bluuebunny/crossref_metadata_2025 huggingface dataset:
Kidney diseases caused by glomerular basement membrane typeIVcollagen defects in dogs
Authors: Lees George E.
Published: March 2013

Objective

To review the pathogenesis, as well as the clinical and pathologic features of canine glomerular diseases caused by genetic typeIVcollagen defects.

Data Sources

Original studies and review articles from human and veterinary medical fields.

Human Data Synthesis

Presence in glomerular basement membranes (GBM) of a network composed of α3.α4.α5 heterotrimers of typeIVcollagen is required to maintain structure and function of glomerular capillary walls.

Veterinary Data Synthesis

Hereditary nephropathy (HN) is the most commonly used name for kidney diseases that occur in dogs due to genetic typeIVcollagen abnormalities. To date, 4 different collagenIVgene mutations have been identified in dogs withHN; 2 areCOL4A5mutations that causeX‐linkedHN(XL‐HN), and 2 areCOL4A4mutations that cause autosomal recessiveHN(AR‐HN). Affected males withXL‐HNand affected males and females withAR‐HNdevelop juvenile‐onset kidney disease manifested by proteinuria typically starting at 3–6 months of age and followed by progressive kidney disease leading to terminal failure usually at 6–24 months of age. Carrier female dogs withXL‐HNalso develop proteinuria starting at 3–6 months of age, but progressive disease causing kidney failure is uncommon until they are >5 years old. The distinctive pathologic lesions ofHNare extensive multilaminar splitting and thickening of theGBM, as demonstrated by electron microscopy, and abnormal typeIVcollagen α‐chain content of basement membranes, as demonstrated by immunolabeling. Identification of the underlying gene mutations has permitted genetic testing and selective breeding practices that currently are minimizingHNin breeds known to be at risk.

Conclusions

CanineHNis a rare disease that should be considered whenever a dog exhibits a juvenile‐onset kidney disease characterized partly by proteinuria, but highly specialized methods are required to pursue a definitive diagnosis.
Darryl E. Metzger Memorial Session Paper: Comparison of Calculated and Measured Heat Transfer Coefficients for Transonic and Supersonic Boundary-Layer Flows
Authors: Hu¨rst C. , Schulz A. , Wittig S.
Published: March 2013

The present study compares measured and computed heat transfer coefficients for high-speed boundary layer nozzle flows under engine Reynolds number conditions (U∞=230 ÷ 880 m/s, Re* = 0.37 ÷ 1.07 × 106). Experimental data have been obtained by heat transfer measurements in a two-dimensional, nonsymmetric, convergent–divergent nozzle. The nozzle wall is convectively cooled using water passages. The coolant heat transfer data and nozzle surface temperatures are used as boundary conditions for a three-dimensional finite-element code, which is employed to calculate the temperature distribution inside the nozzle wall. Heat transfer coefficients along the hot gas nozzle wall are derived from the temperature gradients normal to the surface. The results are compared with numerical heat transfer predictions using the low-Reynolds-number k–ε turbulence model by Lam and Bremhorst. Influence of compressibility in the transport equations for the turbulence properties is taken into account by using the local averaged density. The results confirm that this simplification leads to good results for transonic and low supersonic flows.
Computation and Simulation of Wake-Generated Unsteady Pressure and Boundary Layers in Cascades: Part 2—Simulation of Unsteady Boundary Layer Flow Physics
Authors: Fan S. , Lakshminarayana B.
Published: March 2013

The unsteady pressure and boundary layers on a turbomachinery blade row arising from periodic wakes due to upstream blade rows are investigated in this paper. Numerical simulations are carried out to understand the effects of the wake velocity defect and the wake turbulence intensity on the development of unsteady blade boundary layers. The boundary layer transition on the blade is found to be strongly influenced by the unsteady wake passing. Periodic transitional patches are generated by the high turbulence intensity in the passing wakes and transported downstream. The time-dependent transition results in large unsteadiness in the instantaneous local skin friction coefficient and a smoother time-averaged transition curve than the one observed in the steady boundary layer. A parametric study is then carried out to determine the influence of wake parameters on the development of the unsteady blade boundary layers. It is shown that the unsteadiness in the blade boundary layer increases with a decrease in the axial gap, an increase in wake/blade count ratio, or an increase in the wake traverse speed. The time-averaged boundary layer momentum thickness at the trailing edge of the blade is found to increase significantly for higher wake/blade count ratio and larger wake traverse speed. Increase of the wake/blade count ratio also results in higher frictional drag of the blade.
Wake-Induced Unsteady Flows: Their Impact on Rotor Performance and Wake Rectification
Authors: Adamczyk J. J. , Celestina M. L. , Chen Jen Ping
Published: March 2013

The impact of wake-induced unsteady flows on blade row performance and the wake rectification process is examined by means of numerical simulation. The passage of a stator wake through a downstream rotor is first simulated using a three-dimensional unsteady viscous flow code. The results from this simulation are used to define two steady-state inlet conditions for a three-dimensional viscous flow simulation of a rotor operating in isolation. The results obtained from these numerical simulations are then compared to those obtained from the unsteady simulation both to quantify the impact of the wake-induced unsteady flow field on rotor performance and to identify the flow processes which impact wake rectification. Finally, the results from this comparison study are related to an existing model, which attempts to account for the impact of wake-induced unsteady flows on the performance of multistage turbomachinery.
Computer Aided Design of a Pattern and Risers for Casting Processes: Part 1
Authors: Park Jong Cheon , Lee Kunwoo
Published: March 2013

An interactive computer program has been developed to design a pattern and risers for the production of castings of high quality. In our system, the user models the shape of a final product by using the system’s modeling capability, a pattern is generated in a three-dimensional model by eliminating the holes and adding shrinkage allowances and drafts, the proper riser is created automatically, and they are united together to yield a three-dimensional model of this portion of a mold assembly. The mold can be completed after the runners and the gating systems are designed, modeled, and united which will be described in Part 2 of this work. The unique feature of this work is a realization of an automatic design of the pattern and risers by integrating the modeling capabilities and the design equations used in commercial practice.
Localization of 3-D Objects Having Complex Sculptured Surfaces Using Tactile Sensing and Surface Description
Authors: Sahoo K. C. , Menq Chia-Hsiang
Published: March 2013

This paper presents a method for locating 3-D objects having complex and sculptured surfaces. Among many complex shaped objects, dies, molds, gears, turbine blades, forged parts, and aerospace structural parts are some examples of particular interest. Locating a part amounts to finding a rigid body transformation between the part coordinate frame and the machine coordinate frame. The presented method determines position and orientation of an object by minimizing the sum of the squared distances of the measurement points from the surface of the object with respect to the parameters of transformation. Tactile sensing by Coordinate Measurement Machine (CMM) has been used as the means of measurement. A criterion for selecting measurement points to avoid singularity and help achieve better accuracy of the solutions has also been discussed. Computer simulation of the algorithm has been performed on objects of various shapes and numerical problems encountered are discussed. Experimental implementation of the method for integration of the algorithm with inspection process is also illustrated.
Identification of Joint Structural Parameters Between Substructures
Authors: Kim T. R. , Ehmann K. F. , Wu S. M.
Published: March 2013

A new methodology of combining the finite element model of a complex structure with its model obtained by experimental modal analysis techniques is presented to identify the joint stiffness and the damping characteristics between its substructures. First, the modal parameters of the structure with joints are extracted based on experimental data using Autoregressive Moving Average Vector models. Then, a condensation technique based on the Riccati iteration algorithm and the orthogonality conditions is applied to reduce the matrix order of the finite element model to match the order of the experimental model. Comparing the two models, the unknown joint parameters are estimated based on the least squares method. The accuracy and the effectiveness of the proposed method were verified through simulation studies.
On the Doubly Regenerative Stability of a Grinder: The Effect of Contact Stiffness and Wave Filtering
Authors: Thompson R. A.
Published: March 2013

In the interest of acquiring a physical understanding of the causes and growth of chatter in grinders, past studies of doubly regenerative stability by the author (Thompson, 1974, 1977; Hahn and Thompson, 1977) looked at unnaturally high workpiece rotational speeds, excluded the contribution of cutting zone contact stiffness, and did not consider the effect of workpiece wave filtering. By incorporating these effects into the past referenced work, this paper attempts to close the gap between basic understanding and actual grinder behavior. It is known that at low speeds chatter involving large numbers of lobe pairs is excited. This leads to a diffuse frequency spectrum. It is further shown that the effect of finite contact stiffness is to improve stability and that workpiece wave filtering has no effect on basic stability, but leads to self-limiting chatter. The approach to wave filtered quasistability is accompanied by a lowering of chatter frequency.
A Possibility of 1/f Evaluation on Surface Finishes Based on Fluctuation Behavior
Authors: Shiraishi M.
Published: March 2013

The effectiveness of the optical method for evaluating engineering surfaces is described in terms of fluctuation properties as a means of a more global measuring technique of products. This is based on the 1/f fluctuation in which the power spectral density is proportional to the inverse of frequency f. Turned surfaces machined under different cutting conditions are tested by the reflection technique of a laser light, and its reflection intensity is analyzed to obtain the relation between the power spectral density and the spatial frequency. As a consequence, surface profiles with 1/f and 1/f1.5 properties seem to be satisfactory in conjunction with the results of sensory evaluation.
On the Wear Mechanisms and Cutting Performance of Silicon Carbide Whisker-Reinforced Alumina
Authors: Thangaraj A. R. , Weinmann K. J.
Published: March 2013

The objective of this research was to study the types of wear suffered by silicon carbide whisker-reinforced aluminum oxide inserts in the machining of Inconel 718. Further, it was desired to study the effects of tool wear and cutting conditions on cutting forces, workpiece dimensional accuracy, and surface finish. Machining tests were conducted using 12.7 mm diameter round inserts at cutting speeds ranging from 6.0 to 13.0 m/s. The feed rates ranged from 0.13 to 0.51 mm/rev and two depths of cut of 0.76 and 1.27 mm were used. Tool failure in the cutting of the relatively soft (220 HB) nickel-based superalloy was due to excessive wear. Flank wear played a larger role at the lower speeds, but depth-of-cut notch wear was significant at the higher speeds. Abrasion, adhesion, and chipping were found to be the dominant wear mechanisms. The results of this study are presented and discussed in this paper.
A Coupled Thermomechanical Approach for Hot Rolling by a 3D Finite Element Method
Authors: Montmitonnet P. , Chenot J. L. , Bertrand-Corsini C. , David C. , Iung T. , Buessler P.
Published: March 2013

A finite element model of hot rolling is described. It is based upon the flow formulation, with a Norton-Hoff purely viscoplastic behavior. We use a steady state approach with free surface updating by minimizing the material flux through the surface. To compute stresses, smoothed derivatives of the velocity are obtained and the strain rate tensor and stress deviator computed from them. Then the pressure field is calculated by a least squares method on the residual of equilibrium equations. A simplified thermal transfer equation is obtained by neglecting internal conduction. Boundary conditions include a contact temperature accounting for a thermal contact resistance and heat generated by friction. Thermomechanical coupling is performed. It is applied to simulation of a multipass blooming sequence in order to evaluate metallurgical evolution of the product. The interest of stresses computation is demonstrated for predicting surface crack opening and closing in shape rolling, with comparison to experimental trends.
Damping Capacity of Turning Tools, Part 1: Effect of Clamping Conditions and Optimum Clamping Load
Authors: Marui E. , Hashimoto M. , Kato S.
Published: March 2013

Damping capacity greatly affects the dynamic rigidity of a machine tool system. This paper deals with the damping capacity of turning tools. Damping capacity is measured as a function of clamping conditions such as clamping load or surface topography of tool shank. An empirical equation of damping capacity representing the clamping load dependence is induced for the fundamental mode of vibration in tangential and normal directions. The optimum clamping load, at which the stability of turning tool for chatter excitation becomes maximum, is experimentally clarified.
Real-Time Identification of Ill-Conditioned
Structures
Authors: Moustafa Kamal A. F.
Published: March 2013

The dynamical characteristics of structures, that could be ill-conditioned, is represented in this paper by a linear multi-degree of freedom canonical model. A time domain identification technique is suggested to estimate the mass, damping and stiffness matrices, in real-time, by using excitation-response measurement records. A singular perturbation technique is used to deal with ill-conditioning of the mass matrix. The least square method is applied to recover the unknown matrices. A numerical example is presented to verify the results. The possibility of applying the proposed technique to offshore towers is indicated.
Identification of Marine Soils by Ballistic Penetrometry
Authors: Hembise O. , Guevel P. , Bardey P. R. , Viaud J. L. , Boisson J. Y. , Vacherand F.
Published: March 2013

This article describes a disposable, sensor-filled ballistic penetrator for in-situ measurements during and after penetration into the clayey sediments of the seabed at depths of about 6000 m. The project involved work on several theoretical and experimental aspects of hydrodynamics: penetrator shape optimization, course stability, precision of point of impact. In addition, measurement and data acquisition techniques were developed using high-pressure sensors, and the dynamics of soil penetration and hole-closing were studied. The project led to the implementation of instrument-carrying devices weighing two tonnes, which, by penetrating some 40 m into the clay at impact speeds of the order of 55 m/s, provided valuable information on the physical characteristics of the seabed soils.
Multidiscipline Design Optimization
Authors: Vanderplaats Garret N.
Published: March 2013

While formal optimization techniques are seeing increasing use within individual disciplines, application of this technology to the more general multidiscipline design problem is less common. This is due to both the inherent complexity of multidiscipline design and the fact that design is traditionally separated along discipline lines. The application of optimization to multilevel and multidiscipline design is discussed here. It is seen that, computationally, multilevel design within a single discipline and multidiscipline design across disciplines have similar features, and so are generally treated the same. Multidiscipline optimization at the conceptual level is first discussed and it is seen that this has been done successfully for some time. Then the more general case is discussed where formal mathematical decomposition of the larger problem is required to make optimization practical. Here, the state of the art is still relatively undeveloped. Two basic approaches are briefly described to indicate the concepts, and a simple example is offered. The key idea in persuing the multidiscipline design problem is that the optimum system is seldom the sum of optimum components. It is necessary to properly account for the coupling that exists among the subsystems, while still allowing the individual designer to work with relative freedom within his discipline. It is concluded that to achieve this, considerable research remains ahead.
Dynamic Analysis of a Cantilever-Mounted Gas-Lubricated Thrust Bearing
Authors: Etsion I. , Green I.
Published: March 2013

The dynamic stability of a cantilever-mounted gas-lubricated thrust bearing is analyzed using the step-jump approach. The solution is based on linearization of the equations of motion assuming small perturbation about an equilibrium position. Stiffness and damping of the lubricating film are expressed analytically in terms of Laguerre coefficients thus, enabling a parametric investigation of the bearing. The general theory is used to examine an actual bearing design. It is found that the theoretical results agree with existing experimental data, in that, both show that the bearing is unstable at the design point and becomes more stable as speed decreases.
Surface Temperatures in Sliding Systems—A Finite Element Analysis
Authors: Kennedy F. E.
Published: March 2013

Finite element equations are developed for studying surface temperatures resulting from frictional heating in sliding systems. The equations include the effect of velocity of moving components, an effect which is found to be quite significant, even at low sliding velocities. A program was written using the equations and it was applied to the study of surface temperatures in two different sliding systems: dry or boundary lubricated sleeve bearings and a labyrinth gas path seal configuration. Very good agreement was achieved between analytical predictions using the program and experimental temperature measurements. The program was used to study the influence of various material parameters on surface temperatures in the two sliding systems.
Prediction of the Operating Temperature of Thrust Bearings
Authors: Vohr J. H.
Published: March 2013

An analytical method is described for predicting the operating temperature of thrust bearings of the size and speed typically found in large vertical machinery. The method involves evaluating the various mechanisms by which heat is transferred from the bearing and balancing this heat loss against the calculated heat generated by viscous shearing. This heat balance analysis is combined with a comprehensive bearing computer program which evaluates bearing pressure distributions, bearing pad deflection, lubricant flow and lubricant temperature rise within the bearing film. Predicted bearing operating temperatures show excellent agreement with laboratory tests and with field measurements over a wide range of bearing sizes and operating conditions.
Parasitic Seismic Response of Equipment in Base Isolated Structure
Mounted on Sliding Bearings
Authors: Ikonomou A. S.
Published: March 2013

All the implementations of seismic base isolation of structures until today—except for one (1982)—have used laminated rubber bearings inserted at foundation level which transfer simultaneously both horizontal and vertical forces. The double function of these bearings and the buckling problem resulting from it have led designers to restrict the fundamental period of the isolated structure to values less than 1.5–2 s in order to avoid large displacements, and this has caused a limitation of isolation efficiency. On the contrary, when the transfer of vertical forces is uncoupled from the transfer of horizontal forces, i.e., when these two functions are accomplished by independent components (for example, sliding bearings and steel or rubber springs, respectively), the buckling problem is overcome. The present study deals with equipment installed in an isolated structure mounted on such a dual support. It carries out a parameter analysis of the parasitic response of the equipment produced by horizontal friction force transferred to the structure through the sliding bearings. The parameters considered are: 1) the fundamental period of the isolated structure (1.5 to 7 s), 2) the stiffness of the sliding bearings, 3) the friction coefficient μ (2 to 15 percent), 4) the ratio σ of equipment mass to the whole structure mass (σ = 0.125 to 50 percent), 5) the frequency content of the ground seismic motion, 6) its intensity (0.3 to 3.0g GPA), and 7) the fundamental frequency of the equipment (3 to 30 Hz).
An Experimental Study of Elastic-Plastic Fracture on the Special
Shape Plate Specimen With High Strain Gradient Simulating Pressure Vessel
Nozzles
Authors: Zhao Y. , Li Z. Z. , Wang Y. P. , Zheng G. X. , Cheng G. L. , Huang Z. B.
Published: March 2013

The paper presents a special shape plate specimen with high strain gradient fields which are similar to those at pressure vessel nozzles. On the specimens, experimental J parameter was obtained by means of the multiple specimen technique; the CTOD δt of three definitions was measured with the microphotography technique; the fracture criteria of the crack initiation were examined at the same time. Thus the estimation formula of the parameter J and the relation between J and δt are deduced for practical nozzle corner cracks. The suitability of the engineering methods of defect assessment being used popularly all over the world and the problem of J controlling crack growth are discussed at the end of the paper.
Design of Fixed Tubesheet for Heat Exchangers
Authors: Paliwal D. N.
Published: March 2013

A new method of design, using the concept of equivalent solid thick plate on elastic foundation is described. Component theory that takes into account the influence of transverse shearing strain and uses more exact expressions for normal stresses, is employed. Use of more accurate values of effective elastic constants for thick plates and generalized plane strain case and the local stress multipliers due to Slot and O’Donnell [14] and Porowski and O’Donnell [15], respectively, is suggested. Effects of solid annular rim, differential expansions between tubes and shell, and interaction between tubesheet and shell/channel are also taken into account.
Design of Pressure Vessel Cascades for Electromagnetic
Launchers
Authors: Fahrenthold E. P.
Published: March 2013

The relatively recent development of very high-energy density pulsed power supplies has motivated a renewed interest in the structural design of electromagnetic launchers. Cascade design electromagnetic launcher pressure vessels offer convenient maintenance access to high wear rate components of the structure while satisfying an unusual combination of electromagnetic, strength, and preloading constraints imposed on the system designer. Analysis for design of such structures focuses on the accurate characterization of fluid-structure interaction under dynamic asymmetric loading.
Flow-Induced Instability of Heat-Exchanger Tubes due to Axial Flow in
a Diffuser-Shaped, Loose Intermediate Support
Authors: Yasuo A. , Paidoussis M. P.
Published: March 2013

In some heat exchangers and steam generators, the flow is predominantly axial, and the external fluid flows between baffled compartments through enlarged holes in the baffles around the heat exchanger tubes. Thus, the tube is subjected to relatively high flow velocities over small portions of its length, in the baffle locations. In this paper, the dynamics of such an idealized system is investigated, involving a cylindrical beam with pinned ends in axial flow, going through a baffle plate of finite thickness at some intermediate point, with small radial clearance. The fluid forces along the tube are formulated in a manner reminiscent of the transfer-matrix technique, since the character of these forces changes drastically along the tube. The fluid forces are determined approximately by means of potential flow theory, and viscous effects are taken into account only in a global sense. It was found that if the flow passage through the baffle plate is diffuser-shaped, negative fluid-dynamic damping is generated therein, destabilizing the system and leading to flutter at relatively low flow velocities. The instability depends critically on the shape of the hole through the baffle and on the clearance; thus a convergent-type flow passage does not lead to instability. The negative fluid-dynamic damping is linearly proportional to the flow velocity through the baffle.
An Investigation Into the Post-Stable Behavior of a Tube Array in
Cross-Flow
Authors: Lever J. H. , Rzentkowski G.
Published: March 2013

In the experimental determination of fluid-elastic stability thresholds in tube arrays, the critical flow velocity is normally approached from below. Once large amplitude whirling motions are initiated, however, the system often does not retrace the response curve as flow velocity is reduced. This hysteresis behavior has been the subject of a recent investigation utilizing a newly constructed wind tunnel facility at Memorial University. The post-stable response of a 1.375-pitch ratio parallel triangular array was first generated under steady flow conditions, with positive velocity increments to just beyond the threshold, then velocity reductions in steps back to stable amplitude levels. It was found that an array with 7 central flexible tubes displayed a fairly broad hysteresis loop, while the same array with only a single flexible tube displayed no hysteresis. The transition from steady stable response levels to steady unstable response levels was then investigated using two types of transient excitation: tube displacement and flow velocity. The effect of increasing tube damping was also investigated.
The Totally Supercritical Steam Cycle
Authors: Potter J. H.
Published: March 2013

Recently a number of new power cycles have been proposed in which heat rejection as well as heat addition has been at supercritical pressure. Although a number of working fluids have been suggested, the present study is restricted to steam. The advantages and limitations of the totally supercritical steam cycle are explored in terms of the conditions under which modern power stations operate.
Approximate Analysis of the Plastic Limit Pressures of Nozzles in Cylindrical Shells
Authors: Cloud R. L. , Rodabaugh E. C.
Published: March 2013

An estimate of the limit pressure for cylindrical nozzles in cylindrical shells is derived from an upper bound analysis based on an assumed velocity distribution. The analysis is restricted to nozzle/shell diameter ratios of 1/2 or less. Comparisons with other theoretical approaches and the results of a single experiment are shown. Design graphs based on the analysis have been prepared to indicate the amount of nozzle or shell thickening required to make the limit pressure of the nozzle-cylinder structure approximately equal to the yield pressure of the imperforated cylinder.
Axial Cascade Technology and Application to Flow Path Designs. Part II—Application of Data to Flow Path Designs
Authors: Balje´ O. E.
Published: March 2013

The cascade considerations presented in Part I are extended to obtain interrelations between cascade parameters and machine similarity parameters, and to assess the effect of compressibility on these interrelations. These data are used to compute the efficiency potential and cavitation sensitivity of single cascaded and multiple cascaded axial machines in the medium to high specific speed regime. The calculated data show fair agreement with the available test information. The effect of only a limited number of design parameters has been investigated. Further studies will be required to cover the performance potential adequately.
Axial Turbine Performance Evaluation. Part B—Optimization With and Without Constraints
Authors: Balje´ O. E. , Binsley R. L.
Published: March 2013

The maximum obtainable efficiency and associated geometry have been calculated based on the use of generalized loss correlations from Part A and are presented for full and partial admission turbines over a wide range of specific speeds. The calculated effects of varying values of Reynolds number, tip clearance, and trailing edge thickness on turbine performance are presented. Because of the anticipated difficulty in fabricating some of the optimum geometries calculated, the effects of using nonoptimum values of geometric parameters on attainable efficiency have also been investigated. The derating factor for machine Reynolds number is shown to be a strong function of specific speed, varying from 0.96 at a specific speed of 100, to 0.6 at a specific speed of 3, when Reynolds number is 105 compared to a reference value of 106. The derating factor for tip clearance is shown to be similar to what would be expected if the clearance area were considered as a leakage area. The use of blade heights, blade numbers, rotor exit angles, and degrees of reaction varying from the optimum by 25 percent produce maximum derating factors of 0.99, 0.98, 0.985, and 0.97, respectively, when compared to full optimum values.
An Axial Flow Reversing Gas Turbine for Marine Propulsion
Authors: Allen R. P. , Butler E. A.
Published: March 2013

The potential advantages of an axial flow reversing marine gas turbine are presented in order to demonstrate the system’s aerodynamic and mechanical feasibility. From this analysis, it has been determined that such a system can be developed for operational use and will be competitive with other applicable thrust reversing mechanisms. The key to success of this system depends upon the establishment of a universally applicable calculation method for determining the rotation losses for backward-turning blades. A theory has been developed and utilized, with the predicted losses in good agreement with the limited test results that have been reported and are available. The aerodynamic and mechanical features developed for the reversing scheme are well within existing technology. Actual construction of a usable system depends primarily upon the increased demand for marine gas turbine propulsion equipment.
CODAG Propulsion Machinery by Stal-Laval for Royal Danish Navy Frigates
Authors: Kumlin Bo R. V.
Published: March 2013

Two gas turbine-powered frigates for the Royal Danish Navy will go on sea trials during 1966. The CODAG propulsion units have good fuel consumption characteristics and light weight. Freewheeling clutches on each prime mover and a controllable pitch propeller have simplified the gear arrangement and the maneuvering procedure. The jet engine-powered gas turbines and the gears are described in some detail in the paper, which ends with a summary of the results from shop tests with the complete propulsion units.
The Telemetering of Information From a Working Internal-Combustion Engine
Authors: Westbrook M. H. , Munro R.
Published: March 2013

This paper describes the problems implicit in obtaining information on movement, temperature, and strain from the reciprocating parts of internal-combustion engines, and considers the various methods of telemetering the information out and the types of transducer which are suitable for use both in conjunction with the telemetering methods to be used and with the environment encountered. The complementary telemetering systems, one using a VHF/FM radio link, which have been developed at the authors’ establishment, are described in detail and their operation in conjunction with transducers for the measurement of movement, temperature, and strain considered. A subminiature inductive transducer specially developed for the noncontact measurement of movements in the frequency range from d-c to 25 kc/s is described in some detail. Results so far obtained from the two systems, particularly in respect of lateral piston movement in the cylinder bore, are presented and the future program of work discussed.
Design and Construction of a Thermal Radiation Probe
Authors: Orning A. A. , Schwartz C. H.
Published: March 2013

A thermal radiation probe was constructed and tested in pulverized-coal-fired furnaces. A rotatable sensing head on the side of a water-cooled probe permitted measurement of radiant flux within a 12.5 deg cone from any desired direction to a point within a furnace. A response curve for a corner-fired furnace showed radiant flux of 130,000 Btu per sq ft, hr, when viewing flame, and 60,000 Btu per sq ft, hr, when sensing wall reflection. Selected drawings of probe construction are given. Additional drawings are available from the U. S. Bureau of Mines.
A Calorimetric Method for Determination of Solid Fraction During Solidification in a Linear Electromagnetic Stirrer
Authors: Kumar P. , Lakshmi H. , Dutta P.
Published: March 2013

In many industrial casting processes, knowledge of the solid fraction evolution during the solidification process is a key factor in determining the process design parameters such as cooling rate and stirring intensity, and in estimating the total solidification time. In the present work, a new method for estimating solid fraction is presented, which is based on calorimetric principles. In this method, the cooling curve data at each point in the melt, along with the thermal boundary conditions, are used to perform energy balance in the mould, from which solid fraction generation during any time interval can be estimated. This method is applied to the case of a rheocasting process, in which Al–Si alloy (A356 alloy) is solidified by stirring in a cylindrical mould placed in the annulus of a linear electromagnetic stirrer. The metal in the mould is simultaneously cooled and stirred to produce a cylindrical billet with nondendritic globular microstructure. Temperature is measured at key locations in the mould to assess the various heat exchange processes prevalent in the mould and to monitor the solidification rate. The results obtained by energy balance method are compared with those by the conventional procedure of calculating solid fraction using the Scheil’s equation.
Computer Simulation of Drying of Food Products With Superheated Steam in a Rotary Kiln
Authors: Sinhal Koustubh , Ghoshdastidar P. S. , Dasgupta Bhaskar
Published: March 2013

The present work reports a computer simulation study of heat transfer in a rotary kiln used for drying and preheating food products such as fruits and vegetables with superheated steam at 1 bar. The heat transfer model includes radiation exchange among the superheated steam, refractory wall and the solid surface, conduction in the refractory wall, and the mass and energy balances of the steam and solids. The gas convection is also considered. Finite-difference techniques are used, and the steady state thermal conditions are assumed. The false transient approach is used to solve the wall conduction equation. The solution is initiated at the inlet of the kiln and proceeds to the exit. The output data consist of distributions of the refractory wall temperature, solid temperature, steam temperature, and the total kiln length. The inlet of the kiln is the outlet of the gas (superheated steam), since the gas flow is countercurrent to the solid. Thus, for a fixed solid and gas temperature at the kiln inlet, the program predicts the inlet temperature of the gas (i.e., at the kiln exit) in order to achieve the specified exit temperature of the gas. In the absence of experimental results for food drying in a rotary kiln, the present model has been satisfactorily validated against numerical results of Sass (1967, “Simulation of the Heat-Transfer Phenomena in a Rotary Kiln,” Ind. Eng. Chem. Process Des. Dev., 6(4), pp. 532–535) and limited measured gas temperature as reported by Sass (1967, “Simulation of the Heat-Transfer Phenomena in a Rotary Kiln,” Ind. Eng. Chem. Process Des. Dev., 6(4), pp. 532–535) for drying of wet iron ore in a rotary kiln. The results are presented for drying of apple and carrot pieces. A detailed parametric study indicates that the influence of controlling parameters such as percent water content (with respect to dry solids), solids flow rate, gas flow rate, kiln inclination angle, and the rotational speed of the kiln on the axial solids and gas temperature profiles and the total predicted kiln length is appreciable. The effects of inlet solid temperature and exit gas temperature on the predicted kiln length for carrot drying are also shown in this paper.
Singularity Conditions
of 3T1R Parallel Manipulators With Identical Limb
Structures
Authors: Amine Semaan , Tale
Masouleh Mehdi , Caro Stéphane , Wenger Philippe , Gosselin Clément
Published: March 2013

This paper deals with the singularity analysis of parallel manipulators with identical limb structures performing Schönflies motions, namely, three independent translations and one rotation about an axis of fixed direction (3T1R). Eleven architectures obtained from a recent type synthesis of such manipulators are analyzed. The constraint analysis shows that these architectures are all overconstrained and share some common properties between the actuation and the constraint wrenches. The singularities of such manipulators are examined through the singularity analysis of the 4-RUU parallel manipulator. A wrench graph representing the constraint wrenches and the actuation forces of the manipulator is introduced to formulate its superbracket. Grassmann–Cayley Algebra is used to obtain geometric singularity conditions. Based on the concept of wrench graph, Grassmann geometry is used to show the rank deficiency of the Jacobian matrix for the singularity conditions. Finally, this paper shows the general aspect of the obtained singularity conditions and their validity for 3T1R parallel manipulators with identical limb structures.
Carbamylation of Serum Albumin as a Risk Factor for Mortality in Patients with Kidney Failure
Authors: Berg Anders H. , Drechsler Christiane , Wenger Julia , Buccafusca Roberto , Hod Tammy , Kalim Sahir , Ramma Wenda , Parikh Samir M. , Steen Hanno , Friedman David J. , Danziger John , Wanner Christoph , Thadhani Ravi , Karumanchi S. Ananth
Published: March 2013

Increased carbamylation of serum albumin is associated with increased mortality in patients with kidney failure.
Genome Sequence of the Alkaliphilic Bacterial Strain
Bacillus ligninesis
L1, a Novel Degrader of Lignin
Authors: Zhu Daochen , Li Pingping , Tanabe Shoko-Hosoi , Sun Jianzhong
Published: March 2013

Bacillus ligninesis
strain L1, isolated from seafloor sediment, was able to grow on medium with lignin as its sole carbon source. Here, we report a 3.8-Mbp high-quality genome sequence for this bacterium. The genes involving ectoine and glycine betaine synthesis, as well as those involved in the degradation of lignin, were identified.
Performance of the Cepheid CT/NG Xpert Rapid PCR Test for Detection of Chlamydia trachomatis and Neisseria gonorrhoeae
Authors: Gaydos Charlotte A. , Van Der Pol Barbara , Jett-Goheen Mary , Barnes Mathilda , Quinn Nicole , Clark Carey , Daniel Grace E. , Dixon Paula B. , Hook Edward W. ,   The CT/NG Study Group
Published: March 2013

Tests for
Chlamydia trachomatis
and
Neisseria gonorrhoeae
, which can provide results rapidly to guide therapeutic decision-making, offer patient care advantages over laboratory-based tests that require several days to provide results. We compared results from the Cepheid GeneXpert CT/NG (Xpert) assay to results from two currently approved nucleic acid amplification assays in 1,722 female and 1,387 male volunteers. Results for chlamydia in females demonstrated sensitivities for endocervical, vaginal, and urine samples of 97.4%, 98.7%, and 97.6%, respectively, and for urine samples from males, a sensitivity of 97.5%, with all specificity estimates being ≥99.4%. Results for gonorrhea in females demonstrated sensitivities for endocervical, vaginal, and urine samples of 100.0%, 100.0%, and 95.6%, respectively, and for urine samples from males, a sensitivity of 98.0%, with all estimates of specificity being ≥99.8%. These results indicate that this short-turnaround-time test can be used to accurately test patients and to possibly do so at the site of care, thus potentially improving chlamydia and gonorrhea control efforts.
Effect of Electroacupuncture on Function and Quality of Life in Parkinson's Disease: A Case Report
Authors: Arankalle Dhananjay Vijay , Nair Pradeep M K
Published: March 2013

A 56-year-old man diagnosed in 2003 as having Hoehn & Yahr stage III Parkinson's disease (PD) came to our clinic in 2012 with slurred speech, right-sided bradykinesia, erectile dysfunction, rigidity, emotional instability and depression. His PD showed progressive signs with postural instability, moderate bilateral signs, and he rated 80% on the Schwab & England Activities of Daily Living Scale. A modified protocol of electroacupuncture was administered for a period of 5 weeks, six times per week, with each session lasting for 30 min. Assessments were based on the Berg Balance Scale (BBS) and Parkinson's Disease Questionnaire-39 (PDQ-39) items, a disease-specific measure of subjective health status. He showed improvement on the BBS, suggesting improved functional status. His quality of life showed improvement particularly on the ‘activities of daily living’, ‘cognition’ and ‘communication’ dimensions of the PDQ-39. Acupuncture treatments in animal experiments have generated valuable mechanistic insights that could be relevant to PD, for example, demonstrating its neuroprotective potential from stimulation of various neuroprotective agents. The literature also suggests acupuncture may play a role in the improvement of motor function and quality of life in PD. Acupuncture is tolerated well by individuals with PD and should be considered as an integrative approach for their symptomatic management.
Non-healing pharyngeal ulcer in a middle-aged Caucasian man
Authors: Nwankwo Nwabundo , Saba Raya , Mirrakhimov Aibek E , Rao Shesh
Published: March 2013

Extranodal natural killer NK/T-cell lymphoma is a rare malignancy. The disease is common in some Asian countries such as China, Japan as well as in South America. We present a case of extranodal NK/T-cell lymphoma which presented as a pharyngeal ulcer in a 35-year-old Caucasian man.
Meningoencephalitis of unknown origin: investigation of prognostic factors and outcome using a standard treatment protocol
Authors: Lowrie M. , Smith P. M. , Garosi L.
Published: March 2013

Meningoencephalitis of unknown origin (MUO) is a common inflammatory CNS disease in dogs, with a variable and unpredictable outcome. MRI and cerebrospinal fluid (CSF) features were prospectively evaluated to establish their utility as prognostic markers for predicting mortality, relapse and long‐term outcome in 39 dogs with MUO. MRI and CSF analysis were performed at initial diagnosis and three months into treatment with prednisolone and cytosine arabinoside. When possible, MRI was repeated every 12 months thereafter. Median survival time was 26 days. All deaths occurred within 52 days of diagnosis (22/39; 56 per cent). One‐third (13/39) died within 72 hours of diagnosis. Outcome was good or excellent in 12/17 surviving dogs. Loss of the cerebral sulci and foramen magnum herniation on MRI were associated with increased risk of mortality. An abnormal CSF analysis at the three‐month re‐examination was associated with increased risk of relapse (P=0.04). The combination of MRI and CSF analysis provided a greater sensitivity for predicting relapse than one modality alone. Discontinuing treatment before MRI lesions resolved always resulted in relapse. The presence of certain MRI characteristics may indicate an increased risk of mortality. Dogs alive three months following diagnosis have a very low risk of death due to MUO.
Effects of different levels of physical inactivity on plasma visfatin in healthy normal-weight men
Authors: Rudwill Floriane , Blanc Stéphane , Gauquelin-Koch Guillemette , Choukèr Alexander , Heer Martina , Simon Chantal , Bergouignan Audrey
Published: March 2013

We tested whether physical inactivity (PI) is an independent predictor of plasma visfatin, a newly discovered adipokine likely involved in the relationship between obesity-associated low-grade inflammation and insulin resistance. PI was induced in healthy men (Body Mass Index = 23.4 ± 0.6 kg·m−2) by 10 days of confinement (n = 8), 1 month of detraining (n = 10), and 3 months of bed rest with (n = 7) and without exercise (n = 8). Visfatin was negatively associated with activity energy expenditure (p = 0.03). No relationship was observed with insulin sensitivity. This suggested that PI itself increases visfatin concentrations.
Atmospheric oxidation mechanism of polyfluorinated sulfonamides — A quantum chemical and kinetic study
Authors: Sun Xiaoyan , Ding Lei , Zhang Qingzhu , Wang Wenxing
Published: March 2013

Polyfluorinated sulfonamides (FSAs, F(CF2)nSO2NR1R2) are present in the atmosphere and may serve as the source of perfluorocarboxylates (PFCAs, CF3(CF2)nCOO–) in remote locations through long-range atmospheric transport and oxidation. Density functional theory (DFT) molecular orbital theory calculations were carried out to investigate OH radical-initiated atmospheric oxidation of a series of sulfonamides, F(CF2)nSO2NR1R2 (n = 4, 6, 8). Geometry optimizations of the reactants as well as the intermediates, transition states, and products were performed at the MPWB1K level with the 6-31G+(d,p) basis set. Single-point energy calculations were carried out at the MPWB1K/6-311+G(3df,2p) level of theory. The OH radical-initiated reaction mechanism is given and confirms that the OH addition to the sulfone double bond producing perfluoroalkanesulfonic acid directly cannot occur in the general atmosphere. Canonical variational transition-state (CVT) theory with small curvature tunneling (SCT) contribution was used to predict the rate constants. The overall rate constants were determined, k(T) (N-EtFBSA + OH) = (3.21 × 10−12) exp(–584.19/T), k(T) (N-EtFHxSA + OH) = (3.21 × 10−12) exp(–543.24/T), and k(T) (N-EtFOSA + OH) = (2.17 × 10−12) exp(–504.96/T) cm3 molecule−1 s−1, over the possible atmospheric temperature range of 180–370 K, indicating that the length of the F(CF2)n group has no large effect on the reactivity of FSAs. Results show that the atmospheric lifetime of FSAs determined by OH radicals will be 20–40 days, which agrees well with the experimental values (20–50 days), 20 thus they may contribute to the burden of perfluorinated pollution in remote regions.