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Particulate matter (PM) is among the deadliest air pollutants due to its negative health impacts and environmental harm. This study reports on monthly and seasonal concentrations of PM10, PM2.5, and PM1, along with their ratios. Twelve-day samples were collected once a month in Mingora city (Swat, Pakistan) from January to December 2019 using a low volume sampler. Maximum average mass concentrations of PM10, PM2.5, and PM1 were recorded in December having values of 78, 56, and 32 μg m−3, respectively. Minimum average values for PM10 (44 μg m−3) and PM2.5 (25.1 μg m−3) were recorded in April, while the lowest PM1 (11 μg m−3) was recorded in August. In comparison to other months, the maximum average mass concentrations were 1.77 times (PM10), 2.23 times (PM2.5), and 2.9 times (PM1) higher in December. During the winter season, average mass concentrations remained high. Substantial correlation coefficients of 0.92, 0.79, and 0.75 were recorded between PM10 and PM2.5, PM2.5 and PM1, and PM2.5 and PM1, respectively. The overall average ratios PM2.5: PM10, PM1: PM2.5, and PM1: PM10 were 68.3, 52.6, and 35.4%, respectively. A moderate negative correlation of PM10, PM2.5, and PM1 with wind speed (−0.34, −0.39, and −0.41), a strong negative correlation with temperature (−0.69, −0.71, and −0.74) and rainfall (−0.63, −0.61, and −0.59), and a weak relationship with relative humidity (−0.32, −0.1, and −0.02) were recorded. [ABSTRACT FROM AUTHOR]

Objective: To assess the pattern of injuries in autopsy examination of road traffic accident cases at Peshawar. Material and Methods: A community-based descriptive cross-sectional study included a total of 94 candidates presented for autopsy at the forensic medicine department, Khyber medical college from 01st July 2020 to 30th June 2021. Results: The age of the subjects ranged from 2-80 years with a mean age of 36.9 ± 20.7 years. 96.8 % of subjects were having multiple injuries whereas, 3.2% were having a single injury. Overall, 94 cases had a total number of 303 injuries, out of which 90.76% were small-sized, 7.92% were medium-sized and 1.32% were large-sized including all kinds of injuries. The most common presenting injury was laceration (87.2%), preceded by abrasion (59.6%), then contusion (51.1%), fracture (23.4%), and hematoma (2.1%). The most common region involved in RTA was head & neck with 86.17%. Maximal deaths occurred within 3-6 hours following an RTA. The most common cause of death was an injury to the brain and its associated vessels. There is no significant correlation noted between the patterns of injury and the cause of death of subjects (p<0.05). Conclusion: Our study shows the pattern of injuries and causes of death via RTA, as there is no study conducted in this region. It will be useful to Law Enforcement agencies in implementing rules and regulations in preventing RTA and public awareness. [ABSTRACT FROM AUTHOR]

Exchange rates are crucial in regulating the foreign exchange market's dynamics. Because of the unpredictability and volatility of currency rates, the exchange rate prediction has become one of the most challenging applications of financial time series forecasting. This study aims to build and compare the accuracy of various methods. The time series model Auto-Regressive Integrated Moving Average (ARIMA) and Generalized Auto-Regressive Conditional Heteroscedasticity (GARCH) are utilized to forecast the daily US dollar to Pakistan rupee currency exchange rates (USD/PKR). Lagged observations of the data series and moving average technical analysis are used in both models. Explanatory factors were used as indicators, and the prediction performance was assessed using a variety of commonly known statistical metrics. These statistical metrics suggested the presence of conditional heteroscedasticity. Thus, the process turns to capture the volatility effect of conditional heteroscedasticity through GARCH modeling. It may be inferred based on the results of tentative models; that the ARCH model outperforms the GARCH model in terms of predicting the USD/PKR exchange rate. [ABSTRACT FROM AUTHOR]

Background: Essential Proteins are demonstrated to exert vital functions on cellular processes and are indispensable for the survival and reproduction of the organism. Traditional centrality methods perform poorly on complex protein–protein interaction (PPI) networks. Machine learning approaches based on high-throughput data lack the exploitation of the temporal and spatial dimensions of biological information. Results: We put forward a deep learning framework to predict essential proteins by integrating features obtained from the PPI network, subcellular localization, and gene expression profiles. In our model, the node2vec method is applied to learn continuous feature representations for proteins in the PPI network, which capture the diversity of connectivity patterns in the network. The concept of depthwise separable convolution is employed on gene expression profiles to extract properties and observe the trends of gene expression over time under different experimental conditions. Subcellular localization information is mapped into a long one-dimensional vector to capture its characteristics. Additionally, we use a sampling method to mitigate the impact of imbalanced learning when training the model. With experiments carried out on the data of Saccharomyces cerevisiae, results show that our model outperforms traditional centrality methods and machine learning methods. Likewise, the comparative experiments have manifested that our process of various biological information is preferable. Conclusions: Our proposed deep learning framework effectively identifies essential proteins by integrating multiple biological data, proving a broader selection of subcellular localization information significantly improves the results of prediction and depthwise separable convolution implemented on gene expression profiles enhances the performance. [ABSTRACT FROM AUTHOR]

Sidr honey is vulnerable to adulteration with low-grade honey and sugar syrups, which compromises its nutritional and medicinal value, demanding fast and reliable analytical tools for quality assessment. In this study, fluorescence spectroscopy was employed to assess the quality of a honey samples, specifically, Sidr, unifloral (Acacia) and multifloral (Acacia, Carisa and Justicia) honey. Fluorescence spectroscopy revealed characteristic spectral signatures of Sidr honey, compared to Acacia and multifloral honey. In addition, cane sugar syrup was artificially added to Sidr honey at different concentrations. These spectral signatures were exploited for the machine-assisted classification of Sidr, sugar syrup and different concentrations of Sidr–sugar mixture. The bagging classification algorithm generated values of sensitivity and specificity close to unity, indicating its ability for efficient discrimination of the samples. Fluorescence spectroscopy in tandem with chemometrics could potentially be used as a rapid analytical tool to identify Sidr honey and its sugar adulteration. [ABSTRACT FROM AUTHOR]

A field survey was conducted in rice-wheat cropping system of Gujranwala zone, Pakistan during Kharif season 2020 to estimate the economic viability and profitability analysis of mechanically transplanted rice (MTR) in comparison to conventional manual transplanting (CT). Convenience and snow-ball non probability sampling method was used due to less adoption rate of MTR with a sample size of 240. Among targeted MTR growers 72% had 6-row riding type mechanical transplanters (MT), 18% had 4-row walk after type MT and 10% had 8-row riding type MT. Super Basmati and PK 386 were found more adopted varieties with 47% and 38% share of rice area. An 11-13% improved yield and 16-20% more net returns estimated with MTR by acquiring required plant population in the field despite of paying 6.17% more operational cost for sowing and transplanting nursery. For service users of MT on rental basis the 292-303 values (variety wise) of marginal rate of returns (MRR%) was calculated. The project appraisal method of financial analysis illustrated the viability of MTR from the owner user or service provider's point of view as calculated by the indicators like benefit cost ratio, net present value, internal rate of return, payback period (yr) and breakeven point (ha yr-1). Hence, the adaptation of MTR would give farmers the opportunity to increase the productivity of rice crop and their farm income by coping the issues like labor scarcity, less plant population, delay in transplanting with more aged nursery, improper fixation of nursery plants in the soil etc. The study results projected mechanically transplanting area (ha) for riding type MT as well as for walk after type MT respectively as 64.78 and 28 annually. Accordingly, there would be 36.15 (000 ha) mechanically transplanted area (5.41%) of province Punjab, Pakistan annually after completion of the Govt. prevailing project on rice. [ABSTRACT FROM AUTHOR]

The development of three-dimensional (3D) hybrid organic–inorganic perovskites has sparked much interest because of their rich light-harvesting capabilities in solar cells. However, the understanding of the electronic and optical properties, particularly the excitonic shifts upon structural phase transition with temperature in these materials, is not fully clear. Here, we report the accurate description of electronic and optical properties of mostly studied FAPbI3 across the cubic–tetragonal–hexagonal phases, using the relativistic GW method and Bethe–Salpeter Equation (BSE), including the spin–orbit coupling effects. Our GW calculations reveal that the bandgap values vary from 1.47 to 3.54 eV from the room temperature cubic phase to the low temperature hexagonal phase. Our optical analysis shows that excitonic peaks are blue-shifted, and exciton binding energies estimated by the model BSE approach increase from 74 to 567 meV going from the cubic to hexagonal phases. Our results may have important impacts on the practical uptake of hybrid perovskite based solar cells under different climatic conditions. [ABSTRACT FROM AUTHOR]

Social distancing is crucial to restrain the spread of diseases such as COVID-19, but complete adherence to safety guidelines is not guaranteed. Monitoring social distancing through mass surveillance is paramount to develop appropriate mitigation plans and exit strategies. Nevertheless, it is a labor-intensive task that is prone to human error and tainted with plausible breaches of privacy. This paper presents a privacy-preserving adaptive social distance estimation and crowd monitoring solution for camera surveillance systems. We develop a novel person localization strategy through pose estimation, build a privacy-preserving adaptive smoothing and tracking model to mitigate occlusions and noisy/missing measurements, compute inter-personal distances in the real-world coordinates, detect social distance infractions, and identify overcrowded regions in a scene. Performance evaluation is carried out by testing the system's ability in person detection, localization, density estimation, anomaly recognition, and high-risk areas identification. We compare the proposed system to the latest techniques and examine the performance gain delivered by the localization and smoothing/tracking algorithms. Experimental results indicate a considerable improvement, across different metrics, when utilizing the developed system. In addition, they show its potential and functionality for applications other than social distancing. [ABSTRACT FROM AUTHOR]

The Claus process is one of the promising technologies for acid gas processing and sulfur recovery. Hydrogen sulfide primarily exists as a byproduct in the gas processing unit. It must be removed from natural gas. The Environmental Protection Agency (EPA) notices that increasing SO2 and CO2 in the air harms the environment. Sulfur generally has an elemental content of 0.1–6 wt % in crude oil, but the value could be higher than 14% for some crude oils and asphalts. It produces SO2 and CO2 gases, which damage the environment and atmosphere of the earth, called primary pollutants. When SO2 gas is reacted with water in the atmosphere, it causes sulphur and nitric acid, called a secondary pollutant. The world countries started desulphurization in 1962 to reduce the amount of sulfur in petroleum products. In this research, the Claus process was modeled in Aspen Plus software (AspenTech, Bedford, MA, USA) and industrial data validated it. The Peng–Robinson method is used for the simulation of hydrocarbon components. The influence of oxygen gas concentration, furnace temperature, the temperature of the first catalytic reactor, and temperature of the second catalytic reactor on the Claus process were studied. The first objective of the research is process modeling and simulation of a chemical process. The second objective is optimizing the process. The optimization tool in the Aspen Plus is used to obtain the best operating parameters. The optimization results show that sulfur recovery increased to 18%. Parametric analysis is studied regarding operating parameters and design parameters for increased production of sulfur. Due to pinch analysis on the Claus process, the operating cost of the heat exchangers is reduced to 40%. The third objective is the cost analysis of the process. Before optimization, it is shown that the production of sulfur recovery increased. In addition, the recovery of sulfur from hydrogen sulfide gas also increased. After optimizing the process, it is shown that the cost of heating and cooling utilities is reduced. In addition, the size of equipment is reduced. The optimization causes 2.5% of the profit on cost analysis. [ABSTRACT FROM AUTHOR]

Reducing cadmium (Cd) bioavailability and rhizobacterial Cd mobilization functions in the rhizosphere via the inoculation of screened microbial inoculum is an environmental-friendly strategy to improve safety of crop grains. In this study, Bacillus Cereus , a model Cd resistant strain, was selected to explore its effects on Cd bioavailability and uptake, bacterial metabolic functions related to Cd mobilization. Results indicated that inoculation of Bacillus Cereus in maize roots of sand pot with water-soluble Cd (0.06–0.15 mg/kg) and soil pot with high Cd-contaminated soil (total Cd: 2.33 mg/kg; Cd extracted by NH 4 NO 3 : 38.6 μg/kg) could decrease water-soluble Cd ion concentration by 7.7–30.1% and Cd extracted with NH 4 NO 3 solution by 7.8–22.5%, inducing Cd concentrations in maize grains reduced by 10.6–39.9% and 17.4–38.6%, respectively. Even for a single inoculation in soil, Cd concentration in maize grains still satisfy food safety requirements (Cd content: 0.1 mg/kg dry weight) due to its successful colonization on root surface of maize. Bacillus Cereus could enrich more plant growth promotion bacteria (PGPB) and down-regulate the expression of genes related to bacterial motility, membrane transports, carbon and nitrogen metabolism in the rhizosphere soil, decreasing Cd bioavailability in soil. Approximately 80% Cd2+ in media was transferred into intracellular, meanwhile Cd salts (sulfide and/or phosphate) were produced in Bacillus Cereus through biomineralization process. Overall, this study could provide a feasible method for improving safety of maize grains via the inoculation of Bacillus Cereus under Cd pollution. [Display omitted] • Bacillus Cereus decreases water soluble Cd concentration by 8–30% in sand pot. • Single inoculation can ensure grains safety of maize in high Cd-contaminated soil. • Bacillus Cereus inhibits expression of rhizobacterial genes related to Cd mobilization. • Cadmium salts (Cd-S, Cd-P etc.) were formed with via biomineralization in medium. [ABSTRACT FROM AUTHOR]

The conventional teleportation protocol requires a state entangled in only one degree of freedom (DOF), while hyperteleportation requires more than single DOF to complete the task. The hyperteleportation schematics are demonstrated only for the photonic systems, where in the present paper we extend the idea to a hyperteleportation protocol involving the atomic internal and external states. The protocol is deterministically engineered through resonant and off-resonant atomic Bragg diffraction involving two-level neutral atoms under standard cavity-QED working environment. Moreover, the longer interaction time Bragg’s regime with well separated transverse momenta states as an output of the neutral atoms guarantees the high enough engineering fidelities with reduced decoherence rates. The experimental parameters for the demonstration of the proposed scheme are also elucidated briefly describing the optimistic feasibility for the experimental execution of the proposed schematics. [ABSTRACT FROM AUTHOR]

Objectives. Spinal cord injury (SCI) is defined as damage to spinal cord that result in loss of sensory, motor and autonomic function. With advancement in medical profession, it is reported that the death rate of SCI patients decreases, and patients survive after initial injury therefore, problem extends beyond patients to their family members. Caregiver is responsible to provide emotional, physical and functional support. As a result, burden on caregivers increases, which not only affected them physically but mentally as well. In this study we aimed to find out the mental burden among caregivers of spinal cord injured patients. Methods. Census was conducted among caregivers of SCI patients in paraplegic centre, Peshawar. Data was collected from 80 participants/caregivers, included both male and female. Zarit burden interview scale was used to gather data regarding mental burden from caregivers of SCI patients. SPSS version 25 was used for data analysis. Outcomes. In this study the number of participants who responded to this survey was 80 out of 86 participants. Among these 80 participants, 59 (73.75%) were male while 21 (26.25%) were female with mean age of 31.83 ± 12.050. Participants experienced different intensities of mental burden (11.3% no or little burden, 31.3% mild to moderate, 45% moderate to severe and 12.5% had severe burden. Response to question 3, 4, 20 and 21 was quite different from other questions in questionnaire. Significant difference between means of male and female caregivers regarding mental burden was calculated (p = 0.030). No significant difference between age and total score obtained was found (p = 0.116). Conclusions. Caregivers of SCI patients had moderate to severe level of burden. Response to certain questions in questionnaire was quite different from others. There was significant difference between means of male and female caregivers regarding mental burden and no significant difference between age and total score obtained was found in caregivers of SCI patients. [ABSTRACT FROM AUTHOR]

Pathogens integrate multiple environmental signals to navigate the host and control the expression of virulence genes. In this process, small regulatory noncoding RNAs (sRNAs) may function in gene expression as post-transcriptional regulators. In this study, the sRNA Xonc3711 functioned in the response of the rice pathogen, Xanthomonas oryzae pv. oryzicola (Xoc), to oxidative stress. Xonc3711 repressed production of the DNA-binding protein Xoc_3982 by binding to the xoc_3982 mRNA within the coding region. Mutational analysis showed that regulation required an antisense interaction between Xonc3711 and xoc_3982 mRNA, and RNase E was needed for degradation of the xoc_3982 transcript. Deletion of Xonc3711 resulted in a lower tolerance to oxidative stress due to the repression of flagella-associated genes and reduced biofilm formation. Furthermore, ChIP-seq and electrophoretic mobility shift assays showed that Xoc_3982 repressed the transcription of effector xopC2, which contributes to virulence in Xoc BLS256. This study describes how sRNA Xonc3711 modulates multiple traits in Xoc via signals perceived from the external environment. Author summary: Small, stable RNA species perform diverse functions in both prokaryotes and eukaryotes. In this study, the sRNA Xonc3711 decreased the production of DNA-binding protein Xoc_3982 in the bacterium Xanthomonas oryzae pv. oryzicola (Xoc) by base pairing with the xoc_3982 transcript. When Xonc3711 was mutated, Xoc was impaired in its ability to form flagella and produce biofilms, which reduced Xoc tolerance to oxidative stress. We also discovered that the DNA-binding protein Xoc_3982 represses the expression of xopC2, which encodes an effector protein, and reduces its expression. Our results show that Xonc3711 modulates and integrates multiple systems in Xoc to protect cells from oxidative damage. [ABSTRACT FROM AUTHOR]

This article investigates the existence and viability of some traversable wormholes involving electric charge effects in f (R , T) gravity. We use the negative energy density obtained from the Casimir source in this regard, and the consequences of the electromagnetic field produced by an electric charge are taken into account. In order to obtain wormhole shape function, we apply some noteworthy Casimir energy density systems like two parallel plates, two parallel cylinders, two spheres that are placed far apart, and the generalized uncertainty principle (GUP) correction. We analyze the fundamental wormhole conditions as well as the validity of null energy condition by taking variations of coupling parameter λ of f (R , T) gravity and the electric charge Q. Next, we explore the dynamics of gravitational active mass of the formulated wormhole solutions depending on Q. Furthermore, we study the volume integral quantifier of these charged Casimir wormhole solutions and also, determine the corresponding values of complexity factor. It is shown that the obtained wormhole solutions exhibit valid behavior and the respective values of complexity factor always fall within a certain range. [ABSTRACT FROM AUTHOR]

Ancylobacter pratisalsi sp. nov. strain E130T is a Gram-negative, nonmotile, aerobic, and rod-shaped bacterium that was recently isolated from the rhizosphere of Plantago winteri Wirtg. from a natural salt meadow. This strain was described as novel species in genus Ancylobacter; however, information about its complete genome has yet not been reported. In this study, its genome was completely sequenced by PacBio SMRT cell platform, analyzed, and compared with other selected complete genome sequences of Ancylobacter to elucidate its potential plant growth promotion abilities. The genomic analysis revealed that the genome of strain E130T consists of one circular DNA chromosome of 4,618,530 bp with a GC content of 66% and one plasmid of 159,741 bp with a GC content of 64.13%. The entire genome contains 4,322 predicted coding genes, 49 transfer RNAs, and 6 ribosomal RNA genes. Genome analysis identified a siderophore natural product biosynthesis cluster, which produces fuscachelin. Knockout of several key genes in this cluster significantly reduces the plant-growth-promotion ability of the strain E130T. In addition to plant-growth promotion, the strain E130T can grow well on 5% NaCl (wt/vol), indicating that this strain is a potential bioresource for successful production of economic crops in alkaline soil. [ABSTRACT FROM AUTHOR]

Magnesium ion batteries (MIBs) are one of the vital strategies for the next-generation energy needs and computational simulations can accelerate this search many folds. In this paper, we suggest a novel cathode material, quinone functionalized hexahydroxytriphenylene (HHTP) and diphenylbutadiynebis (boronic acid) (DPB) based porous polymer (QHHTP-DPB), for Mg-ion batteries. The material is stable with highly porous structure and strong affinities for Mg ions to attach to C=O sites of the quinone rings. The single unit of the polymer layer can be fully loaded with Mg ions at various active sites exhibiting a specific theoretical-capacity of 720.48 mAhg−1 and positive low open-circuit voltage of 0.39 V. No structural variation is observed in QHHTP-DPB and a larger decrease in the HOMO-LUMO gap occurs after Mg ions adsorption onto the polymer, reflecting the better cycling performance and high capacity for Mg ion batteries. These results show that our designed quinone functionalized HHTP-DPB porous polymer could be a futuristic cathode material for MIBs and needs further theoretical and experimental investigations. [Display omitted] • QHHTP-DPB based porous polymer is studied for Mg-ion batteries. • The QHHTP-DPB polymer significantly stored a maximum of 10 Mg ions. • The QHHTP-DPB has high specific capacity of 720.48 mAh/g. [ABSTRACT FROM AUTHOR]

[Display omitted] • Benzoquinone-based microporous polymer is designed as cathode for magnesium-ion batteries that exhibits high stability. • Strong anchoring capability of magnesium ions with polymer have larger binding energies. • The polymer has high storage capacity i.e. twelve Mg ions without any structure distortion/volume change. • The material has high specific capacity of 467.038 mAh/g versus previously reported cathode materials for magnesium-ion batteries. Rechargeable magnesium-ion batteries (MIBs) can fulfill large-scale energy storage needs due to the abundance of Mg but technical challenges due to complexity of its chemistry results uncertainties about their commercialization. We for the first report benzoquinone-based microporous conjugated polymer (BQMCP) as cathode material for MIBs using density functional theory. It is dynamically and thermodynamically stable with a strong affinity for Mg-ions. The Mg ions strongly attaches to the C O group (redox-active sites) than π-bonds of BQMCP. The binding energy demonstrates that the interaction of the 2 Mg-ion system (BE = −47.32 kcal.mol−1) is stronger than the mono-Mg ion system (BE = −39.57 kcal.mol−1). The attachment of first Mg2+ to the BQMCP facilitate the attachment of another Mg ion. The BQMCP shows higher positive redox potential, which decreases with the increase of Mg atoms with the high storage capacity of twelve Mg ions/ BQMCP unit at redox-active sites without any structure distortion. Mg ions successfully entraps in bulk porous stacked BQMCP layers with higher negative binding energy values. The results demonstrates that the BQMCP is a promising cathode material for magnesium ion batteries in future. [ABSTRACT FROM AUTHOR]

In this work, spin-polarized density functional theory calculations are conducted to evaluate the possible applicability of a single Si atom doped boron nitride graphyne-like nansoheet (Si@BN-yne) for reduction of nitrous oxide (N 2 O). The calculations show that Si-doping in BN graphene is energetically favorable, and the resulting Si@BN-yne is both dynamically and thermodynamically stable. According to our findings, N 2 O spontaneously dissociates when it interacts with the Si@BN-yne from its O site without the need for an energy barrier, releasing 2.89 eV of energy. The adsorption energy of CO molecule on the Si@BN-yne is less negative than that of N 2 O, implying that N 2 O will predominately occupy the catalyst surface. The CO + O ad reaction is used to remove the remaining oxygen atom (O ad) from the Si@BN-yne surface. The calculations show that the reaction proceeds through a low energy barrier of 0.05 eV, which is much lower than the previously reported catalysts. This demonstrates the high catalytic activity of Si@BN-yne nanosheet. Furthermore, the adsorption of H 2 O and O 2 species on the Si@BN-yne nanosheet is investigated. The results show that the presence of these species has no effect on the catalytic activity of the Si@BN-yne for N 2 O reduction. These results show that the proposed novel Si@BN-yne catalyst can be regarded as an efficient material in the development of promising active catalysts for N 2 O elimination from the environment. [Display omitted] • Si-doping modifies the electronic structure of BN-yne. • N 2 O interacts weakly with the pristine BN-yne. • N 2 O dissociates spontaneously over Si@BN-yne. • The activation barrier for removing O ad from Si@BN-yne is 0.05 eV. [ABSTRACT FROM AUTHOR]

Application of strain is an important technique to tune the physical properties of materials and make them promising in renewable energy resources and nanoelectronics. Production of hydrogen from water splitting is a possible solution to the energy crises. Low cost and efficient photocatalyst is highly desired to be explored. Through first principle investigation the electronic properties, band alignment and the photocatalytic response of GaN-MoSSe and GaN-WSSe heterostructures are calculated. Different stacking of the materials are modeled and from relaxation energies the most stable material is investigated. Type-II band alignments are confirmed in these heterostructures. Switching of band alignment from type-II to Type-III is predicted in GaN-MoSSe with compressional strain. The photocatalytic behavior of these systems based on valence and conduction band edge potentials confirms that GaN-WSSe is energetically favorable at pH ​= ​0 for water splitting. [Display omitted] • Theoretical investigation of GaN-MSSe (M ​= ​Mo, W) van der Waals heterostructures is performed by DFT calculations. • These van der Waals heterostructures are found to be energetically stable. • GaN-MSSe (M ​= ​Mo, W) exhibit indirect band gap nature. • Type-II band alignment is observed through PBE calculations in these materials. • GaN-WSSe is energetically favorable for water splitting. [ABSTRACT FROM AUTHOR]

The current study investigates the variation and physicochemical properties of ambient particulate matter (PM) in the very important location which lies in the foothills of the Hindu Kush ranges in northern Pakistan. This work investigates the mass concentration, mineral content, elemental composition and morphology of PM in three size fractions, i.e., PM1, PM2.5 and PM10, during the year of 2019. The collected samples were characterized by microscopic and spectroscopic techniques like Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy and scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDX) spectroscopy. During the study period, the average temperature, relative humidity, rainfall and wind speed were found to be 17.9 °C, 65.83%, 73.75 mm and 0.23 m/s, respectively. The results showed that the 24 h average mass concentration of PM10, PM2.5 and PM1 were 64 µgm−3, 43.9 µgm−3 and 22.4 µgm−3, respectively. The 24 h concentration of both PM10 and PM2.5 were 1.42 and 2.92 times greater, respectively, than the WHO limits. This study confirms the presence of minerals such as wollastonite, ammonium sulphate, wustite, illite, kaolinite, augite, crocidolite, calcite, calcium aluminosilicate, hematite, copper sulphate, dolomite, quartz, vaterite, calcium iron oxide, muscovite, gypsum and vermiculite. On the basis of FESEM-EDX analysis, 14 elements (O, C, Al, Si, Mg, Na, K, Ca, Fe, N, Mo, B, S and Cl) and six groups of PM (carbonaceous (45%), sulfate (13%), bioaerosols (8%), aluminosilicates (19%), quartz (10%) and nitrate (3%)) were identified. [ABSTRACT FROM AUTHOR]

In order to reduce the hemodialysis cost and duration, an investigation of the effect of dialyzer design and process variables on the solute clearance rate is required. It is not easy to translate the in vivo transfer process with in vitro experiments, as it involves a high cost to produce various designs and membranes for the dialyzer. The primary objective of this study was the design and development of a computational tool for a dialyzer by using a computational fluid dynamic (CFD) model. Due to their complexity, only researchers with expertise in computational analysis can use dialyzer models. Therefore, COMSOL Inc. (Stockholm, Sweden) has made an application on membrane dialysis to study the impact of different design and process parameters on dialyzed liquid concentration. Still, membrane mathematical modeling is not considered in this application. This void hinders an investigation of the impact of membrane characteristics on the solute clearance rate. This study has developed a stand-alone computational tool in COMSOL Multiphysics 5.4 to fill this void. A review of the literature conducted shows that there are no suitable stand-alone computational tools for kidney dialysis. Very little work has been undertaken to validate the stand-alone computational tool. Medical staff in the hospitals require a computational tool that can be installed quickly and provide results with limited knowledge of dialysis. This work aims to construct a user-friendly computational tool to solve this problem. The development of a user-friendly stand-alone computational tool for the dialyzer is described thoroughly. This application simulates a mathematical model with the Finite Element Method using the COMSOL Multiphysics solver. The software tool is converted to a stand-alone version with the COMSOL compiler. The stand-alone computational tool provides the clearance rate of six different toxins and module packing density. Compared with the previous application, the stand-alone computational tool of membrane dialysis enables the user to investigate the impact of membrane characteristics and process parameters on the clearance rate of different solutes. The results are also inconsistent with the literature data, and the differences ranges are 0.09–6.35% and 0.22–2.63% for urea clearance rate and glucose clearance rate, respectively. Statistical analysis of the results is presented as mean with 95% confidence intervals (CIs) and p values 0.9472 and 0.833 of the urea and glucose clearance rates, respectively. [ABSTRACT FROM AUTHOR]

Surface plasmon (SP)—induced spectral hole burning (SHB) at the silver-dielectric interface is investigated theoretically. We notice a typical lamb dip at a selective frequency, which abruptly reduces the absorption spectrum of the surface plasmons polaritons (SPP). Introducing the spontaneous generated coherence (SGC) in the atomic medium, the slope of dispersion becomes normal. Additionally, slow SPP propagation is also noticed at the interface. The spectral hole burning dip is enhanced with the SGC effect and can be modified and controlled with the frequency and intensity of the driving fields. The SPP propagation length at the hole-burning region is greatly enhanced under the effect of SGC. A propagation length of the order of 600 µm is achieved for the modes, which is a remarkable result. The enhancement of plasmon hole burning under SGC will find significant applications in sensing technology, optical communication, optical tweezers and nano-photonics. [ABSTRACT FROM AUTHOR]

• Hybrid ant genetic algorithm for efficient task scheduling in cloud datacenter is proposed. • Reduces scheduling solution space. • Minimizes workflow execution time by load balancing. • Less response time than genetic algorithm. Cloud computing is a computing paradigm which meets the computational and storage demands of end users. Cloud-based data centers need to continually improve their performance due to exponential increase in service demands. Efficient task scheduling is essential part of cloud computing to achieve maximum throughput, minimum response time, reduced energy consumption and optimal utilization of resources. Bio-inspired algorithms can solve task scheduling difficulties effectively, but they need a lot of computational power and time due to high workload and complexity of the cloud environment. In this research work, Hybrid ant genetic algorithm for task scheduling is proposed. The proposed algorithm adopts features of genetic algorithm and ant colony algorithm and divides tasks and virtual machines into smaller groups. After allocation of tasks, pheromone is added to virtual machines. The proposed algorithm effectively reduces solution space by dividing tasks into groups and by detecting loaded virtual machines. Due to the minimum solution space of proposed algorithm, convergence and response time is significantly decreased. It finds a feasible scheduling solution to minimize the running time of workflows and tasks. The proposed algorithm achieved 64% decrease in execution time and 11% decrease in overall data center costs. [Display omitted] [ABSTRACT FROM AUTHOR]

In petroleum refineries, naphtha reforming units produce reformate streams and as a by-product, hydrogen (H2). Naphtha reforming units traditionally deployed are designed as packed bed reactors (PBR). However, they are restrained by a high-pressure drop, diffusion limitations in the catalyst, and radial and axial gradients of temperature and concentration. A new design using the fluidized bed reactor (FBR) surpasses the issues of the PBR, whereby the incorporation of the membrane can improve the yield of products by selectively removing hydrogen from the reaction side. In this work, a sequential modular simulation (SMS) approach is adopted to simulate the hydrodynamics of a fluidized bed membrane reactor (FBMR) for catalytic reforming of naphtha in Aspen Plus. The reformer reactor is divided into five sections of plug flow reactors and a continuous stirrer tank reactor with the membrane module to simulate the overall FBMR. Similarly, a fluidized bed reactor (FBR), without membrane permeation phenomenon, is also modelled in the Aspen Plus environment for a comparative study with FBMR. In FBMR, the continuous elimination of permeated hydrogen enhanced the production of aromatics compound in the reformate stream. Moreover, the exergy and economic analyses were carried out for both FBR and FBMR. [ABSTRACT FROM AUTHOR]

To tune the physical properties of a material for promising application in nanoelectronics and renewable energy sources, stacking of two dimensional materials via weak van der Waals interaction and application of strain are important techniques. The electronic properties and the band alignment in Janus transition metal dichalcogenides heterostructures are investigated by performing first principle calculations. Different stacking are modeled and the most stable stacking are confirmed through binding energy. All these heterostructures are confirmed to have type-I band alignment. Switching from type-I to type-II or type-III band alignment is observed with application of strain in these heterostructures. Semi classical Boltzmann transport theory is used to investigate thermoelectric parameters of these heterostructures. The high Seebeck coefficient of these heterostructures confirms that these materials are suitable for thermoelectric devices. We have stacked the layers of Janus transition metal diachalcogenides in different stacking order, and find the most stable stacking. The structure and electronic properties of the most stable heterostructures are then calculated. [Display omitted] • Strain effect on structural and electronic properties of MXY (M=Zr, Hf and Pt; X/Y=S, Se) vdW heterostructures. • These van der Waals heterostructures are found to be energetically stable. • Like their monolayers these heterostructures exhibit the indirect band gap nature. • Switching from type-I to type-II or Type-III band alignment is observed with the application of strain. • The thermoelectric response of these heterostructures is also reported. [ABSTRACT FROM AUTHOR]