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Anthropogenic structures and installations in wild areas are known to directly and indirectly affect wildlife populations, especially apex predators such as Eagle Owls (Bubo bubo). To understand the situation at the national level we analyzed data collected by the Scientific Data Department of the Israel Nature and Parks Authority and the wildlife hospital at the Safari in Ramat Gan. We analyzed a total of 189 dead Eagle Owls during fifteen years, 2007–2021; 39.7% were electrocuted, 29.2% roadkill, 12.7% flew into fences/barbed wire, 3.8% drowned, and 14.9% died from other causes. The largest mortality of the Eagle Owls was detected in agricultural (34.92 %) and urban areas (31.74%). Also, the pylons identified as lethal should be prioritized and modified with appropriate insulators. Only a sincere effort on the part of the authorities will the continued electrocution of eagle owls and other avian wildlife be truncated.  相似文献   

3.
Background: The causes of renal cell cancer (RCC) remain largely unexplained. While the incidence is generally higher in men than in women, little has been reported on ethnic differences. We examine trends in RCC incidence and mortality rates among Israeli Arab and Jewish populations and compared with the rates in other countries. Methods: Age-adjusted RCC incidence and mortality rates in Israel, during 1980–2004, were calculated by sex and population group, using the National Cancer Registry. They were compared with the United States based on the Surveillance Epidemiology and End Results [SEER] program and the IARC database for international comparisons. Results: While RCC incidence rates in Israel are similar to the United States and the European average, the rates are significantly higher among Israeli Jews than Arabs. Men are affected more than women. Incidence rates over the last 24 years have increased among all men and Jewish women, but not among Arab women. Among men, the incidence rate ratio for Jews to Arabs declined from 3.96 in 1980–1982 to 2.34 in 2001–2004, whereas for women there was no change. The mortality rates were higher among Jews than Arab and among men than women. There were no significant change in the mortality rates and rate ratios. Conclusions: Our findings demonstrate marked ethnic differences in RCC in Israel. The lower incidence among Arabs stands in contrast to the higher prevalence of potential risk factors for RCC in this population group. Genetic factors, diet and other lifestyle factors could play protective roles.  相似文献   

4.
Background: The patterns of primary liver cancer incidence and survival are not known for detailed ethnic groups within the UK. Methods: Data on patients resident in England diagnosed with primary liver cancer (ICD-10 C22) between 2001 and 2007 were extracted from the National Cancer Data Repository. Age-standardised incidence rate ratios (IRRs) were calculated for different ethnic groups separately for males and females, using the White ethnic groups as baselines. Overall survival was analysed using Cox regression, adjusting sequentially for age, socioeconomic deprivation and co-morbidity. Results: Ethnicity data were available for 75% (13,139/17,458) of primary liver cancer patients. Compared with the White male baseline, Chinese males had the highest IRR. Black African, Bangladeshi, Pakistani and Indian men also had statistically significant high IRRs. Black Caribbean men had a marginally elevated incidence rate compared with White men. In comparison with White women, Pakistani women had the highest IRR. Bangladeshi, Chinese, Black African and Indian women also had high IRRs. As observed in men, Black Caribbean women had an incidence rate closer to that of White women. Pakistani men and women, Black African women and Chinese men had statistically significantly better survival compared with their White counterparts. Conclusion: The variation found in the incidence of primary liver cancer, could be due to established risk factors such as hepatitis B and C infection being more prevalent among certain ethnic groups. Country of birth, age at migration and length of stay in England are likely to be important factors in this disease, and future research should examine these where possible.  相似文献   

5.
Members of the Borrelia burgdorferi sensu lato (s.l.) species complex are known to cause human Lyme borreliosis. Because of longevity of some reservoir hosts and the Ixodes tick vectors' life cycle, long-term studies are required to better understand species and population dynamics of these bacteria in their natural habitats. Ticks were collected between 1999 and 2010 in three ecologically different habitats in Latvia. We used multilocus sequence typing utilizing eight chromosomally located housekeeping genes to obtain information about species and population fluctuations and/or stability of B. burgdorferi s.l. in these habitats. The average prevalence over all years was 18.9%. From initial high-infection prevalences of 25.5%, 33.1% and 31.8%, from 2002 onwards the infection rates steadily decreased to 7.3%. Borrelia afzelii and Borrelia garinii were the most commonly found genospecies but striking local differences were obvious. In one habitat, a significant shift from rodent-associated to bird-associated Borrelia species was noted whilst in the other habitats, Borrelia species composition was relatively stable over time. Sequence types (STs) showed a random spatial and temporal distribution. These results demonstrated that there are temporal regional changes and extrapolations from one habitat to the next are not possible.  相似文献   

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Background

So-called atypical scrapie was first identified in Great Britain (GB) in 2002 following the introduction of wide-scale scrapie surveillance. In particular, abattoir and fallen stock surveys have been carried out in GB since 2002, with a total of 147 atypical positives identified by the end of 2006. The results of these surveys provide data with which to assess temporal trends in the prevalence of atypical scrapie in sheep in Great Britain between 2002 and 2006.

Results

Using the results of abattoir and fallen stock surveys, the prevalence of atypical scrapie (percentage of samples positive) was estimated. The prevalence in the abattoir and fallen stock surveys, for all years combined, was 0.09% (95% confidence interval (CI): 0.08%–0.11%) and 0.07% (95% CI: 0.05%–0.11%), respectively. There were no significant temporal trends in either survey. Comparing the surveys' results, there were no significant differences in annual prevalence or the prevalence within PrP genotypes. For the abattoir survey, the PrP genotype with the highest prevalence was AHQ/AHQ, which was significantly higher than all other genotypes, except ARR/AHQ, AHQ/ARH and ARH/ARQ.

Conclusion

The estimated prevalence of atypical scrapie was similar in both the abattoir and fallen stock surveys. Our results indicate there was no significant temporal trend in prevalence, adding to evidence that this atypical form of scrapie may be a sporadic condition or, if it is infectious, that the force of infection is very low.
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8.
Changes in the annual population densities of Ceratium spp. in three adjacent English lakes, Windermere, Esthwaite Water and Blelham Tarn, are summarised over the 41 year period 1945–1985. In these lakes the genus is represented by two species, C. hirundinella (O.F. Müll) Bergh. and C. furcoides (Levander) Langhans. Although the species have not been distinguished over the entire study period, they have been shown by examination of preserved samples to undergo marked changes of relative abundance in Esthwaite Water. Both long-term (years) and short-term (within year) changes of populations densities of Ceratium spp. are considered in relation to possible controlling factors including recruitment of the inoculum, nutrient enrichment, physical stability and fungal epidemics. Given an early inoculum, the relative success of Ceratium populations in these lakes decreases along gradients of increasing mixed depths, increasing turbulence and decreasing retention times. The potential for good population growth is regulated by energy inputs, lake bathymetry and hydraulic characteristics. The realisation of such growth is governed by nutrient availability and microbial grazing. The significance of large between-year differences of populations of Ceratium spp. for general lake metabolism is illustrated for summers of contrasting production in Esthwaite Water.  相似文献   

9.

Background

The epidemiology of pneumococcal meningitis in the African ‘meningitis belt’ is poorly studied. In order to ensure an effective vaccination strategy and post-vaccination surveillance, we examined the serotype distribution patterns of pneumococcal meningitis in Niger over the period 2003–2011.

Methods

Cerebrospinal fluid (CSF) samples were collected from different health facilities throughout Niger in the frame of the national microbiological surveillance of meningitis. Determination of the serotype of CSF positive for pneumococci was performed using a sequential multiplex PCR method (SM-PCR) adapted with a national algorithm in which 32 different serotypes were covered and grouped into eight consecutive PCR.

Results

The SM-PCR assay could predict the Sp serotype for 779 CSF (88.7%), 98 CSF (11.3%) were not-typeable in our national-adapted algorithm. In total, 26 different serotypes were identified. Serotype 1 (n = 393) was the most prevalent and accounted for 45.3% of infections, followed by serogroups/serotypes 12F/(12A)/(44)/(46) (7.3%), 6/(6A/6B/6C/6D) (5.4%), 14 (5.2%), 5 (4.6%), 23F (4.2%), 45 (3.6%), 2 (3.1%), 18/(18A/18B/18C/18F) (2.9%) and 17 others serotypes with a prevalence of less than 2%. The proportion of serotype 1 in infants(<2 years old) represented only 4.3% of the cases affected by this serotype. In contrast, serotypes 5, 6, 14, 19A and 23F were only detected in very young children.

Conclusions

The proportion of serotype 1 in the pneumococcal meningitis cases and the theoretical vaccine coverage across all age groups advocates for the introduction of a conjugate vaccine (PCV10 or 13) into the Expanded Programme on Immunization (EPI) in Niger. Post-vaccine introduction surveillance supported by molecular approaches will be essential to provide a comprehensive picture of the impact of the vaccine on the burden reduction of pneumococcal meningitis and on pneumococcal serotype distribution.  相似文献   

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As a corollary to the Red Queen hypothesis, host–parasite coevolution has been hypothesized to maintain genetic variation in both species. Recent theoretical work, however, suggests that reciprocal natural selection alone is insufficient to maintain variation at individual loci. As highlighted by our brief review of the theoretical literature, models of host–parasite coevolution often vary along multiple axes (e.g. inclusion of ecological feedbacks or abiotic selection mosaics), complicating a comprehensive understanding of the effects of interacting evolutionary processes on diversity. Here we develop a series of comparable models to explore the effect of interactions between spatial structures and antagonistic coevolution on genetic diversity. Using a matching alleles model in finite populations connected by migration, we find that, in contrast to panmictic populations, coevolution in a spatially structured environment can maintain genetic variation relative to neutral expectations with migration alone. These results demonstrate that geographic structure is essential for understanding the effect of coevolution on biological diversity.  相似文献   

12.
Hepatitis C virus (HCV) is an important cause of chronic liver disease. Several highly diverse HCV genotypes exist with potential key functional differences. The HCV NS5A protein was associated with response to interferon (IFN)-α based therapy, and is a primary target of currently developed directly-acting antiviral compounds. NS5A is important for replication and virus production, but has not been studied for most HCV genotypes. We studied the function of NS5A using infectious NS5A genotype 1–7 cell culture systems, and through reverse genetics demonstrated a universal importance of the amphipathic alpha-helix, domain I and II and the low-complexity sequence (LCS) I for HCV replication; the replicon-enhancing LCSI mutation S225P attenuated all genotypes. Mutation of conserved prolines in LCSII led to minor reductions in virus production for the JFH1(genotype 2a) NS5A recombinant, but had greater effects on other isolates; replication was highly attenuated for ED43(4a) and QC69(7a) recombinants. Deletion of the conserved residues 414-428 in domain III reduced virus production for most recombinants but not JFH1(2a). Reduced virus production was linked to attenuated replication in all cases, but ED43(4a) and SA13(5a) also displayed impaired particle assembly. Compared to the original H77C(1a) NS5A recombinant, the changes in LCSII and domain III reduced the amounts of NS5A present. For H77C(1a) and TN(1a) NS5A recombinants, we observed a genetic linkage between NS5A and p7, since introduced changes in NS5A led to changes in p7 and vice versa. Finally, NS5A function depended on genotype-specific residues in domain I, as changing genotype 2a-specific residues to genotype 1a sequence and vice versa led to highly attenuated mutants. In conclusion, this study identified NS5A genetic elements essential for all major HCV genotypes in infectious cell culture systems. Genotype- or isolate- specific NS5A functional differences were identified, which will be important for understanding of HCV NS5A function and therapeutic targeting.  相似文献   

13.
There has been little evidence of a decline in the global burden of cholera in recent years as the number of cholera cases reported to WHO continues to rise. Cholera remains a global threat to public health and a key indicator of lack of socioeconomic development. Overall socioeconomic development is the ultimate solution for control of cholera as evidenced in developed countries. However, most research has focused on cross-county comparisons so that the role of individual- or small area-level socioeconomic status (SES) in cholera dynamics has not been carefully studied. Reported cases of cholera in Matlab, Bangladesh have fluctuated greatly over time and epidemic outbreaks of cholera continue, most recently with the introduction of a new serotype into the region. The wealth of longitudinal data on the population of Matlab provides a unique opportunity to explore the impact of socioeconomic status and other demographic characteristics on the long-term temporal dynamics of cholera in the region. In this population-based study we examine which factors impact the initial number of cholera cases in a bari at the beginning of the 0139 epidemic and the factors impacting the number of cases over time. Cholera data were derived from the ICDDR,B health records and linked to socioeconomic and geographic data collected as part of the Matlab Health and Demographic Surveillance System. Longitudinal zero-inflated Poisson (ZIP) multilevel regression models are used to examine the impact of environmental and socio-demographic factors on cholera counts across baris. Results indicate that baris with a high socioeconomic status had lower initial rates of cholera at the beginning of the 0139 epidemic (γ01 = −0.147, p = 0.041) and a higher probability of reporting no cholera cases (α01 = 0.156, p = 0.061). Populations in baris characterized by low SES are more likely to experience higher cholera morbidity at the beginning of an epidemic than populations in high SES baris.  相似文献   

14.
Natural enemy–victim systems may exhibit a range of dynamic space–time patterns. We used a theoretical framework to study spatiotemporal structuring in a transient natural enemy–victim system subject to differential rates of dispersal, stochastic forcing, and nonlinear dynamics. Highly mobile natural enemies that attacked less mobile victims were locally spatially segregated from each other when governed by approximate linear dynamics. In contrast, in nonlinear dynamical systems, such as cyclic populations, interacting species achieved local aggregation with each other regardless of dispersal rates, and aggregation was enhanced specifically when highly mobile enemies attacked less mobile victims. These patterns of spatial aggregation held under varying levels of stochastic forcing. This work thus shows a range of dynamic spatial patterns in interacting-species models, and how spatial aggregation between natural enemies and victims can be achieved in locally unstable populations that are linked through dispersal.  相似文献   

15.
《Aquatic Botany》1987,27(2):177-186
Potamogeton pectinatus L. populations were studied at three stations over an annual cycle.The maximum standing crop of 17.5 g dry weight (wt.) m−2 was recorded a the most sheltered station, decreasing slightly at the intermediate station to 15.8 g dry wt.m−2, and being only 4.8 g dry wt.m−2 at the most exposed station.Flowering and seed production occurred at all three stations. The maximum proportion of dry weight allocated to reproduction was higher at the more exposed stations (4%), while at the sheltered station only 1% was allocated to reproductive parts. The number of overwintering tubers produced per m2 decreased from 115 per m2 to 45 per m2 with lowered exposure. Conversely, the number of flowers per inflorescence and flowers per m2 was highest at the most sheltered station, decreasing from 9 to 6 and 945 to 672 per m2, respectively, with increasing exposure. No definite trend could be found for seed production, which was highly variable and dependent on a successful period of fertilization during calm weather. At the sheltered locality more resources were allocated to vegetative shoots and rhizomes which were also able to overwinter.The resource allocation of Potamogeton pectinatus seems to be strongly influenced by environmental factors. This is discussed in relation to current reproductive strategy concepts.  相似文献   

16.
Seasonal and annual movements of Australian waterbirds are generally more complex than those of their Northern Hemisphere counterparts, and long-term data are needed to understand their relationships with climatic variables. This paper explores a long-term (1973–2002) set of waterbird counts from coastal Victoria and relates them to climatic data at local and continental scales. Three species (Black Swan Cygnus atratus, White-faced Heron Egretta novaehollandiae and Grey Teal Anas gracilis) were chosen for this analysis. Black Swans have large local breeding populations near the study region; White-faced Herons have smaller local breeding populations and Grey Teal breed extensively in ephemeral inland floodplains, such as those in the Murray-Darling Basin. All showed significant relationships with streamflow, regional rainfall and the Southern Oscillation Index (SOI) at appropriate scales and time-lags, with streamflow explaining the most variance. Black Swans showed a strong seasonal cycle in abundance and local climate variables had the greatest influence on the counts. Numbers were positively correlated with streamflow in southern Victoria three to six seasons before each count. Broader-scale climatic patterns were more important for the other two species. Numbers of White-faced Herons were positively correlated with streamflow or rainfall over various parts of Australia seven to nine seasons before each count. Numbers of Grey Teal showed weak seasonal cycles, and were negatively correlated with rainfall in Victoria or the Murray-Darling Basin in the seasons before or during each count, and positively with streamflow in the Murray-Darling Basin 15–18 months before each count.  相似文献   

17.
Schreiber A 《Heredity》2002,89(3):163-170
Twenty-nine allozyme loci analyzed in 295 common gudgeons (Gobio gobio) from the Rhine, the upper Danube and the Elbe river systems revealed variability measures of P = 0.590, H(e) = 0.066, and G(ST) = 0.1415. Gene flow was estimated at N(e)m = 1.88 over 223 river km in the Danube basin, and at N(e)m = 1.96 over 300 river km in the Rhine system. Isolation-by-distance was not observed. Danubian gudgeons proved significantly more heterozygous (H(e) = 0.106) than those from the Rhine (H(e) = 0.057) or the Elbe drainages (H(e) = 0.029). Nine polymorphic enzymes contributed to this difference, which probably indicates dispersal bottlenecking of the postglacial immigrants into the Atlantic drainages of the study area. Refugial bottlenecking of gudgeons from Atlantic drainages in a Pleistocene refuge located in oceanic northwest Europe also seems possible. Slightly deeper genetic lineages in the Danube (G(ST) = 0.0859) than in the Rhine (G(ST) = 0.0793) agree with this explanation, as does the greater mean genetic distance among pairs of population samples from the Danube (D = 0.0138) than from the Rhine (D = 0.0054). A genetic distance of D = 0.0085 separated Rhenish and Danubian gudgeons.  相似文献   

18.
The spatial diversity and distribution of AM fungi were investigated in three plots located in farming–pastoral zone, north China. The rhizospheres of Caragana korshinskii, Artemisia sphaerocephala and Salix psammophila were sampled and thirty AM fungal species belonging to five genera were isolated. The study demonstrated that AM fungal diversity and distribution differed significantly among the three host plants and the three studied plots. Spore density of AM fungi ranged between 2 and 22 spores per g?1 of soil and species richness between 8 and 23. Correlation coefficient analysis demonstrated that spore density was significantly and positively correlated with soil organic matter and available N (P?<?0.01). Species richness was significantly and positively correlated with soil organic matter and available P (P?<?0.01), but significantly and negatively correlated with soil pH (P?<?0.01). Finally, the Shannon–Weiner index was significantly and positively correlated with soil organic matter (P?<?0.05). In this farming–pastoral zone, Glomus reticulatum and G.melanosporum may be more adaptable to the arid conditions than other AM fungal species. This research into AM fungal diversity may lead to exploitation of AM fungi for the mitigation of soil erosion and desertification using mycorrhizal plants, such as C.korshinskii, A.sphaerocephala and S. psammophila. The results of this study support the conclusion that diversity and distribution of AM fungi might be useful to monitor desertification and soil degradation.  相似文献   

19.

Background

Socioeconomic inequalities in childhood obesity have been reported in most developed countries, with obesity more common in deprived groups. Whether inequalities are found in the prevalence of underweight, the rest of the body mass index (BMI) distribution, or have changed across time is not clear.

Methods and Findings

The sample comprised 5,027,128 children on entry (4 to 5 years old) and leaving (10 to 11 years) state primary (elementary) school who participated in the National Child Measurement Programme (England, United Kingdom). We used area-level deprivation (Indices of Multiple Deprivation at the lower super output area) as a measure of socioeconomic deprivation. From 2007–2008 to 2011–2012 inequalities in obesity between the most compared to least deprived group increased (from 7.21% to 8.30%; p<0.001), whereas inequalities in the prevalence of underweight (1.50% to 1.21%; p = 0.15) were stable during this period. There were no differences by age group or by sex, but a three-way interaction suggested inequalities in obesity had increased at a faster rate for 10 to 11 year old girls, than 4 to 5 year old boys, (2.03% vs 0.07%; p<0.001 for interaction). Investigating inequalities across the distribution of zBMI showed increases in mean zBMI (0.18 to 0.23, p<0.001) could be attributed to increases in inequalities between the 50th and 75th centiles of BMI. Using the 2011 to 2012 population attributable risk estimates, if inequalities were halved, 14.04% (95% CI 14.00% to 14.07%) of childhood obesity could be avoided.

Conclusions

Socioeconomic inequalities in childhood obesity and zBMI increased in England between 2007–2008 and 2011–2012. Inequalities in the prevalence of underweight did not change. Traditional methods of examining inequalities only at the clinical thresholds of overweight and obesity may have led the magnitude of inequalities in childhood BMI to be underestimated.  相似文献   

20.
Bioremediation of arsenic (As) pollution is an important environmental issue. The present investigation was carried out to isolate As-resistant novel bacteria and characterize their As transformation and tolerance ability. A total of 170 As-resistant bacteria were isolated from As-contaminated soils at the Kangjiawan lead–zinc tailing mine, located in Hunan Province, southern China. Thirteen As-resistant isolates were screened by exposure to 260 mM Na2HAsO4·7H2O, most of which showed a very high level of resistance to As5+ (MIC?≥?600 mM) and As3+ (MIC?≥?10 mM). Sequence analysis of 16S rRNA genes indicated that the 13 isolates tested belong to the phyla Firmicutes, Proteobacteria and Actinobacteria, and these isolates were assigned to eight genera, Bacillus, Williamsia, Citricoccus, Rhodococcus, Arthrobacter, Ochrobactrum, Pseudomonas and Sphingomonas. Genes involved in As resistance were present in 11 of the isolates. All 13 strains transformed As (1 mM); the oxidation and reduction rates were 5–30% and 10–51.2% within 72 h, respectively. The rates of oxidation by Bacillus sp. Tw1 and Pseudomonas spp. Tw224 peaked at 42.48 and 34.94% at 120 h, respectively. For Pseudomonas spp. Tw224 and Bacillus sp. Tw133, the highest reduction rates were 52.01% at 48 h and 48.66% at 144 h, respectively. Our findings will facilitate further research into As metabolism and bioremediation of As pollution by genome sequencing and genes modification.  相似文献   

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