Synthesis of some pyridyl and cyclohexyl substituted 1,2,4 triazole, 1,3,4-thiadiazole and 1,3,4-oxadiazole derivatives

New 1,2,4-triazoles (4a-c), 1,3,4-thiadiazoles (5a-c) and 1,3,4-oxadiazoles (6a-c) containing isomeric pyridyl and cyclohexyl were synthesized by intramolecular cyclization of 1,4-disubstituted thiosemicarbazides (3a-c) in alkaline media, acid and neutral condition respectively. The chemical structures of newly synthesized compounds were established with help of FT-IR, 1H-NMR and mass spectral data

Synthesis of some novel Schiff bases containing 1,2,4-triazole ring

4-Allyl-5-piridine-4-yl-4H-1,2,4-triazole-3-thiol was prepared under facile condition via the formation of 2-isonicotinoyl-N-allylhydrazinecarbothioamide. In addition, ethyl[(4-allyl-5-pyridine-4-yl-4H-1¸2¸4-triazole-3-yl)thio]acetate was synthesized via the reaction of 4-allyl-5-piridine-4-yl-4H-1,2,4-triazole-3-thiol with ethyl chloroacetate. 2-[(4-Allyl-5-pyridine-4-yl-4H-1,2,4-triazole-3-yl)thio]acetohydrazide obtained by using ethyl[(4-allyl-5-pyridine-4-yl-4H-1¸2¸4-triazole-3-yl)thio]acetate as a precursor by two steps, was converted to Schiff base derivatives, 6a-j. All synthesized compounds were characterized by elemental analyses, IR spectroscopy, 1H NMR and 13C NMR spectroscopy. The cis/trans conformers of E isomer were present in DMSO solution of compounds 6a-j

A novel public key crypto system based on semi-modules over quotient semi-rings

In A generalization of the original Diffie-Hellman key exchange in (ℤ/pℤ)* found a new depth when Miller and Koblitz suggested that such a protocol could be used with the group over an elliptic curve. Maze, Monico and Rosenthal extend such a generalization to the setting of a Semi-group action on a finite set, more precisely, linear actions of abelian semi-rings on semi-modules. In this paper, we extend such a generalization to the linear actions of quotient semi-rings on semi-modules. In fact, we show how the action of quotient semi-rings on a semi-module gives rise to a generalized Diffie-Hellman and ElGamal protocol. This leads naturally to a cryptographic protocol whose difficulty is based on the hardness of a particular control problem, namely the problem of steering the state of some dynamical system from an initial vector to some final location

On DPA-Resistive Implementation of FSR-based Stream Ciphers using SABL Logic Styles

The threat of DPA attacks is of crucial importance when designing cryptographic hardware. This contribution discusses the DPA-resistant implementation of two eSTREAM finalists using SABL logic styles. Particularly, two Feedback Shift Register (FSR) based stream ciphers, Grain v.1 and Trivium are designed in both BSim3 130nm and typical 350nm technologies and simulated by HSpice software. Circuit simulations and statistical power analysis show that DPA resistivity of SABL implementation of both stream ciphers has a major improvement. The paper presents the tradeoffs involved in the circuit design and the design for performance issues

Mapping 123 million neonatal, infant and child deaths between 2000 and 2017

Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations

Synthesis of Novel Bibrachial Lariat Ethers (BiBLEs) Containing

ABSTRACT A practical and regioselective method for the synthesis of cis-diastereomers of bibrachial lariat ethers (BiBLEs) bearing ester and amide groups is reported. The novel bibrachial lariat ethers (BiBLEs) 3a-d with neutral side chains were prepared by reaction of the corresponding aza-crown macrocycles 1a-b with ethyl chloroacetate and chloroacetamide

Three component, one-pot synthesis of amidoalkyl naphthols using polyphosphate ester under solvent-free conditions

Amidoalkyl naphthols are synthesized via a simple, one-pot, three-component reaction between aldehydes, 2-naphthol and amides or ureas using polyphosphate ester (PPE) as a reaction mediator under solvent-free conditions in good to excellent yields. High yields, short reaction time, easy work-up, elimination of solvents and toxic catalysts are the advantages of this procedure

A Novel Public Key Crypto system Based on Semi-modules over Quotient Semi-rings

Abstract: In A generalization of the original Diffie-Hellman key exchange in (ℤ/pℤ) * found a new depth when Miller and Koblitz suggested that such a protocol could be used with the group over an elliptic curve. Maze, Monico and Rosenthal extend such a generalization to the setting of a Semi-group action on a finite set, more precisely, linear actions of abelian semi-rings on semimodules. In this paper, we extend such a generalization to the linear actions of quotient semi-rings on semi-modules. In fact, we show how the action of quotient semi-rings on a semi-module gives rise to a generalized Diffie-Hellman and ElGamal protocol. This leads naturally to a cryptographic protocol whose difficulty is based on the hardness of a particular control problem, namely the problem of steering the state of some dynamical system from an initial vector to some final location. Keywords: Public key cryptography, Diffie-Helman protocol, One-way trapdoor functions, Semi group actions, Quotient semi-ring

Relationship between EFL Learners’ Autonomy and Speaking Strategies They Use in Conversation Classes

The present study was conducted at Parsayan Language Institute in Isfahan, Iran. The students in pre- intermediate and intermediate classes were examined to investigate the relationship between degrees of learner autonomy, use of strategies for coping with speaking problems and the learners’ success in their speaking classes. To determine the degree of correlation among degree of learner autonomy, use of strategies for coping with speaking problems, and success in speaking classes, a validated questionnaire was distributed among 50 participants. The participants were required to self-report the strategies they use when they have problems during speaking English and to report their degree of learner autonomy as an English language learner by choosing one of the items on the questionnaire. The analysis of the obtained results showed that learners with low speaking grades were weaker in comparison with learners with high speaking grades during the use of strategies for coping with speaking problems on the whole. Similarly, learners with low speaking grades reported themselves as less autonomous when compared to high proficiency learners of English, although the difference was not significant between the group of learners in average speaking grade and high grade level. The first desirable endpoint should be some kind of modification on the curriculum of language teaching in terms of development of learner autonomy. More chances for developing autonomy should be offered to the students so that they would get used to it and be more successful in communication skills.Keywords: Learner Autonomy, Strategies for Coping with Speaking Problems in English, Speaking Classe

Relationship between EFL Learners’ Autonomy and Speaking Strategies They Use in Conversation Classes

The present study was conducted at Parsayan Language Institute in Isfahan, Iran. The students in pre- intermediate and intermediate classes were examined to investigate the relationship between degrees of learner autonomy, use of strategies for coping with speaking problems and the learners’ success in their speaking classes. To determine the degree of correlation among degree of learner autonomy, use of strategies for coping with speaking problems, and success in speaking classes, a validated questionnaire was distributed among 50 participants. The participants were required to self-report the strategies they use when they have problems during speaking English and to report their degree of learner autonomy as an English language learner by choosing one of the items on the questionnaire. The analysis of the obtained results showed that learners with low speaking grades were weaker in comparison with learners with high speaking grades during the use of strategies for coping with speaking problems on the whole. Similarly, learners with low speaking grades reported themselves as less autonomous when compared to high proficiency learners of English, although the difference was not significant between the group of learners in average speaking grade and high grade level. The first desirable endpoint should be some kind of modification on the curriculum of language teaching in terms of development of learner autonomy. More chances for developing autonomy should be offered to the students so that they would get used to it and be more successful in communication skills.Keywords: Learner Autonomy, Strategies for Coping with Speaking Problems in English, Speaking Classe