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As a curricular topic, the history of medicine can reinforce medical knowledge while integrating the benefits associated with humanities education. This study examined the degree to which medical history was present in the curricula of North American Medical Schools, how those sessions (if any) were delivered, and who delivered them. We hypothesized that medical history would be present but that very few American Medical schools would have mandatory sessions, that the presentation of this content would be very diverse, and that sessions would be presented by a variety of professionals. We compiled a contact list of deans and curricular administrators at each institution and recruited respondents from an online discussion board. Respondents completed a short survey regarding the curriculum at their home institution. We received responses from 96 of 209 institutions (46.0%). Of these, 29.2% of respondents indicated that their institution had mandatory sessions on medical history, 42.7% had non-mandatory curricular sessions, 49.0% had extracurricular sessions, and 21.4% had electives on the history of medicine. Lecture was the primary means of delivery in all modalities except for the electives, which primarily used small group discussion. Clinical faculty were the most common people overseeing these sessions, but a wide variety of others also contributed. While few North American medical schools had mandatory sessions on the history of medicine, the topic was present in very diverse ways. The lack of standardization in teaching the history of medicine may provide fertile ground for subsequent research in medical education.

In an effort to optimize the results during inguinal hernia repair, surgeons need to consider the role of different mesh fixation techniques. The use of tissue adhesives is proposed for mesh fixation, which demonstrate similar or improved outcomes in the realm of postoperative pain, hernia recurrence, cost, and formation of a hematoma or seroma. In this review, mesh fixation using fibrin glue and cyanoacrylate glue is compared to standard suture or tack techniques. The results of this investigation warrant consideration by surgeons seeking to improve patient outcomes.

Gross anatomy practical examinations have traditionally been composed of primarily free-response identification questions. Because student learning and study habits are influenced by testing, it is important that curricular design and objectives are reflected in all types of assessments, including those that take place in a laboratory setting. The use of higher-order and discipline-integrated questions on gross anatomy practical examinations reinforces the importance that anatomy knowledge has in clinical reasoning and assesses students’ ability to apply foundational information from an early point in their medical career. In this study, gross anatomy practical examinations were analyzed to assess the impact that higher-order and discipline-integrated testing modalities have on various measures of student performance. Two years of examinations (N = 338 questions) were reviewed and categorized by question type, Bloom’s taxonomy and discipline. Difficulty, discrimination index (DI) and point-biserial correlations were calculated for each question. These statistics were then compared between categories using Kruskal-Wallis tests with post-hoc pairwise comparisons (Dunn’s method). Results demonstrate that higher-order and discipline-integrated questions were significantly more difficult than traditional identification questions and tended to have higher mean DIs and point-biserials. Questions that targeted higher Bloom’s taxonomic levels were also found to be more difficult. This study demonstrates that integrated examinations can be incorporated into the gross anatomy laboratory, but suggests that this be done carefully as these changes can impact student performance.

The structures in the posterolateral corner of the knee, which stabilize the joint, are often involved in injuries to the posterior cruciate ligament. Familiar structures include the anterior cruciate ligament, posterior cruciate ligament, tibial collateral ligament, and menisci. Less familiar are the structures of the posterolateral corner, the most important of which are the fibular collateral ligament, popliteus tendon, and popliteofibular ligament, which resist varus angulation, external rotation, or posterior translation of the tibia. Injury to the posterolateral corner can be assessed with the posterolateral drawer, dial, reverse pivot shift, external rotation recurvatum, and varus stress tests. The purpose of this review is to highlight the posterolateral corner of the knee and injuries to its structures so that physicians can more accurately diagnose these injuries and provide appropriate treatment. Management focuses on restoring the fibular collateral ligament, popliteofibular ligament, and, in certain cases, the popliteus tendon.

Silicon carbide is a wide band gap semiconductor which presents excellent physical properties such as a high critical electric field strength which enables the realisation of efficient power devices [1]. The cubic silicon carbide (3C-SiC) polytype has been less investigated than the more popular hexagonal structure 4H-SiC. 3C-SiC has the advantage that it can be epitaxially grown on Si by chemical vapour deposition (CVD) [2] and presents properties suitable for achieving cost effective SiC power devices in the range 650V to 1200V. These 3C-SiC/Si substrates offer a promising alternative to the costly hexagonal SiC (4H-SiC) wafers and can also be used as template for the epitaxy of cubic GaN [3]. However, the presence of the Si substrate does limit the temperature available to anneal out the implantation damage generated by some device processing sequences. This work investigates the properties of metal silicides as a potential Schottky contacts for high blocking voltage 3C-SiC/Si Schottky barrier diodes (SBDs). For this study, Ti and Pt silicide contacts are formed on the (100)3C-SiC surface. The influence of the silicide formation temperature (500oC-650oC) on the contact electrical properties is investigated in detail. Current voltage (I-V) and capacitance voltage characteristics (C-V) are used to evaluate the reverse leakage current and extract the Schottky barrier height as well as the concentration of electrically active dopants in the N type 3C-SiC/Si. The Pt silicide Schottky contact is found to present higher energy barrier height than the Ti silicide Schottky contact and this trend was confirmed by the associated improved reverse current in the Pt Schottky. This is a promising result as it suggests that the reverse leakage is not dominated by the stacking faults inherent to this material. Temperature dependent I-V characteristics are measured and compared to theoretical I-V curves to explore the mechanisms responsible of the reverse leakage. The effort towards high blocking voltage final SBD device requires excellent PN junction edge termination. In this work, to avoid the damage caused by Al ion implantation, the electrical properties of 3C-SiC/Si PN junction diodes fabricated by epitaxy of P type 3C-SiC layers on N type 3C-SiC/Si substrates are also investigated. The reverse current mechanisms in the PN junction and the Schottky are compared and the suitability of the PN for device termination is discussed. [1] Kimoto, T., Cooper, J.A. Fundamentals of Silicon Carbide Technology: Growth, Characterization, Devices and Applications, Wiley, (2014) [2] A. Severino, C. Locke, R. Anzalone, et al., ECS Transactions, 35 (6), 99 (2011) [3] Okumura, H., Ohta, K., Feuillet, G., et al. Journal of Crystal Growth, 178 (1-2), 113, (1997)

The cubic polytype of SiC (3C-SiC) is the only one that can be grown on silicon substrate with the thickness required for targeted applications. Possibility to grow such layers has remained for a long period a real advantage in terms of scalability. Even the relatively narrow band-gap of 3C-SiC (2.3eV), which is often regarded as detrimental in comparison with other polytypes, can in fact be an advantage. However, the crystalline quality of 3C-SiC on silicon has to be improved in order to benefit from the intrinsic 3C-SiC properties. In this project new approaches for the reduction of defects will be used and new compliance substrates that can help to reduce the stress and the defect density at the same time will be explored. Numerical simulations will be applied to optimize growth conditions and reduce stress in the material. The structure of the final devices will be simulated using the appropriated numerical tools where new numerical model will be introduced to take into account the properties of the new material. Thanks to these simulations tools and the new material with low defect density, several devices that can work at high power and with low power consumption will be realized within the project.

Biomass allometry studies routinely assume that regression models can be applied across species and sites, and that goodness of fit of a regression model to its derivation dataset indicates both the relevance of the model to a new dataset and the likely error. Assuming that a model is relevant for a new sample, a prediction interval is a useful error measure for stand mass. Prediction coverage tests whether the model and hence the interval are appropriate in the new sample. Data for three similar shrubby species from four similar sites were combined in various ways to test the impact of varying levels of biodiverse heterogeneity on the performance of the four models most commonly used in published biomass studies. No one model performed consistently well predicting new data, and validation checks were not good indicators of prediction coverage. The highly variable results suggest that the common models might contain insufficient variables. Euclidean distance was used to quantify the relative similarity of samples as a possible means of estimating prediction coverage; it proved unsuccessful with these data.

The physical and electrical properties of 4-inch 3C-SiC epitaxial layers, deposited on Si (111) wafers, which were wafer bonded to polycrystalline silicon carbide carrier wafers, are presented. We show that this novel Si/SiC wafer bonding process leads to reduced wafer bow, confirmed by imaging, in the form of optical microscopy (×100 objective lens) together with a digital camera. All 3C-SiC layers grown above Si/SiC structures by conventional chemical vapor deposition techniques are shown to be single crystal in nature. 3C-SiC metal oxide semiconductor capacitors have been fabricated via thermal oxidation at 1100°C in pure oxygen for 90 minutes, with a density of interface states measured at ∼2 × 1011 cm−2 eV−1 at 0.2 eV beneath the conduction band edge. These structures have the potential to realize thick, bow-free 3C-SiC layers suitable for power device fabrication.

A connective tissue link between the spinal dura mater and the rectus capitis posterior minor muscle was first described in 1995 and has since been readily demonstrated via dissection, magnetic resonance imaging, and plastinated cross-sections of the upper cervical region (Hack et al. [1995] Spine 20:2484-2486). This structure, the so-called "myodural bridge," has yet to be included in any of the American anatomy textbooks or dissection guides commonly used in medical education. This direct anatomic link between the musculoskeletal system and the dura mater has important ramifications for the treatment of chronic cervicogenic headache. This article summarizes the anatomic and clinical research literature related to this structure and provides a simple approach to dissect the myodural bridge and its attachment to the posterior atlanto-occipital membrane/spinal dura mater complex and summarizes the case for its possible inclusion in medical anatomy curricula.

Three approaches to study have been described in phenomenographic educational research: deep, strategic, and surface. Deep approaches to learning have been correlated with meaningful learning and academic success, whereas surface approaches produce an externalization of learning and poor outcomes. Students adopting a strategic approach adopt either a deep or surface approach in response to perceived examination demands. Despite being well known in Europe and Australia, this research paradigm has been applied sporadically in the United States. In this study, the approaches to study of a group of first year American medical students were collected using the Approaches and Study Skills Inventory for Students instrument at the beginning and end of their first year to find how consistent these approaches remained over time. At both times, the majority of participants adopted deep approaches, followed by strategic and then surface approaches. The percentage of participants using a surface approach grew during the first year but never exceeded 10%. The mean anatomy grades of students adopting each approach were then compared to find how each approach correlated with success in the course. Mean grades of students using a strategic approach were significantly higher than average at both times. Students who maintained a strategic approach throughout the first year had significantly higher mean grades than average while students who changed to a surface approach had significantly worse mean anatomy grades. Problem-based students had significantly higher scores on several deep submeasures than lecture-based peers and female students demonstrated greater fear of failure than male peers at both times.

This paper investigates the origin of the fixed positive oxide charge often experimentally observed in Metal Oxide Semiconductor (MOS) structures of SiO2 formed on cubic silicon carbide (3C-SiC). The electrical properties of MOS structures including either thermally grown SiO2 or deposited SiO2 by Plasma Enhanced Chemical Vapour Deposition (PECVD) on epitaxial 3C-SiC layers grown directly on Si are investigated. MOS structures with a range of oxide thickness values subjected to different thermal treatments were studied. It was found that both thermally grown and deposited SiO2 on 3C-SiC exhibit similar positive charge levels indicating that the charge originates from interface states at the 3C-SiC surface and not from the oxide. The nature of this surface charge in the SiO2/3C-SiC system is also discussed based on the current data and previously published results.

The purpose of this investigation was to quantitatively and qualitatively identify the study methods and learning strategies that veterinary students used to study anatomy during their first year of professional school and to correlate these with their academic achievement and long-term recall of information. It was surmised that active study methods would be more beneficial than passive method, but this hypothesis was not supported. The activity or passivity of each study method was secondary to the way in which the students processed the learning. No single study method was associated with academic success or long-term recall; instead, successful students used a multitude of study methods while the struggling students relied on a single method alone, although these methods varied from student to student. Students and their study methods were profiled using the qualitative technique known as phenomenographic analysis to find those who studied in a deep or surface way. The deep-processing students, who commonly used multiple study methods, not only succeeded in the class but also had better recall. Students who relied on a memorization-heavy surface approach to learning had limited recall and tended to perform poorly in the class. These results strongly suggest that by encouraging students to integrate their studying by using multiple methods educators can improve both student grades and recall of complex topics. Anat Sci Ed 1:68–74, 2008. © 2008 American Association of Anatomists.

The infraspinatus fascia is a tough sheet of connective tissue that covers the infraspinatus fossa of the scapula and the muscle within. Muscle fibers originate from the fossa and fascia and then travel laterally to insert on the greater tubercle of the humerus. Frequently the infraspinatus fascia is quickly removed to appreciate the underlying muscle, but the fascia is an interesting and complex structure in its own right. Despite having a characteristic set of fascial bundles, no contemporary anatomy texts or atlases describe the fascia in detail. The infraspinatus fascia was dissected in detail in 11 shoulders, to characterize the fascial bundles and connections that contribute to it. Thereafter, 70 shoulders were dissected to tabulate the variability of the fascial bundles and connections. Six characteristic features of the infraspinatus fascia were noted: a medial band, an inferior-lateral band, and superior-lateral band of fascia, insertion of the posterior deltoid into the infraspinatus fascia, a transverse connection from the posterior deltoid muscle to the infraspinatus fascia, and a retinacular sheet deep to the deltoid and superficial to the infraspinatus and teres minor muscles. Although other structures of the shoulder are more frequently injured, the infraspinatus fascia is involved in compartment syndromes and the fascial bundles of this structure are certain to impact the biomechanical function of the muscles of the posterior shoulder.

Biomass allometry studies routinely assume that regression models can be applied across species and sites, and that goodness of fit of a regression model to its derivation dataset indicates both the relevance of the model to a new dataset and the likely error. Assuming that a model is relevant for a new sample, a prediction interval is a useful error measure for stand mass. Prediction coverage tests whether the model and hence the interval are appropriate in the new sample. Data for three similar shrubby species from four similar sites were combined in various ways to test the impact of varying levels of biodiverse heterogeneity on the performance of the four models most commonly used in published biomass studies. No one model performed consistently well predicting new data, and validation checks were not good indicators of prediction coverage. The highly variable results suggest that the common models might contain insufficient variables. Euclidean distance was used to quantify the relative similarity of samples as a possible means of estimating prediction coverage; it proved unsuccessful with these data.

Amidst continual global population growth, land degradation and climate change, consumers are becoming more aware of the environmental impact of their diet. People in cities are also looking to mitigate the risk of disruption to their food supply through adoption of urban agriculture (UA). It is not at all clear, however, what impact UAwill ultimately have on urban food security. The informal nature of many UA enterprises makes quantification difficult, and some projections of cities “feeding themselves” appear to simply reflect untested optimism. This paper demonstrates the novel use of Linear Programming (LP) to explore different dietary preferences (high meat intake versus vegetarian), and to determine the feasibility of urban agriculture (UA) making a substantial contribution to food security. The model quantifies the maximum potential impact of locally-grown produce in terms of either reducing cost or maximising the dietary contribution. Results show that LP can be used effectively to explore optimal cropping on urban land, based on the amount of available land per capita. A key finding of this feasibility study is that the contribution of UA to realistic diets—while limited—need not be trivial. In our case study of Northern Adelaide, Australia, it appears that 10–15% of dietary protein could be produced in a typical suburban backyard, with or without chicken meat, along with savings of around AU$1 per person per day. Both the nature of the optimal UA crop regime and its impact are shown to depend on the dietary context, especially the level of meat consumption. Refereed/Peer-reviewed

FGF5 is expressed in the mesenchyme and skeletal muscle of developing and adult mouse limbs. However, the function of FGF5 during development of the limb and limb musculature is unknown. To elucidate the inherent participation of FGF5 during limb organogenesis, a retroviral delivery system (RCAS) was used to overexpress human FGF5 throughout developing hind limb of chicken embryos. Misexpression of the soluble growth factor severely inhibited the formation of mature myocytes. Limbs infected with RCAS-FGF5 contained smaller presumptive muscle masses as evidenced by a decrease in MyoD and myosin heavy chain expressing cells. In contrast, ectopic expression of FGF5 significantly stimulated proliferation and expansion of the tenascin-expressing, connective-tissue fibroblast lineage throughout the developing limb. Histological analysis demonstrated that the increase in tenascin immunostaining surrounding the femur, ileum, and pubis in the FGF5 infected limbs corresponded to the fibroblasts forming the stacked-cell perichondrium. Furthermore, pulse labeling experiments with the thymidine analog, BrdU, revealed that the increased size of the perichondrium was attributable to enhanced cell proliferation. These results support a model whereby FGF5 acts as a mitogen to stimulate the proliferation of mesenchymal fibroblasts that contribute to the formation of connective tissues such as the perichondrium, and inhibits the development of differentiated skeletal muscle. These results also contend that FGF5 is a candidate mediator of the exclusive spatial patterning of the hind limb connective tissue and skeletal muscle. © 2000 Wiley-Liss, Inc.

Different approaches to study lead to differing academic outcomes. Deep and strategic approaches have been linked to academic success while surface approaches lead to poorer understandings.This study sought to characterize how the approaches to study used by medical students impacted their academic success as measured by three outcomes: cumulative grades at the end of the first year, cumulative grades at the end of the second year, and performance on a medical licensing examination.The approaches and study skills inventory for students was administered to medical students to determine their predominant study approach (deep, strategic, superficial) at the beginning of their first year, end of first year, and end of second year. Each group's mean performance on each outcome measure was compared by ANOVA to find significant differences.For all three outcome measures, strategic approaches to study were associated with high performance while surface approaches with a poor one. Deep approaches were most popular at all times and were largely associated with adequate performance.Deep approaches to study are sufficient for success in the current paradigm of medical education but strategic ones may offer a selective advantage to those who use them. Surface approaches to study must be discouraged by instructors through deliberate course design.

OBJECTIVE AND IMPORTANCE: Infundibula (IFs) are funnel-shaped symmetrical enlargements that occur at the origins of cerebral arteries and are apparent on 7 to 25% of otherwise normal angiograms. They are frequently considered as normal anatomic variants of no pathogenic significance. CLINICAL PRESENTATION: We report the case of a ruptured posterior communicating artery aneurysm that had developed at the site of a previously known IF in a 49-year-old hypertensive woman. She had a poor conscious level at admission, with widespread subarachnoid hemorrhage and obstructive hydrocephalus. INTERVENTION: The patient was immediately ventilated, and an external ventricular drain was inserted. The aneurysm was successfully clipped; however, secondary hemorrhage occurred both before and during craniotomy. She developed marked hypernatremia and subsequently died. CONCLUSION: This is the 11th case of IF-to-aneurysm progression reported. It suggests that in certain cases, serial investigations may be indicated with IFs to detect aneurysm formation and preempt rupture.

Twenty-five human placentas were studied for suitability in a microvascular exercise. The size and useful length of vessels were measured, and different microvascular anastomoses were performed. The size of the placenta vessels compared well with reported sizes of intracranial arteries. We suggest the use of placenta by neurosurgeons as complementary to experimental animals in microvascular training.

The determination of microwave transistor s parameters over a frequency band up to 10 GHz by means of timedomain techniques, involving Fourier analysis and deconvolution of transient response data, is described. Details of the measurement system are presented and advantages of such techniques over conventional network analyzer techniques are discussed. Results obtained for developmental ion-implanted/diffused-silicon bipolar transistors with ft values above 5 GHz are presented.

The results of treating acute or chronic pain with Distalgesic were compared in a double-blind fashion with the new partial antagonist analgesic meptazinol. Both drugs had similar analgesic time effect profiles and both were acceptable to doctor and patients. However the side-effect profile was better for meptazinol than Distalgesic and so meptazinol may be a useful alternative to Distalgesic in the treatment of everyday pain states.

A proposal to increase the existing residential LV grid voltage from 230 V has been made in order to increase existing network capacity. A power-electronic AC-AC converter is then used to provide 230 V at each property. Several constraints such as temperature rise at the converter location lead to a converter design requiring very high efficiency. In this paper results from a recent feasibility study in terms of LV network capacity increase are presented along with the design and testing of a SiC based 1 kW, AC/AC prototype module, which forms the basis of a much larger 15 kW multi-module converter.