fine magnetic particles on the island of Oahu, Haw... Today, it is well known that small airborne particles are very harmful to human health. For the first time in Hawaii we have conducted an environmental pilot study of fine magnetic particles on the island of Oahu, Hawaii, of particulate matter (PM) PM = 60, PM = 10, and PM = 2.5. In order to do a rock magnetic characterization we have performed low field susceptibility vs. temperature [k-T] experiments to determine the Curie points of small particles collected from exhaust pipes, as well as from brake pads of four different types of car engines using gasoline octane ratings of 87, 89, and 92. The Curie point determinations are very well defined and range from 292<span style="color:#4F4F4F;font-family:" font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span>C through 393<span style="white-space:normal;"><span style="color:#4F4F4F;font-family:" font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span></span>C and up to 660<span style="color:#4F4F4F;font-family:" font-size:14px;white-space:normal;background-color:#ffffff;"="">°</span>C. In addition, we have conducted magnetic granulometry experiments on raw tobacco, burnt tobacco ashes, as well as on automotive engine exhaust, and brake pads in question. The results of the experiments show ferro and ferrimagnetic hysteresis loops with magnetic grain sizes ranging from superparamagnetic-multidomain [SP-MD], multidomain [MD] and pseudo-single domain [PSD] shown on the modified Day et al., diagram of <a href="#ref3">Dunlop (2002)</a>. Thus far, the results we have obtained from this pilot study are in agreement with other studies conducted from cigarette ashes from Bulgaria. Our results could be correlated to the traffic-related PM in Rome, Italy where the SP fraction mainly occurs as coating of MD particles originated by localized stress in the oxidized outer shell surrounding the un-oxidized core of magnetite-like grains. All these magnetic particles have been reported to be very harmful to our human bodies (i.e. brain, lungs, heart, liver etc.). 展开更多
关键词 Particulate Matter Magnetic Minerals Magnetic Susceptibility Curie Points Magnetic Grain Sizes Cigarette Ashes TOBACCO GASOLINE Brake Pads
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On the Possibility of Obtaining Geomagnetic Volcanic Records of the Short-Term Behavior of the Laschamp and Pringle Falls Excursions from the Long Sequence of Kahuku and Ninole Hills, Big Island of Hawaii, USA
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作者 Emilio Herrero-Bervera 《Open Journal of Geology》 2021年第12期712-733,共22页
The Mauna Loa volcano of the Big Island of Hawaii offers the “ad-hoc” lava flows that have recorded the geomagnetic short-term behavior (<em>i.e.</em> excursions) at two key localities such as the younge... The Mauna Loa volcano of the Big Island of Hawaii offers the “ad-hoc” lava flows that have recorded the geomagnetic short-term behavior (<em>i.e.</em> excursions) at two key localities such as the younger Kahuku volcanic series (ca. ~41 ka) where 29 flows are exposed for detailed paleomagnetic sampling making up 102 meters of section where the uppermost flow sampled lies directly under the Pahala ash. The second sampling site is the Ninole volcanic series where 25 flows spanning 56 meters of section were also sampled from the northeast and southwest sides of the Kilohana Ridge. The most recent age estimate indicates that the Kahuku flows can correlate well with the transitional/excursional directional results obtained from both volcanic and deep-sea sediments of the global record of the Laschamp (ca. ~41 ka calendar years B.P) excursion and the Ninole flows which are associated to the also global Pringle Fall excursion (ca. 211 ± 13 ka) recorded at the type section. 展开更多
关键词 Ninole Hills Kahuku Ranch Mauna Loa Volcano Laschamp Pringle Falls Excursion
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Study of Declination, Inclination and Absolute Paleointensity of the Short-Term Geomagnetic Behavior (i.e. Cryptochron C2r.2r-1, ca. 2.46 ±0.13 Ma) Recorded at the Type Section of Halawa Valley, Koo’lau Volcano, Oahu, Hawaii, USA
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作者 Emilio Herrero-Bervera 《Journal of Geoscience and Environment Protection》 2021年第12期211-224,共14页
A novel determination of the absolute paleointensity (P.I) of 28 flows that recorded Cryptochron C2r.2r-1 (ca. 2.46 ± 0.13 Ma) using the modified Thellier-Coe method was undertaken to understand the geomagnetic e... A novel determination of the absolute paleointensity (P.I) of 28 flows that recorded Cryptochron C2r.2r-1 (ca. 2.46 ± 0.13 Ma) using the modified Thellier-Coe method was undertaken to understand the geomagnetic evolution of the paleofield during an excursion with </span><span style="font-family:"">the</span><span style="font-family:""> existence of less than 10</span><span style="font-family:""> </span><span style="font-family:"">Kyrs. The successful PI determinations along the 120-meter sequential erupted flows indicate that within the truly transitional/excursional portion of the record there is a conspicuous decrease of the PI values ranging from 20 μT to low values of about 5</span><span style="font-family:""> </span><span style="font-family:"">μT. These values are comparable to lows similar to polarity transitions of the geomagnetic field. At the base of the sequence</span><span style="font-family:"">,</span><span style="font-family:""> the record shows oscillations of the paleofied ranging from 120 μT and as low as ~10</span><span style="font-family:""> </span><span style="font-family:"">μT with very variable changes of the non-transitional/excursional paleofield. 展开更多
关键词 Absolute Paleointensity Determinations Thellier-Coe Cryotpchron
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东亚大槽和西伯利亚高压的季节内变率对冬季东亚气温的影响
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作者 李天明 丁柳丹 《大气科学学报》 CSCD 北大核心 2024年第2期184-200,共17页
基于气候态定义了西伯利亚高压指数(SH index)、东亚大槽指数(ET index)和高低压系统间的东亚经向风指数(V index),使用回归分析探究西伯利亚高压和东亚大槽在季节内尺度上对东亚地区冬季温度的影响机理,构建线性模型对冬季华南地区季... 基于气候态定义了西伯利亚高压指数(SH index)、东亚大槽指数(ET index)和高低压系统间的东亚经向风指数(V index),使用回归分析探究西伯利亚高压和东亚大槽在季节内尺度上对东亚地区冬季温度的影响机理,构建线性模型对冬季华南地区季节内尺度温度进行延伸期预报。结果表明:西伯利亚高压和东亚大槽系统变化中最显著的是季节内尺度信号;季节内尺度SH index和ET index对V index的贡献分别为82.6%和42.2%;3个指数的回归模态在对流层中层对应西北-东南向低频罗斯贝波列缓慢东南传播,低层水汽、近地面层环流、降水及2 m温度场配置良好,当西伯利亚高压深厚或东亚大槽发展时,经向风关键区北风强盛,有利于冬季高纬度地区干冷空气向东亚输送;V index对华南地区冬季季节内尺度2 m气温的有效预报时效达25 d。 展开更多
关键词 西伯利亚高压 东亚大槽 季节内尺度变率 冬季东亚气温 延伸期预报
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夏季欧亚中高纬大气ISO与欧洲阻塞频率的联系及其对极端高温事件的协同作用
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作者 温昕晟 杨双艳 +1 位作者 高铭祥 李天明 《大气科学》 CSCD 北大核心 2024年第3期1043-1058,共16页
本文利用1979~2018年NCEP逐日再分析资料,探讨了夏季欧亚中高纬地区10~30天大气季节内振荡(ISO)的时空演变及其对欧洲阻塞频率的影响,并探讨了两者对欧亚极端高温发生频率的协同作用。研究表明,欧亚中高纬10~30天大气ISO表现出东传和西... 本文利用1979~2018年NCEP逐日再分析资料,探讨了夏季欧亚中高纬地区10~30天大气季节内振荡(ISO)的时空演变及其对欧洲阻塞频率的影响,并探讨了两者对欧亚极端高温发生频率的协同作用。研究表明,欧亚中高纬10~30天大气ISO表现出东传和西传两种模态。东(西)传模态下,对流层西北—东南向倾斜的四极型(东西向分布的偶极型)准正压位势高度异常耦合温度异常同时向东南方向(向西)传播。位相合成表明,在两个模态下,中高纬低频Rossby波列在传播过程中能够显著影响欧洲阻塞的发生。东(西)传模态位相6~7(5~6)期间,欧洲阻塞发生最频繁。在东(西)传模态位相6~7(5~6)期间,欧洲西部、东欧平原、乌拉尔山以及我国东北平原(欧洲和乌拉尔山)地区分别受准正压的+-+-(+-)高度异常控制。有阻塞发生时,东传模态下,欧洲西部的正高度异常强度明显增强,乌拉尔山地区,东欧平原以及我国东北平原地区的高度异常强度均有所减弱。同时,欧洲以南出现负的高度异常;西传模态下,偶极型高度异常强度均增强,欧洲以南和我国东北平原分别出现负的和正的高度异常。可见,在两个模态阻塞频发位相下,阻塞的发生增加了欧洲和我国东北地区极端高温事件的发生频率,降低了欧洲以南和乌拉尔山地区极端高温事件的发生频率。因此,欧洲阻塞活动显著调控了欧亚中高纬地区大气ISO两个传播模态对极端高温事件的影响。 展开更多
关键词 欧亚中高纬 季节内振荡 欧洲阻塞 极端高温
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气候系统预测:基础创新和集成应用
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作者 王会军 戴永久 +6 位作者 杨崧 李天明 罗京佳 尹志聪 段明铿 周放 张艺佳 《大气科学学报》 CSCD 北大核心 2024年第2期161-172,共12页
随着全球变暖,极端天气气候事件增强,天气气候灾害造成的损失也愈发严重。当前气候预测的准确性远远不能满足社会需要,气候系统预测理论和方法面临着众多挑战性问题。为提档气候预测科学水平和准确率,由南京信息工程大学和中山大学承担... 随着全球变暖,极端天气气候事件增强,天气气候灾害造成的损失也愈发严重。当前气候预测的准确性远远不能满足社会需要,气候系统预测理论和方法面临着众多挑战性问题。为提档气候预测科学水平和准确率,由南京信息工程大学和中山大学承担的“气候系统预测研究中心”获得国家自然科学基金基础科学中心项目支持(2021年1月—2025年12月)。在该项目执行的前三年,项目团队开展了大量深入系统的研究,并取得了若干重要进展:1)揭示了气候系统的若干关键变化、驱动力和机制;2)剖析了海-陆-冰-气相互作用对我国重大极端气候事件的影响;3)在气候系统数值模式研发和预测系统集成方面取得重要进展;4)发展了延伸期-S2S-年代际的气候系统预测理论和方法。本文对这些进展作了扼要介绍,并针对气候与环境变化归因、古今气候环境研究融合、跨时空气候系统变异和极端气候、人工智能与气候科学、年代际预测和风险应对体系等关键科学问题做了展望。 展开更多
关键词 气候系统 气候预测 极端气候 海-陆-冰-气相互作用 全球变化
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A Physics-informed Deep-learning Intensity Prediction Scheme for Tropical Cyclones over the Western North Pacific 被引量:1
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作者 Yitian ZHOU Ruifen ZHAN +4 位作者 Yuqing WANG Peiyan CHEN Zhemin TAN Zhipeng XIE Xiuwen NIE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1391-1402,共12页
Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a ti... Accurate prediction of tropical cyclone(TC)intensity is challenging due to the complex physical processes involved.Here,we introduce a new TC intensity prediction scheme for the western North Pacific(WNP)based on a time-dependent theory of TC intensification,termed the energetically based dynamical system(EBDS)model,together with the use of a long short-term memory(LSTM)neural network.In time-dependent theory,TC intensity change is controlled by both the internal dynamics of the TC system and various environmental factors,expressed as environmental dynamical efficiency.The LSTM neural network is used to predict the environmental dynamical efficiency in the EBDS model trained using besttrack TC data and global reanalysis data during 1982–2017.The transfer learning and ensemble methods are used to retrain the scheme using the environmental factors predicted by the Global Forecast System(GFS)of the National Centers for Environmental Prediction during 2017–21.The predicted environmental dynamical efficiency is finally iterated into the EBDS equations to predict TC intensity.The new scheme is evaluated for TC intensity prediction using both reanalysis data and the GFS prediction data.The intensity prediction by the new scheme shows better skill than the official prediction from the China Meteorological Administration(CMA)and those by other state-of-art statistical and dynamical forecast systems,except for the 72-h forecast.Particularly at the longer lead times of 96 h and 120 h,the new scheme has smaller forecast errors,with a more than 30%improvement over the official forecasts. 展开更多
关键词 tropical cyclones western North Pacific intensity prediction EBDS LSTM
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城市人因视角下公众灾害感知时空特征及其影响因素研究 被引量:1
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作者 范雅婷 郑竹茵 +1 位作者 李越凡 范悦 《世界建筑》 2024年第7期101-107,共7页
近年来全球范围内极端天气事件频发,公众作为城市承灾的主体之一,通过微博等社交媒体表达的对灾害进程的主观感知,深刻反应并影响着应急响应和灾情发展,因此,通过城市人因的视角和方法进行公众灾害感知研究,对城市韧性提升有重大意义。... 近年来全球范围内极端天气事件频发,公众作为城市承灾的主体之一,通过微博等社交媒体表达的对灾害进程的主观感知,深刻反应并影响着应急响应和灾情发展,因此,通过城市人因的视角和方法进行公众灾害感知研究,对城市韧性提升有重大意义。本文以深圳2018年9月台风“山竹”期间的微博数据为例,分别利用LDA模型文本聚类和SnowNLP模型情感训练得到公众灾害主题感知和公众灾害情绪感知,基于DBSCAN空间聚类,归纳公众灾害感知的时空分布特征,并从物理建成环境和公众社会属性两方面探究影响公众灾害感知特征的因素。揭示极端天气下公众的灾害感知特征,及其与建成环境及社会属性之间的影响关联,为城市韧性规划设计提供指引。 展开更多
关键词 城市人因 公众灾害感知 情绪感知 建成环境 社会属性
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全龄友好社区公园的内涵辨析与建设策略——美国的经验及启示
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作者 王春彧 丁剑秋 郑远伟 《世界建筑》 2024年第8期94-100,共7页
社区公园可以带来生理、心理健康效益,是全龄友好城市建设的重要组成部分。美国在社区公园建设方面起步较早,经过多年实践已经建成了大量全龄友好社区公园项目,并逐步形成了完善的规划体系。相比之下,我国全龄友好社区公园规划尚处于初... 社区公园可以带来生理、心理健康效益,是全龄友好城市建设的重要组成部分。美国在社区公园建设方面起步较早,经过多年实践已经建成了大量全龄友好社区公园项目,并逐步形成了完善的规划体系。相比之下,我国全龄友好社区公园规划尚处于初步探索阶段,亟需借鉴国际先进经验。本文辨析全龄友好社区公园概念的内涵,梳理美国全龄友好社区公园规划体系的演进历程,并选取8个典型案例进行分析。在此基础上,总结由“前期准备—调研评估—寻求改善—方案测试”组成的实施流程,以及由“目标层—策略层—工具层”组成的建设策略体系。基于美国经验的启示,探讨我国全龄友好型社区公园的具体规划设计对策,为我国全龄友好型城市建设提供参考。 展开更多
关键词 全龄友好 社区公园 美国 城市社区 公共空间
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Effect of in ovo feeding of xylobiose and xylotriose on plasma immunoglobulin, cecal metabolites production, microbial ecology, and metabolic pathways in broiler chickens
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作者 Razib Das Pravin Mishra +1 位作者 Birendra Mishra Rajesh Jha 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1578-1589,共12页
Background Dietary supplementation of xylooligosac charides(XOS) has been found to influence gut health by manipulating cecal microbiota and producing microbe-origin metabolites.But no study investigated and compared ... Background Dietary supplementation of xylooligosac charides(XOS) has been found to influence gut health by manipulating cecal microbiota and producing microbe-origin metabolites.But no study investigated and compared the effect of in ovo feeding of xylobiose(XOS2) and xy lotriose(XOS3) in chickens.This study investigated the effect of in ovo feeding of these XOS compounds on post-hatch gut health parameters in chickens.A total of 144 fertilized chicken eggs were divided into three groups:a) non-injected control(CON),b) XOS2,and c) XOS3.On the 17^(th) embryonic day,the eggs of the XOS2 and XOS3 groups were injected with 3 mg of XOS2 and XOS3 diluted in 0.5 mL of 0.85% normal saline through the amniotic sac.After hatching,the chicks were raised for 21 d.Blood was collected on d 14 to measure plasma immunoglobulin.Cecal digests were collected for measuring short-chain fatty acids(SCFA) on d 14 and 21,and for microbial ecology and microbial metabolic pathway analyses on d 7 and 21.Results The results were considered significantly different at P<0.05.ELISA quantified plasma IgA and IgG on d 14chickens,revealing no differences among the treatments.Gas chromatography results showed no significant differences in the concentrations of cecal SCFAs on d 14 but significant differences on d 21.However;the SCFA concentrations were lower in the XOS3 than in the CON group on d 21.The cecal metagenomics data showed that the abundance of the family Clostridiaceae significantly decreased on d 7,and the abundance of the family Oscillospiraceae increased on d 21 in the XOS2 compared to the CON.There was a reduction in the relative abundance of genus Clostridium sense stricto 1 in the XOS2 compared to the CON on d 7 and the genus Ruminococcus,torques in both XOS2 and XOS3 groups compared to the CON on d 21.The XOS2 and XOS3 groups reduced the genes for chondroitin sulfate degradation Ⅰ and L-histidine degradation Ⅰpathways,which contribute to improved gut health,respectivelyc in the microbiome on d 7.In contrast,on d 21,the XOS2 and XOS3 groups enriched the thiamin salvage Ⅱ,L-isoleucine biosynthesis Ⅳ,and O-antigen building blocks biosynthesis(E. coli) pathways,which are indicative of improved gut health.Unlike the XOS3 and CON,the microbiome enriched the pathways associated with energy enhancement,including flavin biosynthesis Ⅰ,sucrose degradation Ⅲ,and Calvin-Benson-Bassham cycle pathways,in the XOS2 group on d 21.Conclusion In ovo XOS2 and XOS3 feeding promoted beneficial bacterial growth and reduced harmful bacteria at the family and genus levels.The metagenomic-based microbial metabolic pathway profiling predicted a favorable change in the availability of cecal metabolites in the XOS2 and XOS3 groups.The modulation of microbiota and metabolic pathways suggests that in ovo XOS2 and XOS3 feeding improved gut health during the post-hatch period of broilers. 展开更多
关键词 BROILER In ovo METAGENOMICS Prebiotic XYLOOLIGOSACCHARIDES
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On the Optimal Initial Inner-Core Size for Tropical Cyclone Intensification: An Idealized Numerical Study
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作者 Rong FEI Yuqing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2141-2155,共15页
Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of... Recent observational and numerical studies have revealed the dependence of the intensification rate on the inner-core size of tropical cyclones(TCs). In this study, with the initial inner-core size(i.e., the radius of maximum wind—RMW)varied from 20–180 km in idealized simulations using two different numerical models, we found a nonmonotonic dependence of the lifetime maximum intensification rate(LMIR) on the inner-core size. Namely, there is an optimal innercore size for the LMIR of a TC. Tangential wind budget analysis shows that, compared to large TCs, small TCs have large inward flux of absolute vorticity due to large absolute vorticity inside the RMW. However, small TCs also suffer from strong lateral diffusion across the eyewall, which partly offsets the positive contribution from large inward flux of absolute vorticity. These two competing processes ultimately lead to the TC with an intermediate initial inner-core size having the largest LMIR. Results from sensitivity experiments show that the optimal size varies in the range of 40–120 km and increases with higher sea surface temperature, lower latitude, larger horizontal mixing length, and weaker initial TC intensity. The 40–120 km RMW corresponds to the inner-core size most commonly found for intensifying TCs in observations, suggesting the natural selection of initial TC size for intensification. This study highlights the importance of accurate representation of TC inner-core size to TC intensity forecasts by numerical weather prediction models. 展开更多
关键词 tropical cyclones INTENSIFICATION inner-core size idealized simulations
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Embryonic thermal manipulation:a potential strategy to mitigate heat stress in broiler chickens for sustainable poultry production
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作者 Sadid Al Amaz Birendra Mishra 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第4期1347-1375,共29页
Due to high environmental temperatures and climate change, heat stress is a severe concern for poultry health and production, increasing the propensity for food insecurity. With climate change causing higher temperatu... Due to high environmental temperatures and climate change, heat stress is a severe concern for poultry health and production, increasing the propensity for food insecurity. With climate change causing higher temperatures and erratic weather patterns in recent years, poultry are increasingly vulnerable to this environmental stressor. To mitigate heat stress, nutritional, genetic, and managerial strategies have been implemented with some success. However, these strategies did not adequately and sustainably reduce the heat stress. Therefore, it is crucial to take proactive measures to mitigate the effects of heat stress on poultry, ensuring optimal production and promoting poultry well-being. Embryonic thermal manipulation(TM) involves manipulating the embryonic environment's temperature to enhance broilers' thermotolerance and growth performance. One of the most significant benefits of this approach is its cost-effectiveness and saving time associated with traditional management practices. Given its numerous advantages, embryonic TM is a promising strategy for enhancing broiler production and profitability in the poultry industry. TM increases the standard incubation temperature in the mid or late embryonic stage to induce epigenetic thermal adaption and embryonic metabolism. Therefore, this review aims to summarize the available literature and scientific evidence of the beneficial effect of pre-hatch thermal manipulation on broiler health and performance. 展开更多
关键词 BROILER EMBRYO EPIGENETICS Global warming THERMOREGULATION
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Missed Pancreaticobiliary Malignancy: The Flaw of the Expedited Cholecystectomy
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作者 Dylan S. Goto Larissa Fujii-Lau Linda L. Wong 《Surgical Science》 2024年第7期451-464,共14页
Background: Early cholecystectomy has been recommended for patients with acute cholecystitis and gallstone pancreatitis. However, patients with pancreaticobiliary malignancy may present acutely with similar symptoms. ... Background: Early cholecystectomy has been recommended for patients with acute cholecystitis and gallstone pancreatitis. However, patients with pancreaticobiliary malignancy may present acutely with similar symptoms. We hypothesize that the diagnoses of these malignancies may potentially be delayed as an unintended consequence of expedited cholecystectomies. This study reviews a cohort of patients who underwent pancreaticoduodenectomy (PD) to identify those who underwent a separate cholecystectomy before their PD. Methods: We retrospectively reviewed 162 PDs performed between 2012 and 2022. Data collected included: demographics, disease etiology and the presence of cholelithiasis. We identified patients who had a previous cholecystectomy and the time elapsed before PD as well as procedures done during the interval. We reported detailed case summaries on those patients who had a cholecystectomy within 1 year of PD. Results: In the entire cohort, mean age was 65 years, 54% were males, and 83% had a malignant reason for PD. Thirty-one patients had cholelithiasis with 23 (14%) patients having had previous cholecystectomy. Six patients had cholecystectomy within 1 year of PD. They had the following malignancies: ampullary—3, pancreas—1, cholangiocarcinoma—1 and neuroendocrine—1. Four of these patients had expedited cholecystectomy on their index hospital admission and were later found to have a periampullary malignancy with further work up. Conclusions: Pancreaticobiliary malignancies can be difficult to diagnose, and surgeons should not overlook these potential diagnoses when considering expedited cholecystectomy. Future studies in large cohorts are needed to identify high risk candidates who should undergo more detailed testing to exclude malignancy before proceeding with cholecystectomy. 展开更多
关键词 CHOLECYSTECTOMY Periampullary Malignancy Pancreas Malignancy PANCREATICODUODENECTOMY
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Effect of the Initial Vortex Structure on Intensity Change During Eyewall Replacement Cycle of Tropical Cyclones:A Numerical Study
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作者 杨昕玮 王玉清 +2 位作者 王慧 徐晶 占瑞芬 《Journal of Tropical Meteorology》 SCIE 2024年第2期106-117,共12页
This study investigates the effect of the initial tropical cyclone(TC)vortex structure on the intensity change during the eyewall replacement cycle(ERC)of TCs based on two idealized simulations using the Weather Resea... This study investigates the effect of the initial tropical cyclone(TC)vortex structure on the intensity change during the eyewall replacement cycle(ERC)of TCs based on two idealized simulations using the Weather Research and Forecasting(WRF)model.Results show that an initially smaller TC with weaker outer winds experienced a much more drastic intensity change during the ERC than an initially larger TC with stronger outer winds.It is found that an initially larger TC vortex with stronger outer winds favored the development of more active spiral rainbands outside the outer eyewall,which slowed down the contraction and intensification of the outer eyewall and thus prolonged the duration of the concentric eyewall and slow intensity evolution.In contrast,the initially smaller TC with weaker outer winds corresponded to higher inertial stability in the inner core and weaker inertial stability but stronger filamentation outside the outer eyewall.These led to stronger boundary layer inflow,stronger updraft and convection in the outer eyewall,and suppressed convective activity outside the outer eyewall.These resulted in the rapid weakening during the formation of the outer eyewall,followed by a rapid re-intensification of the TC during the ERC.Our study demonstrates that accurate initialization of the TC structure in numerical models is crucial for predicting changes in TC intensity during the ERC.Additionally,monitoring the activity of spiral rainbands outside the outer eyewall can help to improve short-term intensity forecasts for TCs experiencing ERCs. 展开更多
关键词 tropical cyclones concentric eyewall inner eyewall and outer eyewall eyewall replacement cycle intensity change
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2-甲基烯丙基的紫外光解离
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作者 Lucas Michael 覃院 +2 位作者 陈旻 孙格 张劲松 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期255-263,I0102,共10页
本文利用高里德堡态氢原子飞行时间探测技术,研究了2-甲基烯丙基自由基的3p里德堡态在解离光波长范围226~244 nm下的光解离动力学过程.2-甲基烯丙基自由基由3-氯-2-甲基-1-丙烯前体在193nm光解作用下产生.在226~244nm区间内,氢原子光解... 本文利用高里德堡态氢原子飞行时间探测技术,研究了2-甲基烯丙基自由基的3p里德堡态在解离光波长范围226~244 nm下的光解离动力学过程.2-甲基烯丙基自由基由3-氯-2-甲基-1-丙烯前体在193nm光解作用下产生.在226~244nm区间内,氢原子光解碎片谱随着波长的减小而信号强度增加。氢原子产物的飞行时间谱呈现双模结构.主要产物通道(占比~98%)的平动能峰值在~7kcal/mol,在226~244nm范围内氢原子和对应解离碎片平动能平均值为总过剩能量的(fT)~0.18,并且解离产物角分布呈各向同性.这些低平动能,角分布各向同性的产物来自经由电子激发态内转换形成的高度振动激发的热2-甲基烯丙基的统计单分子分解过程,其形成亚甲基环丙烷+氢原子,次要产物通道(占~2%)具有较大的平动能,峰值约为50kcal/mol,(fT)≈0.63且产物呈各向异性角分布(β≈-0.2).这些高平动能、各向异性的产物是非统计性的,推测是通过3p里德堡态或基态的排斥势能面部分直接失去一个氢原子生成1,3-丁二烯十氢原子. 展开更多
关键词 紫外光解离 甲基烯丙基 自由基
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CT Thresholds for Spinal Bone Mineral Attenuation to Prioritize Eligible Older Women for Osteoporosis Screening
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作者 Seo Yeon K. Orite Bryn Higuchi +1 位作者 Hyo-Chun Yoon Lana H. Gimber 《Open Journal of Radiology》 2024年第2期92-101,共10页
Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone min... Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone mineral attenuation as measured in the L1 vertebra of CT studies to the results of dual-energy x-ray absorptiometry (DEXA) studies to determine what CT attenuation thresholds might yield a reasonable combination of sensitivity and specificity for the detection of osteoporosis. The study was limited to women between the ages of 65 and 75 years who had a DEXA study and a CT that included the L1 or adjacent vertebra performed within 3 years of the DEXA study. Results: There were 1226 women in this study, of whom 452 (38%) had osteoporosis based on a T-score ≤ −2.5 by DEXA. There were 830 CT studies performed with contrast and 396 studies which were performed without contrast. There was a statistically significant difference in the mean HU of those studies performed without contrast compared to those with contrast (unenhanced mean 103 HU versus 125 HU, p < 0.001). Different CT attenuation thresholds provided the most appropriate combination of sensitivity and specificity for the detection of osteoporosis when comparing CT studies performed without or with IV contrast and when all the CT data were used in aggregate. Conclusion: Different thresholds appear necessary when using the mean CT vertebral attenuation to identify older women for preferential referral for DEXA studies. 展开更多
关键词 OSTEOPOROSIS Bone Mineral Attenuation CT Threshold
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Effects of Enteromorpha prolifera polysaccharides on growth performance,intestinal barrier function and cecal microbiota in yellow-feathered broilers under heat stress
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作者 Wenchao Liu Huimei Liu +3 位作者 Yaoyao Wang Zhongxiang Zhao Balamuralikrishnan Balasubramanian Rajesh Jha 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期344-361,共18页
Background Global warming leading to heat stress(HS)is becoming a major challenge for broiler production.This study aimed to explore the protective effects of seaweed(Enteromorpha prolifera)polysaccharides(EPS)on the ... Background Global warming leading to heat stress(HS)is becoming a major challenge for broiler production.This study aimed to explore the protective effects of seaweed(Enteromorpha prolifera)polysaccharides(EPS)on the intestinal barrier function,microbial ecology,and performance of broilers under HS.A total of 144 yellow-feathered broilers(male,56 days old)with 682.59±7.38 g were randomly assigned to 3 groups:1)TN(thermal neutral zone,23.6±1.8℃),2)HS(heat stress,33.2±1.5℃ for 10 h/d),and 3)HSE(HS+0.1%EPS).Each group contained 6 replicates with 8 broilers per replicate.The study was conducted for 4 weeks;feed intake and body weights were measured at the end of weeks 2 and 4.At the end of the feeding trial,small intestine samples were collected for histomorphology,antioxidant,secretory immunoglobulin A(s Ig A)content,apoptosis,gene and protein expression analysis;cecal contents were also collected for microbiota analysis based on 16S r DNA sequencing.Results Dietary EPS promoted the average daily gain(ADG)of broilers during 3–4 weeks of HS(P<0.05).At the end of HS on broilers,the activity of total superoxide dismutase(T-SOD),glutathione S-transferase(GST),and the content of s Ig A in jejunum were improved by EPS supplementation(P<0.05).Besides,dietary EPS reduced the epithelial cell apoptosis of jejunum and ileum in heat-stressed broilers(P<0.05).Addition of EPS in HS group broilers'diet upregulated the relative m RNA expression of Occludin,ZO-1,γ-GCLc and IL-10 of the jejunum(P<0.05),whereas downregulated the relative m RNA expression of NF-κB p65,TNF-αand IL-1βof the jejunum(P<0.05).Dietary EPS increased the protein expression of Occludin and ZO-1,whereas it reduced the protein expression of NF-κB p65 and MLCK(P<0.01)and tended to decrease the protein expression of TNF-α(P=0.094)in heat-stressed broilers.Furthermore,the proportions of Bacteroides and Oscillospira among the three groups were positively associated with jejunal apoptosis and pro-inflammatory cytokine expression(P<0.05)and negatively correlated with jejunal Occludin level(P<0.05).However,the proportions of Lactobacillus,Barnesiella,Subdoligranulum,Megasphaera,Collinsella,and Blautia among the three groups were positively related to ADG(P<0.05).Conclusions EPS can be used as a feed additive in yellow-feathered broilers.It effectively improves growth performance and alleviates HS-induced intestinal injury by relieving inflammatory damage and improving the tight junction proteins expression.These beneficial effects may be related to inhibiting NF-κB/MLCK signaling pathway activation and regulation of cecal microbiota. 展开更多
关键词 BROILERS Cecal microbiota Heat stress Intestinal barrier function Seaweed polysaccharides
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Dyslipidemia in Adults with Type 2 Diabetes in a Rural Community in Ganadougou, Mali: A Cross-Sectional Study
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作者 Abdoulaye Diawara Djibril Mamadou Coulibaly +22 位作者 Drissa Kone Mama A. Traore Drissa Konaté Dicko S. Bazi Oumar Kassogue Djeneba Sylla Fatoumata Gniné Fofana Oudou Diabaté Mariam Traore Ibrahim Antoine Nieantao Kaly Keїta Mamadou Diarra Olivia Smith Jian Li Cheickna Cisse Talib Yusuf Abbas Crystal Zheng Segun Fatumo Kassim Traore Mamadou Wele Mahamadou Diakité Seydou O. Doumbia Jeffrey G. Shaffer 《Journal of Diabetes Mellitus》 CAS 2024年第2期133-152,共20页
Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease... Dyslipidemia is a disorder where abnormally lipid concentrations circulate in the bloodstream. The disorder is common in type 2 diabetics (T2D) and is linked with T2D comorbidities, particularly cardiovascular disease. Dyslipidemia in T2D is typically characterized by elevated plasma triglyceride and low high-density lipoprotein cholesterol (HDL-C) levels. There is a significant gap in the literature regarding dyslipidemia in rural parts of Africa, where lipid profiles may not be captured through routine surveillance. This study aimed to characterize the prevalence and demo-graphic profile of dyslipidemia in T2D in the rural community of Ganadougou, Mali. We performed a cross-sectional study of 104 subjects with T2D in Ganadougou between November 2021 and March 2022. Demographic and lipid profiles were collected through cross-sectional surveys and serological analyses. The overall prevalence of dyslipidemia in T2D patients was 87.5% (91/104), which did not differ by sex (P = .368). High low-density lipoprotein cholesterol (LDL-C) was the most common lipid abnormality (78.9%, [82/104]). Dyslipidemia was associated with age and hypertension status (P = .013 and.036, respectively). High total and high LDL-C parameters were significantly associated with hypertension (P = .029 and .006, respectively). In low-resource settings such as rural Mali, there is a critical need to improve infrastructure for routine dyslipidemia screening to guide its prevention and intervention approaches. The high rates of dyslipidemia observed in Gandadougou, consistent with concomitant increases in cardiovascular diseases in Africa suggest that lipid profile assessments should be incorporated into routine medical care for T2D patients in African rural settings. 展开更多
关键词 CHOLESTEROL Cross-Sectional Study DYSLIPIDEMIA LIPIDS MALI Type 2 Diabetes
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