bluuebunny/crossref_metadata_2025 huggingface dataset:
The U.S. Property and Liability Insurance Industry: Firm Growth, Size, and Age
Authors: Choi Byeongyong Paul
Published: March 2010

Abstract

The relationship between firm size, age, and growth is tested for the U.S. property and liability (P‐L) insurance industry, and the determinants of firm characteristics on firm growth are analyzed. Using Heckman's two‐stage methodology, this article examines the relationship between corporate growth and firm size. The relationship between firm growth and firm age is also investigated. Furthermore, to determine time‐varying effects, the analysis is conducted for the different subperiods. The results of this article strongly support Gibrat's Law in the U.S. P‐L insurance market for the testing periods. The results are consistent for longer time periods and for shorter subperiods. It also finds that young firms grow faster than old firms during the sample periods. Related to the determinants of firm characteristics on firm growth, insurers using less input cost tend to grow fast. Economies of scope are positively related to firm growth as well.
A Game‐Theoretical Interpretation of Guaranteed Renewability in Health Insurance
Authors: Abdus Salam
Published: March 2010

Abstract

A game‐theoretical model is developed here that can explain why the premiums of the health insurance contracts in the individual health insurance market do not vary that much over time, even in absence of any legal restriction on premiums. In this model the insurer and the individuals interact for an infinite number of periods, and the threats of punishments in case of deviations force both the insurer and the individuals to stay on a constant premium path. This model, unlike the other models of guaranteed renewability, does not presume commitment of the insurer.
Feature Article: A Resource‐Based Perspective on Business Strategies of Newly Founded Subsidiaries: The Case of German Pensionsfonds
Authors: Berry‐Stölzle Thomas R. , Altuntas Muhammed
Published: March 2010

Abstract

Diversification by firms into unfamiliar areas of business is achieved either by acquisition of an existing business in the destination industry or a greenfield start‐up. This article focuses on the business strategy of greenfield start‐ups. We theorize and find that firms entering a market by establishing a new subsidiary rely solely on their own preexisting internal resources, making it favorable to align the business strategy of the start‐up with the firm's value‐generating competencies. Our empirical results, which are based on a sample of German Pensionsfonds and their parent companies, are consistent with the view that the business strategy choice of a newly founded subsidiary is substantially directed by the internal resources and competencies of the parent firm.
Educational Insights: A Hybrid Course in Risk Management and Insurance
Authors: Carson James , Cole Cassandra R. , Gatzlaff Kevin , Maroney Patrick F. , McCullough Kathleen A.
Published: March 2010

Abstract

Universities and colleges continue to face constraints related to classroom space and faculty time, thus increasing the need to consider options such as hybrid courses that can leverage available resources. This article discusses the benefits of a hybrid course, as well as its design and implementation at a large, public university. In addition, for universities that use the introduction to risk and insurance course as a significant course for attracting majors, we identify the benefits for students from the use of hybrid courses, such as the variety of materials and activities utilized, as well as the flexibility in scheduling. This information may be useful in marketing the course so that it will be immediately attractive to students.
Fabrication of High‐Purity Ti3SiC2Powders by an In Situ Reaction of Polycarbosilane and Metal Titanium
Authors: Yang Jinshan , Dong Shaoming , Ding Yusheng , Wang Zhen , Zhou Haijun , Lu Bo
Published: March 2010

High‐purity titanium silicon carbide powders were fabricated by anin situreaction of polycarbosilane and metal titanium. The effects of the starting reagents and the pyrolysis temperature on the fabrication of high‐purity Ti3SiC2were studied. The results showed that high‐purity Ti3SiC2could be obtained when the atomic ratio of Ti:Si was 3:1.5 and the effect of the temperature of pyrolysis on the purity of the powders was insignificant. The atomic ratio of Ti:Si was calculated on the basis of the empirical formula of SiC2.5H7.
Pyrochlore‐Free Pb(Ni1/3Nb2/3)O3–PbTiO3 Ceramics with Superior Piezoelectric Properties Synthesized Using an Optimized Polyethylene Glycol‐Assisted Solid‐State Reaction
Authors: Ye Yin , Huang Haitao , Zhou Limin , Wang Song , Yu Shuhui
Published: March 2010

By introducing polyethylene glycol (PEG) into the raw oxide powders during ball milling, 0.64Pb(Ni1/3Nb2/3)O3–0.36PbTiO3 (0.64PNN–0.36PT) powers, and ceramics with pure perovskite phase have been successfully synthesized. The effect of PEG on the formation of the perovskite phase was examined by varying the amount of PEG200 (40, 60, and 80 wt%) and using PEG with different molecular weight (Mw) during the ball‐milling process. It was determined that interactions between PEG and PbO favor the formation of the desired perovskite phase. The dielectric constant and piezoelectric coefficient in samples prepared with 60 wt% PEG200 were found to be greatly enhanced as compared with that of samples synthesized by the conventional solid‐state reaction method. The room temperature dielectric constant and the maximum dielectric constant (at Tm=90°C) reached 5950 and 33 680, respectively, at a measuring frequency of 1 kHz. The piezoelectric constant d33 reached an exceptionally high value of 570 pC/N. It was determined that PEG with a low Mw was more effective in the formation of the perovskite phase than those with a high Mw.
Spark Plasma Sintering of Ultrafine TiCxN1−x Powders Synthesized by a Mechanically Induced Self‐Sustaining Reaction
Authors: Borrell Amparo , Fernández Adolfo , Torrecillas Ramón , Córdoba José M. , Avilés Miguel A. , Gotor Francisco J.
Published: March 2010

High‐purity, nanometer‐sized titanium carbonitride powders, TiCxN1−x, were obtained with a mechanically induced self‐sustaining reaction (MSR) in a high‐energy planetary ball mill from a mixture of titanium and different carbon precursors under a nitrogen atmosphere. A promising method for developing dense TiCxN1−x materials is the coupling of MSR with the spark plasma sintering (SPS) technique. The powders were sintered at different temperatures to provide a completely dense monolithic ceramic (>99% theoretical density). In this work, the influence of the carbon precursor and SPS treatment on the material microstructures were studied, and the main mechanical properties of the end material were evaluated.
The prognostic value of intraepithelial and stromal CD3‐, CD117‐ and CD138‐positive cells in non‐small cell lung carcinoma
Authors: AL‐SHIBLI KHALID , AL‐SAAD SAMER , ANDERSEN SIGVE , DONNEM TOM , BREMNES ROY M. , BUSUND LILL‐TOVE
Published: March 2010

Al‐Shibli K, Al‐Saad S, Andersen S, Donnem T, Bremnes RM, Busund L‐T. The prognostic value of intraepithelial and stromal CD3‐, CD117‐ and CD138‐positive cells in non‐small cell lung carcinoma. APMIS 2010; 118: 371–82.

The major value of prognostic markers in potentially curable non‐small cell lung carcinoma (NSCLC) should be to guide therapy after surgical treatment. Although tumor‐infiltrating T lymphocytes and plasma cells have been documented in NSCLC, a clear association with clinical outcome, especially for the stromal component, has not been well established. The aim of this study was to elucidate the prognostic significance of these cells/markers in the epithelial and stromal compartments of NSCLC. Tissue microarrays from 335 resected, stage I‐IIIA, NSCLC were constructed by duplicate cores from viable neoplastic epithelial and stromal areas. Immunohistochemistry was used to evaluate the infiltration of CD3+, CD117+ as well as CD138+ cells in epithelial and stromal areas. In univariate analyses, increasing numbers of stromal CD3+ (p = 0.001) and epithelial CD3+ cells (p = 0.004) correlated significantly with an improved disease‐specific survival. No such relation was noted with CD3+ or CD117+ cells. In the multivariate analysis, stromal CD3+ cells was an independent prognostic factor for disease‐specific survival (HR 1.925, CI 1.21–3.04, p = 0.005). Increased presence of the pan T‐cell marker, CD3, which is an independent factor, correlates with improved clinical outcome in NSCLC. This prognostic impact of T cells is clearer in the tumor stroma. Neither plasma cells nor mast cells were prognostic indicators in our cohort.
REVIEW ARTICLE: Tolerance to the Foetal Allograft?
Authors: Chaouat Gérard , Petitbarat Marie , Dubanchet Sylvie , Rahmati Mona , Ledée Nathalie
Published: March 2010

Citation Chaouat G, Petitbarat M, Dubanchet S, Rahmati M, Ledée N. Tolerance to the Foetal Allograft? Am J Reprod Immunol 2010

In this review, we will detail the concept of tolerance and its history in reproductive immunology. We will then consider whether it applies to the foetal–maternal relationship and discuss the mechanisms involved in non‐rejection of the foeto‐placental unit.
REVIEW ARTICLE: Immunological Modes of Pregnancy Loss
Authors: Kwak‐Kim Joanne , Park Joon Cheol , Ahn Hyun Kyong , Kim Joon Woo , Gilman‐Sachs Alice
Published: March 2010

Citation Kwak‐Kim J, Park JC, Ahn HK, Kim JW, Gilman‐Sachs A. Immunological modes of pregnancy loss. Am J Reprod Immunol 2010

During the implantation period, a significant portion of embryos are lost and eventually less than half of clinically established pregnancies end as full‐term pregnancies without obstetrical complications. A significant portion of these pregnancy losses is associated with immune etiologies, including autoimmune and cellular immune abnormalities. Although an autoimmune etiology such as anti‐phospholipid antibodies (APAs) has been reported to induce placental infarct and thrombosis at maternal–fetal interface, APAs induce inflammatory immune responses as well. Inflammatory immune responses, such as increased proportions of NK cells and Th1/Th2 cell ratios in peripheral blood are related to recurrent pregnancy losses and multiple implantation failures. Systemic and local inflammatory immune responses seem to be induced by activation of Toll‐like receptors with infectious agents, fetal cell debris, or gonadotropin‐releasing hormone agonist, etc. Cellular activation of T and NK cells leads to pro‐inflammatory cytokine storm and consequently, placental infarction and thrombosis. Potential application of anti‐inflammatory therapeutic agents for the prevention of pregnancy losses should be explored further.
Large conformational changes in the Escherichia coli tryptophan synthase β2 subunit upon pyridoxal 5′‐phosphate binding
Authors: Nishio Kazuya , Ogasahara Kyoko , Morimoto Yukio , Tsukihara Tomitake , Lee Soo Jae , Yutani Katsuhide
Published: March 2010

To understand the basis for the lower activity of the tryptophan synthase β2 subunit in comparison to the α2β2 complex, we determined the crystal structures of apo‐β2 and holo‐β2 from Escherichia coli at 3.0 and 2.9 Å resolutions, respectively. To our knowledge, this is the first report of both β2 subunit structures with and without pyridoxal‐5′‐phosphate. The apo‐type molecule retained a dimeric form in solution, as in the case of the holo‐β2 subunit. The subunit structures of both the apo‐β2 and the holo‐β2 forms consisted of two domains, namely the N domain and the C domain. Although there were significant structural differences between the apo‐ and holo‐structures, they could be easily superimposed with a 22° rigid body rotation of the C domain. The pyridoxal‐5′‐phosphate‐bound holo‐form had multiple interactions between the two domains and a long loop (residues 260–310), which were missing in the apo‐form. Comparison of the structures of holo‐Ecβ2 and Stβ2 in the α2β2 complex from Salmonella typhimurium (Stα2β2) identified the cause of the lower enzymatic activity of holo‐Ecβ2 in comparison with Stα2β2. The substrate (indole) gate residues, Tyr279 and Phe280, block entry of the substrate into the β2 subunit, although the indole can directly access the active site as a result of a wider cleft between the N and C domains in the holo‐Ecβ2 subunit. In addition, the structure around βAsp305 of the holo‐Ecβ2 subunit was similar to the open state of Stα2β2 with low activity, resulting in lower activity of holo‐Ecβ2.

Structured digital abstract

MINT‐7712009: Ecβ2 (uniprotkb:P0A879) and Ecβ2 (uniprotkb:P0A879) bind (MI:0407) by x‐ray crystallography (MI:0114)

MINT‐7712032: Ecβ2 (uniprotkb:P0A879) and Ecβ2 (uniprotkb:P0A879) bind (MI:0407) by biophysical (MI:0013)
Ground-based detection of thermal emission from the exoplanet WASP-19b
Authors: Gibson N. P. , Aigrain S. , Pollacco D. L. , Barros S. C. C. , Hebb L. , Hrudková M. , Simpson E. K. , Skillen I. , West R.
Published: March 2010

We present an occultation of the newly discovered hot Jupiter system WASP-19, observed with the High Acuity Wide-field K-band Imager instrument on the VLT, in order to measure thermal emission from the planet's dayside at ∼2μm. The light curve was analysed using a Markov Chain Monte Carlo method to find the eclipse depth and the central transit time. The transit depth was found to be 0.366 ± 0.072 per cent, corresponding to a brightness temperature of 2540 ± 180 K. This is significantly higher than the calculated (zero-albedo) equilibrium temperature and indicates that the planet shows poor redistribution of heat to the night side, consistent with models of highly irradiated planets. Further observations are needed to confirm the existence of a temperature inversion and possibly molecular emission lines. The central eclipse time was found to be consistent with a circular orbit.
Large pulsar kicks from topological currents
Authors: Charbonneau James , Hoffman Kelsey , Heyl Jeremy
Published: March 2010

We show that kicks generated by topological currents may be responsible for the large velocities seen in a number of pulsars. The majority of the kicks builds up within the first second of the star's birth and generates a force about two orders of magnitude larger than a neutrino kick in the same temperature and magnetic field regime. Because of the nature of the topological currents, the star's cooling is not affected until it reaches 109 K; thereafter the current replaces neutrino emission as the dominant cooling process. A requirement for the kick to occur is a suitably thin crust on the star; this leads us to speculate that pulsars with large kicks are quark stars and those with small kicks are neutron stars. If true, this would be an elegant way to distinguish quark stars from neutron stars.
Venture Capital in Canada: Lessons for Building (or Restoring) National Wealth
Authors: Brenner Reuven , Brenner Gabrielle A.
Published: March 2010

Canadian policymakers and regulators have been praised for avoiding many of the policy blunders that, when combined with excessive risk‐taking by the banks, nearly brought down the U.S. financial sector. But, as the global economy begins to recover, policymakers everywhere need to find ways to stimulate the creation of new ventures.

On that score, Canada's record is not encouraging. The returns on Canadian venture capital investment have been dismally low, particularly in its government‐run funds. In a recent survey, 40% of U.S. venture capital partners identified Canada as having the least favorable treatment of investors of any country they had dealings with. And perhaps most troubling, half of the Canadian corporate executives responding to another survey cited “inability to retain talent” as the biggest threat to their firms.

The authors begin by suggesting that these findings are all related. Without investors and the know‐how and networks they bring with them, a country's ability to attract, develop, and retain top talent—business and managerial talent in particular—is significantly reduced. And as the authors go on to argue, the key to building a successful venture capital industry is to match talent with capital in such a way that all three parties—talent, capital providers, and the “matchmakers” who bring together talent and capital—are rewarded for superior performance and held accountable for failure.
Promotion Incentives and Corporate Performance: Is There a Bright Side to “Overpaying” the CEO?
Authors: Kale Jayant R. , Reis Ebru , Venkateswaran Anand
Published: March 2010

Earlier studies have shown that stronger equity‐based incentives for CEOs are generally associated with better corporate performance and higher values. In this article, the authors report the findings of their recent study of the effects of promotion‐based “tournament” incentives for non‐CEO executives (or “VPs”) on corporate performance for a large sample of companies during the 12‐year period from 1993‐2004.

The study's main finding is that such tournament incentives, as measured by the pay differential between the CEO and VPs, were associated with better corporate operating performance and higher corporate stock returns. Moreover, tournament incentives, as one would expect, appeared to be more effective when CEOs were nearing retirement—but less effective when the firm had a new CEO (and even weaker when the new CEO was an outsider).
The skill and style to model the evolution of resistance to pesticides and drugs
Authors:   REX Consortium
Published: March 2010

Resistance to pesticides and drugs led to the development of theoretical models aimed at identifying the main factors of resistance evolution and predicting the efficiency of resistance management strategies. We investigated the various ways in which the evolution of resistance has been modelled over the last three decades, by reviewing 187 articles published on models of the evolution of resistance to all major classes of pesticides and drugs. We found that (i) the technical properties of the model were most strongly influenced by the class of pesticide or drug and the target organism, (ii) the resistance management strategies studied were quite similar for the different classes of pesticides or drugs, except that the refuge strategy was mostly used in models of the evolution of resistance to insecticidal proteins, (iii) economic criteria were rarely used to evaluate the evolution of resistance and (iv) the influence of mutation, migration and drift on the speed of resistance development has been poorly investigated. We propose guidelines for the future development of theoretical models of the evolution of resistance. For instance, we stress the potential need to give more emphasis to the three evolutionary forces migration, mutation and genetic drift rather than simply selection.
When public‐sector salaries become public knowledge: Academic salaries and Ontario's Public Sector Salary Disclosure Act
Authors: Gomez Rafael , Wald Steven
Published: March 2010

Abstract:The effects of salary disclosure on public‐sector compensation have long been a source of controversy in political and academic circles. Some commentators suggest that because of political pressure and closer public scrutiny, salary disclosure is a good thing because it results in pay that is both lower than it would otherwise be and more sensitive to performance. On the other hand, disclosure raises serious privacy considerations and could also have an inflationary effect on salaries unless all elements in a causal chain linking public knowledge and lower pay are firmly in place. In this study, the authors examine the implications of Ontario's Public Sector Salary Disclosure Act with respect to university‐sector salaries. The main conclusions are that salary disclosure, in general, and in the academic sector in particular, has never fully accounted for proper comparability issues and has not been updated to reflect adjustments for inflation. The act also raises important questions of privacy that have not been fully addressed. Perhaps most notably, there is no evidence suggesting that salary disclosure has much of an influence in off‐setting other factors affecting salary growth.
Restructurer peu, restructurer mieux : leçons d'expériences ministérielles récentes au Canada
Authors: Bernier Luc , Gagnon Stéphanie
Published: March 2010

Sommaire:Dans cet article, nous nous intéressons aux restructurations de ministères fonctionnels. Nous revoyons d'abord les raisons recensées pour restructurer. Puis, nous comparons ce qui s'est passé récemment dans trois provinces du Canada ainsi qu'au gouvernement fédéral dans ce domaine. Les exemples utilisés nous informent sur les raisons de restructurer et sur les conséquences des restructurations. Les cas relatés, tous territoires confondus, nous amènent à constater que certains domaines semblent plus problématiques que d'autres (par ex. : développement économique, environnement), c'est‐à‐dire qu'ils font plus souvent l'objet de restructurations sans que la solution choisie ne soit satisfaisante par la suite. Les raisons évoquées pour expliquer les restructurations ont trait à la complexité du dossier et aux priorités gouvernementales. Par ailleurs, pour ce qui est des conséquences, elles sont de trois ordres : à savoir les conséquences administratives et budgétaires (coûts liés aux déménagements, à l'imprimerie, etc.), les conséquences relatives à l'orientation du ministère (sa mission et sa vision), et les incidences sur le personnel (pertes d'emploi, impact sur le moral des employés, etc.). Sur le plan pratique, les premiers ministres doivent particulièrement éviter de restructurer lors de remaniements ministériels.
Preserving environmental health and scientific credibility: a practical guide to reducing conflicts of interest
Authors: Rohr Jason R. , McCoy Krista A.
Published: March 2010

Conflicts of interest, situations where personal or organizational considerations have compromised or biased professional judgment and objectivity, can weaken scientific credibility, pose threats to biodiversity and ecosystem services, and are often precursors to corruption. Here, we review historical and international examples of conflicts of interest and their impacts on global biodiversity. We present a contemporary example of a conflict of interest that might have implications for the U.S. Environmental Protection Agency's re‐evaluation of the safety of the herbicide atrazine. To help scientists, natural resource managers, policy makers, and judicial officials identify and thwart conflicts of interest, we review strategies used by individuals and organizations with conflicts of interest to evade environmental and public health decisions, discuss the role of the scientific and governmental review processes in maintaining scientific integrity, and offer recommendations to reduce bias and facilitate sound and swift decision making for enhanced environmental health.
Expression of the RNA‐binding protein Musashi1 in adult liver stem‐like cells
Authors: Hattori Etsuko , Shu Hong‐Jin , Saito Takafumi , Okumoto Kazuo , Haga Hiroaki , Yokozawa Junji , Ito Junitsu , Watanabe Hisayoshi , Saito Koji , Togashi Hitoshi , Kawata Sumio
Published: March 2010

Aim:  Musashi1 is an RNA‐binding protein that regulates the Notch signaling pathway in stem cells. Our previous study revealed that Musashi1 is expressed in early hepatocytes during liver development in the mouse. However, whether this unique protein is expressed with Notch signaling markers in adult liver stem‐like cells remains unknown.

Methods:  Established hepatic stem‐like cells (HSLC), which were derived from adult Sprague–Dawley rats, were used for experiments in vitro. HSLC were differentiated into mature cells in terms of producing albumin when co‐cultured with epidermal growth factor (EGF). The mRNA expression of Musashi1, Notch family (Notch1 and Notch2), Jagged1 and Hes1 was examined in HSLC before and after cell differentiation using polymerase chain reaction‐based techniques. Protein expression of Musashi1 was examined in the HSLC and normal mature hepatocytes by immunofluorescence staining.

Results:  The mRNA expression of Musashi1, Notch1, Jagged1 and Hes1 was detected in the original HSLC before culturing with EGF but not in primary cultured mature hepatocytes. The mRNA expression of Musashi1 and Hes1 was found to be downregulated in differentiated HSLC that produce albumin. Protein expression of Musashi1 was detectable in the original HSLC but not in both differentiated HSLC and mature hepatocytes.

Conclusion:  These findings demonstrate that the RNA‐binding protein Musashi1 is expressed with Notch signaling markers in adult liver stem‐like cells.
Effect of Learning and Forgetting on Batch Sizes
Authors: Teyarachakul Sunantha , Chand Suresh , Ward James
Published: March 2010

This paper investigates the effect of learning and forgetting on production scheduling decisions. Numerous papers have appeared on this topic in the last four decades; they show that firms are better off producing in larger batches in the presence of learning and forgetting. However, these papers fail to consider one or more of realistic features of learning and forgetting; factors such as (1) the amount forgotten increases with break length between two batches and (2) the forgetting could be slow over an initial short interval followed by fast forgetting. Our paper contributes by demonstrating that a consideration of these realistic features leads to a different conclusion—firms may be better off producing in smaller batches in the presence of learning and forgetting. This is a new insight that provides one more justification for producing in small batches.
Effect of Upstream Rotor Vortical Disturbances on the Time-Averaged Performance of Axial Compressor Stators: Part 2—Rotor Tip Vortex/Streamwise Vortex–Stator Blade Interactions
Authors: Valkov T. V. , Tan C. S.
Published: March 2010

In a two-part paper, key computed results from a set of first-of-a-kind numerical simulations on the unsteady interaction of axial compressor stator with upstream rotor wakes and tip leakage vortices are employed to elucidate their impact on the time-averaged performance of the stator. Detailed interrogation of the computed flowfield showed that for both wakes and tip leakage vortices, the impact of these mechanisms can be described on the same physical basis. Specifically, there are two generic mechanisms with significant influence on performance: reversible recovery of the energy in the wakes/tip vortices (beneficial) and the associated nontransitional boundary layer response (detrimental). In the presence of flow unsteadiness associated with rotor wakes and tip vortices, the efficiency of the stator under consideration is higher than that obtained using a mixed-out steady flow approximation. The effects of tip vortices and wakes are of comparable importance. The impact of stator interaction with upstream wakes and vortices depends on the following parameters: axial spacing, loading, and the frequency of wake fluctuations in the rotor frame. At reduced spacing, this impact becomes significant. The most important aspect of the tip vortex is the relative velocity defect and the associated relative total pressure defect, which is perceived by the stator in the same manner as a wake. In Part 2, the focus will be on the interaction of stator with the moving upstream rotor tip and streamwise vortices, the controlling parametric trends, and implications on design.
External Heat Transfer Predictions in a Highly Loaded Transonic Linear Turbine Guide Vane Cascade Using an Upwind Biased Navier–Stokes Solver
Authors: Gehrer A. , Jericha H.
Published: March 2010

External heat transfer predictions are performed for two-dimensional turbine blade cascades. The Reynolds-averaged Navier–Stokes equations with algebraic (Arnone and Pacciani, 1998), one-equation (Spalart and Allmaras, 1994), and two-equation (low-Re k–ε, Biswas and Fukuyama, 1994) turbulence closures are solved with a fully implicit time-marching finite volume method. Comparisons with measurements (Arts et al., 1990; Arts, 1994) for a highly loaded transonic turbine nozzle guide vane cascade show good agreement in some cases, but also reveal problems with transition prediction and turbulence modeling. Special attention has been focused on the low-Re k–ε model concerning the influence of the inlet boundary condition for the ε-equation and problems in the stagnation point region.
Numerical Simulation of Impeller–Volute Interaction in Centrifugal Compressors
Authors: Hillewaert K. , Van den Braembussche R. A.
Published: March 2010

A numerical procedure to predict the impeller–volute interaction in a single-stage centrifugal compressor is presented. The method couples a three-dimensional unsteady flow calculation in the impeller with a three-dimensional time-averaged flow calculation in the volute through an iterative updating of the boundary conditions on the interface of both calculation domains. The method has been used to calculate the flow in a compressor with an external volute at off-design operation. Computed circumferential variations of flow angles, total temperature, and pressure are shown and compared with measurements. The good agreement between the predictions and measurements confirms the validity of the approach.
Improved Model for the Design and Analysis of Centrifugal Compressor Volutes
Authors: Van den Braembussche R. A. , Ayder E. , Hagelstein D. , Rautenberg M. , Keiper R.
Published: March 2010

This paper describes a new model for the analysis of the flow in volutes of centrifugal compressors. It explicitly takes into account the vortical structure of the flow that has been observed during detailed three-dimensional flow measurements. It makes use of an impeller and diffuser response model to predict the nonuniformity of the volute inlet flow due, to the circumferential variation of the pressure at the volute inlet, and is therefore applicable also at off-design operation of the volute. Predicted total pressure loss and static pressure rise coefficients at design and off-design operation have been compared with experimental data for different volute geometries but only one test case is presented here. Good agreement in terms of losses and pressure rise is observed at most operating points and confirms the validity of the impeller and diffuser response model.
Numerical Study of Blood Flow at the End-to-Side Anastomosis of a Left Ventricular Assist Device for Adult Patients
Authors: Yang Ning , Deutsch Steven , Paterson Eric G. , Manning Keefe B.
Published: March 2010

We use an implicit large eddy simulation (ILES) method based on a finite volume approach to capture the turbulence in the anastomoses of a left ventricular assist device (LVAD) to the aorta. The order-of-accuracy of the numerical schemes is computed using a two-dimensional decaying Taylor–Green vortex. The ILES method is carefully validated by comparing to documented results for a fully developed turbulent channel flow at Reτ=395. Two different anastomotic flows (proximal and distal) are simulated for 50% and 100% LVAD supports and the results are compared with a healthy aortic flow. All the analyses are based on a planar aortic model under steady inflow conditions for simplification. Our results reveal that the outflow cannulae induce high exit jet flows in the aorta, resulting in turbulent flow. The distal configuration causes more turbulence in the aorta than the proximal configuration. The turbulence, however, may not cause any hemolysis due to low Reynolds stresses and relatively large Kolmogorov length scales compared with red blood cells. The LVAD support causes an acute increase in flow splitting in the major branch vessels for both anastomotic configurations, although its long-term effect on the flow splitting remains unknown. A large increase in wall shear stress is found near the cannulation sites during the LVAD support. This work builds a foundation for more physiologically realistic simulations under pulsatile flow conditions.
Design, synthesis, and degradation studies of new enzymatically erodible Poly(hydroxyethyl methacrylate)/poly(ethylene oxide) hydrogels
Authors: Khelfallah Nawel S. , Decher Gero , Mésini Philippe J.
Published: March 2010

This work describes the synthesis and the study of poly(hydroxyethyl methacrylate) PHEMA hydrogels, cross-linked by poly(ethylene oxide)(PEO) chains containing the Gly-Gly-Leu tripeptide. This sequence was selected for its ability to be cleaved by subtilisin, a bacterial protease. The cross-linker was synthesized by coupling the peptide with two amino-terminated PEO chains of Mw=3400 g/mol. The resulting polymer was characterized by size exclusion chromatography, nuclear magnetic resonance, and mass spectroscopy, and was shown to be readily cleaved by subtilisin. Its esterification of the hydroxyl end groups into methacrylate afforded a macromonomer that was used as a degradable cross-linker and copolymerized with hydroxyethylmethacrylate to form hydrogels. The swelling ratio of the gels increases when the PEO cross-linker/polyHEMA ratio increases. Incubation of these gels with the enzyme led to the total degradation of the gels. These assays show that these gels can be used as drug-delivery systems where the release is triggered by the presence of proteases.
Combined microslit electrokinetic measurements and reflectometric interference spectroscopy to study protein adsorption processes
Authors: Zimmermanna Ralf , Osaki Toshihisa , Gauglitz Günter , Werner Carsten
Published: March 2010

Streaming potential/current measurements for the characterization of charge formation processes at solid/liquid interfaces were combined with reflectometric interference spectroscopy. The simultaneous determination of electrosurface characteristics and the optical thickness of interfacial layers provides information on structural variations of adsorbed or covalently bound polymers and on charge dependent adsorption and desorption phenomena at solid/liquid interfaces. To demonstrate the potentialities of this extended approach for biointerfacial studies the authors report a series of experiments on the adsorption of the plasma protein fibrinogen at poly(octadecene-alt-maleic acid) thin films.
Alternative synthesis of 9-{3-[(diisopropoxyphosphoryl)methoxy]-2-hydroxypropyl}adenine and its free phosphonates substituted at the C-8 position of purine base
Authors: Janeba Zlatko , Masojídková Milena , Holý Antonín
Published: March 2010

For its high therapeutic effect, (S)-9-[3-hydroxy-2-(phosphonomethoxy)propyl]adenine (HPMPA) is an important member of a class of acyclic nucleoside phosphonates (ANPs). Although its constitutional isomer, 9-[2-hydroxy-3-(phosphonomethoxy)propyl]adenine (iso-HPMPA), exhibits no antiviral activity, our general interest in C-8 substituted adenine ANPs led us to prepare certain iso-HPMPA derivatives modified at the C-8 position of adenine. Novel alkylating agent, diisopropyl {[2-(tetrahydro-2-pyranyl)oxy-3-tosyloxypropoxy]methyl}phosphonate (9), was prepared by procedure starting from allyl alcohol (4). 9-{3-[(Diisopropoxyphosphoryl)methoxy]-2-hydroxypropyl}adenine (12) was prepared by alkylation of adenine with the alkylating agent 9 followed by acid hydrolysis, although elimination by-product 9-{3-[(diisopropoxyphosphoryl)methoxy]prop-1-enyl}adenine (11) predominated in the reaction mixture. Bromination of the compound 12 gave 8-bromoadenine derivative 13 quantitatively. Nucleophilic substitutions of the bromine atom of compound 13 with N- and O-nucleophiles, followed by phosphonate deprotection, afforded the free phoshonic acids 15–18.
CORWIN–GREENLEAF MULTIPLICITY FUNCTIONS FOR HERMITIAN SYMMETRIC SPACES AND MULTIPLICITY-ONE THEOREM IN THE ORBIT METHOD
Authors: NASRIN SALMA
Published: March 2010

Kobayashi's multiplicity-free theorem asserts that irreducible unitary highest-weight representations π are multiplicity-free when restricted to every symmetric pair if π is of scalar type. The aim of this paper is to find the "classical limit" of this multiplicity-free theorem in terms of the geometry of two coadjoint orbits, for which the correspondence is predicted by the Kirillov–Kostant–Duflo orbit method.

For this, we study the Corwin–Greenleaf multiplicity function [Formula: see text] for Hermitian symmetric spaces G/K. First, we prove that [Formula: see text] for any G-coadjoint orbit [Formula: see text] and any K-coadjoint orbit [Formula: see text] if [Formula: see text]. Here, 𝔤 = 𝔨 + 𝔭 is the Cartan decomposition of the Lie algebra 𝔤 of G.

Second, we find a necessary and sufficient condition for [Formula: see text] by means of strongly orthogonal roots. This criterion may be regarded as the "classical limit" of a special case of the Hua–Kostant–Schmid–Kobayashi branching laws of holomorphic discrete series representations with respect to symmetric pairs.
DEGENERATE COMPLEX MONGE–AMPÈRE EQUATIONS OVER COMPACT KÄHLER MANIFOLDS
Authors: DEMAILLY JEAN-PIERRE , PALI NEFTON
Published: March 2010

We prove the existence and uniqueness of the solutions of some very general type of degenerate complex Monge–Ampère equations, and investigate their regularity. These types of equations are precisely what is needed in order to construct Kähler–Einstein metrics over irreducible singular Kähler spaces with ample or trivial canonical sheaf and singular Kähler–Einstein metrics over varieties of general type.
FIRST-ORDER QUANTUM CORRECTION TO THE GROUND-STATE ENERGY DENSITY OF TWO-DIMENSIONAL HARD-SPHERE BOSE ATOMS
Authors: KIM SANG-HOON , DAS MUKUNDA P.
Published: March 2010

Divergence exponents of the first-order quantum correction of a two-dimensional hard-sphere Bose atoms are obtained by an effective field theory method. The first-order correction to the ground-state energy density with respect to the zeroth-order is given by [Formula: see text], where D is the spatial dimension, and γ is the gas parameter (γ = naD). As D →2, α = α′ = 1. We show that the first-order quantum correction of the energy density is not perturbative in low dimensions of D < 2.2 regardless of any gas parameter which is much less than unity.
BOGOLIUBOV'S VISION: QUASIAVERAGES AND BROKEN SYMMETRY TO QUANTUM PROTECTORATE AND EMERGENCE
Authors: KUZEMSKY A. L.
Published: March 2010

In the present interdisciplinary review, we focus on the applications of the symmetry principles to quantum and statistical physics in connection with some other branches of science. The profound and innovative idea of quasiaverages formulated by N. N. Bogoliubov, gives the so-called macro-objectivation of the degeneracy in the domain of quantum statistical mechanics, quantum field theory and quantum physics in general. We discuss the complementary unifying ideas of modern physics, namely: spontaneous symmetry breaking, quantum protectorate and emergence. The interrelation of the concepts of symmetry breaking, quasiaverages and quantum protectorate was analyzed in the context of quantum theory and statistical physics. The chief purposes of this paper were to demonstrate the connection and interrelation of these conceptual advances of the many-body physics and to try to show explicitly that those concepts, though different in details, have certain common features. Several problems in the field of statistical physics of complex materials and systems (e.g., the chirality of molecules) and the foundations of the microscopic theory of magnetism and superconductivity were discussed in relation to these ideas.
IMPLEMENTATION OF NON-ADIABATIC GEOMETRIC QUANTUM GATE IN QUANTUM CIRCUIT
Authors: JI Y. H. , XU L. , XU B. , WANG Z. S.
Published: March 2010

A scheme is investigated to realize non-adiabatic geometric quantum computation by directly varying the external parameters of quantum circuit. More intriguingly, we illustrate in detail how to control the parameters of the system to remove the dynamical phase. The scheme depends completely on manipulating both the circuit parameters and the magnetic field parameters, which does not require any rotation operation as done in the conventional geometric gates or the unconventional geometric gates.
HEATING RATE EFFECTS ON THERMOLUMINESCENCE OF BaSO4:Eu+PTFE PREPARED AT ININ-MEXICO
Authors: GONZALEZ P. R. , FURETTA C. , CRUZ-ZARAGOZA E. , AZORÍN J.
Published: March 2010

In this work, we show the influence of heating rate (H.R.) on the thermoluminescence (TL) signal of BaSO 4 activated by Eu ions. The maximum temperature, the TL integral, the activation energy, the frequency factor and full width at half maximum of the TL glow-peak as a function of the H.R. were studied. The TL reading system used was a Harshaw TL reader model 4000, with constant H.R. in the range from 2 to 12 K/s. The irradiation dose was 0.1 Gy from 60 Co in all cases. The kinetic parameters and their dependence on the H.R. were evaluated using the sequential quadratic programming glow curve deconvolution (SQPGCD). The experimental results showed that as the H.R. increases, the IM shifts to higher temperature; similar behavior of the kinetics parameters were obtained.
ANALYTICAL STUDY ON NONLINEAR DIFFERENTIAL–DIFFERENCE EQUATIONS VIA A NEW METHOD
Authors: ZHAO HONG
Published: March 2010

Based on the computerized symbolic computation, a new rational expansion method using the Jacobian elliptic function was presented by means of a new general ansätz and the relations among the Jacobian elliptic functions. The results demonstrated an effective direction in terms of a uniformed construction of the new exact periodic solutions for nonlinear differential–difference equations, where two representative examples were chosen to illustrate the applications. Various periodic wave solutions, including Jacobian elliptic sine function, Jacobian elliptic cosine function and the third elliptic function solutions, were obtained. Furthermore, the solitonic solutions and trigonometric function solutions were also obtained within the limit conditions in this paper.
FINITE POSETS AND THEIR REPRESENTATION ALGEBRAS
Authors: GERSTENHABER MURRAY , SCHAPS MARY
Published: March 2010

A finite poset (P ≼ S) determines a finite dimensional algebra TP over the field 𝔽 of two elements, with an upper triangular representation. We determine the structure of the radical of the representation algebra A of the monoid (TP,·) over a field of characteristic different from 2. We also consider degenerations of A over a complete discrete valuation ring with residue field of characteristic 2.
THOMPSON'S GROUP V FROM A DYNAMICAL VIEWPOINT
Authors: SALAZAR-DÍAZ OLGA PATRICIA
Published: March 2010

Thompson's group V can be thought of as the group of automorphisms of a certain algebra or as a subgroup of the group of self homeomorphisms of the Cantor set. Thus, the dynamics of an element of V can be studied. We analyze the dynamics in detail and use the analysis to give another solution of the conjugacy problem in V.
BICYCLIC SUBSEMIGROUPS IN AMALGAMS OF FINITE INVERSE SEMIGROUPS
Authors: RODARO EMANUELE
Published: March 2010

It is well known that an inverse semigroup is completely semisimple if and only if it does not contain a copy of the bicyclic semigroup. We characterize the amalgams [S1, S2; U] of two finite inverse semigroups S1, S2whose free product with amalgamation is completely semisimple and we show that checking whether the amalgamated free product of finite inverse semigroups contains a bicyclic subsemigroup is decidable by means of a polynomial time algorithm with respect to max {|S1|,|S2|}. Moreover we consider amalgams of finite inverse semigroups respecting the [Formula: see text]-order proving that the free product with amalgamation is completely semisimple and we also provide necessary and sufficient conditions for the [Formula: see text]-classes to be finite.
FINITENESS PROPERTIES OF LOCAL COHOMOLOGY MODULES AND GENERALIZED REGULAR SEQUENCES
Authors: BAHMANPOUR KAMAL , FARAMARZI SEADAT OLLAH , NAGHIPOUR REZA
Published: March 2010

Let R be a commutative Noetherian ring, 𝔞 an ideal of R, and M an R-module. The purpose of this paper is to show that if M is finitely generated and dim M/𝔞M > 1, then the R-module ∪{N|N is a submodule of [Formula: see text] and dim N ≤ 1} is 𝔞-cominimax and for some x ∈ R is Rx + 𝔞-cofinite, where t ≔ gdepth (𝔞, M). For any nonnegative integer l, it is also shown that if R is semi-local and M is weakly Laskerian, then for any submodule N of [Formula: see text] with dim N ≤ 1 the associated primes of [Formula: see text] are finite, whenever [Formula: see text] for all i < l. Finally, we show that if (R, 𝔪) is local, M is finitely generated, [Formula: see text] for all i < l, and [Formula: see text] then there exists a generalized regular sequence x1, …, xl ∈ 𝔞 on M such that [Formula: see text].
BAER ENDOMORPHISM RINGS AND ENVELOPES
Authors: MAO LIXIN
Published: March 2010

R is called a Baer ring if the left annihilator of every nonempty subset of R is a direct summand of RR. R is said to be a left AFG ring in case the left annihilator of every nonempty subset of R is a finitely generated left ideal. In this paper, we study Baer rings and AFG rings of endomorphisms of modules in terms of envelopes. Some known results are extended.
MATRIX REPRESENTATION OF RECTANGULAR BANDS OF SEMIGROUPS
Authors: GUO XIAOJIANG , SHUM K. P.
Published: March 2010

Abundant semigroups expressed as a perfect rectangular band of adequate semigroups will be investigated. A known theorem of Pastijn–Petrich in 1984 on perfect rectangular bands of inverse semigroups will be generalized from the class of regular semigroups to the class of abundant semigroups. A Rees matrix representation of such abundant semigroups will be established and some characterization theorems will be consequently given.
THE IDEALS OF AN IDEAL EXTENSION
Authors: MESYAN ZACHARY
Published: March 2010

Given two unital associative rings R ⊆ S, the ring S is said to be an ideal (or Dorroh) extension of R if S = R ⊕ I, for some ideal I ⊆ S. In this note, we investigate the ideal structure of an arbitrary ideal extension of an arbitrary ring R. In particular, we describe the Jacobson and upper nil radicals of such a ring, in terms of the Jacobson and upper nil radicals of R, and we determine when such a ring is prime and when it is semiprime. We also classify all the prime and maximal ideals of an ideal extension S of R, under certain assumptions on the ideal I. These are generalizations of earlier results in the literature.
HIGHER-ORDER CLASS GROUPS AND BLOCK MONOIDS OF KRULL MONOIDS WITH TORSION CLASS GROUP
Authors: SCHMID WOLFGANG A.
Published: March 2010

Extensions of the notion of a class group and a block monoid associated to a Krull monoid with torsion class group are introduced and investigated. Instead of assigning to a Krull monoid only one abelian group (the class group) and one monoid of zero-sum sequences (the block monoid), we assign to it a recursively defined family of abelian groups, the first being the class group, and do alike for the block monoid. These investigations are motivated by the aim of gaining a more detailed understanding of the arithmetic of Krull monoids, including Dedekind and Krull domains, both from a technical and conceptual point of view. To illustrate our method, some first arithmetical applications are presented.
MULTIPLICATIVE JORDAN DECOMPOSITION IN GROUP RINGS OF 2, 3-GROUPS
Authors: LIU CHIA-HSIN , PASSMAN D. S.
Published: March 2010

In this paper, we essentially finish the classification of those finite 2, 3-groups G having integral group rings with the multiplicative Jordan decomposition (MJD) property. If G is abelian or a Hamiltonian 2-group, then it is clear that ℤ[G] satisfies MJD. Thus, we need only consider the nonabelian case. Recall that the 2-groups with MJD were completely determined by Hales, Passi and Wilson, while the corresponding 3-groups were almost completely determined by the present authors. Thus, we are concerned here, for the most part, with groups whose order is divisible by 6. As it turns out, there are precisely three nonabelian 2, 3-groups, of order divisible by 6, with ℤ[G] satisfying MJD. These have orders 6, 12, and 24. In view of another result of Hales, Passi and Wilson, this completes a significant portion of the classification of all finite groups with MJD.