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811.
The current study was designed to replicate findings from previous research regarding the relationships between job stressors, negative affectivity, and counterproductive work behavior (CWB) using peer‐reported data and to assess the effects of workplace incivility on employee satisfaction and CWB. Results indicate that incivility, organizational constraints, and interpersonal conflict were negatively related to job satisfaction and positively related to CWB. Support was also found for the role of negative affectivity as a moderator of the relationship between job stressors and CWB, although only one significant moderator was found using peer‐reported CWB. In general, the relationships between job stressors and CWB were stronger for individuals high in negative affectivity than for individuals low in negative affectivity. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
812.
813.
Mark A. Snyder Lisa C. Sloan Jason L. Bell 《Journal of the American Water Resources Association》2004,40(3):591-601
ABSTRACT: Using a regional climate model (RegCM2.5), the potential impacts on the climate of California of increasing atmospheric CO2 concentrations were explored from the perspective of the state's 10 hydrologic regions. Relative to preindustrial CO2 conditions (280 ppm), doubled preindustrial CO2 conditions (560 ppm) produced increased temperatures of up to 4°C on an annual average basis and of up to 5°C on a monthly basis. Temperature increases were greatest in the central and northern regions. On a monthly basis, the temperature response was greatest in February, March, and May for nearly all regions. Snow accumulation was significantly decreased in all months and regions, with the greatest reduction occurring in the Sacramento River region. Precipitation results indicate drier winters for all regions, with a large reduction in precipitation from December to April and a smaller decrease from May to November. The result is a wet season that is slightly reduced in length. Findings suggest that the total amount of water in the state will decrease, water needs will increase, and the timing of water availability will be greatly perturbed. 相似文献
814.
Terrill R. Hanson Luther Upton Hatch Howard C. Clonts 《Journal of the American Water Resources Association》2002,38(4):1007-1018
ABSTRACT: Wise interbasin management of Southeastern U.S. water resources is important for future development. Alabama‐Coosa‐Tallapoosa and Apalachicola‐Flint‐Chattahoochee River basins' water usage has evolved from power generation to multiple uses. Recreation and housing have become increasingly valuable components. Changing use patterns imply changing resource values. This study focused on six Alabama reservoirs, using contingent valuation questions in on‐site, telephone, and mail surveys to estimate impacts on lakefront property values, recreational expenditures, and preservation values for scenarios of permanent changes to reservoir water quantity. As summer full‐pool duration decreased, lakefront property value decreased, and as duration increased, property values increased, but at a lesser rate. Similar findings occurred for winter draw down alternatives. Permanent one‐foot reductions in summer full‐pool water levels resulted in a 4 to 15 percent decrease in lakefront property values. Recreational expenditures decreased 4 to 30 percent for each one‐foot lowering of reservoir water levels. Current nonusers of the six reservoirs showed strong preferences for protecting study reservoirs with willingness to pay values of 47 per household or approximately 29 million for the entire six‐reservoir watershed basin area. Resource management based on historic use patterns may be inappropriate and more frequent and comprehensive valuation of reservoir resources is needed. 相似文献
815.
Ann Curtis Lisa Strain Moira Mennie Susan Holloway J. A. Raeburn G. T. N. Besley D. J. H. Brock 《黑龙江环境通报》1988,8(8):625-628
First-trimester prenatal diagnosis of cystic fibrosis (CF) using linked DNA markers is usually only possible if there is an index affected child to establish the haplotype of the parental chromosomes. We describe a prenatal diagnosis where fibroblasts, cultured from the skin of a deceased affected child and then held in frozen storage for 3 years, were used as the starting point for tracking the CF gene. The fetus was diagnosed as a homozygous normal and the diagnosis confirmed by immunoreactive trypsin testing after birth. It was also possible to establish heterozygosity in the aunt of the affected child. 相似文献
816.
817.
Paolo Lo Bue Stefano Colazza Lisa D. Forster Jocelyn G. Millar Robert F. Luck 《Chemoecology》2004,14(3-4):151-156
Summary. Metaphycus sp. nr.
flavus (Encyrtidae: Hymenoptera)
is a parasitoid species collected from the Mediterranean
region which lays its eggs in the immature stages of several
economically important soft scale insects (Hemiptera:
Coccidae), including brown soft scale, Coccus hesperidum
L. (= host insect). Preliminary tests suggested that the parasitoid
is most successful in producing offspring when it
oviposits in the younger stages of brown soft scale. In
Y-olfactometer bioassays measuring wasp choices and residence
times, naïve parasitoids were significantly more
attracted to yucca leaves infested with 26, 27, or 28 d-old
scale than to uninfested leaves, whereas leaves with older
(29-30 d-old) scale were no more attractive than uninfested
leaves. Parasitoids also spent significantly more time in the
arm with yucca leaves infested with 26 d-old scale than in
the arm with uninfested leaves. These results are consistent
with observations of the parasitoids reproductive success on
scale of different ages, whereby older scale are more likely
to encapsulate the developing eggs of M.
sp. nr. flavusfemales than are younger scale. Further bioassays determined
that yucca leaves that had been infested with 26 d-old
scale but from which the scale had been removed were as
attractive as infested leaves. In contrast, infested yucca
leaves from which scale had been removed and the leaves
subsequently washed with distilled water were less attractive
than infested leaves. Furthermore, the wash water
containing scale residues was attractive to female wasps. In
total, these results suggest that Metaphycussp. nr. flavus
females utilize volatile, water soluble compounds produced
by brown soft scale as cues to locate suitable hosts. 相似文献
818.
Mating success on white-bearded manakin (Manacus manacus) leks: male characteristics and relatedness
Lisa Shorey 《Behavioral ecology and sociobiology》2002,52(6):451-457
Morphological, territorial, and behavioural characteristics were measured on white-bearded manakin (Manacus manacus) males from two leks in two consecutive years. These data were combined with data on marker-inferred relatedness to study possible co-variation with mating success. In one year, male size and male condition were correlated with mating success. In both years, males holding courts nearer the lek centre gained more matings. No observed male display behaviour appeared to be an independently important factor in explaining variance in male mating success. Successful males made more aggressive displays than non-successful males and more displays were between close relatives. Number of aggressive displays increased as the distance between male courts decreased. Mating success in the white-bearded manakin is most likely mediated by a combination of morphological and behavioural characteristics, influencing both male-male competition and female choice. Females could potentially use centrality on the lek as an indicator of male characteristics. However, levels of relatedness may influence spatial arrangement of males on a lek thereby affecting male-male interactions and ultimately influencing patterns of mating success. 相似文献
819.
Avian Species Richness in Different-Aged Stands of Riparian Forest Along the Middle Rio Grande, New Mexico 总被引:3,自引:0,他引:3
Greg H. Farley Lisa M. Ellis James N. Stuart Norman J. Scott Jr. 《Conservation biology》1994,8(4):1098-1108
Riparian forests are important for maintaining vertebrate species richness in the southwestern United States, but they have become restricted in distribution due to both historical and current management practices. In order to counteract continued loss of this habitat, several mitigation programs were developed in the middle Rio Grande Valley of New Mexico. Three areas ranging from 50 to 140 ha were revegetated with native trees using pole planting and cattle exclosures, and changes in vegetation structure were quantified after 2, 3, and 5 years of growth. As expected, the older site contained the most heterogeneous mix of plant species and the greatest structural diversity. We compared year-round avian use of the revegetated sites with a mature cottonwood forest site of approximately 30 years of age. As the revegetated sites matured and salient habitat features changed, the population dynamics of individual avian species and patterns of guild structure varied. The older revegetated sites showed a greater similarity to the mature cottonwood site, suggesting that reclamation efforts established quality riparian habitats for birds in as little as 5 years. The revegetated sites appeared especially important for Neotropical-migrant birds. We suggest that a mosaic of riparian woodlands containing mixtures of native tree and shrub species of different size classes is necessary to maintain avian species richness in the middle Rio Grande drainage, and probably throughout the southwestern United States. 相似文献
820.
Allison C. Alberts Jeffrey M. Lemm Andrew M. Perry Lisa A. Morici John A. Phillips 《Behavioral ecology and sociobiology》2002,51(4):324-335
In small, insular populations, behavioral patterns that lead to increased variance in individual reproductive success can
accelerate loss of genetic variation. Over a 1-year period, we documented behavior and hormone levels in a breeding group
of adult Cuban iguanas (Cyclura
nubila) at Guantánamo Bay. Male dominance was associated with body and head size, display behavior, testosterone levels, home-range
size, and proximity to females. Based on their success in agonistic encounters, we ranked males in a linear dominance hierarchy.
During the subsequent breeding season, we conducted a removal experiment in which the five highest-ranking males were temporarily
relocated from the study site. Although we were unable to assess reproductive success directly, previously lower-ranking males
assumed control of vacated territories, won more fights, and increased their proximity to females in the absence of the dominant
males. When it results in greater mating opportunities for otherwise socially suppressed individuals, temporary alteration
of local social structure may help limit erosion of genetic variation in small, insular populations.
Electronic Publication 相似文献