Single slit diffraction is part of many high-school physics curricula throughout the world. In this study, we aimed to investigate whether high-school physics teachers from Bosnia and Herzegovina, Serbia and North Macedonia are adequately prepared to discuss with their students about various aspects of the single slit diffraction pattern, particularly about vertical length of diffraction fringes. To that end we conducted a written survey which included 57 high-school physics teachers. Besides asking teachers about students’ difficulties in learning about single slit diffraction, we also asked them to specify their own difficulties with this topic and required them to solve a conceptual task. Almost every second teacher believed that vertical length of diffraction fringes can be increased by changing shape or width of the slit and only 1 out of 57 teachers managed to correctly answer why diffraction fringes become shorter when we move away from the central maximum. We concluded that physics teacher education programmes should be changed to develop understanding of both, horizontal and vertical aspects of the diffraction pattern. To that end it is useful to provide learning opportunities which encourage combining ray and wave model of light.

A detailed examination of the principle of operation behind the functioning of the full-self-powered humidity sensor is presented. The sensor has been realized as a structure consisting of an interdigitated capacitor with aluminum thin-film digits. In this work, the details of its fabrication and activation are described in detail. The performed XRD, FTIR, SEM, AFM, and EIS analyses, as well as noise measurements, revealed that the dominant process of electricity generation is the electrochemical reaction between the sensor’s aluminum electrodes and the water from humid air in the presence of oxygen, which was the main goal of this work. The response of the sensor to human breath is also presented as a demonstration of its possible practical application.

While the COVID-19 pandemic continues to spread globally, with relistic hope that will be solved with adequate vacination, more and more evidences are collected about the presence of psychi-atric and neurological manifestations and symptoms associated with this diseas. Neurological manifestations, are part of the COVID-19 clinical picture, but questions remain regarding the frequency and severity of centra nervous system symptoms, the mechanism of action underlying neurological symptoms, and the relationship of symptoms with the course and severity of COVID-19. The review of the so far published papers shows that although more and more papers are reporting neuro-logical and psyhiatric manifestations associated with COVID-19, many items remain unclear. The long-term psychological implications of this infectious diseases should not be ignored. In this paper, we aim to present a some of psychological consequences and neurological disorders associat-ed with the SARS-CoV-2 infection, and to emphasize the need a global action that requires close coordination and open-data sharing between hospitals, academic and public health institutions and the fast establishment of harmonised research priorities to face acut and long-term the neurological and psychological consequences.

Head and neck cancers (HNC) occur in the upper aerodigestive tract and are among the most common cancers. The etiology of HNC is complex, involving many factors, including excessive tobacco and alcohol consumption; over the last two decades, oncogenic viruses have also been recognized as an important cause of HNC. Major etiological agents of nasopharynx carcinoma and oropharyngeal carcinoma include Epstein-Barr virus (EBV) and human papillomaviruses (HPVs), both of which are able to interfere with cell cycle control. Additionally, the association of hepatitis C and hepatitis B infection was observed in oral cavity, oropharyngeal, laryngeal, and nasopharyngeal cancers. Overall prognoses depend on anatomic site, stage, and viral status. Current treatment options, including radiotherapy, chemotherapy, targeted therapies and immunotherapies, are distributed in order to improve overall patient prognosis and survival rates. However, the interplay between viral genome sequences and the health, disease, geography, and ethnicity of the host are crucial for understanding the role of viruses and for development of potential personalized treatment and prevention strategies. This review provides the most comprehensive analysis to date of a vast field, including HNC risk factors, as well as viral mechanisms of infection and their role in HNC development. Additionally, currently available treatment options investigated through clinical practice are emphasized in the paper.

The critical zone (CZ) is the region of the Earth’s surface that extends from the bottom of the weathered bedrock to the tree canopy and is important because of its ability to store water and support ecosystems. A growing number of studies use active source shallow seismic refraction to explore and define the size and structure of the CZ across landscapes. However, measurement uncertainty and model resolution at depth are generally not evaluated, which makes the identification and interpretation of CZ features inconclusive. To reliably resolve seismic velocity with depth, we implement a Transdimensional Hierarchical Bayesian (THB) framework with reversible‐jump Markov Chain Monte Carlo to generate samples from the posterior distribution of velocity structures. We also perform 2D synthetic tests to explore how well THB traveltime inversion can resolve different subsurface velocity structures. We find that THB recovers both sharp changes in velocity as well as gradual velocity increases with depth. Furthermore, we explore the velocity structure in a series of ridge‐valley systems in northern California. The posterior velocity model shows an increasing thickness of low velocity material from channels to ridgetops along a transect parallel to bedding strike, implying a deeper weathering zone below ridgetops and hillslopes than below channels. The THB method enhances the ability to reliably image CZ structure, and the model uncertainty estimates it yields provides an objective way to interpret deep CZ structure. The method can be applied across other near‐surface studies, especially in the presence of significant surface topography.

The antidiabetic drug gliclazide is partly metabolized by CYP2C19, the main enzyme involved in omeprazole metabolism. The aim of the study was to explore the interaction between omeprazole and gliclazide in relation to CYP2C19 phenotype using physiologically based pharmacokinetic (PBPK) modeling approach. Developed PBPK models were verified using in vivo pharmacokinetic profiles obtained from a clinical trial on omeprazole-gliclazide interaction in healthy volunteers, CYP2C19 normal/rapid/ultrarapid metabolizers (NM/RM/UM). In addition, the association of omeprazole cotreatment with gliclazide-induced hypoglycemia was explored in 267 patients with type 2 diabetes (T2D) from the GoDARTS cohort, Scotland. The PBPK simulations predicted 1.4–1.6-fold higher gliclazide area under the curve (AUC) after 5-day treatment with 20 mg omeprazole in all CYP2C19 phenotype groups except in poor metabolizers. The predicted gliclazide AUC increased 2.1 and 2.5-fold in intermediate metabolizers, and 2.6- and 3.8-fold in NM/RM/UM group, after simulated 20-day dosing with 40 mg omeprazole once and twice daily, respectively. The predicted results were corroborated by findings in patients with T2D which demonstrated 3.3-fold higher odds of severe gliclazide-induced hypoglycemia in NM/RM/UM patients concomitantly treated with omeprazole. Our results indicate that omeprazole may increase exposure to gliclazide and thus increase the risk of gliclazide-associated hypoglycemia in the majority of patients.

Cytokines and other immune regulatory molecules are critical players in the immune response against cancer. There is growing interest in testing the potential utility of systemic immune biomarkers to track cancer progression and to use them as predictors of effective responses to cancer therapy. The central hypothesis guiding this project is that specific immune biomarkers will serve as predictors of effective vs. ineffective immunotherapy in patients with malignant diseases. The objective of this study was to establish baseline of immune markers in patients already started treatment with immunotherapy (n=10) (T), patients starting, but not yet treated (S) with immunotherapy (n=10) and subjects without diagnosed malignant disease (W) (n=10). Blood was collected and plasma was isolated and used in the biomarker (100 markers) analysis using a protein microarray method (RayBiotech). The biomarkers in the three groups were analyzed by Principal Component Analysis, heat map with clustering, and differential expression based on p value, and Significance Analysis of Microarrays (SAM). Although 15 biomarkers were significantly different between S vs. W groups, based on SAM, only seven were found differentially expressed. Similarly, although 10 biomarkers were significantly different between T vs. W groups, based on SAM, only one biomarker was found differentially expressed. Furthermore, SAM revealed that responders (n=4) vs. stable (n=5) subgroup of patients within the T group exhibited 22 differentially expressed biomarkers. Future larger studies will be needed to evaluate whether immune markers will be able to predict effective vs. ineffective responses to immunotherapy and whether they may have therapeutic potential.

Artificial Intelligence (AI) has been drawing attention in the field of medical devices. However, due to system complexity, the variability of their architecture, as well as ethical and regulatory concerns there is an ongoing need to analyze its application and performance.This study presents a narrative commentary on the applications of artificial neural networks (ANN) and machine learning (ML) algorithms in medical devices, past, current and future perspectives of application. One research focus of this study was on identifying problems and issues related to the implementation of AI in medical devices. The commentary is based on scientific articles published in PubMed, Scopus ad ScienceDirect databases, official publications of international organizations: European Comission (EC), Food and Drug Administration (FDA), and World Health Organisation (WHO) published in 2009 - 2020 period. AI is revolutionizing healthcare, from medical applications to clinical engineering. However, before grasp-ing the full potential ethical, legal and social concerns need to be resolved and its application needs to be harmonized and regulated regarding equitable access, privacy, appropriate uses and users, liability and bias and inclusiveness.

Ibn Sina (Avicenna) is primarily known for his philosophy and medicine, but there is almost no scientific discipline in which this great man didn't leave a significant mark. This paper gives a brief overview of his contribution to medicine and psychology through which his unique scientific and religious approach to the study of the phenomena of human being can be best seen. Medical works of Ibn Sina represent a pinnacle of most important medical achievements of his time. These works contain synthesis of all Greek, Indian and Iranian medical schools, but also new breakthroughs achieved by Muslim scholars through their own experimentation and practice. Although he wrote many medical works, his most important one is El-Kanun fit-tib, which can be translated as The Canon of Medicine. It's made out of five books which systematically show everything known in the area of medicine up until that point in time. In it, Ibn Sina discusses, among other things, the structure of psychological apparatus of human being and the connection of psychological functions with the brain. He considered psychology to be very important for medicine, so in his psychological works he discusses, in great detail, the essence of human soul, consciousness, intellect and other psychological functions. He observed a man in his entirety, taking into consideration all aspects of his existence, paying special attention to spiritual knowledge and spiritual perfection, religiosity, and methods of achieving inner peace and well-being.

BACKGROUND Indoor air quality (IAQ) in classrooms affects children's health and academic perfor-mance. The aim of this pilot study was to determine IAQ in elementary schools different in their inter-nal and external characteristics, in settings of COVID-19 epidemics. METHODS IAQ parameters: fine particulate matter (PM2,5) mass concentration, CO2 concentration, tempera-ture and relative humidity were measured in parallel in four elementary schools/classrooms during October (non-heating season) and four months (including holiday in January) of heating season. IAQ parameters were measured in settings of anti-epidemic restrictions (≤13 students in classroom, frequent ventilation). RESULTS During October, except in one school, PM2,5 concentrations were below the upper recommended value (25 μg/m³), but started rising in all schools in the heating season. The highest concentrations of PM2,5 were registered in two schools with closed or shortly opened windows. CO2 concentrations were mostly in the recommended range (up to 1000ppm) except in the school with constantly closed windows and in three schools in February when concentrations were higher. Except in one, the same school, and in January, both temperature and relative humidity were out of the recommended range (24,0-27,0°C in non-heating; 20,0-24,0°C in heating season; and 45-55%), with temperature mainly above and relative humidity mainly below it in three schools. The largest deviation in temperature and relative humidity were registered in urban schools. Registered differ-ences may be explained by different internal and external characteristics. CONCLUSION Despite anti-epidemic restrictions, most of the measured IAQ parameters were out of the recom-mended values in heating season. In addition, further deterioration of IAQ could be expected if all students had been presented in the classroom. Finally, to assure a healthy school environment in heating season, further optimisation of both indoor and outdoor conditions is needed in both pandemic and non-pandemic settings.

A congenital hernia into the umbilical cord (CHUM) is often misinterpreted as a mild form of omphalocele. Herniated content in CHUM can be either the solitary intestinal loop or persistent omphalomesenteric duct (POMD) with the potential for traumatic injury in a case of inadequate examination of the umbilical cord and its clamping in the delivery room. Herein, we report a case of a male newborn with a functional bowel obstruction due to peritonitis caused by necrosis of iatrogenically clamped POMD in the CHUM. A 2-day-old full-term male infant was referred to the emergency department with a 1 day history of bilious vomiting, a gradual increase in abdominal distension, and absence of passage of meconium. The infant was born at 38 weeks’ gestation with a birthweight of 2,885 g. The baby was born following an uncomplicated pregnancy and a normal spontaneous vaginal delivery. The Apgar scores were eight at both 1 and 5 min. On physical examination, his abdomen was slightly distended by an umbilical ligation clip placed approximately 2.5 cm from the enlarged base of the umbilical cord (Fig. 1a). The stump of the umbilical cord was thickened and red. The baby was pale and dehydrated. An abdominal radiograph showed dilated small bowel loops due to small bowel obstruction (Fig. 1b). After resuscitation, a surgical exploration via a circumumbilical incision revealed a clamped POMD in the umbilical cord. The top of the POMD was crushed by the umbilical cord clamp (Fig. 1c). The POMD was resected at its base on the ileal loop. The ileal loop was closed transversely using 5-0 Vicryl by single-layer extra mucosal-interrupted sutures. The postoperative recovery was uneventful at a follow up of 8 years. Evaluation of the umbilical cord is a routine part of every newborn examination in the delivery room. Any suspected abnormal thickening of the base of the umbilical cord or any other malformations found should be further evaluated by a neonatologist or pediatric surgeon. Congenital hernia into the umbilical cord is a type of ventral abdominal wall defect in which the bowel usually herniates into the base of normally inserted umbilical cord through a patent umbilical ring. The condition results from a failure of return of intestine loops following the physiological gut herniation around 10–12 weeks of gestation. Due to similar morphologic features, characterized by coverage of eviscerated abdominal contents with a sac comprising outer amnion and inner peritoneal lining, CHUM may be easily misdiagnosed as a small omphalocele. Unlike an omphalocele, CHUM has an intact abdominal wall with adequate muscle development and a complete umbilical ring covered by a small cuff of skin about ~2.5 cm. Congenital hernia into the umbilical cord is usually not linked to chromosomal abnormalities but cases of trisomy 13 associated with CHUM have been reported in the literature. However, if missed, this condition can lead to intestinal damage by a low-placed umbilical cord clamp as it is shown in our illustrative case. Although very rare, similar complications have been reported in the literature. The prevention of inadvertent bowel injury during cord clamping at delivery is possible with increased awareness and knowledge regarding CHUM. Primary prevention includes the prenatal sonographic CHUM detection characterized by intestinal protrusion only into the base of the hernia. The most important preventive measure if the umbilical cord is broad based is the umbilical cord clamping at a safe distance from the basis (at least 5 cm from the abdominal wall). In conclusion, a careful inspection of the umbilical cord of all newborns in the delivery room is essential to identify any clinically relevant umbilical abnormality (e.g., a persistence of CHUM with POMD). This would prevent any iatrogenic gut injury during umbilical cord clamping. Although these complications are rare, they should be kept in mind when performing umbilical cord clamping.