物理最新文献

{"title":"Molecular Dynamics Modeling of Pharmacological Vector-Receptor Pairs for Specific Drug Delivery to the Tumor: Atomic/Molecular Mechanisms of RGD Peptide Embedding in the Integrin αvβ3 Receptor","authors":"I. A. Baigunov,&nbsp;Kh. T. Kholmurodov,&nbsp;M. A. Khusenzoda,&nbsp;E. D. Gribova,&nbsp;N. A. Polotnyanko,&nbsp;I. V. Mukhina,&nbsp;P. P. Gladyshev,&nbsp;A. A. Lipengolts","doi":"10.1134/S0006350925700472","DOIUrl":"10.1134/S0006350925700472","url":null,"abstract":"<div><p>Computer-based molecular dynamics studies of the interaction of the pharmacological pair “vector–receptor” have been carried out to simulate promising mechanisms and processes of specific drug delivery to the tumor. The purpose of computational calculations is the description of interaction processes and the determination of the spatial positions of the RGD peptide + integrin α_vβ₃ receptor system, solvated with water. The configuration positions of the RGD peptide + integrin α_vβ₃ system in 100 ns relaxed states were obtained from molecular dynamics modeling. Two RGD peptides located outside and inside the integrin α_vβ₃ receptor were modeled. One of them is a peptide of the original PDB file localized inside the integrin α_vβ₃ receptor. The other RGD peptide is located outside the receptor in its initial position, freely diffuses throughout the entire area of the modeling cell, and naturally comes into contact and binds to integrin α_vβ₃.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"70 3","pages":"407 - 422"},"PeriodicalIF":4.033,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145327618","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":"Femtosecond laser burst mode combined with wet etching for fabricating surface microholes on sapphire","authors":"Xiang Jiang,&nbsp;Xiaojin Xu,&nbsp;Haibo Zhou,&nbsp;Cong Wang,&nbsp;Xianshi Jia,&nbsp;Yulong Ding,&nbsp;Zheng Gao,&nbsp;Shiyu Wang,&nbsp;Linpeng Liu,&nbsp;Ji’an Duan","doi":"10.1007/s00339-025-09029-1","DOIUrl":"10.1007/s00339-025-09029-1","url":null,"abstract":"<div><p>The high-efficiency and high-quality fabrication of submicron-precision microholes on sapphire and other ultra-hard materials constitutes a challenging task due to uncontrollable surface damage and difficulty in enhancing microhole depth. Herein, a hybrid approach combining femtosecond laser burst mode with wet chemical etching is proposed, achieving high-quality microhole fabrication at a rate of 4,000 holes per second. Through modulation of burst pulse quantity, the microhole depth is enhanced from 701 to 1140 nm while maintaining processing efficiency. Wet chemical etching with HF is employed to eliminate particulate residues and debris generated during laser processing. The evolution of microhole profile morphology and surface quality under varying etching durations is systematically investigated. Optimal solution concentration and processing time for sapphire laser-induced micro/nano structure etching have been determined. After etching, the surface roughness is reduced from 64.8 nm to 1.4 nm. Compared with single-pulse, the aspect ratio of burst mode is increased from 0.51 to 0.69. Moreover, it has been demonstrated that, with sufficient etching, the Burst mode can also achieve regular microholes comparable to those produced by single-pulse processing. This femtosecond laser burst mode coupled with wet chemical etching demonstrates effectiveness and universality, establishing a viable technical pathway for high-efficiency fabrication of high-quality microholes with submicron precision.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 11","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316558","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}

{"title":"Theoretical modeling of network topology, rigidity, and electronic structure in quaternary Se₆₅Ge₁₄₊₁₋ₓSb₂₀Teₓ chalcogenide glasses","authors":"S. A. Fayek,&nbsp;A. I. Sharshir,&nbsp;Maha Abdallah Alnuwaiser,&nbsp;Foziah F. Al-Fawzan,&nbsp;Mahmoud G. A. Saleh,&nbsp;Mohamed Mohamady Ghobashy","doi":"10.1007/s00339-025-08939-4","DOIUrl":"10.1007/s00339-025-08939-4","url":null,"abstract":"<div><p>Chalcogenide glasses based on Ge–Se–Sb–Te systems are of great interest for advanced photonic and memory device applications due to their tunable optical, thermal, and structural properties. These glasses offer exceptional infrared transparency, high refractive index, and photo-induced switching behavior, making them promising candidates for phase-change memory and infrared optics. However, understanding how compositional variations, particularly the addition of tellurium (Te), influence network topology, rigidity, and electronic structure remains a key scientific challenge. In this work, a series of Se₆₅Ge₁₄₊₁₋ₓSb₂₀Teₓ glasses (x = 0, 1, 3, and 5 at%) were synthesized using the melt-quenching technique and systematically investigated through theoretical modeling and structural analysis. The aim was to explore how Te incorporation affects the average coordination number, mechanical constraints, cohesive energy, optical band gap, and thermal stability. Detailed calculations of constraint theory parameters (N_con, ⟨r_eff⟩), floppy mode fraction, lone-pair electron concentration, and bond energetics were performed to assess the topological and electronic transformations within the glass matrix. The results reveal that increasing Te content reduces the average coordination number and cohesive energy, indicating a softening of the glass network. At x = 5, the system reaches the isostatic threshold (N_con ≈ 3), maximizing network flexibility without compromising stability. This composition’s substantial increase in glass transition temperature (Tg ≈ 988 K) and mean bond energy (⟨E⟩ ≈ 4.12 eV/atom) suggests the formation of a thermally robust yet topologically optimized structure. Concurrently, the optical band gap narrows slightly, and the system retains high covalent character (&gt; 99% in Te–Se bonds), ensuring desirable transparency and electronic performance.</p></div>","PeriodicalId":473,"journal":{"name":"Applied Physics A","volume":"131 11","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316562","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}

{"title":"Cycloastragenol Exerts an Antiapoptotic Effect on Human Lymphocytes under UV-Irradiation","authors":"M. A. Nakvasina,&nbsp;V. G. Artyukhov,&nbsp;M. G. Holyavka,&nbsp;I. A. Koltakov,&nbsp;E. I. Korpusova,&nbsp;N. G. Saraji","doi":"10.1134/S0006350925700575","DOIUrl":"10.1134/S0006350925700575","url":null,"abstract":"<div><p>Changes in the levels of some markers of apoptosis (lipid asymmetry of plasma membranes, production of reactive oxygen species, nitric oxide, and the concentration of ionized calcium) of human blood lymphocytes modified by exposure to hydrogen peroxide (10^–5 mol/L) and UV light (254 nm, 1510 J/m²) in the presence of cycloastragenol (10^–8–10^–5 mol/L) were studied. The intensity of apoptotic lymphocyte death processes was found to decrease after UV-light exposure in the presence of cycloastragenol (10^–8 mol/L). The cytoprotective effect of cycloastragenol on lymphocytes was found to be due to a decrease in the level of intracellular reactive oxygen species and calcium ions and an increase in the activity of catalase and glutathione reductase and nitric oxide production. Possible mechanisms of cycloastragenol action as a regulator of apoptotic death of lymphocytes induced by UV radiation and hydrogen peroxide exposure are discussed.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"70 3","pages":"543 - 552"},"PeriodicalIF":4.033,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145327552","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":"Identification of Potential SOX2 Binding Sites to Nucleosomes via Molecular Modeling","authors":"T. A. Romanova,&nbsp;D. M. Ryabov,&nbsp;G. A. Komarova,&nbsp;A. K. Shaytan,&nbsp;G. A. Armeev","doi":"10.1134/S0006350925700460","DOIUrl":"10.1134/S0006350925700460","url":null,"abstract":"<div><p>The pioneer SOX2 transcription factor plays an important role in the regulation of gene expression by binding to condensed chromatin and inducing its decondensation. Experimental data on the preferred positions of SOX2 binding to DNA in the context of the nucleosome are contradictory: in some studies, binding to the inner segments of nucleosomal DNA is preferred, in others it binds to the edge segments. In the framework of this work, all possible variants of SOX2 binding to nucleosomal DNA at different distances from the nucleosome center (determined by the superhelix position parameter, SHL) and different orientations of the binding site relative to the nucleosome center (determined by the SHL sign) were analyzed by molecular modeling. It was shown that on an intact nucleosome binding is possible at positions SHL +2, SHL ±4, and SHL ±5, but if we assume a shift of nucleosomal DNA by one pair of nucleotides, binding becomes possible at positions corresponding to all integer values of the SHL. This observation helps to explain some of the contradictions between the experimental data.</p></div>","PeriodicalId":493,"journal":{"name":"Biophysics","volume":"70 3","pages":"394 - 406"},"PeriodicalIF":4.033,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145327613","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":"Long lived quasinormal modes in the effective quantum gravity","authors":"S. V. Bolokhov","doi":"10.1140/epjc/s10052-025-14883-7","DOIUrl":"10.1140/epjc/s10052-025-14883-7","url":null,"abstract":"<div><p>Two models for Schwarzschild-like black holes with quantum corrections, derived from the Hamiltonian constraints approach to quantum gravity while preserving general covariance, have been developed in Zhang et al. (Phys. Rev. D <b>111</b>, L081504, 2025, arXiv:2407.10168 [gr-qc]). In this work, we study the quasinormal modes of a massive scalar field and demonstrate that the spectrum includes arbitrarily long-lived modes, known as quasi-resonances. Precise calculations using the Leaver method show good agreement with WKB data and time-domain integration within the range where these methods are reliable, specifically for small field masses.</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14883-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-radial oscillations and gravitational wave radiation of proto-neutron stars","authors":"Yi-Lun Tao,&nbsp;Zi-Yue Zheng,&nbsp;Ting-Ting Sun,&nbsp;Huan Chen,&nbsp;Jin-Biao Wei","doi":"10.1140/epja/s10050-025-01711-5","DOIUrl":"10.1140/epja/s10050-025-01711-5","url":null,"abstract":"<div><p>We study the <i>g</i>-mode non-radial oscillations of proto-neutron stars during the cooling stage. Based on finite-temperature extended Brueckner–Hartree–Fock theory and the relativistic mean-field theory, and combined with appropriate crust equations of state, we construct isentropic equations of state for proto-neutron stars with neutrino trapping. Under the frozen-fluid assumption during oscillations, the difference between the adiabatic and equilibrium sound speeds gives rise to nonzero Brunt–Väisälä frequencies, which enables the existence of <i>g</i>-mode oscillations. We then study the effects of temperature and neutrino trapping on the <i>g</i>-mode frequencies under the Cowling approximation, making comparisons between results with the two EOSs and examining the impact of varying crust equations of state. Our results show that, compared with cold neutron stars, neutrino trapping significantly reduces gravity-mode frequencies in both models, and the relativistic mean-field model systematically yields lower frequencies than the Brueckner–Hartree–Fock model. Neutrino trapping also prolongs gravitational wave damping times and reduces the strain amplitudes, but predictions indicate that the signals remain within the sensitivity of current and future detectors. These findings highlight the potential of gravitational wave observations to probe the interior physics of proto-neutron stars.</p></div>","PeriodicalId":786,"journal":{"name":"The European Physical Journal A","volume":"61 10","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316144","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":"Tunable mechanical, opto-electronic, and thermoelectric properties of ( Sr_2NbXO_6( X = Al, ) In,  and Tl) double perovskites as a sustainable energy application: insights from first-principles calculations","authors":"K. Elasri,&nbsp;A. Boufoud,&nbsp;E. Darkaoui,&nbsp;S. El asri,&nbsp;S. Mouslih,&nbsp;A. Abbassi,&nbsp;S. Taj,&nbsp;A. Fahmi,&nbsp;B. Manaut","doi":"10.1140/epjb/s10051-025-01067-1","DOIUrl":"10.1140/epjb/s10051-025-01067-1","url":null,"abstract":"<p>Using density functional theory (DFT), we investigated the mechanical, optoelectronic, and thermoelectric properties of the double perovskites <span>(Sr_{2}NbXO_{6} (X = Al, In, text {and}~Tl))</span>. Calculations of the formation energy, cohesion energy, tolerance factor (<span>(tau )</span>), as well as the analysis of the Born–Huang approximation stability criteria, confirm the thermodynamic and mechanical stability of these compounds. Electronic properties show that the compounds <span>(Sr_{2}NbInO_{6})</span> and <span>(Sr_{2}NbTlO_{6})</span> have an indirect band gap with values of 3.43 <i>eV</i> and 2.60 <i>eV</i>,  respectively. In contrast, <span>(Sr_{2}NbAlO_{6})</span> has a direct band gap of 3.69 <i>eV</i>. An analysis of the optical properties, including the real and imaginary parts of the dielectric function <span>((varepsilon _1, varepsilon _2))</span>, the absorption coefficient <span>(alpha (omega ))</span>, the refractive index <span>(n(omega ))</span>, the optical conductivity <span>(sigma (omega ))</span>, and the reflectivity <span>(R(omega ))</span>, was also performed. The results reveal significant absorption of incident light in the ultraviolet (UV) region, indicating that these oxides have strong potential for use in UV optical sensors as well as in various other UV-based optoelectronic devices. Furthermore, the <i>BoltzTraP2</i> code reveals promising values for the Seebeck coefficient, electrical and thermal conductivity, power factor, and figure of merit (ZT). These findings suggest that <span>(Sr_2NbXO_6)</span> compounds are suitable candidates for sustainable energy technologies, particularly in thermoelectric and UV sensor devices.</p>","PeriodicalId":787,"journal":{"name":"The European Physical Journal B","volume":"98 10","pages":""},"PeriodicalIF":1.7,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Dynamics of chemoreceptor activity with time-periodic attractant field","authors":"Ramesh Pramanik,&nbsp;Ramu K. Yadav,&nbsp;Sakuntala Chatterjee","doi":"10.1140/epje/s10189-025-00525-z","DOIUrl":"10.1140/epje/s10189-025-00525-z","url":null,"abstract":"<p>When exposed to a time-periodic chemical signal, an <i>E.coli</i> cell responds by modulating its receptor activity in a similar time-periodic manner. But there is a phase lag between the applied signal and activity response. We study the variation of activity amplitude and phase lag as a function of applied frequency <span>(omega )</span>, using numerical simulations. The amplitude increases with <span>(omega )</span>, reaches a plateau and then decreases again for large <span>(omega )</span>. The phase lag increases monotonically with <span>(omega )</span> and finally saturates to <span>(3 pi /2)</span> when <span>(omega )</span> is large. The activity is no more a single-valued function of the attractant signal, and plotting activity vs attractant concentration over one complete time period generates a loop. We monitor the loop area as a function of <span>(omega )</span> and find two peaks for small and large <span>(omega )</span> and a sharp minimum at intermediate <span>(omega )</span> values. We explain these results from an interplay between the timescales associated with adaptation, activity switching and applied signal variation. In particular, for very large <span>(omega )</span> the quasi-equilibrium approximation for activity dynamics breaks down, which has not been explored in earlier studies. We perform analytical calculation in this limit and find good agreement with our simulation results.</p>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"48 10-12","pages":""},"PeriodicalIF":2.2,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Observational properties of a Schwarzschild black hole surrounded by a Dehnen-type dark matter halo","authors":"Zhi Li,&nbsp;Jiancheng Yu","doi":"10.1140/epjc/s10052-025-14911-6","DOIUrl":"10.1140/epjc/s10052-025-14911-6","url":null,"abstract":"<div><p>This study investigates the accretion process and observational signatures of thin accretion disks around a Schwarzschild black hole (BH) embedded in a Dehnen-type dark matter (DM) halo. We examine the influence of the density <span>(rho _{s})</span> and radius <span>(r_{s})</span> of the DM halo on key disk properties, including the energy flux, temperature distribution, and emission spectrum. Our results show that all three of these quantities decrease with increasing <span>(rho _{s})</span> or <span>(r_{s}.)</span> Furthermore, by generating and analyzing both direct and secondary images of the accretion disk, we explore how the observational inclination angle and the DM halo parameters <span>(rho _{s})</span> and <span>(r_{s})</span> affect image profiles. Finally, the observed flux distributions are presented for different inclination angles. Our findings indicate that the accretion disk becomes colder and dimmer as the DM halo parameters increase, highlighting the significant role of DM in shaping BH observables.\u0000</p></div>","PeriodicalId":788,"journal":{"name":"The European Physical Journal C","volume":"85 10","pages":""},"PeriodicalIF":4.8,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjc/s10052-025-14911-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145316145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}