bluuebunny/crossref_metadata_2025_split huggingface dataset:
Timing of radiation in children with medulloblastoma/PNET
Authors: Santos Marcos A. , Viégas Célia M.P. , Servidoni Renata A. , Barros Mario H.M. , Pinel Maria Isabel , Araújo Carlos M.M. 
Published: October 2006

AbstractBackgroundTo evaluate the importance of timing of radiation therapy in children with PNET/medulloblastoma, treated at the Brazilian National Cancer Institute (INCA).ProcedureThe records of 101 children with confirmed diagnosis of medulloblastoma were retrospectively reviewed. Patients had a median follow‐up of 48 months (0.5–241 months). The age varied from 0.8 to 17.5 years (median: 7.6 years) and 21.7% were 3 years old or younger.ResultsAccording to the data collected from patients that received treatment for medulloblastoma from 1983 to 2001, the overall survival (OS) rate was 53% and the Disease Free Survival (DFS) rate was 40%. Multivariate analysis showed that under age 3 years, presence of neoplasic cells in the cerebrospinal fluid (CSF) at presentation or subtotal tumor resection resulted in a worse OS. The patients that received a biological effective dose (BED) greater than 44 Gy10 had better prognosis. Two‐thirds of the patients had complete response after the initial treatment. Among them, 50% (34 patients) recurred, and of those 34 patients, 42% of them (14 patients) had recurrence in the posterior fossa.ConclusionSurgery with total resection of the tumor and absence of neoplasic cells in the CSF are effective predictors of better OS. Radiotherapy was more effective when a BED was greater than 44 Gy10. Pediatr Blood Cancer © 2006 Wiley‐Liss, Inc.
Dynamics and assembly of the cytolethal distending toxin
Authors: Hu Xin , Stebbins C. Erec 
Published: October 2006

AbstractThe cytolethal distending toxin (CDT) is a widespread bacterial toxin that consists of an active subunit CdtB with nuclease activity and two ricin‐like lectin domains, CdtA and CdtC, that are involved in the delivery of CdtB into the host cell. The three subunits form a tripartite complex that is required to achieve the fully active holotoxin. In the present study we investigate the assembly and dynamic properties of the CDT holotoxin using molecular dynamics simulations and binding free energy calculations. The results have revealed that CdtB likely adopts a different conformation in the unbound state with a closed DNA binding site. The two characterized structural elements of the aromatic patch and groove on the CdtA and CdtC protein surfaces exhibit high mobility, and free energy calculations show that the heterodimeric complex CdtA‐CdtC, as well as the CdtA‐CdtB and CdtB‐CdtC sub‐complexes are less energetically stable as compared to the binding in the tripartite complex. Analysis of the dynamical cross‐correlation map reveals information on the correlated motions and long‐range interplay among the CDT subunits associated with complex formation. Finally, the estimated binding free energies of subunit interactions are presented, together with the free energy decomposition to determine the contributions of residues for both binding partners, providing insight into the protein–protein interactions in the CDT holotoxin. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Bombesin analogs containing α‐amino‐isobutyric acid with potent anticancer activity
Authors: Prasad Sudhanand , Mathur Archna , Gupta Neena , Jaggi Manu , Singh Anu T. , Rajendran Praveen , Sanna Vinod K. , Datta Kakali , Mukherjee Rama 
Published: October 2006

AbstractSix octapeptide bombesin (BN) analogs were synthesized by substituting α‐aminoisobutyric acid (Aib), in place of Ala9 or Gly11, or both, in the [D‐Phe6, desMet14]‐BN (6–14) sequence: D‐Phe6‐Gln7‐Trp8‐Ala9‐Val10‐Gly11‐His12‐Leu13‐NH2 (P0). Additionally, Leu13 was replaced with isoleucine in two analogs and one of the analogs was butanoylated at the N‐terminus. The antiproliferative activity of the analogs was tested in vitro on human pancreatic (MiaPaCa‐2) and colon cancer (SW620, HT29 and PTC) cell lines using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay. The analogs demonstrated anticancer activity in the above cell lines at concentrations ranging from 0.01 nM to 1 µM. One of the analogs, P6, was evaluated for in vivo tumor regression in a xenograft model of human primary colon cancer in athymic nude mice and was found to cause significant reduction in tumor volume. NMR and molecular dynamics (MD) simulation studies for this analog revealed the presence of a mixed 310/α‐helical structure. This study demonstrates that the designed BN analogs retain their anticancer activity after the incorporation of the constrained amino acid, Aib, and are potential molecules for future use in cancer therapy and drug targeting. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
Atomic and molecular cubature grids
Authors: Hall G. G. , Rees D. 
Published: October 2006

AbstractThis article presents cubature grids of the Gaussian type that are adapted for the purpose of wave function calculation on atoms and molecules. The problems of the singularity at the nucleus, the derivatives in the kinetic energy, and the presence of two‐electron integrals are shown to be resolved. Each grid has a definite degree of accuracy so that it reproduces the exact values of all the integrals in a defined class. Seventh‐degree accuracy can be obtained from a grid of 143 nodes. The grids are applied, as simple illustrations, to well‐known self‐consistent field (SCF) calculations on helium. Grids for homonuclear diatomics are also discussed and an illustrative application given to a homonuclear diatomic molecule. A comparison between a molecular grid and the union of two unmodified atomic grids shows that overlaps and distortions in weights can occur to the extent that this is not practical. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Transport layer protocols and architectures for satellite networks
Authors: Caini Carlo , Firrincieli Rosario , Marchese Mario , Cola Tomaso de , Luglio Michele , Roseti Cesare , Celandroni Nedo , Potortí Francesco 
Published: October 2006

AbstractDesigning efficient transmission mechanisms for advanced satellite networks is a demanding task, requiring the definition and the implementation of protocols and architectures well suited to this challenging environment. In particular, transport protocols performance over satellite networks is impaired by the characteristics of the satellite radio link, specifically by the long propagation delay and the possible presence of segment losses due to physical channel errors. The level of impact on performance depends upon the link design (type of constellation, link margin, coding and modulation) and operational conditions (link obstructions, terminal mobility, weather conditions, etc.). To address these critical aspects a number of possible solutions have been presented in the literature, ranging from limited modifications of standard protocols (e.g. TCP, transmission control protocol) to completely alternative protocol and network architectures. However, despite the great number of different proposals (or perhaps also because of it), the general framework appears quite fragmented and there is a compelling need of an integration of the research competences and efforts. This is actually the intent of the transport protocols research line within the European SatNEx (Satellite Network of Excellence) project. Stemming from the authors' work on this project, this paper aims to provide the reader with an updated overview of all the possible approaches that can be pursued to overcome the limitations of current transport protocols and architectures, when applied to satellite communications. In the paper the possible solutions are classified in the following categories: optimization of TCP interactions with lower layers, TCP enhancements, performance enhancement proxies (PEP) and delay tolerant networks (DTN). Advantages and disadvantages of the different approaches, as well as their interactions, are investigated and discussed, taking into account performance improvement, complexity, and compliance to the standard semantics. From this analysis, it emerges that DTN architectures could integrate some of the most efficient solutions from the other categories, by inserting them in a new rigorous framework. These innovative architectures therefore may represent a promising solution for solving some of the important problems posed at the transport layer by satellite networks, at least in a medium‐to‐long‐term perspective. Copyright © 2006 John Wiley & Sons, Ltd.
History, theory and the narrative turn in IR
Authors: ROBERTS GEOFFREY 
Published: October 2006

My lecture has three main themes:First, the nature and extent of the turn to history and narrative in the study of
international relations.Second, the contribution of narrative history to IR theory, not as an adjunct or
empirical resource, but as a theoretical perspective in its own right. Narrative
historians of international relations may not adhere to an explicit theory of international
relations but they do practice an implicit philosophy of history, a philosophy
as sophisticated and theoretically fertile as any other IR theoretical approach.
The growth of government spending and the money supply
Authors: Kandil Magda 
Published: October 2006

PurposeUsing quarterly data for a sample of 17 industrial countries, the purpose of this paper is to study asymmetry in the face of monetary shocks compared to government spending shocks.Design/methodology/approachThe paper outlines demand and supply channels determining the asymmetric effects of monetary and fiscal policies. The time‐series model is presented and an analysis of the difference in the asymmetric effects of monetary and fiscal shocks within countries is presented. There then follows an investigation of the relevance of demand and supply conditions to the asymmetric effects of monetary and fiscal shocks. The implications of asymmetry are contrasted across countries.FindingsFluctuations in real output growth, price inflation, wage inflation, and real wage growth vary with respect to anticipated and unanticipated shifts to the money supply, government spending, and the energy price. The asymmetric flexibility of prices appears a major factor in differentiating the expansionary and contractionary effects of fiscal and monetary shocks. Higher price inflation, relative to deflation, exacerbates output contraction, relative to expansion, in the face of monetary shocks. In contrast, larger price deflation, relative to inflation, moderates output contraction, relative to expansion in the face of government spending shocks. The growth of output and the real wage decreases, on average, in the face of monetary variability in many countries. Moreover, the growth of real output and the real wage increases, on average, in the face of government spending variability in many countries. Asymmetry differentiates the effects of monetary and government spending shocks within and across countries. The degree and direction of asymmetry provide a new dimension to differentiate between monetary and fiscal tools in the design of stabilization policies.Originality/valueThe paper's evidence sheds light on the validity of theoretical models explaining asymmetry in the effects of demand‐side stabilization policies. Moreover, the evidence should alert policy makers to the need to relax structural and institutional constraints to maximize the benefits of stabilization policies and minimize the adverse effects on economic variables.
Cournot's model applied to cellphone service in Colombia, 1995‐2001
Authors: Jhon James Mora R. 
Published: October 2006

PurposeThe purpose of this paper is to develop and empirically test the conditions that describe adjustment velocities to reach equilibrium under Cournot's duopoly model.Design/methodology/approachThe paper uses a vector error correction (VEC) framework as the basis for determining and testing adjustment velocities using data about cellphone service in Colombia in the time period from 1995 to 2001.FindingsEmpirical evidence suggests the following: first of all, companies operating in the cellphone market behave as cournot's competitors and have constant marginal costs; secondly, cellphone companies operating in the eastern zone of Colombia are in long‐term equilibrium; and lastly, equilibrium adjustment velocities are statistically significant. As predicted by theory, in terms of welfare, the existence of equilibrium in Cournot's model implies that cellphone users in the eastern zone of Colombia enjoy a small consumer surplus.Originality/valueTesting the microeconomic implications of the equilibrium dynamics of Cournot's model, using a VEC framework.
College students, cookies and collections: using holiday study breaks to encourage undergraduate research in special collections
Authors: Summerfield Hammerman Susan , Kern Barbara , Starkey Rebecca , Taylor Anne 
Published: October 2006

PurposeTo launch the University of Chicago Library's study break program for undergraduate students which introduces them to rare book and manuscript collections.Design/methodology/approachTwo study breaks, Love in the Stacks and Things that Go Bump in the Stacks' are described in detail, including selecting material for viewing, marketing the event and basic logistics. In addition the authors discuss the educational materials they created for distribution at the event, attendance, the feedback and comments they received and finally what they learned.FindingsProvides information about the events, and looks towards future events. Discusses how book and manuscript collections can be intimidating to undergraduate students, who often believe the materials are for the use of faculty or other “serious” scholars.Originality/valueThis paper describes an innovative program that has successfully introduced undergraduate students to Special Collections, and provides information which would allow others to offer a similar program.
Stereoscopic imaging
Authors: Connolly Christine 
Published: October 2006

PurposeTo explore the phenomenon of stereoscopic vision and its exploitation in engineering and other professional applications, and in entertainment.Design/methodology/approachStarts with a review of how stereo vision works, and the techniques used in 3D movies to present the illusion of depth and movement at right angles to the screen. Looks at some engineering products that build on these techniques, and then at the development of 3D television, based on a different image separation method. Finally looks at developments in stereo machine vision.FindingsA variety of techniques exist to present left and right views of a scene to the correct eyes and stimulate 3D perception: for example, light‐filtering, alternate‐frame sequencing and optical separation. Fatigue occurs when there is crosstalk between those images, or when the images are presented at too low a frame rate. Many computer modelling software providers produce programs with 3D‐viewing capability for professional engineers. There are some exciting recent developments, such as add‐on PC stereo systems, and 3D TV.Originality/valueMakes the general scientist aware of the wide range of professional uses of stereo vision, and of the engineering challenges behind 3D film and television.
Labour market inactivity due to family care in Luxembourg
Authors: Valentova Marie 
Published: October 2006

PurposeThe purpose of this paper is to deal with an issue of female labour inactivity in the Grand Duchy of Luxembourg, more specifically women in the 16‐65 age category who are long‐term inactive in the formal labour market due to family responsibilities. This group currently represents one‐third of the female population of working age in the country.Design/methodology/approachThe core of the analysis lies in examining the main socio‐demographic characteristics of family carers. First, the paper provides descriptive analysis of socio‐demographic background of women who are inactive in the labour market. Second it examines the influence of selected socio‐demographic characteristics on the woman's choice not to participate in the labour market due to family care. In the conclusions, based on the outcomes of the conducted analysis and information on the existing welfare setting in the country, the paper suggests policies which should facilitate greater participation of these women in the labour market.FindingsReferring to the presented theory and to the findings, it can be concluded that Luxembourg is a country with a conservative orientation where women, especially those with lower education, who are married, multiple‐mothers, older than 35 years, Luxembourg nationals, and who are living in households receiving higher social benefits, choose to withdraw from the labour market due to family responsibilities.Originality/valueGiven the lack of more detailed information concerning labour market inactivity of Luxembourgish women and their labour market potential, the fact that the female labour inactivity in the country has never been examined in light of the theory of welfare states’ regimes, and the pressing Lisbon employment strategy targets, this paper represents the first in depth empirical attempt to describe and explain the phenomenon of female labour market inactivity in the Grand Duchy of Luxembourg and provides evidence based policy suggestions which could promote women's labour market participation. The outcomes of the cross‐sectional approach applied in this paper could serve as a base for further more sophisticated analyses of the issue of female inactivity due to family care in Luxembourg. It would be particularly interesting to focus on longitudinal analysis of transistions in and out labour market inactivity and analyze the main socio‐demographic determinants of these transitions.
Predicting the organisational adoption of B2C e‐commerce: an empirical study
Authors: To March L. , Ngai E.W.T. 
Published: October 2006

PurposeUsing the literature on innovation research, this paper proposes to establish and empirically test a prediction model which consists of four major factors in the adoption of online retailing by organisations, namely relative advantage, competitive pressure, channel conflict and technical resource competence.Design/methodology/approachData collected from 140 different companies indicate strong empirical support for the model. Relevant hypotheses were derived and tested by logistic regression analysis.FindingsThe results revealed that relative advantage, competitive pressure and technical resource competence have positive effects on the adoption of online retailing.Research limitations/implicationsThe research was conducted in Hong Kong, which may limit the generalisability of the findings.Practical implicationsWhile many studies contribute to an understanding of behaviours of the online market from a consumer perspective, there are few concrete investigations of the organisational viewpoint. With data obtained from practitioners in 140 companies, the major factors of online retailing adoption are addressed, providing strategic directions for managers to evaluate its adoption.Originality/valueAlthough many conceptual papers and case studies have identified different potential factors affecting the adoption of online retailing, there are few empirical studies which establish prediction models for its adoption. In fact, during the past decade, in spite of growing interest in B2C transactions, organisations have not necessarily rushed towards adopting online sales. It is critical to have more empirical evidence of the factors affecting the adoption of online sales to help managers further access the benefits of its continuous and potential development. This study attempts to fill the research gap.
Using systems dynamics for human resources management in information systems security
Authors: Trček Denis 
Published: October 2006

PurposeTo enable quantitative and qualitative modelling of information systems security management that takes into account technology and human factor.Design/methodology/approachThe approach is based on systems dynamics and it is done in two phases. In the first phase two basic qualitative models are developed, while in the second phase a possibility to further develop them into quantitative models is studied.FindingsAppropriate approach to IS security management requires addressing “hard” and “soft” factors. Further, to enable quantitative study of such systems, which are highly non‐linear, exact analytical (mathematically rigorous) treatment is close to impossible. Thus, computer simulations have to be used. One appropriate methodological answer to the above requirements is systems (business) dynamics.Research limitations/implicationsResearch limitations are partially related to system dynamics, which operates on an aggregates level. This prevents or makes harder study of phenomena at the micro level, from where the above‐mentioned aggregates emerge. Further, many sub‐areas need further standardisation to enable more realistic simulations – one such case is security policy standardisation and quantification. Similar holds true for threats/vulnerabilities and related taxonomies.Practical implicationsThe research presents one of first steps in the direction that could provide quantitative models for effective IS security policy management in organisations.Originality/valueThe research presents two models, one for risk management and the other, which is a generic model that identifies basic variables that have to be addressed for IS security management. Further, findings can be used for security awareness courses.
Innovative influence
Authors: Medvedeva Tatyana A. 
Published: October 2006

PurposeTo describe experience of introducing contemporary West management methods in Russian University's management courses and in practice of West‐Siberian rail road management.Design/methodology/approachThis paper analyzes an experience of innovative influence of a Human Resource Development Center within the Institute of Prospective Transport Technologies and Training of Human Resources, Siberian State University of Transport (Novosibirsk, Russia). Emphasizes the mechanism of innovative influence in time of transitions on the management of organizations through the education of managers.FindingsProvides information about process of transformation on the micro‐level. Most of the work on transitions has been based on macro‐approach. An organization enables closer contact among people. Example of the applicability the methods available in the West to the situation in Russia. Provides information about how do “mentalities” change.Research limitations/implicationsIt is not a general approach to make innovative influence.Practical implicationsA useful example of using technology of participation for making changes in organization with complicated cultural environment.Originality/valueThis paper helps to understand the problems (obstacles) people have in transitional countries and offers practical help on the process of changes.