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PAN/phenolic-based carbon/carbon composites are finding more and more use, and becoming more and more important for space/aviation industries, and general structural applications. The primary constituents of these materials are fragile, and cracking occurs through random failures caused by imperfectionsinduced random failures. The strength of a fragile material follows Weibull distribution. The variation of the flexural strengths has been modeled using Weibull distribution. In order to compute m and σu, first, the values of σi were ordered from the smallest to the largest, and then applying linear regression to these values. From the linear regression, the Weibull modulus and the characteristic strength were estimated. The CFRP composites show maximum flexural strength which decreases during the pyrolysis at the temperature of 1000 0C. The reduced flexural strength can be related to void defects. These defects probably act as a source of fractures during loading. The failure probabilities for CFRP and C/C composites are 0.55 and 0.78, respectively, and these values 334 and 92 MPa, and 29 and 10.2 GPa for mean flexural strength and flexural modulus, respectively, would be quite useful for understanding the fiber-matrix interfacial bonding properties, which have a strong influence on the mechanical properties of these composites.

Adolescents frequently engage in risky behaviours such as binge drinking. Binge drinking, in turn, perturbs neurodevelopment reinforcing reward seeking behaviour in adulthood. Current animal models are limited in their portrayal of this behaviour and the assessment of neuroimmune involvement (specifically the role of Toll-like receptor 4 (TLR4)). Therefore, the aims of this project were to develop a more relevant animal model of adolescent alcohol exposure and to characterise its effects on TLR4 signalling and alcohol-related behaviours later life. Balb/c mice received a short (P22-P25), low dose alcohol binge during in early adolescence, and underwent tests to investigate anxiety (elevated plus maze), alcohol seeking (conditioned place preference) and binge drinking behaviour (drinking in the dark) in adulthood. Four doses of alcohol during adolescence increased alcohol-induced conditioned place preference and alcohol intake in adulthood. However, this model did not affect basal elevated plus maze performance. Subsequent analysis of nucleus accumbal mRNA, revealed increased expression of TLR4-related mRNAs in mice who received alcohol during adolescence. To further elucidate the role of TLR4, (+)-Naltrexone, a biased TLR4 antagonist was administered 30 min before or after the adolescent binge paradigm. When tested in adulthood, (+)-Naltrexone treated mice exhibited reduced alcohol intake however, alcohol seeking and anxiety behaviour was unaltered. This study highlights that even a small amount of alcohol, when given during a critical neurodevelopmental period, can potentiate alcohol-related behaviours and TLR4 activation later in life. Interestingly, attenuation of TLR4 before or after adolescent alcohol exposure reduced only binge alcohol intake in adulthood.

Nanoclays are layered aluminosilicate nanostructures. Depending upon the chemical composition and microscopic structure, various nanoclay types have been discovered such as montmorillonite, bentonite, kaolinite, halloysite nanoclay, etc. Nanoclays have been organically modified to develop compatibility with polymers. Polymer/nanoclay nanocomposites have prompted significant breakthroughs in the field of nanocomposite technology. Green nanocomposites form an important class of nanomaterials using naturally derived degradable materials as matrix/nanofiller. This review essentially deliberates the fundamentals and effect of nanoclay reinforcements in the green polymer matrices. Naturally derived polymers such as cellulose, starch, natural rubber, poly(lactic acid), etc. have been employed in these nanocomposites. Green polymer/nanoclay nanocomposites have been fabricated using various feasible fabrication approaches such as the solution route, melt processing, in situ polymerization, and others. The significance of the structure-property relationships in these nanomaterials, essential to attain the desired features, has been presented. Green polymer/nanoclay nanocomposites are light weight, inexpensiveness, ecofriendly, have a low cost, and enhanced indispensable physical properties. Consequently, the green polymer/nanoclay nanocomposites have found applications towards sustainability uses, packaging, membranes, and biomedical (tissue engineering, drug delivery, wound healing) sectors. However, thorough research efforts are desirable to extend the utility of the green polymer/nanoclay nanocomposites in future technological sectors.

In recent years satellite mobile communications systems and market have entered into the era of maturation. Systems like Iridium and Global Star are technically considered as state of the art. This research paper is the result of a feasibility study of utilizing the Low Earth Orbit, Iridium satellite network for the data transfer. The findings of this research, also demonstrate the performance and reliability of the satellite link. A system of data transfer is developed according to a set of specifications, along with the selection of a suitable satellite link. This data collection system is realized in such a way, that there is a software which interfaces the PC of the data transmitting station, with the Iridium satellite constellation; a similar system configuration is present at the data receiving station.

Conventional underwater technologies were not able to provide authentication and proper visualization of unexplored ocean areas to accommodate a wide range of applications. The aforesaid technologies face several challenges including decentralization, beacon node localization (for identification of nodes), authentication of Internet of Underwater Things (IoUTs) objects and unreliable beacon node communication between purpose oriented IoT-enabled networks. Recently, new technologies such as blockchain (BC) and the IoUTs have been used to reduce the issues but there are still some research gaps; for example, unreliable beacon messages for node acquisition have significant impacts on node identification and localization and many constrained node resources, etc. Further, the uncertainty of acoustic communication and the environment itself become problems when designing a trust-based framework for the IoUTs. In this research, a trust-based hybrid BC-enabled beacon node localization (THBNL) framework is proposed to employ a secure strategy for beacon node localization (BNL) to mine the underwater localized nodes via the hybrid blockchain enabled beacon node localization (HB2NL) algorithm. This framework helps to merge two disciplines; it is hybrid because it follows the nature and bio inspired meta heuristics algorithms for scheduling the beacon nodes. The performance of the proposed approach is also evaluated for different factors such as node losses, packet delivery ratios, residual and energy consumption and waiting time analysis, etc. These findings show that the work done so far has been successful in achieving the required goals while remaining within the system parameters.

Abstract In designing a parallel resonant induction heating system, selecting a suitable capacitor for its parallel circuit is very important. To properly select this capacitor, several solutions have been proposed such as using Lagrange method, standard bacterial foraging and genetic algorithms. Although some of these methods have been performed well, they have not considered either some restrictions or a multi-objective function in their design. To obtain an optimal value for the capacitor, this paper utilizes a bio-inspired optimization method called smart bacterial foraging algorithm (SBFA). SBFA is modeled based upon the foraging behavior of bacteria including the individual and social intelligences. SBFA uses a multi-objective optimization function including efficiency, power output and difference between power loss and output by taking the voltage and resonant frequency limitations into consideration. In order to demonstrate the efficiency and performance of the proposed approach, this paper simulates it using MATLAB. Then, the simulation results are compared with two existing algorithms: standard bacterial foraging and genetic algorithms. Based upon the results, SBFA is outperformed in comparison with the aforementioned algorithms in selecting the optimum capacitance. Results point to the fact that there can be different resonant frequencies with respect to the different capacitances of the heater as well as that for one of these frequencies the objective function has a minimum value. In addition, findings show a Pareto-Efficient situation for efficiency and power output value in an induction heating system.

Sometimes, an increased reaction is caused by an immune system of the body to a non-toxic agent (e. g. eggs, dust, pollens or some drugs). This is called allergy or hypersensitivity. The regulatory T cells decrease these allergic reactions. Nowadays, it is noticed that immune system has a deep relationship with micro-organism present in the intestine, that can be explained by the example, that some bacteria of intestine increase production of Treg cells by producing butyric acid like fatty acids. This can also understand that sufficiently different types of T cell receptors of Treg cells are needed to stop the inflammatory response produced by intestinal bacteria. In this study, the dynamic relation of T helper cells, intestinal bacteria and Treg cells are illustrated by a conformable mathematical model. Memory effects are figured out and displayed through graphs. Different plots also show the effects of increasing/decreasing amount of Treg induction efficiency on the whole system.

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Adaptive transparent system (ATS) is an aspiring and effective building system that can adapt itself through environmental changes in spontaneous and reversible ways. It proposes an automatic and real-time response to indoor and outdoor conditions by increasing building energy efficiency and user comfort. This research presents a critical analysis to provide a preference order of the smart materials being used in the adaptive transparent systems. The approach of using smart material technologies in the building façades is discussed as the promising research direction for the future. A comprehensive literature review is conducted to identify the smart materials used in adaptive transparent systems along with their properties. Seven types of smart materials that are aerogel (AG), phase change material (PCM), photovoltaic (PV), electrochromic (EC), thermo-chromic (TC), thermo-tropic (TT), and liquid crystal polymers (LCP) are selected based on evaluation criteria determined by the literature. The identified criteria are bulk density (BD), thermal conductivity (TCd), sound insolation (SI), fire retardation (FR), heat transfer coefficient (HTC), solar transmittance (ST), air purification (AP), annual energy saving (AES), cost saving (CS), ultraviolet (UV)/near infrared (NIR) control (UNC), and embodied carbon (EC). The identified seven smart materials are investigated with the help of two multi-criteria decision-making (MCDM) techniques named analytical hierarchical process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS) for analysis and ranking of materials. Results of the analysis demonstrate that PV is the most optimum material for adaptive transparent systems while others are ranked according to their performance.