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71.
72.
Why do workers decide to go on strike or change their mind during a strike? This field study aims to determine to what extent employees' perceptions of justice formed during the collective bargaining process influence their strike vote. Data were collected from a North American university faculty that went on strike 21 months after the expiration of its collective agreement. The results show that perceived justice about collective bargaining is a determinant of the strike vote. The role played by the employer and the union as a source of (in)justice and the importance of the four types of justice perceptions (procedural, distributive, interpersonal, and informational) vary depending on the context of ballots (initiate, continue, or end the strike). This suggests that the reduction of uncertainty leads to the activation of three different mechanisms: judgmental heuristics (salience), social comparison, and cognitive dissonance. The results also suggest that employees attempt to be as rational as possible when they decide to go on strike. Nevertheless, the decision to join strikers and to continue the strike is partly based on an emotional process: employees use the strike to punish the employer. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
73.
Natalie M. Sopinka Julie R. Marentette Sigal Balshine 《Behavioral ecology and sociobiology》2010,64(12):1947-1958
There is increasing concern for the disruptive effects seen in aquatic species exposed to environmental contaminants. However,
few studies have investigated the impact of such contaminants on the behavior of individuals living in exposed waters. Contaminant
exposure can affect animal populations by disrupting behaviors including feeding, locomotion, and mating. In this study, we
examined how living in an ecosystem polluted by combinations of polycyclic aromatic hydrocarbons, polychlorinated biphenyls,
and heavy metals (arsenic, cadmium, iron, lead, zinc) impacts contest behavior in the round goby (Neogobius melanostomus). Fish collected from heavily contaminated and cleaner sites in Lake Ontario were subjected to a resource contest to determine
the effect of these contaminants on aggression and the establishment of dominance hierarchies, which in turn influence access
to food, shelter, and mating opportunities. Dominance establishment (a clear resource winner) was less obvious among fish
from the contaminated site compared to the more stable hierarchies that formed between pairs of fish from the clean site.
Pairs of fish from the contaminated site performed more assessment displays compared to fish from clean sites. These results
suggest that the costs of living in an environment under exposure can shape behavioral repertoires. The altered conflict resolution
strategies of contaminated fish may reflect impaired cognitive function, sensory perception, and/or higher metabolic load
associated with aggression. This study provides support for the utilization of quantifiable behavioral differences as ecologically
relevant measures of contaminant exposure. 相似文献
74.
David J. Grand Thomas K. Egglin William W. Mayo-Smith John J. Cronan Julie Gilchrist 《Journal of Safety Research》2012,43(5-6):413-415
Foreign object ingestion is a common reason for visiting an emergency department; however, wire grill-cleaning brush bristles are an uncommon foreign object. This report describes a series of twelve cases identified in a single hospital system from July 2009 through June 2012. Patients included six males and six females; ages ranged from 11 to 75 (mean: 47 years). The patients all reported recent outdoor residential food grilling and use of commercially available wire grill-cleaning brushes. The severity of injury ranged from puncture of the soft tissues of the neck, causing severe pain on swallowing, to perforation of the gastrointestinal tract requiring emergent surgery. Before cooking, persons should examine the grill surface carefully for the presence of wire bristles that might have dislodged from the grill brush and could embed in cooked food. Alternative residential grill-cleaning methods or products might be considered. 相似文献
75.
A series of field surveys were carried out on two permanent pools of the upper Glenelg River in SW Victoria, Australia. One was representative of the wider and deeper pools while the other was representative of the more-narrow and shallower pools. Both pools showed a typical seasonal cycle of warm, brackish, oxygen-poor, summer conditions and cool, oxygen-rich, low-salinity, winter conditions. The summer salinity increases were larger than expected, suggesting possible saline groundwater inflow from unidentified springs. Both pools contained anoxic water in their deeper sections but this was permanent only in the deeper pool. A simple model of the flushing rate of such anoxic pools subject to flows, such as environmental flow releases, was developed, based on an energy balance between the potential energy required to lift the anoxic layer and the kinetic energy derived from the river flow. The results were tested against and in agreement with the field measurements. The model also suggests that the anoxic layers are resilient to all but the largest environmental flows. 相似文献
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78.
Landscape Assessment of the Degree of Protection of Alaska's Terrestrial Biodiversity 总被引:1,自引:0,他引:1
David Cameron Duffy § Keith Boggs Randall H. Hagenstein ‡ Robert Lipkin and Julie A. Michaelson 《Conservation biology》1999,13(6):1332-1343
Abstract: We assessed the degree to which Alaskan lands reflect the state's biodiversity by dividing the entire state into four categories of land protection ranging from highly protected to minimally protected in terms of potential for future development. We then compared the percentage of each ecoregion and plant-cover type in each land protection class. We assumed that 12% protection represents an acceptable minimum and examined the percentage of site records of rare plants in protected and unprotected areas. Of 28 ecoregions in Alaska, 15 (63.4%) have <12% of their area in highly protected areas. Similarly, 11 of 21 vegetation-cover types (43.7%) have <12% protection. For 32 rare vascular plants, an average of 27% of records occur on highly protected lands. Seventy-five percent of the rare plants had <50% of their records from highly protected lands. Less than 1% of Alaska has been permanently altered by human activity. In contrast to the lower 48 states, time remains to plan development that preserves biodiversity while permitting an economically sustainable economy—if the effort is made now. 相似文献
79.
80.
The sabellid polychaete Sabellastarte spectabilis (Grube 1878) was collected at approximately monthly intervals from January 2002 to December 2003 from intertidal and subtidal
reefs near the Hawaii Institute of Marine Biology in Kane’ohe Bay, Hawaii, USA (21°N, 157°W). Gametogenesis and spawning periodicity
were investigated using histological techniques and induction of spawning trials. Worms were characterized into four discrete
reproductive stages based on histological evidence: (1) No evidence of reproductive activity in the coelom (sex cannot be
determined), (2) Only coelomocytes present in the coelom (sex cannot be determined), (3) Some gametes present in the coelom
(sex can be determined) and (4) Coelom densely packed with gametes (sex can be determined). The small hermaphroditic portion
of the population was not used in this study. Stage 4 worms were present over an extended period of time (females, March–December
and males, March–November) indicating a potentially broad reproductive season. No correlation between day length and maturation
stages in S. spectabilis was detected. However, the statistical model Y = ([394.26 × X] − [7.793 × X
2]) − 4960.781 where Y the % frequency of Stage 4 worms and X the mean monthly water temperature explained 44% of the variation between water temperature and % frequency of Stage 4 worms.
Maturation appeared to coincide with water temperatures of 24–25°C (March–September) after which there is a reduction in the
% frequency of stage 4 individuals. Induction of spawning trials conducted between May and January showed the month of October
with a significantly higher percent success than any other month investigated. According to all available information (e.g.,
natural spawning in water tables, histological data, induction of spawning trials, correlation of maturation stages with observed
changes in average monthly water temperature.), there is an apparent peak in reproductive activity (spawning) within a broad
maturational season, which may be influenced by water temperature. 相似文献