Abstract Objectives Restless legs syndrome (RLS) is a disease from the spectrum of movement disorders, the prevalence of which increases significantly during pregnancy and is associated with poor sleep, a drop in daytime energy, and the development of psychological disorders during pregnancy and the postpartum period. Methods The IRLSS scale was used to determine the presence of RLS symptoms. The total test sample that included the tested and control groups was (n=390) subjects. The examined group consisted of pregnant women (n=260), and the control group consisted of female students (n=130). In total, 260 pregnant women were monitored 6 months after pregnancy. Three measurements were performed, first in the third trimester of pregnancy, second two months after delivery, third 6 months after delivery, while one cross-sectional measurement was performed for the control group. Results The prevalence of RLS in pregnancy is highest in the third trimester and amounts to 26.5 %. In the postpartum period, a significant decrease in the prevalence of RLS was observed, measured two months after delivery (18.1 %). Postpartum, over time, a decrease in the prevalence of RLS was noticed, and six months after delivery it was (7.3 %), when it practically approached the prevalence of the control group (standard population) which was (6.2 %). Conclusions The prevalence of RLS is highest during the third trimester of pregnancy and decreases after delivery so that 6 months after delivery it approaches the prevalence of the standard population.

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This research explores the initial attitudes of special educators towards socially assistive robots (SAR) and considers how cultural and socioeconomic backgrounds shape these attitudes. Special educators providing services to individuals with autism spectrum disorder (ASD) in the United States and Serbia were surveyed, representing distinct cultural and socioeconomic contexts. Comparing their attitudes offers valuable insights into facilitating SAR adoption for ASD treatment across different cultural landscapes. Additionally, this study conducts a comparative analysis of cultural dimensions in the two countries to contextualize attitudes toward SAR use in ASD treatment. A nonexperimental quantitative approach was employed utilizing a cross-sectional survey design with purposive samples of special educators who provide services to individuals with ASD in the U.S. and Serbia to establish initial attitudes toward SARs. The outcomes derived from this investigation reflect the pervasive influence of the cultural contexts. Apprehension has been identified as a significant factor shaping attitudes toward SAR adoption among the Serbian cohort, while a more favorable disposition towards this technology typifies the U.S. participants. The adoption and utilization of SARs, as reported by participants in the U.S., face relatively fewer attitudinal barriers.

With the ever-increasing number of polymer materials and the current number of commercially available materials, the polymer gear design process, regarding the wear lifetime predictions, is a difficult task given that there are very limited data on wear coefficients that can be deployed to evaluate the wear behavior of polymer gears. This study focuses on the classic steel/polymer engagements that result in a wear-induced failure of polymer gears and proposes a simple methodology based on the employment of optical methods that can be used to assess the necessary wear coefficient. Polymer gear testing, performed on an open-loop test rig, along with VDI 2736 guidelines for polymer gear design, serves as a starting point for the detailed analysis of the wear process putting into service a digital microscope that leads to the evaluation of the wear coefficient. The same wear coefficient, as presented within the scope of this study, can be implemented in a rather simple wear prediction model, based on Archard’s wear formulation. The developed model is established on the iterative numerical procedure that accounts for the changes in tooth flank geometry due to wear and investigates the surface wear impact on the contact pressure distribution to completely describe the behavior of polymer gears in different stages of their lifetime. Although a simple one, the developed wear prediction model is sufficient for most engineering applications, as the model prediction and experimental data agree well with each other, and can be utilized to reduce the need to perform time-consuming testing.

This paper investigates the rate of convergence of a certain mixed monotone rational second-order difference equation with quadratic terms. More precisely we give the precise rate of convergence for all attractors of the difference equation $x_{n+1}=\frac{Ax_{n}^{2}+Ex_{n-1}}{x_{n}^{2}+f}$, where all parameters are positive and initial conditions are non-negative.The mentioned methods are illustrated in several characteristic examples. 2020 Mathematics Subject Classification. 39A10, 39A20, 65L20.

In the article, we use the subset sum formula over a finite abelian group on the product of finite groups to derive the number of restricted partitions of elements in the group and to count the number of compositions over finite abelian groups. Later, we apply the formula for the multisubset sum problem on a group $\mathbb{Z}_n$ to produce a new technique for studying restricted partitions of positive integers. 2020 Mathematics Subject Classification. 05A17, 11P81

According to Mitchelmore [1], generalisations are the cornerstone of school mathematics, covering various aspects like numerical generalisation in algebra, spatial generalisation in geometry and measurement, as well as logical generalisations in diverse contexts. The process of generalising lies at the heart of mathematical activity, serving as the fundamental method for constructing new knowledge [2, 3]. In this paper we will generalise an interesting geometry problem that appeared in the 1995 edition of the International Mathematical Olympiad (IMO) [4].

The aim of the article is to present to the medical, and then to the general public, the person and work of Milivoje Sarvan (1896–1978)—one of the pioneers of social paediatrics in Serbia and one of the most prominent paediatricians, scientists and organizers of health services in Bosnia and Herzegovina in the second half of the 20th century. Milivoje Sarvan was born in 1896 in Požega, in the Kingdom of Serbia. He completed his medical studies in Lyon (France) in 1921. Upon his return to Serbia, he was a county physician in Aleksinac for three years and, shortly after the establishment of the University Children’s Hospital in Belgrade in 1924, he was among the first assistants employed there. Out of the total of 23 years of professional work in Serbia, for 19 years he was an assistant and assistant professor at the Faculty of Medicine in Belgrade. At the end of 1946, at the initiative of the Ministry of Public Health of the People’s Republic of Bosnia and Herzegovina, Dr. Milivoje Sarvan was appointed full professor and head of the Department of Paediatrics at the newly established Faculty of Medicine in Sarajevo. At the same time, he was elected head of the Paediatric Clinic in Sarajevo when it was established, and he would later manage it from 1947 until his retirement in 1967. Already at the beginning, Prof. Sarvan developed the activities of the Clinic in several directions: he created the conditions for clinical, teaching and scientific research work. He took care of the education of future paediatricians and child care workers, organized courses in social paediatrics for general practitioners and professional training for paediatricians in the country and abroad. The next period of his activities was marked by the intensive development of the Clinic in all areas of its work. He published more than 120 professional and scientific papers in national and foreign medical journals, and several health education books on mother and child care that have been published in several editions, with large print runs. He was the dean of the Faculty of Medicine and vice-rector of the University of Sarajevo, founder of the Paediatric Section of the Society of Physicians of Bosnia and Herzegovina, lifetime president of the Association of Paediatricians of Yugoslavia, a member of the Scientific Society of Bosnia and Herzegovina from 1955 and the Academy of Sciences and Arts of Bosnia and Herzegovina from its foundation in 1966. He was honoured with high level social awards and recognitions, including the highest state award of the Socialist Federative Republic of Yugoslavia—the AVNOJ award. After his retirement (1967), he lived in Belgrade, where he died in 1978. Conclusion. Bearing all of this in mind, there is no doubt that Dr. Milivoje Sarvan is one of the significant figures in the field of professional, scientific and organizational work in the field of children’s health care in the former Yugoslavia, leaving a significant and indelible mark in the current states of Serbia and Bosnia and Herzegovina.

Tufa deposits in karst rivers are unique habitats created by mutual interactions between specific environmental and biotope features and inhabited by diatoms as a highly abundant and diverse algal group. This pilot study aimed to investigate the diversity of diatom communities on tufa depositing habitats and assess the Una River’s ecological status using a comparative molecular and morphological approach for diatom identification. The 312 base pairs of the rbcL gene were barcoded and analyzed using MiSeq reads and amplicon sequence variants (ASVs) obtained by the DADA2 pipeline. The reference database Diat.barcode v7 was used for taxonomic assignment. The morphological identification of the diatoms was carried out in parallel. In total, the combined dataset revealed 46 taxa identified at genus rank, 125 on the subgenus, and 145 on combined taxonomy rank. The metabarcoding approach mostly leads to a lower number of identified taxa at species rank (58 in molecular vs. 119 in optical inventory), resulting in higher values of beta diversity and heterogeneity in diatom assemblages in samples obtained by morphological approach. Despite the high percentage of taxonomically not assigned diatom ASVs to the species rank, high Shannon diversity index values and a similar number of taxa per locations compared to the morphological approach were obtained. Taxa Achnanthidium minutissimum (Kützing) Czarnecki, Achnanthidium pyrenaicum (Hustedt) H.Kobayasi, Amphora pediculus (Kützing) Grunow, Diatoma vulgaris Bory, Navicula cryptotenella Lange-Bertalot, and Navicula tripunctata (O.F.Müller) Bory were identified at all locations in both inventories. Although limited consistency in the diatom abundances between the two inventory datasets was found, a similar grouping of samples was observed connected to the river’s longitudinal gradient. The data obtained using molecular approach in most sites indicated a mostly lower ecological status (good or moderate) compared to the data obtained from the morphological approach (high, good, and moderate). The potential of environmental DNA (eDNA) diatom metabarcoding for water monitoring and diversity studies is undeniable, but to fully realize the benefits of these methods in the future, it is essential to standardize protocols and expand the reference database for species found in specific habitats, such as tufa deposits.