Articles Related to TTE

The aim of controlling/regulating cellular processes by surface patterning of biomaterials is a crucial concept in emerging research fields, where the precise fabrication of micro-nano surface topographies is required at manufacturing scales to meet consumer demand. Photolithography is typically employed for surface patterning; however, the high cost, process complexity, and lack of environmentally friendly and sustainable methodologies represent steep barriers for many researchers. Soft lithographic methods have been utilised extensively as a potential alternative for traditional photolithography, yet a photolithographic step is still required for initial template fabrication. Here, we demonstrate the use of repurposed optical consumer items such as DVDs, diffraction glasses, and gratings that would otherwise be thrown away after their useful lives, being used here as a sustainable approach as templates for the formation of complex nano-patterns. By replicating these templates in polydimethylsiloxane (PDMS) and polylactic acid (PLA), we show the varied interactions of human aortic smooth muscle cells (HAoSMC) to these surfaces. Notably, it was demonstrated that, in comparison to nonpatterned substrates, HAoSMC interaction (adhesion, spreading, and viability) was higher on DVD patterned surfaces compared to diffraction glass and grating patterned surfaces according to the results from cell metabolic activity (MTT and Alamar Blue), and proliferation (total DNA) assays. We demonstrate that a simple, reusable, inexpensive, yet robust technology could be a powerful tool in improving our understanding of cell-surface interactions and for the potential development of medical devices with micro- and nanoscale low or high adhesion features

View complete article: PDF  |  Full-text

The use of surface electromyography (sEMG) signals for clinical diagnosis is well appreciated in the medical field. However, the use of sEMG signals for the control of powered prosthetic limbs is still regarded as a futuristic idea. Past and present studies have focused more on the upper limb (hand) as compared to the lower limb (leg). The challenges associated with the controlling leg movement include designing for both balance and locomotion. After amputation, the muscle orientation and alignments on the residual stump changes as some of the anatomical landmarks are changed during surgical procedure. To achieve locomotion, some amputees, generally from third-world nations, use passive mechanical prosthetic limbs with a fixed ankle.

View complete article: PDF  |  Full-text

In the past few years, E-cigarettes (or vaping) are getting the popularity among the youth in Bangladesh. This is critical as it may lead to an increase in the number of smokers in future. The study aimed to identify the trend of E-cigarette smoking, habitual pattern of E-cigarette smokers, and their perception and experiences of health hazards. A cross-sectional mixed methods study was conducted from April to November 2020 in Dhaka and Chittagong cities. A total of 370 E-cigarette smoker aged 18 and above years, were surveyed face-to-face using a semi-structured questionnaire

View complete article: PDF  |  Full-text

Increasing the nickel content in the layered LiNixCoyMnzO2 (x + y + z = 1), the most promising cathode materials for lithium ion batteries (LIBs), has been a dominant strategy to increase their energy density. In this study, we report the control on the primary particle morphology of precursors with different nickel contents, e.g. Ni0.5Co0.2Mn0.3(OH)2 Ni0.6Co0.2Mn0.2(OH)2 and Ni0.8Co0.1Mn0.1(OH)2 by adjusting the preparation process. The scanning electron microscopy (SEM) images demonstrate that by decreasing the pH value and increasing the ammonia concentration, the order of precursors with different nickel contents increases, resulting in gradually directional and orderly stack or interlaced arrangement in the primary particles. With the increase of nickel content, the precursor changes from nano-sheet stacking like plug-in stereoscopic spheres to nano-needle interweaving like wool balls, all of which tend to grow in the direction of [001].

View complete article: PDF  |  Full-text

View complete article: PDF  |  Full-text

Background: Pneumothorax is potentially a life-threatening condition in neonates with little compensatory pulmonary reserve. Hemodynamically significant pneumothorax requires drainage with large-bore chest tubes, and more recently with small-calibre percutaneous pigtail catheters. This study aims to explicate the effectiveness and safety of both the drainage systems exploring ease of insertion, rates of air-leak resolution, recurrence rates as well as potential procedural complications. Methods: This was a retrospective observational audit reviewing medical records of newborns with symptomatic pneumothorax admitted to tertiary neonatal intensive care unit over 4-year duration, and treated with either chest tube or pigtail catheters as the initial treatment approach. Demographic data, details related to pneumothorax, drain related parameters as well as outcome and efficacy parameters were compared among these two methods of intervention. Results: Out of 51 drainage procedures, 27 infants underwent pigtail insertion compared to 24 infants requiring chest tube thoracostomy. Baseline demographic data, time for radiological clearance and resolution of air leak, duration of drain in-situ, recurrence and complication rate, as well as hospitalisation duration were comparable among the two groups. Group of infants who underwent pigtail insertion required significantly less sedation (51.9% vs 83.3%; p=0.021) and invasive ventilation (63% vs 95.8%; p=0.011) than chest tube insertion. Significantly smaller calibre (8.22±1.6Fr vs 9.08±1.44Fr; p<0.05) catheter was required for pneumothorax drainage with pigtail catheter whose insertion was reported to be more operator friendly

View complete article: PDF  |  Full-text

Ruthenium, Antimony and Vanadium doped and undoped tin oxide (SnO2) thin films were prepared by the R.F. Sputtering method. At the beginning of the thin film production studies, pellets were formed by pressing the filled and undoped tin oxide powders in the laboratory environment. The purpose of creating these pellets is to replace commercially purchased target material that acts as the coating material in the sputter coating device. The aim of the study is to use these pellets instead of this commercial target due to its disadvantages such as long lead time and expensiveness, and thus to produce easier, more diverse and high quality thin films. This study includes the synthesis of pure and doped thin films of tin oxide semiconductor material, which has a wide band gap and attracts attention with its wide spread use thanks to this feature, subjecting it to annealing process under different temperatures and times, and structural and morphological characterization studies: XRD, SEM, AFM, XPS, UV-Vis Spectrophotometer and Nano-hardness machine. The study showed that doped and undoped tin oxide films showed similar properties to similar studies seen in the literature, so that the pellets formed in the laboratory environment functioned. No major structural difference was observed in the films produced as a result of the use of pellets and target. As a result of the findings of the study, it has been seen that it is a preliminary study for the investigation of gas sensing properties.

View complete article: PDF  |  Full-text

Due to the ever-increasing importance of studying pollution effects on environment and population, the development of methodologies for the evaluation of atmospheric pollutants has allowed great advances concerning air quality monitoring. Nitrogen dioxide (NO2) and fine particulate matters (PM2.5) have as major sources vehicle engine exhausts and industrial processes. In the municipality of Pelotas, the economical and industrial growth allied to the expansion of the local vehicle fleet have brought several impacts on human health and environment. For this region, there are few studies concerning air pollution monitoring and dispersion. Data were collected seasonally (summer, autumn, winter and spring) in eight points (Porto, Areal, Centro, Fragata, Simões Lopes, Três Vendas, Laranjal,and Capão do Leão) over the city area, aiming to have a picture of the city as a whole. Annual mean ± standard deviation of the PM2.5 measurements are: Porto 48.95±6.28, Areal 3.29±4.56, Centro 39.56±7.05, Fragata 30.28±3.59,Simões Lopes9.5±.9, Três Vendas 3.4±3.80, Laranjal 29.79±2.34, Capão do Leão 24.25±3.2 and annual mean ±standard deviation for NO2 were: Porto 9.06±.5, Areal 0.49±0.94, Centro 4.3±0.89, Fragata 2.44±0.56, Trem 7.20±0.99, Três Vendas 2.94±.22, Laranjal 8.83±.97, Capão do Leão 6.77±0.76. We conclude that there are significant differences in different places of the city, mainly due to traffic and human activities characteristics of each point. On the other hand, meteorological factors act similarly in all sites concerning the pollution dispersion.

View complete article: PDF  |  Full-text

In this work, an original method is proposed and used for measurement of the optical depth of a self-reversed spectral line. A theoretical approach is utilized in an in homogenous laser induced plasma at local thermodynamic to simulate self-reversed line and then to get the main line profile without self-absorption. In this research, the spatial and temporal evolution of optical depth of two spectral lines of Ca II at 393.4 nm and 396,9 nm is studied. Furthermore, the variation of optical depth versus the concentration of species emitter inside of plasma plume is investigated. In addition, the validity of this method is affirmed during comparison with results obtained by other techniques.

View complete article: PDF  |  Full-text

A dental chair and its environment can be contaminated with droplet/splatter and aerosol particles, which contain various pathogens, including SARS-Cov-2, that can be transmitted by contact or inhalation. We aimed to evaluate the maximal distance of droplet/splatter projections for four different air and water-cooled dental instruments using a patient simulator, to define the boundaries of the open-plan area contaminated immediately after treatment. We used a dental chair unit placed in a room in the open-plan area. Fluorescent powder was added to water, to know the maximal distance reached by the droplet/splatter on the surfaces of the dental room covered with white sheets. Dental care was performed in an artificial mouth using either an air turbine handpiece, a high-speed electric contra-angle, an ultrasonic scaler, or an air/powder polisher with a constant volume of colored water. Maximal distances of droplet/splatter projections were measured after identifying the fluorescent patterns on the surfaces. Calculated heights and angles were then used after normalization to know the maximal distance that could be reached by these projections. In these conditions, the theoretical maximal distance of droplet/splatter projection was 295 cm for the air-powder polisher, followed by 238 cm for the high-speed electric contra-angle, 93 cm for the air turbine and 77 cm for the ultrasonic scaler. Theoretical projections for the ultrasonic scaler did not go beyond the dental room. In our open-plan area, droplet/splatter projections can extend beyond the dental room entrance, but not over 1.80 m-high partitions, and could contaminate areas located nearby. Simple preventive measures would be to limit the perimeter of these projections, for example by installing a door, in addition to measures to limit the scope of aerosols.

View complete article: PDF  |  Full-text

Driving pattern of the given vehicle in a city is represented by the driving cycle which is used by modal models for estimation of vehicular emissions. In this study, a driving cycle was developed for passenger cars in the city of Islamabad. A representative route for city was identified which included parts of highway, arteries, and streets. Speed-time data was collected along the selected route in both peak and off-peak hours. The on-board measurement method was adopted for data collection on highways, whereas on arteritis and streets, chase car method has opted for data collection. The developed cycle showed comparable values of average speed and acceleration with New European Driving Cycle (NEDC), but acceleration and deceleration were observed to be lower. The emission estimation and fuel consumption were calculated by the Comprehensive Modal Emission Model (CMEM) for 4 selected vehicle types. The average emissions for the selected vehicles were 204.4 g CO2/km, 2.3 g CO /km, 0.09 g HCs /km, 0.31 g NOx /km emitted, and 65.7 g of fuel consumed /km. The developed cycle showed higher fuel consumption and CO2 emissions /km traveled than NEDC for all 4 passenger car types. However, HCs, CO, and NOx emissions were lower. The developed driving cycle can be used for estimation of the emissions from passenger cars in the city and this information can be useful for future emission projections and policy making.

View complete article: PDF  |  Full-text

Particulate matter (PM) concentrations are significantly higher in urban railway tunnels (178.1 μg/m3) than in metropolitan areas (49 μg/m3). Nitrogen oxide (NOx) concentrations, which are a direct cause of lung disease, have been found to exceed the atmospheric standard of the Ministry of Environment in tunnels in Korea. Dust generated by trains is scattered at high speed along tunnels, making filtration difficult. The development of filters that can be used in tunnels is urgently required. In this study, the results of using an activated carbon filter (ACF) were analyzed and compared with the laboratory-scale PM adsorption using functional activated carbon non-woven fabric filters (Cerebasel, Cerecore) that can be manufactured in Korea. The fine PM concentration, filter depth, and flow rate in the tunnel were the experimental variables. We compared PM concentrations before and after the filter experiments, and calculated the PM removal efficiency to determine the optimal conditions.

View complete article: PDF  |  Full-text

The aim of this research was to assess the biochar ability to protect the photosynthesis process face to Cd contamination, especially, when nitrogen fertilizer was added at adequate amount. Culture of tomato seedlings was conducted on pots containing soil added with different portion of biochar (0, 3.5 and 7%) and nitrogen (3 or 6g NH4NO3). Irrigation was done by water (control condition) or Cd solution (150µM). Data showed that regardless presence of Cd, synchronously addition of high nitrogen fertilizer (6g) and biochar (7%) in the culture medium resulted in fresh matter production, photosynthetic pigment (Chlorophyll a) and mineral elements content enhancement. Similar observation was shown concerning the mineral nutrition (nitrogen, phosphorus and potassium contents).

View complete article: PDF  |  Full-text

There is a proliferation of particulate matter in the atmosphere within and around the cities because of increased industrial activities. It is thus hypothesized that increase in human activities lead to increase in pollutants concentration inside (n=80 houses sampled) and outside residential areas. Thus, to investigate the air quality at different residential areas within indoor and outdoor environment air samples were collected using Particle Counter (Model: HHPC MET), and Gas Monitor (Aeroqual series 500) to determine particulate matters (i.e., PM10, and PM2,5), volatile organic carbon (VOC) and total solid particle (TSP).

View complete article: PDF  |  Full-text

Artificial light at night has been reported to have significant effects on the physiology and behaviour of animals by its impact on their circadian rhythm. This study investigated the effect of artificial light spectra at night on neurotransmitter activities and neurobehavioural changes in the albino rat. Blue (470 nm) and red (665 nm) lights were used; with ambient light and darkness serving as positive and negative controls, respectively. The rats were exposed to daylight from 6 am to 6 pm and 12 hours of artificial light (6 pm - 6 am) daily (light sources were 13 Watt compact florescent electric bulbs). Neurobehavioural outcomes were measured using the Open Field Test (OFT) and Morris Water Maze (MWM).

View complete article: PDF  |  Full-text

The anodization of aluminum foils having micrometer thickness is a common process and results in hexagonally self-ordered alumina membranes. However, anodic aluminum oxide (AAO) membranes fabricated from nanometer-thin films present new challenges to the anodization process, since aluminum films adheres poorly on supporting substrates and the smoothness of the film is highly related to the kind of substrate.

View complete article: PDF  |  Full-text

Anodisation of pure titanium has been carried out in sulphuric and in phosphoric acid solutions at potentials ranging from 50 to 150V. The SEM and AFM morphological analysis indicates that, within this potential range, oxidation in sulphuric acid solution produces better developed mesoporous oxide layers.

View complete article: PDF  |  Full-text