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31.
Quantifying the Establishment Likelihood of Invasive Alien Species Introductions Through Ports with Application to Honeybees in Australia
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The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port‐specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed‐effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one‐tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports. 相似文献
32.
This article examines how childhood innocence is taken up in (92) memories of undergraduate students across four sites in the US and Canada. Drawing from Foucault's theory of discourse, we examine how three themes—innocence as not knowing, innocence as being provided for, and loss of innocence as exposure to adversity—construct childhood as the absence of conflict, which perpetuates the myth of an innocence/experience binary and encourages a deficit perspective of childhood. These findings contribute to teacher education and childhood studies by highlighting the importance of interrogating adult memories in order to disrupt normative assumptions about children. 相似文献
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This study examines the relative importance of soft skills versus hard skills across occupations and its impact on the observed wage gap between Blacks and Whites in the United States. It posits that the Black/White pay gap may vary across occupations that require the use of different types of skills. We classify occupations into hard‐skill intensive versus soft‐skill intensive jobs using the skill content measures of different occupations from the Occupational Information Network (O*Net). We then use data from the National Longitudinal Survey of Youth (NLSY) and Current Population Survey (CPS) to investigate the impact of job skill type on the wage gap. Consistent with our theoretical predictions, we show that this wage gap in white‐collar jobs is smaller for hard‐skills jobs than it is for soft‐skills jobs. Moreover, we demonstrate that, in response to variations in the wage gap across different occupations, Blacks are more likely to self‐select themselves into hard‐skills jobs, ceteris paribus. This shows not only that discrimination against Blacks varies across occupations, but also that such discrimination induces the self‐selection of Blacks into certain occupations. Moreover, this finding highlights the role played by co‐worker/customer discrimination in explaining the racial wage gap in the U.S. labor market. (JEL J15, J31) 相似文献
35.
The pursuit of operational excellence in the manufacturing industry is at rise but its measurement still lacks of appropriate indicators to determine its financial benefits. The ambiguity is due to the impact arisen from manufacturing fluctuations such as price and cost, production mix and direct and indirect parameters variations. Manufacturing fluctuations distort the cost benefit of operational excellence. This paper, therefore, proposes the OEP (Operational Excellence Profitability) indicators to isolate the impact of manufacturing fluctuation and distinctly identify the payback of operational excellence strategies and initiatives through cost benefits of achieving higher efficiency and yield. The paper presents the conceptual and mathematical development of the proposed OEP indicators and the formulas used for their calculation. Hypothetical and industrial-based investigations and applications of the OEP indicators are conducted for their validation. The results obtained from the hypothetical exercise and industrial case suggest that OEP indicators can provide an effective cost-benefit analysis of operational excellence. This would contribute in providing manufacturing organizations with more complete information regarding the performance of their processes, which will allow their directors and managers to take better decisions related to the management and improvement of their processes. 相似文献
36.
To recover a low-rank structure from a noisy matrix, truncated singular value decomposition has been extensively used and studied. Recent studies suggested that the signal can be better estimated by shrinking the singular values as well. We pursue this line of research and propose a new estimator offering a continuum of thresholding and shrinking functions. To avoid an unstable and costly cross-validation search, we propose new rules to select two thresholding and shrinking parameters from the data. In particular we propose a generalized Stein unbiased risk estimation criterion that does not require knowledge of the variance of the noise and that is computationally fast. A Monte Carlo simulation reveals that our estimator outperforms the tested methods in terms of mean squared error on both low-rank and general signal matrices across different signal-to-noise ratio regimes. In addition, it accurately estimates the rank of the signal when it is detectable. 相似文献
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38.
Fink Matthias Hatak Isabella Scholz Markus Down Simon 《Review of Managerial Science》2020,14(2):335-343
Review of Managerial Science - Third-party funding of academic research has grown rapidly in its scope and impact. However, several forces demand greater attention to potential opportunities,... 相似文献
39.
Introduction: We investigated if “thermobalancing” therapy (TT), using Dr Allen’s therapeutic device (DATD) in men with benign prostatic hyperplasia (BPH), can aid in understanding the etiology and pathophysiology of BPH.Methods: We compared urinary and other parameters of BPH patients who received TT over 6 months (treatment group) with those of healthy volunteers who had not received the treatment (control group). Dynamics of symptoms and indicators in each group were evaluated in comparison with their data at the beginning and end of the study. Parameters were the International Prostate Symptom Score (IPSS) for urinary symptoms and quality of life (QoL), ultrasound measurement of prostate volume (PV) and uroflowmetry (maximum flow rate, Qmax). TT effectiveness was examined in 124 men with BPH and PV?<60?mL. We also investigated the data of five patients with BPH and PV?>60?mL.Results: TT decreased urinary symptoms and PV, increased Qmax and improved QoL in men with BPH, PV?<60?mL, and in men with BPH, PV?>60?mL.Conclusions: The present study demonstrated that TT is effective for BPH, suggesting that blood circulation plays a crucial role in its cause. The continuous heat exposure that does not exceed the normal body temperature terminates the trigger of BPH development, “micro-focus” of hypothermia, and the following spontaneous expansion of capillaries. TT could be considered to be a useful tool in BPH treatment. 相似文献
40.
A number of studies have suggested breastfed infants have improved bonding and attachment or cognitive development outcomes.
However, mechanisms by which these differences might develop are poorly understood. We used maternal time use data to examine
whether exclusively breastfeeding mothers spend more time in close interactive behaviors with their infants than mothers who
have commenced or completed weaning. Mothers (188) participating in a time use survey recorded infant feeding activities for
24 h over a 7 day period using an electronic device. Tracking was conducted at 3, 6, and 9 months postpartum. Data was collected
for maternal activities including infant feeding and time spent in emotional care. The mothers of exclusively breastfed infants
aged 3–6 months fed them frequently and total time spent in breastfeeding averaged around 17 h a week. Maternal time spent
in emotional care was also substantial, and found to correlate positively with time spent breastfeeding. Exclusively breastfed
infants received greatest amounts of emotional care from their mother, and exclusively formula fed infants the least. Mixed
fed infants received more emotional care time than formula fed infants, but less than fully breastfed infants. These findings
may help explain the differential cognitive developmental outcomes reported in the medical literature for breastfed and non
breastfed infants. 相似文献