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61.
The availability of suitable habitat is a key predictor of the changing status of biodiversity. Quantifying habitat availability over large spatial scales is, however, challenging. Although remote sensing techniques have high spatial coverage, there is uncertainty associated with these estimates due to errors in classification. Alternatively, the extent of habitats can be estimated from ground‐based field survey. Financial and logistical constraints mean that on‐the‐ground surveys have much lower coverage, but they can produce much higher quality estimates of habitat extent in the areas that are surveyed. Here, we demonstrate a new combined model which uses both types of data to produce unified national estimates of the extent of four key habitats across Great Britain based on Countryside Survey and Land Cover Map. This approach considers that the true proportion of habitat per km2 (Zi) is unobserved, but both ground survey and remote sensing can be used to estimate Zi. The model allows the relationship between remote sensing data and Zi to be spatially biased while ground survey is assumed to be unbiased. Taking a statistical model‐based approach to integrating field survey and remote sensing data allows for information on bias and precision to be captured and propagated such that estimates produced and parameters estimated are robust and interpretable. A simulation study shows that the combined model should perform best when error in the ground survey data is low. We use repeat surveys to parameterize the variance of ground survey data and demonstrate that error in this data source is small. The model produced revised national estimates of broadleaved woodland, arable land, bog, and fen, marsh and swamp extent across Britain in 2007.  相似文献   
62.
Eight novel microsatellite primer pairs are presented for Penstemon rostriflorus, representing the first microsatellite markers available for this genus. Loci were characterized for 20 individuals from two populations in the Great Basin, USA. All loci are polymorphic within P. rostriflorus (seven to 13 alleles per locus; observed heterozygosity between 0.40 and 0.95), and therefore useful for population genetic studies within the species. Cross‐species transferability was tested on 40 additional species of Penstemon, and results indicate that these primers pairs will likely be useful for population genetic studies on many Penstemon species.  相似文献   
63.
Objective: Prior studies have reported ethnic differences in adiponectin and ghrelin, but few have assessed the role of body size in normoglycemic women. We compared fasting adiponectin and ghrelin concentrations in normoglycemic 40‐ to 80‐year‐old Filipino, African‐American, and white women. Methods: Participants included women from the Rancho Bernardo Study (n = 143), the University of California‐San Diego Filipino Women's Health Study (n = 136), and the Health Assessment Study of African‐American Women (n = 212). A 2‐hour oral glucose tolerance test was administered; glucose, insulin, lipid, and anthropometric measurements were obtained. Fasting adiponectin and ghrelin were measured by radioimmunoassay. Results: Whites and Filipinas had similar BMI (23.7 and 24.3 kg/m2, respectively), waist girth (75.6 and 77.2 cm, respectively), and total body fat (27.4 and 28.5%, respectively); African‐Americans had significantly larger BMI (28.8 kg/m2), waist girth (86.3 cm), and body fat (39.6%, p < 0.0001). Adiponectin was lower in Filipinas (8.90 µg/mL) and African‐Americans (9.67 µg/mL) compared with whites (15.6 µg/mL, p < 0.001) after adjusting for age, homeostasis model assessment of insulin resistance (HOMA‐IR), and waist‐to‐hip ratio. Compared with whites, Filipinas (β = ?5.06, p < 0.0001) and African‐Americans (β = ?6.85, p < 0.0001) had significantly lower adiponectin levels after adjusting for age, waist‐to‐hip ratio, HOMA‐IR, triglycerides, high‐density lipoprotein (HDL) cholesterol, exercise, and alcohol use. Ghrelin was significantly lower in Filipinas compared with African‐Americans (1146.9 vs. 1412.2 pg/mL, p < 0.001), and this observation persisted in multivariable analysis (β = ?245.4, p < 0.0001). Ghrelin levels did not differ between whites (1356.9 pg/mL) and either ethnic group. Discussion: Normoglycemic Filipino and African‐American women had significantly lower adiponectin concentrations than white women, and Filipinas had lower ghrelin levels than African‐Americans, independently of body size or indices of insulin resistance or lipids.  相似文献   
64.
Trematode parasites have complex life cycles and use a variety of host species across different trophic levels. Thus, they can be used as indicators of disturbance and recovery of coastal ecosystems. Estuaries on the Pacific coast of northeastern Japan were heavily affected by the 2011 Tohoku earthquake tsunami. To evaluate the effect of the tsunami on the trematode community, we examined trematodes in the mud snail, Batillaria attramentaria, at five study sites (three sites severely exposed to the tsunami and two sites sheltered from the tsunami) in Sendai Bay for 2 years prior to and 8 years after the tsunami. While the trematode prevalence decreased at all study sites, the species richness decreased only at the sites exposed to the tsunami. Although parasitism increased over the study period post-tsunami, the community had not fully recovered 8 years after the event. Trematode community structure has changed every year since the tsunami and has not stabilised. This could be explained by the alteration of first and second intermediate host communities. Our study suggests that it will take more time for the recovery of the trematode community and the associated coastal ecosystem in the Tohoku region.  相似文献   
65.
We used mitochondrial DNA to assess the genetic structure of endangered lake chubsucker Erimyzon sucetta across its Canadian range. We found unique mitochondrial haplotypes in Lyons Creek, a tributary of the Niagara River that faces a strong potential for habitat deterioration. Lyons Creek may therefore serve as a reservoir of unique genetic diversity. The sensitivity of Lyons Creek, combined with the genetic uniqueness of its E. sucetta population, call for further investigation into whether this population should be considered a separate designatable unit for conservation purposes.  相似文献   
66.
The African citrus triozid (ACT), Trioza erytreae Del Guercio, is a destructive pest particularly on citrus, and vectors, “Candidatus” Liberibacter africanus (CLaf), which is the causal agent of the African citrus greening disease. Our study seeks to establish the distribution and host‐plant relationship of ACT across citrus production areas in Kenya. We also modelled the risk of spread using the maximum entropy modelling algorithm with known occurrence data. Our results infer that ACT is widely distributed and causes severe damage to four alternative host plants belonging to the family Rutaceae. The adults, immature stages (eggs and nymphs), galls and the percentage of infested leaves were significantly higher in shaded than unshaded trees. However, adult ACTs preferred Kenyan highlands to Victoria Lake and coastal regions. The average area under the curve of the model predictions was 0.97, indicating an optimal model performance. The environmental variables that most influenced the prediction were the precipitation of wettest quarter, precipitation of wettest month, mean diurnal range, temperature seasonality and mean temperature of the coldest quarter. The current prediction of ACT exceeded its existing range, especially in the Western, Nyanza, Central, Rift valley and Eastern regions of Kenya. The model predicted a contraction of suitable habitats for a potential spread in 2040 with an inland shift to higher altitudes in the cooler regions. The potential for further expansion to climatically suitable areas was more pronounced for the 2080 forecast. These findings provide relevant information to improve monitoring/surveillance and designing IPM strategies to limit its spread and damage.  相似文献   
67.
68.
Genetic structure of the Berba of Benin was studied on the basis of biodemographic data and ABO, RH, MNS, KEL, JK, FY, ACP1, ADA, AK1, CA2, ESD, GLO1, G6PD, PGD, PGM1 (subtypes and thermostability), PGM2, PGP, SODA, HBα, HBβ, HBδ, BF, C3, and Hp gene frequencies. Comparisons were carried out with other populations of Benin and of sub-Sahara Africa. Correspondence analysis revealed genetic differentiation among the three main groups of populations who inhabit sub-Saharan Africa: Bushmen-Hottentots, Pygmies, and Negroes. The genetic differentiation of the Negroes in relation to their linguistic affiliation and geographic localization was evident. The first group included the populations belonging to the Bantoid subfamily of the Nigritic linguistic stock living in southern Africa; in the second subcluster the populations of central-eastern Africa were localized, and the third subcluster included the populations living in the West. © 1996 Wiley-Liss, Inc.  相似文献   
69.
Skeletal remains of 47 individuals from the Great Salt Lake Wetlands, affiliated principally with Bear River (A.D. 400—1000) and Levee Phase (A.D. 1000—1350) Fremont cultural elements, were assessed for four mitochondrial DNA (mtDNA) markers that, in particular association, define four haplogroups (A, B, C, and D) widely shared among contemporary Amerindians groups. The most striking result is the absence of haplogroup A in this Fremont series, despite its predominance in contemporary Amerindian groups. Additionally, haplogroup B, defined by the presence of a 9bp deletion in region V, is present at the moderately high frequency of 60%. Haplogroups C and D are present at low frequencies. An additional haplotype, "N, observed in some modern populations and two other prehistoric samples, is also present in this Fremont skeletal collection. © 1996 Wiley-Liss, Inc.  相似文献   
70.
为了探究ASFV E248R蛋白调控cGAS-STING信号通路的机制,利用双荧光素酶报告系统验证ASFV E248R蛋白够剂量依赖性地抑制cGAS-STING和HT-DNA诱导的IFN-β的产生。通过相对定量PCR技术验证,过表达E248R抑制IFNB1、RANTES、IL-6和TNF-αβ基因的转录水平。免疫共沉淀和激光共聚焦试验结果表明,E248R与STING相互作用。通过蛋白印迹试验证实,过表达E248R可抑制STING的表达。研究表明ASFV E248R蛋白通过抑制STING的表达拮抗天然免疫应答。该结果将扩展对ASF免疫逃逸的认知,为疫苗的研制提供新的思路。  相似文献   
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