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671.
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
672.
Karsten Klint Jensen Jan Tind Sørensen 《Journal of Agricultural and Environmental Ethics》1998,11(2):85-100
This paper presents the idea of a decision-support system for a livestock farm, called “ethical accounting”, to be used as
an extension of traditional cost accounting. “Ethical accounting” seeks to make available to the farmer information about
how his decisions affect the interests of farm animals, consumers and future generations. Furthermore, “ethical accounting”
involves value-based planning. Thus, the farmer should base his choice of production plan on reflections as to his fundamental
objectives, and he should make his final decision only after having seriously considered the various consequences for the
affected parties.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
673.
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
674.
Steen Smidt-Jensen M.D. Niels Hahnemann Jalil Hariri Peter K. A. Jensen Aage J. Therkelsen 《黑龙江环境通报》1986,6(2):125-132
A consecutive series of 26 women followed to term after first trimester transabdominal chorionic villi sampling is presented. The clinical application of transabdominal chorionic villi sampling (TA-CVS) seems to have certain advantages, especially from the patients' point of view, but also in regard to successful sampling and to the complication ratio. The results in this clinical trial revealed no cases of abortions, no signs of placental damage and no cases of vaginal bleeding or infections. 相似文献
675.
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
676.
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
677.
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
678.
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
679.
Carrie Jones Carol Booth Debra Rita Lydia Jazmines Rhonda Spiro Brian McCulloch Christopher McCaskill Lisa G. Shaffer 《黑龙江环境通报》1995,15(9):843-848
We report a case of maternal uniparental disomy of chromosome 10 discovered after chorionic villus sampling (CVS). Direct preparations revealed mosaic trisomy 10, while cultured CVS cells, as well as amniotic fluid cells, showed only a normal 46,XY complement. DNA analysis using microsatellite markers showed both chromosomes 10 to have been inherited from the mother. The pregnancy was complicated by polyhydramnios. A phenotypically normal male infant of appropriate size was delivered by Caesarean section at 41 weeks' gestation. Since only the direct preparations showed trisomy 10, this case illustrates the importance of CVS direct preparations in the detection of pregnancies at risk of uniparental disomy (UPD). Although the increased frequency of confined placental mosaicism (CPM) diagnosed when direct preparations are performed has been viewed negatively, identification of both CPM and UPD may have biological and clinical significance for a pregnancy. Even though only a single case of maternal disomy 10 is reported here, the apparently normal phenotype provides evidence that there are no major imprinted loci on chromosome 10 that affect in utero growth and development. However, other potential effects such as mental retardation will require long-term follow-up of this as well as additional cases. 相似文献
680.
By aid of fluorescent centromere markers in chromosome No. 3 it could be shown that crossing over in a translocation quadrivalent had occurred on two occasions in a father who is carrier of a 3/5 translocation. This case demonstrates that marker chromosomes cannot always be used to trace the parental origin of structurally abnormal chromosomes. 相似文献