377 research outputs found
Semantics of UML 2.0 Activity Diagram for Business Modeling by Means of Virtual Machine
The paper proposes a more formalized definition of UML 2.0 Activity Diagram
semantics. A subset of activity diagram constructs relevant for business
process modeling is considered. The semantics definition is based on the
original token flow methodology, but a more constructive approach is used. The
Activity Diagram Virtual machine is defined by means of a metamodel, with
operations defined by a mix of pseudocode and OCL pre- and postconditions. A
formal procedure is described which builds the virtual machine for any activity
diagram. The relatively complicated original token movement rules in control
nodes and edges are combined into paths from an action to action. A new
approach is the use of different (push and pull) engines, which move tokens
along the paths. Pull engines are used for paths containing join nodes, where
the movement of several tokens must be coordinated. The proposed virtual
machine approach makes the activity semantics definition more transparent where
the token movement can be easily traced. However, the main benefit of the
approach is the possibility to use the defined virtual machine as a basis for
UML activity diagram based workflow or simulation engine.Comment: 12 pages, 7 figures, Proceedings of the conference "EDOC 2005", 19-23
September 200
Hot flashes in breast cancer survivors and an association with calcium supplement use
Gretchen Kimmick1,2, Gloria Broadwater2, Mara Vitolins31Medical Oncology, Wake Forest University School of Medicine, Winston-Salem; 2Cancer Center Biostatistics, Duke University Medical Center, Durham; 3Department of Epidemiology and Prevention, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USAAims: In breast cancer survivors, we aimed to describe the frequency of hot flashes and night sweats, frequency and type of treatment, and the association of hot flashes and use of calcium supplements.Methods: Charts of breast cancer survivors were reviewed for information about hot flashes, treatment for hot flashes, and calcium supplementation. Associations between variables were explored using the Chi-square test and Fisher’s Exact test.Results: Eighty-six charts were reviewed. Mean age of the women was 58 years and 79% were postmenopausal. Forty-two (49%) of women had hot flashes and 18 (21%) had night sweats. Thirty-one (36%) were treated for hot flashes. Treatment included selective serotonin reuptake inhibitors/serotonin-norepinephrine reuptake inhibitors (n = 19), clonidine (n = 7), Bellergal-S® (n = 8), sleep-aid (n = 7), and other (n = 5). Calcium supplementation was recorded in 31%. Of women with hot flashes, 44% took calcium supplements; of women without hot flashes, 18% took calcium supplements (Chi-square P = 0.02).Conclusion: Hot flashes were recorded in 49% of this group of primarily postmenopausal breast cancer survivors. Women with hot flashes were more likely to be taking calcium ­supplements. Further exploration of the association between hot flashes and calcium supplementation is warranted.Keywords: hot flashes, breast cancer, calcium supplementatio
Electrocardiographic repolarization-related variables as predictors of coronary heart disease death in the women's health initiative study.
BackgroundWe evaluated 25 repolarization-related ECG variables for the risk of coronary heart disease (CHD) death in 52 994 postmenopausal women from the Women's Health Initiative study.Methods and resultsHazard ratios from Cox regression were computed for subgroups of women with and without cardiovascular disease (CVD). During the average follow-up of 16.9 years, 941 CHD deaths occurred. Based on electrophysiological considerations, 2 sets of ECG variables with low correlations were considered as candidates for independent predictors of CHD death: Set 1, Ń²(Tp|Tref), the spatial angle between T peak (Tp) and normal T reference (Tref) vectors; Ń²(Tinit|Tterm), the angle between the initial and terminal T vectors; STJ depression in V6 and rate-adjusted QTp interval (QTpa); and Set 2, TaVR and TV1 amplitudes, heart rate, and QRS duration. Strong independent predictors with over 2-fold increased risk for CHD death in women with and without CVD were Ń²(Tp|Tref) >42Ā° from Set 1 and TaVR amplitude >-100 Ī¼V from Set 2. The risk for these CHD death predictors remained significant after multivariable adjustment for demographic/clinical factors. Other significant predictors for CHD death in fully adjusted risk models were Ń²(Tinit|Tterm) >30Ā°, TV1 >175 Ī¼V, and QRS duration >100 ms.ConclusionsŃ²(Tp|Tref) angle and TaVR amplitude are associated with CHD mortality in postmenopausal women. The use of these measures to identify high-risk women for further diagnostic evaluation or more intense preventive intervention warrants further study.Clinical trial registration urlhttp://www.clinicaltrials.gov. Unique identifier: NCT00000611
Specification and analysis of SOC systems using COWS: a finance case study
Service-oriented computing, an emerging paradigm for distributed computing based on the use of services, is calling for the development of tools and techniques to build safe and trustworthy systems, and to analyse their behaviour. Therefore many researchers have proposed to use process calculi, a cornerstone of current foundational research on specification and analysis of concurrent and distributed systems.
We illustrate this approach by focussing on COWS, a process calculus expressly designed for specifying and combining services, while modelling their dynamic behaviour. We present the calculus and one of the analysis techniques it enables, that is based on the temporal logic SocL and the associated model checker CMC. We demonstrate applicability of our tools by means of a large case study, from the financial domain, which is first specified in COWS, and then analysed by using SocL to express many significant properties and CMC to verify them
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