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991.
Maternal investment in rhesus macaques (Macaca mulatta): reproductive costs and consequences of raising sons 总被引:1,自引:0,他引:1
Maternal investment in offspring is expected to vary according to offspring sex when the reproductive success of the progeny
is a function of differential levels of parental expenditure. We conducted a longitudinal investigation of rhesus macaques
to determine whether variation in male progeny production, measured with both DNA fingerprinting and short tandem repeat marker
typing, could be traced back to patterns of maternal investment. Males weigh significantly more than females at birth, despite
an absence of sex differences in gestation length. Size dimorphism increases during infancy, with maternal rank associated
with son’s, but not daughter’s, weight at the end of the period of maternal investment. Son’s, but not daughter’s, weight
at 1 year of age is significantly correlated with adult weight, and male, but not female, weight accounts for a portion of
the variance in reproductive success. Variance in annual offspring output was three- to fourfold higher in males than in females.
We suggest that energetic costs of rearing sons could be buffered by fetal delivery of testosterone to the mother, which is
aromatized to estrogen and fosters fat accumulation during gestation. We conclude that maternal investment is only slightly
greater in sons than in daughters, with mothers endowing sons with extra resources because son, but not daughter, mass has
ramifications for offspring sirehood. However, male reproductive tactics supersede maternal investment patterns as fundamental
regulators of male fitness.
Received: 23 July 1999 / Received in revised form: 23 February 2000 / Accepted: 13 March 2000 相似文献
992.
In recent years, many electronic manufacturing firms have looked upon Cleaner Production (CP) as the means by which they could maintain environmental practice and competitive advantages. CP has been adopted by companies as an important factor in enhancing industrial productivity. Sustainable projects that deal appropriately with environmental and social factors are also more likely to be the most profitable.This paper investigated the criteria and attributes that determine a successful adoption and implementation of CP in reference to PWB manufacture in Taiwan. Fuzzy Analytic Hierarchy Process (FAHP) methodology is used to discuss the different decision criteria that include Organizing, Systems and Technologies, Measurement and Feedback, Working environment and Worker's Culture which are all vital factors in an effective CP implementation. AHP is an efficient tool in controlling the fuzziness of the data involved in choosing the most preferred decision variables. The linguistic level of comparisons produced by the manufacturers and experts are tapped and constructed in a form of triangular fuzzy numbers in order to construct fuzzy pairwise comparison matrices. The implementation of the system is demonstrated by a problem involving three stages of hierarchy which contains different criteria and attributes at a wider perspective within an environmental uncertainty. The findings advocate that these enterprises would need to setup the priorities of the CP implementation. The results suggest a generic hierarchical model of organizations of which the highest level is to be prioritized among the CP implementation factors. 相似文献
993.
994.
May TW Fairchild JF Petty JD Walther MJ Lucero J Delvaux M Manring J Armbruster M 《Environmental monitoring and assessment》2008,137(1-3):213-232
The Solomon River Basin is located in north-central Kansas in an area underlain by marine geologic shales. Selenium is an
indigenous constituent of these shales and is readily leached into the surrounding groundwater. Portions of the Basin are
irrigated primarily through the pumping of selenium-contaminated groundwater from wells onto fields in agricultural production.
Water, sediment, macroinvertebrates, and fish were collected from various sites in the Basin in 1998 and analyzed for selenium.
Selenium concentrations were analyzed spatially and temporally and compared to reported selenium toxic effect thresholds for
specific ecosystem components: water, sediments, food-chain organisms, and wholebody fish. A selenium aquatic hazard assessment
for the Basin was determined based on protocol established by Lemly. Throughout the Basin, water, macroinvertebrate, and whole
fish samples exceeded levels suspected of causing reproductive impairment in fish. Population structures of several fish species
implied that successful reproduction was occurring; however, the influence of immigration of fish from low-selenium habitats
could not be discounted. Site-specific fish reproduction studies are needed to determine the true impact of selenium on fishery
resources in the Basin.
The U.S. Government’s right to retain a non-exclusive, royalty free license in and to any copyright is acknowledged. 相似文献
995.
Collivignarelli C Tharnpoophasiam P Vaccari M De Felice V Di Bella V Mingkwan R 《Environmental monitoring and assessment》2008,147(1-3):191-198
University of Brescia and Mahidol University of Bangkok developed a project in Phang Nga province (Thailand), the most damaged by 2004 tsunami. In particular, the study, performed between April and May 2006, dealt with the surface and ground water monitoring in Ban Nam Khem village and the experimental evaluation of possible drinking treatment alternatives. The monitoring highlighted that saline content in the tsunami affected area is decreasing but still very high (conductivity presented values up to 2,600 and 6,230 microS/cm in ground and surface water, respectively); hence, advanced and complicated processes such as reverse osmosis should be adopted to treat such water for drinking purposes. Waiting for ground water salinity to assume acceptable values, activities for the reduction of its organic and microbiological contamination will be started. However, it has to be underlined that the diffusion of drinking water to a greater part of population can be obtained only through the realization of new centralised treatment plants and the improvement of existing ones (serving at the moment about 20% of inhabitants). 相似文献
996.
Multiresidue analysis of pesticides in fruits and vegetables by gas chromatography-mass spectrometry
Araoud M Douki W Rhim A Najjar MF Gazzah N 《Journal of environmental science and health. Part. B》2007,42(2):179-187
A multiresidue method was assessed for the determination of several pesticides (organochlorine, organophosphorus, pyrethroids, triazole, amidine) using gas chromatography/mass spectrometry. The extraction of pesticides was carried out by liquid-liquid extraction (LLE) and solid-phase extraction (SPE) using two types of columns (CN and C18). The extracts were cleaned by the addition of florisil, the pesticides were separated by capillary column gas chromatography and detected by mass spectrometry in the electron impact mode. The extraction using C18 column provided the best results for most of the analyzed pesticides. The majority of pesticides recoveries from the four fruits and vegetables (apples, pears, tomatoes and pepper) were greater than 60%. Linearity and precision were satisfactory. The estimated limits of detection and limits of quantification ranged from 0.01 to 0.1 mg/kg and from 0.02 to 0.3 mg/kg, respectively. The proposed procedure was found to be useful for the multiresidue analyses of pesticides in agricultural products for routine monitoring programs. 相似文献
997.
Rao PS Ansari MF Gavane AG Pandit VI Nema P Devotta S 《Environmental monitoring and assessment》2007,128(1-3):323-328
Petroleum refineries are largest chemical industries that are responsible for the emission of several pollutants into the
atmosphere. Benzene is among the most important air pollutants that are emitted by petroleum refineries, since they are involved
in almost every refinery process. Volatile organic compounds (VOCs) are a major group of air pollutants, which play a critical
role in atmospheric chemistry. These contribute to toxic oxidants, which are harmful to ecosystem, human health and atmosphere.
The variability of pollutants is an important factor in determining human exposure to these chemicals. The ambient air concentrations
of benzene were measured in several sites around the Digboi petroleum refinery, near the city of Gowahati in northeast India,
during winter and summer 2004. The seasonal and spatial variations of the ambient air concentrations of this benzene were
investigated and analyzed. An estimation of the contribution of the refinery to the measured atmospheric levels of benzene
was also performed. The ambient air mixing ratios of benzene in a large area outside the refinery was generally low, in ppbv
range, much lower than the ambient air quality standards. This article presents the temporal and spatial variation of air
pollution in and around petroleum refinery and showed that no health risk due to benzene is present in the areas adjacent
to the refinery. 相似文献
998.
H. C. Eaton M. B. Walsh M. E. Tittlebaum F. K. Cartledge D. Chalasani 《Environmental monitoring and assessment》1987,9(2):133-142
Liquid hazardous waste disposal in landfills is usually allowed only after solidification/stabilization. Although various procedures are commonly practiced, little is known about the mechanism(s) of the processes. A particular problem is the interference of organics. Small amounts of organics can interfere with the reaction between inorganic sludges and cementitous matrices. The present communication reports studies of the interaction between selected organic hazardous wastes and Type I Portland cement. Microscopic studies of the structural differences between cements set with water and those set with water plus organic liquids are discussed. In these studies the scanning electron microscope is used to observe samples fractured at 78K. The results provide technical background data on the ultimate stability of critical waste constituents solidified by various binding agents. 相似文献
999.
M K Siddiqui F Anjum S S Qadri 《Journal of environmental science and health. Part. B》1987,22(5):553-564
Effects of three different doses of endosulfan respectively designated as low, medium and high on cytochrome P450(Cyt.P450), glutathione S-transferase(GST) activity and glutathione content (GSH) of hepatic and extra hepatic tissues of rat were determined after 24 hours of treatment. Endosulfan caused induction of cyt. P450 in liver, lung and brain at all the three doses tested while in kidney, spleen and heart either induction or reduction took place and was unrelated with dosages of endosulfan. Similarly, GST activity significantly changed in extra hepatic tissues while liver GST activity did not record any significant alteration under the experimental conditions. The GSH content also showed changes (increase/decrease) unrelated to endosulfan dosages in different organs. Thus, the effects varied with organ and dosages. As these metabolic parameters are involved in biotransformation of many endogenous molecules as well, the study may throw some light on physiological disturbances due to changes in metabolizing system on one side and organ specificity in toxic action of endosulfan on the other. 相似文献
1000.
Thevenot M Dousset S Rousseaux S Andreux F 《Environmental pollution (Barking, Essex : 1987)》2008,153(1):148-156
The influence of different organic amendments on diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (diuron + metabolites) in the leachates of the VR soil (0.19-0.71%) was lower than in the Bj soil (4.27-8.23%), which could be explained by stronger diuron adsorption on VR. An increase in the amount of diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between diuron and water-extractable organic matter (WEOM) through the Bj soil, or by competition between diuron and WEOM for the adsorption sites in the soil. For both soils, the nature of the composts and their degree of maturity did not significantly influence diuron leaching. 相似文献