The Effects of Job Security, Features, Personal Values, and Recognition on Organizational Involvement

As extrinsic rewards become very limited under organizational retrenchments, organizations should rely heavily on other types of rewards, such as intrinsic rewards, to improve the performance of those employees who have been overwhelmed with a perception of job insecurity. This paper examines the impact of such perception, along with many other positive influencers such as enhancement in job features, recognition, and the personal values of those employees on the organizational involvement. The data analyzed were based on a sample of 34 employee respondents from a project based engineering and service company （identified as ABC Company in this paper） operating in the Middle East. The adopted research approach is basically a quantitative approach. The correlation and regression analysis tools have been used to explore this relationship. The results of this study suggest a generally unnoticed and disregarded resource that has the prime effect on improving and enhancing the organizational involvement, which is the recognition those employees receive from the management. This research suggests that recognition, as the top influencer, has a strong impact on organizational involvement/psychological attachment for the employees. The other factors that have proved to have the second degree influence on organizational involvement are enhancement in job features, increase in the job security level, and personal values.

Finite sample breakdown point of Tukey＇s halfspace median

Tukey's halfspace median(HM), servicing as the multivariate counterpart of the univariate median,has been introduced and extensively studied in the literature. It is supposed and expected to preserve robustness property(the most outstanding property) of the univariate median. One of prevalent quantitative assessments of robustness is finite sample breakdown point(FSBP). Indeed, the FSBP of many multivariate medians have been identified, except for the most prevailing one—the Tukey's halfspace median. This paper presents a precise result on FSBP for Tukey's halfspace median. The result here depicts the complete prospect of the global robustness of HM in the finite sample practical scenario, revealing the dimension effect on the breakdown point robustness and complimenting the existing asymptotic breakdown point result.

Development of a colorimetric assay for rapid quantitative measurement of clavulanic acid in microbial samples

We developed a colorimetric assay to quantify clavulanic acid （CA） in culture broth of Streptomyces clavuligerus, to facilitate screening of a large number of S. clavuligerus mutants. The assay is based on a β-1actamase-catalyzed reaction, in which the yellow substrate nitrocefin （λmax=390 nm） is converted to a red product （λmax=486 nm）. Since CA can irreversibly inhibit β-1actamase activity, the level of CA in a sample can be measured as a function of the A390]A486 ratio in the assay mixture. The sensitivity and detection window of the assay were determined to be 50 μg L -1 and 50 μg L to 10 mg L-1, respectively. The reliability of the assay was confirmed by comparing assay results with those obtained by HPLC. The assay was used to screen a pool of 65 S. clavuligerus mutants and was reliable for identifying CA over-producing mutants. Therefore, the assay saves time and labor in large-scale mutant screening and evaluation tasks. The detection window and the reliability of this assay are markedly better than those of previously reported CA assays. This assay method is suitable for high throughput screening of microbial samples and allows direct visual observation of CA levels on agar plates.