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N-acetylcysteine ameliorates erectile dysfunction in rats with hyperlipidemia by inhibiting oxidative stress and corpus cavernosum smooth muscle cells phenotypic modulation

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Asian Journal of Andrology 2024年第1期26卷 99-106页

作者： Wei ding Jun-Hong Fan Li-Ren zhong Nan-xiong Wang Lu-Hao Liu Hai-bo Zhang Li Wang Ming-Qiang Wang Bing-Lin he An-Yang Wei Department of Urology The First Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang 550002China Department of Urology Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhou 510000China Department of Urology Nanfang HospitalSouthern Medical UniversityGuangzhou 510000China Department of Urology Shenzhen Immigration Inspection General Station HospitalShenzhen 518000China Department of Organ Transplantation The Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510000China Department of Endocrinology The First Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang 550002China

Hyperlipidemia is a major risk factor for erectile dysfunction(ED).Oxidative stress and phenotypic modulation of corpus cavernosum smooth muscle cells(CcSMCs)are the key pathological factors of ED.N-acetylcysteine(NAC)can inhibit oxidative stress;however,whether NAc can alleviate pathological variations in the corpus cavernosum and promote erectile function recovery in hyperlipidemic rats remains unclear.A hyperlipidemia model was established using 27 eight-week-old male Sprague-Dawley(SD)rats fed a high-fat and high-cholesterol diet(hyperlipidemic rats,HR).In addition,9 male SD rats were fed a normal diet to serve as controls(NC).HR rats were divided into three groups:HR,HR+normal saline(NS),and HR+NAC(n=9 for each group;NS or NAc intraperitoneal injections were administered daily for 16 weeks).Subsequently,the lipid profiles,erectile function,oxidative stress,phenotypic modulation markers of ccsMCs,and tissue histology were *** experimental results revealed that erectile function was significantly impaired in the HR and HR+NS groups,but enhanced in the HR+NAC *** lipid levels,over-activated oxidative stress,and multi-organ lesions observed in the HR and HR+NS groups were improved in the HR+NAC ***,the HR group showed significant phenotypic modulation of CCSMCs,which was also inhibited by NAC *** report focuses on the therapeutic effect of NAc in restoring erectile function using a hyperlipidemic rat model by preventing CcSMC phenotypic modulationand attenuating oxidativestress.

关键词： erectile dysfunction hyperlipidemia N-acetylcysteine oxidative stress henotypic modulation

Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

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Journal of Iron and Steel Research International 2024年第2期31卷 519-530页

作者： ding-qian Dong Feng-yuan he Xin-hui Chen Hui Li Kai-hua Shi Hui-wen xiong Xin Xiang Li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

Determinants of saturation magnetic flux density in Fe-based metallic glasses: insights from machine-learning models

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Rare Metals 2024年第10期43卷 5256-5267页

作者： Jie xiong bo-wen Bai Hao-Ran Jiang Angeles Faus-Golfe Materials Genome Institute Shanghai University Institute of Special Environments Physical Sciences Harbin Institute of Technology Laboratoire de Physique des 2 Infinis Irene Joliot-Curie (IJCLab) CNRS-IN2P3Universite′Paris-Saclay

Fe-based metallic glasses have garnered significant attention due to their low coercivity force and core loss. Enhancing the saturation magnetic flux density(Bs) of Fe-based metallic glasses is crucial for their industry applications. This work constructed a dataset comprising330 training data and 157 test data. The support vector regression model surpassed the tree-based ensemble models in the test set and demonstrated comparable accuracy to the tree-based ensemble models in the training set. Additionally, we proposed an indicator for Bsbased on symbolic regression. This newly proposed indicator exhibits a Pearson correlation coefficient exceeding 0.92 with Bs. The present work provides a simple and accurate formula for predicting the Bsof Fe-based amorphous alloys, demonstrating the effectiveness of machine learning approaches in discovering novel soft magnetic materials.

关键词： Fe-based metallic glasses Machine learning Saturation magnetic flux density Symbolic regression

A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

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Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan he Weidong Wang Zhi ding wen he Yong he Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle ***,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly ***,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating *** remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional *** utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS *** addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical *** work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial ***,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

Thiazoloisoindigo-based Polymer Semiconductors: Synthesis,Structure-Property Relationship, Charge Carrier Polarity, and Field-Effect Transistor Performance

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Chinese Journal of Polymer Science 2024年第1期42卷 24-31,I0006页

作者： bo-wen Li Miao xiong Mei-Hua Liu Zhi-Gao Li Long Sang Zi-Han xiong Biao Xiao Jian Pei Xiao-bo Wan Key Laboratory of Optoelectronic Chemical Materials and Devices Ministry of EducationSchoolofOptoelectronic Materials&TechnologyJianghan UniversityWuhan430056China Bejing National Laboratoryfor Molecular Sciences the Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Developing new polymeric semiconductors with excellent device performance is essential for organic electronics. herein, we synthesized two new thiazoloisoindigo(Tz II)-based polymers, namely, P(Tz II-d Th-d Th) and P(Tz II-d Th-d Tz), by copolymerizing thiophene-flanked Tz II with bithiophene and bithiazole, respectively. Owing to the more electron-deficient nature of bithiazole than bithiophene, P(Tz II-d Th-d Tz)possesses deeper LUMO/HOMO levels of-3.45/-5.47 e V than P(Tz II-d Th-d Th)(-3.34/-5.32 e V). The organic field-effect transistor(OFET) devices based on P(Tz II-d Th-d Th) exhibited p-type behaviors with an average hole mobility value as high as 1.43 cm^(2)·V^(-1)·s^(-1), while P(Tz II-d Th-d Tz)showed typical ambipolar characteristics with average hole and electron mobilities of 0.38 and 0.56 cm^(2)·V^(-1)·s^(-1). In addition, we compared the performances of both polymers with other Tz II-based polymers reported in our previous work, and showed that the charge carrier polarity can be manipulated by adjusting the number of the thiophene units between the acceptor unit. As the increase of the number of thiophene rings,charge carrier polarity shifts from electron-dominated ambipolar transport to hole-dominated ambipolar transport and then to unipolar hole transport in OFETs, which provides an effective molecular design strategy for further optimization of polymer OFET performance.

关键词： Field-effect transistor Charge carrier polarity Thiazoloisoindigo

A new interacting capillary bundle model on the multiphase flow in micropores of tight rocks

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Petroleum Science 2024年第2期21卷 1099-1112页

作者： wen-Quan Deng Tian-bo Liang wen-zhong Wang Hao Liu Jun-Lin Wu Fu-Jian Zhou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Surfactants are widely used in the fracturing fluid to enhance the imbibition and thus the oil recovery rate. However, current numerical models cannot capture the physics behind capillary imbibition during the wettability alteration by surfactants. Although the interacting capillary bundle(ICB) model shows potential in characterizing imbibition rates in different pores during wettability alteration, the existing ICB models neglect the influence of wettability and viscosity ratio on the imbibition behavior, making it difficult to accurately describe the oil-water imbibition behavior within the porous media. In this work,a new ICB mathematical model is established by introducing pressure balance without assuming the position of the leading front to comprehensively describe the imbibition behavior in a porous medium under different conditions, including gas-liquid spontaneous imbibition and oil-water *** the pore size distribution of a tight rock is known, this new model can predict the changes of water saturation during the displacement process in the tight rock, and also determine the imbibition rate in pores of different sizes. The water saturation profiles obtained from the new model are validated against the waterflooding simulation results from the CMG, while the imbibition rates calculated by the model are validated against the experimental observations of gas-liquid spontaneous imbibition. The good match above indicates the newly proposed model can show the water saturation profile at a macroscopic scale while capture the underlying physics of the multiphase flow in a porous medium at a microscopic scale. Simulation results obtained from this model indicate that both wettability and viscosity ratio can affect the sequence of fluid imbibition into pores of different sizes during the multiphase flow, where less-viscous wetting fluid is preferentially imbibed into larger pores while more-viscous wetting fluid tends to be imbibed into smaller pores. Fur

关键词： Imbibition Multiphase flow Tight rock Interacting capillary bundle model Wettability

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG wen-bo ZHOU Li ding Shi-feng WANG Ai-ming CAI Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-Lu Zhang wen-bo he Xiu-Qin Hu Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

Catalysis by subsurface metal atoms in Al(001) through electron transfer

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National Science Review 2024年第4期11卷 12-13页

作者： bo Sun ding Ma Beijing National Laboratory for Molecular Science New Cornerstone Science Laboratory College of Chemistry and Molecular Engineering Peking University

heterogeneous catalysis plays a crucial role in the chemical industry, which has evolved from the investigation of chemisorption to an electronic structure[1]. Diverse strategies, such as alloying,doping, and confining, have been applied to enhance the catalytic properties of active sites through electronic modulation. The electron transfer between active sites and substrates profoundly influences catalytic activity [2].

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