Finite rotations in dynamics of beams and implicit time-stepping schemes

We examine theoretical and computational aspects of three-dimensional finite rotations pertinent to the dynamics of beams. The model problem chosen for consideration is the Reissner beam theory capable of modelling finite strains and finite rotations in geometrically exact manner. Special emphasis is placed on clarifying the geometry aspects, finite rotation updates and the associated linearization procedure pertaining to different choices of rotation parameters. The latter is shown to play an important role in constructing the optimal implementation of a time-stepping scheme. © 1998 John Wiley & Sons, Ltd.     

Investigation of Metabolome Underlying the Biological Mechanisms of Acute Heat Stressed Granulosa Cells

Heat stress affects granulosa cells and the ovarian follicular microenvironment, ultimately resulting in poor oocyte developmental competence. This study aims to investigate the metabo-lomics response of bovine granulosa cells (bGCs) to in vitro acute heat stress of 43 °C. Heat stress triggers oxidative stress-mediated apoptosis in cultured bGCs. Heat-stressed bGCs exhibited a time-dependent recovery of proliferation potential by 48 h. A total of 119 metabolites were identified through LC–MS/MS-based metabolomics of the spent culture media, out of which, 37 metabolites were determined as differentially involved in metabolic pathways related to bioenergetics support mechanisms and the physical adaptations of bGCs. Multiple analyses of metabolome data identified choline, citric acid, 3-hydroxy-3-methylglutaric acid, glutamine, and glycocyamine as being upregulated, while galactosamine, AICAR, ciliatine, 16-hydroxyhexadecanoic acid, lysine, succinic acid, uridine, xanthine, and uraconic acid were the important downregulated metabolites in acute heat stress. These differential metabolites were implicated in various important metabolic pathways directed towards bioenergetics support mechanisms including glycerophospholipid metabolism, the citrate cycle (TCA cycle), glyoxylate and dicarboxylate metabolism, and serine, threonine, and tyrosine metabolism. Our study presents important metabolites and metabolic pathways involved in the adaptation of bGCs to acute heat stress in vitro.     

Metabolic fingerprint of patients showing responsiveness to treatment of septic shock in intensive care unit

Magnetic Resonance Materials in Physics, Biology and Medicine - An early metabolic signature associated with the responsiveness to treatment can be useful in the better management of septic shock...     

Selection of Wind Turbine Systems for the Sultanate of Oman

The Sultanate of Oman has been dealing with a severe renewable energy issue for the past few decades, and the government has struggled to find a solution. In addition, Oman’s strategy for converting power generation to sources of renewable energy includes a goal of 60 percent of national energy demands being met by renewables by 2040, including solar and wind turbines. Furthermore, the use of small-scale energy from wind devices has been on the rise in recent years. This upward trend is attributed to advancements in wind turbine technology, which have lowered the cost of energy from wind. To calculate the internal and external factors that affect the small-scale energy of wind technologies, the study used a fuzzy analytical hierarchy process technique for order of preference by similarity to an ideal solution. As a result, in the decision model, four criteria, seventeen sub-criteria, and three resources of renewable energy were calculated as options from the viewpoint of the Sultanate of Oman. This research is based on an examination of statistics on energy produced by wind turbines at various locations in the Sultanate of Oman. Further, six distinct miniature wind turbines were investigated for four different locations. The outcomes of this study indicate that the tiny wind turbine has a lot of potential in the Sultanate of Oman for applications such as homes, schools, college campuses, irrigation, greenhouses, communities, and small businesses. The government should also use renewable energy resources to help with the renewable energy issue and make sure that the country has enough renewable energy for its long-term growth.     

Effects of repeated frying on physicochemical characteristics,oxidative stress,and free radical scavenging potential of canola oil and ghee

The repeated use of cooking oils and ghee for the deep frying of food materials may affect their nutritional quality. The present study evaluated the effect of repeated frying on the physicochemical characteristics and antiradical potential of canola oil and ghee. The oil and ghee were used for frying of fish and chicken for 2, 4, 6, 8, and 10 frying cycles followed by the analysis of physicochemical, oxidative stress, and antiradical parameters. Regression analysis of the data showed a frying cycle-dependent significant linear increase in saponification (R² = 0.9507–0.9748), peroxide and acid values (R² = 0.956–0.9915), and malondialdehyde (MDA) production (R² = 0.9058–0.9557) of canola oil and ghee subjected to fish and chicken frying but exponential increase in saponification value (R² = 0.9778) and MDA production (R² = 0.7407) of canola oil and ghee used for fish frying. The increase in the number of frying cycles linearly decreased the iodine value (R² = 0.9781–0.9924), and 1, 1-diphenyl-2-picrylhydrazyl, hydroxyl, and 2, 2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) radical scavenging potential (R² = 0.9089–0.9979) of canola oil and ghee. Repeated frying in cooking oil and ghee increases oxidative stress and decreases their physicochemical and antioxidant qualities. Canola oil was comparatively more oxidative resistant than canola ghee. The regression equations derived from regression analysis will guide researchers to conduct similar types of univariate studies.     

Nanoarchitectonics: Porous Hydrogel as Bio-sorbent for Effective Remediation of Hazardous Contaminants

The increasing use of heavy metals, dyes, and other metallic or chemical elements causes crucial environmental pollution. Sewage that contains these heavy metals and dyes is discharged into the atmosphere and goes directly into the food cycle, causing cancerous diseases and health deterioration in living organisms. The supreme concern of today’s research is to treat wastewater and effectively remove the hazardous dye molecules from aqueous media and other environmental matrices. Nowadays, technologies are applied to rectify organic and inorganic pollutants from sewage. Among them, adsorption is a fascinating way because it is environmentally friendly, feasible, and economical biomaterials. Chitosan (CS) as bio-sorbent is endowed with valuable characteristics, such as biodegradability, biocompatibility, high reactivity, low-cost, and functional groups (–OH and NH₂) on its surface. CS is used for many applications, either as a single component or composite form. The use of CS as bio-adsorbents is beneficial over regular adsorbents. Chitosan-based hydrogel is one of the very important bio-adsorbents. All these bio-adsorbents are highly used to eradicate toxic dyes, digest harmful industrial sewage, and eliminate pesticides, climatic hazardous waste, and contaminated materials from the environment.

     

Synthesis and Characterization of Some Complexes Derived from Isatin Dye Ligand and Study of their Biological Potency and Anticorrosive Behavior on Aluminum Metal in Acidic Medium

Divalent Mn, Ni, Zn, and trivalent La complexes of H₃L ligand [N’,2-bis((Z)-2-oxoindolin-3-ylidene)hydrazine-1 carbohydrazide] were synthesized and characterized via diverse spectroscopic methods (FT-IR, NMR, electronic, PXRD, and GC-MS), molar conductance and magnetic susceptibility measurements. The different ways of binding for the H₃L ligand with metal ions were inferred, as the H₃L ligand acted in mono-negative N²O tridentate, mono-negative N²O³ pentadentate, bi-negative N²O³ pentadentate, and tri-negative N²O³ pentadentate manners in coordination to Mn²⁺, Zn²⁺, La³⁺, and Ni²⁺ metal ions, respectively. DFT modeling was performed using the DMOL³/material studio software, and some of the experimental outcomes were interpreted and authenticated. Electrochemical performance of Mn²⁺ ions in the existence and absence of H₃L ligand was considered via cyclic voltammetry. The corrosion effectiveness of the H₃L ligand (inhibitor) to aluminum metal was evaluated, and the molecular dynamic (MD) simulations for adsorption of the H₃L inhibitor on Al surface were performed via FORCITE quench code. The isolated compounds were inspected for their antimicrobial (against C. albicans fungi, G⁺ bacteria S. aureus and B. subtilis, and G^? bacteria P. aeruginosa and E. coli), cytotoxic, and antioxidant (ABTS, and SOD) activities. A molecular docking study was performed to give the favorable binding sites for the ligand to E. coli, and S. aureus proteins.

     

Process improvement and efficiency analysis using the Single-Minute Exchange of Dies method applied to the set-up and operation of screen-printing machines

Lean manufacturing methods are concerned with simplifying the production process and thus maximising efficiency and minimising wastage. All production processes contain several steps, which include sub-steps such as cleaning and changing devices and preparing the production areas for later steps. Most of these sub-steps require that machines are stopped and therefore they must be performed as quickly as possible. This downtime causes a decrease in efficiency, while increasing the costs and production time. Single-Minute Exchange of Dies (SMED) is a lean manufacturing strategy that has been applied successfully in many sectors to minimise excessive downtime. In this study, the SMED technique is applied in a textile screen-printing company for the case of changing the screens between each design. The steps are evaluated and designated as either external steps, which are performed without downtime, or internal steps, which take place during downtime. The number of external steps is increased while being decreased for internal steps. Also, the production time decreased by 54% and a 32% increase in efficiency was achieved during the screen-printing production of a sample t-shirt.