A decision making framework for cruise ship design

Thesis (S.M. in Ocean Systems Management and S.M. in Naval Architecture and Marine Engineering)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references (p. 91-97).This thesis develops a new decision making framework for initial cruise ship design. Through review of effectiveness analysis and multi-criteria decision making, a uniform philosophy is created to articulate a framework that would enable a designer to more accurately assess what design alternatives are more important than others and how their changes affect the overall system being designed. Through a brief historical account, top-level Measures of Merit are developed and used with the framework and then applied to a requirements and effectiveness case study on initial concept development of a cruise ship. This is performed using Response Surface Methods to enable the user to visualize the design space as well as interact with it; the results and methods to visualize the design space are discussed. Finally, a Unified Tradeoff Environment is discussed, a framework that pools the aforementioned requirements and effectiveness analysis with design and technology forecasting to enable the user to make better informed requirements derivation and design selection.by George P. Katsoufis.S.M.in Ocean Systems Management and S.M.in Naval Architecture and Marine Engineerin

Prevalence of Clinical and Neuroimaging Markers in Cerebral Amyloid Angiopathy: A Systematic Review and Meta-Analysis

BACKGROUND: Limited data exist regarding the prevalence of clinical and neuroimaging manifestations among patients diagnosed with cerebral amyloid angiopathy (CAA). We sought to determine the prevalence of clinical phenotypes and radiological markers in patients with CAA. METHODS: Systematic review and meta-analysis of studies including patients with CAA was conducted to primarily assess the prevalence of clinical phenotypes and neuroimaging markers as available in the included studies. Sensitivity analyses were performed based on the (1) retrospective or prospective study design and (2) probable or unspecified CAA status. We pooled the prevalence rates using random-effects models and assessed the heterogeneity using the Cochran Q and I2 statistics. RESULTS: We identified 12 prospective and 34 retrospective studies including 7159 patients with CAA. The pooled prevalence rates were cerebral microbleeds (52% [95% CI, 43%-60%]; I2=93%), cortical superficial siderosis (49% [95% CI, 38%-59%]; I2=95%), dementia or mild cognitive impairment (50% [95% CI, 35%-65%]; I2=97%), intracerebral hemorrhage (ICH; 44% [95% CI, 27%-61%]; I2=98%), transient focal neurological episodes (48%; 10 studies [95% CI, 29%-67%]; I2=97%), lacunar infarcts (30% [95% CI, 25%-36%]; I2=78%), high grades of perivascular spaces located in centrum semiovale (56% [95% CI, 44%-67%]; I2=88%) and basal ganglia (21% [95% CI, 2%-51%]; I2=98%), and white matter hyperintensities with moderate or severe Fazekas score (53% [95% CI, 40%-65%]; I2=91%). The only neuroimaging marker that was associated with higher odds of recurrent ICH was cortical superficial siderosis (odds ratio, 1.57 [95% CI, 1.01-2.46]; I2=47%). Sensitivity analyses demonstrated a higher prevalence of ICH (53% versus 16%; P=0.03) and transient focal neurological episodes (57% versus 17%; P=0.03) among retrospective studies compared with prospective studies. No difference was documented between the prevalence rates based on the CAA status. CONCLUSIONS: Approximately one-half of hospital-based cohort of CAA patients was observed to have cerebral microbleeds, cortical superficial siderosis, mild cognitive impairment, dementia, ICH, or transient focal neurological episodes. Cortical superficial siderosis was the only neuroimaging marker that was associated with higher odds of ICH recurrence. Future population-based studies among well-defined CAA cohorts are warranted to corroborate our findings

Performance and Safety of EUS Ablation Techniques for Pancreatic Cystic Lesions: A Systematic Review and Meta-Analysis

Background: Pancreatic cystic lesions (PCL) represent an increasingly diagnosed condition with significant burden to patients’ lives and medical resources. Endoscopic ultrasound (EUS) ablation techniques have been utilized to treat focal pancreatic lesions. This systematic review with meta-analysis aims to assess the efficacy of EUS ablation on PCL in terms of complete or partial response and safety. Methods: A systematic search in Medline, Cochrane and Scopus databases was performed in April 2023 for studies assessing the performance of the various EUS ablation techniques. The primary outcome was complete cyst resolution, defined as cyst disappearance in follow-up imaging. Secondary outcomes included partial resolution (reduction in PCL size), and adverse events rate. A subgroup analysis was planned to evaluate the impact of the available ablation techniques (ethanol, ethanol/paclitaxel, radiofrequency ablation (RFA), and lauromacrogol) on the results. Meta-analyses using a random effects model were conducted and the results were reported as percentages with 95% confidence intervals (95%CI). Results: Fifteen studies (840 patients) were eligible for analysis. Complete cyst resolution after EUS ablation was achieved in 44% of cases (95%CI: 31–57; 352/767; I2 = 93.7%), and the respective partial response rate was 30% (95%CI: 20–39; 206/767; I2 = 86.1%). Adverse events were recorded in 14% (95%CI: 8–20; 164/840; I2 = 87.2%) of cases, rated as mild in 10% (95%CI: 5–15; 128/840; I2 = 86.7%), and severe in 4% (95%CI: 3–5; 36/840; I2 = 0%). The subgroup analysis for the primary outcome revealed rates of 70% (95%CI: 64–76; I2 = 42.3%) for ethanol/paclitaxel, 44% (95%CI: 33–54; I2= 0%) for lauromacrogol, 32% (95%CI: 27–36; I2 = 88.4%) for ethanol, and 13% (95%CI: 4–22; I2 = 95.8%) for RFA. Considering adverse events, the ethanol-based subgroup rated the highest percentage (16%; 95%CI: 13–20; I2 = 91.0%). Conclusion: EUS ablation of pancreatic cysts provides acceptable rates of complete resolution and a low incidence of severe adverse events, with chemoablative agents yielding higher performance rates

Cerebrospinal fluid α-synuclein species in cognitive and movements disorders

Total CSF α-synuclein (t-α-syn), phosphorylated α-syn (pS129-α-syn) and α-syn oligomers (o-α-syn) have been studied as candidate biomarkers for synucleinopathies, with suboptimal specificity and sensitivity in the differentiation from healthy controls. Studies of α-syn species in patients with other underlying pathologies are lacking. The aim of this study was to investigate possible alterations in CSF α-syn species in a cohort of patients with diverse underlying pathologies. A total of 135 patients were included, comprising Parkinson’s disease (PD; n = 13), multiple system atrophy (MSA; n = 9), progressive supranuclear palsy (PSP; n = 13), corticobasal degeneration (CBD; n = 9), Alzheimer’s disease (AD; n = 51), frontotemporal degeneration (FTD; n = 26) and vascular dementia patients (VD; n = 14). PD patients exhibited higher pS129-α-syn/α-syn ratios compared to FTD (p = 0.045), after exclusion of samples with CSF blood contamination. When comparing movement disorders (i.e., MSA vs. PD vs. PSP vs. CBD), MSA patients had lower α-syn levels compared to CBD (p = 0.024). Patients with a synucleinopathy (PD and MSA) exhibited lower t-α-syn levels (p = 0.002; cut-off value: ≤865 pg/mL; sensitivity: 95%, specificity: 69%) and higher pS129-/t-α-syn ratios (p = 0.020; cut-off value: ≥0.122; sensitivity: 71%, specificity: 77%) compared to patients with tauopathies (PSP and CBD). There are no significant α-syn species alterations in non-synucleinopathies.This study was supported by Strat-up Funding to OE from Qatar Biomedical Research Institute (SF 2007–007) and Qatar National Research Fund (NPRPNo.: 8–517–3-112)

A Powerful Paradigm for Cardiovascular Risk Stratification Using Multiclass, Multi-Label, and Ensemble-Based Machine Learning Paradigms: A Narrative Review

Background and Motivation: Cardiovascular disease (CVD) causes the highest mortality globally. With escalating healthcare costs, early non-invasive CVD risk assessment is vital. Conventional methods have shown poor performance compared to more recent and fast-evolving Artificial Intelligence (AI) methods. The proposed study reviews the three most recent paradigms for CVD risk assessment, namely multiclass, multi-label, and ensemble-based methods in (i) office-based and (ii) stress-test laboratories. Methods: A total of 265 CVD-based studies were selected using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) model. Due to its popularity and recent development, the study analyzed the above three paradigms using machine learning (ML) frameworks. We review comprehensively these three methods using attributes, such as architecture, applications, pro-and-cons, scientific validation, clinical evaluation, and AI risk-of-bias (RoB) in the CVD framework. These ML techniques were then extended under mobile and cloud-based infrastructure. Findings: Most popular biomarkers used were office-based, laboratory-based, image-based phenotypes, and medication usage. Surrogate carotid scanning for coronary artery risk prediction had shown promising results. Ground truth (GT) selection for AI-based training along with scientific and clinical validation is very important for CVD stratification to avoid RoB. It was observed that the most popular classification paradigm is multiclass followed by the ensemble, and multi-label. The use of deep learning techniques in CVD risk stratification is in a very early stage of development. Mobile and cloud-based AI technologies are more likely to be the future. Conclusions: AI-based methods for CVD risk assessment are most promising and successful. Choice of GT is most vital in AI-based models to prevent the RoB. The amalgamation of image-based strategies with conventional risk factors provides the highest stability when using the three CVD paradigms in non-cloud and cloud-based frameworks

Headache during airplane travel (“airplane headache”): first case in Greece

Headache related to airplane flights is rare. We describe a 37-year-old female patient with multiple intense, jabbing headache episodes over the last 3 years that occur exclusively during airplane flights. The pain manifests during take-off and landing, and is located always in the left retro-orbital and frontotemporal area. It is occasionally accompanied by dizziness, but no additional symptoms occur. Pain intensity diminishes and disappears after 15–20 min. Apart from occasional dizziness, no other symptoms occur. The patient has a history of tension-type headache and polycystic ovaries. Blood tests and imaging revealed no abnormalities. Here, we present the first case in Greece. We review the current literature on this rare syndrome and discuss on possible pathophysiology and the investigation of possible co-factors such as anxiety and depression

High origin of a testicular artery: a case report and review of the literature

<p>Abstract</p> <p>Introduction</p> <p>Although variations in the origin of the testicular artery are not uncommon, few reports about a high origin from the abdominal aorta exist in the literature. We discuss the case of a high origin of the testicular artery, its embryology, classification systems, and its clinical significance.</p> <p>Case presentation</p> <p>We report a very rare case of high origin of the left testicular artery in a 68-year-old Caucasian male cadaver. The artery originated from the anterolateral aspect of the abdominal aorta, 2 cm cranially to the ipsilateral renal artery. Approximately 1 cm after its origin, it branched off into the inferior suprarenal artery. During its course, the artery crossed anterior to the left renal artery.</p> <p>Conclusions</p> <p>A knowledge of the variant origin of the testicular artery is important during renal and testicular surgery. The origin and course must be carefully identified in order to preserve normal blood circulation and prevent testicular atrophy. A reduction in gonadal blood flow may lead to varicocele under circumstances. A knowledge of this variant anatomy may be of interest to radiologists and helpful in avoiding diagnostic errors.</p

Optimal management of asymptomatic carotid stenosis in 2021: the jury is still out. An International, multispecialty, expert review and position statement

Objectives: The recommendations of international guidelines for the management of asymptomatic carotid stenosis (ACS) often vary considerably and extend from a conservative approach with risk factor modification and best medical treatment (BMT) alone, to a more aggressive approach with a carotid intervention plus BMT. The aim of the current multispecialty position statement is to reconcile the conflicting views on the topic. Materials and methods: A literature review was performed with a focus on data from recent studies. Results: Several clinical and imaging high-risk features have been identified that are associated with an increased long-term ipsilateral ischemic stroke risk in patients with ACS. Such high-risk clinical/imaging features include intraplaque hemorrhage, impaired cerebrovascular reserve, carotid plaque echolucency/ulceration/ neovascularization, a lipid-rich necrotic core, a thin or ruptured fibrous cap, silent brain infarction, a contralateral transient ischemic attack/stroke episode, male patients <75 years and microembolic signals on transcranial Doppler. There is growing evidence that 80-99% ACS indicate a higher stroke risk than 50-79% stenoses. Conclusions: Although aggressive risk factor control and BMT should be implemented in all ACS patients, several high-risk features that may increase the risk of a future cerebrovascular event are now documented. Consequently, some guidelines recommend a prophylactic carotid intervention in high-risk patients to prevent future cerebrovascular events. Until the results of the much-anticipated randomized controlled trials emerge, the jury is still out regarding the optimal management of ACS patients

Optimal Management of Asymptomatic Carotid Stenosis in 2021:The Jury is Still Out. An International, Multispecialty, Expert Review and Position Statement

Objectives: The recommendations of international guidelines for the management of asymptomatic carotid stenosis (ACS) often vary considerably and extend from a conservative approach with risk factor modification and best medical treatment (BMT) alone, to a more aggressive approach with a carotid intervention plus BMT. The aim of the current multispecialty position statement is to reconcile the conflicting views on the topic. Materials and methods: A literature review was performed with a focus on data from recent studies. Results: Several clinical and imaging high-risk features have been identified that are associated with an increased long-term ipsilateral ischemic stroke risk in patients with ACS. Such high-risk clinical/imaging features include intraplaque hemorrhage, impaired cerebrovascular reserve, carotid plaque echolucency/ulceration/ neovascularization, a lipid-rich necrotic core, a thin or ruptured fibrous cap, silent brain infarction, a contralateral transient ischemic attack/stroke episode, male patients < 75 years and microembolic signals on transcranial Doppler. There is growing evidence that 80–99% ACS indicate a higher stroke risk than 50–79% stenoses. Conclusions: Although aggressive risk factor control and BMT should be implemented in all ACS patients, several high-risk features that may increase the risk of a future cerebrovascular event are now documented. Consequently, some guidelines recommend a prophylactic carotid intervention in high-risk patients to prevent future cerebrovascular events. Until the results of the much-anticipated randomized controlled trials emerge, the jury is still out regarding the optimal management of ACS patients

Cardiovascular disease and the role of oral bacteria

In terms of the pathogenesis of cardiovascular disease (CVD) the focus has traditionally been on dyslipidemia. Over the decades our understanding of the pathogenesis of CVD has increased, and infections, including those caused by oral bacteria, are more likely involved in CVD progression than previously thought. While many studies have now shown an association between periodontal disease and CVD, the mechanisms underpinning this relationship remain unclear. This review gives a brief overview of the host-bacterial interactions in periodontal disease and virulence factors of oral bacteria before discussing the proposed mechanisms by which oral bacterial may facilitate the progression of CVD