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341.
Leonardo Gucciardo Anne Uyttebroek Ivo De Wever Marleen Renard Filip Claus Roland Devlieger Liesbeth Lewi Luc De Catte Jan Deprest 《黑龙江环境通报》2011,31(7):678-688
Sacrococcygeal teratoma (SCT) is one of the most common tumors in newborns with a birth prevalence of up to 1 in 21 700 births. Routine fetal anomaly screening programs allow for prenatal diagnosis in many cases. Fetal ultrasound with Doppler evaluation and more recently magnetic resonance imaging may be used to document the extent of the tumor as well as identifying the population at risk for serious fetal complications. Rapidly growing SCT and highly vascularized tumors are more likely to have hemodynamic repercussions. Fetal hydrops is usually considered as a poor prognostic marker and a potential indicator for fetal intervention. Newborns with SCT require stabilization prior to early surgical resection. In case of malignancy additional chemotherapy may be required. SCT may result in significant morbidity, either directly or as a consequence of surgical therapy. Careful postnatal follow-up is required for timely identification and treatment of complications as well as recurrence. This paper aims to review the perinatal management of this condition. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
342.
Anke Fischer Yitbarek Tibebe Weldesemaet Mikołaj Czajkowski Degu Tadie Nick Hanley 《Conservation biology》2015,29(4):1111-1121
In the face of fundamental land‐use changes, the potential for trophy hunting to contribute to conservation is increasingly recognized. Trophy hunting can, for example, provide economic incentives to protect wildlife populations and their habitat, but empirical studies on these relationships are few and tend to focus on the effects of benefit‐sharing schemes from an ex post perspective. We investigated the conditions under which trophy hunting could facilitate wildlife conservation in Ethiopia ex ante. We used a choice experiment approach to survey international trophy hunters’ (n = 224) preferences for trips to Ethiopia, here operationalized as trade‐offs between different attributes of a hunting package, as expressed through choices with an associated willingness to pay. Participants expressed strong preferences and, consequently, were willing to pay substantial premiums for hunting trips to areas with abundant nontarget wildlife where domestic livestock was absent and for arrangements that offered benefit sharing with local communities. For example, within the range of percentages considered in the survey, respondents were on average willing to pay an additional $3900 for every 10 percentage points of the revenue being given to local communities. By contrast, respondents were less supportive of hunting revenue being retained by governmental bodies: Willingness to pay decreased by $1900 for every 10 percentage points of the revenue given to government. Hunters’ preferences for such attributes of hunting trips differed depending on the degree to which they declared an interest in Ethiopian culture, nature conservation, or believed Ethiopia to be politically unstable. Overall, respondents thus expressly valued the outcomes of nature conservation activities—the presence of wildlife in hunting areas—and they were willing to pay for them. Our findings highlight the usefulness of insights from choice modeling for the design of wildlife management and conservation policies and suggest that trophy hunting in Ethiopia could generate substantially more financial support for conservation and be more in line with conservation objectives than is currently the case. 相似文献
343.
Framing the ecosystem concept through a longitudinal study of developments in science and policy
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Filip Aggestam 《Conservation biology》2015,29(4):1052-1064
This paper examines how scientific literature and policy documents frame the ecosystem concept and how these frames have shaped scientific dialogue and policy making over time. This was achieved by developing a frame typology, as a basis for organizing relevant value expressions, to assess how different frames have altered perspectives of the ecosystem concept. The frame typology and analysis is based on a semi‐grounded and longitudinal document analysis of scientific literature and policy documents using the ecosystem concept. Despite changing discourses and public priorities (e.g., cultural constructs of biodiversity) both science and policy documents are characterized by stable value systems that have not changed substantially since the 1930s. These value systems were defined based on ethical principles that delineate 6 core frames: humans first, dual systems, eco‐science, eco‐holism, animals first, and multicentrism. Specific crises (e.g., climate change) and cross‐disciplinary uptake and re‐uptake of, for example, the ecosystem services concept, have brought new perspectives to the forefront of public discourse. These developments triggered changes in the core frames that, rather than being value based, are based on how the ecosystem is conceptualized under fixed value systems and over time. Fourteen subframes were developed to reflect these longitudinal changes. There are as such clear framing effects in both scientific literature and in policy. Ecosystem research is for instance often characterized by unstated value judgments even though the scientific community does not make these explicit. In contrast, policy documents are characterized by clear value expressions but are principally management driven and human centered. 相似文献
344.
Waste incineration is still an essential technology in the concept of integrated waste management. Most of the combustion residues are incinerator bottom ash. It has been discovered that incinerator bottom ash from the incineration of separated waste in the primary chamber of the modular two-stage incinerator mainly consists of metal oxides, especially SiO2 and CaO, in proportions that are quite similar to those in cement and so the feasibility of its application as a substitute for cement in concrete was investigated. It was found that after 28 days, the flexural and compressive strengths of the binder using bottom ash were practically comparable with those of a pure cement mixture. The results show that it is reasonable to use a binder containing incinerator bottom ash for applications in which an early-stage lower strength of concrete element is acceptable. 相似文献
345.
Katarzyna Wojczulanis-Jakubas Dariusz Jakubas Julien Foucher Joanna Dziarska-Pałac Hubert Dugué 《Die Naturwissenschaften》2013,100(11):1095-1098
Relatively little attention has been paid to sex differences in the migration of birds in autumn. We studied the autumn migration strategy of molecularly sexed males and females in the globally threatened aquatic warbler Acrocephalus paludicola. We captured 176 birds at a stopover site in the Loire estuary at Donges, France. The median date for the passage of adults was 8 days earlier in males than females, although the timing of migration in first-year males and females was similar. This indicates that males, who are without parental duties, can start their migration earlier than females and first-year birds. Adults were significantly heavier than immature birds but did not have higher fat scores. In both age categories, more males (two to three times more) were captured. However, various factors (including tape-luring) can affect observed sex ratio. 相似文献
346.
Małgorzata Pośniak Ewa Kozieł Anna Jeżewska 《International journal of occupational safety and ergonomics》2013,19(3):263-276
Air pollutants emitted while processing phenol-formaldehyde resins have been investigated. Gas chromatography-mass-selective detection was used to separate and identify chemical compounds. It was determined that workers were exposed to formaldehyde in all workplaces. Besides, phenol, acetaldehyde, acrylaldehyde, 2-furaldehyde, xylene, ethylbenzene, toluene, tetrachlorethene, ethyl acetate, butyl acetate were found during the production of frictional materials; and 2-furaldehyde, phenol, naphthalene, 2-furan-methanol, polycyclic aromatic hydrocarbons (PAHs) during the production of abrasive materials. Quantitative analyses were performed with gas chromatogra-phy and high performance liquid chromatography. Assessment of occupational exposure indicated that chemical compounds emitted during the investigated processes might be dangerous for human health, mainly because of suspected carcinogenic compounds: formaldehyde and PAHs. 相似文献
347.
Krystyna Zużewicz Bogusław Biernat Grzegorz Kempa Krzysztof Kwarecki 《International journal of occupational safety and ergonomics》2013,19(3):337-346
AbstractThe objective of the study is to attempt an evaluation of heart rate (HR) and heart rate variability (HRV) regulatory mechanisms in the presence of autonomous nervous system (ANS) components in transient exposure to high altitude hypoxia.During 24 hrs including a stay in hypobaria, the participants had their HR continuously recorded using the Holter method. The following parameters were calculated at rest and during the stay in a thermobarochamber: spectral power in low frequency bands (LF) 0.04-0.15 Hz and high frequency bands (HF) 0.15-0.5 Hz, and the sympathetic-parasympathetic balance index LF/HF.Under hypobaric conditions, a decrease in mean spectral power of R-R intervals was noted within both frequency ranges, compared with the study performed in normobaria. The observed differences were larger at daytime. 相似文献
348.
Zbigniew Witold Engel Maciej Kłaczyński Wiesław Wszołek 《International journal of occupational safety and ergonomics》2013,19(4):367-379
With the present development of digital registration and methods for processing speech it is possible to make effective objective acoustic diagnostics for medical purposes. These methods are useful as all pathologies and diseases of the human vocal tract influence the quality of a patient’s speech signal. Diagnostics of the voice organ can be defined as an unambiguous recognition of the current condition of a specific voice source. Such recognition is based on an evaluation of essential acoustic parameters of the speech signal. This requires creating a vibroacoustic model of selected deformations of Polish speech in relation to specific human larynx diseases. An analysis of speech and parameter mapping in 29-dimensional space is reviewed in this study. Speech parameters were extracted in time, frequency and cepstral (quefrency) domains resulting in diagrams that qualified symptoms and conditions of selected human larynx diseases. The paper presents graphically selected human larynx diseases. 相似文献
349.
Małgorzata Milczarek Andrzej Najmiec 《International journal of occupational safety and ergonomics》2013,19(1):25-33
One of the dimensions treated as part of a company’s safety culture or climate is workers’ attitudes towards risk and safety. In the present study these personal aspects are defined as workers’ safety culture, which is understood as a way of acting focused on life and taking care of one’s health. A questionnaire on safety culture was filled out by 200 employees of a metallurgical enterprise. Factor analysis was used to determine empirical scales of the questionnaire, whereas variance analysis was used to test hypotheses. The results confirmed the hypotheses that people who experienced accidents, dangerous situations, and—to a lesser extent—health problems had a lower level of safety culture. Nevertheless not all of the scales determined during factor analysis turned out to be significant as far as all kinds of those undesirable situations are concerned. Proposals for future studies are formulated in the conclusion. 相似文献
350.
Zofia Pawłowska 《International journal of occupational safety and ergonomics》2013,19(3):284-290
Improvement of occupational safety and health (OSH) management is closely related to the development of OSH performance measurement, which should include OSH outcomes (e.g., occupational accidents), OSH inputs (including working conditions) and OSH-related activities. The indicators used to measure the OSH outcomes are often called lagging indicators, and the indicators of inputs and OSH activities are leading indicators. A study was conducted in 60 companies in order to determine what kinds of indicators were used for OSH performance measurement by companies with different levels of OSH performance. The results reveal that the indicators most commonly used in all of the companies are those related to ensuring compliance with the statutory requirements. At the same time, the leading indicators are much more often adopted in companies with a higher performance level. These companies also much more often monitor on a regular basis the indicators adopted for the evaluation of their OSH performance. 相似文献