Isolation of Fusarium fujikuroi antagonistic bacteria and cloning of its phenazine carboxylic acid genes

Bakanae disease caused by Fusarium fujikuroi is very important in rice. Pseudomonas fluorescens produces a broad-spectrum antibiotic phenazine-carboxylic acid (PCA), which is active against a variety of fungal root pathogens. In this study contaminated rice samples were collected from infected farms of Guilan. 238 bacteria were isolated from rhizosphere and the antagonistic ability of 12 of them was demonstrated with two culture method. Eight of these isolates were identified as P. fluorescens. The effects of volatile metabolites produced by antagonistic P. fluorescens found in the isolates inhibited growth of F. fujikuroi in vitro. Culture filtrate and antibiotics from these isolates inhibited growth of the pathogen. Two genes from seven gene locus of phenazine were cloned in Escherichia coli DH5

What Immunological Defects Predispose to Non-tuberculosis Mycobacterial Infections?

Nontuberculous mycobacteria (NTM) are categorized as one of the large and diverse groups of environmental organisms which are abundant in water and soil.  NTM cause a variety of diseases in humans that mainly affect the lung. A predisposition to pulmonary NTM is evident in patients with parenchymal structural diseases including bronchiectasis, emphysema, tuberculosis (TB), cystic fibrosis (CF), rheumatologic lung diseases and other chronic diseases with pulmonary manifestations. Lung infections are not the only consequences of being infected by NTM as they can also infect skin and soft tissue and may also cause lymphadenitis (predominantly in young children) and disseminated disease in human immunodeficiency virus (HIV)-infected patients or those with severely compromised immune system. NTM are also found in many subjects without any known risk factors.  Although the recent advances in imaging and microbiologic techniques including gene sequencing have provided a better view of the problems caused by NTM and has enhanced our understanding of the disease, many uncertainties regarding the immunologic response to NTM still exist. There is also limited data on the immunogenetics of NTM infection. Here, the authors reviewed the main immunogenetic defects as well as other immunological conditions which are associated with an increased the risk of NTM infections

Association between vitamin d deficiencies in sarcoidosis with disease activity, course of disease and stages of lung involvements

Background: Despite negative association between 25-hydroxy vitamin D and incidence of many chronic respiratory diseases, this feature was not well studied in sarcoidosis. Current study investigated the association between 25-hydroxy vitamin D deficiency with sarcoidosis chronicity, disease activity, extra-pulmonary skin manifestations, urine calcium level and pulmonary function status in Iranian sarcoidosis patients. Results of this study along with future studies, will supply more effective programs for sarcoidosis treatment. Methods: Eighty sarcoidosis patients in two groups of insufficient serum level and sufficient serum level of 25-hydroxy vitamin D were studied. Course of sarcoidosis was defined as acute and chronic sarcoidosis. Pulmonary function test (PFT) was assessed by spirometry. Skin involvements were defined as biopsy proven skin sarcoidosis. 24-hour urine calcium level was used to specify the disease activity. Stages of lung involvements were obtained by CT-scan and chest X-ray. The statistical analyses were evaluated using Statistical Package for the Social Sciences. Results: A significant negative correlation was obtained between vitamin D deficiency in sarcoidosis patients and disease chronic course and stages two to four of lung involvements. Considering other parameters of the disease and vitamin D deficiency, no significant correlation was detected. Conclusions: In conclusion, results of the current study implies in the role of vitamin 25(OH)D deficiencies in predicting the course of chronic sarcoidosis. Furthermore, it was concluded that vitamin 25(OH)D deficiency can direct pulmonary sarcoidosis toward stage 2–4 of lung involvements

Explaining the mutual relationship between board gender diversity and corporate social responsibility using the simultaneous equations system

One of the issues that have gained a lot of attention in recent years is the board gender diversity. Many researchers believe that gender diversity in the board reinforces corporate social responsibility and on the other hand, gender diversity is one of the signs and effects of corporate social responsibility in the board, so there is a mutual relationship between board gender diversity and corporate social responsibility that has not been noticed up to this time. Our study fills this gap in literature by using the Simultaneous equations system. We use data from 110 companies listed in the Tehran Stock Exchange during the 2012 to 2017 period. The results indicate that board gender diversity and corporate social responsibility have a positive and significant effect on each other. As a result, companies can improve their social responsibility by increasing gender diversity in the board, and on the other hand to prove their social responsibility, it is better to use women on the board

Algebraic acceleration and regularization of the source reconstruction method with the recompressed adaptive cross approximation

We present a compression algorithm to accelerate the solution of source reconstruction problems that are formulated with integral equations and defined on arbitrary three-dimensional surfaces. This compression technique benefits from the adaptive cross approximation (ACA) algorithm in the first step. A further error-controllable recompression is applied after the ACA. The numerical results illustrate the efficiency and accuracy of the proposed method. © 2014 IEEE

Solution of low-frequency electromagnetics problems using hierarchical matrices

Fast and accurate solutions of low-frequency electromagnetics problems are obtained with an iterative solver based on hierarchical matrices. Iterative solvers require matrix-vector multiplications (MVMs). The results show significant reductions both in CPU time and memory consumption compared to the O(N2) complexity of ordinary matrix filling and MVM

Fast solution of electromagnetic scattering problems with multiple excitations using the recompressed adaptive cross approximation

We present an algebraic compression technique to accelerate the computation of multiple monostatic radar cross sections of arbitrary 3-D geometries. The method uses adaptive cross approximation, followed by a recompression technique to reduce the CPU time and the memory consumption. Each scattering problem due to a single excitation is solved with the multilevel fast multipole algorithm. The numerical results demonstrate the efficiency and accuracy of the proposed method. © 2014 IEEE

A framework for rating corporate social responsibility disclosure.

Corporate social responsibility (CSR) has become one of the standard business practices of our time. For companies, the overall aim is to achieve a positive impact on society as a whole while maximising the creation of shared value for the owners of the business, its employees, shareholders and stakeholders. Consequently, there has also been an increase in the number of social reporting requirements driven by regulatory bodies and stock exchanges around the world that have played a key role in advancing the field of corporate social reporting. The present study contributes to this field and by adopting Delphi method and identifying the dimensions, components and indicators of social responsibility disclosure, a framework for assessing CSR disclosure incorporating 3 dimensions, 22 components and 68 indicators was designed. Then, these dimensions, components and indicators were ranked by using expert’s views and the results show that the ratios of environmental, social and economic dimensions are 0.55, 0.35 and 0.1, respectively. Among the indicators, the measures taken to reduce greenhouse gas emissions, its technologies, and greenhouse gas elimination criteria with the ratio of 0.06 were considered as the most important indicator. Also, the review of CSR disclosure reports of 330 companies for year 1396 indicates that only 9 out of 68 indicators were disclosed by each of the companies on average, and in the total sample, the highest number of disclosures is related to economic indicators with 1632 cases followed by social indicators with 1490 cases and environmental indicators with only 360 cases, which represent 27.5%, 11.5%, and 7% of the disclosure cases, respectively. Meanwhile, the study shows that 85 of the 330 companies did not disclose any of the environmental indicators, which indicates that some companies still do not pay adequate attention to the most important aspect of social responsibility disclosure