Individual growth need strength as a moderator of the relationship of worker satisfaction and job attitudes to worker productivity.

The experimental research showed that the worker satisfaction-productivity and the worker job attitudes-productivity relationships were stronger for the individuals who had exhibited a higher growth need strength (GNS) than the subjects with a lower GNS in a repetitive production task enriched by the provision of production standards and feedback. Under high GNS, the correlation coefficient values between worker satisfaction and productivity in terms of quantity output were found to be statistically significant, whereas none of the values were significant under low GNS. The correlation coefficient values between worker job attitudes and productivity in terms of both quantity and quality output were significant under high GNS, whereas under low GNS none of the values were significant.     

Assigned and participative production standards and feedback affecting worker productivity in a repetitive production task

The main objective of this research was to determine the effects of assigned and participative standards in conjunction with feedback on worker productivity in a repetitive production task. An assigned hard standard and feedback was significantly better than a participative standard and feedback in terms of quality output but no significant difference in quantity output was found between them. Thus from the overall worker productivity viewpoint, the former condition was superior to the latter condition. Both conditions provided a significant improvement in worker productivity. The percentage increases in quantity and quality output for the assigned hard standard and feedback condition were 12% and 7%, respectively, compared to the control group. The assigned normal standard and feedback had a significant positive impact on quantity output but no significant effect was found in terms of quality output.     

Attitudes of Dairy Farmers toward Cow Welfare in Relation to Housing,Management and Productivity

ABSTRACT

The quality of stockmanship contributes to the human–animal relationship, animal welfare and productivity. Attitudes can affect the way farmers treat their animals, the environment they provide the animals with, and even their own job satisfaction through the feedback received from the animals. Farmers' perceptions of animals have also been shown to have an impact on productivity. We investigated 161 Finnish dairy farmers' attitudes toward improving animal welfare through an attitude questionnaire that used the Theory of Planned Behavior as a theoretical framework. The theory states that personal attitude, subjective norms, and perceived behavioral control, together shape an individual's behavioral intentions and behaviors. To study the relationship between attitudes, animal welfare, and milk production, we used environment-based animal welfare indicator data consisting of categorized housing and management parameters, and mean milk production data. Non-parametric partial correlation analyses and regression analyses revealed that perceiving the measures to improve animal welfare to be important and easy were positively, although weakly, related to higher animal welfare standards/indicators, while no connection with production was established. Contrary to our expectations, sources of subjective norms, such as an agricultural adviser, were mostly negatively linked with animal welfare indicators and even with production. The farmers considered taking care of their own well-being as the most important way of improving animal welfare, and intending to do so was weakly but positively linked with animal welfare indicators. Any causal relationships, however, cannot be derived from the data.     

Larger laboratory colonies consume proportionally less energy and have lower per capita brood production in Temnothorax ants

Colony size can affect individual- and colony-level behavioral and physiological traits in social insects. Changes in behavior and physiology in response to colony growth and development can affect productivity and fitness. Here, we used respirometry to study the relationship between colony size and colony energy consumption in Temnothorax rugatulus ants. In addition, we examined the relationship between colony size and worker productivity measured as per capita brood production. We found that colony metabolic rate scales with colony size to the 0.78 power and the number of brood scales with the number of workers to the 0.49 power. These regression analyses reveal that larger ant colonies use proportionally less energy and produce fewer brood per worker. Our findings provide new information on the relationships between colony size and energetic efficiency and productivity in a model ant genus. We discuss the potential mechanisms giving rise to allometric scaling of metabolic rate in ant colonies and the influence of colony size on energy consumption and productivity in general.     

Inter-ethnic coexistence in Israeli plants: the job experiences and attitudes of Arab and Jewish workers

Through personal interviews, we examine the job experiences and attitudes of Arab and Jewish workers sharing the same work site in five manufacturing facilities. We find that Arabs and Jews differ in terms of demographic, job status, and job treatment factors, as well as in levels of job satisfaction. Using hierarchical multiple regression analyses, we determine that average Arab-Jewish differences in job satisfaction are not related to generic racial/ethnic differences. Rather, group disparities in job satisfaction primarily derive from differences in worker perceptions of their environment as well as in the nature of inter-ethnic work relations. Our results suggest employer efforts to establish a more supportive work environment and the promotion of positive cross-ethnic relationships at work may reduce the Arab-Jewish job satisfaction gap.     

Recruitment and selection of workers in Israel: The question of disparate impact

Like employers elsewhere, Israeli firms rely on an extensive variety of mechanisms to recruit and select job applicants. Some of these recruitment sources such as word‐of‐mouth referrals, reliance on local employment exchanges, and newspaper advertisements limit information on job openings to Jewish workers, and/or discourage Arab workers who are citizens of Israel from applying. Where Israeli Arab workers do succeed in identifying and applying for job vacancies, their chances of employment are disproportionately impaired by intensive employer use of such selection factors as the personal interview, experience, residency, and army service requirements. Currently the Israeli legal system permits employers to use recruitment and selection criteria which, although neutral on their face, have a discriminatory effect on Arab workers. To provide equal employment opportunity for Israeli Arab workers, Israeli policy should challenge recruitment policies and techniques which reach only a limited segment of the labour force. Similarly, selection criteria shown to have a significantly detrimental effect on Arab hiring rates should be prohibited in the absence of evidence that they are job related. Requiring that standards be affirmatively related to considerations of efficiency and productivity would benefit the Israeli Arab worker, promote the best interest of the employer, and would be reflective of principles of social justice on which basis the State of Israel was founded.     

Significant reproductive skew in the facultatively polygynous ant Pheidole pallidula

Reproductive skew - the extent to which reproduction is unevenly shared between individuals in a social group - varies greatly between and within animal species. In this study, we investigated how queens share parentage in polygynous (multiple queen) colonies of the Mediterranean ant Pheidole pallidula. We used highly polymorphic microsatellites markers to determine parentage of gynes (new queens), males and workers in P. pallidula field colonies. The comparison of the genotypes of young and adult workers revealed a very low queen turnover (less than 2%). The first main finding of the study of reproductive skew in these colonies was that there was a significant departure from equal contribution of queens to gyne, male and worker production. Reproductive skew was greater for male production than for queen and worker production. There was no relationship between the magnitude of the reproductive skew and the number of reproductive queens per colony, their relatedness and the overall colony productivity, some of the factors predicted to influence the extent of reproductive skew. Finally, our study revealed for the first time a trade-off in the relative contribution of nestmate queens to gyne and worker production. The queens contributing more to gyne production contributed significantly less to worker production.     

A comparison of worker exposure to inhalable and total dust, inorganic arsenic, and borates using two types of particulate sampling assemblies in a borate mining and processing facility

This study describes a comparison of worker exposure to total and inhalable dust, inorganic As, and borates using two types of particulate sampling assemblies as part of a comprehensive industrial hygiene evaluation in a borate mining and processing facility. Employees were segmented into similar exposure groups (SEG) based on work location within the facility, job classification, and type of chemical agent. Approximately 10% of the employees from each SEG wore two personal sampling devices simultaneously for the purpose of collecting total and inhalable particulate fractions using a closed face, 37-mm mixed cellulose ester matched-weight filters (MMW), and Institute of Occupational Medicine (IOM) sampling assembly. Sample results indicated that the IOM concentrations were consistently higher than the corresponding MMW concentrations for all three agents. An analysis was performed to investigate a relationship between MMW and IOM. The data revealed correlation coefficient values of 0.72, 0.82, and 0.84 for total dust (n = 197), inorganic As (n = 137), and borates (n = 194), respectively. These positive correlation coefficients indicate that the IOM and MMW measurements are consistent with each other, and can be used for predicting exposure levels. The total dust and borate large mean ratios should be considered in developing inhalable fraction-based regulatory standards.     

The relationship between job satisfaction and job factors in industrial work design: a case study of the automotive industries in Malaysia

A survey was conducted to investigate the relationship between job satisfaction and job factors that affect work design in two automotives manufacturing companies in Malaysia. A set of multiple choices questionnaires was developed and data were collected by interviewing the employees at the production plant. Hundred and seventy male subjects between the ages of 18 to 40 years with the mean age of 26.8 and SD of 5.3 years and mean work experience of 6.5 and SD of 4.9 years took part in the survey. The survey focused on job factors, i.e. skill variety, task identity, task significance, autonomy and feedback. The results support the previous findings that job factors are significantly correlated to job satisfaction. Furthermore, it also highlights the significant influence of age, work experience and marital status.     

Breeding behaviour, relatedness and sex-investment ratios inLeptothorax tuberum Fabricius

The ant speciesLeptothorax tuberum was shown to be predominantly monogynous. Queens usually mate once only but some nests may have a multiply-mated queen or are partially or serially polygynous. As expected from these results, within nest relatedness between workers and between workers and alate queens was found to be high. Almost fifty percent of nests had no nest queen which may indicate high queen mortality, queens leaving to found new nests or nest fragmentation. Observed female investment frequencies (IF _o ) were not significantly different from those expected on the basis of worker control of sexual production and the relatedness estimates of workers to alate queens and workers to males calculated from isozyme data (IF _E ). These values were not consistent with queen control. There was no evidence for lower IF _o s in queenless nests nor for higher IF _o s in larger nests classified by worker number. When nests were classified by sexual productivity, however, there was a strong rank correlation between productivity and female bias. This is the first study of an ant species to test observed IF against expected IF calculated without inferring between caste relatedness from worker data or pooling of data from different castes.     

基于地形因素的高寒草甸土壤温湿度和物种多样性与初级生产力关系研究

山地是高寒草甸的主要分布区,地形变化引起了土壤温湿度和物种的差异性分布,进而影响到草地生态系统生产功能。为明晰高寒草甸山地环境因子(土壤温湿度)和物种多样性(丰富度、多度、均匀度、优势度)与初级生产力的关系,本研究以青藏高原东北缘马牙雪山支脉的高寒草甸山体为研究对象,选择阶地、阴坡、山脊和阳坡与3个海拔梯度段,调查了189个样方的植物群落组成和土壤温湿度。采用线性回归法分析土壤温湿度和物种多样性与初级生产力之间的关系。结果表明:(1)以山地高寒草甸整体为研究单元,初级生产力只随物种多度的增加而显著增加(R~2=0.07 P=0.01)。(2)坡向影响初级生产力的因素不同,阴坡初级生产力与物种丰富度正线性相关;山脊初级生产力与土壤湿度正线性相关,也随物种丰富度增加而显著增加;阳坡初级生产力与物种多度正线性相关;阶地初级生产力随均匀度增加而显著增加,随优势度增加而显著降低。(3)只有低海拔区(2860-2910 m)初级生产力随物种多度和丰富度的增加而显著增加。综上所述,山地高寒草甸土壤温湿度和物种多样性与初级生产力关系受坡向比海拔的影响更大,且物种多样性对初级生产力的影响大于土壤温湿度。建议山地高寒草甸生态系统生产和生态管理过程中要重点考虑坡向对植物多样性和初级生产力的影响。     

Sucrose medium osmolality as a regulator of anabolic and catabolic parameters in Zymomonas culture

This study focuses on the growth of Zymomonas mobilis strain 113 S and its ethanol and levan production under the conditions of increasing sucrose medium osmolality caused by NaCl, KCl, sorbitol or maltose. The increase in medium osmolality (700–1,500 mosml/kg) was accompanied by the inhibition of growth (growth rate, biomass yield) and ethanol production (specific productivity and yield) In contrast, levan synthesis was less affected or even stimulated and, as a consequence, levan specific productivity was increased significantly. A decrease in the anabolic growth parameters correlated with a parallel inhibition of glucose-6-P dehydrogenase and alcohol dehydrogenase (isoenzyme ADH II) activities. A significant inverse linear relationship (r = ? 0.932, 1 ? P = 0.01) was observed between the values of the specific productivities of ethanol and levan. This relationship was confirmed independently by a controlled reduction of growth and ethanol productivity (3.75–4.75 mM sodiumbisulphite as an acceptor of acetaldehyde formed in the pyruvate decarboxylase reaction). As further support of this relationship, a significant inverse correlation was observed between levan specific productivity and ATP concentration in Zymomonas mobilis cells, most probably demonstrating that a reduced level of energetic metabolism is favourable for levan production.     

JobCenter: an open source, cross-platform, and distributed job queue management system optimized for scalability and versatility

ABSTRACT: BACKGROUND: Laboratories engaged in computational biology or bioinformatics frequently need to run lengthy, multistep, and user-driven computational jobs. Each job can tie up a computer for a few minutes to several days, and many laboratories lack the expertise or resources to build and maintain a dedicated computer cluster. RESULTS: JobCenter is a client-server application and framework for job management and distributed job execution. The client and server components are both written in Java and are cross-platform and relatively easy to install. All communication with the server is client-driven, which allows worker nodes to run anywhere (even behind external firewalls) and provides inherent load balancing. Adding a worker node to the worker pool is as simple as dropping the JobCenter client files onto any computer and performing basic configuration, providing tremendous ease-of-use, flexibility, and limitless horizontal scalability. Each worker installation may be independently configured, including the types of jobs it is able to run. Executed jobs may be written in any language and may include multiple execution steps. CONCLUSIONS: JobCenter is a versatile and scalable distributed job management system that allows laboratories to very efficiently distribute all computational work among all available resources. JobCenter is freely available at http://code.google.com/p/jobcenter/.     

浙江定海次生林内物种丰富度与生物量和生产力关系的环境依赖性

迄今生物多样性与生态系统功能关系的研究主要在物种组成随机配置的人工生态系统中进行, 在自然生态系统中研究较少, 且未考虑环境因子如何影响生态系统功能及其与生物多样性的关系。本研究选取亚热带广泛分布的次生林为研究对象, 利用模型拟合的方法, 探讨亚热带次生林中物种丰富度与生物量和生产力之间的关系, 以及环境因子(海拔、坡度、坡向、土层厚度)和次生林恢复时间(林龄)对生物量、生产力、物种丰富度与生物量和生产力间关系的影响。结果表明, 当不考虑环境因子时, 物种丰富度与生物量之间存在显著的线性正相关关系, 而与生产力之间存在显著的二次关系(先增加后减少的驼峰型)。当考虑环境因子时, 个体密度和土层厚度对生物量具有显著影响, 而环境因子对生产力并无显著效应。在坡度较陡、坡向朝南及土层较厚的环境条件下, 物种丰富度与生物量具有显著的线性正相关关系; 而在坡度较缓、坡向朝北及土层较薄的环境条件下, 物种丰富度不影响生物量。在较高海拔环境条件下, 生产力随物种丰富度先增加后减少(驼峰形状), 而在其他环境条件下, 生产力均不响应物种丰富度。以上结果说明自然森林生态系统中物种丰富度与生物量和生产力的关系存在差异, 且其相互间的关系依赖于环境因子。     

Performance of Myrmica ant colonies is correlated with the presence of social parasites

1. The performance of ant colonies depends on different factors such as nest site, colony structure or the presence of pathogens and social parasites. Myrmica ants host various types of social parasites, including the larvae of Maculinea butterflies and Microdonmyrmicae (Schönrogge) hoverfly. How these social parasites affect host colony performance is still unexplored. 2. It was examined how the presence of Maculinea teleius Bergsträsser, Maculinea alcon (Denis & Schiffermüller), and M. myrmicae larvae, representing different feeding and growth strategies inside host colonies, is associated with worker survival, the number of foragers, and colony productivity parameters such as growth and reproduction. 3. It was found that the presence of social parasites is negatively associated with total colony production and the production of ant larvae and gynes. Male production was lower only in nests infested by M. teleius, whereas the number of worker pupae was significantly higher in all types of infested colonies than in uninfested colonies. Laboratory observations indicated that nests infested by Maculinea larvae are characterised by a higher number of foragers compared to uninfested nests but we did not find differences in worker survival among nest types. 4. The observed pattern of social parasite influence on colony productivity can be explained by the feeding strategies of parasitic larvae. The most negative effect was found for M. teleius, which feeds on the largest host brood and eliminates a high number of sexual forms. The strong, adverse influence of all studied parasite species on gyne production may result in low queen production in Myrmica populations exposed to these social parasites.     

An optical-density-based feedback feeding method for ammonium concentration control in Spirulina platensis cultivation

Cultivation of Spirulina platensis using ammonium salts or wastewater containing ammonium as alternative nitrogen sources is considered as a commercial way to reduce the production cost. In this research, by analyzing the relationship between biomass production and ammonium- N consumption in the fed-batch culture of Spirulina platensis using ammonium bicarbonate as a nitrogen nutrient source, an online adaptive control strategy based on optical density (OD) measurements for controlling ammonium feeding was presented. The ammonium concentration was successfully controlled between the cell growth inhibitory and limiting concentrations using this OD-based feedback feeding method. As a result, the maximum biomass concentration (2.98 g/l), productivity (0.237 g/l·d), nitrogen-to-cell conversion factor (7.32 gX/gN), and contents of protein (64.1%) and chlorophyll (13.4 mg/g) obtained by using the OD-based feedback feeding method were higher than those using the constant and variable feeding methods. The OD-based feedback feeding method could be recognized as an applicable way to control ammonium feeding and a benefit for Spirulina platensis cultivations.     

The Misuse of Chayanov: "Chayanov's Rule" and Empiricist Bias in Anthropology

Sahlins's "Chayanov's Rule"–the more consumers each worker has to support the more work each worker does-has characterized Chayanov's analysis for most anthropologists. I examine the relationship between the consumer/worker ratio and product per worker for the Shan community of Thongmakhsan in northwestern Thailand. Since there is no systematic relationship between these variables even when the population is divided into production strategy groups, I go on to examine the relationship between Sahlins's "Chayanov's Rule" and Chayanov's own analysis. In conclusion I raise the issue of the continuing identification of Chayanov with "Chayanov's Rule" and consider a number of possible reasons for this.     

Advantages and disadvantages of large colony size in a halictid bee: the queen's perspective

The size of the group of social species might influence basicaspects of productivity and social interactions. In many primitivelysocial insects, foundress queens are basically in control ofthe number of workers in their first brood. We examined factorsthat might influence the optimal number of workers a queen shouldproduce during the solitary founding phase in Lasioglossum malachurum(Hymenoptera, Halictidae). A priori, it seems plausible thatshe should produce as many workers as possible (1) to maximizecolony productivity and (2) to minimize the impact of broodparasitoids. However, there might also be unfavorable consequencesof a large colony size from the queen's perspective. First,the queen might incur disproportionately high costs that decreaseher potential for subsequent reproduction. Second, the queenmight not be able to suppress the development of ovaries ina large number of workers. As a clear advantage of a large colonysize, we found an increased production of sexuals. Contraryto our expectation, in the first worker phase, nests that wereparasitized by Sphecodes bees had more workers than did unparasitizednests. We found no evidence that the production of the firstworker brood entailed costs to the queen. However, the degreeof development of worker ovaries increased with colony size,and some degree of development was detectable with as few asfour workers. This study shows that the number of workers aqueen produces might depend on the interaction of several factors,some of which have not been considered in detail yet.     

Plankton photosynthesis, extracellular release and bacterial utilization of released dissolved organic carbon (RDOC) in lakes of different trophy

The major objective of these studies was to assess the extent of the flow of released dissolved organic carbon (RDOC) from phytoplankton to heterotrophic bacteria. The second aim was to test Nalewajko and Schindler's (1976) hypothesis that the percentage of extracellular release (PER) of RDOC by phytoplankton is higher in oligotrophic than eutrophic waters. The studies on the relationship between the bacterial assimilation of RDOC and productivity of phytoplankton in the lakes of different trophy have shown a direct correlation. It was observed that higher utilization rate of phytoplankton RDOC occurred in lakes with higher primary production. The inverse relationship between productivity of lakes, i.e. trophy of waters, and amount of RDOC or PER is closely dependent on the heterotrophic activity of bacteria in waters.     

Queen recruitment and split sex ratios in polygynous colonies of the ant Formica exsecta

Sex ratios in social insects have become a general model for tests of inclusive fitness theory, sex ratio theory and parent–offspring conflict. In populations of Formica exsecta with multiple queens per colony , sex ratios vary greatly among colonies and the dry-weight sex ratio is extremely male-biased, with 89% of the colonies producing males but no gynes (reproductive females). Here we test the queen-replenishment hypothesis, which was proposed to explain sex ratio specialization in this and other highly polygynous ants (i.e. those with many queens per nest). This hypothesis proposes that, in such ants, colonies produce gynes to recruit them back into the colony when the number of resident queens falls below a given threshold limiting colony productivity or survival. We tested predictions of the queen-replenishment hypothesis by following F. exsecta colonies across two breeding seasons and relating the change in effective queen number with changes in sex ratio, colony size and brood production. As predicted by the queen-replenishment hypothesis, we found that colonies that specialized in producing females increased their effective queen number and were significantly more likely to specialize in male production the following year. The switch to male production also coincided with a drop in productivity per queen as predicted. However, adoption of new queens did not result in a significant increase in total colony productivity the following year. We suggest that this is because queen production comes at the expense of worker production and thus queen production leads to resource limitation the following year, buffering the effect of greater queen number on total productivity.