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Expansive soils are problematic for direct engineering applications in their natural state because of the shrink-swell phenomenon. Numerous stabilizers and methods have been used to stabilize expansive soils as an effort to make them more practical for construction purposes. Searching for suitable soil stabilizers to overcome difficulties caused by the expansive soils is the key issue, not only in terms of achieving the required soil geotechnical characteristics but also in terms of environmental and economic concerns. The purpose of this article was to assess the current trends, challenges, and opportunities of various admixtures utilized for expansive soil improvement, as well as their economic and environmental consequences. A critical review of various admixtures commonly used as soil stabilizers, including marble waste powder, fly ash, eggshell powders, stone waste, and lime powder is conducted. Furthermore, a the review was also focused to analyze the offered stabilizers in terms of soil geotechnical properties and sustainability in the field application.

Genus Pinus is a widely dispersed genus of conifer plants in the Northern Hemisphere. However, the inadequate accessibility of genomic knowledge limits our understanding of molecular phylogeny and evolution of Pinus species. In this study, the evolutionary features of complete plastid genome and the phylogeny of the Pinus genus were studied. A total of thirteen divergent hotspot regions (trnk-UUU, matK, trnQ-UUG, atpF, atpH, rpoC1, rpoC2, rpoB, ycf2, ycf1, trnD-GUC, trnY-GUA, and trnH-GUG) were identified that would be utilized as possible genetic markers for determination of phylogeny and population genetics analysis of Pinus species. Furthermore, seven genes (petD, psaI, psaM, matK, rps18, ycf1, and ycf2) with positive selection site in Pinus species were identified. Based on the whole genome this phylogenetic study showed that twenty-four Pinus species form a significant genealogical clade. Divergence time showed that the Pinus species originated about 100 million years ago (MYA) (95% HPD, 101.76.35–109.79 MYA), in lateral stages of Cretaceous. Moreover, two of the subgenera are consequently originated in 85.05 MYA (95% HPD, 81.04–88.02 MYA). This study provides a phylogenetic relationship and a chronological framework for the future study of the molecular evolution of the Pinus species.

Influence of co-dopings of divalent ions such as Mg2+, Zn2+, Cd2+ and Sr2+ ions in Mn4+-doped CaAl12O19 red phosphor on its photoluminescence characteristics has been investigated. Samples of Mn4+-doped CaAl12O19 and co-doped with Mg2+, Zn2+, Cd2+ and Sr2+ ions were synthesized by a solid-state reaction method. Significant enhancement of photoluminescence intensity was observed, when Mg2+ and Zn2+ were co-doped in Mn4+-doped CaAl12O19, while only slight enhancement was seen with Cd2+ and Sr2+ co-dopings. To investigate these differences in photoluminescence enhancement, change in local environment of Mn4+ ions due to co-dopings of divalent ions was examined by electron spin resonance (ESR) measurements and first principles calculations within a density functional theory. From these experimental and theoretical analysis, it has been confirmed that the local environment of Mn4+ changes significantly with Mg2+ and Zn2+ co-dopings, while Cd2+ and Sr2+ alter minimally the local environment of Mn4+ due to different substitution site.

The use of robotics in executing agricultural tasks has significantly improved productivity over the years as a result of automation in performing such activities as spray, harvesting, planting etc. In order to optimize both crop yield and quality while minimizing costs, there will be need for the application of navigation strategies. These will provide optimal as well as autonomous navigation capability which is built entirely upon field coverage plan thereby making robot navigation approach a paramount scheme. In this paper, the autonomy of an agricultural mobile robot is enhanced in a structured environment (greenhouse farm) to locate an optimum route such that the robot performs a selective and variable spray of pesticides to the plants. To realize this, a robust vehicle routing problem (VRP) scheme is designed to navigate the robot autonomously while making intelligent decisions to fulfil the pesticide demands at each node (infected plants). The improved non-dominated sorting genetic algorithm (INSGA-III) is adopted to solve this fully integer problem based on three (3) test cases carried out with 8, 32 and 56 infected plants respectively for validation. The results obtained show a trade-off solution as the Optimal INSGA-III is significantly lower than NSGA-III in terms of solution quality. On the other hand, a significant reduction in run times of between 66% and 76% and 76–93% was obtained for all test case scenarios for population sizes of 100 and 1500 respectively.

Printed flexible electronics have been extensively studied for their potential use in various applications. In this paper, a simple, low-cost, high-conductivity (0.2Ω/sq) flexible electronic circuit fabrication method is demonstrated. The commercial PET film is used as a flexible substrate, and then nanoparticle silver ink was inkjet printed on its surface, and then the flexible Ag circuit was obtained after sintering with 150 °C hot air. Although the conductance is somewhat reduced, the electronic circuits made in this way remain functional even under different folding angles or after repeated folding. The proposed development technique allows cheap, efficient, and large-scale production of flexible electronic circuits with excellent mechanical and electrical properties.

TENG (triboelectric nanogenerator) has shown unique application prospect as a powerful way of harvesting renewable energy in micro-scale self-powered systems. The contact-separation (CS) arched TENG is so convenient that made a great progress in the past years. Laser ablated micro-nano structure on the surface of TENG triboelectric layers possesses a critical impact on its performance. However, arbitrary laser parameters do not provide a direct enhancement of the TENG output, but rather a different degree of degradation. The UV-nanosecond laser (Ultraviolet nanosecond laser) engraving parameters were optimised during the enhancement of the arched TENG using UV-nanosecond laser etching. Evaluation and analysis of the engraved friction layer coupling, electrode substrate arrangement and optimization curves was carried out, which provides an important reference for UV nanosecond laser etching TENG contribute to large-scale application of renewable energy.

The shortage of conventional feedstuff is one of the rising issues faced by the developing countries of the world. To bridge the gap between supply and demand of the major feedstuff it is desirable to practice the use of non-conventional feed resources. Duckweeds are the aquatic macrophytes growing in stagnant water bodies that offer a choice to be used as an alternate feed. Before the use of any alternate feed, it is vital to know the nutritional composition of the feed under diverse environmental conditions. The objective of this study was to investigate the influence of salinity, abiotic stress, on the proximate composition of duckweed (Lemna minor L.). The experiment was laid out in Completely Randomized Design (CRD) with 3 repeats. Data was collected on protein, lipid, carbohydrate, and mineral contents. In the laboratory trial plants were grown under the saline condition of different concentrations ranging from 2 g NaCl L−1 to 12 g NaCl L−1 for a growing period of 20 days. The biomasses obtained were tested for proximate composition. ANOVA of the result exhibited a significant effect of salinity on the proximate composition of the plant. Protein residues of the plant started declining above the concentration of 4 g NaCl L−1 until the lowest value was obtained at 12 g NaCl L−1. Lipid composition showed more sensitivity to the stress with a sharp decline above 2 g NaCl L−1 having a minimum value at 12 g NaCl L−1. Carbohydrate contents increased with increasing salinity up to 6 g NaCl L−1 above which a decrease was observed. The highest accumulation of the macronutrients i.e., Ca, Mg, took place in the lower range of concentration of the salt. The percentage compositions of micronutrients such as Fe, Mn, and Zn percentage were reduced at a higher range of salinity while the optimum level was recorded in plants treated with 2 g NaCl L−1, followed by control. The total accumulation of both macro and micronutrients was higher in the plant material treated with a lower level of salt concentration, concluding a significant effect of salinity on proximate composition. As for the Indus water salinity level, the plant has the capacity of tolerance and can be grown without affecting its proximate composition.

Oxidative stress, chronic inflammation and apoptosis are associated with obesity. Herein, we investigated the potential protective effect of bee bread, a natural bee product, on testicular oxidative stress, inflammation and apoptosis, as well as lactate transport in the testis of high-fat diet (HFD)-induced obese rats. Adult male Sprague-Dawley rats were either fed with normal chow (NC), HFD, HFD + bee bread (0.5 g/kg b.w./day) or HFD + orlistat (10 mg/kg b.w./day) for 12 weeks. Our results show significant decreases in the activities and mRNA expression of antioxidant genes (Nrf2, Sod, Cat and Gpx), with significant increase in pro-inflammatory (Nf-κb, Tnf-α, iNos, Il-1β) and pro-apoptotic (p53, Bax, Bax/Bcl2, Caspase-8, Caspase-9 and Caspase-3) genes in the testis of HFD group relative to the NC group. Furthermore, proliferating cell nuclear antigen (PCNA) was poorly expressed in the testis of the HFD group relative to the NC group. Similarly, the mRNA levels of glucose transporters (Glut1 and Glut3), monocarboxylate transporters (Mct2 and Mct4) and lactate dehydrogenase type C (Ldhc) decreased significantly, with decrease in lactate utilisation. Treatment with bee bread upregulated testicular antioxidant enzymes, downregulated inflammation and apoptosis, and increased PCNA immunoexpression, in addition to improving lactate transport. Taken together, our results suggest that bee bread is a promising natural product with the potential to improve male fertility.

Introduction: Ethics education in surgical residencies is often delivered in an informal and nonstructured manner as part of a "hidden curriculum", leading to few residencies routinely including it in their core curriculum. This systematic review aimed to summarize the delivery modes, curriculum, structure, and effectiveness of ethics educational interventions for surgical trainees., Methods: We performed a comprehensive database search including MEDLINE, Embase, Scopus and CENTRAL to search for articles describing the implementation of ethics educational interventions for general surgery or subspecialty trainees., Results: A total of 14 studies were included. Only 2 centers performed targeted needs assessment. Curricula covered included informed consent, the doctor-patient relationship, breaking bad news, decision-making, end-of-life care, conflicts of interest, considering patients' personal contexts, and surgical research ethics. Modes of delivery varied across studies, including case-based learning, group discussions, didactic lectures, reading material, role-playing, simulated patients, and ethics morbidity and mortality (M&M) meetings. Evaluations were most commonly via surveys exploring knowledge and self-reported confidence, with only 3 studies measuring actual trainee performance using objective structured clinical examinations. In general, the educational interventions increased trainees' confidence/preparedness in handling ethical dilemmas., Conclusion: We recommend comprehensive local needs assessment to guide curricular development and designing specific learning objectives and measurable milestones to ensure evaluation. Educational interventions are best delivered in a graduated manner with the complexity of the topic mirroring residents' real-life clinical responsibilities and experiences. Teaching modalities should be tailored according to the nature of the curricular content being taught to make the learning experience more interactive and effective., (Copyright © 2023 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.)

This study analyzes the relationship between clean and dirty energy sources and energy metals during the COVID-19 pandemic. We document a sharp increase in connectedness after the COVID-19 pandemic, that is asymmetric at the lower and upper quantiles, with stronger dependence among the variables at the upper quantiles. Among the energy metals, cobalt is the least connected to the energy markets. Finally, our empirical results show a switch in the net connectedness indexes of energy metals and clean energy after January 2021. Our results have implication for investors and policy makers for energy and metal under various market conditions., (© 2022 Elsevier B.V. All rights reserved.)

This study examines the dynamic connectedness between COVID-19 media coverage index (MCI) and ESG leader indices. Our findings provide evidence that MCI plays a role in facilitating the transmission of contagion to advanced and emerging equity markets during the pandemic. The connectedness between MCI and ESG leader indices is more pronounced around March and April 2020 at the peak of the pandemic. The US is a net receiver of shocks reaffirming that it was the most affected country during the pandemic. Our results provide implications for investors, portfolio managers, and policymakers in mitigating financial risks during the pandemic., (© 2021 Elsevier Inc. All rights reserved.)

We explore the impact of the COVID-19 pandemic on the term structure of interest rates. Using data from developed and emerging countries, we demonstrate that the expansion of the disease significantly affects sovereign bond markets. The growth of confirmed cases significantly widens the term spreads of government bonds. The effect is independent of government policy and monetary responses to COVID-19 and robust to many considerations., (© 2021 Elsevier Inc. All rights reserved.)

We apply wavelet analyses to examine the impact of the Covid-19 fueled panic on the volatility of major fiat and cryptocurrency markets during January-May, 2020. There is high coherence between moves of the Coronavirus Panic Index and the price moves in Euro, British pound, and Renminbi currencies as well as movements of the Bloomberg Galaxy Crypto Index. The main conclusions for each index pair are quite similar and corroborate with our thesis that the cross-currency hedge strategies, which could work under normal market conditions, are likely to fail during the periods of global crisis, e.g., such as the Covid-19 pandemic. However, we document some important differences in currency markets behavior, which potentially could be used to design effective cross-currency hedges capable of withstanding adverse impacts of global financial and economic turmoil. Our findings could be of use for future development of financial policies and currency markets regulation rules., (© 2020 Elsevier B.V. All rights reserved.)