Stability Properties of Underdominance in Finite Subdivided Populations

In isolated populations underdominance leads to bistable evolutionary dynamics: below a certain mutant allele frequency the wildtype succeeds. Above this point, the potentially underdominant mutant allele fixes. In subdivided populations with gene flow there can be stable states with coexistence of wildtypes and mutants: polymorphism can be maintained because of a migration-selection equilibrium, i.e., selection against rare recent immigrant alleles that tend to be heterozygous. We focus on the stochastic evolutionary dynamics of systems where demographic fluctuations in the coupled populations are the main source of internal noise. We discuss the influence of fitness, migration rate, and the relative sizes of two interacting populations on the mean extinction times of a group of potentially underdominant mutant alleles. We classify realistic initial conditions according to their impact on the stochastic extinction process. Even in small populations, where demographic fluctuations are large, stability properties predicted from deterministic dynamics show remarkable robustness. Fixation of the mutant allele becomes unlikely but the time to its extinction can be long

The use of mesenchymal stem cells for cartilage repair and regeneration: a systematic review.

BACKGROUND: The management of articular cartilage defects presents many clinical challenges due to its avascular, aneural and alymphatic nature. Bone marrow stimulation techniques, such as microfracture, are the most frequently used method in clinical practice however the resulting mixed fibrocartilage tissue which is inferior to native hyaline cartilage. Other methods have shown promise but are far from perfect. There is an unmet need and growing interest in regenerative medicine and tissue engineering to improve the outcome for patients requiring cartilage repair. Many published reviews on cartilage repair only list human clinical trials, underestimating the wealth of basic sciences and animal studies that are precursors to future research. We therefore set out to perform a systematic review of the literature to assess the translation of stem cell therapy to explore what research had been carried out at each of the stages of translation from bench-top (in vitro), animal (pre-clinical) and human studies (clinical) and assemble an evidence-based cascade for the responsible introduction of stem cell therapy for cartilage defects. This review was conducted in accordance to PRISMA guidelines using CINHAL, MEDLINE, EMBASE, Scopus and Web of Knowledge databases from 1st January 1900 to 30th June 2015. In total, there were 2880 studies identified of which 252 studies were included for analysis (100 articles for in vitro studies, 111 studies for animal studies; and 31 studies for human studies). There was a huge variance in cell source in pre-clinical studies both of terms of animal used, location of harvest (fat, marrow, blood or synovium) and allogeneicity. The use of scaffolds, growth factors, number of cell passages and number of cells used was hugely heterogeneous. SHORT CONCLUSIONS: This review offers a comprehensive assessment of the evidence behind the translation of basic science to the clinical practice of cartilage repair. It has revealed a lack of connectivity between the in vitro, pre-clinical and human data and a patchwork quilt of synergistic evidence. Drivers for progress in this space are largely driven by patient demand, surgeon inquisition and a regulatory framework that is learning at the same pace as new developments take place

The Process of Molting and the Number of Instars in the Tiger Beetle Cicindela cancellata Coleoptera Cicindelidae

Volume: 70Start Page: 221End Page: 22

A Simple Case of Learning in the Ant Camponotus sp Hymenoptera Formicidae

Volume: 69Start Page: 211End Page: 21

Observations on a Mode of Food Capture by Dragonflies

Volume: 65Start Page: 803End Page: 80

Cannibalism in the Coffee Bean Weevil Araecerus fasciculatus Coleoptera Anthribidae

Volume: 69Start Page: 210End Page: 21

Observations on the Mating Behavior in the Ant Monomorium gracillimum Hymenoptera Formicidae

Volume: 67Start Page: 350End Page: 35

On the Mechanism of Escape by a Moth from Accidental Drowning

Volume: 65Start Page: 798End Page: 79

A Convenient Method of Rearing Tiger Beetles Coleoptera Cicindelidae in the Laboratory for Biological and Behavioral Studies

Volume: 69Start Page: 209End Page: 21

A Study on Employee Retention as a Tool for Improving Organizational Effectiveness

Background/Purpose: Human sources are those who make the group of workers of a company. It's also recognized via manpower, skills, labour, employees etc. Human Resource department of a business enterprise performs human useful resource control.  It entails various elements of the employment consisting of compliance with labour regulation and employment standards, management of worker benefits, and various other sports related to recruitment and choice of the employee.  Worker retention is regarding the efforts with the aid of which employers try and retain the personnel in their team of workers. Retention turns into the strategies in place of the final results. Preserving the worker for long duration of time is known as retention. Retention strategies of the organization need to have the capacity to attract and hold their staff. Organizational effectiveness refers to a company's ability to achieve the goals it sets out to achieve.  It's far the performance of the organization, group or an organization to fulfill its goal. Six Sigma is a methodology that makes a specialty of improving the overall efficiency of a business process. Objective: This work is carried out at Dinesh Foods, Kannur. Dinesh foods are a subsidiary unit of Kerala Dinesh Beedi Workers Co-op Society. The objective of this study is to observe and to recognize how worker retention facilitates in growing the organizational effectiveness of Dinesh Foods. It additionally assists to investigate diverse retention techniques followed and also the employee turnover within the unit.  This work investigates the worker retention is a device for increasing the organizational effectiveness.  Design/Methodology/Approach: For the purpose of study the data was collected through primary and secondary source.  Questionnaire was distributed among the workers for collecting necessary data for the study, financial statement of the company to study about the financial stability of the organisation and annual report of the company. Findings/Results: This research is done to find out whether the employee retention in the organisation helps in improving the organisational effectiveness. Varies conditions applied for the hypothesis and it can be proved that the employee retention is a tool for increasing the organisational effectiveness.  Based on the analysis, findings and suggestions Dinesh Foods, Kannur can give more concentration towards retaining the employees in the organisation as it is important in any organization. Conclusion: This study focusses on whether employee retention is a tool for improving the organisational effectiveness. It is found that the employee retention is a tool for improving organisational effectiveness and employee retention helps in increasing the productivity. Paper Type: Case study-based Research Analysi