As tools for design get increasingly complex and powerful, it is increasingly important that their users have a solid grounding in what it is these tools do and how they do it. When these tools are software engineerin...
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ISBN:
(纸本)9781605584362
As tools for design get increasingly complex and powerful, it is increasingly important that their users have a solid grounding in what it is these tools do and how they do it. When these tools are software engineering tools, we can assume that their users have formal training in computing. However, when the tools are for designing art or multimedia objects, the artists using the tools typically don't have much background in the computing technology they are using. While interdisciplinary design teams can work around the shortcomings of individual team members, they might be more effective teams if they shared a common language and understanding of certain key aspects of the design process. At the University of Washington we have begun a project to study the use of the theory of problem solving as shared knowledge by design teams engaged in creating of multimedia games. The theory we used is derived from early work in artificial intelligence. The concepts of state space, search, operators and evaluation functions are key components of the shared knowledge. The theory is embodied in a software system called T-STAR (Transparent STate-spaces search ARchitecture) which supports a collaborative interface for problem-solving. A key question for the project is "to what extent will interdisciplinary design teams adopt and exploit the theory of problem solving when given an opportunity to do so?"
The fast emergent and continuously evolving areas of the Semantic Web and Knowledge Management make the incorporation of ontology engineering tasks in knowledge-empowered organizations and in the World Wide Web more t...
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The fast emergent and continuously evolving areas of the Semantic Web and Knowledge Management make the incorporation of ontology engineering tasks in knowledge-empowered organizations and in the World Wide Web more than necessary. In such environments, the development and evolution of ontologies must be seen as a dynamic process that has to be supported through the entire ontology life cycle, resulting to living ontologies. The aim of this paper is to present the human-centered Ontology Engineering Methodology (HCOME) for the development and evaluation of living ontologies in the context of communities of knowledge workers. The methodology aims to empower knowledge workers to continuously manage their formal conceptualizations in their day-to-day activities and shape their information space by being actively involved in the ontology life cycle. The paper also demonstrates the humancentered ONtology Engineering Environment, HCONE, which can effectively support this methodology.
A framework for the development of a decision support system (DSS) that exhibits uncommonly transparent rule-based inference logic is introduced. A DSS is constructed by marrying a statistically based fuzzy inference ...
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A framework for the development of a decision support system (DSS) that exhibits uncommonly transparent rule-based inference logic is introduced. A DSS is constructed by marrying a statistically based fuzzy inference system (FIS) with a user interface, allowing drill-down exploration of the underlying statistical support, providing transparent access to both the rule-based inference as well as the underlying statistical basis for the rules. The FIS is constructed through a "Pattern Discovery" based analysis of training data. Such an analysis yields a rule base characterized by simple explanations for any rule or data division in the extracted knowledge base. The reliability of a fuzzy inference is well predicted by a confidence measure that determines the probability of a correct suggestion by examination of values produced within the inference calculation. The combination of these components provides a means of constructing decision support systems that exhibit a degree of transparency beyond that commonly observed in supervised-learning-based methods. A prototype DSS is analyzed in terms of its workflow and usability, outlining the insight derived through use of the framework. This is demonstrated by considering a simple synthetic data example and a more interesting real-world example application with the goal of characterizing patients with respect to risk of heart disease. Specific input data samples and corresponding output suggestions created by the system are presented and discussed. The means by which the suggestions made by the system may be used in a larger decision context is evaluated.
Liver transplantation (OLT) is a treatment for hepatocellular carcinoma (HCC) superimposed on cirrhosis provided that the disease meets defined criteria. The aim of the study was to evaluate our experience with respec...
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Liver transplantation (OLT) is a treatment for hepatocellular carcinoma (HCC) superimposed on cirrhosis provided that the disease meets defined criteria. The aim of the study was to evaluate our experience with respect to clinical and pathological staging and long-term results. From 1996 to 2005, 50 patients underwent OLT for HCC including 43 men (86%) and seven women (14%) of median age 57 years (range 37 to 67). All patients fulfilled the Milan criteria. The HCC diagnosis was based on preoperative imaging and alpha-fetoprotein levels;no tumor biopsy was performed. Upon histological examination of the resected specimens, we discovered 6 (12%) incidentalomas and 8 (16%) cases of no HCC. Finally we had 42 "true" HCC. Twenty-six patients (52%) have been downstaged and 10 (20%) upstaged by preoperative imaging;15% were pT1, 45% were pT2, 27% pT3, and 13% pT4a. Twenty-six percent of cases exceeded the Milan criteria. One patient (pT4a) with microvascular invasion died of pulmonary metastases at 14 months after transplantation. No HCC recurrences within the liver have been encountered at a median follow-up of 20 months (range 0 to 80 months). Overall the estimated 1-, 3-, and 5-year survival rates were 83%, 77%, and 72%, respectively. One-, 3-, and 5-year estimated survival rates were 87%, 75%, and 75% for pT1, and pT2, and 75%, 67%, and 67% for pT3 and pT4a, respectively (P =.99). Based on our experience OLT for HCC has long-term results comparable to those without HCC despite the presence of a significant number of cases exceeding the Milan criteria upon pathological staging.
Hepatocellular carcinoma (HCC) represents the sixth leading cancer and the third most common cause of death from cancer worldwide. There is no firstline option for patients with advanced HCC (vascular invasion, extrah...
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Hepatocellular carcinoma (HCC) represents the sixth leading cancer and the third most common cause of death from cancer worldwide. There is no firstline option for patients with advanced HCC (vascular invasion, extrahepatic spread, or cancer-related symptoms). Systemic doxorubicin provides partial responses in 10% of cases, without proven survival advantages, and well-known treatment-related complications. Several other treatments, such as immunotherapy, internal radiation, tamoxifen, or anti-androgen agents, have not shown any relevant anti-tumoral effect or survival benefit . Experimentally, estrogens are involved in stimulating hepa-tocyte proliferation in vitro and may act as liver tumor inducers or promoters in vivo. Inefficacy of anti-estrogen tamoxifen however, could be partly attributable to the presence of variant estrogen receptor (ER) forms , or to alternative, non-recep-torial mechanisms potentially involved in growth regulation of both normal and cancer human liver cells by estrogen . By assuming that estrogen plays a role in hepatoma cell growth through non-receptor pathways, we can think of a strategy as reducing estrogen concentration in tumor tissue through aromatase inhibitors that deplete estrogen by inhibiting aromatase, the enzyme that synthesizes estrogen from androgens. One study has investigated the activity and expression of aromatase enzyme in non-tumoral, cirrhotic, and malignant human liver tissues and cells using both chromatographic and reverse transcription) (RT)-PCR analyses. They reported that human HCC tissues showed elevated aromatase activity, with increased estrogen formation rates, as opposed to non-tumoral hepatic tissues . Therefore, aromatase inhibitors may be considered in the management of advanced HCC.
The work-centered support system approach to human-centered computing focuses on analyzing and supporting the multiple facets of work. The WCSS for global weather management developed to support weather forecasting an...
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The work-centered support system approach to human-centered computing focuses on analyzing and supporting the multiple facets of work. The WCSS for global weather management developed to support weather forecasting and monitoring in an airlift service organization, exemplifies this approach. A hallmark of human-centered computing (HCC) is its focus on domain practitioners and their field of practice. human-centered design depends on a deep analysis of a field\'s cognitive and collaborative demands and how people work individually, in groups, and in organizations to meet those demands. The objective is to leverage what we know about human cognitive and collaborative processes to create systems that optimize the affordances (direct perception of meanings) and effectivities (knowledge-driven actions) for humans. The WCSS paradigm offers an approach for incorporating software agent technology in a manner that helps the user keep the head in the work and reduces the possibility that software agent states or actions surprise the user.
Many healthcare technology projects fail due to the lack of consideration of human issues, such as workflow, organizational change, and usability, during the design and implementation stages of a project's develop...
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Many healthcare technology projects fail due to the lack of consideration of human issues, such as workflow, organizational change, and usability, during the design and implementation stages of a project's development process. Even when human issues are considered, the consideration is typically on designing better user interfaces. We argue that human-centered computing goes beyond a better user interface: it should include considerations of users, functions and tasks that are fundamental to human-centered computing. From this perspective, we integrated a previously developed human-centered methodology with a Project Design Lifecycle, and we applied this integration in the design of a complex distributed knowledge management system for the Biomedical Engineer (BME) domain in the Mission Control Center at NASA Johnson Space Center. We analyzed this complex system, identified its problems, generated systems requirements, and provided specifications of a replacement prototype for effective organizational memory and knowledge management. We demonstrated the value provided by our human-centered approach and described the unique properties, structures, and processes discovered using this methodology and how they contributed in the design of the prototype. (C) 2004 Elsevier Inc. All rights reserved.
Hepatocellular carcinoma (HCC) is one of the most common malignant tumours worldwide. The major etiologies and risk factors for HCC development are well defined and some of the multiple steps involved in hepatocarcino...
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Hepatocellular carcinoma (HCC) is one of the most common malignant tumours worldwide. The major etiologies and risk factors for HCC development are well defined and some of the multiple steps involved in hepatocarcinogeresis have been elucidated in recent years. Despite these scientific advances and the implementation of measures for early HCC detection in patients at risk, patient survival has not improved during the last three decades. This is due in part to the advanced stage of the disease at the time of clinical presentation, in part due to the limited therapeutic options. These fall into four main categories: (1) surgical interventions, incl. tumour resection and liver transplantation, (2) percutaneous interventions, incl. ethanol injection and radiofrequency thermal ablation, (3) transarterial interventions, incl. embolisation and chemoembolisation and (4) drugs as well as gene and immune therapies. These therapeutic strategies have been evaluated in part in randomised controlled clinical trials that are the basis for therapeutic recommendations. While surgery and percutaneous as well as transarterial interventions are effective in patients with limited disease (1-3 lesions, < 5 cm in diameter) and compensated underlying liver disease (cirrhosis Child A), at the time of diagnosis more than 80% patients present with multicentric HCC and advanced liver disease or comorbidities that restrict the therapeutic measures to best supportive care. In order to reduce morbidity and mortality from HCC, therefore, early diagnosis and the development of novel systemic therapies for advanced disease, incl. drugs, gene and immune therapies as well as primary HCC prevention are of paramount importance. Further, secondary HCC prevention after successful therapeutic interventions needs to be improved in order to make an impact on the survival of patients with HCC. New technologies, including gene expression profiling and proteomic analyses, should further elucidate the molecular
Background: Although chronic infection with hepatitis B virus (HBV) has been established as a cause of hepatocellular carcinoma (HCC), the roles of viral load and HBV genotype remain unclear. Methods: From 1988 throug...
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Background: Although chronic infection with hepatitis B virus (HBV) has been established as a cause of hepatocellular carcinoma (HCC), the roles of viral load and HBV genotype remain unclear. Methods: From 1988 through 1992, baseline blood samples were collected from 4841 Taiwanese men who were HBV carriers but had not been diagnosed with HCC. We used real-time polymerase chain reaction assays of plasma DNA samples to quantify HBV DNA levels (a measure of viral load) and determine HBV genotypes for 154 case patients who were diagnosed with HCC during 14 years of follow-up and 316 control subjects. Unconditional logistic regression was used to assess odds ratios (ORs) of HCC for HBV-related factors. All statistical tests were two-sided. Results: The risk of HCC increased with increasing HBV viral load (adjusted OR for the highest versus the lowest quintile of HBV DNA copies/mL = 7.26, 95% confidence interval [CI] = 3.54 to 14.89;P-trend < .001). Genotype C HBV was associated with an increased risk of HCC compared with other HBV genotypes (adjusted OR = 5.11, 95% CI = 3.20 to 8.18). Both viral load and genotype were positively associated with HCC within 10-year age categories among subjects aged 30 years old to older than 60 years. Genotype C HBV was associated with increased viral load, and associations of HBV genotype and viral load with HCC risk were additive. The adjusted OR of HCC for those carrying genotype C HBV and with viral load in the highest quintile was 26.49 (95% CI = 10.41 to 67.42) compared with HBV carriers with other HBV genotypes and viral load in the lowest two quintiles. Conclusions: Measurements of HBV viral load and genotype may help to define which male HBV carriers aged 30 years or older are at high risk for HCC.
Microscopic tumor cell dissemination may be a more important factor in the recurrence of hepatocellular carcinoma (HCC) after liver transplantation, probably because of posttransplant immnosuppression. The presence of...
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Microscopic tumor cell dissemination may be a more important factor in the recurrence of hepatocellular carcinoma (HCC) after liver transplantation, probably because of posttransplant immnosuppression. The presence of microvascular tumor embolism was undetermined as a factor for HCC recurrence after orthotopic liver transplantation (OLT). This study evaluated whether microvascular tumor embolism affects recurrence-free survival and correlates with other clinicopathologic factors after OLT among patients with HCC. From September 1996 to June 2003,72 OLTs for HCC were enrolled in this study. Median follow-up was 22.8 months. Among 41 patients without microvascular tumor embolism, 1-year, 2-year, and 5-year recurrence-free survival rates were all 97.6%, while these rates were 77.3%, 68.2%, and 59.7%, respectively, for 31 patients (43.1%) with microvascular tumor embolism (P = .0006). The 5-year recurrence-free survival rate showed significant differences for a pT2 tumor (P = .0073), for maximal tumor size < 3 cm (P = .0328), for >= 5 cm solitary tumor (P = .0095), and for the presence of a tumor capsule (P = .0012), within the Milan criteria (P = .0376). At multivariate analysis, significant independent predictors for HCC recurrence were microvascular tumor embolism and histopathologic grade. In conclusion, microvascular tumor embolism is an independent predictor of HCC recurrence after liver transplantation. Although OLT is a safe and effective treatment for HCC within the Milan criteria, the presence of microvascular tumor embolism at pathologic examination can predict its recurrence. In these cases, the feasibility of immunosuppressive therapy or adjuvant chemotherapy must be considered to prevent tumor recurrence.
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