Trace-metal contamination in the glacierized Rio Santa watershed,Peru

The objective of this research is to characterize the variability of trace metals in the Rio Santa watershed based on synoptic sampling applied at a large scale. To that end, we propose a combination of methods based on the collection of water, suspended sediments, and riverbed sediments at different points of the watershed within a very limited period. Forty points within the Rio Santa watershed were sampled between June 21 and July 8, 2013. Forty water samples, 36 suspended sediments, and 34 riverbed sediments were analyzed for seven trace metals. The results, which were normalized using the USEPA guideline for water and sediments, show that the Rio Santa water exhibits Mn concentrations higher than the guideline at more than 50% of the sampling points. As is the second highest contaminating element in the water, with approximately 10% of the samples containing concentrations above the guideline. Sediments collected in the Rio Santa riverbed were heavily contaminated by at least four of the tested elements at nearly 85% of the sample points, with As presenting the highest normalized concentration, at more than ten times the guideline. As, Cd, Fe, Pb, and Zn present similar concentration trends in the sediment all along the Rio Santa.The findings indicate that care should be taken in using the Rio Santa water and sediments for purposes that could affect the health of humans or the ecosystem. The situation is worse in some tributaries in the southern part of the watershed that host both active and abandoned mines and ore-processing plants.     

Diurnal vertical migration of Cochlodinium polykrikoides during the red tide in Korean coastal sea waters

The diurnal vertical migration of Cochlodinium polykrikoides (C. polykrikoides), which caused a red tide in the Korean coastal waters of the East Sea/Sea of Japan in September 2003, was examined by determining the time-dependent changes in the density of living cells in relation to the depth of the water column. The ascent of this species into the surface layer (depth of water 2 m) occurred during 1400-1500. The descent started at 1600 and a high distribution rate (86%) at 15-20 m was observed at 0300. During the ascent, the cells were widely distributed at each depth level from 0600 hr and at 0800-1100, the cells were primarily distributed in the middle layer (0-6 m). The concentration of dissolved inorganic nitrogen was generally < or = 2.86 micromol l(-1), but at 1400-1500, the concentration in the surface layer reduced to < or = 0.14 micromol l(-1). Moreover, the concentration gradually increased as the depth increased to > or = 5 m. These results showed that the nutrient-consumption rate associated with the proliferation of C. polykrikoides during a red tide is more influenced by the inorganic-nitrogen resources ratherthan the inorganic-phosphorus compounds.     

Integrating GIS and high resolution orthophoto images for the development of a geomorphic shoreline classification and risk assessment—a case study of cliff/bluff erosion along the Bulgarian coast

This paper demonstrates the effectiveness of integrating GIS and modern spatial data for the development of a detailed geomorphic classification of the Bulgarian Black Sea coast. This classification is important for the precise measurement of various natural and technogenous (engineered) coastline types and serves as a basis for identification of the areas with high exposure to different coastal hazards. To illustrate potential uses of this simple methodology, a map of the potential coastal erosion/cliff retreat hazard for the Bulgarian coast was produced from this GIS database. Several types of data were used: high resolution orthophoto, topographical maps in 1:5,000 scale and geological maps. Geomorphic classification utilized both geomorphological and engineering criteria. A total of 867 segments were delineated along the coast. Four hundred sixty five were classified as natural landforms (cliffs, beaches, river mouths) with a total length of 362,62 km and 402 were indicated as technogenous segments (port and coast-protection structures, artificial beaches) with a total length of 70 km. Based on the geologic materials present at each segment and cliff height, the cliffed portions of the Bulgarian coast were classified for expected erosion rates, and therefore, hazard vulnerability: low hazard (volcanic type cliff); moderate hazard (limestone type cliff) and high hazard (loess and clayey types cliff). This “predictive model” was then compared to a previously published field study of coastal erosion rates to validate the model. As a result, a new high quality, but qualitative data for Bulgarian coastal bluff/cliff erosion were obtained, incorporated and analyzed in GIS.     

Do organizations spend wisely on employees? Effects of training and development investments on learning and innovation in organizations

The present study examines the effects of training and development on organizational innovation. We specifically suggest that the training and development investments of an organization affect its innovative performance by promoting various learning practices. We empirically tested our hypothesis by using time‐lagged, multi‐source data collected from 260 Korean companies that represent diverse industries. Our analysis showed that corporate expenditure for internal training predicts interpersonal and organizational learning practices, which, in turn, increase innovative performance. The data also revealed that the positive relationship between interpersonal and organizational learning practices and innovative performance is stronger within organizations that have stronger innovative climates. By contrast, investment in employee development through financial support for education outside an organization poses a significant negative effect on its innovative performance and no significant effect on learning practices. The present study provides a plausible explanation for a mechanism through which the investment of an organization in employees enhances its innovative performance. Copyright © 2013 The Authors. Journal of Organizational Behavior published by John Wiley & Sons, Ltd.     

超高效液相色谱/三重四极杆质谱联用(ACQUITY UPLC/Xevo TQ-S)检测蜂花粉中吡虫啉残留量

正在分析复杂环境样品中的痕量污染物时,通常会受到基质的严重干扰,使得在进行亚ng·g-1浓度水平检测时,所用仪器面临着必须满足灵敏度要求的挑战.杀虫剂暴露会对蜂群产生致死和亚致死效应,若要监控这些效应带来的影响则需要对蜜蜂和蜂产品中的杀虫剂水平进行可靠定量.某地区使用吡虫啉杀虫剂来应对昆虫的侵害,我们对该地区的蜜蜂样本及花粉产品进行了吡虫啉残留分析,花粉中平均含有20%蛋白质和6%总脂肪,并且还含有大量的维生素、脂肪酸、     

Complexity,continuity and change: livelihood resilience in the Darfur region of Sudan

Darfur farming and pastoralist livelihoods are both adaptations to the environmental variability that characterises the region. This article describes this adaptation and the longer‐term transformation of these specialised livelihoods from the perspective of local communities. Over several decades farmers and herders have experienced a continuous stream of climate, conflict and other shocks, which, combined with wider processes of change, have transformed livelihoods and undermined livelihood institutions. Their well‐rehearsed specialist strategies are now combined with new strategies to cope. These responses help people get by in the short term but risk antagonising not only their specialist strategies but also those of others. A combination of factors has undermined the former integration between farming and pastoralism and their livelihood institutions. Efforts to build resilience in similar contexts must take a long‐term view of livelihood adaptation as a specialisation, and consider the implications of new strategies for the continuity and integration of livelihood specialisations.     

Fluorescence detection and determination of patulin by thin-layer chromatography of its aniline imine.

A sensitive and simple procedure is descrobed for the analysis of the mycotoxin patulin. The method involves extraction of patulin from the sample, silica gel column chromatographic clean-up, preparation of the aniline imine, thin-layer chromatographic separation on silica gel, hydrogen chloride hydrolysis of the imine, and fluorophore formation from the liberated aniline with fluorescamine. A linear calibration curve was obtained for the 10-100 ng range and the limit of detection was 5 ng. Recoveries of patulin from samples of apple juice spiked at 50-500 ppb were quantitative.