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61.
Denys Yemshanov Frank H. Koch Daniel W. McKenney Marla C. Downing Frank Sapio 《Risk analysis》2009,29(6):868-884
Nonindigenous species have caused significant impacts to North American forests despite past and present international phytosanitary efforts. Though broadly acknowledged, the risks of pest invasions are difficult to quantify as they involve interactions between many factors that operate across a range of spatial and temporal scales: the transmission of invading organisms via various pathways, their spread and establishment in new environments. Our study presents a stochastic simulation approach to quantify these risks and associated uncertainties through time in a unified fashion. We outline this approach with an example of a forest pest recently detected in North America, Sirex noctilio Fabricius. We simulate new potential entries of S. noctilio as a stochastic process, based on recent volumes of marine shipments of commodities from countries where S. noctilio is established, as well as the broad dynamics of foreign marine imports. The results are then linked with a spatial model that simulates the spread of S. noctilio within the geographical distribution of its hosts (pines) while incorporating existing knowledge about its behavior in North American landscapes. Through replications, this approach yields a spatial representation of S. noctilio risks and uncertainties in a single integrated product. The approach should also be appealing to decisionmakers, since it accounts for projected flows of commodities that may serve as conduits for pest entry. Our 30-year forecasts indicate high establishment probability in Ontario, Quebec, and the northeastern United States, but further southward expansion of S. noctilio is uncertain, ultimately depending on the impact of recent international treatment standards for wood packing materials. 相似文献
62.
Denys Yemshanov Yakov Ben‐Haim Marla Downing Frank Sapio Marty Siltanen 《Risk analysis》2013,33(9):1694-1709
Invasive species risk maps provide broad guidance on where to allocate resources for pest monitoring and regulation, but they often present individual risk components (such as climatic suitability, host abundance, or introduction potential) as independent entities. These independent risk components are integrated using various multicriteria analysis techniques that typically require prior knowledge of the risk components’ importance. Such information is often nonexistent for many invasive pests. This study proposes a new approach for building integrated risk maps using the principle of a multiattribute efficient frontier and analyzing the partial order of elements of a risk map as distributed in multidimensional criteria space. The integrated risks are estimated as subsequent multiattribute frontiers in dimensions of individual risk criteria. We demonstrate the approach with the example of Agrilus biguttatus Fabricius, a high‐risk pest that may threaten North American oak forests in the near future. Drawing on U.S. and Canadian data, we compare the performance of the multiattribute ranking against a multicriteria linear weighted averaging technique in the presence of uncertainties, using the concept of robustness from info‐gap decision theory. The results show major geographic hotspots where the consideration of tradeoffs between multiple risk components changes integrated risk rankings. Both methods delineate similar geographical regions of high and low risks. Overall, aggregation based on a delineation of multiattribute efficient frontiers can be a useful tool to prioritize risks for anticipated invasive pests, which usually have an extremely poor prior knowledge base. 相似文献
63.
64.
While utilizing social networks is common in labor markets and may benefit both firms and laborers, social networks are argued to be unusually important in the popular arts. Prior work in economics on the role of relationships in labor markets has generally focused on the benefits and not the costs. This paper takes a different approach by focusing on both costs and benefits, by examining a specific market where relationships are particularly important. This paper argues that in addition to reducing diversity and creating inherent inequalities, excessive reliance on networks can lead to higher agency costs and lower product quality. 相似文献
65.
Frank Schubert Sonja Engelage 《KZfSS K?lner Zeitschrift für Soziologie und Sozialpsychologie》2011,63(3):431-457
Which mechanisms lead to the fact, that the proportion of women in the academic career ladder is the smaller the further up the qualification and career to full professorship gets? This phenomenon, known as the ??leaky pipeline??, is analysed with a unique retrospective dataset of PhDs who graduated between 1996 and 2002 at universities in the German speaking part of Switzerland. Results show women have a lower scientific productivity and smaller academic networks than men. Moreover, they suffer from structural barriers in the scientific system. However, women stay in the sector of higher education more often than men and habilitate as often as their male colleagues. Transition rate models show no gender differences in the chance of a successful academic career. Because meanwhile women start to study as often as men, today??s picture of the leaky pipeline could be a result of gender inequalities of the past. Future research should examine the role of affirmative action for women in academia and how results from scientific careers can be transferred into the private labour market. 相似文献
66.
Frank W. Guldenmund 《Risk analysis》2010,30(10):1466-1480
Although the concept of safety culture was coined in relation to major accidents like Chernobyl and Piper Alpha, it has been embraced by the safety community at large as a cause for unsafe practice. In this article, three approaches to safety culture are discussed in terms of their underlying concepts of culture and organizational culture. Culture is an intangible, fuzzy concept encompassing acquired assumptions that is shared among the members of a group and that provides meaning to their perceptions and actions and those of others. The basic assumptions that form the essence of a culture are shared, yet tacit, convictions, which manifest themselves subtly in the visible world. As applied by safety researchers, the culture concept is deprived of much of its depth and subtlety, and is morphed into a grab bag of behavioral and other visible characteristics, without reference to the meaning these characteristics might actually have, and often infused with normative overtones. By combining the three approaches, we can resurrect the notion of safety culture and strengthen its analytical potential in understanding the development and implementation of safety management systems. 相似文献
67.
Frank Wells 《Accountability in research》2013,20(1-3):25-38
68.
Frank R. Wake 《Journal of sex research》2013,50(3):170-177
The purpose of the experiment was to examine the acquisition of information about sexuality by 182 ninth‐grade students enrolled in a sex education course. An additional 197 ninth‐grade students in the same school served as a control group. Approximately half the subjects in each group were pretested. Following completion of the course, all subjects were posttested. The major results of the multiple regression analysis indicated that the experimental group scored higher on the posttest than the control group both for the total set of items (N = 24) and for several subscores measuring learning of sex education material. The pretest and posttest scores did not differ for control group subjects. The results indicated: (a) sex education courses can provide important information about sexuality which is not gained in other ways by ninth‐graders; (b) peers may not be important sources of sexual information when alternatives (sex education courses) to peer information are available. 相似文献
69.
This study focuses on the economically disadvantaged position of refugees. We use survey data of refugees from Somalia, Iran, Afghanistan, Iraq, and the former Yugoslavia in the Netherlands, to analyze refugees’ odds of employment and their occupational status. In line with human capital and social capital theory, we find that host country specific education, work experience, language proficiency, and contacts with natives are positively related to the chances of employment and occupational status. The study shows that health problems, integration courses, and the time spent in refugee reception centers form important additional explanations of the economic integration of refugees. 相似文献
70.
Christine L. Young Pistella Frank A. Bonati 《Child and Adolescent Social Work Journal》1999,16(4):305-315
Family communication about adolescent sexual health and behavior promotes adolescent health and family connectedness. However, few studies seek the perspective of adolescents regarding their recommended strategies for family communication. Findings of a survey of female adolescent family planning patients (n = 249) indicated adolescent recommendations for better family communication included treat teen as an equal, 63%; increase parental knowledge about lifestyle and peer pressures, 61%, and improve parental listening skills, 61%. There were no statistically significant differences according to age, pregnancy history, or school enrollment status for suggested strategies for improved communication with parents. Sexually active adolescent daughters expressed interest in maintaining family connectedness and support with increased time for family activities as well as increased quality and quantity of dialogue between the adolescent girl and her parents. 相似文献