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61.
62.
The Fish Invasiveness Scoring Kit (FISK) is currently one of the most popular pre‐screening tools for freshwater fishes. A recent upgrade has ensured its wider climatic relevance to countries with subtropical regions. This enhancement is of particular importance to Australia, which encompasses tropical, arid, and temperate zones, and where the introduction of non‐native fish species poses a significant risk to biodiversity. In this study, 55 fish species previously evaluated in a U.K.‐based calibration of FISK are reassessed for their potential invasiveness in the Murray‐Darling Basin (MDB; southeastern Australia), the continent's largest catchment encompassing arid and temperate climates. Approximately half of the species were classed as “medium risk” and the other half as “high risk,” and the ≥19 threshold previously identified from the calibration study was confirmed. The three highest scoring species (common carp Cyprinus carpio carpio, goldfish Carassius auratus, and eastern mosquitofish Gambusia holbrooki) were those already present and invasive in the area, whereas nearly half of the tropical and subtropical species had lower scores compared to U.K. assessments, possibly because of climate change predictions of drier conditions across the MDB. There were some discordances between FISK and two Australian‐based assessment protocols, one of which is qualitative and the other represents a simplified version of FISK. Notably, the Australian origins of FISK should provide for an additional reason for further applications of the tool in other RA areas (i.e., drainage basins) of the continent, ultimately encouraging adoption as the country's reference screening tool for management and conservation purposes. 相似文献
63.
Larry L. Lawson Jr. Jeffrey E. Hill Lorenzo Vilizzi Scott Hardin Gordon H. Copp 《Risk analysis》2013,33(8):1414-1431
The initial version (v1) of the Fish Invasiveness Scoring Kit (FISK) was adapted from the Weed Risk Assessment of Pheloung, Williams, and Halloy to assess the potential invasiveness of nonnative freshwater fishes in the United Kingdom. Published applications of FISK v1 have been primarily in temperate‐zone countries (Belgium, Belarus, and Japan), so the specificity of this screening tool to that climatic zone was not noted until attempts were made to apply it in peninsular Florida. To remedy this shortcoming, the questions and guidance notes of FISK v1 were reviewed and revised to improve clarity and extend its applicability to broader climatic regions, resulting in changes to 36 of the 49 questions. In addition, upgrades were made to the software architecture of FISK to improve overall computational speed as well as graphical user interface flexibility and friendliness. We demonstrate the process of screening a fish species using FISK v2 in a realistic management scenario by assessing the Barcoo grunter Scortum barcoo (Terapontidae), a species whose management concerns are related to its potential use for aquaponics in Florida. The FISK v2 screening of Barcoo grunter placed the species into the lower range of medium risk (score = 5), suggesting it is a permissible species for use in Florida under current nonnative species regulations. Screening of the Barcoo grunter illustrates the usefulness of FISK v2 as a proactive tool serving to inform risk management decisions, but the low level of confidence associated with the assessment highlighted a dearth of critical information on this species. 相似文献
64.
Martijn Bouwknegt Jack F. Schijven Johanna A.C. Schalk Ana Maria de Roda Husman 《Risk analysis》2013,33(7):1228-1236
Quantitative microbiological risk assessment was used to quantify the risk associated with the exposure to Legionella pneumophila in a whirlpool. Conceptually, air bubbles ascend to the surface, intercepting Legionella from the traversed water. At the surface the bubble bursts into dominantly noninhalable jet drops and inhalable film drops. Assuming that film drops carry half of the intercepted Legionella, a total of four (95% interval: 1–9) and 4.5×104 (4.4×104 – 4.7×104) cfu/min were estimated to be aerosolized for concentrations of 1 and 1,000 legionellas per liter, respectively. Using a dose‐response model for guinea pigs to represent humans, infection risks for active whirlpool use with 100 cfu/L water for 15 minutes were 0.29 (~0.11–0.48) for susceptible males and 0.22 (~0.06–0.42) for susceptible females. A L. pneumophila concentration of ≥1,000 cfu/L water was estimated to nearly always cause an infection (mean: 0.95; 95% interval: 0.9–~1). Estimated infection risks were time‐dependent, ranging from 0.02 (0–0.11) for 1‐minute exposures to 0.93 (0.86–0.97) for 2‐hour exposures when the L. pneumophila concentration was 100 cfu/L water. Pool water in Dutch bathing establishments should contain <100 cfu Legionella/L water. This study suggests that stricter provisions might be required to assure adequate public health protection. 相似文献
65.
Gordon H. Copp Lorenzo Vilizzi John Mumford Gemma V. Fenwick Michael J. Godard Rodolphe E. Gozlan 《Risk analysis》2009,29(3):457-467
Adapted from the weed risk assessment (WRA) of Pheloung, Williams, and Halloy, the fish invasiveness scoring kit (FISK) was proposed as a screening tool for freshwater fishes. This article describes improvements to FISK, in particular the incorporation of confidence (certainty/uncertainty) ranking of the assessors' responses, and reports on the calibration of the score system, specifically: determination of most appropriate score thresholds for classifying nonnative species into low-, medium-, and high-risk categories, assessment of the patterns of assessors' confidences in their responses in the FISK assessments. Using receiver operating characteristic (ROC) curves, FISK was demonstrated to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative fishes, with the statistically appropriate threshold score for high-risk species scores being ≥19. Within the group of species classed as high risk using this new threshold, a "higher risk" category could be visually identified, at present consisting of two species (topmouth gudgeon Pseudorasbora parva and gibel carp Carassius gibelio ). FISK represents a useful and viable tool to aid decision- and policymakers in assessing and classifying freshwater fishes according to their potential invasiveness. 相似文献
66.
T. F. Gordon 《Journal of applied statistics》1985,12(2):147-155
Statistical tests of significance are carried out on the feedback shift register pseudo-random number generator employed on the BBC microcomputer. The tests are based on the practicalities of using a microcomputer in simulations for statistical education. The results indicate that the generator is not universally acceptable in this role. 相似文献
67.
Despite a recognized need for a global mindset, opportunities for US business school students to gain hands‐on diversity training regarding intercultural issues remain rare. The reasons for this neglect include a lack of agreement on how to teach intercultural awareness and a paucity of faculty qualified to do so. In order to introduce intercultural education into a core business course, students were offered the opportunity to participate in an extra‐credit project that required the development of a proposal for an international joint venture and afforded them the chance to learn about each other while pursuing a superordinate goal of value to each. Thirty‐nine cross‐cultural teams were created, each of which had a partner from the US and a partner from a different country. Both quantitative and qualitative analyses revealed that the value of the project was closely related to the amount of learning that reportedly took place in both the business and cultural realms. Importantly, 73% of the students reported a strong interest in meeting people from different cultures as a result of participation in the project. 相似文献
68.
Laurie Mook Femida Handy Jack Quarter 《Voluntas: International Journal of Voluntary and Nonprofit Organizations》2007,18(1):55-71
Volunteer contributions in the production of services are an important resource internationally. However, few countries include volunteer contributions in their national accounts, even though many encourage their populations to engage in volunteering. At the organizational level, many nonprofit organizations using volunteers often limit their input to a footnote in annual reports acknowledging their contribution; few estimate their value in financial terms. As a result, their financial accounts lack information upon which to base decisions affecting the organizations and the communities they serve. Additional information is required to assess the impact of volunteers in individual nonprofits as well as the sector as a whole. This study focuses on Canada, one of the few countries that include volunteers in the national accounts, to examine to what extent nonprofit organizations estimate a financial value for these contributions and include this in their financial statements. This paper reports the results of an online survey of 661 nonprofits from across Canada. In order to understand why some organizations keep records for volunteer contributions and quantify them, two sets of explanatory factors are explored: organizational characteristics and the attitude of the executive director. We find larger organizations were more likely to engage in record keeping and estimating volunteer value, as were organizations with a relatively large group of volunteers and volunteer programs. The attitude of the executive director is important in determining which organizations engage in these practices. 相似文献
69.
Sidartha Gordon 《Social Choice and Welfare》2007,29(1):125-147
We study the implications of two solidarity conditions on the efficient location of a public good on a cycle, when agents
have single-peaked, symmetric preferences. Both conditions require that when circumstances change, the agents not responsible
for the change should all be affected in the same direction: either they all gain or they all loose. The first condition,
population-monotonicity, applies to arrival or departure of one agent. The second, replacement-domination, applies to changes in the preferences of one agent. Unfortunately, no Pareto-efficient solution satisfies any of these properties.
However, if agents’ preferred points are restricted to the vertices of a small regular polygon inscribed in the circle, solutions
exist. We characterize them as a class of efficient priority rules. 相似文献
70.
An effective and efficient search algorithm has been developed to select from an 1(1) system zero-non-zero patterned cointegrating and loading vectors in a subset VECM, Bq(l)y(t-1) + Bq-1 (L)Ay(t) = ε( t ) , where the long term impact matrix Bq(l) contains zero entries. The algorithm can be applied to higher order integrated systems. The Finnish money-output model presented by Johansen and Juselius (1990) and the United States balanced growth model presented by King, Plosser, Stock and Watson (1991) are used to demonstrate the usefulness of this algorithm in examining the cointegrating relationships in vector time series. 相似文献