6 research outputs found
Design, development and validation of more realistic models for teaching breast examination
No full textOur objective was to design, develop and validate better clinical breast examination (CBE) models addressing the deficiencies of previous models. Detailed research and amethodological design approach led to the development of a new technique for creating lifelike models for teaching CBE. Six multi-layered breast models representing a range of normal human variation for durity (hardness/softness), nodularity (fibro-glandular tissue) and adiposity (fatty tissue) were developed and validated. Various construction materials, MRI scans, traditional casting and three-dimensional (3D) printing were used to build models with lifelike look and feel (biofidelic). The models realistic in anthropometry (size and shape), feel (durity and nodularity) and appearance (skin feel and colouring) – visual biofidelity enhances perception of feel– incorporate anatomically correct layering of ribs, soft adipose tissue, nodularity and additional signs of breast disease, both benign and pathological.These were validated by four breast surgeons who compared their feel alongside a sample of breast patients (N = 78). Models were rated as ‘undecided’, ‘similar’ or ‘very similar’ to 81% of patients for nodularity and 82% for durity. These are the first models to incorporate normal human variability and be validated with real patients. These novelbiofidelic models provide a standardized way of teaching health professionals normal from abnormal.Applied Ergonomics and Desig
Temporary Vessel Occlusion and Barbiturate Protection in Cerebral Aneurysm Surgery
No full textAbstract
In a review of 147 patients with intracranial aneurysms surgically treated by one surgeon (FAD) between 1980 and 1987, 36 selected patients received intraoperative barbiturate protection with sodium thiopental during temporary arterial occlusion. Thiopental doses of 5 to 15 mg/kg were used. Twenty-nine of 36 (81%) had ruptured aneurysms. Occlusion times ranged from 3 to 93 minutes, with a mean of 16.2 minutes. Seven patients had new neurological deficit in the immediate postoperative period, but in only two did these persist. Twenty-one patients (72%) with subarachnoid hemorrhage and 6 with incidental aneurysms made a good recovery. Of the 9 patients with significant permanent deficit, all but 2 were related to either the severity of the initial hemorrhage or to delayed vasospasm. In only one instance might temporary arterial occlusion have led to permanent neurological sequelae. Temporary arterial occlusion with barbiturate protection is a safe technique. For aneurysms that are more surgically complex, it allows for complete dissection of the aneurysm neck and identification and preservation of the surrounding vascular anatomy, while reducing the risk of intraoperative rupture and postoperative stroke.</jats:p
Spotlight on the Multimedia Signal Processing Technical Committee
No full textInternational audienceThe Multimedia Signal Processing Technical Committee (MMSP-TC) of the IEEE Signal Processing Society (SPS) promotes the advancement of multimedia signal processing technology. The scope of the TC includes joint processing/representation of audiovisual and multimodal information, fusion/fission of sensor information or multimodal data, integration of media, art and multimedia technology, and analysis and feature extraction of multimodal data. Other key areas encompass virtual reality and 3D imaging, multimedia communications and networking, human-machine interface and interaction, visual and auditory quality assessment, multimedia databases and digital libraries. In this context, the TC also serves as an incubator of technologies that lie in the gaps between traditional areas. Each year, the MMSP-TC organizes the IEEE International Workshop on Multimedia Signal Processing (MMSP), which attracts researchers from SPS and related communities that work on multimedia topics. Running as a single-track event, the workshop consists of oral and poster sessions, including special sessions that capture specific research trends. It also includes invited plenary presentations (in 2018, G. Durity from Electronic Arts, J.-N. Hwang from University of Washington, and H. Malvar from Microsoft Research) and panel discussions (in 2017, on deep learning in multimedia signal processing research). The workshop typically receives around 150 paper submissions and has more than 100 attendees from all over the world. The workshop has been effective at building a community around the thematic of multimedia signal processing, and it enjoys a good reputation among researchers/academics. To further strengthen the event, the TC is also considering means to more effectively engage industry and students. Pictures of the 2017 and 2018 events are shown in Figure 1 and Figure 2. Figure 1: MMSP 2017 in London-Luton, UK
Effect of phenoxybenzamine on cerebral blood flow and metabolism in the baboon during hemorrhagic shock.
No full textExperiments were performed on 2 groups of baboons anesthetized with Sernylan. One group served as control and the other was premedicated with 5 mg/kg phenoxybenzamine (PBZ). A 2-step hypovolemic shock model was used followed by retransfusion of the shed blood. Cerebral blood flow was measured by the 133Xe clearance method. Arterial and cerebral venous samples were taken and analyzed for blood gases as well as glucose and lactate content. The cerebral metabolic rates of oxygen, glucose, and lactate were calculated. In addition, the effect of CO2 inhalation was studied before shock was induced. PBZ produced no effect on either CBF or the flow response to CO2 prior to bleeding. PBZ pretreatment prevented the fall in cerebral blood flow and CMRO2 produced by systemic hypotension due to bleeding. Lactic acid showed no evidence of change either in production or uptake by the brain during the experimental procedure. The cerebral metabolic pathway of glucose, however, seemed to be affected by PBZ both before and during shock.</jats:p
Can Long Passwords Be Secure and Usable?
No full textTo encourage strong passwords, system administrators employ password-composition policies, such as a traditional policy requiring that passwords have at least 8 characters from 4 character classes and pass a dictionary check. Recent research has suggested, however, that policies requiring longer passwords with fewer additional requirements can be more usable and in some cases more secure than this traditional policy. To explore long passwords in more detail, we conducted an online experiment with 8,143 participants. Using a cracking algorithm modified for longer passwords, we evaluate eight policies across a variety of metrics for strength and usability. Among the longer policies, we discover new evidence for a security/usability tradeoff, with none being strictly better than another on both dimensions. However, several policies are both more usable and more secure that the traditional policy we tested. Our analyses additionally reveal common patterns and strings found in cracked passwords. We discuss how system administrators can use these results to improve password-composition policies
