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Winter activities on ice are culturally important for many countries, yet they constitute a high safety risk depending upon the stability of the ice. Because consistently cold periods are required to form stable and thick ice, warmer winters could degrade ice conditions and increase the likelihood of falling through the ice. This study provides the first large-scale assessment of winter drowning from 10 Northern Hemisphere countries. We documented over 4000 winter drowning events. Winter drownings increased exponentially in regions with warmer winters when air temperatures neared 0°C. The largest number of drownings occurred when winter air temperatures were between -5°C and 0°C, when ice is less stable, and also in regions where indigenous traditions and livelihood require extended time on ice. Rates of drowning were greatest late in the winter season when ice stability declines. Children and adults up to the age of 39 were at the highest risk of winter drownings. Beyond temperature, differences in cultures, regulations, and human behaviours can be important additional risk factors. Our findings indicate the potential for increased human mortality with warmer winter air temperatures. Incorporating drowning prevention plans would improve adaptation strategies to a changing climate.
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Afogamento/epidemiologia , Temperatura Alta , Gelo , Estações do Ano , Condução de Veículo , Criança , Humanos , Itália/epidemiologia , Estados Unidos/epidemiologia , Adulto JovemRESUMO
The cellulose binding domain (CBD) of cellulosome-integrating protein A from Clostridium thermocellum NBRC 103400 was genetically fused to FMN-dependent NADH-azoreductase (AZR) and glucose 1-dehydrogenase (GDH) from Bacillus subtilis. The fusion enzymes, AZR-CBD and CBD-GDH, were expressed in Escherichia coli Rosetta-gami B (DE3). The enzymes were purified from cell-free extracts, and the specific activity of AZR-CBD was 15.1 U/mg and that of CBD-GDH was 22.6 U/mg. AZR-CBD and CBD-GDH bound strongly to 0.5 % swollen cellulose at approximately 95 and 98 % of the initial protein amounts, respectively. After immobilization onto the swollen cellulose, AZR-CBD and CBD-GDH retained their catalytic activity. Both enzymes bound weakly to 0.5 % microcrystalline cellulose, but the addition of a high concentration of microcrystalline cellulose (10 %) improved the binding rate of both enzymes. A reactor for flow injection analysis was filled with microcrystalline cellulose-immobilized AZR-CBD and CBD-GDH. This flow injection analysis system was successfully applied for the determination of glucose, and a linear calibration curve was observed in the range of approximately 0.16-2.5 mM glucose, with a correlation coefficient, r, of 0.998.
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INTRODUCTION: In Canada, unique food security challenges are being faced by Aboriginal people living in remote-northern communities due to the impacts of climate change on subsistence harvesting. This study used traditional environmental knowledge (TEK) to investigate whether there was a temporal relationship between extreme climatic events in the summer of 2005, and fish die-offs in the Albany River, northern Ontario, Canada. Also, TEK was utilized to examine a potential shift in subsistence fish species distribution due to climate change. METHODS: To investigate whether there was a temporal relationship between the fish die-offs of July 2005 (as identified by TEK) and an extreme climatic event, temperature and daily precipitation data for Moosonee weather station were utilized. To determine if there was an increasing trend in mean maximal summer temperatures with year, temperature data were examined, using regression analysis. Present-day fish distributions were determined using unpublished TEK data collated from previous studies and purposive, semi-directive interviews with elders and experienced bushman. RESULTS: Fish die-offs in 2005 occurred during the time period 11-18 July, as reported by participants. Recorded air-temperature maxima of the two July 2005 heat waves delineate exactly the time period of fish die-offs. Two heat waves occurring during the same summer season and so close together has never before been recorded for this region. A highly significant (p < 0.0009) positive relationship between mean maximal summer temperatures and year was evident. Regionally novel fish species were not apparent, utilizing TEK. CONCLUSIONS: Traditional environmental knowledge coupled with climate data revealed temporal relationships between extreme climatic events in 2005, and fish die-offs in the Albany River. Thus, climate change can directly impact food security by decreasing the number of fish through mortality - and indirectly through population dynamics - by impacting the yield of fish subsistence harvests in the future. By contrast, TEK did not reveal northward expansion of novel fish species in the Albany River or fish distributional contraction in the western James Bay region.
Assuntos
Mudança Climática , Saúde Ambiental/educação , Peixes , Abastecimento de Alimentos/estatística & dados numéricos , Indígenas Norte-Americanos , Conhecimento , Animais , Cultura , Ecossistema , Humanos , Entrevistas como Assunto , Masculino , Ontário , TemperaturaRESUMO
The molecular motion of surface-immobilized double-decker phthalocyanine complexes was examined using STM. (C(8)OPc)(2)Ce (1), (C(12)OPc)(2)Ce (2), and (C(8)OPc)Ce(Pc) (3) double-decker complexes, of which two ligands contained Pc nuclei, formed well-ordered self-organized structures on their own. Square-shaped top Pc ligands were clearly observed for complexes 1, 2, and 3 even though free space presented around the top ligands caused by mixing the complexes with template molecules. However, the details of the shapes of the top ligands of complexes 1, 2, and 3 were changed by the surrounding environment. The surrounding environment was considered to have influenced the mobility of the top ligands. Another complex, (C(8)OPc)Ce(TPP) (4), had difficulty forming a self-organized structure by itself. Complex 4 could have been immobilized by coadsorbing on the substrate with the C(8)OPc template, but the intramolecular structure of the top ligands of complex 4 was difficult to observe. The results strongly suggested that combinations of molecules composed of double-decker complexes as well as the free space presented around a top ligand are important factors that control the molecular motion of immobilized double-decker complexes on solid surfaces.
Assuntos
Cério/química , Indóis/química , Compostos Organometálicos/química , Isoindóis , Ligantes , Microscopia de Tunelamento , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
The alkyl chain length on alkyl-substituted phthalocyanines (C(n)OPc) dependence of their self-organized structures was examined in this study. STM results indicated that the symmetry of ordered structures decreased as the alkyl chain became longer, with the exception of C(6)OPc, which preferentially formed a quasi-3-fold symmetrical structure. This could be explained by the fact that the C(n)OPc molecules are most likely to form densely packed structures. With C(n)OPc, when n = 4 to 10, the self-organized structures were dependent on the competition between how densely the molecules were arranged and how loose the intermolecular interaction energy was, caused by the formation of the densely packed structure. However, with C(n)OPc, when n = 10-18, the molecules tended to form densely packed structures by reducing the symmetry, even though the C(n)OPc molecules were distorted. When C(12)OPc and cobalt phthalocyanine were coadsorbed, the mixed system exhibited a four-fold symmetrical structure, which is rarely observed in C(12)OPc.