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Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao Jian-ping Huang xin-Ru Mu Ji-Dong Yang Yu-Jian Zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

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Berberine Enhances Intestinal Mucosal Barrier Function by Promoting Vitamin D Receptor Activity

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Chinese Journal of Integrative Medicine 2024年第2期30卷 143-151页

作者： HUANG Yong-quan LIU Jia-lin CHEN geng-xin SHEN Dan-ting ZHU Wang CHEN xin-lin LIU Feng-bin HOU Qiu-ke Graduate School Guangzhou University of Chinese MedicineGuangzhou(510405)China Department of Orthopedics the Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou(510006)China Department of Preventive Medicine and Health Statistics Guangzhou University of Chinese MedicineGuangzhou(510006)China Department of Gastroenterology the First Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou(510405)China

Objective:To evaluate if berberine can act on vitamin D receptors(VDR)and thereby regulate the expression of tight junction proteins(TJPs)in irritable bowel syndrome-diarrhea-predominant(IBS-D)***:The newborn rats were induced into IBS-D rat model via neonatal maternal separation combined with acetic acid chemical *** modeling,the model was evaluated and rats were divided into the control group and berberine treatment groups(0.85,1.7 and 3.4 mg/kg,once a day for 2 weeks).The distal colon was obtained and colonic epithelial cells(CECs)were isolated and cultured after IBS-D model *** vitamin D receptor response element(VDRE)reporter gene was determined in the CECs of IBS-D rats to analyze the effect of berberine on the VDRE *** overexpression or silencing technology was used to analyze whether VDR plays a role in promoting intestinal barrier repair,and to determine which region of VDR plays a role in berberine-regulated intestinal ***:The IBS-D rat model was successfully constructed and the symptoms were improved by berberine in a dose-dependent manner(P<0.05).The activity of VDRE promoter was also effectively promoted by berberine(P<0.05).Berberine increased the expression of TJPs in IBS-D CECs(P<0.05).VDR expression was significantly increased after transfection of different domains of VDR when compared to normal control and basic plasmid groups(all P<0.05).RT-qPCR and Western blot results showed that compared with the blank group,expressions of occludin and zonula occludens-1 were significantly higher in VDR containing groups(all P<0.05).Berberine plus pCMV-Myc-VDR-N group exerted the highest expression levels of occludin and zonula occludens-1(P<0.05).Conclusion:Berberine enhances intestinal mucosal barrier function of IBS-D rats by promoting VDR activity,and the main site of action is the N-terminal region of VDR.

关键词： berberine Chinese medicine irritable bowel syndrome-diarrhea-predominant vitamin D receptors intestinal mucosal barrier tight junction proteins

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Microdeletion on Xq27.1 in a Chinese VACTERL-Like Family with Kidney and Anal Anomalies

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Biomedical and Environmental Sciences 2024年第5期37卷 503-510页

作者： LI Min ZHANG Yu Lan ZHANG Kai Li LI ping ping LYU Yu Han LIANG Ya xin YU Yue Department of Gynecology and Obstetrics Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Chinese Academy of Medical Sciences and Peking Union Medical College Beijing HospitalBeijing 100730China The Key Laboratory of Geriatrics Beijing Institute of GeriatricsBeijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China

Objective VATER/VACTERL-like association is associated with adverse pregnancy *** evidence of this disorder is *** this study,we aimed to provide genetic insights to improve the diagnosis of *** We have described a Chinese family in which four members were affected by renal defects or agenesis,anal atresia,and anovaginal fistula,which is consistent with the diagnosis of a VACTERL-like *** and genetic analyses were conducted using genome and exome *** Segregation analysis revealed the presence of a recessive X-linked microdeletion in two living affected individuals,harboring a 196–380 kb microdeletion on Xq27.1,which was identified by familial exome *** sequencing was performed on the affected male,confirming a-196 kb microdeletion in Xq27.1,which included a 28%loss of the CDR-1 *** family members were included in the co-segregation analysis,and only VACTERL-like cases with microdeletions were reported in *** These results suggest that the 196–380 kb microdeletion in Xq27.1 could be a possible cause of the VATER/VACTERL-like ***,further genetic and functional analyses are required to confirm or rule out genetic background as the definitive cause of the VACTERL association.

关键词： Prenatal diagnosis VACTERL whole-genome sequencing whole-exome sequencing X-linked

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Muscovite^(40)Ar/^(39)Ar isotopic dating of pegmatite veins in the Bieyesamas rare metal deposit in the Altay Mountain,xinjiang,northwestern China

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China Geology 2024年第3期7卷 589-591页

作者： geng-biao Qiao ping Wang Xiao-hong Wang Jun-lu Chen Key Laboratory for the Study of Focused Magmatism and Giant Ore Deposits Ministry of Natural ResourcesXi’an 710119China Northwest China Center for Geoscience Innovation Xi’an Center of China Geological SurveyXi’an 710119China Petroleum Exploration and Development Research Institute of PetroChina Changqing Oilfield Company Xi’an 710086China

*** The Altay Orogenic Belt in xinjiang,China is located in the west of the Central Asian Orogenic Belt and in the transition zone between the Siberian Plate and the Kazakhstan-Junggar Plate,extending approximately 500 km in northern xinjiang,China(Fig.1a).The Altay Orogenic Belt has undergone two-way accretion of the Paleozoic crust and the Meso-Cenozoic intracontinental orogeny,leading to the formation of large numbers of intermediate-acid *** than 100000 pegmatite veins have been discovered in the intermediate-acid intrusions,and they constitute an important rare metal metallogenic belt of China(Fig.1b).

关键词： xinjiang dating isotopic

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Unconventional Organic Low-Dimensional Crystals:Diversity and Potential Applications

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CCS Chemistry 2024年第7期6卷 1628-1653页

作者： Jin Feng Mao Sun Ying-xin Ma Zhen-Yu geng Chuan-Zeng Wang Shu-ping Zhuo Shu-Hai Chen Hong-Tao Lin Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000 School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255000 Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123

Organic low-dimensional crystals have garnered escalating interests in the realms of miniaturized optoelectronics and integrated *** continual expansion of molecular systems and improvement in experimental conditions have given rise to unconventional organic low-dimensional crystals,which showcase a variety of appealing structure-dependent properties in the realm of organic semiconductors,owing to their adaptable physicochemical characteristics and exceptional optoelectronics ***,the development of unconventional low-dimensional crystals is filled with abundant possibilities due to their diverse application ***,we present a comprehensive overview of advancements in research on representative cases of unconventional low-dimensional organic crystals,using a systematic and rational structural ***,we have also discussed the existing challenges and future directions,aspiring to deepen understanding and encourage further research exploration in this field.

关键词： organic semiconductor crystal growth precise synthesis noncovalent interaction integrat-ed photonics

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Impact of early refined nursing program on prognosis of middleaged and elderly patients with cognitive dysfunction combined with cerebral infarction

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World Journal of Psychiatry 2024年第7期14卷 1034-1042页

作者： Hui-Lian Xiong Zhi-xin Li xin Lu Yan-Hua Lu ping Zhong Ganzhou City Central Blood Station Ganzhou 341000Jiangxi ProvinceChina Department of Rehabilitation Medicine Ganzhou People's HospitalGanzhou 341000Jiangxi ProvinceChina

BACKGROUND Cerebral infarction is a local or extensive necrosis of brain ***,the corresponding neurological deficits *** incidence of cerebrovascular diseases in China is increasing *** the onset of cerebrovascular disease,the most common sequelae include movement disorders,language disorders,and cognitive *** To investigate the effect of early refined nursing program on the prognosis of middle-aged and elderly patients with cerebral infarction combined with cognitive *** A retrospective study was conducted to divide 60 patients with cerebral infarction and cognitive impairment into an experimental group(n=32)and a control group(n=28).The experimental group received early intensive care every day,and the control group received daily routine *** scores of the Mini-Mental State Examination(MMSE)and the Trail Making Test(TMT),as well as the latency and amplitude of the event-related potential P300,were used as main indicators to evaluate changes in cognitive function,and changes in BDNF,TGF-β,and GDNF expression were used as secondary *** Both groups experienced notable enhancements in MMSE scores,with the experi-mental group demonstrating higher scores than the control group(experimental:28.75±2.31;control:25.84±2.87).Moreover,reductions in TMT-A and TMT-B scores were observed in both groups(experimental:TMT-A 52.36±6.18,TMT-B 98.47±10.23;control:TMT-A 61.48±7.92,TMT-B 112.63±12.55),with the experimental group displaying lower scores.P300 Latency decreased(experimental:270.63 ms±14.28 ms;control:285.72 ms±16.45 ms),while amplitude increased(experimental:7.82μV±1.05μV;control:6.35μV±0.98μV)significantly in both groups,with superior outcomes in the experimental ***,the levels of the growth factors BDNF,TGF-β1,and GDNF surged(experimental:BDNF 48.37 ng/mL±5.62 ng/mL,TGF-β152.14 pg/mL±4.28 pg/mL,GDNF 34.76 ng/mL±3.89 ng/mL;control:BDNF 42.58 ng/mL±4.73 ng/mL,TGF-β146.23 pg/m

关键词： Early refined nursing program Cerebral infraction Cognitive impairment Psychiatry Trajectory test

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Hot deformation behavior and microstructure evolution of GH3536-TiB_(2) composites fabricated by powder metallurgy

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Science China(Technological Sciences) 2024年第7期67卷 2107-2124页

作者： ZHOU ShiPeng WANG Shuai HUANG LuJun ZHANG Rui CHEN xin MENG FanChao CHEN Run SUN FengBo WANG CunYu geng Lin School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Waikato Centre for Advanced Materials and Manufacturing School of EngineeringUniversity of WaikatoHamilton 3240New Zealand State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

The hot deformation behavior and microstructure evolution of GH3536-TiB2composites fabricated by powder metallurgy(PM)were examined in the temperature range of 950–1150℃ and strain rate range of 0.001–1 s^(-1). The hot compression stress-strain curves and the constitutive equation were obtained. In addition, the hot processing map was drawn, which indicated that the appropriate hot working window was 950–1050℃/0.001–0.1 s^(-1)and 1050–1100℃/0.001–0.01 s^(-1). The microstructure analysis showed that the splitting and spheroidization of M3B2led to a decrease in size and volume fraction at 950–1100℃. At 1150℃,the eutectic microstructure of M_(3)B_(2)+ γ was formed due to the dissolution of M_(3)B_(2), which caused macroscopic cracking of the deformed sample. Additionally, the deformation temperature and the strain rate had little effect on the size and volume fraction of M_(3)B_(2). Besides, discontinuous dynamic recrystallization(DDRX) and continuous dynamic recrystallization(CDRX) were found in the deformed microstructure, while the former was dominant. Within the test range of this work, the dynamic recrystallization(DRX) fraction of the deformed composites was high due to the bulging nucleation of numerous interfaces. The DRX grain size increased with increasing deformation temperature or decreasing strain rate. Texture analysis showed that the deformation texture of //compression direction RD existed in the matrix when the deformation temperature was below 1100℃, and the texture type became //RD at 1100℃. Additionally, it was also found that the //RD texture was formed in M3B2under the strain rates of 0.1 and 0.01 s^(-1).

关键词： GH3536 alloy matrix composites powder metallurgy hot deformation behavior microstructure evolution

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Ergodicity of a Special Class of Markov Chains

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Acta Mathematicae Applicatae Sinica 2024年

作者： xin-yu HU ping HE School of Mathematics Shanghai University of Finance and Economics

The paper focuses on the ergodicity of a φ-irreducible Markov chain {X_n, n ≥ 0} that is generated iteratively through the expression Xn+1= f（X_n） + ?n+1. Here, {?_n, n ≥ 1} is a sequence of independent identically distributed centralized random variables, f（·） is an R-valued continuous function, and X0is arbitrary but independent of {?_n, n ≥ 1}. Our main contribution is to provide necessary and sufficient conditions for ergodicity of this special class of Markov chains. We also present a generalized approach for f（·） in the end.

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Helmholtz decomposition with a scalar Poisson equation in elastic anisotropic media

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Petroleum Science 2024年第3期21卷 1597-1610页

作者： xin-Yu Fang Gang Yao Qing-Qing Zheng ping-Min Zhang Di Wu Feng-Lin Niu State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China Unconventional Petroleum Research Institute China University of Petroleum(Beijing)Beijing102249China Department of Mathematics College of ScienceChina University of Petroleum(Beijing)Beijing102249China College of Geophysics China University of Petroleum(Beijing)Beijing102249China Department of Earth Environmental and Planetary SciencesRice UniversityHoustonTX77005UA

P-and S-wave separation plays an important role in elastic reverse-time *** can reduce the artifacts caused by crosstalk between different modes and improve image *** addition,P-and Swave separation can also be used to better understand and distinguish wave types in complex *** present,the methods for separating wave modes in anisotropic media mainly include spatial nonstationary filtering,low-rank approximation,and vector Poisson *** of these methods require multiple Fourier transforms or the calculation of large matrices,which require high computational costs for problems with large *** this paper,an efficient method is proposed to separate the wave mode for anisotropic media by using a scalar anisotropic Poisson operator in the spatial *** 2D problems,the computational complexity required by this method is 1/2 of the methods based on solving a vector Poisson ***,compared with existing methods based on pseudoHelmholtz decomposition operators,this method can significantly reduce the computational *** examples also show that the P and S waves decomposed by this method not only have the correct amplitude and phase relative to the input wavefield but also can reduce the computational complexity significantly.

关键词： Anisotropic media Scalar anisotropic Poisson equation Improved elastic wavefield decomposition

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Targeted DNA N^(6)-methyladenine editing by dCas9 fused to METTL4 in the lepidopteran model insect Bombyx mori

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Insect Science 2024年第2期31卷 646-650页

作者： Feng Chen Hao Guo Weiqun Lan Mingyi Zhou Wenjng geng Guanwang Shen ping Lin Qingyou Xia ping Zhao Zhiqing Li Integrative Science Center of Germplasm Creation in Western China(CHONGQING)Science City Biological Science Research CenterSouthwest UniversityChongqingChina Chongqing Key Laboratory of Sericultural Science Chongqing Engineering and Technology Research Center for Novel Silk MaterialsSouthwest UniversityChongqingChina

Dear Editor,N^(6)-Methyladenine(6mA)DNA modification is an important epigenetic mechanism with roles in regulating gene expression,nucleosome positioning,DNA damage repair,and cell cycle progression(Heyn&Esteller,2015;Luo et al.,2015;Boulias&Greer,2022).Despite progress in understanding the biological functions of 6mA,the contribution of individual 6mA installations on site-specific target genes is largely unknown,and therefore deciphering the molecular mechanism of 6mA in target gene expression has been difficult.

关键词： adenine fused Bombyx

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