Segmented RF shield design to minimize eddy currents for low-field Halbach MRI systems.

MRI systems have a thin conducting layer placed between the gradient and RF coils, this acts as a shield at the RF-frequency, minimizing noise coupled into the experiment, and decreasing the coupling between the RF and gradient coils. Ideally, this layer should be transparent to the gradient fields to reduce eddy currents. In this work the design of such a shield, specifically for low-field point-of-care Halbach based MRI devices, is discussed. A segmented double layer shield is designed and constructed based on eddy current simulations. Subsequently, the performance of the improved shield is compared to a reference shield by measuring the eddy current decay times as well as using noise measurements. A maximum reduction factor of 2.9 in the eddy current decay time is observed. The segmented shield couples in an equivalent amount of noise when compared to the unsegmented reference shield. Turbo spin echo images of a phantom and the brain of a healthy volunteer show improvements in terms of blurring using the segmented shield.

Driver distraction and in-vehicle interventions: A driving simulator study on visual attention and driving performance.

Driving simulator studies are popular means to investigate driving behaviour in a controlled environment and test safety-critical events that would otherwise not be possible in real-world driving conditions. While several factors affect driving performance, driving distraction has been emphasised as a safety-critical issue across the globe. In this context, this study explores the impact of distraction imposed by mobile phone usage, i.e., writing and reading text messages, on driver behaviour. As part of the greater i-DREAMS project, this study uses a car driving simulator experimental design in Germany to investigate driver behaviour under various conditions: (I) monitoring scenario representing normal driving conditions, (II) intervention scenario in which drivers receive fixed timing in-vehicle intervention in case of unsafe driving manoeuvres, and (III) distraction scenario in which drivers receive in-vehicle interventions based on task completion capability, where mobile phone distraction is imposed. Besides, eye-tracking glasses are used to further explore drivers' attention allocation and eye movement behaviour. This research focuses on driver response to risky traffic events (i.e., potential pedestrian collisions, and tailgating) and the impact of distraction on driving performance, by analysing a set of eye movement and driving performance measures of 58 participants. The results reveal a significant change in drivers' gaze patterns during the distraction drives with significantly higher gaze points towards the i-DREAMS intervention display (the utilised advanced driver assistance systems in this study). The overall statistical analysis of driving performance measures suggests nearly similar impacts on driver behaviour during distraction drives; a higher deviation of lateral positioning was noted irrespective of the event risk levels and lower longitudinal acceleration rates were observed for pedestrian collisions and non-critical events during distracted driving.

An integrated target field framework for point-of-care halbach array low-field MRI system design.

OBJECTIVE: Low-cost low-field point-of-care MRI systems are used in many different applications. System design has correspondingly different requirements in terms of imaging field-of-view, spatial resolution and magnetic field strength. In this work an iterative framework has been created to design a cylindrical Halbach-based magnet along with integrated gradient and RF coils that most efficiently fulfil a set of user-specified imaging requirements. METHODS: For efficient integration, target field methods are used for each of the main hardware components. These have not been used previously in magnet design, and a new mathematical model was derived accordingly. These methods result in a framework which can design an entire low-field MRI system within minutes using standard computing hardware. RESULTS: Two distinct point-of-care systems are designed using the described framework, one for neuroimaging and the other for extremity imaging. Input parameters are taken from literature and the resulting systems are discussed in detail. DISCUSSION: The framework allows the designer to optimize the different hardware components with respect to the desired imaging parameters taking into account the interdependencies between these components and thus give insight into the influence of the design choices.

Challenges and opportunities for general practice specific CME in Europe - a narrative review of seven countries.

BACKGROUND: Several changes have led to general practitioners (GPs) working in a more differentiated setting today and being supported by other health professions. As practice changes, primary care specific continuing medical education (CME) may also need to adapt. By comparing different primary care specific CME approaches for GPs across Europe, we aim at identifying challenges and opportunities for future development. METHODS: Narrative review assessing, analysing and comparing CME programs for general practitioners across different north-western European countries (UK, Norway, the Netherlands, Belgium (Flanders), Germany, Switzerland, and France). Templates containing detailed items across seven dimensions of country-specific CME were developed and used. These dimensions are role of primary care within the health system, legal regulations regarding CME, published aims of CME, actual content of CME, operationalisation, funding and sponsorship, and evaluation. RESULTS: General practice specific CME in the countries under consideration are presented and comparatively analysed based on the dimensions defined in advance. This shows that each of the countries examined has different strengths and weaknesses. A clear pioneer cannot be identified. Nevertheless, numerous impulses for optimising future GP training systems can be derived from the examples presented. CONCLUSIONS: Independent of country specific CME programs several fields of potential action were identified: the development of curriculum objectives for GPs, the promotion of innovative teaching and learning formats, the use of synergies in specialist GP training and CME, the creation of accessible yet comprehensive learning platforms, the establishment of clear rules for sponsorship, the development of new financing models, the promotion of fair competition between CME providers, and scientifically based evaluation.

Reducing the negative appendectomy rate with the laparoscopic appendicitis score; a multicenter prospective cohort and validation study.

BACKGROUND: Approximately nine percent of all acute appendectomies are unintentionally performed on a normal appendix. Failure of treatment (negative appendectomy or missed appendicitis) is associated with higher morbidity and mortality when compared to appendectomy for uncomplicated appendicitis. The Laparoscopic APPendicitis (LAPP) score was developed in order to systematically evaluate the appendix for the presence of inflammation. This study aims to determine whether the LAPP score reduces the negative appendectomy rate without missing appendicitis. METHODS: From September 2013 through May 2016, 322 adult patients presenting with a clinical suspicion of acute appendicitis and an indication for diagnostic laparoscopy were included and analyzed in this multicenter prospective validation study. Depending on the LAPP score, the appendix was either removed (n = 300) or left in situ (n = 22). These patients were compared to a historical control group of 584 patients treated at the same hospitals. The appendix was examined by a pathologist and the negative appendectomy rate was calculated. RESULTS: The negative appendectomy rate was significantly lower when the LAPP score was used (4,7% vs. 8,4%; P = 0,034). None of the patients with a negative LAPP score, in which the appendix remained in situ, developed acute appendicitis within three months. There were no significant differences in operation time, complications, or readmissions. Using the LAPP score was associated with significantly higher rates of preoperative radiological imaging (98% vs. 70%; P < 0,001). After adjusting for covariables, including radiological imaging, use of the LAPP score led to fewer treatment failures when compared to not using the LAPP score (OR: 0,48, 95% C.I. 0,251 to 0,914; P = 0,025). CONCLUSION: The LAPP score is a safe and simple tool to reduce the negative appendectomy rate during laparoscopic surgery without missing cases of acute appendicitis.

Malignant mesothelioma in Sub-Saharan Africa: A case report from Lubumbashi, DR Congo.

Although asbestos has been used throughout Africa in the past decades, no reports of asbestos-related malignant mesothelioma are available from sub-Saharan Africa, except from South Africa and Zimbabwe. We present a case of a 39-year-old man who died from a histologically proven malignant mesothelioma of the peritoneum in Lubumbashi, DR Congo. No occupational exposure to asbestos could be found in his history. In view of his young age, we speculated that he had been exposed to asbestos as a child, which was highly plausible because he had grown up in one of the numerous mining estates of the region. The houses of these estates were often built with asbestos-containing materials, notably roofs made of corrugated asbestos-cement. The possibility of past domestic or environmental exposure to asbestos was substantiated by the identification of chrysotile and crocidolite fibres in samples of asbestos-cement collected from the home where the patient had lived as a child. To our knowledge, this is the first report of malignant mesothelioma from a country in the Central African region. We expect that heightened awareness and improved diagnosis will lead to the detection of more asbestos-related diseases in Africa.

The communication of "pure" group-based anger reduces tendencies toward intergroup conflict because it increases out-group empathy.

The communication of group-based anger in intergroup conflict is often associated with destructive conflict behavior. However, we show that communicating group-based anger toward the out-group can evoke empathy and thus reduce intergroup conflict. This is because it stresses the value of maintaining a positive long-term intergroup relationship, thereby increasing understanding for the situation (in contrast to the communication of the closely related emotion of contempt). Three experiments demonstrate that the communication of group-based anger indeed reduces destructive conflict intentions compared with (a) a control condition (Experiments 1-2), (b) the communication of group-based contempt (Experiment 2), and (c) the communication of a combination of group-based anger and contempt (Experiments 2-3). Moreover, results from all three experiments reveal that empathy mediated the positive effect of communicating "pure" group-based anger. We discuss the implications of these findings for the theory and practice of communicating emotions in intergroup conflicts.