Brain machine interfaces (BMIs), or brain computer interfaces (BCIs), are devices that act as a medium for communications between the brain and the computer. It is an emerging field with numerous ...applications in domains of prosthetic devices, robotics, communication technology, gaming, education, and security. It is noted in such a multidisciplinary field, many reviews have surveyed on various focused subfields of interest, such as neural signaling, microelectrode fabrication, and signal classification algorithms. A unified review is lacking to cover and link all the relevant areas in this field. Herein, this review intends to connect on the relevant areas that circumscribe BMIs to present a unified script that may help enhance our understanding of BMIs. Specifically, this article discusses signal generation within the cortex, signal acquisition using invasive, non-invasive, or hybrid techniques, and the signal processing domain. The latest development is surveyed in this field, particularly in the last decade, with discussions regarding the challenges and possible solutions to allow swift disruption of BMI products in the commercial market.
In this study, zeolitic imidazolate framework (ZIF-67) derived nano-porous carbon structures that were further hybridized with MnO2 were tested for oxygen reduction reaction (ORR) as cathode material ...for fuel cells. The prepared electrocatalyst was characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and Energy Dispersive X-ray Analysis (EDX). Cyclic voltammetry was performed on these materials at different scan rates under dissolved oxygen in basic media (0.1 M KOH), inert and oxygen rich conditions to obtain their I–V curves. Electrochemical impedance spectroscopy (EIS) and Chronoamperometry was also performed to observe the materials’ impedance and stability. We report improved performance of hybridized catalyst for ORR based on cyclic voltammetry and EIS results, which show that it can be a potential candidate for fuel cell applications.
Brick manufacturing sector is a major contributor to air pollution and greenhouse gas emissions in South Asian countries. This study investigates barriers and drivers relevant to the adoption of ...cleaner zig-zag kiln (ZZK) technology in Punjab, Pakistan by surveying 63 kiln owners. These survey respondents owned three different types of brick kiln i.e., ZZK, Fixed chimney bull’s trench kiln (FCBTK), and clamp type kiln (CTK). Roger’s model of innovation diffusion was adopted to access the determinants pertaining to relative advantage, compatibility, complexity, trialability and observability. Survey questionnaire included questions related to 35 factors (20 drivers and 15 barriers) and responses were recorded on Likert scale. These barrier and drivers covered variety of factors associated with regulatory, financial, technological, social, and environmental issues that may influence the perception and decision of kiln owners for the adoption of cleaner ZZK technology. Our results show that most important drivers pertain to economic benefits such as emissions fine reduction, decrease in fuel costs and year-round operations. Other high impact drivers relate to compatibility and similarity between ZZK and FCBTK construction and operations. Top-ranked barriers highlight the challenges associated with financial burden of retrofitting cost, higher salaries demanded by skilled workers, and maintenance issues for blower assembly. Mean scores for the determinants pertaining to the attributes of Roger’s model were computed. Our results show that both relative advantage and compatibility received highest mean scores. On the other hand, trialability and observability received lowest scores. Government, policy makers and other relevant stakeholders should focus on awareness campaigns, capacity building and training of labor, and developing financial instruments to provide loans to kiln owners for covering retrofit costs.
Diphtheroids are gram-positive pleomorphic bacilli in the family of Coryneform bacteria. These organisms are present as part of the human flora. Past practice habits had been to consider them as ...contaminants when isolated from clinical samples. Corynebacterium jeikeium is one of the most clinically important nondiphtherial Corynebacteria that can cause different forms of infections specifically in patients with underlying risk factors and co-morbidities including immunocompromised subjects. Through this article, we present a 67-year-old gentleman with extensive co-morbidities including heart failure with reduced ejection fraction and ESRD on hemodialysis through a femoral catheter who presented with chest pain and fatigue. Further investigation confirmed diagnosis of C. jeikeium endocarditis. We go on to review previously reported cases of C. jeikeium endocarditis and we will discuss different aspects of C. jeikeium infection with a focus on microbiology, pathophysiology, and treatment.
This paper provides a review about the major work done on helical baffles to improve the performance of shell and tube heat exchangers. Some of the major factors affecting the performance of shell ...and tube heat exchanger are discussed. A comparison between segmental baffles and helical baffles is also presented to show that helical baffles are more advantageous than segmental baffles. In most cases, discontinuous, folded, sextant helical baffles, 40° baffle inclination angle as well as low baffle spacing will give the best results when integrated in some combination, whereas continuous helical baffles eliminate dead regions. Moreover, sealing strips are more likely to improve the performance of shell and tube heat exchangers with continuous helical baffles.
Objective:
To assess the impact of intermediate-term treatment with rosiglitazone on high-sensitivity cardiac troponin T levels among patients with type 2 diabetes mellitus with or at high risk of ...coronary artery disease.
Methods:
High-sensitivity cardiac troponin T level was measured at baseline and after 6 months of study treatment in a randomized trial comparing rosiglitazone versus placebo in patients with type 2 diabetes and prevalent cardiovascular disease or multiple cardiovascular disease risk factors. Univariable and multivariable linear regression analyses were performed to assess the effect of rosiglitazone versus placebo on high-sensitivity cardiac troponin T levels.
Results:
The study included 150 randomized participants, of whom 106 had paired baseline and end-of-study blood samples for analysis (mean age: 56 ± 8 years, 42% women; 8.8 years average type 2 diabetes duration; mean haemoglobin A1c of 7.5). Almost all study participants (93%) had detectable high-sensitivity cardiac troponin T (⩾3 ng/L) at baseline, including 23% with high-sensitivity cardiac troponin T levels exceeding the threshold commonly used to diagnose myocardial infarction (⩾14 ng/L). Change in high-sensitivity cardiac troponin T levels from baseline to follow-up was not significantly different between rosiglitazone and placebo groups (p = 0.316).
Conclusion:
Rosiglitazone did not impact high-sensitivity cardiac troponin T levels, adding to the growing body of literature suggesting that the incremental heart failure risk associated with rosiglitazone is not mediated by direct myocardial injury.
Experimental data driven calibration and reactor sensitivity analysis is a feasible route toward efficient and sustainable CO2 utilization. A feasible approach was developed and implemented to model ...and simulate the direct conversion of CO2 and H2 to methanol through the direct utilization of experimental data. This approach is widely applicable to any reaction and reactor type. Monolithic reactors, showing lower mass transfer resistance than conventional packed bed reactors, were chosen specifically in this study. This novel technique allows for expedited calibration of experimentally acquired lab data into kinetic, equilibrium, and adsorption parameters for a wide variety of reactions. Such a technique was used in this paper to generate a monolithic reactor model. Simulations based on the generated model were used to study internal and external mass transport in the monolithic reactor. Catalyst layer simulation showed no diffusion limitation between 100 and 300 °C while the external mass transfer coefficient of 0.25 m·s–1 signifies reasonably low external mass transfer resistance. Sensitivity analysis show that circular channel shape offers the highest average Sherwood number (Sh = 6.27 @ 300 °C) while a triangular channel shape provides the highest surface area (SA = 45.6 mm2) at constant volume among other channel shapes with constant cross-sectional area, wall thickness, and channel length. Moreover, a channel hydraulic diameter of 0.4 mm with a channel length of 5 cm was found to be the most optimal for this type of reactor. Lastly, the fine-tuned channel shape and channel length provided the best velocity gradient and residence time for high yield.
Abstract Objectives In this study, the authors performed a meta-analysis of currently available comparative prospective studies to assess the efficacy and safety of exercise training in heart failure ...(HF) patients with implantable cardioverter-defibrillators (ICD). Background ICDs have been shown to improve survival in patients with HF. However, many patients with ICDs experience fear of shocks and avoid physical activity. Few data exist for efficacy and safety of exercise training in HF patients with ICDs. Methods Prospective parallel arm trials with control and exercise training groups that evaluated the efficacy of exercise training in patients with ICDs were included in the meta-analysis. Outcomes of interest were difference in the change in cardiorespiratory fitness (CRF) (ml/kg per min) between exercise and control group and the likelihood of ICD shocks among exercise training compared with that among control participants on follow-up. Results We included study level data from 6 trials (5 randomized controlled trials and 1 nonrandomized controlled trial). In the pooled analysis, ICD patients undergoing exercise training had significant improvement in CRF (weighted mean difference: 1.98 ml/kg/min; 95% confidence interval CI: 0.58 to 3.38). The likelihood of ICD shocks on follow-up was also significantly lower among exercise training than among control participants (pooled odds ratio: 0.47; 95% CI: 0.24 to 0.91). Conclusions Among patients with HF and ICD implantation, exercise training was associated with significant improvement in CRF and lower likelihood of ICD shocks.
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