Article
Materials Science, Multidisciplinary
V. M. Litvyak, R. Cherbunin, V. K. Kalevich, A. Lihachev, A. Nashchekin, M. Vladimirova, K. Kavokin
Summary: The efficiency of adiabatic demagnetization of the nuclear spin system in a solid is limited by quadrupole effects. However, recent experiments in GaAs validate the thermodynamic description of the NSS despite a significant quadrupole interaction. This suggests that nuclear spin temperature can be used as a probe of nuclear magnetic resonances.
Article
Chemistry, Physical
L. K. R. Duarte, A. V. N. C. Teixeira, L. G. Rizzi
Summary: A computational methodology is proposed to obtain the viscoelastic response of dilute solutions of semiflexible filaments, by evaluating the dynamical properties through the fluctuation-dissipation theorem, microrheological approach, and relaxation simulations. The effects of bending energy on viscoelasticity were assessed, and the methodology was validated by comparing numerical results with experimental data on DNA and collagen solutions.
Article
Chemistry, Multidisciplinary
Martin Glaser, Paul Mollenkopf, Dusan Prascevic, Catarina Ferraz, Josef A. Kaes, Joerg Schnauss, David M. Smith
Summary: To understand the mechanical behaviors of complex biomaterials, it is important to connect the nanoscale properties of their constituent components with those of the bulk material. Crosslinked networks of semiflexible polymers play a crucial role in biological systems and synthetic materials. By using a synthetic model system based on DNA self-assembly, the impact of binding affinity on mechanical response was explored. The study demonstrated the potential for gaining deeper understanding of both biological and engineered hydrogel systems.
Article
Physics, Multidisciplinary
Marcus V. Alves Ribeiro, Aurel Jurjiu, Mircea Galiceanu
Summary: The relaxation dynamics of a new type of hyperbranched polymer networks constructed using a degree distribution specific to scale-free networks are studied. The topology of the networks is controlled by three parameters: gamma, K-min, and K-max. The influence of these parameters and the stiffness parameter q on the relaxation quantities is investigated. Various scaling behaviors are observed in the dynamical quantities for different combinations of the parameters.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2022)
Review
Polymer Science
Denis A. Markelov, Anna S. Semisalova, Mikhail A. Mazo
Summary: Dendrimers are tree-like symmetric macromolecules with unique properties, attracting researchers' interest. Differences in structure and conformation can be influenced by solvent selectivity and compatibility of terminal and core groups, leading to the formation of regions with lower polymer density inside the dendrimer.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2021)
Article
Polymer Science
Manisha Handa, Parbati Biswas
Summary: This study investigates the relaxation dynamics of ring polymers in dilute solutions with both repulsive excluded volume interactions and attractive interactions using Rouse-Zimm theory. The results show that the overall motion dominates the relaxation of ring polymers with repulsive interactions, while the opposite is true for ring polymers with attractive interactions. The spin-lattice relaxation rate exhibits a characteristic maximum at different frequencies.
Article
Chemistry, Physical
Clemens Kauffmann, Anna Zawadzka-Kazimierczuk, Georg Kontaxis, Robert Konrat
Summary: The study demonstrates that using a modern MaxEnt reweighting approach to interpret CCR rates of Ubiquitin can resolve CCR-encoded structural information despite uncertainties. A suitable balance between complementary CCR experiments and prior information is crucial in mapping backbone dihedral angle distributions. Using Ubiquitin as an example, the CCR rates are capable of characterizing both rigid and flexible residues, indicating their potential in studying disordered proteins.
Article
Chemistry, Multidisciplinary
Weicheng Cao, Zhenfeng Pang, Xiaoqi Zhou, Zhenming Cao, Jiachen Li, Qi Wang, Xiaogang Peng, Xueqian Kong
Summary: The interaction between ligands is crucial for the surface chemistry, solution properties, and self-assembly processes of colloidal nanocrystals. However, studying ligand-ligand interaction is challenging due to the disordered and dynamic nature of the surface, the low electron contrast of organic moieties, and the non-characteristic weak intermolecular forces. In this study, the authors developed an advanced solid-state nuclear magnetic resonance (SSNMR) measurement and modeling strategy to quantify the dynamic volume of chain segments, which is inversely proportional to the intermolecular interaction energy. The calculated ligand-ligand interaction energy was found to determine the solution dispersity and melting transitions of the nanocrystals. This concept of dynamic volume can be extended to predict the interaction energies of alkanoate ligands.
CELL REPORTS PHYSICAL SCIENCE
(2023)
Article
Polymer Science
Jessie Wong, Violeta Toader, Linda Reven
Summary: This study demonstrates that lyotropic liquid crystalline (LC) nanomaterials can be achieved from spherical nanoparticles (NPs) with semi-flexible polymer ligands. The high degree of orientation order of the magnetized materials indicates that the splaying of the ligand shell transforms the spherical NPs into rod-like shapes, which then assemble to produce lyotropic LC phases and linear NP arrays.
MACROMOLECULAR RAPID COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Cristina Di Carluccio, Rosa Ester Forgione, Marco Montefiori, Monica Civera, Sara Sattin, Giovanni Smaldone, K. Fukase, Y. Manabe, Paul R. Crocker, Antonio Molinaro, Roberta Marchetti, Alba Silipo
Summary: Siglecs are a group of cell-surface receptors belonging to the I-type lectin family, mostly expressed on innate immune cells, among which CD22 plays a key role in maintaining tolerance and preventing autoimmune responses. This study focused on the interaction of CD22 with sialoglycans, specifically exploring the role of N-glycolyl neuraminic acid (Neu5Gc) in this process. Findings suggested a comparable molecular recognition profile between human and murine forms of CD22, providing insights for innovative diagnostic and therapeutic methodologies in immune response modulation.
Article
Construction & Building Technology
Jing Li, Sarah Mailhiot, Anu M. Kantola, He Niu, Harisankar Sreenivasan, Ville-Veikko Telkki, Paivo Kinnunen
Summary: Characterizing and understanding the mechanisms underlying geopolymerization are crucial for the widespread commercial production of sustainable construction material. This study used non-destructive H-1 NMR relaxometry to monitor the curing process of metakaolin-based geopolymers. The results showed that the silica-to-alumina ratio (Si/Al) affects the reaction stages of geopolymerization.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Polymer Science
Koudai Takamatsu, Shoko Suzuki, Yoshio Nishimura, Hiromu Saito
Summary: The study found that the birefringence of mixed polycarbonates was lower than pure ones, with differences in modulus and birefringence changes in different transition regions. Wide distortion relaxation in the blends might be due to dynamic asymmetry, leading to faster orientation relaxation and lower birefringence than the component polymers.
Article
Physics, Fluids & Plasmas
Lili Zeng, Walter W. Reisner
Summary: In this study, molecular dynamics simulation was used to investigate the nonequilibrium physics of single nanochannel-confined semiflexible polymers in a homogeneous flow field. The results showed that the flow-based compression of the polymer against the end of the nanochannel led to a distinct organization of folds and circular coils. The organization varied with the stiffness of the chains and the flow speed, but was ultimately determined by the minimization of the total chain free energy.
Article
Biochemistry & Molecular Biology
Valeria Stagno, Chiara Genova, Nicole Zoratto, Gabriele Favero, Silvia Capuani
Summary: This study investigated the potential of PVA-borax hydrogel for cleaning limestones and found that the cleaning effectiveness strongly depends on the porosity of the stones. Different responses were observed in Lecce stone, Travertine perpendicular cut, and Travertine parallel cut, suggesting that the effectiveness of the cleaning varies based on the type of rock.
Article
Polymer Science
Yiqing Wang, Xiao Tan, Adil Usman, Yuhao Zhang, Michal Sawczyk, Petr Kral, Cheng Zhang, Andrew K. Whittaker
Summary: A major challenge in the preparation of polymeric F-19 MRI contrast agents is signal attenuation caused by reduced segmental mobility of partly fluorinated polymers. This study focuses on the role of hydrophilic segments in imaging performance and explores the effect of different hydrophilic segments on F-19 imaging. The results highlight the importance of maintaining high fluorine visibility and long T-2 relaxation time for effective CAs.
Article
Engineering, Chemical
Anastasia Penkova, Anna Kuzminova, Mariia E. Dmitrenko, Victoria A. Surkova, Vladislav P. Liamin, Denis A. Markelov, Andrei Komolkin, Daria Y. Poloneeva, Anastasia Laptenkova, Artem A. Selyutin, Anton S. Mazur, Alexei Emeline, Sabu Thomas, Sergey S. Ermakov
Summary: The study successfully developed highly methanol-permeable pervaporation membranes through modification of polymer membranes and preparation of supported membranes, achieving optimal industrial performance characteristics in the experiment.
SEPARATION AND PURIFICATION TECHNOLOGY
(2021)
Review
Polymer Science
Denis A. Markelov, Anna S. Semisalova, Mikhail A. Mazo
Summary: Dendrimers are tree-like symmetric macromolecules with unique properties, attracting researchers' interest. Differences in structure and conformation can be influenced by solvent selectivity and compatibility of terminal and core groups, leading to the formation of regions with lower polymer density inside the dendrimer.
MACROMOLECULAR CHEMISTRY AND PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Mariia Dmitrenko, Anna Kuzminova, Andrey Zolotarev, Vladislav Liamin, Denis Markelov, Konstantin Semenov, Tatiana Plisko, Alexandr Bildyukevich, Anastasia Penkova
Summary: The study focused on developing novel pervaporation membranes for dehydration, utilizing a blend of hydroxyethyl cellulose (HEC)/polyvinyl alcohol (PVA) and fullerene derivatives. The optimized cross-linked membrane showed promising transport properties in the pervaporation dehydration of isopropanol, with high water content in the permeate.
JOURNAL OF MATERIALS RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Thomas Guerin, Maxim Dolgushev, Olivier Benichou, Raphael Voituriez
Summary: The authors analyzed the kinetics of imperfect reactions in confining domains for diffusive or anomalous transport processes, and found that the full distribution of reaction times can be obtained from the mean reaction time in large confining volumes. They showed that the distribution of imperfect reactions is similar to that of perfect reactions, even in the regime of low reactivity where there are large fluctuations in reaction time. This was illustrated for both normal diffusion in domains of generic shapes and anomalous diffusion in complex environments, with predictions confirmed by numerical simulations.
COMMUNICATIONS CHEMISTRY
(2021)
Article
Engineering, Chemical
Mariia Dmitrenko, Anna Kuzminova, Andrey Zolotarev, Denis Markelov, Andrei Komolkin, Evgeniia Loginova, Tatiana Plisko, Katsiaryna Burts, Alexandr Bildyukevich, Anastasia Penkova
Summary: This study focuses on improving the performance of polyacrylonitrile (PAN) membranes in ultrafiltration through the introduction of TiO2 particles. Different methods of TiO2 immobilization have varying effects on the structure and performance of PAN membranes.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Nadezhda N. Sheveleva, Irina I. Tarasenko, Mikhail A. Vovk, Mariya E. Mikhailova, Igor M. Neelov, Denis A. Markelov
Summary: This paper studies two lysine-based peptide dendrimers with Lys-His-Arg and Lys-Arg-His repeating units and terminal lysine groups. The combination of histidine and arginine in these dendrimers could be important for biomedical applications, such as preventing dendrimer aggregation and facilitating dendrimer penetration through cell membranes. The synthesis of these dendrimers is described, and their structure is confirmed using 1D and 2D Nuclear Magnetic Resonance (NMR) spectroscopy. NMR spectroscopy and relaxation are used to investigate the structural and dynamic properties of these dendrimers and compare them with previously studied dendrimers with Lys-2Arg and Lys-2His repeating units. The results show that both Lys-His-Arg and Lys-Arg-His dendrimers exhibit pH-sensitive conformation and dynamics. The Lys-His-Arg dendrimer, which has a similar conformation to the more hydrophobic Lys-2His dendrimer, could be a more suitable candidate as a pH-sensitive nanocontainer for drug delivery compared to Lys-2His and Lys-Arg-His dendrimers.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Multidisciplinary Sciences
Leo Regnier, Maxim Dolgushev, S. Redner, Olivier Benichou
Summary: The territory explored by a random walk can be quantified by the number of distinct sites visited. We introduce a fundamental quantity, tau(n), which is the time required by a random walk to find a previously unvisited site after visiting n distinct sites, encompassing the dynamics of visitation statistics. We develop a theoretical approach using a mapping with a trapping problem to study it, and find that the distribution of tau(n) can be accounted for by simple analytical expressions, applicable to various diffusion processes.
NATURE COMMUNICATIONS
(2023)
Article
Polymer Science
Nadezhda N. Sheveleva, Andrei V. Komolkin, Denis A. Markelov
Summary: In this study, the shear-stress relaxation of second generation PAMAM and PPI dendrimer melts was investigated through atomistic molecular dynamics simulation. The time dependences of relaxation modulus G(t) and the frequency dependences of storage G'(omega) and loss G''(omega) moduli were obtained and compared with a similar dendrimer of the same generation. The results showed that the chemical structure of the dendrimer segments strongly influenced their mechanical relaxation, with hydrogen bonding in PAMAM dendrimers leading to entanglement of macromolecules and slowing down of mechanical relaxation and rotational diffusion.
Article
Polymer Science
Anna Kuzminova, Mariia Dmitrenko, Andrey Zolotarev, Denis Markelov, Andrei Komolkin, Roman Dubovenko, Artem Selyutin, Jiangjiexing Wu, Rongxin Su, Anastasia Penkova
Summary: Membrane technology is actively developing in modern societies, allowing for the separation of various mixtures in industrial tasks. This study focuses on the development of effective membranes based on PVDF by modifying it with different nanoparticles. Two types of membranes were developed: dense membranes for pervaporation and porous membranes for ultrafiltration. The optimal nanoparticle content in the PVDF matrix was determined. The properties of these membranes were studied using various techniques, and the transport properties of the membranes were evaluated.
Article
Chemistry, Physical
Vladimir Y. Bazaikin, Andrei Komolkin, Denis A. Markelov
Summary: By modifying polymer membranes with special nanoparticles, the transport properties can be improved, resulting in higher efficiency in the separation and purification of mixtures.
JOURNAL OF MOLECULAR LIQUIDS
(2023)
Article
Chemistry, Physical
Naira R. Khusnutdinova, Denis A. Markelov
Summary: The translation mobility of poly(butylcarbosilane) dendrimers in a chloroform solution is studied using molecular dynamics simulations. Traditional methods for calculating the diffusion coefficient and hydrodynamic radius (Rh) of dendrimers often face difficulties and yield incorrect results. By considering rotational diffusion, an Rh similar to experimental data is obtained, which is practically independent of simulation parameters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Naira R. Khusnutdinova, Denis A. Markelov
Summary: In this study, the translational mobility of poly(butylcarbosilane) dendrimers in chloroform solution was investigated using molecular dynamics simulations. Different methods for estimating the hydrodynamic radius (Rh) of dendrimers were discussed, and it was found that considering rotational diffusion provides accurate results independent of simulation box size and other parameters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Physics, Fluids & Plasmas
Leo Regnier, Maxim Dolgushev, S. Redner, Olivier Benichou
Summary: We develop a framework to determine the statistical behavior of the probability of visiting distinct sites at different times in the theory of random walks. We show that the visitation statistics of one-dimensional random walks are temporally correlated and quantify the non-Markovian nature of the process. We apply these ideas to the two-time trapping problem and the visitation statistics of run-and-tumble particle and biased random walk.
Article
Chemistry, Physical
Nadezhda N. Sheveleva, Maxim Dolgushev, Erkki Lahderanta, Denis A. Markelov
Summary: Functionalizing the internal structure of dendrimers can result in changes in their properties. This study investigates the rheological behavior of functionalized dendrimer melts and finds that functionalized dendrimers behave like colloidal particles in crowded environments.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
