乐至黑山羊的同期发情研究

乐至型川中黑山羊具有常年发情、产羔率高等优良繁殖特性,但是在极端气候条件下(炎热夏天和寒冷冬天)产的羔羊成活率低,因此,本研究拟建立同期发情率高、受胎率高和产羔率高的山羊同期发情方法以调整产羔季节.研究选取健康黑山羊63只,随机分为A、B、C三个组.在同一时间给每只羊放置CIDR阴道栓,处理13天后撤栓,同时注射PGF_(2α),然后注射不同剂量的PMSG:A组(n=20)不注射,B组(n=20)300IU,C组(n=23)500IU.母羊发情后用公羊自然交配;观测到母羊发情后,颈静脉采血制备血浆,用ELISA法测定血浆生殖激素(FSH、LH、E_2和P_4)浓度.结果发现,撤栓后72h内A、B、C三个组的发情率分别为80.0%、100.0%和82.6%,受胎率分别为68.8%、90.0%和78.9%,产羔率分别为190.9%、238.9%和206.7%.各组间生殖激素(FSH、LH、E_2和P_4)浓度差异不显著.综上所述,本试验优化出乐至黑山羊同期发情方法,即CIDR处理13天,撤栓后肌肉注射PGF_(2α)及300IU的PMSG.     

川中黑山羊(金堂类群)和藏山羊PRLR基因cDNA克隆及序列分析

根据GenBank中绵羊的PRLR基因序列设计引物,以川中黑山羊(金堂类群)和藏山羊垂体总RNA为模板,通过RT-PCR技术对川中黑山羊(金堂类群)和藏山羊PRLR基因cDNA克隆及进行序列分析,以期为进一步研究该基因与山羊的繁殖性能奠定理论基础.结果表明:川中黑山羊(金堂类群)和藏山羊PRLR基因编码区均长1746bp,均编码581个氨基酸.川中黑山羊(金堂类群)PRLR基因编码区与藏山羊、绵羊、牛、牦牛野猪和人的同源性分别为99.71%、99%、95%、95%、83%和80%.以核苷酸序列构建分子系统进化树,川中黑山羊(金堂类群)先与藏山羊聚为一类,再与绵羊聚为一类,后与牛和牦牛聚为一类,然后与野猪聚为一类,最后与人聚为一类.     

Particle formation and growth in dilute aluminum(III) solutions : Characterization of particle size distributions at pH 5.5

Particle formation and growth over the 1–40 μm size range in dilute aluminum solutions (approx. 2 × 10⁻⁴ M) have been studied using an electronic particle counter. Sulfate, fulvate and hydroxide ion accelerate the rate of particle formation and changes of the particle size distribution over time. Increasing ionic strength (inert electrolyte) produces similar but less dramatic effects. Combinations of sulfate and fulvic acid or sulfate and inert electrolyte further accelerate the rate of particle formation. Aluminum chloride solutions at moderate ionic strength are devoid of supramicron particles after several days. A conceptual pathway model is developed which suggests that two different solids are formed when aluminum is added to fulvic acid solutions: an aluminum-fulvate precipitate and Al(OH)₂(s). The first solid dominates in fulvic acid solutions at pH 5.5.     

Biochemical studies of some hydrolytic enzymes in malathion treated germinating seeds of Vigna sinensis (l): effect of growth hormone supplementation

Studies have been carried out on the different hydrolytic enzymes of the germinating seeds of V. sinensis (L) by exposing them to various concentrations of malathion (O, O dimethyl phosphorodithioate of diethyl mercaptosuccinate), an organophosphorus insecticide. At 50 ppm the insecticide induces the seedling growth and at 400 ppm caused a significant inhibition. On simultaneous application of either of the plant hormones, i.e., IAA, GA₃ and kinetin with different concentrations of malathion, it was found that there was a trend to overcome of malathion inhibition of seedling growth. It was also found that treatment of seeds with growth hormones, at 400 ppm malathion exposure, helps to restore the normal activities of certain hydrolytic enzymes, which showed otherwise, significant altered activities. Kinetic studies show that the stimulation of acid phosphatase activity due to malathion exposure was non‐competitive in nature.     

日本公众参与社区规划研究之二：社区培育的起源与发展（上）

日本的社区培育活动起源于社区居民对影响自己环境公害的抵抗运动。在其起源与发展的第一个阶段,主要有居民抵抗运动、住环境改善、历史街区保全运动和住宅开发社区培育运动等基本的活动形式。1970年代作为第二个阶段,是对各种形式社区培育活动的基础的实验阶段。除了上述5种形式之外,增加了环境的社区培育、福祉的社区培育、住民参加的社区培育、自发的地域活性化运动引发的社区培育等更多种类的实验。     

空调节能技术和措施的辨识(2)——地板送风系统设计中的困惑(上)

通过文献阅读、实验研究、工程调查,分析了现行的地板送风系统负荷计算和送风量确定过程中存在的主要问题。实验室实验和工程实践结果表明:在国内采用地板送风系统的一般办公室中,很难形成空气分层,分层与否影响空调送风量,而送风量又决定了空气是否分层;地板送风系统的负荷和送风量计算与顶送风常规空调系统并无本质区别,考虑到人体舒适感,地板送风系统的送风温度更高,送风量一般明显大于顶送风常规空调系统。空调负荷和送风量计算是地板送风系统设计中的关键,其正确与否,不但影响系统的经济性,而且还会影响系统的可行性,有必要进行深入的研究、分析和探讨。     

Cadmium toxicity to ringed seals (Phoca hispida): an epidemiological study of possible cadmium-induced nephropathy and osteodystrophy in ringed seals (Phoca hispida) from Qaanaaq in Northwest Greenland

The Greenland marine food chains contain high levels of cadmium, mercury and selenium. Concentrations of cadmium in the kidney of ringed seals (Phoca hispida) from the municipalities of Qaanaaq and Upernavik (Northwest Greenland) are among the highest recorded in the Arctic. The purpose of the study was to determine whether cadmium-induced damage in the kidneys and the skeletal system could be detected among 100 ringed seals from Northwest Greenland. The cadmium concentrations in the kidney cortex ranged from 0 to 248 microg/g wet weight (mean=44.5, N=100) in the 99 kidneys examined. Experience from cadmium-poisoned humans and laboratory mammals indicates that concentrations above 50-200 microg/g wet wt. may induce histopathological changes. Overall, 31 of the ringed seals had cadmium concentrations in the kidney cortex above 50 microg/g wet wt., 11 had concentrations above 100 and one had a concentration above 200 microg/g wet wt. Obvious histopathological changes (categorised mainly as glomerulonephritis) were found in 10 of the seals; however, none of these changes could be attributed to cadmium-induced renal damage (mainly tubulopathy) as described for other species. Damage to the proximal kidney tubules is known to induce demineralisation of the skeletal system (Fanconi's syndrome). Therefore, the three lowest lumbar vertebrae were scanned in 91 seals to measure the content of calcium. The 10 cases of nephropathy could neither be linked to the degree of mineralisation of the skeleton nor to the cadmium concentrations. Furthermore, the degree of mineralisation of the skeleton was not correlated with the cadmium concentration, age or sex. It can therefore be concluded that despite high levels of cadmium, none of the ringed seals showed any signs of cadmium-induced nephropathy or osteodystrophy. This might be explained by the composition of the ringed seals diet, which contains high levels of vitamin D, calcium, phosphorus, zinc, selenium and protein. These elements are all likely to counteract cadmium-induced damage. It is speculated that ringed seal are not particularly vulnerable to osteodystrophy, due to their continuous growth (bone mineralisation) throughout life and the oestrogen hormonal activity of females throughout life.     

Kuy-e Narmak (1952–1958): the growth and change of an urban community in Tehran

ABSTRACT

This article examines the growth and change through time of Kuy-e Narmak, a housing neighbourhood developed in the 1950s under the auspices of Mosaddeq’s Modernization Program. The project was designed by a group of young-leading European-educated Iranian architects that collaborated with the government to develop affordable housing solutions in Iran. To design this project, these architects advanced solutions that explored a cross-pollination between the principles of the functional city, and references from vernacular architecture. Over the last 6 decades, the number of households living in Narmak increased dramatically, from the initial goal of accommodating 7500 families, to the 90,000 families that currently live there. This article discusses the extent to which the initial design decisions were instrumental to cope with this extraordinary increase in the district’s density. We have used typological and morphological analysis, combined with site surveys and interviews to investigate the district’s growth and change through time. This article argues that the designer’s critical combination of modernist planning concepts with elements borrowed from Iran’s vernacular tradition resulted in a socially inclusive urban community. The plan’s rigid urban form has become instrumental in defining a neutral background to accommodate the ever-changing social and spatial practices of its inhabitants.     

Economic growth and development in Macau (1999–2016): The role of the booming gaming industry

In 2018, Macau will celebrate the 20th anniversary of its return to China. The past few years have witnessed brilliant economic achievements as well as a structural shift toward a gaming-industry dominated economy. Following so many years of rapid growth, it is essential to take stock of both the benefits and costs of gaming industry development. Accordingly, this paper analyzes the evolution of Macau's gaming industry between 1999 and 2016, and evaluates the industry's effects on local economic growth and urban development. As the paper shows, Macau has exhibited many of the symptoms typically associated with booming sectors in small economies, and has witnessed the similar effects widely experienced by western casino cities. However, Macau is also faced with some unique challenges, regarding its geographic location, size constraints, and political factors. These findings illustrate the difficulties that have accompanied Macau's economic achievements, but also call attention to opportunities in the next phase of Macau's development.     

Migration of fallout radiocaesium in a grassland soil from 1986 to 2001. Part I: activity-depth profiles of (134)Cs and (137)Cs

The temporal changes of the vertical distribution of (134)Cs (deposited by the Chernobyl fallout in 1986) and (137)Cs (deposited by the Chernobyl and the global fallout) in the soil were investigated at an undisturbed Bavarian grassland site in Germany. At ten sampling dates between 1986 and 2001, the activity density of (134)Cs and (137)Cs was determined in various soil layers down to 80 cm depth. In 2001, the small-scale spatial variability of the radiocaesium activity was determined by sampling five plots within 10 m(2) (coefficient of variation about 20% for the upper soil layers). Between 1987 and 1990, substantial changes of the activity-depth profiles were observed. The percentage depth distributions of (134)Cs and (137)Cs were rather similar. The 50%-depth of the accumulated activity increased from 2.4 cm in 1988 to 5.3 cm in 2001 for (134)Cs and from 2.7 to 5.8 cm for (137)Cs. This indicates that at the study site the migration data of Chernobyl-derived (137)Cs can be estimated by those of total (137)Cs. In the second part of this study, the activity-depth profiles will be evaluated by the convection-dispersion model [Schimmack, W, Feria Márquez, F. Migration of fallout radiocaesium in a grassland soil from 1986 to 2001. Part II: Evaluation of the activity-depth profiles by transport models. Sci Total Environ 2006-this issue].     

Effects of 17alpha-ethynylestradiol in a partial life-cycle test with zebrafish (Danio rerio): effects on growth,gonads and female reproductive success

In this study, the impact of an exposure of zebrafish embryos (Danio rerio) until 3 months post fertilization to 17alpha-ethynylestradiol (EE2: 0; 0,1; 1; 10; 25 ng/l) was evaluated for growth and development, gonad development and body vitellogenin (VTG) content. After a recovery period of 5 months, the female reproductive success was evaluated. The results demonstrated a significant reduction in total body length, body weight, whole body Ca and P content and an increase in morphological abnormalities for fish exposed to 25 ng/l EE2 as a function of exposure time. An increase in total body VTG content was observed for fish exposed for a period of 3 months down to levels of 1 ng/l EE2. At the age of 3 months, a dose-dependent increase of the number of fish with no macroscopic recognizable gonads was observed (up to 100% at 25 ng/l EE2). After a recovery period on clean tap water for 5 months, all fish had developed either ovaries or testis with a gonadosomatic index not different from control fish and the sex ratio was similar in EE2 treatment groups and controls. Nevertheless, a reduced number of spawning females and a reduced egg production were found for the female fish exposed to 10 or 25 ng/l EE2 for 3 months and which were allowed to recover for 5 months. Although the underlying mechanism could not be elucidated, these findings did indicate that the reproduction potential of fish populations might be disturbed by a long-term exposure to EE2 (> or =10 ng/l) from fertilization until sexual maturity.