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91.
MARCO BARON TOALDO ALESSIA DIANA MARIA MORINI MARIO CIPONE 《Veterinary radiology & ultrasound》2010,51(5):512-515
An 11‐year‐old, male, Pekinese was examined because of a sporadic, nonresponsive, nonproductive cough. Radiographically there was cardiomegaly and a soft tissue mass in the cranial mediastinum. Echocardiographically, chronic degenerative valvular disease was diagnosed. Furthermore, a large anechoic structure located cranial to the right atrium was detected. Computed tomography was performed to define the mediastinal mass and a right auricle aneurysm was diagnosed. The dog died suddenly 1 day after the diagnostic imaging procedures. At necropsy, a right auricular aneurysm without discontinuity of the pericardial sac was confirmed. Intrapericardial right auricular aneurysm should be included in the differential diagnoses of cranial mediastinal masses. 相似文献
92.
湖南隆回一次大暴雨天气过程综合分析 总被引:1,自引:0,他引:1
吕校华 《湖南农业大学学报(自然科学版)》2010,36(3):349-355
利用常规探空资料、地面观测资料、自动气象站资料及水文雨量点资料、T213数值预报资料和卫星云图等,对湖南隆回2006年6月25日大暴雨天气过程进行综合分析.结果表明:暴雨区中上升运动和水汽辐合均大于周围区域,中低层为对流不稳定层结;大气层结的强烈不稳定,强烈的垂直运动,是形成暴雨的主要因素;700hPa的水汽来自孟加拉湾和南海,850hPa和500hPa的水汽来自南海;大暴雨发生前,低层有较强的水平能量输送和能量积聚,同时整个暴雨区的大气运动由下沉运动转变为上升运动;中低层Q矢量的辐合和大暴雨的落区、发生时段有较好的对应关系;低层正涡度、高层负涡度与低层强辐合、高层强辐散一致;"抽吸作用"和反馈作用加强低空辐合,促使暴雨发展. 相似文献
93.
Dothistroma needle blight: an emerging epidemic caused by Dothistroma septosporum in Colombia
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Plantation forestry in Colombia is based mainly on non‐native species of Pinus and Eucalyptus. Since 2008, a disease with symptoms similar to those of dothistroma needle blight (DNB) has been found affecting large areas planted to Pinus spp. The aim of this study was to identify the causal pathogen as well as to document the levels of disease incidence and severity. Isolates from each of three forestry zones, collected from different host species, were compared based on rDNA sequence of the ITS regions. These were conclusively identified as Dothistroma septosporum, one of two Dothistroma spp. known to cause DNB. Susceptibility was greatest on low elevation Pinus tecunumanii followed by Pinus kesiya and Pinus oocarpa. Pinus maximinoi and high elevation P. tecunumanii showed tolerance to D. septosporum. The disease incidence in the different zones varied significantly with the North zone being the most severely affected. This constitutes the first report of disease distribution and susceptibility of hosts, as well as the first consideration of the relative importance of D. septosporum in Colombia. 相似文献
94.
利用降水实况资料、单站地面资料、FY2E云顶亮温和NCEP、ECMWF格点资料,对2012年7月20日(7·20)、29日(7·29)腾格里沙漠发生的2次暴雨过程进行了诊断分析.结果表明:20:00局地热力环流在抬升、水汽动量辐合等方面为暴雨提供了有利条件,但它们必须得到天气系统的加强和优化,才能触发中尺度对流天气;沙漠的北边界为持续的水汽输入,南、东边界在暴雨前后由输入转为输出,西边界则由输出转输入,水汽源地在南海、孟加拉湾以及高纬地区;2次暴雨过程都在有利的大尺度环流背景和高低层天气系统相互作用下产生,垂直方向上形成抽吸结构;7·29过程前期为强不稳定层结,引发暴雨的中尺度系统是MCC,而7·20过程层结相对较稳定,观测点降水主要由中β尺度对流系统引起,这是7·29过程降雨大于7·20过程的原因. 相似文献
95.
《Communications in Soil Science and Plant Analysis》2012,43(16):2408-2427
The accuracy of suggested soil thresholds for diagnosing calcium (Ca), potassium (K), and phosphorus (P) deficiencies in sugar maple (Acer saccharum Marsh.) stands was tested and updated when possible. With respect to Ca, the combination of Ca saturation of the mineral B horizon (threshold: ≤28.4%), and the humus Ca/magnesium (Mg) ratio (≤5.322) and humus Ca saturation (≤59.7%) best partitioned the foliar Ca diagnosis with an overall accuracy of 80.5%. For K, the combination of either optimum thresholds of the K/Mg ratios in the humus (≤0.324) and upper B (≤0.436) soil horizon and the humus Ca/Mg ratio (≤4.382) had the best overall accuracy (76.3%). For P, the combination of base saturation (≤33.4%) and Mg saturation (≤9.6%) of the mineral B horizon and humus K/Mg ratio (≤0.187) yielded a conservative diagnosis with 92.0% specificity and an overall accuracy of 72.3%. 相似文献
96.
《Communications in Soil Science and Plant Analysis》2012,43(5):996-1010
Based on correlations calculated from the database of long-term fertilization experiments carried out in Hungary between 1960 and 2000, a new, cost-saving, and environmentally friendly fertilizer recommendation system was developed. The aim of the new system is to apply the lowest possible nitrogen (N)–phosphorus (P)–potassium (K) rates required to achieve good yields and maximum income per unit area. The World Phosphorus Institute (IMPHOS) agreed to finance a 3-year program to test various Hungarian fertilizer recommendation systems (the new RISSAC-RIA [Research for Soil Science and Agricultural Chemistry‐Research Institute for Agriculture] system, the Talajer?gazdálkodás integrated soil fertility management system, and the intensive MÉM NAK [Department of Plant Protection and Agricultural Chemistry of the Ministry of Food and Agriculture] system) when applied to three major crops grown on three characteristic Hungarian soils. The first five treatments in the experiment represented a classical deficiency experiment, aimed at checking the correctness of the NPK supply categories determined by the various systems. On all three soils and for all three crops the IMPHOS experiments confirmed the basic principles of the new cost-saving, environmentally friendly fertilizer recommendation system and the correctness of the methods used for calculating fertilizer rates. In this article, diagnostic plant analysis, soil analysis data, and NPK balances obtained in the different recommendations are discussed. In most cases the plant NPK contents of all the recommendations exceeded the lower limits of the good NPK supply category for wheat and barley shoot as well as for corn leaf. Crop NPK contents in Talajer?gazdálkodás and MÉM NAK treatments (with greater recommended NPK doses) were most cases better than in the RISSAC-RIA treatments; however, the better crop NPK status did not result in extra grain yield in the former treatments. Taking into account that similarly high yields were obtained using the RISSAC-RIA system and the Talajer?gazdálkodás integrated system with much smaller NPK doses than those recommended by the intensive MÉM NAK system, it was more advantageous from agronomic, environmental protection, and economic points of view. Differences in PK balances correlated well with the differences in the measured soil ammonium lactate (AL)–PK contents after the third year of the experiment. 相似文献
97.
为了更好地助力于飞速发展的福建省养殖业,依托日益普及的移动3G通讯技术,设计开发了基于安卓的动物疫病远程诊断系统。从动物疫病远程诊断系统的总体设计思路、系统实现的方式方法及最终所实行的功能等几方面进行阐述,说明了该系统具有简单实用,方便易推广的特点,它终将成为全省广大养殖户和农业专家工作的好助手。 相似文献
98.
99.
基于产量响应诊断冬小麦水分亏缺适宜土层及其水分阈值 总被引:4,自引:3,他引:1
明确作物产量对水分亏缺的响应是实施非充分灌溉的科学基础。该文在华北气候下,通过设置不同灌水次数造成处理间的土壤供水差异,探讨了大田冬小麦籽粒产量与不同生育时期、不同土层深度的土壤水分之间的关系,系统分析了影响小麦产量的水分阈值,提出了适宜的土壤水分诊断深度。结果表明:不论从土壤水分动态、还是从全生育期平均水分来看,亏水处理与充分供水对照在浅层土壤的水分差异最大,且随土层深度增加而减小。0~0.4、0~0.8、0~1.2 m的水分差异分别在19.7%~36.5%、9.3%~21.7%和2.9%~9.7%之间。此外,土壤水分变异程度随土层深度增加而减小。不同生育期、不同深度的水分与小麦产量关系多为开口向下的抛物线函数,但函数关系的显著程度随生育期及土层深度而变化,其中0~0.4 m的水分与产量关系最为密切。影响小麦产量的水分阈值随生育进程呈下降趋势。自拔节孕穗至乳熟期,0~0.4、0~0.6、0~1.0、0~1.2及0~1.6 m的水分阈值由田间持水率的83.1%~95%下降到72.3%~90.0%。依据处理间土壤水分动态差异、全生育期平均水分差异、不同土层的水分变异程度、土壤水分与小麦产量关系显著性程度4方面的分析,该文提出0~0.4 m为适宜的水分亏缺诊断深度,相应在拔节孕穗、抽穗、开花、灌浆初期、灌浆中期、灌浆后期、乳熟期的水分阈值分别为95.0%、98.4%、79.9%、73.7%、88.6%、79.6%和75.7%。该结果对小麦亏缺灌溉管理具有实际指导意义。 相似文献