The objective of this research was to evaluate the effects of public debt sustainability on economic growth in the period 2000-2021 and establish a new optimal debt level that does not affect Peru's economic growth. The general method used to determine this effect was the hypothetical deductive method with a non-experimental and longitudinal trend design, because the data to be analyzed are variations that have occurred over time; the VAR (vector autoregressive) model was used as a specific method, because the evidence was insufficient to consider the simultaneity between the reactions of the variables to propose an SVAR model. Data were collected from economic portals such as the Ministry of Economy and Finance (MEF), as well as the Central Reserve Bank of Peru (BCRP). The estimated sample size was 88 observations representing all quarters from 2000 to 2021. As a result of the econometric regression, the impact of the level of public debt on economic growth is positive, since a one-unit increase in the percentage of public debt will increase the variation of GDP by almost 1.1%. Regarding the debt level forecast and according to the projection made, it was determined that the new debt level that does not affect the sustainability of public finances or the long-term economic growth of the Peruvian economy should be 38% of GDP.

The food industry consumes large amounts of water although there is an increasing demand for water and a rapid decrease in the level of natural water resources. Wastewater resulting from food industries needs to be assessed for their compliance to standards. In this study, wastewater treatment steps from the food industry were investigated for accurate assessment of wastewater loading by analyzing parameters of the concentration of compounds present in the effluents. The results revealed that the parameters of treated wastewater were as follow, electrical conductivity 2931 μs/cm, total suspended solids 100 mg/L, biochemical oxygen demand 90 mg/L, chemical oxygen demand 250 mg/L, total phosphorus 7.9 mg/L, and total nitrogen 70 mg/L. This exerts a huge load on the biological treatment unit. Thus, this study offers an understanding and support in selecting appropriate treatment for industrial wastewater to obtain an effluent suitable in compliance with standards of the environmental quality.

Pulvinaria tenuivalvata (Newstead) (Hemiptera: Coccidae) red soft scale insect is one of the most prevalent insect pests that attacks sugarcane plants. Insecticidal efficiency of six selected insecticides (Malatox, Sulfar, Admiral, Nomolt, Tafaban and Biover) was evaluated for their impact against nymphs and adult females of P. tenuivalvata on sugarcane leaves using leave dipping methods. This investigation was carried out for two successive seasons (July 2021-2022) at the laboratory of the Plant Protection Research Department at the El-Mattana Agricultural Research Station, Luxor Governorate, Egypt. Obtained results showed that the tested insecticides varied in efficacy on the different stages of pest (nymphs and adult females). Moreover, the nymphal stage of P.tenuivalvata was more susceptible to the tested pesticides compared to the adult stage. Admiral and nomolt were the most toxic against the nymphal and adult female stages of P. tenuivalvata on sugarcane leaves, sulfar, however, was the least successful in controlling this pest.

Vehicle routing problem (VRP) is a classic problem studied in logistic. One of the most important variations within this problem is called Green Vehicle Routing Problem (GVRP), in which environmental aspects are considered when designing product delivery routes. This variant arises due to the high levels of pollution produced by transport vehicles, so it is a variation whose study represents a vital impact nowadays. This project will consider a GVRP and will be developed considering the characteristics of multi-depot (MDVRP) and multi-product (MPVRP) to minimize the costs of assignation of vehicles and CO2 emissions. To solve the problem, this project proposes a hybridization between the classic tabu search (TS) metaheuristic and the PAES algorithm (TS+PAES) to generate the Pareto frontier of both objectives. An integer mixed linear programming model is formulated and developed for each objective function separately to have an optimal point of comparison for the efficiency of the proposed algorithm. Also, the TS+PAES algorithm is compared to the nearest neighbor algorithm for large instances. Two computational experiments were carried out, one for small and the other one for large instances. The experiment for small instances showed that the GAP of each extreme of the frontier compared to the MILP model is on average 0.73%. For large instances, the metaheuristic improves in 0.1% the results presented by the MILP model showing that the metaheuristic provides closer near-optimal solutions in less computational time. Besides, the metaheuristic, in comparison with the nearest neighborhood heuristic, improves in 44.21% the results of emissions and in 3.88% the costs. All these results demonstrate the effectiveness of the metaheuristic.

The non-stoichiometric, calcium-deficient hydroxyapatite was prepared through a low-temperature from aqueous solutions method and characterized using Physico-chemical methods. The potential of this hydroxyapatite to adsorb and release insulin from aqueous solutions was evaluated under physiological conditions. The effect of contact time and initial concentration were studied in batch experiments. The adsorption rate reached up to 81±5% in the first half-hour of contact, while the release rate of insulin incubation was about 41 ± 5% after 1 hour. The pseudo-first-order, pseudo-second-order, Elovich equation, Weber and Morris intraparticle diffusion model and Bangham’s pore diffusion model were applied to study the kinetics of the adsorption process. The pseudo-second-order kinetic model provided the best correlation R²(0.998) of the used experimental data compared to the other models. The adsorption of insulin onto hydroxyapatite was correlated well R²(0.998) with the Langmuir model as compared to Freundlich, Temkin and Dubinin–Kaganer–Radushkevich (D-K-R) models, with a maximum adsorption capacity of 24.46 mg/g. The isotherms parameters values of ΔG⁰, b_t and E show that the adsorption process is favorable, spontaneous, exothermic, and controlled by physisorption. The point of zero charge (pHZPC) of hydroxyapatite and the isoelectric point (pI) of insulin indicate that the interaction of insulin molecules with prepared apatite can be well described as an ions exchange reaction.

E-commerce is one of the industries most affected by big data, from collection to analytics in the highly competitive market. Previous research on big data analytics in E-commerce focused only on particular applications, and there is still a gap in presenting a framework to evaluate big data applications from a challenges-values point of view. This study employs a three-phase methodology to evaluate big data applications in E-commerce with respect to big data challenges and values using a hybrid multi-criteria decision-making technique that combines BWM and fuzzy TOPSIS. The results showed process challenge and the strategic value obtained the highest weight for challenges and values criteria. Financial fraud detection is relatively the most challenging, and online review analytics is the most valuable application of big data in E-commerce among identified applications. Evaluating big data applications based on cost and benefit criteria is practical for E-commerce managers and experts to make decisions on implementation priorities to overcome the challenges and make the most of values. Moreover, the proposed approach is not only limited to big data analytics in E-commerce and can also be applied in other industries to evaluate emerging technology applications.

An experimental investigation was undertaken to study the Cobalt-based Stellite 6, powder deposited on SS 304 stainless steel substrate without any intermittent layer using an atmospheric plasma spray deposition process by varying the thickness of coating in the range of 74 µm, 128 µm, and 215 µm. The effect of coating thickness on metallurgical properties and corrosion resistance behavior was investigated. Optical microscopy, Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDS) were employed to study the morphology of Stellite 6 coating. X-Ray Diffraction was used for structural analysis and to identify the phase formation. It was observed that the sample with 128 µm coating thickness provides the best result concerning microhardness and microstructure characteristics whereas the sample with 215 µm coating thickness provides the best corrosion resistance property. The reasons for the deviation were investigated and the factors responsible for the deviation were assigned in this investigation.

This study was conducted to consider the relationship between the transportation export value (TR) and energy consumption of Thailand (EN) in the long run by a comparative analysis that relied on testing by the ARDL and NARDL models. The Granger causality of each item was also tested by quarterly time series data from Quarter 1 of 2011-Quarter 4 of 2021. The results revealed a long relationship from the EN to TR. However, only the reduction of the TR affected the EN. According to the results, the energy agencies of Thailand should maintain the balance of EN and sufficient energy imports to drive the TR for its stability.

In a bid to discovering novel antibiotics to combat growing trend of multi-drug resistance strains of Salmonella typhi, 48 new pyridine derivatives with significant inhibitory activities against the aforementioned bacterium were subjected to molecular docking against DNA gyrase protease of the bacterium, drug likeness evaluation and pharmacokinetics profiling. All the 48 leads displayed better binding affinity values when compared with Amoxicillin, Ciprofloxacin, Ceftriaxone, Ampicillin, and chloramphenicol, the standard antibiotics used herein for quality assurance. Furthermore, the majority of the compounds were, however, screened out due to their poor pharmacokinetics profiles and drug-likeness. Only five compounds emerged as the most promising leads and they include C4 with binding affinity of -8.0 kcal/mol, C8 (-8.6 kcal/mol), C9 (-8.1 kcal/mol), C26 (-8.3 kcal/mol), and C27 (-8.0 kcal/mol). These compounds not only displayed better binding affinity when compared with the reference antibiotics but also exhibit different modes of interactions with the target protease of the bacterium making them more potent and drug like. Toxicity evaluation of the leads also revealed that the compounds are neither tumorigenic nor mutagenic. In view of the excellent binding affinity, high pharmacokinetics profile and positive drug-likeness of the novel ligands, we recommend these promising compounds for in vitro and in vivo studies in order to discover novel antibiotics that could curb the dangerous trend of multiple drug resistance by Salmonella typhi.

With Newsvendor Problem (NvP) we refer to a specific class of inventory management problems, valid for a single item with stochastic demand over a single period. In the standard version, the newsvendor is allowed to issue a single order, before he or she can observe the actual demand. Since the newsvendor can face both overage and underage costs, due to lost sales or residual stock, the objective is to define the optimal order size that maximizes the expected profit. In this paper, we consider a specific version of the NvP, in which the buyer has the opportunity to make a last and single order for opportunistic reasons. Specifically, we consider discontinued, collectible items, for which demand will not vanish and whose value might appreciate. Hence, the objective is to define the optimal quantity that should be purchased, just before the item is retired from the market or sold-out, and that should be sold as soon as the price rises over a predefined target level. An optimal solution, maximizing the expected profit, is obtained both in case of negligible and non-negligible stockholding costs. In the latter case, to obtain the optimal solution in implicit form, some simplifying assumptions are needed. Hence, a thorough numerical analysis is finally performed, as a way to empirically demonstrate both the robustness and the accuracy of the model, in several scenarios differentiated in terms of costs and customers’ demand.