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The study introduces a theoretical analysis and numerical solution for the combustion of a hydrocarbon fuel droplet inside the combustion chamber. The study employs two mathematical models to analyze the combustion process. Conventional (Classical) model and Transient model. The combustion process of a stagnant droplet in the steady state was analyzed in the classical model, while, In the transient model, it was assumed that there is a period of time in the stages of the droplet combustion in which the droplet is heated before combustion. The effect of change in temperature on the thermo-physical properties of the fuel was adopted through the two models. For the classical model, a convenient approximation was adopted for the heat transferred inside the droplet.

Background: Coronary computed tomographic angiography (CCTA) is preferable to invasive coronary angiography (ICA) for coronary artery disease (CAD) diagnosis in elective patients without known CAD. Methods: We conducted a nonrandomized interventional study involving 2 tertiary care centres in Ontario. From July 2018 to February 2020, outpatients referred for elective ICA were identified through a centralized triage process and were recommended to undergo CCTA first instead of ICA. Patients with borderline or obstructive CAD on CCTA were recommended to undergo subsequent ICA. Intervention acceptability, fidelity, and effectiveness were assessed. Results: A total of 226 patients were screened, with 186 confirmed to be eligible, of whom 166 had patient and physician approval to proceed with CCTA (89% acceptability). Among consenting patients, 156 (94%) underwent CCTA first; 43 (28%) had borderline/obstructive CAD on CCTA, and only 1 with normal/nonobstructive CAD on CCTA was referred for subsequent ICA against protocol (99% fidelity). Overall, 119 of 156 CCTA-first patients did not have ICA within the following 90 days (i.e., 76% potentially avoided ICA, due to the intervention). Among the 36 who underwent ICA post-CCTA per protocol, 24 had obstructive CAD (66.7% diagnostic yield). If all patients who were referred for and underwent ICA at either centre between July 2016 and February 2020 (n = 694 pre-implementation; n = 333 post-implementation) had had CCTA first, an additional 42 patients per 100 would have had an obstructive CAD finding on their ICA (95% confidence interval = 26-59). Conclusion: A centralized triage process, in which elective outpatients referred for ICA are instead referred for CCTA first, appears to be acceptable and effective in diagnosing obstructive CAD and improving efficiencies in our healthcare system. Résumé: Contexte: La coronarographie par tomodensitométrie (coro-TDM) est préférable à la coronarographie invasive chez les patients sans coronaropathie connue chez qui le diagnostic d’une coronaropathie n’est pas urgent. Méthodologie: Nous avons réalisé une étude interventionnelle non randomisée dans deux centres de soins tertiaires en Ontario. Les patients ambulatoires pour qui une coronarographie invasive non urgente a été demandée entre juillet 2018 et février 2020 ont été recensés par un processus centralisé de triage et se sont fait recommander de subir d'abord une coro-TDM. Les patients qui présentaient une co-ronaropathie obstructive ou dont les résultats se trouvaient tout juste à la limite de ce diagnostic lors de la coro-TDM se faisaient recommander une coronarographie invasive subséquente. L’acceptabilité de l’intervention, sa fidélité et son efficacité ont été évaluées. Résultats: Au total, 226 patients ont été sélectionnés et 186 ont été jugés admissibles. Parmi ces derniers, 166 ont accepté de subir la coro-TDM recommandée par le médecin (acceptabilité de 89 %). Parmi les patients ayant donné leur consentement, 156 (94 %) se sont d’abord soumis à une coro-TDM, et 43 (28 %) présentaient une coronaropathie obstructive ou des résultats limites selon cet examen. Seulement un patient ne présentant pas de coronaropathie ou présentant une coronaropathie non obstructive à la coro-TDM a été orienté vers une coronarographie invasive subséquente, contrairement au protocole (fidélité de 99 %). En tout, 119 des 156 patients s’étant d’abord soumis à une coro-TDM n’ont pas eu à subir une coronarographie invasive dans les 90 jours suivants (76 % d’entre eux ont potentiellement évité une coronarographie invasive grâce à cette première intervention). Parmi les 36 patients qui ont subi une coronarographie invasive après la coro-TDM, comme le recommandait le protocole, 24 présentaient une coronaropathie obstructive (rendement diagnostique de 66,7 %). Si tous les patients qui ont été orientés vers une coronarographie invasive et qui se sont soumis à cet examen dans l’un ou l’autre des centres entre juillet 2016 et février 2020 (n = 694 avant l’instauration; n = 333 après l’instauration) avaient d’abord passé une coro-TDM, une coronaropathie obstructive aurait été décelée lors de la coronarographie invasive chez 42 patients de plus par tranche de 100 patients (intervalle de confiance à 95 % : 26 à 59). Conclusion: Le recours à un processus de triage centralisé permettant de faire d'abord passer une coro-TDM aux patients ambulatoires dans une situation non urgente qui doivent subir une coronarographie invasive semble être un moyen acceptable et efficace de diagnostiquer la coronaropathie obstructive et d’améliorer l’efficacité dans notre système de santé.

Objective: COVID-19 pandemic has greatly impacted several aspects of undergraduate students’ lives including significant effect on mental wellbeing, physical activity and eating habits which might increase the risk for developing eating disorders as these disorders tend to emerge at university age. This study aimed to assess the prevalence of eating disorders and their associated factors among undergraduate students. Materials and Methods: A cross sectional study was conducted among 624 undergraduate students from three different universities in Malaysia. Eating disorders was assessed using the Malay version of the Eating Disorder Examination Questionnaire (EDE-Q) while the emotional disturbances was assessed by the Malay version of Kessler Psychological Distress Scale (K10) and perceived social support was assessed by the revised Malay version of The 8-item Multidimensional Scale of Perceived Social Support (MSPSS). Results: The prevalence of eating disorders among students was 14.9%. There were significant differences in terms of gender and other socio-demographic factors. Eating disorders were significantly associated and positively correlated with emotional disturbances level r = 0.37. While inverse correlation between social support and eating disorders was also shown r= -0.13. Multiple linear regression analysis showed that emotional disturbances level (β = 0.212, P = 0.000) and poor social support (β = -0.126, P = 0.002) were a significantly important risk factor. Conclusion: Eating disorders are prevalent among undergraduate students, female students, emotional disturbances and high BMI are significantly associated factors. Emotional disturbances and poor social support are predictive factor for eating disorders.

This article aims to find the implementation of religious moderation and the formation of student tasamuh attitudes at MAS Al Huda, Pangkalan Susu district. This research is qualitative, collecting data through observation, interviews, and documentation studies. Primary data sources in this study include; principals, teachers of Akidah Akhlak, School Public Relations, and PKS 3 for Student Affairs and Students. The next step of data analysis is collecting data, reducing data, presenting data, and concluding data. The results of the study revealed that planning was carried out during the preparation of the syllabus and included matters relating to religious moderation in the material of Akidah akhlak. While implementing learning, the teacher uses learning methods that follow the material, such as the lecture method, and even prioritizes group discussions to instill a moderate attitude in students, namely mutual respect, respect, being fair to group friends, and being sporty during the learning process. The implication is that it has an impact on the attitudes that are built in students, such as students having better religious attitudes and social attitudes, such as being obedient to worship, respecting others, establishing intimacy, having social care, having a nationalist spirit, being tolerant, and obeying the rules.

Background: Students mental health is a common concern as it is reflected on their academic performance and quality of life. Self-esteem and family relationships play important roles in mental health. Therefore, this study is aimed to measure the prevalence of mental well-being among medical students and its associated factors including self-esteem and family relationships. Methods: A cross-sectional study was conducted among 227 undergraduate medical students from International Islamic University Malaysia (IIUM) Kuantan campus. Self-administered online questionnaires were given to the respondents. Self-esteem was assessed using the Rosenberg Self- esteem Scale questionnaire. Family relationships was divided into 2 factors; Closeness with family which was measured by 3 items adopted from the Family Adaptation and Cohesion Evaluation Scale and the second factor of family congruence was measured by 7 items from Intergenerational Family Congruence Child Scale (IFC-CS). Mental well-being was assessed using The Warwick-Edinburgh Mental Well-Being Scale. Results: The mean level of mental well-being was 50.31 + 8.83 with 15% of our respondents having low mental well- being, 70.8% having moderate mental well- being and 14.2% having high mental well- being. Pearson’s correlation analysis showed that there is a significant relationship between mental well- being and closeness to family (p0.01), family congruence (p0.01) and self-esteem (p0.01). This study found out that 38.9% of students had high self-esteem, 22.6% moderate self-esteem and 38.5% low self-esteem. No significant relationship was found between mental well-being and age, gender, year of study, main financial support, and marital status. Conclusion: Although most of the students have moderate mental well-being, however, mental health is still a vital issue. High self-esteem, family closeness and family congruence are positively correlated with high level of mental well-being among medical students. Measures need to be taken to come up with a dynamic plan to upgrade student’s self-esteem and mental well-being which in return will enhance students’ academic achievements. One of the limitations of this study is that the study design was cross sectional and so the variable’s causality and its outcome cannot be clearly assessed despite the effort to study the associations between the variables. Large scale research that involves larger and various target populations needs to be carried out to allow the evaluation of many other factors that affect well-being.

As the COVID-19 pandemic devastates globally, the use of chest X-ray (CXR) imaging as a complimentary screening strategy to RT-PCR testing continues to grow given its routine clinical use for respiratory complaint. As part of the COVID-Net open source initiative, we introduce COVID-Net CXR-2, an enhanced deep convolutional neural network design for COVID-19 detection from CXR images built using a greater quantity and diversity of patients than the original COVID-Net. We also introduce a new benchmark dataset composed of 19,203 CXR images from a multinational cohort of 16,656 patients from at least 51 countries, making it the largest, most diverse COVID-19 CXR dataset in open access form. The COVID-Net CXR-2 network achieves sensitivity and positive predictive value of 95.5 and 97.0%, respectively, and was audited in a transparent and responsible manner. Explainability-driven performance validation was used during auditing to gain deeper insights in its decision-making behavior and to ensure clinically relevant factors are leveraged for improving trust in its usage. Radiologist validation was also conducted, where select cases were reviewed and reported on by two board-certified radiologists with over 10 and 19 years of experience, respectively, and showed that the critical factors leveraged by COVID-Net CXR-2 are consistent with radiologist interpretations.

Tuberculosis (TB) remains a global health problem, and is the leading cause of death from an infectious disease. A crucial step in the treatment of tuberculosis is screening high risk populations and the early detection of the disease, with chest x-ray (CXR) imaging being the most widely-used imaging modality. As such, there has been significant recent interest in artificial intelligence-based TB screening solutions for use in resource-limited scenarios where there is a lack of trained healthcare workers with expertise in CXR interpretation. Motivated by this pressing need and the recent recommendation by the World Health Organization (WHO) for the use of computer-aided diagnosis of TB in place of a human reader, we introduce TB-Net, a self-attention deep convolutional neural network tailored for TB case screening. We used CXR data from a multi-national patient cohort to train and test our models. A machine-driven design exploration approach leveraging generative synthesis was used to build a highly customized deep neural network architecture with attention condensers. We conducted an explainability-driven performance validation process to validate TB-Net's decision-making behavior. Experiments on CXR data from a multi-national patient cohort showed that the proposed TB-Net is able to achieve accuracy/sensitivity/specificity of 99.86/100.0/99.71%. Radiologist validation was conducted on select cases by two board-certified radiologists with over 10 and 19 years of experience, respectively, and showed consistency between radiologist interpretation and critical factors leveraged by TB-Net for TB case detection for the case where radiologists identified anomalies. The proposed TB-Net not only achieves high tuberculosis case detection performance in terms of sensitivity and specificity, but also leverages clinically relevant critical factors in its decision making process. While not a production-ready solution, we hope that the open-source release of TB-Net as part of the COVID-Net initiative will support researchers, clinicians, and citizen data scientists in advancing this field in the fight against this global public health crisis.

The COVID-19 pandemic continues to rage on, with multiple waves causing substantial harm to health and economies around the world. Motivated by the use of computed tomography (CT) imaging at clinical institutes around the world as an effective complementary screening method to RT-PCR testing, we introduced COVID-Net CT, a deep neural network tailored for detection of COVID-19 cases from chest CT images, along with a large curated benchmark dataset comprising 1,489 patient cases as part of the open-source COVID-Net initiative. However, one potential limiting factor is restricted data quantity and diversity given the single nation patient cohort used in the study. To address this limitation, in this study we introduce enhanced deep neural networks for COVID-19 detection from chest CT images which are trained using a large, diverse, multinational patient cohort. We accomplish this through the introduction of two new CT benchmark datasets, the largest of which comprises a multinational cohort of 4,501 patients from at least 16 countries. To the best of our knowledge, this represents the largest, most diverse multinational cohort for COVID-19 CT images in open-access form. Additionally, we introduce a novel lightweight neural network architecture called COVID-Net CT S, which is significantly smaller and faster than the previously introduced COVID-Net CT architecture. We leverage explainability to investigate the decision-making behavior of the trained models and ensure that decisions are based on relevant indicators, with the results for select cases reviewed and reported on by two board-certified radiologists with over 10 and 30 years of experience, respectively. The best-performing deep neural network in this study achieved accuracy, COVID-19 sensitivity, positive predictive value, specificity, and negative predictive value of 99.0%/99.1%/98.0%/99.4%/99.7%, respectively. Moreover, explainability-driven performance validation shows consistency with radiologist interpretation by leveraging correct, clinically relevant critical factors. The results are promising and suggest the strong potential of deep neural networks as an effective tool for computer-aided COVID-19 assessment. While not a production-ready solution, we hope the open-source, open-access release of COVID-Net CT-2 and the associated benchmark datasets will continue to enable researchers, clinicians, and citizen data scientists alike to build upon them.

Medical image analysis continues to hold interesting challenges given the subtle characteristics of certain diseases and the significant overlap in appearance between diseases. In this study, we explore the concept of self-attention for tackling such subtleties in and between diseases. To this end, we introduce, a multi-scale encoder-decoder self-attention (MEDUSA) mechanism tailored for medical image analysis. While self-attention deep convolutional neural network architectures in existing literature center around the notion of multiple isolated lightweight attention mechanisms with limited individual capacities being incorporated at different points in the network architecture, MEDUSA takes a significant departure from this notion by possessing a single, unified self-attention mechanism with significantly higher capacity with multiple attention heads feeding into different scales in the network architecture. To the best of the authors' knowledge, this is the first “single body, multi-scale heads” realization of self-attention and enables explicit global context among selective attention at different levels of representational abstractions while still enabling differing local attention context at individual levels of abstractions. With MEDUSA, we obtain state-of-the-art performance on multiple challenging medical image analysis benchmarks including COVIDx, Radiological Society of North America (RSNA) RICORD, and RSNA Pneumonia Challenge when compared to previous work. Our MEDUSA model is publicly available.

This paper investigates the bildungsroman phenomenon as depicted in Jane Austen’s Emma (1817) by consulting Erik Erikson’s theory of psychosocial development as a framework of analysis. The most two conflicting readings in this regard could be best seen in Buckley’s (1974) claim which excluded Emma from the bildungsroman, for the genre has always been associated with the protagonist’s physical quest seeking maturity and social integration. However, Kohn (1995) read Emma as a domestic bildungsroman when he argued that Emma did not have to travel physical distances to achieve her maturity. For Kohn, Emma matured within her social sphere. This paper particularly traced Emma’s psychological and social development since this type of development is the basic ingredient of any bildungsroman novel. This paper argued that Emma cannot be read as bildungsroman not because the protagonist did set on a quest, as Buckley claimed, but mainly because Emma did not develop a sense of psychological or social maturation. After placing Emma in Erikson’s developmental stages, the study revealed that she did not really mature neither she realized her own identity. This paper proposed that Emma should not be classified as bildungsroman because the heroine distorted the real meaning of maturity and social integrity.

Background/Objective: It is important to predict the COVID-19 patient's prognosis, particularly in countries with lack or deficiency of medical resource for patient's triage management. Currently, WHO guideline suggests using chest imaging in addition to clinicolaboratory evaluation to decide on triage between home-discharge versus hospitalization. We designed our study to validate this recommendation to guide clinicians. This study providing some suggestions to guide clinicians for better decision making in 2020. Methods: In this retrospective study, patients with RT-PCR confirmed COVID-19 (N = 213) were divided in different clinical and management scenarios: home-discharge, ward hospitalization and ICU admission. We reviewed the patient's initial chest CT if available. We evaluated quantitative and qualitative characteristics of CT as well as relevant available clinicolaboratory data. Chi-square, One-Way ANOVA and Paired t-test were used for analysis. Results: The finding showed that most patients with mixed patterns, pleural effusion, 5 lobes involved, total score ≥10, SpO2% ≤ 90, ESR (mm/h) ≥ 60 and WBC (103/μL) ≥ 8000 were hospitalized. Most patients with Ground-glass opacities only, ≤3 lobes involvement, peripheral distribution, SpO2% ≥ 95, ESR (mm/h)

This study aims to investigate the similarities and differences between prospective mathematics teachers’ creative thinking skills in paper-pencil test and on a Geogebra-supported environment in terms of problem-posing. This case study used purposive sampling method for determining the participants. Findings revealed that the activities carried out in the GeoGebra-supported environment were insufficient to produce creative problems, and GeoGebra’s main utility to prospective teachers was in identifying their mistakes related to mathematical concepts and discrepancies among numerical values of the problems posed. The reasons for the low achievement in posing problem were discussed: These were; (i) lack of problem-posing experience, (ii) the structure of problem-posing activity, and (iii) prospective teachers’ mathematical content knowledge.

Background: In the present study, we aimed to evaluate the factors that might be caused by adequate anticoagulation control in patients treated with warfarin for any reason. Methods: The WARFARIN-TR (The Awareness, Efficacy, Safety, and Time in Therapeutic Range of Warfarin in Turkish Population) study included 4987 patients using warfarin between January 1, 2014 and December 31, 2014. Time in therapeutic range (TTR) was calculated according to F. R. Roosendaal's algorithm with linear interpolation. The study population divided into two groups; adequate international normalized ratio (INR) control when TTR ≥70% (Group 1, n = 1068, 21.4%) and inadequate INR control when TTR

The world is still struggling in controlling and containing the spread of the COVID-19 pandemic caused by the SARS-CoV-2 virus. The medical conditions associated with SARS-CoV-2 infections have resulted in a surge in the number of patients at clinics and hospitals, leading to a significantly increased strain on healthcare resources. As such, an important part of managing and handling patients with SARS-CoV-2 infections within the clinical workflow is severity assessment, which is often conducted with the use of chest X-ray (CXR) images. In this work, we introduce COVID-Net CXR-S, a convolutional neural network for predicting the airspace severity of a SARS-CoV-2 positive patient based on a CXR image of the patient’s chest. More specifically, we leveraged transfer learning to transfer representational knowledge gained from over 16,000 CXR images from a multinational cohort of over 15,000 SARS-CoV-2 positive and negative patient cases into a custom network architecture for severity assessment. Experimental results using the RSNA RICORD dataset showed that the proposed COVID-Net CXR-S has potential to be a powerful tool for computer-aided severity assessment of CXR images of COVID-19 positive patients. Furthermore, radiologist validation on select cases by two board-certified radiologists with over 10 and 19 years of experience, respectively, showed consistency between radiologist interpretation and critical factors leveraged by COVID-Net CXR-S for severity assessment. While not a production-ready solution, the ultimate goal for the open source release of COVID-Net CXR-S is to act as a catalyst for clinical scientists, machine learning researchers, as well as citizen scientists to develop innovative new clinical decision support solutions for helping clinicians around the world manage the continuing pandemic.

Background: Adolescence is a critical transition phase in the life of an individual to be independent and to mould their own identity. Family dynamic is the most influential factor in adolescent mental health. Objectives. This research aimed to analyse the differences of family values, psychological distress and its associated finadolescents living in a long-term residential care as compared to adolescents in an ordinary school.Method: A cross-sectional study was carried out with 150 respondents using clustered random sampling. The Asian Family Characteristics Scale was used to assess the family values. The Depression, Anxiety and Stress Scale was used to measure the mental state of the respondents.Results: Children in long-term residential care showed significantly lower family values in all domains and higher in levels of stress, anxiety, depression. Findings show that there is significant association between psychological distress and family values.Conclusion: Family dynamic has a strong ramification to behavioural and psychological aspects of adolescents. Preventive measures and policy maker should be advocated in order to minimize psychological problems among adolescence in this country.

Throughout the history, different schools including both descriptive and non-descriptive ones, have been concerned with revealing relationship between happiness and virtue. As the First and Second teachers, Aristotle and Al-Fārābī can be named as having very important roles in this sense. So, the main tenet of ethics for these two philosophers is happiness, which is mostly derived from virtue. Considering theories of these two philosophers, it became evident that Aristotle had significant effects on Islamic thinkers. In other words, they claim they have been strongly influenced by Aristotle’s ideas. An obvious example for this can be ‘Nicomachean Ethics’ which attracted the attention of both western and eastern thinkers. As the greatest and the most salient commentator, Al-Fārābī could elaborate on Aristotle’s ideas on ethics and so suggest a comprehensive theory of ultimate happiness and Utopia' ('al-madīnat al-fāḍilah'). On the other hand, following Aristotle, Al-Fārābī divided ethics into two theoretical and practical branches. Hence, basis of ethical theories introduced by the two of these philosophers is based on happiness; However, Al-Fārābī added notions of Islam and mysticism to happiness. The most straightforward definition that Aristotle offers for happiness concerns an ultimate goal which humans are eagerly seeking to acquire it. He considers the best life as a happy life which can be reached by reasoning about humans’ actions and reactions and through adopting a viewpoint. In this sense, Aristotle introduced three types of lives, namely life with pleasure, political life, and life with intellect; he knows the third type of life better and more sublime than the other two. In his book on ethics, Aristotle defined happiness as soul’s performance according to perfect virtue. Regarding soul, Aristotle divided virtues into moral and rational ones. He believed that virtue is inasmuch as its genus is a hexis (habit) and regarding to its species is a middle term. All in all, he believed in doctrine of virtue as being a “golden mean” between the extremes of excess and deficiency. Concerning the relationship between happiness and virtue, he believed that these two elements are neither dependent on nor independent of one another. Therefore, to distinguish between these two ends, attention must be paid to rules and goals: happiness is according to goals and virtue is according to rules .He contended that virtue does not guarantee happiness and that happiness requires something more than virtue. As the founder of Islamic philosophy, Al-Fārābī’s definition of happiness is similar to that introduced by Aristotle. That is, he knows happiness as the perfection that appeals to all humans and every in some ways attempt to reach it. In civil science whose aim is to define happiness, Al-Fārābī divides happiness into two categories: true happiness which is gained because of its essence and speculative happiness which is delusive one. The latter can be also named as common shares such as wealth, knowledge, etc. What Al-Fārābī speaks of virtue is mostly like what Greek people conceived of ‘Arête’. He named virtue as a thing with inherent goodness and as a fundamental concept of achieving happiness. He classifies virtues into four classes of theoretical virtues, intentional virtues, moral virtues, and practical arts. Following Plato, Al-Fārābī deems of 'virtuous city' ('al-madīnat al-fāḍilah') as a healthy complete body whose parts would function well. In this view, 'virtuous city' ('al-madīnat al-fāḍilah') is a society where its members know happiness, cooperate to achieve it and ultimate destiny of all members is interweaved. For exemplifying the relationship between happiness and virtue, he presents the allegory of soul and body. In his viewpoint, both happiness and virtue imply perfection in a way that humans can achieve the second perfection (happiness) through acquiring the first perfection (virtue); this type of happiness include humans’ ultimate sublimity and great happiness. Therefore, considering those two as the goals, Al-Fārābī knew these two elements as being dependent on one another and no separate from one another. Moreover, he expressed that happiness is in a higher rank than virtue.

Background: Using the internet excessively by students is known to cause internet addiction (IA) which may result in negative consequences such as decline in academic performance, social isolation, and emotional disturbances. This study aims to assess IA and its association with emotional disturbances among medical students. Methods: A sample of 268 medical students participated in this study. Internet addiction was assessed using Malay version of Chen Internet addiction Scale while the prevalence and severity of depression, anxiety and stress were assessed by Depression Anxiety, Stress Scale (DASS-21). Results: The rate of IA among students was 22.8%. No significant differences in terms of gender and other socio-demographic factors. IA was significantly associated and positively correlated with depression and anxiety symptoms but has inverse correlation with social interaction. Multiple linear regression analysis showed that stress (β = 0.261, P = 0.005) was a significantly important risk factor. Conclusions: IA is potentially high among medical students. Male and female students are equally affected. IA is significantly higher among students with poor social interaction. IA has a positive correlation with depression, anxiety and stress symptoms but inverse correlation with social interaction and stress can be considered as a predictive factor for IA.

FUNDAMENTO: Os peptídeos natriuréticos são liberados pelo coração em resposta ao estresse da parede. OBJETIVO: As concentrações de NT-Pro-BNP em pacientes com Fluxo Lento Coronariano (FLC) foram avaliadas antes e depois do teste de exercício e comparados com os valores dos controles saudáveis. MÉTODOS: A população do estudo foi de 34 pacientes com FLC [22 homens (64,7%), com idade 51,0 ± 6,2 anos], e 34 indivíduos normais com artérias coronarianas normais [21 homens (61,8%), com idade 53,2 ± 6,6 anos]. As taxas de fluxo coronariano dos pacientes e controles foram determinadas pelo escore TIMI Trombólise no Infarto do Miocárdio (Thrombolysis in Myocardial Infarction). As amostras de sangue foram coletadas em repouso e após o teste ergométrico. RESULTADOS: As concentrações basais de NT-Pro-BNP nos pacientes com FLC foram superiores às dos indivíduos-controle (NT-Pro-BNP: 49,7 ± 14,2 pg/mL vs. 25,3 ± 4,6 pg/mL p BACKGROUND: Natriuretic peptides are released by the heart in response to wall stress. OBJECTIVE: The NT-Pro-BNP concentrations in slow coronary flow (SCF) patients were assessed before and after the exercise test and compared with the values of healthy controls. METHODS: The study population was 34 patients with SCF [22 males (64.7%), aged 51.0±6.2 years], and 34 normal subjects with normal coronary arteries [21 males (61.8%), aged 53.2±6.6 years]. Coronary flow rates of all patients and control subjects were documented as Thrombolysis in Myocardial Infarction (TIMI) frame count. Blood samples were drawn at rest and after the exercise testing. RESULTS: The baseline NT-Pro-BNP concentrations of the SCF patients were higher than those of the control subjects (NT-Pro-BNP: 49.7±14.2 pg/mL vs. 25.3±4.6 pg/mL p

The study introduces a theoretical analysis and numerical solution for the combustionof two kinds of hydrocarbon fuel droplet inside the combustion chamber. The study employsthree mathematical models to analyze the combustion process, conventional (classical) model,transient model, and moving droplet model. The combustion process of a stagnant droplet inthe steady state was analyzed in the classical model, while, in the transient model, it wasassumed that there is a period of time in the stages of the droplet combustion in which thedroplet is heated before combustion, For the moving droplet model, the film boundaryapproximation was incorporated to express the effects of the relative motion on the combustionprocess parameters. The effect of change in temperature on the thermo-physical properties ofthe fuel was adopted through the three models. For the classical and moving droplet models, aconvenient approximation was adopted for the heat transferred inside the droplet.Computer programs were created to evaluate the required properties, solving theordinary differential equations evaluated from heat and mass transfer balances, and thenconstruct systems of non-linear equations.The three models show that thermo physical properties are strong functions toreference temperature. The transient model shows that the period of droplet heat up is mosteffective. For the moving droplet combustion model it was shown that the relative movementbetween droplet and ambient surrounding gas enhanced the mass burning rate and reduced thedroplet lifetime. The film theory approach was adopted in moving droplet model.

Background: Multi-detector computed tomography (MDCT) is the preferred modality for follow-up of paediatric neurosurgery patients. Serial imaging, however, has the disadvantage of an ionising radiation burden, which may be mitigated using the ‘as low as reasonably achievable’ (ALARA) principle. Objectives: The primary objectives were to determine the radiation dose exposure in paediatric patients subjected to MDCT imaging following neurosurgery and to compare these values with references in current literature. Our secondary objective was to assess the relationship between radiation dose and clinical scenario.Method: Retrospective descriptive data were collected from all paediatric postsurgical patients (n = 169) between the ages of 0 and 12 years who had their first followed-up scan in the year 2010 and were followed up for six months or less. Dose-length product (DLP) and current-time product were collected from the picture archiving and communication system. Demographic data including radiology reports were collected from the hospital information system. The effective doses (ED) were calculated from the corresponding DLP using age-adjusted conversion factors. For purposes of comparison with other studies, median dosimetric values were calculated and the children were grouped into three age ranges, namely younger than 3 years, 3–7 years and 8–12 years old.Results: The highest median radiation doses were noted in patients being followed-up for intracranial abscesses (1183 mGy cm) in the 8–12 year age group, most of whom were female. The lowest radiation doses were for intracranial shunt follow-ups (447 mGy cm). Median values for DLP, ED and current-time product (mAs) were comparable to reference doses in all three age groups. However, our study showed a much broader distribution of values with higher upper limits relative to reference values. Indications for follow-up included shunts (n = 110; 65%), intracranial abscess (n = 31; 18%), subdural haematoma (n = 13; 8%) and tumour (n = 6; 4%). Head trauma only accounted for 5% of the cases.Conclusion: The median radiation doses measured were comparable to values in literature and therefore deemed acceptable. The wider dose distributions of all three dosimetric parameters (DLP, ED and mAs) were attributed to inappropriate use of scan length and reference effective mAs. Adherence to recommended scan length protocols should be encouraged. Evaluation of the current use of reference effective mAs is needed and will require a separate study to determine the smallest value that can be used without compromising image quality. Further dose reductions could be achieved by omission of unenhanced scans in the follow-up of intracranial abscesses. It is recommended that diagnostic reference levels specific to South African clinical scenarios be developed to make local dosimetric audits more relevant.

This study aims to investigate the similarities and differences between prospective mathematics teachers' creative thinking skills in paper-pencil test and on a GeoGebra-supported environment in terms of problem-posing. This case study used purposive sampling method for determining the participants. Findings revealed that the activities carried out in the GeoGebra-supported environment were insufficient to produce creative problems, and GeoGebra's main utility to prospective teachers was in identifying their mistakes related to mathematical concepts and discrepancies among numerical values of the problems posed. The reasons for the low achievement in posing problem were discussed: These were: (1) lack of problem-posing experience; (2) the structure of problem-posing activity; and (3) prospective teachers' mathematical content knowledge.

Productivity estimating of a construction operation is an essential tool for the successful completion of the construction process. Productivity of a construction operation is defined as output of the system per unit of time. In this research Artificial Neural Networks approaches are presented. The main reason for using neural nerworks for construction productivity estimation is the requirement of performing complex mapping of environment and management factors to productivity. A generic description of the artificial neural networks model is provided, followed by summarized factors that affect ceramic labor productivity, then neural-network model are developed for Estimating ceramic walls productivity, the input data for the model based on experienced superintendents employed by a leading construction general contractor, test results show that the ANN approach can produce a sufficiently accurate estimate with a limited data-collection effort, and thus has the potential to provide an efficient tool for construction productivity estimation.

Pre-service mathematics teachers' content knowledge is an important issue. Therefore, detailed studies are needed to be conducted on mathematical topics. The study examines preservice elementary mathematics teachers' (PEMTs) special content knowledge (SCK) of integer addition and subtraction in the context of using multiple representations, explaining mathematical reasons lying behind the concepts and justifying them. The findings obtained from the written responses of 42 PEMTs reveal that preservice teachers do not have sufficient and balanced special content knowledge. This is especially more so in the case of addition and subtraction of numbers with opposite signs. The preservice teachers were observed to have more difficulty in using the number line model compared to the use of other representations. The findings offer some indicators about how PEMTs understand integer addition and subtraction through multiple representations and why more emphasis on the SCK components

FUNDAMENTO: Os peptídeos natriuréticos são liberados pelo coração em resposta ao estresse da parede. OBJETIVO: As concentrações de NT-Pro-BNP em pacientes com Fluxo Lento Coronariano (FLC) foram avaliadas antes e depois do teste de exercício e comparados com os valores dos controles saudáveis. MÉTODOS: A população do estudo foi de 34 pacientes com FLC [22 homens (64,7%), com idade 51,0 ± 6,2 anos], e 34 indivíduos normais com artérias coronarianas normais [21 homens (61,8%), com idade 53,2 ± 6,6 anos]. As taxas de fluxo coronariano dos pacientes e controles foram determinadas pelo escore TIMI Trombólise no Infarto do Miocárdio (Thrombolysis in Myocardial Infarction). As amostras de sangue foram coletadas em repouso e após o teste ergométrico. RESULTADOS: As concentrações basais de NT-Pro-BNP nos pacientes com FLC foram superiores às dos indivíduos-controle (NT-Pro-BNP: 49,7 ± 14,2 pg/mL vs. 25,3 ± 4,6 pg/mL p

Background: Empagliflozin is an SGLT2 inhibitor approved for use in patients with diabetes mellitus type 2 (DMT2) with or without other cardiovascular disease. Empagliflozin is taken once daily without rationale on the optimal timing for administration. This study aimed to determine the chronopharmacological effects of morning vs evening administration of empagliflozin (10 mg) in healthy Egyptian adults, by investigating the pharmacokinetics and pharmacodynamics parameters of empagliflozin depending on the intake time. Methods: An open label, sequential, two‐way crossover trial comprised of two periods with a washout period of 7 days. All participants received a single oral dose of empagliflozin (JARDIANCE ®; 10 mg film coated tablet) in the evening, and after a seven-day washout period, the morning. Pharmacokinetics parameters (primary endpoints: t max (h), C max (ng/ml), AUC 0-t (ng.h/ml); secondary endpoints: AUC 0 to ∞(ng.h/ml)) were assessed. Method validation was done prior to injection in LC/MS/MS and samples were processed by Liquid-Liquid extraction. The pharmacodynamic profile (UGE 0-24) was determined after method validation (glucose hexokinase method). Results: T max increased by 35% in the evening phase compared to the morning phase, while C max decreased by -6.5% in the evening dose compared to the morning dose. Additionally, AUC 0 to ∞ increased in the evening phase by 8.25% compared to the morning phase. The mean cumulative amount of glucose excreted (UGE ( 0-24)) increased by 43% in the evening dose compared to the morning dose Conclusion: Despite the difference in pharmacokinetics parameters between evening and morning doses, C max, AUC 0-t, AUC 0-∞, didn’t differ on the bioequivalence level. In addition, as UGE ( 0-24) didn’t statistically differ, thus, we can conclude that there is no statistical significance between the morning and evening doses. Trial registration: Clinal Trials.gov, ID: NCT03895229 (registered on 29 th March 2019).

Heat augmentation techniques play a vital role in the heating and cooling processes in industries, including solar collectors and many applications that utilize heat exchangers. Several studies are based on inserting fillers inside the tubes to enhance heat transfer. This investigation considered the effects of twisted tapes with large holes on a tubular heat exchanger's (HX) heat transmission, pressure drop, and thermal boosting factor. In the experimental section, counter-swirl flow generators used twisted tapes with pairs of 1.0 cm-diameter holes and changes in porosity (Rp) at 1.30% and 2.70%. In the experiments, air was utilized as a working fluid in a tube with a circular cross-section. The turbulent f low was considered, with Reynolds numbers (Re) domain from 4800 to 9500, and a boundary condition with a uniform wall heat f lux was constructed. The findings expound that when the number of holes rose, the Nusselt number (Nu), the factor of friction (f), and the thermal enhancement factor (η) all increased as well. Additionally, as the friction factor increased, the Nusselt number of the tape-equipped tube was noticeably higher. Additionally, it was discovered that the friction factor was between 70% and 94% lower than the values of the tube without tape, while the (Nu) was between 87% and 97% higher than the conventional tube values. The maximum value of η is 89%. According to the experimental results, empirical correlations for Nu, f, and η were also generated. [ABSTRACT FROM AUTHOR]