Top-N Knowledge Concept Recommendations in MOOCs Using a Neural Co-Attention Model

Massive Open Online Courses (MOOCs), which provide learners with a large-scale, open-access learning opportunity, have drawn a lot of attention recently. The amount of information available on MOOCs is increasing, making it challenging for learners to choose the best course materials and leading to low learning efficiency and high dropout rates. To address these problems, Recommendation Systems (RSs) have been researched as a direct approach of delivering educational content to learners while also attracting their interest. However, a course often consists of various learning concepts, each of which covers a different topic. Explicitly proposing courses can cause the lack of learners’ attention to a particular knowledge concept. We introduce a Top-N Knowledge Concept Recommendations in MOOCs using a Neural Co-Attention Model, called NCO-A, that integrates significant heterogeneous data with recommendations based on knowledge concepts. The NCO-A model’s effectiveness has been proven by extensive experiments on three real-world datasets

The influence of ageing on the morphological and optical properties of thin TPD films

This paper presents the influence of ageing on the morphological and optical properties of TPD (N,N-bis(3-methylphenil)-N,N- diphenylbenzidine) thin films. Understanding of the nucleation mechanism and growth dynamics of molecular thin films is pivotal for controlling their morphology and the film interfacial properties, while the influence of ageing is essential for the potential commercial utilization. Initially, thin films were prepared using a combinatorial physical vapour deposition (CPVD) method, following a cosine-like distribution profile of thickness along mono-crystal silica substrate. Morphology of thin films was investigated by using optical (OM) and atomic force microscopy (AFM). The link between optical properties and the resulting thin film morphology was made by spatially correlated morphological (AFM and OM) and optical (absorption and photoluminescence) measurements. The changes in the absorption and photoluminescence spectra are strongly connected to the ageing-induced changes in the microstructure of thin films. Regardless of morphological and differences in the film thickness (two orders of magnitude), all films show amorphous arrangement just after the deposition. Ageing of these films in regular atmosphere conditions results in morphological and changes in optical properties induced by the crystallization. The crystallization of initially amorphous samples was also confirmed by the differentional scanning calorimetry (DSC) measurements. All results indicate the limited possibility of using TPD films in organic electroluminescent devices

Risk Factors of Adverse Maternal Outcome among SARS-CoV-2 Infected Critically Ill Pregnant Women in Serbia

Background and Objectives: During the COVID-19 pandemic, Serbia has faced devastating losses related to increased mortality rates among men and women of all ages. With 14 registered cases of maternal death in 2021, it became obvious that pregnant women are faced with a serious threat that jeopardises their life as well as the life of their unborn child. Studying the consequences of the COVID-19 pandemic on maternal outcomes is vivifying and stimulating for many professionals and decision-makers, and knowing the contextual characteristics can facilitate the application of literature findings in practice. Therefore, the aim of this study was to present findings of maternal mortality in Serbia associated with SARS-CoV-2 infected and critically ill pregnant women. Methods: Clinical status and pregnancy-related features were analysed for a series of 192 critically ill pregnant women with confirmed SARS-CoV-2 infection. According to the treatment outcome, pregnant women were divided in two study groups: a group of survivors and a group of deceased patients. Results: A lethal outcome was recorded in seven cases. Pregnant women in the deceased group were presenting at admission more commonly with X-ray–confirmed pneumonia, a body temperature of >38 °C, cough, dyspnea, and fatigue. They were more likely to have a progression of the disease, to be admitted to intensive care unit, and be dependent from mechanical ventilation, as well as to have nosocomial infection, pulmonary embolism, and postpartum haemorrhage. On average, they were in their early third trimester of pregnancy, presenting more commonly with gestational hypertension and preeclampsia. Conclusions: Initial clinical manifestations of SARS-CoV-2 infection, such as dyspnea, cough, fatigue, and fever, could be a potent factors in risk stratification and outcome prediction. Prolonged hospitalization, ICU admission, and associated risk of hospital-acquired infections require strict microbiological surveillance and should be a constant reminder of rational antibiotics use. Understanding and identification of risk factors associated with poor maternal outcomes among pregnant women infected with SARS-CoV-2 should warn medical professionals of potentially unwanted outcomes and can be used for organising an individualised treatment for a pregnant patient’s specific needs, including a guide to necessary consultations with medical specialists in various fields

Genetic and Environmental Dispositions for Cardiovascular Variability: A Pilot Study

Background: The aim of our study was to evaluate the degree of genetic homozygosity in the group of patients with coronary artery disease (CAD), as well as to evaluate morphogenetic variability in CAD patients regarding the presence of investigated risk factors (RF) compared to a control sample of individuals. Additionally, we aimed to evaluate the distribution of ABO blood type frequencies between tested samples of individuals. Methods: This study analyzed individual phenotype and morphogenetic variability of 17 homozygously-recessive characteristics (HRC), by using HRC test in a sample of 148 individuals in CAD patients group and 156 individuals in the control group. The following RF were analyzed: hypertension, diabetes mellitus, hyperlipidemia, and smoking. Results: The mean value of HRC in CAD patients is significantly higher, while variability decreases compared to the control sample (CAD patients: 4.24 ± 1.59, control sample: 3.75 ± 1.69; VCAD-patients = 37.50%, VC = 45.07%). There is a significant difference in individual variations of 17 HRC between control sample and CAD patients (χ2 = 169.144; p < 0.01), which points out to different variability for tested genes. Mean values of HRC significantly differed in CAD patients in regard to the number of RF present. A blood type (OR = 1.75) is significant predictor for CAD, while O blood type (OR = 0.43) was significantly associated with controls. Conclusion: There is a higher degree of recessive homozygosity in CAD patients versus individuals in the control sample, and the presence of significant variations in the degree of recessive homozygosity as the number of tested RF increases

Influencing on optical properties of buffered TiO2-Au thin film systems by deposition and annealing parameters

One of the ways to increase efficiency of TiO2 thin films is by doping and coating with metals. Metaldoped TiO2 can reduce electron-hole recombination and increase hydroxyl radical concentration on the surface of TiO2, resulting in increase in the photocatalytic activity.Recent studies of J. Li at al.[1] and S. Y. Lee et al.[2] with Au doped TiO2 thin films showed that this systems have enhanced photocatalytic activity in comparison to pure TiO2 thin films. Also recent study[3] showed that Au doped TiO2 thin films are great candidates beside photocatalysis for enhancing visible light water splitting.TiO2 and TiO2:Au thin films were obtained by DC magnetron sputtering of Ti target with Ar ions in O2 atmosphere. In the case of doped TiO2 thin films with Au, three different systems were deposited for comparison (Fig.1). Post deposition annealing for 3h on 400 °C was carried out in nitrogen atmosphere. For structural analyses XRD, XPS, TEM and AFM methods were used, while for optical characterization UV/Vis method was used. The photo-degradation rate was measured using Rhodamine B which simulated pollutant. Analysis of the binding energy in the corresponding XPS spectra showed that deposited films have good stoichiometry of TiO2 and that concentration of Au on the surface can be controlled by sputtering and annealing conditions. Post deposition annealing caused diffusion of Au atoms through the layer as it was shown by TEM and EDS. Obtained TiO2 thin films before deposition were amorphous-like structured, and after annealing on 400 °C showed that anatase phase dominates in the structure. All Au doped TiO2 thin films showed better photo-degradation rates then pure TiO2.VIII International School and Conference on Photonics and HEMMAGINERO workshop : PHOTONICA2021 : book of abstracts; August 23-27, 2021; Belgrad

The Gender Impact on Morphogenetic Variability in Coronary Artery Disease: A Preliminary Study

We analyzed morphogenetic variability and degree of genetic homozygosity in male and female individuals with coronary artery disease (CAD) versus unaffected controls. We have tested 235 CAD patients; 109 were diagnosed also with diabetes mellitus (DM) and 126 with hypertension (HTN). We additionally evaluated 152 healthy individuals without manifested CAD. For the evaluation of the degree of recessive homozygosity, we have performed the homozygously recessive characteristics (HRC) test and tested 19 HRCs. In controls, the frequency of HRC for males was 2.88 ± 1.89, while for females, it was 3.65 ± 1.60. In the CAD group, the frequency of HRC for males was 4.21 ± 1.47, while for females, it was 4.73 ± 1.60. There is significant difference in HRC frequencies between controls and CAD separately for males (p < 0.001) and females (p < 0.001). The same applies between controls and CAD with DM (males: p < 0.001 and females: p = 0.004), and controls and CAD with HTN (males: p < 0.001 and females: p < 0.001). There is no significant difference in HRC frequencies between the group of CAD with DM and the group of CAD with HTN (males: p = 0.952 and females: p = 0.529). Our findings point to the increased degree of recessive homozygosity and decreased variability in both genders of CAD patients versus controls, indicating the potential genetic predisposition for CAD

The Association between Participation in Fights and Bullying and the Perception of School, Teachers, and Peers among School-Age Children in Serbia

Participating in physical fighting and bullying can be a cause of severe injury and death among school-age children. Research evidence can support school and health actors’ efforts to improve school-age children’s development and health capacity for life. The study aims to assess the prevalence of school-age children’s participation in fights and bullying in Serbia, and to examine the relevance of students’ socio-demographic characteristics and perceptions of school and relations with other students and professors for participation in fights and bullying. A secondary analysis is also performed on the original data of the 2017 HBSC study, which was conducted on 3267 students in a nationally representative sample of primary and high schools in Serbia. We sought to investigate the relationship between eight socio-demographic characteristics and nine school-related perceptions, with two outcome variables: taking part in fights and taking part in bullying, examined by using univariate and multivariate logistic regression. The main results show that 50.8% of boys and 17.1% of girls have taken part in fights, while 17.7% boys and 10.4% of girls have taken part in bullying. Students who felt a large and very large burden of school obligations were 1.43 times more likely to participate in bullying at least once, while they were 1.38 and 2.12 times more likely to participate in multiple fights and 4.04, 1.24, and 2.78 times more likely to participate multiple times in bullying. Multiple participation in fights and in bullying is significantly negatively associated with female gender, younger age years, good and very good perception of family financial status and quality of life, and positive perceptions of school and relations they have with other students and professors. Fights among school-age children are significantly positively associated with living with relatives/legal guardians and poor quality of life. In conclusion, the prevalence of participating in at least one fight/bullying is higher than in multiple fights/bullying. These associations suggest a necessity to enhance the monitoring and control of peer behavior among school-age children. The findings of the study imply key enablers of protection, such as building relationships based on team spirit and work, friendly behavior, empathy, and help, which should be included in the value system of school and family activities in programs to combat fights and bullying in school-age children

Impact of Right Heart Failure on Clinical Outcome of Left Ventricular Assist Devices (LVAD) Implantation: Single Center Experience

The aim of this study was to examine the incidence and significance of right heart failure (RHF) in the early and late phase of left ventricular assist device (LVAD) implantation with the identification of predictive factors for the development of RHF. This was a prospective observational analytical cohort study. The study included 92 patients who underwent LVAD implantation and for whom all necessary clinical data from the follow-up period were available, as well as unambiguous conclusions by the heart team regarding pathologies, adverse events, and complications. Of the total number of patients, 43.5% died. The median overall survival of patients after LVAD implantation was 22 months. In the entire study population, survival rates were 88.04% at one month, 80.43% at six months, 70.65% at one year, and 61.96% at two years. Preoperative RHF was present in 24 patients, 12 of whom died and 12 survived LVAD implantation. Only two survivors developed early RHF (ERHF) and two late RHF (LRHF). The most significant predictors of ERHF development are brain natriuretic peptide (BNP), pre-surgery RHF, FAC < 20%, prior renal insufficiency, and total duration of ICU stay (HR: 1.002, 0.901, 0.858, 23.554, and 1.005, respectively). RHF following LVAD implantation is an unwanted complication with a negative impact on treatment outcome. The increased risk of fatal outcome in patients with ERHF and LRHF after LVAD implantation results in a need to identify patients at risk of RHF, in order to administer the available preventive and therapeutic methods

Health Predictors of Pain in Elderly—A Serbian Population-Based Study

Objectives: The aim of our study was to evaluate the association of health factors with the presence and different degrees of pain in elderly above 65 years of life. Methods: The population-based study included 3540 individuals above 65 years of age of life from twofold stratified household sample representative for Serbia, during 2013 (the average age 73.9 &#177; 6.3 years; average Body Mass Index was 26.7 &#177; 4.4, females 56.8%, living with partner 55.5%, with primary education 55.3%, with poor wealth index 55.8% and from rural settings 46.2%). As health predictors of pain, we analyzed further health parameters: self-perceived general health, long-lasting health problems, diagnosed pulmonary disease, cardiovascular disease, musculoskeletal disease, diabetes, hyperlipidemia, hypertension and other chronic diseases. Pain domain of SF-36 version 2.0 was used for pain assessment. Results: Significant health predictors of pain were: self-perceived general health (OR 2.28), where bad perception of self-perceived general health in our study had greater risk of pain with higher degree of severity; long-lasting health problems (OR 1.60), where elderly with long-lasting health problems had almost twice the risk of moderate degree of pain, and above twice the risk for severe degree of pain; pulmonary disease (OR 1.38); musculoskeletal disease (OR 2.98) and other chronic diseases (OR 1.71). The presence of musculoskeletal disease increases the risk for pain, even more than double in severe versus mild degrees of pain. Conclusion: Bad self-perceived general health, long-lasting health problems, pulmonary, musculoskeletal diseases, cardiovascular disease and other chronic disease were significant health-related predictors of various degrees of pain in elderly

Cross-Cultural Adaptation and Validation of the Serbian Version of the ICS SF Male Questionnaire

Introduction. The objective of this study was to cross-culturally adapt and validate ICS male SF questionnaire to Serbian language. Materials and Methods. This study included 91 male patients with lower urinary tract symptoms and 24 men with similar age and with confirmed absence of LUTS. ICS male SF questionnaire was translated from English to Serbian language and then back-translated to English. Results. Internal consistency was high in both dimensions, voiding (Cronbach’s alpha = 0.916) and incontinence (Cronbach’s alpha = 0.763). Comparison of the average scores between patients and controls revealed significant differences in both dimensions: voiding (med = 8 versus med = 0; P<0.001) and incontinence (med = 3 versus med = 0; P<0.001). Interclass correlation revealed high testretest validity in both dimensions, voiding ICC = 0.992 P<0.001 and incontinece ICC = 0.989 P<0.001. Correlation analysis revealed high agreement between ICS male SF voiding dimension and IPSS questionnaire (ρ=0.943; P<0.001). Conclusion. The Serbian version of male ICS SF questionnaire showed acceptable reliability and validity. The ICS male SF questionnaire could be used in routine practice as an easy and comprehensive tool for assessment of LUTS