bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation of vortical structures in a jet diffusion flame
Authors: Goss L.P. , Katta V.R. , Roquemore W.M.
Published: September 2004

The dynamics of a transitional propane jet diffusion flame with a fuel‐jet velocity of 2.2 m/s has been studied using an implicit, third‐order‐accurate, upwind numerical scheme. The large‐scale vortices outside the flame surface and the small‐scale ones inside were simulated simultaneously, and their interactions with the flame surface were investigated. Numerical experiments were conducted to gain insight into the influence of buoyancy and shear‐layer forcing on the development of the outer and inner vortices. In the presence of buoyancy forces, the outer vortices developed as part of the solution, and the vortex‐crossing frequency was approximately 15 Hz. The inner structures were manifested from a weak perturbation the vorticity that was introduced at the nozzle exit, and, at 185 Hz, these vortices were found to travel farther downstream. It was also found that the inner vortices do not play a role in the formation of the outer vortices, and vice versa. However, the growth of the inner vortices in the downstream locations is strongly influenced by the slowly moving outer vortices.
Optimal regularization of the inverse‐heat conduction problem
using the L‐curve
Authors: Trujillo David M. , Busby Henry R.
Published: September 2004

Solving the inverse heat conduction using Tikhonov regularization
requires the selection of an optimal smoothing parameter. One popular method
for choosing the smoothing parameter is the generalized
cross‐validation method. This method works very well but is
computationally expensive. In this paper we investigate the L‐curve
method for selecting an optimal smoothing parameter. This L‐curve is
easily computed and may prove very useful for large systems which preclude
other methods.
Turbulent natural convection in a sidewall‐heated cavity using a
two‐equation model of temperature
Authors: Fusegi Toru
Published: September 2004

A calculation procedure for turbulent natural convection in enclosures
is described. A two‐equation model based on the eddy diffusivity
concept for the temperature field possessing a form similar to the
k—ε model of flow is incorporated, thus, extending the
applicability of the eddy diffusivity models by removing constraints of the
Reynolds analogy between momentum and thermal transport processes. As a test
problem, natural convection in a square cavity subjected to differential
side‐wall heating is analysed. The vertical walls are divided into
isothermal and constant heat‐flux surfaces and heated
non‐uniformly. AtRa = 1010 and for an
air—filled cavity (Pr = 0.71), variations of heating
patterns are found to significantly alter the field characteristics. Numerical
predictions demonstrate dissimilar features of the velocity and temperature
fluctuations.
A coupled model for water flow, airflow and heat flow in deformable porous media
Authors: Schrefler Bernard A. , Zhan Xiaoyong , Simoni Luciano
Published: September 2004

A fully coupled numerical model to simulate the complex
behaviour of soil deformation, water flow, airflow, and heat
flow in porous media is developed. The following thermal effects
are taken into account: heat transfer through conduction and
convection, flow, as well as viscosity and density variation of
the fluids due to temperature gradients. The governing equations
in terms of soil displacements, water and air pressures, and
temperature are coupled non‐linear partial differential
equations and are solved by the finite element method. Two
examples are presented to demonstrate the model
performances.
A numerical study of transient natural convection about a corrugated
plate embedded in an enclosed porous medium
Authors: Hsiao Shih‐Wen
Published: September 2004

The problems of transient natural convection from a corrugated plate
embedded in an enclosed porous medium is studied numerically. The non‐Darcian
effects as well as the acceleration terms are taken into consideration in the
momentum equation. The governing equations in terms of vorticity, stream
function and temperature are expressed in a body‐fitted coordinates system,
which were solved numerically by the finite difference method. Results are
presented in terms of streamlines and isotherms, local and average Nusselt
numbers, with Darcy‐Rayleigh number ranging from 0 to 1000, and Darcy number
from 10–4 to 10–1, for several aspect ratios of the
cavity and plate positions. The flow and heat transfer characteristics for a
corrugated plate and a flat plate and the numerical results solved with four
different mathematical models are also compared.
Simulation of ice cover melting in turbulent flow
Authors: Saadé Raafat G. , Sarraf Semaan
Published: September 2004

In Northern Regions, ice covers that form on rivers, streams, and lakes
with the onset of winter, cause various problems related to winter navigation
and pollution dispersion among others. Warm water, from industrial plants,
discharged into these rivers cause partial or total melting of the ice cover
over considerable distances. The present work investigates the melting of a
thin non‐uniform ice cover subject to varying water and air temperatures
under turbulent flow conditions. A two‐dimensional depth averaged turbulence
model coupled with a heat transfer model is used to simulate laboratory
conditions of ice cover melting. Computational results were compared with
experimental investigations. The average melting of the ice cover was found
to be in close agreement with the experimental measurements with the
exception of the leading edge region.
On the determination of heat transfer coefficient between pvc and steel
in vacuum extrusion calibrators
Authors: Fradette L. , Tanguy P.A. , Hurez P. , Blouin D.
Published: September 2004

The design of vacuum calibrators for the cooling of complex PVC profiles
is central to the production of high quality extrudates. One important
parameter governing cooling efficiency is the heat transfer coefficient at
the interface between the stainless steel calibrator and the PVC extrudate,
whose value is often taken as constant regardless of the extrusion velocity
and the applied pressure vacuum. In this paper, a method is proposed to
evaluate the variation of the heat transfer coefficient over the entire
calibrator length. The idea is to use temperature measurements together with
heat transfer simulation to derive a heat transfer correlation that can be
used in practical design cases.
A new approach for linear stability analysis
Authors: Shi J.
Published: September 2004

This paper investigates the issue of linear stability analysis for two
and three level explicit and implicit one‐dimensional finite different
numerical schemes. A new approach which is based on the von Neumann method
method is presented. This approach was validated by testing some popular
numerical schemes.
Solution of steady inviscid subsonic flow by a locality analytic
method
Authors: Montgomery Matthew , Fleeter Sanford
Published: September 2004

The first compressible flow solution based solely on the locally
analytical method is developed. This is accomplished by developing the flow
model and locally analytical solution for inviscid subsonic compressible
flow. The stream function for irrotational, compressible flow without body
forces was chosen as the governing differential equation. To demonstrate the
modelling and locally analytical solution, this analysis is then applied to
predict the flow in convergent nozzles, both planar and axially symmetric,
for different back pressures. Results are presented which demonstrate the
effectiveness of this technique.
Vectorized strongly implicit solving procedure for a seven‐diagonal
coefficient matrix
Authors: Leister H. –J. , Perić M.
Published: September 2004

The paper presents an extension of Stone’s1 strongly implicit
procedure for solving linear equation systems resulting from the
discretization of partial differential equations to three‐dimensional
problems. The solver is applicable to seven‐diagonal coefficient
matrices, as are obtained when central‐difference approximations are
used for discretization. The algorithm is implemented in a way which allows
vector processing on modern supercomputers, in spite of its recursive
structure. Other solvers, using incomplete lower‐upper decomposition
(ILU), can be vectorized in the same way. Test calculations show
solver performance of about 150 Mflops on CRAY—YMP and over 200 Mflops
on FUJITSU—VP200 computers. A listing of the FORTRAN code is
provided.
A multiphase formulation for two phase flows
Authors: Daniel E. , Saurel R. , Larini M. , Loraud J.C.
Published: September 2004

This paper investigates the multi‐phase behaviour of droplets
injected into a nozzle at two separate wall locations. The physical features
of the droplets (rate of mass, density and radius) at each injector
location are identical. This system can be described by a two‐phase
Eulerian—Eulerian approach that yields classical systems of
equations: three for the gaseous phase and three for the dispersed
droplet phase. An underlying assumption in the two phase model is that no
interaction occurs between droplets. The numerical solution of the model
(using the MacCormack scheme) indicates however that the opposite
jets do interact to form one jet. This inconsistency is overcome in the
current paper by associating the droplets from a given injection location
with a separate phase and subsequently solving equations describing a
multiphase system (here, three‐phase system). Comparison of
numerical predications between the two‐phase and the multiphase model
shows significantly different results. In particular the multiphase model
shows no jet interaction.
A numerical study on turbulent couette flow and heat transfer in concentric annuli
Authors: Torii S. , Yang W. ‐J.
Published: September 2004

A theoretical study is performed to investigate turbulent flow and heat
transfer characteristics in a concentric annulus with a heated inner cylinder
moving in the direction of flow (Couette flow). The
two‐equation k‐ε model is employed to determine turbulent
viscosity and kinetic energy. The Reynolds stress and turbulent heat flux are
expressed by Boussinesq’s approximation. The governing boundary‐layer
equations are discretized by means of a control volume
finite‐difference technique and numerically solved using a marching
procedure. Results are obtained for the time‐averaged streamwise
velocity profile, turbulent kinetic energy profile, friction factor, and
Nusselt number. These results agree well with experimental data in the
existing literature. It is concluded from the study that the streamwise
movement of the inner wall induces an attenuation in the turbulent kinetic
energy, resulting in a reduction in the heat transfer performance and an
increase in the velocity ratio of the moving inner cylinder to the fluid flow
causes a substantial decrease in both the friction factor and the Nusselt
number as well as a drastic reduction in the turbulent kinetic energy in the
inner wall region.
A boundary element method for the solution of convective diffusion and
burgers’ equations
Authors: Grigor’ev Michael M.
Published: September 2004

The paper gives the description of boundary element method
(BEM) with subdomains for the solution of
convection—diffusion equations with variable coefficients and Burgers’
equations. At first, the whole domain is discretized into K subdomains, in
which linearization of equations by representing convective velocity by the
sum of constant and variable parts is carried out. Then using fundamental
solutions for convection—diffusion linear equations for each subdomain
the boundary integral equation (in which the part of the convective term
with the constant convective velocity is not included into the
pseudo‐body force) is formulated. Only part of the convective
term with the variable velocity, which is, as a rule, more than one order
less than convective velocity constant part contribution, is left as the
pseudo‐source. On the one hand, this does not disturb the numerical
BEM—algorithm stability and, on the other hand, this leads to
significant improvement in the accuracy of solution. The global matrix,
similar to the case of finite element method, has block band structure
whereas its width depends only on the numeration order of nodes and
subdomains. It is noted, that in comparison with the direct boundary element
method the number of global matrix non‐zero elements is not
proportional to the square of the number of nodes, but only to the total
number of nodal points. This allows us to use the BEM for the solution of
problems with very fine space discretization. The proposed BEM with
subdomains technique has been used for the numerical solution of
one‐dimensional linear steady‐state convective—diffusion
problem with variable coefficients and one‐dimensional
non‐linear Burgers’ equation for which exact analytical solutions are
available. It made it possible to find out the BEM correctness
according to both time and space. High precision of the numerical method is
noted. The good point of the BEM is the high iteration convergence,
which is disturbed neither by high Reynolds numbers nor by the presence of
negative velocity zones.
Integral transform method for boundary layer equations in simultaneous
heat and fluid flow problems
Authors: Machado H.A. , Cotta R.M.
Published: September 2004

The two‐dimensional steady boundary layer equations, for
simultaneous heat and fluid flow within ducts, are handled through the
generalized integral transform technique. The momentum and energy equations
are integral transformed by eliminating the transversal coordinate and
reducing the PDE’s into an infinite system of coupled non‐linear
ordinary differential equations for the transformed potentials. An adaptively
truncated version of this ODE system is numerically handled through well
known initial value problem solvers, with automatic precision control
procedures. The explicit inversion formulae are then recalled to provide
analytic expressions for velocity and temperature fields and related
quantities of practical interest. Typical examples are presented in order to
illustrate the hybrid numerical analytical approach and its convergence
behaviour.
Modelling dump combustor flows with and without swirl at the inlet using
Reynolds stress models
Authors: Tsai J.H. , LIN C.A. , LU C.M.
Published: September 2004

Numerical simulations were applied to suddenly‐expanding‐pipe flows,
with and without swirl at the inlet, using an eddy‐viscosity type k‐ε model
and Reynolds stress transport model variants. The predicted mean and
turbulence results were compared with measurements. For the non‐swirling
case, the flowfield was well represented by all the models, though the
k‐ε predictions showed a slightly higher level of radial diffusive
transport across the shear layer in the recirculation zone. As for the weakly
swirling case, while all models, especially the stress models, give accurate
values of the mean flow and turbulence fields in regions remote from the
central vortex core; the biggest discrepancies between predictions and
measurements occurred along the centreline in which all the models failed to
reproduce correctly the strength of the decay of swirl‐induced deceleration
of the axial velocity. The intensity of the turbulence along the centreline
was also severely underpredicted by all the models and this contributed to
the misrepresentations of the shear stresses and, hence, the mean flow
development predicted by the stress models.
A PDF description of turbulent plane couette flow
Authors: Hong Zuu‐Chang , Lin Ching , Chen Ming‐Hua
Published: September 2004

A transport equation for the one‐point velocity probability density
function (pdf) of turbulence is derived, modelled and solved. The new pdf
equation is obtained by two modeling steps. In the first step, a dynamic
equation for the fluid elements is proposed in terms of the fluctuating part
of Navier‐Stokes equation. A transition probability density function (tpdf)
is extracted from the modelled dynamic equation. Then the pdf equation of
Fokker‐Planck type is obtained from the tpdf. In the second step, the
Fokker‐Planck type pdf equation is modified by Lundgren’s formal pdf equation
to ensure it can properly describe the turbulence intrinsic mechanism. With
the new pdf equation, the turbulent plane Couette flow is solved by the
direct finite difference method coupled with dimensionality reduction and
QUICKER scheme. A simple boundary treatment is proposed such that the
near‐wall solution is tractable and then no refined grid is required. The
calculated mean velocity, friction coefficient, and turbulence structure are
in good agreement with available experimental data. In the region departed
from the center of flow field, the contours of isojoint pdf of V1 and
V2 is very similar to that of experimental result of channel flow.
These agreements show the validity of the new pdf model and the availability
of the boundary treatment and QUICKER scheme for solving the turbulent plane
Couette flow.
Oscillatory flow convection in a melted pool
Authors: Morvan D. , Bournot Ph.
Published: September 2004

A two‐dimensional laser surface remelting problem is numerically
simulated. The mathematical formulation of this multiphase problem is
obtained using a continuum model, constructed from classical mixture theory.
This formulation permits the construction of a set of continuum conservation
equations for pure or binary, solid‐liquid phase change systems. The
numerical resolution of this set of coupled partial differential equations is
performed using a finite volume method associated with a PISO algorithm. The
numerical results show the modifications caused by an increase of the free
surface shear stress (represented by the Reynolds number Re) upon
the stability of the thermocapillary flow in the melting pool. The solutions
exhibit a symmetry‐breaking flow transition, oscillatory behaviour at higher
values of Re. Spectral analysis of temperature and velocity signals
for particular points situated in the melted pool, show that these
oscillations are at first mono‐periodic them new frequencies appear
generating a quasi‐periodic behaviour. These oscillations of the flow in the
melted pool could induce the deformation of the free surface which in turn
could explain the formation of surface ripples observed during laser surface
treatments (surface remelting, cladding) or laser welding.
Differential teamwork performance
Authors: Weisberg Jacob
Published: September 2004

Team‐based, performance‐contingent pay plans are designed to increase workers’ motivation and productivity. Evaluates differential performance among 65 workers employed in 20 teamwork groups in a public‐sector organization. Study results are in two directions: first, introduction of an incentive scheme increased productivity by 14 per cent. Second, differential teamwork performance is affected by tenure and education. Finds tenure, which represents “firm‐specific human capital” and years of schooling representing “general human capital”, are positive and significant in both a bivariate Pearson correlation and in multivariate regression analysis. An interaction effect of tenure and education was not found to be significant, probably due to colinearity problems. Discusses results from both labour economics and social psychology perspectives.
Future age‐conscious manpower planning in The Netherlands
Authors: Ekamper P.
Published: September 2004

The population of The Netherlands will, as in other industrialized countries, continue to age in the coming decades. So far, the working‐age population has not been affected, but the ageing process is set to leave its mark on the labour force in the next 25 years. An ageing labour force and possible future policy measures in this area will have important repercussions for individual organizations. Research into future trends has shown that the percentage of people aged over 50 in public service will increase from 15 per cent in 1995 to 35 per cent in 2010. Policy measures aimed at stimulating the labour force participation of the elderly will boost this percentage even further. The elderly employees not only hold the highest positions, but also they withdraw from the workforce in limited numbers. Unless the number of jobs is increased, opportunities for promotion and entry into the Civil Service are likely to decline. The only way to counteract an ageing workforce ‐ even if only to a limited degree ‐ is to encourage the retirement of elderly employees and/or to significantly boost the number of jobs within the organization. Such measures would run counter to current political trends. An alternative would be to reassess the position of the elderly within the organization.
Certification
Authors: Wright Phillip C.
Published: September 2004

Charts an alternative training method for both traditional and emerging vocational occupations. As Canadians see themselves as belonging to the middle class, apprenticeships have never been popular in Canada. Moreover, the Canadian business sector, in the throes of downsizing, will not make long‐term commitments to employees. Proposes, therefore, that certification systems may be the answer to Canada’s ongoing skills shortage.
Memetics: a new paradigm for understanding customer behaviour and influence
Authors: Marsden Paul S.
Published: September 2004

The objective of this paper is to provide a non‐technical introduction to the science of memetics and to suggest how this new discipline may be applied to the design and development of effective marketing campaigns. The technique is based on a neo‐Darwinian evolutionary model of information transmission that may be used to explain and predict the “infectiousness” of certain ideas and behaviours. It is argued that traditional marketing theories based on rational choice theory may rely on an impossible homuncular psychology and it is suggested that a viable alternative would be to understand customer behaviour from a memetic perspective ‐ the result of contagion rather than conscious choice. From the memetic paradigm the role of marketing communications becomes one of designing and engineering infectious “mind viruses” that will influence customer perceptions and behaviour. Whilst memetics is still in its infancy, it is suggested that memetic engineering may provide a viable and effective complementary framework to standard techniques for developing successful marketing strategies.
The Times They Are A’Changin’: Students, Technology, and Instructional Services
Authors: Dupuis Elizabeth A.
Published: September 2004

Although technology vies for our attention–continually creating new opportunities and challenges for library instruction–we must remain focused on our students. Recent studies indicate that the current generation of students is more comfortable than previous generations with online active learning environments and has seamlessly integrated the Internet into their everyday lives. In this article, Dupuis examines trends and uses anecdotes from her personal experience to illuminate the implications for instructional programs. It is time, she asserts, to reassess current approaches, content, instructional design, and evaluation techniques. To be successful, it is important to listen to students, challenge the status quo, and take risks.
Situational strategies
Authors: Rigby Darrell K.
Published: September 2004

To win in turbulence, senior executives must continually review three dimensions of their business context: their industry’s source and level of turbulence, their own strategic position within their sector, and their financial strength. The author reports on a study that suggests that there is a significant opportunity to win in turbulence. The companies that were prepared for bad times captured a disproportionate share of industry growth and profits. These companies had developed situational strategies that could be called upon immediately when the market changed. The article describes the key steps in developing and implementing these alternative strategic moves.
Testing Explanations of Strategic Voting in Legislatures: A Reexamination of the Compromise of 1790
Authors: Clinton Joshua D. , Meirowitz Adam
Published: September 2004

A difficult yet prevalent problem in legislative politics is how to assess explanations when observable actions may not represent true (and unobserved) legislator preferences. We present a method for analyzing the validity of theoretical/historical accounts that unifies theory, history, and measurement. We argue that approaches to testing accounts of legislative behavior which are theoretically and historically agnostic are not always best and present an approach which: (1) forms an explicit explanation of behavior (here a simple dynamic voting game) that yields estimable parameter constraints, and (2) tests these constraints using a customized empirical model that is as consistent as possible with the explanation. We demonstrate the method using legislative voting data from the first Congress (1789–1791). Using the idea of sophisticated equivalents from voting theory we subject the traditional account of the “Compromise of 1790” to a statistical test and find that there is reason to doubt the claim that legislators of the time believed the specified log roll was taking place. The results suggest that the capital location and assumption issues were resolved independently.
The Political (and Economic) Origins of Consumer Confidence
Authors: De Boef Suzanna , Kellstedt Paul M.
Published: September 2004

Economic conditions, the story usually goes, influence consumer confidence, which in turn influences both political evaluations and votes. But we have little sense of the origins of consumer confidence itself. It is generally assumed that monthly reports of the nation's level of consumer confidence respond to objective economic conditions. We argue that politics is important for understanding consumer sentiment beyond what we know from economic conditions. Specifically, we demonstrate a direct effect of political evaluations of the president's management of the economy, the party of the president, extraordinary political events, and monetary policy, as well as an indirect effect of media coverage of the economy, on consumer sentiment, after controlling for economic conditions. When news coverage is positive, citizens give favorable evaluations, leading to more positive sentiment. Our findings suggest that understanding the political economy requires an emphasis on the causal effect of politics as well as economics.
Avoidance or Engagement? Issue Convergence in U.S. Presidential Campaigns, 1960–2000
Authors: Sigelman Lee , Buell Emmett H.
Published: September 2004

A widely noted and oft‐decried characteristic of campaigns in the United States is the tendency of the competing sides to talk past each other—to avoid engaging with one another on the same issues. We bring a massive database on statements by the major‐party presidential candidates and other campaign spokespersons in the 1960 through 2000 elections to bear on the question of issue convergence. Far from the exception, a high degree of similarity in the issue emphases of the two sides appears to have been the norm in these campaigns. This result suggests the need to rethink some influential empirical, formal, and normative perspectives on campaigns.
Economic Insecurity and the Globalization of Production
Authors: Scheve Kenneth , Slaughter Matthew J.
Published: September 2004

A central question in the international and comparative political economy literatures on globalization is whether economic integration increases worker insecurity in advanced economies. Previous research has focused on the role of international trade and has failed to produce convincing evidence that such a link exists. In this article, we argue that globalization increases worker insecurity, but that foreign direct investment (FDI) by multinational enterprises (MNEs) is the key aspect of integration generating risk. FDI by MNEs increases firms' elasticity of demand for labor. More‐elastic labor demands, in turn, raise the volatility of wages and employment, all of which tends to make workers feel less secure. We present new empirical evidence, based on the analysis of panel data from Great Britain collected from 1991 to 1999, that FDI activity in the industries in which individuals work is positively correlated with individual perceptions of economic insecurity. This correlation holds in analyses accounting for individual‐specific effects and a wide variety of control variables.
The Conditional Nature of Presidential Responsiveness to Public Opinion
Authors: Canes‐Wrone Brandice , Shotts Kenneth W.
Published: September 2004

How does public opinion affect presidential policymaking? We address this issue by testing a diverse set of hypotheses with data concerning a set of individual policies across time. In particular, the data revolve around presidential budgetary proposals on a set of major policy issues for which there are recurring surveys on citizens' preferences over spending. The analysis suggests that presidents are more responsive to mass opinion on issues that are familiar to citizens in their everyday lives. Also, for reelection‐seeking presidents, responsiveness is shown to depend upon two key political factors. First, presidents are more responsive to public opinion when the next election is imminent. Second, the effect of presidential popularity is nonmonotonic; presidents with average approval ratings are most likely to adopt policy positions congruent with public opinion, whereas presidents with approval ratings that are significantly above or below average have the greatest propensity to take unpopular positions.
Campaign Advertising and Democratic Citizenship
Authors: Freedman Paul , Franz Michael , Goldstein Kenneth
Published: September 2004

Concern about the state of American democracy is a staple of political science and popular commentary. Critics warn that levels of citizen participation and political knowledge are disturbingly low and that seemingly ubiquitous political advertising is contributing to the problem. We argue that political advertising is rife with both informational and emotional content and actually contributes to a more informed, more engaged, and more participatory citizenry. With detailed advertising data from the 2000 election, we show that exposure to campaign advertising produces citizens who are more interested in the election, have more to say about the candidates, are more familiar with who is running, and ultimately are more likely to vote. Importantly, these effects are concentrated among those citizens who need it most: those with the lowest pre‐existing levels of political information.
Where's the Pivot? Obstruction and Lawmaking in the Pre‐cloture Senate
Authors: Wawro Gregory J. , Schickler Eric
Published: September 2004

This article employs a three‐pronged approach to test competing theories regarding the size of coalitions required for passing legislation prior to the adoption of cloture in the Senate. We compare predictions generated by a model derived from the theory of pivotal politics with those generated by the theory of universalism. To test these predictions, we first examine coalition sizes on the passage of significant legislation. Second, we analyze the size of coalitions on dilatory motions as a predictor of success in defeating legislation. Finally, we examine coalition sizes on tariff legislation to assess the degree to which politics in this policy area were majoritarian. We find that a pivotal politics‐based model incorporating the median voter and veto pivot generally outperforms universalism in explaining lawmaking patterns in the pre‐cloture Senate. Narrow majorities were quite successful at legislating, although minority obstruction fostered uncertainty about the threshold required to force a final vote when adjournment loomed.
How Initiators End Their Wars: The Duration of Warfare and the Terms of Peace
Authors: Slantchev Branislav L.
Published: September 2004

The new theories of endogenous war termination generally predict that initiators would tend to do badly the longer the war, that information acquired during the war would outweigh information available prior to its outbreak, that stronger initiators would be slower to update their estimates about the outcome, and that uncertainty would increase the expected duration of conflict. This article subjects these hypotheses to statistical testing by estimating time‐accelerated log‐logistic hazard models of duration and bootstrapped ordered probit models of outcome with a new data set of 104 interstate wars from 1816 to 1991. The Monte Carlo simulation results support the hypotheses and the substantive findings provide ample reason for continuing with this research agenda.
Risk Analysis for Invasive Species: General Framework and Research Needs
Authors: Andersen Mark C. , Adams Heather , Hope Bruce , Powell Mark
Published: September 2004

A joint workshop was convened by the Society for Risk Analysis Ecological Risk Assessment Specialty Group and the Ecological Society of America Theoretical Ecology Section to provide independent scientific input into the formulation of methods and processes for risk assessment of invasive species. In breakout sessions on (1) the effects of invasive species on human health, (2) effects on plants and animals, (3) risk analysis issues and research needs related to entry and establishment of invasive species, and (4) risk analysis issues and research needs related to the spread and impacts of invasive species, workshop participants discussed an overall approach to risk assessment for invasive species. Workshop participants agreed on the need for empirical research on areas in which data are lacking, including potential invasive species, native species and habitats that may be impacted by invasive species, important biological processes and phenomena such as dispersal, and pathways of entry and spread for invasive species. Participants agreed that theoretical ecology can inform the process of risk assessment for invasive species by providing guidelines and conceptual models, and can contribute to improved decision making by providing a firm biological basis for risk assessments.
The Impact of Dietary Changes Among the Inuit of Nunavik (Canada): A Socioeconomic Assessment of Possible Public Health Recommendations Dealing with Food Contamination
Authors: Duhaime Gérard , Chabot Marcelle , Fréchette Pierre , Robichaud Véronique , Proulx Solange
Published: September 2004

Inuit populations meet a large portion of their food needs by eating country food in which pollutants are concentrated. Despite the fact that they contain pollutants, the consumption of country food has many health, social, economic, and cultural benefits. A risk determination process was set up in order to help regional health authorities of Nunavik to deal with this particular issue. Based on Nunavik health authorities' objectives to encourage the region's inhabitants to change their dietary habits, and on both the risks and the benefits of eating country food, several management options were developed. The options aimed at reducing exposure to contaminants by either substituting certain foods with others that have a lower contaminant content or by store‐bought foods. This article aims at assessing the potential economic impact of these risk management options before being implemented. Relevant economic data (aggregate income and monetary outlays for the purchase of food and equipment required for food production by households) were collected and identified to serve as a backdrop for the various replacement scenarios. Results show that household budgets, and the regional economy, are not significantly affected by the replacement of contaminated foods with the purchase of store‐bought meat, and even less so if the solution involves replacing contaminated foods with other types of game hunted in the region. When financial support is provided by the state, the households can even gain some monetary benefits. Results show that public health authorities' recommended changes to dietary habits among the Inuit of Nunavik would not necessarily involve economic constraints for Inuit households.
Sensory CIDP presenting as cryptogenic sensory polyneuropathy
Authors: Chin Russell L. , Latov Norman , Sander Howard W. , Hays Arthur P. , Croul Sidney E. , Magda Paul , Brannagan Thomas H.
Published: September 2004

Abstract  The objective of this study was to report that patients with chronic inflammatory demyelinating polyneuropathy (CIDP) can present with a clinical picture of cryptogenic sensory neuropathy. Patients with distal sensory neuropathy and electrodiagnostic studies that are minimally abnormal or consistent with an axonal pathology are usually diagnosed as having cryptogenic sensory neuropathy if no cause for neuropathy can be found. Some of these patients, however, may have sensory CIDP. We reviewed the records of eight patients with CIDP, diagnosed by sural nerve biopsy, who presented with sensory neuropathy and electrodiagnostic studies that were minimally abnormal or revealed changes consistent with axonal neuropathy. All patients reported distal numbness and paresthesias and, on examination, had predominantly large fiber distal sensory loss and normal muscle strength. In most patients, deep tendon reflexes were reduced or absent. Sural nerve biopsies in all patients were consistent with chronic myelinopathy, with quantitative teased fiber analysis revealing segmental remyelination in 13–40% of the fibers. The four patients who received IVIg therapy had improved sensation and gait. Of the remaining four patients, one is being followed, one had spontaneous remission, one was lost to follow‐up, and one, with contraindications to therapy, reported disease progression. Sensory CIDP may present as cryptogenic sensory polyneuropathy with normal or axonal electrophysiologic features. Sural nerve biopsy should be considered in patients with progressive, predominantly large fiber sensory neuropathy of otherwise unknown etiology, as they may have sensory CIDP that responds to therapy.
Motor nerve damage is associated with anti‐ganglioside antibodies in diabetes
Authors: Matà Sabrina , Betti Elisabetta , Masotti Giulio , Pinto Francesco , Lolli Francesco
Published: September 2004

Abstract  Few reports exist on the association between the humoral immune response to glycolipids and neuropathic findings in diabetes. To address this issue, we assayed serum anti‐GM1, GD1b, GD1a, and sulfatides IgG and IgM in a group of 85 non‐selected diabetic patients, and correlated these antibodies to clinical and electrophysiological findings. Diabetic patients had higher mean titers of anti‐GM1 (IgM), GD1b, GD1a, and sulfatide (IgG) antibodies when compared to healthy controls. Patients with a positive titer of anti‐ganglioside antibodies had significant alterations of motor conduction parameters. The statistical significance increased when considering those patients with both anti‐ganglioside reactivity and a high value for glycosylated hemoglobin. Production of antibodies to ganglioside may follow the exposure of hidden motor nerve epitopes in damaged motor nerves and contribute to the neuropathy.
Macrophage appearance in the epineurium and endoneurium of dorsal root ganglion exposed to nucleus pulposus
Authors: Murata Yasuaki , Rydevik Björn , Takahashi Kazuhisa , Takahashi Ichiro , Olmarker Kjell
Published: September 2004

Abstract  Recently, it was observed that local application of nucleus pulposus may induce a characteristic reaction at the surface of the dorsal root ganglion (DRG). This change was inflammatory in nature and occurred as early as 1 day after the application of nucleus pulposus. Herniation of the nucleus pulposus was surgically induced in the L4‐5 disc in rats. The L4 DRGs were resected 3, 24, and 72 h after surgery and sectioned. The sections were processed for immunohistochemistry using antisera to the macrophage marker ED1 and observed using light microscopy. The appearance of macrophages was confirmed 3, 24, and 72 h after the surgery. Macrophages were mainly distributed in the epineurial space of the DRG 3 h after disc incision and also in the endoneurial tissue 24 and 72 h after disc incision. The immunoreactivity was significantly stronger at 24 and 72 h than at 3 h in the parts of the DRG without apparent changes in the disc incision series (p < 0.01). Within the epineurium adjacent to application of nucleus pulposus, the number was significantly higher at 3 h than at 24 and 72 h (p < 0.05). We conclude that experimental disc herniation with leakage of nucleus pulposus results in macrophage recruitment to the epineurium of the DRG 3 h after disc incision and to the endoneurium 24 and 72 h after disc incision.
Inhibitor development in patients receiving recombinant factor VIII (Recombinate rAHF/Bioclate®): a prospective pharmacovigilance study
Authors: Ewenstein B. M. , Gomperts E. D. , Pearson S. , O'Banion M. E.
Published: September 2004

Summary.  Clinical trials to date have not been adequately powered to assess comparatively infrequent events such as inhibitor development in previously treated patients (PTPs). Comprehensive large‐scale pharmacovigilance studies can be useful for this purpose. We prospectively collected inhibitor development reports worldwide among recipients of Recombinate rAHF recombinant factor VIII (rFVIII), also formerly distributed under the product name Bioclate®, for the entire postlicensure period from 1993 through 2002. To determine level of exposure to rFVIII we also compiled the Recombinate rAHF/Bioclate International Units (IU) distributed annually. To estimate inhibitor incidence separately for previously untreated or minimally treated patients (PUPs) with 1–50 exposure days and PTPs with >50 exposure days, we used haemophilia A incidence and prevalence data and pooled mean annual rFVIII consumption per PUP and PTP from international multicentre prospective clinical trials. Documented inhibitor cases totalled 89, and the total quantity of Recombinate rAHF/Bioclate rFVIII distributed was 6.48 ×109 IU. No lot association or other clustering of inhibitor events was evident in PTPs. The incidence of all reported inhibitors, expressed as a percentage of patients treated, was 11.9% (CI: 5.05–28.0%) for PUPs when compared with 0.123% (CI: 0.030–0.512%) for PTPs. The rates for high‐titre inhibitors (>5 BU) only were 5.96% (CI: 3.00–11.8%) for PUPs and 0.0554% (CI: 0.0113–0.271%) for PTPs. Thus, incidence rates for both all inhibitors and high‐titre inhibitors in PTPs were 1% of the corresponding rates in PUPs. Data from prospective PUP clinical trials involving intensive active monitoring suggest that true inhibitor incidence may be approximately twice that estimated in this pharmacovigilance study. Nevertheless, inhibitor development in PTPs receiving Recombinate rAHF/Bioclate is infrequent.
Successful use of ReFacto continuous infusion in two paediatric patients with severe haemophilia A undergoing orthopaedic surgery
Authors: Sennett M. M. , De Alarcón P. A.
Published: September 2004

Summary.  In this report we describe the successful use of B‐domain‐deleted recombinant factor VIII (ReFacto) administered by continuous infusion during orthopaedic procedures in two children with severe haemophilia A. Both patients underwent ankle synovectomy and in patient 2, a medial patello‐femoral ligament repair was performed in the same operative session. Patient 2 developed septic arthritis A in his knee joint and arthroscopic joint irrigation and debridement was performed 2 weeks after the initial procedure. Surgical cover was initiated with a bolus dose of ReFacto 50 IU kg−1 followed by continuous infusion at 3.3–4.8 IU kg−1 h−1 which was maintained for up to 9 days postoperatively. Patient 2 received an additional bolus dose of 15 IU kg−1 during the infusion period. All procedures were performed without haemostatic complications and long‐term orthopaedic outcomes were good in both patients.
Informativeness of linkage analysis for genetic diagnosis of haemophilia A in India
Authors: Jayandharan G. , Shaji R. V. , George B. , Chandy M. , Srivastava A.
Published: September 2004

Summary.  The objective of this study was to assess the frequency of factor VIII (FVIII) gene intron 1 and intron 22 inversions and the informativeness of polymorphic markers for the genetic diagnosis of patients with haemophilia A (HA). Fifty unrelated patients with HA were first assessed for the intron 1 and intron 22 inversion mutations. Inversion‐negative families were then screened for the bi‐allelic intragenic markers – intron 7 G→A polymorphism, HindIII site in intron 19 and XbaI site in intron 22 and the multiallelic dinucleotide CA repeat alleles in introns 13 and 22. The extragenic, multiallelic VNTR DXS52 (st14) was also analysed. Intron 22 inversion mutation was found in 38% (n = 19) of all patients and 46% of those with severe HA. Intron 1 inversion was found in one (2%) patient. Of the 30 inversion‐negative families, XbaI site polymorphism was the single most informative marker (70%, n = 21/30) followed by HindIII (60%, n = 18/30), intron 13 CA repeats (56.66%, n = 17/30), intron 22 CA repeats (50%, n = 15/30), DXS52 VNTR (23.33%, n = 7/30) and intron 7 G→A polymorphism (6.66%, n = 2/30). The combined use of these markers was informative in 92% (n = 46/50) of HA families. Based on the informativeness of these markers a comprehensive algorithm has been proposed for genetic diagnosis of HA in India.
Shoulder hemiarthroplasty to manage haemophilic arthropathy: two case studies
Authors: Dalzell R.
Published: September 2004

Summary.  Bleeds within the shoulder joint can lead to significant joint destruction and may have associated pain, decreased range of movement (ROM), and impaired function. Conservative management should involve prompt administration of Factor VIII and physiotherapy to address all surrounding structures so as to minimize further damage. If conservative management fails to relieve severe, unremitting shoulder pain in the presence of underlying arthropathy, then arthroplasty may be considered. Outcomes of arthroplasties performed for osteoarthritis and rheumatoid arthritis appear favourable. Few articles, however, have addressed shoulder arthroplasty to manage haemophilic arthropathy, and no reports have documented the rehabilitation process. Three hemiarthroplasties were performed at the Royal Brisbane and Women's Hospital on two men with haemophilia. There were no surgical or postoperative complications. Rehabilitation included intensive physiotherapy. The results in each case revealed a decrease in pain, and an increase in ROM and function postoperatively. These findings suggest that hemiarthroplasty with postoperative physiotherapy may be a feasible option to manage severe, chronic and progressing shoulder pain as a result of haemophilic arthropathy of the shoulder.