36 research outputs found

    Screening and comparative characterization of microorganisms from Iranian soil samples showing ω-transaminase activity toward a plethora of substrates

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    In this study, soil microorganisms from Iran were screened for ω-transaminase (ω-TA) activity based on growth on minimal media containing (rac)-α-methylbenzylamine (rac-α-MBA) as a sole nitrogen source. Then, for the selection of strains with high enzyme activity, a colorimetric o-xylylendiamine assay was conducted. The most promising strains were identified by 16S rDNA sequencing. Five microorganisms showing high ω-TA activity were subjected to determine optimal conditions for ω-TA activity, including pH, temperature, co-solvent, and the specificity of the ω-TA toward different amine donors and acceptors. Among the five screened microorganisms, Bacillus halotolerans turned out to be the most promising strain: Its cell-free extract showed a highly versatile amino donor spectrum toward aliphatic, aromatic chiral amines and a broad range of pH activity. Transaminase activity also exhibited excellent solvent tolerance, with maximum turnover in the presence of 30% (v/v) DMS

    Effect of berberine chloride on caspase-3 dependent apoptosis and antioxidant capacity in the hippocampus of the chronic cerebral hypoperfusion rat model

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    Objective(s): The main goal of the current research was to examine the effects of Berberine (BBR) on apoptotic signaling and hippocampal oxidative stress induced by common carotid artery occlusion. Materials and Methods: Chronic cerebral hypoperfusion (CCH) model was created by occluding the two common carotid arteries (two-vessel occlusion 2VO) permanently. BBR (50 and 100 mg/kg/daily) was intra-gastrically administered to ischemic rats. Neuronal survival was evaluated by Nissl staining. The levels of malondialdehyde (MDA) and antioxidant enzymes, including catalase (CAT) and superoxide dismutase (SOD), along with the activities of caspase 3 were estimated in the hippocampus 2 month after treating the rats with 2VO. Results: According to findings of the present research, the BBR therapy inhibited the neurodegeneration of hippocampus. BBR also significantly decreased the amount of MDA and activity of caspase 3 in the hippocampus. Furthermore, the administration of BBR alleviated the lowered activities of SOD and CAT after 2VO surgery. Conclusion: The antioxidant and antiapoptotic properties of BBR might play important roles in improving functional outcomes and might have significant neuroprotective effects on the CCH damage. © 2019, Mashhad University of Medical Sciences. All rights reserved

    Effect of berberine chloride on caspase-3 dependent apoptosis and antioxidant capacity in the hippocampus of the chronic cerebral hypoperfusion rat model

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    Objective(s): The main goal of the current research was to examine the effects of Berberine (BBR) on apoptotic signaling and hippocampal oxidative stress induced by common carotid artery occlusion. Materials and Methods: Chronic cerebral hypoperfusion (CCH) model was created by occluding the two common carotid arteries (two-vessel occlusion 2VO) permanently. BBR (50 and 100 mg/kg/daily) was intra-gastrically administered to ischemic rats. Neuronal survival was evaluated by Nissl staining. The levels of malondialdehyde (MDA) and antioxidant enzymes, including catalase (CAT) and superoxide dismutase (SOD), along with the activities of caspase 3 were estimated in the hippocampus 2 month after treating the rats with 2VO. Results: According to findings of the present research, the BBR therapy inhibited the neurodegeneration of hippocampus. BBR also significantly decreased the amount of MDA and activity of caspase 3 in the hippocampus. Furthermore, the administration of BBR alleviated the lowered activities of SOD and CAT after 2VO surgery. Conclusion: The antioxidant and antiapoptotic properties of BBR might play important roles in improving functional outcomes and might have significant neuroprotective effects on the CCH damage. © 2019, Mashhad University of Medical Sciences. All rights reserved

    Model of optimization of mining complex for the planning of flow of quarry production of limestone in multiple products and with elements for the analysis of the capacity

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    Activities in mining complexes contain multiple decisions that affect the operations of the system for the extraction, transformation, transport and storage of various subsoil components. The purpose of this research is the planning of continuous flow production systems for mixed products, in non-metallic mining extraction processes, considering bottlenecks and capacity planning. This paper presents a model for production, based on mathematical optimization, that facilitates the planning and management of operations in the area of extraction, crushing and transformation of a quarry of aggregates for construction, considering the resources and the constraints that allow to define effective strategies in the increase of the productivity of the lines of low production environment by scenarios. This research develops an analysis of bottlenecks and contrasts the nature of the production system by means of a mathematical model of optimization, which considers the capacities and balances in the flows of the Limestone production line. The mathematical model that maximizes profits can be adapted to systems of continuous flow production in mining complexes where their products are part of a reverse logistics process, analysis of alternatives of extraction, transformation and transport

    Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry

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    Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry DOI: 10.1080/00207543.2014.975852 Juan A. Marin-Garciaa* & Tomas Bonaviab Received: 1 Aug 2013 Accepted: 30 Sep 2014 Published online: 04 Nov 2014 This research aims to empirically test the effect of employee involvement on lean manufacturing (LM), and the effect of LM on production outcomes. Employee involvement is operationalised through four related variables: empowerment, training, contingent remuneration and communication. The effects are tested by recording management perceptions in a different industrial sector from those usually studied in previous research ceramic manufacturers, a highly competitive and internationally successful sector. We obtained data from 101 ceramic tile plants (64% of response rate) in the Valencia region of Spain. This approach is developed using a statistical method called partial least squares. All paths are significant except for contingent remuneration; specifically, relationships were found between empowerment, training, communication and LM, and between LM and performance.This paper has been written with financial support from the Project "Path Dependence and decision-making for selecting LM tools and practices" (PAID-06-12-SP20120717) of the Universitat Politecnica de Valencia.Marín García, JA.; Bonavía Martín, T. (2015). Relationship between employee involvement and lean manufacturing and its effect on performance in a rigid continuous process industry. International Journal of Production Research. 53(11):3260-3275. https://doi.org/10.1080/00207543.2014.975852S32603275531
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