Using shock generator for the fuel mixing of the extruded single 4-lobe nozzle at supersonic combustion chamber.

The importance of the fuel injection configuration on the propulsion efficiency of high-speed vehicles is apparent. In this article, the use of an annular extruded 4-lobe nozzle for the injection of fuel jet in a supersonic combustor of a scramjet engine in the existence of a shock generator is examined. The main aim of this study is to obtain the efficient jet arrangement for efficient fuel mixing inside the engine of hypersonic vehicles. A numerical approach is used to model the supersonic air stream and cross-jet flow with the SST turbulence model. The role of nozzle altitude and internal air jet on the fuel mixing of the hydrogen within the high-speed domain are disclosed. The importance of the horseshoe vortex and counter-rotating vortex on the fuel distribution is also presented. Our results show that the usage of a coaxial jet instead of an annular jet would increase fuel mixing by more than 40% in the combustion chamber.

Comparison activity of pure and chromium-doped nickel oxide nanoparticles for the selective removal of dyes from water.

The current study involves a synthesis of a composite of nickel oxide nanoparticles (NiONPs) with a chromium dopant to yield (Cr/NiONPs). Synthesis of nickel oxide was performed by the co-precipitation method. The synthesis of the composite was conducted by the impregnation method. FTIR, EDX, SEM, and XRD were used to characterize the synthesized materials. The synthesised materials' point zero charges (PZC) were performed using the potentiometric titration method. The obtained results show that the PZC for neat nickel oxide was around 5, and it was around 8 for Cr/NiONPs. The adsorption action of the prepared materials was examined by applying them to remove Reactive Red 2 (RR2) and Crystal Violate (CV) dyes from solutions. The outcomes demonstrated that Cr/NiONPs were stronger in the removal of dyes than NiONPs. Cr/NiONPs achieved 99.9% removal of dyes after 1 h. Adsorption isotherms involving Freundlich and Langmuir adsorption isotherms were also conducted, and the outcomes indicated that the most accurate representation of the adsorption data was offered by Langmuir adsorption isotherms. Additionally, it was discovered that the adsorption characteristics of the NiONPs and Cr/NiONPs correspond well with the pseudo-second-order kinetic model. Each of the NiONPs and Cr/NiONPs was reused five times, and the results display that the effectiveness of the removal of RR2 dye slightly declined with the increase in reuse cycles; it lost only 5% of its original efficiency after the 5 cycles. Generally, Cr/NiONPs showed better reusability than NiONPs under the same conditions.

High-performance photocatalytic degradation and antifungal activity of chromium-doped nickel oxide nanoparticles.

The elimination of pollutants such as dyes and fungi has become a tedious process hence there is a need for multifunctional materials that can be used for the removal or degradation of various pollutants from wastewater. Here, a nickel oxide nanoparticle (NiONPs) was synthesized by the co-precipitation method. In the current study, a composite of nickel oxide nanoparticles (NiONPs) was synthesized using nitrogen and chromium as dopants to create (N/NiONPs) and (Cr/N/NiONPs), respectively and used for the removal of dyes and fungi. The synthesized nanocomposites were characterized using zeta potential (ZP), scanning electron microscopy (SEM), X-rays diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The NiONPs, N/NiONPs and Cr/N/NiONPs were tested for the degradation of two dye pollutants, Reactive blue 13 (RB13) and eosin dye. The obtained results showed that Cr/N/NiONPs were more efficient than NiONPs and N/NiONPs for dye degradation by applying the same irradiation conditions. The Cr/N/NiONPs nanocomposites showed very good degradation efficiency of dye up to 94.2% for the RB13 and 90.8% for the eosin. We also examined the antifungal action of the NiONPs, N/NiONPs and Cr/N/NiONPs against Trichoderma fungus. The results showed that the Cr/N/NiONPs have an extremely strong antifungal impact on Trichoderma. This could be explained by the strong adhesion of Cr/N/NiONPs to the Trichoderma surface due to electrostatic attraction. This work has demonstrated that it is possible to create environmentally safe materials that can be used for the degradation of different dyes and the improvement of more effective antifungal treatments with lower active agent doses for fungus control with potential big economic benefits.

Towards a promising systematic approach to the synthesis of CZTS solar cells.

This study aims to enhance the CZTS device's overall efficiency, the key research area has been identified in this study is to explore the effects of a novel, low-cost, and simplified, deposition method to improve the optoelectronic properties of the buffer layer in the fabrication of CZTS thin film solar cells. Herein, an effective way of addressing this challenge is through adjusting the absorbers' structure by the concept of doping, sensitized CdS thin film by the bi-functional linker, and an environmentally friendly catalytic green agent. The Linker Assisted and Chemical Bath Deposition (LA-CBD) method was introduced as an innovative and effective hybrid sensitization approach. In the one-step synthesis process, Salvia dye, Ag, and 3-Mercaptopropionic acid (MPA) were used. Generally, the results for all samples displayed varying bandgap as achieved between (2.21-2.46) eV, hexagonal structure with considerably decreased strain level, broader grain size, and dramatically enhanced crystalline property. Hence, the rudimentary CdS/CZTS solar cell devices were fabricated for the application of these novel CdS films. Preliminary CZTS thin film solar cell fabrication results in the highest conversion efficiency of 0.266% obtained CdS + Salvia dye, indicating the potential use of the CdS films as a buffer layer for CZTS photovoltaic devices.

Mixed-reality technology for clinical communication: objective assessment of the HoloLens 2 as a clinical communication device in a simulated on-call scenario.

OBJECTIVE: Specialty on-call clinicians cover large areas and complex workloads. This study aimed to assess clinical communication using the mixed-reality HoloLens 2 device within a simulated on-call scenario. METHOD: This study was structured as a randomised, within-participant, controlled study. Thirty ENT trainees used either the HoloLens 2 or a traditional telephone to communicate a clinical case to a consultant. The quality of the clinical communication was scored objectively and subjectively. RESULTS: Clinical communication using the HoloLens 2 scored statistically higher than telephone (n = 30) (11.9 of 15 vs 10.2 of 15; p = 0.001). Subjectively, consultants judged more communication episodes to be inadequate when using the telephone (7 of 30) versus the HoloLens 2 (0 of 30) (p = 0.01). Qualitative feedback indicates that the HoloLens 2 was easy to use and would add value during an on-call scenario with remote consultant supervision. CONCLUSION: This study demonstrated the benefit that mixed-reality devices, such as the HoloLens 2 can bring to clinical communication through increasing the accuracy of communication and confidence of the users.

An in-depth analysis of nucleation and growth mechanism of CdS thin film synthesized by chemical bath deposition (CBD) technique.

The aim of this study is to acquire a deeper understanding of the response mechanism that is associated with the formation of CdS thin films. We presented an effective and new hybrid sensitisation technique, which involved the 1-step linker between the related chemical bath deposition (CBD) process and the traditional doping method during CBD for synthesising high-quality, CdS thin films. The mechanism for the combined synthesis of the films is also describes. CdS films were electrostatically bonded to soda-lime glass, causing the formation of the intermediate complexes [Cd(NH3)4]2+, which aided in the collision of these complexes with a soda-lime glass slide. In the one-step fabrication technique, 3-Mercaptopropionic Acid (MPA) was employed as a second source of sulphur ions and a linker molecule. Optical studies showed that the bandgap ranged between (2.26-2.52) eV. CdS + MPA films exhibited a uniform distribution of spherical molecules based on their morphological properties. After annealing, this approach significantly altered the electrical characteristics of CdS films. The CdS + MPA films displayed the highest carrier concentration whereas the CdS + Ag + MPA films exhibited the lowest resistivity, with a jump of 3 orders of magnitude.

New systematic study approach of green synthesis CdS thin film via Salvia dye.

In this study, we aimed to increase the knowledge regarding the response mechanisms which were associated with the formation of CdS thin films. CdS thin film remains the most appealing alternative for many researchers, as it has been a capable buffer material for effect in film based polycrystalline solar cells (CdTe, CIGSe, CZTS). The Linker Assisted and Chemical Bath Deposition (LA-CBD) technique, which combines the Linker Assisted (LA) technique and the chemical bath deposition (CBD) method for forming high quality CdS thin film, was presented as an efficient and novel hybrid sensitization technique. CdS films were bound to soda lime with the help of electrostatic forces, which led to the formation of the intermediate complexes [Cd (NH3)4]2+ that helped in the collision of these complexes with a soda lime slide. Salvia dye and as a linker molecule 3-Mercaptopropionic acid (MPA) was used in the one step fabrication technique. Optical results showed that the bandgap varied in the range of (2.50 to 2.17) eV. Morphological properties showed a homogeneous distribution of the particles that aspherical in shape in the CdS + MPA + Salvia dye films. This technique significantly affected on the electrical characterizations of CdS films after the annealing process. The CdS + Ag + MPA + Salvia dye films showed the maximum carrier concentration and minimum resistivity, as 5.64 × 10 18 cm-3 and 0.83 Ω cm respectively.

The One Minute Preceptor: A Vital Tool During COVID-19.

The One Minute Preceptor (OMP) model of teaching has an important role to play during the COVID-19 pandemic. It's quick and easy to learn and can be applied to any clinical setting. By responding directly to a student's needs, and building on the knowledge they already hold, the OMP is able to offer relevant and opportunistic teaching that the learner can immediately apply. Finally, the OMP can be taught in under two hours meaning medical staff not used to regularly teaching can develop the confidence to offer high quality educational interventions.

Suicidal behavior sociocultural factors in developing countries during COVID-19.

OBJECTIVES: Sociocultural factors in the aftermath of any pandemic can play a role in increasing suicidal behavior like suicidal ideation, suicidal attempts, or suicide. The authors discuss the risk and predisposing factors for suicidal ideation among mental health patients in four developing countries (Bangladesh, Colombia, India and Pakistan), this aims to grasp the heterogeneity of these motivators and to elaborate specific interventions regarding suicide in the COVID-19 pandemic. METHODS: We searched PubMed, Medline, and Google Scholar through March, 2021 for articles using a combination of the keywords and generic terms for suicide, suicide ideation, COVID-19, developing countries, low-middle-income countries, Sociocultural factors, Suicidal behavior, predisposing factors and predictive factors, for articles in English language only, and without publication time restriction. RESULTS: This narrative review summarizes the sociocultural risk and predisposing factors for suicidal behavior in developing countries during the COVID-19 pandemic. The findings reveal those factors such as fear of being infected, growing economic pressure, lack of resources due to lockdown are mostly responsible in the four countries for the current increase in suicides. There are a few cultural differences that are specified in the narrative. CONCLUSION: The COVID-19 pandemic is a public health challenge, in which prevention and intervention of suicidal behavior have been suboptimal, especially in low-middle-income countries. Based on literature results, we provide practical suggestions (e.g., reducing infodemic, specialized helplines, improving mental health services availability) in order to tackle main challenges of suicide prevention, such as lack of adequate manpower, fragile health system and poverty.

Molecularly Imprinted Polymers (MIPs) in Sensors for Environmental and Biomedical Applications: A Review.

Molecular imprinted polymers are custom made materials with specific recognition sites for a target molecule. Their specificity and the variety of materials and physical shapes in which they can be fabricated make them ideal components for sensing platforms. Despite their excellent properties, MIP-based sensors have rarely left the academic laboratory environment. This work presents a comprehensive review of recent reports in the environmental and biomedical fields, with a focus on electrochemical and optical signaling mechanisms. The discussion aims to identify knowledge gaps that hinder the translation of MIP-based technology from research laboratories to commercialization.

A global-scale screening of non-native aquatic organisms to identify potentially invasive species under current and future climate conditions.

The threat posed by invasive non-native species worldwide requires a global approach to identify which introduced species are likely to pose an elevated risk of impact to native species and ecosystems. To inform policy, stakeholders and management decisions on global threats to aquatic ecosystems, 195 assessors representing 120 risk assessment areas across all six inhabited continents screened 819 non-native species from 15 groups of aquatic organisms (freshwater, brackish, marine plants and animals) using the Aquatic Species Invasiveness Screening Kit. This multi-lingual decision-support tool for the risk screening of aquatic organisms provides assessors with risk scores for a species under current and future climate change conditions that, following a statistically based calibration, permits the accurate classification of species into high-, medium- and low-risk categories under current and predicted climate conditions. The 1730 screenings undertaken encompassed wide geographical areas (regions, political entities, parts thereof, water bodies, river basins, lake drainage basins, and marine regions), which permitted thresholds to be identified for almost all aquatic organismal groups screened as well as for tropical, temperate and continental climate classes, and for tropical and temperate marine ecoregions. In total, 33 species were identified as posing a 'very high risk' of being or becoming invasive, and the scores of several of these species under current climate increased under future climate conditions, primarily due to their wide thermal tolerances. The risk thresholds determined for taxonomic groups and climate zones provide a basis against which area-specific or climate-based calibrated thresholds may be interpreted. In turn, the risk rankings help decision-makers identify which species require an immediate 'rapid' management action (e.g. eradication, control) to avoid or mitigate adverse impacts, which require a full risk assessment, and which are to be restricted or banned with regard to importation and/or sale as ornamental or aquarium/fishery enhancement.

Work Based Assessments (WBAs) amongst UK medical trainees during the COVID-19 pandemic: How have we adapted?

Severe Acute Respiratory Syndrome Coronavirus type 2 (SARS-CoV-2) was recently identified as the RNA virus resulting in the Coronavirus disease (COVID-19). This was following cases of pneumonia identified in Hubei Province in China. The World Health Organisation (WHO) recently declared COVID-19 as a pandemic in March 2020. The COVID-19 pandemic has resulted in medical, financial and social disruption on an international scale. Such disruption has additionally impacted postgraduate medical training. This has been reflected in the attainment of Work Based Assessments amongst medical trainees in the United Kingdom.

Channel-hopping during surface electrical neurostimulation elicits selective, comfortable, distally referred sensations.

Objective.Lack of sensation from a hand or prosthesis can result in substantial functional deficits. Surface electrical stimulation of the peripheral nerves is a promising non-invasive approach to restore lost sensory function. However, the utility of standard surface stimulation methods has been hampered by localized discomfort caused by unintended activation of afferents near the electrodes and limited ability to specifically target underlying neural tissue. The objectives of this work were to develop and evaluate a novel channel-hopping interleaved pulse scheduling (CHIPS) strategy for surface stimulation that is designed to activate deep nerves while reducing activation of fibers near the electrodes.Approach.The median nerve of able-bodied subjects was activated by up to two surface stimulating electrode pairs placed around their right wrist. Subjects received biphasic current pulses either from one electrode pair at a time (single-channel), or interleaved between two electrode pairs (multi-channel). Percept thresholds were characterized for five pulse durations under each approach, and psychophysical questionnaires were used to interrogate the perceived modality, quality and location of evoked sensations.Main results.Stimulation with CHIPS elicited enhanced tactile percepts that were distally referred, while avoiding the distracting sensations and discomfort associated with localized charge densities. These effects were reduced after introduction of large delays between interleaved pulses.Significance.These findings demonstrate that our pulse scheduling strategy can selectively elicit referred sensations that are comfortable, thus overcoming the primary limitations of standard surface stimulation methods. Implementation of this strategy with an array of spatially distributed electrodes may allow for rapid and effective stimulation fitting. The ability to elicit comfortable and referred tactile percepts may enable the use of this neurostimulation strategy to provide meaningful and intuitive feedback from a prosthesis, enhance tactile feedback after sensory loss secondary to nerve damage, and deliver non-invasive stimulation therapies to treat various pain conditions.

The role of virtual reality in the changing landscape of surgical training.

BACKGROUND: The current coronavirus disease 2019 pandemic has caused unprecedented challenges to surgical training across the world. With the widespread cancellations of clinical and academic activities, educators are looking to technological advancements to help 'bridge the gap' and continue medical education. SOLUTIONS: Simulation-based training as the 'gold standard' for medical education has limitations that prevent widespread adoption outside suitably resourced centres. Virtual reality has the potential to surmount these barriers, whilst fulfilling the fundamental aim of simulation-based training to provide a safe, effective and realistic learning environment. CURRENT LIMITATIONS AND INSIGHTS FOR FUTURE: The main limitations of virtual reality technology include comfort and the restrictive power of mobile processors. There exists a clear developmental path to address these restrictions. Continued developments of the hardware and software set to deepen immersion and widen the possibilities within surgical education. CONCLUSION: In the post coronavirus disease 2019 educational landscape, virtual, augmented and mixed reality technology may prove invaluable in the training of the next generation of surgeons.

Enhancement of the Fouling Resistance of Zwitterion Coated Ceramic Membranes.

Ceramic membranes suffer from rapid permeability loss during filtration of organic matter due to their fouling propensity. To address this problem, iron oxide ultrafiltration membranes were coated with poly(sulfobetaine methacrylate) (polySBMA), a superhydrophilic zwitterionic polymer. The ceramic-organic hybrid membrane was characterized by scanning electron microscopy (SEM) and optical profilometry (OP). Membranes with and without polySBMA coating were subjected to fouling with bovine serum albumin solution. Hydraulic cleaning was significantly more effective for the coated membrane than for the non-coated one, as 56%, 66%, and 100% of the fouling was removed for the first, second, and third filtration cycle, respectively. Therefore, we can highlight the improved cleaning due to an increased fouling reversibility. Although some loss of polymer during operation was detected, it did not affect the improved behavior of the tested membranes.

An Inventive Report of Inducing Apoptosis in Non-Small Cell Lung Cancer (NSCLC) Cell Lines by Transfection of MiR-4301.

BACKGROUND: Based on recent studies, new therapeutic strategies have been developed for cancer treatment using microRNAs (miRNAs). With this view, miRNAs manipulating techniques can be considered as novel therapeutic prospects for cancer treatment. In this study, we evaluated the expression of miR-4301 in human lung cancer cell lines and investigated its potential role in cell proliferation and tumor suppression on Non-Small Cell Lung Cancer (NSCLC) cells. METHODS: We used quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) to examine the level of miR- 4301 expression in human lung cancer cell lines (A549, QU-DB) and non-malignant lung epithelial cells (HFLF-PI5). Then, we investigated the effect of miR-4301 by transfecting it into these cell lines and probing for cancer cell viability and apoptosis using the MTT assay, flow cytometry and immunofluorescence staining. RESULTS: Our results showed that the expression level of miR-4301 was significantly reduced in human lung cancer cell lines (P<0.001). When miR-4301 was transfected in lung cancer cells, their cell proliferation was suppressed and apoptosis induced. This decline in cell survival was confirmed by the MTT assay. Transfection of miR-4301 caused an increase in early and late apoptotic cells in all lung cancer cell lines tested. CONCLUSIONS: Our findings show that miR-4301 may act as a lung cancer suppressor through targeting of proteins involved in cell proliferation and survival. For this reason, targeting miR-4301 may provide a new strategy for the diagnosis and treatment of patients with this deadly disease. This article is protected by copyright. All rights reserved.

The moderating role of social support for marital adjustment, depression, anxiety, and stress: Evidence from Pakistani working and nonworking women.

BACKGROUND: This study examined how social support moderates the prolongation of mental distress related to depression, anxiety, stress, and marital adjustment in working and nonworking women. The study aimed to reveal the relationship between social support and mental health issues associated with depression, anxiety, stress, and marital adjustment among females. METHODS: This research study is among the few studies performed in a Pakistani context and was conducted in 2017 to measure affective disorders among nonworking and working married females. Questionnaires were distributed among 500 targeted women, and valid responses were received from married working women in hospitals, banks, and multinational companies, and married nonworking women from residential areas of Islamabad and Rawalpindi, Pakistan. A cross-sectional design with purposive sampling was adapted for this research, and three scales were used to measure stress, anxiety, depression, social support, and marital adjustment and its social and cultural implications among the sampled population. RESULTS: Social support was positively and significantly associated with marital adjustment, although it showed a negative association with anxiety, depression, and stress in working and nonworking women; this finding reflects the better mental health of the study population. The findings proved that marital adjustment has a negative relation with depression and anxiety in married working and nonworking females. Social support acts as a moderator for marital cohesion, affection, stress, and depression, and the results reflected that nonworking women with higher marital cohesion and affection showed less stress and depression because of social support. LIMITATIONS: The findings of this sample cannot be generalized to the whole population as they are specific to the targeted respondents only. CONCLUSION: The study revealed that women's mental health is affected by psychological distress caused by depression, anxiety, stress, social and cultural norms, and their implications. Lower stress and depression lead to better mental health as ostensive social support may help to explain the relationship between depression, anxiety, and stress.

Image-guided transnasal endoscopic fine needle aspiration or biopsy of parapharyngeal space tumours.

BACKGROUND: Parapharyngeal space biopsy is an important investigation in the management of parapharyngeal space tumours. These tumours are relatively rare and the surgeon is often faced with a wide range of differential diagnoses. There are several ways to access the parapharyngeal space, with varying degrees of associated morbidity. METHODS: This paper describes a seldom used, but a simple and safe, image-guided endoscopic approach to parapharyngeal space biopsy that enables tissue to be obtained transnasally. The procedure is conducted under general anaesthesia using computed tomography image guidance via the LandmarX system, with transnasal access to the parapharyngeal space achieved using a sampling needle. RESULTS: This procedure is relatively simple, safe and reproducible. It is a less invasive approach to parapharyngeal space biopsy, and one which has been successfully used by the senior author for years without any significant morbidity. CONCLUSION: Transnasal image-guided endoscopic aspiration or biopsy of the parapharyngeal space is a novel technique that has not been previously described.

Photonic Molecularly Imprinted Polymer Film for the Detection of Testosterone in Aqueous Samples.

The detection of testosterone in aqueous solutions is a difficult task due to the low concentration levels that are relevant in environmental and physiological samples. Current analytical methods are expensive and/or complex. To address this issue, we fabricated a molecularly imprinted polymer (MIP) photonic film for the detection of testosterone in water. The films were obtained using colloidal crystals as templates for the pore morphology. Monodispersed silica particles with an average diameter 330 nm were used to obtain the colloidal crystal by vertical deposition. A solution of acrylic acid with testosterone as the imprinted template was infiltrated in the colloidal crystal and polymerized via bulk polymerization; the particles were then removed by acid etching and the testosterone eluted by a suitable solvent. The material was characterized by FTIR, swelling experiments and microscopy; MIPs were investigated by equilibrium rebinding, kinetics and reuse experiments. The results showed that the MIPs exhibited selectivity to the template, a 30-min equilibration time and stability after at least six cycles of use and regeneration. After incubation, the reflectance spectra of the films showed a shift of the Bragg diffraction peak that correlated with testosterone concentration in the 5⁻100 ppb range.

Mechanical fatigue resistance of an implantable branched lead system for a distributed set of longitudinal intrafascicular electrodes.

OBJECTIVE: A neural interface system has been developed that consists of an implantable stimulator/recorder can with a 15-electrode lead that trifurcates into three bundles of five individual wire longitudinal intrafascicular electrodes. This work evaluated the mechanical fatigue resistance of the branched lead and distributed electrode system under conditions designed to mimic anticipated strain profiles that would be observed after implantation in the human upper arm. APPROACH: Custom test setups and procedures were developed to apply linear or angular strain at four critical stress riser points on the lead and electrode system. Each test was performed to evaluate fatigue under a high repetition/low amplitude paradigm designed to test the effects of arm movement on the leads during activities such as walking, or under a low repetition/high amplitude paradigm designed to test the effects of more strenuous upper arm activities. The tests were performed on representative samples of the implantable lead system for human use. The specimens were fabricated using procedures equivalent to those that will be used during production of human-use implants. Electrical and visual inspections of all test specimens were performed before and after the testing procedures to assess lead integrity. MAIN RESULTS: Measurements obtained before and after applying repetitive strain indicated that all test specimens retained electrical continuity and that electrical impedance remained well below pre-specified thresholds for detection of breakage. Visual inspection under a microscope at 10× magnification did not reveal any signs of damage to the wires or silicone sheathing at the stress riser points. SIGNIFICANCE: These results demonstrate that the branched lead of this implantable neural interface system has sufficient mechanical fatigue resistance to withstand strain profiles anticipated when the system is implanted in an arm. The novel test setups and paradigms may be useful in testing other lead systems.