From informal requirements to a running program: A case study in algebraic specification and transformational programming

AbstractAlgebraic specification and transformational programming have been advocated as new approaches to the development of software, in order to solve some of the technical problems in software engineering such as “early validation”, correctness of implementations, re-usability of software, or re-usability of software design. By means of a nontrivial example, viz an interactive text editor, we demonstrate that the combined use of these approaches allows to bridge the gap between verbally stated requirements and a running program, even for non-toy, realistic problems

Inelastic Compression is Effective Over Time in Spite of Significant Pressure Drop

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Bandages or Double Stockings for the Initial Therapy of Venous Oedema? A Randomized, Controlled Pilot Study

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High Compression Pressure over the Calf is More Effective than Graduated Compression in Enhancing Venous Pump Function

AbstractBackgroundGraduated compression is routinely employed as standard therapy for chronic venous insufficiency.AimThe study aims to compare the haemodynamic efficiency of a multi-component graduated compression bandage (GCB) versus a negative graduated compression bandage (NGCB) applied with higher pressure over the calf.MethodsIn 20 patients, all affected by greater saphenous vein (GSV) incompetence and candidates for surgery (Clinical, etiologic, anatomic and pathophysiologic data, CEAP C2-C5), the ejection fraction of the venous calf pump was measured using a plethysmographic method during a standardised walking test without compression, with GCB and NGCB, all composed of the same short-stretch material. Sub-bandage pressures were measured simultaneously over the distal leg and over the calf.ResultsNGCBs with median pressures higher at the calf (62 mmHg) than at the distal leg (50 mmHg) achieved a significantly higher increase of ejection fraction (median +157%) compared with GCB, (+115%) with a distal pressure of 54 mmHg and a calf pressure of 28 mmHg (P < 0.001).ConclusionsPatients with severe venous incompetence have a greater haemodynamic benefit from NGCB, especially during standing and walking, than from GCB

Compression Stockings with a Negative Pressure Gradient Have a More Pronounced Effect on Venous Pumping Function than Graduated Elastic Compression Stockings

AbstractObjectivesTo measure the effect on the venous pumping function of a stocking providing a negative pressure gradient with higher pressures over the calf in comparison to a conventional graduated elastic compression stocking (GECS) in patients with advanced venous insufficiency.DesignExperimental study.Material30 patients with severe superficial chronic venous insufficiency were enrolled. Two elastic stocking designs exerting a pressure at ankle between 15 and 25 mm Hg were compared; a conventional GECS and a stocking exerting a higher pressure over the calf than over the ankle producing a “progressive” increase in compression (PECS).Methodthe venous calf pumping function was assessed by measuring the ejection fraction (EF) from the lower leg by a plethysmographic method during a standardised exercise. Interface pressure of the 2 compression devices was simultaneously recorded both at B1 = 12 cm above ankle, C = just above widest part of calf.ResultsThe mean increase of EF produced by PECS was +75% (95 CI 48,7-101,3) compared with +32% (95%CI 16,8-48,6) with GECS (P < 0.001). There was a significant correlation between EF and the stocking pressure measured at calf level during standing and walking.ConclusionStockings exerting a higher pressure on the calf than on the ankle show a greater efficacy in increasing the venous ejection fraction from the leg

The use of compression stockings for venous disorders in Brazil

Objective: the aim of this study was to analyse the medical indication and the use of elastic compression stockings, and to assess patient adherence to treatment in different regions of Brazil.Method: the prescription and clinical indication of elastic stockings were evaluated in a prospective, descriptive, cross-sectional, multicentre study for a population of private patients. in 2009, 3414 patients from 123 treatment centres in southern, south-eastern and north-eastern Brazil were evaluated using a questionnaire. the following variables were analysed: sociodemographic (gender, age, occupation and education), lifestyle (physical activity and time spent standing); classification of venous disease (CEAP [clinical, aetiological, anatomical and pathophysiological] classification - clinical criteria), indications for prescription, consumer behaviour (strength, acquisition and use of stockings) and criteria of satisfaction (improvement, duration of use, adherence). the effects of compression therapy were assessed at a follow-up visit approximately 30 days after starting treatment with the following items being assessed: complaints about pain, discomfort, burning sensation and oedema of the leg while using elastic stockings. Multivariate analysis was used to compare data with an alpha error of 5% (P value < 0.05) being considered acceptable.Results: the average age increased with the severity of chronic venous insufficiency; the main indications used by physicians were leg pain and discomfort; 89.3% of patients bought stockings and thus started treatment with more than 90% of these reporting improvements in symptoms.Conclusion: Elastic stockings are available to the Brazilian population, look acceptable at the time of purchase and provide good results; however, some limitations regarding their use need to be addressed.Univ Estadual Campinas, UNICAMP, Serv Peripheral Vasc Dis, Campinas, BrazilMed Sch Sao Jose do Rio Preto FAMERP, Dept Cardiol & Cardiovasc Surg, Sao Jose do Rio Preto, BrazilUniversidade Federal de São Paulo, UNIFESP, Discipline Vasc Surg, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP, Discipline Vasc Surg, São Paulo, BrazilWeb of Scienc

Appraisal of the information content of the C classes of CEAP clinical classification of chronic venous disorders: A multicenter evaluation of 872 patients

AbstractObjective: Clinical classifications attempt to summarize a large amount of information in a few indices. CEAP is the most comprehensive and widely used classification of chronic venous disorders. The objective was to evaluate, in a routine clinical setting, the information associated with each CEAP clinical class and their ascending severity and additivity. Methods: This work was a multicenter evaluation of newly designed software dedicated to the management of venous diseases. Forty-nine angiologists from nine European countries entered a total of 872 full records of unselected patients. The data were analyzed to evaluate the informational value of each of the clinical classes and to test their ascending severity and additivity, with monovariate and multivariate statistical techniques with SPSS/PC software on the database of the 872 right lower limbs. Results: The series consisted of 700 women (80.3%) and 172 men, aged 18 to 100 years (median, 53 years). The ascending severity of the classes was shown with the statistical association of higher severity C classes with the age of the patient, a history of previous deep vein thrombosis, the diameter class of the most dilated varicose vein, venous symptoms, and the presence of a corona phlebectatica. The additivity, as measured with the Cronbach α coefficient analysis, was satisfactory in highest classes but poorer within the first three classes, and factor analysis of correspondences showed the heterogeneity of the variables that make the classification. Conclusion: The information summarized with the CEAP clinical classes shows a good ascending severity but a poorer additivity. These limitations seem to be related to the heterogeneity of the information content, which suggests some refinements of this basic tool for clinical research in the field of chronic venous disorders. (J Vasc Surg 2003;37:827-33.

USTOPIA REQUIREMENTS THOUGHTS ON A USER-FRIENDLY SYSTEM FOR TRANSFORMATION OF PROGRAMS IN ABSTRACTO

Transformational programming is a program development method which is usually applied using 'pen and paper'. Since this requires a lot of clerical work (copying expressions, con- sistent substitution) which is tiresome and prone to error, some form of machine support is desirable. In this paper a number of systems are described that have already been built to this aim. Some of their shortcomings and limitations are identified. Based on experience with program transformation and transformation systems, a long list of features is given that would be useful in an 'utopian' transformation system. This list is presented using an orthogonal division of the problem area. A number of problems with the realisation of some aspects of our 'utopian' system are identified, and some areas for further research are indicated

An investigation to assess ankle mobility in healthy individuals from the application of multi-component compression bandages and compression hosiery

Background An investigation was undertaken to compare the effect of multi-component compression bandages and compression hosiery kits on individuals’ range of ankle motion whilst wearing typical and medical footwear, and barefoot. Methods A convenience sample of 30 healthy individuals recruited from the staff and student population at the University of Huddersfield, UK. Plantarflexion/dorsiflexion range of ankle motion (ROAM) was measured in participants over 6 steps in every combination of typical, medical and no footwear; and multi-component bandages, compression hosiery and no garments. Results Controlling for age, gender and garments, the use of typical footwear was associated with a mean increase in ROAM of 2.54° at best estimate compared with barefoot; the use of medical footwear was associated with a mean decrease in ROAM of 1.12° at best estimate compared with barefoot. Controlling for age, gender and footwear, the use of bandaging was associated with a mean decrease in ROAM of 2.51° at best estimate compared with no garments. Controlling for age, gender and footwear, the use of hosiery was not associated with a significant change in ROAM compared with no garments. Conclusions Bandages appear to restrict ROAM more than hosiery when used in conjunction with a variety of footwear types

Guidelines for Clinical Studies with Compression Devices in Patients with Venous Disorders of the Lower Limb

Digitalitzat per Artypla