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China Medical Abstracts(Internal Medicine) 2024年第1期41卷 12-13页

作者：张远哲 Basic Med coll Guizhou TCM UnivGuiyang 550025

Objective To investigate the effects of the Aconiti lateralis Radix Praeparata-Cinnamomi Cortex (ALRP-CC)compound on the expression of intestinal neurotransmitters and stem cell factor (SCF),c-kitprotooncogeneprotein (c-Kit) in slow transit constipation (STC) rats with Yang deficiency syndrome,and to explore its mechanism of action for improving intestinal motility.

关键词： Radix motility rats

Cable coupling response in metal cavity under X-ray irradiation

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-11页

作者： Zhang, Mao-Xing Yuan, Lan-Feng Meng, Cui Liu, Yi-Nong Tsinghua Univ Dept Engn Phys Beijing 100084 Peoples R China Minist educ Lab Particle & Radiat Imaging Beijing 100084 Peoples R China Zhejiang Univ Coll Elect Engn Hangzhou 310007 Peoples R China

This study investigates the coupling response of cables inside a metal cavity under X-ray irradiation using the finite-difference time-domain method, particle simulation method, and transmission-line equation to solve the electromagnetic field inside the cavity and load voltage at the cable terminal under X-ray excitation. The results show that under a strong ionizing radiation environment of 1J/cm2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$educ\,{\hbox {J/cm}{2}}$$\end{document}, a strong electromagnetic environment is generated inside the cavity. The cable shielding layer terminal couples a voltage of 15.32 V, whereas the core wire terminal couples a voltage of 0.31 V. Under strong X-ray irradiation, the metal cavity not only fails to provide electromagnetic shielding, but also introduces new electromagnetic interference. This study also provides a method for reducing the number of emitted electrons by adding low-Z materials, which can effectively reduce the coupled electric field and voltage.

关键词： Ionizing radiation Metal cavity System-generated electromagnetic pulse Transmission-line model SIMULATION CODE EQUATIONS IEMP

Experimental study of cryogenic treatment of Karaganda coal samples

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PETROLEUM RESEARCH 2024年第3期9卷 359-368页

作者： Wang, Lei Yan, Xinchuang Sarmalayev, Iliyas Cha, Minsu Zhang, Dichuan Hazlett, Randy D. Chengdu Univ Technol Coll Energy State Key Lab Oil & Gas Reservoir Geol & Exploitat Chengdu 610059 Peoples R China Xian Shiyou Univ Engn Res Ctr Dev & Management Low Ultralow Permeab Minist Educ Xian 710065 Peoples R China Nazarbayev Univ Petr Engn Dept Astana 010000 Kazakhstan Jeju Natl Univ Dept Civil Engn Jeju 62343 South Korea Nazarbayev Univ Dept Civil & Environm Engn Astana 010000 Kazakhstan

Karaganda Coal Basin bears the largest undeveloped reserve of coalbed methane (CBM) in Kazakhstan, which lacks water resources for implementing large-volume hydraulic fracturing. Cryogenic fracturing utilizing liquid nitrogen (LN2) has been trialled in fields and is a waterless fracturing technique under intensive research these days. This study aimed to evaluate the cryogenic treatment efficacy of Karaganda coal samples as well as to understand the coal permeability evolution during the thawing period. X-ray fluorescent spectrometry (XRF) and microscope imaging identified the compositional and structural heterogeneities of coal specimens mined from different interlayers. Acoustic emission test, permeability measurement, and microscope imaging comparatively characterized the dry coal structure alteration before and after immersion into LN2. Cryogenic treatment slowed down the S-wave velocity through coal specimens, enhanced permeability by over 65 % after temperature recovery as well as created new fractures, enlarged existing ones, and spalled coal particles. Dynamic permeability evolution against temperature rise during the thawing process has been successfully captured for the first time. Overall, the experimental measurements support that the LN2 cryogenic fracturing technique would be effective in stimulating coalbeds for CBM production in Karaganda Coal Basin. (c) 2024 The Authors. Publishing services provided by Elsevier B.V. on behalf of KeAi Communication Co. Ltd. This is an open access article under the CC BY license .

关键词： Cryogenic treatment Karaganda coal Dynamic permeability Acoustic emission Microscopic image XRF composition LIQUID-NITROGEN

Effects of blueberry on hepatic fibrosis and transcription factor Nrf2 in rats

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World Journal of Gastroenterology 2010年第21期16卷 2657-2663页

作者： Wang, Yu-Ping Cheng, Ming-Liang Zhang, Bao-Fang Mu, Mao Wu, Jun Guiyang Med coll Dept Infect Dis Guiyang 550004 Guizhou Prov Peoples R China

AIM:To investigate the effects of blueberry on hepatic fibrosis and NF-E2-related factor 2(Nrf2) transcription factor in ***:Forty-five male Sprague-Dawley rats were randomly divided into control group(A);CCl4-induced hepatic fibrosis group(B);blueberry prevention group(C);Dan-shao-hua-xian capsule(DSHX) prevention group(D);and blueberry + DSHX prevention group(E).Liver fibrosis was induced in rats by subcutaneous injection of CCl4 and a high-lipid/low-protein diet for 8 wk(except the control group).The level of hyaluronic acid(HA) and alanine aminotransferase(ALT) in serum was *** activity of superoxide dismutase(SOD),glutathione-S-transferase(GST) and malondialdehyde(MDA) in liver homogenates was *** degree of hepatic fibrosis was evaluated by hematoxylin and eosin and Masson *** of Nrf2 and NADPH quinone oxidoreductase 1(Nqo1) was detected by real-time reversed transcribed-polymerase chain reaction,immunohistochemical techniques,and western ***:Compared with group B,liver indices,levels of serum HA and ALT of groups C,D and E were reduced(liver indices:0.038 ± 0.008,0.036 ± 0.007,0.036 ± 0.005 vs 0.054 ± 0.009,P<0.05;HA:502.33 ± 110.57 ng/mL,524.25 ± 255.42 ng/mL,499.25 ± 198.10 ng/mL vs 828.50 ± 237.83 ng/mL,P<0.05;ALT:149.44 ± 16.51 U/L,136.88 ± 10.07 U/L,127.38 ± 11.03 U/L vs 203.25 ± 31.62 U/L,P<0.05),and SOD level was significantly higher,but MDA level was lower,in liver homogenates(SOD:1.36 ± 0.09 U/mg,1.42 ± 0.13 U/mg,1.50 ± 0.15 U/mg vs 1.08 ± 0.19 U/mg,P<0.05;MDA:0.294 ± 0.026 nmol/mg,0.285 ± 0.025 nmol/mg,0.284 ± 0.028 nmol/mg vs 0.335 ± 0.056 nmol/mg,P<0.05).Meanwhile,the stage of hepatic fibrosis was significantly weakened(P<0.05).Compared with group A,the activity of GST liver homogenates and expression levels of Nrf2 and Nqo1 in group B were elevated(P<0.05).The expression level of Nrf2 and Nqo1 in groups C,D,and E were increased as compared with group B,but the difference was not significant

关键词： Blueberry Hepatic fibrosis NF-E2-related factor 2 NADPH quinone oxidoreductase 1 GlutathioneS-transferase

Application of a neural network model with multimodal fusion for fluorescence spectroscopy

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-14页

作者： Tang, Lin Zhou, Shuang Shi, Kai-Bo Shen, Hong-Tao You, Lei Chengdu Univ Coll Elect Informat & Elect Engn Chengdu 610106 Peoples R China Guangxi Normal Univ Guangxi Key Lab Nucl Phys & Nucl Technol Guilin 541004 Peoples R China Anhui Univ Natl Engn Res Ctr Agroecol Big Data Anal & Applica Hefei 230039 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore Panzhihua Univ Vanadium & Titanium Resource Comprehens Utilizat K Panzhihua 617000 Peoples R China Chengdu Normal Univ Inst Higher Educ Sichuan Prov Key Lab Interior Layout Optimizat & Secur Chengdu 611130 Peoples R China

In energy-dispersive X-ray fluorescence spectroscopy, the estimation of the pulse amplitude determines the accuracy of the spectrum measurement. The error generated by the amplitude estimation of the pulse output distorted by the measurement system leads to false peaks in the measured spectrum. To eliminate these false peaks and achieve an accurate estimation of the distorted pulse amplitude, a composite neural network model is proposed, which embeds long and short-term memory (LSTM) into the UNet structure. The UNet network realizes the fusion of pulse sequence features and the LSTM model realizes pulse amplitude estimation. The model is trained using simulated pulse datasets with different amplitudes and distortion times. For the pulse height estimation, the average relative error of the trained model on the test set was approximately 0.64%, which is 27.37% lower than that of the traditional trapezoidal shaping algorithm. Offline processing of a standard iron source further validated the pulse height estimation performance of the UNet-LSTM model. After estimating the amplitude of the distorted pulses using the model, the false peak area was reduced by approximately 91% over the full spectrum and was corrected to the characteristic peak region of interest (ROI). The corrected peak area accounted for approximately 1.32% of the characteristic peak ROI area. The results indicate that the model can accurately estimate the height of distorted pulses and has substantial corrective effects on false peaks.

关键词： UNet Long- and short-term memory Pulse distortion Pulse height estimation Fluorescent spectroscopy

Insights into the Discrepancy between Single Molecule Experiments

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Communications in Theoretical Physics 2019年第6期71卷 753-763页

作者： Qian Zhou Min Zhang Yang-Tao Fan Yu-Kang Wang Lin Bao Guang-Ju Zhao Hu Chen Yan-Hui Liu guizhou Univ Coliege Phys Guiyang 550025 Guizhou Peoples R China guizhou Univ Coll Big Data & Informat Engn Guiyang 550025 Guizhou Peoples R China Xiamen Univ Dept Phys Xiamen 361005 Fujian Peoples R China Xiamen Univ Pen Tung Sah Inst Micronano Sci & Technol Xiamen 361005 Fujian Peoples R China

Sharp bending as one of the mechanical properties of double-stranded DNA(dsDNA) on the nanoscale is essential for biological functions and processes. Force sensors with optical readout have been designed to measure the forces inside short, strained loops composed of both dsDNA and single-stranded DNA(ssDNA). Recent FRET singlemolecule experiments were carried out based on the same force sensor design, but provided totally contrary results. In the current work, Monte Carlo simulations were performed under three conditions to clarify the discrepancy between the two experiments. The criterion that the work done by the force exerted on dsDNA by ssDNA should be larger than the nearest-neighbor(NN) stacking interaction energy is used to identify the generation of the fork at the junction of dsDNA and ssDNA. When the contour length of dsDNA in the sensor is larger than its critical length, the fork begins to generate at the junction of dsDNA and ssDNA, even with a kink in dsDNA. The forces inferred from simulations under three conditions are consistent with the ones inferred from experiments, including extra large force and can be grouped into two different states, namely, fork states and kink states. The phase diagrams constructed in the phase space of the NN stacking interaction energy and excited energy indicate that the transition between the fork state and kink state is difficult to identify in the phase space with an ultra small or large number of forks, but it can be detected in the phase space with a medium number of forks and kinks.

关键词： force sensor Monte Carlo simulation kink structure fork structure nearest-neighbouring stacking interaction energy

Effect of the Transient Response in Si/Ge Parallelizing PN Junction

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Journal of Materials Science & Technology 1999年第4期15卷 383-383页

作者： Weiqi HUANGt and Chaogang CHEN(Department of Physics, guizhou educational college, Guiyan 550003, China)Ergang CHEN(Department of Physics, Yunnan University, Kunming 650091, China)To whom correspondence should be addressed guizhou educ coll Dept Phys Guiyang 550003 Peoples R China Yunnan Univ Dept Phys Kunming 650091 Peoples R China

There are some new results about photovoltaic transient response in the new effect. We suggest a theoretical model to explain the effect reasonably. The theoretical calculation results agree with that in experiments.

关键词： PN Si Ge Effect of the Transient Response in Si/Ge Parallelizing PN Junction

Detection of hydroxyl radical in plasma reaction on toluene removal

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Journal of Environmental Sciences 2008年第12期20卷 1429-1432页

作者： Guo Yufang Liao Xiaobin Ye Daiqi Guangzhou Univ Guangzhou Higher Educ Mega Ctr Coll Environm Sci & Engn Guangzhou 510006 Guangdong Peoples R China S China Univ Technol Guangzhou Higher Educ Mega Ctr Coll Environm Sci & Engn Guangzhou 510006 Guangdong Peoples R China

A new method was introduced to detect the concentration of OH radical in dielectric barrier discharge(DBD)reaction.A film, which was impregnated with salicylic acid,was used to detect OH radical in plasma reaction at room temperature and atmospheric *** acid reacts with OH radical and produces 2,5-dihydroxybenzoic acid(2,5-DHBA).Then,a high performance liquid chromatography(HPLC)was carried out to detect the concentration of 2,***,OH radical in nonthermal plasma reaction could be...

关键词： OH radical detection nonthermal plasma toluene

Chemoenzymatic Synthesis of Ramosetron Hydrochloride

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Chemical Research in Chinese Universities 2012年第1期28卷 70-72页

作者： LIU Qing-wen1 , XU Hao1, TIAN Hua1, ZHENG Liang-yu2 and ZHANG Suo-qin1 1. college of Chemistry, 2. Key Laboratory for Molecular Enzymology and Engineering, Ministry of education, Jilin University, Changchun 130012, P. R. China Jilin Univ Minist Educ Key Lab Mol Enzymol & Engn Changchun 130012 Peoples R China Jilin Univ Minist Educ Coll Chem Changchun 130012 Peoples R China

A new method for the synthesis of ramosetron hydrochloride, the most wildly used 5-HT3 receptor antagonist, was reported. The intermediate 8 was obtained in a high e.e. value via lipase catalyzed hydrolytic kinetic resolution. Then enantiomerically pure ramosetron hydrochloride was synthesized in two steps with excellent yield （the total yield is 24.6%）. The method provides a new environment friendly and atom economy way to synthesize enantiomerically pure ramosetron.

关键词： Ramosetron hydrochloride Chemical enzymatic synthesis Atom economy

The radio structure of BL Lac object S5 2007+777

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 187-190页

作者： WU ZhongZu1,3,GU MinFeng2 & CHEN YongJun2 1 college of Science,guizhou University,Guiyang 550025,China 2 Key Laboratory for Research in Galaxies and Cosmology,Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 200030,China 3 NAOC-GZU Sponsored Center for Astronomy,guizhou University,Guiyang 550025,China guizhou Univ Coll Sci Guiyang 550025 Peoples R China Chinese Acad Sci Shanghai Astron Observ Key Lab Res Galaxies & Cosmol Shanghai 200030 Peoples R China guizhou Univ NAOC GZU Sponsored Ctr Astron Guiyang 550025 Peoples R China

BL Lac object S5 2007+777 has been classified as a HYMOR(Hybrid Morphology radio source) for its hybrid FR I and FR II radio *** is one of four BL Lac objects with a kpc scale extended X-ray *** this paper,we searched the unpublished European VLBI Network(EVN) archived high resolution data for this source,and present the high resolution radio *** EVN images all show a core-jet structure in 1.6,5 and 8 *** combination with the VLA data in the literature,we found position angle differences(△PA) of about 10°-20° between pc and kpc scale jet *** brightness temperature estimated from multi-band EVN images are around 1011.2-1011.8 K,from which the Doppler factor ranges from 3.2 to *** found significant flux variations of the radio core in 1.6 and 5 GHz,from which we derived the variability in brightness temperature Tvar to be 1013.6 K and 1014.0 K,corresponding to the Doppler factors of 9.3 and 12.4,respectively.

关键词： active galactic nuclei VLBI BL Lac objects