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81.
There is a significant relationship between ambient temperature and mortality. In healthy individuals with no underlying co-morbid conditions, there is an efficient heat regulation system which enables the body to effectively handle thermal stress. However, in vulnerable groups, especially in elderly over the age of 65 years, infants and individuals with co-morbid cardiovascular and/or respiratory conditions, there is a deficiency in thermoregulation. When temperatures exceed a certain limit, being cold winter spells or heat waves, there is an increase in the number of deaths. In particular, it has been shown that at temperatures above 27 °C, the daily mortality rate increases more rapidly per degree rise compared to when it drops below 27 °C.This is especially of relevance with the current emergency of global warming. Besides the direct effect of temperature rises on human health, global warming will have a negative impact on primary producers and livestock, leading to malnutrition, which will in turn lead to a myriad of health related issues. This is further exacerbated by environmental pollution.Public health measures that countries should follow should include not only health-related information strategies aiming to reduce the exposure to heat for vulnerable individuals and the community, but improved urban planning and reduction in energy consumption, among many others. This will reduce the carbon footprint and help avert global warming, thus reducing mortality. 相似文献
82.
Boswellia papyrifera (Del) Hochst is a key dry land plant species in the Horn of Africa with high socio-economic significance in Ethiopia, Eritrea and Sudan. In recent decades, populations of this species are declining due to lack of recruitment through natural regeneration. This study investigated the potential of vegetative propagation using leafless branch cuttings as an alternative means of reproduction for the species. The effect of time of collection and cutting sizes (length and thickness) on shooting and rooting of the cuttings was investigated. The effects of these three factors were analysed, two-by-two, in three separate factorial experiments each arranged in a randomized complete block design. Time of collection affected cutting performance: shooting percent, shoot number, cutting vigour, leaf number, leaf length, rooting percent and root length were best when cuttings were collected in February-March, and weakest in May. Medium to long cuttings (1.0 m-2.0 m) and thicker cuttings (0.19-0.27 m) performed better than shorter or thinner cuttings. These results indicate that B. papyrifera is amenable to macro-propagation via leafless branch cuttings. Reproduction of B. papyrifera through macro-propagation may help overcome the population recruitment bottleneck of this important species and will help the long-term yield possibilities of its precious product frankincense. 相似文献
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An online systematic error correction is presented and examined as a technique to improve the accuracy of real-time numerical weather prediction, based on the dataset of model errors(MEs) in past intervals. Given the analyses, the ME in each interval(6 h) between two analyses can be iteratively obtained by introducing an unknown tendency term into the prediction equation, shown in Part I of this two-paper series. In this part, after analyzing the 5-year(2001–2005) GRAPESGFS(Global Forecast System of the Global and Regional Assimilation and Prediction System) error patterns and evolution,a systematic model error correction is given based on the least-squares approach by firstly using the past MEs. To test the correction, we applied the approach in GRAPES-GFS for July 2009 and January 2010. The datasets associated with the initial condition and SST used in this study were based on NCEP(National Centers for Environmental Prediction) FNL(final) data.The results indicated that the Northern Hemispheric systematically underestimated equator-to-pole geopotential gradient and westerly wind of GRAPES-GFS were largely enhanced, and the biases of temperature and wind in the tropics were strongly reduced. Therefore, the correction results in a more skillful forecast with lower mean bias and root-mean-square error and higher anomaly correlation coefficient. 相似文献
86.
Kenneth F. Rijsdijk Julian P. Hume Frans Bunnik F.B. Vincent Florens Claudia Baider Beth Shapiro Johannes van der Plicht Anwar Janoo Owen Griffiths Lars W. van den Hoek Ostende Holger Cremer Tamara Vernimmen Perry G.B. De Louw Assenjee Bholah Salem Saumtally Nicolas Porch James Haile Mike Buckley Matthew Collins Edmund Gittenberger 《Quaternary Science Reviews》2009,28(1-2):14-24
Although the recent history of human colonisation and impact on Mauritius is well documented, virtually no records of the pre-human native ecosystem exist, making it difficult to assess the magnitude of the changes brought about by human settlement. Here, we describe a 4000-year-old fossil bed at Mare aux Songes (MAS) in south-eastern Mauritius that contains both macrofossils (vertebrate fauna, gastropods, insects and flora) and microfossils (diatoms, pollen, spores and phytoliths). With >250 bone fragments/m2 and comprising 50% of all known extinct and extant vertebrate species (ns = 44) of Mauritius, MAS may constitute the first Holocene vertebrate bone Concentration-Lagerstätte identified on an oceanic volcanic island. Fossil remains are dominated by extinct giant tortoises Cylindraspis spp. (63%), passerines (~10%), small bats (7.8%) and dodo Raphus cucullatus (7.1%). Twelve radiocarbon ages [four of them duplicates] from bones and other material suggest that accumulation of fossils took place within several centuries. An exceptional combination of abiotic conditions led to preservation of bones, bone collagen, plant tissue and microfossils. Although bone collagen is well preserved, DNA from dodo and other Mauritian vertebrates has proved difficult. Our analysis suggests that from ca 4000 years ago (4 ka), rising sea levels created a freshwater lake at MAS, generating an oasis in an otherwise dry environment which attracted a diverse vertebrate fauna. Subsequent aridification in the south-west Indian Ocean region may have increased carcass accumulation during droughts, contributing to the exceptionally high fossil concentration. The abundance of floral and faunal remains in this Lagerstätte offers a unique opportunity to reconstruct a pre-human ecosystem on an oceanic island, providing a key foundation for assessing the vulnerability of island ecosystems to human impact. 相似文献
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89.
Fecundity estimates were made from 72 smooth oreo (Pseudocyttus maculatus Gilchrist, 1906) and 77 black oreo (Allocyttus niger James, Inada & Nakamura, 1988) with oocytes in late vitellogenesis, captured from the south Chatham Rise during November 1986. Absolute fecundities ranged from 6000 to 84 000 for smooth oreo and 5000 to 62 000 for black oreo, with relative fecundities of 10 800 and 17 500 eggs per kg body weight for smooth and black oreos, respectively. Both species have absolute and relative fecundities within the same order of magnitude as orange roughy, but one to two orders of magnitude lower than six other commercially exploited fish species from the New Zealand continental shelf or slope region. The comparatively low fecundity of the oreo species could contribute to susceptibility to overfishing. 相似文献
90.
There is a significant relationship between ambient temperature and mortality. In healthy individuals with no underlying co-morbid conditions, there is an efficient heat regulation system which enables the body to effectively handle thermal stress. However, in vulnerable groups, especially in elderly over the age of 65 years, infants and individuals with co-morbid cardiovascular and/or respiratory conditions, there is a deficiency in thermoregulation. When temperatures exceed a certain limit, being cold winter spells or heat waves, there is an increase in the number of deaths. In particular, it has been shown that at temperatures above 27 °C, the daily mortality rate increases more rapidly per degree rise compared to when it drops below 27 °C.This is especially of relevance with the current emergency of global warming. Besides the direct effect of temperature rises on human health, global warming will have a negative impact on primary producers and livestock, leading to malnutrition, which will in turn lead to a myriad of health related issues. This is further exacerbated by environmental pollution.Public health measures that countries should follow should include not only health-related information strategies aiming to reduce the exposure to heat for vulnerable individuals and the community, but improved urban planning and reduction in energy consumption, among many others. This will reduce the carbon footprint and help avert global warming, thus reducing mortality. 相似文献