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141.
Amanda S. Hering Cynthia L. Bell Marc G. Genton 《Environmental and Ecological Statistics》2009,16(2):225-250
We analyze and model the structure of spatio-temporal wildfire ignitions in the St. Johns River Water Management District
in northeastern Florida. Previous studies, based on the K-function and an assumption of homogeneity, have shown that wildfire events occur in clusters. We revisit this analysis based
on an inhomogeneous K-function and argue that clustering is less important than initially thought. We also use K-cross functions to study multitype point patterns, both under homogeneity and inhomogeneity assumptions, and reach similar
conclusions as above regarding the amount of clustering. Of particular interest is our finding that prescribed burns seem
not to reduce significantly the occurrence of wildfires in the current or subsequent year over this large geographical region.
Finally, we describe various point pattern models for the location of wildfires and investigate their adequacy by means of
recent residual diagnostics.
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Marc G. Genton (Corresponding author)Email: Email: |
142.
Despite significant interest in the attributions employees make about their organization's human resource (HR) practices, there is little understanding of the antecedents of HR attributions. Drawing on attribution theory, we suggest that HR attributions are influenced by information (perceptions of distributive and procedural fairness), beliefs (organizational cynicism), and motivation (perceived relevance). We test a model through a two‐wave survey of 347 academic faculty in the United Kingdom, examining their attributions of the purpose of their institution's workload management framework. After two preliminary studies (an interview study and a cross‐sectional survey) to establish contextually relevant attributions, we find that fairness and cynicism are important for the formation of internal attributions of commitment but less so for cost‐saving or exploitation attributions. Fairness and cynicism also interact such that distributive fairness buffers the negative attributional effect of cynicism, and individuals are more likely to attribute fair procedures to external forces if they are cynical about their organization. This study furthers the application of attribution theory to the organizational domain while making significant contributions to our understanding of the HR‐performance process. 相似文献
143.
AbstractObjective: Focusing on children (0–17?years), this study aimed to investigate injury and accident characteristics for bicyclists and to evaluate the use and protective effect of bicycle helmets.Method: This nationwide Swedish study included children who had visited an emergency care center due to injuries from a bicycle crash. In order to investigate the causes of bicycle crashes, data from 2014 to 2016 were analyzed thoroughly (n?=?7967). The causes of the crashes were analyzed and categorized, focusing on 3 subgroups: children 0–6, 7–12, and 13–17?years of age. To assess helmet effectiveness, the induced exposure approach was applied using data from 2006 to 2016 (n?=?24,623). In order to control for crash severity, only bicyclists who had sustained at least one Abbreviated Injury Scale (AIS) 2+ injury (moderate injury or more severe) in body regions other than the head were included.Results: In 82% of the cases the children were injured in a single-bicycle crash, and the proportion decreased with age (0–6: 91%, 7–12: 84%, 13–17: 77%). Of AIS 2+ injuries, 8% were head injuries and 85% were injuries to the extremities (73% upper extremities and 13% lower extremities). Helmet use was relatively high up to the age of 10 (90%), after which it dropped. Helmets were much less frequently used by teenagers (14%), especially girls. Consistently, the share of head injuries increased as the children got older. Bicycle helmets were found to reduce all head injuries by 61% (95% confidence interval [CI], 10: +/? 10%) and AIS 2+ head injuries by 68% (95% CI, 12: +/? 12%). The effectiveness in reducing face injuries was lower (45% CI +/? 10% for all injuries and 54% CI +/? 32% for AIS2+ injuries).Conclusions: This study indicated that bicycle helmets effectively reduce injuries to the head and face. The results thus point to the need for actions aimed at increasing helmet use, especially among teenagers. Protective measures are necessary to further reduce injuries, especially to the upper extremities. 相似文献
144.
Turner syndrome (TS), a common chromosomal abnormality affecting females, is associated with partial or complete loss of the second sex chromosome. Although the classic karyotype is 45, X, the detection of mosaic TS is increasing. TS is a multi-system disorder with significant endocrine, cardiovascular and reproductive impacts. Accelerated ovarian follicular loss leads to primary amenorrhoea or premature ovarian insufficiency and infertility. Early diagnosis and counselling regarding hormone replacement therapy and future reproductive capacity, including fertility preservation, are essential to improve reproductive outcomes. Pubertal induction or estrogen replacement is usually required to optimise long-term health outcomes; however, initiation may be delayed due to delayed diagnosis. Spontaneous pregnancy occurs in a small number of women; however, many require donor oocytes and assisted reproductive technology to achieve a pregnancy. Pregnancy is a high risk especially when associated with congenital heart disease. Prepregnancy counselling by the multidisciplinary team (MDT) to identify contraindications and optimise pre-existing health issues is essential. Pregnancy management should be led by a maternal-fetal medicine unit with input from the MDT. This review examines reproductive health outcomes in women with TS and how best to manage them to reduce health risks and improve maternal and neonatal outcomes. 相似文献
145.
Livens FR Jones MJ Hynes AJ Charnock JM Mosselmans JF Hennig C Steele H Collison D Vaughan DJ Pattrick RA Reed WA Moyes LN 《Journal of environmental radioactivity》2004,74(1-3):211-219
Technetium, uranium and neptunium may all occur in the environment in more than one oxidation state (IV or VII, IV or VI and IV or V respectively). The surface of mackinawite, the first-formed iron sulfide phase in anoxic conditions, can promote redox changes so a series of laboratory experiments were carried out to explore the interactions of Tc, U and Np with this mineral. The products of reaction were characterised using X-ray absorption spectroscopy. Technetium, added as TcO4(-), is reduced to oxidation state IV and forms a TcS(2)-like species. On oxidation of the mackinawite in air to form goethite, Tc remains in oxidation state IV but in an oxide, rather than a sulfide environment. At low concentrations, uranium forms uranyl surface complexes on oxidised regions of the mackinawite surface but at higher concentrations, the uranium promotes surface oxidation and forms a mixed oxidation state oxide phase. Neptunium is reduced to oxidation IV and forms a surface complex with surface sulfide ions. The remainder of the Np coordination sphere is filled with water molecules or hydroxide ions. 相似文献
146.
Croft WA Jastromski BM Croft AL Peters HA 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(3):301-320
The investigations of four Cases involving mold-contaminated buildings and human reaction to exposure, documents tests of extracted urine containing trichothecene mycotoxins confirming exposure and the diagnosis of mycotoxicosis in humans. In each of four Cases, the urine demonstrated antibiotic activity, sulfuric acid charring, and protein release. Urine was extracted using ethyl acetate 40V/60V[EA]. Extracted mycotoxin spotted on (TLC) displayed color and a range of (rf) between 0.2-0.6 using various solvents. Extract was re-suspended using 50% ethanol V/V to inject mycotoxins into weanling female Sprague-Dawley rats. Degeneration and necrosis of the rat's tissue followed. Koch's Postulates conditions were fulfilled by isolation of the causative agent, the trichothecene mycotoxins and the reproduction of disease. Examination of human tissue within the urine extraction group confirms Koch's Postulates and comparative pathology confirms inhalation Mycotoxicosis, with severe necrosis of the central nervous system and severe scarring within the lungs. Extraction of mycotoxins from human patient urine is a very useful confirmatory test to demonstrate exposure and identify mycotoxicosis. Low concentrations (6%) of sodium hypochlorite were ineffective against the activity of trichothecene mycotoxin. The severity or stages of disease directly correlates the level of exposure or poisoning (Patent Pending). 相似文献
147.
148.
With mounting research showing the many benefits of having women involved in community-based conservation (CBC) efforts, we wanted to identify and measure the attitudes and barriers to women participating in a CBC program in western Belize. We surveyed 500 women in communities surrounding the Vaca Forest Reserve to measure their interest in, attitudes toward, and possible barriers to participating in a CBC program. We assessed women’s intent to participate in CBC activities using the Theory of Planned Behavior to identify the attitudinal, normative, and behavioral control constructs that best predict their intentions to participate. Women indicated positive attitudes toward participating in a CBC program, while perceived behavioral controls had the largest influence on their intent to participate. Understanding the importance of and influence of these constructs on women’s participation will help us and other conservation scientists work with women to collaboratively design effective conservation programs. 相似文献
149.
150.
We surveyed three distinct samples of employees (Ns of 238, 102, and 981) in order to examine relations among various types of underemployment, job satisfaction, organizational commitment, and turnover intentions. Each dimension of underemployment is explored as a case of poor person‐job fit, and the fit literature is used to produce hypotheses about these relations. We also developed and validated the 9‐item Scale of Perceived Overqualification (SPOQ) to tap employee perceptions of surplus education, experience, and KSAs (knowledge, skills, and abilities). In general, perceptions of underemployment were associated with poor job satisfaction, particularly for facets with a direct causal relationship with the specific dimension of underemployment, such as overqualification and satisfaction with work. Perceived overqualification was also related to lower affective commitment, and higher intentions to turnover. For part‐time work, negative attitudes were only found when employees expressed a preference for full‐time work; a similar trend was not found for temporary workers, however. Implications for theory, research, and practice are delineated. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献