Generating a Shortest B-Chain using Multi-GPUs

Let B be a finite set of binary operations over the set of natural numbers N. A B-chain for a natural number n, denoted by BC(n), is a sequence of numbers 1 = c0,c1,...,cl = n such that for each i \u3e 0,ci = cj ◦ck, where 0 ≤ j,k ≤ i−1 and ◦ is an operation of B. Generating a shortest B-chain for n plays an important role in increasing the performance of some cryptosystems and protocols. This paper has two purposes. The first is to propose a generic algorithm to generate a shortest B-chain using a single CPU and a single GPU for any B. The second is to propose two strategies to improve the generation of a shortest B-chain using two (or more) GPUs. Using two GPUs, the experimental study shows that the first strategy improves the performance by about 20%, while the second strategy improves the performance by about 30 ∼ 35% in case of B = {+}. It is also possible to combine both strategies when we have at least four GPUs

A new approach to modeling the behavior of frozen soils

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordIn this paper a new approach is presented for modeling the behavior of frozen soils. A data-mining technique, Evolutionary Polynomial Regression (EPR), is used for modeling the thermo-mechanical behavior of frozen soils including the effects of confining pressure, strain rate and temperature. EPR enables to create explicit and well-structured equations representing the mechanical and thermal behavior of frozen soil using experimental data. A comprehensive set of triaxial tests were carried out on samples of a frozen soil and the data were used for training and verification of the EPR model. The developed EPR model was also used to simulate the entire stress-strain curve of triaxial tests, the data for which were not used during the training of the EPR model. The results of the EPR model predictions were compared with the actual data and it was shown that the proposed methodology can extract and reproduce the behavior of the frozen soil with a very high accuracy. It was also shown that the EPR model is able to accurately generalize the predictions to unseen cases. A sensitivity analysis revealed that the model developed from raw experimental data is able to extract and effectively represent the underlying mechanics of the behavior of frozen soils. The proposed methodology presents a unified approach to modeling of materials that can also help the user gain a deeper insight into the behavior of the materials. The main advantages of the proposed technique in modeling the complex behavior of frozen soil have been highlighted

Cybersecurity in Health Systems: Challenges, And Proposals

The new rise in network safety breaks in medical care organizations has put patients' security at a higher risk of being uncovered. In spite of this danger and the extra danger posed by such incidents to patients' safety, as well as functional and monetary dangers to medical care organizations, few studies have deliberately analysed the cyber security risks in medical care. To establish a strong starting point for medical services organizations and policymakers in better comprehension the intricacy of the issue of cyber security, this study investigates the significant sort of cyber security risks for health care organizations and makes sense of the roles of the four keys (cyber attackers, cyber defenders, developers, and end users) in cyber security. Finally, the paper studies a group of recommendations for the policymakers and health care organizations to reinforce cybersecurity in their organizations

In vitro studies on gum acacia and its potential as a prebiotic in an elderly population

Gum acacia (GA) is a soluble dietary fibre derived from acacia trees. It is widely used in African countries and in the Middle East as a traditional medicine. Recently, the consumption of GA has been related to potential health benefits in terms of its potential prebiotics properties, this may be particular relevant in elderly people. Elderly are experiencing negative changes in their gut microbiota and their immune system. Therefore, in this study GA was assessed in in vitro models, and resulted in increased Bifidobacterum spp., which can be important for a targeted population such as elderly. Further evaluation of GA looked at the potential to induce cytokines production with PBMC cells from elderly volunteers. Promising increases in IL-10 were observed. The bacteria able to utilise GA, whilst possessing anti-microbial potential were further studied using enrichment culture techniques. Here Lactobacillus spp. were isolated and shows antipathogenic activity against known pathogens. The antimicrobial activity was related to the lowering pH regards to organic acid production. Finally, further investigation to evaluate the probiotic bacteria and the associated synbiotic was evaluated in the presence of E. coli. within in vitro mixed batch cultures. The synbiotic combination led to increases lactobacilli and inhibition in C. histolyticum group, this effect was more apparent than with the GA, or probiotic alone treatments. Overall, the potential of GA as a prebiotic has been explored, furthermore, a possible synbiotic combination has been developed. These products could show great potential to an ageing population

Experimental implementation of thermal enhancement performance of air heat exchanger’s pipes utilizing unconventional turbulator

Heat exchangers are widely used in industry, however, raising their performance are important for the variety of applications. Consequently, efficiency improvement associated with low production cost is considered in this experimental work. The current study aims to enhance the rate of heat transfer in pipe-type heat exchangers experimentally by using a novel nozzle as a turbulator. The cross-sectional shape of the nozzle is hexagonal, and the diameter ratio DR is equal to 0.5. Constant heat flux was maintained in the vicinity of the section of the test tube, while the working fluid was pumped into the open system at six discrete Reynolds number values ranging from 6000 to 19500. To investigate the effect of distance among the pieces, three turbulators with different numbers were assigned and named as (N=4, 5 and 6). The results indicated an increase of 172 %, 194 % and 216 % of the heat transfer rate for cases 4, 5 and 6 respectively comparing to the benchmark tube. On the other hand, the friction factor values increased remarkably due to the inserting of turbulators by about of 722.9 % for N=4, 823.9 % for N=5 and 886.7 % for N=6 compared to a plain tube case. Moreover, it has been established that with the insertion of 6 pieces two enhancements was observed; heat transfer rate and thermal performance, where, thermal performance of all cases exceeds unity (maximum thermal performance of 1.62 has been obtained by inserting 6 pieces of hexagonal nozzles turbulators). A comparison with another types of vortex generators shows the gap between the turbulator and heated surface offers a solution for problems occurred in the pipes of heat exchanger. The study therefore suggests a wider practical implementation of the turbulator

Trace elements disturbance and Liver toxicity in Sudanese Fuel Stations Workers

Abstract: Workers in benzene stations are more susceptible to hepatotoxicity. This study was aimed to assess serum levels of trace elements and liver enzymes activity as indicator of hepatotoxicity in benzene station workers. In a matched case control study conducted in Khartoum State -Sudan during the period from October 2015 to January 2016. After signing written informed consent blood specimen was collected from 50 individual working in petrol station as case group and 20 healthy individuals not working in petrol station as control group aged from (20-50) years and serum levels of AST,ALT.GGT activity and Copper and Zink was measured using spectrophotometrical and atomic absorption methods. Data were collected using structural questionnaire. Data analysis was carried out by means of statistical package for social science (SPSS version 16). The mean level of Copper and Zinc was significantly decreased in comparison with control group (p < .05). There was no significant correlation of serum level of trace elements zinc and copper with duration, BMI, AST, ALT, and GGT activities. Working in petrol station is associated with decreased level of copper and Zink however the disturbance in these trace elements dose not correlated with abnormalities in liver enzymes

New Public Key Cryptosystem (First Version)

In this article, we propose a new public key cryptosystem, called \textbf{NAB}. The most important features of NAB are that its security strength is no easier than the security issues of the NTRU cryptosystem~\cite{Hoffstein96} and the encryption/decryption process is very fast compared to the previous public key cryptosystems RSA~\cite{Rivest78amethod}, Elgamal~\cite{ElGamal85}, NTRU~\cite{Hoffstein96}. Since the NTRU cryptosystem~\cite{Hoffstein96} is still not known to be breakable using quantum computers, NAB is also the same. In addition, the expansion of the ciphertext is barely greater than the plaintext and the ratio of the bit-size of the ciphertext to the bit-size of the plaintext can be reduced to just over one. We suggest that NAB is an alternative to RSA~\cite{Rivest78amethod}, Elgamal~\cite{ElGamal85} and NTRU~\cite{Hoffstein96} cryptosystems

Morning administration of 0.4 U/kg/day insulin glargine 300 U/mL provides less fluctuating 24-hour pharmacodynamics and more even pharmacokinetic profiles compared with insulin degludec 100 U/mL in type 1 diabetes

Abstract Aim To compare steady state pharmacodynamic and pharmacokinetic profiles of insulin glargine 300U/mL (Gla-300) with insulin degludec 100U/mL (Deg-100) in people with type 1 diabetes. Methods This single-centre, randomized, double-blind crossover euglycaemic clamp study included two parallel cohorts with fixed once-daily morning dose regimens. For both insulins participants received 0.4 ( n =24) or 0.6U/kg/day ( n =24), before breakfast, for 8 days prior to the clamp. The main endpoint was within-day variability (fluctuation) of the smoothed glucose infusion rate (GIR) over 24 hours (GIR-smFL 0–24 ). Results Gla-300 provided 20% less fluctuation of steady state glucose infusion rate profiles than Deg-100 over 24 hours at 0.4U/kg/day (GIR-smFL 0–24 treatment ratio 0.80 [90% confidence interval: 0.66 to 0.96], P =0.047), while at the dose of 0.6U/kg/day the difference between insulins was not statistically significant (treatment ratio 0.96 [0.83 to 1.11], P =0.603). Serum insulin concentrations appeared more evenly distributed with both dose levels of Gla-300 versus the same doses of Deg-100, as assessed by relative 6-hour fractions of the area under the curve within 24 hours. Both insulins provided exposure and activity until 30 hours (end of clamp). Conclusion Gla-300 provides less fluctuating steady state pharmacodynamic profiles (i.e. lower within-day variability) and more evenly distributed pharmacokinetic profiles, compared with Deg-100 in a once-daily morning dosing regimen of 0.4U/kg/day

Prevalence of cigarette smoking in Tehran: A household study

Objective: Cigarette smoking is a highly addictive behavior and nicotine dependence is a well known model for drug dependence. It also acts as a gateway drug for the use of other illicit substances. In 1999, Iran Ministry of health and the national research center carried out a study which revealed that 11.9 of Iranian population use cigarette. Methods: The present study is a cross-sectional household survey which was carried out in 2004.The target population of this study consisted of residents (age>15) of the sixth district of the municipality of Tehran. The sample was selected through multistage stratification and systematic randomization (n= 2705). Data was gathered using face-to-face interviews. Results: Our study showed that five hundred and forty (19.9) subjects reported regular use of cigarette sometimes in their life. 381 (14.1) reported that they were current smokers. The Prevalence of smoking and the mean number of cigarette smoked daily were lower in women compared to men. 74.1 of the smokers reported that they smoked their first cigarette before the age of 25. Only 7.8 reported that they started smoking after the age of 35. Conclusion: The self-reported lifelong prevalence and the prevalence of current smoking are much lower in Iran compared to many other Middle East countries. Moreover, according to the findings of this study, the number of attempts to quit smoking in Iran is lower than the reported rate in other countries of the region

Undiagnosed endometrial abnormalities in women with normal hysterosalpingography scheduled for IVF: prospective evaluation of three-dimensional transvaginal ultrasound versus office hysteroscopy

Objectives: To compare the diagnostic accuracy of three-dimensional transvaginal ultrasound (3D-US) to office hysteroscopy (OH) in the screening of uterine cavity with normal hysterosalpingography (HSG) findings for subtle endometrial abnormalities before in vitro-fertilization (IVF). Methods: A prospective cohort cost-modeling study was carried out in a University hospital. We included 120 infertile women with a normal uterine cavity on HSG scheduled for IVF. All cases were evaluated by 3D-US, and the results were compared with OH findings. Results: OH revealed cavitary endometrial lesions (CLs) in thirty-four women (28.3%). Endometrial polyps were the most common detected lesions (16, 47.1%). 3D-US had 88.2% sensitivity, 96.5% specificity, 90.9% positive predictive value, 95.4% negative predictive value, and 94.2% overall accuracy for CLs. The overall agreement between 3D-US and OH was near-perfect (κ=0.86, 95% CI=0.75-0.96). Irregular menstrual bleeds and prior endometrial procedures were significant predictors for CLs (aOR=24.96, 95% CI=2.71–230.04, P=0.005, aOR=9.16, 95% CI=2.13–39.3, P=0.002, respectively). A selective screening strategy discerning OH to women with these predictors and/or women with abnormal 2D-US would have an NPV of 92.8 % with substantial cost benefits. Conclusions: In the pre-IVF work up, 3D-US, a non-invasive imaging modality, seems to be nearly comparable to OH. Office hysteroscopy screening prioritizing women with abnormal 2D-US, irregular menstrual periods and/or prior endometrial traumatization could yield a satisfactory cost-effective approach for identifying endometrial lesions