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Background There is a need for improvement in informed medical consent to address the lack of standardization and to increase patient engagement. Objective To investigate the use of a video to aid informed consent for Mohs micrographic surgery and evaluate patient understanding, satisfaction, anxiety, and time savings relative to verbal consent. Methods A 2-armed randomized controlled trial involving 102 patients compared video-assisted consent with a control group who underwent consent in the standard verbal manner. All participants underwent questionnaire-based testing of knowledge, satisfaction, and anxiety, and the time of each consultation was measured. Results Patients who watched the video performed significantly better in the knowledge questionnaire compared with the control group (P = .02), were more satisfied with their understanding of the risks of Mohs micrographic surgery (P = .013), and spent less time with their physician (P = .008). Additionally, 78.4% of video group patients reported that they preferred seeing the video before speaking with their physician. Limitations The study design may not replicate day-to-day clinical practice. Conclusion Video-assisted consent for Mohs micrographic surgery improves patient knowledge, leads to a better understanding of the risks, and saves physicians time without compromising patient satisfaction and anxiety levels in this study setting.

BACKGROUND As the availability of Mohs micrographic surgery (MMS) continues to expand in Australia and incidence of keratinocyte cancer increases in adolescents and young adults, there has been rising interest in the use of MMS in this population. OBJECTIVE This study aimed to evaluate the characteristics of MMS cases in patients younger than 40 years. METHODS A review was performed of all MMS cases in patients younger than 40 years at the time of their surgery from 2012 to 2017 at the Skin and Cancer Foundation Australia, with comparison to a control group, aged older than 40 years. Patient, tumor and management characteristics were analyzed. RESULTS Four hundred ninety-three cases were eligible. Study and control groups differed significantly regarding gender (p < .001), tumor pathology (p < .001), anatomic site of tumor (p < .001), Mohs surgery stages (p = .039), defect size (p < .001), and repair method (p < .001). LIMITATIONS Retrospective study at a single institution. CONCLUSION Mohs micrographic surgery cases in patients younger than 40 years exhibit unique patient and tumor characteristics influencing choice of repair method.

One of the key challenges for the electric vehicle industry is to develop high-power-density electric motors. Achieving higher power density requires efficient heat removal from inside the motor. In order to improve thermal management, a multiphysics modeling framework that is able to accurately predict the behavior of the motor, while being computationally efficient, is essential. This paper first presents a detailed validation of a lumped parameter thermal network (LPTN) model of an Internal Permanent Magnet synchronous motor within the commercially available motor-cad modeling environment. The validation is based on temperature comparison with experimental data and with more detailed finite element analysis (FEA). All critical input parameters of the LPTN are considered in detail for each layer of the stator, especially the contact resistances between the impregnation, liner, laminations, and housing. Finally, a sensitivity analysis for each of the critical input parameters is provided. A maximum difference of 4%—for the highest temperature in the slot-winding and the end-winding—was found between the LPTN and the experimental data. Comparing the results from the LPTN and the FEA model, the maximum difference was 2% for the highest temperature in the slot-winding and end-winding. As for the LPTN sensitivity analysis, the thermal parameter with the highest sensitivity was found to be the liner-to-lamination contact resistance.

Background The availability of Mohs micrographic surgery (MMS) in Australia has increased dramatically since its inception in the 1980s. Objective This study aimed to describe the evolution of MMS practices at the Skin and Cancer Foundation Australia (SCFA) over the past 20 years (1997-2017). Methods Retrospective analysis of Mohs surgery cases at SCFA in 2017, 2007, and 1997, comparing data on sex, age, tumor type and site, initial tumor and final defect size, number of surgical stages and sections, and closure management. The present study is limited by being a retrospective analysis from a single institution. Results There was a 415% increase in the number of Mohs surgery cases from 1997 to 2017, and a significant increase in Mohs surgery-treated squamous cell carcinoma. The preoperative tumor and final defect size have decreased. More side-to-side closures and fewer grafts are being performed over time. Limitations Retrospective analysis from a single institution. Conclusion Over the last 20 years, MMS has remained appropriate in its application and is being increasingly used for treatment of squamous cell carcinoma suggesting improved access.

The future of electrification of vehicles and other systems will require the creation of high-power density power electronics with low junction-to-fluid thermal resistance cooling solutions. One way to create this solution is to move high-heat-flux liquid cooling (single- or two-phase) as close to the power electronics components as possible. One novel approach involves submersion in dielectric fluids as the cooling solution. We first provide the range of fluid properties and develop a figure of merit (FOM) to aid in dielectric fluid selection. Next, we perform computational fluid dynamics/heat transfer (CFD/HT) modeling using single-phase cooling (submerged jet impingement on an enhanced surface) to validate the dielectric fluid FOM. Results of the study show that the developed FOM is a good representation of the performance of the fluids when compared to the results of the CFD/HT analysis. Both FOM and the CFD/HT analysis show that based on pure thermohydraulic considerations, several commercially available fluids present higher performance, on the order of 5% of water. Finally, the FOM can be used to quickly assess the thermohydraulic performance of a dielectric fluid, as well as the secondary application-specific properties such as boiling point, saturation pressure, flash point, and global warming potential, thereby allowing for fluid candidates to be readily compared.

High-frequency ultrasonography is a bedside tool increasingly used for the assessment of skin lesions, but there have been few reports about its importance in children with skin signs of hematologic disease. We present three cases to highlight the usefulness of high-frequency ultrasonography in assisting with the diagnosis of these skin lesions.

Fundamental research and development of ultra-wide bandgap (UWBG) semiconductor devices are under way to realize next-generation power conversion and wireless communication systems. Devices based on aluminum gallium nitride (AlxGa1−xN, x is the Al composition), β-phase gallium oxide (β-Ga2O3), and diamond give promise to the development of power switching devices and radio frequency power amplifiers with higher performance and efficiency than commercial wide bandgap semiconductor devices based on gallium nitride (GaN) and silicon carbide (SiC). However, one of the most critical challenges for the successful deployment of UWBG device technologies is to overcome adverse thermal effects that impact the device performance and reliability. Overheating of UWBG devices originates from the projected high power density operation and poor intrinsic thermal properties of AlxGa1−xN and β-Ga2O3. This Perspective delineates the need and process for the “electro-thermal co-design” of laterally configured UWBG electronic devices and provides a comprehensive review of current state-of-the-art thermal characterization methods, device thermal modeling practices, and both device- and package-level thermal management solutions.

As energy systems move towards wide-spread electrification, penetration of power semiconductor devices and power electronics continue to grow at a rapid pace. This paper attempts at reviewing the state-of-the-art in power semiconductor modeling and the existing state of modeling in general on the design of devices and systems. The modeling needs for semiconductor devices vary depending on the end-goal, and the level of abstraction needed towards model formulation also changes with the size and complexity of the system to be designed. Finally, key aspects of thermal design and modeling for power electronics are also discussed.

Gallium oxide is an emerging wide band-gap material that has the potential to penetrate the power electronics market in the near future. In this paper, a finite-element gallium oxide semiconductor model is presented that can predict the electrical and thermal characteristics of the device. The finite element model of the two-dimensional device architecture is developed inside the Sentaurus environment. A vertical FinFET device architecture is employed to assess the device’s behavior and its static and dynamic characteristics. Enhancement-mode device operation is realized with this type of device architecture without the need for any selective area doping. The dynamic thermal behavior of the device is characterized through its short-circuit behavior. Based on the device static and dynamic behavior, it is envisioned that reliable vertical transistors can be fabricated for the power electronics applications.

High-frequency ultrasonography (HFUS) can help improve dermatofibrosarcoma protuberans (DFSP) recognition. We present three cases of DFSP in which a "jellyfish-like" sonographic pattern was a useful adjunct in formulating the diagnosis. In addition, we review all DFSP ultrasound images available in the literature.

Background Streptococcus pneumoniae causes about 826,000 deaths of children in the world each year and many health facility visits. To reduce the burden of pneumococcal disease, many nations have added pneumococcal conjugate vaccines to their national immunization schedules. Nicaragua was the first country eligible for GAVI Alliance funding to introduce the 13-valent pneumococcal conjugate vaccine (PCV13) in 2010, provided to infants at 2, 4, and 6 months of age. The goal of this study was to evaluate the population impact of the first five years of the program. Methods Numbers of visits for pneumonia, pneumonia-related deaths, and bacterial meningitis in both children and adults, and infant deaths between 2008 and 2015 were collected from all 107 public health facilities in Leon Department. Vital statistics data provided additional counts of pneumonia-related deaths that occurred outside health facilities. Adjusted incidence rates and incidence rate ratios (IRRa) in the vaccine (2011–2015) and pre-vaccine periods (2008–2010) were estimated retrospectively using official population estimates as exposure time. Results The IRRa for pneumonia hospitalizations was 0.70 (95% confidence interval [CI]: 0.66, 0.75) for infants, and 0.92 (95% CI: 0.85, 0.99) for one year-olds. The IRRa for post-neonatal infant mortality was 0.56 (95% CI: 0.41, 0.77). In the population as a whole, ambulatory visits and hospitalizations for pneumonia, as well as pneumonia-related mortality and rates of bacterial meningitis were lower in the vaccine period. Conclusions During the first five years of program implementation, reductions were observed in health facility visits for pneumonia in immunized age groups and infant mortality, which would be hard to achieve with any other single public health intervention. Future study is warranted to understand whether the lack of a booster dose (e.g., at 12 months) may be responsible for the small reductions in pneumonia hospitalizations observed in one year-olds as compared to infants.

A high-fidelity computational fluid dynamics (CFD)-based model for bubble nucleation of the refrigerant HFE7100 on micrometer-featured surfaces is presented in this work. The single-fluid, incompressible Navier-Stokes equations, along with energy transport and natural convection effects, are solved on a featured surface resolved grid. An a priori cavity detection method is employed to convert raw profilometer data of a surface into well-defined cavities. The cavity information and surface morphology are represented in the CFD model by geometric mesh deformations. Surface morphology is observed to initiate buoyancy-driven convection in the liquid phase, which in turn results in faster nucleation of cavities. Simulations pertaining to a generic rough surface show a trend where smaller size cavities nucleate with higher wall superheat. This local-scale model will serve as a self-consistent connection to larger device scale continuum models where local feature representation is not possible.

We report the first case series of allogeneic haematopoietic stem-cell transplant patients with graft versus host disease who developed cutaneous non-tuberculous mycobacteria infection. A multidisciplinary approach, reduction of immunosuppressive medications, combination of antibiotics, close skin surveillance and excision of suitable lesions are recommended in this specific subgroup.

Increasing the number of electric-drive vehicles (EDVs) on America?s roads has been identified by the U.S. Department of Energy (DOE), the federal cross-agency electric vehicle (EV)-Everywhere Challenge, and the automotive industry as a strategy with near-term potential for dramatically decreasing the nation?s dependence on oil. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on the optimization of thermal management.

Thermal management strategies for automotive power electronic systems have evolved over time to reduce system cost and to improve reliability and thermal performance. In this study, we characterized the power electronic thermal management systems of two electric-drive vehicles—the 2012 Nissan LEAF and 2014 Honda Accord Hybrid. Tests were conducted to measure the insulated-gate bipolar transistor-to-coolant thermal resistances for both steady-state and transient conditions at various coolant flow rates. Water-ethylene glycol at a temperature of 65°C was used as the coolant for these experiments. Computational fluid dynamics and finite element analysis models of the vehicle's power electronics thermal management system were then created and validated using experimentally obtained results. Results indicate that the Accord module provides lower steady-state thermal resistance as compared with the LEAF module. However, the LEAF design may provide improved performance in transient conditions and may have cost benefits.

Background Streptococcus pneumoniae causes an estimated 826,000 deaths of children in the world each year and many health facility visits. To reduce the burden of pneumococcal disease, many nations have added pneumococcal conjugate vaccines to their national immunization schedules. Nicaragua was the first country eligible for funding from the GAVI Alliance to introduce the 13-valent pneumococcal conjugate vaccine (PCV13), provided to infants at 2, 4, and 6 months of age. The goal of this study was to evaluate the population impact of the first five years of the program. Methods Numbers of visits for pneumonia, pneumonia-related deaths, bacterial meningitis, and infant deaths between 2008 and 2015 were collected from all 107 public health facilities in León Department. Vital statistics data provided additional counts of pneumonia-related deaths that occurred outside health facilities. Adjusted incidence rates and incidence rate ratios (IRRa) in the vaccine (2011–2015) and pre-vaccine periods (2008–2010) were estimated using official population estimates as exposure time. Results The IRRa for pneumonia hospitalizations was 0.70 (95% confidence interval [CI]: 0.66, 0.75) for infants, and 0.92 (95% CI: 0.85, 0.99) for one year olds. The IRRa for post-neonatal infant mortality was 0.56 (95% CI: 0.41, 0.77). In the population as a whole, ambulatory visits and hospitalizations for pneumonia, as well as pneumonia-related mortality and rates of bacterial meningitis were lower in the vaccine period. Conclusion Five years following program introduction, reductions were observed in health facility visits for pneumonia in immunized age groups and infant mortality, which would be hard to achieve with any other single public health intervention. Future study is warranted to understand whether the lack of a booster dose (e.g.,, at 12 months) may be responsible for the small reductions in pneumonia hospitalizations observed in one year-olds as compared with infants. Disclosures S. Becker-Dreps, Pfizer: Consultant and Grant Investigator, Consulting fee and Research grant; D. J. Weber, Pfizer: Consultant and Speaker’s Bureau, Consulting fee and Speaker honorarium

Background—While the pentavalent rotavirus vaccine was highly efficacious against rotavirus diarrhea in clinical trials, the vaccine’s effectiveness under field conditions in the developing world is unclear. In October, 2006, Nicaragua became the first developing nation to implement universal infant immunization with the pentavalent rotavirus vaccine. To assess the impact of the immunization program, we examined the incidence of diarrhea episodes between 2003 and 2009 among children in the state of Leon, Nicaragua. Methods—We extracted data on diarrhea episodes from health ministry records. We used scaled Poisson regression models to estimate diarrhea incidence rate ratios (IRR) for the period following the program’s implementation to the period before implementation. Results—Following implementation of the immunization program, diarrhea episodes among infants were reduced (IRR 0.85, 95% confidence interval [CI] 0.71–1.02) during the rotavirus season, but appear to have increased during other months. Conclusions—While the immunization program appears effective in reducing diarrhea episodes during the rotavirus season, a large burden of diarrhea persists during the remainder of the year.

Thermal management for electric machines (motors/generators) is important as the automotive industry continues to transition to more electrically dominant vehicle propulsion systems. Cooling of the electric machine(s) in some electric vehicle traction drive applications is accomplished by impinging automatic transmission fluid (ATF) jets onto the machine’s copper windings. In this study, we provide the results of experiments characterizing the thermal performance of ATF jets on surfaces representative of windings, using Ford’s Mercon LV ATF. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients. Fluid temperatures were varied from 50°C to 90°C to encompass potential operating temperatures within an automotive transaxle environment. The jet nozzle velocities were varied from 0.5 to 10 m/s. The experimental ATF heat transfer coefficient results provided in this report are a useful resource for understanding factors that influence the performance of ATF-based cooling systems for electric machines.Copyright © 2015 by ASME

Experiments were conducted to evaluate the use of a passive two-phase cooling strategy as a means of cooling automotive power electronics. The proposed cooling approach utilizes an indirect cooling configuration to alleviate some reliability concerns and to allow the use of conventional power modules. An inverter-scale proof-of-concept cooling system was fabricated and tested using the refrigerants hydrofluoroolefin HFO-1234yf and hydrofluorocarbon HFC-245 fa. Results demonstrated that the system can dissipate at least 3.5 kW of heat with 250 cm 3 of HFC-245fa. An advanced evaporator concept that incorporates features to improve performance and reduce its size was designed. Simulation results indicate the concept's thermal resistance can be 58% to 65% lower than automotive dual-side-cooled power modules. Tests were also conducted to measure the thermal performance of two air-cooled condensers-plain and rifled finned tube designs. The results combined with some analysis were then used to estimate the required condenser size per operating conditions and maximum allowable system (i.e., vapor and liquid) temperatures.

In 2010, Nicaragua became the first developing nation to add 13-valent pneumococcal conjugate vaccine (PCV-13) to its national immunization schedule, using a "3+0" dosing schedule. We assessed changes in incidence rates of health facility visits for childhood pneumonia and infant mortality after PCV-13 introduction in the Department of León, Nicaragua.We collected visit diagnoses from all 107 public health facilities in León between 2008 and 2012. We compared rates of pneumonia hospitalizations, ambulatory visits for pneumonia and infant mortality during the prevaccine (2008-2010) and vaccine (2011-2012) periods among different age groups of children using generalized estimating equations, accounting for clustering by municipality. Exposure time was estimated by official municipality population estimates.The adjusted incidence rate ratio for pneumonia hospitalization in the vaccine versus prevaccine period was 0.67 (0.59-0.75) among infants and 0.74 (0.67-0.81) among 1-year olds. The adjusted incidence rate ratio for ambulatory visits for pneumonia was 0.87 (0.75-1.01) among infants, and 0.84 (0.74, 0.95) among 1-year olds. The adjusted incidence rate ratio for infant mortality was 0.67 (0.57-0.80). We also observed lower rates of health facility visits for pneumonia among age groups (2- to 4-year old and 5- to 14-year old) not eligible to receive PCV-13.Within the first 2 years of a PCV-13 immunization program in Nicaragua, we observed lower rates of hospitalizations and ambulatory visits for pneumonia among children of all ages and a lower infant mortality rate. Lower rates of pneumonia among age groups not eligible to receive PCV-13 suggest an indirect effect of the vaccine.

A prospective study was conducted to assess general practitioners' diagnostic skills in a referral setting. The primary objective was to identify general practitioners' strengths and weaknesses in diagnosing a broad spectrum of skin conditions. The diagnoses of 315 skin conditions made by 165 general practitioners were compared with a reference standard. The reference standard was made up of 73 histopathological diagnoses, 119 dermatologists' clinical diagnoses and 123 dermatologists' diagnoses plus follow up. The diagnoses assigned by referring general practitioners were consistent with dermatologists' clinical diagnoses and histology (where available) in 57% of cases. General practitioners made the correct diagnosis in 44% of cases when compared with histopathology. General practitioners were generally good at diagnosing conditions such as acne, warts, rosacea, molluscum contagiosum, vitiligo and skin tags. The proportion of correct diagnoses for premalignant and malignant skin tumours was 47%, and that of skin rashes requiring a diagnosis was 44%. Further education of general practitioners would help to improve their diagnostic skills in certain skin conditions.

Multiple therapeutic options are available for treatment of Bowen's disease. The choice of therapy depends on clinical circumstance and medical practitioner experience. Newer therapies have more extensive support from the literature, but more established therapies may be preferred because of accessibility, cost and efficacy. An overview of the current therapeutic options for Bowen's disease is presented.

In this study experiments were performed to evaluate the spray cooling performance of three different spray nozzles using gassy-subcooled (∼Tsub = 31°C) FC-72 as the working fluid. The three different nozzles tested can be characterized as a single hollow cone spray nozzle (Nozzle A), 2×2 jet array spray nozzle (Nozzle B) and a 4×4 jet array spray nozzle (Nozzle C). For all tests, a 10×10 mm polished (600 grit) copper surface was utilized as the heater and tests were carried out at near atmospheric pressure conditions. All three nozzles were tested at various flow rates and nozzle-to-heater distances and the results were compared. Results show that changing the nozzle-to-heater distance affects heat transfer rates more than critical heat flux (CHF). The spray boiling curves for all three nozzles were similar with Nozzle C, for some cases, demonstrating the highest heat transfer rates. The disparity in CHF values between the various nozzles was more apparent. Compared at an equivalent flow rate, Nozzle C consistently produced CHF values which were higher than those of the other nozzles. Some common trends observed for all nozzles are, increasing flow rate increases heat transfer rates and critical heat flux (CHF) but decreases nozzle efficiency.Copyright © 2007 by ASME

Imiquimod is the first of a new class of drugs (immune response modifiers) to become commercially available. It is approved in many countries for the treatment of genital warts caused by the human papilloma virus infection. However, there are reports of its use in a variety of dermatological conditions, such as basal cell carcinomas, actinic keratoses, lentigo maligna, common warts and molluscum contagiosum. Its mechanism of action is through stimulation of the T helper cell Type 1 (Th1) immune response via activation of cell surface pathogen recognition receptors (mainly toll-like receptor 7). This activation stimulates the immune system's own defence mechanism against both virally infected and tumour cells. Imiquimod and other analogues show promise in the prophylactic treatment of skin tumours in some patients, especially those who are immunocompromised.