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This study aimed to determine the effects of preharvest spraying of melatonin and postharvest immersion in xanthan gum on the quality and postharvest performance of Orlando tangelo mandarin fruits. After selecting suitable and uniform trees, melatonin foliar spraying was performed at three different concentrations: 0,100 μM, and 200 μM. Foliar spraying was performed one month before harvest and was repeated three times at weekly intervals. Furthermore, the fruits were immersed in two different concentrations of xanthan gum (0.1% and 0.2%) postharvest, these fruits were stored in a cold room at 5 ± 1 °C. Evaluation of fruit characteristics was carried out at the time of harvest and after 45 and 90 days of cold storage. The results showed that foliar spraying of melatonin at a concentration of 100 μM showed the highest weight and pulp of the fruit. Furthermore, melatonin treatment resulted in higher levels of ascorbic acid and increased fruit acidity compared to the control. During storage, fruits treated with melatonin and xanthan coatings showed better quality than those of the control. At the end of the experiment, the lowest weight loss was observed in fruits treated with 200 μM melatonin + 0.1% xanthan. The highest ascorbic acid content was observed in the 100 μM melatonin +0.1% xanthan. The maximum antioxidant activity was observed in 100 μM and 200 μM +0.1% xanthan and also 100 μM melatonin alone. In general, the findings suggest that preharvest foliar spraying and the postharvest application of xanthan coatings can be effective strategies for maintaining Orlando tangelo quality during cold storage.

Semiconductor photocatalysis has been extensively used in the degradation of pollutants and the production of hydrogen fuel. The main drawback in the application of semiconductor photocatalysis is the rapid recombination of charge carriers. Several strategies have been applied to improve charge carrier separation to preserve them for imparting in photocatalytic reactions. Among the modifications that are made in the photocatalytic systems, the construction of different types of heterostructures, including type II, Z‐scheme, p–n junction, and Schottky junction, has received great attention. Recently, emerging S‐scheme heterojunctions have been shown to be able to preserve powerful charge carriers for photocatalytic reactions, which is not the case in other heterostructures. In this review, principles and mechanisms of charge transfer in S‐scheme heterostructures are discussed, and important semiconductors that have been used in the construction of this type of heterojunctions are reviewed. Methods for identification of S‐scheme heterojunction, challenges, and prospects have been addressed. [ABSTRACT FROM AUTHOR]

Approximate deconvolution (AD) has emerged as a promising closure for large-eddy simulation in complex multi-physics flows, where the conventional pure dynamic eddy-viscosity (DEV) models experience issues. In this research, we propose novel improved mixed hard-deconvolution or secondary-regularization models and compare their performance with the existing standard mixed AD-DEV and penalty-term regularizations. For this aim, five consistency criteria, based on the properties of the modeled sub-filter-scale stress in limiting conditions, are introduced for the first time. It is proved that the conventional hard-deconvolution models do not adhere to a couple of important primary criteria. Furthermore, through a priori and a posteriori analyses of Burgers turbulence and turbulent channel flow, it is manifested that the inconsistency with the primary criteria can result in larger modeling errors, the over-prediction and pileup of kinetic energy in eddies of a length scale between the explicit filter width and grid size, and even the solution instability. On the other hand, the favorable characteristics of the new mixed models, in terms of the consistency criteria, significantly improve the accuracy of the predictions, the solution stability, and even the computational cost, particularly for one of the new models called mixed alternative-DEV (A-DEV). [ABSTRACT FROM AUTHOR]

Summary: Background: The use of combinations of α2‐adrenergic agonists and opioids has been published as providing superior sedation than either drug alone. Objectives: The present study aimed to compare the sedative and physiological effects of intravenous (IV) administration of dexmedetomidine alone and in combination with methadone, morphine, tramadol or pethidine in miniature donkeys. Study design: Experimental, crossover Latin square, randomised, blinded study. Methods: Twelve clinically healthy miniature donkeys with a mean age of 6 ± 2 (mean ± SD) years, weight of 94 ± 5 kg and height at withers of 0.80 ± 0.06 m were assigned to six IV treatments. They received either 0.9% saline, 5 μg/kg dexmedetomidine, 5 μg/kg dexmedetomidine and 0.2 mg/kg methadone, 5 μg/kg dexmedetomidine and 0.1 mg/kg morphine, 5 μg/kg dexmedetomidine and 2 mg/kg tramadol or 5 μg/kg dexmedetomidine and 1 mg/kg pethidine, with a washout period of 8 days. The degree of sedation was investigated using a numerical ranking scale of 0–3. Heart rate (HR), respiratory rate (RR), rectal temperature (RT) and intestinal motility were performed before and 5, 10, 15, 30, 45, 60, 75, 90 and 120 min after drug administration. Results: Animals in dexmedetomidine or dexmedetomidine/opioid treatments were sedated for 5–60 min. Sedation was significantly higher in dexmedetomidine/opioid treatments than in dexmedetomidine at 15–30 min (p < 0.05). In all treatments, HR and RR significantly decreased from baseline at 5–75 and 30–60 min, respectively (p < 0.05). Intestinal motility was decreased in dexmedetomidine and dexmedetomidine/opioid treatments at 5–60 and 5–90 min, respectively. Compared to dexmedetomidine, intestinal motility was significantly lower in dexmedetomidine/opioid treatments at 75–90 min. Main limitations: Assessment of only HR and RR are inadequate to describe the cardiorespiratory effects of dexmedetomidine/opioids. Conclusions: The use of combinations of dexmedetomidine/opioids would be considered for superior sedation for 15–30 min after administration in miniature donkeys. No significant differences were detected between opioids in combination with dexmedetomidine in miniature donkeys. [ABSTRACT FROM AUTHOR]

Poverty is one of the most important economic issues in developing countries such as MENA. Poverty causes many social problems such as drug trafficking, theft, prostitution and corruption. On the other hand, corruption is a major problem in developing countries. Corruption destroys resources as well as impedes the optimal allocation of resources. Statistics show that Iran is at a disadvantage both in terms of poverty and corruption. Therefore, considering the importance of fighting poverty and corruption, the main purpose of this study is to investigate the impact of poverty on corruption. The Human Development Index was used to measure poverty and the World Bank Corruption Control Index was used to measure corruption. The Bayesian Hierarchical method was used to estimate regression. The results showed that the variables of economic growth, and human development index have a negative impact and the variables of trade freedom index, foreign direct investment, and the share of government spending in GDP have a positive effect on corruption. [ABSTRACT FROM AUTHOR]

Calculating the entropy for complex systems is a significant problem in science and engineering problems. However, this calculation is usually computationally expensive when the entropy is computed directly. This paper introduces three classes of information sources that for all members of each class, the entropy value is the same. These classes are characterized according to special dynamics created by three kinds of self-mappings on Ω, and A, where Ω is a probability space and A is a finite set. An approximation of rank variables of the product of information sources is made, and it is proved that the topological entropy of the product of two information sources is equal to the summation of their topological entropies. [ABSTRACT FROM AUTHOR]

The introduction of 2D materials in recent years has resulted in an emerging type of constructed structure called van der Waals heterostructures (vdseWHs) that take advantage of the 2D materials in forming atomically thin components and devices. The vdWHs are constructed by the stacking of 2D materials by van der Waals interactions or edge covalent boning. The electron orbitals of the 2D layers in vdWHs extend to each other and influence the electronic band structures of the constituent layers. The tunable optical response over a wide range of wavelengths (NIR to visible) can be obtained by assembling vdWHs by combining the monolayers. By application of 2D layers in vdWHs, p-n heterojunctions without lattice mismatch can be formed. The photodiodes based on the van der Waals interactions could be considered promising candidates for future optoelectronic devices. Furthermore, on-chip quantum optoelectronics can move to the next generation by using 2D materials in vdWHs. In this review, the vdWHs are introduced and their properties and applications in light-emitting diodes (LEDs) have been discussed. The vdWHs allow bandgap engineering, and hence, LEDs working in a range of wavelengths can be realized. The applications of vdWHs in forming atomically thin components in optoelectronic devices and LEDs have been addressed. [ABSTRACT FROM AUTHOR]

Due to the anti-inflammatory and antioxidant properties of Scrophularia striata, it is used to heal wounds. Today, hydrogel based on alginate-polyethylene glycol polymer is mainly used due to its drug delivery properties and create of suitable conditions for wound healing. In this study, we tried to investigate the effect of hydrogel based on alginatepolyethylene glycol polymer containing Scrophularia striata extract nanoliposomes on wound healing in rat animal models. Field emission scanning electron microscopy and dynamic light scattering were used to examine nanoliposome and hydrogel. 126 Wistar albino rats were randomly divided into 7 groups (18 rats/group). The rats were anesthetized and their dorsum shaved, a burn wound was created with a cylindrical copper at 100° C. Rats' wounds were treated with hydrogel Scrophularia striata extract and on the 5th, 10th, and 15th days, histopathological evaluation, macroscopic features and wound healing were evaluated and analyzed in different groups. The structure of nanoliposomes was uniform and the size was 80-110 nm. Also, the size of the hydrogel was 320 nm with nanometric size and spherical morphology. Histopathological evaluation, wound area and wound contraction confirmed that the treatment group had a significant difference from other groups and the effect was almost similar to that of zinc oxide. This study showed that alginate-polyethylene glycol polymer containing Scrophularia striata extract caused wound contraction, and reduced wound area, and can be used for wound healing. [ABSTRACT FROM AUTHOR]