Showing papers by "Linköping University published in 2004"
TL;DR: It is suggested that prostate tumors can be usefully classified according to their gene expression patterns, and these tumor subtypes may provide a basis for improved prognostication and treatment stratification.
Abstract: Prostate cancer, a leading cause of cancer death, displays a broad range of clinical behavior from relatively indolent to aggressive metastatic disease. To explore potential molecular variation underlying this clinical heterogeneity, we profiled gene expression in 62 primary prostate tumors, as well as 41 normal prostate specimens and nine lymph node metastases, using cDNA microarrays containing ≈26,000 genes. Unsupervised hierarchical clustering readily distinguished tumors from normal samples, and further identified three subclasses of prostate tumors based on distinct patterns of gene expression. High-grade and advanced stage tumors, as well as tumors associated with recurrence, were disproportionately represented among two of the three subtypes, one of which also included most lymph node metastases. To further characterize the clinical relevance of tumor subtypes, we evaluated as surrogate markers two genes differentially expressed among tumor subgroups by using immunohistochemistry on tissue microarrays representing an independent set of 225 prostate tumors. Positive staining for MUC1, a gene highly expressed in the subgroups with “aggressive” clinicopathological features, was associated with an elevated risk of recurrence (P = 0.003), whereas strong staining for AZGP1, a gene highly expressed in the other subgroup, was associated with a decreased risk of recurrence (P = 0.0008). In multivariate analysis, MUC1 and AZGP1 staining were strong predictors of tumor recurrence independent of tumor grade, stage, and preoperative prostate-specific antigen levels. Our results suggest that prostate tumors can be usefully classified according to their gene expression patterns, and these tumor subtypes may provide a basis for improved prognostication and treatment stratification.
1,315 citations
TL;DR: X-ray absorption spectroscopy and x-ray Raman scattering were used to probe the molecular arrangement in the first coordination shell of liquid water and set a strong limit for possible local structure distributions in liquid water.
Abstract: X-ray absorption spectroscopy and x-ray Raman scattering were used to probe the molecular arrangement in the first coordination shell of liquid water. The local structure is characterized by comparison with bulk and surface of ordinary hexagonal ice Ih and with calculated spectra. Most molecules in liquid water are in two hydrogen– bonded configurations with one strong donor and one strong acceptor hydrogen bond in contrast to the four hydrogen– bonded tetrahedral structure in ice. Upon heating from 25°C to 90°C, 5 to 10% of the molecules change from tetrahedral environments to two hydrogen– bonded configurations. Our findings are consistent with neutron and x-ray diffraction data, and combining the results sets a strong limit for possible local structure distributions in liquid water. Serious discrepancies with structures based on current molecular dynamics simulations are observed.
1,278 citations
Book•
22 Jan 2004TL;DR: This chapter discusses Modelica, the Modelica Language, and its applications, which include Discrete Event, Hybrid, and Concurrency Modeling, and related Object-Oriented Modeling Languages.
Abstract: Part I: Introduction. Chapter 1: Introduction to Modeling and Simulation. Chapter 2: A Quick Tour of Modelica. Part II: The Modelica Language. Chapter 3: Classes, Types, and Declarations. Chapter 4: Inheritance, Modifications, and Generics. Chapter 5: Components, Connectors, and Connections. Chapter 6: Literals, Operators, and Expressions. Chapter 7: Arrays. Chapter 8: Equations. Chapter 9: Algorithms and Functions. Chapter 10: Packages. Chapter 11: Annotations, Units, and Quantities. Part III: Modeling and Applications. Chapter 12: System Modeling Methodology and Continuous Model Representation. Chapter 13: Discrete Event, Hybrid, and Concurrency Modeling. Chapter 14: Basic Laws of Nature. Chapter 15: Application Examples. Chapter 16: Modelica Library Overview. Part IV: Technology and Tools. Chapter 17: A Mathematical Representation for Modelica Models. Chapter 18: Techniques and Research. Chapter 19: Environments. Appendix A: Modelica Formal Syntax. Appendix B: Mathematica-style Modelica Syntax. Appendix C: Solutions for Exercises. Appendix D: Modelica Standard Library. Appendix E: Modelica Scripting Commands. Appendix F: Related Object-Oriented Modeling Languages. Appendix G: A Modelica XML Representation. References. Index.
1,133 citations
TL;DR: Maternal morbid obesity in early pregnancy is strongly associated with a number of pregnancy complications and perinatal conditions.
1,087 citations
TL;DR: In this paper, regional and global lake methane emissions, contributing to the greenhouse effect, are poorly known, and the authors develop a method to identify hot spots of methane production in the landscape.
Abstract: [ 1] Lake sediments are "hot spots'' of methane production in the landscape. However, regional and global lake methane emissions, contributing to the greenhouse effect, are poorly known. We develop ...
902 citations
TL;DR: In this article, the development and diffusion of technologies that utilize renewable energy sources in Germany, Sweden and the Netherlands is analyzed. And the authors enlarges the life cycle model of industry evolution to one where the focus is on the formation and evolution of new technological systems, explaining success and failures in shifting from a formative phase into one characterized by positive feedbacks.
Abstract: This paper analyses the development and diffusion of technologies that utilize renewable energy sources in Germany, Sweden and the NetherlandsThe analysis enlarges the life cycle model of industry evolution to one where the focus is on the formation and evolution of new technological systems Particular focus is on explaining success and failures in shifting from a formative phase into one characterized by positive feedbacks A set of challenges is identified for policy makers attempting to influence the process of transforming the energy sector
862 citations
TL;DR: Project-based organizations as mentioned in this paper are an organizational form that involves the creation of temporary systems for the performance of project tasks (Lundin and Soderholm 1995; DeFillippi 2002).
Abstract: Project-based organizations refer to a variety of organizational forms that involve the creation of temporary systems for the performance of project tasks (Lundin and Soderholm 1995; DeFillippi 2002). Project-based organizations have received increasing attention in recent years as an emerging organizational form to integrate diverse and specialized intellectual resources and expertise (DeFillippi and Arthur 1998; Hobday 2000; Gann and Salter 2000; Keegan and Turner 2002; Lindkvist 2004). Recent interest in the emerging knowledge economy has reinforced the view that project organizations in their many varieties are a fast and flexible mode of organizing knowledge resources. Project-based organizations can circumvent traditional barriers to organizational change and innovation, since each project is presented as a temporary, relatively short-lived, phenomenon. As such, it does not pose the same threat to vested interests as would the creation of a permanent new department or division. Moreover, project-based organizations allow for low-cost experiments. Because of their limited duration, project-based organizations do not constitute irreversible resource commitments of fixed costs. Hence, companies and other types of organization may launch a variety of ventures through project-based organizations and may terminate unsuccessful ventures at low cost and little disturbance to the organizational sponsor (DeFillippi 2002). Project-based organizations are found in a wide range of industries. These include consulting and professional services (e.g. accounting, advertising, architectural design, law, management consulting, public relations), cultural industries (e.g. fashion, film-making, video games, publishing), high technology (e.g. software, computer hardware, multimedia), and complex products and systems (e.g. construction, transportation, telecommunications, infrastructure). For many of these industries, project-based organizations are employed to meet the highly differentiated and customized nature of demand, where clients frequently negotiate and interact with project organizers over the ofteninnovative design of products and services (Hobday 1998). However, firms in all types of industries are undertaking projects as a growing part of their operations even while their primary ‘productive’ activity might be volume-based or operations-oriented (e.g. Midler 1995; Keegan and Turner 2002). Hobday (2000) refers to these as project-led organizations and Organization Studies 25(9): 1475–1489 ISSN 0170–8406 Copyright © 2004 SAGE Publications (London, Thousand Oaks, CA & New Delhi) 1475 Authors name
678 citations
TL;DR: The various ways in which the term ‘interaction strength’ has been applied are described and the implications of loose terminology and definition for the development of this field are discussed.
Abstract: Summary 1. Recent efforts to understand how the patterning of interaction strength affects both structure and dynamics in food webs have highlighted several obstacles to productive synthesis. Issues arise with respect to goals and driving questions, methods and approaches, and placing results in the context of broader ecological theory. 2. Much confusion stems from lack of clarity about whether the questions posed relate to community-level patterns or to species dynamics, and to what authors actually mean by the term ‘interaction strength’. Here, we describe the various ways in which this term has been applied and discuss the implications of loose terminology and definition for the development of this field. 3. Of particular concern is the clear gap between theoretical and empirical investigations of interaction strengths and food web dynamics. The ecological community urgently needs to explore new ways to estimate biologically reasonable model coefficients from empirical data, such as foraging rates, body size, metabolic rate, biomass distribution and other species traits. 4. Combining numerical and analytical modelling approaches should allow exploration of the conditions under which different interaction strengths metrics are interchangeable with regard to relative magnitude, system responses, and species identity. 5. Finally, the prime focus on predator‐prey links in much of the research to date on interaction strengths in food webs has meant that the potential significance of nontrophic interactions, such as competition, facilitation and biotic disturbance, has been largely ignored by the food web community. Such interactions may be important dynamically and should be routinely included in future food web research programmes.
594 citations
TL;DR: In this article, the authors argue that too much effort has been dedicated to clarifying the reasons of project success and failure, while downplaying a number of important research questions that need to be discussed in order to further the knowledge about project management.
579 citations
TL;DR: It is shown, by the experimental manipulation of dissolved inorganic 13C in two lakes, that internal primary production is insufficient to support the food webs of these ecosystems, and there is significant subsidy ofThese ecosystems by organic carbon produced outside their boundaries.
Abstract: Ecosystems are supported by organic carbon from two distinct sources. Endogenous carbon is produced by photosynthesis within an ecosystem by autotrophic organisms. Exogenous carbon is produced elsewhere and transported into ecosystems. Consumers may use exogenous carbon with consequent influences on population dynamics, predator-prey relationships and ecosystem processes(1). For example, exogenous inputs provide resources that may enhance consumer abundance beyond levels supported by within-system primary production(2). Exogenous fluxes of organic carbon to ecosystems are often large, but this material is recalcitrant and difficult to assimilate, in contrast to endogenously produced organic matter, which is used more easily(3,4). Here we show, by the experimental manipulation of dissolved inorganic C-13 in two lakes, that internal primary production is insufficient to support the food webs of these ecosystems. Additions of NaH (CO3)-C-13 enriched the C-13 content of dissolved inorganic carbon, particulate organic carbon, zooplankton and fish. Dynamics of C-13 indicate that 40-55% of particulate organic carbon and 22-50% of zooplankton carbon are derived from terrestrial sources, showing that there is significant subsidy of these ecosystems by organic carbon produced outside their boundaries.
557 citations
TL;DR: The aim of this study was to identify risk factors for anastomotic leakage in anterior resection and to assess the role of a temporary stoma and the need for urgent re‐operations in relation to anastOMotic leakage.
Abstract: Objective. Surgical technique and peri-operative management of rectal carcinoma have developed substantially in the last decades. Despite this, morbidity and mortality after anterior resection of the rectum are still important problems. The aim of this study was to identify risk factors for anastomotic leakage in anterior resection and to assess the role of a temporary stoma and the need for urgent re-operations in relation to anastomotic leakage.Patients and methods. In a nine-year period, from 1987 to 1995, a total of 6833 patients underwent elective anterior resection of the rectum in Sweden. A random sample of 432 of these patients was analysed (sample size 6.3%). The associations between death and 10 patient-and surgery-related variables were studied by univariate and multivariate analysis. Data were obtained by review of the hospital files from all patients.Results. The incidence of symptomatic clinically evident anastomotic leakage was 12% (53/432). The 30-day mortality was 2.1% (140/6833). The rate of mortality associated with leakage was 7.5%. A temporary stoma was initially fashioned in 17% (72/432) of the patients, and 15% (11/72) with a temporary stoma had a clinical leakage, compared with 12% (42/360) without a temporary stoma, not significant. Multivariate analysis showed that low anastomosis (≤ 6 cm), pre-operative radiation, presence of intra-opcrative adverse events and male gender were independent risk factors for leakage. The risk for permanent stoma after leakage was 25%. Females with stoma leaked in 3% compared to men with stoma who leaked in 29%. The median hospital stay for patients Arithout leakage was 10 days (range 5-61 days) and for patients with leakage 22 days (3-110 days).Conclusion. In this population based study, 12% of the patients had symptomatic anastomotic leakage after anterior resection of the rectum. Postoperative 30-day mortality was 2.1%. Low anastomosis, pre-operative radiation, presence of intra-operative adverse events and male gender were independent risk factors for symptomatic anastomotic leakage in the multivariate analysis. There was no difference in the use of temporary stoma in patients with or without anastomotic leakage.
TL;DR: This study shows that differences in particle curvature strongly influence the amount of the protein's secondary structure that is perturbed as well as the effects on the protein conformation from the interaction.
Abstract: We have analyzed the adsorption of protein to the surfaces of silica nanoparticles with diameters of 6, 9, and 15 nm. The effects upon adsorption on variants of human carbonic anhydrase with differing conformational stabilities have been monitored using methods that give complementary information, i.e., circular dichroism (CD), nuclear magnetic resonance (NMR), analytical ultracentrifugation (AUC), and gel permeation chromatography. Human carbonic anhydrase I (HCAI), which is the most stable of the protein variants, establishes a dynamic equilibrium between bound and unbound protein following mixture with silica particles. Gel permeation and AUC experiments indicate that the residence time of HCAI is on the order of ∼10 min and slowly increases with time, which allows us to study the effects of the interaction with the solid surface on the protein structure in more detail than would be possible for a process with faster kinetics. The effects on the protein conformation from the interaction have been chara...
TL;DR: Interventions to prevent islet amyloid formation are emerging, with peptide and small molecule inhibitors being developed that could lead to a preservation of beta-cell mass and amelioration of the islet lesion in type 2 diabetes.
Abstract: Islet amyloid deposition is a pathogenic feature of type 2 diabetes, and these deposits contain the unique amyloidogenic peptide islet amyloid polypeptide. Autopsy studies in humans have demonstrat ...
TL;DR: In this paper, the authors used a variety of data and information sources from the same region in subarctic Sweden to show that permafrost and vegetation changes have been associated with increases in landscape scale CH4 emissions in the range of 22-66% over the period 1970 to 2000.
Abstract: Ecosystems along the 0degreesC mean annual isotherm are arguably among the most sensitive to changing climate and mires in these regions emit significant amounts of the important greenhouse gas methane (CH4) to the atmosphere. These CH4 emissions are intimately related to temperature and hydrology, and alterations in permafrost coverage, which affect both of those, could have dramatic impacts on the emissions. Using a variety of data and information sources from the same region in subarctic Sweden we show that mire ecosystems are subject to dramatic recent changes in the distribution of permafrost and vegetation. These changes are most likely caused by a warming, which has been observed during recent decades. A detailed study of one mire show that the permafrost and vegetation changes have been associated with increases in landscape scale CH4 emissions in the range of 22-66% over the period 1970 to 2000.
TL;DR: Data from ten European countries show a striking increase and unusual seasonal pattern of norovirus gastroenteritis in 2002 that occurred concurrently with the emergence of a novel genetic variant, raising questions about the biological properties of the variant and the mechanisms for its rapid dissemination.
TL;DR: Some criteria that should be fulfilled in order to allow the patient to return to sports are presented and adequate muscle strength and performance should be used as a critical criterion.
Abstract: Knee ligament injuries often result in a premature end to a career in sports. The treatment after rupture of the anterior cruciate ligament (ACL) may be operative or conservative. In both cases, the goal is to reach the best functional level for the patient without risking new injuries or degenerative changes in the knee. Return to high level of athletic activity has been an indicator of treatment success. Rehabilitation is an important part of the treatment. Knowledge of healing processes and biomechanics in the knee joint after injury and reconstruction, together with physiological aspects on training effects is important for the construction of rehabilitation programmes. Current rehabilitation programmes use immediate training of range of motion. Weight bearing is encouraged within the first week after an ACL reconstruction. Commonly, the patients are allowed to return to light sporting activities such as running at 2–3 months after surgery and to contact sports, including cutting and jumping, after 6 months. In many cases, the decisions are empirically based and the rehabilitation programmes are adjusted to the time selected for returning to sports. In this article, some criteria that should be fulfilled in order to allow the patient to return to sports are presented. Surgery together with completed rehabilitation and sport-specific exercises should result in functional stability of the knee joint. In addition, adequate muscle strength and performance should be used as a critical criterion. Other factors, such as associated injuries and social and psychological hindrances may also influence the return to sports and must be taken into consideration, both during the rehabilitation and at the evaluation of the treatment.
TL;DR: The anti-CCP antibody assay has a similar diagnostic sensitivity to that of RF in early RA, but is better as a predictor of the disease course over 3 years, Although the mean serum level declines, anti- CCP antibody positivity remains essentially unaltered 3 years after diagnosis and start of antirheumatic treatment.
Abstract: Objectives: To evaluate the diagnostic sensitivity of antibodies to cyclic citrullinated peptide (CCP) in recent onset rheumatoid arthritis (RA) at diagnosis and 3 years later, and to evaluate anti-CCP antibody as a predictor of the disease course during 3 years. Methods: 242 patients with recent onset (⩽1 year) RA were followed up regularly during 3 years after inclusion in the Swedish multicentre study “TIRA” 1996–98. Anti-CCP antibodies were analysed by an enzyme immunoassay (EIA). Rheumatoid factors (RFs) were analysed by latex agglutination and two isotype-specific (IgM and IgA) EIAs. Disease activity was assessed by plasma CRP, ESR, 28 joint disease activity score, and the physician’s global assessment of disease activity. Functional ability was evaluated by the Health Assessment Questionnaire. Results: Overall, the diagnostic sensitivity of anti-CCP antibodies was 64% and the proportion of positive tests increased with the number of fulfilled classification criteria according to the American College of Rheumatology. The anti-CCP antibody results correlated with RF, but were better than RF as predictor of a more aggressive disease course. After 3 years 5/97 patients had changed anti-CCP status: 2 from negative to positive and 3 from positive to negative. The mean level of anti-CCP antibodies declined by 131 U/ml during the 3 year follow up (95% CI 34 to 228 U/ml). Conclusion: The anti-CCP antibody assay has a similar diagnostic sensitivity to that of RF in early RA, but is better as a predictor of the disease course over 3 years. Although the mean serum level declines, anti-CCP antibody positivity remains essentially unaltered 3 years after diagnosis and start of antirheumatic treatment.
TL;DR: This prospective study was performed to evaluate if cerebral monitoring using BIS to guide the conduction of anaesthesia could reduce this incidence significantly.
Abstract: Background: Explicit recall (ER) is evident in approximately 0.2% of patients given general anaesthesia including muscle relaxants. This prospective study was performed to evaluate if cerebral moni ...
TL;DR: This paper provides algorithms based on mixed-integer linear or quadratic programming which are guaranteed to converge to a global optimum of hybrid dynamical systems, and suggests a way of trading off between optimality and complexity by using a change detection approach.
TL;DR: A detailed analysis of the class of absolutely minimizing functions in Euclidean spaces and the relationship to the infinity Laplace equation is given in this article, where the authors also discuss the relationship between absolute minimization and the Laplace Equation.
Abstract: A detailed analysis of the class of absolutely minimizing functions in Euclidean spaces and the relationship to the infinity Laplace equation
TL;DR: This work suggests a framework for understanding the division of labor and cooperation among different inhibitory cell types in a recurrent cortical circuit in which three major subtypes of interneurons play distinct roles.
Abstract: A conspicuous feature of cortical organization is the wide diversity of inhibitory interneurons; their differential computational functions remain unclear. Here we propose a local cortical circuit in which three major subtypes of interneurons play distinct roles. In a model designed for spatial working memory, stimulus tuning of persistent activity arises from the concerted action of widespread inhibition mediated by perisoma-targeting (parvalbumin-containing) interneurons and localized disinhibition of pyramidal cells via interneuron-targeting (calretinin-containing) interneurons. Moreover, resistance against distracting stimuli (a fundamental property of working memory) is dynamically controlled by dendrite-targeting (calbindin-containing) interneurons. The experimental observation of inverted tuning curves of monkey prefrontal neurons recorded during working memory supports a key model prediction. This work suggests a framework for understanding the division of labor and cooperation among different inhibitory cell types in a recurrent cortical circuit.
TL;DR: This paper explores in this paper a set of notions of human dignity, which are introduced and characterized as a position on a value scale and further specified through its relations to the notions of right, respect and self-respect.
Abstract: As a part of a research project on Dignity and Older Europeans (Fifth Framework (Quality of Life) Programme) I explore in this paper a set of notions of human dignity. The general concept of dignity is introduced and characterized as a position on a value scale and it is further specified through its relations to the notions of right, respect and self-respect. I present four kinds of dignity and spell out their differences: the dignity of merit, the dignity of moral or existential stature, the dignity of identity and the universal human dignity (Menschenwurde). Menschenwurde pertains to all human beings to the same extent and cannot be lost as long as the persons exist. The dignity of merit depends on social rank and position. There are many species of this kind of dignity and it is very unevenly distributed among human beings. The dignity of merit exists in degrees and it can come and go. The dignity of moral stature is the result of the moral deeds of the subject; likewise it can be reduced or lost through his or her immoral deeds. This kind of dignity is tied to the idea of a dignified character and of dignity as a virtue. The dignity of moral stature is a dignity of degree and it is also unevenly distributed. The dignity of identity is tied to the integrity of the subject's body and mind, and in many instances, although not always, also dependent on the subject's self-image. This dignity can come and go as a result of the deeds of fellow human beings and also as a result of changes in the subject's body and mind.
TL;DR: It is concluded that sustained activation and loss of capacity to respond to a novel stressor could be a cause of the higher risk of illness and disease found among people with lower SES.
TL;DR: A statistical analysis of light propagation in media leads to new relationships between the K-M scattering S and absorbing K coefficients and the intrinsic scattering s and absorbing a coefficients of a material that indicate that the S and K coefficients depend non-linearly on both a and s.
Abstract: Using a statistical analysis of light propagation in media, we propose a revision to Kubelka-Munk (K-M) theory by taking into account the effect of scattering on the path length of light propagation (path variation). This leads to new relationships between the K-M scattering S and absorbing K coefficients and the intrinsic scattering s and absorbing a coefficients of a material that indicate that the S and K coefficients depend non-linearly on both a and s. The additivity law that bridges K-M S and K coefficients of a composite medium, such as dye-dispersed paper (dyed paper) and those of its material components (dye and paper), is also revised. It is further shown that experimental findings on dyed paper that the original K-M theory failed to explain can be clearly understood and accommodated by the new K-M theoretical framework (two-flux approach). Numerical simulations with the revised theory on model ink, paper, and dyed paper have been carried out.
TL;DR: Vertebral and hip fractures have a considerably greater and more prolonged impact on HRQOL than forearm and humerus fractures, and these differences should be taken into account when making priorities in health care programs.
Abstract: Objective: To estimate the impact of osteoporosis fractures on health-related quality of life (HRQOL) in postmenopausal women. Methods: To compare the impact on HRQOL of different osteoporotic fractures, 600 consecutive women 55–75 years old with a new fracture (inclusion fracture) were invited by mail. After exclusions by preset criteria (high-energy fractures, ongoing osteoporosis treatment, or unwillingness to participate), 303 women were included, 171 (56%) of whom had a forearm, 37 (12%) proximal humerus, 40 (13%) hip, and 55 (18%) vertebral fracture, respectively, and all were investigated and treated according to the current local consensus program for osteoporosis. In addition, HRQOL was evaluated by the SF-36 questionnaire and compared with local, age-matched reference material. Examinations were performed 82 days (median) after the fracture and 2 years later. Results: HRQOL was significantly reduced at baseline regarding all SF-36 domains after vertebral fractures and most after hip fractures, but only regarding some domains after forearm and humerus fracture. After 2 years, improvements had occurred after all types of fractures, and after forearm or humerus fracture, HRQOL was completely normalized in all domains. However, 2 years after hip fracture, HRQOL was still below normal regarding physical function, role-physical and social function, while after vertebral fracture, scores were still significantly lower for all domains, physical as well as mental. Patients with one or more previous fractures before the inclusion fracture had lower HRQOL at baseline and after 2 years, compared with those with no previous fracture. Patients with osteoporosis (T-score <−2.5 in hip or spine) had lower HRQOL than those with normal BMD. Conclusion: Vertebral and hip fractures have a considerably greater and more prolonged impact on HRQOL than forearm and humerus fractures. The number of fractures was inversely correlated to HRQOL. These differences should be taken into account when making priorities in health care programs.
TL;DR: In this paper, the authors show that customers will find it hard to distinguish between many products due to functional equivalency, and customers will therefore base their decisions on functional equivalence.
Abstract: Trends in product development today indicate that customers will find it hard to distinguish between many products due to functional equivalency. Customers will, therefore, base their decisions on ...
TL;DR: In this article, an empirical point of departure in an in-depth study of an R&D organization that was transformed into a strongly project-based organization was taken, as demonstrated in the analysis.
Abstract: This article takes an empirical point of departure in an in-depth study of an R&D organization that was transformed into a strongly project-based organization. As demonstrated in the analysis, its ...
TL;DR: In this article, the authors reviewed, classified and analyzed the recent contributions within the field of project management and presented a framework suitable for analyzing the developments made and the different perspectives launched, concluding that "project research" instead of Project management research might be a better concept for capturing the current state of the field.
TL;DR: In this article, the authors present an overview of the present status of quantitative tools, as a basis for further research and development, and compare five different tools for quantitative environmental assessment of the built environment.
07 Nov 2004
TL;DR: This paper addresses the problem of building scalable semantic overlay networks by separating a logical layer, the semantic overlay for managing and mapping data and metadata schemas, from a physical layer consisting of a structured peer-to-peer overlay network for efficient routing of messages.
Abstract: This paper addresses the problem of building scalable semantic overlay networks. Our approach follows the principle of data independence by separating a logical layer, the semantic overlay for managing and mapping data and metadata schemas, from a physical layer consisting of a structured peer-to-peer overlay network for efficient routing of messages. The physical layer is used to implement various functions at the logical layer, including attribute-based search, schema management and schema mapping management. The separation of a physical from a logical layer allows us to process logical operations in the semantic overlay using different physical execution strategies. In particular we identify iterative and recursive strategies for the traversal of semantic overlay networks as two important alternatives. At the logical layer we support semantic interoperability through schema inheritance and Semantic Gossiping. Thus our system provides a complete solution to the implementation of semantic overlay networks supporting both scalability and interoperability.