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Mogos G.,School of Technology of Chimborazo, Riobamba
2015 International Symposium on Networks, Computers and Communications, ISNCC 2015 | Year: 2015

The main goals of cryptography are for a sender and a receiver to be able to communicate in a way that is unintelligible to third parties, and for the authentication of messages to prove that they were not altered in transit. Both of these goals can be accomplished with provable security if sender and receiver are in possession of shared, the secret key. This paper presents a software-prototype of the Bechmann-Pasquinucci and Peres protocol for qutrits, on two cases: with and without cyber-attack (the Intercept-Resend attack). Presence of the enemy is determined by calculating the errors obtained at the end of transmission through quantum channel. The method Quantum Trit Error Rate (QTER) for detecting enemy can be applied to the majority key distribution systems, each system having its own acceptable error rate. © 2015 IEEE. Source


Rationale: Osteoporosis is a cause for pathological fractures and loss of autonomy and validism in the postmenopausal woman. Identification of risk factors might serve for preventing the appearance of this co-morbidity.Objectives: To determine the association between loss of bone mineral density (BMD) and selected demographic, clinical and anthropometric features in the postmenopausal woman that can be assumed as risk factors of osteoporosis.Study design: Non-experimental, cross-sectional, analytical.Study serie: 53 women with ages ≥ 60 años assisted at the “San Juan” Specialities Hospital in Riobamba (Province of Chimborazo, Republic of Ecuador). Materials and methods: BMD was determined in 2 regions of interest (lumbar spine | femur) by means of DEXA (DPX-L, Lunar Technologies, USA). Loss of BMD was established with “t”-scores < -1.0 standard deviations. Amount and quality of dietetic Calcium intakes were estimated by means of pCa score that takes into account frequency of consumption of foods regarded as sources of calcium and mineral bioavailability. Nature and strength of association between loss of BMD, on one hand, and presuntive risk factors of osteoporosis and state of dietetic calcium intake, on the other, were assessed.Results: Loss of BMD was dependent upon region of interest: Femur: Osteoporosis: 13.2% + Osteopenia: 50.9%; Lumbar spine: Osteoporosis: 49.1% + Osteopenia: 37.7%. Highest intakes of dietetic calcium concentrated among Milk and dairy products (pCa = 26.56), Meat, poultry, fish, seafood and eggs (pCa = 6.51), Beans and others legumes (soy included) (pCa = 2.85); and Vegetables (pCa = 2.54); respectively. DMO “t” score associated with woman’s age, family history of bone fractures, Body Mass Index (BMI), and body fat (estimated by means of DEXA). Dietetic calcium intakes were independent of presumptive risk factors of osteoporosis and DMO “t” score in the region of interest. Odds-ratios for variables univariately associated with BMD were as follows: Age: OR = 2.09 (p < 0.05); BMI: OR = 0.278 (p = 0.059); and Body fat: OR = 0.553 (p > 0.05); respectively.Conclusions: Loss of BMD is significantly associated with female aging, and an increased presence of body fat. Family history of bone fractures might serve for identifying post-menopausal women at increased risk of loss of BMD. Further research is required in order to establish the role of physical exercise and better intakes of dietetic calcium as protective factors against loss of BMD. © 2014 Grupo Aula Medica S.A. All rights reserved. Source


Mogos G.,School of Technology of Chimborazo, Riobamba
2015 14th RoEduNet International Conference - Networking in Education and Research, RoEduNet NER 2015 - Proceedings | Year: 2015

The practical implementation of quantum information technologies requires, for the most part, highly advanced and currently experimental procedures. One exception is quantum cryptography, or quantum key distribution, which has been successfully demonstrated in many laboratories and has reached an advanced level of development. The purpose of this paper is to present comparative studies regarding the percentages of quantum errors which appear when obtaining the cryptographic keys in the case of two quantum key distribution protocols: Chen et al. (four-state quantum key distribution scheme) and Bruβ (six-state quantum key distribution scheme). Were followed the variation of the percentage of errors in the case of these symmetrical protocols in two situations: the absence and the presence of cyber-attacks (Intercept-Resend attack), and, analyze the degree of security of the protocols. © 2015 IEEE. Source


Mogos G.,School of Technology of Chimborazo, Riobamba
Procedia Computer Science | Year: 2015

In this paper, we propose a software implementation of Quantum Key Distribution scheme using twelve orthogonal states in a four-state system. With the twelve states, the Sender can encode two bits classical information in one particle, and distribute her secret key to the Receiver. This study explores quantum alternatives to traditional key distribution protocols, and involves implementations of quantum key distribution protocol on two cases: with and without cyber-attacks (the Intercept-Resend attack). © 2015 The Authors. Source


Saeteros Hernandez R.C.,School of Technology of Chimborazo, Riobamba
Revista Cubana de Salud Publica | Year: 2013

Introduction: one of the keys to healthy and pleasurable sexuality and to full satisfaction in intimate relationships is to have proper sexual education. Objective: to identify the sexuality experiences of university students. Methods: a cross-sectional descriptive study was conducted during 2009 - 2010 at Higher Polytechnic School of Chimborazo in Ecuador. A survey was designed to find out the general features, behaviors, knowledge, opinions and information sources in sexuality. Data were collected using a web-based survey system in a probabilistic sample stratified by faculty, focus groups and through answers of students to questions and concerns on the topic. Results: the student population was young, most of them were sexually active and unmarried; differences in sexual behavior predominated according to sex and male students were more likely to facing sexual risk. In terms of knowledge, they had difficulties in understanding the meaning of sexuality; they did not know the sexual and reproductive rights and effective measures to prevent sexually transmitted infections. In fact, 17.86 % had never used condom in their sexual intercourses. Their opinions showed that the traditional way of thinking about sexual issues was still there. Their main source of information was their friends and the most preferred topics were related to erotism, sex pleasure, reproduction and prevention of sexually transmitted infections. Conclusions: sexual education is poor or nonexistent among young university students and their families, the university and the various socializing spaces. It does not appear to be one of the formative cores at university education. Source

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