“Embedded” at hire? Predicting the voluntary and involuntary turnover of new employees

Embeddedness theory has been invoked to describe factors that constrain employee turnover, such as fit with the environment, interpersonal links, and potentially sacrificed benefits. In contrast with previous assumptions that embeddedness requires considerable time to develop on the job, we extend theory by demonstrating how biographical characteristics (i.e., biodata), assessed at or before the point of hire, are related to individual's propensity to be embedded, while also showing how such characteristics predict one's future turnover likelihood. Beyond voluntary turnover, we also build embeddedness‐based theoretical explanations for involuntary turnover (i.e., terminations). To test these ideas, we conducted two studies at and before employees' point of hire, respectively: Study 1 examined how assessed biodata items of new employees relate to established embeddedness measures, whereas Study 2 linked the same biodata items assessed during the application process to employees' future involuntary, avoidable voluntary, and unavoidable voluntary turnover. Study 1 results revealed various biodata items predicted embeddedness in two distinct samples. In Study 2, results showed that biodata predicted turnover forms in unique ways. Our study highlights the utility of point‐of‐hire embeddedness propensity as a means to explain organizational exit, thereby demonstrating how organizations can use embeddedness tenets for employee recruitment and selection purposes.     

A new theory of the creation of biomethane from aluminium-containing inorganic wastes

Energy by-products from the co-combustion of municipal solid waste with coal or biomass are monitored only in terms of oxides; the amount of metallic aluminium is not determined. When these energy by-products are deposited at landfills, the alkali metal compounds in landfill bodies undergo reactions with aluminium in the presence of water. This leads to the formation of hydrogen and its possible bioconversion into methane. The article summarises the findings of the possible development of methane and hydrogen from the ashes of 11 items of typical municipal waste containing aluminium, burned in power plants, which are then landfilled. The assessment of the new information on aluminium-waste reactions in landfill bodies and the metabolism of some bacteria may give rise to a new theory of the formation of the biomethane contained in the landfill gas.     

A model of natural degradation of 17-α-ethinylestradiol in surface water and identification of degradation products by GC-MS

Over the past decade, the environment has been polluted by a wide spectrum of exogenous chemicals and environmental analysis has become one of the most progressive parts of analytical research. The aim of this work was to determine the kinetics of natural degradation, and to identify the degradation products of the massively used estrogenic drug, 17-α-ethinylestradiol. The photodegradation, oxidation and thermostability conditions were selected according to ICH requirements for pharmaceutical stability testing. A simple 72-h photodegradation study in purified water exhibited significant first-order kinetics with the kinetic constant k = 0.0303 h^?1, and degradation halftime 22.8 h. The basic halftime could be reduced to 17.1 h by the addition of sea salt, and increase in temperature. Monohydroxy, dihydroxy and dehydrogenated derivatives of ethinylestradiol with intact steroidal structure were identified as major degradation products resulting from simple photodegradation. The addition of an oxidative agent significantly accelerated the degradation rate; combined with higher temperature, the degradation halftime was reduced to 1.1 h with the first-order kinetic constant k = 0.632 h^?1. TOC analysis showed a notable decrease of organic mass (18% in 3 days) during oxidation experiments, and confirmed the degradation of steroidal structure.

     

Process safety challenges for SMEs in China

While process safety regulations and standards have been in place in western countries for more than two decades, China has only recently started to officially embrace these issues with the adoption of its Process Safety Management (PSM) regulation AQ/T 3034-2010 (SAWS, 2010). However, compliance with this regulatory framework requires substantial resources and may therefore appear too complex to be efficiently implemented by small and medium sized enterprises (SMEs) in the chemical sector. This is of particular relevance as about 99% of chemical companies in China are SMEs, accounting for more than 80% of all chemical accidents. To address this issue, additional local regulations and planning activities related to process safety have been implemented in China, including the establishment of hundreds of chemical industry parks. Some of the process safety problems faced by chemical industry parks are identified and discussed in this paper. To help solve these problems, UNEP's “Responsible Production approach for Chemical Hazards Management along the Value-Chain” is introduced in this paper and suggested as a simplified PSM approach targeted specifically at SMEs which, regardless of handling hazardous chemicals in their daily operations, may not have the knowledge or capacity to efficiently implement PSM and may not fall in the scope of the PSM regulation AQ/T 3034-2010. By introducing PSM to SMEs in a more manageable way, relevant steps can be progressively implemented by companies towards full compliance with the current regulatory framework, contributing to increased safety in chemical industry parks in China.     

Enzymatic degradation of anthracene, dibenzothiophene and pyrene by manganese peroxidase in media containing acetone

The high hydrophobicity of polycyclic aromatic hydrocarbons (PAHs) greatly hamper their degradation in liquid media. The use of an organic solvent can assist the degradative action of ligninolytic enzymes from white rot fungi. The enzymatic action of the enzyme manganese peroxidase (MnP) in media containing a miscible organic solvent, acetone (36% v/v), was evaluated as a feasible system for the in vitro degradation of three PAHs: anthracene, dibenzothiophene and pyrene. These compounds were degraded to a large extent after a short period of time (7, 24 and 24h, respectively), at conditions maximizing the MnP-oxidative system. The initial amount of enzyme present in the reaction medium was determinant for the kinetics of the process. The order of degradability, in terms of degradation rates was as follows: anthracene>dibenzothiophene>pyrene. The intermediate compounds were determined using gas chromatography-mass spectrometry and the degradation mechanisms were proposed. Anthracene was degraded to phthalic acid. A ring cleavage product of the oxidation of dibenzothiophene, 4-methoxybenzoic acid, was also observed.     

新疆雪豹种群密度监测方法探讨

2004-2010年间,前后累计270多天,新疆雪豹研究小组在新疆北塔山、阿尔泰山、昆仑山、天山东部和托木尔峰地区20多个地点(山谷),对雪豹(Uncia uncia)的痕迹进行了全面调查,共计完成150多条样线,总长度接近190 km,痕迹数平均为1～3个·km-1.记录到的痕迹有粪团、嗅痕(气味标记)、足迹链、刨痕(刨坑)、爪痕、卧迹、毛发、尿迹、血迹、剩余食物(动物尸体)和吼声等.通过痕迹学的分析,初步掌握雪豹的领域范围、分布规律和相对密度.之后开展了红外相机拍摄、雪豹食物资源普查、市场毛皮调查、贸易通道调查、杀戮案件搜集、民间问卷调查、非政府组织(NGO)社区服务与牧业冲突调研等工作.同期布设红外相机36台,约2094个照相日,计50 256 h,回收胶卷71个,回收清晰雪豹照片32张,平均拍摄率或"捕获率"(capture rate)达1.53%.确定在托木尔峰250 km2范围内有5～8只雪豹活动,密度为2.0～3.2只·(100 km2)-1.在比较分析各种监测结果的基础上,讨论了新疆雪豹种群密度不同监测方法的优点与局限性.     

Variation in sperm morphometry and sperm competition among barn swallow (Hirundo rustica) populations

Spermatozoa vary greatly in size and shape among species across the animal kingdom. Postcopulatory sexual selection is thought to be the major evolutionary force driving this diversity. In contrast, less is known about how sperm size varies among populations of the same species. Here, we investigate geographic variation in sperm size in barn swallows Hirundo rustica, a socially monogamous passerine with a wide Holarctic breeding distribution. We included samples from seven populations and three subspecies: five populations of ssp. rustica in Europe (Czech, Italy, Norway, Spain, and Ukraine), one population of ssp. transitiva in Israel, and one population of ssp. erythrogaster in Canada. All sperm traits (head length, midpiece length, tail length, and total length) varied significantly among populations. The variation among the European rustica populations was much lower than the differences among subspecies, indicating that sperm traits reflect phylogenetic distance. We also performed a test of the relationship between the coefficient of between-male variation in total sperm length and extrapair paternity levels across different populations within a species. Recent studies have found a strong negative relationship between sperm size variation and extrapair paternity among species. Here, we show a similar negative relationship among six barn swallow populations, which suggests that the variance in male sperm length in a population is shaped by the strength of stabilizing postcopulatory sexual selection.     

Memory for the spatial layout of the everyday physical environment: Factors affecting rate of acquisition

That a memory representation of the spatial layout of a large-scale environment may be acquired very fast was shown in two experiments in which subjects (48 undergraduates and high-school students) were taken on tours through a residential area with which they were unfamiliar. Memory for the path traversed was almost perfect after the first trial, as indicated by almost perfect recall of the order in which a number of designated landmarks had been passed. Memory for the locations of the same landmarks appeared to reach an asymptotic level after the second of three trials. The memory representation of the locations were however not perfectly accurate, thus the asymptotic level might have been an acquisition plateau. The rate of acquisition was slightly faster for subjects driven in a car slowly through the area than for those who walked the same path. Men tended to improve slightly faster than women if they were driven by car but there were no other sex differences. Finally, the acquired memory representation appeared to be resistant to forgetting. Re-learning after a one-week retention interval was faster and rate of learning was not negatively affected whether the trials were massed or distributed with one week in between. The results are discussed in terms of hypotheses concerning the order in which different types of information about spatial layouts (landmarks, paths, and locations) are acquired. The bearing of the results on the question of why memory representations of the spatial layout are often found to be distorted is also discussed.