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1.
Setting universal goals for sustainability is problematic and may hinder the adoption of sustainable pathways as different sectors of society often have differing opinions on not just what sustainability means for them, but also what is of priority to them. This paper tests a set of psychographic, behavioural, lifestyle and social identities to segment the public on sustainability. We evaluate general knowledge, apply social-choice tools to identify public priorities, and then apply segmentation to reveal broad strata of community profiles around these choices. We discuss our findings in the context of moving beyond knowledge on sustainability and general public choices, to more nuanced messaging and engagement that respects differences in sustainability orientations. We suggest that by focusing on what matters most for different segments of society, there is potential to design effective processes to engage with people and acquire better ownership of sustainability.  相似文献   
2.
Pathogen-driven declines in animal populations are increasingly regarded as a major conservation issue. The Tasmanian devil (Sarcophilus harrisii) is threatened with extinction by devil facial tumor disease, a unique transmissible cancer. The disease is transmitted through direct transfer of tumor cells, which is possible because the genetic diversity of Tasmanian devils is low, particularly in the major histocompatibility complex genes of the immune system. The far northwest of Tasmania now holds the last remaining disease-free wild devil populations. The recent discovery of unique major histocompatibility complex genotypes in the northwestern region of Tasmania has raised the possibility that some animals may be resilient to the disease. We examined the differences in the epidemiology and population effects of devil facial tumor disease at 3 well-studied affected sites in eastern Tasmania and 1 in western Tasmania (West Pencil Pine). In contrast to the 3 eastern sites, there has been no rapid increase in disease prevalence or evidence of population decline at West Pencil Pine. Moreover, this is the only onsite at which the population age structure has remained unaltered 4 years after the first detection of disease. The most plausible explanations for the substantial differences in population effects and epidemiology of the disease between eastern and western sites are geographic differences in genotypes or phenotypes of devils and functional differences between tumor strains in the 2 regions. We suggest that conservation efforts focus on identifying whether either or both these explanations are correct and then, if resistance alleles exist, to attempt to spread the resistant alleles into affected populations. Such assisted selection has rarely been attempted for the management of wildlife diseases, but it may be widely applicable.  相似文献   
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4.

Problem

Falls in older persons in developing countries are poorly understood, and falls prevention and health promotion programmes for this population are largely lacking.

Methods

A systematic review was carried out of relevant literature on falls and prevention programmes, and falls prevention education, and a scan undertaken of health promotion programmes for older persons in a representative country - South Africa.

Results

Studies on the risk and prevalence of falls are largely retrospective and hospital-based, with varied methodology, including study period, sampling method and sample size. Falls prevalence is based largely on self-reports in studies on general trauma in all age groups. Falls incidence varies from 10.1% to 54%. No reports could be traced on sustained falls prevention or health promotion programmes.

Conclusion

Scant research has been conducted and little preventive education offered on falls in older persons. Adaptation of the Canadian Falls Prevention Curriculum for developing countries will help to fill gaps in knowledge and practice.

Impact on industry

With rapid increase in the populations of older persons in developing countries, research on age related disorders such as falls is required to guide policy and management of falls.  相似文献   
5.
Warming climatic conditions can pose problems for crop production in many parts of the world, but detailed information on the expression of heat and drought stress resistance genes of potentially affected crop plants is lacking. This information is important to have in order to most efficiently guide the breeding of crops that are adapted to new climatic conditions. A maize (Zea mays) gene microarray, a method used worldwide to evaluate the expression of tens of thousands of genes at once, was used to investigate changes in expression of genes involved in resistance to heat and water stress in milk stage popcorn kernels from undamaged and insect-damaged ears. Popcorn is a form of maize that is more susceptible to heat and drought stress due to its smaller root system. In years of heat and drought stress, expression of many heat shock- and senescence-related proteins increased compared to the year when weather was closer to average conditions, but the expression of many genes related to drought stress resistance decreased in years of weather stress. A different complex of heat shock protein and water stress resistance protein genes had higher expression in kernels from undamaged compared to insect-damaged ears in years of heat and drought stress. These results indicate that the interaction of biotic components, such as insects, are important to consider in developing crop lines with adaptation to stress as this will help identify additional genes and their regulatory components involved in heat and drought stress resistance that might otherwise be overlooked, and will likely be an important strategy for the most effective development of climate stress-tolerant crops globally.  相似文献   
6.
Campana, Pete, John Knox, Andrew Grundstein, and John Dowd, 2012. The 2007‐2009 Drought in Athens, Georgia, United States: A Climatological Analysis and an Assessment of Future Water Availability. Journal of the American Water Resources Association (JAWRA) 48(2): 379‐390. DOI: 10.1111/j.1752‐1688.2011.00619.x Abstract: Population growth and development in many regions of the world increase the demand for water and vulnerability to water shortages. Our research provides a case study of how population growth can augment the severity of a drought. During 2007‐2009, a drought event that caused extreme societal impacts occurred in the Athens, Georgia region (defined as Clarke, Barrow, Oconee, and Jackson counties). An examination of drought indices and precipitation records indicates that conditions were severe, but not worse than during the 1925‐1927, 1954‐1956, and 1985‐1987 drought events. A drought of similar length to the 2007‐2009 drought would be expected to occur approximately every 25 years. Streamflow analysis shows that discharge levels in area streams were at a record low during 2007 before water restrictions were implemented, because of greater water usage caused by recent population increases. These population increases, combined with a lack of water conservation, led to severe water shortages in the Athens region during late 2007. Only after per capita usage decreased did water resources last despite continuing drought conditions through 2009. Retaining mitigation strategies and withdrawal levels such as seen during the height of the drought will be an essential strategy to prevent water shortages during future extreme drought events. The key mitigation strategy, independent local action to restrict water use in advance of state‐level restrictions, is now prohibited by Georgia State Law.  相似文献   
7.
An office containing about 65 employees was found to have 8-h average CO concentrations of 18-26 ppm during a week in winter. On one Friday afternoon, 20 nonsmoking office workers had alveolar CO levels of 23 ± 3 ppm compared to levels of 8 ± 2 ppm in six nonsmoking workers in other offices in the same building. After a weekend at home, the affected office workers displayed reduced alveolar CO levels of 7 ± 2 ppm. The source of the high CO levels was attributed to a parking garage on the same level as the office. Closing fire doors and activating garage fans rectified the situation. The breath sampling method is found to require a correction factor based on the difference between the true alveolar CO and the CO level in the surrounding air. The methods and equipment employed in this study (personal air monitors, electronic data loggers, breath sampling) are recommended for screening and identifying potential CO problems in buildings with similar conditions.  相似文献   
8.
Little is known about the microbial communities carried in wind-eroded sediments from various soil types and land management systems. The novel technique of pyrosequencing promises to expand our understanding of the microbial diversity of soils and eroded sediments because it can sequence 10 to 100 times more DNA fragments than previous techniques, providing enhanced exploration into what microbes are being lost from soil due to wind erosion. Our study evaluated the bacterial diversity of two types of wind-eroded sediments collected from three different organic-rich soils in Michigan using a portable field wind tunnel. The wind-eroded sediments evaluated were a coarse sized fraction with 66% of particles >106 μm (coarse eroded sediment) and a finer eroded sediment with 72% of particles <106 μm. Our findings suggested that (i) bacteria carried in the coarser sediment and fine dust were effective fingerprints of the source soil, although their distribution may vary depending on the soil characteristics because certain bacteria may be more protected in soil surfaces than others; (ii) coarser wind-eroded sediment showed higher bacterial diversity than fine dust in two of the three soils evaluated; and (iii) certain bacteria were more predominant in fine dust (, , and ) than coarse sediment ( and ), revealing different locations and niches of bacteria in soil, which, depending on wind erosion processes, can have important implications on the soil sustainability and functioning. Infrared spectroscopy showed that wind erosion preferentially removes particular kinds of C from the soil that are lost via fine dust. Our study shows that eroded sediments remove the active labile organic soil particulates containing key microorganisms involved in soil biogeochemical processes, which can have a negative impact on the quality and functioning of the source soil.  相似文献   
9.
Mineral dust is an important aerosol species in the Earth’s atmosphere and has a major source within North Africa, of which the Sahara forms the major part. Aerosol Time of Flight Mass Spectrometry (ATOFMS) is first used to determine the mixing state of dust particles collected from the land surface in the Saharan region, showing low abundance of species such as nitrate and sulphate internally mixed with the dust mineral matrix. These data are then compared with the ATOFMS single particle mass spectra of Saharan dust particles detected in the marine atmosphere in the vicinity of the Cape Verde islands, which are further compared with those from particles with longer atmospheric residence sampled at a coastal station at Mace Head, Ireland. Saharan dust particles collected near the Cape Verde Islands showed increased internally mixed nitrate but no sulphate, whilst Saharan dust particles collected on the coast of Ireland showed a very high degree of internally mixed secondary species including nitrate, sulphate and methanesulphonate. This uptake of secondary species will change the pH and hygroscopic properties of the aerosol dust and thus can influence the budgets of other reactive gases, as well as influencing the radiative properties of the particles and the availability of metals for dissolution.  相似文献   
10.
Thyroid hormone levels sufficient for brain development and normal metabolism require a minimal supply of iodine, mainly dietary. Living near the sea may confer advantages for iodine intake. Iodine (I2) gas released from seaweeds may, through respiration, supply a significant fraction of daily iodine requirements. Gaseous iodine released over seaweed beds was measured by a new gas chromatography–mass spectrometry (GC–MS)-based method and iodine intake assessed by measuring urinary iodine (UI) excretion. Urine samples were obtained from female schoolchildren living in coastal seaweed rich and low seaweed abundance and inland areas of Ireland. Median I2 ranged 154–905 pg/L (daytime downwind), with higher values (~1,287 pg/L) on still nights, 1,145–3,132 pg/L (over seaweed). A rough estimate of daily gaseous iodine intake in coastal areas, based upon an arbitrary respiration of 10,000L, ranged from 1 to 20 μg/day. Despite this relatively low potential I2 intake, UI in populations living near a seaweed hotspot were much higher than in lower abundance seaweed coastal or inland areas (158, 71 and 58 μg/L, respectively). Higher values >150 μg/L were observed in 45.6% of (seaweed rich), 3.6% (lower seaweed), 2.3% (inland)) supporting the hypothesis that iodine intake in coastal regions may be dependent on seaweed abundance rather than proximity to the sea. The findings do not exclude the possibility of a significant role for iodine inhalation in influencing iodine status. Despite lacking iodized salt, coastal communities in seaweed-rich areas can maintain an adequate iodine supply. This observation brings new meaning to the expression “Sea air is good for you!”  相似文献   
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