Sperm bundle and reproductive organs of carabid beetles tribe Pterostichini (Coleoptera: Carabidae)

The morphological characteristics of sperm and reproductive organs may offer clues as to how reproductive systems have evolved. In this paper, the morphologies of the sperm and male reproductive organs of carabid beetles in the tribe Pterostichini (Coleoptera: Carabidae) are described, and the morphological associations among characters are examined. All species form sperm bundles in which the head of the sperm was embedded in a rod-shaped structure, i.e., spermatodesm. The spermatodesm shape (left-handed spiral, right-handed spiral, or without conspicuous spiral structure) and the condition of the sperm on the spermatodesm surface (with the tail free-moving or forming a thin, sheetlike structure) vary among species. In all species, the spiral directions of the convoluted seminal vesicles and vasa deferentia are the same on both sides of the body; that is, they show an asymmetric structure. The species in which the sperm bundle and the seminal vesicles both have a spiral structure could be classified into two types, with significant differences in sperm-bundle length between the two types. The species with a sperm-bundle spiral and seminal-vesicle spiral of almost the same diameter have longer sperm bundles than the species with a sperm-bundle spiral and seminal-vesicle tube of almost the same diameter. In the former type, the spiral directions of the sperm bundles and seminal vesicles are inevitably the same, whereas they differ in some species with the later type. Therefore, increased sperm bundle length appears to have been facilitated by the concordance of the sperm bundle’s coiling direction with the coiling direction of the seminal vesicle.     

Soil and preen waxes influence the expression of carotenoid-based plumage coloration

The signaling function of carotenoid-based plumage is mainly determined by the concentration of pigments in feathers. For this reason, most studies of the proximate control of coloration focus on processes during and preceding moult. In great tits Parus major, past research demonstrates that carotenoid-based plumage coloration honestly indicates male quality and, thus, may be a sexually selected signal. In this study, we investigate how dirt and preen oil influence the coloration of carotenoid-based feathers in the great tit. We collected six feathers from each individual bird; three feathers served as controls while the remaining three feathers were washed with a chloroform/methanol mixture to remove soil and preen waxes. We assessed plumage coloration using digital photography. This cleaning procedure slightly enhanced ornamentation; the experimentally cleaned feathers expressed hues shifted towards shorter wavelengths and expressed brighter overall coloration than control feathers. This is the first experimental study conducted on wild birds demonstrating that, in addition to pigment concentration, the presence of preen waxes and soils on feathers may contribute to variation in coloration.     

Daytime light intensity affects seasonal timing via changes in the nocturnal melatonin levels

Daytime light intensity can affect the photoperiodic regulation of the reproductive cycle in birds. The actual way by which light intensity information is transduced is, however, unknown. We postulate that transduction of the light intensity information is mediated by changes in the pattern of melatonin secretion. This study, therefore, investigated the effects of high and low daytime light intensities on the daily melatonin rhythm of Afro-tropical stonechats (Saxicola torquata axillaris) in which seasonal changes in daytime light intensity act as a zeitgeber of the circannual rhythms controlling annual reproduction and molt. Stonechats were subjected to light conditions simulated as closely as possible to native conditions near the equator. Photoperiod was held constant at 12.25 h of light and 11.75 h of darkness per day. At intervals of 2.5 to 3.5 weeks, daytime light intensity was changed from bright (12,000 lux at one and 2,000 lux at the other perch) to dim (1,600 lux at one and 250 lux at the other perch) and back to the original bright light. Daily plasma melatonin profiles showed that they were linked with changes in daytime light intensity: Nighttime peak and total nocturnal levels were altered when transitions between light conditions were made, and these changes were significant when light intensity was changed from dim to bright. We suggest that daytime light intensity could affect seasonal timing via changes in melatonin profiles. Professor Dr. E. Gwinner died on 07 September 2004.     

大型社会活动的事故预防与控制

大型社会活动的安全形势非常严峻,本文通过对大型社会活动安全管理中存在的问题和事故影响因素的分析,从事故预防和控制的角度提出几点措施.     

内部装修的消防安全隐患及对策

随着改革开放和市场经济的不断发展,人们生活质量的不断提高,对于建筑内部装修和布置要求也越来越高档、豪华、舒适,尤其是一些歌舞厅、KTV包厢、桑拿浴室、网吧等公共娱乐场所以及宾馆、饭店、大型商场等公共聚集场所和不在少数的居民家庭,为了减轻结构自重,方便建筑内空间的合理划分和追求室内装饰时尚、品味,忽视消防安全,在建筑中大量使用易燃、可燃高分子材料,并大量使用合成及塑料制作的家具.……     

Study of vehicle speeds on a major highway in Ghana: implication for monitoring and control

OBJECTIVE: Vehicular speeds have been identified to be at the core of road accident severity and frequency globally. Whereas speed control is a fundamental priority and the cornerstone of road safety in the developed world, the subject is at rudimentary stages in most developing countries thus making research into vehicle speeds in developing nations imperative. The main aim of the study was to establish two major speed parameters, namely the mean speed and dispersion, and their implications for more extensive and long-term speed monitoring in Ghana. METHODS: Research workers stationed themselves in a parked car and used a radar gun to unobtrusively measure the travelling speeds of 4,163 vehicles over two 24-hour periods at two separate sites on one of the main inter-urban roads (Accra-Kumasi). Both sites were settled areas with posted speed limits of 50 km/hr. RESULTS: Over 95% of vehicles travelled above the posted speed limit of 50 km/hr. Vehicles on an average travelled at 87 km/hr, (95% CI=87, 88). Variation in speeds was wide, with a standard deviation of 18 km/hr for all classes of vehicles, and with a range of 40 to 187 km/hr. The highest vehicular speed was associated with the private car (97.6+/-18.3 km/hr) followed by large buses (93.6+/-13.3 km/hr) and the least was with heavy trucks (73.8+/-12.9 km/hr). CONCLUSION: The excessive vehicular speeds coupled with the wide speed variations explain in part the high incidence of traffic crashes and fatalities on the Accra-Kumasi highway. An integrated speed monitoring and control program, and realigning the highway to by-pass small and medium settlements would be required as a long-term measure for the reduction of speed-related road traffic crashes, fatalities, and injuries in Ghana.     

The impact of agroforestry combined with water harvesting on soil carbon and nitrogen stocks in central Chile evaluated using the ICBM/N model

Soil organic carbon (SOC) and total nitrogen (N) stocks in an agroforestry system with water harvesting were analysed in a field experiment and the results compared with those of other crop management systems in the Mediterranean zone of central Chile. Agroforestry with water harvesting showed higher positive effects on N stocks, mainly in the upper soil layer, than the other crop management systems. However, soil analysis revealed a lack of differences between treatments, a fact that might be related mainly to the short study time (12 years) and the high spatial variability in these soil properties at the experimental site. In addition, the Introductory Carbon Balance Model that simulates N processes (ICBM/N) was evaluated for simulating trends in SOC and N stocks in the field experiment. Soil data collected between 1996 and 2008 in the field experiment and primarily literature data sets were used to test ICBM/N and its performance was evaluated by considering uncertainty in model inputs using Generalised Likelihood Uncertainty Estimation (GLUE) methodology. The GLUE estimates (5% and 95%) and measured SOC and N stocks were in satisfactory agreement. The observed SOC and N stocks were bracketed by the uncertainty bands in 70% and 80% of the simulations, respectively. Sensitivity analysis showed the model to be most sensitive to C parameters, such as the humification coefficient (h). The results of this study show that ICBM/N can be an effective tool for estimating SOC and N stocks from agroforestry combined with water harvesting systems in the Mediterranean zone of central Chile over the medium term. However, they also indicate that additional data sets are needed to redefine the parameter distributions in the model and thus to predict trends in SOC and N stocks in the future.     

蒙特卡洛分析在氯气泄漏事故环境风险评价中的应用研究

气体泄漏事故环境风险系统中存在的不确定性问题影响了定量环境风险评价结果的科学性和实用性.因此,本研究采用蒙特卡洛分析方法对氯气泄漏事故风险系统中的6个风险变量进行分析,并进一步对气体泄漏过程进行仿真模拟,得到模拟结果及其概率分布.同时,将蒙特卡洛分析结果、毒性剂量反应指标和风险受体信息在地理信息系统中进行综合分析,以个...     

闽江下游突发性水污染事故时空模拟

以闽江下游为例,基于有限元法建立闽江下游水动力模型及水质模型,通过对模型进行率定和验证,表明该模型具有较理想的模拟效果.在此基础上,利用闽江下游2004年的水文情况,模拟了突发性水污染事故中污染物的运移扩散过程.定量模拟了突发性水污染事故发生后,闽江下游不同地点处污染物到达的时间和浓度值,并对突发风险事故的影响范围、程...