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We report a green and efficient method for the synthesis of 4-arylidene-1-(4-phenylselenazol-2-yl)-3-methyl-1H-pyrazole-5(4H)-ones from the condensation of phenacyl bromide, selenosemicarbazide with ethyl acetoacetate and aryl aldehyde in acetic acid using sodium acetate as a base. [ABSTRACT FROM AUTHOR]

In this paper, an event-triggered dynamic surface controller is proposed for strict-feedback nonlinear networked systems with mismatched uncertainties. Towards this aim and first of all, an event-based dynamic surface control law is designed. Then, the closed-loop error dynamics is derived and rewritten as a linear dynamics with nonlinear perturbation terms. Next, these terms are classified into vanishing and nonvanishing perturbations. Finally, by imposing some constraints on the nonvanishing terms, an event-triggering mechanism is constructed. By formulating the imposed constraints in the form of linear matrix inequalities (LMIs) and using the ultimate boundedness theory, the ultimate error boundedness and quadratic tracking objectives are addressed in the framework of convex optimisation. The absence of the Zeno behaviour, which is an important feature of any event-triggered methodology, is also proven. The validity of the theoretical results is illustrated by applying the proposed method to a remotely operated underwater vehicle in a simulation study as well as an experimental implementation on a magnetic levitation system. [ABSTRACT FROM AUTHOR]

The mechanical qualities of single – and multi-layer CH3NH3XI3 (X = Pb, Sn, Mn) perovskite structures have been computed using the LAMMPS programme via the molecular dynamics' method. The LAMMPS analysis code is the keystone for computing mechanical characteristics in simulations. The stress–strain curves of the simulated atomic structures are offered for tests in the X and Y directions. The stress–strain curves were significantly computed by employing the loading technique and the deform command during the computational tests. Mechanical data was retrieved by inducing deformation in the simulated structures. The stress–strain curves for the single – (SL) and the multi-layer (ML) CH3NH3XI3 at various temperature and pressure values in the X and Y directions were also produced and compared, after applying a maximum stress (ultimate strength) using a load. Molecular dynamics (MD) simulations using LAMMPS software showed that layered perovskite materials possess high flexibility compared to the non-layered perovskite materials, which is essential in perovskite solar cells. The studied atomic structures thus provided the significant mechanical properties for designing proficient perovskite solar cells via the MD simulation. [ABSTRACT FROM AUTHOR]

The new compounds 6-methyl-8-morpholino-2H pyrimido[5',4':5,6][1,4]thiazino[3,2e][1,2,4]triazin-3(5H)-one (3a) and 6-methyl-8-(piperidin-1-yl)-2Hpyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazin-3(5H)-one (3b) were obtained from cyclocondensation of 6-bromo-1,2,4-triazine-3,5(2H,4H)-dione (1) with appropriate 5-amino-6methylpyrimidine-4-thiol (2a, b) in dimethylformamide and in the presence of potassium carbonate under reflux. Reaction of compounds (3a, b) with phosphorous oxychloride gave 4-(3-chloro-6-methyl-5H-pyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazin-8-yl)morpholine (4a) and 3-chloro-6-methyl-8-(piperidin-1-yl)-5H-pyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazine (4b). Nucleophilic substitution of chlorine atom of compounds (4a, b) with typical secondary amines in DMF and K2CO3 produced the new derivatives of the 3,8-disubstituted-5H-pyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazine ring systems (5a–f). All the synthesized products were characterized and confirmed by their spectroscopic and microanalytical data. [ABSTRACT FROM AUTHOR]

Family caregivers of people with substance abuse are exposed to psychological problems that diminish their life quality and satisfaction. The purpose of this study was to diagnose the efficacy of quality-of-life intervention on stress and life satisfaction of family caregivers of individuals with substance use problem. This is a randomized controlled trial conducted on 80 family caregivers of individuals with substance use problem in the process of withdrawal who were referred to a psychiatric center in southeastern Iran (2018). The intervention group received seven sessions of quality-of-life group counseling every other day based on predetermined content. Twelve weeks post-intervention, data were collected from the control and intervention groups using the Depression Anxiety and Stress Scales (DASS-21) and the Satisfaction with Life Scale (SWLS). The results were analyzed through statistical tests. After group counseling based on quality of life, the mean stress score in the family caregivers of the intervention group (11.50 ± 4.36) was significantly lower than in those of the control group (14.67 ± 4.93) (p = 0.003). Also, in the posttest, the mean score of life satisfaction in the intervention group (24.75 ± 4.28) was significantly higher than that of the control group (19.57 ± 7.33) (p = 0.001). Group counseling based on quality of life exerted a significantly positive impact on reducing the severity of stress and improving life satisfaction among family caregivers of individuals with substance use problem. Therefore, it is highly recommended that healthcare service providers incorporate this counseling approach in substance use withdrawal programs so as to increase the well-being and mental health of family caregivers. [ABSTRACT FROM AUTHOR]

The 1:1 imine intermediate generated by the addition of primary amine to chloroacetone derivatives is trapped byN-isocyaniminotriphenylphosphorane in the presence of phenylacetylenecarboxylic acid, leading to the formation of the corresponding iminophosphorane intermediate. Disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediate. The reactions were completed in neutral conditions at room temperature. The disubstituted 1,3,4-oxadiazole derivatives were prepared in excellent yields. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®to view the free supplemental file. [ABSTRACT FROM AUTHOR]