渤海中部营养盐季节变化及限制统计分析

根据2013年7月（夏季）,11月（秋季）和2014年5月（春季）渤海中部海域营养盐数据以及温盐等数据,以浮游植物对营养盐的吸收阈值和化学计量关系为判断标准,对研究海域营养盐分布、限制状况以及季节变化特征进行分析,结果表明：调查海域内各营养盐组分变化均呈现明显季节性特征,表现为夏季低秋季上升春季下降的趋势.夏季受冲淡水影响,海水存在层化现象,溶解无机氮（DIN）、PO₄^3--P和SiO₃^2--Si含量分别为（10.33±7.75）、（0.05±0.03）和（3.94±3.19）μmol/L,DIN/P较高,Si/DIN远低于1,其中表层和10m层存在P和Si限制站位分别达93%、93%和40%、20%,限制状况严重.秋季受底层沉积物扰动再悬浮及营养盐矿化释放等因素影响,各种营养盐含量迅速上升,DIN、PO₄^3--P和SiO₃^2--Si含量为（16.44±6.51）、（0.54±0.20）和（16.94±6.37）μmol/L,分别升高了1.6、10.8和4.3倍,垂向分布差异较小,且仅存在P潜在限制现象.春季由于陆源输入相对较少,同时受浮游植物吸收等因素影响,各营养盐含量急剧下降,DIN、PO₄^3--P和SiO₃^2--Si含量分别为（9.04±8.06）、（0.06±0.04）和（2.47±1.90）μmol/L,分别降低了45%、89%和85%,其中部分站位PO₄^3--P和SiO₃^2--Si含量低于阈值,在表层和10m层海水中存在P和Si限制站位分别达70%、65%和55%、50%,对海域内硅藻作为优势种的浮游植物生长和初级生产力产生影响.     

PRECIPITATION DISTRIBUTION IN COASTAL BRITISH COLUMBIA1

ABSTRACT: The spatial distribution and the temporal and spatial variation of the annual, seasonal, and monthly precipitation in two mountainous watersheds in southwestern British Columbia, Canada, have been analyzed using a detailed database for 1971–1990 in the Capilano and Seymour watersheds. The analysis showed that the precipitation increases up to the mid-position of the watersheds, and then either levels off or decreases. Precipitation on mountain slopes and in the valley at the same distance from the beginning of the slope is similar, and the barrier height is identified as the dominant parameter which influences the precipitation distribution. The temporal variation of the precipitation is the smallest at the mid-position of the watersheds. This variability is the least in the fall and winter and largest in the summer. Correlation between the precipitation accumulations at various stations is large, ranging from 0.80 for the wet period of October-March to 0.65 for the dry period of April-September for distances less than 32 km. Comparison with other studies and the analyses of precipitation and runoff data from coastal British Columbia showed that the results of this study are perhaps general and thus transferable to similar areas in the coastal Pacific Northwest.     

Do racial differences exist in second-trimester maternal hCG levels? a study of 23 369 patients

In Down syndrome screening by maternal serum human chorionic gonadotropin (hCG) determination at 15, 16, 17, and 18 weeks of gestation, we prospectively examined 23 369 sera from white (21 549), North African (970), black African (525), and Asian (325) patients. When expressed as multiples of the median (MOM), no difference was observed between white, North African, and black African patients. However, higher serum hCG concentrations were noted in Asians, for whom we therefore recommend correction of hCG values before calculation of the risk of Down syndrome.     

Comparison of atmospheric concentrations of currently used pesticides between urban and rural areas during intensive application period in Alsace (France) by using XAD-2® based passive samplers

XAD-2® passive samplers (PAS) have been exposed simultaneously for 14 days on two sites, one rural and one urban, situated in Alsace (East of France) during intensive pesticides application in agriculture (between March and September). PAS have been extracted and analyzed for current-used pesticides and lindane with an analytical method coupling accelerated solvent extraction (ASE), solid-phase microextraction (SPME) and GC/MS/MS. Results show the detection of pesticides is linked to the period of application and spatial and temporal variabilities can be observed with these PAS during the selected sampling period. The spatial and temporal variability is comparable to the one previously observed by comparing data obtained with PAS with data from Hi.-Vol. samplers in an urban area. Sampling rates were calculated for some pesticides and values are comparable to the data already available in the literature. From these sampling rates, concentrations in ng m^?3 of pesticides in PAS have been calculated and are in the same order of magnitude as those obtained with Hi.Vol. sampling during the same period of time.     

Against Oversimplifying the Issues on Relocating Turtle Eggs

Translocating sea turtle eggs at risk from high tides to safer places is one of the most widely undertaken conservation measures on behalf of these species. Recent research work has shown that individual female turtles differ in their nest-site preferences. If more of the nests saved by translocation come from turtles with tendencies to lay near the water, might this perhaps interfere with natural selection? This possibility adds to the controversy already surrounding relocation of turtle nests.     

STREAM NITRATE-N LOADS IN RELATION TO VARIATIONS IN ANNUAL AND SEASONAL RUNOFF REGIMES1

ABSTRACT: The calculation of stream nutrient loads from a sampling period of one year or, at most, a few years may provide an inaccurate estimate of average seasonal or annual loads due to considerable year-to-year variations in hydrological regime. The number of years of record required to give a reliable estimate of long-term average NO₃-N loads was analyzed for E. Duffin Creek and the Nottawasaga River in Ontario, Canada. Nitrate load rating relationships were used in combination with a continuous stream discharge record for 22 years (E. Duffin Creek) and 34 years (Nottawasaga River) to simulate long-term seasonal and annual variation in NO₃.N loads. The errors involved in calculating average loads were examined by comparing the loads derived from sampling periods of one or more consecutive years duration with the estimated long-term average load for the two rivers. Annual NO₃-N loads for a single year deviated from the long-term average load by ± 20 to 53 percent in 8 out of 22 years in E. Duffin Creek and in 13 of 34 years in the Nottawasaga River. Six consecutive years of record would be required for both rivers to ensure that an error of > ± 20 percent would occur in only 5 percent of these observation periods. February-April NO₃-N loads for a single year could deviate by up to +90 percent or -61 percent from the long-term average spring period load for the two rivers. A sampling period of at least 6–7 years would be needed to estimate average NO₃-N loads for the spring runoff season with an error <± 20 percent.     

中国科技人才资源区域差异与类型

中国科技人才资源的地区和部门分布具有明显的区域差异.在三大地带间、地区内和各省市间差异程度不同且有扩大趋势,在三个重要部门中配置也表现出明显的地域差异.根据科技人才资源赋存状况及部门配置的区位熵值,将各省市区分成5种类型:科技人才资源高度型、中高度型、中度型、中低度型、低度型,这些区域类型与我国的区域经济发展格局相适应.     

我国中西部典型城市PM2.5中痕量金属的时空分布特征和健康影响

为研究我国中西部地区大气细颗粒物中的痕量金属区域分布、季节分布特征以及健康风险,在西安、乌鲁木齐、洛阳以及兰州四城市布点采样,利用ICP-AES（电感耦合等离子体原子发射光谱仪）测定了PM_2.5中9种痕量金属（V、Cr、Cd、Mn、Ni、Cu、Zn、As、Pb）的质量分数.结果表明：在痕量金属的时空分布特征方面,各城市主导痕量金属存在差异,西安、乌鲁木齐、洛阳以及兰州的主导痕量金属为Mn、Zn、Pb、Pb,除了主导痕量金属,对于单个金属,其空间分布及季节分布都存在差异;利用分歧系数法分析了城市间颗粒物中痕量金属的组成,洛阳与其他城市颗粒物中痕量金属的CD值在0.4左右,表明洛阳与各城市颗粒物中痕量金属的组成有很大差异,而西安与乌鲁木齐、兰州两个城市的CD值几乎都小于0.2,则他们组成相似;健康风险评结果显示,颗粒物PM_2.5中的痕量金属Cr对成年人有着显著的致癌和非致癌风险,而且Cd、As对4个城市居民的致癌风险是显著的,Ni对其致癌风险不显著.长期处于该研究环境,对人体健康存在一定健康威胁.此外痕量金属对人体的健康风险也具有季节性,所有痕量金属ILCR值都高于10^-6,尤其是As、Cd、Cr的致癌风险超过了安全水平（10^-4）,尤其是Cr和As春冬季的致癌风险最高.     

It is time for justice: How time changes what we know about justice judgments and justice effects

Organizational justice is an important determinant of workplace attitudes, decisions, and behaviors. However, understanding workplace fairness requires not only examining what happens but also when it happens, in terms of justice events, perceptions, and reactions. We organize and discuss findings from 194 justice articles with temporal aspects, selected from over a thousand empirical justice articles. By examining temporal aspects, our findings enrich and sometimes challenge the answers to three key questions in the organizational justice literature relating to (i) when individuals pay attention to fairness, including specific facets, (ii) how fairness judgments form and evolve, and (iii) how reactions to perceived (in)justice unfold. Our review identifies promising avenues for empirical work and emphasizes the importance of developing temporal theories of justice. Copyright © 2014 John Wiley & Sons, Ltd.     

Effects of spatial and temporal scales on cultural services valuation

The monetary valuation of ecosystem services has proved to be a powerful tool for influencing management decisions, as it can be used to quantify the relative importance of various ecosystem functions. However, these valuation methods are rarely implemented with adequate care; in particular, they do not consider spatial and temporal variations in the services offered and demanded. This paper examines the effect of heterogeneity on the valuation of cultural services offered by the Doñana natural protected area in Spain. We apply the zonal travel cost method at various spatial scales, and the individual travel cost method at various temporal scales. We conclude that economic valuation techniques must account for spatial and temporal heterogeneity if they are to provide accurate and realistic information.