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pH-controlled release feature of chitosan assembled silica nanoparticles containing nano-formulated curcumin over in vitro gastric and physiological condition

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Food Bioscience 2023年第3期53卷 2835-2846页

作者： Ozi Adi Saputra Wahyu Nur Safitriono Dyah Ellyawati Kusumaningtyas Maharani Amalia Febiana Fajar Rakhman Wibowo Sustainable Chemical Science and Technology Taiwan International Graduate Program Academia SinicaTaipei11529Taiwan Institute of Chemistry Academia SinicaTaipei11529Taiwan Department of Chemical Engineering Collage of Engineering National Taiwan UniversityTaipei10617Taiwan Master Program of Chemistry Universitas Sebelas MaretSurakarta57126Indonesia Department of Chemistry Faculty of Mathematic and Natural ScienceUniversitas Sebelas MaretSurakarta57126Indonesia

Low water solubility leading to poor bioavailability has an impact on the decreasing of curcumin uptake in the body,resulting in a deficiency of its medicinal *** study aims to overcome the limitations of curcumin by formulating a nano-emulsion called curcumin emulsion(CE).Furthermore,in order to improve the physi-cochemical properties and drug release features,the CE was encapsulated within chitosan-assembled mesoporous silica nanoparticles(Chi@SiO_(2)@CE).This material was prepared using a one-pot method and was characterized by Attenuated-total reflectance(ATR-FTIR),Particle Size Analyzer(PSA),Thermogravimetric analysis(TGA),N_(2)adsorption-desorption,Scanning Electron Microscopy(SEM),and Transmission Electron Microscopy(TEM).Additionally,antioxidant activity and in vitro drug release were also *** study demonstrated that CE has strong antioxidant activity(IC_(50)=14.14μM)compared to curcumin ***,the Chi@SiO_(2)@CE exhibited pH-controlled release behavior,with less than 20%release of curcumin under an artificial gastric environment and 50%release under pH 7.4 conditions within 24 ***,this research suggest that Chi@SiO_(2)@CE material has potential as a pH-responsive drug delivery material.

关键词： Antioxidant Biomaterials Drug delivery Mesoporous materials Nanoparticles

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General framework for the mechanical response of metallic glasses during strain-rate-dependent uniaxial compression

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Physical Review Materials 2023年第10期7卷 105604-105604页

作者： Weiwei Jin Amit Datye Udo D. Schwarz Mark D. Shattuck Corey S. O'Hern Department of Mechanical Engineering and Materials Science Yale University New Haven Connecticut 06520 USA Department of Chemical and Environmental Engineering Yale University New Haven Connecticut 06520 USA Benjamin Levich Institute and Physics Department The City College of New York New York New York 10031 USA Department of Physics Yale University New Haven Connecticut 06520 USA Department of Applied Physics Yale University New Haven Connecticut 06520 USA Graduate Program in Computational Biology and Bioinformatics Yale University New Haven Connecticut 06520 USA

Experimental data on compressive strength σmax versus strain rate ɛ̇eng for metallic glasses undergoing uniaxial compression show varying strain rate sensitivity. For some metallic glasses, σmax decreases with increasing ɛ̇eng, while for others, σmax increases with increasing ɛ̇eng, and for certain alloys σmax versus ɛ̇eng is nonmonotonic. To understand their strain rate sensitivity, we conduct molecular dynamics simulations of metallic glasses undergoing uniaxial compression at finite strain rates and coupled to heat baths with a range of temperatures T0 and damping parameters b. In the T0→0 and b→0 limits, we find that the compressive strength σmax versus temperature T obeys a “chevron-shaped” scaling relation. In the low-strain-rate regime, σmax decreases linearly with increasing T, whereas σmax grows as a power law with decreasing T in the high-strain-rate regime. For T0>0, σmax(T) deviates from the scaling curve at low strain rates, but σmax(T) rejoins the scaling curve as the strain rate increases. Enhanced dissipation reduces compression-induced heating, which causes σmax(T) to deviate from the b→0 scaling behavior for intermediate strain rates, but σmax(T) converges to the high-strain-rate power-law scaling behavior at sufficiently high strain rates. Determining σmax(T) as a function of b and T0 provides a general framework for explaining the strain rate sensitivity of metallic glasses under compression.

关键词： Compressive strength Mechanical deformation Amorphous materials Metallic glasses Molecular dynamics

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Use of corncob and pineapple peel as associated substrates for biosurfactant production

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Environmental science and Pollution Research 2024年第47期31卷 57973-57988页

作者： Santos, Brenda Lohanny Passos Vieira, Isabela Maria Monteiro Santos, Pablo Omar Lubarino Menezes, Millena Souza de Souza, Roberto Rodrigues Ruzene, Denise Santos Silva, Daniel Pereira Northeastern Biotechnology Network Federal University of Sergipe SE São Cristóvão49100-000 Brazil Center for Exact Sciences and Technology Federal University of Sergipe SE São Cristóvão49100-000 Brazil Graduate Program in Biotechnology Federal University of Sergipe SE São Cristóvão49100-000 Brazil Graduate Program in Intellectual Property Science Federal University of Sergipe SE São Cristóvão49100-000 Brazil CISAS – Center for Research and Development in Agrifood Systems and Sustainability Instituto Politécnico de Viana Do Castelo Viana Do Castelo4900-347 Portugal Department of Production Engineering Federal University of Sergipe Rodovia Marechal Rondon S/N Jardim Rosa Elze Sergipe São Cristóvão49100-000 Brazil

Biosurfactants are amphiphilic biomolecules with promising tensoative and emulsifying properties that find application in the most varied industrial sectors: environment, food, agriculture, petroleum, cosmetics, and hygiene. In the current work, a 23 full-factorial design was performed to evaluate the effect and interactions of pineapple peel and corncob as substrates for biosurfactant production by Bacillus subtilis LMA-ICF-PC 001. In a previous stage, an alkaline pretreatment was applied to corncob samples to extract the xylose-rich hydrolysate. The results indicated that pineapple peel extract and xylose-rich hydrolysate acted as partial glucose substitutes, minimizing production costs with exogenous substrates. Biosurfactant I (obtained at 8.11% pineapple peel extract, 8.11% xylose-rich hydrolysate from corncob, and 2.8109 g/L glucose) exhibited a significant surface tension reduction (52.37%) and a promising bioremediation potential (87.36%). On the other hand, biosurfactant III (obtained at 8.11% pineapple peel extract, 31.89% xylose-rich hydrolysate from corncob, and 2.8109 g/L glucose) exhibited the maximum emulsification index in engine oil (69.60%), the lowest critical micellar concentration (68 mg/L), and the highest biosurfactant production (5.59 g/L). These findings demonstrated that using pineapple peel extract and xylose-rich hydrolysate from corncob effectively supports biosurfactant synthesis by B. subtilis, reinforcing how agro-industrial wastes can substitute traditional carbon sources, contributing to cost reduction and environmental sustainability. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.

关键词： Ananas comosus Bacillus subtilis Zea mays Agro-industrial waste Bioremediation potential Emulsification index Surface tension

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The effect of stereochemical constraints on the radius of gyration of folded proteins

arXiv

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arXiv 2025年

作者： Logan, Jack A. Sumner, Jacob Grigas, Alex T. Shattuck, Mark D. O'Hern, Corey S. Department of Mechanical Engineering Yale University New HavenCT06520 United States Graduate Program in Computational Biology & Biomedical Informatics Yale University New HavenCT06520 United States Integrated Graduate Program in Physical and Engineering Biology Yale University New HavenCT06520 United States Benjamin Levich Institute and Physics Department The City College of New York New YorkNY10031 United States Department of Applied Physics Yale University New HavenCT06520 United States Department of Physics Yale University New HavenCT06520 United States

Proteins are composed of linear chains of amino acids that fold into complex three-dimensional structures. A general feature of folded proteins is that they are compact with a radius of gyration Rg(N) ∼ Nν that obeys power-law scaling with the number of amino acids N in each protein and ν ∼ 1/3. In this study, we investigate the internal scaling of the radius of gyration Rg(n) versus the chemical separation n between amino acids for all subchains of length n. We show that for globular proteins Rg(n) ∼ nν1,2 with a larger exponent ν1 > 1/3 for small n and a smaller exponent ν2 g(N) ∝ Nν. To describe this scaling behavior for Rg(n), we carry out folding simulations for a series of coarse-grained models for proteins beginning with the freely-jointed and freely-rotating chain models composed of spherical monomers and varying degrees of stereochemical constraints. We show that a minimal model, which coarse-grains amino acids into a single spherical backbone atom and one variable-sized spherical side-chain atom, and enforces bend- and dihedral-angle constraints, can recapitulate Rg(n) for x-ray crystal structures of globular proteins. In addition, this model predicts the correct average packing fraction and size of the hydrophobic core, which are two key physical features that can be used to distinguish between computational 'decoys' and correctly folded proteins in protein design applications. © 2025, CC BY.

关键词： Spheres

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Local and global measures of the shear moduli of jammed disk packings

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Physical Review E 2023年第5期107卷 054903-054903页

作者： Shiyun Zhang Weiwei Jin Dong Wang Ding Xu Jerry Zhang Mark D. Shattuck Corey S. O'Hern Department of Physics University of Science and Technology of China Hefei Anhui 230026 China Department of Mechanical Engineering and Materials Science Yale University New Haven Connecticut 06520 USA Benjamin Levich Institute and Physics Department The City College of New York New York New York 10031 USA Department of Physics Yale University New Haven Connecticut 06520 USA Department of Applied Physics Yale University New Haven Connecticut 06520 USA Graduate Program in Computational Biology and Bioinformatics Yale University New Haven Connecticut 06520 USA

Strain-controlled isotropic compression gives rise to jammed packings of repulsive, frictionless disks with either positive or negative global shear moduli. We carry out computational studies to understand the contributions of the negative shear moduli to the mechanical response of jammed disk packings. We first decompose the ensemble-averaged, global shear modulus as 〈G〉=(1−F−)〈G+〉+F−〈G−〉, where F− is the fraction of jammed packings with negative shear moduli and 〈G+〉 and 〈G−〉 are the average values from packings with positive and negative moduli, respectively. We show that 〈G+〉 and 〈|G−|〉 obey different power-law scaling relations above and below pN2∼1. For pN2>1, both 〈G+〉N and 〈|G−|〉N∼(pN2)β, where β∼0.5 for repulsive linear spring interactions. Despite this, 〈G〉N∼(pN2)β′ with β′≳0.5 due to the contributions from packings with negative shear moduli. We show further that the probability distribution of global shear moduli P(G) collapses at fixed pN2 and different values of p and N. We calculate analytically that P(G) is a Γ distribution in the pN2≪1 limit. As pN2 increases, the skewness of P(G) decreases and P(G) becomes a skew-normal distribution with negative skewness in the pN2≫1 limit. We also partition jammed disk packings into subsystems using Delaunay triangulation of the disk centers to calculate local shear moduli. We show that the local shear moduli defined from groups of adjacent triangles can be negative even when G>0. The spatial correlation function of local shear moduli C(r⃗) displays weak correlations for pnsub2<10−2, where nsub is the number of particles within each subsystem. However, C(r⃗) begins to develop long-ranged spatial correlations with fourfold angular symmetry for pnsub2≳10−2.

关键词： Jamming Packing & jamming problems Granular materials

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Gravitational-wave constraints on scalar-tensor gravity from a neutron star and black-hole binary GW200115

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Physical Review D 2024年第10期109卷 104072-104072页

作者： Hiroki Takeda Shinji Tsujikawa Atsushi Nishizawa Department of Physics Kyoto University Kyoto 606-8502 Japan Department of Physics Waseda University 3-4-1 Okubo Shinjuku Tokyo 169-8555 Japan Physics Program Graduate School of Advanced Science and Engineering Hiroshima University Higashi-Hiroshima Hiroshima 739-8526 Japan

In nonminimally coupled theories where a scalar field ϕ is coupled to the Ricci scalar, neutron stars (NSs) can have scalar charges through an interaction with matter mediated by gravity. On the other hand, the same theories do not give rise to hairy black hole (BH) solutions. The observations of gravitational waves (GWs) emitted from an inspiralling NS-BH binary system allows a possibility of constraining the NS scalar charge. Moreover, the nonminimally coupled scalar-tensor theories generate a breathing scalar mode besides two tensor polarizations. Using the GW200115 data of the coalescence of a BH-NS binary, we place observational constraints on the NS scalar charge as well as the nonminimal coupling strength for a subclass of massless Horndeski theories with a luminal GW propagation. Unlike past related works, we exploit a waveform for a mixture of tensor and scalar polarizations. Taking the breathing mode into account, the scalar charge is more tightly constrained in comparison to the analysis of the tensor GWs alone. In nonminimally coupled theories including Brans-Dicke gravity and spontaneous scalarization scenarios with/without a kinetic screening, we put new bounds on model parameters of each theory.

关键词： Alternative gravity theories Experimental studies of gravity General relativity Gravitational wave detection Gravitational wave sources Gravitational waves Binary stars Neutron stars & pulsars

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Investigating the Impact of Data Augmentation for Fine-Grained Grocery Product Classification Based on Vision Transformer

Investigating the Impact of Data Augmentation for Fine-Grain...

引用

Artificial Intelligence Robotics, Signal and Image Processing (AIRoSIP), International Conference on

作者： Rissa Rahmania Yaya Heryadi Lukas Lukas Wayan Suparta Ilvico Sonata Computer Science Department BINUS Graduate Program Computer Science Bina Nusantara University Jakarta Indonesia Cognitive Engineering Group (CEG) Faculty of Engineering Universitas Katolik Atma Jaya Jakarta Indonesia Department of Electrical Engineering Faculty of Industrial Technology Institut Teknologi Nasional Yogyakarta Yogyakarta Indonesia

ISBN: (数字)9798350327472

ISBN: (纸本)9798350327489

The existence of fine-grained image classification supporting smart retail provides effectiveness in recognizing products with high similarity. However, the generic classification method performs poorly in identifying products from a subordinate category. This paper aims to identify augmentation techniques to leverage the Vision Transformer (ViT) model to classify the fine-grained grocery product, which involves embedding patches and transformer encoders to extract the main features. First, we develop a fine-grained image dataset with ColorJitter, CutOut, and combining both augmentations. Secondly, we perform experiments and analysis of ViT size, embedded patch size and image size in the patch embedding process. Lastly, the ViT model are evaluated according to the image sizes 224, 384, and 512 in accuracy, loss, and confusion matrix. The highest accuracy was obtained at 0.9922. The ColorJitter and CutOut improved the confusion matrix in ViT-B/16 and ViT-L/16 with an image size of 384 and 512. The results show that both augmentations in the ViT model are able to distinguish fine-grained grocery products.

关键词： Surveys Computer vision Accuracy Image recognition Transformers Feature extraction Data augmentation Artificial intelligence Image classification

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A Family of Edge-Centered Finite Volume Schemes for Heterogeneous and Anisotropic Diffusion Problems on Unstructured Meshes

SSRN

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SSRN 2023年

作者： Liu, Ziqi Miao, Shuai Zhang, Zhimin Department of Mathematical Sciences Tsinghua University Beijing100084 China Graduate School of China Academy of Engineering Physics Beijing100088 China Applied and Computational Mathematics Division Beijing Computational Science Research Center Beijing100193 China Department of Mathematics Wayne State University DetroitMI48202 United States

We present a family of edge-centered finite volume schemes for steady-state diffusion problems on general unstructured polygonal meshes. These schemes are locally conservative with respect to the dual mesh and have only edge-centered unknowns with no extra auxiliary variable. A general form of edge-centered finite volume scheme based on linearity-preserving criterion is proposed, and two specific schemes (ECS-I and ECS-II) are constructed. In particular, ECS-II derives a symmetric and positive definite matrix, and its coercivity can be rigorously demonstrated. The ECS-II is unconditionally stable in any star-shaped mesh. Besides, the relationship between edge-centered schemes and the finite volume element method with Crouzeix-Raviart element and the finite difference method with X-shaped stencil is discussed. Numerical experiments indicate that edge-centered schemes have optimal convergence rate and are robust even for highly anisotropic problems and distorted meshes. © 2023, The Authors. All rights reserved.

关键词： Finite difference method

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Ag Segregation and Interfacial Characterization of the Hexagonal β(Mg2Si)-Phase in Al-Mg-Si-Ag Alloy

SSRN

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SSRN 2024年

作者： Ahmed, Abrar Uttarasak, Kanokwan Tsuchiya, Taiki Lee, Seungwon Nishimura, Katsuhiko Nunomura, Norio Watanabe, Shoma Malik, Ayesha Shimizu, Kazuyuki Hirayama, Kyosuke Toda, Hiroyuki Yamaguchi, Masatake Tsuru, Tomohito Nakamura, Junya Matsuda, Kenji Ikeno, Susumu Department of Mechanical Engineering University of Toyama Japan Graduate School of Science and Engineering for Education University of Toyama Toyama930-8555 Japan Graduate School of Science and Engineering for Research University of Toyama Toyama930-8555 Japan Department of Physics Riphah International University Islamabad Pakistan Graduate School of Science and Engineering Tottori University 4-101 koyama Minami Tottori Japan Department of Materials Science and Engineering Kyoto University Kyoto606-8501 Japan Department of Mechanical Engineering Kyushu University Fukuoka819-0395 Japan Center for Computational Science and e-Systems Japan Atomic Energy Agency Ibaraki Tokai319-1195 Japan Nuclear Science and Engineering Center Japan Atomic Energy Agency Ibaraki Tokai319-1195 Japan Material Solutions Division Kobelco Research Institute Inc. 1-5-5 Takatsukadai Nishi-ku Hyogo Kobe651-2271 Japan

This study aims to clarify the interface of the hexagonal β(Mg2Si)-phase in Al-Mg-Si-Ag alloys. The orientation relationship, interfacial conditions, misfit, and Ag segregation between the hexagonal β(Mg2Si)-phase and the Al matrix were investigated using optical microscopy (OM), focused ion beam (FIB), and scanning transmission electron microscopy (STEM). In previous research, a hexagonal tabular β(Mg2Si)-phase was identified on the {111} habit plane of the Al matrix with a new orientation relationship [{111}Al || {111}hex.β, Al || hex.β], as opposed to the conventional β(Mg2Si)-phase, which was found on the {100} habit plane [{001}Al || {001}con.β, Al || con.β]. Ag segregation was observed on the {111}Al // {111}hex.β, {122}Al // {110}hex.β, and {112}Al // {111}hex.β facets of the hexagonal β(Mg2Si)-phase and Al matrix. These observations provide valuable insights into how these differences influence the behavior of Mg2Si crystals. Understanding these factors is crucial for predicting the microstructural development of Al-Mg-Si alloys and for designing materials with tailored properties. © 2024, The Authors. All rights reserved.

关键词： Focused ion beams

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Acid-catalyzed hydrothermal treatment of sewage sludge: effects of reaction temperature and acid concentration on the production of hydrolysis by-products

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Biomass Conversion and Biorefinery 2023年第9期13卷 7533-7546页

作者： Pham, Van Toi Guan, Chung-Yu Han, Po-Chun Matsagar, Babasaheb M. Wu, Kevin C. W. Ahamad, Tansir Chang, Ching-Yuan Yu, Chang-Ping Graduate Institute of Environmental Engineering National Taiwan University Taipei106 Taiwan Faculty of Environmental Engineering National University of Civil Engineering 55 Giai Phong Hai Ba Trung Hanoi100000 Viet Nam Department of Environmental Engineering National Ilan University Yilan260 Taiwan Ph.D. Program of Green Materials and Precision Devices National Taiwan University Taipei10617 Taiwan Department of Chemical Engineering National Taiwan University No. 1 Sec. 4 Roosevelt Road Taipei10617 Taiwan Department of Chemistry College of Science King Saud University P.O. Box 2455 Riyadh11451 Saudi Arabia Water Innovation Low Carbon and Environmental Sustainability Research Center National Taiwan University Taipei106 Taiwan

Sewage sludge (SS) is an organic biomass from wastewater treatment plants, but the use of SS to produce bio-based chemicals under acid-catalyzed hydrolysis (ACH) processes is not well investigated. In this study, ACH processes were performed at 120, 150, and 180 °C using sulfuric acid (H2SO4) with concentrations of 0–0.5 M within a reaction time of 90–180 min to produce bio-based chemicals from SS. The results showed that the reaction temperature, reaction time, and concentrations of H2SO4 affected the yields of sugars, levulinic acid (LA), and 5-hydroxymethylfurfural (HMF). The highest xylose and glucose yields were 7.69 mol% and 5.22 mol% at 120 °C with 0.5 M H2SO4 during the 180 min of reaction time, respectively. Besides, under the ACH process at 180 °C and 180 min, the yield of LA reached a maximum value of 0.48 mol% at 0.5 M H2SO4, and the highest yield of HMF was 1.66 mol% at 0.1 M H2SO4. The data obtained also indicated that the ACH process led to an increase in soluble chemical oxygen demand, dissolved organic carbon, and total dissolved nitrogen. Fluorescence excitation-emission matrix of dissolved organic matter and thermogravimetric analysis of the treated SS further supported the enhanced solubilization of SS after ACH process, especially under higher reaction temperature and concentrations of H2SO4. Although the lower yields of bio-based chemicals might restrict the downstream recovery of the target products, the largely improved SS solubilization by ACH suggests that acid-catalyzed hydrothermal hydrolysis process has potential as an alternative pretreatment method of SS. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.

关键词： Sewage sludge

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