Chain-Based Anonymous Routing for Wireless Ad Hoc Networks

Wireless ad hoc networks are so vulnerable to passive attacks and eavesdropping adversaries due to their shared medium which makes network traffic easy to capture and analyze. Therefore, security and privacy protections are of extreme importance for protocols and applications in such networks. In this paper, we introduce a new framework for anonymous routing, named chain-based routing, to improve the privacy. In our framework, nodes on a path are virtually bound to each other like a chain. Each node is only aware of its associated links in a flow and does not require any other information about source, destination, or other parts of the chain. Based on this framework, we propose an on-demand routing protocol, called Chain-based Anonymous Routing (CAR), which uses unicast-based broadcast data transfer to fulfill anonymous communication in wireless ad hoc networks. Through hiding identifiers of nodes inside the chain, CAR realizes sender, receiver, and relationship anonymity in addition to untraceability in the network. Moreover, it is resistant to a wide range of passive attacks while adapting to implement other security mechanisms in the presence of active attacks

Estimation and prediction of avoidable health care costs of cardiovascular diseases and type 2 diabetes through adequate dairy food consumption: a systematic review and micro simulation modeling study

Background: Recent evidence from prospective cohort studies show a relationship between consumption of dairy foods and cardiovascular diseases (CVDs) and type 2 diabetes mellitus (T2DM). This association highlights the importance of dairy foods consumption in prevention of these diseases and also reduction of associated healthcare costs. The aim of this study was to estimate avoidable healthcare costs of CVD and T2D through adequate dairy foods consumption in Iran. Methods: This was a multistage modelling study. We conducted a systematic literature review in PubMed and EMBASE to identify any association between incidence of CVD and T2DM and dairy foods intake, and also associated relative risks. We obtained age- and sex-specific dairy foods consumption level and healthcare expenditures from national surveys and studies. Patient level simulation Markov models were constructed to predict the disease incidence, patient population size and associated healthcare costs for current and optimal dairy foods consumption at different time horizons (1, 5, 10 and 20 years). All parameters including costs and transition probabilities were defined as statistical distributions in the models, and all analyses were conducted by accounting for first and second order uncertainty. Results: The systematic review results indicated that dairy foods consumption was inversely associated with incidence of T2DM, coronary heart disease (CHD) and stroke. We estimated that the introduction of a diet containing 3 servings of dairy foods per day may produce a $0.43 saving in annual per capita healthcare costs in Iran in the first year due to saving in cost of CVD and T2DM treatment. The estimated savings in per capita healthcare costs were$8.42, $39.97 and$190.25 in 5, 10 and 20-years’ time, respectively. Corresponding total aggregated avoidable costs for the entire Iranian population within the study time horizons were $33.83,$661.31, $3,138.21 and$14,934.63 million, respectively. Conclusion: Our analysis demonstrated that increasing dairy foods consumption to recommended levels would be associated with reductions in healthcare costs. Further randomized trial studies are required to investigate the effect of dairy foods intake on cost of CVD and T2DM in the population

DeepSpeed-Chat: Easy, Fast and Affordable RLHF Training of ChatGPT-like Models at All Scales

ChatGPT-like models have revolutionized various applications in artificial intelligence, from summarization and coding to translation, matching or even surpassing human performance. However, the current landscape lacks an accessible, efficient, and cost-effective end-to-end RLHF (Reinforcement Learning with Human Feedback) training pipeline for these powerful models, particularly when training at the scale of billions of parameters. This paper introduces DeepSpeed-Chat, a novel system that democratizes RLHF training, making it accessible to the AI community. DeepSpeed-Chat offers three key capabilities: an easy-to-use training and inference experience for ChatGPT-like models, a DeepSpeed-RLHF pipeline that replicates the training pipeline from InstructGPT, and a robust DeepSpeed-RLHF system that combines various optimizations for training and inference in a unified way. The system delivers unparalleled efficiency and scalability, enabling training of models with hundreds of billions of parameters in record time and at a fraction of the cost. With this development, DeepSpeed-Chat paves the way for broader access to advanced RLHF training, even for data scientists with limited resources, thereby fostering innovation and further development in the field of AI.Comment: 14 pages, 7 figure

Rapamycin protects testes against germ cell apoptosis and oxidative stress induced by testicular ischemia-reperfusion

Objective(s):Rapamycin is an immunosuppressant compound with a broad spectrum of pharmaco-logical activities. In recent years, it has been used successfully to decrease ischemia-reperfusion injury in several organ systems. The purpose of the present study was to examine the effect of rapamycin on testicular ischemia-reperfusion injury. Materials and Methods: Seventy-two adult male Wistar rats were divided into six groups: control (group1), sham-operated (Group2), T/D + DMSO as vehicle group (group3), and groups 4–6; respectively received 0.5, 1, and 1.5 mgkg-1 of rapamycin , IP 30 min before detorsion. Ischemia was achieved by twisting the right testis 720o clockwise for 1 hr. The right testis of 6 animals from each group were excised 4 hr after detorsion for the measurement of lipid peroxidation, caspase-3, and antioxidant enzyme activities. Histopathological changes and germ cell apoptosis were determined by measuring mean of seminiferous tubules diameters (MSTD) and TUNEL test in right testis of 6 animals per group, 24 hr after detorsion. Results: Testicular T/D caused increases in the apoptosis, malondialdehyde (MDA), and caspase-3 levels and decreases in the superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities in ipsilateral testis (

Oral Health Literacy and its Determinants in Young Couples

Objectives: Oral health literacy (OHL) is an interplay of cultural, social and individual factors and plays an effective role in public health promotion. This study aimed to assess OHL and its socioeconomic and demographic determinants among young couples. Materials and Methods: This analytical cross-sectional study was conducted on 828 adults between 15 to 35 years in 2018 in Zanjan city. Data regarding their OHL were collected by using a 17-item Oral Health Literacy-Adult Questionnaire (OHL-AQ) that was filled out by a combination of self-report and interview. OHL was categorized as adequate, marginal, and inadequate. The effects of age and gender as demographic variables, and floor area per person as a proxy of financial status on OHL were also assessed. Data were analyzed using the linear and multinomial logistic regression models. Results: The mean OHL score was 7.86±3.83 out of 17 in equal number of males and females. Only 21% of the couples had adequate OHL. The socioeconomic, but not demographic variables had significant correlations with the qualitative and quantitative variables of OHL even after controlling for the effect of confounders. A correlation was particularly found between inadequate OHL and years of education [odds ratio:6.00; 95% CI: 3.86-9.28); P<0.001]. Conclusion: Socioeconomic factors had independent correlations with inadequate OHL. Participants with higher levels of education, those living in urban areas, and individuals with better financial status had higher levels of OHL and lower odds of inadequate OHL

Presenting the Course of Community Dentistry as Problem Based Learning Workshop and Comparing It to Learning through Lecture

Introduction: Nowadays, the attitudinal aspect of community dentistry course and the way in which this course is taught is critically important. The aim of this study is to compare the presentation of theoretical community dentistry course through workshops using PBL method with that of contemporary method of lecture. Methods: In this quasi experimental study, 64 dental students of Tehran University of Medical Sciences who took the course of community dentistry in second semester of academic year of 2006-2007 were entered into the survey through census. They were randomly allocated into two groups of experiment and control each including thirty two. The course of community dentistry was taught to control group through traditional method in 17 lecturing sessions meanwhile this course was instructed to experiment group through problem based learning method. A questionnaire was used for gathering data. Data was analyzed by SPSS software using descriptive statistics and Chi². Results: The improvement in attitude of PBL group was significant in contrast with that of traditional method group. In post-test, the mean score of knowledge and attitude of the group attending in workshop was higher than that of traditional group but the difference was not statistically significant. The mean score of satisfaction and transferring educational concepts was significantly higher in the group attending in workshop. Eighty one percent of the workshop attendees were satisfied with the method employed in the course. Conclusion: The new method of education has been successful in its achievements as forming a positive atti-tude in students and making them eager for community dentistry issues

The Effect of Socio-Personal Factors on Economic and Managerial Variables in Shahroud Commercial Dairy Farms

The purpose of this research was to study the effects of fourpersonal and social variables including the age, literacy,job experience and size of herd on different variables such asimplementing of managerial strategies in transition period,relevant costs of these strategies, average production per headand gross income of milk sale per head. For this purpose allrequired information were collected through questionnairedistribution among the owners of commercial dairy farms ofShahroud district. This questionnaire was included three parts.Relevant information about personal and social indices wasinserted in first part. Second part included of relevant informationabout performance and non-performance of considered managerialstrategies in transition period and third part was aboutrelevant information about production and economic records.Finally all information about 50 herds was obtained andcompared as well. Data analysis was through applying MultipleLinear Regression (MLR) method. Also it was possible tospecify any relation among independent and dependent variablesthrough calculation of Pearson Correlation Coefficient. Finallyit was revealed that social and personal factors have a significanteffect on the implementation of management strategies andother independent factors