同事关系质量及其作用机制

Although the research into coworker relationship quality has been recognized one of key factors related to organization performance, and has been thought a new trend in organization behavior research with the flatting of organization structure and complication of task assignment, there is relatively little empirical research on the mechanism between coworkers’ interaction, contraring to the fruitful results on member exchange research based on social network theory, say nothing of the influence of cultural differences such as GUANXI. This research developed the scale for the assessment of Coworker Relationship Quality by literature review, deep interview, and questionnaires, compared the predictable ability of Coworker Relationship Quality (CRQ) scale and Coworker Exchange (CWX) scale on employees’ work attitudes and behaviors. Finally, the mediating effect of Coworker Relationship Quality between employees’ similarities on personality and their work attitudes and behaviors was investigated. Following are main results. Firstly, we found that the interpersonal communication, trust, and mutual support are the key factors of coworker relationship quality, which is similar to the result getting from western samples. But Chinese people are more GUANXI ORIENTATION, means they want to build longtime relationship with others, not only when they are coworkers, but also when one of them left the organization. Secondly, though the core meaning of CRQ and CWX are same, their predictable ability on organization outcomes is different. CRQ is more powerful than CWX, especially on turnover intention. The result showed that after controlling the effect of demographic variables and CRQ, CWX cannot predict turnover intention significantly, but CRQ can still predict turnover intention significantly after controlling demographic variables and CWX. Thirdly, the partial mediating effect of CRQ between positive affectivity similarity and organizational citizenship behavior, coworker satisfaction, organizational commitment and turnover intention are validated, but we did not find the mediating effect of CRQ between demographic variable similarity and workers’ attitudes and behaviors. The Similarity Attraction Paradigm, Social Identity Theory, and Self Category Theory were supported.

成年女儿照料老年父母的心理体验及关系质量作用的研究

Previous researches about family caregiving revealed that caregiving has both negative and positive effects on caregivers’ well-being. Based on Lawton’s two-factor model, this study aims at examining how caring for old parents would affect adult daughters’ psychological well-being. According to Lawton, objective stressors as caregiving would arouse two different kinds of caregivers’ subjective appraisal, i.e., negative appraisal and positive appraisal, which in turn correlate with the negative and positive dimensions of caregivers’ psychological well-being, respectively. There were two main purposes of this study: a) to verify both the negative and positive paths in the two-factor model and their relatively independence; and b) to examine the effects of relationship quality between caregiver and care-recipient on those paths. The results are as follows: 1) Caregiving stressors have significant positive predictive effect on caregivers’ negative appraisal, but have no direct effect on caregivers’ positive appraisal. 2) Caregivers’ negative appraisal has significant positive predictive effect on their negative emotional experience, while caregivers’ positive appraisal has significant positive predictive effect on their positive emotional experience. 3) Certain dimensions of relationship quality, including the Appreciation and General Appraisal, have significant negative predictive effect on caregivers’ negative appraisal, and have significant positive predictive effect on caregivers’ positive appraisal. 4) The Appreciation dimension of relationship quality moderates the path from caregiving demands to caregivers’ burden; and the General Appraisal of relationship quality moderates the path from caregivers’ positive appraisal to life satisfaction. Based on the above results, the researcher concluded that a) both the negative path and positive path exist in caregiving process, and they are relatively independent from each other; and b) relationship quality does moderate certain paths in the model. Meanwhile, the main effect of relationship quality on caregivers’ experience is also significant and more remarkable. This study attempts to explain these results in terms of coping resources. Both relationship quality and many other factors might be explained as resources that caregivers utilize to cope with stress of caregiving. With more resources, caregivers tend to appraise more positively, and less negatively, and vice versa. However, the resources which might affect caregivers’ positive appraisal, as well as the ways they work, may be different from that affect caregivers’ negative appraisal.

Structure of the phytoplankton community and its relationship to water quality in Donghu Lake, Wuhan, China

The phytoplankton community structure, in terms of species composition, total standing crop, and abundance of the dominant algal species, at four stations in Donghu Lake, Wuhan, China, was investigated monthly from January 1994 to December 1996. A total of 260 taxa was observed, of which Chlorophyta (106 taxa) contributed the highest portion of the total number of taxa, followed by Bacillariophyta (82 taxa) and Cyanophyta (32 taxa). The total standing crop measured by means of chlorophyll a content, cell density, and cell biovolume, as well as the abundance of the dominant species, declined in the order of Station I to Station IV. Seasonal changes of the standing crop varied greatly among the four stations. Although the cell density at the four stations showed a single peak within a year, the peak density varied from July to November, dependent on the sampling year and the station. For chlorophyll a content and cell biovolume, multiple peaks were observed at Stations I and II, but a single peak was found at Stations III and IV. The phytoplankton community structure indicated that the trophic status was the highest at Station I (most eutrophic), followed by Station II; Stations III and IV were the least trophic areas. The long-term changes in phytoplankton community structure further suggested that changes in phytoplankton community structure were correlated with water quality, and eutrophication of Donghu Lake had been aggravated since the 1950s.

PCR-DGGE Fingerprinting Analysis of Plankton Communities and Its Relationship to Lake Trophic Status

Plankton communities in eight lakes of different trophic status near Yangtze, China were characterized by using denatured gradient gel electrophoresis (DGGE). Various water quality parameters were also measured at each collection site. Following extraction of DNA from plankton communities, 16S rRNA and 18S rRNA genes were amplified with specific primers for prokaryotes and eukaryotes, respectively; DNA profiles were developed by DGGE. The plankton community of each lake had its own distinct DNA profile. The total number of bands identified at 34 sampling stations ranged from 37 to 111. Both prokaryotes and eukaryotes displayed complex fingerprints composed of a large number of bands: 16 to 59 bands were obtained with the prokaryotic primer set; 21 to 52 bands for the eukaryotic primer set. The DGGE-patterns were analyzed in relation to water quality parameters by canonical correspondence analysis (CCA). Temperature, pH, alkalinity, and the concentration of COD, TP and TN were strongly correlated with the DGGE patterns. The parameters that demonstrated a strong correlation to the DGGE fingerprints of the plankton community differed among lakes, suggesting that differences in the DGGE fingerprints were due mainly to lake trophic status. Results of the present study suggest that PCR-DGGE fingerprinting is an effective and precise method of identifying changes to plankton community composition, and therefore could be a useful ecological tool for monitoring the response of aquatic ecosystems to environmental perturbations.

The co-evolutionary relationship between bitterling fishes and freshwater mussels: insights from interspecific comparisons

Hypothesis: In parasites that use hosts for offspring development, adults may base oviposition decisions on a range of host traits related either to host quality or the co-evolutionary relationship between parasite and host. We examined whether host quality or co-evolutionary dynamics drive the use of hosts in the bitterling-mussel relationship. Organisms: Six species of bitterling fish (Acheilognathinae) and eight species of freshwater mussels (Unionidae, Corbiculidae) that are used by bitterling for oviposition. Site of experiments: Experimental tanks in Wuhan, China, at the site of the natural distribution of the studied species. Methods: Three experiments that controlled for host accessibility and interspecific interactions were conducted to identify host preferences among bitterling fishes and their mussel hosts. We started with a broad interspecific comparison. We then tested bitterling behavioural choices, their temporal stability, and mussel host ejection behaviour of the eggs of generalist and specialist bitterling species. Finally, we measured host mussel quality based on respiration rate and used published studies on mussel gill structure to infer mussel suitability as hosts for bitterling eggs. Results: We found significant interspecific differences among bitterling species in their use of mussel hosts. Bitterling species varied in their level of host specificity and identity of preferred hosts. Host preferences were flexible even among apparently specialized species and fishes switched their preferences adaptively when the quality of individuals of preferred host species declined. Mussels varied considerably in their response to oviposition through egg ejections. Host preference by a generalist bitterling species correlated positively with host quality measured as the efficiency of the mussel gills to extract oxygen from inhaled water. Host ability to eject bitterling eggs correlated positively with their relative respiration rate, probably due to a higher velocity of water circulating in the mussel gill chamber.

Development of the microbial communities in Lake Donghu in relation to water quality

There is increasing recognition that protozoa is very useful in monitoring and evaluating water ecological healthy and quality. In order to study the relationship between structure and function of protozoan communities and water qualities, six sampling stations were set on Lake Donghu, a hypereutrophic subtropical Chinese lake. Microbial communities and protists sampling from the six stations was conducted by PFU (Polyurethane foam unit) method. Species number (S), diversity index (DI), percentage of phytomastigophra, community pollution value (CPV), community similarity and heterophy index (HI) were mensurated. The measured indicators of water quality included total phosphorus (TP), dissolved oxygen (DO), Chemical oxygen demand (COD), NH4 (+), NO2 (-) and NO3-. Every month water samples from stations I, II, III, IV were chemically analyzed for a whole year, Among the chemically analyzed stations, station I was the most heavily polluted, station II was the next, stations III and IV had similar pollution degrees. The variable tendencies of COD, TP, NH3, NO2-, NO3-, and DO during the year was approximately coincident among the six stations. Analysis from the community parameters showed that the pollution of station 0 was much more serious than others, and station V was the most slight. Of the community parameters, CPV and HI were sensitive in reflecting the variables of the water quality. Community similarity index was also sensitive in dividing water qualities and the water quality status of different stations could be correctly classified by the cluster analysis. DI could reflect the tendency of water quality gradient, species number and percentage of Phytomastigophora was not obvious in indicating the water quality gradient.

Development of a biotic index using the correlation of protozoan communities with chemical water quality

A method of comparing data on protozoan communities with chemical parameters is presented. Using data from an extensive survey of the River Hanjiang in China, each species of protozoa has been given a species pollution value (SPV) related to its occurrence in waters with different degrees of pollution. A comprehensive chemical index is calculated for each site based on water quality standards for eight chemical parameters. The index is calculated from the relationship between the observed levels of each chemical at a site, compared with the limits of the drinking water quality standards of the People's Republic of China. From the distribution of each species at sites with differing chemical index values, a SPV is calculated. The SPV for each species is obtained by summing the logarithmic value of 10 times the chemical pollution divided by the number of chemical parameters, then divided by the stations where the species occurs. The community pollution value (CPV), which is the average SPVs of all protozoa at a site, is used to evaluate water quality. The CPV has been shown to have a close correlation with the degree of water pollution. It is not necessary for all the protozoa in a sample to have SPVs listed in this paper, provided at least 56% of the protozoa in a sample have an SPV value, the CPV will be applicable.

Use of computer-assisted sperm analysis (CASA) to evaluate the quality of cryopreserved sperm in red seabream (Pagrus major)

In the present study, the quality of post-thaw sperm of red seabream Pagrus major frozen with 6-24% DMSO was investigated. The motility, average path velocity and fertilizing capacity of fresh and their corresponding post-thaw sperm were examined for evaluation of the post-thaw sperm motion characteristics and its association with fertilizing capacity. An analysis of sperm motility before and after cryopreservation has been performed using computer-assisted sperm analysis (CASA). For post-thaw sperm frozen with 12-21% DMSO, the percentages of motile sperm were not significantly (P > 0.05) changed 10 s after activation. Moreover, the main motility pattern and swimming velocity of the motile post-thaw sperm were not significantly (P > 0.05) changed and the progressive linear motion was still the dominant pattern. However, the total motility of post-thaw sperm (72.3 +/- 6.3%) 30 s after activation was (P < 0.05) lower than the corresponding fresh sperm (82.7 +/- 7.2%). Additionally, the fertilizing capacity of post-thaw sperm was investigated with a standardized sperm to egg ratio 500:1. There is a linear regression relationship between the percentage of motile post-thaw sperm and fertilizing capability. These data demonstrate that 12-21% DMSO can provide good protection to the sperm during the freezing-thawing process. (c) 2006 Elsevier B.V. All rights reserved.