Abstract Friction stir welding (FSW) is considered one of the most prominent methods for joining ductile materials. In this process, joining occurs in a plastic state without melting the base metals. Therefore, there is a lack of solidification cracking and shrinking of friction stir weld joints. Although, the improper stirring action of the FSW tool reduces the frictional heat input and flow of plasticized material, which deteriorates the weld joint quality. Insufficient and excessive heat input both results in the formation of weld flaws. The FSW is assisted with various new supporting tools to reduce weld flaws. The main objective of this paper is to provide collective information regarding supportive tool systems employed with FSW for the mitigation or elimination of weld flaws. FSW tool systems such as non-rotational shoulder assisted FSW, counter-rotating twin tool, reverse dual rotation, self-reacting tool, and in-situ rolling tool, and their impact on the weld joint formation is presented in this article. This paper also presented an overview of the remarkable effect of optimizing the FSW process parameters and the influence of tool pin profiles on weld joint quality. From this review, it is concluded that various FSW supporting tool systems significantly reduce the weld flaws.

Abstract. A series of novel pyridine-connected piperidine derivatives (2a-g) and pyridine-connected 2H-thiopyran derivatives (4a-g) were synthesized and evaluated for larvicidal, nematicidal, and antimicrobial activities. Compound 4e exhibited larvicidal activity against second instar larvae with an LD50 value of 0.8 μg/mL. In addition, 4e was most effective against root knot nematode Meloidogyne javanica , with an LD50 value of 3.2 μg/mL. Compounds 2e (MIC: 4 μg/mL) and 2d (MIC: 4 μg/mL) exhibited high antibacterial activity against Klebsiella pneumonia, and Escherichia coli, respectively. Compounds 4b (MIC: 0.25 μg/mL) and 4f (MIC: 2 μg/mL) showed high antifungal activity against Candida albicans and Microsporum audouinii, respectively. Therefore, overall activity profiles envisages that compounds 2e, 2d, 4e, 4b, and 4f could be employed for the development of new classes of drugs with larvicidal, nematicidal, and antimicrobial activities.

Resumen. Se sintetizaron una serie de nuevos derivados de piperidina conectados con piridina (2a-g) y derivados de 2H-tiopirano conectados con piridina (4a-g) para evaluar las actividades larvicidas, nematicidas y antimicrobianas. El compuesto 4e exhibió actividad larvicida contra larvas de segundo estadio con un valor de LD50 de 0.8 μg / mL. Además, 4e fue más efectivo contra el nematodo de nudo de la raíz Meloidogyne javanica, con un valor de LD50 de 3.2 μg / mL. Los compuestos 2e (MIC: 4 μg / ml) y 2d (MIC: 4 μg / ml) mostraron una alta actividad antibacteriana contra la neumonía de Klebsiella y Escherichia coli, respectivamente. Los compuestos 4b (MIC: 0.25 μg / ml) y 4f (MIC: 2 μg / ml) mostraron una alta actividad antifúngica contra Candida albicans y Microsporum audouinii, respectivamente. Por lo tanto, los perfiles de actividad general prevén que los compuestos 2e, 2d, 4e, 4b y 4f podrían emplearse para el desarrollo de nuevas clases de fármacos con actividades larvicidas, nematicidas y antimicrobianas.

Abstract This paper deals with fractional optimal control for a class of semilinear stochastic equation in Hilbert space setting. To ensure the existence and uniqueness of mild solution, a set of sufficient conditions is constructed. The existence of fractional optimal control for semilinear stochastic system is also discussed. Finally, an example is included to show the applications of the developed theory.

Resumen Este artículo estudia el control óptimo fraccional para una clase de ecuaciones estocásticas semilineales en un contexto de espacios de Hilbert. Para asegurar la existencia y la unicidad de soluciones blandas, construimos un conjunto de condiciones suficientes. La existencia del control óptimo fraccional para sistemas estocásticos semilineales también es discutido. Finalmente, incluimos un ejemplo para mostrar la aplicabilidad de la teoría desarrollada

Here we describe pyrrole derivatives with potent antibacterial and antifungal activity. A new series of pyrrole 3a-e derivatives were synthesized using standard amination reactions. All the compounds presented here were obtained with high yields and under easy experimental conditions. Synthesized compounds were characterized by IR, ¹H NMR, 13C NMR, mass spectra and mass spectral fragmentation. Synthesized compounds were screened against E. coli and S. aureus for antibacterial activity, as well as against A. niger and C. albicans for antifungal activity. We were able to obtain compounds with higher or equal potency to the reference compounds (Ciprofloxacin and Clotrimazole). Our data shows that a 4-hydroxyphenyl ring in our most potent compound seems to be responsible for antifungal activity against C. albicans. Incorporation of a 4-hydroxyphenyl ring as a pharmacophoric feature against C. albicans is a promising prospect.

Se describe la síntesis de una nueva serie de derivados pirrólicos con potente actividad antibacterial y antifúngica. La serie de compuestos 3a-e se sintetizó empleando reacciones de afinación estándar. Todos los compuestos preparados se obtuvieron en elevados rendimientos y bajo fáciles condiciones experimentales. Estos compuestos se caracterizaron por IR, RMN ¹H, RMN 13C, y su estudio de fragmentación en espectrometría de masas. Los compuestos sintetizados se evaluaron en su actividad antibacterial contra E. coli y S. aureus, y en su actividad antifúngica contra A. niger y C. albicans. Se lograron obtener compuestos con una potencia mayor o igual a los compuestos de referencia: ciprofloxacina y clotrimazol. Los datos muestran que el anillo 4-hidroxifenilo en el compuesto más activo parece ser el grupo farmacóforo responsable de la actividad antifúngica contra C. albicans.

O objetivo da investigação é avaliar uma nanoemulsão isotrópica termodinamicamente estável para a administração transdérmica da glicirrizina (GZ), com concentrações mínimas de tensoativo e co-tensoativo (Smix), que poderiam melhorar a sua solubilidade, a permeação e a estabilidade. Os diagramas pseudo-ternários de fase foram desenvolvidos e diversas nanoemulsões foram preparadas com óleo de soja como óleo, Span 80, Brij 35 como tensoativos e álcool isopropílico como co-tensoativo. As nanoemulsões que passaram por testes de estabilidade termodinâmica foram caracterizadas por pH, viscosidade, tamanho de gota e microscopia eletrônica de transmissão. A capacidade transdérmica da glicirrizina em passar através da pele de cadáver humano foi determinada por células de difusão de Franz. O perfil in vitro de permeação cutânea da formulação otimizada (NE2) foi comparada com a de gel convencional. Observou-se aumento significativo nos parâmetros de permeabilidade, como fluxo de equilíbrio (JSS) e coeficiente de permeabilidade (Kp) na formulação otimizado (NE2), que consistiu de 1% wt/wt de monoglicirrizinato de amônio (MAG), 32,4% de Span 80, 3,7% de Brij 35, 10% de álcool isopropílico, 46,5% de óleo de soja e 6,4% de água destilada. Não se observou irritação óbvia da pele para as nanoemulsões estudadas (NE2) ou de gel. Os resultados indicaram que nanoemulsões são promissores veículos para a administração transdérmica de glicirrizina através da pele de cadáveres humanos, sem o uso adicional de promotor de permeação, porque excipientes de nanoemulsões atuam como promotores de permeação.

The present investigation aims to evaluate an isotropic and thermodynamically stable nanoemulsion formulation for transdermal delivery of glycyrrhizin (GZ), with minimum surfactant and cosurfactant (Smix) concentrations that could improve its solubility, permeation enhancement, and stability. Pseudo-ternary phase diagrams were developed and various nanoemulsion formulations were prepared using soyabean oil as oil, Span 80, Brij 35 as a surfactant and isopropyl alcohol as a cosurfactant. Nanoemulsion formulations that passed the thermodynamic stability tests were characterized for pH, viscosity and droplet size using a transmission electron microscopy. The transdermal ability of glycyrrhizin through human cadaver skin was determined using Franz diffusion cells. The in vitro skin permeation profile of the optimized nanoemulsion formulation (NE2) was compared to that of conventional gel. A significant increase in permeability parameters such as steady-state flux (Jss) and permeability coefficient (Kp) was observed in the optimized nanoemulsion formulation (NE2), which consisted of 1% wt/wt of mono ammonium glycyrrhizinate (MAG), 32.4% Span 80, 3.7% Brij 35, 10% isopropyl alcohol, 46.5% soyabean oil and 6.4% distilled water. No obvious skin irritation was observed for the studied nanoemulsion formulation (NE2) or the gel. The results indicated that nanoemulsions are promising vehicles for transdermal delivery of glycyrrhizin through human cadaver skin, without the use of additional permeation enhancers, because excipients of nanoemulsions act as permeation enhancers themselves.

Naphthalene biodegradation was studied using the bacterial strain Pseudomonas putida S2. Three medium variables out of seven medium components were selected under Plakett-Burman (PB) design as having significant response on naphthalene biodegradation. These variables were citric acid (additional carbon sources), ammonium sulfate and sodium chloride. The levels of these three variables were optimized by the application of genetic algorithm (GA) based response surface methodology (RSM) in terms of maximum biodegradation efficiency. The maximum biodegradation efficiency of 55.51% was observed at concentrations of 1.0 g L-1, 1.0 g L-1, and 0.7g L-1 for citric acid, ammonium sulfate and sodium chloride, respectively. In addition, the interactive effects of significant medium variables were analyzed using three dimensional surface plots simulated by network output in terms of maximum fitness function.

The alcoholic extracts of leaves, latex and fruit from the Calotropis procera and Calotropis gigantea are tested for corrosion inhibition in basic solution by mass loss method and thermometric method. In the present investigation the extract reduces the corrosion rate of mild steel in basic solution. The inhibition efficiency increases as the extract concentration is increased. The alcoholic extract of Calotropis is found effective corrosion inhibitor in basic media and give up to 80.89% efficiency.