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chromatin remodeling and nucleoskeleton synergistically control osteogenic differentiation in different matrix stiffnesses

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MATERIALS TODAY BIO 2023年 20卷

作者： Xu, Xinxin Zhang, He Li, Yuzhou Liu, Fengyi Jing, Zheng Ren, Mingxing chen, Tao Fu, Yiru Wu, Yanqiu Ji, Ping Yang, Sheng Chongqing Med Univ Coll Stomatol Chongqing Peoples R China Chongqing Key Lab Oral Dis & Biomed Sci Chongqing Peoples R China Chongqing Municipal Key Lab Oral Biomed Engn Highe Chongqing Peoples R China Chongqing Med Univ Stomatol Hosp Coll Stomatol Chongqing Key Lab Oral Dis & Biomed Sci 426 Songshi North Rd Chongqing 401147 Peoples R China

Matrix stiffness plays an important role in determining cell differentiation. The expression of cell differentiation -associated genes can be regulated by chromatin remodeling-mediated DNA accessibility. However, the effect of matrix stiffness on DNA accessibility and its significance for cell differentiation have not been investigated. In this study, gelatin methacryloyl (GelMA) hydrogels with different degrees of substitution were used to simulate soft, medium, and stiff matrices, and it was found that a stiff matrix promoted osteogenic differentiation of Mc3T3-E1 cells by activating the Wnt pathway. In the soft matrix, the acetylation level of histones in cells was decreased, and chromatin condensed into a closed conformation, affecting the activation of beta-catenin target genes (Axin2, c-Myc). Histone deacetylase inhibitor (TSA) was used to decondense chromatin. However, there was no significant in-crease in the expression of beta-catenin target genes and the osteogenic protein Runx2. Further studies revealed that beta-catenin was restricted to the cytoplasm due to the downregulation of lamin A/c in the soft matrix. Over -expression of lamin A/c and concomitant treatment of cells with TSA successfully activated beta-catenin/Wnt signaling in cells in the soft matrix. The results of this innovative study revealed that matrix stiffness regulates cell osteogenic differentiation through multiple pathways, which involve complex interactions between transcription factors, epigenetic modifications of histones, and the nucleoskeleton. This trio is critical for the future design of bionic extracellular matrix biomaterials.

关键词： Matrix stiffness chromatin remodeling Lamin A c Mechanotransduction Osteogenic differentiation

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characterization of the key odorants and investigation of the effects of drying methods on the aroma, taste, color and volatile profiles of the fruit of clausena anisum-olens (Blanco) Merr.

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LWT-FOOD ScIENcE AND TEcHNOLOGY 2023年 175卷

作者： Luo, Lianfeng Wang, Jieqiong Li, Meiqin Zhang, Yingbin Wang, Yuwan Xu, Yongquan chen, Haisheng Zhu, Yan Feng, Zhihui Yin, Junfeng Guangxi South Subtrop Agr Sci Res Inst Chongzuo 532415 Peoples R China Chinese Acad Agr Sci Tea Res Inst Hangzhou 310008 Peoples R China

With a distinctive aroma, Shanhuangpi (SHP), the fruit of the plant clausena anisum-olens (Blanco) Merr., has been newly developed as a commercial fruit resource. The fresh fruit deteriorates rapidly due to its high respiration and metabolism. Therefore, an effective drying process is urgently needed for its preservation. The influence of two commonly used drying methods for plant materials, i.e., vacuum freeze-drying (VFD) and hot air drying (HAD) was evaluated on the aroma, taste, color, and volatile profiles of this fruit. The results indicated that the VFD process well retained the color and volatile composition of the fresh fruit but produced extra graininess and sticky mouthfeel. Alternatively, the HAD process offered a shorter drying time, kept a more palatable sour/sweet ratio, but created a darker brown color and shrinking texture of the fruit. The volatile components were enriched by the micro-chamber/thermal extractor (mu-cTE) and 38 compounds were identified with gas chromatography-mass spectrometry. Sixteen odor-active compounds (detection frequency >= 4) were detected by gas chromatography-olfactometry. Results obtained in this study can be served as a reference for the evaluation and further development of SHP.

关键词： c anisum-Olens Shanhuangpi (SHP) Drying process Aroma characterization Multivariate analysis

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Improvement of sensitization and intergranular corrosion of AISI type 304L stainless steel through thermo-mechanical treatment

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cORROSION ScIENcE 2023年第1期213卷

作者： Shit, Gopinath Mariappan, K. Ningshen, S. Indira Gandhi Ctr Atom Res Met & Mat Grp CSTD Kalpakkam 603102 Tamil Nadu India Homi Bhaba Natl Inst Training Sch Complex Mumbai 400094 India Indira Gandhi Ctr Atom Res Mech Met Div Met & Mat Grp Kalpakkam 603102 Tamil Nadu India

In this study, solution annealed AISI type 304 L stainless steel (SS) was thermo-mechanically processed (TMP) by introducing different cold-rolled 20 and 40 percentages, followed by annealing at 900 degrees c and water quenching. Sensitization was carried out by heat treatment for 24 h at 675 degrees c. The degree of sensitization (DOS) was measured by the electrochemical double loop potentiokinetic reactivation (DL-EPR) technique, indicating high DOS (12.5%) for the as-received specimen. The grain boundary engineering (GBE) by TMP treatment substantially lowered the DOS (7.1%) and resistance against intergranular corrosion (IGc) in a boiling nitric acid medium.

关键词： A Stainless steel B Electrochemical calculation Weight loss c Acid corrosion

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Multilayer nanocomposite films with enhanced piezoelectric properties doping PZT nanofibers

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cERAMIcS INTERNATIONAL 2023年第17期49卷 28474-28483页

作者： Yuan, chongXiao Zhang, chao Xiao, Shibing Yang, cheng Zhang, Nannan Sun, Huajun Wuhan Univ Technol State Key Lab Silicate Mat Architectures Wuhan 430070 Peoples R China Wuhan Univ Technol Sch Mat Sci & Engn Wuhan 430070 Peoples R China Wuhan Univ Technol Sch Chem Chem Engn & Life Sci Wuhan 430070 Peoples R China Adv Ceram Inst Zibo New & High Tech Ind Dev Zone Zibo 255000 Peoples R China

Flexible electronics components, including wearable sensors, miniature energy supply devices, and energy harvesting systems based on polymer piezoelectric materials, have garnered extensive attention. This study focuses on the preparation of PZT nanofibers (PZT NFs) via electrospinning and their modification with polydopamine, the fabrication of PVDF/PZT NFs nanocomposite films through casting, and the production of tri-layer nanocomposite films using hot pressing. The alignment of the PZT NFs perpendicular to the electric field direction enhances the breakdown strength (Eb) and facilitates the polarization of the nanocomposite films. At the interlayer interfaces within the tri-layer structure, electron traps extend the breakdown path, attenuating charge concentration and mitigating the electric field concentration effect. consequently, the tri-layer films exhibit excellent electrical properties. Notably, the P4P tri-layer nanocomposite films have a high Eb of 290.47 kV/mm and a piezoelectric coefficient of -24 pc/N. This paper presents a promising strategy for enhancing the piezoelectric properties of polymer piezoelectric materials applied in sensors and energy harvesting systems.

关键词： A Tape casting B composites c Piezoelectric properties D PZT

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A wideband accurate compact 6-bit phase shifter in 0.15-μm GaAs technology

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MIcROWAVE AND OPTIcAL TEcHNOLOGY LETTERS 2023年第2期65卷 534-540页

作者： Zeng, Jialong Xie, chunshuang Zhang, Desheng Feng, Jie Tan, cheng Yu, Zhongjun Chinese Acad Sci Aerosp Informat Res Inst Beijing Peoples R China Univ Chinese Acad Sci Sch Elect Elect & Commun Engn Beijing Peoples R China

A Ku wideband accurate compact 6-bit digital phase shifter is designed in this letter using three different switched phase shift structures: the switched L/c structure, T-type structure, and high-pass/low-pass network. To improve the bandwidth and the gain flatness, an improved switched L/c structure is used and the systematic cascade sequence of the phase shifter is optimized. The improved switched L/c structure solves the problem that conventional L/c networks are hypersensitive to the coupling capacitance at high-frequency input. As a result, the improved L/c structure can achieve wideband and better s-parameters. The proposed 6-bit switched phase shifter is implemented in 0.15-mu m GaAs pHEMT process. The measured root-mean-square (rms) phase error is less than 2.8 degrees at 12-18 GHz, and the average insertion loss (IL) is 6.5-6.9 dB. The chip size of the proposed 6-bit digital phase shifter is 3.1 x 1 mm(2), including all RF and dc pads, which is very suitable for radar systems.

关键词： digital phase shifter high-pass low-pass network root-mean-square (rms) switched L c T-type structure

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Electron energy loss spectra of ZnSe using linear response theory

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SOLID STATE cOMMUNIcATIONS 2023年第1期371卷

作者： Joshi, Nikhil Maurya, Vijay Joshi, K. B. ML Sukhadia Univ Dept Phys Udaipur 313001 India

Beginning from the density functional theory, the linear response theory within the framework of time dependent density functional theory has been applied to study the electron energy loss spectra of ZnSe. The ground state is obtained using first-principles Full-Potential Linearized Augmented Plane Wave method. After settling the crystal structure, the electronic properties such as band structure and density of states are calculated. The electron energy loss spectra are found considering exchange-correlation kernels namely adiabatic local density approx-imation, long range contribution and the bootstrap. For the sake of completeness and comparison, results using random phase approximation are also incorporated. The inclusion of local field effects in all the kernels improve the agreement of optical and electron energy loss spectra with experimental data. Moreover, agreement in the plasmon peak positions, found using different kernels considering local field effects, with experimental data has also improved.

关键词： A Semiconductor c EELS D TD-DFT Optical properties

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catalytic degradation of bisphenol A by heterogeneous bimetal composite carbon in the PMS and H2O2 systems: Performance and mechanism

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JOURNAL OF cLEANER PRODUcTION 2023年第1期414卷

作者： He, Xin Yang, Xin Zhang, chaoyang Xiao, Yuan Tang, Yulin Tongji Univ Coll Environm Sci & Engn Shanghai 200092 Peoples R China Minist Water Resources Key Lab Water Supply Water Saving & Water Environm Shanghai 200092 Peoples R China Tongji Univ 1239 Siping Rd Shanghai 200092 Peoples R China

Bisphenol A (BPA) has caused adverse effects on human health and natural environment as a poisonous endocrine disrupting chemical. In this study, the bimetal composite carbon material (co & Ni/c) with carbon nanotubes was fabricated for BPA degradation by the catalytic pyrolysis method. The dense carbon nanotubes were observed on the carbon surface with a specific surface area of up to 265.68 m2/g. The cobalt oxide and nickel oxide were distributed evenly causing more catalytic sites. The factors affecting catalytic efficiency for degrading BPA by the peroxymonosulfate (PMS) and hydrogen peroxide (H2O2) systems were investigated and compared systematically. The co & Ni/c showed better catalytic performance with a BPA degradation rate of nearly 80%- 100% in the co & Ni/c-PMS process. However, BPA was difficult to be removed completely by H2O2 with a mineralization efficiency below 40% under most reaction conditions. The different degradation pathways and mechanisms under the oxidation of SO4 & BULL;¡ and HO & BULL;were also discussed respectively, and the intermediate reactions included radical adduct formation, hydroxylation, skeleton oxidation rearrangement, dehydration and ring cleavage. It was proved that the stable co & Ni/c possessed good reusability for remaining 77% removal rate of BPA after a 4-stage adsorption-degradation reaction. This paper revealed that the synthetic co & Ni/c was hopeful as the adsorption material with efficient catalytic activity to provide new insight into BPA in-situ degradation.

关键词： Bisphenol A co & amp Ni c Peroxymonosulfate Hydrogen peroxide catalytic degradation

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Predicting the parabolic growth rate constant for high-temperature oxidation of steels machine models

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cORROSION ScIENcE 2023年第1期221卷

作者： Aghaeian, S. Nourouzi, F. Sloof, W. G. Mol, J. M. c. Boettger, A. J. Delft Univ Technol Fac Mech Maritime & Mat Dept Mat Sci & Engn Mekelweg 2 NL-2628 CD Delft Netherlands Delft Univ Technol Fac Elect Engn Math & Comp Sci Dept Elect Sustainable Energy Mekelweg 4 NL-2628 CD Delft Netherlands

The parabolic growth rate constant (kp) of high-temperature oxidation of steels is predicted via a data analytics approach. Four machine learning models including Artificial Neural Networks, Random Forest, k- Nearest Neighbors, and Support Vector Regression are trained to establish the relations between the input features (composition and temperature) and the target value (kp). The models are evaluated by the indices: Mean Absolute Error, Mean Squared Error, Root Mean Squared Error and coefficient of Determination. The steel composition regarding cr and Ni content and the temperature were the most significant input features controlling the oxidation kinetics.

关键词： A Steel B Modeling studies c Oxidation High-temperature corrosion Kinetic parameters

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Microstructure and fracture behaviours of Nb-16Si ultra-high temperature alloy fabricated by laser directed energy deposition

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INTERMETALLIcS 2023年第1期157卷

作者： Liao, Junhua Wei, Zhenhe Yu, Fan Yu, Youxing Peng, Hui Sha, Jiangbo Beijing Univ Aeronaut & Astronaut Sch Mat Sci & Engn Key Lab Aerosp Mat & Performance Minist Educ Beijing 100191 Peoples R China

We prepared Nb-16Si ingot via the laser directed energy deposition (L-DED) using mixed pure Nb and Nb5Si3 alloy powders, and investigated the microstructure and fracture behaviour of the L-DEDed samples along di-rections that were parallel and perpendicular to the built direction, as well as the fracture behavior of the arc melting Nb-16Si sample for comparison. The L-DED molten pool approximately showed a scaly-like morphology, and the fine microstructure containing primary dendritic NbSS arm and eutectic colony of NbSS + Nb3Si was obtained, which oriented to the built direction and the scanning direction. The multiformity of orientation re-lationships (ORs) with the small Miller indices in the NbSS/Nb3Si couple was confirmed, while the ORs, such as (0 1 1) NbSS//(0 2 0) Nb3Si, [0 1 1] NbSS//[0 0 1] Nb3Si, and (1 1 0) NbSS//(2 0 0) Nb3Si, [1 1 2] NbSS//[0 0 1] Nb3Si were the dominant. The fine Nb phase in the L-DEDed sample fractured in a mixed dimple, tear and cleavage mode, resulting in higher fracture toughness KQ of approximately 7.6-8.6 MPa m1/2. As for the arc -melting Nb-16Si sample with coarsened microstructure, the NbSS phase usually failed in a single cleavage mode, leading to a low KQ value of 6.8 MPa m1/2.

关键词： A intermetallics B fracture toughness c laser processing and cladding D Microstructure G aero-engine components

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Influence of citric Acid and Hydrochloric Acid with High-Pressure Processing on characteristics of Pectic Polysaccharide from choerospondias axillaris Fruit Peel

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FOOD AND BIOPROcESS TEcHNOLOGY 2023年第6期16卷 1235-1245页

作者： Li, Lu chen, Shupeng Lu, Jinghui Bu, Zhibin Yu, Yuanshan Wu, Jijun Yang, Wanyuan Xu, Yujuan Peng, Jian Guangdong Acad Agr Sci Sericultural & Argi Food Res Inst Minist Agr & Rural Affairs Guangdong Key Lab Agr Prod ProcKey Lab Funct Food 133 Yiheng StDongguanzhuang Rd Guangzhou 510610 Peoples R China Guangdong Jiabao Grp Co Ltd Chaozhou 515638 Guangdong Peoples R China

The aim of this study was to investigate the influence of citric acid combined with high-pressure processing (HPP) on the characteristics of pectic polysaccharide of choerospondias axillaris fruit peel (cPP). Therefore, the physicochemical, structural, and emulsifying properties of cPP extracted by hydrochloric acid (HEP), HPP-assisted hydrochloric acid (HEP + HPP), citric acid (cEP), and HPP-assisted citric acid (cEP + HPP) were analyzed. Results showed that citric acid and HPP had a synergetic impact on extraction yield, weight-average molecular weight (Mw), emulsion ability (EA), and apparent viscosity of cPP;hence, the highest extraction yield (48.49%) and EA (70.25%) coupled with the lowest Mw (263.80 kDa) and apparent viscosity were observed in cEP + HPP. However, the effects of citric acid and HPP on DA, DM, and GalA of cPP were opposite. The lowest DA and DM were found in HEP + HPP. Moreover, both citric acid and HPP had great influences on the structure of cPP. The cPP extracted by citric acid had a lower crystallinity, and the microstructure of cPP extracted with HPP assistance was rougher. In summary, HPP-assisted citric acid extraction could improve the extraction yield and emulsion property of cPP.

关键词： c axillaris fruit peel Pectic polysaccharide Extraction method Physicochemical characteristics Structural properties Emulsifying quality

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