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The marine intertidal mussel Mytilus californianus aggregates to form beds along the Pacific shores of North America. As a sessile organism it must cope with fluctuations in temperature during aerial exposure during low-tide events, which elevates maintenance costs and negatively affects their overall energy budget. The function of their digestive gland is to release enzymes that break apart ingested polymers for subsequent nutrient absorption. The effects of elevated aerial warming acclimation on the functioning of digestive gland enzymes are not well studied. In this study we asked whether digestive gland carbohydases and proteases could be overstimulated in warm condition to mitigate the costs related to the heat-shock response. We compared mussels acclimated to a + 9 °C heat-shock during daily low-tide aerial exposure to mussels acclimated to isothermal tidal conditions in a simulated intertidal system. The results showed fairly consistent activities of cellulase, trypsin, and amino-peptidase across tidal variation and between thermal treatments; however, amylase activity was lower in warmed versus cool mussels across low and high-tide. We also observed the expression of heat-shock genes in gill tissue during warm tidal conditions, suggestive that moderate temperatures during aerial exposure can induce a stress response.

This study offers timely empirical evidence of the magnitude of the language effect on the performance of different language user groups, namely English as a Foreign Language (EFL), English as a Second Language (ESL), and English as a Native Language (ENL) in an accounting program instructed in English, an area that has been under researched. Informed by Cognitive Load Theory (CLT), this study develops an innovative research methodology (crossover repeated measures design), drawing on a large data analysis (n = 2912) of students' academic results in six accounting specialisation subjects between 2007 and 2014 in an Australian university's undergraduate accounting program. Results show that while all language user groups perform worse in more conceptually (MC) oriented subjects compared to less conceptually (LC) oriented subjects, the relative performance between MC and LC is strongly related to English language user groups. For the first time the magnitude of the impact is derived. The study has implications for the instructional design of accounting programs in English-speaking universities and their offshore programs in non-English speaking countries.

Background The aim of this study was to evaluate the value of T1/T2-weighted imaging (T1/T2WI) registration to reduce the postbiopsy hemorrhage effect for prostate cancer localization on prostate magnetic resonance imaging (MRI). Methods Twenty-one men with pathology-proven prostate cancer who underwent preoperative MRI in a single institution were selected. The zonal anatomy was divided into 16 sections. T2WI, T1/T2-weighted registered imaging (T1/T2RI), T2WI combined with diffusion-weighted imaging (T2WI + DWI), and T1/T2RI combined with DWI (T1/T2RI + DWI) were scored for the likelihood of cancer by two radiology faculty members and two trainees, and were compared with histology results. Areas under the receiver operating characteristics curve (AUCs) were used to assess diagnostic accuracy. Results For the trainees (Reader 3 and Reader 4), the AUC values were significantly higher (P

We propose an automatic nodule registration method between baseline and follow-up chest CT scans. Initial alignment using the center of the lung volume corrects the gross translational mismatch, and rigid registration using coronal and sagittal maximum intensity projection images effectively refines the rigid motion of the lungs. Nodule correspondences are established by finding the most similar region in terms of density as well as the geometrical constraint. The proposed nodule registration method increased the nodule hit rate (the ratio of the number of successfully matched nodules to total nodule number) from 26% to 100%.

Rationale and Objectives To validate the hypothesis that a multisegmented approach during subtraction computed tomography (CT) angiography of the lower extremities can improve bone removal efficiency by suppressing regional motion. Materials and Methods The institutional review board of our hospital approved this retrospective study. One hundred and one consecutive patients that had undergone the lower extremity CT angiography were included in this study. Subtraction CT angiography was performed using two different methods, namely, by single volume subtraction and by multisegmented volume subtraction. Multisegmented volume subtraction was conducted by dividing the whole volume of the CT data into three segments along the z axis of the lower extremities, performing a subtraction process for each segment, and combining segments to form as single subtracted volume. The bone removal efficiencies of the two methods was assessed by analyzing bone subtraction scores on maximum intensity projection (MIP) images for each bone segment in a blinded fashion. In addition, overall MIP image qualities were compared by displaying MIP images produced using the two methods side by side. Differences between bone subtraction scores were tested using Wilcoxon’s signed rank test. Results Multisegmented volume subtraction MIP images demonstrated significantly better bone removal for the following bone segments: pelvis ( P P = .0002), thigh ( P = .0258), knee ( P = .0004), ankle ( P = .0008), metatarsal bone ( P P Conclusion Bone removal performance and overall MIP image quality can be increased by adopting multisegmented volume subtraction during subtraction CT angiography of the lower extremities.

We propose a new curvature-based method for correcting the segmented lung boundary. Our method consists of the following steps. First, the lungs are extracted from chest CT images by the automatic segmentation method. Second, the segmented lung contours are corrected by lung smoothing in each axial slice. Our scan line search provides an efficient contour tracing and curvature calculation. Finally, the smoothed lung contours are corrected by 3D VOI refinement. This increases the smoothness in the z-axis without distortion of the lung boundary. Experimental results show that our method effectively incorporates the pleural nodules and pulmonary vessels into the segmentation results.

We propose a robust 3D rigid registration and masking techniques for getting a clear arterial anatomy and easily detecting cerebral aneurysms, arterial stenosis and other vascular anomalies in brain CT angiography. Our method is composed of the following steps. First, a set of feature points are automatically selected using a 2D edge detection technique within the ring model. Second, a Gaussian-weighted distance map is constructed for leading our similarity measure to robust convergence on the optimal value. Third, the similarity measure between feature points is evaluated repeatedly by weighted cross-correlation. Fourth, bone-vessel masking and subtraction is performed for completely removing bones. Our method has been successfully applied to 10 patients of pre- and post-contrast images of brain CT angiography. Experimental results show that the performance of our method is very promising compared with conventional methods in the aspects of its visual inspection, accuracy and robustness. Our method can be useful for the early diagnosis and treatment planning of cerebrovascular anomalies in CT angiography.

Background The tissue spanning the mitral and aortic valves, the mitral-aortic intervalvular fibrosa (MAIVF), may be the site of pseudoaneurysm formation in the setting of infective endocarditis or congenital heart disease, or after valve surgery. Because of potential complications of MAIVF pseudoaneurysms, patients with such lesions are often referred for surgical repair. Methods We identified 3 individuals with MAIVF pseudoaneurysms who were followed without surgical intervention after diagnosis of the MAIVF pseudoaneurysm. The courses of these patients are presented below. Results The MAIVF pseudoaneurysms were measured to be stable in size over several years among 3 patients. Dimensions were 5.3 × 2.3, 7.6 × 4.9, and 4.8 × 2.5 cm. Surgical repair was considered too high a risk in 2 of the individuals, and the third individual refused a third surgical intervention. Of the 3 patients, 2 remain asymptomatic. The third patient was 87 years old when her MAIVF pseudoaneurysm was diagnosed, and she died of noncardiac causes at age 92 years. Conclusions Clinical surveillance and serial imaging of MIAVF pseudoaneurysms may be considered an alternative to surgical management in select individuals.