The Basics of Neuroimaging: Techniques, Basic Anatomy and Pathology

This presentation was part of the PEER Liberia Radiology Lecture Series. The presentation provides an overview of neuroimaging techniques including x-rays, computerised tomography, magnetic imaging, angiography, and pathology

Lynch Law in the Land of Lincoln: African American Intellectuals and Early Twentieth Century Race Riots

Abstract: In the early twentieth century, more and more African Americans began to leave the American South in search of better jobs and more equal treatment in the North. These black migrants found a less rigid racial hierarchy and employment in industrial and domestic settings. However, racism in the North was alive and well. As African American communities began to exert their economic and political power, they were often targeted by white mobs who would rampage through black neighborhoods, killing and burning as they went. In response to race riots in Springfield (1908), East St. Louis (1917), and Chicago (1919), black intellectuals would form large, national organizations with the intention of stopping further acts of violence. This era of civil rights was dominated by large intellectual personalities who brought a top-down approach to uplift. Embodied most clearly in W.E.B. Du Bois, groups such as the National Association for the Advancement of Colored People and the National Urban League sought to cultivate a black middle-class to represent the race as a whole positively. While these groups faced criticism from more extreme thinkers to their political right and left, they ultimately distinguished themselves as the dominant voices in civil rights during the time. Unfortunately, the creation of a black middle-class did very little to stem the tide of racial violence or uplift African Americans as a whole. This paper examines the intellectual origins of prominent civil rights leaders and organizations, their programs for racial uplift, and how they ultimately succeeded or failed to bring about positive change

IMECE2005-81656 ASSESSING HYPERCUBE SAMPLING TECHNIQUES FOR RISK ASSESSMENT

ABSTRACT Two variations of hypercube sampling techniques are introduced and computationally tested using benchmark problems. The methods are variations of the Latin hypercube sampling (LHS) and incremental-fractional LHS scheme. Both can be described as stratified sampling with one sample per strata. Because they ensure uniform marginals, they are observed to have computational advantages for linear problems where weighted response statistics are sought. Advantages are less pronounced for non-linear responses and sorted statistics, which is often the case for risk analysis. The complementary cumulative distribution is identified as being helpful in assessing a methods performance. Both methods are applied to an application problem having multiple responses of interest and 48 uncertain inputs. The hypercube methods are noted to produce estimates of the mean with orders-of-magnitude lower variance than that of simple random sampling

Clinical outcomes of a balloon-expandable stent for symptomatic obstructions of the subclavian or innominate arteries

Background: Upper-extremity peripheral arterial disease (PAD) may present with a broad spectrum of signs and symptoms. If an endovascular treatment is planned, percutaneous angioplasty and stent placement may lead to a better patency compared to percutaneous angioplasty alone. We assessed the characteristics and clinical course of patients with upper-extremity PAD who received angioplasty and a balloon-expandable stent. Patients and methods: We analyzed data from consecutive patients treated with angioplasty and placement of a balloon-expandable BeSmooth Peripheral Stent System$^{®}$ (Bentley, Germany) at the Angiology Department (University Hospital Zurich) between 2018 and 2022. The primary outcome was re-intervention at the target lesion within 6 months from index angioplasty and during available follow-up. The study was approved by the local ethical commission. Results: A total of 27 patients were treated. The median age was 70 (Q1-Q3: 60-74) years and 59% were men. The subclavian artery (74%) represented the most frequently treated target lesion, followed by the innominate artery (26%). The mean improvement in blood pressure in the treated arm was 21 (95%CI 7 to 35) mmHg at 24 hours and 29 (95%CI 15 to 43) mmHg at 6 months. At 6 months, 2 (8%) patients required a target lesion re-intervention. During the remaining follow-up period up to 24 months, one of these two patients required additional intervention and a total of 3 (11%) patients died due to sepsis, cancer, and unknown causes, respectively. Conclusions: Percutaneous catheter-based treatment with a balloon-expandable stent for symptomatic upper extremity PAD appeared to be effective and safe

Clinical outcomes of ultrasound-assisted coagulation monitoring-adjusted catheter-directed thrombolysis for acute pulmonary embolism

BACKGROUND Ultrasound-assisted catheter-directed thrombolysis (USAT) may reverse right ventricular dysfunction due to acute pulmonary embolism (PE) with a favorable safety profile. METHODS We studied intermediate-high- and high-risk acute PE patients who underwent USAT at the University Hospital Zurich, 2018-2022. The USAT regimen included alteplase 10 mg per catheter over 15 h, therapeutic-dosed heparin, and dosage adaptations based on routinely monitored coagulation parameters, notably anti-factor Xa activity and fibrinogen. We focused on the mean pulmonary arterial pressure (mPAP) and the National Early Warning Score (NEWS) before and after USAT, and reported the incidence of hemodynamic decompensation, PE recurrence, major bleeding, and death over 30 days. RESULTS We included 161 patients: 96 (59.6 %) were men and the mean age was 67.8 (SD 14.6) years. Mean PAP decreased from a mean of 35.6 (SD 9.8) to 25.6 (SD 8.2) mmHg, whereas the NEWS decreased from a median of 5 (Q1-Q3 4-6) to 3 (Q1-Q3 2-4) points. No cases of hemodynamic decompensation occurred. One (0.6 %) patient had an episode of recurrent PE. Two (1.2 %) major bleeding events occurred, including one (0.6 %) intracranial, fatal hemorrhage in a patient with high-risk PE, severe heparin overdosing, and a recent head trauma (with negative CT scan of the brain performed at baseline). No other deaths occurred. CONCLUSIONS USAT resulted in a rapid improvement of hemodynamic parameters among patients with intermediate-high risk acute PE and selected ones with high-risk acute PE, without any recorded deaths related to PE itself. A strategy including USAT, therapeutic-dosed heparin, and routinely monitored coagulation parameters may partly explain the overall very low rate of major bleeding

Medical revalidation as professional regulatory reform: challenging the power of enforceable trust in the United Kingdom

For more than two decades, international healthcare crises and ensuing political debates have led to increasing professional governance and regulatory policy reform. Governance and policy reforms, commonly representing a shift from embodied trust in professionals to state enforceable trust, have challenged professional power and self-regulatory privileges. However, controversy remains as to whether such policies do actually shift the balance of power and what the resulting effects of policy introduction would be. This paper explores the roll-out and operationalisation of revalidation as medical regulatory reform within a United Kingdom National Health Service hospital from 2012-2013, and its impact upon professional power. Revalidation policy was subject to the existing governance and management structures of the organisation, resulting in the formal policy process being shaped at the local level. This paper explores how the disorganised nature of the organisation hindered rather than facilitated robust processes of professional governance and regulation, fostering formalistic rather than genuine professional engagement with the policy process. Formalistic engagement seemingly assisted the medical profession in retaining self-regulatory privileges whilst maintaining professional power over the policy process. The paper concludes by challenging the concept of state enforceable trust and the theorisation that professional groups are effectively regulated and controlled by means of national and organisational objectives, such as revalidation

The application of electronic techniques to high energy particle detection

The technical implications are discussed, of the physical principles behind ISIS, a large volume nuclear particle detector. The particular solution adopted in ISIS is described, for the accurate acquisition of data at high rates and under poor signal-to-noise conditions. A computer program has been written to simulate the processing of signals and noise within ISIS. To check the validity of the simulation, its predictions have been compared with the results of experiments using prototype equipment. With the aid of the simulation, the performance of ISIS has been investigated as regards the spatial resolution and the particle-identification capability of the device. An optimum design for the whole ISIS device has been attained, as a compromise between this performance and tolerable systematic effects. In addition, it has been shown that, around the operating point, there is an adequate window within which satisfactory performance is maintained.</p