Update on hypertrophic cardiomyopathy and a guide to the guidelines

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiovascular disorder, affecting 1 in 500 individuals worldwide. Existing epidemiological studies might have underestimated the prevalence of HCM, however, owing to limited inclusion of individuals with early, incomplete phenotypic expression. Clinical manifestations of HCM include diastolic dysfunction, left ventricular outflow tract obstruction, ischaemia, atrial fibrillation, abnormal vascular responses and, in 5% of patients, progression to a 'burnt-out' phase characterized by systolic impairment. Disease-related mortality is most often attributable to sudden cardiac death, heart failure, and embolic stroke. The majority of individuals with HCM, however, have normal or near-normal life expectancy, owing in part to contemporary management strategies including family screening, risk stratification, thromboembolic prophylaxis, and implantation of cardioverter-defibrillators. The clinical guidelines for HCM issued by the ACC Foundation/AHA and the ESC facilitate evaluation and management of the disease. In this Review, we aim to assist clinicians in navigating the guidelines by highlighting important updates, current gaps in knowledge, differences in the recommendations, and challenges in implementing them, including aids and pitfalls in clinical and pathological evaluation. We also discuss the advances in genetics, imaging, and molecular research that will underpin future developments in diagnosis and therapy for HCM

Using inspection technology in object-oriented development projects

Software inspection is a proven approach for detecting and removing defects immediately after software documents are created. However, the advance of software technologies, processes, and methods, such as the widespread adoption of object-orientation, raises new problems regarding software quality assurance with inspections. These primarily relate to the question of how managers can organize a software inspection in object-oriented development projects with respect to the examined documentation and, once it has been organized, how developers can perform the defect detection activity in a systematic manner. This paper presents the architecture-centric strategy for inspection organization and the perspective-based reading technique to address the two problems. The integration of these approaches in the inspection approach allows practitioners to set up and run cost-effective inspections in their object-oriented development projects. To support this claim with quantitative findings, this paper presents the results of a controlled experiment to determine the feasibility and cost-effectiveness of the approaches when used for the inspection of UML-based design documents.L'inspection des logiciels est une m\ue9thode \ue9prouv\ue9e pour d\ue9tecter et \ue9liminer les d\ue9fauts imm\ue9diatement apr\ue8s la cr\ue9ation des documents logiciels. Les progr\ue8s des technologies, des processus et des m\ue9thodes logiciels, tels que l'adoption r\ue9pandue de l'orientation objets, cr\ue9ent toutefois de nouveaux probl\ue8mes en rapport avec les inspections de contr\uf4le de qualit\ue9 des logiciels. Ces probl\ue8mes ont surtout trait \ue0 la fa\ue7on dont les gestionnaires peuvent organiser une inspection du logiciel dans un projet de d\ue9veloppement orient\ue9 objets en ce qui concerne le document examin\ue9 et, une fois l'inspection organis\ue9e, \ue0 la fa\ue7on dont les concepteurs peuvent proc\ue9der \ue0 la d\ue9tection des d\ue9fauts de fa\ue7on syst\ue9matique. Ce m\ue9moire pr\ue9sente la strat\ue9gie centr\ue9e sur l'architecture pour l'organisation des inspections et la m\ue9thode de lecture \ue0 base de perspectives pour attaquer les deux probl\ue8mes. L'int\ue9gration de ces approches dans l'inspection permet aux ex\ue9cutants de monter et d'ex\ue9cuter des inspections \ue9conomiques dans leurs projets de d\ue9veloppement orient\ue9s objets. Pour appuyer cette affirmation avec des r\ue9sultats quantitatifs, ce m\ue9moire pr\ue9sente les r\ue9sultats d'une exp\ue9rience contr\uf4l\ue9e sur la faisabilit\ue9 et la rentabilit\ue9 de ces m\ue9thodes quand elles sont utilis\ue9es pour l'inspection d'avant-projets en langage UML.Peer reviewed: NoNRC publication: Ye

Investigating the effect of corpus construction on latent dirichlet allocation based feature location

The software maintenance community has adopted text retrieval techniques to aid program comprehension tasks, e.g., feature location --- the process of finding the source code entity or entities that implement a system feature. Latent Dirichlet Allocation (LDA) and latent semantic indexing (LSI) are two such text retrieval techniques. However, little work exists to inform the configuration of these text retrieval techniques for software maintenance tasks. This work investigates the impact of highly configurable preprocessing techniques on LDA based feature location. These decisions affect the composition and quality of the corpus and thus the accuracy of the text retrieval technique. Source code extraction is based on a researcher's understanding of source code use. We decompose source code into three distinct lexicons: identifiers, comments, and literals. Many researchers choose the aggregation of the lexicons; however, some choose specific subsets. This work finds that the chosen text source(s) does impact the accuracy of the LDA based FLT. Conventional wisdom holds that identifier splitting improves the performance of a text retrieval based FLT. However, the decision to retain or remove the original identifier is unexplored. This work finds that identifier splitting does impact the accuracy of the LDA based FLT, but retaining or removing the original identifier does not have a significant impact. Stop words, words with little semantic value, are often removed from natural language corpora. This work explores the impact of stop word removal on source code corpora. The observations prove that few stop word configurations are significantly different from one another --- even a null configuration is acceptable. The Porter stemming algorithm is a popular, light-weight, rule-based stemmer, often used in software maintenance preprocessing applications. We investigate the effects of two heavy stemmers, two light stemmers, four blended stemmers, and a null configuration. One light stemmer is morphological and the other stemmers are rule-based. The results indicate that no stemming algorithm significantly affects the performance of the FLT as compared to another stemming algorithm. We suggest basing preprocessing decisions on system structure and constraints. As such, these recommendations reduce the memory and/or processing time needed for LDA based feature location. (Published By University of Alabama Libraries

Combining information retrieval modules and structural information for source code bug localization and feature location

Bug localization and feature location in source code are software evolution tasks in which developers use information about a bug or feature present in a software system to locate the source code elements, such as classes or methods. These classes or methods must be modified either to correct the bug or implement a feature. Automating bug localization and feature location are necessary due to the size and complexity of modern software systems. Recently, researchers have developed static bug localization and feature location techniques using information retrieval techniques, such as latent semantic indexing (LSI), to model lexical information, such as identifiers and comments, from source code. This research presents a new technique, LSICG, which combines LSI modeling lexical information and call graphs to modeling structural information. The output is a list of methods ranked in descending order by likelihood of requiring modification to correct the bug or implement the feature under consideration. Three case studies including comparison of LSI and LSICG at method level and class level of granularity on 25 features in JavaHMO, 35 bugs in Rhino, 3 features and 6 bugs in jEdit demonstrate that The LSICG technique provides improved performance compared to LSI alone. (Published By University of Alabama Libraries