Showing 6 results for Solgi
Volume 1, Issue 1 (3-2013)
Abstract
Otters at the top of the food chain and feeding largely on fish are likely to be especially vulnerable to the effects of bioaccumulating pollutants. This research reports the first data on mercury levels found in hairs of river otters (Lutra lutra) from Iran. Between June and December 2007, we collected museum and recent collections of river otter hair. These samples were collected from several provinces of three major regions of Iran. The mean of mercury concentration for all samples (recent and museum) was 5.819±1.557 mg/kg with 95% confidence interval for the mean. The concentrations of Total Hg (THg) in hair ranged from 0.293 to 12.382 mg/kg. No significant variation among the sample regions existed. A comparison of THg concentrations between two decades (1986-1996 and 1996-2006) showed that these differences were significant (p
Volume 5, Issue 4 (12-2017)
Abstract
Background: Concentrations of 4 toxic metals, viz. Cd, Cu, Pb, and Zn in the soil and alfalfa samples collected from Borujerd, Iran, was determined. The capability of alfalfa to accumulate heavy metals from soils was assessed in terms of Biological Concentration Factor.
Materials and Methods: The alfalfa and soil samples were collected from 20 different farms, including 13 wastewater-irrigated and seven underground-irrigated farms. After acid digestion, the samples were analyzed using atomic absorption spectrophotometer.
Results: The levels of Cd, Pb, and Zn in the soils of wastewater-irrigated farms were higher than those from the groundwater-irrigated farms. With the exception of Cu, concentrations of heavy metals in the alfalfa crop were higher in wastewater-irrigated farms compared to well water. Also, in the case of BCF, both Cd and Cu values decreased with increasing metal concentration in soil. The order of BCF of heavy metals in alfalfa was in order of Cu>Cd>Zn>Pb in well water-irrigated and Zn>Cd>Cu>Pb in wastewater –irrigated samples.
Discussion and Conclusions: The findings remarked that the levels of Cu, Cd, and Pb in alfalfa were exceeding the permissible levels suggested by the Joint FAO/WHO Expert Committee on Food Additives. These outcomes propose that the consumption of alfalfa plants is potentially threatening both animal and human health.
Z. Solgi, Kh. Khalifeh , S. Hosseinkhani, B. Ranjbar ,
Volume 9, Issue 3 (Summer 2018)
Abstract
Aims: The probability of establishing electrostatic interactions due to the abundance of charged hydrophilic residues and especially arginine is considered the most important thermal stabilizing factor of thermophilic enzymes. The current study was conducted with the aim of comparing thermodynamic stability and kinetic refolding of Lampyris turkestanicus and some of its mutants.
Materials and Methods: In the present experimental thermal stability and the way of refolding Lampyris turkestanicus and 3 mutations, including ERR, ERR/I232R, ERR/Q35R/I182R/I232R were investigated by various spectroscopic techniques. In order to high expression of proteins, a single clone of each sample was selected and inoculated into 10ml of LB culture medium, containing Kanamycin at a concentration of 50μg/mg and incubated at 37°C with an ideal aeration for 12-15 hours. The culture medium was centrifuged for 5 minutes at 5000g at 4°C to provide the cellular contents of the bacteria. The results were obtained through spectroscopic methods of remote and near circular dichroism, intrinsic fluorescence, differential scanning calorimetry, and kinetics experiments, using fluorescence-stopped flow technique.
Findings: Along with the increase in the number of arginine residues at the protein level, the stability and structural compression of the mutated enzymes in comparison with the wild enzyme were increased and the thermograms obtained from differential scanning calorimetry showed a slight increase in Tm and calorimetric enthalpy of mutated proteins in comparison with wild protein.
Conclusion: The rate constant of refolding mutated enzymes has increased compared with the wild type. The improvement of thermodynamic and kinetic parameters results from the improvement of electrostatic interactions, which results in a higher degree of compression and structural density.
Volume 10, Issue 2 (10-2020)
Abstract
Purpose: Due to the emergence of the lean approach concept in human resources, this research was conducted with aim of analyzing the issue of lean human resource supply chain.
Methodology: Relying on philosophical foundations of pragmatism school, this research is a qualitative study based on grounded theory. The statistical population of the study consisted of senior managers, middle managers and experts of the Ministry of Cooperation, Labor and Social Welfare and academic experts. 19 individuals were selected by purposeful sampling as statistical sample members. Lean human resource supply chain model identifications were collected using semi-structured interviews and analyzed using Strauss and Corbin's three-step coding method (252 key concepts, 43 subcategories, and 25 main categories).
Findings: Based on the findings of the study, lean human resource supply was selected as the pivotal phenomenon. Causal conditions were categorized into two categories of environmental and organizational factors, and the five main categories of preventive demand management planning, efficiency of search resources, efficiency of evaluation and screening, recruitment preparation and succession system efficiency. Selected strategy title, personal characteristics of managers, evaluating the effectiveness of absorbed human resources, the employability of the candidate as a reinforcement intervener and illegal relationships, environmental uncertainty, time pressure for employment, and the inefficiencies of the public management system were identified as mitigating interventions. Organizational culture, strategic role of HR unit, managers' flexibility and adaptability, management stability, career management and accessibility, and the organization's resource constraints were identified as lean human resource supply chain strategies. Finally, the implications of the lean human resource supply chain were divided into three levels: micro, middle and macro.
Volume 21, Issue 146 (April 2024)
Abstract
Despite the development of methods to increase the shelf life and safety of food products, the economic loss caused by food spoilage is still considered one of the main challenges of food industry. Due to the culture of the use of natural products and functional foods, the consumer's desire for natural products with extended shelf life has increased. Phenolic compounds, like many bioactive compounds, gradually become inactive and usually cause a bitter taste in food. Microliposome is one of the effective solutions to increase the stability and reduce the unpleasant taste of bioactive compounds. In this research, the Ferula leaves was extracted with ethanol and its phenolic and flavonoid properties were determined. Then, the antioxidant properties of the extract were determined by DPPH and β-carotene/linoleic acid assay at different concentration (400, 800, 1600 and 3200 PPM). Then it was added to beef burger in the form of liposomes and the oxidative, microbial and sensory characteristics and the release rate of phenolic compounds in beef burger were investigated over two weeks’ storage. The results showed that the total phenolic and flavonoid content of the Ferula leaves extract was 270.67 ± 5.8 mgGA/ g extract and 160.81±5.65 mg Quercetin/g extract, respectively. With the increase in the concentration of Ferula extract, the DPPH radical inhibition increases from 33.73 to 84.42% and β-carotene-linoleic acid from 32.56 to 74.90% at 400 to 3200 PPM. The results obtained on the shelf life of beef burger showed that the highest microbial growth and lipid oxidation were observed in the control, and the lowest one was observed in the sample containing 3200 PPM Ferula extract. Based on the oxidation test and sensory evaluation, adding microliposome of Ferula leaves extract at 1600 PPM can significantly increase the shelf life of beef burger in the refrigerator.
Volume 25, Issue 1 (4-2021)
Abstract
The present study was conducted to design a model of lean human resource excellence with a mixed approach and using the qualitative method of data theory and the quantitative method of Shannon entropy. The statistical population of the qualitative part of the study was all senior and middle managers of the Ministry of Cooperatives, Labor and Social Welfare, 19of whom were purposefully selected for interviews and interviews were conducted until the theoretical saturation of the data. To analyze the qualitative data, open, axial and selective coding was used, as a result of which 402 basic concepts in the form of 92 sub-categories and 17main categories and six dimensions of causal conditions (environmental and organizational), contextual conditions ( Organization strategy, culture, management insight, job content documentation, management stability and human resource system dynamics), interventionist conditions (personal characteristics of managers, quality of organizational inputs, efficiency of government management system), strategies (lean leadership, strengthening culture Lean and lean human resource management) and results (micro level, intermediate level and macro level) were included. Then, in order to turn the model designed into a basis for self-assessment of the lean degree of human resources, using the Shannon entrobial method, the weight and score of each dimension were identified, resulting in its application in the Ministry of Cooperatives, Labor and Social Welfare. Ascore of 376 out of 1000 was assigned to the organization under study, which due to its position in the second level of excellence, ie an organization with public awareness oflean human resources
