853 research outputs found
Avoiding inadvertent epidural injection of drugs intended for non-epidural use
Publisher's copy made available with the permission of the publisher © Australian Society of AnaesthetistsInadvertent administration of non-epidural medications into the epidural space has the potential for serious morbidity and mortality. The aim of this study was to collate reported incidents of this type, describe the potential mechanisms of occurrence and identify possible solutions. We searched medical databases and reviewed reference lists of papers retrieved, covering a period of 35 years, regarding this type of medication incident. The 31 reports of 37 cases found is likely to represent a gross underestimation of the actual number of incidents that occur. 'Syringe swap', 'ampoule error', and epidural/intravenous line confusion were the main sources of error in 36/37 cases (97%). Given that no effective treatment for such errors has been identified, prevention should be the main defence strategy. Despite all the precautions that are currently undertaken, accidents will inevitably occur. We have identified areas for systemwide change that may prevent these types of incidents from occurring in future.http://www.aaic.net.au/Article.asp?D=200213
Fatigue: it's relevance to furniture
This paper sets out to present the importance of incorporating fatigue related information into the product engineering of furniture constructions. Contrary to commonly accepted thinking, structural failures in furniture very often result from fatigue associated with its repeated use. Hence, performance testing of furniture is needed not only to determine the ultimate static strength of the furniture but also its fatigue strength
Depression in Collegiate Runners and Soccer Players: Relationships with Serum 25-Hydroxyvitamin D, Ferritin and Fractures
International Journal of Exercise Science 14(5): 1099-1111, 2021. The main purpose of this study was to evaluate relationships between depression versus serum 25-hydroxyvitamin D (vitamin D), serum ferritin (ferritin), and fractures across a competitive season. The authors conducted a prospective observational study (both pre- and post-season testing) on 51 collegiate soccer and cross-country athletes from a Midwest University. Our main outcome measure was depression, measured using the Center for Epidemiological Studies Depression Scale (CES-D). A CES-D score ≥ 16 represented the threshold value for clinical depression. Secondary outcome variables included vitamin D, ferritin, and fractures. Two athletes (3.9%; one female) pre-season while seven athletes (13.7%; five females) post-season demonstrated clinically relevant depression (CES-D score ≥ 16). Depression scores increased from pre- to post-season (6.0 to 8.9; p = 0.009; effect size = 0.53; n = 51). A medium effect noted for depressed athletes vs. non-depressed athletes (n = 7; post-season) to have lower pre-season serum vitamin D (38.4 vs. 50.2 ng/ml; p = 0.15; effect size = 0.68) with a small overall correlation effect (r = -0.08; p = 0.58). A medium correlation effect was noted between post-season ferritin vs. depression scores (r = -0.45; p = 0.01) in the female cohort only. Six athletes (11.8%) sustained fractures and had lower depression scores vs. non-injured athletes (4 vs. 10; p = 0.04; effect size = 1.08) post-season. Depression scores increased over a competitive season, especially in females. Small correlation effects were observed between depression and vitamin D. A medium correlation effect was noted between depression and low ferritin levels, in female athletes only. A large effect was noted between athletes sustaining fractures during the season and depression, post-season, with injured athletes being less depressed than non-injured athletes
Incipient Formation of an Electron Lattice in a Weakly Confined Quantum Wire
We study the low-temperature transport properties of 1D quantum wires as the confinement strength V-conf and the carrier density n(1D) are varied using a combination of split gates and a top gate in GaAs/AlGaAs heterostructures. At intermediate V-conf and n(1D), we observe a jump in conductance to 4e(2)/h, suggesting a double wire. On further reducing n(1D), plateau at 2e(2)/h returns. Our results show beginnings of the formation of an electron lattice in an interacting quasi-1D quantum wire. In the presence of an in-plane magnetic field, mixing of spin-aligned levels of the two wires gives rise to more complex states
A Fault-Tolerant Two-Motor Drive With FCS-MP-Based Flux and Torque Control
Independently controlled multi-motor drives are typically realized by using a common dc link and independent sets of three-phase inverters and motors. In the case of an open-circuit fault in an inverter leg, one motor becomes single-phase. To enable continued controllable operation by eliminating single-phasing, the supply for the motor phase with the faulted inverter leg can be paralleled to a healthy leg of another inverter, using hardware reconfiguration. Hence, the two motors are now supplied from a five-leg inverter, which has inherent voltage and current limitations. Theoretically, violating the voltage limit leads to inverter over-modulation and large torque oscillations. It is shown here that the finite-control-set model predictive control (FCS-MPC), designed to control the machines’ stator flux and torque, can consider the inherent voltage limit dynamically in the control loop. Apart from preserving the independent control of the two machines, the additional constraint consideration significantly widens the operating speed ranges of the machines. In particular, it is shown that whenever the voltage limit is entered, the controller reduces the stator flux level automatically, without requiring external flux reference change. The obtained performance is illustrated using experimental results and is also compared to the conventional two-motor field-oriented control scheme. The control concept is thus fully experimentally verified
Data-Driven Analysis of Engagement in Gamified Learning Environments: A Methodology for Real-Time Measurement of MOOCs
Welfare and economic development is directly dependent on the availability of highly skilled and educated individuals in society. In the UK, higher education is accessed by a large percentage of high school graduates (50% in 2017). Still, in Brazil, a limited number of pupils leaving high schools continue their education (up to 20%). Initial pioneering efforts of universities and companies to support pupils from underprivileged backgrounds, to be able to succeed in being accepted by universities include personalised learning solutions. However, initial findings show that typical distance learning problems occur with the pupil population: isolation, demotivation, and lack of engagement. Thus, researchers and companies proposed gamification. However, gamification design is traditionally exclusively based on theory-driven approaches and usually ignore the data itself. This paper takes a different approach, presenting a large-scale study that analysed, statistically and via machine learning (deep and shallow), the first batch of students trained with a Brazilian gamified intelligent learning software (called CamaleOn), to establish, via a grassroots method based on learning analytics, how gamification elements impact on student engagement. The exercise results in a novel proposal for real-time measurement on Massive Open Online Courses (MOOCs), potentially leading to iterative improvements of student support. It also specifically analyses the engagement patterns of an underserved community
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