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81.
National surveys and a survey conducted by the authors in March and April 2004 revealed that the public’s concerns about air, water and land pollution have declined during the last four years in the United States and more specifically in the State of New Jersey. In New Jersey pollution remains a major concern of most residents, even during a period of a war, anxiety about terrorism and the economy. Those most anxious about pollution do not believe that government is doing enough to protect the environment, want to maintain current environmental laws, and are worried about the future. Disproportionately they are African and White Americans, middle income, and college graduates, in other words, part of the American mainstream. Direct attempts to weaken environmental protection are likely to be resisted by this core of the population, which does not trust current federal, state and local governments to protect the environment. We expect concerns for the environment to continue and yet change as production processes in the United States continue a trend toward pollution prevention, and we wait for the public’s mental models to catch up with this evolving reality.  相似文献   
82.
Arsenic (As) contamination of the available domestic drinking water from shallow aquifers to villagers in Bangladesh often exceeds the newest WHO standard of <10 µg As L?1 and the older Bangladeshi standard of <50 µg As L?1. An estimated 9.2 million shallow tube wells in Bangladesh deliver water to 97% of the rural population, placing an estimated 57 million people at risk for arsenicosis. The contamination of drinking water by As extends to W. Bengal, India and Nepal. The same shallow aquifers used for domestic water are also used to irrigate food crops, particularly rice. Irrigation adds As to soils and increases exposure of the population to additional As via foods consumed. Selenium (Se), an essential trace mineral found in soils, is absorbed by plants, entering the human food chain. It was suggested that a low dietary intake of Se may be contributing to the problem of human arsenicosis in Bangladesh. Dietary Se acts as a natural antidote to As by (1) accelerating As excretion, (2) sequestering As by complexation and (3) as an antioxidant component of the enzyme glutathione peroxidase that may counteract the prooxidant effects of As that contribute to arsenicosis and cancer. Analysis of 70 agricultural soil samples from Bangladesh by fluorimetry, ICP-AES and Neutron Activation Analysis showed the soils analyzed to be high in As (~33 µg g?1) and biologically low in soluble Se (~0.02 µg g?1). A low dietary intake of Se related to low soil content and this mineral in foods may be contributing to human arsenicosis in the Ganges–Brahmaputra delta.  相似文献   
83.
84.
Irreplaceability is a concept used to describe how close a site is to being essential for achieving conservation targets. Current methods for measuring irreplaceability are based on representative combinations of sites, giving them an extrinsic nature and exponential computational requirements. Surrogate measures based on efficiency (complementarity) are often used as alternatives, but they were never intended for this purpose and do not measure irreplaceability. Current approaches used to estimate irreplaceability have key limitations. Some of these are a result of the tools used, but some are due to the nature of the current definition of irreplaceability. For irreplaceability to be stable and useful for conservation purposes and to resolve limitations, irreplaceability measures should adhere to five axioms; baseline coherence, monotonic responsiveness, proportional responsiveness, intrinsic stability, and bounded outputs. We designed a robust method for measuring a site's proximity to irreplaceability that adheres to these requirements and used it to develop the first systematic global map of irreplaceability based on data for terrestrial vertebrates (n = 29,837 species, >1 million grid cells). At least 3.5% of land surface was highly irreplaceable, and 47.6% of highly irreplaceable cells were contained in 12 countries. More generous thresholds of irreplaceability flag greater portions of land surface that would still be realistic to protect under current global objectives. Irreplaceable sites should form a critical component of any global conservation plan and should be part of the UN Convention on Biological Diversity's post2020 Global Biodiversity Framework strategy, forming part of the 30% protection by 2030 target that is gaining support. The reliable identification of irreplaceable sites will be crucial to halting extinctions.  相似文献   
85.
The importance of abandoned mineral workings to nature conservation is discussed, together with the conflicts posed by proposed new developments. Four ways of preserving, recreating and/or enhancing conservation value are presented and considered. The need for additional research is emphasised.  相似文献   
86.
Analyses for nickel, copper, cobalt and zinc of some leaf, stem and root samples ofHybanthus floribundus from the Eastern Goldfields area of Western Australia is reported. All four metals appear to behave differently. Nickel is taken into the roots, but accumulates in the tops. Copper is largely excluded, but is evenly distributed at low levels. Cobalt is taken up to a greater extent than copper and is evenly distributed. Zinc is accumulated in the roots and is largely excluded from the tops. Plant-soil metal concentrations are discussed. Extraction studies show that nickel in the leaves, and to a lesser extent in woody parts, is associated with pectic carbohydrates. Accumulation and selectivity of uptake are discussed.  相似文献   
87.
Ibrahim Bani  MD PhD 《Disasters》2007,31(S1):S139-S149
This paper uses a public health approach to examine briefly: (a) the progress of universal salt iodisation (USI) in Sudan; (b) the roles of the main actors involved; and (c) the main issues around accelerating USI. The literature, especially that coming from the UN agencies, is analysed and experiences from the recently revitalised USI programme, and related relevant meetings, are distilled. In Sudan the prevalence of goitre is 22 per cent. It is assumed that productivity among the people affected is reduced by 5–25 per cent. Little apparent progress has been made with USI. The Government of Sudan, UN multilateral agencies, international consultative groups, bilateral agencies, global and national non-governmental organisations and, increasingly, the private sector must work together to find innovative approaches to increase awareness of the broader social, public health and nutritional contexts, and to advocate for increased national nd international funding.  相似文献   
88.
The levels of the maternal serum markers alpha-fetoprotein (AFP), human chorionic gonadotrophin (hCG), and unconjugated oestriol (uE3) in 35 pregnant women with early second-trimester oligohydramnios differed from those in a reference population of 1699 singleton pregnancies. Maternal serum AFP levels above the 95th centile of the population distribution were observed in 80 per cent (16/20) of oligohydramnios cases with a normal fetus and in only 20 per cent (3/15) of the cases with a fetus displaying urogenital tract malformations. Elevated levels of hCG (above the 95th centile) and decreased levels of uE3 (below the fifth centile) were encountered in 26 per cent (9/35) and 17 per cent (6/35) of the women, irrespective of the fetal condition. The abnormal profile of the serum markers in early second-trimester oligohydramnios resulted in 57 per cent (20 out of 35) of screen-positive cases for either fetal Down's syndrome or neural tube defects, compared with 8·4 per cent (143 out of 1699) in the reference population.  相似文献   
89.
We report a case in which mosaicism of trisomy 13 was detected in 4/10 cells (40 per cent) in amniotic fluid cell cultures, followed by a low rate of mosaicism (1/160 cells) detected in a fetal blood sample. This finding presents a dilemma both for the genetic counsellor and for the parents in determining whether or not to terminate the pregnancy.  相似文献   
90.
We present a case in which a Greek couple was considered not to be at risk of having children with homozygous β-thalassaemia, an assessment based largely on the father's belief that he carried α-thalassaemia. After their first child was diagnosed with homozygous β-thalassaemia, the case was re-assessed and both parents were shown to have the haematological profile of β-thalassaemia trait. Screening for the common Mediterranean mutations demonstrated that the mother carries the IVS-1 nt 110 G→A β+ -thalassaemia mutation. Direct nucleotide sequencing of PCR-amplified DNA revealed that the father carries a novel β0-thalassaemia mutation, frameshift codons 9/10 (+T). The couple's second pregnancy was terminated after prenatal testing revealed that the fetus had inherited both parental mutations. This case illustrates the need to confirm the carrier status of individuals prior to assessing their genetic risks, and highlights the importance of being able to identify rare or novel β-thalassaemia mutations.  相似文献   
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