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CLARE D. FITZGIBBON 《Mammal Review》1995,25(1-2):19-30
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Cat gene frequencies in two Australian cities 总被引:2,自引:0,他引:2
B W Moffatt 《The Journal of heredity》1968,59(3):209-211
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Purpose
The cities merit special attention in global warming since they produce up to 80% of the global greenhouse gas emissions. Even though this has been widely acknowledged, only few papers exist that have studied cities holistically from a demand, i.e., consumption, perspective. The study presents a detailed analysis of the carbon footprint of two metropolitan cities from a consumption perspective. With the analysis of consumer carbon footprints (carbon consumption), the distribution of emissions in the key source categories is presented and compared. 相似文献5.
B. Padmanabhamurty 《International journal of biometeorology》1972,16(2):107-117
Climatic trends and effects on human health due to urbanization/industrialization of two Canadian cities during the last 30 years have been investigated. It was found that the frequency of thunderstorms, fog and smoke/haze days, cloud amount and dew point increased due to urbanization. Trends in mortality due to chronic bronchitis and neoplasm of the trachea lung and bronchus suggest a positive effect of meteorological parameters.
Zusammenfassung Die klimatischen Tendenzen während der letzten 30 Jahre als Folge der Urbanisation und Industrialisierung und ihre Wirkungen auf die menschliche Gesundheit wurden in 2 kanadischen Grossstädten untersucht. Dabei ergab sich, dass die Frequenzen von Gewittern, Nebel und Rauch/Dunst-Tagen, Wolkenmenge und Taupunkt als Folge der Urbanisation anstiegen. Die Entwicklung der Mortalität durch chronische Bronchitis und Neoplasma der Trachea, des Bronchus und der Lunge weisen auf einen positiven Einfluss der meteorologischen Parameter hin.
Resume On a cherché à circonscrire les modifications du climat qui se sont produites dans 2 grandes villes du Canada par suite de l'urbanisation et de l'industrialisation. On a cherché en outre à en exprimer les répercussions sur la santé de l'homme. Il ressort de cette étude qu'en raison de l'urbanisation, la fréquence des orages, du brouillard, des jours de brume industrielle et de points de rosée élevés a augmenté. Le sens des variations de la mortalité due aux bronchites chroniques et à la formation de tumeurs de la trachée, des bronches et des poumons montre une action directe des paramètres météorologiques.相似文献
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Localization of two antigenic determinants in histone H4 总被引:2,自引:0,他引:2
S Muller A Soussanieh J P Bouley J Reinbolt M H Van Regenmortel 《Biochimica et biophysica acta》1983,747(1-2):100-106
Four overlapping synthetic peptides corresponding to the carboxy-terminal region 80-102 of histone H4 were prepared by solid-phase peptide synthesis. Their antigenic activity was analysed by inhibition of the H4-anti-H4 reaction in complement fixation and enzyme-linked immunosorbent assay. One antigenic determinant was localized in residues 88-96 of the H4 molecule. No antigenic activity was found in peptides 80-89 and 97-102. Antibodies induced by peptide 85-102 were found to bind to free H4 in solution but not to chromatin subunits, suggesting a lack of accessibility of the C-terminal region of H4 in nucleosomes. A second epitope was found to be situated in the N-terminal region 1-53 of histone H4. 相似文献
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Urbanisation is increasing and it is essential to integrate biodiversity into the spatial planning of urban areas. This requires deeper understanding of biodiversity patterns in cities. We investigated which habitat variables are major determinants of dragonfly diversity and species assemblage structure in the municipal area of Dortmund (Germany). We sampled dragonfly larvae in 33 ponds situated in city parks, commercial, residential and agricultural areas. We recorded 30 autochthonous dragonfly species with species richness ranging from zero to 17. Additionally, we surveyed a set of environmental variables including habitat size, water level, pond structures and vegetation as well as surrounding landscape and potential disturbances like waterfowl and fish. Multivariate methods were used to identify the major determinants of dragonfly diversity, abundance and assemblage structure. Analysis indicated that diversity of aquatic and terrestrial vegetation affected dragonfly diversity positively. City park ponds had low diversity, but Ischnura elegans was obviously promoted by the specific park pond conditions, including high waterfowl density. We found five assemblages mostly determined by generalistic species which were related to different pond types. Moderately disturbed ruderal and pioneer ponds in residential and agricultural areas also contained increased numbers of rare species. Our results indicate that urban ponds may have a great value for maintaining biodiversity, but various disturbances have negative impact. To promote urban biodiversity we suggest a natural design of well-vegetated ponds as well as a high diversity of different pond types and particularly a more-natural redesign of city park ponds. 相似文献
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Two sympatric species of galago,Galago zanzibaricus andG. garnettii, differed significantly in diet (judged mainly by fecal analysis) and substrate use at each of two coastal forest sites in
Kenya. The larger-bodiedG. garnettii tended to use branches of a bigger diameter and to be found higher in the canopy than the smallerG. zanzibaricus. The latter species spent most of its time in the thick undergrowth. The larger species ate more fruit than the smaller.
There were differences between the species in the type of invertebrate prey remains found in the feces. It is suggested that
the differences in habitat use were influenced by the different body sizes of the two galagos, which so enabled these closely
related species to coexist.
Order of authorship is alphabetical. 相似文献
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PurposeA recent study using national data from 2000 to 2009 identified colorectal cancer (CRC) mortality “hotspots” in 11 counties of North Carolina (NC). In this study, we used more recent, state-specific data to investigate the county-level determinants of geographic variation in NC through a geospatial analytic approach.MethodUsing NC CRC mortality data from 2003 to 2013, we first conducted clustering analysis to confirm spatial dependence. Spatial economic models were then used to incorporate spatial structure to estimate the association between determinants and CRC mortality. We included county-level data on socio-demographic characteristics, access and quality of healthcare, behavioral risk factors (CRC screening, obesity, and cigarette smoking), and urbanicity. Due to correlation among screening, obesity and quality of healthcare, we combined these factors to form a cumulative risk group variable in the analysis.ResultsWe confirmed the existence of spatial dependence and identified clusters of elevated CRC mortality rates in NC counties. Using a spatial lag model, we found significant interaction effect between CRC risk groups and socioeconomic deprivation. Higher CRC mortality rates were also associated with rural counties with large towns compared to urban counties.ConclusionOur findings depicted a spatial diffusion process of CRC mortality rates across NC counties, demonstrated intertwined effects between SES deprivation and behavioral risks in shaping CRC mortality at area-level, and identified counties with high CRC mortality that were also deprived in multiple factors. These results suggest interventions to reduce geographic variation in CRC mortality should develop multifaceted strategies and work through shared resources in neighboring areas. 相似文献
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A telephone survey was conducted in Montreal and Calgary to determine the extent to which parents use safety restraints for their children in cars, the types of restraints used and the factors associated with such use. Of the combined sample 39% reported that their child regularly used a restraint, and 47% of the children in Montreal and 55% of those in Calgary wore an age-appropriate safety device. Birth order and the child''s and the respondent''s ages were significantly related to the use of restraints. However, the respondent''s use of seatbelts was the factor most likely to affect the rate of use of restraints for children. Although a large proportion of the parents with younger children owned a carseat, one in four did not use it regularly. Parents who did not use carseats believed they were useless or dangerous; many preferred to hold the child in their laps or arms. The seatbelt law in Quebec and the existence of a carseat rental program in Calgary appear to have had some influence on the rate of the use of restraints for children. 相似文献
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J V Neel C Satoh P Smouse J Asakawa N Takahashi K Goriki M Fujita T Kageoka R Hazama 《American journal of human genetics》1988,43(6):870-893
The results of 1,465,423 allele product determinations based on blood samples from Hiroshima and Nagasaki, involving 30 different proteins representing 32 different gene products, are analyzed in a variety of ways, with the following conclusions: (1) Sibships and their parents are included in the sample. Our analysis reveals that statistical procedures designed to reduce the sample to equivalent independent genomes do not in population comparisons compensate for the familial cluster effect of rare variants. Accordingly, the data set was reduced to one representative of each sibship (937,427 allele products). (2) Both chi 2-type contrasts and a genetic distance measure (delta) reveal that rare variants (P less than .01) are collectively as effective as polymorphisms in establishing genetic differences between the two cities. (3) We suggest that rare variants that individually exhibit significant intercity differences are probably the legacy of tribal private polymorphisms that occurred during prehistoric times. (4) Despite the great differences in the known histories of the two cities, both the overall frequency of rare variants and the number of different rare variants are essentially identical in the two cities. (5) The well-known differences in locus variability are confirmed, now after adjustment for sample size differences for the various locus products; in this large series we failed to detect variants at only three of 29 loci for which sample size exceeded 23,000. (6) The number of alleles identified per locus correlates positively with subunit molecular weight. (7) Loci supporting genetic polymorphisms are characterized by more rare variants than are loci at which polymorphisms were not encountered. (8) Loci whose products do not appear to be essential for health support more variants than do loci the absence of whose product is detrimental to health. (9) There is a striking excess of rare variants over the expectation under the neutral mutation/drift/equilibrium theory. We suggest that this finding is primarily due to the relatively recent (in genetic time) agglomeration of previously separated tribal populations; efforts to test for agreement with the expectations of this theory by using data from modern cosmopolitan populations are exercises in futility. (10) All of these findings should characterize DNA variants in exons as more data become available, since the finding are the protein expression of such variants. 相似文献
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Camille Mellin Bayden D. Russell Sean D. Connell Barry W. Brook Damien A. Fordham 《Diversity & distributions》2012,18(2):133-146
Aim We modelled the spatial abundance patterns of two abalone species (Haliotis rubra Donovan 1808 and H. laevigata Leach 1814) inhabiting inshore rocky reefs to better understand the importance of current sea surface temperature (SST) (among other predictors) and, ultimately, the effect of future climate change, on marine molluscs. Location Southern Australia. Methods We used an ensemble species distribution modelling approach that combined likelihood‐based generalized linear models and boosted regression trees. For each modelling technique, a two‐step procedure was used to predict: (1) the current probability of presence, followed by (2) current abundance conditional on presence. The resulting models were validated using an independent, spatially explicit dataset of abalone abundance patterns in Victoria. Results For both species, the presence of reef was the main driver of abalone occurrence, while SST was the main driver of spatial abundance patterns. Predictive maps at c. 1‐km resolution showed maximal abundance on shallow coastal reefs characterized by mild winter SSTs for both species. Main conclusions Sea surface temperature was a major driver of abundance patterns for both abalone species, and the resulting ensemble models were used to build fine‐resolution predictive range maps (c. 1 km) that incorporate measures of habitat suitability and quality in support of resource management. By integrating this output with structured spatial population models, a more robust understanding of the potential impacts of threatening human processes such as climate change can be established. 相似文献
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Crystal structures of two FGF-FGFR complexes reveal the determinants of ligand-receptor specificity 总被引:21,自引:0,他引:21
To elucidate the structural determinants governing specificity in fibroblast growth factor (FGF) signaling, we have determined the crystal structures of FGF1 and FGF2 complexed with the ligand binding domains (immunoglobulin-like domains 2 [D2] and 3 [D3]) of FGF receptor 1 (FGFR1) and FGFR2, respectively. Highly conserved FGF-D2 and FGF-linker (between D2-D3) interfaces define a general binding site for all FGF-FGFR complexes. Specificity is achieved through interactions between the N-terminal and central regions of FGFs and two loop regions in D3 that are subject to alternative splicing. These structures provide a molecular basis for FGF1 as a universal FGFR ligand and for modulation of FGF-FGFR specificity through primary sequence variations and alternative splicing. 相似文献
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Kenyan dominance in distance running 总被引:3,自引:0,他引:3
Larsen HB 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2003,136(1):161-170
Critical physiological factors for performance in running are maximal oxygen consumption (VO(2max)), fractional VO(2max) utilization and running economy. While Kenyan and Caucasian elite runners are able to reach very high, but similar maximal oxygen uptake levels, the VO(2max) of black South African elite runners seems to be slightly lower. Moreover, the studies of black and white South African runners indicate that the former are able to sustain the highest fraction of VO(2max) during long distance running. Results on adolescent Kenyan and Caucasian boys show that these boys are running at a similar percentage of VO(2max) during competition. Kenyan elite runners, however, appear to be able to run at a high % of VO(2max) which must then have been achieved by training. A lower energy cost of running has been demonstrated in Kenyan elite runners and in untrained adolescent Kenyan boys compared to their Caucasian counterparts. In agreement with this are the results from studies on black South African elite runners who have shown similar low energy costs during running as the Kenyan elite runners. The good running economy cannot be explained by differences in muscle fibre type as they are the same in Kenyan and Caucasian runners. The same is true when comparing untrained adolescent Kenyan boys with their Caucasian counterparts. A difference exists in BMI and body shape, and the Kenyans long, slender legs could be advantageous when running as the energy cost when running is a function of leg mass. Studies comparing the response to training of Kenyans and Caucasians have shown similar trainability with respect to VO(2max), running economy and oxidative enzymes. Taken all these data together it appears that running at a high fractional VO(2max) and having a good running economy may be the primary factors favouring the good performance of endurance athletes rather than them having a higher VO(2max) than other elite runners. In addition to having the proper genes to shape their bodies and thereby contributing to a good running economy, the Kenyan elite runners have trained effectively and used their potential to be in the upper range both in regard to VO(2max) and to a high utilization of this capacity during endurance running. 相似文献
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The chalcid wasps (Hymenoptera) that develop in fig tree inflorescences(Ficus: Moraceae) have often been used to study alternativereproductive behaviors. However, recent work suggests that suchbehaviors are more complex than previously thought. We investigatedthis in Otitesella longicauda and O. rotunda. In addition toknown dimorphisms in the two species (each have "religiosa"males that use their mandibles to fight for mates in the fig,and "digitata" males that disperse from the fig to mate), wefound that religiosa males below species-specific body sizeswitch points have relatively larger mandibles and are lesssclerotized than those above. Thus, they are actually trimorphic.We suggest that the religiosa morph variation is linked to fighter/nonfighteralternative mating behaviors, with small (nonfighting) maleshaving relatively larger mandibles because they also use themto pull females out of their galls before mating. Also, we investigatedthe determinants of wasp body size, and whether females (foundresses)adjust their offspring allocation strategies according to expectedoffspring size. We found that wasp size is larger in ovariesnear the center of the fig, and more females and fewer religiosamales are laid in such ovaries than in those further away. Thisprobably indicates that foundresses lay females when they areexpected to be large because their fitness is more body sizedependentthan that of religiosa males. We then discuss the implicationsof our findings for the study of alternative reproductive behaviorsand foundress offspring allocation strategies. 相似文献
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The proportion of people aged over 70 years in the community will, it is estimated, rise appreciably over the next 10 to 15 years. The impact, however, on different areas and different services will vary greatly. Using county based population projections this paper estimates the likely future demand by elderly people for home services in two contrasting general practices. To maintain services to meet the present demand, increases ranging from +11% to +55%, depending on the area and the service, will be required. 相似文献
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The nine leucine-rich repeat-containing exodomains of the human FSH receptor (hFSH-R) and the human LH/chorionic gonadotropin receptor (hLH-R) harbor molecular determinants that allow the mutually exclusive binding of human FSH (hFSH) and human LH (hLH)/human chorionic gonadotropin (hCG) when these hormones are present in physiological concentrations. Previously, we have shown that the beta-strands of hLH-R leucine-rich repeats 3 and 6 can confer full hCG/hLH responsiveness and binding when simultaneously introduced into a hFSH-R background without affecting the receptor's responsiveness to hFSH. In the present study, we have determined the nature of contribution of each of these two beta-strands in conferring hCG/hLH responsiveness to this mutant hFSH-R. Human LH-R beta-strand 3 appeared to function as a positive hCG/hLH determinant by increasing the hCG/hLH responsiveness of the hFSH-R. In contrast, mutagenesis of hFSH-R beta-strand 6, rather than the introduction of its corresponding hLH-R beta-strand, appeared to allow the interaction of hCG/hLH with the hFSH-R. Hence, hFSH-R beta-strand 6 functions as a negative determinant and, as such, restrains binding of hCG/hLH to the hFSH-R. Detailed mutagenic analysis revealed that the ability of the hFSH-R to interact with hCG/hLH depends primarily on the identity of two amino acids (Asn104, a positive LH-R determinant, and Lys179 a negative FSH-R determinant) that are situated on the C-terminal ends of beta-strands 3 and 6, respectively. 相似文献