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Author (up) Arai, L. file  url
openurl 
  Title Peer and neighbourhood influences on teenage pregnancy and fertility: qualitative findings from research in English communities Type Journal Article
  Year 2007 Publication Health & Place Abbreviated Journal Health Place  
  Volume 13 Issue 1 Pages 87-98  
  Keywords Abortion, Induced/utilization; Adolescent; Adult; Attitude to Health/*ethnology; Birth Rate; England; Female; Geography; Humans; Interviews as Topic; Mothers/education/psychology; *Peer Group; Pregnancy; Pregnancy in Adolescence/*ethnology/psychology; Qualitative Research; Residence Characteristics/*classification; *Social Class; *Social Conformity; Social Values/ethnology; Socioeconomic Factors  
  Abstract Geographic variation in teenage pregnancy is attributable to social and cultural, as well as demographic, factors. In some communities and social networks early childbearing may be acceptable, or even normative. It is these places that are the focus of policy initiatives. This paper reports the findings of a qualitative study of neighbourhood and peer influences on the transition from pregnancy to fertility among 15 young mothers in three English locations. Data were also collected from nine local health workers. The findings show that, from the mothers' perspective, there was no evidence that peers influenced behaviour. However, the data did suggest that early childbearing might be normative in some communities.  
  Call Number Serial 1343  
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Author (up) Armstrong-Brown, J.; Eng, E.; Hammond, W.P.; Zimmer, C.; Bowling, J.M. file  url
openurl 
  Title Redefining racial residential segregation and its association with physical activity among African Americans 50 years and older: a mixed methods approach Type Journal Article
  Year 2015 Publication Journal of Aging and Physical Activity Abbreviated Journal J Aging Phys Act  
  Volume 23 Issue 2 Pages 237-246  
  Keywords African Americans/*statistics & numerical data; Age Factors; Aged; Attitude to Health/*ethnology; Cross-Sectional Studies; Exercise/*physiology; Female; Geography; Humans; Interviews as Topic; Life Style; Male; Middle Aged; Motor Activity/*physiology; Multivariate Analysis; Racism/ethnology/*statistics & numerical data; Regression Analysis; Risk Assessment; Sex Factors; Time Factors; United States  
  Abstract Physical inactivity is one of the factors contributing to disproportionate disease rates among older African Americans. Previous literature indicates that older African Americans are more likely to live in racially segregated neighborhoods and that racial residential segregation is associated with limited opportunities for physical activity. A cross-sectional mixed methods study was conducted guided by the concept of therapeutic landscapes. Multilevel regression analyses demonstrated that racial residential segregation was associated with more minutes of physical activity and greater odds of meeting physical activity recommendations. Qualitative interviews revealed the following physical activity related themes: aging of the neighborhood, knowing your neighbors, feeling of safety, and neighborhood racial identity. Perceptions of social cohesion enhanced participants' physical activity, offering a plausible explanation to the higher rates of physical activity found in this population. Understanding how social cohesion operates within racially segregated neighborhoods can help to inform the design of effective interventions for this population.  
  Call Number Serial 1292  
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Author (up) Brierley, A.S.; Kingsford, M.J. file  url
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  Title Impacts of climate change on marine organisms and ecosystems Type Journal Article
  Year 2009 Publication Current Biology : CB Abbreviated Journal Curr Biol  
  Volume 19 Issue 14 Pages R602-14  
  Keywords Animals; Carbon Dioxide/*chemistry; Demography; *Ecosystem; *Geography; *Greenhouse Effect; Marine Biology; Oceans and Seas; Population Dynamics; *Temperature; Climate change  
  Abstract Human activities are releasing gigatonnes of carbon to the Earth's atmosphere annually. Direct consequences of cumulative post-industrial emissions include increasing global temperature, perturbed regional weather patterns, rising sea levels, acidifying oceans, changed nutrient loads and altered ocean circulation. These and other physical consequences are affecting marine biological processes from genes to ecosystems, over scales from rock pools to ocean basins, impacting ecosystem services and threatening human food security. The rates of physical change are unprecedented in some cases. Biological change is likely to be commensurately quick, although the resistance and resilience of organisms and ecosystems is highly variable. Biological changes founded in physiological response manifest as species range-changes, invasions and extinctions, and ecosystem regime shifts. Given the essential roles that oceans play in planetary function and provision of human sustenance, the grand challenge is to intervene before more tipping points are passed and marine ecosystems follow less-buffered terrestrial systems further down a spiral of decline. Although ocean bioengineering may alleviate change, this is not without risk. The principal brake to climate change remains reduced CO(2) emissions that marine scientists and custodians of the marine environment can lobby for and contribute to. This review describes present-day climate change, setting it in context with historical change, considers consequences of climate change for marine biological processes now and in to the future, and discusses contributions that marine systems could play in mitigating the impacts of global climate change.  
  Call Number Serial 2155  
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Author (up) Callaway, R.M.; Brooker, R.W.; Choler, P.; Kikvidze, Z.; Lortie, C.J.; Michalet, R.; Paolini, L.; Pugnaire, F.I.; Newingham, B.; Aschehoug, E.T.; Armas, C.; Kikodze, D.; Cook, B.J. file  url
openurl 
  Title Positive interactions among alpine plants increase with stress Type Journal Article
  Year 2002 Publication Nature Abbreviated Journal Nature  
  Volume 417 Issue 6891 Pages 844-848  
  Keywords Atmospheric Pressure; Biomass; *Ecosystem; Geography; Plant Development; *Plant Physiological Phenomena; Reproduction; Species Specificity; Temperature; Stress  
  Abstract Plants can have positive effects on each other. For example, the accumulation of nutrients, provision of shade, amelioration of disturbance, or protection from herbivores by some species can enhance the performance of neighbouring species. Thus the notion that the distributions and abundances of plant species are independent of other species may be inadequate as a theoretical underpinning for understanding species coexistence and diversity. But there have been no large-scale experiments designed to examine the generality of positive interactions in plant communities and their importance relative to competition. Here we show that the biomass, growth and reproduction of alpine plant species are higher when other plants are nearby. In an experiment conducted in subalpine and alpine plant communities with 115 species in 11 different mountain ranges, we find that competition generally, but not exclusively, dominates interactions at lower elevations where conditions are less physically stressful. In contrast, at high elevations where abiotic stress is high the interactions among plants are predominantly positive. Furthermore, across all high and low sites positive interactions are more important at sites with low temperatures in the early summer, but competition prevails at warmer sites.  
  Call Number Serial 2154  
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Author (up) Mulholland, P.J.; Helton, A.M.; Poole, G.C.; Hall, R.O.; Hamilton, S.K.; Peterson, B.J.; Tank, J.L.; Ashkenas, L.R.; Cooper, L.W.; Dahm, C.N.; Dodds, W.K.; Findlay, S.E.G.; Gregory, S.V.; Grimm, N.B.; Johnson, S.L.; McDowell, W.H.; Meyer, J.L.; Valett, H.M.; Webster, J.R.; Arango, C.P.; Beaulieu, J.J.; Bernot, M.J.; Burgin, A.J.; Crenshaw, C.L.; Johnson, L.T.; Niederlehner, B.R.; O'Brien, J.M.; Potter, J.D.; Sheibley, R.W.; Sobota, D.J.; Thomas, S.M. file  url
openurl 
  Title Stream denitrification across biomes and its response to anthropogenic nitrate loading Type Journal Article
  Year 2008 Publication Nature Abbreviated Journal Nature  
  Volume 452 Issue 7184 Pages 202-205  
  Keywords Agriculture; Bacteria/metabolism; Computer Simulation; *Ecosystem; Geography; *Human Activities; Nitrates/*analysis/*metabolism; Nitrites/*analysis/*metabolism; Nitrogen/analysis/metabolism; Nitrogen Isotopes; Plants/metabolism; Rivers/*chemistry; Urbanization  
  Abstract Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter groundwater and surface waters. Large-scale nitrogen budgets show that an average of about 20-25 per cent of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins, indicating that substantial sinks for nitrogen must exist in the landscape. Streams and rivers may themselves be important sinks for bioavailable nitrogen owing to their hydrological connections with terrestrial systems, high rates of biological activity, and streambed sediment environments that favour microbial denitrification. Here we present data from nitrogen stable isotope tracer experiments across 72 streams and 8 regions representing several biomes. We show that total biotic uptake and denitrification of nitrate increase with stream nitrate concentration, but that the efficiency of biotic uptake and denitrification declines as concentration increases, reducing the proportion of in-stream nitrate that is removed from transport. Our data suggest that the total uptake of nitrate is related to ecosystem photosynthesis and that denitrification is related to ecosystem respiration. In addition, we use a stream network model to demonstrate that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks.  
  Call Number Serial 2107  
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Author (up) Pellerin, A.; Lacelle, D.; Fortin, D.; Clark, I.D.; Lauriol, B. file  url
doi  openurl
  Title Microbial diversity in endostromatolites (cf. Fissure Calcretes) and in the surrounding permafrost landscape, Haughton impact structure region, Devon Island, Canada Type Journal Article
  Year 2009 Publication Astrobiology Abbreviated Journal Astrobiology  
  Volume 9 Issue 9 Pages 807-822  
  Keywords Actinobacteria/genetics; Arctic Regions; Bacteria/classification/isolation & purification; *Biodiversity; Calcium Carbonate/*chemistry; Canada; Clone Cells; Desert Climate; Exobiology; Geography; *Ice; Microscopy, Electron, Scanning; Phylogeny; Proteobacteria/genetics; Soil Microbiology  
  Abstract In recent years, endostromatolites, which consist of finely laminated calcite columns that grow orthogonally within millimeter- to centimeter-thick fissures in limestone bedrock outcrops, have been discovered in dolomitic outcrops in the Haughton impact structure region, Devon Island, Canada. The growth mechanism of the endostromatolites is believed to be very slow and possibly intertwined with biotic and abiotic processes. Therefore, to discern how endostromatolites form in this polar desert environment, the composition of the microbial community of endostromatolites was determined by means of molecular phylogenetic analysis and compared to the microbial communities found in the surrounding soils. The microbial community present within endostromatolites can be inferred to be (given the predominant metabolic traits of related organisms) mostly aerobic and chemoheterotrophic, and belongs in large part to the phylum Actinobacteria and the subphylum Alphaproteobacteria. The identification of these bacteria suggests that the conditions within the fissure were mostly oxidizing during the growth of endostromatolite. The DNA sequences also indicate that a number of bacteria that closely resemble Rubrobacter radiotolerans are abundant in the endostromatolites as well as other Actinobacteria and Alphaproteobacteria. Some of these taxa have been associated with calcite precipitation, which suggests that the endostromatolites might in fact be microbially mediated. Bacterial communities from nearby permanently frozen soils were more diverse and harbored all the phyla found in the endostromatolites with additional taxa. This study on the microbial communities preserved in potentially microbially mediated secondary minerals in the Arctic could help in the search for evidence of life-forms near the edge of habitability on other planetary bodies.  
  Call Number Serial 221  
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Author (up) Powell, M.L.; Watts, S.A. file  url
openurl 
  Title Effect of temperature acclimation on metabolism and hemocyanin binding affinities in two crayfish, Procambarus clarkii and Procambarus zonangulus Type Journal Article
  Year 2006 Publication Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology Abbreviated Journal Comp Biochem Physiol A Mol Integr Physiol  
  Volume 144 Issue 2 Pages 211-217  
  Keywords Acclimatization/*physiology; Animals; Astacoidea/*metabolism; Basal Metabolism; *Body Temperature Regulation; Carrier Proteins/metabolism; Climate; Ecosystem; Female; Geography; Hemocyanin/*metabolism; Isoelectric Focusing; Male; Oxygen Consumption; Temperature  
  Abstract Procambarus clarkii and Procambarus zonangulus are two of the most widespread crayfish species in North America. In regions where their ranges overlap species composition can vary greatly. The physiological basis for this variable species composition is unknown. Temperature and oxygen level are two parameters that vary in shallow water habitats. We examined the metabolic rate and hemocyanin binding affinities in relation to thermal history. Temperature acclimation did not have the predicted effect on metabolic rate. Acclimation to high temperature (30 degrees C) decreased metabolic rate at 35 degrees C for both species. Low temperature acclimation (10 degrees C) resulted in 20% mortality in P. clarkii and 100% mortality in P. zonangulus when exposed to 35 degrees C. The range of P. clarkii is known to extend farther south than that of P. zonangulus, and this response may be a consequence of adaptations to higher temperatures in this range. Hemocyanin binding affinity was directly affected by assay and acclimation temperature. The highest P(50) values were recorded for crayfish of both species acclimated to 10 degrees C and assayed at 30 degrees C. There was also a shift in the isoelectric points of hemolymph proteins (possibly due to structural changes) that correlated with and an increase in the hemocyanin binding affinity following acclimation to high temperatures (30 degrees C) in both species.  
  Call Number Serial 1339  
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Author (up) Robine, J.-M.; Herrmann, F.R.; Arai, Y.; Willcox, D.C.; Gondo, Y.; Hirose, N.; Suzuki, M.; Saito, Y. file  url
openurl 
  Title Exploring the impact of climate on human longevity Type Journal Article
  Year 2012 Publication Experimental Gerontology Abbreviated Journal Exp Gerontol  
  Volume 47 Issue 9 Pages 660-671  
  Keywords Aged, 80 and over; Agriculture; Climate; Environment; Female; Geography; Humans; Japan; Longevity--physiology; Male; Mortality; Residence Characteristics; Seasons; Sex Factors; Socioeconomic Factors  
  Abstract The purpose of this study was to examine the impact of physical geographic factors and climate conditions on human longevity. The centenarian rate (CR) in 2005 was computed for Japan's 47 prefectures, whose geography and climate vary greatly. Several pathways, such as excess winter mortality, land use and agricultural production, possibly linking physical and climate factors with extreme longevity, were explored. The probability of becoming a centenarian varies significantly among the Japanese prefectures. In particular, the computation of CR(70) demonstrated that the actual probability for individuals 70 years old in 1975 of becoming centenarians in 2005 was 3 times higher, on average, in Okinawa, both for males and females, than in Japan as a whole. About three quarters of the variance in CR(70) for females and half for males is explained by the physical environment and land use, even when variations in the level of socio-economic status between prefectures are controlled. Our analysis highlighted two features which might have played an important role in the longevity observed in Okinawa. First, there is virtually no winter in Okinawa. For instance, the mean winter temperature observed in 2005 was 17.2 degrees C. Second, today, there is almost no rice production in Okinawa compared to other parts of Japan. In the past, however, production was higher in Okinawa. If we consider that long term effects of harsh winters can contribute to the mortality differential in old age and if we consider that food availability in the first part of the 20th century was mainly dependent on local production, early 20th century birth cohorts in Okinawa clearly had different experiences in terms of winter conditions and in terms of food availability compared to their counterparts in other parts of Japan. This work confirms the impact of climate conditions on human longevity, but it fails to demonstrate a strong association between longevity and mountainous regions and/or air quality.  
  Call Number Serial 482  
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