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Objectives With the advent of new optical technologies, early pharyngolaryngeal cancerous lesions can be better visualized. Although the conventional transnasal approach offers great views of the hypopharynx and larynx, the visualization of the oropharynx and palatine tonsils is limited. Through the transoral insertion of a flexible video-laryngoscope, direct views of the oropharynx and oral cavity can be obtained. Thus, transoral examination may contribute to primary detection of cancers of unknown primary (CUP). Methods Eighty-five CUP patients from Tokai University were included retrospectively in this study, from 2006 to 2017. Starting in 2010, we employed the transoral examination in addition to our conventional method. The primary detection rates were compared before and after 2010. Oropharyngeal primaries were further analyzed for tumor subsite and p16 status. Results The overall primary detection rate did not improve with the addition of transoral examination. However, greater numbers of oropharyngeal primaries were detected. The oropharyngeal lesions detected by transoral examination were mainly p16 positive, located on the palatine tonsil. Conclusion Transoral examination is a noninvasive, easy method to adopt in an outpatient setting, and a promising technique to improve tumor detection in this era of human papillomavirus-associated head and neck cancers. Level of evidence 3.

Interactive simulations allow preservice teachers to connect education theory and pedagogy in scaffolded environments. We created digital simulations with scenarios from in-person simulatio...

The properties of thermal networks are examined to understand the effective thermal conductivity of heterogeneous two-phase composite materials and systems. At conditions of high contrast in thermal conductivity of the individual phases (k1 and k2), where k1 &lt, &lt, k2 or k1 &gt, &gt, k2, the effective thermal conductivity of individual networks of the same composition was seen to be highly sensitive to the distribution of the phases and the presence of percolation paths across the network. However, when the contrast in thermal conductivities of the two phases was modest (k1/k2 ~ 10&minus, 2 to 102), the thermal networks were observed to exhibit an emergent response with a low variability in the effective thermal conductivity of mixtures of the same composition. A logarithmic mixing rule is presented to predict the network response in the low variability region. Excellent agreement between the model, mixing rule and experimental data is observed for a range two-phase porous and granular media. The modelling approach provides new insights into the design of multi-phase composites for thermal management applications and the interpretation or prediction of their heat transfer properties.

Between 2010 and 2011, an arterial road was constructed within provincially significant wetlands in the South March Highlands (SMH) located in Ottawa, Ontario, Canada. The wetlands and adjacent upland areas were determined to be sensitive habitat for Blanding’s Turtles (Emydoidea blandingii (Holbrook, 1838)) during the approval and permitting process, and a population study was required as part of the road construction project. The study consisted of a 4-year mark–recapture program and a movement study of radio-tagged adult turtles. General findings included the identification of 27 adult males and 55 females and a population estimate of 93 adults (95% Cl: 86–118). A 1:2.32 male to female sex bias was also found. Mean home-range size was 19.06 ha and tagged turtles moved, on average, more per observation in 2013 (191.40 m compared with 89.75 and 123.04 m in 2011 and 2012, respectively). Previously reported differences in movement patterns between males, females, and gravid females were not observed. The SMH Blanding’s Turtle population should be closely monitored because urban development continues in the area, which may further reduce the population size. Understanding the biology of imperiled populations across species’ ranges is necessary to promote conservation and adaptive wildlife management.

The purpose of this study was to investigate the effect of performance jewelry embedded with both a hologram and negative ions on maximal oxygen uptake (V[Combining Dot Above]O2max), V[Combining Dot Above]O2 at ventilatory threshold (V[Combining Dot Above]O2VT), or heart rate at ventilatory threshold (HRVT) measured through metabolic gas exchange. Eight males and 10 females (age = 26.5 ± 7.18 years) volunteered to participate in this study. Silicone bracelets with both hologram technology and negative ions were used as the “programmed” device. An identical silicone bracelet that did not contain the negative ion or hologram technology was used as the “nonprogrammed” device. A third condition in which the participants did not wear a band served as a control trial. The type of band worn during testing sessions was blinded from the participants and researchers. The order of testing was randomized. Subjects underwent 3 maximal graded exercise tests separated by 1 week. A repeated measure analysis of variance was used to test for mean differences across the 3 trials. The mean V[Combining Dot Above]O2max when wearing the programmed band (52.32 ± 4.79 ml·kg-1·min-1), when wearing the nonprogrammed band (51.47 ± 5.89), and without a band (53.32 ± 7.63 ml·kg-1·min-1) were found to be of no significant difference (p = 0.494). Assessment of the subjects HRVT under the 3 conditions (programmed, nonprogrammed, and no band) yielded no significant difference (p = 0.633). The HRVT of the above-mentioned 3 conditions were 136.06 ± 16.33, 135.00 ± 19.48, and 130.41 ± 24.39, respectively. The V[Combining Dot Above]O2VT for the programmed band (30.04 ± 6.91 ml·kg-1·min-1), nonprogrammed (30.77 ± 8.125 ml·kg-1·min-1), and no band (27.27 ± 8.66 ml·kg-1·min-1) were not significantly different (p = 0.221). The results of this study provide data that holographic and negative ion technology wristbands may have no effect on V[Combining Dot Above]O2max, V[Combining Dot Above]O2 at ventilatory threshold, or HRVT, and thus may have no positive effect on exercise endurance.

An experimental technique is demonstrated, in which the spatial variations of temperature inside a diesel oxidation catalyst (DOC) can be measured during an NEDC drive cycle. This leads to the development of a methodology which enables more scientific measurements to be performed on such a catalyst when it is connected to a live diesel engine. During hot and cold start NEDC drive cycles, measurements were performed on a Pt on alumina DOC connected to a Ford 2.0 litre diesel engine. Under these transient conditions, emission data was gathered (pre- and post-DOC), and this was also translated into cumulative emissions over the drive cycles. In addition, valuable data was gathered on the spatial temperature variations in the DOC during such a drive cycle and it is shown how, under certain conditions, the temperatures start to increase at the back-end of the catalyst and then move towards the front. This data, in combination with other measurements, helps to understand the performance of the DOC and can also be used to test the robustness of mathematical models of such systems.

A methodology was developed, which enables transient experiments to be performed on a DOC connected to a live diesel engine, while the temperature of the DOC substrate is monitored at various locations. This was demonstrated on a full-scale Pt/γ-alumina DOC (o.d. = 106 mm; length = 114 mm), connected to a Ford 2.0 L diesel engine. The engine was operated at a constant speed of 2000 rpm, and by varying the engine torque, experiments were performed at fixed gas inlet temperatures to the DOC, e.g. 150, 320 °C, and at each setting a constant background level of exhaust emissions was obtained. Then, a known quantity of pollutant (e.g. CO, propane) was injected into the exhaust, so as to create an approximated pulse input into the DOC (e.g. with peak CO concentration = 3000 ppm). The transient response of the system was monitored. So as to examine more closely local changes in response to a change in inlet conditions, experiments were also performed with a short 5 mm thin-slice of DOC (o.d. = 106 mm). These techniques enable better control to be achieved over such experiments, and provide valuable data to support mathematical modelling. It was interesting to note, that in the examples studied, there was no evidence of any significant competition between CO and THCs for the active sites. The DOC was also characterised, and it was shown that key properties can have different values depending on the location from which the sample was taken – and this would also have important implications on modelling work.

A methodology was developed, which helped to investigate the ‘light-off’ characteristics of a real diesel oxidation catalyst (DOC) while it was connected to a diesel engine. As a demonstration of the technique, trials were performed on a Ford 2.0 L engine, with a Pt on γ-alumina DOC (o.d. = 106 mm; length = 114 mm). By operating the engine at a constant speed (e.g. 2000 rpm), it was shown that when the engine torque was varied (e.g. from 5 to 47 N m), the gas inlet temperature to the DOC could also be varied (e.g. from 146 to 285 °C), while the gas composition and the mass flow of gas remained relatively constant—this enabled more scientific studies of catalyst ‘light-off’ to be performed on a real exhaust system. Experiments were also performed with higher background levels of a reactant (e.g. CO concentrations = 3000, 4000 and 5000 ppm), and hysteresis between ‘light-off’ and ‘light-down’ was observed. It was also shown how valuable additional information may be obtained from experiments using a thin-slice DOC (o.d. = 106 mm; length = 5 mm), and the CO inhibition effect was demonstrated on a real engine exhaust.

Existing methods for predicting heat fluxes and temperatures in internal combustion engines, which take the form of correlations to estimate the heat transfer coefficient on the gas-side of the combustion chamber, are based on methodology developed over the past 50 years, often updated in view of more recent experimental data. The application of these methods to modern diesels engines is questionable because key technologies found in current engines did not exist or were not widely used when those methods were developed. Examples of such technologies include: high-pressure common rail and variable fuel injection strategies including retarded injection for nitrogen oxides emission control; exhaust gas re-circulation; high levels of intake boost pressure provided by a single- or double-stage turbocharger and inter-cooling; multiple valves per cylinder and lower swirl; and advanced engine management systems. This suggests a need for improved predicting tools of thermal conditions, specifically temperature and heat flux profiles in the engine block and cylinder head. In this paper a modified correlation to predict the gas-side heat transfer coefficient in diesel engines is presented. The equation proposed is a simple relationship between Nu and Re calibrated to predict the instantaneous spatially averaged heat transfer coefficient at several operating conditions using air as gas in the model. It was derived from the analysis of experimental data obtained in a modern diesel engine and is supported by a research methodology comprising the application of thermodynamic principles and fundamental equations of heat transfer. The results showed that the new correlation adequately predicted the instantaneous coefficient throughout the operating cycle of a high-speed diesel engine. It also estimated the corresponding cycle-averaged heat transfer coefficient within 10 per cent of the experimental value for the operating conditions considered in the analysis.

Experimental data from internal combustion (IC) engines suggests that the use of proprietary computational fluid dynamics (CFD) codes for the prediction of coolant-side heat transfer within IC engine coolant jackets often results in underprediction of the convective heat transfer coefficient. An experimental and computational study, based on a coolant gallery simulator rig designed specifically to reproduce realistic IC engine operating conditions, has been conducted to explore this issue. It is shown that the standard ‘wall function’ approach normally used in CFD models to model near-wall conditions does not adequately represent some features of the flow that are relevant in convective heat transfer. Alternative modelling approaches are explored to account for these shortcomings and an empirical approach is shown to be successful; however, the methodology is not easily transferable to other situations.

Each year, over 173,000 children and adolescents visit emergency departments due to sports and recreation related concussions, an increase of 60% over the last decade due to the rise in the number of children participating in sport. While numerous authors have sought to address the epidemiology of concussions across multiple age groups who participate in contact sports, a recent review of literature did not reveal a substantial amount of published articles that addressed the issue of subconcussive contact. Multiple tools have been developed to assess acute episodes of concussion. Among the assessment protocols many include an assessment of balance, short and long term memory recall, and balance. The Child-SCAT3 was designed specifically to evaluate concussions in children 5-12 years of age.The purpose of this study was to determine the effect of a season of subconcussive contact on Child-SCAT3 scores in 8-12 year old males compared to their age matched peers who participated in non-contact sports. A secondary purpose was to evaluate how scores of the sub- components of the Child-SCAT3 compare between contact and non-contact athletes.A prospective cohort study was performed of 71 male athletes (58 football, 13 baseball) ages 8-12 (contact mean age 10.30 years, SD 1.20; non-contact mean age 10.03 years, SD 1.26) over the course of a season.Portions of The Child-SCAT3 were administered and scored in pre-adolescent athletes prior to and following a season of participation in football (contact sport group) and baseball (non-contact sport group). The outcome measures of interest included the portions related to Cognitive ability, Balance, and Coordination.No statistically significant differences were found in group, time or time and group interaction for any of the utilized portions of the Child-SCAT3. Statistically significant differences were found between groups for preseason cognitive orientation and postseason immediate memory. Cognitive orientation and coordination were also found to be statistically significantly improved across both groups over the course of the season.This study was potentially limited by the number of control subjects tested.A season of subconcussive contact in football was not detrimental to cognitive and balance scores on the Child-SCAT3.3.

Over the last 40 years, several empirical correlations have been developed to estimate heat fluxes from the combustion chambers of internal combustion engines. Some of these expressions are based on correlations to compute the Nusselt number for forced convection in turbulent flow inside circular tubes. The fundamental suitability of this kind of empirical model in representing the highly complex processes of in-cylinder heat transfer is questionable, but in practice the models have steadily improved owing to contributions from numerous investigators. Other correlations have a less theoretical basis than those of the Nusselt number form. Formulae of this type have been obtained from the application of simple statistical techniques to large datasets, taking into account several engine operational parameters and engine types. The resulting correlations provide reasonable estimates but perform poorly when extrapolated or applied to novel concepts. In this paper, the most important correlations are reviewed against the features of a modern diesel engine, and research requirements for future modelling developments are identified and discussed.

Frequently MRI data is characterised by a relatively low signal to noise ratio (SNR) or contrast to noise ratio (CNR). When developing automated Computer Assisted Diagnostic (CAD) techniques the errors introduced by the image noise are not acceptable. Thus, to limit these errors, a solution is to filter the data in order to increase the SNR. More importantly, the image filtering technique should be able to reduce the level of noise, but not at the expense of feature preservation. In this paper we detail the implementation of a number of 3D diffusion-based filtering techniques and we analyse their performance when they are applied to a large collection of MR datasets of varying type and quality.

The downhill filter is an elegant and efficient single pass reconstruction algorithm which demonstrates fast and consistent performance. It operates through a controlled process of region growing by ordered aggregation of surface pixels onto an expanding shell.

A detailed programme of work has been undertaken to quantify the suitability of predictive methods for accurate determination of the levels of boiling heat transfer within an internal combustion (IC) engine cooling gallery simulator. An extensive array of experimental data has been obtained as the basis for the predictive validation. Working on the principle of superposition, the convective component of heat transfer has been represented by the established Dittus-Boelter correlation which has been extensively modified to account for developing boundary layers, surface roughness and nearwall viscous effects. The boiling component has been represented by the Chen model, modified for binary fluids and subcooling. For the IC engine cooling application it is concluded that the application of the Chen approach must be complemented by a convective heat transfer model that accurately represents the complex thermo-fluid situation being experienced within a developing flow.

Simple heat transfer correlations are known to underpredict the single-phase convective heat transfer coefficient when applied to internal combustion (IC) engine cooling passages. The reasons for such underprediction were investigated using a specially designed test rig which was operated under a wide variety of test conditions relevant to IC engine operation. Data from this rig study identified that undeveloped flow (fluid dynamically and thermally), surface roughness and fluid viscosity variation with temperature were the physical reasons responsible for the mismatch. Simple empirical heat transfer models have subsequently been extended to take account of these factors and are shown to give much improved correlation with rig data, and data from an engine study. The implications of this work for predicting engine heat transfer in a three-dimensional computational fluid dynamics environment are discussed.

Previous research studies by Bolga, Ayotte, and Distefano have examined the level of muscle recruitment of the gluteal muscles for various clinical exercises; however, there has been no cross comparison among the top exercises from each study. The purpose of this study is to compare top exercises from these studies as well as several other commonly performed clinical exercises to determine which exercises recruit the gluteal muscles, specifically the gluteus medius and maximus, most effectively.Twenty-six healthy subjects participated in this study. Surface EMG electrodes were placed on gluteus medius and maximus to measure muscle activity during 18 exercises. Maximal voluntary muscle contraction (MVIC) was established for each muscle group in order to express each exercise as a percentage of MVIC and allow standardized comparison across subjects. EMG data were analyzed using a root-mean-square algorithm and smoothed with a 50 millisecond time reference. Rank ordering of the exercises was performed utilizing the average percent MVIC peak activity for each exercise.Twenty-four subjects satisfied all eligibility criteria and consented to participate in the research study. Five of the exercises produced greater than 70%MVIC of the gluteus medius muscle. In rank order from highest EMG value to lowest, these exercises were: side plank abduction with dominant leg on bottom (103%MVIC), side plank abduction with dominant leg on top (89%MVIC), single limb squat (82%MVIC), clamshell (hip clam) progression 4 (77%MVIC), and font plank with hip extension (75%MVIC). Five of the exercises recruited gluteus maximus with values greater than 70%MVIC. In rank order from highest EMG value to lowest, these exercises were: front plank with hip extension (106%MVIC), gluteal squeeze (81%MVIC), side plank abduction with dominant leg on top (73%MVIC), side plank abduction with dominant leg on bottom (71%MVIC), and single limb squat (71%MVIC). Four of the exercises produced greater than 70%MVIC for both gluteus maximus and medius muscles.Higher %MVIC values achieved during performance of exercises correlate to muscle hypertrophy.(20,22) By knowing the %MVIC of the gluteal musculature that occurs during various exercises, potential for strengthening of the gluteal muscles can be inferred. Additionally, exercises may be rank ordered to appropriately challenge the gluteal musculature during rehabilitation.

Statistical partitioning of images into meaningful areas is the goal of all region-based segmentation algorithms. The clustering or creation of these meaningful partitions can be achieved in number of ways but in most cases it is achieved through the minimization or maximization of some function of the image intensity properties. Commonly these optimization schemes are locally convergent, therefore initialization of the parameters of the function plays a very important role in the final solution. In this paper we perform an automatically initialized expectation-maximization algorithm to partition the data in medical MRI images. We present analysis and illustrate results against manual initialization and apply the algorithm to some common medical image processing tasks.

The successful realization of the goal of Model-Based Systems Engineering (MBSE) practice, to contain all project information in models, is predicated on the ability of the system model to represent the information needs of a broad range of stakeholders such as the owners, acquirers, suppliers, maintainers, and users. The paper opens by discussing the interface between the acquirer and supplier within the pre-contract competitive Australian defence context. From this and earlier work, the need for the model of the system of interest to be built upon a comprehensive knowledge representation that can support the creation and integration of multiple stakeholder specific models is derived. Elicitation of further requirements from both stakeholder workshops and from functional analysis follows. Refereed/Peer-reviewed