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In the conventional multilevel inverters, occurrence of a fault in one or more power switches can cause abnormal changes in the output waveforms. Besides, increasing the applied power switches results to an increase in the possibility of fault on the power switches. Accordingly, providing a comprehensive structure with high fault-tolerant capability is one of the vital requirements and critical challenges. To tackle these issues, this study first presents and explores a new basic unit and staircase module (SM) and then extends and optimizes it to yield a reconfigurable multi-level inverter (MLI) with more levels and different goals. The proposed MLI can continue to operate when open-circuit faults in switches. This advantage of the proposed structure is achieved without any redundant legs or switches. For further investigation, a comparison is made in terms of the number of power switches, drivers, dc sources, and reliability between the proposed and similar structures. To control the output voltage levels, the strategy of fundamental frequency switching triggers the configured topology. The carrier signals are reconfigured under fault conditions based on levels to be generated by bypassing the faulted switch. The validity of the established MLI with its fault-tolerant capability is certified through both computer simulations using the MATLAB/Simulink platform and laboratory prototype implementations. • An efficient base structure for MLI inverters is proposed. • A basic structure development strategy is developed to achieve an increased number of voltage levels. • The losses and total blocked voltage on the switches are checked. • The fault tolerance of the structure against the open circuit fault of switches is investigated. • The reliability of the proposed structure is calculated and compared with similar structures. [ABSTRACT FROM AUTHOR]

The extraction and processing of iron ore produce significant amounts of mine tailings, causing environmental problems that require storage in reservoirs or dams. Using these materials in construction helps minimize their adverse impacts. This study analyzed the geotechnical properties of Magnetite and Hematite iron ore tailings (MIOT, HIOT) from the Golgohar mine in Sirjan, Iran. Two IOTs were compacted using the Standard Proctor technique after being treated with 5, 7, and 9 % Portland cement. Following curing time, treated samples were tested at different stress levels for resilient modulus. Based on the results, to meet strength and durability requirements, cement-treated MIOT needs 9 % cement. Contrastingly, only 5 % of the cement for cement-treated HIOT met the criterion. The resilient moduli of untreated MIOT and HIOT materials heavily rely on the confining pressure, resulting in a minimal decrease in modulus by increasing deviatoric stress. The effect of cement on resilient modulus is more pronounced in high confining stresses than in low confining stresses in MIOT and HIOT materials. A comparison of different non-linear models showed that 'Universal' model is the best fit for laboratory results of cement-treated MIOT and HIOT materials, as it accounts for hardening and softening behavior. • Physical and geotechnical characteristics of magnetite and hematite iron ore tailings were explored. • UCS, Durability, and resilient modulus of untreated and cement-treated iron ore tailing were measured. • Effect of compaction moisture, curing time and cement content on the USC was investigated. • Effect of stress state, curing time and cement content on the resilient modulus was investigated. • Different non-linear models were assessed for resilient behavior of treated and cement-treated iron ore tailings. [ABSTRACT FROM AUTHOR]

• MEI enhances HOTS and academic achievement in university students. • EEG analysis showed brain activity changes with MEI. • Alpha to beta ratio decreased post-meditation, showing increased attentiveness. The current study examined the role of mindfulness-enhancing instruction (MEI) in university students' Electroencephalogram (EEG) dynamics, Higher Order Thinking Skills (HOTS), and effective learning. In so doing, 60 junior university students, being screened out of 72 available sample, were randomly assigned into two groups. MEI was incorporated into class activities of the experimental group during the term. A package containing a host of activities was devised, integrating general meditation practices with educational MEI. These in-class activities were complemented with daily at-home practices offered by a mobile application. To assess participants' level of HOTS, two tests from the "Watson-Glaser Critical Thinking Appraisal" (CTA) (Form A) was utilized. In this study, inference and deduction modules were included. The participants responded to the tests while they were involved in EEG acquisition. The results of statistical analysis demonstrated the efficiency of the implemented MEI in enhancing two dimensions of HOTS (inference-making & deduction) as well as academic achievement. The EEG analysis demonstrated notable changes in the experimental group's brain activity patterns. Specifically, there was a significant decrease in the ratio of energy in the alpha to beta frequency band (α/β ratio) for Fp1 and Fp2 channels post-meditation, indicative of heightened attentiveness. Conversely, the control group exhibited less pronounced changes in the EEG measures. [ABSTRACT FROM AUTHOR]

[Display omitted] Exosomes are naturally derived information carriers that present interest as drug delivery systems. However, their vague cargo and isolation difficulties hinder their use in clinical practice. To overcome these limitations, we developed exosome-like nanoparticles, consisted of the main lipids of exosomes, using two distinct methods: thin-film hydration and 3D-printed microfluidics. Our novel microfluidic device, fabricated through digital light processing printing, demonstrated a favorable architecture to produce exosome-like nanoparticles. We compared these two techniques by analyzing the physicochemical characteristics (size, size distribution, and ζ-potential) of both unloaded and genistein-loaded exosome-like nanoparticles, using dynamic and electrophoretic light scattering. Our findings revealed that the presence of small lipophilic molecules, cholesterol and/or genistein, influenced the characteristics of the final formulations differently based on the development approach. Regardless of the initial differences of the formulations, all exosome-like nanoparticles, whether loaded with genistein or not, exhibited remarkable colloidal stability over time. Furthermore, an encapsulation efficiency of over 87% for genistein was achieved in all cases. Additionally, thermal analysis uncovered the presence of metastable phases within the membranes, which could impact the drug delivery efficiency. In summary, this study provides a comprehensive comparison between conventional and innovative methods for producing complex liposomal nanosystems, exemplified by exosome-like nanoparticles. [ABSTRACT FROM AUTHOR]

• Fractures in low-permeability reservoir dominates the hydrocarbon transport. • Produced lean gas is successfully applied in the cyclic solvent injection process. • The fracture properties control the cyclic solvent injection performance therein. • The induced fractures result in an enhanced oil recovery by 18.5% in the research. Recovery factors associated with primary recovery (pressure depletion) schemes are often small (<5–10%) for low-permeability hydrocarbon reservoirs. As a result, cyclic solvent injection (CSI) schemes, using CO 2 and produced gas, are currently being considered for enhanced hydrocarbon recovery (EOR). Fracture networks, generated during hydraulic fracturing stimulation, affect both primary and enhanced recovery by increasing the surface area contacted with the low-permeability reservoir matrix. However, experimental studies of the impact of induced (hydraulic) fractures on CSI performance are sparse, particularly those that provide a realistic representation of the fracturing process by inducing fractures under stress to better represent fracture conditions (e.g., fracture surface area, fracture surface roughness). Therefore, the primary objective of this work is to develop a laboratory-based workflow for evaluating the effectiveness of fracture system in tight oil reservoirs to enhance the oil recovery during a typical CSI cycle using a combination of core-scale techniques. An in-house core-flooding methodology, that combines 'in situ' fracturing and cyclic gas injection, was applied. The experimental procedure includes: 1) performing multiple cycles of lean gas (i.e., 80% C 1 + 20% C 2) injection into an oil-saturated 'intact' core plug until maximum oil recovery (5%) is reached, 2) artificially fracturing the core plug under stress, 3) repeating multiple cycles of lean gas injection into the artificially-fractured core plug, under similar experimental conditions as those used for the intact core, until maximum oil recovery (23%) is reached, and 4) measuring the fractured-core liquid permeability. A well-characterized tight siltstone core plug sample obtained from the Canadian Montney Formation was analyzed as an example. The experimental results indicate that 1) fracturing under stress results in an increase in surface area and permeability, and 2) the recovery factor is enhanced by ∼ 18% after fracturing (e.g., from ∼ 5% for intact core plug to ∼ 23% for artificially-fractured core plug). This study provides a proof-of-concept experimental approach for evaluating the impact of induced fractures on CSI recovery using an identical core plug sample (intact and fractured). The proposed experimental methodology could serve as a workflow for laboratory-scale evaluation of the impact of induced fractures on CSI performance in tight hydrocarbon reservoirs. [ABSTRACT FROM AUTHOR]

Chenopodium album is a troublesome arable weed species which has evolved resistance to dicamba in New Zealand. The objective of this work was to investigate the patterns of absorption, translocation and metabolism of dicamba in resistant and susceptible C. album populations. No significant differences in absorption by the two populations were measured, with over 80% of applied herbicide entering the plants of both populations during the 5 days after application. The 14 C from dicamba was also readily translocated out of the treated leaf, with this occurring more rapidly in resistant plants than susceptible plants. The majority of the 14 C from dicamba was translocated into untreated leaves in both populations. However, by 5 days after application, 18.4% of the absorbed 14 C from dicamba was found in stem material for susceptible plants, compared with only 5.1% for resistant plants. No dicamba metabolism was detected for either population. Based on the results of this study, the mechanism of resistance to dicamba in C. album could not be adequately explained by differential patterns of absorption, translocation or metabolism, but the mechanism appears to differ from previously published cases of dicamba resistance. [ABSTRACT FROM AUTHOR]

• Modeling of a series of successive credible outages causing the LE using fault chain theory; • Introducing a novel prediction index to determine the next successive line outages; • Proposing a vulnerability index to identify the critical relays; • Presenting an optimal control strategy to restore the acceptable relay margin. One of the main factors in triggering cascading outages is the undesired operation of zone-3 vulnerable distance relays under static load encroachment. In this paper, to avoid the contribution of vulnerable relays in cascading outages, a novel online vulnerability assessment method based on fault chain theory is proposed to identify the critical relays. The main idea is to use the fault chain theory to model the process of valid successive line outages that occur step by step and lead to load encroachment into zone-3 distance relay. A novel normalized prediction index based on relay margin change, margin sensitivity variation, load encroachment factor and overload tolerance of the line is proposed to predict the next possible outage. The distance relays involved in most fault chains are identified as vulnerable relays requiring to be controlled. A suitable index is presented to detect the critical relays. In this regard, an optimal control strategy is also proposed to restore the acceptable operating margins of the identified vulnerable zone-3 distance relays in the system's emergency condition. The validity of the proposed approach is evaluated on New England 39 bus system to confirm the effectiveness and benefits of the proposed method. The obtained results are exciting. [ABSTRACT FROM AUTHOR]

Wiper applicators allow herbicides to be directly transferred onto the surface of target plants, thereby avoiding application to nearby desirable plants of shorter stature. This form of herbicide application can greatly reduce costs of weed control and risks of environmental contamination. The risk of drift to susceptible plants in areas adjacent to the weed control operations can also be eliminated by using wiper applicators. Despite the huge potential for using wiper applicators to improve weed control in agricultural and non-agricultural sectors, there has been only limited research into the factors that might affect the performance and efficacy of wiper applicators. These factors include the growth stage of weeds at the time of application, types of herbicide used, design of wiper applicator and the quantity of herbicide deposited on plants. In this review, gaps in knowledge about wiper applicators are discussed and priorities for future research are suggested. [ABSTRACT FROM AUTHOR]

This study examines the effect of yoga training program (YTP) on the severity of autism in children with High Function Autism (HFA). Twenty-nine children aged 7 to 15 (mean = 11.22, SD = 2.91) years were randomly allocated to either yoga or control group. The participants in the yoga group received an 8-week (24-session) Yoga Training Program (YTP). Parents or caregivers of participants completed autism treatment evaluation checklist (ATEC) at baseline and the end of the intervention. The results of the analysis showed that there were significant differences between the two groups with regards to all ATEC sub-scores except ATEC I (speech/language/communication). This study provides support for the implementation of a yoga training program and identifies specific procedural enhancements to reduce the severity of symptoms in children with autism. [ABSTRACT FROM AUTHOR]