物理最新文献

{"title":"Adsorption of Proteins onto Nitrocellulose Membranes from a Flowing Solution – Theory and Experiment","authors":"K. A. Prusakov,&nbsp;S. V. Zamalutdinova,&nbsp;A. E. Sidorova,&nbsp;D. V. Bagrov","doi":"10.1134/S0006350924700908","DOIUrl":"10.1134/S0006350924700908","url":null,"abstract":"<p>Some analytical laboratory procedures involve passing the sample through a porous polymer membrane. In this process, the analyte binds to the surface of the membrane modified with a specific receptor layer and is then detected using optical or electrochemical signals. This paper presents an experimental and theoretical analysis of the binding patterns of the analyte with nitrocellulose membranes. Two cases are considered: specific binding of the analyte with antibodies immobilized on the membrane, as well as non-specific adsorption of the analyte. It is shown that increasing the volume of the sample passed through the membrane leads to an increase in the amount of adsorbed analyte, which can generally be used to improve the sensitivity of biosensors.</p>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"820 - 827"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Models of Flowering Gene Networks and their Adaptation for the Analysis of Vernalization Mechanisms in Legumes","authors":"V. V. Gursky,&nbsp;M. A. Duk,&nbsp;M. P. Bankin,&nbsp;M. G. Samsonova,&nbsp;S. Yu. Surkova","doi":"10.1134/S0006350924700994","DOIUrl":"10.1134/S0006350924700994","url":null,"abstract":"<div><p>Flowering time is the most important agronomic trait used in breeding and determining yield. Vernalization, or long-term exposure to cold, accelerates flowering and increases the yields of many crops. The molecular mechanisms of the effect of vernalization on the transition to flowering have been studied well in <i>Arabidopsis thaliana</i>, but remain largely unclear for legumes. Mathematical modeling is an effective tool for identifying regulatory interactions in gene networks based on gene expression data. In this review, we consider previously developed approaches to modeling gene networks of flowering and the prospects for their adaptation to analyze the mechanisms of vernalization in legumes.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"899 - 904"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performing Floquet stability test for AEPs and exploring pulsating ZVCs in the perturbed planar elliptic solar sail problem","authors":"Pulkit Gahlot,&nbsp;Ram Kishor","doi":"10.1140/epjp/s13360-025-06147-w","DOIUrl":"10.1140/epjp/s13360-025-06147-w","url":null,"abstract":"<div><p>The study of stability properties of equilibrium points is a key task to know the behaviour of a dynamical system, in space. This paper deals about a perturbed solar sail problem under the frame of planar elliptic restricted three-body problem in the context of artificial equilibrium points (AEPs), pulsating zero velocity curves (ZVCs) and Floquet stability analysis. First, the proposed problem is formulated under the influence of oblateness of both the primaries, sail lightness number and presence of a disc with density profile and all the AEPs are determined. It is found that due to these perturbations, positions of all the AEPs either shift towards the origin or move away from it. Further, pulsating ZVCs are estimated by establishing an invariant relation and it is seen that impacts of the assumed perturbing factors are very less on the prohibited zones for the motion solar sail. Finally, Floquet stability analysis is performed for all the AEPs with the help of characteristic exponents and transition curves. It is observed that changes in the values of perturbing parameters cause changes in the stability regions as well as position of the bifurcation point on the <span>(mu)</span>-axis of the transition curve. These results can be utilised to study the more generalised solar sail problem in the presence of other kinds of perturbations.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 3","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Study of the Secondary Structure of a Membrane Protein Bacteriorhodopsin Exposed to Microwaves with a Frequency of 8–18 GHz by Fourier Transform IR Difference Spectroscopy","authors":"E. L. Terpugov,&nbsp;O. V. Degtyareva,&nbsp;E. E. Fesenko","doi":"10.1134/S0006350924700921","DOIUrl":"10.1134/S0006350924700921","url":null,"abstract":"<div><p>Fourier transform infrared difference spectroscopy was used to study the effect of millimeter-range electromagnetic radiation on the structure of bacteriorhodopsin under lighting conditions. A detailed analysis of the Fourier IR spectra revealed pronounced structural changes in the region of amide I, amide II and rearrangement of the hydrogen bond network. The well-resolved peaks of the amide bands made it possible to recognize two different components (α-I and α-II) of the α-helical conformation of the opsin. Irreversible conformational changes of bacteriorhodopsin in purple membranes detected by Fourier IR difference spectroscopy suggested that microwaves induced structural rearrangements of proteins unrelated to temperature.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"836 - 845"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of Binding Affinity in the Complexes of ACE2 with RBD of the S Protein of SARS-CoV Using Convolutional Neural Networks","authors":"E. A. Bogdanova,&nbsp;A. V. Chernukhin,&nbsp;K. V. Shaitan,&nbsp;V. N. Novoseletsky","doi":"10.1134/S0006350924700933","DOIUrl":"10.1134/S0006350924700933","url":null,"abstract":"<div><p>The experimentally obtained structures of 48 ACE 2 receptor complexes with RBD of the S protein of the SARS-CoV and SARS-CoV-2 coronaviruses (including mutant forms of the latter) were evaluated, for which the dissociation constants were calculated. To predict the binding affinity, the ProBAN neural network algorithm developed by the authors earlier was used, as well as a number of other Gibbs free energy estimation algorithms: Prodigy, FoldX, DFIRE, and RosettaDock. A comparison of the evaluation results showed that ProBAN demonstrated the best prediction quality (Pearson correlation coefficient was 0.56 and the mean absolute error was 0.7 kcal/mol). The results we obtained suggested a better quality of affinity prediction for other protein–protein complexes as well. Information about the studied complexes and the prediction results are available in the repository at the link: https://github.com/EABogdanova/ProBAN_RBD-ACE2.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"846 - 856"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of a Polysaccharide from Helianthus tuberosus L. on the Antiproliferative Activity of the N-Glycoside Indolo[2,3-a]carbazole Derivative LCS-1269","authors":"M. P. Kiseleva,&nbsp;I. S. Golubeva,&nbsp;V. P. Deryagina,&nbsp;A. V. Lantsova,&nbsp;L. V. Ektova,&nbsp;E. A. Kornyushenkov,&nbsp;L. M. Borisova,&nbsp;E. A. Generalov","doi":"10.1134/S0006350924701045","DOIUrl":"10.1134/S0006350924701045","url":null,"abstract":"<div><p>The antitumor activity of the N-glycoside derivative indolo[2,3-a]carbazole LCS-1269 with a polysaccharide from <i>Helianthus tuberosus</i> L. as an adjuvant agent was studied on a model of Lewis epidermoid lung carcinoma in mice of F1 hybrids (C₅₇Bl/₆ × DBA/₂). The antitumor effect was assessed by inhibition of tumor growth in treated animals in comparison with controls. As a result, it was found that the therapeutic effect of the combination was higher and longer than in monotherapy, with a decrease in tumor growth of Lewis lung carcinoma by 53–64% up to 28 days of follow-up. The use of the polysaccharide led to an increase in the number of blood cells, leukocytes, lymphocytes, and phagocytes responsible for antitumor immunity. The chemotherapeutic effect of the combination of LCS-1269 and polysaccharide showed a pronounced stable antitumor response against Lewis lung carcinoma in the peripheral blood system of mice with a temporary increase in the number of neutrophils and monocytes on the 12th day of tumor development. The tested compounds obviously stimulated the proliferation of certain phenotypes of neutrophils and monocytes with antitumor activity at an earlier stage of Lewis lung carcinoma development.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"966 - 973"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Assessment of the Force Characteristics of the Interaction of the Yersinia pseudotuberculosis Lipopolysaccharide with Antibodies by Optical Trapping and Atomic Force Microscopy","authors":"A. A. Byvalov,&nbsp;V. S. Belozerov,&nbsp;I. V. Konyshev,&nbsp;B. A. Ananchenko","doi":"10.1134/S000635092470091X","DOIUrl":"10.1134/S000635092470091X","url":null,"abstract":"<div><p>A comparative assessment of the binding force of lipopolysaccharide from <i>Yersinia pseudotuberculosis</i> culture with monoclonal antibodies has been carried out using optical tweezers and atomic force microscopy. The features of the two techniques are discussed, which detected significant differences in the measured bond rupture force between a lipopolysaccharide-sensitized probe (a polystyrene microsphere in the case of optical tweezers and a silicon nitride cantilever tip in the case of atomic force microscopy) and a substrate (glass and mica, respectively) coated with monoclonal antibodies. In the case of atomic force microscopy, the tip of the cantilever slides along the surface of the substrate until the piezo stage stops, causing a change in the spatial structure of the sensitins and, as a result, a redistribution of the multiple bonds between the lipopolysaccharide agglomerate and antibodies. When the optical tweezers technique is used there is no significant displacement of the microsphere along the substrate surface and, unlike atomic force microscopy, the rupture of the complex bond between lipopolysaccharide and complementary antibodies is recorded as a single and short-term (1–2 ms) jump in the photodetector signal. The fixed values of the bond rupture force measured by both techniques are relative and vary depending on the selected experimental conditions. It is shown that the nonspecific component of the bond rupture force measured by atomic force microscopy is significantly higher than that determined by optical tweezers.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"828 - 835"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Presence of Septin Proteins in the Neuromuscular Junction of Somatic Muscle in the Earthworm Lumbricus terrestris","authors":"L. F. Nurullin,&nbsp;E. M. Volkov","doi":"10.1134/S0006350924700969","DOIUrl":"10.1134/S0006350924700969","url":null,"abstract":"<div><p>Fluorescent confocal microscopy has shown the presence of the family of septin proteins types 2, 3, 5, 7, and 9 in the somatic muscle of the earthworm <i>Lumbricus terrestris</i>. Septins of types 2 and 9 lack their specific concentration in the cholinergic synapse zone, whereas septins of types 3 and 5, and especially type 7, have a quantitatively expressed binding localization at the zone of the motor end plate. It is assumed that septins of types 3 and 5 and, above all, type 7 may be participants in the mechanisms of modulation of the quantal secretion of the mediator.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"876 - 881"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shock Wave-Induced Permeabilization of Pseudomonas aeruginosa Cell Membranes","authors":"S. N. Letuta,&nbsp;A. T. Ishemgulov,&nbsp;O. K. Davydova,&nbsp;A. N. Nikiyan,&nbsp;M. E. Grigoriev","doi":"10.1134/S0006350924700945","DOIUrl":"10.1134/S0006350924700945","url":null,"abstract":"<div><p>The effect of acoustic shock waves on the permeability of membranes of Gram-negative bacteria of <i>P. aeruginosa</i> for the anionic photosensitizer erythrosine has been studied. Shock waves were generated by rapid local heating of the medium, which occurred during the nonradiative relaxation of high electronically excited states of photosensitizer molecules populated by a high-power density laser pulse. It has been shown that the permeability of bacterial membranes increased under the effect of shock waves and erythrosine penetrated into the cells; this was accompanied by an increase in the efficiency of photodynamic action on microorganisms.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"69 5","pages":"857 - 862"},"PeriodicalIF":4.033,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microwave-assisted rapid synthesis of yttrium iron garnet nano powders: formation mechanism and magnetic properties","authors":"Peng Chen,&nbsp;Min Yang,&nbsp;Yue Wang,&nbsp;Xiayu Liu,&nbsp;Bingbing Wu,&nbsp;Xiaoli Song,&nbsp;Hui Sun,&nbsp;Junliang Liu,&nbsp;Lifeng Zhang","doi":"10.1007/s00339-025-08396-z","DOIUrl":"10.1007/s00339-025-08396-z","url":null,"abstract":"<div><p>Microwave heat treatment has been employed instead of conventional heat treatment to rapidly synthesize yttrium iron garnet (YIG) nano powders based on chemical co-precipitation technique. Pure phase YIG powders can be formed in a short time, only 2 min with microwave heating temperatures above 850^oC. As the microwave heating time was 10 min, the average particle size increased from about 34 to 88 nm. Owing to the microwave activation, the surface magnetic disordered phase content decreased and the powders achieved a high saturation magnetization of 30 emu/g. Taking advantages of microwave heating, the nucleation of YIG is promoted, and owing to the activated diffusion and chemical reactions in the precursor powders, the uniform growth of YIG particles is established. All these make contributions to the rapid formation of high-quality YIG nano powders.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 4","pages":""},"PeriodicalIF":2.5,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143553723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}