陕西潼关南寨子遗址人口的平均预期寿命与死亡模式

作为社会存在和发展的基础和主体,人口因素在人类文明发展中起着重要作用.我们通过编制生命表,对陕西潼关南寨子遗址4个墓葬出土的人骨进行古人口学分析,计算出关中平原东部地区仰韶文化中期人口的平均预期寿命为27.8岁,高出我国西北、东北地区和太湖流域新石器时期的人口平均预期寿命约8岁.而与山东沿海地区大汶口文化时期的王因遗址...     

高氯酸钠对斑马鱼胚胎的毒性效应

采用斑马鱼胚胎发育技术方法研究高氯酸钠对斑马鱼胚胎的急性毒性效应,配制一系列高氯酸钠的浓度,对受精1h的胚胎进行染毒暴露,最后对斑马鱼胚胎的心率,孵化率,死亡率,畸形率进行统计分析。研究结果显示,高氯酸钠(NaClO4)浓度的增加,斑马鱼胚胎的心率和孵化率降低、死亡率和畸形率增加。斑马鱼48hpf的胚胎心率高浓度组比对照组下降了35%;72 h的孵化率由对照组的88%降低到高浓度组的36%;144 h的死亡率由对照组的5%增加到72%;144 h的畸形率由对照组的2%增加到91%,主要畸形表现为心包囊肿(PE),脊柱弯曲(AM),鱼鳔缺失(SBD)等。结果表明,高浓度的高氯酸钠(NaClO4)对斑马鱼胚胎发育有明显的剂量效应作用。     

Mortality from road traffic accidents in a rapidly urbanizing Chinese city: A 20-year analysis in Shenzhen, 1994–2013

Objective: This study aimed to describe the trends of motorization and mortality rates from road traffic accidents and examine their associations in a rapidly urbanizing city in China, Shenzhen.

Methods: Using data from the Shenzhen Deaths Registry between 1994 and 2013, we calculated the annual mortality rates of road traffic accidents, in addition to the age- and sex-specific mortality rates and their annual percentage changes (APCs) for the period of 2000–2013. We also examined the associations between mortality rate of road traffic accidents and traffic growth with Spearman's rank correlation analysis and a log-linear model derived from Smeed's law.

Results: A total of 20,196 deaths due to road traffic accidents, including 14,391 (71.3%) male deaths and 5,805 (28.7%) female deaths, were recorded in Shenzhen from 1994 to 2013. The annual mortality rates in terms of deaths per population and deaths per vehicle changed in similar patterns, demonstrating an increase since 1994 and peaking in 1997, followed by a steady decrease thereafter. The decrease in mortality was faster in individuals aged 20 year or older compared to those younger than 20 years. The mortality rates in term of deaths per population were positively correlated with the total number of vehicles per kilometer of road but negatively correlated with the motorization rate in term of vehicles per population. The estimated model for deaths due to road traffic accidents in relation to the total population and the number of registered vehicles was ln (deaths/10,000 vehicles) = ?1.902 × ln (vehicles/population) ? 1.961. The coefficient was statistically significant (P < .001) and the coefficient of determination was 0.966, indicating a good model fit.

Conclusions: We described a generally decreasing trend in the mortality rates of road traffic accidents in a rapidly urbanizing Chinese city based observations in the 20-year period from 1994 to 2013. The decreased mortality rate may be explained by the expansion of road network construction, improved road safety regulations and management, as well as more accessible ambulance services in recent years. Nevertheless, road traffic accidents remain a universal problem of great public health concern in the whole population.     

Road effects on abundance and fitness of Galápagos lava lizards (Microlophus albemarlensis)

Vehicle collisions with wildlife have the potential to negatively impact species everywhere roads divide natural habitats; this is especially true in areas where roads are a recent addition to the landscape (e.g., in the last decade) and/or where expansion of a road network is underway. This study addresses the impact of traffic fatalities on lava lizards, Microlophus albemarlensis, on the island of Santa Cruz, Galápagos. The main road bisecting the island north to south was added to the island beginning in 1974 but not fully paved until 2000. We assessed impacts occurring due to traffic and vehicle speeds on the island. This study adds impacts to lizard populations to those conducted on birds on Santa Cruz, providing a means to create multi-species recommendations. To quantify impacts to lizard populations, we assessed lizards on randomly chosen transects perpendicular to the road. We used Poisson regression to analyze those data and found a 30% increase in lizard abundance per 100 m distance from the road across vegetation zones. We compared incidence of prior tail loss of road-killed lizards and live animals to comment on additional energetic costs of occupying near-road territories. Tail condition could not be assessed in some road-killed lizards; among those that we could assess, 29% showed evidence of prior tail loss. That rate declined to apparent baseline conditions of only 1% beyond 200 m from the road. By traveling the length of the 40-km road, we identified hot spots for fatalities of both lizards and birds to provide necessary information for developing management and remediation strategies. We offer guidance on Best Management Practices, such as testing overpasses, fencing and underpasses, which might reduce vehicle impacts to lizards from drivers on the current road. This information is essential because of a planned increase in the Santa Cruz road network in areas where lava lizards are most abundant.     

Sibling aggression, hatching asynchrony, and nestling mortality in the black kite (Milvus migrans)

In siblicidal species, hatching asynchrony could act to reduce sibling rivalry or promote the death of last-hatched chicks. The pattern of hatching asynchrony was experimentally altered in the black kite Milvus migrans. Hatching asynchrony in control broods was intermediate between those of experimentally synchronised and asynchronised broods. Sibling aggression and wounds on the chicks were more commonly observed early in the nestling period and in synchronous nests. Serious injuries were observed on last-hatched chicks in asynchronous nests, as were observations of intimidated or crushed chicks. Sibling aggression was related to food abundance, but some chicks died at an early age in nests with abundant food (cainism). Cainism was more commonly found in asynchronous nests. For species with facultative siblicide, moderate hatching asynchrony could be a compromise between reducing sibling rivalry and avoiding large size differences between sibs that would result in cainism. Female black kites preferentially fed the smallest chicks and exhibited behaviours to reduce sibling aggression, contrary to observations in other siblicidal species. In a highly opportunistic forager such as the black kite, a strategy may exist to protract the life of all the chicks in the brood, waiting for unpredictable situations of food overabundance. This would induce the appearance of a parent-offspring conflict over brood reduction, reflected in the existence of a possible anticipated response by some of the chicks (cainism) and in the appearance of special behaviours by the parents to selectively feed smaller chicks or reduce sibling aggression. In this facultatively siblicidal species, cainism does not seem to be the final stage of an evolutionary trend favouring the raising of high-quality chicks, but a manifestation of a parent-offspring conflict over brood size. Received: 9 March 1998 / Accepted after revision: 8 August 1998     

Earthquake mortality in Pakistan

A strong earthquake, measuring 7.6 on the Richter scale, hit northern Pakistan on 8 October 2005, causing massive destruction, including an official death toll of 73,276. Four cross-sectional surveys were performed in late 2005 to assess mortality before the event, on the day, and subsequently. Two surveys were community-based and two were situated in camps for internally displaced persons. Crude mortality rates were low in the 3.5 months preceding the earthquake (less than 0.1 deaths per 10,000 per day) and slightly higher in the six-to-eight weeks after the earthquake (ranging from 0.10–0.43 per 10,000 per day). On 8 October 2005, approximately two per cent of the population in one community survey died and around five per cent in the other three surveys. Children less than five years and adults more than or equal to 50 years tended to have a higher risk of mortality on the day of the disaster. These results corroborate the high mortality caused by the earthquake.     

地质封存CO_2泄漏对蚯蚓的毒性效应

二氧化碳捕集与封存技术(CO_2 capture and storage, CCS)是当前国际上公认的CO_2减排的有效措施,但封存在地下的CO_2仍然因为各种不稳定因素存在泄漏风险,对土壤环境及土壤生态系统产生威胁。选择赤子爱胜蚓为研究对象,通过模拟高浓度CO_2对蚯蚓形态与生理变化的影响,探究CCS泄漏所产生的土壤高浓度CO_2对蚯蚓的毒性效应。研究表明,土壤高浓度CO_2使蚯蚓出现生殖环带肿大、尾部串珠以及断尾等外部形态变化,皮肤和刚毛受到损伤并且表皮发生褶皱等现象;随着CO_2浓度的增加以及暴露时间的延长,蚯蚓的死亡率不断增加,土壤高浓度CO_2对蚯蚓的7 d和14 d半致死浓度分别为26.39%和17.78%;蚯蚓体腔细胞溶酶体中性红保留时间(NRRT)减少。因此,蚯蚓有望作为监测CO_2泄漏的指示生物,NRRT可作为识别CO_2泄漏的敏感指标。     

Arsenic and Mn levels in Isaza (Gymnogobius isaza) during the mass mortality event in Lake Biwa, Japan

The present study measured the concentrations of 25 elements (Li, Mg, V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb and Bi) in the whole body of Isaza which is an endemic fish species to Lake Biwa, Japan, and compared the values in the specimens from the mass mortality Isaza (MMI) and normal fresh Isaza (NFI). The mean levels of Mn and total As (T-As) were relatively higher in MMI than in NFI. In the T-As, highly toxic inorganic As was detected in MMI. Moreover we found Mn and As concentrations in surface sediment were extremely high and temporally increased. From all these results, we could infer that the dissolution of Mn and As from surface sediment of Lake Biwa might have been one of the cause for the mass mortality of Isaza.     

Demographic Parameters of the Tartarian Roe Deer Population in the Transural Region and the Main Factors Determining Them

The demographic parameters (sex and age structure, fecundity, and population growth) and the main environmental factors (legal hunting and poaching, predators, weather, and food supply) affecting the structure and dynamics of the large Tartarian roe deer (Capreolus pygargus Pall.) population of Kurgan oblast were studied. The question of the conformity between the population size and the carrying capacity of its range is considered.     

Cross-sectional survey methods to assess retrospectively mortality in humanitarian emergencies

Since the rates and causes of mortality are critical indicators of the overall health of a population, it is important to evaluate mortality even where no complete vital statistics reporting exists. Such settings include humanitarian emergencies. Experience in cross-sectional survey methods to assess retrospectively crude, age-specific, and maternal mortality in stable settings has been gained over the past 40 years, and methods appropriate to humanitarian emergencies have been developed. In humanitarian emergencies, crude and age-specific mortality can be gauged using methods based on the enumeration of individuals resident in randomly selected households—frequently referred to as a household census. Under-five mortality can also be assessed through a modified prior birth history method in which a representative sample of reproductive-aged women are questioned about dates of child births and deaths. Maternal mortality can be appraised via the initial identification of maternal deaths in the study population and a subsequent investigation to determine the cause of each death.