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Many studies have investigated students' problem-posing activities. However, there has not been a strong focus on affective aspects in mathematical problem-posing. Also, students' understanding of the function concept whilst generating functions has not previously been investigated. This paper investigated students' misconceptions of the function concept through problem-posing tasks. It also delineates students' views on the problem-posing experiences in a functional context. The participants of this study were 74 female high-school students, of whom six were selected according to their performance on a problem-posing test to air their views. The findings show that problem-posing was a good approach for pinpointing students' misconceptions about function concept, some of which are presented in this paper. Students' interviews also indicate that, besides being productive and enjoyable for students, problem-posing activities helped them to develop a deeper understanding of the function concept through reflection. Indeed, exploring students' views in depth made it possible to provide a better analysis of the factors that can inform the effective use of problem-posing in mathematics education.

Purpose. As a scientific field, bioinformatics has drawn remarkable attention from various fields, such as information technology, mathematics, and modern biological sciences, in recent years. The topic models originating from the field of natural language processing have become the focus of attention with the rapid accumulation of biological datasets. Thus, this research is aimed at modeling the topic content of the bioinformatics literature presented by Iranian researchers in the Scopus Citation Database. Methodology. This research was a descriptive-exploratory study, and the studied population included 3899 papers indexed in the Scopus database, which had been indexed in this database until March 9, 2022. The topic modeling was then performed on the abstracts and titles of the papers. A combination of LDA and TF-IDF was utilized for topic modeling. Findings. The data analysis with topic modeling resulted in identifying seven main topics "Molecular Modeling," "Gene Expression," "Biomarker," "Coronavirus," "Immunoinformatics," "Cancer Bioinformatics," and "Systems Biology." Moreover, "Systems Biology" and "Coronavirus" had the largest and smallest clusters, respectively. Conclusion. The present investigation demonstrated an acceptable performance for the LDA algorithm in classifying the topics included in this field. The extracted topic clusters indicated excellent consistency and topic connection with each other. [ABSTRACT FROM AUTHOR]

Maryam Mirzakhani is the first and the only female winner of the Fields Medal since its establishment in 1936. She is arguably one of the greatest mathematicians of our generation. This biographical paper outlines her life and work. Her mathematical theorems and noteworthy accomplishments are just as impressive as her determination, imagination, and optimistic outlook on life. Mirzakhani's success came from her passion, creativity, and playful approach to mathematics. She felt the most rewarding part of mathematics was the enjoyment of understanding or discovering something. Mirzakhani's work was visual and focused on patterns and ideas rather than on numbers and algorithms. She constructed mathematics in an artistic way, and her goal was to always find truth and beauty in the world. Mirzakhani will forever be an inspiration to anyone who has studied her work and read her story.

We will refer to the paper "Convergence rates for Kaczmarz-type algorithms", published in Numerical Algorithms, 79(1)(2018), 1-17. It was observed by Dr. Mokhtar Abbasi (Department of Mathematics, University of Qom, Iran) that in the proof of Theorem 7, related to the linear convergence rate of the MREK algorithm it exists an inequality which is not always true. [ABSTRACT FROM AUTHOR]

As a culture-specific phenomenon, academic dishonesty (AD) remains an under-researched domain. The purpose of this study was to voice teachers' perceptions of: (a) the influential factors contributing to AD, (b) the consequences of AD for the quality of teacher–student relationships (TSR), and (c) the specific strategies for regulating TSR. Using a qualitative phenomenological design, we attempted to present a detailed description of teachers' lived experiences regarding the above aims. The participants (n = 26) were English language and Mathematics teachers with different personal and professional characteristics (Mage = 33.59; novice = 12, experienced = 14) working in public high schools of Iran. Data was collected through intensive semi-structured interviewing and analyzed by a five-step approach applied to phenomenology in psychological research. Data analysis revealed three general themes regarding teachers' perceptions with several components. We found that the lack of attention and intrinsic motivation were the prominent perceived factors with consequences for TSR. Also, personal talk and active supervision were the common techniques that teachers utilized with students who commit AD to manage and control the TSR quality. The results were discussed with reference to teachers' academic discipline, gender, and teaching experience. [ABSTRACT FROM AUTHOR]

Objective. Vaccinium genus plants have medicinal value, of which Vaccinium arctostaphylos (Caucasian whortleberry or Qare-Qat in the local language) is the only available species in Iran. Public tendency to use herbal remedies and natural products such as synthesized nanoparticles is increasing due to the proof of the destructive side effects of chemical drugs. Nanosilver products have been effective against more than 650 microbe types. This study was aimed at assessing the possibility of green synthesis of silver nanoparticles using Vaccinium arctostaphylos aqueous extract and at evaluating its antibacterial properties, as well. Materials and Methods. In order to synthesize silver nanoparticles, different volumes of Vaccinium arctostaphylos aqueous extract (3, 5, 10, 15, and 30 ml) were assessed with different silver nitrate solution concentrations (0.5, 1, 3, 5, and 10 mM) and different reaction time durations (1, 3, 5, 10, and 20 minutes) at room temperature using a rotary shaker with a speed of 150 rpm. Ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction analysis (XRD), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) were carried out. The antibacterial activity of the aqueous extract and the synthesized nanoparticles was evaluated, as well. Results. Silver nanoparticle formation process was confirmed with XRD analysis, transmission electron microscopy (TEM), and FTIR spectroscopy. The UV-Vis spectroscopy of silver colloidal nanoparticles showed a surface plasmon resonance peak at 443 nm under optimal conditions (3 ml aqueous extract volume, 1 mM silver nitrate solution concentration, and 3 min reaction time under sunlight exposure). The reduction of silver ions to silver nanoparticles in solution was confirmed, as well. Based on X-ray diffraction analysis, the size of silver nanoparticles was in the range of 7-16 nm. TEM images showed an even distribution of silver nanoparticles, with a spherical shape. FTIR spectroscopy demonstrated the presence of different functional groups of oxygenated compounds such as carboxyl, hydroxyl, and nitrogenous groups. The antibacterial properties of the synthesized nanoparticles were confirmed. Conclusion. The synthesized nanoparticles showed more antibacterial properties against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) than gram-negative ones (Escherichia coli and Salmonella enteritidis). [ABSTRACT FROM AUTHOR]

Self-regulation is a multidimensional construct that is positively related to academic achievement, such as successful mathematics performance. However, this relation of self-regulation and mathematics performance has mainly been investigated in Western countries with similar cultural contexts, although self-regulation is assumed to be context-sensitive. Therefore, the present study investigated the relation of self-regulation and mathematics performance across two different countries (Germany vs. Iran) in college students. The relation of self-regulation and mathematics performance was expected to be weaker in students of math-related fields, such as Engineering/Informatics, as they are assumed to need less self-regulation to solve the mathematics problems than students of less math-related fields, such as Human Sciences. In total, 122 undergraduate students (German = 60; Iranian = 62) of Human Sciences or Engineering/Informatics participated in this study. We measured self-regulation with the Brief Self-Control Scale (Tangney et al., 2004) and mathematics performance with a complex multiplication test. Results showed that self-regulation did not predict multiplication performance in German or Iranian students, in general. However, when the field of study was considered, self-regulation predicted multiplication performance in the subgroup of German and Iranian students studying Human Sciences within each country. We conclude that cultural context does not seem to play a dominant role in moderating the relation between self-regulation and math performance, however, field of study and more generally familiarity with math may be an important factor to consider in single or cross-cultural studies. [ABSTRACT FROM AUTHOR]

General cognitive and specific number abilities that underlay arithmetic performance have been heavily investigated among typically developing students; however, the inquiry has rarely been applied to students with mild intellectual disability (MID). We examined whether domain-general cognitive abilities (i.e. working memory, processing speed, and long-term memory) and specific number skills (i.e. approximate and exact numerical systems) are related to arithmetic performance in 93 students with MID (mental age of 7.1 to 8.9 years) and if these relationships are similar to the ones found in 113 typically developing students with the same mental age. The results of our regression models indicated that, in both groups, the three general cognitive abilities independently explained the variance in arithmetic performance when entered in one step; however, none of them had an independent contribution to arithmetic skill in the presence of the specific number abilities. These findings supported those of Von Aster and Shale's developmental model of mathematical cognition and reinforced the notion that specific number abilities constitute the basis for arithmetic skill, and it is possible with the support of the general cognitive abilities among both students with MID and typically developing students. [ABSTRACT FROM AUTHOR]

The learning process of constructing concepts in mathematics can be supported by visualization in graphical, numerical, and symbolic representations. However, previous research suggests that students have not fully taken advantage of the opportunities provided by these technologies. Two key factors, including mathematics conception and mathematics study approaches differentially used such technologies and consequently promote the quality of mathematics education. We hypothesized that these key factors play a key role in this shortcoming. A survey of 442 high school students from Iran was conducted to examine the hypotheses through structural equation modeling. Results confirmed that mathematics conception and mathematics study approaches were associated with students' experiences and evaluations of using supportive digital technologies in mathematics learning. Moreover, mathematics study approaches mediated the relationship between mathematics conception and students' experiences and evaluation of using these digital technologies. These findings explain how mathematics conception contributes to learning experiences when students use such digital technologies. [ABSTRACT FROM AUTHOR]

Stigma against people living with HIV (PLWH) seriously affects their quality of life. Moreover it can lead them to hide their HIV status from others, which in turn endangers public health. Many studies dealing with HIV‐related stigma focus on the consequences of this phenomenon and pay less attention to the social conditions which affect different types of HIV‐related stigma (anticipated, internalized and enacted stigma [ES]). Therefore, in this study, we tried to achieve more understanding about effective causal conditions of various types of experienced stigma. First of all, data were collected from 19 PLWH, using semi‐structured interviews from those who had visited the Counseling Center for Behavioral Diseases in Mashhad. Secondly, the data were analyzed by applying a mixture of two methods: thematic analysis and qualitative comparative analysis (Boolean Algebra). The analysis of the data reveals that a combination of informing family members about HIV status, lack of family support, and medical support lead to anticipated stigma; a combination of religious beliefs and poor self‐esteem results in internalized stigma and a combination of lack of family support, mistreatment by community, poor self‐esteem, poverty and no religious beliefs lead to ES. [ABSTRACT FROM AUTHOR]

Background: The high chances of getting latent tuberculosis infection (LTBI) among health care workers (HCWs) will an enormous problem in low and upper-middle-income countries. Method: Search strategies were done through both national and international databases include SID, Barakat knowledge network system, Irandoc, Magiran, Iranian national library, web of science, Scopus, PubMed/MEDLINE, OVID, EMBASE, the Cochrane library, and Google Scholar search engine. The Persian and the English languages were used as the filter in national and international databases, respectively. Medical Subject Headings (MeSH) terms was used to controlling comprehensive vocabulary. The search terms were conducted without time limitation till January 01, 2019. Results: The prevalence of LTBI in Iranian’s HCWs, based on the PPD test was 27.13% [CI95%: 18.64–37.7]. The highest prevalence of LTBI in Iranian’s HCWs were estimated 41.4% [CI95%: 25.4–59.5] in the north, and 33.8% [CI95%: 21.1–49.3] in the west. The lowest prevalence of LTBI was evaluated 18.2% [CI95%: 3.4–58.2] in the south of Iran. The prevalence of LTBI in Iranian’s HCWs who had work-experience more than 20 years old were estimated 20.49% [CI95%: 11–34.97]. In the PPD test, the prevalence of LTBI in Iranian’s HCWs who had received the Bacille Calmette–Guérin (BCG) was estimated 15% [CI95%: 3.6–47.73]. While, in the QFT, the prevalence of LTBI in Iranian’s HCWs in non-vaccinated was estimated 25.71% [CI95%: 13.96–42.49]. Conclusions: This meta-analysis shows the highest prevalence of LTBI in Iranian’s HCWs in the north and the west probably due to neighboring countries like Azerbaijan and Iraq, respectively. It seems that Iranian’s HCWs have not received the necessary training to prevent of TB. We also found that BCG was not able to protect Iranian’s HCWs from TB infections, completely. [ABSTRACT FROM AUTHOR]

Air temperature data retrieved from global atmospheric models may show a systematic bias with respect to measurements from weather stations. This is a common concern in local climate studies. The current study presents two methods based upon copulas and Conditional Probability (CP) to predict bias-corrected mean air temperature in a data-scarce environment: CP-I offers a single conditional probability as a predictor, CP-II is a pixel-wise version of CP-I and offers spatially varying predictors. The methods were applied on daily air temperature in the Qazvin Plain, Iran that were collected at 24 weather stations and 150 ECMWF ERA-interim grid cells from a single month (June) over 11 years. We compared the methods with the commonly applied conditional expectation and conditional median methods. Leave-k-out cross-validation and correlation scores show that the new methods reduced the bias with 44–68% for the full data set and with 34–74% on a homogeneous subarea. We conclude that the two methods are able to locally improve ECMWF air temperatures in a data-scarce area. [ABSTRACT FROM AUTHOR]

Introduction: The results of the network scale-up (NSU) method in estimating the size of key populations for HIV might be biased if the recruited subjects are not fully informed of the risky behaviors of people in their networks (low visibility), or key populations have a smaller social network (low popularity). We aimed to measure such biases in the size estimation of people who inject drugs (PWIDs), and female sex workers (FSWs) in Iran. Methods: We interviewed 163 male PWIDs, 76 FSWs (known as egos) and 600 subjects from the general population. We selected twenty first-names (ten males and ten females) and asked the study subjects separately how many people they knew with one of these names (known as alters). Visibility Factor (VF) was defined as the percentage of FSW or PWID alters that were aware of their behavior. In addition, the popularity factor (PF) was calculated by dividing the number of alters reported by FSWs and PWIDs into that of the general population. The 95% uncertainty intervals (UI) were calculated using bootstrap technique. Results: The VF was estimated at 54% (95% UI: 52%–56%) for PWID and 45% (95% UI: 42%– 48%) for FSW. The VF among the peer alters was significantly higher than non-peer ones. The PF for PWID and FSW was 69% (95% UI: 66%–73%) and 77% (95% UI: 72%–83%), respectively. The cross-validation and name splitting analysis showed that our estimates were not influenced by any single name. Conclusions: Both correction factors, particularly VF were far from one, and NSU results without correction, could lead to up to 4 times underestimation of the sizes. Therefore, applying these coefficients is necessary in NSU projects. [ABSTRACT FROM AUTHOR]