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BackgroundEarly detection and localization of myocardial infarction (MI) can reduce the severity of cardiac damage through timely treatment interventions. In recent years, deep learning techniques have shown promise for detecting MI in echocardiographic images. Existing attempts typically formulate this task as classification and rely on a single segmentation model to estimate myocardial segment displacements. However, there has been no examination of how segmentation accuracy affects MI classification performance or the potential benefits of using ensemble learning approaches. Our study investigates this relationship and introduces a robust method that combines features from multiple segmentation models to improve MI classification performance by leveraging ensemble learning.Materials and MethodsOur method combines myocardial segment displacement features from multiple segmentation models, which are then input into a typical classifier to estimate the risk of MI. We validated the proposed approach on two datasets: the public HMC-QU dataset (109 echocardiograms) for training and validation, and an E-Hospital dataset (60 echocardiograms) from a local clinical site in Vietnam for independent testing. Model performance was evaluated based on accuracy, sensitivity, and specificity.ResultsThe proposed approach demonstrated excellent performance in detecting MI. It achieved an F1 score of 0.942, corresponding to an accuracy of 91.4%, a sensitivity of 94.1%, and a specificity of 88.3%. The results showed that the proposed approach outperformed the state-of-the-art feature-based method, which had a precision of 85.2%, a specificity of 70.1%, a sensitivity of 85.9%, an accuracy of 85.5%, and an accuracy of 80.2% on the HMC-QU dataset. On the external validation set, the proposed model still performed well, with an F1 score of 0.8, an accuracy of 76.7%, a sensitivity of 77.8%, and a specificity of 75.0%.ConclusionsOur study demonstrated the ability to accurately predict MI in echocardiograms by combining information from several segmentation models. Further research is necessary to determine its potential use in clinical settings as a tool to assist cardiologists and technicians with objective assessments and reduce dependence on operator subjectivity. Our research codes are available on GitHub at https://github.com/vinuni-vishc/mi-detection-echo.

Spirocercosis is caused by Spirocerca spp., which is a chronic disease and might cause life-threatening due to forming cancer in oesophagus in canid carnivores. There are limited studies involving spirocercosis in domestic dogs. Thus, this study aims to investigate the prevalence and analyse risk factors involved in the S. lupi infection in Mekong Delta in Vietnam. In total, 400 fecal samples from domestic dogs were collected from May 2020 to May 2021. The overall prevalence of spirocercosis in domestic dogs in the Mekong Delta was 10.50% by copromicroscope and PCR methods. PCR targeted to the housekeeping gene cytochrome c oxidase I (cox-1) was applied to identify species of Spirocerca spp. and analyse the phylogenetic tree. Outdoor dogs had 5.48 times (CI 95% = 2.45-11.690, p < 0.001) higher risks of S. lupi infection compared to indoor dogs. Besides, seasons and age showed a correlation to the increase the risk of S. lupi infection, while neither dog breeds nor gender influenced the prevalence of this species. The cytochrome c oxidase I (cox-1) gene sequence of S. lupi in the Mekong Delta showed the high homologues to the S. lupi isolates in India, Israel, and the North of Vietnam and belonged to the S. lupi genotype 2.

Traditional pork shops play an essential role in delivering pork, the most popular food in Vietnam, to consumers. Studies have shown the need for investment in training and equipment to improve the safety of pork sold at traditional shops. However, it remains unclear how consumers perceived improvement to the hygiene in pork shops and if they are ready to pay premium prices for safer products. This study used an experimental approach to determine consumers' perception and assessment of improved pork shops and their willingness to pay (WTP) for pork products. A total of 152 respondents in two provinces in Vietnam joined in a Becker–DeGroot–Marschak (BDM) mechanism experiment to collect data on WTP for pork from typical and upgraded pork shops. A questionnaire was used to record consumers' perceptions and assessments of the pork shops and products. Overall, consumers were willing to pay 20% more for upgraded fresh pork than for what is currently available on the market. Consumers trusted in the effectiveness of the upgraded intervention and the quality of pork at the pork shop, which increased their WTP for the upgraded pork. Concerns about contaminated pork had a negative impact on the WTP for typical pork, while the high frequency of pork consumption and the existence of elderly family members led to higher WTP for both products. The findings indicate the potential economic benefit of upgrading pork shops, which would be an important driver to motivate sellers to improve food safety.

School reform efforts are situated within social and political contexts and, as such, are susceptible to the commonsense discourses circulating through, and shaping, society. Two discourses prevalent in US education reform are those perpetuating the ideologies of neoliberalism and neoconservatism. These ideologies are inherently contradictory--with the former promoting a small state and the latter a strong state--but converge to promote their agendas, shaping school reform efforts. "How" this occurs is not always clear, especially in rural contexts, where there has been limited attention to ideological discourses' relation to schooling. In this analysis, we describe how dominant, yet contradictory, discourses of neoliberalism and neoconservatism are resolved in a rural context. We find that the leaders of one rural, public school district identified fifth-grade number sense as a problem of practice needing improvement--framing the cause of their problem as misalignment and the solution as consistency within and across grade levels. In doing so, district leaders' conversations were limited to those of standardization (e.g., state-mandated mathematics standards, approaches to timed-fact tests, and curriculum between grade levels). Alignment as a frame excluded conversations related to deeper considerations, such as students' experiences in mathematics or issues of equity. We find that dominant discourses constrain the ways district leaders frame their mathematics-related problem and work through the frame (in this case, one of alignment) to resolve inherent contradictions and advance their agendas. We suggest that these discourses serve to distract from potentially more pressing issues in education.

Underwater vehicles are a powerful tool that can assist oceanologists with measuring the state of oceans on a large scale. The heading control is essential for the underwater vehicle to follow a specific path. This study describes the general decoupled dynamics of underwater vehicles, which is a nonlinear second-order differential equation considering linear and quadratic damping hydrodynamics. A novel aspect of this study is the development of a new analytical solution for the second-order nonlinear differential equation, which involves the heading motion of the underwater vehicle. In this study, the time-optimal trajectory is formulated as the closed-form solution for the heading dynamics of the underwater vehicle. The concept of this trajectory is based on the shortest arrival time when the maximum force from the thrusters is applied to the underwater vehicle. Finally, a simulation of the time-optimal trajectory and evaluation of the robustness of the controller were demonstrated in order to verify the effectiveness of the proposed trajectory for controlling underwater vehicles.

The complex pathology of mild traumatic brain injury (mTBI) is a main contributor to the difficulties in achieving a successful therapeutic regimen. Thyroxine (T4) administration has been shown to prevent the cognitive impairments induced by mTBI in mice but the mechanism is poorly understood. To understand the underlying mechanism, we carried out a single cell transcriptomic study to investigate the spatiotemporal effects of T4 on individual cell types in the hippocampus and frontal cortex at three post-injury stages in a mouse model of mTBI. We found that T4 treatment altered the proportions and transcriptomes of numerous cell types across tissues and timepoints, particularly oligodendrocytes, astrocytes, and microglia, which are crucial for injury repair. T4 also reversed the expression of mTBI-affected genes such as Ttr, mt-Rnr2, Ggn12, Malat1, Gnaq, and Myo3a, as well as numerous pathways such as cell/energy/iron metabolism, immune response, nervous system, and cytoskeleton-related pathways. Cell-type specific network modeling revealed that T4 mitigated select mTBI-perturbed dynamic shifts in subnetworks related to cell cycle, stress response, and RNA processing in oligodendrocytes. Cross cell-type ligand-receptor networks revealed the roles of App, Hmgb1, Fn1, and Tnf in mTBI, with the latter two ligands having been previously identified as TBI network hubs. mTBI and/or T4 signature genes were enriched for human genome-wide association study (GWAS) candidate genes for cognitive, psychiatric and neurodegenerative disorders related to mTBI. Our systems-level single cell analysis elucidated the temporal and spatial dynamic reprogramming of cell-type specific genes, pathways, and networks, as well as cell-cell communications as the mechanisms through which T4 mitigates cognitive dysfunction induced by mTBI.

Teacher educators globally have argued that developing coherent programs can combat the fragmentation that often characterizes teacher education and better support teacher learning. Yet, there is little research on coherence in mathematics teacher education, especially from the perspectives of preservice teachers. To that end, in this article, we report how 13 secondary mathematics preservice teachers (PSTs) from one teacher education program perceived their program as coherent, specifically attending to the ideas and practices PSTs engaged with and the settings in which they engaged with those ideas/practices. Based on participatory diagramming interviews and network analysis, we found that PSTs experienced two main sources of incoherence. First, although PSTs had opportunities to learn about equity from multiple settings, they did not perceive that equity and other aspects of mathematics instruction together were coherently organized. Second, PSTs reported learning about two opposing instructional approaches--direct instruction and inquiry-based instruction. PSTs reported that opportunities to learn about inquiry-based instruction were primarily isolated to courses taught by the mathematics education program and were contradicted by learning and experiencing direct instruction in their special education courses, mathematics courses, and field and student teaching experiences. Findings highlight a need to attend to issues of equity, as well as connections among university coursework and between coursework and field. Based on our findings, we conclude with implications for how teacher education programs might respond to and engage with incoherence to support PST learning.

This study aims to explore the relationship between the influential factors of online learning and the satisfaction of economics and business majors with the quality of their training in the context of the COVID-19 pandemic. A total of 900 students in private universities completed a questionnaire. The principal findings of this research are that the students are satisfied with their online learning and that learning conferencing software is the most important driving factor leading to the students' satisfaction when compared with learning conditions and learning devices. Another interesting finding is that the experience of using learning conferencing software results in a slight difference in the students' perceived level of satisfaction, adding that users with more than two years' experience are more satisfied with their training quality than users with less than one year's experience. However, the results also show that students want to switch to offline learning when the pandemic is over. This study should, therefore, be of value to higher education authorities wishing to understand their students' perceptions of online learning. In addition, results from the study suggest more managerial approaches as well as improve the online teaching quality during the pandemic.

BackgroundVietnam’s mental health care system is undergoing significant changes since the government has initiated large-scale programs to reform and develop the mental health care infrastructure. Cultural belief systems on mental illnesses influence help-seeking behavior and compliance. This study investigates the belief systems about people with schizophrenia and depression among people living in the Hanoi area.Method1077 Vietnamese participants answered two open-ended questions after reading an unlabeled vignette describing a character with the symptoms of schizophrenia or depression. The answers were analyzed using thematic analysis.ResultsOf all participants, 88,4% associated the presented cases with a mental illness, with 91,5% in the case of schizophrenia and 85,1% in the case of depression, so both disorders were conceptualized as mental illnesses. 18,6% mentioned depression when presented with the depression vignette, while only 3,6% recognized schizophrenia in the schizophrenia condition.ConclusionsAlmost 9 out of 10 participants considered the presented cases as an example of mental illness, suggesting a high mental health awareness among our participants. The majority did not identify the presented cases as examples of schizophrenia or depression, reflecting little familiarity with Western mental health concepts. It could be interpreted as a sign of relatively low mental health literacy among the study participants.

As a developing countries, Vietnam has been facing a myriad of challenges in various aspects during the COVID-19 pandemic. Educational sector is not an exception as it is currently suffering the heavy consequences of the constant disruptions stemming from the switching to online learning. This study was conducted with the aim of surveying and evaluating the views of students of the Faculty of Medicine at Nguyen Tat Thanh University on the influence of online learning on learning quality. Using data from survey questionnaires, the results show that the online learning has impacted different learning aspects of students such as: time management, online satisfaction, training problems. At the same time, the study also recognizes the contributions of students in improving the quality of online teaching of Nguyen Tat Thanh University.

Developmental neural activity is a common feature of neural circuit assembly. Although glia have established roles in synapse development, the contribution of neuron-glia interactions to developmental activity remains largely unexplored. Here we show that astrocytes are necessary for developmental activity during synaptogenesis in Drosophila. Using wide-field epifluorescence and two-photon imaging, we show that the glia of the central nervous system participate in developmental activity with type-specific patterns of intracellular calcium dynamics. Genetic ablation of astrocytes, but not of cortex or ensheathing glia, leads to severe attenuation of neuronal activity. Similarly, inhibition of neuronal activity results in the loss of astrocyte calcium dynamics. By altering these dynamics, we show that astrocytic calcium cycles can influence neuronal activity but are not necessary per se. Taken together, our results indicate that, in addition to their recognized role in the structural maturation of synapses, astrocytes are also necessary for the function of synapses during development.

In vertebrates, stimulus-independent activity accompanies neural circuit maturation throughout the developing brain1,2. The recent discovery of similar activity in the developing Drosophila central nervous system suggests that developmental activity is fundamental to the assembly of complex brains3. How such activity is coordinated across disparate brain regions to influence synaptic development at the level of defined cell types is not well understood. Here we show that neurons expressing the cation channel transient receptor potential gamma (Trpγ) relay and pattern developmental activity throughout the Drosophila brain. In trpγ mutants, activity is attenuated globally, and both patterns of activity and synapse structure are altered in a cell-type-specific manner. Less than 2% of the neurons in the brain express Trpγ. These neurons arborize throughout the brain, and silencing or activating them leads to loss or gain of brain-wide activity. Together, these results indicate that this small population of neurons coordinates brain-wide developmental activity. We propose that stereotyped patterns of developmental activity are driven by a discrete, genetically specified network to instruct neural circuit assembly at the level of individual cells and synapses. This work establishes the fly brain as an experimentally tractable system for studying how activity contributes to synapse and circuit formation.