271 research outputs found

    Electrical Investigation of the Oblique Hanle Effect in Ferromagnet/Oxide/Semiconductor Contacts

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    We have investigated the electrical Hanle effect with magnetic fields applied at an oblique angle ({\theta}) to the spin direction (the oblique Hanle effect, OHE) in CoFe/MgO/semiconductor (SC) contacts by employing a three-terminal measurement scheme. The electrical oblique Hanle signals obtained in CoFe/MgO/Si and CoFe/MgO/Ge contacts show clearly different line shapes depending on the spin lifetime of the host SC. Notably, at moderate magnetic fields, the asymptotic values of the oblique Hanle signals (in both contacts) are consistently reduced by a factor of cos^2({\theta}) irrespective of the bias current and temperature. These results are in good agreement with predictions of the spin precession and relaxation model for the electrical oblique Hanle effect. At high magnetic fields where the magnetization of CoFe is significantly tilted from the film plane to the magnetic field direction, we find that the observed angular dependence of voltage signals in the CoFe/MgO/Si and CoFe/MgO/Ge contacts are well explained by the OHE, considering the misalignment angle between the external magnetic field and the magnetization of CoFe.Comment: 19 pages, 8 figure

    Valve Location Method for Evaluating Drain Efficiency in Water Transmission Pipelines

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    Water transmission pipelines, which transport bulk water into storage facilities, usually have a tree-type configuration with large dimensions; thus, the breakage of a pipeline may cause a catastrophic service interruption to customers. Although drain efficiency is closely related to the number of washout and control valves and their locations, there is no useful guideline. This paper proposes a valve locating method by introducing numerical analyses to enumerate drainage time and zone. A time integration method, combined with the Newton–Raphson algorithm, is suggested to resolve drainage time, while considering the friction loss in gravitational flow. A drain direction matrix, which shows drain direction and coverage, is derived using a network searching algorithm. Furthermore, a feasible practical approach is presented by introducing a critical horizontal slope, a major washout valve, drainage indices, and control valve embedment. The developed method is first applied to simple pipes to validate the drainage time module. Subsequently, the model is expanded to the CY transmission line, which is one of the BR water supply systems in South Korea currently in operation. The results reveal that three drain valve locations have been neglected, and the addition of control valves guarantees consistent drain time below the operational criteria. Document type: Articl

    Cases of ethical violation in research publications: through editorial decision making process

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    Purpose – To improve and strengthen existing publication and research ethics, KODISA has identified and presented various cases which have violated publication and research ethics and principles in recent years. The editorial office of KODISA has been providing and continues to provide advice and feedback on publication ethics to researchers during peer review and editorial decision making process. Providing advice and feedback on publication ethics will ensure researchers to have an opportunity to correct their mistakes or make appropriate decisions and avoid any violations in research ethics. The purpose of this paper is to identify different cases of ethical violation in research and inform and educate researchers to avoid any violations in publication and research ethics. Furthermore, this article will demonstrate how KODISA journals identify and penalize ethical violations and strengthens its publication ethics and practices. Research design, data and methodology – This paper examines different types of ethical violation in publication and research ethics. The paper identifies and analyzes all ethical violations in research and combines them into five general categories. Those five general types of ethical violations are thoroughly examined and discussed. Results – Ethical violations of research occur in various forms at regular intervals; in other words, unethical researchers tend to commit different types of ethical violations repeatedly at same time. The five categories of ethical violation in research are as follows: (1) Arbitrary changes or additions in author(s) happen frequently in thesis/dissertation related publications. (2) Self plagiarism, submitting same work or mixture of previous works with or without using proper citations, also occurs frequently, but the most common type of plagiarism is changing the statistical results and using them to present as the results of the empirical analysis; (3) Translation plagiarism, another ethical violation in publication, is difficult to detect but occurs frequently; (4) Fabrication of data or statistical analysis also occurs frequently. KODISA requires authors to submit the results of the empirical analysis of the paper (the output of the statistical program) to prevent this type of ethical violation; (5) Mashup or aggregator plagiarism, submitting a mix of several different works with or without proper citations without alterations, is very difficult to detect, and KODISA journals consider this type of plagiarism as the worst ethical violation. Conclusions – There are some individual cases of ethical violation in research and publication that could not be included in the five categories presented throughout the paper. KODISA and its editorial office should continue to develop, revise, and strengthen their publication ethics, to learn and share different ways to detect any ethical violations in research and publication, to train and educate its editorial members and researchers, and to analyze and share different cases of ethical violations with the scholarly community

    The Relationship between the Progression of Kyphosis in Stable Thoracolumbar Fractures and Magnetic Resonance Imaging Findings

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    Study DesignRetrospective study.PurposeTo investigate the relation between the progression of kyphotic deformity and magnetic resonance imaging (MRI) findings in conservatively treated stable thoracolumbar fractures.Overview of LiteratureWhen treated conservatively, excessive progression of kyphotic deformity and vertebral compression can emerge during follow-up. We sought to identify predictors of vertebral body deformation using MR images.MethodsThe presence in MR images of anterior longitudinal ligament (AL) or posterior longitudinal ligament (PL) injury, superior or inferior endplate disruption, superior or inferior disc injury in fractured vertebral bodies, the existence of low signal intensity on T2 weighted images, and bone edema of intravertebral bodies were assessed.ResultsThe presence of superior endplate disruption and a higher level of bone edema were found to cause the progressions of kyphotic angle (KA), wedge angle (WA), and anterior vertebral compression (AVC) rate. When AL or superior disc injury was observed, only KA increased meaningfully. When low signal intensity was present on T2 weighted images WA and AVC increased significantly, but PL injury, inferior endplate disruption, and inferior disc injury showed no notable correlation with kyphotic deformity progression. The risk factors found to be associated with an increase of KA to >5° were AL injury, superior endplate disruption, superior disc injury, and a bone edema level of over 1/3, and their associated risks versus no injury cases were 14.1, 3.7, 6.8, and 10.4-fold, respectively.ConclusionsAL injury, superior endplate and disc injury, or a high level of bone edema, were critical factors that determine kyphotic deformity progression

    Elucidation of Akkermansia muciniphila Probiotic Traits Driven by Mucin Depletion

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    Akkermansia muciniphila is widely considered a next-generation beneficial microbe. This bacterium resides in the mucus layer of its host and regulates intestinal homeostasis and intestinal barrier integrity by affecting host signaling pathways. However, it remains unknown how the expression of genes encoding extracellular proteins is regulated in response to dynamic mucosal environments. In this study, we elucidated the effect of mucin on the gene expression and probiotic traits of A. muciniphila. Transcriptome analysis showed that the genes encoding most mucin-degrading enzymes were significantly upregulated in the presence of mucin. By contrast, most genes involved in glycolysis and energy metabolic pathways were upregulated under mucin-depleted conditions. Interestingly, the absence of mucin resulted in the upregulation of 79 genes encoding secreted protein candidates, including Amuc-1100 as well as members of major protein secretion systems. These transcript level changes were consistent with the fact that administration of A. muciniphila grown under mucin-depleted conditions to high-fat diet-induced diabetic mice reduced obesity and improved intestinal barrier integrity more efficiently than administration of A. muciniphila grown under mucin-containing conditions. In conclusion, mucin content in the growth medium plays a critical role in the improvement by A. muciniphila of high-fat diet-induced obesity, intestinal inflammation, and compromised intestinal barrier integrity related to a decrease in goblet cell density. Our findings suggest the depletion of animal-derived mucin in growth medium as a novel principle for the development of A. muciniphila for human therapeutics

    Tunable Polarization-Dependent Loss Element Based on Acoustooptic Mode Coupling in a Polarization-Maintaining Fiber

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    Abstract-We demonstrate a tunable polarization-dependent loss (PDL) element based on the polarization-dependent coupling of the fundamental core mode to the cladding mode by the flexural acoustic wave in a polarization-maintaining fiber with an elliptical stress member. The resonant wavelength of PDL is tunable by adjusting the frequency of radio-frequency (RF) signal applied to the acoustic transducer, while the magnitude of PDL is variable by the voltage of the same RF signal. Over the wavelength from 1530 to 1570 nm, the variable ranges of PDL for two linear orthogonal polarizations are 16 and 17 dB, respectively

    The origin of proinflammatory cytokines in patients with idiopathic dilated cardiomyopathy.

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    Proinflammatory cytokines and their receptors are increased in the peripheral blood of patients with heart failure. We measured cytokines and their receptors in systemic artery (SA), coronary sinus (CS) and infra-renal inferior vena cava (IVC), in order to investigate their origin and influential factors. Thirty patients with idiopathic dilated cardiomyopathy were performed echocardiography at admission, and right heart catheterization after stabilization. Blood was drawn from 3 sites for measurement of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and soluble tumor necrosis factor-alpha receptor (sTNFR) I, II. TNF-alpha at CS (3.25 +/- 0.34 pg/mL) was higher than those of SA (1.81 +/- 0.39 pg/mL) and IVC (1.88 +/- 0.38 pg/mL, p<0.05). IL-6 at CS (18.3 +/- 3.8 pg/mL) was higher than that of SA (5.8 +/- 1.2 pg/mL, p<0.01). The levels of sTNFR I, II showed increasing tendency in sequence of SA, IVC and CS. TNF-alpha and sTNFR I, II from all sites were proportional to worsening of functional classes at admission (p<0.05). E/Ea by Doppler study at admission, which reflects left ventricular end-diastolic pressure (LVEDP) was positively correlated with TNF-alpha from SA (R=0.71, p<0.01), CS (R=0.52, p<0.05) and IVC (R=0.46, p<0.05). Thus, elevated LVEDP during decompensation might cause cytokine release from myocardium in patients with idiopathic dilated cardiomyopathy

    Impact of Body Mass Index on the relationship of epicardial adipose tissue to metabolic syndrome and coronary artery disease in an Asian population

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    <p>Abstract</p> <p>Background</p> <p>In a previous study, we demonstrated that the thickness of epicardial adipose tissue (EAT), measured by echocardiography, was increased in patients with metabolic syndrome (MS) and coronary artery disease (CAD). Several studies on obese patients, however, failed to demonstrate any relationship between EAT and CAD. We hypothesized that body mass index (BMI) affected the link between EAT and MS and CAD.</p> <p>Methods</p> <p>We consecutively enrolled 643 patients (302 males, 341 females; 59 ± 11 years), who underwent echocardiography and coronary angiography. The EAT thickness was measured on the free wall of the right ventricle at the end of diastole. All patients were divided into two groups: high BMI group, ≥27 kg/m<sup>2 </sup>(n = 165), and non-high BMI group, < 27 kg/m<sup>2 </sup>(n = 478).</p> <p>Results</p> <p>The median and mean EAT thickness of 643 patients were 3.0 mm and 3.1 ± 2.4 mm, respectively. In the non-high BMI group, the median EAT thickness was significantly increased in patients with MS compared to those without MS (3.5 vs. 1.9 mm, p < 0.001). In the high BMI group, however, there was no significant difference in the median EAT thickness between patients with and without MS (3.0 vs. 2.5 mm, p = 0.813). A receiver operating characteristic (ROC) curve analysis predicting MS revealed that the area under the curve (AUC) of the non-high BMI group was significantly larger than that of the high BMI group (0.659 vs. 0.506, p = 0.007). When compared to patients without CAD, patients with CAD in both the non-high and high BMI groups had a significantly higher median EAT thickness (3.5 vs. 1.5 mm, p < 0.001 and 4.0 vs. 2.5 mm, p = 0.001, respectively). However, an ROC curve analysis predicting CAD revealed that the AUC of the non-high BMI group tended to be larger than that of the high BMI group (0.735 vs. 0.657, p = 0.055).</p> <p>Conclusions</p> <p>While EAT thickness was significantly increased in patients with MS and CAD, the power of EAT thickness to predict MS and CAD was stronger in patients with BMI < 27 kg/m<sup>2</sup>. These findings showed that the measurement of EAT thickness by echocardiography might be especially useful in an Asian population with a non-high BMI, less than 27 kg/m<sup>2</sup>.</p
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