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The study complements previous research on a case study of chemistry lesson plans design and teaching. It has been found that chemistry education in the Gambia has been challenged by ineffective lesson plans design and teaching, and laboratory resources. The consequences have been unsatisfactory learning outcomes. However, what could lead to unsatisfactory learning outcomes in chemistry if basic stoichiometry is considered challenging? This has led the present study to develop a survey research method to assess students' misconceptions on basic stoichiometry. Through a systematic random sampling technique, 285-grade eleventh students were selected. The topics covered in the study included interpreting the pH of common substances, balancing basic stoichiometric equations, and inferences of experimental results. Students' responses to misconception survey questions were reviewed and analysed. The results indicated that students could be taught some basic principles of stoichiometry. Students who were challenged to correct inferences from experimental results need to develop their knowledge better. Accordingly, the study concluded that chemistry education can indicate the success of introducing basic stoichiometry, including referencing to the lower grades, rather than secondary grades. Nevertheless, what this study could recommend was to examine the possible source and cause of such misconceptions concerning basic stoichiometry reactions and balancing.

One of the main purposes of technology integration was for effective teaching and learning. The model of technological pedagogical content knowledge (TPACK) was the suggested framework that could be applied in different facets of the teaching and learning process. Information communication tools (ICT) are the common infrastructures used for this process, and studies of TPACK application were mainly focused on normal desktop computers, and at the university level. However, there were uncommon studies of smart technologies such as SMART Board and SMART Notebook software at the secondary level, concerning TPACK applications. Against this background, the present study evaluated secondary school teachers on the TPACK applications in smart classrooms, as well as its effect on students' performance in chemistry. Through explanatory sequential mixed method design, results were highlighted and interpreted. These included lesson observation for quantitative data on four categories of knowledge: content knowledge, technological knowledge, technological pedagogical knowledge, and pedagogical content knowledge and students' performance in chemistry. While qualitative data about views were thematically analysed into strengths and challenges, as well as suggestions regarding TPACK applications and improving teaching and learning. The study involved seven teachers and 142 students, who were selected using a convenient sampling technique. The results revealed that teachers demonstrated the capacity to connect all categories of knowledge, develop, and conduct teaching where technology, pedagogy, and content interact. However, as the observed teachers acknowledged, it is challenging to overcome traditional teaching methods. This is due to several external factors, most notably the limited availability of digital equipment, and inadequate technology training, among others, which can improve the TPACK applications and promote students' engagement and learning. Further, the result of the intervention showed that teachers need continuous professional development, as it reflects significantly (p ?0.05) on students' performance in chemistry. These findings could serve as a foundation for creating policies that prioritise allocating funds to public schools for educational technology tools that will help teachers and students improve the teaching-learning process.

This study examines the written and visual results of a participatory systems-mapping process used to explore undergraduate research at a large, public research university in the United States. With the university's transition to a high-impact practice model, the institutional value of undergraduate research has increased, but challenges remain in implementing the practice equitably and inclusively, especially in the complex environment of higher education. The systems-mapping process reveals the subtle, often conflicting dynamics that underlie the undergraduate research enterprise, while simultaneously supporting the emergence of a shared vision, or story, of what the undergraduate research experience could be.

In the field of education for sustainable development (ESD), many authors refer to the notion of 'experience' and associated concepts. This highlights some of the theoretical underpinnings of ESD, a disciplinary field which, in France, became generalized in schools as of 2004. It has since been the subject of numerous research studies and undergone many institutional and professional changes. The present work first identifies the role that experience occupies in the educational field of ESD, according to educational researchers. It then explores the state and implementation of the notion in practice among professionals who use activities aimed at educating and training learners on the subject of sustainable development (SD). The gap we observe between various scientific meanings of the notion and its appropriation in professional contexts suggests that there are potential avenues for developing and improving teacher training by enriching ESD practices.

The chemistry laboratory is an impactful platform for introducing inquiry and developing science practice skills. We designed a short lab course to introduce incremental levels of inquiry, also to interconnect and integrate different domains of chemistry. Indigo dye was the central theme of this short course wherein students synthesized indigo, dyed the yarns, analyzed the generated wastewater, and, finally, devised a treatment plan. This article describes the implementation of this short course as an explorative case study with 12 first-year undergraduate participants (4 small groups). Our study aimed to understand how science practice skills could be developed through the incremental approach to inquiry levels. The lab task sheet, lab reports, and transcripts of the group discussion were used as the data for qualitative analysis. Additionally, responses in the questionnaire were analyzed to understand students' perceptions and their experiences in this course. The results indicate that introducing inquiry at an incremental level is a promising approach to help students develop science practice skills. The first two experiments helped students to learn to formulate a hypothesis. The third and fourth experiments helped students to learn to design experiments. The quality of the hypothesis and explanation offered for observations enhanced with the progress of the course. The lab report pointers helped students to communicate their results systematically and helped to establish a connection between the hypothesis, data, and explanations, favoring the engagement with science practice skills.

Introduction: Infective endocarditis is a serious infection of the endocardium, especially the heart valves, which is associated with a high mortality rate. It generally occurs in patients with altered and abnormal cardiac architecture combined with exposure to bacteria from trauma and other potentially high-risk activities with transient bacteremia. Aim: The aim of the study was to develop a reproducible periodontitis-endocarditis model in a rat that can be used to answer the question of how the administration of antibiotic prophylaxis before tooth extraction affects the prevalence of bacteremia and the incidence of endocarditis. Materials and methods: Thirty-five female Wistar rats were divided into three groups: periodontitis group (PG): ligatures were placed bilaterally on maxillary first molars, and the maxillary molars were extracted after 30 T; endocarditis group (EG): in addition to PG, aortic valve injury was performed with simulated prosthetic material before extraction; antibiotic prophylaxis group (AG): in addition to EG, a single-shot antibiotic administration was performed 30–60 minutes before extraction. Periodontal indices were collected, blood samples were microbiologically analyzed. Hearts were examined histologically after euthanasia. Results: On the day of extraction, 93% of the ligatures were still in situ. The average approximal plaque index of maxillary first molars was 92%. The average papilla bleeding index according to Saxer and Mühlemann of the first molar in the first quadrant was grade 3, in the second quadrant – grade 2. The average probing depth of the first molar in the first quadrant was 3 mm, in the second – 2 mm. Endocarditic changes were identified in 20% in the AG group, 60% in the EG, and 0% in the PG control group. A successful model was developed by reliably developing endocarditis and periodontitis. Specific marker germs for periodontitis could be detected in blood cultures. The effectiveness of antibiotic prophylaxis prior to tooth extraction in groups at risk of endocarditis has been demonstrated in animal models. Conclusions: In the present experimental animal study, a reproducible model could be developed by creating a manifest periodontal lesion, which, in connection with an aortic valve lesion and a tooth extraction, triggers bacteremia. Clinical relevance The model could act as a basis for further studies on the topic to answer remaining questions related to oral pathogens and IE.

The need for shifting the expository laboratory instruction style to inquiry-based approaches is widely acknowledged. Problem-based learning (PBL), one of the inquiry-based approaches, advocates students' self-directed learning. The literature indicates that scaffolding students' independent learning is necessary for a PBL environment. In our study, we provided scaffolds such as a precursor task, reading material, and structured group discussion to facilitate the planning of a PBL task on indigo dyeing wastewater treatment. In this paper, we describe how these three scaffolds integrated within the PBL style contributed to students' learning as per the stages of Kolb's Experiential Learning Cycle (ELC). We analyzed the level of the abstract conceptualization stage of ELC through students' experimental designs (EDs) of the PBL task. The results of the qualitative analysis of the scaffolded and un-scaffolded groups suggest that scaffolded students' experimental design scores are higher. The qualitative results indicate that the structured group discussion influences the EDs planned by students more than the precursor task and the reading material. All three scaffolds help in the reflective learning and planning of executable EDs for a PBL task. The study indicates that students transitioning into the inquiry laboratory benefit from the inclusion of scaffolding.

Introduction: While the electrocardiogram (ECG) for pulmonary embolism typically shows tachycardia or evidence of right heart strain, it can demonstrate ischemic changes similar to acute coronary syndrome.Case Report: The patient in this case presented with syncope, chest pain, and an ECG showing an anterior acute myocardial infarction (AMI) without evidence of right heart strain. His cardiac catheterization showed no coronary artery occlusions, but some signs of pulmonary embolism (PE), which was confirmed on computed tomography angiography of the chest.Conclusion: This case demonstrates that PE should be high on the differential for AMI and describes an uncommonly encountered mimic for classic ST-elevation myocardial infarction ECG changes. Further diagnostics to confirm the diagnosis should be obtained when indicated.

One of the main purposes of technology integration was for effective teaching and learning. The model of technological pedagogical content knowledge (TPACK) was the suggested framework that could be applied in different facets of the teaching and learning process. Information communication tools (ICT) are the common infrastructures used for this process, and studies of TPACK application were mainly focused on normal desktop computers, and at the university level. However, there were uncommon studies of smart technologies such as SMART Board and SMART Notebook software at the secondary level, concerning TPACK applications. Against this background, the present study evaluated secondary school teachers on the TPACK applications in smart classrooms, as well as its effect on students' performance in chemistry. Through explanatory sequential mixed method design, results were highlighted and interpreted. These included lesson observation for quantitative data on four categories of knowledge: content knowledge, technological knowledge, technological pedagogical knowledge, and pedagogical content knowledge and students' performance in chemistry. While qualitative data about views were thematically analysed into strengths and challenges, as well as suggestions regarding TPACK applications and improving teaching and learning. The study involved seven teachers and 142 students, who were selected using a convenient sampling technique. The results revealed that teachers demonstrated the capacity to connect all categories of knowledge, develop, and conduct teaching where technology, pedagogy, and content interact. However, as the observed teachers acknowledged, it is challenging to overcome traditional teaching mrthods. This is due to several external factors, most notably the limited availability of digital equipment, and inadequate technology training, among others, which can improve the TPACK applications and promote students' engagement and learning. Further, the result of the intervention showed that teachers need continuous professional development, as it reflects significantly (p ˂.05) on students' performance in chemistry. These findings could serve as a foundation for creating policies that prioritise allocating funds to public schools for educational technology tools that will help teachers and students improve the teaching-learning process. [ABSTRACT FROM AUTHOR]

Abstract Methane emissions along the natural gas supply chain are critical for the climate benefit achievable by fuel switching from coal to natural gas in the electric power sector. For Germany, one of the world’s largest primary energy consumers, with a coal and natural gas share in the power sector of 35% and 13%, respectively, we conducted fleet-conversion modelling for reference year 2018, taking domestic and export country specific greenhouse gas (GHG)-emissions in the natural gas and coal supply chains into account. Methane leakage rates below 4.9% (GWP20; immediate 4.1%) in the natural gas supply chain lead to overall reduction of CO2-equivalent GHG-emissions by fuel switching. Supply chain methane emissions vary significantly for the import countries Russia, Norway and The Netherlands, yet for Germany’s combined natural gas mix lie with <

The aim of this article is to present the results of a research on the perception of INSPE trainers about the construction of initial training programs for primary school teachers and, more specifically, about the lessons and resources made available to trainee teachers to learn how to implement the school inclusion of pupils with disabilities in ordinary classes. Carried out with a didactic approach, our research highlights the predominance of personal relationships to the issues raised by inclusive schooling over institutional relationships which are struggling to be constructed and disseminated.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic recently. The prevalence and persistence of antibodies following a peak SARS-CoV-2 infection provides insights into the potential for some level of population immunity. In June 2020, we succeeded in testing almost half of the population of an Austrian town with a higher incidence of COVID-19 infection. We performed a follow-up study to reassess the prevalence of SARS-CoV-2-specific IgA and IgG antibodies with 68 participants of the previous study. We found that the prevalence of IgG or IgA antibodies remained remarkably stable, with 84% of our cohort prevailing SARS-CoV-2-specific antibodies (only a slight decrease from 93% 4 months before). In most patients with confirmed COVID-19 seroconversion potentially provides immunity to reinfection. Our results suggest a stable antibody response observed for at least 6 months post-infection with implications for developing strategies for testing and protecting the population.

Background: Since December 2019 the novel coronavirus (SARS-CoV-2) is the center of global attention due to its rapid transmission and toll on health care systems and global economy. Population-based serosurveys measuring antibodies for SARS-CoV-2 provide one method for estimating previous infection rates including the symptom-free courses of the disease and monitoring the progression of the epidemic.Methods: In June 2020 we succeeded in testing almost half of the population of an Austrian township (1,359 inhabitants) with a reported higher incidence for COVID-19 infections (17 PCR positive cases have been officially reported until the date of sample collection, i.e., 1.2% of the total population). We determined the prevalence of SARS-CoV-2-specific antibodies in this population, factors affecting, and symptoms correlated with prior infection. Antibodies were determined using a CE-certified quality-controlled ELISA test for SARS-CoV-2-specific IgG and IgA antibodies.Results: We found a high prevalence of 9% positive antibodies among the town population in comparison to 6% of the neighboring villages. This was considerably higher than the officially known RT-PCR-approved COVID-19 cases (1.2%) in the town population. Twenty percent of SARS-CoV-2-antibody positive cases declared being asymptomatic in a questionnaire. On the other hand, we identified six single major symptoms, including anosmia/ageusia, weight loss, anorexia, general debility, dyspnea, and fever, and especially their combination to be of high prognostic value for predicting SARS-CoV-2 infection in a patient.Conclusions: This population study demonstrated a high prevalence of antibodies to SARS-CoV-2 as a marker of past infections in an Austrian township. Several symptoms revealed a diagnostic value especially in combination.

The Lower Austrian Wachau region was an early COVID-19 hotspot of infection. As previously reported, in June 2020, after the first peak of infections, we determined that 8.5% and 9.0% of the participants in Weißenkirchen and surrounding communities in the Wachau region were positive for immunoglobulin G (IgG) and immunoglobulin A (IgA) antibodies against the receptor-binding domain of the spike protein of SARS-CoV-2, respectively. Here, we present novel data obtained eight months later (February 2021) from Weißenkirchen, after the second peak of infection, with 25.0% (138/552) and 23.6% (130/552) of participants that are positive for IgG and IgA, respectively. In participants with previous IgG/IgA positivity (June 2020), we observed a 24% reduction in IgG levels, whereas the IgA levels remained stable in February 2021. This subgroup was further analyzed for SARS-CoV-2 induced T cell activities. Although 76% (34/45) and 76% (34/45) of IgG positive and IgA positive participants, respectively, showed specific T cell activities (upon exposure to SARS-CoV-2 spike protein-derived peptides), those were not significantly correlated with the levels of IgG or IgA. Thus, the analyses of antibodies cannot surrogate the measurement of T cell activities. For a comprehensive view on SARS-CoV-2-triggered immune responses, the measurement of different classes of antibodies should be complemented with the determination of T cell activities.

Many species exhibit aggressive behaviors, and the intensity of aggression can be modulated by different factors. For instance, the neurotransmitter serotonin is negatively correlated with aggression, and selective serotonin reuptake inhibitors (SSRIs) are drugs used to increase the extracellular serotonin levels by blocking the reabsorption of serotonin into presynaptic neurons, leading to decreased aggression. Also, environmental enrichment--when an animal is placed in an artificial habitat that tries to mimic its natural habitat--has been shown to decrease aggression in captive animals. However, research on the interaction of factors that regulate aggression are not completely known and, specifically, the relationship between serotonin and environmental enrichment is not completely understood. The purpose of the experiment was to determine if environmental enrichment and SSRIs will decrease aggressive behaviors more so than each factor alone. It was hypothesized that male Betta fish (Betta splendens) exposed to SSRIs and held in enriched environments will show lower levels of aggression compared with controls, SSRIs alone, or enriched environments alone. The results revealed that SSRIs decrease aggressive behaviors, but environmental enrichment was not a significant predictor of aggressive behaviors. Likewise, the interaction between the SSRIs and environmental enrichment was not a significant predictor of aggressive behaviors. Therefore, our study supports previous studies that found SSRIs decrease aggression but also suggests that environmental enrichment either does not affect aggression in Betta fish or that our operationalization of environmental enrichment was not sufficient to change aggressive behaviors. [ABSTRACT FROM AUTHOR]