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Contribution: Although a limited number of studies have compared textbooks used in introductory science courses (ISCs) and technical engineering courses (TECs), such a study has not been conducted regarding the Laplace transform (LT). The LT is one of the important topics that electrical engineering students learn as part of their undergraduate degree. It is instrumental in both ISCs (e.g., DEs) and TECs (e.g., signal processing (SP)). Background: Textbooks stand as one of the main resources for teaching and learning mathematics. Previous research has highlighted differences in how mathematical concepts are discussed in ISCs and TECs. These disparities might hinder students' opportunities to learn mathematics and identify the importance of mathematics in engineering. Intended Outcomes: The findings have the potential to increase awareness of mathematics and engineering instructors regarding the teaching and learning of the LT in ISCs and TECs. Additionally, it could result in the identification of several suggestions for textbook authors of DEs and SP, ultimately contributing to the improvement of engineering education for (electrical) engineering students. Application Design: This study uses the praxeological analysis rooted in the Anthropological Theory of the Didactic to analyze two textbooks. One is tailored for teaching and learning DEs, while the other addresses teaching and learning SP, a mandatory course for electrical engineering students in many countries. Findings: The findings indicate that there are several differences between the two textbooks, including differences in the purpose/motivation of presenting this topic and the definitions provided for the LT.

Recent literature underlines the increasing use of online platforms in learning undergraduate mathematics, where students refer to these as supplementary resources to develop their mathematical understanding. Through an intrinsic case study, we focus on a highly viewed YouTube learning resource for learning derivative. The selected case is from "3Blue1Brown," a YouTube channel whose founder has received an award from the American Mathematical Society. The video has garnered more than 3.3 million views in the past couple of years. Reflecting on the relevant literature, a realization tree for derivative is developed and then used as an analytical tool to analyze this resource to explore what realizations have been used in it to facilitate students' understanding of derivative. The findings indicate that the analyzed YouTube resource discusses various realizations of derivative, including all its five main realizations, and effectively utilizes new digital technology for discussing these realizations. Such an exceptional resource for learning mathematics leads us to suggest that mathematics lecturers raise their awareness about such online free resources and incorporate them into their teaching packages when appropriate to facilitate student learning.

Task design is an important element of effective mathematics teaching and learning. Past research in mathematics education has investigated task design in mathematics education from different perspectives (e.g., cognitive and cultural) and offered a number of (theoretical) frameworks and sets of principles. In this study, through a narrative research in the form of autoethnography, I reflected on my past teaching and research experience and proposed a (theoretical) framework for task design in mathematics education. It contains four main principles: (a) inclusion, (b) cognitive demand, (c) affective and social aspects of learning mathematics, and (d) theoretical perspective(s) toward learning mathematics. This framework could be used as a tool for critically reflecting on current practices in terms of task design in teaching mathematics and research in mathematics education. It may also contribute to ongoing research in mathematics education about task design and enable or enhance opportunities for dialogue between lecturers, teachers, and researchers about how to design rich mathematical tasks for teaching and research purposes.

Abstract Objective Carotid artery web is a possible cause of ischemic stroke, especially in young patients who lack conventional risk factors. The immediate and long‐term outcomes are not well studied. We aimed to determine the association between an ipsilateral carotid web and in‐hospital stroke recurrence. Methods We analyzed data from adult patients admitted with an acute anterior circulation large vessel occlusion at a Comprehensive Stroke Center between July 2015 and March 2023. The primary outcome was in‐hospital stroke recurrence and secondary outcome was in‐hospital recurrent LVO. Multivariable logistic regression was performed to examine the association between ipsilateral carotid web and recurrent ischemic stroke and recurrent LVO. Results Of the 1463 patients with anterior circulation large vessel occlusion, 27 (1.8%) had an ipsilateral carotid artery web. Patients with carotid web were younger (median age (IQR), 60 years (53–67 years) versus 74 years (62–84 years), P

Combating climate change and reducing CO2 emissions are essential for achieving the Sustainable Development Goals within a sustainable development framework. Various factors, such as institutional quality, affect environmental quality, and quantifying this linkage can lead to appropriate policy-making aimed at reducing pollution. The present study provides a comprehensive analysis of the impact of institutional quality on CO2 emissions in the Middle East and North Africa (MENA) region at both the aggregate (institutional quality) and disaggregate levels (corruption control, government effectiveness, political stability, violence and terrorism, regulatory quality, rule of law, voice, and accountability). This study analyzes data from 1996 to 2018 using Driscoll-Kraay and Newey-West standard error approaches to assess the impact of various factors on environmental quality. The findings reveal that GDP, non-renewable energy consumption, and trade activities have a significant negative effect on the environment. In contrast, oil prices, renewable energy, and foreign direct investment (FDI) help reduce CO2 emissions in the long run. Institutional quality and its other five indices, except for political stability and the absence of violence/terrorism, are found to contribute to the reduction of CO2 emissions in the region. Furthermore, the Dumitrescu and Hurlin Granger non-causality model reveals bidirectional causal relationships between GDP, renewable and non-renewable energies, trade, FDI, and institutional quality with CO2 emissions. Reducing emissions in the MENA region can be achieved by promoting green economic growth, developing renewable energy and energy efficiency industries, investing in low-carbon infrastructure, and directing FDI toward sustainable projects.

This paper reports a study of university lecturers' and students' experiences of teaching and learning mathematics following the abrupt requirement to switch to online teaching in 2020. A goal of the study is to share experiences that could be useful to improve the teaching and learning of mathematics in online settings. The qualitative research described is a phenomenological study and draws on interviews with ten mathematics lecturers and six undergraduate students who were enrolled in at least one university mathematical course during the lockdown in 2020. The interview data were analysed using a thematic approach. This paper reports findings regarding perceptions of lecturers and students about the challenges and benefits of online teaching and learning of mathematics, how the transition to online education has influenced assessment and sharing useful approaches for teaching and learning mathematics in online settings.

Sustainable management of water, energy, and food (WEF) under climate change will be a significant challenge for arid agricultural systems. This study developed a fractional non-linear multi-objective programming (FNLMOP) model to optimize resource allocation and improve agricultural sustainability in these systems under climate change. The model was designed in the framework of the WEF nexus to simultaneously improved energy productivity (profit/energy), and water productivity (profit/water), while mitigating environmental damage (damage to groundwater resources/output) and ensuring food security in an arid watershed in Iran. The long Ashton research station weather generator (LARS-WG) and the coupled model intercomparison project 6 (CMIP6) were employed to project climate parameters for both future dry and wet conditions. The sustainability of the optimal solutions was then assessed using a hybrid criteria importance through intercriteria correlation (CRITIC)-VIKOR approach. The optimal solutions revealed a reduction in the land under cultivation and produced less water-intensive crops. The optimization model can ensure WEF security, enhancing agricultural system sustainability by optimizing crop cultivation patterns and resource allocation. Current crop choices were highly inefficient with the bigger changes being from the current crops to optimal crops. Climate change showed a substantial but lesser influence on optimal crop choice.

ABSTRACT Objective: This study was designed to investigate the possible effect of the insulin receptor substrate 1 (IRS1) gene rs1801276 polymorphism on the risk of nonalcoholic fatty liver disease (NAFLD). Subjects and methods: The rs1801276 polymorphism was investigated in 127 controls and 123 biopsy-proven NAFLD patients using PCR-RFLP. Results: No deviation from Hardy-Weinberg equilibrium was discovered for the rs1801276 variant of IRS1 in either NAFLD patients or controls (P>0.05). The distribution of different rs1801276 genotypes and alleles showed significant variations between controls and NAFLD patients. In comparison to rs1801276 ‘CC’ genotype, the "GG+GC" genotype occurred less frequently in NAFLD patients than in controls, which also persisted after adjustment for confounding factors (P = 0.041, OR = 0.60, 95% CI = 0.45-0.93). In comparison with the IRS1 rs1801276 "C" allele, the "G" allele was significantly less prevalent in NAFLD patients than in controls (P = 0.045, OR = 0.69, 95% CI = 0.58-0.91). Conclusions: For the first time, we reported a significant association between the IRS1 rs1801276 polymorphism and biopsy-proven NAFLD. More studies are required to further elucidate the contribution of the IRS1 gene to NAFLD susceptibility.

BackgroundMetabolic syndrome (MetS) prevalence has increased globally.The evidence shows thatdiet and gut microbial metabolites includingtrimethylamine N-oxide (TMAO) and kynurenine (KYN) play an important role in developing MetS. However, there is a lack of evidence on associations between between diet and these metabolites. This study aimed to investigate the interaction between dietary nitrate/nitrite and gut microbial metabolites (TMAO, KYN) on MetS and its components.MethodsThis cross-sectional study included 250 adults aged 20–50 years. Dietary intake was assessed using food frequency questionnaires (FFQ), and serum TMAO and KYN levels were measured. MetS was defined usingthe National Cholesterol Education Program Adult Treatment Panel (NCEP ATP III) criteria.ResultThe ATPIII index revealed an 11% prevalence of metabolic syndrome among the study participants. After adjusting for confounders, significant positive interactions were found: High animal-source nitrate intake and high TMAO levels with elevated triglycerides (TG) (p interaction = 0.07) and abdominal obesity (p interaction = 0.08). High animal-source nitrate intake and high KYN levels with increased TG (p interaction = 0.01) and decreased high-density lipoprotein cholesterol (HDL) (p interaction = 0.01).Individuals with high animal-source nitrite intake and high TMAO levels showed increased risk of hypertriglyceridemia (OR: 1.57, 95%CI: 0.35–2.87, p = 0.05), hypertension (OR: 1.53, 95%CI: 0.33–2.58, p = 0.06), and lower HDL (OR: 1.96, 95%CI: 0.42–2.03, p = 0.04). Similarly, high animal-source nitrite intake with high KYN levels showed lower HDL (OR: 2.44, 95%CI: 1.92–3.89, p = 0.07) and increased risk of hypertension (OR: 2.17,95%CI: 1.69–3.40, p = 0.05). Conversely, Negative interactions were found between high plant-source nitrate/nitrite intake with high KYN and TMAO levels on MetS and some components.ConclusionThere is an interaction between dietary nitrate/nitrite source (animal vs. plant) and gut microbial metabolites (TMAO and KYN) on the risk of of MetS and its components. These findings highlight the importance of considering diet, gut microbiome metabolites, and their interactions in MetS risk assessment.

Traditional lecturing is the dominant method of teaching mathematics in undergraduate mathematical courses in many countries, whereas active student-centered approaches such as inquiry-based learning have been shown in some instances to be more effective. Most teaching resources (inquiry-based tasks) available at the tertiary level are related to calculus, linear algebra, and differential equations courses. In this paper, we focus on using an inquiry-based approach to explore the teaching and learning of vertex coloring, a common topic in graph theory and undergraduate discrete mathematical courses. We designed seven inquiry-based tasks related to vertex coloring to teach vertex coloring in an undergraduate graph theory course to students majoring in mathematics. In sharing these tasks, describing students' engagement with them, and discussing how these tasks were perceived by the students and lecturer, we hope to promote using inquiry-based tasks in undergraduate discrete mathematical courses.

Mathematical objects are the outcomes of human discourse and come to life through the process of objectification. Primary and concrete discursive objects (d-objects) play an important role in this process, forming different realizations through the objectification process. In the present study, we analyze the written discourses about the derivative at a point in fourteen Year 11 and Year 12 Iranian calculus textbooks over 42 years (1979-2020) in terms of primary objects, concrete d-objects, and the realizations used in them, here based on Sfard's commognitive theory. The research method is a qualitative content analysis in which the analysis units were texts, examples, activities, and exercises in the textbooks. The results show that out of the 14 textbooks, only five included primary and concrete d-objects. The other textbooks only used abstract objects in their written discourse about the derivative. The pictures (visual mediators) that were used as primary objects gradually changed from schematic to real colored photos, and locally developed technologies and cultural elements were included in the new textbook editions. Additionally, the number of concrete d-objects increased in the new editions. In terms of the realizations, the number of roots also increased over time; however, none of the textbooks had all five main realizations (i.e., symbolic, graphical, verbal, numerical, and physical) for the derivative at a point. The realization tree developed as part of this study can be used as an analytical framework to analyze calculus textbooks in other contexts and can be used by teachers and lecturers to help students have explorative participation in discourse on the derivative.

Current views on the teaching of differential equations (DEs) are shifting towards the use of graphical and numerical methods. Motivated by recent research suggesting that puzzle-based learning (PzBL) can improve the teaching and learning of STEM subjects and by the lack of relevant studies for DEs, we designed two tasks--sophism and paradox--to explore undergraduate engineering students' conceptual understanding of a classical topic--exact DEs--and to analyse the process of meaning-making during collaborative learning in small groups. One hundred and thirty-five undergraduate engineering students from a public university in Iran participated. In response to recent research signalling the tendency of the students to procedural learning of DEs, we analyse how the students in our study engaged in small group work on puzzle tasks, gaining a more conceptual understanding of exact DEs and acknowledging the efficiency of PzBL in their responses to a questionnaire and in interviews.

Background. Warts are a common skin disease affecting individuals of all ages worldwide. This clinical trial aims to compare the effectiveness of furosemide 0.125 Percent topical gel and KOH 10 Percent topical gel in treating patients with warts. Methods. Patients diagnosed with warts by dermatologists were included in the study and treated with either 0.125 Percent furosemide or 10 Percent KOH for two months. Patients were examined and imaged at the beginning of the study and in weeks 4 and 8 to assess the number, diameter, and height of warts and complications. Results. The study included 40 patients (48 lesions) with common warts, with 20 patients in each intervention group. In the furosemide group, the average diameter of warts decreased from 4.25 ± 1.43 mm in the first visit to 4.14 ± 1.47 mm in the final visit. In contrast, the average diameter of warts in the KOH group decreased from 3.89 ± 1.67 mm to 3.02 ± 1.49 mm. No complications were reported in the furosemide group, whereas seven complications related to redness and burning were observed in the KOH group. Conclusion. Furosemide 0.125 Percent is effective and safe for treating skin warts. However, it is less effective than KOH in reducing the diameter and height of warts. This study's findings suggest that furosemide can be a promising alternative to KOH in treating warts, especially for patients with sensitive skin or those who experience complications with KOH treatment. Further research is needed to determine the optimal treatment duration and dosage of furosemide for treating warts. Practical Implications. We can find new ways to reduce complications in treating warts.

Aim: Islets of Langerhans are more sensitive to oxidative damage because of their low antioxidant capacity. In diabetes, methylglyoxal (MG) accumulates in the pancreas. The present study examined the effect of crocin on oxidative stress induced by MG in isolated Langerhans islets from male mice. Material and Methods: Twenty-four male mice weighing 20 to 25 g were prepared. The isolated Langerhans islets were transferred to the culture medium. Oxidative stress was induced through MG administration for 30 min, and then 10, 20, 30, and 40 μM of crocin was used for 2 h. Samples were divided into seven groups with 2.8, 5.6, and 16.7 mM glucose concentrations: control, MG 300 μM, MG+glibenclamide 10 μM, and MG+crocin in four doses of 10, 20, 30, and 40 μM. At the end, the islet’s insulin, antioxidant levels, and lipid peroxidation were assessed by ELISA and calorimetry methods. Results: Increased levels of malondialdehyde (MDA) in MG groups significantly decreased in 2.8 (p=0.008), 5.6 (p=0.004), and 16.7 (p˂0.001) mM glucose concentrations, with administration of 30 and 40 μM crocin. Total antioxidant capacity (TAC) was reduced in MG groups (p˂0.001) and significantly restored in all crocin-treated groups in 2.8, 5.6, and 16.7 mM glucose concentrations. Also, a significant decrease in insulin secretion and content was observed in MG groups of all three glucose concentrations (p˂0.001). Crocin at high doses improved these alterations. Conclusion: MG caused oxidative damage and reduced insulin secretion in isolated islets. Crocin improved the antioxidant defense system, diminished MDA, and increased insulin secretion.

This study aims to develop a robust and efficient system to identify ties and ballasts in motion using a variety of non-contact sensors mounted on a robotic rail cart. The sensors include distance LiDAR sensors and inductive proximity sensors for ferrous materials to collect data while traversing railroad tracks. Many existing tie/ballast health monitoring devices cannot be mounted on Hyrail vehicles for in-motion inspection due to their inability to filter out unwanted targets (i.e., ties or ballasts). The system studied here addresses that limitation by exploring several approaches based on distance LiDAR sensors. The first approach is based on calculating the running standard deviation of the measured distance from LiDAR sensors to tie or ballast surfaces. The second approach uses machine learning (ML) methods that combine two primary algorithms (Logistic Regression and Decision Tree) and three preprocessing methods (six models in total). The results indicate that the optimal configuration for non-contact, in-motion differentiation of ties and ballasts is integrating two distance LiDAR sensors with a Decision Tree model. This configuration provides rapid, accurate, and robust tie/ballast differentiation. The study also facilitates further sensor and inspection research and development in railroad track maintenance.

Sustainable water resources management involves social, economic, environmental, water use, and resources factors. This study proposes a new framework of strategic planning with multi-criteria decision-making to develop sustainable water management alternatives for large scale water resources systems. A fuzzy multi-criteria decision-making model is developed to rank regional management alternatives for agricultural water management considering water-resources sustainability criteria. The decision-making model combines hierarchical analysis and the fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The management alternatives were presented spatially in the form of zoning maps at the level of irrigation zones of the study area. The results show that the irrigation management zone No.3 (alternative A3) was ranked first based on agricultural water demand and supply management in five among seven available scenarios, in which the scenarios represents a possible combination of weights assigned to the weighing criteria. Specifically, the results show that irrigation management zone No.3 (alternative A3) achieved the best ranking values of 0.151, 0.169, 0.152, 0.174 and 0.164 with respect to scenarios 1, 4, 5, 6 and 7, respectively. However, irrigation management zone No.2 (alternative A2) achieved the best values of 0.152 and 0.150 with respect to the second and third scenarios, respectively. The model results identify the best management alternatives for agricultural water management in large-scale irrigation and drainage networks.