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This study aims to identify the optimal parameters for regulated metal deposition (RMD) and flux-cored arc welding (FCAW) processes when joining 316LN stainless steel. The objective was to determine the optimal settings for current (A), voltage (V), and gas flow rate (GFR, L/min) to achieve the desired weld bead characteristics, including bead width (BW), bead height (BH), depth of penetration (DOP), and heat-affected zone (HAZ). A Box–Behnken design based on response surface methodology was employed for the bead-on-plate trials. Mathematical models were developed from the experimental data and validated through analysis of variance and residual analysis, with R-squared values confirming model accuracy. The heat transfer search (HTS) algorithm was used for both single objective and multiobjective optimization. For RMD, optimal results were achieved with a BW of 9.95 mm, BH of 4.39 mm, DOP of 2.26 mm, and HAZ of 0.29 mm, at 130 A, 18 V, and 20 L/min GFR. For FCAW, optimal values were a BW of 11.45 mm, BH of 3.59 mm, DOP of 2.15 mm, and HAZ of 0.40 mm, at 210 A, 24 V, and 10 L/min GFR. The Pareto solutions offered a most suitable choice of the optimal configuration, balancing the desired BW, BH, DOP, and HAZ values. The effectiveness of the HTS algorithm is demonstrated by the minimal differences between predicted and measured values, highlighting its high accuracy in optimizing 316LN stainless steel welding parameters.Article highlights: Adjusted welding settings for current, voltage, and gas flow to get the best weld quality. Tested different settings and created accurate models to predict welding results. Used a smart method to find the best welding options and balance quality. [ABSTRACT FROM AUTHOR]

It is commonly known that a number of variables, including price, supply levels, time, and green level, affect how quickly certain things are in demand. Furthermore, the inventory carrying cost is considered to be a nonlinear representation of time and is subject to variation throughout time. More precisely, it rises with time since longer storage times necessitate more costly warehouse space. This study presents a fully backlogged situation inventory system for a single commodity where the product's selling price, green level, and time are used to simultaneously compute the demand rate in accordance with a power pattern. Purchase price is determined by the product's nonlinear green level. Complete backorders are available for shortages. The impact of the product's selling price, green level and time power function are combined to determine the product's demand. Moreover, the holding cost also rises as the product is stored for a longer period of time. The primary goal is to determine the best inventory policy to maximise total profit per unit of time. Though the problem is highly nonlinear in nature. Hence, we cannot solve it analytically. To overcome these difficulties, we have applied several well-known popular metaheuristic algorithms (Water Cycle Algorithm (WCA), Artificial Electric Field Algorithm (AEFA), Teaching Learning Based Optimization Algorithm (TLBOA), Grey Wolf Optimizer Algorithm (GWOA), Sparrow Search Algorithm (SSA), Whale Optimizer Algorithm (WOA), Prairie Dog Optimization Algorithm (PDOA), Gazelle Optimization Algorithm (GOA), A Sinh Cosh Optimizer Algorithm (SCHOA) and White Sherk Optimizer Algorithm (WSOA), Archimedes Optimization Paradigm Algorithm (AOPA), Marine Predator Optimization Algorithm (MPOA), Geyser Inspired Algorithm (GIA), Runge Kutta Optimization Algorithm (RKOA), Lungs Performance-based Optimization Algorithm (LPOA) and Dwarf Mongoose Optimization Algorithm (DMOA)). It is observed that WCA perform better than other algorithms with respect to the convergence rate. A numerical example is taken in order to validate the proposed model. Finally, a post optimality analysis is performed in order to make a fruitful conclusion. [ABSTRACT FROM AUTHOR]

In this work, 6-mm-thick ASTM A387-11–2 steel plates have been butt welded at optimized parametric settings of current (A) = 100 A, voltage (V) = 13 V, and gas flow rate (GFR) = 21 L/min. The as-welded plates have been visually inspected for any surface defects and were found to be defect-free. Further, the weldments were subjected to macroscopic metallography to explore the weld bead geometry. Macroscopic results reveal that the RMD process produces a higher depth of penetration (DOP) and lower heat-affected zone (HAZ) as compared to the GMAW process. Optical and scanning electron microscopy have also been done to examine the internal microstructure in the weldments. The result of microscopic analysis reveals the presence of pearlite and ferrite in the base metal. The process of grain refinement in the heat-affected zone and weld zone was also observed in the form of fine-grain particles which confirms the presence of martensite in the weld zone. In addition to this, the microhardness values for both weldments were measured and compared. The microhardness of GMA weldments was found to be too high in all the zones as compared to that of RMD weldments and hence gives the affirmation with the obtained microstructures in the welded samples. [ABSTRACT FROM AUTHOR]

The trade credit policy plays a significant role to minimize the risk or maximize the revenue from a business. Thus, the consideration of trade credit policy with single or multiple credit period(s) makes an inventory model more realistic. This work aims to establish a preservation technology-based non-instantaneous deteriorated inventory model considering multi-period-based trade credit policy and variable demand dependent on selling price of the item and displayed inventory level. For different credit periods, different rates of interest are charged. Also, different cases are investigated in formulating the mathematical model. Then to maximize the average profits in all these cases, different advanced variants of quantum-behaved particle swarm optimization techniques are applied. Thereafter all the cases of the proposed model are justified with the help of five numerical examples. Finally, in order to study the effect of the changes of different system parameters on the optimal policy, the sensitivity analyses are performed, and the work is concluded with some real-life implications and future research plans. [ABSTRACT FROM AUTHOR]

Generally, most of the inventory costs are not always fixed due to uncertainty of competitive market. In the existing literature, it is found that several researchers have worked on uncertainty considering inventory parameters as fuzzy valued. In this work, we have represented the inventory parameters as interval. Using this concept, we have developed a two-warehouse inventory model with advanced payment, partial backlogged shortages. Due to uncertainty, this problem cannot be solved by existing direct/indirect optimization technique. For this purpose, different variants of particle swarm optimization techniques (viz. PSO-CO, WQPSO and GQPSO) have been developed to solve the problem of the proposed inventory model by using interval arithmetic and interval order relations. Finally, to illustrate and also to validate the proposed model, a numerical example has been solved and the best found solutions (which is either optimal solution or near optimal solution) obtained from different variants of PSO have been compared. Then, a sensitivity analysis has been performed to study the effect of changes of different parameters of the model on the optimal policy. [ABSTRACT FROM AUTHOR]

Activation of the angiotensin 1-7/Mas receptor (MasR) axis counteracts angiotensin II (Ang II)-mediated cardiovascular disease. Recombinant human angiotensin-converting enzyme 2 (rhACE2) generates Ang 1-7 from Ang II. We hypothesized that the therapeutic effects of rhACE2 are dependent on Ang 1-7 action. Wild type male C57BL/6 mice (10-12 weeks old) were infused with Ang II (1.5 mg/kg/d) and treated with rhACE2 (2 mg/kg/d). The Ang 1-7 antagonist, A779 (200 ng/kg/min), was administered to a parallel group of mice. rhACE2 prevented Ang II-induced hypertrophy and diastolic dysfunction while A779 prevented these beneficial effects and precipitated systolic dysfunction. rhACE2 effectively antagonized Ang II-mediated myocardial fibrosis which was dependent on the action of Ang 1-7. Myocardial oxidative stress and matrix metalloproteinase 2 activity was further increased by Ang 1-7 inhibition even in the presence of rhACE2. Activation of Akt and endothelial nitric oxide synthase (eNOS) by rhACE2 were suppressed by the antagonism of Ang 1-7 while the activation of pathological signaling pathways was maintained. Blocking Ang 1-7 action prevents the therapeutic effects of rhACE2 in the setting of elevated Ang II culminating in systolic dysfunction. These results highlight a key cardioprotective role of Ang 1-7, and increased Ang 1-7 action represents a potential therapeutic strategy for cardiovascular diseases. Key messages: [ABSTRACT FROM AUTHOR]

An introduction to articles published within the issue is presented, including the pleotropic effects of 1 year dietary intervention with resveratrol containing grape extract on inflammatory as well as fibrinolytic status in patients with stable coronary artery disease (CAD) and another on the use of resveratrol rich grape extract in dietary intervention of CAD patients.

A novel angiotensin-converting enzyme (ACE) homolog, named ACE2, is a monocarboxypeptidase which metabolizes several peptides. ACE2 degrades Angiotensin (Ang) II, a peptide with vasoconstrictive/proliferative effects, to generate Ang-(1-7), which acting through its receptor Mas exerts vasodilatory/anti-proliferative actions. In addition, as ACE2 is a multifunctional enzyme and its actions on other vasoactive peptides can also contribute to its vasoactive effects including the apelin-13 and apelin-17 peptides. The discovery of ACE2 corroborates the establishment of two counter-regulatory arms within the renin-angiotensin system. The first one is formed by the classical pathway involving the ACE-Ang II-AT receptor axis and the second arm is constituted by the ACE2-Ang 1-7/Mas receptor axis. Loss of ACE2 enhances the adverse pathological remodeling susceptibility to pressure-overload and myocardial infarction. ACE2 is also a negative regulator of Ang II-induced myocardial hypertrophy, fibrosis, and diastolic dysfunction. The ACE2-Ang 1-7/Mas axis may represent new possibilities for developing novel therapeutic strategies for the treatment of hypertension and cardiovascular diseases. In this review, we will summarize the biochemical and pathophysiological aspects of ACE2 with a focus on its role in diastolic and systolic heart failure. [ABSTRACT FROM AUTHOR]