Article
Spectroscopy
Murat Kazanci, Selcuk Kaan Haciosmanoglu, Gihan Kamel
Summary: Collagen nanofibers are popular materials in regenerative medicine, and in-situ crosslinking during electrospinning process using chemical agents like genipin and glutaraldehyde is suggested for improving their properties. sFTIRM is a powerful tool for analyzing the molecular structure of collagen nanofibers. Among different crosslinkers, in-situ genipin crosslinking process performs better in preserving the native structure of electrospun collagen nanofibers.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Multidisciplinary
Maria Lago-Silva, Maria Magdalena Cid, Emilio Quinoa, Felix Freire
Summary: This article presents a new mechanism for helix inversion in polymers, which is achieved by activating/deactivating supramolecular interactions. The screw sense of the polymer is fixed by the spatial orientation of the substituents, but can be reversed through supramolecular interactions and external stimuli.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Nayana Edavan Chathoth, Aparna G. Nair, Padmesh Anjukandi
Summary: Proteins can experience uneven tensions caused by the thermal motion of the solvent. Biomolecules, especially proteins, are subjected to mechanical tensions generated by various factors. In this study, metadynamics simulations were used to investigate the folding-unfolding of the TrpZip2 beta-hairpin under external forces. The simulations revealed that the folding-unfolding process exhibits a zipper mechanism and the presence of intermediate states due to uneven forces.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Sayantan Mondal, Saumyak Mukherjee, Subhajit Acharya, Biman Bagchi
Summary: The study investigates the dissociation of an insulin dimer using a multidimensional free energy landscape, revealing the microscopic and mechanistic aspects of the process. It uncovers the initial stages and subsequent steps of the dissociation, as well as the role of hydrophobic disengagement in the process.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Polymer Science
Leonid I. Klushin, Anna S. Ivanova, Alexey A. Polotsky, Alexander M. Skvortsov
Summary: We investigated the compression and interpenetration properties of two opposing monodisperse polymer brushes under external load using analytical theory and numerical self-consistent field (SCF) approach. We proposed analytical expressions for the brush density profiles and verified them using numerical SCF calculations. Interpenetration of the brushes was quantified using the penetration length, overlap integral Gamma, and the number of brush monomer units in the foreign half-space sigma. The interpenetration parameters were studied as functions of brush separation and external pressure. A theoretical description for the solvent-mediated friction force was also proposed in the low shearing rate regime. The total friction force, including direct brush-brush friction, was found to be expressed in terms of Gamma and sigma. Our SCF data showed that the interpenetration parameters and the total sliding friction force collapsed onto universal master curves when rescaled by (N/sigma)(1/3), where N is the chain length and sigma is the surface grafting density. The kinetic friction coefficient was defined as a function of external pressure, and its universal rescaled behavior was analyzed for the limits of non-draining and free-draining brushes.
Article
Engineering, Environmental
Gyucheol Choi, Hyungmin Choi, Jihun Park, Changsoo Lee
Summary: Maintaining the proper thickness and structure of dynamic membrane (DM) is crucial for efficient filtration and biomass retention in DM bioreactors. This study investigated the effects of negative and positive applied voltages on the development and characteristics of anaerobic DM under high suspended solids conditions. The results showed that negative voltage delayed DM fouling, while positive voltage accelerated DM growth. However, excessively large voltages caused chemical fouling. Applying appropriate external voltage can effectively control DM development.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Agricultural Engineering
Jiahao Xu, Hongliang Xu, Hongguang Zhao, Hui Liu, Ling Xu, Zongsuo Liang
Summary: In this study, genome-wide analysis of the bHLH gene family in Andrographis paniculata was performed. A total of 122 genes were identified and classified into 26 subfamilies. The study showed that these genes play important roles in plant development and abiotic stress responses and can be considered as candidate regulatory factors for further research.
INDUSTRIAL CROPS AND PRODUCTS
(2022)
Article
Chemistry, Multidisciplinary
Spencer D. Golze, Stefania Porcu, Chen Zhu, Eli Sutter, Pier Carlo Ricci, Edward C. Kinzel, Robert A. Hughes, Svetlana Neretina
Summary: The study introduces a light-driven solution-based synthesis approach to produce helical gold spirals from substrate-bound seeds. This growth mode relies on three separate symmetry-breaking events: seeds with planar defects, a capping agent that impedes early growth, and Coulombic repulsion when charged growth fronts collide.
Article
Chemistry, Physical
Joachim Seelig, Anna Seelig
Summary: Protein stability is crucial in life sciences. Spectroscopic techniques are used to investigate thermal protein unfolding, and models are needed to extract thermodynamic properties. Differential scanning calorimetry (DSC) is a unique method that directly measures the heat capacity Cp(T), and a new model allows for the evaluation of thermodynamic parameters. The experimental thermodynamic data can be compared with different models.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Physical
Joachim Seelig, Anna Seelig
Summary: Protein stability is crucial in life sciences, and thermal protein unfolding is extensively studied using spectroscopic techniques. Differential scanning calorimetry (DSC) measures the thermodynamic property of heat capacity directly and provides valuable insights. However, the commonly used chemical equilibrium two-state model may lead to incorrect thermodynamic consequences. In this study, we propose two new models, the OU(T)-weighted chemical equilibrium model and the statistical-mechanical two-state model, which accurately analyze experimental heat capacity data and predict temperature profiles for protein unfolding enthalpy, entropy, and free energy.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Engineering, Manufacturing
Chigbogu Ozoegwu, Peter Eberhard
Summary: In this work, a method is developed for manufacturing cylindrical milling tools with various free-form variations of helix angle. The method simplifies the realization of arbitrary helix profiles on milling tools and significantly reduces cutting forces.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE
(2022)
Article
Thermodynamics
Mimi Duan, Lingyan Li, Xiaojun Liu, Jiajia Pei, Huihui Song
Summary: This study systematically analyzed the driving-inducing mechanisms of household residential energy transition from both external scenarios and internal psychological aspects. Through meta-analysis and meta-regression analysis, the psychological and behavioral differences in the process of household energy transition were comprehensively analyzed, revealing the evolution pattern of household residents from transition awareness to behavior. The results showed that the optimal drivers and inducers of household energy transition vary according to the diversity of clean energy types, and policy utility dislocation is the key external inducer that influences the transition from awareness to behavior of household residents.
Article
Chemistry, Multidisciplinary
Roelof Steeno, Andrea Minoia, Roberto Lazzaroni, Kunal S. Mali, Steven De Feyter
Summary: Nanoscopic lateral confinement on a graphite surface allows for the study of embryonic stages of molecular self-assembly on solid surfaces using scanning tunneling microscopy at the solution/solid interface.
CHEMICAL COMMUNICATIONS
(2022)
Article
Plant Sciences
Quangang Liu, Jiaxing Wen, Shipeng Wang, Jianhua Chen, Yongqiang Sun, Qingbai Liu, Xi Li, Shengjun Dong
Summary: This study conducted a systematic analysis of the bHLH gene family in Prunus sibirica and identified 104 PsbHLHs, which were classified and distributed unevenly on eight chromosomes. The study found that these genes share structural and functional similarities and play important roles in stress responses. Transient transfection experiments demonstrated that overexpression of the PsbHLH42 gene can improve plant cold tolerance.
FRONTIERS IN PLANT SCIENCE
(2023)
Article
Engineering, Marine
Fabrizio Greco, Paolo Lonetti
Summary: Vulnerability analyses of coastal or inland bridges in terms of flood actions and structural and fluid flow characteristics were conducted. The results showed that existing formulas cannot accurately predict the maximum design effects, and the dynamic amplification factors vary significantly in different directions. In addition, the study found that the performance of the protection fairing system is able to efficiently reduce the effects of wave load on the structure, with 40% more accuracy than the unprotected configuration.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)