173 research outputs found

    Natural durability of some hardwoods imported into korea for deck boards against decay fungi and subterranean termite in accelerated laboratory tests

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    This study evaluated the natural durability of seven imported hardwoods (bangkirai, burckella, ipe, jarrah, kempas, malas, and merbau) used for deck boards against decay fungi (Fomitopsis palustris, Gloeophyllum trabeum, Trametes versicolor, and Irpex lacteus) and the subterranean termite (Reticulitermes speratus kyushuensis) in accelerated laboratory tests. Ipe, jarrah, and merbau were very durable to fungal attack, with performance comparable to ACQ-treated wood. Bangkirai, burckella, kempas, and malas were classified as durable or moderately durable, depending on the fungal species tested. All wood species except for merbau were highly resistant to termite attack. Termite resistance was similar to ACQ-treated wood. Merbau showed somewhat less than all other species but still significant termite resistance. These results indicated that selected naturally durable hardwood species could inhibit fungal and termite attacks as effectively as ACQ treatment. The natural durability of wood species tested in this study is most likely due to the biocidal extractive content of the wood

    Analysis of Online Home Training Users’ Behavioral Intention and Use Behavior Based on the UTAUT Model: Moderating Roles of Risk Perception toward the COVID-19 Infection and Generational Difference

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    PURPOSE This study aimed (1) to analyze the behavioral intention and use behavior among the consumers of online home training contents via YouTube by employing the unified theory of acceptance and use of technology (UTAUT); (2) to test the moderating effects of risk perception toward the coronavirus (COVID-19) infection, and 3) to test differential impacts of generational difference across millennial and baby boom generations. METHODS A total of 400 questionnaires were distributed, and 383 samples were used for the final analysis after excluding 17 incomplete responses. Data were analyzed using the SPSS 25.0 and AMOS 22.0. RESULTS It was found that (1) the performance expectancy, the effort expectancy, and the social influence had positive effects on behavioral intention; (2)the facilitating condition had negative effects on the use behavior; (3) the behavioral intention had positive impact on the use behavior. Moreover, the risk perception toward the COVID-19 infection did not have moderating impacts on the UTAUT model, whereas generational differences did. CONCLUSIONS Our results suggest that the marketing strategy that improves exercise performance, convenience, and social influencing factors may be key to home training customers' behavioral intention and use behavior. Furthermore, home training material makers should recognize that the features and infrastructure required for the two generations are distinct and develop a separate marketing strategy for each

    Evaluation of an immunochromatographic assay for the detection of anti-hepatitis A virus IgM

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    <p>Abstract</p> <p>Background</p> <p>Hepatitis A virus (HAV) is a causative agent of acute hepatitis, which is transmitted by person-to-person contact and via the faecal-oral route. Acute HAV infection is usually confirmed by anti-HAV IgM detection. In order to detect anti-HAV IgM in the serum of patients infected with HAV, we developed a rapid assay based on immunochromatography (ICA) and evaluated the sensitivity of this assay by comparing it with a commercial microparticle enzyme immunoassay (MEIA) that is widely used for serological diagnosis.</p> <p>Results</p> <p>The newly developed ICA showed 100% sensitivity and specificity when used to test 150 anti-HAV IgM-positive sera collected from infected patients and 75 negative sera from healthy subjects. Also, the sensitivity of ICA is about 10 times higher than MEIA used in this study by determining end point to detect independent on infected genotype of HAV. In addition, the ICA was able to detect 1 positive sample from among 50 sera from acute hepatitis patients that had tested negative for anti-HAV IgM using the MEIA.</p> <p>Conclusion</p> <p>Conclusively, ICA for the detection of anti-HAV IgM will be very effective for rapid assay to apply clinical diagnosis and epidemiological investigation on epidemics due to the simplicity, rapidity and specificity.</p

    EFFECTS OF WALKING SPEED AND AGE ON THE DIRECTIONAL STRIDE REGULARJRY AND GAIT VARIABILITY IN TREADMILL WALKING

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    The purpose of this study was to assess the directional stride regularity (SR) and gait variability (GV) of data from shoe-type inertial measurement unit (IMU) sensors during levelled treadmill walking. The DynaStabtm (IMU based gait analysis system) including Smart Balance' (shoe-type data logger) was used to collect normal gait data from forty-four subjects in their 20s (n=20), 40s (n=13), and 60s (n=ll). Four different walking speeds (3, 4, 5, and 6 km/h, respectively) on a treadmill were applied for one-minute of continuous levelled walking. Only lateral kinematics (mediolateral acceleration and yawing and rolling angular velocities) revealed significant interactions from walking speed and age, demonstrating lower stride regularity and higher gait variability than the anteroposterior and vertical kinematics

    The combination effect of sodium butyrate and 5-Aza-2'-deoxycytidine on radiosensitivity in RKO colorectal cancer and MCF-7 breast cancer cell lines

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    <p>Abstract</p> <p>Background</p> <p>The overall level of chromatin compaction is an important mechanism of radiosensitivity, and modification of DNA methylation and histone deacetylation may increase radiosensitivity by altering chromatin compaction. In this study, we investigated the effect of a demethylating agent, a histone deacetylase(HDAC) inhibitor, and the two agents combined on radiosensitivity in human colon and breast cancer cell lines.</p> <p>Methods</p> <p>In this study, we used RKO colorectal cancer cell line and MCF-7 breast cancer cell lines and normal colon cell lines. On each of the cell lines, we used three different agents: the HDAC inhibitor sodium butyrate(SB), the demethylating agent 5-Aza-2'-deoxycytidine(5-aza-DC), and radiation. We then estimated the percentage of the cell survival using the XTT method and experimented to determine if there was an augmentation in the therapeutic effect by using different combinations of the two or three of the treatment methods.</p> <p>Results</p> <p>After treatment of each cell lines with 5-aza-DC, SB and 6 grays of radiation, we observed that the survival fraction was lower after the treatment with 5-aza-DC or SB than with radiation alone in RKO and MCF-7 cell lines(p < 0.001). The survival fraction was lowest when the two agents, 5-aza-DC and SB were combined with radiation in both RKO and MCF-cell lines.</p> <p>Conclusion</p> <p>In conclusion, 5-aza-DC and SB can enhance radiosensitivity in both MCF-7 and RKO cell lines. The combination effect of a demethylating agent and an HDAC inhibitor is more effective than that of single agent treatment in both breast and colon cancer cell lines.</p

    Mannosylated-serum albumin nanoparticle imaging to monitor tumor-associated macrophages under anti-PD1 treatment

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    Background Immune checkpoint inhibitors such as anti-programmed cell death protein 1 (PD1) block tumor growth by reinvigorating the immune system; however, determining their efcacy only by the changes in tumor size may prove inaccurate. As the immune cells including macrophages in the tumor microenvironment (TME) are associ‑ ated with the response to anti-PD1 therapy, tumor-associated macrophages (TAMs) imaging using nanoparticles can noninvasively provide the immune enrichment status of TME. Herein, the mannosylated-serum albumin (MSA) nano‑ particle was labeled with radioactive isotope 68Ga to target the mannose receptors on macrophages for noninvasive monitoring of the TME according to anti-PD1 therapy. Results B16F10-Luc and MC38-Luc tumor-bearing mice were treated with anti-PD1, and the response to anti-PD1 was determined by the tumor volume. According to the fow cytometry, the responders to anti-PD1 showed an increased proportion of TAMs, as well as lymphocytes, and the most enriched immune cell population in the TME was also TAMs. For noninvasive imaging of TAMs as a surrogate of immune cell augmentation in the TME via anti-PD1, we acquired [ 68Ga] Ga-MSA positron emission tomography. According to the imaging study, an increased number of TAMs in responders at the early phase of anti-PD1 treatment was observed in both B16F10-Luc and MC38-Luc tumorbearing mice models. Conclusion As representative immune cells in the TME, non-invasive imaging of TAMs using MSA nanoparticles can refect the immune cell enrichment status in the TME closely associated with the response to anti-PD1. As non-inva‑ sive imaging using MSA nanoparticles, this approach shows a potential to monitor and evaluate anti-tumor response to immune checkpoint inhibitors.This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Education (NRF-2020R1A6A3A13069409), the Korean government the Ministry of Science, ICT and Future Planning (2020R1A2C2010202, 2020R1A4A2002903, 2020M3A9B6038086, 2021M2E7A2079570, 2021R1A2C3009427, 2022M3E5F2018261), and the Ministry of Health and Welfare (HI19C0339, HN22C0644). This study also was carried out by the research fund supported by the fund project of Park Yang Sook - Chung Yung Ho in Seoul National University

    Effect of chitinase- 3- like protein 1 on glucose metabolism: In vitro skeletal muscle and human genetic association study

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    We investigated the effect of chitinase- 3- like protein 1 (CHI3L1) on glucose metabolism and its underlying mechanisms in skeletal muscle cells, and evaluated whether the observed effects are relevant in humans. CHI3L1 was associated with increased glucose uptake in skeletal muscles in an AMP- activated protein kinase (AMPK)- dependent manner, and with increased intracellular calcium levels via PAR2. The improvement in glucose metabolism observed in an intraperitoneal glucose tolerance test on male C57BL/6J mice supported this association. Inhibition of the CaMKK was associated with suppression of CHI3L1- mediated glucose uptake. Additionally, CHI3L1 was found to influence glucose uptake through the PI3K/AKT pathway. Results suggested that CHI3L1 stimulated the phosphorylation of AS160 and p38 MAPK downstream of AMPK and AKT, and the resultant GLUT4 translocation. In primary myoblast cells, stimulation of AMPK and AKT was observed in response to CHI3L1, underscoring the biological relevance of CHI3L1. CHI3L1 levels were elevated in cells under conditions that mimic exercise in vitro and in exercised mice in vivo, indicating that CHI3L1 is secreted during muscle contraction. Finally, similar associations between CHI3L1 and metabolic parameters were observed in humans alongside genotype associations between CHI3L1 and diabetes at the population level. CHI3L1 may be a potential therapeutic target for the treatment of diabetes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162777/2/fsb220907.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162777/1/fsb220907_am.pd
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