电力电缆故障定位的探讨

随着中国的快速发展,中国的城市建设和不断完善,在同一时间,社会和经济快速发展,现在有对电力的需求不断增长,对电力的依赖程度也越来越高,所以,在对电力设施的建设中,必须也不断完善。而检测确定电力电缆中出现的问题也需要花费大量的时间精力。因此,本文就如何快速准确的找到电力电缆故障点进行了分析,并相应提出建议。     

基于北斗的高精度定位车载导航系统的设计

随着导航系统的发展,车载导航系统的装配量越来越大,用户和市场对导航系统的定位精度要求越来越高。本文设计了基于北斗高精度定位车载导航系统,装配了具有强大处理能力的处理器和适合航位推算的传感器模块。不仅采用高精度定位模块提高了定位精确度,而且从软件方面也可以提高定位精确度,例如采用提高定位精确度的成熟算法,例如卡尔曼滤波、航位推算及地图匹配等。可以达到车道级定位精确度。     

家畜数量性状基因定位研究进展

在数量遗传学理论形成之初，大量的研究证实，数量性状的遗传基础，仍然是遵循孟德尔遗传规律的基因。由于影响数量性状的基因数目较多，在当时的条件下无法辨认其各自的效应，于是便有了著名的微效多基因学说（ＮｉｌｓｓｏｎＥｈｌｅ１９０９）。尽管这一学说对数量性状的遗传基础作了相当简单化的假定，但在当时的理论和技术条件下仍不失为一个很好的基础，数量遗传学的主要技术体系就是在这一基础上建立的。但是，由于这一学说不了解数量性状的遗传背景，不知道控制数量性状的基因在染色体上的位置及其传递行为，因而就无法对其效应值…     

试论移动通信定位技术

导航与位置服务关系国家安全、经济发展和社会民生，是战略性产业，其技术基础是移动定位技术。为了对移动定位技术进行全面清晰的阐述。针对移动定位技术发展状况，分析目前主流定位技术的优劣，并对取得的突破作简单的总结归纳。     

半同胞群体QTL区间定位的通用SAS程序

在家畜中普遍存在的是分离群体．在数量性状基因定位方面．由于分离群体在各个家系内标记之间及标记与QTL之间的连锁状态不同,同一位点可能存在着多个等位基因,且只有部分个体提供信息,因而在分离群体中进行QTL定位时,其资源群体要以家系为单位,估计的参数也是以QTL方差组分为主。半同胞设计是家畜QTL分析的常用方法．设计中以父系半同胞为资源群体．利用父系及其半同胞后代的标记信息和表型信息进行QTL分析。     

品牌定位的三角亭模型

自从1972年美国营销专家艾尔·里斯和杰克·特劳特在《广告时代》发表了“定位时代”系列文章以来，定位观念在理论界和企业界得到广泛共鸣。2001年，当美国营销学会评选“有史以来对美国营销影响最大的观念”时，定位理论击败众多强劲对手，获得这一殊荣。     

基于RSSI测距的煤矿井下人员定位算法的改进

目前,基于RSSI测距的煤矿井下人员定位算法是国内外井下人员定位常用的一种算法。可是RSSI测距由于受到井下障碍物的隔离以及节点间的相互干扰等因素,常常导致测距产生误差较大,此时如果再用传统的简单点,构成四个定位三角小区,根据定位三角小区各个三角顶点归属的定位三角小区个数的不同,进行加权的求三角形质心的方法定位井下人员的位置时,可能偏差会比较大。针对这一问题,本文提出选取四个定位节定位算法,近而提高定位精度。     

畜禽基因定位的现状和展望

本文对畜禽基因定位的内容、方法和现状进行了综述。提出了基因定位中存在的主要问题是定位精度不高，方法有待进一步完善。我国开展此项工作应将重点放大中国畜禽特有性状和重要经济性状上。     

常用的RFID室内定位算法研究

随着无线通信、物联网和计算机技术的蓬勃发展,室内无线定位技术正逐渐受到越来越多人的关注。由于室内环境的复杂性和不可控性,对高精度的室内定位算法的研究就显得尤为重要。文章对几种常用的无线射频识别室内定位算法进行了研究,为今后算法的改进奠定了基础。     

传递不平衡检测及其在QTL精细定位中的应用

在早期的QTL定位研究中,研究者所关注的主要是QTL检出效率的高低.随着QTL定位研究的不断深入,研究者们发现:即使是在QTL检出效率很高的情况下,其定位的精确性仍然可能很低.就目前的定位精度来看,虽然基本可以满足实施标记辅助选择的要求,但还远远不能满足分子克隆技术所能达到的操作程度.因此有必要寻找新的定位策略以达到QTL精细定位的目的.本文简要综述了QTL精细定位新策略一传递不平衡检测(TDT)的概念及发展、原理与方法及其在QTL精细定位中的应用.     

奶牛发情周期中毛 唾液和乳汁孕酮水平的变化

本实验采用放射免疫分析法(RIA)测定了11头奶牛一个发情周期里毛、唾液、乳汁中孕酮(P_4)含量。经产牛(n=8)的毛和唾液中P_4水平变化与乳汁中P_4水平变化一致。青年牛(n=3)的毛和睡液中的P_4水平变化一致,并分别与经产牛毛和唾液中P_4水平变化一致。7头配种后的经产牛和5头配种后的青年牛分别取20和23天的样品进行妊娠诊断,与配种后60天的直检结果相对照,依据经产牛毛、乳P_4水平进行妊娠诊断的阳性准确率分别是85.7％(6/7)和100％(7/7),依据青年牛毛P_4水平进行妊娠诊断的阳性准确率为100％(5/5)。     

玉米赤霉烯酮对后备母猪子宫和卵巢抗氧化和炎症指标及相关基因表达的影响

试验旨在研究玉米赤霉烯酮（zearalenone,ZEA）对后备母猪子宫和卵巢抗氧化和炎症指标及相关基因表达的影响。选择胎次和体重（（23.20±0.68）kg）相近的长×大二元后备母猪48头,随机分为4组,每组设12个重复,每个重复1头母猪。对照组（CON组）饲喂基础饲粮,试验组（T1、T2、T3组）饲喂在基础饲粮中分别添加200、800、1600 μg·kg^-1ZEA的试验饲粮。预试期7 d,正试期40 d。结果如下：1）与CON组相比,T3组血清T-AOC和SOD活性显著降低（P<0.05）,MDA水平显著升高（P<0.05）。2）与CON组相比,子宫组织中,T2和T3组T-AOC活性显著降低（P<0.05）,T3组SOD活性极显著降低（P<0.01）,卵巢组织中,T3组T-AOC活性、T2组GSH-Px和SOD活性显著降低（P<0.05）,T3组MDA水平显著升高（P<0.05）。3）与CON组相比,T2组血清TNF-α和IL-4水平显著升高（P<0.05）,T1~T3组血清IL-10水平显著降低（P<0.05）。4）与CON组相比,子宫组织中,T2组IL-1β水平显著升高（P<0.05）,T1和T3组IL-10水平显著降低（P<0.05）。卵巢组织中,T2组TNF-α水平显著升高（P<0.05）,T1~T3组IL-4水平显著升高（P<0.05）。5）子宫组织中,T3组Cu/Zn-SOD mRNA的相对表达显著低于CON组（P<0.05）,T2组IL-1β mRNA的相对表达显著高于CON组（P<0.05）。6）卵巢组织中,T3组GSH-Px mRNA的相对表达显著低于CON组（P<0.05）,T2组IL-1β mRNA的相对表达显著高于CON组（P<0.05）。综上所述,ZEA能通过抑制SOD和GSH-Px的表达与合成,降低后备母猪子宫和卵巢的抗氧化性能,并引起氧化应激。ZEA能通过促进TNF-α和IL-1β表达与合成引起子宫和卵巢的炎症反应,抑制IL-10的表达与合成从而抑制两组织的抗炎反应。     

泌乳期山羊腺垂体中ERα和ERβ的分布特点

为了获得ERα和ERβ在泌乳期参与腺垂体激素分泌的调节机理的形态学依据,试验采集泌乳初期、泌乳中期和泌乳后期山羊的腺垂体,用免疫组化SP法检测了ERα和ERβ在腺垂体的分布.结果表明,山羊腺垂体中ER两种亚型分布在腺垂体远侧部的嗜色细胞中；ERα阳性细胞数量随泌乳时间逐渐减少,泌乳初期和泌乳后期多呈胞质阳性,高峰期呈胞...     

Immunohistochemical study on the expressions of neuropeptides in the superficial and deep gland of the third eyelid of pigs

The superficial gland of the third eyelid (SGTE) and deep gland of the third eyelid (DGTE) are classified as accessory lacrimal glands. The aim of the present study was to immunohistochemically investigate the expression of vasoactive intestinal peptide (VIP), dopamine beta-hydroxylase (DβH), substance P (SP), galanin, neuropeptide Y (NPY), pituitary adenylate cyclase-activating peptide (PACAP), somatostatin and calcitonin gene-related peptide (CGRP) in the porcine SGTE and DGTE. We demonstrated the distribution patterns of VIP, DβH, SP, NPY and galanin in the nerve fibres in the SGTE and DGTE. None of somatostatin-, PACAP- and CGRP-immunoreactive (IR) nerve fibres were found in the SGTE and DGTE. The majority of VIP- and DβH-IR nerves fibres were found near to glandular acini, tubules, secretory ducts and blood vessels in the SGTE and DGTE. VIP-IR nerve fibres were found in external connective tissue in SGTE and DGTE and only in interlobular connective tissue in the SGTE. DβH-IR nerve fibres were found in interlobular and external connective tissue in the DGTE but not in the SGTE. Single galanin-, SP- and NPY-IR nerve fibres were observed in close proximity to acini and tubules in the SGTE and DGTE. Single galanin-, SP-, NPY-IR nerve fibres were found in close proximity to the secretory ducts in the DGTE, however only SP-IR nerve fibres were found near to the secretory ducts in SGTE. In conclusion, our research aims to highlight some aspects of SGTE and DGTE innervation in pigs and may also be a source of basic knowledge for further studies.     

Immunohistochemical study of galectin-3 in mature and immature bull testis and epididymis

Galectin-3, a member of the β-galactoside-binding protein family, has been implicated in mammalian sperm maturation. We examined galectin-3 expression in the testis and epididymis of sexually mature and immature bulls. Western blot analysis showed varying levels of galectin-3 in the bull testis and epididymis, and galectin-3 immunoreactivity was higher in the mature testis and epididymis than in immature organs. Galectin-3 was primarily localized in interstitial cells of the immature bull testis and in the peritubular myoid and interstitial cells of the mature testis. In the immature epididymis head, galectin-3 was primarily in the principal and basal cells of the epithelium. In the mature epididymis head, moderate levels of galectin-3 were detected in the sperm, while low levels were found in the stereocilia, epithelium and connective tissue. In the immature epididymis body, moderate protein levels were detected in the principal cells, while lower levels were found in the basal cells. The mature epididymis body showed moderate levels of galectin-3 immunostaining in the stereocilia and epithelium, but low levels in the connective tissue. In the immature epididymis tail, only low levels of galectin-3 staining were found in the epithelium, whereas the mature epididymis tail showed high levels of galectin-3 in the principal cells, moderate levels in the basal cells and low levels in connective tissue. These findings suggest that galectin-3 expression plays a role in the maturation and activation of sperm in bulls.     

Measurement of Faecal Cortisol Metabolites in Cats and Dogs: A Non-invasive Method for Evaluating Adrenocortical Function

The aim of this comparative study was to gain more information about the metabolism and excretion of glucocorticoids in cats and dogs in order to establish non-invasive methods for evaluating stressful conditions. Therefore, in a first experiment, [¹⁴C]cortisol was administered intravenously to 8 animals (two of each sex and species). Over a period of 6 days, faeces and urine were collected immediately after spontaneous defecation and urination. Marked species differences were found, as cats mainly excreted cortisol in the faeces (82%±4% of the total recovered radioactivity), whereas in dogs only a small portion was found there (23%±4%). The highest urinary radioactivity was observed after 9±3 h in cats and 3±1 h in dogs. Peak concentrations in the faeces occurred after 22±6 h in cats and after 24±4 h in dogs. Most of the radioactivity was not extractable with diethyl ether, indicating that the metabolites excreted in urine and faeces were mainly of the conjugated or polar unconjugated types. This was confirmed by RP-HPLC, which also revealed marked differences between cats and dogs concerning the metabolites formed. In addition, the immunoreactivity of the metabolites was tested in cortisol, corticosterone and 11-oxoaetiocholanolone EIAs. The latter, measuring 11,17-dioxoandrostanes (11,17-DOA) detected the highest quantities of immunoreactive metabolites in cats, but not in dogs. In a second experiment, the adrenal cortex of both species was stimulated by ACTH and, three weeks later, suppressed by dexamethasone. In this study, only faeces were collected over a period of 7 days. In both species, inter-animal variability in the basal and maximal/minimal faecal cortisol metabolite concentrations and the time course was observed. The 11-oxoaetiocholanolone EIA in cats and the cortisol EIA in dogs proved best suited for monitoring changes in adrenocortical activity. ACTH injections resulted in an increase above baseline values of 355% (median) in 11,17-DOA concentrations in cats and of 702% in the concentrations of cortisol equivalents in dogs by about 25 h and 22 h (median) after injection, respectively. Minimal concentrations after dexamethasone administration were about 17% in cats and 31% in dogs (in relation to baseline values) and were reached in 66 h and 72 h, respectively. It was concluded that measuring cortisol metabolites in faeces should be a useful non-invasive tool for monitoring stress in carnivores.     

Clinicomorphological Studies in Chicks Fed Ochratoxin A While Simultaneously Developing Coccidiosis

The progression of coccidiosis and the resultant mortality were followed in chicks fed a OTA-contaminated diet. More complex and rapid progress of coccidiosis occurred in OTA-treated chicks than in chicks fed a OTA-free diet. The concentration of total protein in the serum was significantly decreased in the chicks in the OTA-treated group, whereas this was significantly increased in chicks infected with Eimeria tenella, irrespective of additional treatment with OTA. The serum glucose concentration was significantly increased in all the chicks exposed to OTA and/or suffering from coccidiosis, as was serum retention of uric acid in all groups, most notably in those consuming OTA. OTA induced degenerative changes in, and an increase in the weight of the kidneys, liver, heart and ventriculum; there was depletion of lymphoid tissue and a decrease in the lymphoid organs' weight and body weight. Coccidiosis induced only a slight growth depression and a slight increase in the relative weight of the kidneys and liver. The intensity of the clinical signs, the impairment of kidney function, macroscopic and histopathological changes, deviations in the weight of some organs and general depression in growth were greater when chicks infected with E. tenella were also given OTA.     

Effect of Immunosuppression on the Clinicopathological Changes in Experimental Zygomycosis in Rabbits

A study was undertaken to investigate the effect of immunosuppression by cyclophosphamide or methylprednisolone on the clinicopathological alterations in respiratory absidiosis in rabbits. Infected rabbits showed respiratory distress that was more severe in immunosuppressed groups. Leukocytosis due to neutrophilia was observed in the non-immunosuppressed group in the initial stages, whereas leukopenia was observed in both the immunosuppressed groups initially, owing to polymorphopenia in the cyclophosphamide-treated group and to lymphopenia in the methylprednisolone-treated group, followed by leukocytosis in both groups. Total serum proteins increased significantly in the non-immunosuppressed group but were significantly decreased in the immunosuppressed groups. Serum creatinine increased significantly in all the infected groups from 20 days post inoculation (DPI) onwards. Blood urea nitrogen increased significantly in the initial stages only in the methylprednisolone-treated group. AST and ALT also showed significant increases in the infected animals. Total serum immunoglobulins and circulating immune complexes increased gradually in all three infected groups, except for an initial significant drop in the immunosuppressed rabbits. Re-isolation of fungus was only achieved from the lungs of infected rabbits up to 15 DPI in the non-immunosuppressed group and 30 DPI in the immunosuppressed groups. Pathological lesions in all the infected groups were found mainly in the lungs and consisted of pyogranulomas. The lesions were most severe in the cyclophosphamide-treated group and least severe in the non-immunosuppressed group.     

奶牛养殖小区育成牛粪中污染因子的四季动态监测研究

本文研究了奶牛养殖小区育成牛粪中污染因子的季节变化规律,结果表明,育成牛鲜粪中含水率春季最低,冬季最高;风干粪样中,除夏季全氮和全磷顺序颠倒外,五项检测指标及其年均值的季节变化规律均保持一致,即有机质〉全氮〉全磷〉锌〉铜;育成牛全氮含量夏季最低、冬季最高,全磷含量秋季最低、夏季最高,有机质含量夏季最低、秋季最高,铜含量夏季最低、春季最高,锌含量春季最低、夏季最高。     

短花针茅荒漠草地放牧系统微量元素季节变化及盈缺分析

为更有效地防治内蒙古自治区四子王旗地区家畜微量元素代谢病,合理使用微量元素添加剂,采用实地采样和实验室分析相结合的方法,对该地区短花针茅（Stipa breviflora）荒漠草地土壤-牧草-家畜生态系统中微量元素的水平进行检测。结果显示,土壤中铜和硒处于缺乏状态。牧草中铁和锰元素处于过量状态,硒为缺乏状态。与健康绵羊的各项指标相比较,血浆中铁和锰分别于夏秋季节和全年高于正常水平,硒和铜元素分别于秋季和冬季低于正常水平;肝脏中铁和锰全年高于正常水平,铜冬季低于临界值,硒元素秋冬季节低于正常水平;被毛中铁全年高于正常水平,而铜和硒全年低于正常水平。结合放牧绵羊对各种矿物质的进食量和消化率进行综合分析表明,该地区为高铁、高锰、低硒的生态环境,同时铜和锌处于季节性缺乏状态。