bluuebunny/crossref_metadata_2025 huggingface dataset:
Vibration and Deflection of a Silicon-Wafer Slicer Cutting the Crystal Ingot
Authors: Chonan S. , Jiang Z. W. , Yuki Y.
Published: June 2008

Vibration and deflection of a silicon-wafer slicer cutting the crystal ingot is studied analytically. The blade is clamped and then tensioned in the radial direction at the outer boundary. The inner periphery is under the action of distributed in-plane and lateral slicing loads from the workpiece. The stresses from tensioning, spinning, and loading from the workpiece are taken into account in the in-plane stress evaluation of the blade. The solution is obtained by introducing the multi-modal expansion and applying the Galerkin method to the governing equation of the blade. Numerical results are presented for an actual SUS 301 blade cutting a 15.24 cm (6 in.) diameter silicon ingot. Results obtained show that the initial tensioning has a significant effect on the natural frequencies of the blade, while the lateral deflection of the blade is much affected by the lateral reaction force from the ingot.
Two-Channel Laser Vibrometer Techniques for Vibrational Intensity Measurements: Part 2—Longitudinal Intensity
Authors: McDevitt T. E. , Koopmann G. H. , Burroughs C. B.
Published: June 2008

This paper extends the application of a two-channel vibrometer technique from the measurement of flexural energy flow (detailed in Part 1) to the measurement of longitudinal energy flow. The two-channel longitudinal energy flow equations and two one-dimensional validation methods are presented along with a discussion of how laser vibrometry functions for the measurement of in-plane vibratory motion. Adaptations of the energy flow equations to laser vibrometry are also presented. Experimental results are illustrated which contain the influence of a bending-induced longitudinal component of motion. Through a mathematical model, the measurement of the longitudinal energy flow is shown to be accurate if the influence of bending-induced longitudinal motion is removed.
Navier-Stokes Computations of Cavity Aeroacoustics with Suppression Devices
Authors: Baysal Oktay , Yen Guan-Wei , Fouladi Kamran
Published: June 2008

Effectiveness of two devices to suppress the cavity acoustics was computationally investigated. Two dimensional, computational simulations were performed for the transonic, turbulent flows past a cavity, which was first equipped with a rear face ramp and then with a spoiler. The Reynolds-averaged, unsteady, compressible, full Navier-Stokes equations were solved time accurately by a second-order accurate, implicit, upwind, finite-volume method. The effect of turbulence was included through the Baldwin-Lomax model with modifications for the multiple-wall effects and for the highly vortical flow with a shear layer. The results included instantaneous and time-averaged flow properties, and time-series analyses of the pressure inside the cavity, which compared favorably with the available experimental data. These results were also contrasted with the computed aeroacoustics of the same cavity (length-to-depth ratio of 4.5), but without a device, to demonstrate the suppression effectiveness.
A Method for the Calculation of Natural Frequencies of Orthotropic Axisymmetrically Loaded Shells of Revolution
Authors: Kayran A. , Vinson J. R. , Ardic E. Selcuk
Published: June 2008

A methodology is presented for the calculation of the natural frequencies of orthotropic axisymmetrically loaded shells of revolution including the effect of transverse shear deformation. The fundamental system of equations governing the free vibration of the stress-free shells of revolution are modified such that the initial stresses due to the axisymmetric loading are incorporated into the analysis. The linear equations on the vibration about the deformed state are solved by using the transfer matrix method which makes use of the multisegment numerical integration technique. This method is commonly known as frequency trial method. The solution for the initial stresses due to axisymmetric loading is omitted; since the application of the transfer matrix method, making use of multisegment numerical integration technique for both linear and nonlinear equations are available in the literature. The method is verified by applying it to the solution of the natural frequencies of spinning disks, for which exact solutions exist in the literature, and a deep paraboloid for which approximate solutions exist. The governing equations for a shell of revolution are used to approximate circular disks by decreasing the curvature of the shell of revolution to very low values, and good agreement is seen between the results of the present method and the exact solution for spinning disks and the approximate solution for a deep paraboloid.
Collocated Sensor/Actuator Positioning and Feedback Design in the Control of Flexible Structure System
Authors: Lee An-Chen , Chen Song-Tsuen
Published: June 2008

This paper presents a new control design method for the control of flexible systems that not only guarantees closed-loop asymptotic stability but also effectively suppresses vibration. This method allows integrated determination of actuator/sensor locations and feedback gain via minimization of an energy criterion, which is chosen as the integrated total energy stored in the system. The energy criterion is determined via an efficient solution of the Lyapunov equation and minimized with a quasi-Newton or recursive quadratic programming algorithm. The prerequisite for this optimal design method is that the controlled system be asymptotically stable. This study shows that when the controller structure is a collocated direct velocity feedback design with positive definite feedback gain, the number and placement of actuators/sensors are the only factors needed to determine necessary and sufficient conditions for ensuring closed-loop asymptotic stability. The application of this method to a simple flexible structure confirms the direct relationship between our optimization criterion and effectiveness in vibration suppression.
Optimization of Magnetic Pole Geometry for Field Harmonic Control in Electric Motors
Authors: Rahman B. S. , Lieu D. K.
Published: June 2008

A principal source of vibration in permanent magnet motors and generators is the induced stress from the rotating permanent magnets. The harmonic content of this forcing function may excite resonant modes of vibration in the motor or surrounding structure. Thus attenuation of specific harmonics is of considerable interest. This paper describes a method for optimal shaping of the permanent magnets to eliminate one or more of these harmonics. The analytical model for an optimized 4-pole motor consisted of segmented PMs and a solid ring stator. The permanent magnets were modeled as a number of thin radially cut annular layers with specific sector angles. Changing the shape of the PMs resulted in a different flux density field and thus a different frequency spectrum of the forcing function. Attenuation of specified higher harmonics could be achieved at the expense of increasing other harmonics. For a 4-pole motor, the optimization algorithm was fairly successful at eliminating any one of the 8th, 12th or 16th harmonics. The algorithm used was developed to solve combinatorial optimization problems, and drew heavily upon principles from statistical mechanics. The final pole geometry is dependent upon the choice of the cost function used in the optimization algorithm.
Effect of Rotation on Vibration of Moderately Thick Circular Cylindrical Shells
Authors: Sivadas K. R. , Ganesan N.
Published: June 2008

Circular cylindrical shells rotating about their axis of revolution are analyzed for natural frequencies and damping factor using moderately thick shell theory with shear deformation and rotatory inertia. A subparametric axisymmetric finite element with 5 nodes to represent the function variations, and 2 nodes to represent coordinate variations is used for the solution. Full Fourier expansion is used in the circumferential direction to overcome the effect of material anisotropy and Coriolis component. The effect of rotation on frequencies is studied by incorporating the Coriolis acceleration, rotational energy, prestressing due to centrifugal force, and damping due to material.
A Technique to Measure the Breathing Wave Speed in a Towed Array
Authors: Hull Andrew J.
Published: June 2008

A method is developed for measuring the breathing wave speed in a towed array. The front of the array is longitudinally vibrated, producing aft-traveling wave energy that is detected by measuring the transfer function of a hydrophone channel and a forward bulkhead-mounted accelerometer. The transfer function is composed of two distinct wave types: an extensional wave and a breathing wave. The breathing wavelengths are much shorter than the extensional wavelengths; therefore, the local minimum associated with the first breathing wave null across the hydrophone channel can be identified. Because the frequency at which this null occurs and the length of the hydrophone channel are known, the breathing wave speed can be calculated.
Dynamic Properties of the Rigid Body and Supports from Vibration Measurements
Authors: Pandit S. M. , Yao Y.-X. , Hu Z.-Q.
Published: June 2008

A novel method is presented to determine the dynamic characteristics of a multi-DOF rigid body structure from vibration measurements and coordinates of the transducers. These characteristics include the center of gravity, moment of inertia, and mass; stiffness, center of stiffness and moment of stiffness; damping, center of damping and moment of damping; and corresponding principal values and axes. The method is capable of handling complicated structures with various DOFs, from 2 up to maximum 6. The mass modified matrices M−1K and M−1C (or mass M, stiffness K, and damping C matrices) are first obtained based on measured vibration data and estimated rigid-body modes by Data Dependent Systems (DDS) methodology, which is accurate even for highly damped structures. Relationships between the physical characteristics and the mass modified matrices have been derived to solve the dynamic properties. The properties of up to 5 individual spring and dashpot supports can be determined by solving linear simultaneous equations. New concepts about the center of stiffness, moment of stiffness, center of damping, and moment of damping and the estimation method are presented. An example, using a simple structure, demonstrated the capability of the proposed method.
Dynamic Analysis and Design of a Machine Tool Spindle-Bearing System
Authors: Wang W. R. , Chang C. N.
Published: June 2008

The paper simulates a spindle-bearing system with a finite-element model; then compares it to the experimental results. Radial and tilting springs and dashpots are considered in angular contact spindle ball bearings. This FEM model shows that additional tilting characteristics make significant effect on higher-order vibration modes. The design parameters used in this study are bearing preloads, bearing spacings, mass inserts on spindle and damping. Computations and experimental results show that improvements can be made by adjusting the forementioned parameters.
A Modified Transfer Matrix Method for Asymmetric Rotor-Bearing Systems
Authors: Kang Yuan , Lee An-Chen , Shih Yuan-Pin
Published: June 2008

A modified transfer matrix method (MTMM) is developed to analyze rotor-bearing systems with an asymmetric shaft and asymmetric disks. The rotating shaft is modeled by a Rayleigh-Euler beam considering the effects of the rotary inertia and gyroscopic moments. Specifically, a transfer matrix of the asymmetric shaft segments is derived in a continuous-system sense to give accurate solutions. The harmonic balance method is incorporated in the transfer matrix equations, so that steady-state responses of synchronous and superharmonic whirls can be determined. A numerical example is presented to demonstrate the effectiveness of this approach.
An Energy-Based Formulation for Computing Nonlinear Normal Modes in Undamped Continuous Systems
Authors: King M. E. , Vakakis A. F.
Published: June 2008

The nonlinear normal modes of a class of one-dimensional, conservative, continuous systems are examined. These are free, periodic motions during which all particles of the system reach their extremum amplitudes at the same instant of time. During a nonlinear normal mode, the motion of an arbitrary particle of the system is expressed in terms of the motion of a certain reference point by means of a modal function. Conservation of energy is imposed to construct a partial differential equation satisfied by the modal function, which is asymptotically solved using a perturbation methodology. The stability of the detected nonlinear modes is then investigated by expanding the corresponding variational equations in bases of orthogonal polynomials and analyzing the resulting set of linear differential equations with periodic coefficients by Floquet analysis. Applications of the general theory are given by computing the nonlinear normal modes of a simply-supported beam lying on a nonlinear elastic foundation, and of a cantilever beam possessing geometric nonlinearities.
A Consistent Higher-Order Theory of Laminated Plates with Nonlinear Impact Modal Analysis
Authors: Chao C. C. , Tung T. P. , Sheu C. C. , Tseng J. H.
Published: June 2008

A consistent higher-order theory is developed for cross-ply laminated thick plates under transverse normal impact via an energy variational approach, in which the 3-D surface/edge boundary conditions and interlaminar displacement/stress continuities are satisfied, in an attempt to find the dynamic deformation and all six stress components throughout the plate during the impact process. The dynamic displacement field is expressed in a mixed form of in-plane double Fourier series and cubic polynomials through thickness as 12 variables for each layer. A system of modified Lagrange’s equations is derived with all surface and interface constraints included. The nonlinear impact modal analysis is performed using the Hertz contact law in a patch loading simulation and Green’s function for small time-steps linearization. The 3-D displacements are found with thickness shrinking and stresses generally unsymmetric with respect to the mid-surface. Tensile cracks are predicted at the unimpacted side.
Accelerating Load on a Rotating Rayleigh Beam
Authors: Argento A. , Morano H. L. , Scott R. A.
Published: June 2008

The response of a rotating Rayleigh beam subjected to an axially accelerated distributed surface line load is studied. Clamped-clamped, clamped-pinned, and clamped-free support conditions and four types of load velocity profiles are treated. Galerkin’s method is used to suppress spatial dependence in the equations of motion; the resulting time dependent equations are numerically integrated. Results are presented for the beam displacement in the direction of the load and the gyroscopically induced transverse component. The effects of load speed, beam rotational speed, and geometry are studied; the potential for control of the beam vibrations by adjustment of the load velocity profile is discussed.
Natural Frequencies Formula for Simply Supported Mindlin Plates
Authors: Wang C. M.
Published: June 2008

This paper presents an explicit formula for the vibration frequencies of simply supported Mindlin plates in terms of the corresponding thin (Kirchhoff) plate frequencies. The formula has been obtained from an exact vibration analysis of simply supported rectangular Mindlin plates. When the formula was applied to other simply supported plate shapes such as skew plates, circular and annular sectorial plates, it was found to give almost exact solutions. It appears that the formula can be used to predict the frequencies accurately for any simply supported plate shape and thus should be valuable to designers as Mindlin vibration solutions are scarce.
Molecular Characterization of
Giardia
Isolates from Calves and Humans in a Region in Which Dairy Farming Has Recently Intensified
Authors: Winkworth Cynthia L. , Learmonth James J. , Matthaei Christoph D. , Townsend Colin R.
Published: June 2008

Giardiasis is a notifiable disease of high prevalence in New Zealand, but there is limited knowledge about the sources of
Giardia duodenalis
genotypes that can potentially cause human infections. Dairy calves are one environmental source of
Giardia
isolates, but it is unknown whether they harbor genotypes that are potentially capable of causing infections in humans. To address these questions, 40
Giardia
isolates from calves and 30 from humans, living in the same region and collected over a similar period, were genotyped using the β-giardin gene. The
G. duodenalis
genetic assemblages A and B were identified from both calves and humans, and genotype comparisons revealed a substantial overlap of identical genotypes from the two hosts for both assemblages. Significantly, no assemblage E (the genotype commonly found in cattle elsewhere in the world) has been detected in New Zealand livestock to date. Given recent and rapid land use conversions to dairy farming in many South Island regions of New Zealand, an increasingly large concentration of domestic cattle harboring genotypes potentially capable of causing infections in humans is particularly concerning.
Evaluation of PCR Primer Selectivity and Phylogenetic Specificity by Using Amplification of 16S rRNA Genes from Betaproteobacterial Ammonia-Oxidizing Bacteria in Environmental Samples
Authors: Junier Pilar , Kim Ok-Sun , Hadas Ora , Imhoff Johannes F. , Witzel Karl-Paul
Published: June 2008

The effect of primer specificity for studying the diversity of ammonia-oxidizing betaproteobacteria (βAOB) was evaluated. βAOB represent a group of phylogenetically related organisms for which the 16S rRNA gene approach is especially suitable. We used experimental comparisons of primer performance with water samples, together with an in silico analysis of published sequences and a literature review of clone libraries made with four specific PCR primers for the βAOB 16S rRNA gene. With four aquatic samples, the primers NitA/NitB produced the highest frequency of ammonia-oxidizing-bacterium-like sequences compared to clone libraries with products amplified with the primer combinations βAMOf/βAMOr, βAMOf/Nso1255g, and NitA/Nso1225g. Both the experimental examination of ammonia-oxidizing-bacterium-specific 16S rRNA gene primers and the literature search showed that neither specificity nor sensitivity of primer combinations can be evaluated reliably only by sequence comparison. Apparently, the combination of sequence comparison and experimental data is the best approach to detect possible biases of PCR primers. Although this study focused on βAOB, the results presented here more generally exemplify the importance of primer selection and potential primer bias when analyzing microbial communities in environmental samples.
Comparative Study of Sugar Fermentation and Protein Expression Patterns of Two
Lactobacillus plantarum
Strains Grown in Three Different Media
Authors: Plumed-Ferrer Carme , Koistinen Kaisa M. , Tolonen Tiina L. , Lehesranta Satu J. , Kärenlampi Sirpa O. , Mäkimattila Elina , Joutsjoki Vesa , Virtanen Vesa , von Wright Atte
Published: June 2008

A comparative study of two strains of
Lactobacillus plantarum
(REB1 and MLBPL1) grown in commercial medium (MRS broth), cucumber juice, and liquid pig feed was performed to explore changes to the metabolic pathways of these bacteria, using a proteomics approach (two-dimensional electrophoresis and liquid chromatography-tandem mass spectrometry) combined with analyses of fermentable sugars and fermentation end products. The protein expression showed that even with an excess of glucose in all media, both strains could metabolize different carbohydrates simultaneously and that hexoses could also be used via a phosphoketolase pathway with preferential expression in liquid feed. Sugar analyses showed that the fermentation of sugars was homolactic for all media, with some heterolactic activity in liquid feed, as shown by the production of acetate. Cucumber juice (the medium with the highest glucose content) showed the lowest hexose consumption (10%), followed by liquid feed (33%) and MRS broth (50%). However, bacterial growth was significantly higher in cucumber juice and liquid feed than in MRS broth. This discrepancy was due to the growth benefit obtained from the utilization of the malate present in cucumber juice and liquid feed. Despite different growth conditions, the synthesis of essential cellular components and the stress response of the bacteria were unaffected. This study has improved our understanding of the mechanisms involved in the growth performance of an appropriate lactic acid bacterium strain to be used for food and feed fermentation, information that is of crucial importance to obtain a high-quality fermented product.
Neisseria gonorrhoeae
Uses Two Lytic Transglycosylases To Produce Cytotoxic Peptidoglycan Monomers
Authors: Cloud-Hansen Karen A. , Hackett Kathleen T. , Garcia Daniel L. , Dillard Joseph P.
Published: June 2008

Peptidoglycan fragments released by
Neisseria gonorrhoeae
contribute to the inflammation and ciliated cell death associated with gonorrhea and pelvic inflammatory disease. However, little is known about the production and release of these fragments during bacterial growth. Previous studies demonstrated that one lytic transglycosylase, LtgA, was responsible for the production of approximately half of the released peptidoglycan monomers. Systematic mutational analysis of other putative lytic transglycosylase genes identified lytic transglycosylase D (LtgD) as responsible for release of peptidoglycan monomers from gonococci. An
ltgA ltgD
double mutant was found not to release peptidoglycan monomers and instead released large, soluble peptidoglycan fragments. In pulse-chase experiments, recycled peptidoglycan was not found in cytoplasmic extracts from the
ltgA ltgD
mutant as it was for the wild-type strain, indicating that generation of anhydro peptidoglycan monomers by lytic transglycosylases facilitates peptidoglycan recycling. The
ltgA ltgD
double mutant showed no growth abnormalities or cell separation defects, suggesting that these enzymes are involved in pathogenesis but not necessary for normal growth.
Idiopathic elevated episcleral venous pressure and open-angle glaucoma
Authors: Rhee D J , Gupta M , Moncavage M B , Moster M L , Moster M R
Published: June 2008

Background/aims:

To report a case series of Idiopathic Elevated Episcleral Venous Pressure (IEEVP).

Methods:

Retrospective chart review of all cases of IEEVP seen over a 5-year period by three physicians.

Results:

Six cases (five men and one woman) are added to the known 19 documented cases in the English literature, only three of which were reported in the last 10 years. By history, the onset of conjunctival injection of all patients was in early adulthood or late teens. None had an identifiable lesion by modern imaging techniques. All cases had bilateral but asymmetric involvement. Four of the six required glaucoma surgery by the 5th to 7th decade of life. The three eyes that had glaucoma filtration surgery had good outcomes. Choroidal effusions occurred in the postoperative period of one eye which was not hypotonous.

Conclusion:

IEEVP is a rare cause of glaucoma which is diagnosed by the clinical criteria of dilated episcleral vessels without an identifiable cause. If glaucoma filtration surgery is required, there are generally good results. However, clinicians must be cautious of choroidal effusions occurring at non-hypotonous intraocular pressures.
AN EOQ MODEL WITH CONTROLLABLE SELLING RATE
Authors: CHANG HORNG-JINH , CHEN PO-YU
Published: June 2008

According to the marketing principle, a decision maker may control demand rate through selling price and the unit facility cost of promoting transaction. In fact, the upper bound of willing-to-pay price and the transaction cost probably depend upon the subjective judgment of individual consumer in purchasing merchandise. This study therefore attempts to construct a bivariate distribution function to simultaneously incorporate the willing-to-pay price and the transaction cost into the classical economic order quantity (EOQ) model. Through the manipulation of the constructed bivariate distribution function, the demand function faced by the supplier can be expressed as a concrete form. The proposed mathematical model mainly concerns how to determine the initial inventory level for each business cycle, so that the profit per unit time is maximized by means of the selling price and the unit-transaction cost to control the selling rate. Furthermore, the sensitivity analysis of optimal solution is performed and the implication of this extended inventory model is also discussed.
ENTANGLEMENT ENTROPY OF THE SIX-DIMENSIONAL HOROWITZ–STROMINGER BLACK HOLE
Authors: LI HUAI-FAN , ZHANG SHENG-LI , WU YUE-QIN , REN ZHAO
Published: June 2008

By using the entanglement entropy method, the statistical entropy of the Bose and Fermi fields in a thin film is calculated and the Bekenstein–Hawking entropy of six-dimensional Horowitz–Strominger black hole is obtained. Here, the Bose and Fermi fields are entangled with the quantum states in six-dimensional Horowitz–Strominger black hole and the fields are outside of the horizon. The divergence of brick-wall model is avoided without any cutoff by the new equation of state density obtained with the generalized uncertainty principle. The calculation implies that the high density quantum states near the event horizon are strongly correlated with the quantum states in black hole. The black hole entropy is a quantum effect. It is an intrinsic characteristic of space–time. The ultraviolet cutoff in the brick-wall model is unreasonable. The generalized uncertainty principle should be considered in the high energy quantum field near the event horizon. Using the quantum statistical method, we directly calculate the partition function of the Bose and Fermi fields under the background of the six-dimensional black hole. The difficulty in solving the wave equations of various particles is overcome.
SEMICLASSICAL CORRECTIONS TO THE CARDY–VERLINDE FORMULA OF KERR BLACK HOLES
Authors: SETARE M. R.
Published: June 2008

In this paper, we compute the corrections to the Cardy–Verlinde formula of four-dimensional Kerr black hole. These corrections are considered within the context of KKW analysis and arise as a result of the self-gravitational effect. Then we show that one can take into account the semiclassical corrections of the Cardy–Verlinde entropy formula by only redefining the Virasoro operator L0 and the central charge c.
A U(3)C × U(3)L × U(3)R GAUGE SYMMETRY FROM INTERSECTING D-BRANES
Authors: LEONTARIS G. K.
Published: June 2008

A three-family nonsupersymmetric model with U(3)3 gauge symmetry is analyzed in the context of intersecting D-branes. This is equivalent to the "trinification" model extended by three U(1) factors which survive as global symmetries in the low energy effective model. The Standard Model fermions are accommodated in the three possible bifundamental multiplets represented by strings with end points attached on different brane-stacks of this particular setup. Further, a natural quark–lepton hierarchy is realized due to the existence of the additional Abelian symmetries.
NONLINEAR PROBLEMS IN INFINITE INTERACTING PARTICLE SYSTEMS
Authors: OLKIEWICZ ROBERT , XU LIHU , ZEGARLIŃSKI BOGUSŁAW
Published: June 2008

We introduce and study a class of nonlinear jump type Markov semigroups for systems with infinite dimensional configuration space.
CONDITIONAL ENTRANCE LAWS FOR SUPERPROCESSES WITH DEPENDENT SPATIAL MOTION
Authors: LI ZENGHU , WANG HAO , XIONG JIE
Published: June 2008

We identify a class of conditional entrance laws for superprocesses with dependent spatial motion (SDSM). Those entrance laws are used to characterize some conditional excursion laws. As an application of the results, we give a sample path decomposition of the SDSM and that of a related immigration superprocess. The main tool used here is the conditional log-Laplace functional technique that handles the difficulty of the loss of the multiplicative property due to the interactions in the spatial motions.
QUANTITATIVE EVALUATION OF RETINAL TUMOR VOLUME IN MOUSE MODEL OF RETINOBLASTOMA BY USING ULTRA HIGH-RESOLUTION OPTICAL COHERENCE TOMOGRAPHY
Authors: RUGGERI MARCO , WEHBE HASSAN , TSECHPENAKIS GAVRIIL , JIAO SHULIANG , JOCKOVICH MARIA ELENA , CEBULLA COLLEEN , HERNANDEZ ELEUT , MURRAY TIMOTHY G. , PULIAFITO CARMEN A.
Published: June 2008

An ultra high resolution spectral-domain optical coherence tomography (SD-OCT) together with an advanced animal restraint and positioning system was built for noninvasive non-contact in vivo three-dimensional imaging of rodent models of ocular diseases. The animal positioning system allowed the operator to rapidly locate and switch the areas of interest on the retina. This function together with the capability of precise spatial registration provided by the generated OCT fundus image allows the system to locate and compare the same lesion (retinal tumor in the current study) at different time point throughout the entire course of the disease progression. An algorithm for fully automatic segmentation of the tumor boundaries and calculation of tumor volume was developed. The system and algorithm were successfully applied to monitoring retinal tumor growth quantitatively over time in the LHBETATAG mouse model of retinoblastoma.
LABEL-FREE DETECTION OF PROTEIN MICROARRAY WITH HIGH THROUGHPUT SURFACE PLASMON RESONANCE IMAGING (SPRI)
Authors: XU SHUKUAN , HUANG GUOLIANG , DENG CHENG , ZHU JIANG , HAN CHAO , YANG XIAOYONG
Published: June 2008

A surface plasmon resonance imaging (SPRI) system was developed for the discrimination of proteins on a gold surface. As a label-free and high-throughput technique, SPRI enables simultaneously monitoring of the biomolecular interactions at low concentrations. We used SPRI as a label-free and parallel method to detect different proteins based on protein microarray. Bovine Serum Albumin (BSA), Casein and Immunoglobulin G (IgG) were immobilized onto the Au surface of a gold-coated glass chip as spots forming a 6 × 6 matrix. These proteins can be discriminated directly by changing the incident angle of light. Excellent reproducibility for label-free detection of protein molecules was achieved. This SPRI platform represents a simple and robust method for performing high-sensitivity detection of protein microarray.
HISTORY AND PRESENT STATE OF TRANSLATIONAL ELECTRO-OPTICAL APPLICATIONS TO MEDICINE
Authors: CHANCE BRITTON , NIOKA SHOKO
Published: June 2008

This paper reviews the history of the optoelectric devices applied to biomedical sciences in 20th century. It describes history of Vacuum tubes and Spectroscopies with the author's personal experiences, especially doublebeam spectroscopy. Further, the present developments of Near Infra Red (NIR) devices are described in translational biomedical applications. It includes particulary micro optoelectronics developments and present status of NIR breast cancer detection. Lastly, intrinsic molecular biomarkers are discussed especially NIR measurements of angiogenensis, hypermetabolism and heat production for cancer detection.
Nonstandard Higgs Boson Decays
Authors: Chang Spencer , Dermíšek Radovan , Gunion John F. , Weiner Neal
Published: June 2008

This review summarizes the motivations for and the phenomenological consequences of nonstandard Higgs boson decays, with an emphasis on final states containing a pair of non–standard model particles that subsequently decay to standard model particles. Typically these non–standard model particles form part of a “hidden” sector, for example a pair of neutral Higgs bosons or a pair of unstable neutralinos. We emphasize that such decays allow for a Higgs substantially below the standard model Higgs Large Electron-Positron Collider limit of 114 GeV. A Higgs with standard model WW, ZZ, and top couplings and a mass near 100 GeV eliminates the fine-tuning problems of many beyond the standard model theories, in particular supersymmetric models, and leads to excellent consistency with precision electroweak data.
Thyroid-stimulating hormone receptor in brown adipose tissue is involved in the regulation of thermogenesis
Authors: Endo Toyoshi , Kobayashi Tetsuro
Published: June 2008

C.RF- Tshrhyt/hytmice have a mutated thyroid-stimulating hormone receptor (TSHR), and, without thyroid hormone supplementation, these mice develop severe hypothyroidism. When hypothyroid Tshrhyt/hytmice were exposed to cold (4°C), rectal temperature rapidly dropped to 23.9 ± 0.40°C at 90 min, whereas the wild-type mice temperatures were 37.0 ± 0.15°C. When we carried out functional rat TSHR gene transfer in the brown adipose tissues by plasmid injection combined with electroporation, there was no effect on the serum levels of thyroxine, although rectal temperature of the mice transfected with pcDNA3.1/Zeo-rat TSHR 90 min after cold exposure remained at 34.6 ± 0.34°C, which was significantly higher than that of Tshrhyt/hytmice. Transfection of TSHR cDNA increased mRNA and protein levels of uncoupling protein-1 (UCP-1) in brown adipose tissues, and the weight ratio of brown adipose tissue to overall body weight also increased. Exogenous thyroid hormone supplementation to Tshrhyt/hytmice restored rectal temperature 90 min after exposure to cold (36.8 ± 0.10°C). These results indicate that not only thyroid hormone but also thyroid-stimulating hormone (TSH)/TSHR are involved in the expression mechanism of UCP-1 in mouse brown adipose tissue. TSH stimulates thermogenesis and functions to protect a further decrease in body temperature in the hypothyroid state.
N-oleoyldopamine, a novel endogenous capsaicin-like lipid, protects the heart against ischemia-reperfusion injury via activation of TRPV1
Authors: Zhong Beihua , Wang Donna H.
Published: June 2008

N-oleoyldopamine (OLDA), a bioactive lipid originally found in the mammalian brain, is an endovanilloid that selectively activates the transient receptor potential vanilloid type 1 (TRPV1) channel. This study tests the hypothesis that OLDA protects the heart against ischemia and reperfusion (I/R) injury via activation of the TRPV1 in wild-type (WT) but not in gene-targeted TRPV1-null mutant (TRPV1−/−) mice. Hearts of WT or TRPV1−/− mice were Langendorffly perfused with OLDA (2 × 10−9 M) in the presence or absence of CGRP8–37 (1 × 10−6 M), a selective calcitonin gene-related peptide (CGRP) receptor antagonist; RP-67580 (1 × 10−6 M), a selective neurokinin-1 receptor antagonist; chelerythrine (5 × 10−6 M), a selective protein kinase C (PKC) antagonist; or tetrabutylammonium (TBA, 5 × 10−4 M), a nonselective K+ channel antagonist, followed by 35 min of global ischemia and 40 min of reperfusion (I/R). Left ventricular end-diastolic pressure (LVEDP), left ventricular developed pressure (LVDP), coronary flow (CF), and left ventricular peak positive dP/d t (+dP/d t) were evaluated after I/R. OLDA improved recovery of cardiac function after I/R in WT but not TRPV1−/− hearts by increasing LVDP, CF, and +dP/d t and by decreasing LVEDP. CGRP8–37, RP-67580, chelerythrine, or TBA abolished the protective effect of OLDA in WT hearts. Radioimmunoassay showed that the release of substance P (SP) and CGRP after OLDA treatment was higher in WT than in TRPV1−/− hearts, which was blocked by chelerythrine or TBA. Thus OLDA exerts a cardiac protective effect during I/R injury in WT hearts via CGRP and SP release, which is abolished by PKC or K+ channel antagonists. The protective effect of OLDA is void in TRPV1−/− hearts, supporting the notion that TRPV1 mediates OLDA-induced protection against cardiac I/R injury.
Cardiac dysfunction in aging conscious rats: altered cardiac cytoskeletal proteins as a potential mechanism
Authors: Lieber Samuel C. , Qiu Hongyu , Chen Li , Shen You-Tang , Hong Chull , Hunter William C. , Aubry Nadine , Vatner Stephen F. , Vatner Dorothy E.
Published: June 2008

The objective of this study was to test the hypothesis that the mechanism mediating left ventricular (LV) dysfunction in the aging rat heart involves, in part, changes in cardiac cytoskeletal components. Our results show that there were no significant differences in heart rate, LV pressure, or LV diameter between conscious, instrumented young [5.9 ± 0.3 mo ( n = 9)] and old rats [30.6 ± 0.1 mo ( n = 10)]. However, the first derivative of LV pressure (LV dP/d t) was reduced (8,309 ± 790 vs. 11,106 ± 555 mmHg/s, P < 0.05) and isovolumic relaxation time (τ) was increased (8.7 ± 0.7 vs. 6.3 ± 0.6 ms, P < 0.05) in old vs. young rats, respectively. The differences in baseline LV function in young and old rats, which were modest, were accentuated after β-adrenergic receptor stimulation with dobutamine (20 μg/kg), which increased LV dP/d t by 170 ± 9% in young rats, significantly more ( P < 0.05) than observed in old rats (115 ± 5%). Volume loading in anesthetized rats demonstrated significantly impaired LV compliance in old rats, as measured by the LV end-diastolic pressure and dimension relationship. In old rat hearts, there was a significant ( P < 0.05) increase in the percentage of LV collagen (2.4 ± 0.2 vs. 1.3 ± 0.2%), α-tubulin (92%), and β-tubulin (2.3-fold), whereas intact desmin decreased by 51%. Thus the cardiomyopathy of aging in old, conscious rats may be due not only to increases in collagen but also to alterations in cytoskeletal proteins.
Mechanisms of lead-induced hypertension and cardiovascular disease
Authors: Vaziri Nosratola D.
Published: June 2008

Lead is a ubiquitous environmental toxin that is capable of causing numerous acute and chronic illnesses. Population studies have demonstrated a link between lead exposure and subsequent development of hypertension (HTN) and cardiovascular disease. In vivo and in vitro studies have shown that chronic lead exposure causes HTN and cardiovascular disease by promoting oxidative stress, limiting nitric oxide availability, impairing nitric oxide signaling, augmenting adrenergic activity, increasing endothelin production, altering the renin-angiotensin system, raising vasoconstrictor prostaglandins, lowering vasodilator prostaglandins, promoting inflammation, disturbing vascular smooth muscle Ca2+signaling, diminishing endothelium-dependent vasorelaxation, and modifying the vascular response to vasoactive agonists. Moreover, lead has been shown to cause endothelial injury, impede endothelial repair, inhibit angiogenesis, reduce endothelial cell growth, suppress proteoglycan production, stimulate vascular smooth muscle cell proliferation and phenotypic transformation, reduce tissue plasminogen activator, and raise plasminogen activator inhibitor-1 production. Via these and other actions, lead exposure causes HTN and promotes arteriosclerosis, atherosclerosis, thrombosis, and cardiovascular disease. In conclusion, studies performed in experimental animals, isolated tissues, and cultured cells have provided compelling evidence that chronic exposure to low levels of lead can cause HTN, endothelial injury/dysfunction, arteriosclerosis, and cardiovascular disease. More importantly, these studies have elucidated the cellular and molecular mechanisms of lead's action on cardiovascular/renal systems, a task that is impossible to accomplish using clinical and epidemiological investigations alone.
Polymerized bovine hemoglobin decreases oxygen delivery during normoxia and acute hypoxia in the rat
Authors: Irwin David C. , Foreman Ben , Morris Ken , White Molly , Sullivan Tim , Jacobs Robert , Monnet Eric , Hackett Tim , TissotvanPatot Martha C. , Hamilton Karyn L. , Gotshall Robert W.
Published: June 2008

Hemoglobin-based oxygen carriers (HBOC) have been primarily studied for blood loss treatment. More recently infusions of HBOC in euvolemic subjects have been proposed for a wide variety of potential therapies in which increased tissue oxygenation would be beneficial. However, compared with the exchange transfusion models to study blood loss, less is known about HBOC oxygen delivery and vasoacitvity when it is infused in euvolemic subjects. We hypothesized that HBOC [polymerized bovine hemoglobin (PBvHb)] infusion creating hypervolemia would increase oxygen delivery to tissues during acute global hypoxia. Vascular oxygen content and hemodynamics were determined after euvolemic rats were infused with 3 ml of either lactated Ringer or PBvHb solution (13 g/dl, 1.3 g/kg) during acute hypoxia (FIO2 = 10%, 4 h) or normoxia (FIO2 = 21%) exposure. Our data demonstrated that compared with Ringer-infused animals, in hypoxia and normoxia, PBvHb treatment improved oxygen content but raised mean arterial pressure, lowered stroke volume, heart rate, and cardiac index, which resulted in a net reduction in blood flow and oxygen delivery to the tissues. The PBvHb vasoactive effect was similar in magnitude and direction as to the Ringer-infused animals treated with a nitric oxide synthase inhibitor nitro-l-arginine, suggesting the PBvHb effect is mediated via nitric oxide scavenging. We conclude that infusion of PBvHb is not likely to be useful in treating global hypoxia under these conditions.
Sex differences in control of blood pressure: role of oxidative stress in hypertension in females
Authors: Lopez-Ruiz Arnaldo , Sartori-Valinotti Julio , Yanes Licy L. , Iliescu Radu , Reckelhoff Jane F.
Published: June 2008

In general, blood pressure is higher in normotensive men than in age-matched women, and the prevalence of hypertension in men is also higher until after menopause, when the prevalence of hypertension increases for women. It is likely then that the mechanisms by which blood pressure increases in men and women with aging may be different. Although clinical trials to reduce blood pressure with antioxidants have typically not been successful in human cohorts, studies in male rats suggest that oxidative stress plays an important role in mediating hypertension. The exact mechanisms by which oxidative stress increases blood pressure have not been completely elucidated. There may be several reasons for the discrepancies between clinical and animal studies. In this review, the data obtained in selected clinical and animal studies are discussed, and the hypothesis is put forward that oxidative stress may not be as important in mediating hypertension in females as has been shown previously in male rats. Furthermore, it is likely that differences in genetics, age, length of time with hypertension, endothelial dysfunction, and sex are all factored in to modulate the responses to antioxidants in humans. As such, future clinical trials should be designed and powered to evaluate the effects of oxidative stress on blood pressure separately in men and women.
Tissue-specific downregulation of dimethylarginine dimethylaminohydrolase in hyperhomocysteinemia
Authors: Dayal Sanjana , Rodionov Roman N. , Arning Erland , Bottiglieri Teodoro , Kimoto Masumi , Murry Daryl J. , Cooke John P. , Faraci Frank M. , Lentz Steven R.
Published: June 2008

Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthase, has been proposed to be a mediator of vascular dysfunction during hyperhomocysteinemia. Levels of ADMA are regulated by dimethylarginine dimethylaminohydrolase (DDAH). Using both in vitro and in vivo approaches, we tested the hypothesis that hyperhomocysteinemia causes downregulation of the two genes encoding DDAH ( Ddah1 and Ddah2). In the MS-1 murine endothelial cell line, the addition of homocysteine decreased NO production but did not elevate ADMA or alter levels of Ddah1 or Ddah2 mRNA. Mice heterozygous for cystathionine β-synthase ( Cbs) and their wild-type littermates were fed either a control diet or a high-methionine/low-folate (HM/LF) diet to produce varying degrees of hyperhomocysteinemia. Maximal relaxation of the carotid artery to the endothelium-dependent dilator acetylcholine was decreased by ∼50% in Cbs+/− mice fed the HM/LF diet compared with Cbs+/+ mice fed the control diet ( P < 0.001). Compared with control mice, hyperhomocysteinemic mice had lower levels of Ddah1 mRNA in the liver ( P < 0.001) and lower levels of Ddah2 mRNA in the liver, lung, and kidney ( P < 0.05). Downregulation of DDAH expression in hyperhomocysteinemic mice did not result in an increase in plasma ADMA, possibly due to a large decrease in hepatic methylation capacity ( S-adenosylmethionine-to- S-adenosylhomocysteine ratio). Our findings demonstrate that hyperhomocysteinemia causes tissue-specific decreases in DDAH expression without altering plasma ADMA levels in mice with endothelial dysfunction.
Hepatic translation control in the late-gestation fetal rat
Authors: Gruppuso Philip A. , Tsai Shu-Whei , Boylan Joan M. , Sanders Jennifer A.
Published: June 2008

We have investigated the regulation of translation during the period of rapid liver growth that occurs at the end of gestation in the rat. This work was based on our prior observation that fetal hepatocyte proliferation is resistant to the inhibitory effects of rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR), a nutrient-sensing kinase that controls ribosome biogenesis and protein translation. We hypothesized that translation control in late-gestation fetal liver differs from that in adult liver. We first examined the ability of rapamycin to inhibit the translation of mRNAs encoding ribosomal proteins. Consistent with the effect of rapamycin on proliferation, the activation of adult liver 5′-terminal oligopyrimidine tracts (5′-TOP) translation that occurred during refeeding after food deprivation was sensitive to rapamycin. Fetal liver 5′-TOP translation was insensitive. We went on to examine the eukaryotic initiation factor (eIF) 4F cap-binding complex that controls global protein synthesis. The molecular weights of the multiple eIF4G1 isoforms present in fetal and adult liver eIF4F complexes differed. In addition, fetal liver expressed the eIF4A1 form of the eIF4A helicase, whereas adult liver contained eIF4A1 and eIF4A2. Rapamycin administration before refeeding in adult rats inhibited formation of the preinitiation complex to a much greater degree than rapamycin administration to fetal rats in situ. We conclude that there are major structural and functional differences in translation control between late-gestation fetal and adult liver. These differences may confer differential sensitivity to the growth inhibitory effects of rapamycin.
Behavioral Interactions Between Liris Nigra Van Der Linden(Hymenoptera: Sphecidae) and Gryllulus Domesticus L. (Orthoptera: Gryllidae)
Authors: Steiner A. L.
Published: June 2008

This study surveys and attempts to interpret the different behavioral
interactions between the solitary wasp Liris nigra V.d.L, and crickets
of the species Gryllulus domesticus L. in different hunting situations.
Significant variations are recorded, some of which are predictable,
others not. Wasp‐cricket interactions and responses become more
frequent, vigorous and complete from onset to peak of the hunting
phase. Discussion is concerned mainly with releasing conditions, with
characteristics and possible meaning of the interactions and responses.
The problem is placed in the context of general defense, alarm
reactions, predator‐prey interactions and possible corresponding
behavioral adaptations.
Ritual Jousting by Horned Parisoschoenus expositus Weevils (Coleoptera, Curculionidae, Baridinae)
Authors: Eberhard William G. , Garcia-C. J. Mauricio
Published: June 2008

Males of the weevil Parisoschoenus expositus use their prothoracic horns as weapons in stylized battles with other males over females that are drilling oviposition holes in palm leaves. The unusual sheath‐like structures that penetrate deep into the male prothorax function to receive the horns of opponents during battles. Horn size is dimorphic with respect to body size, and small and large males also differ behaviorally. Small males that have mated with a drilling female are sometimes able to impede a large male′s access to the female until after she has oviposited, but they are not able to take over females from larger males.