bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved Proper Orthogonal Decomposition Technique for the Solution of a 2-D Rotor Blade Inverse Design Problem Using the Entropy Generation Rate as the Objective Function
Authors: Panzini G. , Sciubba E. , Zoli-Porroni A.
Published: May 2009

This paper discusses the optimization of a 2D rotor profile attained via a novel inverse-design approach that uses the entropy generation rate as the objective function. A fundamental methodological novelty of the proposed procedure is that it does not require the generation of the fluid-dynamic fields at each iteration step of the optimisation, because the objective function is computed by a functional extrapolation based on the Proper Orthogonal Decomposition (POD) method. With this new method, the (often excessively taxing) computational cost for repeated numerical CFD simulations of incrementally different geometries is substantially decreased by reducing much of it to easy-to-perform matrix-multiplications: CFD simulations are used only to calculate the basis of the POD interpolation and to validate (i.e., extend) the results. As the accuracy of a POD expansion critically depends on the allowable number of CFD simulations, our methodology is still rather computationally intensive: but, as successfully demonstrated in the paper for an airfoil profile design problem, the idea that, given a certain number of necessary initial CFD simulations, additional full simulations are performed only in the “right direction” indicated by the gradient of the objective function in the solution space leads to a successful strategy, and substantially decreases the computational intensity of the solution. This “economy” with respect to other classical “optimization” methods is basically due to the reduction of the complete CFD simulations needed for the generation of the fluid-dynamic fields on which the objective function is calculated.
Thermal Analysis of MEMS Actuator Performance
Authors: Machiraju Harita , Infantolino Bill , Sammakia Bahgat , Deeds Michael
Published: May 2009

A MEMS based device consisting of microactuators was modeled using finite element analysis. The temperature profile of the complete package was obtained and compared to experimental measurements. Good agreement was found between the modeling and measurements. Parametric studies of potential design parameters of the chip package to decrease the power requirements to the actuators have been studied. Increasing the gap between the handle layer and the device layer of the SOI (silicon on insulator) chip from 2 to 3 microns resulted in a reduction of 10% (0.2 Watts) per beam of the actuator. A glass top chip proved to be better at reducing the power requirements for the actuators when compared to a silicon top chip. Modeling shows that relief cuts in the substrate had a larger effect on the power reduction compared to those on the top chip since the heat conduction path to the substrate is a lower resistance path. The power reduction was as high as 50% (1.1 Watts) per beam of the actuator, when the relief cut in the substrate was 50 microns.
Computational Fluid Dynamics (CFD) Within Undergraduate Programs
Authors: Shollenberger Kim A.
Published: May 2009

There has been a rapid increase over the past three decades in the use of computational fluid dynamics (CFD) analysis by industry as a tool to design and manufacture products. It is currently a vital part of the engineering process for many companies around the world, and utilized in nearly every manufacturing industry. Employers of engineering students who perform this type of analysis have expressed the need for students at the undergraduate or B.S. level to have some CFD experience. As a result, engineering programs in the United States have begun to respond to this need by developing new curriculum and by exposing students to the use of CFD for research. The level of incorporation and implementation of CFD into the undergraduate curriculum and research at institutions varies widely. The objective of this paper is to conduct a survey of the current use of CFD in the undergraduate curriculum within mechanical engineering departments in the United States. Twenty ABET accredited U.S. schools that offer a B.S. degree in mechanical engineering are investigated in this study that are a representative sample of engineering schools in the U.S. today in terms of admission standards, private versus public, predominate terminal degree, size, and geographic location. Topics investigated include if CFD classes are offered to undergraduates whether they are required or optional, when they are first introduced into the curriculum, number of credit hours dedicated to CFD, types of courses that include CFD, and whether commercial or in-house codes are utilized.
Adaptive and Repetitive Control for Rejecting Repeatable and Non-Repeatable Runout in Rotating Devices
Authors: Pe´rez Arancibia Ne´stor O. , Lin Chi-Ying , Tsao Tsu-Chin , Gibson James S.
Published: May 2009

This paper presents a control scheme for rejecting both repeatable and non-repeatable runout components of disturbances occurring in rotational devices. To exemplify this method, implementation and experimental results for track following control of a computer hard disk drive (HDD) read/write heads are presented. Aiming for high performance, the control design involves two steps. The first is the design and tuning of a recursive least-squares (RLS) based scheme intended to achieve minimum variance performance. The second step integrates repetitive and adaptive control schemes in a real-time implementation to compensate for variations and changes in the disturbance dynamics. The repetitive part of this controller targets specific periodic disturbances. The adaptive part compensates for broad bandwidth stochastic disturbances. The key element in this design is the formulation of an appropriate optimization problem, solvable recursively by applying recursive adaptive algorithms. Experimental results obtained from the implementation of this method in a commercial HDD demonstrates the effectiveness of this approach.
High-Accuracy Intelligent Complex System by Using Electronic Parallel Datum
Authors: Xiong Xiang-Wen , Wynn Bear L.
Published: May 2009

The method of electronic parallel datum is to calculate by a stereo angle between the two beams of light with inclination simulating parameters of an object and successfully replace the 6-DOF mechanical datum of the work piece by being pre-set in the work piece and system. This technique called electronic parallel datum method has high precision for the adoption of Scan & Micro-Staggered method; furthermore, the intelligent direct reading of 6-DOF mechanical datum and parameter storage function of the technique can greatly improve the performance of the system and at the same time offer the process control method and can be used for micro-fabrication and Micro-Manufacturing and general industrial (In particular, it can be used for Ultra precision manufacturing environment, because the diameter of the laser beam can reach 100 nm and ion beam diameter even reached the limit precision of 2nm, and optical emission types, including the ion beam, Universal laser beam and general light beam, which mainly use receiver spacing of nano-array CCD sensors). It is widely used in the intelligent control process and system such as installation and adjustment, and undoubtedly, is to be adopted in many technical fields, general Manufacturing and all general work piece, precise testing process. With the method the system will become more precise, run faster and cost less.
Guidelines for Controlling Pore Radii From Nonlinear Analysis of a Two-Dimensional Model of Electroporation
Authors: Cranford Jonathan P. , Zhao Xiaopeng , Krassowska Wanda
Published: May 2009

Electroporation, in which strong electric pulses create transient pores in the cell membrane, is commonly used as a method for delivering molecules into cells. One of the pulsing protocols used in practice, a two-pulse protocol, creates a certain number of pores (Num) with a short, large electric pulse, and then controls the pore size with a second, smaller electric pulse of strength V0. This study uses nonlinear analysis of an electroporation model to determine guidelines for the magnitude of V0 and Num that will produce pores of a desired radius (r). Analysis reveals that for Num between 85 and 3190, number and type of fixed points (FPs) depend on Num and V0. For this range of Num, there exist two stable FPs and one unstable FP, and increasing V0 beyond a certain threshold (V0th) drives the system to the FP with larger r. V0th can be fit to a function that is linearly dependent on Num. This study shows that for a given Num created by the first pulse, choice of V0 will allow the experimenter to optimize pore size for a specific application.
A Study on Clay Particle Effect to the Mechanical Properties of Pultruded Composites Under Shear Loading
Authors: Park J. Y. , Fay T. , Davis T.
Published: May 2009

A micromechanical investigation aimed at examining the mechanical behavior of pultruded polymer composites containing hexagonal platelet shaped fillers under shear loading is presented. Micromechanical models that account for the presence of inhomogeneities such as the clay fillers and voids in matrix materials were developed to estimate the inplane shear properties. The analytical results were obtained based on the consideration of shape effect of filler and void, and then were compared with the properties determined by an experimental program. For the experiments, pultruded polymer composites containing clay fillers and voids as well as E-glass fiber and vinylester resin were selected, analyzed and tested under shear loading. The effects of the volume fractions of the constituents on the mechanical properties of the composites were also investigated.
On the Application of Extended Kalman and Continuous Discrete Extended Kalman Filter for a HIL Magnetic Levitation Device
Authors: Henley John A. , Shiakolas Panos S. , Subbarao Kamesh
Published: May 2009

Magnetic levitation (maglev) devices have been extensively studied in the literature and find applications in many engineering fields. In this manuscript, we investigate and discuss the control and state estimation for a nonlinear maglev device based on Kalman estimation theory considering unmodeled process and measurement noise in the formulation. The Continuous Discrete Extended Kalman Filter (CDEKF) is utilized to estimate the system states and subsequently generate the control output based on the estimates. The approach is demonstrated in simulation using actual hardware (maglev and sensor) dynamics and parameter values. Currently, the proposed approach is being implemented and tuned on hardware in the loop (HIL) maglev device. The performance of the proposed approach in the simulated environment for state estimation and system control for step and sinusoidal reference trajectories and the HIL implementation procedure are also discussed.
Moment and Friction Force in Three Dimensional Elastic Contact of Two Rectangular Rough Surfaces
Authors: Sepehri A. , Farhang K.
Published: May 2009

It is reasonable to expect that when two nominally flat rough surfaces are brought into contact by an applied resultant force, they must support, in addition to the compressive load, an induced moment. The existence of a net applied moment would imply non-even distribution of contact force so that there are more asperities in contact over one region of the nominal area. In this paper we consider the contact between two rectangular rough surfaces that provide normal and tangential contact force as well as contact moment to counteract the net moment imposed by the applied forces. The surfaces are permitted to develop slight angular misalignment and through this contact moment is derived. Through this scheme it is possible to also define elastic contribution to friction since the half-plane tangential contact force on one side of an asperity is no longer balanced by the half-plane tangential force component on the opposite side. The elastic friction force however is shown to be of a much smaller order than the contact normal force.
Nonlinear Analysis and Design Investigation of a Negative Poisson’s Ratio Material
Authors: Liu Yuanyuan , Ma Zheng-Dong
Published: May 2009

An engineered Negative Poisson’s Ratio (NPR) material is investigated in this paper for its design variations based on two design variables. The investigated material properties include effective Young’s modulus, Poisson’s ratio, material density, and load-bearing efficiency in terms of rigidity/weight ratio of the material. Nonlinear behaviors of the design variations are also investigated for large deformation applications. It is seen that by varying the two design variables, the NPR can reach as low as minus sixty in a special design. Any NPR number between a positive number and minus sixty can be obtained within the design domain through the design process. The nonlinear analysis results show that the effective material properties vary depending on the load amplitude, and the NPR material becomes stiffer and stiffer when the compression load is increased. The finite element method is utilized with a multi-step linearization method to predict the nonlinear behaviors of NPR materials. This will allow the effective material properties to be calculated for any given load amplitude. The new capability can be then used to design desired NPR material in a function-oriented material design (FOMD) environment for advanced application development. Both linear and nonlinear analysis results are presented and compared in this paper in order to demonstrate the necessity of accounting for geometric nonlinearity in the NPR material design process. An NPR material simulation and design system, called FOMD-NPR, has also been developed at MKP Structural Design Associates, Inc. for designing innovative NPR materials for various applications.
On the Numerical Scheme to Solve a Realistic Chemical Vapor Infiltration Reactor Model
Authors: Kamel John K. , Paolucci Samuel
Published: May 2009

We describe the general mathematical model as well as the numerical integration procedure arising in modeling a realistic chemical vapor infiltration process. The numerical solution of the model ultimately leads to the solution of a large system of stiff differential algebraic equations. An operator splitting algorithm is employed to overcome the stiffness associated with chemical reactions, whereas a projection method is employed to overcome the difficulty arising from having to solve a large coupled system for the velocity and pressure fields. The resulting mathematical model and the numerical integration scheme are used to explore temperature, velocity, and concentration fields inside a chemical vapor infiltration reactor used in the manufacturing of aircraft brakes.
New Insights on the Override Control Problem
Authors: Villota Elizabeth , Jayasuriya Suhada
Published: May 2009

This paper considers the override (OR) control strategy, employed for systems possessing limits on the plant variables (states and output). The aim of this work is to analyze the OR control problem on the basis of the well studied anti-windup (AW) control problem in order to facilitate transparency and systematization in the OR control system design. The performance objective related to the OR control problem is first defined and a general structural representation for OR control, comprising potential static and dynamic configurations as special cases, is then presented. The effect of OR control on the closed-loop is evaluated in terms of a general framework, termed conditioning of the plant, which permits the unification and comparison of all OR control schemes. A difference system describing the mismatch between the OR control system and the ideal output constrained system responses is further employed for comparison of OR control schemes and for synthesis of compensators as it readily quantifies the OR control objective. Finally, an optimal LMI-based optimization method for designing static OR controllers is provided and the resulting performance of the design strategy is shown by a simulation example.
Nondestructive Characterization of Composite Sandwich Materials Under Fatigue Loading
Authors: Ayorinde Emmanuel , Deng Feizhong , Chungag Godwin , Soni Samikumar
Published: May 2009

Applications of sandwich composite materials are constantly increasing to many more civilian and military areas, and they have become quite important for the construction of many structures. In this work the application of basic and reliable NDE methods to the characterization of sandwich materials suitable for marine applications has been explored. Vibroacoustic methods have been utilized, with emphasis on vibration and acoustic emission methods, on account of their rapidity of use, and reliability where applicable. Composite sandwich materials with both carbon-based and glass-based composite facings have been tested statically and in bending fatigue. The progress of damage-indicative characteristics with fatigue life has been followed with these methods from the unfatigued state. Usual vibration and acoustic emission parameters and, more informatively, those based on new joint time-frequency and wavelet transforms, are utilized to effectively characterize the materials with advancing damage under low-cycle fatigue loading. This approach was shown to be quite reliable.
Efforts in Maintaining Currency in Engineering and Avoiding Obsolescence
Authors: Miles David J. , Kreiner Jesa H.
Published: May 2009

Updating ones professional skills, continuing education and the ability to work successfully in multidisciplinary environments have become increasingly critical to staying competitive in the face of rapid advances in technology and the current trends toward outsourcing of engineering jobs. Mechanical engineers, specifically, are continuously confronted with staying current with proficiency in CAD and FEA tools, evolving multiplicity of design materials and increased sophistication of design components, as are their capabilities in communicating with both engineers and non-engineers. A survey conducted of engineering alumni of the California State University, Fullerton indicates how its graduates pursue the complex task of staying current and the degree of successes achieved in this never ending endeavor. The survey evaluated ways and means of these efforts and the employers’ attitudes and support, or lack thereof, towards such efforts, experiences of working in multidisciplinary and multi national teams and attitudes towards community service. Relationships between continued education and career are examined. Implications of the findings to engineers, education and industry are discussed. Roles that educational institutions and professional societies play in this process are carefully examined and discussed.
Nano-Cryosurgery: A Basic Way to Enhance Freezing Treatment of Tumor
Authors: Liu Jing , Yan Jing-Fu , Deng Zhong-Shan
Published: May 2009

Cryosurgery is a minimally invasive clinical technique with controlled destruction of target tissues through a specifically administrated freezing procedure. This method has now been used in a wide variety of clinical situations such as treatment of skin cancers, glaucoma, lung and prostate tumor etc. However, there still exist many bottle necks to impede the success of a cryosurgery. A most critical factor has been that insufficient or inappropriate freezing will not completely destroy the target tumor tissues, which as a result may lead to tumor regenesis and thus failure of treatment. Meanwhile, the surrounding healthy tissues may suffer from serious freeze injury due to unavoidable release of a large amount of cold from the freezing probe. To resolve this difficulty, we proposed an innovative strategy, termed as nano-cryosurgery, to significantly improve freezing efficiency of a conventional cryosurgical procedure. The basic principle of this protocol is to inject functional solution with nano particles into the target tissues, which then serves as either to maximize the freezing heat transfer process, regulate freezing scale, modify ice-ball formation orientation or prevent the surrounding healthy tissues from being frozen. Meanwhile, introduction of nanoparticles during cryosurgery could also help better image the edge of a tumor as well as the margin of the iceball. Along this direction, several progresses have been made on mechanism interpretation, theoretical modeling, numerical prediction, conceptual experimental demonstration and treatment planning etc. in the authors’ lab. This study is dedicated to present a preliminary outline on the nano-cryosurgery by summing up the aspects as mentioned above. The evident merits and shortcomings of the nano cryosurgery will be illustrated. Some potential feasibility, versatile applications and possible challenges when nanotechnology meets cryosurgery will be pointed out. It is expected that the concepts of nano-cryosurgery may suggest new opportunities for realizing a highly safe, targeted and accurate freezing therapy in future tumor clinics.
Numerical Investigation of Tandem Airfoils for Subsonic Axial-Flow Compressor Blades
Authors: McGlumphy Jonathan , Ng Wing-Fai , Wellborn Steven R. , Kempf Severin
Published: May 2009

The tandem airfoil has potential to do more work as a compressor blade than a single airfoil without incurring significantly higher losses. Although tandem blades are sometimes employed as stators, they have not been used in any known commercial rotors. While the long-term goal for this program is development of a commercially viable tandem rotor, this paper discusses tandem airfoils in subsonic, shock-free rectilinear cascade flow. Existing literature data on tandem airfoils in rectilinear cascades have been compiled and presented in a Lieblein loss versus loading correlation. Large scatter in the data gave motivation to conduct an extensive 2-D CFD study evaluating the overall performance as a function of the relative positions of the forward and aft airfoils. CFD results were consistent with trends in the open literature, both of which indicate that a properly designed tandem airfoil can outperform a comparable single airfoil on- and off-design. The general agreement of the CFD and literature data serves as a validation for the computational approach.
Parison Dimension Prediction in Extrusion Blow Molding Using Neural Network Approach: A New Strategy
Authors: Huang Han-Xiong , Li Dong
Published: May 2009

As the plastics extrusion blow molded parts are getting more and more complex, it is necessary to optimize the parison dimension distribution. Predicting the parison dimension distribution is useful to optimize the thickness distribution and property of the final part. The dependency between parison dimensions and materials characteristics, processing conditions, and die geometry is a highly nonlinear and fully coupled one. In this work, diameter and thickness swells of the high-density polyethylene parison extruded under different flow rates were obtained by a well-designed experiment. The obtained data were then used to train and test the artificial neural network (ANN) model. Trained and tested ANN model can be used to predict the dimensions at any location on the parison within a given range.
Effects of Pressure and Channel Depth on Desorption in Microscale Fractal-Like Branching Heat Exchangers
Authors: Apreotesi Mario , Mouchka Greg , Davis Keith , Tulchinsky Alex , Pence Deborah
Published: May 2009

Desorption in micro-scale plate heat exchangers having a branching flow network is investigated as a function of oil flow rate, solution flow rate, manifold pressure and channel depth. The solution is an aqueous-ammonia solution with an inlet concentration held fixed at 30%. Mass flow rate and ammonia mass fraction of the generated vapor stream are characterized as is the heat exchange effectiveness of the various heat exchange desorbers. The effects of operating or exit plenum pressure and channel height on desorption and heat transfer characteristics are considered. Microscale channels are employed for enhanced heat and mass transport. The branching nature of the flow network is employed for flow symmetry and low pressure drop penalties. An operational model is generated to correctly size and efficiently integrate the desorber into an absorption cycle.
Experimental and Numerical Studies of S2-Glass Fiber/Toughened Epoxy Composite Beams Subject to Drop-Weight or Ballistic Impact
Authors: Sevkat E. , Liaw B. M. , Delale F. , Raju B. B.
Published: May 2009

A combined experimental and 3-D dynamic nonlinear finite element approach was adopted to study composite beams subject to drop-weight or ballistic impact. The composite specimens, made of S2 glass-reinforced toughened epoxy (44% fiber volume fraction, cured at 350°F), had 24 layers (approximately 6.35 mm) with various stacking sequences. They were damaged by impacts using either an Instron-Dynatup 8520 instrumented drop-weight impact tester (low-velocity impact) or an in-house high-speed gas gun (ballistic impact). For both types of tests, the time-histories of dynamic strains induced during impact were recorded using strain gages mounted on the front and back of the composite beam specimen. For drop-weight impact tests, the time history of impact force was also recorded; whereas for ballistic impact tests, only the impact velocity was calculated from the recorded change in voltage outputs, which resulted from the traversing of the impactor through two optical paths formed by two sets of diode laser-amplified photo diode pairs. The commercially available 3-D dynamic nonlinear finite element software, LS-DYNA, incorporated with a proposed nonlinear anisotropic damage model, was then used to simulate the experimental results. Good agreement between experimental and FEM results can be seen from comparisons of dynamic strain and impact force histories and damage patterns. Once the proposed nonlinear anisotropic damage model was verified by experimental results, further finite element simulations were conducted to predict the ballistic limit velocity (V50) for penetration prevention.
Numerical Evaluation of Heat Transfer From a Spherical Dimple in a Flat Plate: Development of Appropriate Boundary Conditions
Authors: Alshroof O. , Reizes J. , Timchenko V. , Leonardi E.
Published: May 2009

A numerical investigation has been performed as to the feasibility of using spherical indentations in a flat plate for enhancing heat transfer in the laminar regime. An attempt to validate the calculation procedure resulted in a significant difference with previously published results, in which the inlet boundary condition was stated to be the Polhausen distribution. An investigation of the disparity lead to a study of the effects of various boundary conditions on the development of laminar boundary layers on an infinitesimally thin flat plate. In two-dimensions, regions appear in which velocities are greater than the free stream velocity (overshoot), unless the Blasius distribution is used to predict the inlet velocity in both directions. Surprisingly, although regions of overshoot occur when areas upstream and downstream of the plate are included in calculating the flow near the plate, the velocity distribution within the boundary layer is well represented by the Blasius profile for most of the plate. Outside the boundary layer the velocity distribution depends on the position and the length of the plate. Calculations in three dimensions using inlet boundary conditions developed from the two-dimensional study indicate that a single dimple does not enhance heat transfer.
Thermodynamics Analysis of a Combined Cycle Power Plant
Authors: Pava´n Feliciano , Romo Marco , Prince Juan
Published: May 2009

The present paper is a thermodynamics analysis, i.e. both energy and exergy analyses for a natural gas based combined cycle power plant. The analysis was performed for an existing 240 MW plant, where the steam cycle reduces the irreversibilities during heat transfer from gas to water/steam. The effect of operating variables such as pressure ratio, gas turbine inlet temperature on the performance of combined cycle power plant has been investigated. The pressure ratio and maximum temperature (gas turbine inlet temperature) are identified as the dominant parameters having impact on the combined cycle plant performance. The work output of the topping cycle is found to increase with pressure ratio, while for the bottoming cycle it decreases. However, for the same gas turbine inlet temperature the overall work output of the combined cycle plant increases up to a certain pressure ratio, and thereafter not much increase is observed. The exergy losses of the individual components in the plant are evaluated based on second law of thermodynamics. The present results form a basis on which further work can be conducted to improve the performance of these units.
Fabrication and Immobilization of 2D Colloidal Photonic Crystals
Authors: Asmatulu Ramazan , Kim Sejong , Bright Robin , Papadimitrakopoulos Fotis , Marcus Harris
Published: May 2009

A dielectrophoretic, DEP, force induced assembly technique was used to achieve close-packed 2D colloidal photonic crystals on a substrate. The experimental tests were conducted on 5.3 μm carboxyl fictionalized polystyrene (PS) particles at a 6 AC Voltage and 1 MHz frequency. After the crystal was completely formed at the center of electrodes, a polyacrylamide solution was added to the system to immobilize the photonic crystals.
Application of Tubes Filled With Granules for Crashworthy Design of Automobiles
Authors: Lee Dong Wook , Ma Zheng-Dong , Kikuchi Noboru
Published: May 2009

An innovative means for improving crashworthiness is to use tubes filled with a granular material to absorb energy during the process of a crash. In this paper, we will study how to use granular materials in the tubes found in the front posts of automobiles for improved safety. The focus will be on a specific design of tubes filled with a granular material. Note that granular particles can create enormous friction through their interactions; therefore a tube filled with a granular material can absorb much more crash energy than an empty tube. The application of granular materials to a crashworthiness design is very challenging but highly effective. In this paper, we will develop an analytic model based on the effective thickness theory of a tube filled with granules.
Vibration Control of a Flexible Link Manipulator Using an Array of Fiber-Optic Curvature Sensors and Piezoelectric Actuators
Authors: Gurses Kerem , Buckman Bradley J. , Park Edward J.
Published: May 2009

This paper presents a novel feedback sensing approach for actively suppressing vibrations of a single-link flexible manipulator. Slewing of the flexible link by a rotating hub induces vibrations in the link that persist long after the hub stops rotating. These vibrations are suppressed through a combined scheme of PD-based hub motion control and proposed piezoelectric (PZT) actuator control, which is a composite linear and velocity feedback controller. Lyapunov approach was used to synthesize the controller based on a finite element model of the system. Its realization was possible due to the availability of both linear and angular velocity feedback provided by a unique, commercially-available fiber optic curvature sensor array, called ShapeTape™. It is comprised of an array of fiber optic curvature sensors, laminated on a long, thin ribbon tape, geometrically arranged in such a way that, when it is embedded into the flexible link, the bend and twist of the link’s centerline can be measured. Experimental results show the effectiveness of the proposed approach.
The North Atlantic subpolar gyre regulates the spawning distribution of blue whiting (Micromesistius poutassou)
Authors: Hátún Hjálmar , Payne Mark R. , Jacobsen Jan Arge
Published: May 2009

The spawning stock of blue whiting ( Micromesistius poutassou ), an economically important pelagic gadoid in the North Atlantic Ocean, increased threefold after 1995. The reproductive success of the stock is largely determined during the very early stages of life, but little is known about the spawning dynamics of this species. Here we show that the spawning distribution of blue whiting is variable, regulated by the hydrography west of the British Isles. When the North Atlantic subpolar gyre is strong and spreads its cold, fresh water masses east over Rockall Plateau, the spawning is constrained along the European continental slope and in a southerly position near Porcupine Bank. When the gyre is weak and conditions are relatively saline and warm, the spawning distribution moves northwards along the slope and especially westwards covering Rockall Plateau. The apparent link between the spawning distribution and the subpolar gyre is the first step towards understanding the reproduction variability, which currently is the main challenge for appropriate management of the blue whiting stock.
Estimation of seal pup production from aerial surveys using generalized additive models
Authors: Salberg Arnt-Børre , Øigård Tor Arne , Stenson Garry B. , Haug Tore , Nilssen Kjell T.
Published: May 2009

In this paper, we estimate the pup production of harp seals ( Pagophilus groenlandicus ) using generalized additive models (GAMs) based on thin-plate regression splines. The spatial distribution of seal pups in a patch is modelled using GAMs, and the pup production is estimated by numerically integrating the model over a fine grid area of the patch. Closed form expression for estimation of the the standard error of the pup production estimate is derived. The estimators are applied to simulated seal populations to investigate their properties. The results show that the proposed pup production estimator is comparable with the conventional pup production estimator. However, the bias of the standard error estimator of the proposed method is much lower than the bias of the conventional standard error estimator. The decrease of standard error bias results in a considerable reduction of the coefficient of variation estimate using the proposed GAM-based method. The proposed method is also applied to real survey data of harp seals obtained from aerial surveys in the Greenland Sea pack ice in 2002. We show that the number of pups counted from aerial photographs possess a good fit to the negative binomial distribution when a logarithmic link function is applied. The approach described here is applicable to many situations where georeferenced counts or measurements are available.
Gem #26
Authors: Duff Bob
Published: May 2009

Ada Gem #26 --- T'Mod can be used to convert signed integers to modular integers using modular (wraparound) arithmetic.
MicroRNA: a new entrance to the broad paradigm of systems molecular medicine
Authors: Liang Mingyu
Published: May 2009

Systems molecular medicine is the science of combining systems biology with molecular analysis and intervention to address clinically relevant questions. MicroRNAs (miRNAs) appear particularly suitable to serve as hubs of regulatory networks underlying complex diseases. Clear experimental evidence for coordinated regulation of a large number of genes by miRNAs, however, is still rare. It leaves open several fundamental questions that are important for determining the value of miRNA in complex regulatory networks and in systems molecular medicine. Physiological genomics is a powerful approach for addressing these open questions.
Influence of Pyrolysis Parameters on the Performance of CMSM
Authors: Campo Marta C. , Visser Tymen , Nijmeijer Kitty , Wessling Matthias , Magalhães Fernão D. , Mendes Adélio M.
Published: May 2009

Carbon hollow fiber membranes have been prepared by pyrolysis of a P84/S-PEEK blend. Proximate analysis of the precursor was performed using thermogravimetry (TGA), and a carbon yield of approximately 40% can be obtained. This study aimed at understanding the influence of pyrolysis parameters—end temperature, quenching effect, and soaking time—on the membrane properties. Permeation experiments were performed withN2, He, andCO2. Scanning electron microscopy (SEM) has been done for all carbon hollow fibers. The highest permeances were obtained for the membrane submitted to an end temperature of750°Cand the highest ideal selectivities for an end temperature of700°C. In both cases, the membranes were quenched to room temperature.
Elevated Aminotransaminases As the First Manifestation of Sarcoidosis
Authors: Nawfal Georges , Budin Christelle , Bouvier Raymonde , Lachaux Alain
Published: May 2009

Sarcoidose is a rare disease in children. The aminotransaminase level is often normal to moderately elevated (2 to 3 folds of the normal level). We report the case of a child who presented an aminotransaminase level that was 10 times the normal level, as the first manifestation of sarcoidosis.
Ku Band Hemispherical Fully Electronic Antenna for Aircraft in Flight Entertainment
Authors: Catalani Alfredo , Di Paolo Franco , Migliorelli Marzia , Russo Lino , Toso Giovanni , Angeletti Piero
Published: May 2009

The results obtained in the frame of the ESA activity “Advanced Antenna Concepts For Aircraft In Flight Entertainment” are presented. The aim of the activity consists in designing an active antenna able to guarantee the Ku band link between an aircraft and a geostationary satellite in order to provide in flight entertainment services. The transmit-receive antenna generates a single narrow beam to be steered electronically in a half sphere remaining compliant with respect to stringent requirements in terms of pattern shape, polarization alignment, EIRP, G/T, and using customized electronic devices. At the same time, the proposed solution should be competitive in terms of cost and complexity.
Totally Tubeless Outpatient Percutaneous Nephrolithotomy: Initial Case Report
Authors: Beiko Darren , Samant Meghana , McGregor Thomas B.
Published: May 2009

We report the first case of totally tubeless outpatient percutaneous nephrolithotomy (PCNL). Our patient was discharged home safely less than 4 hours following uncomplicated PCNL with no nephrostomy tube, ureteral stent, or urethral catheter. Follow-up the next day in clinic confirmed that the procedure was successful, as the patient was clinically well and stone free. To our knowledge, this is the first case report of totally tubeless (no nephrostomy, no ureteral stent) PCNL performed on a truly outpatient basis.
Meeting the Challenge
Authors: Reg Bott T.
Published: May 2009

The first Chempor Conference held in Lisbon in 1975 under the auspices of the Calouste Gulbenkian Foundation, heralded a regular wide-ranging review of research and development in Portugal and the UK Progressively in later years the Conferences have attracted contributions from other European countries and indeed further afield. There is an increasing awareness of the problems for the environment, notably global warming, brought about by human activities. Recent predictions about the future are dire, particularly regarding food and water for a rapidly growing world population. They represent a substantial challenge to the scientific and technical fraternity. In response to that challenge it is important to keep up to date with technical developments, to meet and keep in touch with coworkers in associated fields, and to cooperate wherever possible. The papers presented at the Chempor and other conferences have made and continue to make a significant contribution to that objective of meeting the challenge.
Cephalic Tetanus from Penetrating Orbital Wound
Authors: Guyennet Eloïse , Guyomard Jean-Laurent , Barnay Emilie , Jegoux Franck , Charlin Jean-François
Published: May 2009

Tetanus is a neurologic disorder caused by tetanospasmin, a protein toxin elaborated by Clostridium tetani. Cephalic tetanus is a localized form of the disease causing trismus and dysfunction of cranial nerves. We report the case of a man who presented with facial trauma, complete ophthalmoplegia, exophthalmos, areactive mydriasis, and periorbital hematoma. An orbital CT revealed air bubbles in the right orbital apex. The patient was given a tetanus toxoid booster and antibiotherapy. After extraction of a wooden foreign body, the patient developed right facial nerve palsy, disorders of swallowing, contralateral III cranial nerve palsy, and trismus. Only one case of cephalic tetanus from penetrating orbital wound has been reported in literature 20 years ago. When a patient presents with an orbital wound with ophthalmoplegia and signs of anaerobic infection, cephalic tetanus should be ruled out.
Soybean Lectin Enhances Biofilm Formation byBradyrhizobium japonicumin the Absence of Plants
Authors: Pérez-Giménez Julieta , Mongiardini Elías J. , Althabegoiti M. Julia , Covelli Julieta , Quelas J. Ignacio , López-García Silvina L. , Lodeiro Aníbal R.
Published: May 2009

Soybean lectin (SBL) purified from soybean seeds by affinity chromatography strongly bound toBradyrhizobium japonicumUSDA 110 cell surface. This lectin enhanced biofilm formation byB. japonicumin a concentration-dependent manner. Presence of galactose during biofilm formation had different effects in the presence or absence of SBL. Biofilms were completely inhibited in the presence of both SBL and galactose, while in the absence of SBL, galactose was less inhibitory. SBL was very stable, since its agglutinating activity ofB. japonicumcells as well as of human group A+ erythrocytes was resistant to preincubation for one week at60°C. Hence, we propose that plant remnants might constitute a source of this lectin, which might remain active in soil and thus favorB. japonicumbiofilm formation in the interval between soybean crop seasons.
Eosinophilic Enteritis with Ascites in a Patient with Overlap Syndrome
Authors: Aslanidis Spyros , Pyrpasopoulou Athina , Soufleris Kostas , Kazantzidou Eirini , Douma Stella
Published: May 2009

Gastrointestinal involvement is frequent in patients with systemic lupus erythematosus (SLE). Eosinophilic gastroenteritis, however, has only rarely been described in rheumatological conditions, despite its reported connection to autoimmune diseases, such as hypereosinophilic syndrome, vasculitides, and systemic mastoidosis. It presents typically with abdominal pain and diarrhea and is only exceptionally associated with ascites. Diagnosis can be problematic, as several other clinical conditions (malignancies, infection/tuberculosis, and inflammatory bowel diseases) have to be ruled out. It is basically a nonsurgical disease, with excellent recovery on conservative treatment. We report the rare case of a young woman with overlap syndrome who presented with abdominal pain and ascites. The diagnosis of eosinophilic enteritis was made based on clinical, radiological, and laboratory criteria. The patient was treated with corticosteroids with excellent response.
Side-Alternating Vibration Training Improves Muscle Performance in a Patient with Late-Onset Pompe Disease
Authors: Khan Aneal , Ramage Barbara , Robu Ion , Benard Laura
Published: May 2009

Side-alternating vibration training (SAVT) was used for 15 weeks in a patient with Late-onset Pompe disease who had never used enzyme replacement or chaperone therapy. Prior to the use of SAVT, the patient had experienced declining muscle performance and her 6-minute walk distance decreased from 210 to 155 metres in 6 months. After SAVT, her 6-minute walk distance increased 70% from 166 to 282 metres, muscle jumping power increased by 64% from 83 to 166 watts, isometric knee extensor strength increased 17% from 38 to 44 Nm, and she achieved a more normal pattern of ankle, knee, and joint kinematics and kinetics. Her functional ability measured through the Rotterdam 9-item score was unchanged at 19/36. There were no elevations in serum creatine kinase or lactate. This is the first report, to our knowledge, of a performance improvement in a patient with Pompe disease using SAVT.
Use of Viscosity to Probe the Interaction of Anionic Surfactants with a Coagulant Protein from Moringa oleifera Seeds
Authors: Maikokera Raymond , Kwaambwa Habauka M.
Published: May 2009

The intrinsic viscosity of the coagulant protein was evaluated from the flow times of the protein solutions through a capillary viscometer, and the results suggested the coagulant protein to be globular. The interactions of the coagulant protein with anionic surfactant sodium dodecyl sulphate (SDS) and sodium dodecyl benzene sulfonate (SDBS) were also investigated by capillary viscometry. We conclude that there is strong protein‐surfactant interaction at very low surfactant concentrations, and the behavior of the anionic surfactants in solutions containing coagulant protein is very similar. The viscometry results of protein‐SDS system are compared with surface tension, fluorescence, and circular dichroism reported earlier. Combining the results of the four studies, the four approaches seem to confirm the same picture of the coagulant protein‐SDS interaction. All the physical quantities when studied as function of surfactant concentration for 0.05% (w/v) protein solution either exhibited a maximum or minimum at a critical SDS concentration.
Zur unterschiedlichen Verwertung von Glukose und Sorbitol bei medikamentös induzierter hyperkortikaler Stoffwechsellage
Authors: Heine W. , Krüger G. , Said M.
Published: May 2009

Die Utilisation von Glukose und Sorbitol bei intravenöser Applikation in hyperkortikalen Stoffwechselsituationen wurde an 9 Kindern im Alter von 6–13 Jahren mit Adipositas und praediabetischer Stoffwechsellage im Steroid-Glukose-Toleranz-Test (SGTT) untersucht. Unter der Infusion von Glukose stiegen die Blutglukosewerte im Durchschnitt von 103 ± 15,5 auf 388 ± 96,6 mg/l00 ml an. Der Glykämieabfall setzte im Mittel erst nach 90 min ein und war bei 3 von 9 Patienten nach 180 min noch nicht im Normbereich. Äquimolare Sorbitolmengen führten unter analogen Testbedingungen in der gleichen Patientengruppe nur zu einem mittleren maximalen Blutglukose-anstieg von 93 ± 16,6 auf 129 ± 28,7 mg/l00 ml. Im Zeitraum zwischen 2 und 180 min nach Infusionsbeginn lagen alle Blutglukosewerte im SGTT signifikant holier als unter Sorbitolbelastung. Unter der Prednisolon-Glukosebelastung wurden bis zu 4,2% Glukose im Harn ausgeschieden. Die renalen Sorbitol·verluste waren unter der Prednisolonbelastung mit ∼ 14 % der Zufuhr gleich hoch wie die Glukoseverluste unter Prednisolon-Glukose-Belastung. Die Ergebnisse der vergleichenden Prednisolon-Glukose- und Predni-solon-Sorbitolbelastung weisen auf die Vorteile der kombinierten Infusion von Glukose- und Zuckeraustauschstoffen in hyperkortikalen Stoffwechsellagen hin.