Speeded detection of vowels and steady-state consonants

We report two experiments in which vowels and steady-state consonants served as targets in a speeded detection task. In the first experiment, two vowels were compared with one voiced and once unvoiced fricative. Response times (RTs) to the vowels were longer than to the fricatives. The error rate was higher for the consonants. Consonants in word-final position produced the shortest RTs, For the vowels, RT correlated negatively with target duration. In the second experiment, the same two vowel targets were compared with two nasals. This time there was no significant difference in RTs, but the error rate was still significantly higher for the consonants. Error rate and length correlated negatively for the vowels only. We conclude that RT differences between phonemes are independent of vocalic or consonantal status. Instead, we argue that the process of phoneme detection reflects more finely grained differences in acoustic/articulatory structure within the phonemic repertoire

Significance of thromboxane A2 and prostaglandin I2 in acute necrotizing pancreatitis in rats

Plasma thromboxane concentrations were found to be significantly elevated in acute necrotizing pancreatitis in rats, whereas prostaglandin I2 levels were not. The significance of these alterations was investigated. Pancreatitis was induced by injecting 5% sodium taurocholate into the pancreatic duct. Iloprost (ZK 36374, a stable analog of prostaglandin I2, 25 ng/kg body weight) decreased the mortality rate from 100% to 50%. When treatment with iloprost was combined with simultaneous administration of either Sibelium (flunarizine R 14 950, 0.2 mg/kg body weight) or dazmegrel (UK 38 485, 50 mg/kg body weight) an additional decrease in the mortality rate was recorded. Dazmegrel is a selective thromboxane A2 synthetase inhibitor and flunarizine (a calcium entry blocker) also inhibits the effects of elevated thromboxane A2 levels. With flunarizine and iloprost the mortality rate was 40% (P<0.05); with dazmegrel and iloprost it was 10% (P<0.01). The results of the present study suggest that thromboxane A2 and prostaglandin I2 play a role in the course of acute necrotizing pancreatitis

Detection of liver metastases from colorectal carcinoma: Is there a place for routine computed tomography arteriography?

Background. A prospective evaluation of the liver by preoperative ultrasonography, conventional computed tomography (CT), and continuous CT angiography (CCTA) was performed in 60 patients with primary or secondary colorectal carcinoma. Methods. The standards of reference were palpation of the liver and intraoperative ultrasonography. The imaging techniques were assessed independently of each other. Results. In 37 patients 105 liver metastases were identified; 23 patients had no metastases. CCTA had a high sensitivity of 94% (99 lesions identified) in contrast to ultrasonography (48%) and conventional CT (52%). The superiority of CCTA was also manifest in lesions less than 1 cm in diameter. However, the high sensitivity was accompanied by a high false-positive rate, particularly because of variations in the perfusion of normal liver parenchyma. Overall, CCTA had the highest accuracy (74%) compared with ultrasonography and CT (both 57%). The data indicate that preoperative ultrasonography and conventional CT have low sensitivity in the detection of liver metastases. Conclusions. Although CCTA seems to be superior to other preoperative imaging techniques, the too low specificity will hamper its routine application in patients with hepatic metastases from colorectal carcinoma

Comparison of analog and digital preoperative planning in total hip and knee arthroplasties - A prospective study of 173 hips and 65 total knees

Introduction Digital correction of the magnification factor is expected to yield more accurate and reliable preoperative plans. We hypothesized that digital templating would be more accurate than manual templating for total hip and knee arthroplasties. Patients and methods Firstly, we established the interobserver and intraobserver reliability of the templating procedure. The accuracy and reliability of digital and analog plans were measured in a series of 238 interventions, which were all planned using both techniques. Results Interobserver reliability was good for the planning of knee arthroplasties (kappa-values 0.63-0.75), but not more than moderate for the planning of hip arthroplasties (kappa-values 0.22-0.54). Analog plans of knee arthroplasties systematically underestimated the component sizes (1.1 size on average), while the digital procedure proved to be accurate (0.1-0.4 size too small on average). The following figures show percentage of cases receiving a correct implant, allowing an error of one size. Digital templating of the hip arthroplasty was less frequently correct (cemented cup and stem: 72% and 79%; uncemented cup and stem: 52% and 66%) than analog planning (cemented cup and stem: 73% and 89%; uncemented cup and stem: 64% and 52%). Interpretation Planning of component sizes for total knee arthroplasties is an accurate procedure when performed digitally. Our digital preoperative plans which were performed by someone other than the surgeon were less accurate than the analog plans prepared by the surgeon

Acute necrotizing pancreatitis in rats

The specific aim of the present study was to investigate whether eicosanoids play a role in acute necrotizing pancreatitis. Because of the limited number of patients with acute pancreatitis admitted to the hospital each year, as well as the practical difficulties encountered in studying these patients, we had to turn to an experimental model of acute necrotizing pancreatitis. Experimental pancreatitis has been known since 1856 (9) when Claude Bernard injected a mixture of bile and oliYe oil into the pancreatic duct of a dog. We used a model based on the introduction of a bile salt into the pancreatic ducts of rats

Observation of shock waves in a large Bose-Einstein condensate

We observe the formation of shock waves in a Bose-Einstein condensate containing a large number of sodium atoms. The shock wave is initiated with a repulsive, blue-detuned light barrier, intersecting the BEC, after which two shock fronts appear. We observe breaking of these waves when the size of these waves approaches the healing length of the condensate. At this time, the wave front splits into two parts and clear fringes appear. The experiment is modeled using an effective 1D Gross-Pitaevskii-like equation and gives excellent quantitative agreement with the experiment, even though matter waves with wavelengths two orders of magnitude smaller than the healing length are present. In these experiments, no significant heating or particle loss is observed.Comment: 7 pages, 7 figure

Sydney Conservatorium of Music Postgraduate Handbook 2009

In stage III breast carcinoma, metastasized disease needs to be determined. In the past, conventional imaging by liver ultrasound, chest X-ray and bone scintigraphy was the work-up of choice. Recently, FDG-PET/CT was found to have additional value, but clinicians are hesitant to introduce this technique. We present three patients in whom FDG-PET/CT was applied. A 61-year-old woman with stage III breast carcinoma after conventional work-up was upstaged to stage IV breast carcinoma by FDG-PET/CT, upon which her treatment was changed. A 55-year-old woman suspected of stage IV breast carcinoma after conventional imaging was downstaged to stage III after FDG-PET/CT. Her treatment was changed as well. In a 78-year-old woman with recurrent breast carcinoma, the diagnostic certainty of stage III breast carcinoma was increased by FDG-PET/CT. We conclude that FDG-PET/CT is valuable for adequately diagnosing metastases in patients with stage III breast carcinoma and can replace conventional imaging

Effects of control temperature, ablation time, and background tissue in radiofrequency ablation of osteoid osteoma:A computer modeling study

To study the effects of the control temperature, ablation time, and the background tissue surrounding the tumor on the size of the ablation zone on radiofrequency ablation (RFA) of osteoid osteoma (OO). Finite element models of non‐cooled temperature‐controlled RFA of typical OOs were developed to determine the resulting ablation radius at control temperatures of 70, 80, and 90°C. Three different geometries were used, mimicking common cases of OO. The ablation radius was obtained by using the Arrhenius equation to determine cell viability. Ablation radii were larger for higher temperatures and also increased with time. All geometries and control temperatures tested had ablation radii larger than the tumor. The ablation radius developed rapidly in the first few minutes for all geometries and control temperatures tested, developing slowly towards the end of the ablation. Resistive heating and the temperature distribution showed differences depending on background tissue properties, resulting in differences in the ablation radius on each geometry. The ablation radius has a clear dependency not only on the properties of the tumor but also on the background tissue. Lower background tissue's electrical conductivity and blood perfusion rates seem to result in larger ablation zones. The differences observed between the different geometries suggest the need for patient‐specific planning, as the anatomical variations could cause significantly different outcomes where models like the one here presented could help to guarantee safe and successful tumor ablations

Improving Provenance Data Interaction for Visual Storytelling in Medical Imaging Data Exploration

Effective collaborative work in diagnostic medical imaging is not trivial due to the large amounts of complex data involved,a (non-linear) workflow involving experts in different domains, and a lack of versatility in the current tools employed inhealthcare. In this paper, we aim to introduce how the integration of visual storytelling techniques together with provenancedata in the analytic systems used in medicine can compensate for these issues, by enhancing communication of results andreproducibility of findings through diagnostic provenance data. To this end, we illustrate how we can improve the interactionwith provenance data displayed in a graph in order to facilitate authoring and the creation process of visual data storie