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121.
Ammonia volatilization from the mineralization of uric acid and urea has a major impact on the poultry industry and the environment. Dry acids are commonly used to reduce ammonia emissions from poultry houses; however, little is known about how acidification affects the litter biologically. The goal of this laboratory incubation was to compare the microbiological and physiochemical effects of dry acid amendments (Al+Clear, Poultry Litter Treatment, Poultry Guard) on poultry litter to an untreated control litter and to specifically correlate uric acid and urea contents of these litters to the microbes responsible for their mineralization. Although all three acidifiers eventually produced similar effects within the litter, there was at least a 2-wk delay in the microbiological responses using Poultry Litter Treatment. Acidification of the poultry litter resulted in >3 log increases in total fungal concentrations, with both uricolytic (uric acid degrading) and ureolytic (urea degrading) fungi increasing by >2 logs within the first 2 to 4 wk of the incubation. Conversely, total, uricolytic, and ureolytic bacterial populations all significantly declined during this same time period. While uric acid and urea mineralization occurred within the first 2 wk in the untreated control litter, acidification resulted in delayed mineralization events for both uric acid and urea (2 and 4 wk delay, respectively) once fungal cell concentrations exceeded a threshold level. Therefore, fungi, and especially uricolytic fungi, appear to have a vital role in the mineralization of organic N in low-pH, high-N environments, and the activity of these fungi should be considered in best management practices to reduce ammonia volatilization from acidified poultry litter.  相似文献   
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Conservation technology holds the potential to vastly increase conservationists’ ability to understand and address critical environmental challenges, but systemic constraints appear to hamper its development and adoption. Understanding of these constraints and opportunities for advancement remains limited. We conducted a global online survey of 248 conservation technology users and developers to identify perceptions of existing tools’ current performance and potential impact, user and developer constraints, and key opportunities for growth. We also conducted focus groups with 45 leading experts to triangulate findings. The technologies with the highest perceived potential were machine learning and computer vision, eDNA and genomics, and networked sensors. A total of 95%, 94%, and 92% respondents, respectively, rated them as very helpful or game changers. The most pressing challenges affecting the field as a whole were competition for limited funding, duplication of efforts, and inadequate capacity building. A total of 76%, 67%, and 55% respondents, respectively, identified these as primary concerns. The key opportunities for growth identified in focus groups were increasing collaboration and information sharing, improving the interoperability of tools, and enhancing capacity for data analyses at scale. Some constraints appeared to disproportionately affect marginalized groups. Respondents in countries with developing economies were more likely to report being constrained by upfront costs, maintenance costs, and development funding (p = 0.048, odds ratio [OR] = 2.78; p = 0.005, OR = 4.23; p = 0.024, OR = 4.26), and female respondents were more likely to report being constrained by development funding and perceived technical skills (p = 0.027, OR = 3.98; p = 0.048, OR = 2.33). To our knowledge, this is the first attempt to formally capture the perspectives and needs of the global conservation technology community, providing foundational data that can serve as a benchmark to measure progress. We see tremendous potential for this community to further the vision they define, in which collaboration trumps competition; solutions are open, accessible, and interoperable; and user-friendly processing tools empower the rapid translation of data into conservation action. Article impact statement: Addressing financing, coordination, and capacity-building constraints is critical to the development and adoption of conservation technology.  相似文献   
125.
New systems approaches by the U.S. Environmental Protection Agency (EPA) have attempted to prevent and limit environmental damages through multimedia management of resources, energy, and environmental impacts, while engaging communities, environmental groups, facilities, industries, states, and local agencies. Collectively these diverse interests have begun to partner with corporate management to work toward a shared vision of how multimedia management and multistakeholder participation can best evolve in concert with environmental management system approaches. This article analyzes one industry-specific program under the Common Sense Initiative, called an Alternative System of Environmental Protection (ASEP) for the Computers and Electronics Subcommittee. The significance of this working group's attempt to increase regulatory flexibility lies in its collective establishment of an alternative regulatory framework for an entire industry. Contrary to many other EPA single-facility pilot programs, this method cuts across the entire computer and electronics industry. The group hopes to achieve sector-wide regulatory improvements through a process providing funding for shared research, dynamic feedback, and technical assistance, while engaging in multistakeholder relationships with communities, workers, local governmental agencies, and other stakeholders.  相似文献   
126.
Forty percent of pregnant women aged 37 years and over do not have prenatal diagnosis despite being eligible for a free test. The present study aimed to determine how often, and which, untested women were making a choice about this, how many declined an offer and why. A questionnaire was given to untested women, aged 37 years and over, at no less than 24 weeks gestation. A total of 375 (81.5%) women declined, 72 (16%) were not offered a test and 13 presented too late antenatally. There was a three-fold increased likelihood (OR 3.10 95% CI 1.44, 6.65) of no offer for urban non-English speaking background women, compared with the reference group (metropolitan, English speaking). Unpartnered women were also significantly less likely to receive an offer (OR 3.18, 95% CI 1.19, 8.46). Risk to the baby was the main reason for declining. When offered non-invasive prenatal screening, most decliners of prenatal diagnosis accepted, even those who declined because they were opposed to abortion. We estimate that overall 33% of older pregnant women were being offered and declining amniocentesis and/or chorion villus sampling (CVS). Only 6% were not offered a test, but this small proportion is over-represented by minority groups who must be given equal opportunity to make this choice. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
127.
A case of prenatally diagnosed non-mosaic trisomy 20 in cells cultured from a chorionic villus sample (CVS)is presented. The term placental karyotype was also non-mosaic trisomy 20. The karyotype of thenewborn was 46,XY/47,XY,+20 in foreskin cultures and in a second skin culture; blood lymphocyte culture was 46,XY. Aside from diffuse, hypopigmentary swirls along the lines of Blaschko observed on hisextremities and trunk, referred to as hypomelanosis of Ito, the patient is clinically normal at 8¾ years ofage. In addition, he is one of the oldest reported cases of mosaic trisomy 20 confirmed after birth forwhich the clinical outcome has been monitored. This case demonstrates that these trisomy 20 findings are compatible with normal psychomotor development and phenotype. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
128.
The Sandia National Laboratories Environmental Restoration Project is in the process of determining the nature and extent of environmental contamination at numerous potential release sites. Sites found to be contaminated above certain action levels must be remediated. Sandia is responsible for preparing preliminary cost estimates for remediation activities in order to meet Department of Energy planning requirements for future funding. Sandia used the ENVEST parametric cost-estimating model to prepare conceptual cost estimates for remediation prior to having definitive knowledge of the nature and extent of contamination. This article describes the estimating approach and the results achieved at Sandia.  相似文献   
129.
Summary This paper is based on a research study to evaluate the feasibility of reclaiming low-lying swamplands by filling them with refuse, rather than with dirt, sand or other inert materials. A supplementary study was also initiated to prepare a preliminary evaluation of disposing of solid waste from the Bangkok Metropolis region. This included a preliminary assessment of available filling areas and of costs for filling them, together with projected values of reclaimed land. The latter study was included to determine if a feasibility study for utilising refuse landfilling for Bangkok solid-waste disposal is warranted, and to prepare the feasibility study terms of reference if so justified. Results of the literature review, practices of refuse landfilling in swamps, and methods and materials employed in conduct of the study are described. This is followed by evaluations of the feasibility of disposing solid wastes utilising swamplands, an environmental analysis of the same, and the conclusions of the study.The authors are Consulting Engineers at Seatec International, Bangkok. The views in this paper are those of the authors and do not necessarily reflect World Bank policies.  相似文献   
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