565 research outputs found

    A Score-Based Evaluation Model for Rehabilitation of Existing Pumped Storage Hydropower Plant Construction

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    As the proportion of new and renewable energy increases, power control demands are becoming more frequent due to variability in power generation. As a complementary means against this, the pumped storage hydropower plants (PSHP) are attracting attention as energy storage systems (ESS), but it has high construction costs. Therefore, this study aims to improve the economic feasibility by developing the evaluation model of the existing infrastructure into an upper/lower dam suitable for PSHP. The concept of upper dam capacity is newly defined, and the evaluation index is constructed using normalization. A new evaluation system is presented for five factors: environment, stability, energy, capacity, and economy. Finally, it is tested in the pilot area in Korea. Several candidates, including the PSHP in operation, are found to have been distributed with higher scores. These results will help to satisfy the selection of candidates during the preliminary feasibility study phase, and programming them will enable more accurate and rapid assessment

    The Impact of Overactive Bladder on Health-Related Quality of Life, Sexual Life and Psychological Health in Korea

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    Purpose We aimed to estimate the prevalence of overactive bladder (OAB) in Korea, to assess the variation in prevalence by sex and age, and to measure the impact of OAB on quality of life. Methods A population-based, cross-sectional telephone survey was conducted between April and June 2010 with a questionnaire regarding the prevalence of OAB, demographics, and the impact of OAB on quality of life. A geographically stratified random sample of men and women aged ≥30 years was selected. Results The overall prevalence of OAB was 22.9% (male, 19%; female, 26.8%). Of a total of 458 participants with OAB, 37.6% and 19.9% reported moderate or severe impact on their daily life and sexual life (5.6% and 3.5%, respectively, in participants without OAB). Anxiety and depression were reported by 22.7% and 39.3% of participants with OAB, respectively (9.7% and 22.8%, respectively, in participants without OAB). Only 19.7% of participants with OAB had consulted a doctor for their voiding symptoms, but 50.7% of respondents with OAB were willing to visit a hospital for the management of their OAB symptoms. Conclusions This study confirmed that OAB symptoms are highly prevalent in Korea, and many sufferers appear to have actively sought medical help. OAB has severe effects on daily and sexual life as well as psychological health

    Cost-effectiveness of a medication event monitoring system for tuberculosis management in Morocco

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    BACKGROUND: Digital health technologies have been used to enhance adherence to TB medication, but the cost-effectiveness remains unclear. METHODS: We used the real data from the study conducted from April 2014 to December 2020 in Morocco using a smart pillbox with a web-based medication monitoring system, called Medication Event Monitoring Systems (MEMS). Cost-effectiveness was evaluated using a decision analysis model including Markov model for Multi-drug resistant (MDR) TB from the health system perspective. The primary outcome was the incremental cost-effectiveness ratio (ICER) per disability adjusted life-year (DALY) averted. Two-way sensitive analysis was done for the treatment success rate between MEMS and standard of care. RESULTS: The average total per-patient health system costs for treating a new TB patient under MEMS versus standard of care were 398.70and398.70 and 155.70, respectively. The MEMS strategy would reduce the number of drug-susceptible TB cases by 0.17 and MDR-TB cases by 0.01 per patient over five years. The ICER of MEMS was $434/DALY averted relative to standard of care, and was most susceptible to the TB treatment success rate of both strategies followed by the managing cost of MEMS. CONCLUSION: MEMS is considered cost-effective for managing infectious active TB in Morocco

    A Case of Disseminated Polycystic Dilated Perivascular Spaces Presenting with Dementia and Parkinsonism

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    The perivascular spaces (PVSs) of the brain are lined with pia and contain interstitial fluid. In general, PVSs are small, asymptomatic, and identifiable at all ages. When PVSs are significantly enlarged, they can produce various clinical manifestations such as headache and dizziness. A 67-year-old man was admitted with cognitive impairment and gait disturbance with a 5-month history. Brain MRI showed multiple cystic PVSs in periventricular and subcortical white matter of both hemispheres. Medication with dopaminergic agents produced a moderate clinical improvement, while anticholinesterase was not effective. This case suggests that disseminated polycystic dilated PVSs may present with dementia and Parkinsonism

    Periodic Methylation Patterns in the Background Mucosa of Gastric Cancer

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    Background/Aims Gastrointestinal glandular stem cells renew every 8 years. New stem cells with impeded housekeeping gene methylation have unstable phenotypes and are prone to transform into malignant cells. Age-related changes in methylation in the gastric mucosa were evaluated to define the period of cancer-prone stem cell replacement.Materials and Methods Endoscopic biopsy specimens of normal-appearing gastric mucosa were obtained from 148 Helicobacter pylori-negative controls, 124 H. pylori-positive controls, and 69 gastric cancer patients with closed-type mucosal atrophy. Methylation-variable sites of two stomach-specific genes (TFF2 and TFF3) and four housekeeping genes (CDH1, ARRDC4, MMP2, and CDKN2A) were analyzed using radioisotope-labeled methylation-specific polymerase chain reaction. Age-related methylation was evaluated depending on the gastric mucosal atrophy at 2-year intervals. Results TFF2 methylation peaked periodically at 40 to 41, 48 to 49, 56 to 57, and 64 to 65 years of age in H. pylori-negative controls. Periodic peaks of TFF2 methylation were also found in H. pylori-positive controls. Housekeeping-gene methylation troughed at 48 to 49, 56 to 57, and 68 to 69 years of age in cancer patients. Trough methylation of CDH1 and ARRDC4 was lower in cancer patients than in H. pylori-positive controls. Conclusions Methylation peaks of stomach-specific TFF2 in controls and methylation troughs of housekeeping genes in cancer patients were found every 8 years. Periodic methylation patterns may be used to identify individuals at high risk for gastric cancer

    Early detection of cardiac involvement in Miyoshi myopathy: 2D strain echocardiography and late gadolinium enhancement cardiovascular magnetic resonance

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    <p>Abstract</p> <p>Background</p> <p>Miyoshi myopathy (MM) is an autosomal recessive distal myopathy characterized by early adult onset. Cardiomyopathy is a major clinical manifestation in other muscular dystrophies and an important prognostic factor. Although dysferlin is highly expressed in cardiac muscle, the effect of dysferlin deficiency in cardiac muscle has not been studied. We hypothesized that early myocardial dysfunction could be detected by 2D strain echocardiography and late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR).</p> <p>Method</p> <p>Five consecutive MM patients (3 male) in whom we detected the DYSF gene mutation and age-matched healthy control subjects were included. None of the patients had history of cardiac disease or signs and symptoms of overt heart failure. Patients were studied using 2D strain echocardiography and CMR, with 2D strain being obtained using the Automated Function Imaging technique.</p> <p>Results</p> <p>All patients had preserved left ventricular systolic function. However, segmental Peak Systolic Longitudinal Strain (PSLS) was decreased in 3 patients. Global PSLS was significantly lower in patients with MM than in control subjects (p = 0.005). Basal anterior septum, basal inferior septum, mid anterior, and mid inferior septum PSLS were significantly lower in patients with MM than in control subjects (P < 0.0001, < 0.0001, 0.038 and 0.003, respectively). Four patients showed fibrosis by LGE. The reduced PSLS lesion detected by 2D strain tended to be in the same area as that which showed fibrosis by LGE.</p> <p>Conclusions</p> <p>Patients with MM showed subclinical involvement of the heart. 2D strain and LGE are sensitive methods for detecting myocardial dysfunction prior to the development of cardiovascular symptoms. The prognostic significance of these findings warrants further longitudinal follow-up.</p

    Transparent actuator made with few layer graphene electrode and dielectric elastomer, for variable focus lens

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    A transparent dielectric elastomer actuator driven by few-layer-graphene (FLG) electrode was experimentally investigated. The electrodes were made of graphene, which was dispersed inN-methyl-pyrrolidone. The transparent actuator was fabricated from developed FLG electrodes.The FLG electrode with its sheet resistance of 0.45 kΩ/sq (80 nm thick) was implemented to mask silicone elastomer. The developed FLG-driven actuator exhibited an optical transparency of over 57% at a wavenumber of 600 nm and produced bending displacement performance ranging from 29 to 946 μm as functions of frequency and voltage. The focus variation was clearly demonstrated under actuation to study its application-feasibility in variable focus lens and various opto-electro-mechanical devices

    Determinants of Conductive Hearing Loss in Tympanic Membrane Perforation

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    ObjectivesTympanic membrane perforations are common, but there have been few studies of the factors determining the extent of the resulting conductive hearing loss. The aims of this study were to determine whether the size of tympanic membrane perforation, pneumatization of middle ear & mastoid cavity, and location of perforation were correlated with air-bone gap (ABG) of patients.MethodsForty-two patients who underwent tympanoplasty type I or myringoplasty were included and preoperative audiometry were analyzed. Digital image processing was applied in computed tomography for the estimation of middle ear & mastoid pneumatization volume and tympanic membrane photograph for the evaluation of perforation size and location.ResultsPreoperative mean ABG increased with perforation size (P=0.018), and correlated inversely with the middle ear & mastoid volume (P=0.005). However, perforations in anterior versus posterior locations showed no significant differences in mean ABG (P=0.924).ConclusionThe degree of conductive hearing loss resulting from a tympanic membrane perforation would be expected with the size of perforation and pneumatization of middle ear and mastoid
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