bluuebunny/crossref_metadata_2025 huggingface dataset:
Migraine With Aura Related to Closure of Atrial Septal Defects
Authors: Riederer Franz , Kaya Marihan , Christina Plank , Harald Gabriel , Peter Wessely
Published: June 2005

A 27‐year‐old woman had a history of migraine with aura (MWA) since aged 13 years with mostly two attacks per year. After transcutaneous closure of a secundum atrial septal defect (ASD) she suffered from almost daily recurring migraine attacks with prolonged aura symptoms. Exacerbation and new appearance of migraine attacks with aura after transcutaneous closure of ASD have been described previously.
Dissecting Aneurysm of the Basilar Artery as a Cause of Orgasmic Headache
Authors: Joo In Soo , Lee Jin Soo
Published: June 2005

A 39‐year‐old woman experienced recurrent, severe bursting headache which was abruptly developed at the time of orgasm. Both magnetic resonance angiography and conventional angiogram of the brain confirmed dissecting aneurysm of the basilar artery. After the neuroradiological intervention using a stent was performed, she has been totally free of the orgasmic headache during the follow‐up period for about one year.
Discourse, Party, and Policy: The Case of Abortion, 1965–1972
Authors: Nossiff Rosemary
Published: June 2005

The parameters of the contemporary abortion debate were established in the pre‐Roe period between 1965 and 1972, when groups and forces on the state and manual level competed to redefine the issue in order to pass new policies regulating it. This article traces the abortion politics of New York and Pennsylvania, the two states that led the nation in creating abortion policies before Roe, by looking at the relationship between the discourses created by various groups, the agree of party support they received, and the disparate policies that each state pawed as a result.
A Logistic Regression Model Explaining Recent State Casino Gaming Adoptions
Authors: Furlong Edward J.
Published: June 2005

The scholarly literature has argued that state fiscal stress, interstate tax competition, political feasibility, and economic development goals were the main reasons underlying the adoption of casino gaming by several American states. Archival data were collected and analyzed using logistic regression in an attempt to explain why some states have adopted casino gaming and others have not. Four statistically significant predictors of state casino gaming adoptions were discovered: moderate aggregate state ideological identifications, 1990 per capita tax rankings by state, longitudinal changes in state per capita taxes, and longitudinal changes in state job growth. These results suggest that motives related to political feasibility and economic development provide the best explanation of recent state casino gaming adoptions.
The Politics of Financial Services Liberalization: The Case of the Canadian Investment Dealer Industry
Authors: Harris Stephen L.
Published: June 2005

The purpose of this paper is to explain the factors and processes which, in 1986–87, gave rise to the decisions by the Canadian federal and provincial (Ontario and Quebec) regulatory authorities to liberalize entry into, and ownership of, the investment dealer industry in Canada. These decisions, rather narrowly based as they were, nonetheless would be a watershed with respect to the subsequent deregulation of the traditional four‐pillar structure of the Canadian financial services industry. The traditional four pillars‐which were legally and functionally separated‐comprised the chartered banks, the trust and mortgage loan companies, the life insurance industry, and the investment dealers. lhe liberalization decisions by the governments permitted the other elements of the four pillars, and nonresidents as well, to have equity participations in member firms of the securities industry. This represented a fundamental reversal of the beliefs, values, and ideas surrounding the low‐pillars doctrine. The period of history examined extends from 1969 to 1987.
The Price of Peace: A Predictive Model of UN Peacekeeping Fiscal Costs
Authors: Green David Michael , Kahl Chad , Diehl Paul F.
Published: June 2005

This study devised a predictive model of peacekeeping fiscal costs based on an analysis of all United Nations peacekeeping operations since 1945. Our results indicate that the costs of a peacekeeping operation were significantly influenced by the length of that mission and the size of the force deployed. Beyond these factors, the historical development from observer to second generation missions has produced more costly operation.
Disposing of the World's Excess Plutonium
Authors: McCormick James M. , Bullen Daniel B.
Published: June 2005

We undertake three key objectives in addressing the issue of plutonium disposition at the end of the Cold War. First, we estimate the total global inventory of plutonium both from weapons dismantlement and civil nuclear power reactors. Second, we review past and current policy toward handling this metal by the United States. Russia, and other key countries. Third, we evaluate the feasibility of several options (but especially the vitrification and mixed oxide fuel options announced by the Clinton administration) for disposing of the increasing amounts of plutonium available today.

To undertake this analysis, we consider both the political and scientific problems confronting policymakers in dealing with this global plutonium issue. Interview data with political and technical officials in Washington and at the International Atomic Energy Agency in Vienna. Austria, and empirical inventory data on plutonium from a variety of sources form the basis of our analysis.
Controversial Cleanup: Superfund and the Implementation of U.S. Hazardous Waste Policy
Authors: Rahm Dianne
Published: June 2005

While there is widespread public and political support for cleaning up the nation's hazardous waste sites, Superfund has been fraught with dissension and controversy since its inception. Some criticisms of the program focus on deriding an all‐too‐expensive program run amuck with litigation and federal heavy‐handedness. Other critics complain of an inefficient and ineffective program that has made painfully slow and inconsistent progress. Detractors do not disagree with the fundamental goal of the program—cleaning up hazardous waste sites. Rather, they focus on the fairness of Superfund's liability provisions and the Environmental Protection Agency's record of cleanup competency. This paper discusses these major issues at the core of the controversy over Superfund. The policy implications of Superfund program reform efforts and the ramifications for future hazardous waste policy are considered.
Coming Through a City Near You: The Transport of Hazardous Wastes
Authors: Falcone Santa , Orosco Kenneth
Published: June 2005

Current figures (compiled in 1995) indicate that hazardous waste transporters (19,567 in number) ship approximately 16 million tons of hazardous waste annually in the United States (United States Environmental Protection Agency, 1995). While some state and local governments have enacted hazardous waste transport regulations for the protection of their citizens, the federal government has had primacy in initiating and setting the course of hazardous waste transport regulation. As a result, the predominant perspective on hazardous waste transport has been technical in orientation. This paper identifies and discusses how this technical perspective and the social perspective differ and what the consequences are for government policies and actions regarding hazardous waste transport.
Book Notes
Authors: Carter‐Boone La Shonda
Published: June 2005

John C. Campbell and Naoki Ikegami, The Art of Balance in Health Policy Maintaining Japan's Low‐Cost, Egalitarian System.

Terry N. Clark and Vincent Hoffman‐Martinot (Eds.), The New Political Culture.

Susan E. Clarke and Gary L. Gailc, The Work of Cities.

Stephen E. Condrey (Ed.), Handhook of Human Resource Management in Government.

Timothy Conlan, From New Federalism to Devolution: Twency‐Five years of Intergovernmental Reform.

William M. Epstcin, Welfare in America: How Social Science Fails the Poor.

Malcolm M. Feeley and Edward L. Rubin, Judicial Policy Making und the Modern State: How the Courts Reformed America's Prisons.

Stephen J. McGovern, Politics of Downtown Development: Dynamic Political Cultures in San Francisco and Washington, DC.

William K. Nester, A Short History cf American Industrial Policies.

Richard J. Payne, Getting Beyond Race: The Changing American Culture.

Jon Pierre (Ed.), Partnerships in Urban Governance: European und American Experience.

Mark G. Popovich (Ed.), Creating High‐Performance Government Organizations.

Kalman Rupp and David C. Stapleton (Eds.), Growth in Disability Benefits: Explanations and Policy Implications.

Janie S. Steckenrider and Tonya M. Parrot (Eds.), New Directions in Old‐Age Policies.
Quantification of mast cells in different stages of human periodontal disease
Authors: Batista AC , Rodini CO , Lara VS
Published: June 2005

Objective and methods:  Among the cells involved in immune and inflammatory responses in periodontal disease, mast cells have been shown to be capable of generating a large number of biologically active substances. The present study was undertaken to identify and quantify the presence of mast cells in different stages of human periodontal disease using histochemical (toluidine blue) and immunohistochemical (tryptase‐positive mast cells) techniques.

Results:  Mast cell densities (cells per mm2) were significantly increased in chronic periodontitis/gingivitis lesions compared with clinically healthy gingival tissues (Health) uniquely by immunohistochemical technique. Interestingly, mast cells were distributed specially in close apposition to mononuclear cells.

Conclusions:  In human periodontal disease there is an increase in the number of mast cells that may be participating either in the destructive events or in the defense mechanism of periodontal disease via secretion of cytokines, including perpetuation of the Th2 response, and cellular migration and healing processes.
Number III Mucous membrane pemphigoid
Authors: Bagan J , Muzio LL , Scully C
Published: June 2005

Mucous membrane pemphigoid (MMP) is a sub‐epithelial vesiculobullous disorder. It is now quite evident that a number of sub‐epithelial vesiculobullous disorders may produce similar clinical pictures, and also that a range of variants of MMP exist, with antibodies directed against various hemidesmosomal components or components of the epithelial basement membrane. The term immune‐mediated sub‐epithelial blistering diseases (IMSEBD) has therefore been used. Immunological differences may account for the significant differences in their clinical presentation and responses to therapy, but unfortunately data on this are few. The diagnosis and management of IMSEBD on clinical grounds alone is impossible and a full history, general, and oral examination, and biopsy with immunostaining are now invariably required, sometimes supplemented with other investigations. No single treatment regimen reliably controls all these disorders, and it is not known if the specific subsets of MMP will respond to different drugs. Currently, apart from improving oral hygiene, immunomodulatory—especially immunosuppressive—therapy is typically used to control oral lesions. The present paper reviews pemphigoid, describing the present understanding of this fascinating clinical phenotype, summarising the increasing number of subsets with sometimes‐different natural histories and immunological features, and outlining current clinical practice.
Animal models of programming: early life influences on appetite and feeding behaviour
Authors: Langley‐Evans Simon C. , Bellinger Leanne , McMullen Sarah
Published: June 2005

Epidemiological observations of associations between early life nutrition and long‐term disease risk have prompted detailed experimental investigation of the biological basis of programming. Studies using rodent or large animal models have clearly established the biological plausibility of nutritional programming and are now yielding important information on underlying mechanisms. Nutritional interventions in pregnancy, including global food restriction, protein restriction, micronutrient restriction and excess fat feeding, determine a consistent cluster of disorders in the resulting offspring. The common association of such diverse nutritional disturbances with hypertension, glucose intolerance and adiposity suggests that a small number of simple common mechanisms are active in response to fetal nutrient imbalance. Studies of rodent models indicate that fetal undernutrition determines adult adiposity. It is unclear whether the increase in central adiposity is related to increased food intake or reduced energy expenditure, although evidence exists to suggest that both may act together. Rats subject to intrauterine protein restriction exhibit increased preference for high fat foods. Feeding of energy dense foods to rats that were undernourished in utero promotes a greater degree of obesity than is noted in animals subject to adequate nutrition in fetal life. There is evidence to suggest that programming of appetite may stem from remodelling of hypothalamic structures that control feeding and programming of the expression of genes involved in responses to orexogenic hormones. The early life programming of appetite and obesity is a complex phenomenon and our understanding of how maternal nutrition determines later energy balance is at a very early stage.
Childhood growth and chronic disease: evidence from countries undergoing the nutrition transition
Authors: Stein Aryeh D. , Thompson Angela M. , Waters Ashley
Published: June 2005

Evidence is accumulating that the pattern of growth in childhood is associated with development of cardiovascular disease in adulthood, but such evidence comes mostly from developed countries. We conducted a review of studies from countries undergoing the nutrition transition. Five birth cohorts with measures of child growth and outcomes through adolescence were identified, from China, India, Guatemala, Brazil and the Philippines. Across studies there are major differences in data availability and in statistical approaches to modelling child growth and its effects. Nevertheless, generally consistent associations of growth failure in early childhood and development of overweight in later childhood with the risk of elevated blood pressure, glucose, and serum lipids in adulthood were observed. As these cohorts mature they will provide a wealth of critical information on the relation between early life factors and later disease risk, and efforts should be made to ensure ongoing follow‐up using standardized approaches and more comprehensive assessments.
A Feasibility Study of Inverted Brayton Cycle for Gas Turbine Repowering
Authors: Bianchi M. , Negri di Montenegro G. , Peretto A. , Spina P. R.
Published: June 2005

In the paper a feasibility study of inverted Brayton cycle (IBC) engines, for the repowering of existing gas turbines, is presented. The following main phases have been carried out: (i) identification of the more suitable gas turbines to be repowered by means of an IBC engine; (ii) designing of the IBC components. Once the IBC engines for the candidate gas turbines were designed, an analysis has been developed to check the possibility to match these engines with other gas turbines, similar to those for which the IBC engines have been designed. In all the analyzed cases the evaluated performance result only slightly worse than that obtainable by repowering the same gas turbine with IBC engines ad hoc designed.
Hardware-in-the-Loop Simulation Study on the Fuel Control Strategy of a Gas Turbine Engine
Authors: Zhang, Huisheng , Su, and Ming , Weng Shilie
Published: June 2005

A hardware-in-the-loop simulation of a three-shaft gas turbine engine for ship propulsion was established. This system is composed of computers, actual hardware, measuring instruments, interfaces between actual hardware and computers, and a network for communication, as well as the relevant software, including mathematical models of the gas turbine engine. “Hardware-in-the-loop” and “volume inertia effects” are the two innovative features of this simulation system. In comparison to traditional methods for gas turbine simulation, the new simulation platform can be implemented in real time and also can test the physical hardware’s performance through their integration with the mathematical simulation model. A fuel control strategy for a three-shaft gas turbine engine, which can meet the requirement to the acceleration time and not exceeding surge line, was developed using this platform.
Models for the Prediction of Transients in Closed Regenerative Gas Turbine Cycles With Centrifugal Impellers
Authors: Korakianitis Theodosios , Vlachopoulos N. E. , Zou D.
Published: June 2005

This paper presents transient-flow component models for the prediction of the transient response of gas turbine cycles. The application is to predict the transient response of a small solar-powered regenerative gas-turbine engine with centrifugal impellers. The component sizes are similar to those under consideration for the solar-powered Space Station, but the models can easily be generalized for other applications with axial or mixed-flow turbomachinery. New component models for the prediction of the propagation of arbitrary transients in centrifugal impellers are developed. These are coupled with component models for the heat exchangers, receiver and radiator. The models are based on transient applications of the principles of conservation of mass, energy, and momentum. System transients driven by sinusoidal and double-step inputs in receiver salt temperature are presented and discussed. The new turbomachinery models and their coupling to the heat-exchanger models simulates disturbance-propagation in the components both upstream and downstream from the point of generation. This permits the study of the physical mechanisms of generation and propagation of higher-frequency contents in the response of the cycle.
Turbocharger-Design Effects on Gasoline-Engine Performance
Authors: Korakianitis Theodosios , Sadoi T.
Published: June 2005

Specification of a turbocharger for a given engine involves matching the turbocharger performance characteristics with those of the piston engine. Theoretical considerations of matching turbocharger pressure ratio and mass flow with engine mass flow and power permits designers to approach a series of potential turbochargers suitable for the engine. Ultimately, the final choice among several candidate turbochargers is made by tests. In this paper two types of steady-flow experiments are used to match three different turbochargers to an automotive turbocharged-intercooled gasoline engine. The first set of tests measures the steady-flow performance of the compressors and turbines of the three turbochargers. The second set of tests measures the steady-flow design-point and off-design-point engine performance with each turbocharger. The test results show the design-point and off-design-point performance of the overall thermodynamic cycle, and this is used to identify which turbocharger is suitable for different types of engine duties.
Laser-Based Investigations of Periodic Combustion Instabilities in a Gas Turbine Model Combustor
Authors: Giezendanner R. , Weigand P. , Duan X. R. , Meier W. , Meier U. , Aigner M. , Lehmann B.
Published: June 2005

The driving mechanism of pulsations in gas turbine combustors depends on a complex interaction between flow field, chemistry, heat release, and acoustics. Experimental data on all these factors are therefore required to obtain insight into the coupling mechanisms during a pulsation period. In order to develop a comprehensive experimental database to support a phenomenological understanding and to provide validation data for numerical simulation, a standard burner for optical investigations was established that exhibits strong self-excited oscillations. The burner was a swirl-stabilized nonpremixed model combustor designed for gas turbine applications and operated using methane as fuel at atmospheric pressure. It was mounted in a combustion chamber, which provides almost unobstructed optical access. The periodic combustion instabilities were studied by a variety of phase-resolved laser-based diagnostic techniques, locked to the frequency of the dominant pressure oscillation. Measurement techniques used were LDV for velocity measurements, planar laser-induced fluorescence for imaging of CH and OH radicals, and laser Raman scattering for the determination of the major species concentrations, temperature, and mixture fraction. The phase-resolved measurements revealed significant variations of all measured quantities in the vicinity of the nozzle exit, which trailed off quickly with increasing distance. A strong correlation of the heat release rate and axial velocity at the nozzle was observed, while the mean mixture fraction as well as the temperature in the periphery of the flame is phase shifted with respect to axial velocity oscillations. A qualitative interpretation of the experimental observations is given, which will help to form a better understanding of the interaction between flow field, mixing, heat release, and temperature in pulsating reacting flows, particularly when accompanied by corresponding CFD simulations that are currently underway.
Recent Developments in Turbomachinery Modeling for Improved Balancing and Vibration Response Analysis
Authors: Chen Peter Y. P. , Feng Ningsheng , Hahn Eric J. , Hu Wenlong
Published: June 2005

Present day turbogenerator installations are statically indeterminate rotor-bearing-foundation systems utilizing nonlinear hydrodynamic bearings. For optimal balancing and diagnostic purposes it is important to be able to correctly predict the system vibration behavior over the operating speed range. Essential aspects of this involve identifying the unbalance state, identifying appropriate dynamic foundation parameters, and identifying the system configuration state (relative location of the support bearings). This paper shows that, provided the system response is periodic at some speeds over the operating range and appropriate rotor and bearing housing motion measurements are made, it is possible, in principle, to satisfactorily achieve the above identifications without relying on the Reynolds equation for evaluating bearing forces. Preliminary results indicate that the identifications achieved promise to be superior to identification approaches that use the Reynolds equation.
Strain-Life Assessment of Grainex Mar-M 247 for NASA’s Turbine Seal Test Facility
Authors: Delgado Irebert R. , Halford Gary R. , Steinetz Bruce M. , Rimnac Clare M.
Published: June 2005

NASA’s turbine seal facility tests air-to-air seals for advanced jet engines. High temperature, speed, and pressure combinations limit test disk life, due to crack initiation in the Grainex Mar-M 247 disk bolt holes. An inspection interval is determined to ensure safe operation. Fatigue strain-life data is presented for test specimens from a test disk. Strain-life models (Manson-Hirschberg method of universal slopes, Halford-Nachtigall mean stress method, and modified Morrow method) were compared to experiment. Using experimental data at −99.95% prediction levels, accounting for six bolt holes at 0.5% total strain and 649°C, the test disk should be inspected after 665 cycles.
Suspension Synthesis for N:1 Roll Center Motion
Authors: Raghavan Madhusudan
Published: June 2005

A dimensional synthesis procedure to achieve prescribed roll center height variation of a vehicle’s sprung mass with respect to wheel jounce-rebound is presented. This may be used to size the relative lengths of the control arms of a short-long arm suspension mechanism in order to (i) fix the roll center with respect to ground, or (ii) fix the roll center relative to the sprung mass, or (iii) have the roll center move at a prescribed rate relative to the sprung mass, during wheel jounce-rebound. These design selections have a significant impact on the ride-handling characteristics of a vehicle. Numerical examples are provided to demonstrate the synthesis procedure.
A Curious New Family of Overconstrained Six-Bars
Authors: Baker J. Eddie
Published: June 2005

Discoveries of six-revolute spatial linkages have come about synthetically or intuitively rather than by analytical processes. The recognition of an anteriorly unknown case serendipitously incorporated in a new form of network has added a significant category to the existing tally of solutions. We demonstrate here that there are at least two other closely related loops. Further, the class can be generalized to a six-screw family. Unusual geometrical properties of the group are also investigated by means of displacement-closure equations and screw-motor algebra.
Optimal Synthesis of Mechanisms for Path Generation Using Refined Numerical Representation Based Model and AIS Based Searching Method
Authors: Liu Yong , Xiao Renbin
Published: June 2005

This paper presents an optimal synthesis method for path generation of planar mechanisms, in which a new path-description method named refined numerical representation is proposed to define the object function of the optimization model for path generation, and then the artificial immune network searching method is introduced to search candidate solutions. As a result, desired mechanisms can be generated independent of the scale, rotation, and translation transformation as well as sampling uniformity of initial sampling points. Experiment results demonstrate the effectiveness of the approach.
Influence of Tooth Profile Deviations on Helical Gear Wear
Authors: Kahraman A. , Bajpai P. , Anderson N. E.
Published: June 2005

In this study, a surface wear prediction model for helical gears pairs is employed to investigate the influence of tooth profile deviations in the form of intentional tooth profile modifications or manufacturing errors on gear tooth surface wear. The wear model combines a finite-element-based gear contact mechanics model that predicts contact pressures, a sliding distance computation algorithm, and Archard’s wear formulation to predict wear of the contacting tooth surfaces. Typical helical gear tooth modifications are parameterized by an involute crown, a lead crown, and an involute slope. The influence of these parameters on surface wear are studied within typical tolerance ranges achievable using hob/shave process. The results indicate that wear is related to the combined modification parameters of a gear pair rather than individual gear parameters. At the end, a design formula is proposed that relates the mismatch of contacting surface slopes to the maximum initial wear rate.
A Dual-Stage Planar Cable Robot: Dynamic Modeling and Design of A Robust Controller with Positive Inputs
Authors: Oh So-Ryeok , Mankala Kalyan , Agrawal Sunil K. , Albus James S.
Published: June 2005

Cable robots have potential usage for loading and unloading of cargo in shipping industries. A novel six-degrees-of-freedom two-stage cable robot has been proposed by NIST for skin-to-skin transfer of cargo. In this paper, we look at a planar version of this two-stage cable robot. The disturbance motion from the sea is considered while modeling the dynamics of robot. The problem of robust control of the end-effector in the presence of unknown disturbances, along with maintaining positive tensions in the cables, is tackled using redundancy of cables in the system. Simulation results show the effectiveness of the control strategy.
Algorithms for Involute and Octoidal Bevel-Gear Generation
Authors: Figliolini Giorgio , Angeles Jorge
Published: June 2005

A suitable formulation and the implementing algorithms for involute and octoidal bevel-gear generation are proposed in this paper. In particular, the exact spherical involute tooth profile of bevel gears and their crown rack is obtained through the pure-rolling motion of a great circle of the fundamental sphere on the base cone. Moreover, the tooth flank surface of octoidal bevel gears is obtained as the envelope of the tooth flat flank of the octoidal crown rack during the pure-rolling motion of its flat pitch (surface) on the pitch cone. The proposed algorithms have been implemented in MATLAB; several examples are included to illustrate their applicability.
Modeling of MEMS-Type Rankine Cycle Machines
Authors: Cui Ling , Brisson J. G.
Published: June 2005

Preliminary design and performance calculations for a silicon-based micro Rankine machine are discussed. The designs considered draw heat from a high temperature air stream with inlet temperatures between 770 and 1000K and reject heat to an ambient air stream at 300K. Most of the designs have a typical footprint of 6cm2. Water and benzene are considered as working fluids. Effects of the limits of heat exchanger and turbomachinery performance are analyzed and discussed. The designs of two types of heat exchangers (hole type and fin type) are described in detail. Their respective performances are compared. The calculations indicate that a machine with a 6cm2 footprint area is capable of delivering in excess of 40W of shaft power.
CASIMIR EFFECT AS A TEST FOR THERMAL CORRECTIONS AND HYPOTHETICAL LONG-RANGE INTERACTIONS
Authors: KLIMCHITSKAYA G. L. , DECCA R. S. , FISCHBACH E. , KRAUSE D. E. , LÓPEZ D. , MOSTEPANENKO V. M.
Published: June 2005

We have performed a precise experimental determination of the Casimir pressure between two gold-coated parallel plates by means of a micromachined oscillator. In contrast to all previous experiments on the Casimir effect, where a small relative error (varying from 1% to 15%) was achieved only at the shortest separation, our smallest experimental error (~ 0.5%) is achieved over a wide separation range from 170 nm to 300 nm at 95% confidence. We have formulated a rigorous metrological procedure for the comparison of experiment and theory without resorting to the previously used root-mean-square deviation, which has been criticized in the literature. This enables us to discriminate among different competing theories of the thermal Casimir force, and to resolve a thermodynamic puzzle arising from the application of Lifshitz theory to real metals. Our results lead to a more rigorous approach for obtaining constraints on hypothetical long-range interactions predicted by extra-dimensional physics and other extensions of the Standard Model. In particular, the constraints on non-Newtonian gravity are strengthened by up to a factor of 20 in a wide interaction range at 95% confidence.
BRANE GRAVITY AND CONFINEMENT OF TEST PARTICLES
Authors: JALALZADEH S. , SEPANGI H. R.
Published: June 2005

The confinement of classical and quantum test particles moving on a brane is studied by employing the notion of a returning force. It is shown that for classical test particles, the effects of extra dimensions are feeble whereas for quantum particles, these effects are pronounced. We also show that confinement causes the mass of a quantum particle to be quantized. Another consequence of the confinement is that it strongly restricts the choice of the bulk geometry even in the presence of the returning force.
TESTING THE NEWTON LAW AT LONG DISTANCES
Authors: REYNAUD SERGE , JAEKEL MARC-THIERRY
Published: June 2005

Experimental tests of Newton law put stringent constraints on potential deviations from standard theory with ranges from the millimeter to the size of planetary orbits. Windows however remain open for short range deviations, below the millimeter, as well as long range ones, of the order of or larger than the size of the solar system. We discuss here the relation between long range tests of the Newton law and the anomaly recorded on Pioneer 10/11 probes.
AN ELECTRIC CHARGE IN A GRAVITATIONAL FIELD
Authors: HARPAZ AMOS , SOKER NOAM
Published: June 2005

The interaction between a charge and its electric field are analyzed in different situatuations. It is found that whether the charge is accelerated and its electric field lags behind, or in the case where the charge is static and its electric field falls in a gravitational field — in both cases the electric field curves, a stress force is created that acts as a reaction force, and radiation is created.
SILENT UNIVERSES WITH A POSITIVE COSMOLOGICAL CONSTANT
Authors: VAN DEN BERGH NORBERT , WYLLEMAN LODE
Published: June 2005

The existence of inhomogeneous and algebraically general silent universes with a positive cosmological constant is demonstrated and explicit solutions are given when one of the eigenvalues of the expansion tensor is 0.
SPACE-TIME DEFECTS AS A SOURCE OF CURVATURE AND TORSION
Authors: TARTAGLIA ANGELO
Published: June 2005

Space time is described as a continuum four-dimensional medium similar to ordinary elastic continua. Exploiting the analogy internal stress states are considered. The internal "stress" is originated by the presence of defects. The defects are described according to the typical Volterra process. The case of a point defect in an otherwise isotropic four-dimensional medium is discussed showing that the resulting metric tensor corresponds to an expanding (or contracting) universe filled up with a non-zero energy-momentum density.
INFLATIONARY COSMOLOGY AND OSCILLATING UNIVERSES IN LOOP QUANTUM COSMOLOGY
Authors: MULRYNE DAVID J. , NUNES N. J. , TAVAKOL REZA , LIDSEY JAMES E.
Published: June 2005

We study oscillatory universes within the context of Loop Quantum Cosmology. We make a comparative study of flat and positively curved universes sourced by scalar fields with either positive or negative potentials. We investigate how oscillating universes can set the initial conditions for successful slow-roll inflation, while ensuring that the semi-classical bounds are satisfied. We observe rich oscillatory dynamics with negative potentials, although it is difficult to respect the semi-classical bounds in models of this type.
CASIMIR DENSITIES FOR A MASSIVE FERMIONIC QUANTUM FIELD IN A GLOBAL MONOPOLE BACKGROUND WITH SPHERICAL BOUNDARY
Authors: SAHARIAN A. A. , BEZERRA DE MELLO E. R.
Published: June 2005

We investigate the vacuum expectation value of the energy-momentum tensor associated with a massive fermionic field obeying the MIT bag boundary condition on a spherical shell in the global monopole spacetime. The asymptotic behavior of the vacuum densities is investigated near the sphere center and surface, and at large distances from the sphere. In the limit of strong gravitational field corresponding to small values of the parameter describing the solid angle deficit in global monopole geometry, the sphere-induced expectation values are exponentially suppressed.
BBN AND NEUTRINO OSCILLATIONS IN THE EARLY UNIVERSE: A BRIEF REVIEW
Authors: VILLANTE F. L.
Published: June 2005

We briefly review the physics of Big Bang Nucleosynthesis (BBN). We present, moreover, some recent results on active-sterile neutrino oscillations in the early universe and on their effects on BBN.
NONCOMMUTATIVE GEOMETRY AND THE STANDARD MODEL
Authors: SCHÜCKER THOMAS
Published: June 2005

Connes' noncommutative approach to the standard model of electromagnetic, weak and strong forces is sketched as well as its unification with general relativity.
SCALAR AND ELECTROMAGNETIC CONFIGURATIONS IN k = 1 FRIEDMANN–ROBERTSON–WALKER UNIVERSES
Authors: DARIESCU MARINA-AURA , DARIESCU CIPRIAN
Published: June 2005

The present work focuses on the scalar and electromagnetic fields in a spatially closed FRW Universe with incoherent dust. First, as the complex scalar field is under consideration, we derive the general solutions of the Gordon equation, in terms of the positive-frequency-like parity modes, and the corresponding propagator. Secondly, we turn to the source-free Maxwell equations in order to find a (1 + 4)-parametric class of closed form solutions representing a non-propagating fundamental electric field and a burst of electromagnetic radiation.
EFFECT OF SECONDARY PATH NONLINEARITY IN ACTIVE NOISE CONTROL SYSTEMS BEHAVIOR
Authors: TARINGOO F. , POSHTAN J. , KAHAEI M. H.
Published: June 2005

In this paper the behavior of an active noise control system is analyzed considering the nonlinearity of the secondary path transfer function. This nonlinearity may be due to actuator saturation in the operating condition. The statistical solution of the filter weighs adaptation and convergence behavior are obtained. It is shown that the degree of nonlinearity and the error estimation of secondary path transfer function can affect the transient and steady state behavior. The saturation function is considered as a nonlinear system in adaptive filter output. This function models saturation effects in active noise control systems when the acoustic transducers are driven by large-amplitude signals.
PUSHING THE ENVELOPE: Structure, Function, and Dynamics of the Nuclear Periphery
Authors: Hetzer Martin W. , Walther Tobias C. , Mattaj Iain W.
Published: June 2005

The nuclear envelope (NE) is a highly specialized membrane that delineates the eukaryotic cell nucleus. It is composed of the inner and outer nuclear membranes, nuclear pore complexes (NPCs) and, in metazoa, the lamina. The NE not only regulates the trafficking of macromolecules between nucleoplasm and cytosol but also provides anchoring sites for chromatin and the cytoskeleton. Through these interactions, the NE helps position the nucleus within the cell and chromosomes within the nucleus, thereby regulating the expression of certain genes. The NE is not static, rather it is continuously remodeled during cell division. The most dramatic example of NE reorganization occurs during mitosis in metazoa when the NE undergoes a complete cycle of disassembly and reformation. Despite the importance of the NE for eukaryotic cell life, relatively little is known about its biogenesis or many of its functions. We thus are far from understanding the molecular etiology of a diverse group of NE-associated diseases.
Drosophila as a Model for Human Neurodegenerative Disease
Authors: Bilen Julide , Bonini Nancy M.
Published: June 2005

Among many achievements in the neurodegeneration field in the past decade, two require special attention due to the huge impact on our understanding of molecular and cellular pathogenesis of human neurodegenerative diseases. First is defining specific mutations in familial neurodegenerative diseases and second is modeling these diseases in easily manipulable model organisms including the fruit fly, nematode, and yeast. The power of these genetic systems has revealed many genetic factors involved in the various pathways affected, as well as provided potential drug targets for therapeutics. This review focuses on fruit fly models of human neurodegenerative diseases, with emphasis on how fly models have provided new insights into various aspects of human diseases.
Dr. Bernice Grafstein’s paper on the mechanism of spreading depression
Authors: Strong Anthony J.
Published: June 2005

This essay looks at the historical significance of one APS classic paper that is freely available online:

Grafstein B. Mechanism of spreading cortical depression. J Neurophysiol 19: 154–171, 1956 ( http://jn.physiology.org/cgi/reprint/19/2/154 ).
Thalamocortical Specificity and the Synthesis of Sensory Cortical Receptive Fields
Authors: Alonso Jose-Manuel , Swadlow Harvey A.
Published: June 2005

A persistent and fundamental question in sensory cortical physiology concerns the manner in which receptive fields of layer-4 neurons are synthesized from their thalamic inputs. According to a hierarchical model proposed more than 40 years ago, simple receptive fields in layer 4 of primary visual cortex originate from the convergence of highly specific thalamocortical inputs (e.g., geniculate inputs with on-center receptive fields overlap the on subregions of layer 4 simple cells). Here, we summarize studies in the visual cortex that provide support for this high specificity of thalamic input to visual cortical simple cells. In addition, we review studies of GABAergic interneurons in the somatosensory “barrel” cortex with receptive fields that are generated by a very different mechanism: the nonspecific convergence of thalamic inputs with different response properties. We hypothesize that these 2 modes of thalamocortical connectivity onto subpopulations of excitatory and inhibitory neurons constitute a general feature of sensory neocortex and account for much of the diversity seen in layer-4 receptive fields.
Modest Salt Reduction Reduces Blood Pressure and Urine Protein Excretion in Black Hypertensives
Authors: Swift Pauline A. , Markandu Nirmala D. , Sagnella Giuseppe A. , He Feng J. , MacGregor Graham A.
Published: June 2005

High blood pressure and proteinuria are the major risk factors for cardiovascular and renal disease. In black individuals, there is an increased risk of hypertension, stroke, heart failure, and kidney disease. There are no controlled studies of the effects of reducing salt intake on blood pressure and urine protein excretion in black individuals. Therefore, the aim of our study was to determine the effects of modest salt restriction on blood pressure and urine protein excretion in nondiabetic black hypertensive subjects. The study was randomized, double blind, and placebo controlled. After run-in periods on their usual diet and on reduced salt, participants continued to restrict their salt intake and then received either slow sodium tablets, designed to bring their salt intake back to normal, or placebo tablets for 4 weeks in a randomized, double-blind, crossover study. In the 40 who completed the study, urinary sodium excretion fell on slow sodium to placebo from 169±73 to 89±52 mmol per 24 hours (
P
<0.001; ≈10 to 5 g salt per day). Blood pressure fell from 159/101±13/8 to 151/98±13/8 mm Hg (
P
<0.01). Protein excretion fell from 93±48 mg to 75±30 mg per 24 hours (
P
<0.008). Thus, reducing salt intake from ≈10 to 5 g per day reduced blood pressure and urine protein excretion in black hypertensives. In light of these findings, we would recommend that all black individuals with raised blood pressure reduce their salt intake to ≤5 g per day.
Neuronal Nitric Oxide Synthase Mediates Statin-Induced Restoration of Vasa Nervorum and Reversal of Diabetic Neuropathy
Authors: Ii Masaaki , Nishimura Hiromi , Kusano Kengo F. , Qin Gangjian , Yoon Young-sup , Wecker Andrea , Asahara Takayuki , Losordo Douglas W.
Published: June 2005

Background—

Peripheral neuropathy is a frequent and major complication of diabetes.

Methods and Results—

Severe peripheral neuropathy developed in type II diabetic mice, characterized by significant slowing of motor and sensory nerve conduction velocities. Rosuvastatin restored nerve vascularity, including vessel size, and nerve function also recovered to the levels of nondiabetic mice. Neuronal nitric oxide synthase expression in sciatic nerves was reduced in diabetic mice but was preserved by rosuvastatin. Coadministration of a nitric oxide synthase inhibitor with rosuvastatin attenuated the beneficial effects of rosuvastatin on nerve function and limited the recovery of vasa nervorum and nerve function. In vitro, rosuvastatin inhibited downregulation of neuronal nitric oxide synthase expression induced by high-glucose conditions in cultured Schwann cells. Furthermore, Akt phosphorylation in Schwann cells, downregulated by high-glucose conditions, was also restored by rosuvastatin, consistent with the change of neuronal nitric oxide synthase expression. Akt inhibition independently reduced neuronal nitric oxide synthase expression in Schwann cells in low-glucose cultures.

Conclusions—

These data indicate that the HMG-CoA reductase inhibitor rosuvastatin has a favorable effect on diabetic neuropathy independent of its cholesterol-lowering effect. Our data provide evidence that this effect may be mediated in part via neuronal nitric oxide synthase/nitric oxide and phosphatidylinositol 3-kinase/Akt-signaling pathways and also suggest that restoration or preservation of the microcirculation of the sciatic nerve may be involved.
Augmented Cardiac Hypertrophy in Response to Pressure Overload in Mice Lacking the Prostaglandin I
2
Receptor
Authors: Hara Akiyoshi , Yuhki Koh-ichi , Fujino Takayuki , Yamada Takehiro , Takayama Koji , Kuriyama Shuhko , Takahata Osamu , Karibe Hideji , Okada Yuji , Xiao Chun-Yang , Ma Hong , Narumiya Shuh , Ushikubi Fumitaka
Published: June 2005

Background—

In the heart, the expressions of several types of prostanoid receptors have been reported. However, their roles in cardiac hypertrophy in vivo remain unknown. We intended to clarify the roles of these receptors in pressure overload–induced cardiac hypertrophy using mice lacking each of their receptors.

Methods and Results—

We used a model of pressure overload–induced cardiac hypertrophy produced by banding of the transverse aorta in female mice. In wild-type mice subjected to the banding, cardiac hypertrophy developed during the observation period of 8 weeks. In mice lacking the prostaglandin (PG) I
2
receptor (IP
−/−
), however, cardiac hypertrophy and cardiomyocyte hypertrophy were significantly greater than in wild-type mice at 2 and 4 weeks but not at 8 weeks, whereas there was no such augmentation in mice lacking the prostanoid receptors other than IP. In addition, cardiac fibrosis observed in wild-type hearts was augmented in IP
−/−
hearts, which persisted for up to 8 weeks. In IP
−/−
hearts, the expression level of mRNA for atrial natriuretic peptide, a representative marker of cardiac hypertrophy, was significantly higher than in wild-type hearts. In vitro, cicaprost, an IP agonist, reduced platelet-derived growth factor–induced proliferation of wild-type noncardiomyocytes, although it could not inhibit cardiotrophin-1–induced hypertrophy of cardiomyocytes. Accordingly, cicaprost increased cAMP concentration efficiently in noncardiomyocytes.

Conclusions—

IP plays a suppressive role in the development of pressure overload–induced cardiac hypertrophy via the inhibition of both cardiomyocyte hypertrophy and cardiac fibrosis. Both effects have been suggested as originating from the action on noncardiomyocytes rather than cardiomyocytes.
A Stochastic Model for the Spatial Structure of Annular Patterns of Variability and the North Atlantic Oscillation
Authors: Gerber Edwin P. , Vallis Geoffrey K.
Published: June 2005

Meridional dipoles of zonal wind and geopotential height are found extensively in empirical orthogonal function (EOF) analysis and single-point correlation maps of observations and models. Notable examples are the North Atlantic Oscillation and the so-called annular modes (or the Arctic Oscillation). Minimal stochastic models are developed to explain the origin of such structure. In particular, highly idealized, analytic, purely stochastic models of the barotropic, zonally averaged zonal wind and of the zonally averaged surface pressure are constructed, and it is found that the meridional dipole pattern is a natural consequence of the conservation of zonal momentum and mass by fluid motions. Extension of the one-dimensional zonal wind model to two-dimensional flow illustrates the manner in which a local meridional dipole structure may become zonally elongated in EOF analysis, producing a zonally uniform EOF even when the dynamics is not particularly zonally coherent on hemispheric length scales. The analytic system then provides a context for understanding the existence of zonally uniform patterns in models where there are no zonally coherent motions. It is also shown how zonally asymmetric dynamics can give rise to structures resembling the North Atlantic Oscillation. Both the one- and two-dimensional results are manifestations of the same principle: given a stochastic system with a simple red spectrum in which correlations between points in space (or time) decay as the separation between them increases, EOF analysis will typically produce the gravest mode allowed by the system’s constraints. Thus, grave dipole patterns can be robustly expected to arise in the statistical analysis of a model or observations, regardless of the presence or otherwise of a dynamical mode.