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51.
Phosphorus (P) is an essential macronutrient in agriculture; however, lack of reporting makes its supply chain a black box. By using literature synthesis on the P challenge, we identify four areas where the reporting process is problematic: P reserves and resources; P losses along the supply chain; P externalities; and access to data. We find that in these areas, the reporting system is inconsistent, inaccurate, incomplete, fragmented and non-transparent. We use systems analysis to discuss implications of reporting on the sustainability of the P supply chain. We find that reporting is essential for the achievement of global P governance and the human right to adequate food. It can also inform decision makers and other impacted stakeholders on policies on agriculture, food security, pollution and international conflict. An improved P reporting process also allows a better evaluation of global sustainability commitments such as the United Nations Sustainable Development Goals.  相似文献   
52.
Pet allergens and mold growth related to damp are common phenomena in day care centers in Sweden but exposure measurements of these factors are lacking. The aim of this study was to investigate the relationship between building construction and indoor environment quality in Swedish day care centers and the potential for exposure to fungi (analyzed by quantitative PCR) and animal allergens (analyzed by ELISA). Measurements were performed in 21 day care centers (103 rooms) from one municipality in Sweden, which were identified as constructions at risk of dampness (85% of the buildings) and with visible damage and mold growth (54% of the buildings). Dust samples were collected using cotton swab and Petri dishes. Total fungal DNA was detected in 99% and 100%, Aspergillus/Penicillium DNA in 54% and 68%, and Stachybotrys chartarum DNA in 4% and 9% of the investigated rooms in cotton swab and Petri dish samples, respectively. The total fungal DNA levels (Geometric Mean, GM) were 4.2 × 10(6) cell equivalents per m(2) and 2.9 × 10(5) cell equivalents per m(2) per day in the swab and Petri dish samples, respectively. The concentrations (GM) of cat (Fel d1), dog (Can f1), and horse (Equ cx) allergens were 9.4, 7.2 ng m(-2) day(-1), and 5.0 unit per m(2) per day, respectively. Total fungal DNA levels were higher in risk construction buildings (p = 0.01), in rooms with linoleum flooring material (p = 0.003), and in buildings with rotating heat exchangers (p = 0.02). There were associations between total fungal DNA levels and cat (p = 0.02), dog (p < 0.001), and horse (p = 0.001) allergens. In conclusion, risk constructions, damp constructions, mould growth, fungal DNA, and animal allergens were common exposure factors in Swedish day care centers. Building constructions that represent a high risk for internal dampness should be avoided in the future, and measures to reduce allergen levels should be considered to protect pet-allergic children from asthmatic problems.  相似文献   
53.
An animal can only survive in a given habitat if it has enough time to find, process and digest food whilst avoiding predation. The time it has for food acquisition is affected by the vegetation and competition with conspecifics, which depends on aggregation tendencies. We used the relationships between time allocations, on the one hand, and climatic variables (as a proxy for habitat quality) and group size, on the other, to develop a model that predicts maximum ecologically tolerable group size at different locations for spider monkeys. Spider monkeys are particularly interesting because the social communities often split up into small units. Temperature variation and rainfall variation were the main determinants of time budgets. Community size and average annual rainfall determined party size. The model correctly predicted presence or absence of spider monkeys at 78–83% of 217 New World forest sites. Within the geographical range of the species, this time budget model predicted the presence of spider monkeys better than a model based directly on climate variables. Predicted community and party sizes were significantly larger at sites where spider monkeys are present than at sites where they are absent. As required by the model, predicted maximum community sizes were significantly larger than observed community sizes. Moving time showed a U-shaped relationship with party size, which suggests that moving time is the factor that keeps spider monkey communities from travelling together in a tight group.  相似文献   
54.
In November 1990, the Silicate Technology Corporation's (STC) proprietary process for treating soil contaminated with toxic semivolatile organic and inorganic contaminants was evaluated in a Superfund Innovative Technology Evaluation (SITE) field demonstration at the Selma Pressure Treating (SPT) wood preserving site in Selma, California. The SPT site was contaminated principally with pentachlorophenol (PCP) and arsenic, as well as lesser amounts of chromium and copper. Because of their importance when selecting a remedy for the site, PCP and arsenic were identified as critical analytes to evaluate the effectiveness of treatment.

Evaluation of STC's treatment process was based on contaminant mobility, measured by numerous leaching tests, and structural integrity of the solidified material, measured by physical, engineering, and morphological tests. An economic analysis was also performed, using cost information supplied by STC and supplemented by information generated during the demonstration.

Conclusions drawn from this SITE demonstration evaluation are: (1) the STC process can chemically stabilize contaminated soils similar to those at the Selma site that contain both semivolatile organic and inorganic contaminants; (2) PCP was successfully treated as demonstrated by total waste analysis; (3) heavy metals such as arsenic can be immobilized successfully based on various leach-test criteria; (4) the short-term physical stability of the treated waste was good, with unconfined compressive strengths (UCS) well above landfill solidification standards; (5) treatment resulted in a volume increase of 59 to 75 percent (68 percent average) and a slight increase in bulk density; and (6) the process is expected to cost approximately $190 to $360 per cubic yard when it is used to treat 15,000 cubic yards of waste similar to that found at the STC demonstration site, assuming that on-site, in-place disposal is performed.  相似文献   
55.
Our experiences calculating a local ecological footprint of Oslo form the basis for a discussion of key methodological aspects supporting the use of local sustainability indicators. The footprint's strength is its ability to communicate simply the complexity of global environmental challenges. Initially developed for measuring per capita consumption at the national level, the footprint has been adopted at local and regional levels. We argue for adjustments in the footprint methodology when shifting from a national to a local policy context, to ensure the indicator's applicability in local politics and administration. First, the analysis should be limited to consumption aspects relevant to the local environmental policy agenda. Second, the analysis should integrate as much genuine local data as possible. We argue also that a standardised methodology based on the national footprint approach, with the main purpose of international benchmarking of cities, cannot but reduce the indicator's usefulness for administrative/political guidance, due to the methodology's lack of transparency and inability to identify local variations.  相似文献   
56.
A healthy female with a brother suffering from Lesch–Nyhan syndrome was assigned a carrier status on the basis of haplotype analysis employing flanking and intragenic polymorphic markers of the HPRT gene. Her mother has been confirmed as a definite carrier by cell growth selection studies in cultured fibroblasts. In our proposita's first pregnancy, a male fetus was identified carrying the risk allele. Afterwards, the underlying novel mutation A161E (GCA→GAA at position c482) could be identified in the affected brother and in the heterozygous mother but not in the DNA of the pregnant sister and fetus. The fetus was also confirmed to be normal by uptake of 14C-hypoxanthine in cultured amniotic cells. To test the discrepancy, the investigation was extended by recruiting additional family members. The data obtained showed that the mother had passed her risk haplotype to the affected son as well as to her mutation-carrying and non–mutation-carrying daughters. This provides the first evidence of concomitant somatic and germline mosaicism in Lesch–Nyhan syndrome. The study has a bearing on genetic counselling and cautions against the reliability of only using indirect genetic diagnosis even with intragenic markers. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
57.
58.
An important question with respect to the Macondo blowout is whether the accident is a symptom of systemic safety problems in the deepwater drilling industry. An answer to such a question is hard to obtain unless the risk level of the oil and gas (O&G) industry is monitored and evaluated over time. This article presents information and indicators from the Risk Level Project (RNNP) in the Norwegian O&G industry related to safety climate, barriers and undesired incidents, and discusses the relevance for deepwater drilling. The main focus of the major hazard indicators in RNNP is on production installations, whereas only a limited number of incident indicators and barrier indicators are related to mobile drilling units. The number of kicks is an important indicator for the whole drilling industry, because it is an incident with the potential to cause a blowout. Currently, the development and monitoring of safety indicators in the O&G industry seems to be limited to a short list of “accepted” indicators, but there is a need for more extensive monitoring and understanding. This article suggests areas of extensions of the indicators in RNNP for drilling based on experience from the Macondo blowout. The areas are related to schedule and cost, well planning, operational aspects, well incidents, operators’ well response, operational aspects and status of safety critical equipment. Indicators are suggested for some of the areas. For other areas, more research is needed to identify the indicators and their relevance and validity.  相似文献   
59.
Climate change is a multi-dimensional issue and in terms of adaptation numerous state and non-state actors are involved from global to national and local scales. The aim of this paper is first to analyse specific institutional networks involved in climate change predominantly at the national level in South Africa and second to determine how different stakeholders perceive their role vis-a-vis climate change adaptation. Within the South African context there is a gap in understanding and evaluating how institutional networks operate and thus the findings of this work may help inform and strengthen such relationships in the future. Results showed that few institutions fully understand the implications of adaptation and their roles and responsibilities have not yet been properly defined. Constraints relating to capacity, lack of awareness and poor information flow need to be addressed. Climate change is perceived as an important issue although problems such as poverty reduction and job creation remain national priorities. Most importantly this research has demonstrated how adaptation challenges the hierarchical manner in which government works and a more collaborative approach to climate change adaptation is needed. Adaptation needs to be mainstreamed and institutional networks need to be strengthened in order for adaptation mechanisms to be effectively implemented.
Ingrid Christine KochEmail:
  相似文献   
60.

Objective

We performed a 1-year evaluation of a novel strategy of simultaneously analyzing single nucleotide variants (SNVs), copy number variants (CNVs) and copy-number-neutral Absence-of-Heterozygosity from Whole Exome Sequencing (WES) data for prenatal diagnosis of fetuses with ultrasound (US) anomalies and a non-causative QF-PCR result.

Methods

After invasive diagnostics, whole exome parent-offspring trio-sequencing with exome-wide CNV analysis was performed in pregnancies with fetal US anomalies and a non-causative QF-PCR result (WES-CNV). On request, additional SNV-analysis, restricted to (the) requested gene panel(s) only (with the option of whole exome SNV-analysis afterward) was performed simultaneously (WES-CNV/SNV) or as rapid SNV-re-analysis, following a normal CNV analysis.

Results

In total, 415 prenatal samples were included. Following a non-causative QF-PCR result, WES-CNV analysis was initially requested for 74.3% of the chorionic villus (CV) samples and 45% of the amniotic fluid (AF) samples. In case WES-CNV analysis did not reveal a causative aberration, SNV-re-analysis was requested in 41.7% of the CV samples and 17.5% of the AF samples. All initial analyses could be finished within 2 weeks after sampling. For SNV-re-analysis during pregnancy, turn-around-times (TATs) varied between one and 8 days.

Conclusion

We show a highly efficient all-in-one WES-based strategy, with short TATs, and the option of rapid SNV-re-analysis after a normal CNV result.  相似文献   
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