Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season

The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n  = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p  < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p  < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p  < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p  < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p  < .05) and monocytes (2.93 ± 0.13; p  < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer.     

大型灯泡贯流式泵站振动研究概述

机组和泵房的振动是泵站运行中最为常见的问题，直接影响泵站的安全可靠运行。对大型灯泡贯流式泵站振动研究现状和抗振安全评价计算分析方法作了详细的介绍，对研究机组振动诱发泵房振动的共振校核法、拟静力法、谐响应求解法和瞬态动力时程法等进行了阐述，并对这几种方法进行了分析比较，就其存在的问题作了总结概述。     

几种甘蓝型油菜幼苗抗旱性特征的比较研究

以EV1、EV2、EV3、EV4、EV5、EV66个抗旱性不同的油菜品种为试验材料,通过不同浓度PEG-6000渗透溶液模拟干旱胁迫处理,研究油菜幼苗的抗旱指数、根长、苗高和根冠比等性状变化,探索在大田环境条件下的苗期生长特征。结果表明,水分胁迫下EV2的抗旱指数最大,EV6的抗旱指数最小;不同浓度PEG胁迫下,各品种差异显著, EV1、EV2、和EV3的根长、苗高和根冠比较大,而EV5和EV6的表现较差。在大田油菜五叶期时,EV2的冠层覆盖面积最大,与其它品种之间存在极显著性差异;总生物量以EV2、EV3和EV1较大,根系干重以EV2较大,而且三者之间存在显著相关性;与抗旱指数进行通径分析,冠层覆盖面积对抗旱性的直接通径系数最大,达到0.5975。冠层覆盖面积的大小反映了早期活力的强弱,早期活力强,相应的品种抗旱指数高,抗旱性强。     

Agglomeration and Competition among Chinese Cities: An Investigation of Taiwanese High‐Tech Foreign Direct Investment

The purpose of this study was to investigate how Taiwanese high‐tech firms' foreign direct investment (FDI) leads to agglomeration and competition among cities in China. By using social network analysis to analyze 1,111 subsidiaries affiliated with 270 multinational corporations (MNCs) during the years between 1988 and 2006 in 30 major Chinese cities, this study finds that: 1) agglomeration in Chinese cities falls into three primary categories: the hub cluster, the communication‐extended cluster, and the computer‐extended cluster. Among the aforementioned clusters, the hub cluster is the most critical in terms of firm location, and therefore is often a high‐priority investment site for Taiwanese high‐tech firms. 2) Chinese cities fall into four primary groups, or “blocks”: the core block, the coast block, the inland block, and the periphery block; these groups were determined by applying a structural equivalence analysis of which members of each type are in competition with one another. By linking the findings of the urban network characteristics to Chinese regional economic policies, this study provides guidance to aid executives in determining the optimal location for future FDI. Implications and suggestions for host country governments in terms of firms' investment strategies are also discussed.     

黄土耕作坡面溅蚀过程中微地形响应特征

[目的]探究60mm/h雨强下不同耕作坡面在溅蚀阶段的微地形变化特征,为黄土坡地水土保持耕作方式布设提供科学依据。[方法]在室内人工模拟降雨试验的基础上,采用激光扫描量测方法分别获取溅蚀前后4种不同耕作方式(人工锄耕、人工掏挖、等高耕作、耙磨整平)黄土坡面微地形相对高程,并对能反映微地形变化的高精度M-ΔDEM进行了分析。[结果]不同耕作措施下坡面微地形均具有较弱的空间变异,其空间分异主要受耕作措施的影响;降雨对微地形具有一定的夷平效应,且不同耕作坡面在1~1.3m尺度范围内均表现出侵蚀平衡现象;不同耕作微地形对溅蚀均具有阻滞作用,其中人工掏挖和等高耕作具有较强的水土保持作用。[结论]微地形水系分维能较好地反映复杂的微地形特征,而坡面耕作方式是溅蚀过程中微地形时空变异分布状况的控制性因子。     

L-Bupivacaine 0.5% vs. racemic 0.5% bupivacaine for caudal epidural analgesia in horses

Bupivacaine is available as a racemic mixture of its enantiomers, d -bupivacaine and l -bupivacaine (LB). The aim of this randomized, double-blind study was to investigate the clinical efficacy and safety of S(−)-bupivacaine compared with standard racemic bupivacaine (RB) in horses under caudal epidural analgesia. Two treatments were administered to each horse, with a 2-week interval between subsequent treatments. Treatment 1 consisted of 0.5% LB at a dose of 0.06 mg/kg of body weight, and treatment 2 consisted of 0.5% RB at a dose of 0.06 mg/kg of body weight. Epidural injections were given in all animals between the first and second coccygeal vertebra. Heart rate (HR), arterial pressures, respiratory rate (RR), rectal temperature (RT), analgesia, and motor blocking were determined before drug administration (basal) and 5, 10, 15 and 30 min after drug administration, and at 30 min intervals thereafter. There were no significant differences between the two treatments in the quality of sensory and motor block. The duration of analgesia was 320 ± 30 min (mean ± SD) for RB and 360 ± 42 min for LB. HRs and RRs, arterial pressures and RT did not change ( P  < 0.05) significantly from basal values after epidural administration of LB or RB. This study supports that 0.5% LB is an effective alternative to RB in caudal epidural analgesia in conscious, standing horses. The use of LB vs. RB warrants further investigation, particularly for long-lasting surgery in the perineal region.     

Tracking the evolution of a hydrothermal event plume with a RAFOS neutrally buoyant drifter

The migration and evolution of a deep ocean hydrothermal event plume were tracked with a neutrally buoyant RAFOS float. The float remained entrained in the plume for 60 days, and the plume vorticity was calculated directly from the anticyclonic motion of the float. Concentrations of suspended particles, particulate iron, and dissolved manganese in the plume did not decay significantly during the 60 days, which indicates that event plumes would be easily detectable a year after formation.     

Paleolithic population growth pulses evidenced by small animal exploitation

Variations in small game hunting along the northern and eastern rims of the Mediterranean Sea and results from predator-prey simulation modeling indicate that human population densities increased abruptly during the late Middle Paleolithic and again during the Upper and Epi-Paleolithic periods. The demographic pulses are evidenced by increasing reliance on agile, fast-reproducing partridges, hares, and rabbits at the expense of slow-reproducing but easily caught tortoises and marine shellfish and, concurrently, climate-independent size diminution in tortoises and shellfish. The results indicate that human populations of the early Middle Paleolithic were exceptionally small and highly dispersed.     

工厂化水产养殖水质监测系统

工厂化水产养殖的密度高、风险大,养殖对象对pH、溶解氧、温度、氨氮、亚硝酸盐等水质参数的变化敏感,受影响严重,监测水质参数极为重要。本文针对工厂化水产养殖水质监测特点和需求,研发了工厂化水产养殖水质监测系统。分析研究pH、溶解氧、温度、亚硝酸盐等水质参数的阈值,设计水质监测数据无线采集节点和基于Zigbee的无线监测网络,建立水质监测系统软件平台。结果表明,该系统能够实现工厂化水产养殖水质实时监测,保证生产安全,提高水产养殖生产效率。