Search

Fluid flow through porous material is relevant in different fields of engineering, such as in engine and vehicle development, and can be supported through CFD simulation. Numerical simulations at the pore-scale can be used to replace or reduce expensive laboratory measurements. These methods offer a valuable opportunity to connect the pore-scale properties of the porous material with displacement processes on the continuum-scale. Furthermore, they allow researchers to specify crucial flow properties, e.g., capillary pressure, which are crucial for REV-scale research. Three main methods, direct numerical, pore network modeling, and hybrid approaches, are widely used in order to analyze the pore-scale mechanics of fluid flow behavior through porous materials with CFD simulations. The present comprehensive review demonstrates and highlights the significant advantages, disadvantages, and critical challenges in the pore-scale fluid flow simulations. The main challenges include the characterization of material properties, and up-scaling process from pore to continuum or field-scale.

To date, huge amounts of money have been invested in the development of internal combustion engines to reach the current level of technology. High specific power and good thermal efficiency have been achieved, thanks to which, internal combustion engines are now widely used. However, the driving force behind the developments is no longer the high performance, but the compliance with strict emission standards. Future emissions regulation, namely Euro 7, will be challenging for engine and vehicle manufacturers. One possible technical solution may be to use a stoichiometric air-fuel mixture on the entire engine map to meet the requirements of the Euro 7 emission standard. This article analyzes the change in Euro regulations in the light of Euro 7, as well as the theoretical background of the λ = 1 operation. Several technical possibilities to achieve the stoichiometric ratio, such as e.g. water injection or variable compression ratio are presented.

This is a revision of the previous joint Policy Statement titled “Guidelines for Care of Children in the Emergency Department.” Children have unique physical and psychosocial needs that are heightened in the setting of serious or life-threatening emergencies. The majority of children who are ill and injured are brought to community hospital emergency departments (EDs) by virtue of proximity. It is therefore imperative that all EDs have the appropriate resources (medications, equipment, policies, and education) and capable staff to provide effective emergency care for children. In this Policy Statement, we outline the resources necessary for EDs to stand ready to care for children of all ages. These recommendations are consistent with the recommendations of the Institute of Medicine (now called the National Academy of Medicine) in its report “The Future of Emergency Care in the US Health System.” Although resources within emergency and trauma care systems vary locally, regionally, and nationally, it is essential that ED staff, administrators, and medical directors seek to meet or exceed these recommendations to ensure that high-quality emergency care is available for all children. These updated recommendations are intended to serve as a resource for clinical and administrative leadership in EDs as they strive to improve their readiness for children of all ages.

The recent successful launch of the Orbital Micro Systems GEMS-1 IOD (Global Environmental Monitoring System In-orbit Demonstrator) satellite carrying the University of Colorado’s MiniRad 118-GHz imager/sounder instrument provides the basis for a new means of observing atmospheric precipitation, temperature, and related state variables. GEMS-1 supports an 8-channel passive microwave radiometer operating at the 118.7503 GHz oxygen resonance with cross-track scanning imaging system providing cross- and along track Nyquist sampling at 17 km 3dB spatial resolution. It is precisely calibrated using cold space views along with and an on board reference, yielding the first low-cost commercial weather satellite imagery. GEMS is the first of a constellation of approximately 50 such satellites of progressively improving resolution and spectral coverage that will collectively provide Nyquist time-sampling of precipitation and related weather variables on a global basis, and using microwave frequencies will provide such information probing through most cloud cover. Presented will be first light imagery and on-orbit performance data from the GEMS-1 mission, including validation data on the satellite brightness temperatures. Products will include calibrated multispectral imagery, temperature profiles, retrieved rain rate, and precipitation cell top altitude. The expansion of the GEMS-1 mission to the full GEMS constellation will be outlined.

The objective of this investigation is to explore the use of hand gestures to control semi-autonomous vehicles. This was achieved through the use of simulations built in Unity and real-life demonstrations. Screen-spaced simulations modeled the control of a recreational quadcopter while Virtual Reality simulations followed by actual demonstrations used a small ground vehicle. The purpose of the actual demonstrations was to validate observations and lessons learned about vehicle control and human performance from the simulations. The investigative process involved identifying natural gestures to control basic functions of a vehicle, matching them to the selected gesture capture technology, developing algorithms to interpret those gestures for vehicle control, and arranging the appropriate visual environment using the Unity game engine to investigate preferred use of those gestures. Observations and participant feedback aided in refining the gesture algorithms for vehicle control and visual information, indicated the simulations provided suitable learning experiences and environments from which to assess human performance. Results indicate that the gesture-based approach holds promise given the availability of new technology.

In this investigation we seek to understand user technology interface preferences and simulation features for exploring physics-based concepts found in engineering educational programs. A 3D magnetic field emanating from a bar magnet was used as the representative physics concept. The investigation developed three different virtual environments using three different technologies and exploiting the capabilities available through the use of those technologies. This provides a suite of platforms to compare and identify the types of interactions and control capabilities a user prefers when exploring this type of phenomena. These environments will now enable the behaviors and preferences to be identified through observation of the user as they navigate the event and manipulate various options available to them depending upon the technology used.

Background: Anthraquinones are a possible treatment option for oncological patients due to their anti-cancer properties. Cancer patients often exhaust a plethora of resources that ultimately fail to provide fully curative measures. Alternative treatments are subsequently sought in the hope of finding a therapeutic remedy. Po¬tential regimens include aloe-emodin and its related derivatives. This review therefore summarizes the effects of aloe-emodin and other aloe components in light of their anti-proliferative and anti-carcinogenic properties. Methods: A systematic search was performed in PubMed for aloe-emodin and cancer in humans. Sixty abstracts of in vitrostudies were selected and reviewed with subsequent screening of the full text. Thirty-eight articles were summarized. Results: Aloe-emodin possesses multiple anti-proliferative and anti-carcinogenic properties in a host of human cancer cell lines, with often multiple vital pathways affected by the same molecule. The most notable effects include inhibition of cell proliferation, migration, and invasion; cycle arrest; induction of cell death; mitochondrial membrane and redox perturbations; and modulation of immune signaling. The effects of aloe-emodin are not ubiquitous across all cell lines but depend on cell type. Conclusions: On the basis of this systematic review, the multiple consistent effects of aloe-emodin in hu¬man-derived cancer cell lines suggest that aloe-emodin is a potential anti-cancer agent that acts on cancer cells in a pleiotropic manner. Relevance for patients: Cancer patients often utilize alternative therapies as a result of suboptimal efficacy of conventional treatments. Aloe-emodin might become a therapeutic option for cancer patients if the basic research is confirmed in clinical trials.

The accuracy of atmospheric density measurements inferred from satellite drag is limited by errors in drag coefficient estimates. In this work, we use a unique opportunity in which the Drag and Atmospheric Neutral Density Explorer satellite and three Polar Orbiting Passive Atmospheric Calibration Spheres are deployed from a common launch vehicle. Each object flies through similar atmospheric conditions but has a different area-to-mass ratio. This allows aerodynamic analysis that is independent of atmospheric density via comparisons of measured and modeled ballistic coefficient ratios. A test particle method combined with a satellite energy accommodation model is used to model the aerodynamics of these objects. Fitted ballistic coefficients computed as a result of special-perturbations orbit analysis are then compared to the model results. The drag coefficient model and observations agree at the 1–2% level when coefficient ratios are compared. Comparisons of an additional shape with model predictions are m...

The purpose of this investigation was to assess user preferences for controlling an autonomous system. A comparison using a virtual environment (VE) was made between a joystick based, game controller and a gesture-based system using the leap motion controller. Command functions included basic flight maneuvers and switching between the operator and drone view. Comparisons were made between the control approaches using a representative quadcopter drone. The VE was designed to minimize the cognitive loading and focus on the flight control. It is a physics-based flight simulator built in Unity3D. Participants first spend time familiarizing themselves with the basic controls and vehicle response to command inputs. They then engaged in search missions. Data was gathered on time spent performing tasks, and post test interviews were conducted to uncover user preferences. Results indicate that while the gesture-based system has some benefits the joystick control is still preferred.

The purpose of this study is to investigate the functionality and effectiveness of hand gestures to control flight operations and onboard equipment of unmanned aerial vehicles (UAVs). This study utilizes the Leap Motion Controller (LMC) to sense hand motions. The LMC is a gesture based, human-computer interface (HCI) device. For this application, a primitive gesture library was developed by considering fundamental UAV operations. The LMC application programming interface was then used to implement an interpreter to identify the motions and translate them into UAV performance and control commands. Careful attention was paid to identifying and developing natural, intuitive, and common hand gestures that can be sensed in the LMC field of view. It is anticipated that this work will provide the framework from which to develop a gesture based library for actual UAV control and other LMC applications.

Objective:Morbidity associated with suspension laryngoscopy has been well documented. However, standard of care with regard to postoperative analgesia has not been described, and anecdotal evidence suggests wide variability with regard to postoperative narcotic and non-narcotic recommendations. We sought to quantify the postoperative course following suspension microlaryngoscopy by relating patient-based and intraoperative measures with analgesic use.Methods:Body mass index (BMI), Friedman tongue position (FTP), and Mallampati scores as well as laryngoscope type, number of attempts required for optimal visualization, and suspension time were documented in 50 consecutive patients undergoing routine suspension microlaryngoscopy. Postoperative symptoms and analgesic use was queried on postoperative days 1, 3, and 10.Results:In this cohort, 62.5% employed postoperative analgesia. However, only 20% required narcotics. No difference in suspension time was identified in those taking analgesics (33.0 vs 37.3 minutes, P = .44). In addition, no relationship between procedure type and the need for analgesia was noted. The majority of patients (76%) described sore throat persisting for 3 postoperative days; 36% reported sore throat persisting beyond postoperative day 3.Conclusions:The majority of patients undergoing microlaryngoscopy reported discomfort, but symptoms were largely ameliorated with over-the-counter analgesics. Routine prescription of narcotics following routine suspension laryngoscopy may be unnecessary.

In this paper, the Real World Design Challenge (RWDC) competition is discussed in detail. This paper highlights the need, history, and approach taken for the design of the challenge. The authors discuss how this challenge promotes Science, Technology, Engineering and Mathematics (STEM) education and provides opportunities for high school students to acquire knowledge and experience beyond their traditional curriculum. The challenge is based around a real world problem. Students are asked to work in teams to find feasible solutions for the identified problem. The process for developing the challenge, student engagement, learning opportunities, student evaluations, publicity and recruitment efforts, design objective and timeline, and assessment metrics are some of the topics discussed. In this paper, the lessons learned from developing and running the challenge are also addressed.

Haemophilus influenzae is serologically classified into two main categories based on the presence or absence of the polysaccharide capsule. Strains that possess polysaccharide capsules are identified as typeable Haemophilus influenzae, whereas strains that do not have capsules are identified as non-typeable Haemophilus influenza. Only on very rare occasions, Haemophilus influenzae affects adult joints, and almost 95% of cases have been identified as type b serotypes. Coexistence of gouty and septic arthritis is rare but has been reported. We herein report a case of polyarticular septic arthritis caused by non-typeable Haemophilus influenzae in an adult with concomitant new-onset gouty arthritis. The case was successfully treated with surgical debridement and a 4-week course of ceftriaxone.

In this paper we report on a pilot study conducted to identify tasks and understand scale and spatial resolution limits for the design of virtual engineering laboratories. The virtual environment is based on using the Oculus Rift SDK2 headset combined with the Leap Motion Controller (LMC) mounted on the headset. We first discuss a functional break-down structure to identify typical tasks conducted in a laboratory. From this functional breakdown basic gestures are identified to assist in virtual laboratory operations. Using this breakdown as a guide we developed two virtual environments. The first familiarizes the user with basic capabilities of the Rift and LMC. While the second environment was developed to measure scale and spatial effects of interfaces. This data will be used to guide the development of virtual laboratories environments for use in engineering degree programs and improve testing of these and other interfaces.

The present review aims to illustrate the strategies that are being implemented in regenerative medicine to treat diseases that affect the digestive tract. Possible avenues are twofold: organ bioengineering, where cells are seeded on biological or synthetic scaffolding materials ex vivo and allowed to either mature in bioreactors or be implanted without undergoing any maturation; and regeneration per se, where the diseased tissue or organ is regenerated by recapitulation of its multi-step ontogenesis. This latter avenue may be induced either in vivo or ex vivo. While bioengineering technology has already manufactured segments of the digestive tract and sphincters, pure regeneration of any segment of the digestive tract has not yet been described. However, models of regeneration extrapolated from simple organisms are elucidating the complex yet fascinating mechanisms that regulate the ontogenesis of the digestive tract and are paving the way for the development of new regenerative technologies and methods.

This article introduces the design process of a multi-functional skin structure for thermal energy transport and load bearing by using topology optimization. A single cell with periodic boundary conditions in the in-plane direction is used as a design space so that the final single-cell design can be repeated to construct a continuous sheet of material. The newly engineered skin is developed using two materials to meet two required functionalities of a Sensorcraft wing skin; one is to maximize the conductivity of the skin in thickness direction in order to dissipate internal heat into the air, sink, and minimize the inside skin surface temperature passively, thereby, allowing the thermoelectric device to operate at an optimum condition. The other is to maximize the in-plane stiffness to provide the load-bearing capability of the skin to an external load such as torsion. A multi-functional optimization scheme using a linear combination of two objective functions with weights is used to find the optimal layout of the two materials. A specimen was manufactured and multiple-cell analysis of aluminum block, plug configuration, and optimal configuration was conducted to compare the temperature-convergence history according to the number of cells.

Studies are presented that characterize the dynamic aeroelastic aspects of a morphing aircraft design concept. The notion of interest is a folding wing design resulting in large-scale wing area changes. A finite element approach is used to investigate the sensitivity of natural frequencies and flutter instabilities to the wing position (e.g., fold angle), actuator stiffness, and vehicle weight. Sensitivities in these areas drive design requirements and raise flight envelope awareness issues. The study is presented in two parts as a comparison between two models of varying complexity. A simple folding wing model, based on the Goland wing, is analyzed and results are compared with a built-up structural model of the proposed full scale morphing vehicle.

The paper introduces an innovative topology optimization approach for determining the distribution of structural properties and actuators to design amorphing wing that is capable of achievingmultiple target shapes. The previous investigation by the authors demonstrated, using various problem formulations and a novel modeling concept, the fundamental topology synthesis of a simple two-configurationmorphingwing structure.Theprimary objective of the present investigation is therefore to introduce improvements and extensions to the previous concepts and problem formulations to those capable of accommodating the multiple-configuration definitions. The investigation includes the formulation of appropriate topology optimization problems and the development of effective modeling concepts. In addition, principal issues on the external load dependency and the reversibility of a design, as well as the appropriate selection of a reference configuration, are addressed in the investigation. The methodology to control actuator distributions and concentrations is also discussed. Finally, an examplemultiple-configuration problem that portrays the generic surveillance mission is solved to demonstrate the potential capabilities of the approach.

In this study, the optimal location of a distributed network of actuators within a morphing wing scissor mechanism is investigated. The analysis begins by developing a mechanical understanding of a single cell representation of the mechanism. This cell contains four linkages connected by pin joints, a single actuator, two springs to represent the bi-directional behavior of a flexible skin, and an external load. Equilibrium equations are developed using static analysis and the principle of virtual work equations. An objective function is developed to maximize the efficiency of the unit/multiple cell model. It is defined as useful work over input work. There are two constraints imposed on this problem. The first is placed on force transferred from the external source to the actuator. It should be less than the blocked actuator force to ensure the mechanism moves in the desired direction. The other is the requirement that the ratio of output displacement over input displacement, i.e., geometrical advantage (GA), of the cell is larger than a prescribed value. Sequential quadratic programming is used to solve the optimization problem. This process suggests a systematic approach to identify an optimum location of an actuator and to avoid the selection of location by trial and error. Preliminary results show that optimum locations of an actuator can be selected out of feasible regions according to the requirements of the problem, such as a higher GA, a higher efficiency, or a smaller transferred force from external force. Results include analysis of single and multiple cell wing structures and some experimental comparisons.

This paper presents a novel topology optimization methodology for a synthesis of distributed actuation systems with specific applications to morphing air vehicle structures. The main emphasis is placed on the topology optimization problem formulation and the development of computational modeling concepts. The analysis model is developed to meet several important criteria: It must allow a large rigid-body displacement, as well as a variation in planform area, with minimum strain on structural members while retaining acceptable numerical stability for finite element analysis. For demonstration purposes, the in-plane morphing wing model is presented. Topology optimization is performed on a semiground structure with design variables that control the system configuration. In other words, the state of each element in the model is controlled by a corresponding design variable that, in turn, is determined through the optimization process. In effect, the optimization process assigns morphing members as soft elements, nonmorphing load-bearing members as stiff elements, and nonexistent members as "voids." The optimization process also determines the optimum actuator placement, where each actuator is represented computationally by equal and opposite nodal forces with soft axial stiffness. In addition, the configuration of attachments that connect the morphing structure (i.e., morphing wing) to a nonmorphing structure (i.e., fuselage) is determined simultaneously in the same process. Several different optimization problem formulations are investigated to understand their potential benefits in solution quality, as well as meaningfulness of the formulations. Sample in-plane morphing problems are solved to demonstrate the potential capability of the methodology introduced in this paper.

This paper presents research seeking to experimentally verify the effectiveness of a thermal switch used in series with thermoelectric devices for waste heat recovery for constant and variable source heat input and for variable source thermal capacitance (mass). Using an experimental setup composed serially of a fixed heat source, a variable thermal resistance air gap serving as a thermal switch, a thermoelectric device, and a heat sink, the time-averaged power output to power input ratios improved up to 15% and 30%, respectively, for constant and variable heat input in certain design space conditions. The experimental results, as supported by model predictions, suggest that the thermal capacitance of the heat source must be greater than the thermal capacitance of the thermoelectric device in order for thermal switching to improve the time-averaged power output to power input ratios of waste heat recovery systems. The results have direct application to aircraft energy harvesting.

Objectives: The Penetration Aspiration Scale (PAS), although designed for videofluoroscopy, has been utilized with flexible endoscopic evaluation of swallowing (FEES) in both research and clinical practice. The purpose of this investigation was to determine inter- and intrarater reliability of the PAS with FEES as a function of clinician FEES experience and retest interval. Methods: Three groups of 3 clinicians (N = 9) with varying FEES experience (beginning, intermediate, and advanced) assigned PAS scores to 35 swallows. Initial ratings were repeated following short-term (ie, 1 day) and long-term (ie, 1 week) retest intervals. Results: Intraclass correlation coefficients were calculated to assess interrater reliability on the first rating for each group. The coefficients were .91, .82, and .89 for the beginning, intermediate, and advanced clinicians, respectively. Overall interrater reliability across all 9 clinicians, irrespective of experience, was .85. Intraclass correlation coefficients were also calculated to assess intrarater reliability. The intrarater reliability for short- and long-term ratings was .90, .94, and .96 and .96, .97, and .94 for the beginning, intermediate, and advanced clinicians, respectively. Overall intrarater reliability across all 9 clinicians and all 3 ratings was .94. Conclusions: Excellent inter- and intrarater reliability was evidenced with the application of the PAS for FEES regardless of clinician experience and retest interval.

Very recent thermoelectric (TE) device materials improvements have pushed this technology to the cusp of usefulness in converting waste heat to electricity in a variety of applications — from automotive to aerospace. For applications where the heat loading is cyclical or non-constant, the effect of active control to maintain the source temperature at or near the peak allowable temperature while maximizing the temperature difference across a TE temporally on the overall thermoelectric efficiency is investigated. Efficiencies for constant heat loading applications that are not at near peak allowable temperatures are also investigated. The modulation of the source temperature would be achieved through the use of a ‘thermal switch’ or ‘active thermal potentiometer’ between the heat source and the thermoelectric device. Two methods are used to model the thermoelectric energy recovery system. First, an RC equivalent model is used to define the controlling factors for efficiency on a first order basis. Second, a numerical model is created to investigate the system in more detail. Both models demonstrate that maximizing the exergy of the source by maximizing its temperature during off-peak heat loadings is capable of improving the time-averaged efficiency of a thermoelectric device. For some conditions, improved time averaged efficiencies of more than 4 times are realized. Criteria defining the operation space where efficiency improvements are realized are also developed.Copyright © 2005 by ASME

The purpose of this paper is to discuss the future of adaptive structures leading towards the concept of a fully morphing aircraft configuration. First, examples are shown to illustrate the potential system-level mission benefits of morphing wing geometry. The challenges of design integration are discussed along with the question of how to address the optimisation of such a system. This leads to a suggestion that non-traditional methods need to be developed. It is suggested that an integrated approach to defining the work to be done and the energy to be used is the solution. This approach is introduced and then some challenges are examined in more detail. First, concepts of mechanisation are discussed as ways to achieve optimum geometries. Then there are discussions of non-linearities that could be important. Finally, the flight control design challenge is considered in terms of the rate of change of the morphing geometry. The paper concludes with recommendations for future work.

This study analytically investigates the behavior of a coupled, unloaded/loaded actuator–mechanism system, which is the main element of a modern adaptive structure. The analysis is performed from an energy transfer perspective. It couples the actuator to a compliant mechanism and takes into account interactions between this mechanized system and an applied load. Analytical relationships are developed that describe energy transfer between the actuator and the mechanized structure. The methodology is general and can be applied to a myriad of loaded, adaptive structure systems. Results are consistent with existing energy based techniques and provide a fundamental insight into the behavior of adaptive structure systems. It is shown that the design of such a structure must consider the interaction between these basic elements. This body of work extends existing research by developing a methodology that can be used to optimize a mechanized structure based on interactions between its driving actuator and its external load.

Solving design problems that rely on very complex and computationally expensive calculations using standard optimization methods might not be feasible given design cycle time constraints. Variable fidelity methods address this issue by using lower-fidelity models and a scaling function to approximate the higher-fidelity models in a provably convergent framework. In the past, scaling functions have mainly been either first-order multiplicative or additive corrections. These are being extended to second order. In this investigation variable metric approaches for calculating second-order scaling information are developed. A kriging-based scaling function is introduced to better approximate the high-fidelity response on a more global level. An adaptive hybrid method is also developed in this investigation. The adaptive hybrid method combines the additive and multiplicative approaches so that the designer does not have to determine which is more suitable prior to optimization. The methodologies developed in this research are compared to existing methods using two demonstration problems. The first problem is analytic, whereas the second involves the design of a supercritical high-lift airfoil. The results demonstrate that the krigingbased scaling methods improve computational expense by lowering the number of high-fidelity function calls required for convergence. The results also indicate the hybrid method is both robust and effective.

This research investigates the effect of store parameters variation on store-induced flutter and limit-cycle oscillation phenomena of an aircraft wing in the transonic regime. The primary store parameters were its mass and the chordwise location of its center of gravity. The effect of including store aerodynamics on the wing/tip store configuration was also investigated. The tip store center of gravity (c.g.) was varied and positioned at three different locations: 32.5, 40, and 50%, with respect to aerodynamic tip chord. Automated Structural Optimization System and Computational Aeroelasticity Program‐Transonic Small Disturbance were used in the linear and nonlinear region to perform this research. Studies showed that flutter speed increases as the store c.g. was moved forward toward the leading edge. This gives an indication that store c.g. must be placed as far forward as possible with respect to the elastic axis to delay the occurrence of flutter, while satisfying other design constraints. It was observed that the increase in tip store mass significantly reduced the flight operating speed range of the aircraft. The effect of inclusion of store aerodynamics for different wing/store configurations was found to be insignificant compared to their corresponding mass-only models in the transonic regime. The limit-cycle oscillation (LCO) onset speed was found to be sensitive to both store mass and store c.g. parameters and varied significantly for different store mass configurations. The LCO onset speed decreased significantly with increase in store mass and aft movement of store c.g.

The use of large-area aerodynamic control schemes to enable high-altitude long-endurance sensor platforms is investigated. The focus is on a vehicle with a joined-wing design. The vehicle has two performance shortcomings that are considered typical of the broader class of high-altitude long-endurance vehicles. The first is minimum roll rate at landing due to the large amount of roll damping associated with these configurations. It is shown that multiple distributed control surfaces can help meet the roll rate requirements. The second is sensitivity of takeoff gross weight to maximum lift-to-drag ratio. Notional mission requirements drive the fuel fraction to high levels and small changes in lift-to-drag ratio can enable large changes in the vehicle weight through reduced fuel requirements. It is shown that the same technology used to satisfy the roll requirement can also be used to actively control the twist and camber during cruise and can have a moderate impact on the vehicle weight or endurance.

This paper presents and discusses the wind tunnel results obtained during Phase 1 and Phase 2 of the Smart Wing program. A series of four tests was conducted, two in each phase. The purpose of the tests was to evaluate the performance of smart material based control effectors in representative aerodynamic environments. In Phase 1, wing twist using a Shape Memory Alloy (SMA) torque tube and smoothly contoured trailing edge surfaces enabled by SMA wires were evaluated on a semi-span, 16% scale model of a typical fighter wing. The focus of Phase 2 was to address the design and demonstration of a high-frequency, large-deflection, and smoothly contoured trailing edge control surface capable of a spanwise variation in deflection. The actuation system for this control surface was based on piezoelectric (PZT) ultrasonic motors. A smoothly contoured leading edge control surface was also built and tested using SMA wires. These designs were evaluated on a 30%, full-span model of a representative Unmanned Combat Air Vehicle (UCAV). In each wind tunnel entry comparisons were made to the performance of conventional control surfaces. Successful results included: improved aileron effectiveness at high dynamic pressures; demonstrated improvements in lateral and longitudinal control effectiveness with smoothly contoured control surfaces over conventional hinged control surfaces; continuous spanwise shape control; and, large deflections at rates over 80°/s, which is well within the desired deflection aileron rates for control of fighter aircraft.

Investigations are conducted on lifting surfaces with conventional and conformal trailing-edge control surfaces. The Sohngen inversion formula is used with the thin-airfoil integral equation to determine the aerodynamic pressure for various control surface chord-to-airfoil chord ratios. Comparisons to a conventional control surface show increases in lift and pitching moment of the airfoil with a conformal control surface. Aerodynamic pressure distributions acting on a wing with control surfaces are determined with the vortex lattice technique. Predicted aerodynamic pressures and roll moments are compared to available wind-tunnel data and provide a more general understanding of theaerodynamicbehavior observed there. Roll performance of a rectangular wing is determined for various control surface chord-to-wing chord ratios. It is found that the maximum roll rate is greater for a wing with a conformal control surface, but has a lower reversal dynamic pressure than the wing with a conventional control surface. The aerodynamic and aeroelastic results obtained from this investigation provide some insight for wings designed with conformal control surfaces.

The fatigue response of an eight-ply, unidirectional, titanium-based metal-matrix composite (MMC) (SCS-6/Ti-15-3) was investigated at elevated temperature (427 °C) using a hybrid strain-controlled loading mode. This hybrid control mode did not allow the thin MMC specimen to experience any compressive stress and, thus, prevented buckling. All fatigue testing was conducted at a constant strain rate of 0.2% s −1 . Damage mechanisms were systematically identified for the cases when loading was parallel or perpendicular to the fiber direction. When the fibers were parallel to the loading direction, the dominant damage mechanism was either fiber fracture or matrix cracking. Matrix creep occurred at all levels of strain, and matrix plasticity was observed when the strain level was greater than 0.55%. When loading was perpendicular to the fiber direction, the fiber-matrix interfacial damage was the dominant damage mechanism. The severity of this damage varied depending upon the maximum strain level. Matrix cracks also had a critical effect on the fatigue response when the maximum strain level was greater than 0.35%. Plastic deformation in the matrix material occurred for strain levels greater than 0.23%, and matrix creep was a key factor at all strain levels. Fatigue-life diagrams along with dominant deformation and damage mechanisms were established for both cases and are compared with previous studies.

The most critical issue to organ transplantation is the identification of new sources of organs. The present manuscript illustrates the state-of-the-art regenerative medicine (RM) investigations aiming to manufacturing abdominal organs for transplant purposes.This manuscript focuses on research in the bioengineering and regeneration of kidneys, insulin-producing cells, livers and small bowel. The main technology currently under development exploits the seeding of cells on supporting scaffolding material. Despite favorable preliminary results obtained with relatively simple, hollow organs, when more complex organs are considered, the scenario changes dramatically. Investigations are still in early stages, and clinical translation is not yet foreseeable based on current knowledge and information. Obstacles are numerous but we believe the critical factor hampering success is lack of in-depth understanding of the extracellular matrix (ECM) and cell-ECM interactions, as well as the mechanisms with which organs develop in utero.The success of RM to generate transplantable abdominal organs relies heavily on progress in (stem) cell therapies, developmental and ECM biology, and in the thorough understanding of the intricate relationship and interplay between cells and the ECM. This will require enormous investments in financial and medical resources, which ideally should be embarked upon by governments, the private sector and academia.

Immunoisolation refers to an immunological strategy in which nonself antigens present on an allograft or xenograft are not allowed to come in contact with the host immune system, and it is implemented to prevent allorecognition and avoid immunosuppression. In this setting, the two most promising technologies, encapsulation of pancreatic islets (EPI) and immunocloaking (IC), are used. In the case of EPI, islets are inserted in capsules that, allow exchange of oxygen, nutrients and other molecules. In the case of IC, a natural nanofilm is injected prior to renal transplantation within the vasculature of the graft with the intent to pave the inner surface of the vascular lumen and camouflage the antigens located on the membrane of endothelia cells. Significant progress achieved in experimental models is leading EPI and IC to clinical translation.

The World Health Organization calculates that over – six hundred and fifty million people worldwide suffer of some form of liver disease, including thirty million Americans. On a worldwide base, approximately one to two million deaths are accounted to liver related diseases annually. Around the globe, China has the world’s largest population of Hepatitis B patients (approx. 120 million) with five hundred thousand people dying of liver illnesses every year (CDC, 2007; WHO, 2008). In the US alone, five hundred thousand critical liver problem episodes are reported every year requiring hospitalization with great burden to the patients and a huge cost to the health care system. In the European Union and United States of America alone, over eighty one thousand and twenty six thousand people died of chronic liver disease in 2006, respectively (CDC, 2007; Eurostat, 2007). In these patients, liver transplantation is presently the only proven therapy able to extend survival for end-stage liver disease. It is also the only treatment for severe acute liver failure and to some forms of inborn errors of metabolism.

Demand is increasing for esthetic restorations in pediatric dentistry. When full coverage is indicated, one option is to use esthetic stainless steel crowns (SSCs). However, this type of crown is prone to fracture. The purpose of this study was to evaluate the fracture resistance of 3 types of esthetic SSCs.Esthetic SSCs for first primary mandibular molars were cemented to idealized epoxy dies with glass ionomer cement. The die-crown units were fractured on a universal testing machine. The force was delivered by a stainless steel ball fixture, set in a uniaxial lever to replicate a cusp contact, with a crosshead speed of 1 mm/min. The differences among the 3 types of crown, in terms of force required to fracture, were compared statistically by 1-way analysis of variance. Pairwise comparisons were performed with Fisher's protected least significant difference test, at an overall significance level of 5%.The force required to fracture, expressed as average ± standard error, did not differ significantly among the 3 brands of esthetic SSCs: 1730 N ± 50 N, 1826 N ± 62 N and 1671 N ± 68 N, respectively (p = 0.19), well below the maximum bite force of pediatric patients determined in a previous study.Esthetic SSCs should be able to resist occlusal forces over short clinical periods. However, long-term occlusal loading and fatigue failures should be taken into account when evaluating the success of this type of crown.

Background: Emergency departments (EDs) in teaching hospitals have competing goals of timely patient care and supervised trainee education. Previous investigations have indicated that trainees add time to the length of ED patient encounters. However, no studies have quantified the effect of trainees on pediatric ED length of stay (LOS). Objectives: The objectives were to measure the effect of trainees on pediatric ED LOS by comparing LOS for patients managed by a pediatric emergency physician (PEP) alone to LOS for patients seen by a trainee and a precepting PEP (Trainee+PEP). A secondary objective was to identify factors other than provider type associated with LOS differences observed in teaching hospital pediatric EDs. Methods: Data were extracted from a computerized ED tracking system in an urban tertiary care children’s hospital with approximately 52,000 visits annually. All patients were seen by a PEP alone, an urgent care physician, or a trainee (a pediatric emergency medicine fellow; a pediatric, emergency medicine, or combined internal medicine ⁄pediatrics resident; or a medical student) plus a precepting PEP. The primary comparison was the ratio of median LOS for the PEP group versus the Trainee+PEP group. Results: There were 92,193 visits eligible for inclusion over a 2-year period. Median patient age was 5.75 years (interquartile range [IQR] = 21 months to 12.9 years). The PEP group managed 9,141 patients (10%), while the Trainee+PEP group treated 72,135 patients (78%). Overall LOS for an ED visit was 221 minutes. The median LOS was 192 minutes for PEP patients and 225 minutes for Trainee+PEP patients (difference of means = 17%, p < 0.001). Laboratory and imaging studies were associated with LOS increases of 111 and 74 minutes, respectively; both were performed more frequently in Trainee+PEP patients (44% vs. 33% for laboratory studies and 41% vs. 39% for imaging studies, both comparisons p < 0.001). When LOS was analyzed after adjusting for confounding factors including patient acuity, laboratory or radiologic testing, and trainee year, LOS for Trainee+PEP was higher by 17 minutes, or 9% (95% confidence interval [CI] = 6% to 12%, p < 0.001). When LOS was examined for four specific diagnoses (asthma, gastroenteritis, appendicitis, foot ⁄ankle sprain), there were no significant differences in LOS between the PEP and Trainee+PEP groups. Conclusions: In the pediatric ED of a teaching hospital, ED LOS is on average 9% higher in patients seen by trainees. In an era of increasing efforts to accelerate throughput while training future providers, these findings provide an important metric for the delivery of pediatric emergency care. ACADEMIC EMERGENCY MEDICINE 2009; 16:859‐865 a 2009 by the Society for Academic Emergency Medicine

This paper presents current progress in the development of semantic data integration environment which is a part of the Biomedical Informatics Research Network (BIRN; http://www.nbirn.net) project. BIRN is sponsored by the National Center for Research Resources (NCRR), a component of the National Institutes of Health (NIH). A goal is the development of a cyberinfrastructure for biomedical research that supports advance data acquisition, data storage, data management, data integration, data mining, data visualization, and other computing and information processing services over the Internet. Each participating institution maintains storage of their experimental or computationally derived data. Mediator-based data integration system performs semantic integration over the databases to enable researchers to perform analyses based on larger and broader datasets than would be available from any single institution's data. This paper describes recent revision of the system architecture, implementation, and capabilities of the semantically based data integration environment for BIRN.

This paper describes the development of a mechanized wing concept for a perching micro air vehicle. The wings are capable of rotating in pitch at two spanwise joints to simulate the motion of a bird’s wings during a perching maneuver. This project focuses on the wing mechanization design and analysis as well as the structure/mechanism integration. The advantage of a perching type of landing is that it allows the vehicle to land with approximately zero vertical and horizontal velocity on a tree branch, power line, or ledge. The requirements to perform this maneuver were investigated, the structural design was developed, and the mechanization integration to achieve this motion was determined. A model was designed and manufactured to demonstrate the kinematic mechanism making this wing motion possible. Wind tunnel testing and analytical simulation were also completed to further develop the model.

The overarching goal of the NIF (Neuroscience Information Framework) project is to be a one-stop-shop for Neuroscience. This paper provides a technical overview of how the system is designed. The technical goal of the first version of the NIF system was to develop an information system that a neuroscientist can use to locate relevant information from a wide variety of information sources by simple keyword queries. Although the user would provide only keywords to retrieve information, the NIF system is designed to treat them as concepts whose meanings are interpreted by the system. Thus, a search for term should find a record containing synonyms of the term. The system is targeted to find information from web pages, publications, databases, web sites built upon databases, XML documents and any other modality in which such information may be published. We have designed a system to achieve this functionality. A central element in the system is an ontology called NIFSTD (for NIF Standard) constructed by amalgamating a number of known and newly developed ontologies. NIFSTD is used by our ontology management module, called OntoQuest to perform ontology-based search over data sources. The NIF architecture currently provides three different mechanisms for searching heterogeneous data sources including relational databases, web sites, XML documents and full text of publications. Version 1.0 of the NIF system is currently in beta test and may be accessed through http://nif.nih.gov.

This paper describes the development of a mechanized wing concept for a perching micro air vehicle. The wings are capable of rotating at two spanwise joints to simulate the motion of a bird’s wings during a perching maneuver. This project focuses on the wing mechanization design and analysis as well as the structure/mechanism integration. The advantage of a perching type of landing is that it allows the vehicle to land with approximately zero vertical and horizontal velocity on a tree branch, power line, or ledge. The requirements to perform this maneuver were investigated, the structural design was developed, and the mechanization integration to achieve this motion was determined. A model was designed and manufactured to demonstrate the kinematic mechanism making this wing motion possible. Wind tunnel testing and analytical simulation were also completed to further develop the model.