RPDP: An Efficient Data Placement based on Residual Performance for P2P Storage Systems

Storage systems using Peer-to-Peer (P2P) architecture are an alternative to the traditional client-server systems. They offer better scalability and fault tolerance while at the same time eliminate the single point of failure. The nature of P2P storage systems (which consist of heterogeneous nodes) introduce however data placement challenges that create implementation trade-offs (e.g., between performance and scalability). Existing Kademlia-based DHT data placement method stores data at closest node, where the distance is measured by bit-wise XOR operation between data and a given node. This approach is highly scalable because it does not require global knowledge for placing data nor for the data retrieval. It does not however consider the heterogeneous performance of the nodes, which can result in imbalanced resource usage affecting the overall latency of the system. Other works implement criteria-based selection that addresses heterogeneity of nodes, however often cause subsequent data retrieval to require global knowledge of where the data stored. This paper introduces Residual Performance-based Data Placement (RPDP), a novel data placement method based on dynamic temporal residual performance of data nodes. RPDP places data to most appropriate selected nodes based on their throughput and latency with the aim to achieve lower overall latency by balancing data distribution with respect to the individual performance of nodes. RPDP relies on Kademlia-based DHT with modified data structure to allow data subsequently retrieved without the need of global knowledge. The experimental results indicate that RPDP reduces the overall latency of the baseline Kademlia-based P2P storage system (by 4.87%) and it also reduces the variance of latency among the nodes, with minimal impact to the data retrieval complexity

Yield and Some Physiological Characteristics in Maize by Application of Bio and Chemical Fertilizers Under Drought Levels

The effects of bio and chemical fertilizers on yield and some of physiological characteristics in maize under drought stress levels, were studied by an experiment in the research field of agricultural faculty, university of kurdistan in 2011. The experiment was arranged in split plot based on randomized complete block design with three replications. Three irrigation levels containing optimal irrigation (irrigation at soil water potential -3 bar), moderate drought stress (irrigation at soil water potential -7 bar) and severe water stress (irrigation at soil water potential -11 bar) were allocated to main plots and four fertilizer levels including no fertilizer (control), chemical fertilizer, bio-fertilizer and a combination of biological and chemical fertilizer (100% biological + 50% chemical) were considered as sub factor. Results showed that water deficit stress had negative effects on yield, and the fertilizer application could not prevent reduction of grain yield under severe drought stress condition. The highest grain yield was obtained under optimum irrigation and application of combinational treatment chemical fertilizer + phosphate-biofertilizer + nitroxin with an average of yield 13 ton.ha-1 that showed a 257 percent increase in comparison with control. The chlorophyll a content was decreased, but chlorophyll b content was decreased with increasing stress intensity. The results showed that catalase and peroxidase enzymes activity were increased in drought stress conditions more than optimal irrigation condition. The application of fertilizer partly mitigated the effects of drought stress and reduced antioxidant enzymes activity

Factors Affecting the Development of Sports Entrepreneurship (Case Study: Ardabil Province in Iran)

Entrepreneurship plays a crucial role in the economic and sustainable development of all countries. The current research aimed to identify the opportunities and threats of the external environment of sports entrepreneurship in Ardabil, Iran based on the PESTLE model by examining the past and existing processes. A mixed approach was used to collect and analyze the research data. The research tool consisted of interviews and strategic council meetings. Theoretical and snowball sampling methods were used to reach the theoretical saturation (15 Experts). For analyzing the collected data in the qualitative section, a logical inductive method was used. The findings revealed that strategic environmental components of entrepreneurship in Ardabil province included: Ecological factors, Cultural and Social Factors, Political factors, Legal and juridical factors, Economic Factors, & Technological factors. According to the findings, considering the extracted factors in the process of spot entrepreneurship management can pave the way for developing entrepreneurship in sport setting

The Effect of Tramadol Addiction on Convulsion and Related Factors

Background: Tramadol is a drug used to control severe pain. Various side effects of this drug have been reported, one of the most important is seizures. The exact cause of tramadol-induced seizures is not known. The aim of this study was to investigate the effect of tramadol addiction on convulsion and related factors in 2018. Methods: This cross-sectional study was performed on 216 patients with convulsion referred to Imam Hossain Hospital of Shahroud in 2018. After reviewing and stabilizing vital signs, a questionnaire containing demographic information, medical history, medication use (especially tramadol), and drugs was completed by patients. The association between recurrent convulsion and predictors were assessed using multivariable logistic regression. Data were analyzed and compared using SPSS statistical software, version 16 and related statistical tests. The significant level was set at 0.05. Results: In this study from 216 participants, 154 (71.3%) of them were male and the rest were female. The mean age of the all patients was 44.8±18.2 years (17-72 years) that was no significant difference between the two groups. Recurrent convulsion was significantly associated with history of opium use (Pvalue<0.032) and tramadol using (Pvalue<0.001) and there was no significant relationship with other variables. Tramadol using cans double your chances of having a recurrent convulsion [OR=2 (95% CI: 1.752 – 2.689)]. Conclusions: The results of this study showed that taking tramadol in opium users can increase the incidence of recurrent convulsion, but more research is needed to fully confirm this. Key words: Tramadol, Convulsion, Side effect

Design and Psychometrics of an Assessment Tool for University Characteristics as a Learning Organization from the perspective of Educational Leaders

Introduction: Universities as learning organizations are places for transcendence, teaching, research and offering knowledge. The aim of this study was to design and assess psychometric properties of an assessment tool for university characteristics as a learning organization from the perspective of educational leaders. Methods: This mixed methods research was performed on faculty members of Tehran and Iran Universities of Medical Sciences in 2013. Drawing on focus group discussions (24 subjects), a preliminary 63-item tool was designed, and then the items were reduced to 59 in three Delphi rounds (30 subjects). The validity of the tool was verified by item impact method and using 10 faculty members and content validity ratio and index was evaluated by the opinions of 12 experts. Exploratory factor analysis with a sample of 200 was used to verify construct validity, and internal consistency test (Cronbach’s alpha) with a sample of 20 was used to verify reliability. Results: Forty items out of 59 items were selected after calculating the scores of item impact, content validity ratio and content validity index with values higher than 1.5, 0.56 and 0.79 respectively. Drawing on the factors analysis of the mentioned items, 40 items were kept. Taking higher than 1 eigenvalue, they were grouped into seven factors: leadership, individual competency, knowledge management, team learning, information management, performance assessment, change facilitation. The proposed tool is able to predict 64.4% of the total changes in characteristics of the learning organization. Conclusion: The results of this study provide solid evidence for the robust factor structure and reliability of the assessment tool for university characteristics as a learning organization. These results could be used by other researchers to develop this tool in other scientific centers

Evaluation of Association Between HLA Class II DR4–DQ8 Haplotype and Type I Diabetes Mellitus in Children of East Azerbaijan State of Iran

Purpose: Association between HLA-DR4–DQ8 haplotype and type 1 Diabetes Mellitus (DM-1A) was investigated in children of East Azerbaijan state of Iran because such an association has not been previously studied in this population. Methods: HLA-typing was performed by polymerase chain reaction sequence-specific priming. For haplotype analysis, the logistic regression model was performed. Results: Of the three investigated alleles, the frequency of DRB1*0401 was significantly higher among patients compared with that in healthy subjects (76.74% vs. 23.26%). Conclusion: The findings of the current study are consistent with those of previous studies and show that DRB1*0401 is associated with DM-1A; the frequencies of the two other alleles were also higher among patients, although the differences were not statistically significant. Two haplotypes associated with these alleles were also surveyed, and DRB1*0401−-DQA1*0301−, and DRB1*0401−-DQA1*0301−-DQB1*0302− were the most frequent haplotypes among the patient group

A Potential Therapeutic Role of Myoinositol in the Metabolic and Cardiovascular Profile of PCOS Iranian Women Aged between 30 and 40 Years

Introduction. Polycystic ovary syndrome (PCOS) is a common disorder in reproductive age. This pilot study investigated the effects of myoinositol (MI) treatment on metabolic and cardiovascular profile in PCOS women over 30 years of age. Methods. Between 2015 and 2016, 50 women with diagnosis of PCOS by the Rotterdam Criteria were included in the study. All women received MI 2 g plus 200 μg of folic acid (Inofolic, Health Parsian, Iran; twice daily) for 3 months. Baseline and 3-month serum samples were taken after an overnight fast to evaluate the insulin resistance index (HOMA-IR), fasting glucose, and the levels of triglyceride, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), homocysteine, systolic blood pressure, and diastolic blood pressure. Participants’ weight was measured before and after treatment and body mass index (BMI) was calculated. Results. The data showed a significant improvement in the serum level of insulin sensitivity and a reduction of cholesterol, LDL, and homocysteine after three months of treatment. Furthermore, blood pressure was significantly reduced in the treated patients. Three participants became pregnant during treatment. Conclusion. Results showed that supplementation with MI and folic acid in PCOS patients over 30 years of age could decrease the risk of cardiovascular problems by normalizing the metabolic profile