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11.
Smith E Lally F Stone MA Shaw JS Nash GB Buckley CD Ed Rainger G 《Microscopy research and technique》2006,69(11):875-884
The use of fluorescent probes that allow visualization of leukocyte-endothelial cell (EC) interactions has greatly informed our understanding of leukocyte recruitment. However, effects of these agents on the biological functions of leukocytes are poorly described, leading to concerns about the interpretation of such data. Here we used two flow-based neutrophil adhesion assays to compare the effects of phase contrast illumination (PCI) with high intensity illumination (HII) used for fluorescent microscopy, in the presence or absence of five commonly used fluorochromes. Isolated neutrophils were either (1) perfused across P-selectin to establish a population of rolling cells, which were subsequently activated with fMLP; or (2) perfused across EC activated with TNF-alpha. In the absence of fluorescent dyes, HII did not affect levels of leukocyte adhesion; however, subsequent neutrophil behavior was dramatically altered when compared with cells under PCI, for example, dramatically reducing their migration velocities. In the presence of fluorescent dyes, the effects of HII were exacerbated, although the precise nature of the biological effects of these probes was agent specific. Thus, for the first time, our experiments describe the effects of fluorescent microscopy on the separate stages of the neutrophil recruitment process and reveal a previously unsuspected effect of HII on neutrophil migration. 相似文献
12.
LinkedIn, with over 1.5 million Groups, has become a popular place for business employees to create private groups to exchange information and communicate. Recent research on social networking sites (SNSs) has widely explored the phenomenon and its positive effects on firms. However, social networking's negative effects on information security were not adequately addressed. Supported by the credibility, persuasion and motivation theories, we conducted 1) a field experiment, demonstrating how sensitive organizational data can be exploited, followed by 2) a qualitative study of employees engaged in SNSs activities; and 3) interviews with Chief Information Security Officers (CISOs). Our research has resulted in four main findings: 1) employees are easily deceived and susceptible to victimization on SNSs where contextual elements provide psychological triggers to attackers; 2) organizations lack mechanisms to control SNS online security threats, 3) companies need to strengthen their information security policies related to SNSs, where stronger employee identification and authentication is needed, and 4) SNSs have become important security holes where, with the use of social engineering techniques, malicious attacks are easily facilitated. 相似文献
13.
This work deals with the employee rostering problem at the airport. Such problems, related to the time varying demand of the transport services, use many (e.g., about a hundred) diverse shifts to cover the workforce demand during the day. Together with the strict constraints, given by the collective agreement, the problem becomes difficult to solve. Algorithms commonly used for solving the usual employee rostering problems produce poor quality rosters, which are unusable in practice. This paper suggests a three stage approach allowing one to solve the employee rostering problems where a huge set of different shifts is used to satisfy the coverage requirements. The solution is based on the problem transformation to a simpler problem, thereupon, an evolutionary algorithm is used to determine a rough position of the shifts in the roster. Afterwards, the maximal weighted matching in the bipartite graph is applied as the inverse transformation of the problem and the final roster is obtained by the optimization based on a Tabu Search algorithm. This multistage approach is compared to other approaches. Furthermore, an evaluation methodology was proposed in order to make a complex and fair comparison. Its objective is to verify the contribution of the particular stages used in the different approaches applied on the different personnel scheduling problems. 相似文献
14.
Ani Birgit Raiden Andrew R. J. Dainty Richard H. Neale 《Construction Management & Economics》2013,31(11):1133-1143
In recent years the literature on employee resourcing has consistently advocated the importance of adopting a holistic, strategic approach to employee deployment decision making rather than adopting a reactive needs‐based approach. This is particularly problematic in construction where the multi‐project environment leads to constantly changing resource requirements and to changing demands over a project's life cycle. This can lead to inappropriate decisions, which fail to meet the longer‐term needs of both construction organizations and their employees. A structured and comprehensive understanding of the current project team deployment practices within large construction organizations was developed. Project deployment practices were examined within seven case study contracting firms. The emergent themes that shaped the decision‐making processes were grouped into five broad clusters comprising human resource planning, performance/career management, team deployment, employee involvement and training and development. The research confirms that a reactive and ad hoc approach to the function prevails within the firms investigated. This suggests a weak relationship between the deployment process and human resource planning, team deployment, performance management, employee involvement and training and development activities. It is suggested that strategic HR–business partnering could engender more transparent and productive relationships in this crucial area. 相似文献
15.
The natural flow regime and the relationship between flows and riparian vegetation are described for sites on both the Blackwood River in south‐western Australia and the Ord River in north‐western Australia. Analysis of long‐term flow data showed the historic mean monthly river discharge for the Blackwood River is strongly seasonal and highly predictable with generally low variability each month. The Ord River showed a strong seasonality of flows with about 92% of the (total) yearly flow occurring between December and March. Flow variability was very high (e.g. coefficient of variation >100% for all months) but highly predictable, with this mostly attributed to low but constant dry‐season flows. Water depth, duration of flood events and the number of flood events per year show a significant correlation with aspects of the riparian vegetation within experimental vegetation plots. Results highlight the strong relationship between floristics, life form structure and population dynamics with stream hydrology. On the Blackwood River, species richness and cover of shrubs reduced with increased duration and frequency of flooding, while cover of exotic species and annual herbs increased with increased flooding. Germination of tree seedlings was not influenced by flood regime but size class of tree species increased with flooding frequency. On the Ord River, species richness was not influenced by flooding regime. However, cover of perennial grasses increased with flooding frequency whilst cover of shrubs decreased. There was no relationship between flooding and seedling establishment whilst tree size class decreased with increased flooding. The methods described here can be used to compare the response of different components of the riparian vegetation to different fluvial regimes (e.g. because of impoundment and abstraction). This technique can be expanded for the management of riparian zones and planning rehabilitation programmes. It may also be useful for improving the ecological knowledge base for setting environmental flows in regulated systems. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
16.
Many psychology departments are striving for a greater representation of students of color within their graduate preparation programs with the aim of producing a more diverse pool of psychological service providers, scientists, and educators. To help improve the minority pipeline in psychology, the authors identify and describe recruitment and retention strategies used at 11 departments and programs considered to be making exemplary efforts to attract and retain minority students of color. The strategies most consistently used included engaging current minority faculty and students in recruitment activities, offering attractive financial aid packages, having faculty members make personal contacts with prospective students, creating linkages with historical institutions of color, having (or approached having) a critical mass of faculty and students of color, offering a diversity issues course, and engaging students in diversity issues research. Despite the similarities, the programs and departments were each distinctive and innovative in their overall approaches to student recruitment and retention. Highlighting the strategies used at successful institutions may help others develop plans for improving the minority pipeline within their own departments and programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
Vasquez Melba J. T.; Lott Bernice; García-Vázquez Enedina; Grant Sheila K.; Iwamasa Gayle Y.; Molina Ludwin E.; Ragsdale Brian L.; Vestal-Dowdy Elise 《Canadian Metallurgical Quarterly》2006,61(2):157
In this article, six faculty and students of color who participated in a panel discussion at a symposium during the National Multicultural Conference and Summit of 2003 talk about the barriers they encountered and continue to encounter in their graduate training and places of employment. They also discuss strategies they found to be effective, enhancing, and positive and suggest other possibilities. The contributors describe their relationships with dominant-group and minority peers and talk about how issues of social class, disability, and sexual orientation as well as color have been part of their experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
基于免疫更新机制的遗传算法及其在规划问题中的应用 总被引:4,自引:0,他引:4
受生物体免疫系统抗体更新机制的启发,将抗体更新机制引入遗传算法,从而保证抗体遗传子的多样性,有效地防止了遗传操作中的早期收敛。对遗传子进行分段编码以对应多道染色体,进而克服了传统遗传算法只能对二值染色体进行操作的缺陷。应用实例证明了该方法的有效性。 相似文献
19.
In this article, the authors assessed job seekers' organizational image beliefs before and after they experienced 3 recruitment media. The authors examined whether perceptions of media richness and credibility were related to improvements in the correspondence between job seekers' image beliefs and firms' projected images. Both media richness and credibility perceptions were associated with correspondence between job seekers' image beliefs and firms' projected images. However, results revealed that richness and credibility perceptions were likely to enhance job seekers' initial beliefs about firms' images when their beliefs were positive but did not diminish job seekers' beliefs about firms' images when their initial impressions were too positive. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.