A Numerical Study of the Flexural Behavior of Concrete Beams Reinforced with AFRP Bars

In this study, analytical and numerical investigations were extensively conducted to evaluate the flexural behavior of concrete beams reinforced with aramid fiber-reinforced polymer (AFRP) rebars. The AFRP-reinforced concrete beams were analyzed using the separated finite element method containing different elements for concrete and reinforcement. In addition, this study used two different effective moment of inertia expressions to estimate the load-deflection responses and the service-load deflections of the beams. The service-load deflections of the AFRP-reinforced concrete beams obtained from the finite element analysis were in close agreement with those from the effective moment of inertia expressions. The numerical ultimate moments also correlated well with the analytical values of concrete stress-strain models. Numerical analyses, which hardly predict the sudden reduction in the flexural rigidity of FRPreinforced concrete beams due to the crushing of cover concrete, were shown to provide somewhat conservative deflection estimates.Представлены результаты аналитических и численных исследований, целью которых является определение изгибных характеристик железобетонных балок, упрочненных полимерными стержнями из армированных волокон. С помощью специального метода конечных элементов, включающего различные элементы для процессов бетонирования и армирования, провели анализ железобетонных балок, армированных полимерными стержнями. Для оценки характеристик прогиба под действием нагрузки и прогиба балки под действием рабочей нагрузки использовали два различных уравнения эффективного момента инерции. Значения прогиба железобетонных балок с полимерными стержнями под действием рабочей нагрузки, полученные конечноэлементным методом, хорошо сопоставляются со значениями из уравнений момента инерции. Численные значения разрушающего момента также хорошо согласуются с аналитическими значениями, полученными в результате применения модели зависимости деформации от напряжения для бетона. Для консервативной оценки прогиба представлены результаты численного анализа, которые почти не спрогнозировали внезапное уменьшение показателя жесткости при изгибе железобетонных балок с полимерными стержнями вследствие разрушения защитного слоя бетона.Представлено результати аналітичних і чисельних досліджень, метою яких є визначення згинальних характеристик залізобетонних балок, зміцнених полімерними стрижнями з армованих волокон. За допомогою спеціального методу скінченних елементів, що включає різні елементи для процесів бетонування й армування, проаналізовано залізобетонні балки, армовані полімерними стрижнямі. Для оцінки характеристик прогину під дією навантаження і прогину балки під дією робочого навантаження використовували два різних рівняння ефективного моменту інерції. Значення прогину залізобетонних балок із полімерними стрижнями під дією робочого навантаження, отримані скінченно-елементним методом, добре зіставляються зі значеннями з рівнянь моменту інерції. Числові значення руйнівного моменту також добре узгоджуються з аналітичними значеннями, отриманими по моделі залежності деформації від напруження для бетону. Для консервативної оцінки прогину представлено дані чисельного аналізу, які майже не спрогнозували раптове зменшення показника жорсткості при згині залізобетонних балок із полімерними стрижнями внаслідок руйнування захисного шару бетону

Management of spontaneous pneumothorax in patients with COVID-19.

ObjectivesThe coronavirus disease 2019 (COVID-19) pneumonia may cause cystic features of lung parenchyma which can resolve or progress to larger blebs. Pneumothorax was more likely in patients with neutrophilia, severe lung injury and a prolonged clinical course. The timely diagnosis and management will reduce COVID-19-associated morbidity and mortality.MethodsWe present 11 cases of spontaneous pneumothorax managed with chest tube thoracostomy or high-dose oxygen therapy. Isolated spontaneous pneumothorax was detected in all cases.ResultsEight cases were male and 3 cases were female. There were bilateral ground-glass opacities or pulmonary infiltrates in the parenchyma of the 10 cases. We detected neutrophilia, lymphopaenia and increased C-reactive protein, Ferritin, lactate dehydrogenase, D-Dimer, interleukin-6 levels in almost all cases. Chest tube thoracostomy was sufficient to treat pneumothorax in our 9 of case. In 2 cases, pneumothorax healed with high-dose oxygen therapy. Favipiravir and antibiotic treatment were given to different 10 patients. In our institution, all patients with COVID-19 infection were placed on prophylactic or therapeutic anticoagulation, unless contraindicated. The treatments of patients diagnosed with secondary spontaneous pneumothorax during the pandemic period and those diagnosed with secondary spontaneous pneumothorax in the previous 3 years were compared with the durations of tube thoracostomy performed in both groups.ConclusionsThe increased number of cases of pneumothorax suggests that pneumothorax may be a complication of COVID-19 infection. During medical treatment of COVID-19, pneumothorax may be the only reason for hospitalization. Although tube thoracostomy is a sufficient treatment option in most cases, clinicians should be aware of the difficulties that may arise in diagnosis and treatment

The Teaching and Learning Cultural Competence in a Multicultural Environment (CCMEn) Model

Background: Within the European higher education context, students and lecturers are encouraged to engage in teaching and learning activities abroad. This frequently involves using a second language and being exposed to students and lecturers from culturally different backgrounds. Objective: To design a model for teaching and learning cultural competence in a multicultural environment (CCMEn). Design: Theory development from empirical experience, research, and scholarly works. Method: This model was developed based on our experience of teaching and learning cultural competence in a multicultural environment in a nursing education context; it rests on three pillars, namely, Coyle's Content and Language Integrated Learning educational approach, the concept of social and emotional learning, as defined by the Collaborative for Academic, Social and Emotional Learning, and the existing literature surrounding teaching and learning cultural competence in higher education. Results: The CCMEn model is intended to guide the process of teaching and learning cultural competence in a multicultural environment through the use of a second language and has been adapted from existing educational approaches and theory. Conclusion: Teaching and learning in multilingual and multicultural contexts in Europe is becoming more common. Students who learn alongside students and teachers from different cultural backgrounds need to be supported from an academic, linguistic and socioemotional perspective. We believe that the CCMEn model can serve as a guide to enhancing student learning in this context

Nursing lecturers’ perception and experience of teaching cultural competence: a european qualitative study

Cultural competence is an essential component in providing effective and culturally responsive healthcare services, reducing health inequalities, challenging racism in health care and improving patient safety, satisfaction and health outcomes. It is thus reasonable that undergraduate nursing students can develop cultural competency through education and training. The aim of this paper was to investigate nursing lecturers’ perception and experience of teaching cultural competence in four undergraduate nursing programs. A phenomenological approach was selected to illicit nursing lecturers’ perception of culture and experience of teaching cultural competence. Semi-struc-tured personal interviews were held with a sample of 24 lecturers from four European universities. The anonymized transcripts were analyzed qualitatively following Braun and Clark’s phases for thematic analysis. Six themes and fifteen subthemes emerged from thematic analysis of the tran-scripts. Cultural competence was not explicitly integrated in the nursing curricula. Instead, the lecturers used mainly examples and case studies to illustrate the theory. The integration of cultural content in the modules was unplanned and not based on a specific model. Nursing programs should be examined to establish how cultural content is integrated in the curricula; clear guidelines and standards for a systematic integration of cultural content in the nursing curriculum should be de-veloped

Identification of damaged wheat kernels and cracked-shell hazelnuts with impact acoustics time-frequency patterns

A new adaptive time-frequency (t-f) analysis and classification procedure is applied to impact acoustic signals for detecting hazelnuts with cracked shells and three types of damaged wheat kernels. Kernels were dropped onto a steel plate, and the resulting impact acoustic signals were recorded with a PC-based data acquisition system. These signals were segmented with a flexible local discriminant bases (F-LDB) procedure in the time-frequency plane to extract discriminative patterns between damaged and undamaged food kernels. The F-LDB procedure requires no prior knowledge of the relevant time or frequency indices of the impact acoustics signals for classification. The method automatically finds all crucial time-frequency indices from the training data by combining local cosine packet analysis and a frequency axis clustering approach, which supports individual time and frequency band adaptation. Discriminant features are extracted from the adaptively segmented acoustic signal, sorted according to a Fisher class separability criterion, post-processed by principal component analysis, and fed to a linear discriminant classifier. Experimental results establish the superior performance of the proposed approach when compared to prior techniques reported in the literature or used in the field. The new approach separated damaged wheat kernels (IDK, pupal, and scab) from undamaged wheat kernels with 96%, 82%, and 94% accuracy, respectively. It also separated cracked-shell hazelnuts from those with undamaged shells with 97.1% accuracy. The adaptation capability of the algorithm to the time-frequency patterns of signals makes it a universal method for food kernel inspection that can resist the impact acoustic variability between different kernel and damage types. 2008 American Society of Agricultural and Biological Engineers