Steam reforming of methanol over a commercial Cu/ZnO/Al2O3 catalyst was studied at atmospheric pressure and in a temperature range between 160 and 260 DGC. The reaction rate depended upon methanol ...and hydrogen partial pressures, and was independent of the partial pressures of carbon oxides and water, which was in excess of the methanol partial pressure. Small amounts of carbon monoxide, less than 1 % in the product gas, were formed at high temperatures; the amounts were well below the equilibrium amounts of reverse water-gas-shift reaction (RWGS). This was in support of the reaction sequence of methanol steam reforming followed by the RWGS. A power-law and a Langmuir-Hinselwood rate expression were developed for the reforming reaction by fitting the expressions to the experimental data. As the data were found to be affected by internal diffusion at high temperatures, the effectiveness factor of the catalyst particle was estimated in the fitting in order to obtain the intrinsic kinetics. Details of the estimation of the factor are elucidated. In order to predict a non-zero, finite rate in the absence of hydrogen, the hydrogen partial pressure term in the power-law expression was corrected by a fitted constant to avoid an infinite reaction rate, since the exponent of the hydrogen partial pressure was a negative number due to the hydrogen inhibition effect in the reforming; in the reaction mechanism for the Langmuir-Hinselwood expression, it was necessary to assume two different kinds of active sites on the catalyst: one for adsorbed methoxy and the other for adsorbed hydrogen. In addition, an excellent fitting of the data by the Langmuir-Hinselwood expression indicates that dehydrogenation of the adsorbed methoxy to the adsorbed oxymethylene is the rate-determining step (RDS), and that adsorption of all the species other than methoxy and hydrogen on the active sites is negligible.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The management of benign intraductal papilloma diagnosed on core needle biopsy (CNB) remains unclear. This study was designed to evaluate factors predicting malignancy in patients diagnosed with ...benign papilloma without atypia at ultrasound-guided CNB and to develop a scoring system predicting malignancy based on clinical, radiological and pathological factors on further excisional biopsy.
The study enrolled patients diagnosed with benign papillomas (including benign and atypical papillary lesions) at CNB. Multivariate analysis was used to identify relevant clinical, radiological and pathological factors that may predict malignancy.
A total of 520 CNBs were diagnosed with benign or atypical papilloma. Of these, 452 were benign papilloma without atypia. Of the 250 lesions subsequently excised surgically from 234 women, 17 (6.8%) were diagnosed with malignancy. Multivariate analysis revealed that bloody nipple discharge, size on imaging ≥15 mm, BI-RADS≥4b, peripheral location and palpability were independent predictors of malignancy. A scoring system was developed based on logistic regression models and beta coefficients for each variable. The area under the ROC curve was 0.947 (95% CI: 0.913–0.981, p < 0.001) and a negative predictive value was 100%. In a validation set of 62 patients, an area under the ROC curve was 0.926 (95% CI: 0.857–0.995, p < 0.001).
A scoring system predicting malignancy in patients diagnosed by CNB with benign papilloma without atypia was developed. This system was able to identify a subset of patients with lesions likely to be benign, indicating that imaging follow-up rather than surgical excision may be appropriate.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this study, we conducted a survey targeting 191 physical therapists (PTs) and 159 occupational therapists (OTs) in South Korea to explore attitudes toward virtual rehabilitation. Utilizing the ...Korean version of the ADOPT VR by Glegg et al., OT exhibited significantly more experience with virtual reality (VR) and active video games (AVG) than PT. Therapists with VR/AVG experience scored significantly higher in most categories, and the scores in each category were significantly correlated with the Behavioral Intention category, reflecting the willingness to use VR/AVG. The biggest barriers identified were insufficient funds and setup assistance for the equipment. Differences in responses between the groups with and without VR/AVG experience were most prominent in terms of lack of interest and funding. Therapists' attitudes, perceptions, and intentions toward VR/AVG are crucial factors in the establishment and implementation of VR/AVG; thus, the results of this study provide valuable evidence for future policies related to VR/AVG in rehabilitation medicine.
Bacterial peptidoglycans (PGNs) are recognized by the host's innate immune system. This process is mediated by the NOD/CARD family of proteins, which induces inflammation by activating nuclear factor ...(NF)-κB. Excessive activation of monocytes by Shigella flexneri PGN (flexPGN) leads to serious inflammatory diseases such as intestinal bowel diseases (IBD) and Crohn's disease. In this study, we examined whether Lactobacillus plantarum lipoteichoic acid (pLTA) could attenuate the pro-inflammatory signaling induced by flexPGN in human monocytic THP-1 cells. Compared to control THP-1 cells, pLTA-tolerant cells showed a significant reduction in TNF-α and IL-1β production in response to flexPGN. We also examined the inhibition of NF-κB and the activation of mitogen-activated protein kinase (MAPK) in pLTA-tolerant cells. We found that the expression of NOD2 in pLTA-tolerant cells was down-regulated at the mRNA and protein levels, suggesting that pLTA is a potent modulator of the pro-inflammatory NOD2-related signaling pathways induced by flexPGN. Together, these data indicate that pLTA induces cross-tolerance against flexPGN. Notably, these effects are related not only to IL-1 signaling, which is known to play a role in LPS tolerance, but also to NOD-Rick signaling. This study provides insight into how commensal microflora may contribute to homeostasis of the host intestinal tract.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A series of Cu–ZrO2 catalysts with Cu content in the range of 10–70 at.% Cu (=100×Cu/(Cu+Zr)) were prepared by coprecipitation, and their performances were tested for the water-gas-shift (WGS) ...reaction. The activity of the catalyst increased with Cu loading and, depending on the loading, the activity was comparable to or better than the activity of a conventional Cu–ZnO–Al2O3 catalyst at low temperatures below 473 K. Characterization of the catalysts revealed that the amount of Cu+ present on the catalyst surface, after being reduced by a H2 mixture at 573 K, was well correlated with the activity of the catalyst, indicating that the Cu+ species were the active sites of the WGS reaction. The easy redox between Cu2+ and Cu+ during the WGS reaction was considered to be responsible for the high activity of Cu–ZrO2 at low temperatures. A reaction mechanism based on the redox was proposed.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
6.
양파(Allium cepa L.) 유전자원의 Flavonol 배당체 조성 및 함량 이정로(Jung-Ro Lee); 이민기(Min-Ki Lee); 김헌웅(Heon-Woong Kim) ...
Korean journal of crop science,
09/2014, Volume:
59, Issue:
3
Journal Article
Peer reviewed
Open access
Flavonols as a major kind of plant secondary metabolites are known for health-promoting compounds in onions (Allium cepa L.). The objectives of this study are to determine profiles of flavonol ...glycosides in different 75 onion accessions. A total of five flavonols (quercetin 3,4'- diglucoside, Q34'diG; quercetin 3-glucoside, Q3G; quercetin 4'-glucoside, Q4'G; isorhamnetin 4'-glucoside, I4'G; quercetin, Q) were identified from onion accessions. In positive ion mode using LC-ESI-MS, individual flavonols were confirmed from one and two glycosylation binding with aglycone such as quercetin and isorhamnetin. Total flavonol contents were distributed in white onion (range of 0.18-6.47 mg/g DW) and purple onion accessions (range of 2.39-6.47 mg/g), respectively. The mean of flavonol contents in purple onion (4.41 mg/g) showed 1.4-fold higher than white onion (3.23 mg/g). The Q34'diG and Q4'G were considered as the major compounds of flavonol glycosides in onion accessions.
In the present investigation, glucosinolate content was identified and quantified in 210 accessions of Korean leaf mustard (
Brassica juncea
var.
integrifolia
) by a liquid chromatography (LC) with ...electrospray ionization (ESI) coupled with a positive-mode ion trap tandem mass spectrometry (LC–ESI–MS/MS). Eleven individual GSLs including two new compounds were identified in the accessions using desulfo-glucosinolates (DS-GSLs) LC–MS library, and they were elucidated by interpreting the fragmentation data (M + H-glucose
+
) obtained. The newly identified GSLs contained aliphatic and hydroxyl functional group in their back bone were named as 1-ethyl-2-hydroxyethyl DS-GSLs (glucosisautricin) or 2-hydroxy-2-methylpropyl DS-GSLs (glucoconringiin) and 3,4,5-trimethoxybenzyl DS-GSLs, respectively. Among all tested accessions, the total DS-GSLs content was found to be varied between 5.3 and 23.2 mg/g dry weight (DW) with an average of 13.0 mg/g DW in the germplasm. Each individual DS-GSLs component was found in decreasing order of sinigrin (41.7 %) >glucoiberverin (21.7 %) >gluconasturtiin (12.6 %) >glucobarbarin (10.0 %) >glucoiberin (5.1 %) >glucocheirolin (3.6 %) >glucobrassicanapin (2.6 %) >gluconapin (2.1 %), and >glucobrassicin (0.6 %). Interestingly, sinigrin and gluconasturtiin were present in higher content, and progoitrin was not detected significantly in the germplasm of Korean leaf mustard. In particular, accession K046197 (purple) was found to show highest total DS-GSL content (23.2 mg/g DW).
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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