Ultrasonic surface acoustic wave elastography: A review of basic theories, technical developments, and medical applications.

Physiological and pathological changes in tissues often cause changes in tissue mechanical properties, making tissue elastography an effective modality in medical imaging. Among the existing elastography methods, ultrasound elastography is of great interest due to the inherent advantages of ultrasound imaging technology, such as low cost, portability, safety, and wide availability. However, most current ultrasound elastography methods are based on the bulk shear wave; they can image deep tissues but cannot image superficial tissues. To address this challenge, ultrasonic elastography methods based on surface acoustic waves have been proposed. In this paper, we present a comprehensive review of ultrasound-based surface acoustic wave elastography techniques, including their theoretical foundations, technical implementations, and existing medical applications. The goal is to provide a concise summary of the state-of-the-art of this field, hoping to offer a reliable reference for the further development of these techniques and foster the expansion of their medical applications.

Assessment of biosecurity measures in commercial poultry farms of Rajshahi district in Bangladesh.

The application of biosecurity measures in the poultry sector are essential. Developing and implementing daily biosecurity activities are considered effective methods to prevent infectious diseases on poultry farms. Appropriate farm settings and management reduce the possibility of disease transmission between farms. This study aimed to assess the current biosecurity status of commercial poultry farms in the Rajshahi district of Bangladesh. A cross-sectional study was conducted from June to November 2021, involving 204 poultry farmers in the Rajshahi district, using a multistage sampling technique. Data were collected through face-to-face interviews using a semi-structured questionnaire. The statistically significant (p < 0.05) results found were: most farmers reported that the visitors could not access their farms (broiler vs. layer: 68.1%, 77.0%). A higher proportion of broilers compared to layer farms used company's supplied feed (81.2% vs. 66.7%). A higher proportion of layer (97.8%) farms cleaned the farm's litter within 24 h compared to broiler farms (72.5%). Broiler farms had better records animal mortality than layer farms (76.8% vs. 60.0%). More layer (96.3%) farms compared to broiler (87.0%) farms implemented a vaccination program. The findings of this study revealed that biosecurity measures are well-practiced and implemented in most broiler and layer farms in this region except in a small number of farms. Government authorities should strictly enforce and monitor biosecurity measures in farms that do not practice essential biosecurity measures.

Evaluation of inflammatory cytokines in drug-naïve major depressive disorder: A systematic review and meta-analysis.

Objective: Altered levels of peripheral inflammatory and proinflammatory cytokine markers affect the different clinical stages of major depressive disorder (MDD). A concrete understanding of the causal mechanism of MDD is a prerequisite in developing treatment strategies and preventive plans. Here we aimed to conduct an updated systematic review and meta-analysis of studies assessing the association of C-reactive protein (CRP), INF-γ, MCP-1, and TNF-α in the peripheral fluid of drug-naïve MDD patients and healthy controls (HCs). Methods: We extracted articles from PubMed, ProQuest, PsycINFO, Web of Science, and Scopus databases from inception until 14 February 2021, to find relevant studies. In this meta-analysis, we included a total of 23 eligible studies (1,366 MDD patients and 1,342 controls) in the final meta-analysis. The Cochran's chi-square Q-test and I2-index were applied to measure the heterogeneity and inconsistency of all combined results. We selected a random-effect model during the analysis and measured publication biases using the funnel plot. We performed Bonferroni adjustment for multiple testing. Results: We found a high level of TNF-α in MDD patients than in control subjects Standardized Mean Difference (SMD) with a random-effects model: 1.04, 95% CI: 0.69-1.39, z = 5.84, p < 0.001). The levels of CRP (SMD with a random-effects model: 0.18, 95% CI: -0.85-1.23, z = 0.35, p = 0.73), INF-ɤ (SMD with a random-effects model: -0.05, 95% CI: -2.72-2.62, z = 0.03, p = 0.97), and MCP-1 (SMD with a random-effects model: 0.70, 95% CI: -0.09-1.49, z = 1.73, p = 0.08) were not significantly varies between MDD patients and HCs. Conclusion: The present study findings suggest the upregulated level of peripheral TNF-α but not CRP, INF-γ, and MCP-1 involve in depression. The elevated inflammatory cytokines confirmed the inflammatory state of depression. Therefore, inflammatory cytokines might serve as potential risk assessment markers in MDD.

Effect of prior immunisation with smallpox vaccine for protection against human Mpox: A systematic review.

Monkeypox is an emerging threat to humans since a new outbreak in May 2022. It is hypothesised that increasing the immunologically naive population after the cessation of the smallpox vaccination campaign in the 1980s is one of the leading causes of it. A literature search was conducted using different electronic databases including MEDLINE (through PubMed), SCOPUS, Web of Science, Cochrane library, and EMBASE for relevant studies. After duplication removal, abstract and title screening, and full-text screening were done, the data were extracted, tabulated, and analysed. The risk of bias was assessed following the Risk of Bias Assessment tool for Non-randomised Studies. We found a total of 1068 relevant articles and finally, we included 6 articles including 2083 participants. The studies suggested that smallpox is 80.7% efficacious to prevent human monkeypox and the immunity provided by prior smallpox vaccination is long-lasting. Moreover, the smallpox vaccination decreases the risk of human monkeypox by 5.2-folds. Two cross-sectional studies based on the Democratic Republic of the Congo (DRC) including a total of around 1800 monkeypox cases found that unvaccinated participants had 2.73 and 9.64-fold increased risk of monkeypox compared to the vaccinated participants. Other studies in USA and Spain also demonstrated that unvaccinated people were more prone to develop monkeypox than vaccinated people. Furthermore, monkeypox incidence has increased by 20 folds, 30 years after the cessation of the smallpox vaccination campaign in DRC. Evidence-based preventive and therapeutic agents are still not available for human monkeypox. Further study should be done to explore the role of the smallpox vaccine in preventing human monkeypox.

An Empirical Study on Emergency of Distant Tertiary Education in the Southern Region of Bangladesh during COVID-19: Policy Implication.

Many fields have been affected by COVID-19, including education. The pandemic has prompted a change in education due to the requirement for social distancing. Campuses are now closed in many educational institutions across the globe, and teaching and learning are now conducted online. Internationalization has significantly slowed down. A mixed-method study was designed for this research, with the goal of ascertaining the impact of COVID-19 on Bangladeshi students enrolled in higher education during and after the pandemic. A questionnaire with 19 questions on a Google form was used to collect quantitative data using a 4-point Likert scale and was conducted on 100 students from different universities in the southern part of Bangladesh, such as Barisal University, Patuakhali Science and Technology University, and Bangabandhu Sheikh Mujibur Rahman Science and Technology University. For collecting qualitative data, six quasi-interviews were conducted. A statistical package for Social Science (SPSS) was used to analyze both quantitative and qualitative data. The quantitative results demonstrated that during the COVID-19 pandemic, pupils continuously received teaching and learning. The current study's findings revealed a significant positive correlation between the COVID-19 pandemic and teaching, learning, and student achievement and a significant negative correlation between the COVID-19 pandemic and student goals. The study also revealed that the COVID-19 pandemic had a detrimental effect on students enrolled in higher education programs at the universities. The qualitative judgment showed that students faced many problems when joining classes, such as poor Internet connection and insufficient network and technological facilities, etc. Some students live in rural areas and have slow Internet speeds, which sometimes prevented them from joining class. The findings of the study can help policy makers in higher education to review and adopt a new policy in higher education in Bangladesh. It can also help education instructors in universities to develop a proper study plan for their students.

Impact of Local Vibration Training on Neuromuscular Activity, Muscle Cell, and Muscle Strength: A Review.

This paper presents a review of studies on the effects of local vibration training (LVT) on muscle strength along with the associated changes in neuromuscular and cell dynamic responses. Application of local/direct vibration can significantly change the structural properties of muscle cell and can improve muscle strength. The improvement is largely dependent on vibration parameters such as amplitude and frequency. The results of 20 clinical studies reveal that electromyography (EMG) and maximal voluntary contraction (MVC) vary depending on vibration frequency, and studies using frequencies of 28-30 Hz reported greater increases in muscle activity in terms of EMG (rms) value and MVC data than the studies using higher frequencies. A greater muscle activity can be related to the recruitment of large motor units due to the application of local vibration. A greater increase in EMG (rms) values for biceps and triceps during extension than flexion under LVT suggests that types of muscles and their functions play an important role. Although a number of clinical trials and animal studies have demonstrated positive effects of vibration on muscle, an optimum training protocol has not been established. An attempt is made in this study to investigate the optimal LVT conditions on different muscles through review and analysis of published results in the literature pertaining to the changes in the neuromuscular activity. Directions for future research are discussed with regard to identifying optimal conditions for LVT and better understanding of the mechanisms associated with effects of vibration on muscles.

Role of Reactive Oxygen Species in Aging and Age-Related Diseases: A Review.

Research on the role of reactive oxygen species (ROS) in the aging process has advanced significantly over the last two decades. In light of recent findings, ROS takes part in the aging process of cells along with contributing to various physiological signaling pathways. Antioxidants being cells' natural defense mechanism against ROS-mediated alteration, play an imperative role to maintain intracellular ROS homeostasis. Although the complete understanding of the ROS regulated aging process is yet to be fully comprehended, current insights into various sources of cellular ROS and their correlation with the aging process and age-related diseases are portrayed in this review. In addition, results on the effect of antioxidants on ROS homeostasis and the aging process as well as their advances in clinical trials are also discussed in detail. The future perspective in ROS-antioxidant dynamics on antiaging research is also marshaled to provide future directions for ROS-mediated antiaging research fields.

Formative Research to Design a Child-Friendly Latrine in Bangladesh.

In low- and middle-income countries, most latrines are not accessible to young children. We explored how to modify existing pit latrines to make them child friendly. We conducted four focus group discussions with mothers to explore barriers to child latrine use. We then enrolled 20 households with a child aged 3-7 years old to test six enabling technologies developed based on the identified barriers. Two to three weeks after installing the selected enabling technologies in each household, researchers conducted 19 in-depth interviews with caregivers to explore the technologies' acceptance and feasibility. Common barriers included the discomfort of squatting on a large pan, fear of darkness, and fear of a slippery floor. Of the potential solutions, a ring to stabilize the child while squatting in the latrine was preferred by children and was affordable and available. A wooden board with a smaller hole than the usual pan reduced fears of falling and helped eliminate discomfort but was inconvenient to handle and clean. A transparent fiberglass roof tile was affordable, available, increased visibility, and kept the latrine floor dry. In conclusion, the fiberglass roof tile and stability ring were two affordable and locally available technologies that facilitated latrine use by children aged 3-7 years.

Photoluminescence Enhancement, Blinking Suppression, and Improved Biexciton Quantum Yield of Single Quantum Dots in Zero Mode Waveguides.

The capability of quantum dots to generate both single and multiexcitons can be harnessed for a wide variety of applications, including those that require high optical gain. Here, we use time-correlated photoluminescence (PL) spectroscopy to demonstrate that the isolation of single CdSeTe/ZnS core-shell, nanocrystal quantum dots (QDs) in Zero Mode Waveguides (ZMWs) leads to a significant modification in PL intensity, blinking dynamics, and biexciton behavior. QDs in aluminum ZMWs (AlZMWs) exhibited a 15-fold increase in biexciton emission, indicating a preferential enhancement of the biexciton radiative decay rate as compared to the single exciton rate. The increase in biexciton behavior was accompanied by a decrease in blinking events due to a shortening in the dark state residence time. These results indicate that plasmon mediated enhanced decay rates of QDs in AlZMWs lead to substantial changes in the photophysical properties of single quantum dots, including an increase in biexciton behavior.

Addition of rituximab in relapsed/refractory chronic lymphocytic leukemia after progression on venetoclax monotherapy.

Venetoclax is approved as monotherapy and in combination with rituximab for relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL). Two Phase 1 studies (M12-175 [NCT01328626]; M13-365 [NCT01682616]) were conducted in which patients who initially responded and then progressed on venetoclax monotherapy could receive added rituximab. Ten patients were evaluated (M12-175, n = 8; M13-365, n = 2), and five (50%) responded again upon addition of rituximab, including three complete and two partial responses. Responses were ongoing after 5-10 months of follow-up. Addition of rituximab was well tolerated. These findings indicate potential clinical benefit with rituximab added to venetoclax post-progression in some patients with R/R CLL.

Drivers of Antibiotic Use in Poultry Production in Bangladesh: Dependencies and Dynamics of a Patron-Client Relationship.

Background: There is increasing concern around the use of antibiotics in animal food production and the risk of transmission of antimicrobial resistance within the food chain. In many low and middle-income countries, including Bangladesh, the commercial poultry sector comprises small-scale producers who are dependent on credit from poultry dealers to buy day-old chicks and poultry feed. The same dealers also supply and promote antibiotics. The credit system is reliant upon informal relationships among multiple actors as part of social capital. This paper aims to describe dependencies and relationships between different actors within unregulated broiler poultry production systems to understand the social and contextual determinants of antibiotic use in low-resource settings. Methods: We used a cross-sectional qualitative design including in-depth interviews among purposefully selected commercial poultry farmers (n = 10), poultry dealers (n = 5), sales representatives of livestock pharmaceutical companies (n = 3) and the local government livestock officer as a key-informant (n = 1). We describe the food production cycle and practices relating to credit purchases and sales using social capital theory. Findings: Poultry dealers provide credit and information for small-scale poultry farmers to initiate and operate their business. In return for credit, farmers are obliged to buy poultry feed and medicine from their dealer and sell their market-ready poultry to that same dealer. All farms applied multiple antibiotics to poultry throughout the production cycle, including banned antibiotics such as colistin sulfate. The relationship between dealers and poultry farmers is reciprocal but mostly regulated by the dealers. Dealers were the main influencers of decision-making by farmers, particularly around antibiotic use as an integral part of the production cycle risk management. Our findings suggest that strategies to improve antibiotic stewardship and responsible use should exploit the patron-client relationship which provides the social and information network for small-scale farmers. Conclusion: Social capital theory can be applied to the patron-client relationship observed among poultry farmers and dealers in Bangladesh to identify influences on decision making and antibiotic use. Within unregulated food production systems, strategies to promote the prudent use of antibiotics should target commercial feed producers and livestock pharmaceutical manufacturers as a first step in developing a sustainable poultry value chain.

Advances in Powered Ankle-Foot Prostheses.

We present a review of recent developments in powered ankle-foot prostheses (PAFPs), with emphasis on actuation, high- and low-level control strategies, and pneumatic, hydraulic, and electromechanical actuators. A high-level control strategy based on finite-state machines, combined with low-level control that drives the ankle torque, is the most common control strategy. On the other hand, brushless direct-current motors along with an energy storage and release mechanism are commonly used to reduce the overall size of the actuators and increase PAFP autonomy. Most designs have been evaluated experimentally, showing acceptable results in walking velocity and gait symmetry. Future research must focus on reducing weight, increasing energy efficiency, improving gait phase classification and/or intent of motion-prediction algorithms, updating low-level control of torque and position, and developing the ability of the patient to walk on sloped surfaces and negotiate stairs.

Piloting a low-cost hardware intervention to reduce improper disposal of solid waste in communal toilets in low-income settlements in Dhaka, Bangladesh.

BACKGROUND: Bangladesh faces daunting challenges in addressing the sanitation needs of its urban poor. Maintaining the cleanliness and functionality of communal toilets is dependent upon periodic emptying of fecal sludge, and cooperation between users of communal toilets. Trash disposal into latrines can block the outflow pipes, rendering the toilets non-functional. METHODS: Pre-intervention: We conducted in-depth interviews with five operators of fecal sludge emptying equipment and five adult residents who were also caregivers of children. We identified factors contributing to improper disposal of trash into communal toilets, a barrier to operation of the equipment, in low-income communities of Dhaka, Bangladesh. Intervention design: We developed behavior change communication materials to discourage waste disposal in toilets, and promote use of waste bins. We conducted six focus group discussions with adult male, female, landlord and children to select the preferred design for waste bins to be placed inside toilets, and finalize communication materials. Post-intervention: We then pilot-tested an intervention package to promote appropriate trash disposal practices and thus facilitate periodic removal of fecal sludge when the latrine pits become full. We conducted 20 in-depth interviews and four focus group discussions with community residents, landlords and cleaners of communal toilets. RESULTS: Barriers to appropriate waste disposal included lack of private location for disposal of menstrual hygiene products, limited options for formal trash collection and disposal, and the use of plastic bags for disposing children's feces. A pilot intervention including behavior change communication and trash bins was implemented in two urban slum communities. Spot checks confirmed that the bins were in place and used. Respondents described positive improvements in the appearance of the toilet and surrounding environment. CONCLUSION: The current practice on the part of local residents of disposing of waste into toilets impedes the safe removal of fecal sludge and impairs toilet functionality. Residents reported positive changes in toilet cleanliness and usability resulting from this intervention, and this both improves the user experience with toilets, and also promotes the sustainability of the entrepreneurial model of Vacutug operators supported by WSUP.

Behaviour change intervention to improve shared toilet maintenance and cleanliness in urban slums of Dhaka: a cluster-randomised controlled trial.

OBJECTIVES: Shared toilets in urban slums are often unclean and poorly maintained, discouraging consistent use and thereby limiting impacts on health and quality of life. We developed behaviour change interventions to support shared toilet maintenance and improve user satisfaction. We report the intervention effectiveness on improving shared toilet cleanliness. METHODS: We conducted a cluster-randomised controlled trial among users of 1226 shared toilets in 23 Dhaka slums. We assessed baseline toilet cleanliness in January 2015. The six-month intervention included provision of hardware (bin for solid waste, 4 l flushing bucket, 70 l water reservoir), and behaviour change communication (compound meetings, interpersonal household sessions, signs depicting rules for toilet use). We estimated the adjusted difference in difference (DID) to assess outcomes and accounted for clustering effects using generalised estimating equations. RESULTS: Compared to controls, intervention toilets were more likely to have water available inside toilet cubicles (DID: +4.7%, 95% CI: 0.2, 9.2), access to brush/broom for cleaning (DID: +8.4%, 95% CI: 2, 15) and waste bins (DID: +63%, 95% CI: 59, 66), while less likely to have visible faeces inside the pan (DID: -13%, 95% CI: -19, -5), the smell of faeces (DID: -7.6%, 95% CI: -14, -1.3) and household waste inside the cubicle (DID: -4%, 95% CI: -7, -1). CONCLUSIONS: In one of few efforts to promote shared toilet cleanliness, intervention compounds were significantly more likely to have cleaner toilets after six months. Future research might explore how residents can self-finance toilet maintenance, or employ mass media to reduce per-capita costs of behaviour change.