2,054 research outputs found

    An Elliptic Curve-based Signcryption Scheme with Forward Secrecy

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    An elliptic curve-based signcryption scheme is introduced in this paper that effectively combines the functionalities of digital signature and encryption, and decreases the computational costs and communication overheads in comparison with the traditional signature-then-encryption schemes. It simultaneously provides the attributes of message confidentiality, authentication, integrity, unforgeability, non-repudiation, public verifiability, and forward secrecy of message confidentiality. Since it is based on elliptic curves and can use any fast and secure symmetric algorithm for encrypting messages, it has great advantages to be used for security establishments in store-and-forward applications and when dealing with resource-constrained devices.Comment: 13 Pages, 5 Figures, 2 Table

    Designing a range modulator wheel to spread-out the Bragg peak for a passive proton therapy facility

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    In proton beam therapy, a Spread-Out Bragg peak (SOBP) is used to establish a uniform dose distribution in the target volume. In order to create a SOBP, several Bragg peaks of different ranges, corresponding to different entrance energies, with certain intensities (weights) should be combined each other. In a passive beam scattering system, the beam is usually extracted from a cyclotron at a constant energy throughout a treatment. Therefore, a SOBP is produced by a range modulator wheel, which is basically a rotating wheel with steps of variable thicknesses, or by using the ridge filters. In this study, we used the Geant4 toolkit to simulate a typical passive scattering beam line. In particular, the CATANA transport beam line of INFN Laboratori Nazionali del Sud (LNS) in Catania has been reproduced in this work. Some initial properties of the entrance beam have been checked by benchmarking simulations with experimental data. A class dedicated to the simulation of the wheel modulators has been implemented. It has been designed in order to be easily modified for simulating any desired modulator wheel and, hence, any suitable beam modulation. By using some auxiliary range-shifters, a set of pristine Bragg peaks was obtained from the simulations. A mathematical algorithm was developed, using the simulated pristine dose profiles as its input, to calculate the weight of each pristine peak, reproduce the SOBP, and finally generate a flat dose distribution. Therefore, once the designed modulator has been realized, it has been tested at CATANA facility, comparing the experimental data with the simulation results

    The burden of schizophrenia in the Middle East and North Africa region, 1990–2019

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    Schizophrenia ranks as the third-most common cause of disability among mental disorders globally. This study presents findings on the prevalence, incidence and years lived with disability (YLDs) as a result of schizophrenia in the Middle East and North Africa (MENA), stratified by age, sex and sociodemographic index (SDI). We collected publicly accessible data from the Global Burden of Disease (GBD) study 2019. This study reports the burden of schizophrenia, from 1990 to 2019, for the 21 countries that comprise MENA. In 2019, MENA exhibited an age-standardised point prevalence of 248.2, an incidence rate of 14.7 and an YLD rate of 158.7 per 100,000, which have not changed substantially between 1990 and 2019. In 2019, the age-standardised YLD rate was highest in Qatar and lowest in Afghanistan. No MENA countries demonstrated noteworthy changes in the burden of schizophrenia from 1990 to 2019. Furthermore, in 2019, the highest number of prevalent cases and the point prevalence were observed among those aged 35–39, with a higher prevalence among males in almost all age categories. Additionally, in 2019, the age-standardised YLD rates in MENA were below the worldwide average. Finally, there was a positive correlation between the burden of schizophrenia and the SDI from 1990 to 2019. The disease burden of schizophrenia has remained relatively stable over the past thirty years. Nevertheless, as the regional life-expectancy continues to increase, the burden of schizophrenia is also expected to rise. Therefore, early planning for the increase in the burden of the disease is urgently needed in the region

    Burden of diseases and injuries attributable to alcohol consumption in the Middle East and North Africa region, 1990–2019

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    Alcohol consumption is associated with a number of diseases and injuries, including cardiovascular diseases, cancers, mental and neurological disorders, as well as transport-related injuries. This article reports the alcohol-attributable burden of diseases and injuries at the regional and national levels in the Middle East and North Africa (MENA) region between 1990 and 2019, by sex, age, underlying cause, and Socio-demographic Index (SDI). The regional deaths and disability-adjusted life-years (DALYs) attributable to alcohol consumption were reported for the MENA region, between 1990 and 2019, using the methodological framework and analytical strategies adopted by the Global Burden of Disease (GBD) study 2019. The estimates were all reported as counts, population-attributable fractions, and age-standardised rates per 100,000 population, along with their corresponding 95% uncertainty intervals (UIs). Also, the average annual percentage changes were used to represent the trends of age-standardised rates. In 2019, there were an estimated 22.0 thousand deaths (95% UI: 16.1–29.4) and 1.1 million DALYs (0.8–1.3) attributable to alcohol consumption in the MENA region. The number of DALYs attributable to alcohol consumption were much higher in men (878.0 thousand, 691.4–1104.8) than among women (181.8, 138.6–232.0). The overall age-standardised death and DALY rates attributable to alcohol consumption decreased by 34.5% (13.2–48.3) and 31.9% (16.9–42.5), respectively, over the study period. Egypt (10.1 [5.7–16.6]) and Kuwait (1.1 [0.8–1.5]) had the highest and lowest age-standardised death rates attributable to alcohol consumption, respectively. In 2019, the number of deaths and DALYs in the MENA region were highest in those aged 60–64 and 50–54 years, respectively. A negative association was observed between a country’s SDI and their corresponding age-standardised DALY rates over the period 1990 to 2019. Digestive diseases were the main contributor to the alcohol-attributable burden. Over 1990–2019, the regional deaths and DALYs of diseases and injuries attributable to alcohol consumption decreased with AAPC of − 1.45 (− 1.78 to − 1.12) and − 1.31 (− 1.46 to − 1.15), respectively. The death and DALY rates attributable to alcohol consumption in the MENA region have decreased over the past three decades. Further decreases can be facilitated by implementing country-level policies and increasing public awareness

    Anticoagulant potential and total phenolic content of six species of the genus Ficus from Azad Kashmir, Pakistan

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    Purpose: To investigate the total phenolic and flavonoid contents of Ficus benghalensis, Ficus elasticaa, Ficus palmata, Ficus religiosa, Ficus semicordata and Ficus auriculata, and to determine their anticoagulant potential. Methods: Crude methanol extracts were prepared from the plant leaves, and fractionated using liquidliquid partition with n-hexane, chloroform and ethyl acetate. The total flavonoid and total phenolic contents of the extracts and their fractions were determined. The anticoagulant potential of the six Ficus species were evaluated in healthy human plasma, using activated partial thromboplastin time (APTT) and prothrombin time (PT) methods. Results: Phytochemical analysis showed the presence of considerable amounts of flavonoids ranging from 5.3 ± 0.7 to 11.8 ± 0.3 mg rutin equivalents (RE)/g, and phenolic compounds ranging from 8.0 ± 0.7 to 86.5 ± 1.5 mg gallic acid equivalents (GAE)/g in each fraction of the six species. Results from in vitro anticoagulant potential assays showed significant anticoagulant properties, with prothrombin time (PT) ranging from 17.7 ± 0.7 to 26.7 ± 2.2 s, and activated partial thromboplastin time (APTT) varying from 47.7 ± 3.3 to 72.3 ± 5.4 s. Conclusion: The results indicate that F. semicordata and F. Religiosa have higher anticoagulant potential than the other Ficus species studied

    Climate change impact on bioclimatic deficiency, using microLEIS DSS in Ahar soils, Iran

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    Regional impact studies of the future climate change effects are necessary because projected changes in meteorological variables differ from one region to another, and different climate systems can react in varied ways to the same changes. In this study, the effects of climate change on bioclimatic deficiency were compared in two cultivation methods (irrigated and rainfed) in a semi-arid region, Ahar (East Azarbaijan, IRAN). The agricultural land uses selected for evaluation were wheat (Triticum aestivum), alfalfa (Medicago sativa), sugar beet (Beta vulgaris), potato (Solanum tuberosum), and maize (Zea mays). In this way, Terraza model included in the land evaluation decision support system, called MicroLEIS DSS, was used. Terraza gives a quantitative prediction of a site bioclimatic deficiency. Soil morphological and analytical data were obtained from 44 sampling points based on a grid survey. Agro-climatic data, referred to temperature and precipitation, were collected from weather stations located in Ahar region, which benefits from more than 20 consecutive years of weather data. A future scenario of climate change was calculated according to the Intergovernmental Panel on Climate Change (IPCC) on regions of Asia under scenario A1FI (highest future emission) for 2080s. Although, increasing of precipitation being available by climate change in the future scenario, humidity index will be reduced because of high temperature. The results showed that climate change is likely to cause severe water stress in irrigated cultivation of alfalfa, sugar beet, potato, and maize, the use of irrigation methods being essential to maintain agricultural productivity. Although irrigation is indicated as very important in this regime of semi-arid agriculture, cultivation of rainfed wheat can be possible instead of the irrigated one. Also, it is revealed that climate perturbation effects on rainfed conditions are more serious than those on the irrigated conditions in the area.The authors wish to thank Tabriz University for funding this research work, a dissertation of Ph. D. program undertaken by Farzin Shahbazi. They also thank Consejo Superior de Investigaciones Científicas (CSIC), Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), Sevilla, Spain for their sincere cooperation during the candidate’ s sabbatical studies.Peer Reviewe
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