94 research outputs found
The Evolving Paradigm of Revascularization in Ischemic Cardiomyopathy: from Recovery of Systolic Function to Protection Against Future Ischemic Events
No full textPURPOSE OF REVIEW: We aim to reevaluate how the assessment of myocardial viability can guide optimal treatment strategies for patients with ischemic cardiomyopathy (ICM) based on a more contemporary understanding of the mechanism of benefit of revascularization. RECENT FINDINGS: The assessment of viability in left ventricular (LV) segments with diminished contraction has been proposed as key to predict the benefit of revascularization and, therefore, as a requisite for the selection of patients to undergo this form of treatment. However, data from prospective trials have diverged from earlier retrospective studies. Traditional binary viability assessment may oversimplify ICM\u27s complexity and the nuances of revascularization benefits. A conceptual shift from the traditional paradigm centered on the assessment of viability as a dichotomous variable to a more comprehensive approach encompassing a thorough understanding of ICM\u27s complex pathophysiology and the salutary effect of revascularization in the prevention of myocardial infarction and ventricular arrhythmias is required
Tracking JavaScript dependencies on the web
No full textThesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Title as it appears in MIT Commencement Exercises program, June 5, 2015: Dependency tracking. Cataloged from student-submitted PDF version of thesis.Includes bibliographical references (pages 49-50).Identifying the performance bottlenecks of Web pages is often the first step in reducing page load times. Existing models of Web pages (dependency graphs) ignore the dynamic interactions of JavaScript objects along these critical paths. Current dependency graphs solely include the dependencies that arise from a Web object triggering a new HTTP request. This thesis presents DepTracker, a tool that captures dynamically generated dependencies between JavaScript objects on a Web page. These JavaScript dependencies give a more accurate picture of the network and computational resources contributing to the critical path. DepTracker works in conjunction with an HTTP record-and-replay framework, Mahimahi [17], to track reads and writes to the JavaScript global namespace during actual page loads. We classify dependencies into three categories: write-read, read-write, and write-write. Preserving each of these dependencies maintains the consistency of JavaScript execution on Web pages. For each dependency tracked, DepTracker provides developers with relevant line numbers in the source code, variable names, and values that are assigned and read. This information is particularly useful to Web developers seeking to speed up accesses to their websites by reordering individual objects. We use DepTracker, along with Mahimahi, to expose dependencies on 10 popular Web pages. We find that each Web page includes dependencies between JavaScript objects that are not captured by existing dependency graphs. For our corpus of test sites, we find that graphs that include JavaScript dependencies tracked by DepTracker include 32% and 73% more edges than default dependency graphs, at the median and 95th percentile, respectively.by Ameesh Kumar Goyal.M. Eng
Cardiovascular Complications of Diabetes
No full textINTRODUCTION: Type 2 diabetes mellitus (T2DM) is the ninth leading cause of mortality globally, and the prevalence continues to rise. Among individuals with T2DM, over two-thirds of deaths are caused by the cardiovascular complications of diabetes. These complications include atherosclerosis, coronary artery disease, nephropathy, stroke, thromboembolism, peripheral vascular disease. They have been long studied, and there are several theories as to the pathophysiology of how diabetes leads to these complications. The least understood mechanism is the pathophysiology linking diabetes to heart failure.
AREAS COVERED: This review focuses on the mechanisms of how T2DM leads to the aforementioned complications, particularly highlighting the development of heart failure. An extensive literature review of novel therapeutic options targeting the cardiovascular effects of T2DM was completed and summarized in this review.
EXPERT OPINION: This review finds that most studies to date have focused on the atherosclerotic vascular complications of diabetes. The pathophysiology between T2DM and heart failure is even less understood. Currently therapies that aim to decrease the risk of heart failure in diabetes are sparse. More research is required in order to better understand the changes at a cellular level and subsequently help providers to choose therapeutics that better target cardiovascular complications
Rethinking the development process of mid-segment rental housing in the Netherlands: Exploratory research into the development process of mid-segment rental housing in the Netherlands.
No full textWith a shortage of approximately 315,000 homes, 4% of the existing stock, the Netherlands continues to face a significant and growing shortage of housing. This shortage is a result of various factors that either directly or indirectly have effect on the housing market. Of which some of the key factors are demographic developments such as population growth and changing household compositions; economic developments such as rising house prices, construction costs and income developments (affordability); political developments in regard to rising sustainability goals and changing regulations. These factors have a direct effect on all segments of the housing market, causing a shortage within all and predominantly for affordable of mid-priced rental homes with an estimated demand for 60,000 – 200,000 such homes over the next ten years. This demand or pressure on the mid-segment rental sector is a direct result of the inaccessibility to owner-occupied and social housing sector. As the house prices increase and the waitlist for social homes get longer the mid-segment housing market faces high demand and in turn pressurising both market parties and municipalities. Although there are developments within this segment and both parties are striving to ease the pressure on the market the supply of such homes is slow. Hence this research aims to increase the supply of mid-segment rental homes and contribute towards reducing the housing shortage in the Netherlands by hypothesising that improving the existing development process and policies within the mid-segment rental housing market would in turn improve the supply. Which brings us to the goal of the research to recommend measures/changes, that municipalities and market parties, could possibly make to improve the supply off mid-segment rental homes in the Netherlands. Given the regional characteristics of the housing market, this research adopts a case study method to analyse the development process and policies within different market types. Implying that the cases are market types and the phenomenon being explored, the development process of mid-segment homes. Learning from professionals in practice with the assistance of semi-structured interviews to first understand the existing process and policies, the problems encountered by them in the past and then collating recommendations from these actors to as how the process could be improved. Synthesising the information collected from the field research with theoretical findings to arrive at conclusions and in turn trying to answer the main research question: How can the development process of mid-segment rental housing, in the Netherlands, be improved to meet the rising demand in this segment of the housing market? On completing the research, through the interviews conducted it was found that the various actors along the process face challenges predominantly in the planning phase and challenges that arise from each other hence creating a rather uncertain environment to act in. Thus, reluctance in taking initiative and the shortage of mid-segment homes, although through this research an attempt was made to answer the main question by concluding that in order to improve the delivery of mid-segment homes it would essential to establish a well determined process, seek alternative land development approaches, allowing flexibility during negotiations and regulations, improving actor relationships, and developing policies that would not only regulate this segment but also stimulate market actors to develop mid-segment homes. Following these conclusions and aligning to the goal recommendations were made to the actors involved at an organisational and project level. Of the made recommendations the ones that stand out would be of municipalities supporting one another, involved actors form consortiums to share development risks, development of policies at a national level and finally establishing a trustful, transparent, certain, and supportive environment for each other.Architecture, Urbanism and Building Sciences | Management in the Built Environmen
Clinical Implication of Transvalvular Unloading With Venoarterial Extracorporeal Membrane Oxygenation Support in Acute Myocardial Infarction
No full text
Impella devices: a comprehensive review of their development, use, and impact on cardiogenic shock and high-risk percutaneous coronary intervention
No full textINTRODUCTION: Impella devices have emerged as a critical tool for temporary mechanical circulatory support (TMCS) in the management of cardiogenic shock (CS) and high-risk percutaneous coronary interventions (PCI). The purpose of this review is to examine the history of the different Impella devices, their hemodynamic profiles, and how the data supports their use. AREAS COVERED: This review covers the development and specifications of the Impella 2.5, Impella CP, Impella 5.0/Left Direct (LD), Impella RP, and Impella 5.5 devices. This review also covers the clinical trials that illuminate the Impella devices\u27 use in their appropriate clinical contexts. These studies examine the effectiveness of Impella devices and have begun to yield promising results, demonstrating improved survival rates when compared to the historically high mortality rates associated with CS. It is important to weigh the benefits of Impella devices in light of their contraindications. A literature search was conducted by searching the PubMed database for reviews, meta-analyses, and clinical trials pertinent to Impella devices. EXPERT OPINION: Impella devices are a crucial tool for management of patients undergoing high-risk PCI and those with CS. There is evidence that early Impella implantation is beneficial in the treatment of patients presenting with CS. Further randomized controlled trials are needed to better elucidate the benefits of Impella devices in various clinical settings
Catheter Thrombectomy for Basilar Artery Stroke Immediately After Insertion of Durable Left Ventricular Assist Device
No full textBackground: Acute ischemic stroke (AIS) following left ventricular assist device (LVAD) implantation is a serious complication associated with device morbidity. AIS development following LVAD placement typically presents between 6- and 24-months post implantation. Case/Results: We report a case of a 67-year-old male who initially presented with reduced ejection fraction and severe coronary vessel disease. Following coronary artery bypass graft surgery, the patient remained in a low output state necessitating placement of an LVAD device. Approximately 4.5 hours following LVAD implantation, a severe acute decrease in mental status revealed new development of ischemic stroke of the basilar artery, which was successfully treated in one pass with catheter endovascular thrombectomy. Conclusion: While embolic stroke management in these cases remains difficult as patients are usually anticoagulated, our case demonstrates the utilization of endovascular thrombectomy as a viable therapeutic option in the setting of an uncommon occurrence of embolic stroke in the hours following LVAD implantation
Emerging Modalities for Temporary Mechanical Circulatory Support in Cardiogenic Shock
No full textCardiogenic shock (CS) is a life-threatening medical condition that requires prompt recognition and treatment. The use of standardized CS criteria, such as the Society for Cardiovascular Angiography and Interventions criteria, can categorize patients and guide therapeutic strategies. Temporary mechanical circulatory support (MCS) devices have become valuable tools in the treatment of CS, as they can provide cardiovascular support as a bridge to recovery, cardiac surgery, or advanced therapies such as cardiac transplant or durable ventricular assist devices. The use of MCS should be tailored to each individual patient, focused on a stepwise escalation of circulatory support to support both end-organ perfusion and myocardial recovery. As newer MCS devices reduce myocardial oxygen demand without increasing ischemia, the possibility of recovery is optimized. In this review, we discuss the different modalities of MCS focusing on the mechanism of support and the advantages and disadvantages of each device
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