37 research outputs found

    Biosorption characteristics of Cadmium from environment by one-year old seedlings of Acer velutinum

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    Background and Aims: Heavy metals are elements with high atomic weight and could be harmful for living organisms at higher concentrations. Cadmium is among these metals and may result in various health problems forhuman. The ability of Acer Velutinum in bioremediation of cadmium was considered in the present study.Materials and Methods: One-year old seedlings of Acer Velutinum were provided from Department of Natural Resources making arrangements well in advance. Cadmium chloride solutions were prepared with different concentrations of 0, 10, 20 and 40 mg/L and consequently were added into the soil. The seedlings were planted inpots and their aerial organs (stems and leaves) as well as their roots were separated three month after. The results were then analyzed using Danken and ANOVA tests.Results: The maximum amount of cadmium accumulation in aerial organs, root and soil was 9.67, 60.61 and 12.44 mg/kg, respectively. Similarly, the respective lowest level of cadmium accumulation in aerial organs, root and soil was 6.05, 2.3 and 0.1mg/kg. The least amount of aerial organs (4.45 g) and root (1.25 g) dry weights wereoccurred at 40 mg Ca/L, and the most values of respectively 9.02 and 3.95 g was observed at pristine control pot.Conclusion: Acer Velutinum species is considered as appropriate for bioremediation of soils contaminated by cadmium.Keywords: Cadmium, Adsorption, Heavy metals, Phytoremediation, Acer Velutinu

    Load Balancing Algorithms in Cloud Computing Analysis and Performance Evaluation

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    Distributing the system workload and balancing all incoming requests among all processing nodes in cloud computing environments is one of the important challenges in today cloud computing world. Many load balancing algorithms and approaches have been proposed for distributed and cloud computing systems. In addition the broker policy for distributing the workload among different datacenters in a cloud environment is one of the important factors for improving the system performance. In this paper we present an analytical comparison for the combinations of VM load balancing algorithms and different broker policies. We evaluate these approaches by simulating on CloudAnalyst simulator and the final results are presented based on different parameters. The results of this research specify the best possible combinations

    Zinc absorption in two-year old Poplar seedlings (Populus deltoids) in the environment

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    Background and Aims: Phytoremediation is the use of green plants to reduce contaminant levels such as heavy metals in the environment. Some plants can uptake and store (accumulate) environmental contaminants within their tissue and organs. Due to their sustainability in the environment, heavy metals are of particular significance. This study was, therefore, conducted to evaluate the phytoremediation potential of zinc by Populus deltoids.Materials and Methods: Biennial seedlings of populous deltoids were provided from plantations with arrangements made well in advance with the directors of the Department of Natural Resources. Zinc chloride solutions (0, 10, 20 and 40 mg /L) were prepared, added into the soil and the seedlings were thereafter placed in pots. The seedlings were grown for three months exposing to various zinc concentrations. Seedlings aerial organs (stems and leaves) and roots as well as the soil were sampled and analyzed using atomic absorption spectrometry. Analysis of variance (ANOVA) followed by Duncan’s multiple comparisons (P < 0.05) was performed to test the significance of treatment effects.Results: The highest level of Zn in aerial organs, root and the soil structure of Populous deltoids was 142.86, 85.94, 12.002 mg/kg, respectively. Similarly, the corresponding lowest level of Zn was 44.61, 21.20, and 0.124 mg/kg. The high-zinc (40 mg/L) treated plants showed the lowest levels of 4.14 and 1.03 g/L in aerial organs and root dry weights, respectively. The maximum values of 20.61 and 3.066 were also respectively determined at control experiments.Conclusions: The results suggest that Populous deltoids is an appropriate alternative for phytoremediation of zincpolluted soils

    Program for Editing Spacecraft Command Sequences

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    Sequence Translator, Editor, and Expander Resource (STEER) is a computer program that facilitates construction of sequences and blocks of sequences (hereafter denoted generally as sequence products) for commanding a spacecraft. STEER also provides mechanisms for translating among various sequence product types and quickly expanding activities of a given sequence in chronological order for review and analysis of the sequence. To date, construction of sequence products has generally been done by use of such clumsy mechanisms as text-editor programs, translating among sequence product types has been challenging, and expanding sequences to time-ordered lists has involved arduous processes of converting sequence products to "real" sequences and running them through Class-A software (defined, loosely, as flight and ground software critical to a spacecraft mission). Also, heretofore, generating sequence products in standard formats has been troublesome because precise formatting and syntax are required. STEER alleviates these issues by providing a graphical user interface containing intuitive fields in which the user can enter the necessary information. The STEER expansion function provides a "quick and dirty" means of seeing how a sequence and sequence block would expand into a chronological list, without need to use of Class-A software

    Validation of CRASH Model in Prediction of 14-day Mortality and 6-month Unfavorable Outcome of Head Trauma Patients

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    Introduction: To date, many prognostic models have been proposed to predict the outcome of patients withtraumatic brain injuries. External validation of these models in different populations is of great importancefor their generalization. The present study was designed, aiming to determine the value of CRASH prognosticmodel in prediction of 14-day mortality (14-DM) and 6-month unfavorable outcome (6-MUO) of patients withtraumatic brain injury. Methods: In the present prospective diagnostic test study, calibration and discriminationof CRASH model were evaluated in head trauma patients referred to the emergency department. Variablesrequired for calculating CRASH expected risks (ER), and observed 14-DM and 6-MUO were gathered. Then ERof 14-DM and 6-MUO were calculated. The patients were followed for 6 months and their 14-DM and 6-MUOwere recorded. Finally, the correlation of CRASH ER and the observed outcome of the patients was evaluated.The data were analyzed using STATA version 11.0. Results: In this study, 323 patients with the mean age of 34.0´s 19.4 years were evaluated (87.3% male). Calibration of the basic and CT models in prediction of 14-day and6-month outcome were in the desirable range (P Ç 0.05). Area under the curve in the basic model for predictionof 14-DM and 6-MUO were 0.92 (95% CI: 0.89–0.96) and 0.92 (95% CI: 0.90–0.95), respectively. In addition,area under the curve in the CT model for prediction of 14-DM and 6-MUO were 0.93 (95% CI: 0.91–0.97) and0.93 (95% CI: 0.91–0.96), respectively. There was no significant difference between the discriminations of thetwo models in prediction of 14-DM (p Æ 0.11) and 6-MUO (p Æ 0.1). Conclusion: The results of the presentstudy showed that CRASH prediction model has proper discrimination and calibration in predicting 14-DMand6-MUO of head trauma patients. Since there was no difference between the values of the basic and CT models,using the basic model is recommended to simplify the risk calculations

    The Effect of Low-Frequency Pulsed Electromagnetic Fields on the Differentiation of Permanent Dental Pulp Stem Cells into Odontoblasts

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    Introduction: Exposure to pulsed electromagnetic field (PEMF) has been revealed to affect the differentiation and proliferation of human mesenchymal stem cells derived from dental pulp multipotent stromal stem cells (DP-MSCs). This study aimed to investigate the differentiation effect of electromagnetic fields (EMFs) on the DP-MSC. Materials and Methods: PEMF was produced by a system comprising a multi-meter autotransformer, solenoid coils, and teslameter. This study included 10 groups of DP-MSCs which underwent different electromagnetic radiation time and beam intensity. Three samples tested for each group. The effect of PEMF with the intensity of 0.5 and 1 mT (mili Tesla) and 50 Hz on the proliferation rate of DP-MSC was evaluated at 20 and 40 minutes per day for seven days. MTT assay was applied to determine the growth and proliferation of DP-MSC. Gene expression of DMP1 for differentiation of DPSCs to odontoblasts was confirmed by Real Time PCR., ANOVA statistical analysis and Kruskal-Wallis test were used to analyze the data. Results: The survival in all exposure groups was significantly higher than that in control except in the group of 40 minutes, 1 mT (P<0.05). In 20 minutes, 0.5 mT exposure, the survival intensity is significantly more than others (P<0.05). In general, the intensity of survival was recorded, 20, 0.5 mT≥20, 1 mT≥40, 0.5 mT≥40, 1 mT respectively. Therefore, according to the obtained results, ELF-EMF increases the survival of cells except for one case (40 minutes, 1 mT), even though the effective underlying mechanisms in this process are still unclear. Conclusions: The results obtained promise that in the future, by placing an important part of the pulp next to the electromagnetic field, the lost part of the pulp can be reconstructed and the dentin barrier can be created

    The Investigation of Near-death Experiences, and Necessity of Awareness about its Elements

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    Introduction: Near-death experience (NDE) is a phenomenon with paranormal elements which follows pervasive and deep personal and social changes for patients. The familiarity of medical staff with the components of this phenomenon, and their appropriate response to patients’ experiences could facilitate understanding and integration process of NDEs for patients. Due to the impact of medical staff reaction to patients’ experiences, and the lack of research on NDEs which described the elements, this study aimed to explain the elements of Iranian patients’ NDEs. Method: This qualitative study was performed using a descriptive phenomenological approach. The subjects of the study consisted of 10 people with NDE. They were selected through purposive sampling method. Data were collected via individual tape-recorded interviews, and simultaneously analyzed using Colaizzi’s seven-step analysis method. Results: Through data analysis, 113 codes were extracted which were classified under 11 semantic codes. Then, the 4 main themes of cognitive, spiritual, emotional, and paranormal were extracted from the experiences of the participants. Conclusion: The findings suggest that some patients, during cardiac arrest and resuscitation operation, have experiences which usually follow inappropriate reactions of medical staff. So, accurate knowledge about the NDEs, and appropriate interventions can help patients in coping with their NDEs. Keywords: Qualitative research, Near-death experiences, Cardiac arrest, Medical staf

    COVID-19 Associated Mucormycosis::A Review of an Emergent Epidemic Fungal Infection in 3 Era of COVID-19 Pandemic

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    At a time when the COVID-19's second wave is still picking up in countries like India, a number of reports describe the potential association with a rise in the number of cases of mucormycosis, commonly known as the black fungus. This fungal infection has been around for centuries and affects those people whose immunity has been compromised due to severe health conditions. In this article, we provide a detailed overview of mucormycosis and discuss how COVID-19 could have caused a sudden spike in an otherwise rare disease in countries like India. The article discusses the various symptoms of the disease, class of people most vulnerable to this infection, preventive measures to avoid the disease, and various treatments that exist in clinical practice and research to manage the disease

    Seroprevalence of Immunoglobulin G antibodies against pertussis toxin among asymptomatic medical students in the west of Iran: a cross sectional study

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    <p>Abstract</p> <p>Background</p> <p>Pertussis is a highly communicable, vaccine-preventable respiratory infection. Immune response against this disease can be induced by infection or vaccination. Protection after childhood vaccination is minimal after ten years. Our aim was to assess pertussis immunity state in a population of healthy young medical students.</p> <p>Methods</p> <p>In this seroepidemiological survey, blood samples were obtained from 163 first-year medical students in Hamedan University, Iran. Serum level of IgG against pertussis toxin (IgG-PT) was measured by Enzyme-Linked Immunosorbent Assay (ELISA) method. For qualitative assessment, IgG-PT levels more than 24 unit (U)/ml were considered positive. Data was analysed qualitatively and quantitatively considering gender and age groups.</p> <p>Results</p> <p>There were 83 males and 80 females, with a mean age of 19.48 years, Prevalence of IgG-PT was 47.6% with mean level of 71.7 u/ml (95% confidence interval: 68.1–75.3). No statistically significant difference was observed with respect to sero-positivity of IgG-PT between males and females (45 cases (54%) vs. 34 cases (42%); P = 0.06). Mean IgG-PT levels in males and females were 84 U/ml and 58.8 U/ml, respectively (P = 0.91).</p> <p>Conclusion</p> <p>A considerable proportion of our study population with a positive history of childhood vaccination for pertussis was not serologically immune to pertussis. A booster dose of acellular pertussis vaccine may be indicated in Iranian, medical students regarding their serologic conditions and outstanding role in health care systems.</p

    Modeling and Compensation for Capacitive Pressure Sensor by RBF Neural Networks

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    Abstract-Capacitive differential pressure sensor (CPS) is extremely used in industries. This sensor measures pressure and shows current. Accuracy of capacitive differential pressure sensor is limited because the ambient temperature has adverse effects on CPS output characteristic. In order to overcome this limitation, the output of this sensor is compensated by using RBF neural network and because of the importance of modeling of sensors and for having more correct read out, the model of this sensor is extracted by RBF neural network too. A test bench is designed and implemented to data acquisition in a real environment. The experimental results are being used to verify the performance of RBF neural network based on compensating and modeling of nonlinear system of CPS
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