Results 11 to 20 of about 261,599 (153)
Ultrasound in Obstetrics &Gynecology, Volume 61, Issue 3, Page 310-324, March 2023., 2023 ABSTRACT Objective To evaluate the diagnostic accuracy of different ultrasound signs for diagnosing adnexal torsion, using surgery as the reference standard. Methods This was a systematic review and meta‐analysis of studies published between January 1990 and November 2021 evaluating ovarian edema, adnexal mass, ovarian Doppler flow findings, the ...
I. Garde +8 more
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Evident but context‐dependent mortality of fish passing hydroelectric turbines
Conservation Biology, Volume 36, Issue 3, June 2022., 2022 Abstract Globally, policies aiming for conservation of species, free‐flowing rivers, and promotion of hydroelectricity as renewable energy and as a means to decarbonize energy systems generate trade‐offs between protecting freshwater fauna and development of hydropower. Hydroelectric turbines put fish at risk of severe injury during passage. Therefore,
Johannes Radinger +2 more
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Zhejiang Daxue xuebao. Lixue ban, 2004 1999年6月下旬长江中下游有一次维持时间较长的梅雨锋低涡过程，采用90-30-10 km的中尺度数值模拟资料，对6月28〜30日这一过程中两个不同尺度的低涡（中-α涡和中-β涡）进行分析：通过代表性空气质点的轨迹和物理属性个别变化的计算，揭示构成低涡的三维气流结构.结果表明：1）构成中-α涡的气流为低层西北半部干冷的东至东北气流；中低层东南象限暖湿的西南气流及高层西西北气流. 2）中-α涡南侧的西北气流在幕阜山背风坡这一有利的地形条件下与西南气流辐合，促使了中-β涡的生成.
ZHANGZhi-ying(章志英)
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Analysis of mechanism of low vortex propagated easterly(一次低涡东移机制的分析)
Zhejiang Daxue xuebao. Lixue ban, 2002 对1999年6月25日到29日发生在长江中下游流域的低涡活动进行中尺度四维同化模拟,分析发现低涡在形成后,前期高能舌未东伸,高空辐散中心与低涡中心重合或略偏后于低涡中心,低涡不东移.当高空急流中心东跃,高低空急流开始耦合时,低涡开始东移,当低涡移到高低空急流的耦合区时,低涡东移并强烈发展.
WUHui-feng(邬惠峰), GAOKun(高坤)
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Zhejiang Daxue xuebao. Lixue ban, 2003 1998年7月下旬长江中下游发生罕见的特大洪涝灾害.分析认为低空急流在7月20日10Z突然加强,在四川盆地东北侧引起低层强辐合是西南低涡得以发展的重要原因;低空急流加强引起的低层强辐合产生的潜热释放,导致中层位涡的增加,使得低涡十分深厚;低空急流在21~23日的另两次加强在西南低涡的南部引起的眠层强辐合,弥补了低涡由于低层摩擦引起的旋转减弱,使低涡长期稳定维持.
XUYa-mei(徐亚梅)
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Zhejiang Daxue xuebao. Lixue ban, 2018 通过对2009年6月5日一例皖北强灾害天气过程的中尺度分析，发现底层大气中存在西南气流的中尺度汇合线，在汇合线附近、基本西南气流的流场环境下，隐含着中尺度涡旋扰动.利用Shuman-Shapiro平滑滤波方案对日本中尺度再分析资料进行处理，揭示了滤波后出现的中尺度涡旋扰动，该涡旋扰动对应边界层中尺度辐合区和辐合中心，以及气流的最强上升支.这些中尺度扰动特征与之后初始对流回波单体的发生有较好的对应关系，说明中尺度扰动涡旋中心附近及东侧易发生对流，或者扰动涡旋率先触发了对流.
ZHANGYuanzhi(章元直) +3 more
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Zhejiang Daxue xuebao. Lixue ban, 2005 对具有偏北移动分量的东海热带气旋路径折向时的环境环流的参数变化、动力结构及涡度收支等合成分析表明：当热带气旋环境环流的总变化为东风分量增大或由于动力变化产生向左的合力或涡度变化使热带气旋强度减弱时将导致热带气旋移动路径左折；当环境环流总变化为西风分量增大或动力变化产生向右的合力或涡度变化使热带气旋强度增强时将导致移动路径右折；当合力状况少变，涡度变化不足以改变热带气旋强度时，内力与环境外力平衡维持，热带气旋的移动路径不发生折向.
ZHONGYuan(钟元), YUHui(余晖)
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Kongjian kexue xuebao已有研究发现金星磁尾的太阳风氢离子(H+)和金星电离层氧离子(O+)存在大尺度涡流结构, 该涡流从磁尾望向星球是逆时针的. 为了确定该涡流的存在性, 利用金星快车等离子体和高能原子分析仪(Analyzer of Space Plasmas and Energetic Atoms on Venus, ASPERA-4)的Fedorov矫正数据, 分别在金星公转轨道坐标系(VSO)和太阳风电场坐标系(VSE)下对磁尾等离子体流进行了统计分析.
柴 立晖, 郭 梦丹, 唐 晓谆
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The Two Faces of Introgression in Conservation Biology 基因渗入在保育生物学中的双重面貌
Integrative Conservation, Volume 4, Issue 3, Page 339-344, September 2025.Conservation biologist need to take into account the various aspects of introgression in their attempts to protect the species integrity and evolutionary potential of threatened species. To do so, they have to overcome the bias created by the Mayrian species concept that considers species as having distinct gene pools.
Harald Schneider, Charles H. Cannon
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Ultrasound in Obstetrics &Gynecology, Volume 64, Issue 5, Page 661-668, November 2024.ABSTRACT Objective To determine the diagnostic accuracy of virtual autopsy using whole‐body postmortem ultra‐high field magnetic resonance imaging (MRI) at 7 Tesla (T), using a short T2‐weighted imaging (T2‐WI) protocol, compared with classical autopsy, for detecting structural abnormalities in small second‐trimester fetuses. Methods Thirty consecutive
A. Staicu +11 more
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