Electrospun nanofibers and nanocomposites

The use of fine fiber has become an important design tool for filter media. Nanofibers based filter media have some advantages as lower energy consumption, longer filter life, high filtration capacity, easier maintenance, low weight rather than other filter media. The nanofibers based filter media made up of fibers of diameter ranging from 100 to 1000 nm can be conveniently produce by electrospinning technique. Common filter media have been prepared with a layer of fine fiber on typically formed the upstream or intake side of the media structure. The fine fiber increases the efficiency of filtration by trapping small particles which increases the overall particulate filtration efficiency of the structure. Improved fine fiber structures have been developed in this study in which a controlled amount of fine fiber is placed on both sides of the media to result in an improvement in filter efficiency and a substantial improvement in lifetime. In the first part of this study, the production of electrospun nanofibers investigated. In the second part, a different case study presented to show how they can be laminated for application as filter media. Response surface methodology (RSM) was used to obtain a quantitative relationship between selected electrospinning parameters and average fiber diameter and its distribution

Oscillatory and chaotic regimes of patterns and dark cavity solitons in cavities displaying EIT : static multihead dual chimera states

Oscillating and chaotic regimes of honeycomb patterns and dark cavity solitons are studied in a cavity displaying electromagnetically induced transparency. Considering a three-level atomic system in a configuration, transition to chaotically oscillating honeycombs is numerically investigated and their dynamical behavior is detailed for different control parameter values. We show that a branch of oscillating dark cavity solitons coexists with the honeycomb patterns. These oscillating cavity solitons are studied individually and in mutual interaction. In particular, it is shown that mutually coherent oscillating dark cavity solitons can be obtained by choosing an appropriate separation distance. Finally, we introduce a novel regime of chimera states consisting of a multitude of identically and non-locally coupled dark cavity solitons in which regions of in-phase and anti-phase coherence separated by incoherent areas coexist and are stationary. We discuss the unique features of these structures and categorize them as static multihead dual chimera states. We believe that this is the first time that such chimeric states are reported in a photonic system hosting oscillating and chaotic structures

Studying effect of Ncentive-Based Compensation on Managerial Performance

This study examines the effect of incentive-based compensation schemes on managerial performance by clarifying the role of information asymmetry and organizational commitment as mediator. The research method in terms of purpose is among the descriptive and survey research data collection tool is questionnaire. The population of the study area was East Bank Saderat Gilan province. 183 people are selected with cluster way as sampling. Data is analyzed using structural equation modeling. The results suggest a positive effect of incentive - based compensation variable on managerial performance. The results also showed the positive effect of incentive - based compensation variable on managerial performance with considering the moderating role of organizational commitment. The results also reflect the negative impact of incentive- based compensation on information asymmetry as well as information asymmetry on the managerial performance

Evaluation of vitamin D status and its correlation with oxidative stress markers in women with polycystic ovary syndrome

Background: There is little evidence about antioxidant properties of vitamin D. Recent studies suggest that oxidative stress may play a major role in the pathophysiology of polycystic ovary syndrome (PCOS), but the association of vitamin D with oxidative stress is still not known in PCOS. Objective: The goal of the present study was to evaluate the correlation between serum 25-hydroxy vitamin D and oxidative stress markers in PCOS group compared to control group. Materials and Methods: 60 PCOS women (20-40 yr old) and 90 healthy women as control group were participated in this case-control study. Fasting serum level of 25-hydroxy vitamin D 25(OH) D, glucose, insulin, calcium, malondialdehyde (MDA), protein carbonyl (PC), also homeostasis model assessment for insulin resistance (HOMA-IR) and fasting glucose to insulin ratio (FGIR) were measured. Results: It was found that the mean of serum 25(OH)D was lower in the PCOS group (10.76±4.17) than in the control group (12.07±6.26) but this difference was not statistically significant (p=0.125). Fasting insulin, HOMA-IR and MDA were significantly higher in the PCOS patients as compared to the controls, whereas PC level did not differ for the two groups (p=0.156). No significant correlations were found between 25(OH) D levels and oxidative stress markers (MDA and PC). Conclusion: The findings indicated no significant differences in the serum 25(OH) D levels between the PCOS patients and the matched controls. Also, no correlation was found between the serum vitamin D levels and oxidative stress markers in both group