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Transparent conducting oxides exhibit giant optical nonlinearities in the near-infrared window where their linear index approaches zero. Despite the magnitude and speed of these nonlinearities, a “killer” optical application for these compounds has yet to be found. Because of the absorptive nature of the typically used intraband transitions, out-of-plane configurations with short optical paths should be considered. In this direction, we propose an alternative frequency-resolved optical gating scheme for the characterization of ultra-fast optical pulses that exploits near-zero-index aluminium zinc oxide thin films. Besides the technological advantages in terms of manufacturability and cost, our system outperforms commercial modules in key metrics, such as operational bandwidth, sensitivity, and robustness. The performance enhancement comes with the additional benefit of simultaneous self-phase-matched second and third harmonic generation. Because of the fundamental importance of novel methodologies to characterise ultra-fast events, our solution could be of fundamental use for numerous research labs and industries.

Aim: Low overhead height can negatively affect chest compression performance. An adapted compression technique has been proposed by paramedic H. Koch (pron. “Cook”). This study compares conventiona...

PURPOSE Patient continuity, described as the student participating in the provision of comprehensive care of patients over time, may offer particular opportunities for student learning. The aim of this study was to describe how students experience patient continuity and what they learn from it. METHOD An interpretive phenomenological study was conducted between 2015 and 2016. Seventeen fourth-year medical students were interviewed following a longitudinal clinical placement and asked to describe their experiences of patient continuity and what they learned from each experience. Transcripts were analyzed by iteratively refining and testing codes, using health system definitions of patient continuity as sensitizing concepts to develop descriptive themes. RESULTS Students described three different forms of patient continuity. Continuity of care, or relational continuity, enabled students to build trusting and professional relationships with their patients. Geographical continuity allowed students to access information about patients from electronic records and their preceptors which allowed students to achieve diagnostic closure and learn to reevaluate their decisions. Students valued the learning that accrued from following challenging patients and addressing challenging decisions over time. Although difficult, these patient continuity experiences led students to critical reflection that was both iterative and deep, leading to intentions for future behavior. CONCLUSIONS Patient continuity in medical education does not depend solely on face-to-face continuity. Within various patient continuity experiences, following challenging patients and experiencing unanticipated diagnostic and management outcomes trigger critical reflection in students, leading to deep learning.

The Backwater reservoir was completed in 1969 and provides water for Dundee and the surrounding area. This paper provides a history of the reservoir including the drivers behind the scheme, construction details and its performance in service, including recent improvement works.

We present research on the development of diode-pumped solid-state lasers suitable for quantum technologies applications at 698.45 nm and 780.24 nm targeting strontium (Sr) and rubidium (Rb) transitions.

OBJECT Mannitol is commonly used to treat elevated intracranial pressure (ICP). The authors analyzed mannitol dosing errors at peripheral hospitals prior to or during transport to tertiary care facilities for intracranial emergencies. They also investigated the appropriateness of mannitol use based on the 2007 Brain Trauma Foundation guidelines for severe traumatic brain injury. METHODS The authors conducted a retrospective review of the Shock Trauma Air Rescue Society (STARS) electronic patient database of helicopter medical evacuations in Alberta, Canada, between 2004 and 2012, limited to patients receiving mannitol before transfer. They extracted data on mannitol administration and patient characteristics, including diagnosis, mechanism, Glasgow Coma Scale score, weight, age, and pupil status. RESULTS A total of 120 patients with an intracranial emergency received a mannitol infusion initiated at a peripheral hospital (median Glasgow Coma Scale score 6; range 3–13). Overall, there was a 22% dosing error rate, which comprised an underdosing rate (< 0.25 g/kg) of 8.3% (10 of 120 patients), an overdosing rate (> 1.5 g/kg) of 7.5% (9 of 120), and a nonbolus administration rate (> 1 hour) of 6.7% (8 of 120). Overall, 72% of patients had a clear indication to receive mannitol as defined by meeting at least one of the following criteria based on Brain Trauma Foundation guidelines: neurological deterioration (11%), severe traumatic brain injury (69%), or pupillary abnormality (25%). CONCLUSIONS Mannitol administration at peripheral hospitals is prone to dosing error. Strategies such as a pretransport checklist may mitigate this risk.

IntroductionPrehospital ultrasound (PHUS) assessments by physicians and non-physicians are performed on medical and trauma patients with increasing frequency. Prehospital ultrasound has been shown to be of benefit by supporting interventions.ProblemWhich patients may benefit from PHUS has not been clearly identified.MethodsA multi-variable logistic regression analysis was performed on a previously created retrospective dataset of five years of physician- and non-physician-performed ultrasound scans in a Canadian critical care Helicopter Emergency Medical Service (HEMS). For separate medical and trauma patient groups, the a-priori outcome assessed was patient characteristics associated with the outcome variable of “PHUS-supported intervention.”ResultsBoth models were assessed (Likelihood Ratio, Score, and Wald) as a good fit. For medical patients, the characteristics of heart rate (HR) and shock index (SI) were found to be most significant for an intervention being supported by PHUS. An extremely low HR was found to be the most significant (OR=15.86 [95% confidence interval (CI), 1.46-171.73]; P=.02). The higher the SI, the more likely that an intervention was supported by PHUS (SI 0.9 toConclusions:In a critical care HEMS, markers of higher patient acuity in both medical and trauma patients were associated with occurrences when an intervention was supported by PHUS. Prospective study with in-hospital follow-up is required to confirm these hypothesis-generating results.O’DochartaighD, DoumaM, AlexiuC, RyanS, MacKenzieM. Utilization criteria for prehospital ultrasound in a Canadian critical care Helicopter Emergency Medical Service: determining who might benefit. Prehosp Disaster Med. 2017;32(5):536–540.

To describe the use of prehospital ultrasonography (PHUS) to support interventions, when used by physician and non-physician air medical crew (AMC), in a Canadian helicopter emergency medical service (HEMS).A retrospective review was conducted of consecutive patients who underwent ultrasound examination during HEMS care from January 1, 2009 through March 10, 2014. An a priori created data form was used to record patient demographics, type of ultrasound scan performed, ultrasound findings, location of scan, type of interventions supported by PHUS, factors that affected PHUS completion, and quality indicator(s). Data analysis was performed through descriptive statistics, Student's t-test for continuous variables, Z-test for proportions, and Mann-Whitney U Test for nonparametric data. Outcomes included interventions supported by PHUS, factors associated with incomplete scans, and quality indicators associated with PHUS use. Differences between physician and AMC groups were also assessed.PHUS was used in 455 missions, 318 by AMC and 137 by physicians. In combined trauma and medical patients, in the AMC group interventions were supported by PHUS in 26% of cases (95% CI 18-34). For transport physicians the percentage support was found to be significantly greater at 45% of cases (95% CI 34-56) p =0.006. Incomplete PHUS scans were common and reasons included patient obesity, lack of time, patient access, and clinical reasons. Quality indicators associated with PHUS were rarely identified.The use of PHUS by both physicians and non-physicians was found to support interventions in select trauma and medical patients. Key words: emergency medical services; aircraft; helicopter; air ambulance; ultrasonography; emergency care, prehospital; prehospital emergency care.

As distributed undergraduate and postgraduate medical education becomes more common, the challenges with the teaching and learning process also increase.To collaboratively engage front line teachers in improving teaching in a distributed medical program.We recently conducted a contest on teaching tips in a provincially distributed medical education program and received entries from faculty and resident teachers.Tips that are helpful for teaching around clinical cases at distributed teaching sites include: ask "what if" questions to maximize clinical teaching opportunities, try the 5-min short snapper, multitask to allow direct observation, create dedicated time for feedback, there are really no stupid questions, and work with heterogeneous group of learners. Tips that are helpful for multi-site classroom teaching include: promote teacher-learner connectivity, optimize the long distance working relationship, use the reality television show model to maximize retention and captivate learners, include less teaching content if possible, tell learners what you are teaching and make it relevant and turn on the technology tap to fill the knowledge gap.Overall, the above-mentioned tips offered by front line teachers can be helpful in distributed medical education.

The industrial take-up of liquid-fill hard capsule technology is limited in part by lack of published long-term physical and chemical stability data which demonstrate the robustness of the system.To assess the effects of extreme long-term storage on liquid-fill capsule product quality and integrity, with respect to both the capsules per se and a standard blister-pack type (foil-film blister).Fourteen sets of stored peroxidation-sensitive liquid-fill hard gelatin capsule product samples, originating ~20 years from the current study, were examined with respect to physical and selected chemical properties, together with microbiological evaluation.All sets retained physical integrity of capsules and blister-packs. Capsules were free of leaks, gelatin cross-linking, and microbiological growth. Eight samples met a limit (anisidine value, 20) commonly used as an index of peroxidation for lipid-based products with shelf lives of 2-3 years. Foil-film blister-packs using PVC or PVC-PVdC as the thermoforming film were well-suited packaging components for the liquid-fill capsule format.The study confirms the long-term physical robustness of the liquid-fill hard capsule format, together with its manufacturing and banding processes. It also indicates that various peroxidation-sensitive products using the capsule format may be maintained satisfactorily over very prolonged storage periods.

IntroductionNon-invasive positive pressure ventilation (NIPPV) is used to treat severe acute respiratory distress. Prehospital NIPPV has been associated with a reduction in both in-hospital mortality and the need for invasive ventilation.Hypothesis/ProblemThe authors of this study examined factors associated with NIPPV failure and evaluated the impact of NIPPV on scene times in a critical care helicopter Emergency Medical Service (HEMS). Non-invasive positive pressure ventilation failure was defined as the need for airway intervention or alternative means of ventilatory support.MethodsA retrospective chart review of consecutive patients where NIPPV was completed in a critical care HEMS was conducted. Factors associated with NIPPV failure in univariate analyses and from published literature were included in a multivariable, logistic regression model.ResultsFrom a total of 44 patients, NIPPV failed in 14 (32%); a Glasgow Coma Scale (GCS) P=.003). Mean scene times were significantly longer in patients who failed NIPPV when compared with patients in whom NIPPV was successful (95 minutes vs 51 minutes; 39.4 minutes longer; 95% CI, 16.2-62.5; P=.001).ConclusionPatients with a decreased level of consciousness were more likely to fail NIPPV. Furthermore, patients who failed NIPPV had significantly longer scene times. The benefits of NIPPV should be balanced against risks of long scene times by HEMS providers. Knowing risk factors of NIPPV failure could assist HEMS providers to make the safest decision for patients on whether to initiate NIPPV or proceed directly to endotracheal intubation prior to transport.LeeJS, O’DochartaighD, MacKenzieM, HudsonD, CouperthwaiteS, Villa-RoelC, RoweBH. Factors associated with failure of non-invasive positive pressure ventilation in a critical care helicopter Emergency Medical Service. Prehosp Disaster Med2015; 30(2): 1–5

The provision of safe drinking water is a global issue, and animal production is recognized as a significant potential origin of human infectious pathogenic microorganisms within source water catchments. On-farm management can be used to mitigate livestock-derived microbial pollution in source water catchments to reduce the risk of contamination to potable water supplies. We applied a modified Before-After Control Impact (BACI) design to test if restricting the access of livestock to direct contact with streams prevented longitudinal increases in the concentrations of faecal indicator bacteria and suspended solids. Significant longitudinal increases in pollutant concentrations were detected between upstream and downstream reaches of the control crossing, whereas such increases were not detected at the treatment crossing. Therefore, while the crossing upgrade was effective in preventing cattle-derived point source pollution by between 112 and 158%, diffuse source pollution to water supplies from livestock is not ameliorated by this intervention alone. Our findings indicate that stream crossings that prevent direct contact between livestock and waterways provide a simple method for reducing pollutant loads in source water catchments, which ultimately minimises the likelihood of pathogenic microorganisms passing through source water catchments and the drinking water supply system. The efficacy of the catchment as a primary barrier to pathogenic risks to drinking water supplies would be improved with the integration of management interventions that minimise direct contact between livestock and waterways, combined with the mitigation of diffuse sources of livestock-derived faecal matter from farmland runoff to the aquatic environment.

Based on a model of spherical Gaussian beam interference, the fringe spacing variations in the measuring volume of a differential LDA system are analysed and the fringe patterns are obtained for different locations of beam waists. It is found that when the incident beams are sharply focused and a large beam cross-angle is used to obtain high spatial resolution, fringe gradients occur along both the x- and z-directions, even though the incident beams intersect at their waists. When the measuring volume is very small, the measurement accuracy of an LDA is limited by inherent fringe gradients mainly along the z-direction. © 1997 Elsevier Science Ltd. All rights reserved.

Background: Virtual worlds provide a promising means of delivering simulations for developing interprofessional health skills. However, developing and implementing a virtual world simulation is a challenging process, in part because of the novelty of virtual worlds as a simulation platform and also because of the degree of collaboration required among technical and subject experts. Thus, it can be difficult to ensure that the simulation is both technically satisfactory and educationally appropriate. Methods: To address this challenge, we propose the use of de Freitas and Oliver’s four-dimensional framework as a means of guiding the development process. We give an overview of the framework and describe how its principles can be applied to the development of virtual world simulations. Results: We present two virtual world simulation pilot projects that adopted this approach, and describe our development experience in these projects. We directly connect this experience to the four-dimensional framework, thus validating the framework’s applicability to the projects and to the context of virtual world simulations in general. Conclusions: We present a series of recommendations for developing virtual world simulations for interprofessional health education. These recommendations are based on the four-dimensional framework and are also informed by our experience with the pilot projects. Keywords: virtual worlds; simulation; interprofessional education; development framework (Published: 16 November 2012) Citation: Med Educ Online 2012, 17 : 11213 - http://dx.doi.org/10.3402/meo.v17i0.11213