bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaporation from a waste-rock surface, Key Lake, Saskatchewan
Authors: Carey S K , Barbour S L , Hendry M J
Published: September 2005

An accurate evaluation of the water balance and net percolation through mine waste-rock piles is critical to the development of decommissioning plans for these wastes. One of the most difficult components of the water balance to quantify is evaporation. Evaporation and the surface energy balance were directly measured from a fine- to medium-grained sand waste-rock pile near Key Lake, Saskatchewan, Canada between 6 June and 25 August 2002 using the eddy covariance method. Actual evaporation for the 81 day study period was 145 mm, which was significantly less than both a potential evaporation of 247 mm and rainfall of 236 mm during this period. The waste-rock pile had a distinct radiation and energy balance as high surface albedo reduced available energy for evaporation. The greatest fraction of daytime available energy was partitioned into latent heat, followed by soil heat flux, and sensible heat flux, respectively. The Bowen ratio averaged 0.45 ± 0.10 for the entire study period. A simple actual evapotranspiration model, which is an extension of Penman and consistent with the complementary approach, was used to simulate evaporation atop the pile. Model results indicate 134 mm of evaporation for the study period and agree well with observations.Key words: evaporation, waste-rock, energy balance, eddy covariance, acid rock drainage.
Soil improvement for a storage yard using the combined vacuum and fill preloading method
Authors: Yan S.-W , Chu J
Published: September 2005

This paper presents a case study of using the combined vacuum and fill surcharge preloading method to improve the foundation soil for a storage yard at Tianjin Port, China. A vacuum load of 80 kPa was applied for 4-8 weeks before fill surcharge was added in stages. The site to be improved was recently reclaimed using dredged clay slurry. Both the consolidated clay slurry fill and the seabed soils were very soft. After the combined vacuum and fill surcharge preloading, the ground settled more than 1 m. The average degree of consolidation achieved was more than 80%. The undrained shear strength of the soil increased twofold. The water content of the soil also decreased substantially. The soil improvement procedure using the combined vacuum and fill surcharge preloading method and the instrumentation scheme are described, the field monitoring data are presented and analyzed, and methods to estimate the degree of consolidation and several other issues related to the combined preloading method are discussed.Key words: case history, consolidation, ground improvement.
Evaluating the hydraulic conductivity at three different scales within an unconfined sand aquifer at Lachenaie, Quebec
Authors: Chapuis Robert P , Dallaire Véronique , Marcotte Denis , Chouteau Michel , Acevedo Nelson , Gagnon Francis
Published: September 2005

This paper presents the evaluation of scale effects for the hydraulic conductivity, k, of a sand. Data were obtained using several methods at a site that was densely instrumented with piezometers within an area of about 100 m × 100 m. The 3.13.6 m thick sand deposit rests on a thick, nonfissured Champlain Sea clay deposit. At the small scale, local k values were obtained from the grain-size curves of sand samples and also from ground-penetrating radar surveys. At the intermediate scale, k values were obtained from field variable-head tests using piezometers. At the large scale, k values were obtained from pumping-test drawdowns in steady-state conditions. In this sand aquifer, the careful evaluations at three scales gave similar narrow distributions for the hydraulic conductivity, and therefore no scale effect is evidenced.Key words: hydraulic conductivity, sand, scale effect, gradation, monitoring well, pumping.
Timing of breeding and reproductive performance of female European rabbits in response to winter temperature and body mass
Authors: Rödel Heiko G , Bora Agnes , Kaetzke Paul , Khaschei Martin , Hutzelmeyer Hans Dieter , Zapka Manuela , von Holst Dietrich
Published: September 2005

Environmental conditions frequently affect the reproduction of many mammal and bird species by modulating maternal body condition. In our long-term study of European rabbits, Oryctolagus cuniculus (L., 1758), we investigated the effects of winter weather conditions and body mass on reproductive performance and reproductive timing. Specifically, we tested whether winter temperature affects both reproductive timing and reproductive performance of female rabbits or whether females compensate for low body mass after winter by a shift in the timing of the onset of breeding. Winter body mass loss was higher in years with lower winter temperatures, and the onset of breeding was delayed after these conditions. However, mean size and mass of the first litter of each season and seasonal fecundity were not reduced after harsh winters. At the individual level, females with lower winter body mass started to reproduce later, but we did not find any effects on litter size and mass. In contrast, breeding body mass was a strong predictor of the females' reproductive performance. We also found high between-year variation in mean body mass in late winter but not in mean breeding body mass. In conclusion, our results suggest that the negative effects of winter weather on the body mass of females, which should potentially affect their reproductive performance, were compensated for by delaying the onset of breeding.
Larval density and the Charnov–Bull model of adaptive environmental sex determination in a copepod
Authors: Voordouw Maarten J , Robinson H Eve , Stebbins Gabe , Albert Arianne Y.K , Anholt Bradley R
Published: September 2005

Charnov and Bull suggested that environmentally induced variation in adult body size coupled with sex-specific differences in fitness can select for the evolution of adaptive environmental sex determination (ESD). In this study we determine whether larval density affects sex determination in the copepod Tigriopus californicus (Baker, 1912), as predicted by Charnov and Bull. Individuals reared at low densities developed faster and were significantly larger than siblings reared at high densities. For these laboratory-reared individuals, sexual selection on male body size was stronger than fecundity selection on female body size, but this sex-specific pattern of selection was reversed in the field. Differences in food availability (for females) and the mode of competition (for males) may account for the conflicting results between laboratory and field. We found a weak effect of larval density on sex determination in a pilot experiment but no effect in a second, more powerful experiment. While larval density did not affect the sex ratio of T. californicus, our sex-specific estimates of selection on adult body size will inform future models of adaptive ESD in this species and other copepods.
A test of the genetic compatibility hypothesis with tree swallows,Tachycineta bicolor
Authors: Barber Colleen A , Edwards Mandy J , Robertson Raleigh J
Published: September 2005

The genetic compatibility hypothesis proposes that females should mate with genetically dissimilar males whose alleles best complement their own, resulting in greater offspring heterozygosity. It predicts that genetic similarity between social pairs will be positively related to the proportion of extra-pair young within broods and negatively related to hatching success. We tested these two predictions in tree swallow (Tachycineta bicolor (Vieillot, 1808)) pairs (n = 72). Tree swallows have one of the highest rates of extra-pair paternity among socially monogamous passerines. Contrary to expectation, genetic similarity of a social pair, as measured by the band-sharing coefficient (estimated from multilocus DNA fingerprints), tended to be negatively related to the proportion of extra-pair young within broods, but failed to predict hatching success. When including only the subset of nests for which we had complete genotyping data (n = 37), we again found a significant negative relationship between genetic similarity and the proportion of extra-pair young within broods. Genetic similarity did not differ significantly between nests with and without extra-pair young, nor did it differ between nests with total versus partial hatching success. Overall, our data do not support the genetic compatibility hypothesis in tree swallows, and in fact show some evidence against it.
SYSTEMATIC DERIVATION OF TREE CONTRACTION ALGORITHMS
Authors: MATSUZAKI KIMINORI , HU ZHENJIANG , KAKEHI KAZUHIKO , TAKEICHI MASATO
Published: September 2005

While tree contraction algorithms play an important role in efficient tree computation in parallel, it is difficult to develop such algorithms due to the strict conditions imposed on contracting operators. In this paper, we propose a systematic method of deriving efficient tree contraction algorithms from recursive functions on trees. We identify a general recursive form that can be parallelized into efficient tree contraction algorithms, and present a derivation strategy for transforming general recursive functions to the parallelizable form. We illustrate our approach by deriving a novel parallel algorithm for the maximum connected-set sum problem on arbitrary trees, the tree-version of the well-known maximum segment sum problem.
A FINITE CAPACITY RESEQUENCING MODEL WITH MARKOVIAN ARRIVALS
Authors: CHAKRAVARTHY SRINIVAS R. , CHUKOVA STEFANKA
Published: September 2005

In this paper, we consider a two-server finite capacity queuing model in which messages should leave the system in the order in which they entered the system. Messages arrive according to a Markovian arrival process (MAP) and any message finding the buffer full is considered lost. Out-of-sequence messages are stored in a (finite) buffer and may lead to blocking when a processed message cannot be placed in the buffer. The steady state analysis of the model is performed by exploiting the structure of the coefficient matrices. The departure process is characterized and two interesting optimization problems along with illustrative numerical examples are discussed.
MULTI-ITEM DETERMINISTIC FUZZY INVENTORY MODEL
Authors: YADAVALLI V. S. S. , JEEVA M. , RAJAGOPALAN RAJALAKSHMI
Published: September 2005

In this note, a fuzzy inventory model with multiple items is considered. Economic order quantities (EOQs) are developed for these items. The costs involved in inventory are always assumed to be exact, otherwise called as crisp or hard, but in practice these costs are not exact or precise but vary over a range. In such cases an application of fuzzy set theory plays a vital role in obtaining the EOQ. An application of this model to manpower planning is studied with an example; sensitivity analysis is also made.
PERFORMANCE ANALYSIS ON A COMPLEX REMANUFACTURING SYSTEM
Authors: HOU YUMEI , ZHANG HANQIN
Published: September 2005

This paper focuses on the performance analysis on a complex remanufacturing system that consists of a disassembling shop, a remanufacturing shop, an assembling shop, and a warehouse. The optimal remanufacturing policy is given. Furthermore, by the matrix-geometric method, the immediate demand fill rate is established.
TOOLS FOR THE SIMULATION OF HARD HADRONIC COLLISIONS
Authors: Mangano Michelangelo L. , Stelzer Timothy J.
Published: September 2005

▪ Abstract  This review gives a pedagogical introduction to the current status and ongoing progress in the development of QCD-based Monte Carlo tools for the calculation and simulation of high-Q2 processes in hadronic collisions.
Are tyrosine kinases involved in mediating contraction-stimulated muscle glucose transport?
Authors: Wright David C. , Geiger Paige C. , Han Dong-Ho , Holloszy John O.
Published: September 2005

Muscle contractions and insulin stimulate glucose transport into muscle by separate pathways. The contraction-mediated increase in glucose transport is mediated by two mechanisms, one involves the activation of 5′-AMP-activated protein kinase (AMPK) and the other involves the activation of calcium/calmodulin-dependent protein kinase II (CAMKII). The steps leading from the activation of AMPK and CAMKII to the translocation of GLUT4 to the cell surface have not been identified. Studies with the use of the tyrosine kinase inhibitor genistein suggest that one or more tyrosine kinases could be involved in contraction-stimulated glucose transport. The purpose of the present study was to determine the involvement of tyrosine kinases in contraction-stimulated glucose transport in rat soleus and epitrochlearis muscles. Contraction-stimulated glucose transport was completely prevented by pretreatment with genistein (100 μM) and the related compound butein (100 μM). However, the structurally distinct tyrosine kinase inhibitors 4-amino-5-(4-chlorophenyl)-7-( t-butyl)pyrazolo[3,4-d]pyridine and herbimycin did not reduce contraction-stimulated glucose transport. Furthermore, genistein and butein inhibited glucose transport even when muscles were exposed to these compounds after being stimulated to contract. Muscle contractions did not result in increases in tyrosine phosphorylation of proteins such as proline-rich tyrosine kinase and SRC. These results provide evidence that tyrosine kinases do not mediate contraction-stimulated glucose transport and that the inhibitory effects of genistein on glucose transport result from direct inhibition of the glucose transporters at the cell surface.
Accumulation of nonesterified fatty acids causes the sustained energetic deficit in kidney proximal tubules after hypoxia-reoxygenation
Authors: Feldkamp Thorsten , Kribben Andreas , Roeser Nancy F. , Senter Ruth A. , Weinberg Joel M.
Published: September 2005

Kidney proximal tubules exhibit decreased ATP and reduced, but not absent, mitochondrial membrane potential (Δψm) during reoxygenation after severe hypoxia. This energetic deficit, which plays a pivotal role in overall cellular recovery, cannot be explained by loss of mitochondrial membrane integrity, decreased electron transport, or compromised F1F0-ATPase and adenine nucleotide translocase activities. Addition of oleate to permeabilized tubules produced concentration-dependent decreases of Δψmmeasured by safranin O uptake (threshold for oleate = 0.25 μM, 1.6 nmol/mg protein; maximal effect = 4 μM, 26 nmol/mg) that were reversed by delipidated BSA (dBSA). Cell nonesterified fatty acid (NEFA) levels increased from <1 to 17.4 nmol/mg protein during 60- min hypoxia and remained elevated at 7.6 nmol/mg after 60 min reoxygenation, at which time ATP had recovered to only 10% of control values. Safranin O uptake in reoxygenated tubules, which was decreased 85% after 60-min hypoxia, was normalized by dBSA, which improved ATP synthesis as well. dBSA also almost completely normalized Δψmwhen the duration of hypoxia was increased to 120 min. In intact tubules, the protective substrate combination of α-ketoglutarate + malate (α-KG/MAL) increased ATP three- to fourfold, limited NEFA accumulation during hypoxia by 50%, and lowered NEFA during reoxygenation. Notably, dBSA also improved ATP recovery when added to intact tubules during reoxygenation and was additive to the effect of α-KG/MAL. We conclude that NEFA overload is the primary cause of energetic failure of reoxygenated proximal tubules and lowering NEFA substantially contributes to the benefit from supplementation with α-KG/MAL.
Experimental membranous nephropathy redux
Authors: Cybulsky Andrey V. , Quigg Richard J. , Salant David J.
Published: September 2005

Membranous nephropathy (MN) is a common cause of nephrotic syndrome in adults. Active and passive Heymann nephritis (HN) in rats are valuable experimental models because their features so closely resemble human MN. In HN, subepithelial immune deposits form in situ as a result of circulating antibodies. Complement activation leads to assembly of C5b-9 on glomerular epithelial cell (GEC) plasma membranes and is essential for sublethal GEC injury and the onset of proteinuria. This review revisits HN and focuses on areas of substantial progress in recent years. The response of the GEC to sublethal C5b-9 attack is not simply due to disruption of the plasma membrane but is due to the activation of specific signaling pathways. These include activation of protein kinases, phospholipases, cyclooxygenases, transcription factors, growth factors, NADPH oxidase, stress proteins, proteinases, and others. Ultimately, these signals impact on cell metabolic pathways and the structure/function of lipids and key proteins in the cytoskeleton and slit-diaphragm. Some signals affect GEC adversely. Thus C5b-9 induces partial dissolution of the actin cytoskeleton. There is a decline in nephrin expression, reduction in F-actin-bound nephrin, and loss of slit-diaphragm integrity. Other signals, such as endoplasmic reticulum stress, may limit complement-induced injury, or promote recovery. The extent of complement activation and GEC injury is dependent, in part, on complement-regulatory proteins, which act at early or late steps within the complement cascade. Identification of key steps in complement activation, the cellular signaling pathways, and the targets will facilitate therapeutic intervention in reversing GEC injury in human MN.
Has Armstrong's cycle efficiency improved?
Authors: Martin David T. , Quod Marc J. , Gore Christopher J.
Published: September 2005

This case describes the physiological maturation from ages 21 to 28 yr of the bicyclist who has now become the six-time consecutive Grand Champion of the Tour de France, at ages 27–32 yr. Maximal oxygen uptake (V̇o2max) in the trained state remained at ∼6 l/min, lean body weight remained at ∼70 kg, and maximal heart rate declined from 207 to 200 beats/min. Blood lactate threshold was typical of competitive cyclists in that it occurred at 76–85% V̇o2max, yet maximal blood lactate concentration was remarkably low in the trained state. It appears that an 8% improvement in muscular efficiency and thus power production when cycling at a given oxygen uptake (V̇o2) is the characteristic that improved most as this athlete matured from ages 21 to 28 yr. It is noteworthy that at age 25 yr, this champion developed advanced cancer, requiring surgeries and chemotherapy. During the months leading up to each of his Tour de France victories, he reduced body weight and body fat by 4–7 kg (i.e., ∼7%). Therefore, over the 7-yr period, an improvement in muscular efficiency and reduced body fat contributed equally to a remarkable 18% improvement in his steady-state power per kilogram body weight when cycling at a given V̇o2 (e.g., 5 l/min). It is hypothesized that the improved muscular efficiency probably reflects changes in muscle myosin type stimulated from years of training intensely for 3–6 h on most days.
Brachial artery FMD with 5-minute distal cuff occlusion—a useful pathophysiological test after all!
Authors: Celermajer David S.
Published: September 2005

This letter is in response to the Point:Counterpoint series “Flow-mediated dilation does/does not reflect nitric oxide-mediated endothelial function” that appeared in the September issue (vol. 99: 1233–1238, 2005; doi:10.1152/japplphysiol.00601.2005; http://jap.physiology.org/content/vol99/issue3/2005 ).
Flow-mediated vasodilation partially reflects nitric oxide-mediated endothelial function
Authors: Linke Axel , Erbs Sandra , Hambrecht Rainer
Published: September 2005

This letter is in response to the Point:Counterpoint series “Flow-mediated dilation does/does not reflect nitric oxide-mediated endothelial function” that appeared in the September issue (vol. 99: 1233–1238, 2005; doi:10.1152/japplphysiol.00601.2005; http://jap.physiology.org/content/vol99/issue3/2005 ).
Flow-mediated dilation and biological variability
Authors: Thomas Gail D.
Published: September 2005

This letter is in response to the Point:Counterpoint series “Flow-mediated dilation does/does not reflect nitric oxide-mediated endothelial function” that appeared in the September issue (vol. 99: 1233–1238, 2005; doi:10.1152/japplphysiol.00601.2005; http://jap.physiology.org/content/vol99/issue3/2005 ).
Flow-mediated dilation
Authors: Parker Beth A. , Proctor David N.
Published: September 2005

This letter is in response to the Point:Counterpoint series “Flow-mediated dilation does/does not reflect nitric oxide-mediated endothelial function” that appeared in the September issue (vol. 99: 1233–1238, 2005; doi:10.1152/japplphysiol.00601.2005; http://jap.physiology.org/content/vol99/issue3/2005 ).
In FMD, NO is actually “the middle man”
Authors: Wray D. Walter , Richardson Russell S.
Published: September 2005

This letter is in response to the Point:Counterpoint series “Flow-mediated dilation does/does not reflect nitric oxide-mediated endothelial function” that appeared in the September issue (vol. 99: 1233–1238, 2005; doi:10.1152/japplphysiol.00601.2005; http://jap.physiology.org/content/vol99/issue3/2005 ).
Statistical Assessment of Time-Varying Dependency Between Two Neurons
Authors: Ventura Valérie , Cai Can , Kass Robert E.
Published: September 2005

The joint peristimulus time histogram (JPSTH) provides a visual representation of the dynamics of correlated activity for a pair of neurons. There are many ways to adjust the JPSTH for the time-varying firing-rate modulation of each neuron, and then to define a suitable measure of time-varying correlated activity. Our approach is to introduce a statistical model for the time-varying joint spiking activity so that the joint firing rate can be estimated more efficiently. We have applied an adaptive smoothing method, which has been shown to be effective in capturing sudden changes in firing rate, to the ratio of joint firing probability to the probability of firing predicted by independence. A bootstrap procedure, applicable to both Poisson and non-Poisson data, was used to define a statistical significance test of whether a large ratio could be attributable to chance alone. A numerical simulation showed that the bootstrap-based significance test has very nearly the correct rejection probability, and can have markedly better power to detect departures from independence than does an approach based on testing contiguous bins in the JPSTH. In a companion paper, we show how this formulation can accommodate latency and time-varying excitability effects, which can confound spike timing effects.
Dynamic-Clamp Analysis of the Effects of Convergence on Spike Timing. II. Few Synaptic Inputs
Authors: Xu-Friedman Matthew A. , Regehr Wade G.
Published: September 2005

Sensory pathways in the nervous system possess mechanisms for decreasing spike-timing variability (“jitter”), probably to increase acuity. Most studies of jitter reduction have focused on convergence of many subthreshold inputs. However, many neurons receive only a few active inputs at any given time, and jitter reduction under these conditions is not well understood. We examined this issue using dynamic-clamp recordings in slices from mouse auditory brain stem. Significant jitter reduction was possible with as few as two inputs, provided the inputs had several features. First, jitter reduction was greatest and most reliable for supra-threshold inputs. Second, significant jitter reduction occurred when the distribution of input times had a rapid onset, i.e., for alpha- but not for Gaussian-distributed inputs. Third, jitter reduction was compromised unless late inputs were suppressed by the refractory period of the cell. These results contrast with the finding in the previous paper in which many subthreshold inputs contribute to jitter reduction, whether alpha- or Gaussian-distributed. In addition, convergence of many subthreshold inputs could fail to elicit any postsynaptic response when the input distribution outlasted the refractory period of the cell. These significant differences indicate that each means of reducing jitter has advantages and disadvantages and may be more effective for different neurons depending on the properties of their inputs.
A Stroock formula for a certain class of Lévy processes and applications to finance
Authors: Eddahbi M. , Solé J. L. , Vives J.
Published: September 2005

We find a Stroock formula in the setting of generalized chaos expansion introduced by Nualart and Schoutens for a certain class of Lévy processes, using a Malliavin‐type derivative based on the chaotic approach. As applications, we get the chaotic decomposition of the local time of a simple Lévy process as well as the chaotic expansion of the price of a financial asset and of the price of a European call option. We also study the behavior of the tracking error in the discrete delta neutral hedging under both the equivalent martingale measure and the historical probability.
On the first‐passage time of integrated Brownian motion
Authors: Hesse Christian H.
Published: September 2005

Let (Bt; t ≥ 0) be a Brownian motion process starting from B0 = ν and define . For a ≥ 0, set τa,ν : = inf{t : Xν(t) = a} (with inf φ = ∞). We study the conditional moments of τa,ν given τa,ν < ∞. Using martingale methods, stopping‐time arguments, as well as the method of dominant balance, we obtain, in particular, an asymptotic expansion for the conditional mean E(τa,ν | τa,ν < ∞) as ν → ∞. Through a series of simulations, it is shown that a truncation of this expansion after the first few terms provides an accurate approximation to the unknown true conditional mean even for small ν.
Asymptotic expansion for the functional of Markovian evolution in Rd in the circuit of diffusion approximation
Authors: Samoilenko I. V.
Published: September 2005

We study the asymptotic expansion for solution of singularly perturbed equation for functional of Markovian evolution in Rd. The view of regular and singular parts of solution is found.
ℬ𝒞‐total stability and almost periodicity for some partial functional differential equations with infinite delay
Authors: Elazzouzi Abdelhai , Ezzinbi Khalil
Published: September 2005

In this paper, we study the existence of an almost periodic solution for some partial functional differential equation with infinite delay. We assume that the linear part is nondensely defined and satisfies the known Hille‐Yosida condition. We prove if the null solution of the homogeneous equation is ℬ𝒞‐total stable, then the nonhomogeneous equation has an almost periodic solution.
Abstract stochastic integrodifferential delay equations
Authors: Keck David N. , McKibben Mark A.
Published: September 2005

We investigate a class of abstract stochastic integrodifferential delay equations dependent upon a family of probability measures in a separable Hilbert space. We establish the existence and uniqueness of a mild solution, along with various continuous dependence estimates and Markov (weak and strong) properties of this solution. This is followed by a convergence result concerning the strong solutions of the Yosida approximations of our equation, from which we deduce the weak convergence of the measures induced by these strong solutions to the measure induced by the mild solution of the primary problem under investigation. Next, we establish the pth moment and almost sure exponential stability of the mild solution. Finally, an analysis of two examples, namely a generalized stochastic heat equation and a Sobolev‐type evolution equation, is provided to illustrate the applicability of the general theory.
Local volatility in the Heston model: a Malliavin calculus approach
Authors: Ewald Christian-Oliver
Published: September 2005

We implement the Heston stochastic volatility model by using multidimensional Ornstein‐Uhlenbeck processes and a special Girsanov transformation, and consider the Malliavin calculus of this model. We derive explicit formulas for the Malliavin derivatives of the Heston volatility and the log‐price, and give a formula for the local volatility which is approachable by Monte‐Carlo methods.
Properties of fixed point set of a multivalued map
Authors: Khan Abdul Rahim
Published: September 2005

Properties of the set of fixed points of some discontinuous multivalued maps in a strictly convex Banach space are studied; in particular, affirmative answers are provided to the questions related to set of fixed points and posed by Ko in 1972 and Xu and Beg in 1998. A result regarding the existence of best approximation is derived.
Existence of solutions of general nonlinear fuzzy Volterra‐Fredholm integral equations
Authors: Balachandran K. , Kanagarajan K.
Published: September 2005

We study the problem of existence and uniqueness of solutions of a class of nonlinear fuzzy Volterra‐Fredholm integral equations.
Recursive smoothers for hidden discrete‐time Markov chains
Authors: Aggoun Lakhdar
Published: September 2005

We consider a discrete‐time Markov chain observed through another Markov chain. The proposed model extends models discussed by Elliott et al. (1995). We propose improved recursive formulae to update smoothed estimates of processes related to the model. These recursive estimates are used to update the parameter of the model via the expectation maximization (EM) algorithm.
Complete analysis of MAP/G/1/N queue with single (multiple) vacation(s) under limited service discipline
Authors: Gupta U. C. , Banik A. D. , Pathak S. S.
Published: September 2005

We consider a finite‐buffer single‐server queue with Markovian arrival process (MAP) where the server serves a limited number of customers, and when the limit is reached it goes on vacation. Both single‐ and multiple‐vacation policies are analyzed and the queue length distributions at various epochs, such as pre‐arrival, arbitrary, departure, have been obtained. The effect of certain model parameters on some important performance measures, like probability of loss, mean queue lengths, mean waiting time, is discussed. The model can be applied in computer communication and networking, for example, performance analysis of token passing ring of LAN and SVC (switched virtual connection) of ATM.
Problems of interaction of vibrating surfaces withprocessable materials
Authors: Ostapenko V. A.
Published: September 2005

We consider the mathematical model of interaction of a vibrating surface with
the load placed on it. With the purpose of accounting for
influence on behavior of not only system interaction of a blade
with a load but also internal interaction of particles of a
material, the load is submitted as a finite number of strips with
zero thickness. The carrying blade is represented as a vibrating
membrane. It is supposed that the weight of the material is
comparable to or considerably surpasses the weight of the blade.
Therefore, the model takes into account the inertia of the
material. In the model with joint movement of the blade and the
load, the separation opportunity of the load from the blade is
provided. Therefore, there is a phase of separate movement of the
blade and the load, with their subsequent connection accompanied
with impact. The process of system movement is represented as
alternating sequences of joint and separate movements of the load
and the blade. The modeling of the process of the interaction of
the load and the blade is represented as an initial‐boundary value
problem. The method of solution is developed and the exact
solution of the set problem is obtained in a class of generalized
functions.
Dynamic stability of functionally graded plate underin‐plane compression
Authors: Tylikowski Andrzej
Published: September 2005

Functionally graded materials have gained considerable attention
in the high‐temperature applications. A study of parametric
vibrations of functionally graded plates subjected to in‐plane
time‐dependent forces is presented. Moderately large deflection
equations taking into account a coupling of in‐plane and
transverse motions are used. Material properties are graded in the
thickness direction of the plate according to volume fraction
power law distribution. An oscillating temperature causes
generation of in‐plane time‐dependent forces destabilizing the
plane state of the plate equilibrium. The asymptotic stability and
almost‐sure asymptotic stability criteria involving a damping
coefficient and loading parameters are derived using Liapunov′s
direct method. Effects of power law exponent on the stability
domains are studied.
Novel procedure to compute a contact zone magnitude ofvibrations of two‐layered uncoupled plates
Authors: Awrejcewicz J. , Krysko V. A. , Ovsiannikova O.
Published: September 2005

A novel iteration procedure for dynamical problems, where in each
time step, a contacting plates′ zone is improved, is proposed.
Therefore, a zone and magnitude of a contact load are
also improved. Investigations of boundary conditions′ influence on
externally driven vibrations of uncoupled two‐layer plates, where
for each of the layers, the Kirchhoff hypothesis holds, are
carried out.
Maximal monotone model with delay term of convolution
Authors: Lamarque Claude-Henri , Bastien Jérôme , Holland Matthieu
Published: September 2005

Mechanical models are governed either by partial differential equations with boundary conditions and initial conditions (e.g., in the frame of continuum mechanics) or by ordinary differential equations (e.g., after discretization via Galerkin procedure or directly from the model description) with the initial conditions. In order to study dynamical behavior of mechanical systems with a finite number of degrees of freedom including nonsmooth terms (e.g., friction), we consider here problems governed by differential inclusions. To describe effects of particular constitutive laws, we add a delay term. In contrast to previous papers, we introduce delay via a Volterra kernel. We provide existence and uniqueness results by using an Euler implicit numerical scheme; then convergence with its order is established. A few numerical examples are given.
Realization problem for positive linear systems with time delay
Authors: Kaczorek Tadeusz
Published: September 2005

The realization problem for positive single‐input single‐output
discrete‐time systems with one time
delay is formulated and solved. Necessary and sufficient
conditions for the solvability of the realization problem are
established. A procedure for computation of a minimal positive
realization of a proper rational function is presented and
illustrated by an example.
On the optimal control of affine nonlinear systems
Authors: Popescu M. , Dumitrache A.
Published: September 2005

The minimization control problem of quadratic functionals for the
class of affine nonlinear systems with the hypothesis of nilpotent
associated Lie algebra is analyzed. The optimal control
corresponding to the first‐, second‐, and third‐order nilpotent
operators is determined. In this paper, we have considered the
minimum fuel problem for the multi‐input nilpotent control and for
a scalar input bilinear system for such systems. For the
multi‐input system, usually an analytic closed‐form solution for
the optimal control is not possible and it is
necessary to use numerical integration for the set of m
nonlinear coupled second‐order differential equations. The optimal
control of bilinear systems is obtained by considering the Lie
algebra generated by the system matrices. It should be noted that
we have obtained an open‐loop control depending on the initial
value of the state x0.
Epidemiology of Hepatitis C Virus in Korea
Authors: Shin Hai-Rim
Published: September 2005

Mortality due to liver cancer in Korea ranks as one of the highest in the world. Both hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are high-risk factors for liver cancer. Although HBV is by far the more important risk factor for the development of hepatocellular carcinoma (HCC) in Korea, HCV infection is more closely associated with HCC in elderly patients. Therefore, the evaluation of risk factors for HCV infection, including blood transfusion, is important. This study reviews the literature on HCV prevalence and risk factors among the general population, as well as the distribution of HCV genotypes in Korea. An overall estimate of the prevalence of anti-HCV among Koreans older than 40 years was 1.29% (95% confidence interval 1.12–1.48) during 1995–2000. Blood transfusion was the strongest risk factor for transmission of HCV infection. Risk factors for HCV infection in Korea other than blood transfusion and history of acupuncture have not been proven. The most prevalent HCV genotype is 1b followed by 2a. Even though the prevalence of anti-HCV in Korea has been reduced and the risk of HCV transmission through blood transfusion has markedly decreased, public-health programs to prevent de novo infections should be developed. Moreover, most people infected with HCV in Korea are older than 40 years, and therefore, the surveillance of adults (≧40 years) for HCV infection will be helpful in early detection of HCC developing in them.
Fructose Feeding Increases Insulin Resistance but Not Blood Pressure in Sprague-Dawley Rats
Authors: D’Angelo Gerard , Elmarakby Ahmed A. , Pollock David M. , Stepp David W.
Published: September 2005

Fructose feeding has been widely reported to cause hypertension in rats, as assessed indirectly by tail cuff plethysmography. Because there are potentially significant drawbacks associated with plethysmography, we determined whether blood pressure changes could be detected by long-term monitoring with telemetry in age-matched male Sprague-Dawley rats fed either a normal or high-fructose diet for 8 weeks. Fasting plasma glucose (171±10 versus 120±10 mg/dL), plasma insulin (1.8±0.5 versus 0.7±0.1 μg/L), and plasma triglycerides (39±2 versus 30±2 mg/dL) were modestly but significantly elevated in fructose-fed animals. Using the hyperinsulinemic euglycemic clamp technique, the rate of glucose infusion necessary to maintain equivalent plasma glucose was significantly reduced in fructose-fed compared with control animals (22.9±3.6 versus 41.5±2.9 mg/kg per minute;
P
<0.05). However, mean arterial pressure (24-hour) did not change in the fructose-fed animals over the 8-week period (111±1 versus 114±2 mm Hg; week 0 versus 8), nor was it different from that in control animals (109±2 mm Hg). Conversely, systolic blood pressure measured by tail cuff plethysmography at the end of the 8-week period was significantly greater in fructose-fed versus control animals (162±5 versus 139±1 mm Hg;
P
<0.001). Together, these data demonstrate that long-term fructose feeding induces mild insulin resistance but does not elevate blood pressure. We propose that previous reports of fructose-induced hypertension reflect a heightened stress response by fructose-fed rats associated with restraint and tail cuff inflation.
Perturbation Growth in Baroclinic Waves
Authors: Stevens Martha R. , Hakim Gregory J.
Published: September 2005

Floquet theory is applied to the stability of time-periodic, nonparallel shear flows consisting of a baroclinic jet plus a neutral wave. This configuration is chosen as an idealized representation of baroclinic waves in a storm track, and the stability analysis may be helpful for understanding generic properties of the growth of forecast errors in such regions. Two useful attributes of Floquet theory relevant to this problem are that the period-average mode growth rate is norm independent, and the t→ ∞ stability limit is determined by the stability over one period. Exponentially growing Floquet modes are found for arbitrarily small departures from parallel flows.

Approximately 70% of Floquet-mode growth in energy is due to barotropic conversion, with the remainder due to zonal heat flux. Floquet-mode growth rates increase linearly with neutral wave amplitude (i.e., the “waviness” of the jet) and also increase with neutral wave wavelength. Growth rates for meridionally localized jets are approximately 40% smaller than for comparable cases with linear vertical shear (the Eady jet). Singular vectors for these flows converge to the leading Floquet mode over one basic-state period, and the leading instantaneous optimal mode closely resembles the leading Floquet mode.

Initial-value problems demonstrate that the periodic basic states are absolutely unstable, with Floquet modes spreading faster than the basic-state flow both upstream and downstream of an initially localized disturbance. This behavior dominates the convective instability of parallel-flow jets when the neutral baroclinic wave amplitude exceeds a threshold value of about 8–10 K. This result suggests that forecast errors in a storm track may spread faster, and affect upstream locations, for sufficiently wavy jets.
Trend Analysis for Atmospheric Hydrocarbon Partitioning Using Continuous Thermodynamics
Authors: Harstad K.
Published: September 2005

The partitioning of atmospheric hydrocarbons into vapor and condensed phases when the species count is large is considered using the formalism of continuous thermodynamics. The vapor saturation pressures and condensate species distribution are parameterized using the species normal boiling temperatures. Qualitative trends in activity coefficient values and phase equilibrium behavior that are relevant to the outer planets and Titan are discussed in terms of a much simplified perspective on these aspects of partitioning. The trends found are generally consistent with those from other published atmospheric model results.
Age at First Sexual Assault and Current Substance Use and Depression
Authors: Kaukinen Catherine , DeMaris Alfred
Published: September 2005

This article explores how the association between sexual violence and substance use and mental health differs by race and life course stage. Analyses are based on data (n = 8,000) from the Violence and Threats of Violence against Women and Men in the United States Survey, 1994-1996 (NVAWS). Although sexual violence does not heighten the risk of problem drinking for White women, minority women victimized in adulthood are significantly more likely to engage in problem drinking and use illicit drugs. This suggests that for minority women the effects of recent victimization experiences result in immediate and potentially long-lasting consequences. The findings with respect to the association between sexual violence and depression are consistent with the child and adolescent development literature. It is Hispanic women who are more likely to suffer depression as a consequence of child sexual assault.
Managing Data for the New Global Workforce
Authors: Tichman Bonnie
Published: September 2005

More organizations are entering the global marketplace and are now faced with managing a global workforce. Confronted with the disparate HR systems and processes typically used across international offices, it can be hard for companies to pull together even the most basic information about employees. This prevents them from leveraging their global workforce, a powerful strategic business asset. Two of the keys to solving this problem are data consolidation and the adoption of processes that will allow organizations to make the best use of this data while delivering HR services effectively and efficiently. Conceptually, these steps may seem simple, but many organizations find that implementing the technologies and structures to meet these goals on a global scale can quickly become complicated. As a result, companies are turning to business process outsourcing to provide the tools and expertise needed. This in turn allows the HR department to manage more strategic processes and become a partner to other parts of the organization, developing workforce strategies that align with corporate strategies to move the business forward.
The Test of Strategic Culture: Germany, Pacifism and Pre-emptive Strikes
Authors: Dalgaard-Nielsen Anja
Published: September 2005

Germany was the first country to issue a categorical refusal to support the US-led war in Iraq. Some have interpreted this as the result of a clash between the strategic cultures of Germany and the USA, others as a sign that a more nationalistic and assertive Germany is emerging. This article explains the apparently contradictory aspects of Germany’s stance on Iraq by identifying two competing strands within Germany’s strategic culture. It concludes that the German refusal signals neither a reversion to a pacifist stance nor that Germany is in a process of shedding the bonds and alliances that have so far framed the reunified Germany’s military policy. Iraq simply showed that Germany, like most other countries, has conditions that have to be met - in Germany’s case, conditions flowing from the coexistence of two competing schools of thought within Germany’s strategic culture.
Peyer patches are not required for acute graft-versus-host disease after myeloablative conditioning and murine allogeneic bone marrow transplantation
Authors: Welniak Lisbeth A. , Kuprash Dmitry V. , Tumanov Alexei V. , Panoskaltsis-Mortari Angela , Blazar Bruce R. , Sun Kai , Nedospasov Sergei A. , Murphy William J.
Published: September 2005

Graft-versus-host disease (GVHD) is a multistep disease process following allogeneic bone marrow transplantation (BMT). It has been postulated that the induction of acute GVHD requires the presence of Peyer patches (PPs). A new tumor necrosis factor (TNF)–deficient strain has been developed that totally lacks PPs and displays the defects characteristic of TNF ablation but not lymphotoxin-associated defects characterized by lack of both PPs and lymph nodes. To determine the necessity of PPs in acute lethal GVHD induction, we transplanted full major histocompatibility complex (MHC)–mismatched grafts into myeloablated TNF knockout recipients. No differences in the survival or GVHD-associated histopathologic lesions were observed between the recipients. We conclude that neither PPs nor host TNF-α is required for the development of acute lethal GVHD in mice that undergo myeloablative conditioning and allogeneic BMT.
Association analysis of a highly polymorphic CAG Repeat in the human potassium channel gene KCNN3 and migraine susceptibility
Authors: Curtain Robert , Sundholm James , Lea Rod , Ovcaric Mick , MacMillan John , Griffiths Lyn
Published: September 2005

Background

Migraine is a polygenic multifactorial disease, possessing environmental and genetic causative factors with multiple involved genes. Mutations in various ion channel genes are responsible for a number of neurological disorders.KCNN3is a neuronal small conductance calcium-activated potassium channel gene that contains two polyglutamine tracts, encoded by polymorphic CAG repeats in the gene. This gene plays a critical role in determining the firing pattern of neurons and acts to regulate intracellular calcium channels.

Methods

The present association study tested whether length variations in the second (more 3') polymorphic CAG repeat in exon 1 of theKCNN3gene, are involved in susceptibility to migraine with and without aura (MA and MO). In total 423 DNA samples from unrelated individuals, of which 202 consisted of migraine patients and 221 non-migraine controls, were genotyped and analysed using a fluorescence labelled primer set on an ABI310 Genetic Analyzer. Allele frequencies were calculated from observed genotype counts for theKCNN3polymorphism. Analysis was performed using standard contingency table analysis, incorporating the chi-squared test of independence and CLUMP analysis.

Results

Overall, there was no convincing evidence thatKCNN3CAG lengths differ between Caucasian migraineurs and controls, with no significant difference in the allelic length distribution of CAG repeats between the population groups (P= 0.090). Also the MA and MO subtypes did not differ significantly between control allelic distributions (P> 0.05). The prevalence of the long CAG repeat (>19 repeats) did not reach statistical significance in migraineurs (P= 0.15), nor was there a significant difference between the MA and MO subgroups observed compared to controls (P= 0.46 andP= 0.09, respectively), or between MA vs MO (P= 0.40).

Conclusion

This association study provides no evidence that length variations of the second polyglutamine array in the N-terminus of theKCNN3channel exert an effect in the pathogenesis of migraine.