Gravitational waves from cosmic bubble collisions

Cosmic bubbles are nucleated through the quantum tunneling process. After nucleation they would expand and undergo collisions with each other. In this paper, we focus in particular on collisions of two equal-sized bubbles and compute gravitational waves emitted from the collisions. First, we study the mechanism of the collisions by means of a real scalar field and its quartic potential. Then, using this model, we compute gravitational waves from the collisions in a straightforward manner. In the quadrupole approximation, time-domain gravitational waveforms are directly obtained by integrating the energy-momentum tensors over the volume of the wave sources, where the energy-momentum tensors are expressed in terms of the scalar field, the local geometry and the potential. We present gravitational waveforms emitted during (i) the initial-to-intermediate stage of strong collisions and (ii) the final stage of weak collisions: the former is obtained numerically, in \textit{full General Relativity} and the latter analytically, in the flat spacetime approximation. We gain qualitative insights into the time-domain gravitational waveforms from bubble collisions: during (i), the waveforms show the non-linearity of the collisions, characterized by a modulating frequency and cusp-like bumps, whereas during (ii), the waveforms exhibit the linearity of the collisions, featured by smooth monochromatic oscillations.Comment: 17 pages, 5 figure

Endoscopic Submucosal Dissection for Colitis-Associated Dysplasia

Dysplasia is a precancerous lesion of colorectal cancer in patients with long-standing inflammatory bowel diseases (IBDs), such as ulcerative colitis and Crohn’s disease. Recent guidelines suggest endoscopic resection as a key modality for the treatment of endoscopically resectable dysplasia in patients with colitis. Endoscopic submucosal dissection (ESD) has been suggested as one of the therapeutic options for dysplasia that is potentially resectable but not suitable for the conventional endoscopic mucosal resection technique. Several recent studies supported the feasibility of ESD for the treatment of colitis-associated dysplasia in terms of the en bloc and complete resection rates and the risk of procedure-related complications. However, these studies were performed exclusively in expert centers. Moreover, the local and metachronous recurrence rates were relatively high, and long-term outcome data are still lacking. Endoscopists should be highly skilled in colorectal ESD and have an intensive understanding of not only the lesions but also the conditions of patients with IBDs. Therefore, the decision to perform ESD for colitis-associated dysplasia should be made scrupulously after careful discussion with patients, in collaboration with a multidisciplinary IBD team including physicians, surgeons, and pathologists specialized in IBDs

Management of complications related to colorectal endoscopic submucosal dissection

Compared to endoscopic mucosal resection (EMR), colonoscopic endoscopic submucosal dissection (C-ESD) has the advantages of higher en bloc resection rates and lower recurrence rates of colorectal neoplasms. Therefore, C-ESD is considered an effective treatment method for laterally spread tumors and early colorectal cancer. However, C-ESD is technically more difficult and requires a longer procedure time than EMR. In addition to therapeutic efficacy and procedural difficulty, safety concerns should always be considered when performing C-ESD in clinical practice. Bleeding and perforation are the main adverse events associated with C-ESD and can occur during C-ESD or after the completion of the procedure. Most bleeding associated with C-ESD can be managed endoscopically, even if it occurs during or after the procedure. More recently, most perforations identified during C-ESD can also be managed endoscopically, unless the mural defect is too large to be sutured with endoscopic devices or the patient is hemodynamically unstable. Delayed perforations are quite rare, but they require surgical treatment more frequently than endoscopically identified intraprocedural perforations or radiologically identified immediate postprocedural perforations. Post-ESD coagulation syndrome is a relatively underestimated adverse event, which can mimic localized peritonitis from perforation. Here, we classify and characterize the complications associated with C-ESD and recommend management options for them

Internet Customer Segmentation Using Web Log Data

The objective of this paper is to analyze web transaction log data that reveal customer behavior in the Internet channel, and to provide a useful online customer segmentation scheme. To achieve this, we analyze the relationship between the behavior of customers for online pet shops and revenue. We use the decision-tree method as a data-mining technique, and clustering analysis to segment customers.  We perform the study in two stages. First, we investigate the web transaction data of both the member customers and nonmember customers of a Korean online pet shop. Second, we narrow down the study focus and analyze only the member customers’ demographic data and their web transaction data. As a result, we obtain several meaningful segments based on customers’ transaction behavior and demographic characteristics. We use web log data to analyze customer transaction behavior and log-in information to analyze customer demographic characteristics. We discuss some strategic implications, for online shopping mall marketing, suggested by the acquired market segments

Prediction of Advanced Fibrosis in Nonalcoholic Fatty Liver Disease: An Enhanced Model of BARD Score.

UNLABELLED: BACKGROUNDAIMS: The BARD score is a model to detect advanced liver fibrosis in nonalcoholic fatty liver disease (NAFLD) patients. The aims of this study were to identify additional factors and then to build an enhanced version of the BARD score. METHODS: One hundred seven patients with biopsy-proven NAFLD were enrolled retrospectively. Logistic regressions were performed to identify independent risk factors for advanced liver fibrosis (stage 3 or 4). An enhanced model of the BARD score (BARDI score) was built and evaluated with a receiver operating characteristic (ROC) curve. RESULTS: In multivariate analysis, age (odds ratio [OR], 0.89; p=0.04), aspartate aminotransferase/alanine aminotransferase ratio (OR, 1.73; p CONCLUSIONS: The BARDI score had an improved PPV over the BARD score and maintained an excellent NPV. Further study is warranted for its external validation and comparison with other models

COMPARISON OF GAIT ANALYSIS BETWEEN ADOLESCENT IDIOPATHIC SCOLIOSIS PATIENTS AND AGE MATCHED CONTROLS

The purpose of this study was to compare kinematic variables and surface EMG values between adolescent idiopathic scoliosis patients and age matched controls during a gait. Six male patients and five male healthy subjects were recruited for this study. Six cameras were used for 3D motion capture and selected joint angles were computed. Eight pairs of surface EMG electrodes were placed on latissimus dorsi, psoas, glutaeus medius, and biceps femoris. Results revealed that the scoliosis patients showed smaller hip joint angles compared to the values of the controls and vice versa for the trunk tilting angle. Small EMG activity of latissimus dorsi also found from the patient group. This meant that the scoliosis clearly influenced to the abnormal posture during a gait. Such results may be helpful to develop rehabilitation exercise or device