Epidemiological and Genetic Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from the Ear Discharge of Outpatients with Chronic Otitis Media

The origin of methicillin-resistant Staphylococcus aureus (MRSA) strains from otolaryngology outpatients has not been evaluated yet in Korea. We analyzed epidemiologic and genetic characteristics of MRSA isolates from the ear discharge of 64 outpatients with chronic otitis media in a Korean University Hospital during 2004. MRSA strains were grouped as either from the initial visit (n=33) or the follow-up visit (n=31) based on the timing of isolation. Healthcare-associated risk factors were frequently present among patients of the initial visit group, especially prior visit to primary clinic (79%) and antibiotic use (73%). SCCmec typing and multilocus sequence typing results showed that two genotypes, ST5-MRSA-II and ST239-MRSA-III, were prevalent in both the initial visit (73% vs. 24%) and the follow-up visit (55% vs. 42%). Pulsed-field gel electrophoresis identified eight types, including two major types shared by both groups. We conclude that majority of MRSA strains from ear discharge of chronic otitis media belonged to nosocomial clones that might be circulating in the community. This is the first report of the genetic analysis of MRSA strains from otolaryngology practices in Korea

The role of PET/CT in detection of gastric cancer recurrence

<p>Abstract</p> <p>Background</p> <p>In the course of surveillance of gastric cancer recurrence after curative resection, contrast CT scan is used in general. However, new findings from CT scan are not always confirmatory for the recurrence. In this case, we usually use short-term follow up strategy or therapeutic intervention with clinical decision. Recently, the use of fusion Positron Emission Tomography/Computed Tomography (PET/CT) is increasing. The purpose of this study is to evaluate the efficacy and usefulness of PET/CT for detecting recurrence of gastric cancer after curative resection.</p> <p>Methods</p> <p>Fifty two patients who received curative resection of gastric cancer and had undergone PET/CT and contrast CT for surveillance of recurrence until Dec 2006 in Seoul National University Hospital were analyzed retrospectively. Recurrence of gastric cancer was validated by histologic confirmation (n = 17) or serial contrast CT follow up with at least 5 month interval (n = 35). McNemar's test and Fisher's exact test were used to evaluate sensitivity and specificity of PET/CT and contrast CT.</p> <p>Results</p> <p>Of 52 patients, 38 patients were confirmed as recurrence. The sensitivity was 68.4% (26/38) for PET/CT and 89.4% (34/38) for contrast CT (p = 0.057). The specificity was 71.4% (10/14) and 64.2% (9/14), respectively (p = 1.0). In terms of the recurred sites, the sensitivity and specificity of PET/CT were similar to those of contrast CT in all sites except peritoneum. Contrast CT was more sensitive than PET/CT (p = 0.039) for detecting peritoneal seeding. Additional PET/CT on contrast CT showed no further increase of positive predictive value regardless of sites. Among 13 patients whose image findings between two methods were discordant and tissue confirmation was difficult, the treatment decision was made in 7 patients based on PET/CT, showing the final diagnostic accuracy of 42.8% (3/7).</p> <p>Conclusion</p> <p>PET/CT was as sensitive and specific as contrast CT in detection of recurred gastric cancer except peritoneal seeding. However, additional PET/CT on contrast CT did not increase diagnostic accuracy in detection of recurred gastric cancer. Further studies are warranted to validate the role of PET/CT in detection of gastric cancer recurrence.</p

Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació

Modeling consolidation of wax deposition for progressive cavity pump using computational fluid dynamics

This study aims to investigate wax deposition in progressive cavity pumps (PCP), which are widely used in the oil industry. Wax buildup on the walls during extraction can significantly impact the efficiency of the pump, with its thickness being determined by both oil properties and PCP operating conditions. Using computational fluid dynamics (CFD), a detailed analysis of the effect of different specifications, such as rod diameter, rotation speed, inlet velocity, dynamic viscosity, and rod height on wax deposition is conducted. The study also considers the impact of rotational momentum on swirl flow and includes a large-scale simulation of 3,000 cases across a wide range of conditions. Shear rate, a crucial parameter in determining wax thickness, is analyzed and modeled through regression using deep neural networks. This regression model can be used to predict wax thickness based on factors such as inlet velocities, rod diameters, viscosities, and rotation speeds. The results of these large-scale simulations and the proposed regression model will aid in understanding the relationship between operating conditions and oil properties in the context of PCP systems

대뇌반구간 기능해리 현상에 관한 연구

To demonstrate the effect of interhemispheric diaschisis in acute unilateral cerebral infarction, the changes of regional cerebral blood flow (rCBF) following experimental occlusion of one middle cerebral artery(MCA) for up to 16 hours were investigated in an unanesthetized cat model using the technique of transorbital snare ligature implanted in the intact cranium. rCBF of both MCA territories and both marginal zones were measured simultaneously by the hydrogen clearance technique. 25 cats were divided into 2 groups according to the size of infarct; Group A, infarct larger than 10% of ipsilateral coronal sectional surface of hemisphere and Group B, smaller than 10%. DUring the initial stage of ischemia, significant decrease in rCBF of the contralateral hemisphere was observed in both groups, however, in Group A, rCBF gradually increased toward preocclusion level. In Group B, rCBF decreased further and remained low till the 16th hour after occlusion. These results suggested that mild ischemic Group B would take advantage of interhemispheric diaschisis during the late phase of infarct development as well as the substantial collateral flow from the surrounding anterior and posterior cerebral artery territories

Spatial Confinement of the Optical Sensitizer to Realize a Thin Film Organic Photodetector with High Detectivity and Thermal Stability

A thin film planar heterojunction organic photodetector (PHJ-OPD) is demonstrated. Different from a conventional sensitizer-doped photodetector, the limited spatial distribution of sensitizer in a PHJ-OPD enables significantly reduced thickness of the active layer without allowing the formation of unnecessary trap sites and electron percolation pathways. As a result, peak external quantum efficiency (EQE) of 120 700% and detectivity over 1013 Jones are demonstrated with thin active layer thickness of 150 nm, which can be a significant benefit for high-resolution image sensor application. Furthermore, the operating voltage can be decreased to -5 V while maintaining high detectivity over 1012 Jones. Remarkable thermal stability is also observed with minor change in detectivity for 2 h of continuous operation at 60 °C due to morphological robustness of PHJ. This work opens up a possibility of using a thin film PHJ-OPD as a key unit of high-resolution image sensor. © 2017 American Chemical Society.1