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Online learning has become an increasingly expected and popular component for education of the modern-day adult learner, including the medical provider. In light of the recent coronavirus pandemic, there has never been more urgency to establish opportunities for supplemental online learning. Heart University aims to be ‘the go-to online resource’ for e-learning in congenital heart disease and paediatric acquired heart disease. It is a carefully-curated open access library of pedagogical material for all providers of care to children and adults with congenital heart disease or children with acquired heart disease, whether a trainee or a practicing provider. In this manuscript, we review the aims, development, current offerings and standing, and future goals of Heart University.
Disorders of voice can limit an individual's participation and impair social interaction, thus affecting overall quality of life. Perceptual and objective evaluations can provide the clinician with detailed information regarding voice disorders.
This study comprised 40 subjects aged 34–46 years, 20 of whom (10 male, 10 female) had unilateral vocal fold palsy. Data were obtained for all participants from: the Voice Handicap Index, the grade, roughness, breathiness, asthenia and strain (‘GRBAS’) scale, acoustic voice analysis, electroglottography, and voice range profiles.
The voice evaluations revealed statistically significant (p < 0.05) differences between the controls and study group, both in males and females, pre- and post-therapy.
Despite the normalisation of vocal parameters, acoustic, perceptual and self-rated assessments revealed statistically significant differences after therapy. Hence, acoustic measures, namely electroglottographic perturbation, and voice frequency and intensity range, are recommended prior to termination of therapy.
Preoperative mechanical ventilation is associated with morbidity and mortality following CHD surgery, but prior studies lack a comprehensive analysis of how preoperative respiratory support mode and timing affects outcomes.
We retrospectively collected data on children <18 years of age undergoing cardiac surgery at an academic tertiary care medical centre. Using multivariable regression, we examined the association between modes of preoperative respiratory support (nasal cannula, high-flow nasal cannula/noninvasive ventilation, or invasive mechanical ventilation), escalation of preoperative respiratory support, and invasive mechanical ventilation on the day of surgery for three outcomes: operative mortality, postoperative length of stay, and postoperative complications. We repeated our analysis in a subcohort of neonates.
A total of 701 children underwent 800 surgical procedures, and 40% received preoperative respiratory support. Among neonates, 243 patients underwent 253 surgical procedures, and 79% received preoperative respiratory support. In multivariable analysis, all modes of preoperative respiratory support, escalation in preoperative respiratory support, and invasive mechanical ventilation on the day of surgery were associated with increased odds of prolonged length of stay in children and neonates. Children (odds ratio = 3.69, 95% CI 1.2–11.4) and neonates (odds ratio = 8.97, 95% CI 1.31–61.14) on high-flow nasal cannula/noninvasive ventilation had increased odds of operative mortality compared to those on room air.
Preoperative respiratory support is associated with prolonged length of stay and mortality following CHD surgery. Knowing how preoperative respiratory support affects outcomes may help guide surgical timing, inform prognostic conversations, and improve risk stratification models.
In this paper, longitudinal and lateral-directional aerodynamic characterisation of the Cropped Delta Reflex Wing (CDRW) configuration–based unmanned aerial vehicle is carried out by means of full-scale static wind-tunnel tests followed by full-scale flight testing. A predecided set of longitudinal and lateral/directional manoeuvres is performed to acquire the respective flight data, using a dedicated onboard flight data acquisition system. The compatibility of the acquired dynamics is quantified, in terms of scale factors and biases of the measured variables, using Kinematic consistency check. Maximum likelihood (ML), least squares and newly emerging neural Gauss–Newton (NGN) methods were implemented for a wing-alone delta configuration, mainly to capture the dynamic derivatives for both longitudinal and lateral directional cases. Estimated damping and weak dynamic derivatives, which are in general challenging to capture for a wing alone configuration, are consistent using ML and NGN methods. Validation of the estimated parameters with aerodynamic model is performed by proof-of-match exercise and are presented therein.
In this perspective, the authors challenge the status quo of polymer innovation. The authors first explore how research in polymer design is conducted today, which is both time consuming and unable to capture the multi-scale complexities of polymers. The authors discuss strategies that could be employed in bringing together machine learning, data curation, high-throughput experimentation, and simulations, to build a system that can accurately predict polymer properties from their descriptors and enable inverse design that is capable of designing polymers based on desired properties.
Introduction: Abdominal pain is one of the most frequent reasons for an emergency department (ED) visit. Most cases are functional and no therapy has proven effective. Our objective was to determine if hyoscine butylbromide (HBB) (BuscopanTM) is effective for children who present to the ED with functional abdominal pain. Methods: We conducted a randomized, blinded, superiority trial comparing HBB 10 mg plus acetaminophen placebo to oral acetaminophen 15 mg/kg (max 975 mg) plus HBB placebo using a double-dummy approach. We included children 8-17 years presenting to the ED at London Health Sciences Centre with colicky abdominal pain rated >40 mm on a 100 mm visual analog scale (VAS). The primary outcome was VAS pain score at 80 minutes post-administration. Secondary outcomes included adverse effects; caregiver satisfaction with pain management using a five-item Likert scale; recidivism and missed surgical diagnoses within 24-hours of discharge. Analysis was based on intention to treat. Results: We analyzed 225 participants (112 acetaminophen; 113 HBB). The mean (SD) age was 12.4 (3.0) years and 148/225 (65.8%) were females. Prior to enrollment, the median (IQR) duration of pain prior was 2 (4.5) hours and analgesia was provided to 101/225 (44.9%) of participants. The mean (SD) pre-intervention pain scores in the acetaminophen and HBB groups were 62.7 (15.9) mm and 60.3 (17.3) mm, respectively. At 80 minutes, the mean (SD) pain scores in the acetaminophen and HBB groups were 30.1 (28.8) mm and 29.4 (26.4) mm, respectively and there were no significant differences adjusting for pre-intervention scores (p = 0.96). The median (IQR) caregiver satisfaction was high in the acetaminophen [5 (2)] and HBB [5 (1)] groups (p = 0.79). The median (IQR) length of stay between acetaminophen [235 (101)] and HBB [234 (103)] was not significantly different (p = 0.53). The proportion of participants with a return visit for abdominal pain was 4/112 (3.5%) in the acetaminophen group and 6/113 (5.3%) in the HBB group. The most common adverse effect was nausea (9% in each group) and there were no significant differences in adverse effects between acetaminophen (26/112, 23.2%) and HBB (31/113, 27.4%) (p = 0.52). There were no missed surgical diagnoses. Conclusion: For children with presumed functional abdominal pain who present to the ED, both acetaminophen and HBB produce a clinically important (VAS < 30 mm) reduction in pain and should be routinely considered in this clinical setting.
The present article deals with the influence of the induced magnetic field on an unsteady two dimensional incompressible free convective chemically reacting slip flow of Jeffrey fluid between two parallel plates under the influence of the thermal radiation, Soret and Dufour. It is assumed that the flow is generated due to periodic suction/injection and the non-uniform temperature and concentrations are varying periodically with time at the plates. The governing partial differential equations are reduced into nonlinear ordinary differential equations by using similarity transformations and solved by shooting method along with Rung-Kutta 4th order scheme. The results are analyzed for various flows, heat and mass transfer characteristics with respect to various prominent parameters such as the ratio of relaxation to retardation times, Deborah number, magnetic Reynold’s number, Strommer’s number, radiation parameter, chemical reaction parameter, Soret and Dufour numbers in details through graphs and tables. It is observed that the temperature of the fluid is enhanced with Soret and Dufour whereas the concentration is decreased. Also the mass transfer rate of the fluid is enhanced with Strommer’s number, whereas the heat transfer rate decreases with increasing of the Jeffery fluid parameter. The present results have good agreement with published work for Newtonian case.
Nano-structured thin films have a variety of applications from waveguides, gaseous sensors to piezoelectric devices. Grazing Incidence Small Angle x-ray Scattering images enable classification of such materials. One challenge is to determine structure information from scattering patterns alone. This paper highlights the design of multiple Convolutional Neural Networks (CNN) to classify nanoparticle orientation in a thin film by learning scattering patterns. The network was trained on several thin films with a success rate of 94%. We demonstrate CNN robustness under different noises as well as demonstrate the potential of our proposed approach as a strategy to decrease scattering pattern analysis time.
In this paper, two different radiating structures fed with modified L-probe, are reported using a circuit theory concept. The proposed antennas are operating in wireless local area network (WLAN) and universal mobile telecommunications system (UMTS) frequency bands. In the first design, an E-shaped patch is studied to increase the bandwidth. It is observed that the bandwidth is directly proportional to notch dimensions. In the second design, E-shaped patch is modified to reduce the antenna size up to 30% with high bandwidth. In the first design, measured bandwidth and gain achieved are 32.68% (1.92–2.67 GHz) and 8.43 dBi while in second design it is 34.19% (1.94–2.74 GHz) and 8.39 dBi, respectively. Radiation patterns for both the antennas are symmetrical and broadside in nature. The proposed antennas are fabricated and measured results compare well with the theoretical and simulated results.
Stereotactic body radiotherapy (SBRT) is widely used for the treatment of stage-I non-small cell lung cancer (NSCLC). Patient-specific motion correlated with 4DCT could be essential for hypofractionated SBRT. All patients undergoing SBRT do not require motion management during the dose delivery. The objective of this study was to evaluate which patient may benefit from Gated SBRT.
Materials and methods
Treatment planning of 20 patients of stage-I NSCLC was analysed. Conventional and 4DCT scans were taken. Internal target volume as well as planning target volume (ITV and PTV) were determined in the CT data sets. PTVall phases created using 4DCT data sets and PTV15mm created using conventional CT data were compared. Also, ITVall phases were compared with ITV created from maximum intensity projections (ITVMIP). Suitability of patients for motion management-based treatment delivery was also evaluated.
The average ITVMIP to ITVall phases ratio is 1·06 indicating good agreement between them. Based on the ratio of intensity projections, 9 out of 17 patients were found suitable for our existing gated treatment.
4D CT is the main requirement in SBRT to identify the patients who can benefit from motion management during the dose delivery.
Grewia tenax locally known as ‘Gangerun’, is an important multipurpose underutilized shrub and potentially threaten species of the Thar Desert of India. Owing to its importance, naturally available germplasm was collected and evaluated for its sustainable utilization in future. Data on individual mother plant, seed characters and soil profile were investigated. Habitat occurrence of G. tenax was found in patches with dominant association of Euphorbia caducifolia across the four districts of western Rajasthan. Individual plant on unprotected area portrayed far lower average height (0.95 m) and canopy area (1.75 m2) than protected area (2.63 m and 13.89 m2) signifying level of browsing pressure on this species in Jaisalmer. Soil samples belonging to Pali region have high organic carbon and low electrical conductivity content than Jaisalmer and Jodhpur. The statistical analysis of seed characters revealed the presence of high coefficient of variation (%) in 100-seed weight (HSW; 27.36) followed by seed length (SL; 8.06) and least in seed breadth (SB; 5.85). The range and mean values of HSW, SL, SB and length:breadth ratio (LBR) were (2.02–7.00 and 3.34 g), (4.36–6.15 and 5.36 mm), (3.73–4.68 and 4.25 mm) and (1.11–1.44 and 1.27), respectively. Significantly positive correlation was observed between SL and LBR (0.73) followed by HSW and SL (0.66). Along with these findings, its economic importance, utilization and conservation are detailed in this paper as to hasten further research on its various aspects for its successful conservation and utilization.
Engineers are required to provide economically feasible solutions to existing problems. To achieve this, engineers must possess knowledge of economy to evaluate the monetary consequences of the products, projects and processes that they design. Engineering design solutions do not exist in a vacuum but within the context of a business opportunity. Since almost every problem has multiple solutions, so the issue is: how does one rationally select a design with the most favorable economic result? The answer to this question is provided by engineering economy. Engineering economy, the analysis of the economic consequences of engineering decisions, is said to have originated in A. M. Wellington's The Economic Theory of Railway Location, published in 1887. Engineering economy is now considered a part of the education of every engineer, as it provides a systematic framework for evaluating the economic aspects of competing design solutions. Just as engineers model the effect of temperature on cutting tools or the thermodynamic response of an air compressor, they must also model the economic impact of their recommendations. What is ‘engineering economy’ and why is it so important? The initial reaction of many engineering students to this question is, ‘money matters will be handled by someone else and I need not worry about these matters’. In reality, any engineering project must be, not only physically realizable but also economically affordable. Understanding and applying economic principles to engineering have never been more important. Engineering is more than a problem-solving activity focusing on the development of products, systems, and processes to satisfy a need or demand. Beyond function and performance, solutions must also be economically viable. Design decisions affect limited resources such as time, material, labor, capital and natural resources, not only initially i.e. during conceptual design but also through the remaining phases of the life cycle i.e. during detailed design, manufacture and distribution, service, retirement and disposal. Engineers should realize that the solution provided by them does not make sense and will not be acceptable, if it is not profitable.
Engineering or business projects require huge capital investments. Economy studies are necessary to be conducted to establish whether a proposed capital investment and its associated expenditures can be recovered over time in addition to a return on the capital that is attractive in view of risks involved and opportunity costs of the limited funds. The concepts of interest and money-time relationships of Chapter 4 are quite useful in arriving at the investment decision.
Since different projects involve different patterns of capital investment, revenue or savings cash flows and expenditure or disbursement cash flows, no single method is perfect for making economy studies of all types of projects. As a result, several methods for making economy studies are commonly used in practice. All methods will produce equally satisfactory results and will lead to the same decision, provided the inherent assumptions of each method are enforced.
This chapter explains the working mechanism of six basic methods for making economy studies and also describes the assumptions and interrelationships of these methods. In making economy studies of the proposed project, the appropriate interest rate to be used for discounting purpose is taken to be equal to the minimum attractive rate of return (M.A.R.R.) expected by the fund provider. The value of M.A.R.R. is established in view of the opportunity cost of capital which reflects the return forgone as it is invested in one particular project.
The following six methods are commonly used for making economy studies:
1. Present worth (P.W.)
2. Future worth (F.W.)
3. Annual worth (A.W.)
Rate of return:
1. Internal rate of return (I.R.R.)
2. External rate of return (E.R.R.)
3. Explicit reinvestment rate of return (E.R.R.R.)
PRESENT WORTH(P.W.) METHOD
In this method, equivalent worth of all cash flows relative to some point in time called present worth i.e. P.W. is computed. All cash inflows and outflows are discounted to the present point in time at an interest rate that is generally M.A.R.R. using appropriate interest factor. The following steps are used to calculate P.W.:
Step 1: Draw the cash flow diagram for the given problem.
Step 2: Determine the P.W. of the given series of cash receipts by discounting these future amounts to the present at an interest rate i equal to M.A.R.R.