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71.
The roots of Peucedanum japonicum (Apiaceae) have been used as an alternative to the roots of Saposhnikovia divaricata (Apiaceae) to treat common cold-related symptoms in Korea. However, a variety of Peucedanum species, including the roots of P. praeruptorum or Angelica decursiva (=P. decursivum), have been used to treat phlegm–heat-induced symptoms in China. Hence, as there are differences in the medicinal application of P. japonicum roots between Korea and China, chemotaxonomic classification of P. japonicum was evaluated. Sixty samples derived from P. japonicum, P. praeruptorum, A. decursiva, and S. divaricata were phylogenetically identified using DNA barcoding tools, and chemotaxonomic correlations among the samples were evaluated using chromatographic profiling with chemometric analyses. P. japonicum samples were phylogenetically grouped into the same cluster as P. praeruptorum samples, followed by S. divaricata samples at the next cluster level, whereas A. decursiva samples were widely separated from the other species. Moreover, P. japonicum samples showed higher chemical correlations with P. praeruptorum samples or A. decursiva samples, but lower or negative chemical correlations with S. divaricata samples. These results demonstrate that P. japonicum is more genetically and chemically relevant to P. praeruptorum or A. decursiva and, accordingly, the medicinal application of P. japonicum might be closer to the therapeutic category of these two species than that of S. divaricata. 相似文献
72.
Hyun-Ju Kim Dong-Kyo Lee Xian Jin Xiangguo Che Sung Ho Ryu Je-Yong Choi 《Experimental & molecular medicine》2022,54(8):1146
Phospholipase D2 (PLD2), a signaling protein, plays a central role in cellular communication and various biological processes. Here, we show that PLD2 contributes to bone homeostasis by regulating bone resorption through osteoclastic cell migration and microtubule-dependent cytoskeletal organization. Pld2-deficient mice exhibited a low bone mass attributed to increased osteoclast function without altered osteoblast activity. While Pld2 deficiency did not affect osteoclast differentiation, its absence promoted the migration of osteoclast lineage cells through a mechanism involving M-CSF-induced activation of the PI3K–Akt–GSK3β signaling pathway. The absence of Pld2 also boosted osteoclast spreading and actin ring formation, resulting in elevated bone resorption. Furthermore, Pld2 deletion increased microtubule acetylation and stability, which were later restored by treatment with a specific inhibitor of Akt, an essential molecule for microtubule stabilization and osteoclast bone resorption activity. Interestingly, PLD2 interacted with the M-CSF receptor (c-Fms) and PI3K, and the association between PLD2 and c-Fms was reduced in response to M-CSF. Altogether, our findings indicate that PLD2 regulates bone homeostasis by modulating osteoclastic cell migration and microtubule stability via the M-CSF-dependent PI3K–Akt–GSK3β axis.Subject terms: Bone, Microtubules 相似文献
73.
Pant HR Nam KT Oh HJ Panthi G Kim HD Kim BI Kim HY 《Journal of colloid and interface science》2011,364(1):107-111
In this work, different fractions of solvent-induced polymer degraded solution were mixed with freshly prepared solution of same polymer, and its effect on fiber morphology of electrospun mats was investigated. Nylon-6 solution in formic acid was allowed to degrade for 3 weeks and different fractions of it were mixed with freshly prepared nylon-6 solution to get the electrospun mats. FE-SEM images of the mats indicated that the a large amount of sub-nanofibers (<50 nm in diameter) in the form of spider-net like structures were achieved by tailoring the amount of solvent degraded polymer solution in the freshly prepared nylon-6 solution. Large quantity of these ultrafine sub-nanofibers present in electrospun nylon-6 mats could increase its hydrophilicity and mechanical strength. The decreased average pore diameter and increased BET surface area of the mat, caused by spider-net like structure, can make it as a potential candidate for air/water filtration. 相似文献
74.
This paper investigates the three-dimensional flow of a Sisko fluid over a bidirectional stretching sheet, in a porous medium. By using the effect of Cattaneo-Christov heat flux model, heat transfer analysis is illustrated. Using similarity transformation the governing partial differential equations are transferred into a system of ordinary differential equations that are solved numerically by applying Nachtsheim-Swigert shooting iteration technique along with the 6-th order Runge-Kutta integration scheme. The effect of various physical parameters such as Sisko fluid, ratio parameter, thermal conductivity, porous medium, radiation parameter, Brownian motion, thermophoresis, Prandtl number, and Lewis number are graphically represented. 相似文献
75.
Park HG Kim MJ Park MK Jung HJ Lee J Choi SH Lee YJ Jeong BS Lee JH Yoo MS Ku JM Jew SS 《The Journal of organic chemistry》2005,70(5):1904-1906
A new Merrifield-resin-derived glycinimine tert-butyl ester (9) was prepared and applied to the enantioselective synthesis of non-natural alpha-amino acids. High enantioselectivities (86 to >99% ee) were accomplished by employing the aldimine linker under phase-transfer alkylation conditions, using 50% aqueous CsOH in toluene/chloroform (7:3) at 0 degrees C in the presence of N-(9-anthracenylmethyl)-O(9)-allylcinchonidium bromide (10 mol %). 相似文献
76.
The purpose of the present study was to assess the general characteristics of images produced by radiolucent and radiopaque materials used for computed tomography scanning of the animal rectum and suggest ideal materials for contrast enhancement between normal and abnormal tissues. The computed tomography system used in this study was 64-multidetector computed tomography. Computed tomography scanning was performed with standard scan parameters for abdominal examination and gemstone spectral image mode using saline, methyl-cellulose, contrast medium, ultrasound gel, and air in addition to radiolucency. Computed tomography values were obtained for each material at different energy levels. Changes in computed tomography values were compared and analyzed. Changes in computed tomography values and volume of each material were examined before and after rectal contrast material administration. Ultrasound gel was found to exhibit a computed tomography value close to the baseline value and a greater degree of contrast, compared with other materials. In image evaluation, methyl-cellulose is considered a useful material in providing contrasting image evidence of rectal diseases. Also, it had a larger volume in the rectum after a computed tomography scan. Thus, methyl-cellulose was a useful contrast medium for computed tomography scan imaging of the rectum. 相似文献
77.
Abstract
The tungsten inert gas (TIG) welding enables to produce high welding qualities. However, it has some problems such as a large distortion and a shallow penetration into the welding parts. To overcome those problems, there have been many studies on A-TIG welding in which active flux and a shield gas are used. The shield gas pressure, velocity, and distribution area are dominant factors in producing better welding condition which can be evaluated by the gas penetration, the gap between the nozzle tip and welding plate and the nozzle shape of the shield gas. In this study, the influences of the shield gas distribution onto the melting efficiency and penetration shape in TIG welding were investigated using a numerical simulation. The gap distances between the nozzle tip and the welding plate were changed 3, 4, 5 mm and two nozzle shapes, convergent parallel (CP) and CDP, were tested. 100% Ar gas was used as the shield gas. CDP type nozzle showed deeper penetrations and higher melting efficiency compared to those of CD type and CP type nozzles. 相似文献78.
79.
Chil-Hoon Doh Nallathamby Kalaiselvi Cheol Wan Park Seong-In Moon Mun-Soo Yun 《Ionics》2004,10(5-6):421-428
Among the variety of alternate anode materials being studied, the research on the exploration of 3d-metal oxide anodes gains
paramount importance in the recent time, as it is bestowed with an easy preparation method and a less complicated decomposition
mechanism. Towards this direction, an attempt to synthesize the compound CoO and to investigate the electrochemical behavior
of the same both individually and in comparison with NiO compounds was made with a view to understand the extent to which
the chosen candidates, viz., CoO and NiO can be exploited as high capacity anodes. Between the two oxides, CoO exhibited a
specific capacity of at least 550 mAh/g, against NiO with an average capacity of ∼330 mAh/g. Also, the magnitude of irreversible
capacity loss and the extent of capacity fade upon cycling corresponding to CoO anode were found to be lesser than NiO anodes.
The enhanced specific capacity values and the better cycleability properties of CoO anodes are believed to be due to the inherent
electrochemical characteristics of the compound. The type and the nature of SEI formed over the electrode surface and the
formation of possible progressive agglomeration of the products of decomposition are expected to be the factors responsible
for the difference in the electrochemical behavior of CoO and NiO anodes. In short, electrochemical characterization of the
individual oxides are studied and probable reasons for the observed difference in the charge-discharge behavior of CoO and
NiO anodes are discussed in this communication. 相似文献
80.
A modal wavelet transform, which overcomes the intrinsic data number limitation of power of two to conventional wavelet transform,
has been applied to analysis of axial and eddy pseudo velocity fields, standard PIV velocity field and experimental PIV measurement.
The modal wavelet transform is compared with the discrete wavelet transform in order to select the optimum basis function
among Neumann, Dirichlet and Green function types basis functions. Consequently, it is verified that Neumann type function
is the best basis because the correlation of Neumann type basis function is higher and the root mean square is lower than
the other basis functions. Also, the decomposition vector patterns by Neumann type are similar to that by conventional Daubechies
basis function of 4th order. 相似文献