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41.
The aim of our study was to assess the effects of aviation noise on reproduction and cub mortality in farmed blue foxes. Eighty artificially inseminated blue fox vixens (45 primiparous and 35 multiparous) were exposed to aviation noise on 5 days when they were pregnant or had cubs. The noise during the exposures varied from 85 to 121 dB (L(AFmax)). Vixens (45 primiparous and 34 multiparous) on a farm without flight action acted as controls. Cubs were counted 1, 3, 7, 14 and 49 days postpartum and at the beginning of July. Litter size (cubs per whelped vixen), reproductive performance (cubs per mated vixen) and cub losses (lost cubs per whelped vixen) were analyzed from both experimental farms (A and C). The flight action had no effect on reproductive success. Reproductive performance in primiparous vixens was 4.2+/-3.8 and 4.3+/-3.6 cubs (ns, Mann-Whitney U-test) in the control and aviation group, respectively, while in multiparous vixens the corresponding figures were 7.1+/-4.4 and 7.3+/-3.8 cubs (ns). In general, litter size declined from birth to weaning (in primiparous vixens from 8.1+/-3.8 to 5.4+/-3.2 cubs, and in multiparous from 9.7+/-3.8 to 7.2+/-3.8 cubs, P<0.001, GLM for repeated measures). The decline was greater in primiparous than in multiparous vixens (P<0.01). There were no differences in total cub losses between the experimental groups (ns). Accordingly, the present results show that exposure to severe and repeated aviation noise does not impair the reproductive success of farmed blue foxes.  相似文献   
42.
In the current study, the microbial ecology of weathered hydrocarbon and heavy metal contaminated soil undergoing phytoremediation was studied. The relationship of functional diversity, measured as carbon source utilisation in Biolog plates and extracellular enzymatic activities, and genetic diversity of bacteria was evaluated. Denaturing gradient gel electrophoresis was used for community analyses at the species level. Bulk soil and rhizosphere soil from pine and poplar plantations were analysed separately to determine if the plant rhizosphere impacted hydrocarbon degradation. Prevailing microbial communities in the field site were both genetically and metabolically diverse. Furthermore, both tree rhizosphere and fertilisation affected the compositions of these communities and increased activities of extracellular aminopeptidases. In addition, the abundance of alkane hydroxylase and naphthalene dioxygenase genes in the communities was low, but the prevalence of these genes was increased by the addition of bioavailable hydrocarbons. Tree rhizosphere communities had greater hydrocarbon degradation potential than those of bulk soil. Hydrocarbon utilising communities were dominated generally by the species Ralstonia eutropha and bacteria belonging to the genus Burkholderia. Despite the presence of viable hydrocarbon-degrading microbiota, decomposition of hydrocarbons from weathered hydrocarbon contaminated soil over four years, regardless of the presence of vegetation, was low in unfertilised soil. Compost addition enhanced the removal of hydrocarbons.  相似文献   
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Chromosomes of 228 captive specimens of the family Bovidae have been investigated. The examined animals were classified into the subfamilies Aepycerotinae, Reduncinae, Antilopinae, Alcelaphinae, Hippotraginae and Bovinae. Polymorphism for one fusion was identified in the species: Aepyceros melampus, 2n = 59–60; Redunca fulvorufula, 2n = 56–57; Kobus e. ellipsiprymnus, 2n = 50–52; Kobus e. defassa, 2n = 52–54 and Syncerus c. nanus, 2n = 54–55. This is the first study to reveal fusion 7;29 in Kobus e. defassa and simultaneously the respective polymorphism. Variation in the diploid number of chromosomes is also known in species: Oryx g. dammah and Oryx g. leucoryx but in this study only fusion 1;25 was identified in both karyotyped species. Our study showed that 13% of investigated individuals were polymorphic for the centric fusion and demonstrated the important role of cytogenetic screening in captive animals at zoological gardens.  相似文献   
45.
We evaluated how body fat percentage, measured by a portable near-infrared interactance (NIR) device predicts cardiovascular (CVD), coronary heart disease (CHD), and ischemic stroke events in a prospective population-based survey. The study population consisted of 2,842 men and 3,196 women, who participated in the FINRISK'92 survey. Obesity was assessed with BMI, waist circumference, and waist-to-hip ratio (WHR) and body fat percentage measured with an NIR. Mean length of follow-up was 9 years and 3 months. In Cox proportional hazards regression analyses for men, BMI, waist circumference, and WHR as well as body fat percentage were predictors of a CVD event when adjusted for age and for major risk factors. Hazard ratio (HR) per 1 s.d. was 1.27 (95% confidence interval: 1.10-1.48) for body fat percentage, 1.30 (1.16-1.46) for BMI, and 1.31 (1.16-1.50) for waist circumference. Among women, the body fat lost its predictive power in a fully adjusted model. Body fat percentage, BMI, waist circumference, and WHR were predictors of a CHD event both among men and women, whereas body fat percentage did not predict ischemic stroke among either gender. We observed that body fat percentage measured by an NIR device was a significant predictor of CVD and CHD events among men and women, but in our population-based survey, it did not provide any additional predictive power over and above the simpler measures, such as BMI or WHR.  相似文献   
46.
Understanding the interaction between the nervous system and cerebral vasculature is fundamental to forming a complete picture of the neurophysiology of sleep and its role in maintaining physiological homeostasis. However, the intrinsic hemodynamics of slow-wave sleep (SWS) are still poorly known. We carried out 30 all-night sleep measurements with combined near-infrared spectroscopy (NIRS) and polysomnography to investigate spontaneous hemodynamic behavior in SWS compared to light (LS) and rapid-eye-movement sleep (REM). In particular, we concentrated on slow oscillations (3-150 mHz) in oxy- and deoxyhemoglobin concentrations, heart rate, arterial oxygen saturation, and the pulsation amplitude of the photoplethysmographic signal. We also analyzed the behavior of these variables during sleep stage transitions. The results indicate that slow spontaneous cortical and systemic hemodynamic activity is reduced in SWS compared to LS, REM, and wakefulness. This behavior may be explained by neuronal synchronization observed in electrophysiological studies of SWS and a reduction in autonomic nervous system activity. Also, sleep stage transitions are asymmetric, so that the SWS-to-LS and LS-to-REM transitions, which are associated with an increase in the complexity of cortical electrophysiological activity, are characterized by more dramatic hemodynamic changes than the opposite transitions. Thus, it appears that while the onset of SWS and termination of REM occur only as gradual processes over time, the termination of SWS and onset of REM may be triggered more abruptly by a particular physiological event or condition. The results suggest that scalp hemodynamic changes should be considered alongside cortical hemodynamic changes in NIRS sleep studies to assess the interaction between the autonomic and central nervous systems.  相似文献   
47.

Background  

Escherichia coli induces the heat shock response to a temperature up-shift which is connected to the synthesis of a characteristic set of proteins, including ATP dependent chaperones and proteases. Therefore the balance of the nucleotide pool is important for the adaptation and continuous function of the cell. Whereas it has been observed in eukaryotic cells, that the ATP level immediately decreased after the temperature shift, no data are available for E. coli about the adenosine nucleotide levels during the narrow time range of minutes after a temperature up-shift.  相似文献   
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49.
Loss-of-function mutations of the MECP2 gene at Xq28 are associated with Rett syndrome in females and with syndromic and nonsyndromic forms of mental retardation (MR) in males. By array comparative genomic hybridization (array-CGH), we identified a small duplication at Xq28 in a large family with a severe form of MR associated with progressive spasticity. Screening by real-time quantitation of 17 additional patients with MR who have similar phenotypes revealed three more duplications. The duplications in the four patients vary in size from 0.4 to 0.8 Mb and harbor several genes, which, for each duplication, include the MR-related L1CAM and MECP2 genes. The proximal breakpoints are located within a 250-kb region centromeric of L1CAM, whereas the distal breakpoints are located in a 300-kb interval telomeric of MECP2. The precise size and location of each duplication is different in the four patients. The duplications segregate with the disease in the families, and asymptomatic carrier females show complete skewing of X inactivation. Comparison of the clinical features in these patients and in a previously reported patient enables refinement of the genotype-phenotype correlation and strongly suggests that increased dosage of MECP2 results in the MR phenotype. Our findings demonstrate that, in humans, not only impaired or abolished gene function but also increased MeCP2 dosage causes a distinct phenotype. Moreover, duplication of the MECP2 region occurs frequently in male patients with a severe form of MR, which justifies quantitative screening of MECP2 in this group of patients.  相似文献   
50.
The aims of this work were to develop a high-rate fluidized-bed bioprocess for ferric sulfate production, to characterize biomass retention, and to determine the phylogeny of the enrichment culture. After 7 months of continuous enrichment and air aeration at 37 degrees C, the iron oxidation rate of 8.2 g Fe(2+) L(-1)h(-1) (4.5.10(-12) g Fe(2+) cell(-1) h(-1)) was obtained at a hydraulic retention time (HRT) of 0.6 h. However, oxygen supply became the rate-limiting factor. With gas mixture (99.5% O(2)/0.5% CO(2) (vol/vol)) aeration and HRT of 0.2 h, the iron oxidation rate was 26.4 g Fe(2+) L(-1)h(-1) (1.0.10(-11) g Fe(2+) cell(-1) h(-1)). Leptospirillum sp. was predominant in the mesophilic fluidized-bed reactor (FBR) enrichment culture as determined by fluorescent in situ hybridization, while Acidithiobacillus ferrooxidans was not detected. Denaturing gradient gel electrophoresis (DGGE) of the amplified partial 16S rDNA showed only three bands, indicating a simple microbial community. DGGE fragment excision and sequencing showed that the populations were related to L. ferriphilum (100% similarity in sequence) and possibly to the genus Ferroplasma (96% similarity to F. acidiphilum). Jarosite precipitates accumulated on the top of the activated carbon biomass carrier material, increasing the rate of iron oxidation. The activated carbon carrier material, jarosite precipitates, and reactor liquid contained 59% (or 3.71.10(9) cells g(-1)), 31% (or 3.12.10(10) cells g(-1)) and 10% (or 1.24.10(8) cells mL(-1)) of the total FBR microbes, respectively, demonstrating that the jarosite precipitates played an important role in the FBR biomass retention.  相似文献   
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