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181.
The hamadryas baboon, Papio hamadryas hamadryas, represents a rare exception from the pattern of female philopatry and male-biased dispersal predominant in mammals including primates. To elucidate the possible consequences of the dispersal pattern on the population genetic structure of hamadryas baboons, we sequenced the maternally transmitted mitochondrial hypervariable region I of 74 individuals from ten sampling locations in different ecogeographic zones of Eritrea. To this end, individual fecal samples were collected at sleeping cliffs. Upon comparing the individual sequences by means of phylogenetic tree reconstructions and AMOVA, we could not detect a population genetic structure corresponding to a geographic pattern. Tree reconstructions revealed the existence of two profoundly different lineages both present at most of the sampling locations. These findings and Mantel correlations of genetic distances and the frequency of shared haplotypes to geographic distances point to the presence of female dispersal. Female-mediated gene flow is detectable over geographic distances exceeding those between neighboring subpopulations. Our study therefore corroborates local behavioral observations on a broad geographic scale. After inclusion of geographically closely situated olive baboons, P. h. anubis, in the analyses, all anubis sequences fell within one hamadryas clade. Possible scenarios leading to this situation including long-term hybridization processes are discussed. 相似文献
182.
To determine nutritional and social influences on life history traits and mating behavior in female langur monkeys, new long-term data for a feral population living in multi-male groups under poor nutritional conditions are presented and compared with published long-term data for the same species living in one-male groups under excellent nutritional conditions. Under poor nutritional conditions, conceptions were confined to 5 months per year, coinciding with the period of the highest mating activity. Age at first parturition, gestation periods, lactation periods, and interbirth intervals were all significantly increased resulting in a more than 50% reduced reproductive rate under poor conditions. The pattern of sexual behavior during gestation was influenced by neither nutritional nor social conditions but the frequency was higher in multi-male groups. Furthermore, estrus length was significantly increased in multi-male groups where females tended to mate with as many resident males as available. Both phenomena, together with a high percentage of sexual behavior occurring outside the mid-cycle estrus, are interpreted in the light of paternity confusion in multi-male groups in a species where infanticide by males is regularly observed. The extreme variation in life history traits and mating patterns disclosed here in one species suggests that future cross-species comparisons should strictly select datasets based on local ecological and social conditions. 相似文献
183.
Krein A Audinot JN Migeon HN Hoffmann L 《Environmental science and pollution research international》2007,14(1):3-4
Background, Aim and Scope
Current scientific studies and evaluations clearly show that an increase of urban dust loads, alone or combined with other
pollutants und certain meteorological conditions lead to different significant health effects. Premature death, increased
hospital admissions and increased respiratory symptoms and diseases as well as decreased lung function can be observed in
combination with high pollutant levels. Sensitive groups like elderly people or children and persons with cardiopulmonary
diseases such as asthma are more strongly affected. Because of the direct contact between fine particles and lung tissue more
information concerning the surface structure (mapping of toxic elements) is required.
Materials and Methods:
The NanoSims50 ion microprobe images the element composition at the surface of sub-micrometer air dust particles and documents
hot spots of toxic elements as a possible threat for human health.
Results:
The atmospheric fine dust consists of a complex mixture of organic and inorganic compounds. Heavy metals are fixed on airborn
particles in the form of hot spots in a nanometer scale. From a sanitary point of view, the hot spots consisting of toxic
elements are particularly relevant as they react directly with the lung tissues.
Discussion:
To what extent particles can penetrate the various areas of the lungs and be deposited there depends on the one hand on their
physical characteristics and on the other on breathing patterns and the anatomy of the lung, which is subject to change as
the result of growth, ageing or illness. Once inhaled, some particles can reach the pulmonary alveoli and thus directly expose
the lung tissues to toxic elements.
Conclusions:
Especially the mapping of toxic arsenic or heavy metals like copper on the dust particles shows local hot spots of pollution
in the dimension of only 50 nanometers.
Recommendations and Perspectives:
Imaging of elements in atmospheric particles with NanoSIMS will help to identify the material sources. 相似文献
184.
This study shows the important role of humic acids in the degradation of 14C and 13C labeled isomer of NP by Sphingomonas sp. strain TTNP3 and the detoxification of the resulting metabolites. Due to the association of NP with humic acids, its solubility in the medium was enhanced and the extent of mineralization of nonylphenol increased from 20% to above 35%. This was accompanied by the formation of significant amounts of NP residues bound to the humic acids, which also occurred via abiotic reactions of the major NP metabolite hydroquinone with the humic acids. Gel permeation chromatography showed a non-homogenous distribution of NP residues with humic acids molecules, with preference towards molecules with high-molecular-weight. Solid state 13C nuclear magnetic resonance spectroscopy indicated that the nonextractable residues resulted exclusively from the metabolites. The chemical shifts of the labeled carbon indicated the possible covalent binding of hydroquinone to the humic acids via ester and possibly ether bonds, and the incorporation of degradation products of hydroquinone into the humic acids. This study provided evidences for the mediatory role of humic acids in the fate of NP as a sink for bacterial degradation intermediates of this compound. 相似文献
185.
Brigitte Simon-Bouy Agnès Taillandier Delphine Fauvert Isabelle Brun-Heath Jean-Louis Serre Carmen G. Armengod Martin G. Bialer Michèle Mathieu Jacques Cousin David Chitayat Jan Liebelt Barbara Feldman Marion Gérard-Blanluet Stefani Körtge-Jung Cath King Hannele Laivuori Martine Le Merrer Sarju Mehta Christina Jern Saba Sharif Fabienne Prieur Gabriele Gillessen-Kaesbach Andreas Zankl Etienne Mornet 《黑龙江环境通报》2008,28(11):993-998
186.
Andreas Albrecht Katja Kiel Annette Kolk 《International journal of occupational safety and ergonomics》2007,13(2):201-213
In 2004/2005, a European Twinning Project was carried out to support Polish occupational safety and health institutions in putting into practice Directive 2000/54/EC regarding the protection of workers from risks related to exposure to biological agents at work. Information on and training in sampling and analysing biological agents of people responsible for bioaerosol measurements and the assessment of measuring results from the workplace atmosphere were part of the project. This paper is an extract of the authors' activities within the project and can be used as a tool for comparable activities in future projects with other European Union candidates. It gives information on working standards for bioaerosol measurements worked out and commonly used in Germany within the frame of European guidelines for bioaerosol measurements in the workplace atmosphere. Additionally it summarizes the authors' long practical experience in carrying out bioaerosol measurements in the atmosphere of various workplaces. 相似文献
187.
188.
Szolar OH Rost H Hirmann D Hasinger M Braun R Loibner AP 《Journal of environmental quality》2004,33(1):80-88
Sequential supercritical fluid (CO2) extraction (SSFE) was applied to eight historically contaminated soils from diverse sources with the aim to elucidate the sorption-desorption behavior of high molecular weight polycyclic aromatic hydrocarbons (PAHs). The method involved five extraction phases applying successively harsher conditions by increasing fluid temperature and density mobilizing target compounds from different soil particle sites. Two groups of soils were identified based on readily desorbing (available) PAH fractions obtained under mildest extraction conditions (e.g., readily desorbing fractions of fluoranthene and pyrene significantly varied between the soils ranging from <10 to >90%). Moreover, extraction behavior strongly correlated with molecular weight revealing decreasing available PAH fractions with increasing weight. Physicochemical soil parameters such as particle size distribution and organic dry mass were found to have no distinct effect on the sorption-desorption behavior of PAHs in the different soils. However, PAH profiles significantly correlated with readily available pollutant fractions; soils with relatively less mobile PAHs had higher proportions of five- and six-ring PAHs and vice versa. Eventually, biodegradability corresponded well with PAH recoveries under the two mildest extraction phases. However, a quantitative relationship was only established for soils with biodegradable PAHs. Out of eight soils, five showed no biodegradation including the four soils with the lowest fraction of readily desorbing PAHs. Only one soil (which was found to be highly toxic to Vibrio fischeri) did not match the overall pattern showing no PAH biodegradability but large fractions of highly mobile PAHs, concluding that mass transfer limitations may only be one of many factors governing biodegradability of PAHs. 相似文献
189.
Andreas Vermeulen Sierk Engels Klaus Peter Sauer 《Behavioral ecology and sociobiology》2008,63(1):77-83
Variation in traits closely related to fitness is expected to be low. This is because these traits are under directional selection
and the best genotype should prevail. However, there have been a number of studies demonstrating the existence of considerable
variance in sexually selected traits, which is generally known as the lek paradox. Accordingly, earlier studies found substantial
variation in sperm transfer rates in Panorpa vulgaris. Aiming at finding the mechanism that maintains this variation, we analyzed the condition dependence and the narrow sense
heritability of sperm transfer rates. Food deprivation in the larval/adult phase caused a decrease in the males’ capability
of saliva secretion resulting in shorter copulations and a reduced number of transferred sperm. There was a positive correlation
between mean sperm transfer rates and mean body mass. Additionally, intermale variation in sperm transfer rates decreased
with increasing food availability. Hence, we suggest that sperm transfer rates in P. vulgaris are influenced by adult feeding history. Heritability analyses of sperm transfer rates did not provide significant results,
which is consistent with the general hypothesis that additive genetic variance in traits closely related to fitness is small.
Since a trait’s potential to respond to selection is proportional to the amount of contained additive genetic variance, the
ascertained small heritability provides a satisfying explanation for the maintenance of substantial variation in sperm transfer
rates. 相似文献
190.