External Barrier Research Articles

A qualitative study

A qualitative study

Efficient Near-Infrared Organic Photodetectors with Spectral Response up to 1600 nm for Accurate Alcohol Concentration Detection

The development of near-infrared organic photodetectors (NIR-OPDs) in 1000-1700 nm is essential for medical monitoring, food quality inspection, machine vision, and biomedical imaging. However, when solving the high dark current density (JD) in bulk-heterojunction (BHJ) NIR-OPDs based on narrow-bandgap systems, it is often accompanied by photocurrent loss, which is a great challenge in achieving high-performance NIR-OPDs. Here, an ideal hybrid pseudo-PHJ (planar-heterojunction)/BHJ structure is proposed to overcome this challenge, which is introducing the N2200 layer between the cathode and BHJ. The introduction of the N2200 raises the external charge injection barrier and reduces the trap density, thus achieving significant suppression of JD (6.22 × 10-7 A cm-2 at -0.2 V bias, about 2 orders of magnitude lower compared to the BHJ NIR-OPDs). Meanwhile, the hybrid structure combines the advantages of PHJ and BHJ, thus maintaining a high photocurrent, resulting in responsivity and detectivity of 18.71 mA W-1 and 4.19 × 1010 Jones, respectively, at 1400 nm at -0.2 V bias, which is superior to the performance of BHJ NIR-OPDs. And the hybrid structured NIR-OPDs are proven to rapidly quantify the alcohol content of mixtures to within 2% accuracy, which exhibits great potential for application in the food and pharmaceutical industries.

Cetacean diversity around the Mozambique Channel island of Mayotte (Comoros archipelago)

The Indian Ocean was designated as a whale sanctuary in 1979. While cetacean research has been conducted throughout the sanctuary, few studies have been conducted to assess the diversity, distribution and abundance of cetaceans inhabiting the waters surrounding the islands in the northern Mozambique Channel. In order to contribute to management and conservation efforts in this area, a series of small boatbased surveys were undertaken around the island of Mayotte from July 2004 to August 2005 to assess the diversity of cetaceans in the lagoon and surrounding waters, i.e. external barrier reef slope, insular slope (200-1,000m) and oceanic (>1,000m) waters. During this period, more than 284 hours were spent at sea on-effort and 17 cetacean species were recorded around Mayotte (n=286 sightings). One mysticete (1 Balaenopterid) and sixteen odontocetes (1 Kogid, 1 Physeterid, 13 Delphinids and 2 Ziphiids) were observed: spinner dolphin, n=118; pantropical spotted dolphin, n=61; Indo-Pacific bottlenose dolphin, n=44; humpback whale, n=37; melon-headed whale, n=5; Blainville’s beaked whale, n=4; Indo-Pacific humpback dolphin, n=4; common bottlenose dolphin, n=2; Risso’s dolphin, n=2; false killer whale, n=2; dwarf sperm whale, n=2; sperm whale, n=1; pygmy killer whale, n=1; short-finned pilot whale, n=1; Fraser’s dolphin, n=1; and Longman’s beaked whale, n=1. In addition to these 17 species recorded during dedicated surveys, two other cetacean species were observed opportunistically and subsequently identified as the Ginkgo-toothed beaked whale and the blue whale. The relatively large diversity of cetaceans around Mayotte is attributed to the wide range of marine habitats, such as coastal, reef-associated and oceanic, within close proximity to one another.

Role of PI3K-AKT Pathway in Ultraviolet Ray and Hydrogen Peroxide-Induced Oxidative Damage and Its Repair by Grain Ferments.

UV and external environmental stimuli can cause oxidative damage to skin cells. However, the molecular mechanisms involved in cell damage have not been systematically and clearly elucidated. In our study, an RNA-seq technique was used to determine the differentially expressed genes (DEGs) of the UVA/H2O2-induced model. Gene Oncology (GO) clustering and the Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway analysis were performed to determine the core DEGs and key signaling pathway. The PI3K-AKT signaling pathway was selected as playing a part in the oxidative process and was verified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). We selected three kinds of Schizophyllum commune fermented actives to evaluate whether the PI3K-AKT signaling pathway also plays a role in the resistance of active substances to oxidative damage. Results indicated that DEGs were mainly enriched in five categories: external stimulus response, oxidative stress, immunity, inflammation, and skin barrier regulation. S. commune-grain ferments can effectively reduce cellular oxidative damage through the PI3K-AKT pathway at both the cellular and molecular levels. Some typical mRNAs (COL1A1, COL1A2, COL4A5, FN1, IGF2, NR4A1, and PIK3R1) were detected, and the results obtained were consistent with those of RNA-seq. These results may give us a common set of standards or criteria for the screen of anti-oxidative actives in the future.

Smart Mask as Wearable for Post-Pandemic Personal Healthcare.

A mask serves as a simple external barrier that protects humans from infectious particles from poor air conditions in the surrounding environment. As an important personal protective equipment (PPE) to protect our respiratory system, masks are able not only to filter pathogens and dust particles but also to sense, reflect or even respond to environmental conditions. This smartness is of particular interest among academia and industries due to its potential in disease detection, health monitoring and caring aspects. In this review, we provide an overlook of the current air filtration strategies used in masks, from structural designs to integrated functional modules that empower the mask's ability to sense and transfer physiological or environmental information to become smart. Specifically, we discussed recent developments in masks designed to detect macroscopic physiological signals from the wearer and mask-based disease diagnoses, such as COVID-19. Further, we propose the concept of next-generation smart masks and the requirements from material selection and function design perspectives that enable masks to interact and play crucial roles in health-caring wearables.

Multifunctional ZnFeO4-Based Antibiotic Cross-Linked Nanoplatform for Magnetically Targeted Treatment of Microbial Biofilms

During the infections of wounds or medical device surfaces, bacteria such as Pseudomonas aeruginosa are prone to forming biofilms which prevent the penetration of antimicrobial agents. Herein, a combined therapy using bactericidal nano-micelles Ce6-ZnFeO4@ABCsi-micelles was developed that employed colistin cross-linked Pluronic micelles as a carrier, with the magnetic metal oxide ZnFeO4 and photosensitizer dihydroporphyrin (Ce6) encapsulated in the core of micelles. Driven by an external magnetic field, the nano-micelles could penetrate the external barrier of the biofilm. Reactive oxygen species (ROS) generated by the photosensitizer Ce6 disrupted the barrier of the biofilm, which facilitated the distribution of the Ce6 and colistin antibiotics into the biofilm, realizing a 99.5% clearance rate of bacteria. Using such a combination of chemotherapy and photodynamic therapy, Ce6-ZnFeO4@ABCsi-micelles could clear wound infection in a murine abscess model, owing to the targeted driving effect of the external magnetic field, along with the chemotherapeutic effect of colistin and the photodynamic effect of Ce6. This design provides an effective targeted therapeutic strategy to address biofilm infections.

Химический состав, структура и микротвердость многослойных высокотемпературных покрытий

Introduction. Plasma spraying is one of the modern and effective methods for coatings application for various purposes and compositions. With the help of thermal plasma flows, it is possible to spray almost any powder materials (ceramic, metal, metal-ceramic). Plasma spraying of multilayer protective coatings can be successfully used to increase the durability of pierced mandrels, which are the main tool in the production of hollow billets. The purpose of this work is to study the chemical composition, structure, and microhardness of multilayer high-temperature coatings of two different compositions deposited by plasma spraying, which are supposed to be used to increase the durability of pierced mandrels. Materials and research methods. The deposition of multilayer coatings of two compositions was carried out on a plasma-powder spraying unit with contact excitation of an arc discharge UPN-60KM TSP2017. Coatings were obtained by sequential deposition of three layers with different powder compositions. After deposition of all three coating layers, oxidative annealing was carried out at a temperature of 900°C to form a dense scale layer of FeO + Fe2O3 + Fe3O4 on the surface. The chemical composition of the coatings was studied by X-ray microanalysis using a TESCAN scanning electron microscope with an OXFORD attachment. The microstructure of the coatings was studied using a NEOPHOT metallographic microscope. Phase X-ray diffraction analysis was performed on a SHIMADZU diffractometer in Kα chromium radiation. Microhardness was measured on a LEICA hardness tester at a load of 50 g. Results and discussion. The nature of the distribution of chemical elements over the thickness of the coating, consisting of four layers, is established: an inner metal layer that provides protection against high-temperature corrosion; a transitional metal layer designed to equalize the thermal properties between the layers; α-Fe metal oxide layer and iron oxides and external thermal barrier oxide layer FeO + Fe2O3 + Fe3O4. Coatings are characterized by a non-uniform distribution of structural components and microhardness over its thickness. The microhardness of the inner layer reaches 1,400 HV0.05, the transition layer is 800 HV0.05, and the metal oxide layer is 300 HV0.05.

Perceived Barriers and Facilitators to Psychotherapy Utilisation and How They Relate to Patient's Psychotherapeutic Goals.

Access to psychotherapy is still limited by various barriers, and little is known about the facilitating circumstances. This study aims to assess self-reported barriers and facilitators to psychotherapy utilisation in private practice and how these access factors relate to psychotherapy goals as formulated by patients. The dataset consists of 21 face-to-face semi-structured interviews with patients treated by psychotherapists in private practice in Austria. Data were analysed using qualitative content analysis, including a frequency count of the number of codings to analyse relations between categories. A critical external barrier theme was unaffordable psychotherapy and confusion about how the Austrian funding system works. A negative experience with psychotherapy prior to the current one, such as not being understood and answered well enough by one's therapist, was a frequently reported internal barrier. Individuals who faced more internal barriers and more external facilitators in seeking therapy, such as moral support from significant others and professionals, formulated less elaborate treatment goals. Although the study was carried out amid the COVID-19 pandemic, the pandemic played a minor role in patients' self-reported barrier and facilitator themes.

English Language Teacher as an External Barrier among Foreign Language Learners' Communicative Interaction: A Case Study of South Punjab

The key objective of the study was to 'explore EFL students' approaches towards teaching obstructions to 'improve students' communicative skill and to reconnoitre the impact of EFL learners' attitudes about teaching hurdles to increase students' communicative skill at BS level in South Punjab'.To execute the basic aim of this research uses the mixed method approach and for the proper execution of this work the researcher collected data through a questionnaire. Research data were analyzed using Statistical Package for Social Sciences (SPSS). This research concludes that the majority of the learners agreed that they feel hesitant in speaking English with class fellows as their English language teacher hardly implies spoken language improving strategies in class, as their teacher gazes at them for their making mistakes, they cannot keep on speaking, when learners make mistakes, instead of motivating, the teacher makes them silent, their English language teacher delivers lecture in Urdu or in his native language which mars the communicative competence, their English language teacher never uses audio-visual aids in the class to improve their communication skill.

Perception of faculty towards e-learning vs. traditional learning in a public sector medical college.

Objective: To evaluate the perception of medical teaching faculty of a public sector medical college in Pakistan and the barriers in e-learning methodologies according to faculty’s opinion. Study Design: Analytical Cross-Sectional Study. Setting: Department of Medical Education, Sahiwal Medical College Sahiwal. Study Period: 1st April 2020 to 30th April 2020. Material & Methods: The questionnaire was sent to all the faculty members through Whatsapp due to COVID-19 pandemic in Pakistan. Mean scores were calculated by using SPSS-26. Results: A total of sixty six faculty members responded to the questionnaire while it was sent to all 72. So the response rate of our study is 91.66%. According to our results, external sources barrier questions were found to be of highest mean value of 10.64 with standard deviation of 4.64. Internal source barriers were found to have least of the means value of 5.39 with standard deviation of 2.41. Motivation related to e-learning was with highest mean score of 2.67 and with standard deviation of 0.591. Lack of central policy was found to be of major concern by the respondents with mean value of 1.15 and standard deviation of 0.361. Conclusion: This study found that motivation towards e-learning as the most dominant factor. Also external sources barriers were predominately revealed in the college such arrangements are required to speedily guarantee that fast web get to and dependable systems are accessible at the higher education institutions.

English Grammar Rules as an External Barrier Faced by EFL Students for Effective Communication

The key objective of the study was to 'investigate English grammar rules as an external barrier faced by EFL students for effective communication and to examine the impact of English grammar rules as an external barrier faced by EFL students for effective communication'. To fulfil the preceding purpose this research utilizes the mixed method approach and for the proper execution of this work, the researcher collected data through a questionnaire. Research data were analyzed using Statistical Package for Social Sciences (SPSS). The results of data analysis illustrate the respondents of the study responded with medium to low degree mean values. The results of the current study reveal that most of the foreign language learners indicated that in the two preceding situations and atmospheres the external barrier such as silent letters, difficult spellings, wrong pronunciation, variation in pronunciation due to complex spelling systems, pronunciation of words matches with their spellings, and lengthy words learners feel a high degree of difficulty and English grammar rules work as a hurdle for effective communication.

Massive Distance Education: Barriers and Challenges in Shifting to a Complete Online Learning Environment.

The global pandemic has dramatically changed how the world functions and impacted all sectors of society including all educational institutions. Government and educators respond with immediate online teaching and learning for all students. Massive distance education has been drawn into the picture to provide non-stop learning in most countries worldwide. This study focuses on examining different orders of barriers educators have encountered during the Covid-19 pandemic. The barriers to massive online teaching and learning included the first-order barrier (technological or external barrier), the second-order barrier (internal barrier or teachers' and parents' beliefs), the third-order barrier (design thinking barrier), and the 2.5th order barrier (the classroom management barrier). Both teachers and students are suffering from unstable or limited internet connectivity and it directly hinders students' rights in the massive online education. Teachers are facing the need for sudden pedagogical redesign while parents are enduring the burden of providing all kinds of support for their children's online learning at home. Some learners are experiencing videoconferencing fatigue and struggling with overwhelming resources and an excessive amount of technology time. This study also identifies a group of forgotten learners, the videoconferencing refugees, who have limited access to the Internet and lost their learning opportunities. From a global perspective, shifting to massive online education may be possible with all four orders of barriers being overcome.

Quantum reflection of dark solitons scattered by reflectionless potential barrier and position-dependent dispersion.

We investigate theoretically and numerically quantum reflection of dark solitons propagating through an external reflectionless potential barrier or in the presence of a position-dependent dispersion. We confirm that quantum reflection occurs in both cases with a sharp transition between complete reflection and complete transmission at a critical initial soliton speed. The critical speed is calculated numerically and analytically in terms of the soliton and potential parameters. Analytical expressions for the critical speed were derived using the exact trapped mode, time-independent, and time-dependent variational calculations. It is then shown that resonant scattering occurs at a critical speed, where the energy of the incoming soliton is resonant with that of a trapped mode. Reasonable agreement between analytical and numerical values for the critical speed is obtained as long as a periodic multisoliton ejection regime is avoided.

Generation and characterization of hair-bearing skin organoids from human pluripotent stem cells.

Human skin uses millions of hairs and glands distributed across the body surface to function as an external barrier, thermoregulator and stimuli sensor. The large-scale generation of human skin with these appendages would be beneficial, but is challenging. Here, we describe a detailed protocol for generating hair-bearing skin tissue entirely from a homogeneous population of human pluripotent stem cells in a three-dimensional in vitro culture system. Defined culture conditions are used over a 2-week period to induce differentiation of pluripotent stem cells to surface ectoderm and cranial neural crest cells, which give rise to the epidermis and dermis, respectively, in each organoid unit. After 60 d of incubation, the skin organoids produce hair follicles. By day ~130, the skin organoids reach full complexity and contain stratified skin layers, pigmented hair follicles, sebaceous glands, Merkel cells and sensory neurons, recapitulating the cell composition and architecture of fetal skin tissue at week 18 of gestation. Skin organoids can be maintained in culture using this protocol for up to 150 d, enabling the organoids to be used to investigate basic skin biology, model disease and, further, reconstruct or regenerate skin tissue.

THE IMPACT OF SPORT ON THE HEALTH AND IMPROVEMENT OF MENTAL HYGIENE AMONG THE STUDENT POPULATION – A SYSTEMATIC REVIEW

Due to its appeal, sport has always been in the service of various social fields, both in a negative and a positive sense. A sedentary lifestyle has become noticeably dominant among students. The most frequent external barrier for taking part in physical activities among the student population is a lack of time due to their schedules or due to familial or other obligations. The aim of the research was to use a critical analysis of existing studies and a generalization of the results of all the analysed papers which studied the effectiveness of sport to show the effects of sport and physical activity (PA) on the improvement of the mental hygiene among the student population. The literature was compiled by searching the following databases: Medline, Google Scholar, Web of Science and PubMed. The database search resulted in 198 papers of which 15 were included in the systematic review. The participants included in the systematic review were adults who attended class and were university students. An awareness of health and the positive effects of PA can be a decisive factor for motivating people to become physically more active. PA can help in the prevention and continuation of psychological wellbeing.

Barriers to innovative activity of enterprises in the sustain development in times of crisis

In today's modern economy, and according to the growing economic, social, and environmental challenges, it is becoming more and more important for organizations to strive towards sustainable development. Any innovation is related to the sustainable development of an organization, and these innovations concern changes in the management, technological, and ecological activities. There are some specific and significant barriers that can have an impact on innovation, and in consequence, on the sustainable development of an organization. Especially in the recent crisis caused by the Covid19 pandemic and currently hostilities in Ukraine.In the article the Author attempted to answer three research questions: What are the main barriers to implementing innovation in researched companies? Do the innovations affect the sustainable development of these organizations? Have the recent years of the pandemic strengthened the barriers to innovation? The aim of the article is to present examples of barriers to innovation in interviewed companies (identification and classification of barriers). For this purpose, the Author conducted relevant literature reviews, inductive and deducting reasoning and 12 in-depth interviews (IDI).On the basis of the conducted research, the barriers to innovative activity indicated by owners/managers were divided into external and internal. Within internal barriers, there were distinguished mainly organizational, human resources and financial barriers. Among external barrier ware identified barriers concerning legal barriers, cost and financial as well as market barriers.Is seems to be significant to analyze and identify barriers to innovative activity in the sustainable development especially in connection with crisis situations caused by the pandemic and the war in Ukraine. This article can fill the gap in this field and lead to further theoretical and empirical research. The results of the study may be useful to other researchers as well as executives in the studied organization and other public sector institutions.

Depletion Induced Demixing and Crystallization in Binary Colloids Subjected to an External Potential Barrier.

Depletion interaction plays an important role in determining the structural and dynamical properties of binary colloidal mixtures. We have investigated the effect of the attractive depletion interaction between an external potential barrier and larger species in the binary mixture on the phase behavior of a binary colloidal mixture using canonical-isokinetic ensemble molecular dynamics simulations. The demixing of the binary mixture due to this depletion interaction increases as the volume fraction increases, and a pure phase of larger particles forms in the region of the potential barrier. The local density of this pure phase is high enough that a face centered cubic crystalline domain is formed at this region. This crystalline phase diffuses perpendicular to the external potential barrier, indicating that moving crystals can be obtained in an equilibrium system. The temperature dependence of diffusivity of larger particles is non-Arrhenius and changes from sub-Arrhenius to super-Arrhenius as the volume fraction increases. This crossover from sub-Arrhenius to super-Arrhenius diffusion coincides with the crystalline formation near the potential barrier.

Understanding help-seeking barriers after Gender-Based Violence: Validation of the Barriers to Help Seeking-Trauma version (BHS-TR)

It is a devastating and tragic estimate that 35% of women worldwide have experienced either physical or sexual violence at some point in their lives (United Nations, 2015) (referred to hereafter as Gender-Based Violence, or GBV). While most research focuses on reducing violence, understanding power and control in families, and evaluating services, this study focuses on overcoming trauma recovery barriers. We document the development and psychometric properties of the development of the Barriers to Help Seeking for Trauma Scale (BHS-TR) scale conducted with 309 GBV survivors. EFA and CFA confirmed a 7-factor solution that explained 68.4% of the variance, with an alpha reliability of 0.87. Factors were Shame, Frozen/Confused, Problem Management beliefs, Unavailable, Financial Concerns, Discrimination, and Constraints. Convergent validity was found with Sense of Coherence (SOC) and Beliefs about Mental Illness (BMI), and external validity was found with all the subscales and depression/PTSD except Problem Management beliefs. Cluster analysis was used to confirm that the barriers factors grouped into Internal and External Barrier dimensions. Regression showed that BMI predicted 24% of External Barriers variance, and SOC predicted 20% of the variance of the Internal barriers. Implications include the need to understand the breadth of help-seeking survivors engage in, differentiate the varieties of barriers from shame and stigma, and work with survivors “where they are” to address perceived barriers.

Synthesis, characterization, and molecular docking analysis of Chitosan-gr-Polysulphanilic acid as antimicrobial water-soluble polymers

As a hydrophilic polysaccharide derived from chitin, chitosan has a broad antibacterial spectrum against bacteria and fungi. Activity depends on polymer molecular weight (MW) and degree of acetylation (DA). The activity of polysulphanilic acid as an antimicrobial is very poor. Chitosan graft polysulphanilic acid was synthesized and characterized by some instrumental tools, such as UV-visible, IR spectroscopy, SEM, XRD, and TGA. The obtained graft was introduced to use as an antimicrobial. The obtained data reveals a good antimicrobial activity for different types of the organism as Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. For the effect of chitosan, three antibacterial mechanisms are proposed. The ionic surface interaction results in wall cell leakage the inhibition of the mRNA and protein synthesis via the penetration of chitosan into the nuclei of the microorganisms; and the formation of an external barrier, chelating metals, and provoking the suppression of essential nutrients to microbial growth. It is likely that all events occur simultaneously but at different intensities. Chitosan–graft–polysulphanilic acid as a water-soluble polymeric material gives higher efficiency than chitosan and the used references for both gram-positive and gram-negative bacteria. Also, The molecular docking analysis showed that Chitosan-gr-Polysulphanilic acid interacts with the five receptors via different types of interactions, such as hydrogen bonding, van der Waals, and pi-interactions with high binding energies. Also, Chitosan–graft–poly sulphanilic acid has better ADMET and physicochemical properties. So, Chitosan–graft–poly sulphanilic acid can be used as an antimicrobial agent.

Unconventional pairing in few-fermion systems tuned by external confinement

We study the ground-state properties of a two-component one-dimensional system of a few ultra-cold fermions with attractive interactions. We show that, by ramping up an external potential barrier felt by one of the components, it is possible to induce regions of exotic superfluid phases, characterized by a tunable finite net momentum of the Cooper pair, without changing the overall spin populations. We show that these phases, which are the few-body analogs of the celebrated Fulde-Ferrell-Larkin-Ovchinnikov state, can be distinguished by analyzing a specific two-particle correlation encoded in the noise correlation function. Our theoretical results can be addressed in current experiments with cold atoms confined in spin-selective optical traps.