435 research outputs found

    Phoma negriana, a new invasive pathogen for Moghan's vineyards in Iran

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    During disease diagnosing studies in Moghan area, northern west of Iran, symptoms of black rot and necrosis were observed for the first time on Vitis venifera. Incidence was first noticed on leaves and stems. Symptoms occurred as small brown spots on leaves and stems, and developed as blackishbrown necrosis/canker so that the black pycnidia extended at the central parts of them. On the fruit, symptoms appeared as mummification of berries that were visible in the infested vineyards until winter time. The loss due to the disease along with downy mildew was remarkable during the studied years and can lead to substantial yield losses in Moghan climate condition. In order to identify the causal agent, the pathogen was isolated from infected leaves and stems. Also pathogenesity test was carried out by inoculating the causal agent to grapevine cuttings. According to culture, pycnidia and conidia characteristics described by Boerema et al. (2004), the results pointed toward Phoma negriana Thum asthe causative organism

    Optimization of the antifungal activity of essential oil isolated from aerial parts of Thymus kotschyanus Boiss & Hohen (Lamiaceae)

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    Although utilization of synthetic chemicals is inevitable for management of economically detrimental agents, numerous side-effects such as environmental contaminations and effects of non-target organisms associated with them. Plant essential oils with low/without toxicity on mammals and as bio-degradable natural materials have been considered for different pests and fungi management in the recent years. In the present study, the essential oil of Thymus kotschyanus isolated by a Clevenger apparatus and its mycelial growth inhibition was measured against two phytopathogenic fungi Botrytis cinerea and Fusarium graminearum. The best models for predicting of antifungal effects were quadratic models. The essential oil showed a prospective mycelial growth inhibition against both phytopathogenic fungi. Optimization of the antifungal effects indicated that 206.207 ppm of the essential oil caused 50% mycelial growth inhibition of B. cinerea after 89.651 h. This value was 85.600 ppm for F. graminearum within 117.194 h. Results of the present study designated a great potential of T. kotschyanus essential oil for management of pathogenic fungi B. cinerea and F. graminearum.Keywords: Essential oil, mycelial growth inhibition, response surface, Thymus kotschyanu

    Effect of pulsed power on particle matter in diesel engine exhaust using a DBD plasma reactor

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    Nonthermal plasma (NTP) treatment of exhaust gas is a promising technology for both nitrogen oxides (NOX) and particulate matter (PM) reduction by introducing plasma into the exhaust gases. This paper considers the effect of NTP on PM mass reduction, PM size distribution, and PM removal efficiency. The experiments are performed on real exhaust gases from a diesel engine. The NTP is generated by applying high-voltage pulses using a pulsed power supply across a dielectric barrier discharge (DBD) reactor. The effects of the applied high-voltage pulses up to 19.44 kVpp with repetition rate of 10 kHz are investigated. In this paper, it is shown that the PM removal and PM size distribution need to be considered both together, as it is possible to achieve high PM removal efficiency with undesirable increase in the number of small particles. Regarding these two important factors, in this paper, 17 kVpp voltage level is determined to be an optimum point for the given configuration. Moreover, particles deposition on the surface of the DBD reactor is found to be a significant phenomenon, which should be considered in all plasma PM removal tests

    The feasibility and benefits of using high-strength concrete for construction purposes in earthquake prone areas

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    In recent years, concrete technology has benefited from great advances and evolutions that lead to emergence of new concrete with different properties. One of the most important of these concretes is high strength concrete (HSC). The emergence of HSC has made possible to high-rise buildings and towers with architectural art and delicacy and it is expected that in the next few years, there is the possibility of using HSC in wider areas. Examining the studies on this type of concrete, this paper has deal with the feasibility and benefits of using HSC for construction purposes in earthquake prone areas. The results of this study show that in case of respecting the bylaw constrains and conformity of new bylaws with this type of concrete, it is hoped to use it as a reliable option for safe construction in seismic areas.Keywords: Concrete, High-Strength, Construction, Seismic Area, Feasiblit

    Evaluation of bacterial and fungal contamination in the health care workers? hands and rings in the intensive care unit

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    Introduction. Nosocomial infections remain a major challenge to the health care system and result in significant mortality, morbidity, and economic burden. Intensive care unit (ICU) patients are at great risk of acquiring nosocomial infections. The objective of this study was to determine the contamination rate (bacterial and fungal) of the health care workers? (HCWs?) hands and ring in ICU. Methods. All health care workers were screened during the day shift in Emam hospital ICU. After obtaining informed consent, convenience samples of HCWs? hands and rings were cultured on specific media during their routine work hours, always after a patient care episode. The fungal and bacterial isolates were identified using standard microbiological procedures. Results. A total of 40 subjects were selected in this study (28females, 12males). The rate of contamination of hands and rings was observed in 73.1%. Most of isolates are known to cause nosocomial infections which included: 23% staphylococci, 7.9% Klebsiella spp., 4.7% Enterobacter spp., 3.9% Escherichia coli, 3.1% Acinetobacter spp., 2.3% Pseudomonas spp., and 27.7% were colonized with fungi. The fungal isolates were 16.6% Candida spp., 3.9% Rhodotorula spp., 3.1% Aspergillus niger, and 3.9% Aspergillus flavus. Conclusion. According to these results HCWs? hands and their rings were contaminated with various types of microorganisms. Medical and hospital personals must follow careful hand-washing techniques to minimize transmission of disease and should remove rings, watches, and bracelets before washing their hands and entering the ICU

    Direct, residual and cumulative effects of organic manures and biofertilizers on yields, NPK uptake, grain quality and economics of wheat (Triticum aestivum L.) under organic farming of rice-wheat cropping system

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    Field experiments were conducted at the research farm of the Indian Agricultural Research Institute, New Delhi during rabi (winter) season of 2007-2008 and 2008-2009 on a sandy clay loam soil (typical Ustochrept, 51.46% sand, 23.02% silt and 25.52% clay) of low in organic C (0.57%), medium in available phosphorus (19.87 kg/ha), high in available potassium (247.12 kg/ha) and low in available nitrogen (163.2 kg/ha) and of pH 8. Results revealed that the cumulative effects of farmyard manure (FYM) and green manure (GM) were more effective than their direct and residual effects and GM was significantly superior to FYM for increasing the productivity, nutrient uptake, grain quality and gross and net income of wheat in the rice-wheat cropping system. Further, inoculation of biofertilizers (B) with GM was better than GM alone in its cumulative effect. The combination of GM + FYM was still better than GM or FYM alone in its direct and cumulative effects for increasing productivity and gross return, but net return was significantly reduced due to the higher cost of GM + FYM compared to FYM or GM alone. However, the residual effect of GM + FYM was similar to the cumulative effects of GM or FYM alone. The highest increase in productivity, grain quality and nutrient uptake was recorded with the application of GM + FYM + B. However, net return was significantly reduced due to the higher cost incurred in the combination of GM + FYM + B. It was concluded that the cumulative effect of GM + FYM + B for higher productivity and the cumulative effect of GM + B for higher net return were suitable for wheat in organic farming of the rice-wheat cropping system

    Three embedded techniques for finite element heat flow problem with embedded discontinuities

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    The present paper explores the solution of a heat conduction problem considering discontinuities embedded within the mesh and aligned at arbitrary angles with respect to the mesh edges. Three alternative approaches are proposed as solutions to the problem. The difference between these approaches compared to alternatives, such as the eXtended Finite Element Method (X-FEM), is that the current proposal attempts to preserve the global matrix graph in order to improve performance. The first two alternatives comprise an enrichment of the Finite Element (FE) space obtained through the addition of some new local degrees of freedom to allow capturing discontinuities within the element. The new degrees of freedom are statically condensed prior to assembly, so that the graph of the final system is not changed. The third approach is based on the use of modified FE-shape functions that substitute the standard ones on the cut elements. The imposition of both Neumann and Dirichlet boundary conditions is considered at the embedded interface. The results of all the proposed methods are then compared with a reference solution obtained using the standard FE on a mesh containing the actual discontinuity

    Direct, residual and cumulative effects of organic manures and biofertilizers on yields, NPK uptake, grain quality and economics of wheat (Triticum aestivum L.) under organic farming of rice-wheat cropping system

    Get PDF
    Field experiments were conducted at the research farm of the Indian Agricultural Research Institute, New Delhi during rabi (winter) season of 2007-2008 and 2008-2009 on a sandy clay loam soil (typical Ustochrept, 51.46% sand, 23.02% silt and 25.52% clay)of low in organic C (0.57%), medium in available phosphorus (19.87 kg/ha), high in available potassium (247.12 kg/ha) and low in available nitrogen (163.2 kg/ha) and of pH 8. Results revealed that the cumulative effects of farmyard manure (FYM) and green manure (GM) were more effective than their direct and residual effects and GM was significantly superior to FYM for increasing the productivity, nutrient uptake, grain quality and gross and net income of wheat in the rice-wheat cropping system. Further,inoculation of biofertilizers (B) with GM was better than GM alone in its cumulative effect. The combination of GM + FYM was still better than GM or FYM alone in its direct and cumulative effects for increasing productivity and gross return, but net return was significantly reduced due to the higher cost of GM + FYM compared to FYM or GM alone. However, the residual effect of GM + FYM was similar to the cumulative effects of GM or FYM alone. The highest increase in productivity, grain quality and nutrient uptake was recorded with the application of GM + FYM + B. However, net return was significantly reduced due to the higher cost incurred in the combination of GM + FYM + B. It was concluded that the cumulative effect of GM + FYM + B for higher productivity and the cumulative effect of GM + B for higher net return were suitable for wheat in organic farming of the rice-wheat cropping system

    IgG anti-apolipoprotein A-1 antibodies in patients with systemic lupus erythematosus are associated with disease activity and corticosteroid therapy: an observational study.

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    IgG anti-apolipoprotein A-1 (IgG anti-apoA-1) antibodies are present in patients with systemic lupus erythematosus (SLE) and may link inflammatory disease activity and the increased risk of developing atherosclerosis and cardiovascular disease (CVD) in these patients. We carried out a rigorous analysis of the associations between IgG anti-apoA-1 levels and disease activity, drug therapy, serology, damage, mortality and CVD events in a large British SLE cohort
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