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In this work, WS 2 /CeO 2 heterostructured composite was synthesized to develop a highly active cathodic electrocatalyst in a microbial fuel cell (MFC). The layered structure and distinctive properties of WS 2 (semiconductor behavior, stability, tunable properties, superconductivity, etc.), coupled with the oxygen storage capabilities of CeO 2 , form the basis of this composite approach. Comprehensive characterization techniques confirmed the successful synthesis and highlighted the unique properties of the composite. Electrochemical analyses revealed the enhanced catalytic activity of the WS 2 /CeO 2 composite for ORR. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) studies demonstrated improved kinetics and current density compared to individual WS 2 and CeO 2 components. Electrochemical impedance spectroscopy (EIS) underscored the collaborative behavior of the composite, leading to improved charge transfer efficiency at the electrode-electrolyte interface. Practical application of the WS 2 /CeO 2 composite in a dual-chamber MFC revealed its potential for enhanced power generation and pollutant removal. The composite cathode exhibited superior performance in terms of power density (129.13 mW/m2), open-circuit voltage (609 mV), and chemical oxygen demand (COD) removal efficiency (76.6%) compared to conventional graphite cathodes. The efficient strategy of using the modified cathode, which exhibit excellent stability, high electric energy output, and simple fabrication, was proven to improve the overall performance of MFC. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of photo/electrocatalysts is an idea to simultaneously enhance power generation and pollutant degradation in a microbial fuel cell (MFC), which may improve its efficiency. Herein, a unique approach was taken to enhance the degradation efficiency of methylene blue (MB) by using a photo-assisted MFC technology with an Ag-2-methyl imidazole (mIm)/g-C 3 N 4 photocathode. Various physicochemical analyses were implemented to confirm the successful synthesis of the prepared samples. From the electrochemical analysis, the high current density (0.1 mA cm2) and the low charge transfer resistance were recorded for Ag-mIm/0.01 g-C 3 N 4 under light irradiation, which is more favorable for pollutants removal. Further investigation of the photo-assisted MFC with Ag-mIm/0.01 g-C 3 N 4 modified cathode revealed the maximum power density of 45.37 mW m2 under the light irradiation, which was 1.8 times higher compared with the dark state. The study demonstrated that the degradation efficiency of MB under light can achieve up to 69%, with an initial concentration of 30 mg L−1, after 72 h. This research suggested a promising process for further usage of MFCs in wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Providing an active learning environment and engaging students in classroom discussion could be quite challenging. This study used a quasi-experimental method to manipulate students' incentives for participation in group discussion to investigate its impact on students' learning outcomes. Two research methods courses taught over four years by the author were examined. Eighty samples of students' online discussions were recorded, transcribed, and analyzed to assess the impact of four different strategies on quantity, quality, and outcome of students' group discussions. The results showed significant differences in all aspects. The implications of the results for teachers who plan to use group discussion in their courses are discussed and suggestions for future research are offered. [ABSTRACT FROM AUTHOR]

A series of 1,4-dihydropyridine (DHP) derivatives have been synthesized and evaluated against both promastigote and amastigotes forms. All compounds showed higher activity than the reference drug amphotericin B. However, they exhibited less activity than the reference drug glucantime, except compound 4e. These compounds showed excellent anti-promastigote and amastigote activities in range of low nanomolar and low micromolar, respectively. Among the screened compounds, 4d was found as the most potent compounds against promastigote form with EC50 value of 0.0001 nM and compound 4e was the most potent compound against amastigote form with EC50 value of 2.38 µM. Based on CC50 results, synthesized compounds were found nontoxic to macrophages. The study demonstrated that, the position and nature of the substituents on phenyl ring of C4 in the DHP ring and the length of the chain belonging to the ester groups influences the biological activity of these compounds. Based on docking studies, it was proposed that compounds 4d and 4e form key interactions with regions of PTR1 enzyme. [ABSTRACT FROM AUTHOR]

Nowadays, many studies are conducted on multilayer hydrogels for wound dressing. On the other hand, considering the emergence of bacterial resistance to common antibiotics, studies on the use of natural essential oils and their derivatives that have antibacterial and antioxidant activity can be useful. Herein, a novel bilayer hydrogel developed from polyvinyl alcohol and chitosan with the incorporation of Saqez essential oil (SEO) was synthesized. The results showed a gel-type structure with specific compression and flexibility, while the microscopic images confirmed the formation of a bilayer hydrogel. Further, the data showed that increasing the concentration of SEO reduces the swelling and water vapor permeability and increases the water retention and hydrophobicity of the hydrogel surface. The effects of the combination of SEO in the bilayer hydrogel led to a strong antioxidant property and increased antimicrobial activity. Also, the in vitro results demonstrated that the bilayer hydrogels are biocompatible, non-toxic, and blood compatible. Finally, the results of the in vivo tests showed that these bilayer hydrogels had good homeostatic efficiency. Overall, the obtained results indicate that these bilayer hydrogels are promising candidates for wound dressing. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Meningitis is known as a meningeal inflammation accompanied by pleocytosis in the cerebrospinal fluid (CSF), and can be classified into acute, subacute, and chronic meningitis based on symptoms duration of ≤ 5 days, ≥ 5 days and ≥ 4 weeks, respectively. Subacute and chronic meningitis are caused mainly by indolent infectious agents and noninfectious causes such as autoimmune, and neoplastic. In this study, we investigated the characteristics, diagnosis, and treatment of subacute and chronic meningitis.Methods: We extracted the medical records of patients with chronic and subacute meningitis who were referred to three tertiary centers from Jun 2011 to Jun 2021. Initially, 2050 cases of meningitis were screened, and then 79 patients were included in the study.Results: Headache (87.3%), nausea and vomiting (74.7%), fever (56.4%), and visual impairments (55.7%) were the most prevalent symptoms. The most common signs were nuchal rigidity (45.3%), altered mental status (26.9%), and papillary edema (37.5%). Brain computed tomography (CT) was normal in 68.6% of the patients while 22.9% of the cases had hydrocephalus. Brain magnetic resonance imaging (MRI) was normal in 60.0% of the patients. The most common abnormal MRI findings were leptomeningeal enhancement (16.0%) and hydrocephalus (16.0%). We had a 44.3% definite diagnosis with bacterial (n:25, 31.6%) and neoplastic (n:8, 10.1%) being the most prevalent etiologies. Mycobacterium tuberculosis (60%) and Brucella spp. (12%) were the most prevalent bacterial pathogens.Conclusions: The most common etiologies include infectious, neoplastic, and immunologic. Due to insidious presentation and uncommon etiologies, establishing a proper diagnosis, and providing timely targeted treatment for patients with subacute and chronic meningitis remains a challenge for clinicians. [ABSTRACT FROM AUTHOR]

The main goal of hydraulic fracturing stimulation in unconventional and tight reservoirs is to maximize hydrocarbon production by creating an efficient stimulated reservoir volume (SRV) around the horizontal wells. To zreach this goal, a physics-based model is typically used to design and optimize the hydraulic fracturing process before executing the job. However, two critical issues make this approach insufficient for achieving the mentioned goal. First, the physics-based models are based on several simplified assumptions and do not correctly represent the physics of unconventional reservoirs; hence, they often fail to match the observed SRVs in the field. Second, the success of the executed stimulation job is evaluated after it is completed in the field, leaving no room to modify some parameters such as proppant concentration in the middle of the job. To this end, this paper proposes data-driven and global sensitivity approaches to address these two issues. It introduces a novel workflow for estimating SRV in near real-time using some hydraulic fracturing parameters that can be inferred before or during the stimulation process. It also utilizes a robust global sensitivity framework known as the Sobol Method to rank the input parameters and create a reduced-order (mathematically simple) model for near real-time estimation of SRV (referred to as DSRV). The proposed framework in this paper has two main advantages and novelties. First, it is based on a pure data-based approach, with no simplified assumptions due to the use of a simulator for generating the training and test dataset, which is often the case in similar studies. Second, it treats SRV generation as a rock mechanics problem (rather than a reservoir engineering problem with fixed fracture lengths), accounting for changes in hydraulic fracture topology and SRV changes with time. A dataset from the Marcellus Shale Energy and Environment Laboratory (MSEEL) project is used. The model's input parameters include stimulation variables of 58 stages of two wells. These parameters are stage number, step, pump rate and duration, proppant concentration and mass, and treating pressure. The model output consists of the corresponding microseismic (MS) cloud size at each step (i.e., time window) during the job. Based on the model, guidelines are provided to help operators design more efficient fracturing jobs for maximum recovery and to monitor the effectiveness of the hydraulic fracturing process. A few future improvements to this approach are also provided. [ABSTRACT FROM AUTHOR]

Cancer is one of the leading causes of mortality in the world. Unfortunately, the present anticancer chemotherapeutics display high cytotoxicity. Accordingly, the discovery of new anticancer agents with lower side effects is highly necessitated. This study aimed to discover an anticancer compound from Hemiscorpius lepturus scorpion venom. Bioactivity-guided chromatography was performed to isolate an active compound against colon and breast cancer cell lines. 2D electrophoresis and MALDI-TOF were performed to identify the molecule. A partial protein sequence was obtained by mass spectrometry, while the full-length was deciphered using a cDNA library of the venom gland by bioinformatics analyses and was designated as leptulipin. The gene was cloned in pET-26b, expressed, and purified. The anticancer effect and mechanism action of leptulipin were evaluated by MTT, apoptosis, and cell cycle assays, as well as by gene expression analysis of apoptosis-related genes. The treated cells displayed inhibition of cell proliferation, altered morphology, DNA fragmentation, and cell cycle arrest. Furthermore, the treated cells showed a decrease in BCL-2 expression and an increase in Bax and Caspase 9 genes. In this study, we discovered a new anticancer protein from H. lepturus scorpion venom. Leptulipin showed significant anticancer activity against breast and colon cancer cell lines. [ABSTRACT FROM AUTHOR]

Prominent equipment with a very high demand for fuels in refineries is the fired preheater of crude oil. There are two main reasons to investigate the energy usage of such fired heaters. First, this is essential to the economic value of the refinery process unit and second, this is located at the beginning of the process line, which causes inefficient performance or damage in downstream equipment if it is not tuned properly. This paper concentrates on the thermal modeling of a fired heater of crude oil to evaluate the effect of influential parameters on fuel consumption. As the number of variables is markedly high, and considering the complexity of thermal modeling, all equations in a code yield predefined heater efficiency. Results from the model show that the increase in heater size yields a decrease in efficiency. It was also found that with a constant dimension of the fired heater, change in the number of pipes is much less influential rather than more inexpensive ideas like increasing speed of the burning gas on reduction of the fuel consumption. In other words, it was found that a distance of 500–650 mm from the center to the center distance of the pipes is the optimal distance to reduce fuel consumption. [ABSTRACT FROM AUTHOR]

[Display omitted] • Conjugated oligoelectrolytes (COEs) enhance bio-Current production in MFCs. • DMIF+ stained cells exhibit excellent performance in bio-current production. • Tolerance of COEs stained cells to different concentrations was investigated. • COEs spiking cells facilitates EET process and boosts MFCs performances. The anode compartment, as an electron generation station, determines the power performance and contaminant removal in microbial fuel cell (MFC). However, the extracellular electron transfer (EET) process limits bioelectricity generation. In this work, the role of conjugated oligoelectrolytes (COEs) on catalyzing bacterial activity toward bio-current production was investigated. In this regard, two COEs, namely [4-[1-(3-methylimidazolium chloride)]butyl] ferrocene (MIF+) and Bis [4-[1-(3-methylimidazolium chloride)]butyl] ferrocene (BMIF+) were synthesized and the increases in anodic current output were probed through MFC device. The electrochemical analyses revealed excellent performance in bio-current production for BMIF+ stained cells. The tolerance threshold of COEs stained cells for different concentrations of COEs was investigated using chronoamperometry (CA) test. Additionally, the power performance of MFC exhibited the highest value of 115.46 mW m−2 for the BMIF+ stained cells in comparison with MIF+ stained cells (73.12 mW m−2) and unstained cells (25.8 mW m−2). The results demonstrated that spiking cells' membranes with COEs is a meaningful strategy to facilitate the EET process and produce bioelectricity. [ABSTRACT FROM AUTHOR]

Increasing powder layer thickness could undoubtedly raise the productivity of the laser powder bed fusion (LPBF) process. On the other hand, it may cause some microstructural side-effects, which in turn influence the mechanical properties of the final part. In this work, the effects of increasing powder layer thickness from 30 to 50 μm were studied on the microstructure, tensile, and creep life of LPBF Inconel 718 (IN718). Microstructural investigations were done by optical microscope, field emission scanning electron microscope, and electron backscatter diffraction. Tensile tests were conducted at room temperature as well as 650 ֯C, and stress-rupture tests were performed in standard incremental mode. The results showed that by using 66% thicker powder layers, the intercellular spacing increased from 480 to 1000 nm and diameter of columnar grains enlarged from 38.6 to 69.3 μm. Also, coarser intercellular particles precipitated in continuous form. These microstructural changes led to slight variations in tensile properties at both room and high temperatures. On the other side, significant changes were observed in the creep life of the samples produced with different layer thicknesses. It was discovered that although the specimens produced with 30 μm layer thickness had 0.82% lower relative density, they exhibited 1.7 times longer creep life compared to those fabricated by 50 μm powder layer thickness. Furthermore, fractography showed the lack-of-fusions(LOFs) were the main crack initiators during the tensile tests, while intergranular cracking due to coalescence of spherical cavities caused the high-temperature failure during creep. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cesium phosphomolybdate was used to modify the cathode of a microbial fuel cell. • The modified cathode catalysed the oxygen reduction reaction. • The modified cathode 1.5 times increased the power density of microbial fuel cell. • The modified cathode decreased the charge transfer resistance to 2.5 times less. • Modified cathode produced a considerably-more-stable voltage. The sluggish oxygen reduction reaction (ORR) is a significant hurdle against microbial fuel cell (MFC) performance. Polyoxometalates are excellent candidates to address this challenge because they have the potential of improving ORR efficiency. Here, cesium phosphomolybdate was successfully synthesized through a facile solid-state method and then used as an ORR catalyst on a graphite cathode in an MFC with sodium acetate as the substrate in the anolyte. The CV analysis demonstrated that modified graphite has two ORR peaks at −0.25, −0.5 V vs Ag/AgCl and a higher current density than the bare graphite. The MFC equipped with the modified cathode displayed a maximum power density of 64.73 mW m−2, higher than that obtained for bare graphite (42 mW m−2). COD removal efficiencies in MFCs with modified and bare graphite cathodes were 86.4% and 85%, respectively which are similar to or better than what is published in the literature. This study offers an efficient ORR catalyst in MFC applications helping in using organic wastewater as a fuel by converting the chemical energy into electricity. [ABSTRACT FROM AUTHOR]

Objective: The strong antioxidant activity of Commiphora mukul prompted us to conduct the present study to explore whether treatment with C. mukul extract (CME) would have any protective influence on sperm parameters, testosterone levels, and plasma glucose levels in streptozotocin (STZ)-induced diabetic rats. Methods: Male Wistar rats were randomly divided into four groups: control, control animals treated with CME, diabetic animals, and diabetic animals treated with CME. CME extract (300 mg/kg) was administered for 60 days by daily gavage. Diabetes was induced by an intraperitoneal injection of 50 mg/kg STZ. The epididymal sperm count, weight, motility, morphology, viability, and serum testosterone and glucose levels were determined. Results: In the diabetic animals, CME decreased blood glucose levels (p<0.05), increased the total sperm count (p<0.05), and decreased the proportion of sperm with abnormal morphology (p<0.05). Diabetes reduced sperm motility (p<0.001), and CME supplementation partially reversed this effect of diabetes (p=0.003). Furthermore, in diabetic animals, CME decreased the proportion of immotile sperm (p<0.001). In rats, diabetes caused a significant decrease (p<0.05) in serum testosterone levels (F[3, 28]=3.283, p=0.035), but treatment of diabetic animals with CME increased serum testosterone levels. Conclusion: The present study demonstrated that C. mukul possesses proandrogenic activity and exerts a beneficial effect on sperm parameters in diabetic rats. [ABSTRACT FROM AUTHOR]

In this paper, heat loss is precisely computed by a proposed code considering different climates. Estimating the costs of different central heating system, unit heaters were selected as the most feasible system. Finally, considering the heating capacity and unit heater's dimensions a computational fluid dynamics model was developed to find the optimized configuration of unit heaters in a typical greenhouse. Using this model, the required thermal load for a greenhouse based on the daily temperature of Arak city in 2017 was computed with a smart control system. It was found that savings in energy consumption were approximately 5447 m3 of natural gas each year. [ABSTRACT FROM AUTHOR]

In this paper we define an equivalence relation on the set of all possible geo- metrical models of M(n, k) containing n points in 3D Euclidean space having k distinct distances. We investigate the number of geometrical models for M(4, 2), M(5, 2) and M(6, 2) up to the mentioned equivalence relation. [ABSTRACT FROM AUTHOR]

The study aimed to predict the happiness of adolescents based on coping styles and religious attitudes. To this end, the correlational research methodology was used. In total, 381 subjects were selected from adolescents of Semnan (Eastern province of Iran), using multistage clustering sampling method. Research tools were Ways of Coping Questionnaire by Lazarus, Golriz and Barahani's Religious Attitude Questionnaire, and Oxford Happiness Questionnaire. Data analysis was performed in SPSS using Pearson's correlation coefficient and multiple regression analysis. Results of Pearson's correlation demonstrated a significant positive relationship between happiness of adolescents and variables of problem-focused coping styles (r = 0.31, P < 0.01) and religious attitudes (r = 0.129, P < 0.05). Meanwhile, a negative significant association was observed between emotion-focused coping styles and happiness (r = −0.184, P < 0.01). Moreover, results of multiple regression analysis indicated that the listed variables explained 17% of the variance of happiness in totality. According to the results, it is recommended that use of problem-focused styles be emphasized in addition to strengthening of religious attitudes to increase the happiness of adolescents. [ABSTRACT FROM AUTHOR]

Cytosine methylation alterations play key roles in gene regulation in plants interacting with biotrophic pathogens. For resistant and susceptible interactions of cucumber with the powdery mildew pathogen, Podosphaera xanthii , methylation of DNA cytosines were monitored by methylation-sensitive amplified polymorphism (MSAP) analysis from immediately prior to 96 h post inoculation (hpi). In both resistant and susceptible interactions, methylation levels significantly changed over time, but a significant association was observed for decreasing number of loci with demethylated CCGG motif in the susceptible cultivar compared to increasing numbers in the resistant cultivar. Sequencing of six demethylated MSAP fragments from the resistant cultivar and one from susceptible cultivar showed that all contained promoter and cis-acting regulatory elements (CAREs). For the resistant cultivar, three of these were in possible regulatory regions located within or near tRNA coding genes, and those three plus two others contained CAREs associated with response to biotic stress and defense hormones SA, MeJA, ABA and ET. One possible reason for demethylation in the resistant genomic tRNA genes may be that demethylation can de-suppress gene expression resulting in increasing the availability of certain amino acids for defense proteins. • Methyl-sensitive amplified polymorphism (MSAP) was used to study resistant and susceptible interaction of cucumber with Podosphaera xanthii. • In both resistant and susceptible interactions, methylation levels significantly changed over time post infection. • Number of demethylated loci were significantly lower than the susceptible cultivar. • Sequences of the MSAP fragments contained cis-acting regulatory elements mostly associated with response to biotic stress and defense hormones. [ABSTRACT FROM AUTHOR]

Detection of Toxoplasma gondii in meat products, which is responsible for severe disease in humans and in animals, is a great challenge. Recombinant antibodies (rAbs) have been offered as valuable tools for different diagnostic and therapeutic goals. In this study, a latex agglutination assessment for identification of Toxoplasma gondii in contaminated meat products was developed. For this propose, recombinant anti-P30 single-chain Fv (scFv) antibody gene was cloned into pET26b vector to express this antibody in high level. This gene's expression in Escherichia coli lead to production of significant amount of antibody (16 mg/L). After purification, the anti-P30 scFv was connected to beads of latex and used for agglutination test. These beads could agglutinate whole Toxoplasma gondii and contaminated meat samples. Thus, this rapid test may be applied to find contaminated samples. [ABSTRACT FROM AUTHOR]

Summary: In this paper, a fully coupled 2‐dimensional poroelastic displacement discontinuity method is used to investigate the refracturing process in horizontal wells. One of the objectives of refracturing is to access new reserves by adding new hydraulic fractures in zones that were bypassed in the initial fracturing attempt. Pore pressure depletion in the vicinity of old fractures directly affects the state of stress and eventually the propagation of newly created hydraulic fractures. Thus, a poroelastic analysis is required to identify guidelines for the refracturing process, in particular to understand the extension of the pore pressure depletion, and eventually, the orientation of new as well as old fractures. We propose a fully coupled approach to model the whole process of child fracture propagation in a depleted area between 2 parent fractures in the same wellbore. This approach omits the need of using multistep workflow that is regularly used to model the process. The maximum tensile stress criterion (σ criterion) is used for hydraulic fracture propagation. The proposed method is verified using available analytical solutions for total stress and pore pressure loading modes on a line fracture in drained and undrained conditions. Then, test cases of multifractured horizontal wells are studied to calculate the time evolution of the stress and pore pressure fields around old fractures and to understand the effect of these fields on the propagation path of newly created fractures. Finally, the effect of the pore pressure depletion on the propagation path of the newly created fractures in the bypassed area of the same wellbore is studied. The results show that the depleted areas around old fractures are highly affected by the extent and severity of the stress redistribution and pore pressure depletion. It is observed that a successful creation of new fractures may only happen in certain time frames. The results of this study provide new insights on the behavior of newly created fractures in depleted zones. They also clarify the relationship between stress change and pore pressure depletion in horizontal wells. [ABSTRACT FROM AUTHOR]

Groundwater is an important source of freshwater for domestic, agricultural and industrial uses in Iran. Groundwater quality assessment and environmental evaluation are considered as critical issues in recent years. Intensive human activities have resulted in significant changes in environment leading to serious groundwater contamination. This research proposes a two-part systematic approach to tackle heavy metals contamination problem in Rayen Basin (southeast Iran). The first part consists of determining geochemical characteristics and evaluating groundwater quality through application of water quality index and heavy metal pollution indices (i.e. HPI and MI). The second part includes ranking sampling stations based on heavy metals concentration in groundwater using linear assignment method. Six types of water could be identified according to the dominant cations and anions in samples: Ca-HCO3, Ca-SO4, Na-Cl, Na-HCO3, Na-SO4 and mixed water type. Calculation of indices revealed that natural and anthropogenic activities are playing a vital role in degrading groundwater quality in the study area. The proposed methodology can help in groundwater resource management and preventative activities by identifying risk factors and recognizing their pollution level. The results of this research provide useful and effective information for water pollution control and management and can be used in environmental studies in order to protect groundwater resources in the future. [ABSTRACT FROM AUTHOR]

Birds have been used intensively as biomonitors of halogenated flame retardants (HFRs), and several studies have reported elevated tissue concentrations and inter-individual variability for these contaminants. While diet is known to be an important exposure pathway for HFRs in birds, it has been suggested that exposure through air may represent an underestimated source of HFRs for certain species. However, a method was not available for measuring the atmospheric exposure of individual birds to HFRs or other semi-volatile contaminants. The goal of this study was to develop a bird-borne passive air sampler (PAS) enabling the determination of individual atmospheric exposure to gas- and particle-phase HFRs using the ring-billed gull (Larus delawarensis) nesting in the Montreal area (QC, Canada). The new miniaturized elliptical-shaped PAS (mean weight: 2.72 g) was tested using two sorbent types during three exposure periods (one, two and three weeks). Results showed that PAS using polyurethane foam (PUF) combined with a glass fiber filter collected all major polybrominated diphenyl ethers (PBDEs) and exhibited better performance for collecting highly hydrophobic DecaBDE mixture congeners compared to the PAS using polydimethylsiloxane (PDMS). Emerging HFRs including hexabromobenzene, Dechlorane 604 Component B, and Dechlorane plus (DP) isomers also were sampled by the PUF-based PAS. Sampling rates for most HFRs were comparable between the three exposure periods. This novel bird-borne PAS provides valuable information on the non-dietary exposure of free-ranging birds to HFRs. [ABSTRACT FROM AUTHOR]

This research focuses on the development of a fast ultrasonic assisted ferrofluid mediated methodology to obtain the optimum conditions for silver adsorption from aqueous solutions. For this purpose magnesium ferrite-copper sulfide chalcogenide was synthesized and employed as an efficient nanosorbent. The sorbent was characterized with energy-dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FE-SEM), X-ray powder diffraction (XRD) and vibrational sample magnetometry (VSM) techniques. For obtaining the optimal operating conditions of silver adsorption, response surface methodology (RSM) was used. Tests were performed by Box-Behnken design (BBD). The value of optimum conditions for silver adsorption include pH = 2.5, adsorbent dosage = 10.0 mg, sonicating time = 1 min and ionic strength = 2.2%. According optimum conditions, percentage of removal should be 99.34%. With replication of similar experiment (n = 6) average percentage of 100 ± 0.95% was obtained for Ag + adsorption which shows good agreement between predicted and experimental results. Silver ion adsorption follow Langmuir model with maximum sorption capacity of 2113 mg g −1 . Ultrasonic power helped to prepare ferrofluid and demonstrated that had an important role in better dispersing of it in solution and efficient adsorption of analyte. [ABSTRACT FROM AUTHOR]

Nanosheet gate-all-around transistor devices have been an important contenders for future technology nodes. Compared to FinFETs they have superior electrostatic control. The nanosheet architecture can also be vertically stacked thus achieving higher drive current on a same footprint area compared to a single nanowire or nanosheet. Accurate device simulations are crucial for the development and the optimization of the nanosheet transistors. With this in mind, we have developed and report a hierarchical simulations flow implemented in the Glasgow Nano-Electronic Simulation Software (NESS) in order to enable the accurate simulation and optimization of the nanosheet transistors. In this work we have carried out device simulations and showed that the more accurate NEGF simulations can be used for the calibration of the classical DD simulations within one single toolbox. Additionally we showed that the EME module can be used to extract the effective masses for confined structure like the nanosheet. • Nanosheet quantum mechanical simulations based on NEGF simulations. • Nanosheet drift–diffusion simulations and calibration against NEGF. • Hierarchical simulation flow implemented in NESS for the simulation of the nanosheet. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) have the capability of simultaneous sewage treatment and electricity generation. Modifying the cathode electrode enhances their efficiency. In this study, NiTiO 3 and CuNiTiO 3 were synthesized for practical application as cathode catalysts in a dual-chamber MFC and the performance of the modified cathodes was evaluated against a bare graphite electrode. SEM images showed that the particle sizes were mostly in the range of 40–120 and 20–80 nm for NiTiO 3 and CuNiTiO 3 , respectively. According to AFM results, CuNiTiO 3 presented a higher surface roughness than NiTiO 3. MFC using CuNiTiO 3 /G electrode with a reduction potential value of −0.27 V (vs. SCE) and a power density of 62.18 mW m−2 showed better oxygen reduction reaction (ORR) activity compared with NiTiO 3 /G and the bare graphite. MFC using CuNiTiO 3 cathode also showed the highest values in terms of chemical oxygen demand (COD) removal (75%) and the calculated coulombic efficiency (CE, 10%). The results obtained in this study, introduce CuNiTiO 3 as a promising electrocatalyst for further improvement of the cathodic reactions in MFC applications. • An efficient ORR catalyst based on NiTiO 3 with Cu-loaded nanoparticles was synthesized. • CuNiTiO 3 nanocomposite exhibited long-term stable voltage output in MFC experiment. • The high output voltage of 298.6 mV was obtained with CuNiTiO 3 /G cathode electrode in a dual-chamber MFC. • The CuNiTiO 3 /G cathode produced a power density of 62.12 mW m−2, higher than many previous studies. [ABSTRACT FROM AUTHOR]

Development of simple and economical sensors to measure the soil physical properties is of great importance in precision agriculture. Building on a previous study with a fusion of penetrometer, dielectric and high-frequency acoustic sensors, the present work was aimed to develop a combined penetrometer-dielectric-microphone-apparent electrical conductivity (EC a) sensor to present a cost-effective instrument for measuring the soil physical properties. The multi-sensor probe consists of a cone connected to a load cell, an integrated dielectric-EC a sensor and a microphone inside the cone to record the passive sound produced at the soil-cone interface. To evaluate the multi-sensor probe, soils with different textural compositions (clay content from 142 to 537 g kg-1) were remoulded at three levels of water content and three levels of bulk density. The probe was tested in vertical penetration tests using a hydraulic loading frame. The results of acoustic signal processing using principal component analysis showed satisfactory differentiation between coarse and fine-grained texture classes. The output of the dielectric sensor was related to soil volumetric water content with R2 = 0.81 with some texture dependency. With fusion of penetrometer, dielectric and microphone sensors, R2 increased to 0.9 with RMSE= 0.031 m3 m-3. The soil relative density was predicted from data fusion of penetrometer, dielectric and microphone sensors with a regression model with R2 = 0.86 and RMSE= 3.11%. The EC a sensor showed rational responses to the concentration of NaCl solution as well as decreased the RMSE of soil water content and relative density prediction when fused with the other sensors. The multi-sensor probe developed is an economical instrument for simultaneously measuring the soil physical properties. Field evaluations are needed to further evaluate the sensor in wider range of soil texture and soil characteristics as well as in on-the-go measurement to be applied in precision agriculture. [Display omitted] • Development of a combined penetrometer-dielectric-microphone-electrical conductivity. • Acoustic signals processing revealed useful information about soil texture, water content, & density. • Soil relative density was estimated from the combination of different sensors' output. • Sensors fusion improves the water content measurement accuracy in different soil textures. [ABSTRACT FROM AUTHOR]

• RTD quantum mechanical simulations based on the ballistic non-equilibrium Green's function (NEGF). • Role of random dopant fluctuations (RDFs) variability on the resonantpeak of resonant tunneling diodes (RTDs). • Application of RTDs for Physical Unclonable Functions (PUFs) generation and cryptographic purposes. In this paper, utilising the non-equilibrium Green's function (NEGF) formalism within the new device simulator NESS (Nano-Electronic Software Simulator) developed at the University of Glasgow's Device Modelling Group, we present quantum mechanical simulations of current flow in double-barrier III-V GaAs-AlGaAs nanowire resonant tunneling diodes (RTDs). NESS is a fast and modular Technology Computer Aided Design (TCAD) tool with flexible architecture which can take into account various sources of statistical variability in nanodevices. The aim of this work is to show that, in the RTD devices with nano-scale dimensions, there is a direct correlation between the position and the numbers of random dopants and the key device parameters, e.g., position of the resonant-peak (V R) variations as well as the shape and number of peaks in the output current–voltage (I-V) characteristics. Such V R variability can be used as a quantum fingerprint which can provide robust security and hence can be used to deliver Physical Unclonable Functions (PUFs). [ABSTRACT FROM AUTHOR]

In this paper, some tiling of sphere, ellipsoid, cylinder, and torus as the most abundant shapes of fullerenes, which contain at least one heptagon or octagon are investigated. We classify such tilings and derive some results on the number of their polygons. [ABSTRACT FROM PUBLISHER]

This quasi-experimental study reports on the effectiveness of three assessment strategies for students’ performance. The primary goal was to determine whether there are any improvements in students’ conceptual learning when a frequent (weekly) quiz is used for grading purposes compared to using midterm and final examinations only. Another goal was to ascertain whether students perform better when they are allowed to work collaboratively on quizzes compared to students taking quizzes individually. The results showed that when the quizzes are open-book, and students have a chance to collaborate (discuss in pairs how to answer the quiz questions), they perform significantly higher in their final examinations and their final projects (an indicator of conceptual learning). [ABSTRACT FROM AUTHOR]

In the last decades, several studies have been performed on polymers reinforced with steel cords or wires. However, the diameter of these steel reinforcements was still quite large (200 µm and more). Recently, stainless steel fibres were developed with a diameter down to 30 µm, which makes it possible to process steel fibre-reinforced composites in a similar way as carbon- or glass fibre-reinforced composites. If a proper combination of the ductile steel fibre and a ductile polymer is chosen, a ductile composite should be achieved. This article reports on the influence of the matrix toughness and the fibre/matrix adhesion strength on the ductility of the resulting steel fibre-reinforced textile composite. Tensile tests have been combined with microscopic analysis to investigate the relation between the mechanical behaviour and the observed damage morphology. It was found that distributed damage increases the toughness in a textile composite, because it softens the transversal structure that interlocks the ductile load-bearing yarns. This explains the counterintuitive observations regarding the influence of the matrix ductility and the fibre/matrix adhesion strength on the composite toughness. It was found that selecting a brittle epoxy matrix can lead to a ductile composite, because of the widely spread and dense cracking pattern that allows more strain on the ductile steel fibres. If the fibre–matrix adhesion is enhanced by introducing a silane coupling agent to the fibre surface, transversal cracks are prevented and the ductility of the composite drops drastically. These results for the textile composites are contrary to earlier findings on the UD and cross-ply counterparts. [ABSTRACT FROM AUTHOR]

Nucleus independent chemical shift (NICS) criterion was used to gauge the amount of aromaticity in a lot of publications in two last decades. Non-planar molecules with many polygons in different sheets that make angle together have not been studied by this criterion. Perhaps, one ascribes this deficiency to NICS index, but we think it is concern to depauperation in evaluation methods. Therefore, in this work, we try to evaluate aromaticity of two fullerene substructures bowl-shaped molecules, namely corannulene and sumanene as typical non-planar molecules by using of the NICS zz -scan method. The gauge-independent atomic orbital (GIAO) NMR calculations were done at B3LYP/6-311 + G(d) level of theory. Energetic criterion as another tool for evaluation of the aromaticity of compounds was used and discussed. Results shows that pentagon and hexagon rings in corannulene have antiaromatic and aromatic character, respectively and in sumanene, pentagon and outer hexagon rings have antiaromatic and aromatic character, respectively. However, the picture obtained based on the NICS computations did not provide any insight towards the real nature of current density in the corannulene and sumanene. [ABSTRACT FROM AUTHOR]

Background: Skin wound healing is very significant physiological procedure. It is quite obvious that promoting this healing is important too. One of the most popular compounds used ever for skin care is Vaccinium arctostaphylos essential oil. In this study we tried to compare the effects of V. arctostaphylos and zinc oxide on secondary intentioned openwound healing in rats Materials and Methods: In this experimental study, 75 male rats included in 5 groups: eucerin, zinc oxide, Vaccinium extract 10 and 20%, not treated. The whole operation was taking place under general anesthesia circumstances. Took photos continuously 21 days after wound creation and catch biopsy intervals were 3, 7, 14 and 21 days. Wounds areas are measured by Scion Image™ software. At last, all data were analyzed using SPSS-17. Results: As a result V. arctostaphylos with dose of 20% has significant healing properties compared to zinc oxide. These data were validating under confidence surface of 99% (p<0.01). Conclusion: Base on earned data it will be suitable to use of zinc oxide ointment for healing reason but there is opportunity to researcher to survey higher dose of this plant extraction in contrast of zinc oxide. [ABSTRACT FROM AUTHOR]

Highlights: [•] Use of Stated Preference techniques for analysing pedestrian preferences towards safety in roundabouts (approach that has not been used so far). [•] Use of VISSIM traffic micro-simulations to successfully include difficult-to-communicate attributes in Stated Preference web survey. [•] Quantification of the importance of different design and operational features to increase pedestrian safety perception in roundabouts. [•] Quantification of how some negative features of roundabouts can be compensated for by design features. [•] Aid to decision and policy making process related to roundabouts in the region. [ABSTRACT FROM AUTHOR]

Background: Nardostachys and hypericum due to the effects of sedation, anticonvulsant, analgesic and anti-depressants has especial place in traditional medicine. Principal component and the alkaloid extract of valerian and isovalerate, valeric acid and the extract of hypericum is hypersin and hyperforin. Materials and Methods: We conducted this study, valerian rhizome by chloroform: methanol (70:30) was extracted in order to obtain total extract produced the N-hexane and studied chemically have been took by Gc-Ms. Hydro-alcoholic extract of aerial valerian tea was prepared for study. In order to study the comparative effects of soothing extracts of valerian and hypericum in different groups of female rat extract of valerian with doses of 100 mg/kg, 200 mg/kg, 400 mg/kg, and extracts of hypericum with a dose of 250 mg/kg, 500 mg/kg and DMSO (control) with the same volume of 15 minutes prior to the assessment of sedative and sleep (sleep duration induced with ketamine dose and 40 mg/kg were injected intraperitoneally). Results: The results indicate a significant increase in sleep time induced by ketamine in the treatment groups with high and low doses of valerian extracts and the hypericum is significant at the 0.01 level. Conclusion: The results show that the extract of valerian in the dose of 200 mg/kg in compress of dose of hypericum 500 mg/kg contains the significant anesthetic effects. [ABSTRACT FROM AUTHOR]

Abstract: This article employs an adaptive wear modeling method to study the wear progress in radial sliding bearings contacting with a rotary shaft. Mixed Lagrangian–Eulerian formulation has been used to simulate the contact condition between the bearing and the shaft, and the local wear evolution is modeled using the Archard equation. In the developed wear processor algorithm, not only remeshing is performed on the contact elements, but also is executed for their proximity elements. In this way the wear simulation becomes independent of the size of the contact elements. Validation was done for a laminated polymeric composite bearing. The composite has been modeled as a linear orthotropic material. The wear coefficients were obtained from flat-on-flat experiments and were applied as pressure and velocity dependent parameters in the wear processor. Finally, the effect of the clearance on the wear of the radial bearings has been studied numerically. The simulations also demonstrate how the contact pressure evolves during the wear process, and how the clearance influences this evolution. [Copyright &y& Elsevier]

Both pilocytic astrocytoma (PA) and hemangioblastoma (HB) are common primary neoplasms of the posterior fossa with similar radiological manifestations. This study was conducted to evaluate the role of Radiomics in differentiating these two conditions in adults. After a retrospective search of our institutional imaging archive, adult patients with a known diagnosis of PA or HB were included. We reviewed each patient's most recent preoperative brain magnetic resonance imaging (MRI). The solid enhancing nodule of each lesion on post-contrast T1 sequence was manually segmented. Multiple Radiomics features were then extracted from each nodule using the Pyradiomics library. Subsequently, the most predictive features were identified by feature selection models. Following this, different machine learning (ML) models were constructed based on these selected features to classify lesions as PA or HB. Finally, we evaluated the performance of each model by leave-one-out cross-validation. With inclusion and exclusion criteria, 34 enhancing PA nodules and 39 HB nodules were selected. A total of 115 features were extracted from each enhancing nodule. Twelve characteristics were detected as most predictive of histopathological diagnosis. Among various ML models, the neural network had the best performance in differentiating these two conditions with an AUC of 0.9 and an accuracy of 82%. In this retrospective study, Radiomics MRI techniques demonstrated high performance in distinguishing adult posterior fossa PA from HB. Future development of Radiomics models may advance presurgical diagnosis of these two conditions when added to routine clinical practice and thus improve patient management. • Differentiation between hemangioblastoma and pilocytic Astrocytoma in the "adult" is challenging on conventional medical imaging. • However, an accurate preoperative diagnosis is crucial and can significantly alter patient management and surgical technique. • Our preliminary results regarding the application of Radiomics appear promising for this task, and we got an AUC of 0.9 without using any clinical information such as the patient's age. [ABSTRACT FROM AUTHOR]

PURPOSE: To compare arterial blood gas analysis of patients who underwent percutaneous nephrolithotomy (PCNL) in flank position under ultrasonography guidance with PCNL in prone and supine positions under fluoroscopic guidance. MATERIALS AND METHODS: In a clinical trial, a total of 90 patients with no upper urinary tract abnormalities were candidate for the PCNL. They were assigned into three groups using pseudorandomization method (30 patients in each group). Patients in group 1 underwent ultrasonography-guided PCNL in flank position. Patients in groups 2 and 3 underwent fluoroscopic-guided PCNL in prone and supine positions, respectively. Arterial blood gas was taken just before and 20 minutes after repositioning. RESULTS: The patients' mean age was 40.8 ± 6.9, 39.4 ± 10.6, and 37.2 ± 11.1 years in flank, prone, and supine positions, respectively (P = .69). The mean body mass index was 27.8 ± 3.4, 26.7 ± 4.7, and 28.1 ± 5.1 kg/m² in flank, prone, and supine positions, respectively (P = .21). Arterial oxygen pressure (PaO) increased significantly in flank (111.7 ± 43.8 to 132.8 ± 58.1 mmHg; P = .01) and prone (118.6 ± 50.2 to 134.6 ± 58.5 mmHg; P < .001) positions and decreased nonsignificantly in supine group (121.7 ± 64.5 to 119.7 ± 60.9 mmHg; P = .23). With surgical positioning, there were no significant changes demonstrated in PaCO and serum concentration of HCO in the flank, prone, and supine groups. CONCLUSION: We could suggest that flank and prone positions could improve patients' oxygenation during PCNL procedure. [ABSTRACT FROM AUTHOR]

Official statistics from several resources in Iran indicate that female enrollment and achievement in Iranian universities has recently exceeded that of male students. Despite the fact that a religious government has been ruling the country for three decades, and despite many regulations against women, Iranian women have managed to overcome social, cultural, and political barriers. They have also been able to pass a highly competitive entry exam to enter the university at higher performance rates than male students. In this study it was proposed that this increasing enrollment and graduation rate might be attributed to their gender-based self-confidence and their self-efficacy. The results showed that female students scored higher on collective, gender-based self-confidence but their personal feeling about their gender was more negative and their general self-efficacy was not different from the self-efficacy of male students. [ABSTRACT FROM PUBLISHER]

Abstract: The Implicit Association Test (IAT) was developed in response to reports of low validity of explicit (self-report) measures of attitudes, stereotypes, and prejudices. Usually, people are unwilling to report what they think and feel about other races, groups, and nationalities. The IAT has been written about in many books, newspapers, journal articles, websites, and has been featured frequently on radio and television many times; its web site has now reached a peak of 5 million visits. However, despite this popularity its validity and particularly its reliability is under question. This article reports on the validity and reliability of the IAT. Four different experiments were conducted on 150 students at California State University, Long Beach to investigate the temporal reliability of IAT. Also students’ opinion (trust) about the validity and reliability of the test was evaluated. The results showed that while there are numerous reports of moderate validity of the test, its reliability as measured in this study, particularly for the first time users, is relatively low. Familiarity with similar tests, however, improves its reliability. [Copyright &y& Elsevier]

In this study, we develop a finite element model to examine the oblique soccer ball bounce. A careful simulation of the interaction between the ball membrane and air pressure in the ball makes the model more realistic than analytical models, and helps us to conduct an accurate study on the effect of different parameters on a bouncing ball. This finite element model includes a surface-based fluid cavity to model the mechanical response between the ball carcass and the internal air of the ball. An experimental set-up was devised to study the bounce of the ball in game-relevant impact conditions. Ball speed, angle, and spin were measured before and after the bounce, as well as ball deformation and the forces during the impact. The finite element model has been validated with three different sets of data, and the results demonstrate that the finite element model reported here is a valuable tool for the study of ball bounce. After validation of the model, the effect of the friction coefficient on soccer ball bounce was studied numerically. Simulation results show that increasing the friction coefficient may result in reversal of the horizontal impact force. [ABSTRACT FROM AUTHOR]

Abstract: This paper includes the experimental and numerical study of the mechanical behavior of a large scale composite journal bearing, used in marine applications. The bearing is a phenolic based composite with PTFE filler, and is strengthened by polyester fibers. The experiments have been done with a test apparatus which is designed to evaluate the tribological behavior of large-scale composite journal bearings under the oscillating rotation of the shaft. The simulation part of the study mainly focuses on the three-dimensional quasi-static model in which mixed Eulerian–Lagrangian formulation is used to simulate the rotation of the shaft and the contact between the composite bearing and the shaft. Moreover, in order to qualify the quasi-static model, a simplified two-dimensional dynamic model is developed. The experimental and simulation results are in a good agreement and indicate that the quasi-static mixed Eulerian–Lagrangian model is an appropriate method to simulate the sliding contact between the composite journal bearing and oscillating shaft. Further the results show that due to the generation of high hoop stresses in the bearing by the freeze fitting process, this method can extremely decrease the loading capacity of the laminated composite journal bearings compared to adhesive bonding method. [Copyright &y& Elsevier]

Abstract: This experimental project investigated the reliability and validity of rubrics in assessment of students’ written responses to a social science “writing prompt”. The participants were asked to grade one of the two samples of writing assuming it was written by a graduate student. In fact both samples were prepared by the authors. The first sample was well written in terms of sentence structure, spelling, grammar, and punctuation; however, the author did not fully answer the question. The second sample fully answered each part of the question, but included multiple errors in structure, spelling, grammar and punctuation. In the first experiment, the first sample was assessed by participants once without a rubric and once with a rubric. In the second experiment, the second sample was assessed by participants once without a rubric and once with a rubric. The results showed that raters were significantly influenced by mechanical characteristics of students’ writing rather than the content even when they used a rubric. Study results also indicated that using rubrics may not improve the reliability or validity of assessment if raters are not well trained on how to design and employ them effectively. [Copyright &y& Elsevier]

Microstructural defects and mechanical anisotropy are regarded as the main obstacles in additively manufactured, laser powder bed fusion (LPBF) IN718 superalloy, decelerating industrial development of the related components. Hot isostatic pressing (HIP) is an effective solution to overcome these challenges. In this study, standard heat treatment (HT) with and without prior HIPing was applied to the LPBF IN718 and the impacts of the HIP operation on microstructures and room- and high-temperature mechanical anisotropy were studied. Observations showed that intrinsic pores and large contour defects were significantly closed by HIPing and consequently the relative density enhanced from 99.50% to 99.96%. The highly distorted columnar structure of the HT specimen was broken down due to recrystallization, and an equiaxed morphology with about 5-time coarser grain size appeared in the HIP + HT specimens. Although too many transgranular precipitates were observed in the HT microstructure, they were just formed at grain boundaries when HIP was carried out before HT. Furthermore, the formation of nano-scale γʺ/γʹ/γʺ co-precipitates was favored by HIPing which had a positive effect on strengthening. It was also found that prior HIPing effectively mitigated mechanical anisotropy both at room- and high-temperatures by influencing several factors. The degree of room-temperature mechanical anisotropy was reduced from 11.6% (HT) to 3.5% (HIP + HT) by HIPing and mitigated from 4% to 2% at 650 °C. While the fracture mechanism was orientation-dependent in the HT samples, it was completely ductile for the HIP + HT samples in all circumstances. • Relative density of AM IN718 superalloy enhanced from 99.50% to 99.96% by HIPing. • Nano-scale γʹ/γʺ composite precipitates formed in the HIPed alloy. • Residual stress is the driving force for recrystallization in the AM components. • Mechanical anisotropy reduced by HIPing at both room- and high-temperatures. [ABSTRACT FROM AUTHOR]

The most frequently used computerized measure of cognitive styles is Riding''s Cognitive Styles Analysis (CSA). Although CSA is not well known in North American institutions, it is quite popular among European universities and organizations. Unlike many other measures of cognitive style inventories, CSA has been under substantial empirical investigation. After investigating several cognitive style inventories the authors found the structure and the theoretical support of (CSA) to be more powerful than that of others. However, no empirical research has been conducted on the reliability of CSA. In this project three different experiments were conducted with three different samples to investigate the reliability of CSA. In all three experiments the reliability was shown to be low. Considering the profound theoretical background of CSA, and also regarding the difference in the reliability of the two dimensions of the test, some suggestions are presented in this paper to improve the validity and reliability of CSA. The authors expect that these comments and suggestions would be useful not only for improving CSA, but also for designing any other cognitive or learning style test. [Copyright &y& Elsevier]

The occurrence of the Islamic revolution in Iran in 1979, followed by a large-scale “Islamization” of society, resulted in some unique developments with regard to religious life in this country. Over the past two decades, there has been a lively debate among social scientists about the nature of such developments, and over their implications for other Middle Eastern and Islamic societies. Most of the contributions to this debate so far have been limited to the examination of different theoretical possibilities, without strong references to empirical evidence. In the present study, we attempt to address this shortcoming in the existing literature on religious developments in Iran by relying on a rich set of empirical data recently gathered through a large-scale national survey of values and attitudes in Iran. Through a composite index of religious sentiments, we explored the magnitude and the nature of religious sentiments among groups of different age and gender. Also, we examined changes with regard to religiosity in the period between 1975 and 2001. The outstanding finding is that the establishment of a theocratic regime in Iran has led to the transformation of the nature of faith, marked by a noticeable shift from “organized” to a more “personalized” religion, in which the emphasis is placed on beliefs rather than on practices. Also, among both beliefs and practices, more emphasis is placed on those with a purely individual nature, or with a social nature but organized through civic and nongovernmental bodies, as opposed to those commanded by the government. The article ends with a brief discussion of the implications of such developments for the existing debate among sociologists of religion on secularization and “de-secularization.” Our findings indicate that any linear perspective on the demise or survival of religion in society will unreasonably brush aside the fact that religion is not merely a social institution, but also a “cultural resource” that individuals may draw upon, depending on their surrounding sociopolitical circumstances and their reading of those circumstances. [ABSTRACT FROM AUTHOR]

Enrichment of ultrafine liberated valuable minerals from their associated gangue phases is one of the emerging investigation topics within mineral processing and recycling. Using green flotation reagents and turning processes into eco-friendly systems is also one of the challenges in the green transition of ore beneficiation plants. Starch and Tanin as biodegradable depressants for hematite depression have been commercially used in various iron ore processing plants. However, their depression effects on ultrafine particles were not systemically assessed and compared. To fill this gap, this investigation examined the effects of starch, tannin, their mixtures (different ratios), and their different conditioning sequence on the floatability of ultrafine quartz and hematite (− 15 µm). Since the macromolecular polymer of these biodegradable depressants can bind particles together and flocculate them, turbidity analyses were used to assess their optimum ratio for hematite depression without affecting quartz floatability. Turbidity analyses provided a mixture of tannin and starch might enhance the flotation separation of quartz from hematite. Starch could flocculate ultrafine hematite particles, while tannin could disperse ultrafine quartz particles. Floatability experiments indicated that starch had the highest performance in hematite depression (lowest effect on quartz particles) compared to other conditions. Surface analyses (zeta potential and FTIR) proved floatability outcomes and highlighted starch had stronger adsorption on the hematite surface than tannin. [ABSTRACT FROM AUTHOR]

The nature of melting and solidification phenomena during selective laser melting (SLM) process leads to a strong crystallographic texture in the as-built SLM components which causes mechanical anisotropy. This anisotropy is usually reduced by either optimization of the laser scanning strategy during the SLM process or high-temperature heat treatment. Microstructure and mechanical anisotropy of SLMed Inconel 718 (IN718) superalloy were investigated in this study by means of XRD, SEM, EBSD and small punch testing (SPT) method at room and high temperatures. The SPT data were validated against uniaxial tensile testing and corresponding equations were proposed to determine yield and ultimate tensile strengths of the fabricated parts. Significant differences in mechanical behavior of the side and top views were mainly achieved due to the contribution of (100) columnar grains texture. It was found that the IN718 SLM parts possess 54% greater maximum force in the side view compared to the top one at room temperature. However, the side view maximum force lowered about 37% at 650 °C, while no significant decrease was observed for the top view sample. Fractography of small punched specimens showed ductile fracture surface for the side view compared to transgranular brittle surface for the top view at room temperature. Both views exhibited more brittle fracture at elevated temperature with different fracture surface morphologies, intergranular in the side view and cleavage along with Laves phases in the top view. The present work clearly demonstrates that SPT can successfully predict mechanical anisotropy in the as-built SLM IN718 superalloy. • The (100) 〈001〉 cubic texture component is formed in the SLMed IN718 superalloy. • The side view exhibited 35% greater maximum load at RT. • SPT was found to be suitable for predicting the level of anisotropy in the SLMed IN718. • Side view fracture mode was ductile, while top view one brittle fracture at RT. • Side view fractured intergranularly, while top view transgranularly at 650 °C. [ABSTRACT FROM AUTHOR]

In this study, a fast multipole method (FMM) is used to decrease the computational time of a fully-coupled poroelastic hydraulic fracture model with a controllable effect on its accuracy. The hydraulic fracture model is based on the fully-coupled poroelastic formulation of the displacement discontinuity method (DDM) which is a special formulation of the boundary element method (BEM). DDM is a powerful and efficient method for problems involving fractures. However, this method involves the multiplication of a dense matrix with a vector in several places. Thus, the DMM algorithm slows down drastically as the number of elements increases, and even more so with the inclusion of necessary details such as poroelasticity, which makes the solution history-dependent. Rather, FMM is a technique to expedite matrix-vector multiplications, within a controllable error range, by approximating the far-range interactions without forming the matrix explicitly. In doing so, FMM offers a leverage in the computational efficiency by modifying the algorithm of the fully-coupled poroelastic displacement discontinuity method (PDMM) in two places. The first modification is in the time-marching scheme, which accounts for the solution of previous time steps to compute the current time step. The second modification is in the generalized minimal residual method (GMRES), where the unknowns are solved for iteratively. Several examples are provided to show the efficiency of the proposed fast multipole fully-coupled poroelastic displacement discontinuity model (FMPDDM) in problems with large degrees of freedom (in time and space). These examples include hydraulic fracturing of a horizontal well and randomly distributed pressurized fractures at different orientations with respect to principal horizontal stresses. The results of FMPDDM are compared to PDDM in terms of computational time and accuracy, which demonstrates that FMPDDM decreases the computation time by up to a factor of 70 for a case with 20000 piece-wise constant elements and a single time step. The difference between the computational times of FMPDDM and PDDM can be higher for a larger number of elements and time steps. Moreover, the associated absolute value of relative error for a problem of this size is observed to be less than 4% for the hydraulic fracture example, and less than 0.5% for the example of randomly distributed pressurized fractures. Furthermore, the solution of tip displacements using both methods are used to compare the computation of stress intensity factors (SIF) in mode I and II, which are needed for fracture propagation. The calculated displacement discontinuities reveal that the SIF calculation using FMPDDM has a negligible error compared to PDDM. Therefore, FMPDDM will not affect the estimation of the fracture propagation direction. Accordingly, the proposed algorithm may be used for fracture propagation studies to substantially reduce the computational time. [ABSTRACT FROM AUTHOR]