Complex Systems最新文献

{"title":"Fluctuations in Human's Walking (IV)","authors":"T. Obata, T. Mashiyama, T. Kogure, S. Itakura, T. Sato, K. Takahashi, H. Oshima, Hiroaki Hara","doi":"10.1063/1.2897889","DOIUrl":"https://doi.org/10.1063/1.2897889","url":null,"abstract":"A field experiment of ring‐wandering is executed on a wide playground. Blindfolded and stoppled subjects are observed to do ring‐wandering rather than random‐walking. This experiment simulates the phenomenon of ring‐wandering that climbers encounter in snowy mountains. 15 samples of walking for 13 subjects are reported. Their walking periods are about 40 minutes or 2 hours. The walking data are acquired every second, using a GPS receiver. The discrete velocity v(t) and discrete angular velocity ω(t) of the data are analyzed, using Hurst's R/S analysis and Fourier spectrum analysis. The Hurst exponents of v(t) show long‐range correlations. The Hurst exponents of ω(t) show anti‐correlations in short‐ranges and correlations in long‐ranges. These characteristics of the Hurst exponents in the present data in addition to previous data in this study series describe the ring‐wandering phenomena very well. Significant differences are not seen between 40‐minutes walking and 2‐hours walking.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897889","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348315","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":"Liquid Polyamorphism: Some Unsolved Puzzles of Water in Bulk, Nanoconfined, and Biological Environments","authors":"H. Stanley, Pradeep Kumar, G. Franzese, Limei Xu, Zhen-Wei Yan, M. Mazza, S. H. Chen, F. Mallamace, S. Buldyrev","doi":"10.1063/1.2897798","DOIUrl":"https://doi.org/10.1063/1.2897798","url":null,"abstract":"We investigate the relation between changes in dynamic and thermodynamic anomalies arising from the presence of the liquid‐liquid critical point in (i) Two models of water, TIP5P and ST2, which display a first order liquid‐liquid phase transition at low temperatures; (ii) the Jagla model, a spherically symmetric two‐scale potential known to possess a liquid‐liquid critical point, in which the competition between two liquid structures is generated by repulsive and attractive ramp interactions; and (iii) A Hamiltonian model of water where the idea of two length/energy scales is built in; this model also displays a first order liquid‐liquid phase transition at low temperatures besides the first order liquid‐gas phase transition at high temperatures. We find a correlation between the dynamic fragility crossover and the locus of specific heat maxima CPmax (“Widom line”) emanating from the critical point. Our findings are consistent with a possible relation between the previously hypothesized liquid‐liquid phase transition and the transition in the dynamics recently observed in neutron scattering experiments on confined water. More generally, we argue that this connection between CPmax and the dynamic crossover is not limited to the case of water, a hydrogen bonded network liquid, but is a more general feature of crossing the Widom line, an extension of the first‐order coexistence line in the supercritical region. We present evidence from experiments and computer simulations supporting the hypothesis that water displays polyamorphism, i.e., water separates into two distinct liquid phases. This concept of a new liquid‐liquid phase transition is finding application to other liquids as well as water, such as silicon and silica. We also discuss related puzzles, such as the mysterious behavior of confined water and the “skin” of hydration water near a biomolecule. Specifically, using molecular dynamics simulations, we also investigate the relation between the dynamic transitions of biomolecules (lysozyme and DNA) and the dynamic and thermodynamic properties of hydration water. We find that the dynamic transition of the macromolecules, sometimes called a “protein glass transition”, occurs at the temperature of dynamic crossover in the diffusivity of hydration water, and also coincides with the maxima of the isobaric specific heat CP and the temperature derivative of the orientational order parameter. We relate these findings to the hypothesis of a liquid‐liquid critical point in water. Our simulations are consistent with the possibility that the protein glass transition results from a change in the behavior of hydration water, specifically from crossing the Widom line.We investigate the relation between changes in dynamic and thermodynamic anomalies arising from the presence of the liquid‐liquid critical point in (i) Two models of water, TIP5P and ST2, which display a first order liquid‐liquid phase transition at low temperatures; (ii) the Jagla model, a sph","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897798","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58347931","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":"Brillouin and Raman Scattering Study of Ethylene Glycol Aqueous Solutions","authors":"Y. Seshimo, Y. Ike, S. Kojima","doi":"10.1063/1.2897819","DOIUrl":"https://doi.org/10.1063/1.2897819","url":null,"abstract":"We studied the cluster structure of ethylene glycol aqueous solutions by Brillouin and Raman scattering. We measured the ultrasonic sound velocity of the sample by Brillouin scattering. From the concentration dependence of the sound velocity, we studied the cluster structure in the solution. We showed that the number of H2O molecule neighboring a EG molecule becomes a little higher with increasing temperature and the intermolecular interaction between EG and H2O molecules weakened with increasing temperature. In Raman scattering study, We studied the hydrogen bond in the solution using the OD stretching band. We revealed that the strength of the hydrogen bond is independent of the EG concentration.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897819","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348020","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":"A Theory of Electrical Conductivity of Pseudo‐Binary Equivalent Molten Salt","authors":"S. Matsunaga, T. Koishi, S. Tamaki","doi":"10.1063/1.2897825","DOIUrl":"https://doi.org/10.1063/1.2897825","url":null,"abstract":"Many years ago, Sundheim proposed the “universal golden rule” by experiments, i.e. the ratio of the partial ionic conductivities in molten binary salt is equal to the inverse mass ratio of each ions, σ+/σ− = m−/m−. In the previous works, we have proved this relation by the theory using Langevin equation, and by molecular dynamics simulations (MD). In this study, the pseudo binary molten salt NaCl‐KCl system is investigated in the same theoretical framework as previous works as the serial work in molten salts. The MD results are also reported in connection with the theoretical analysis.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897825","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348078","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":"Dynamic crossover phenomenon in confined supercooled water and its relation to the existence of a liquid-liquid critical point in water","authors":"Sow-Hsin Chen, F. Mallamace, Li Liu, Dazhi Liu, Xiang-Qiang Chu, Yang Zhang, Chansoo Kim, A. Faraone, C. Mou, E. Fratini, P. Baglioni, A. Kolesnikov, V. García-Sakai","doi":"10.1063/1.2897826","DOIUrl":"https://doi.org/10.1063/1.2897826","url":null,"abstract":"We have observed a Fragile‐to‐Strong Dynamic Crossover (FSC) phenomenon of the α‐relaxation time and self‐diffusion constant in confined supercooled water. The α‐relaxation time is measured by Quasielastic Neutron Scattering (QENS) experiments and the self‐diffusion constant by Nuclear Magnetic Resonance (NMR) experiments. Water is confined in 1‐d geometry in cylindrical pores of nanoscale silica materials, MCM‐41‐S and in Double‐Wall Carbon Nanotubes (DWNT). The crossover phenomenon can also be observed from appearance of a Boson peak in Incoherent Inelastic Neutron Scattering experiments. We observe a pronounced violation of the Stokes‐Einstein Relation at and below the crossover temperature at ambient pressure. Upon applying pressure to the confined water, the crossover temperature is shown to track closely the Widom line emanating from the existence of a liquid‐liquid critical point in an unattainable deeply supercooled state of bulk water. Relation of the dynamic crossover phenomenon to the existence of a density minimum in supercooled confined water is discussed. Finally, we discuss a role of the FSC of the hydration water in a biopolymer that controls the biofunctionality of the biopolymer.We have observed a Fragile‐to‐Strong Dynamic Crossover (FSC) phenomenon of the α‐relaxation time and self‐diffusion constant in confined supercooled water. The α‐relaxation time is measured by Quasielastic Neutron Scattering (QENS) experiments and the self‐diffusion constant by Nuclear Magnetic Resonance (NMR) experiments. Water is confined in 1‐d geometry in cylindrical pores of nanoscale silica materials, MCM‐41‐S and in Double‐Wall Carbon Nanotubes (DWNT). The crossover phenomenon can also be observed from appearance of a Boson peak in Incoherent Inelastic Neutron Scattering experiments. We observe a pronounced violation of the Stokes‐Einstein Relation at and below the crossover temperature at ambient pressure. Upon applying pressure to the confined water, the crossover temperature is shown to track closely the Widom line emanating from the existence of a liquid‐liquid critical point in an unattainable deeply supercooled state of bulk water. Relation of the dynamic crossover phenomenon to the existence...","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897826","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348089","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":"Viscoelasticity and Dynamics of Single Biopolymer Chain Measured with Magnetically Modulated Atomic Force Microscopy","authors":"M. Kageshima, Y. Nishihara, Y. Hirata, T. Inoue, Y. Naitoh, Y. Sugawara","doi":"10.1063/1.2897846","DOIUrl":"https://doi.org/10.1063/1.2897846","url":null,"abstract":"Viscoelactic response of a titin single molecule chain during the course of forced unraveling was studied using atomic force microscopy. Effect of transition to/from an unfolding intermediate onto the measured elasticity data was analyzed. The result hinted that emergence of the transition onto the elasticity depends on the experimental condition such as modulation force amplitude. Anomalous slow unraveling of one domain was observed and its viscoelastic response was discussed from the viewpoint of internal friction of polymer.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897846","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348184","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":"Radio‐Frequency, Atmospheric‐Pressure Glow Discharges: Producing Methods, Characteristics and Applications in Bio‐Medical Fields","authors":"He-ping Li, Guo Li, Wenting Sun, Sen Wang, Cheng-Yu Bao, Liyan Wang, Ziliang Huang, Nan Ding, Hongxin Zhao, X. Xing","doi":"10.1063/1.2897862","DOIUrl":"https://doi.org/10.1063/1.2897862","url":null,"abstract":"Radio‐frequency (RF), atmospheric‐pressure glow discharge (APGD) plasmas with bare metallic electrodes have shown their promising prospects in different fields. In this paper, based on the induced gas discharge approach, the discharge characteristics of RF, APGD plasmas using helium/oxygen mixture as the plasma working‐gas are presented. The bio‐medical effects of the helium RF APGD plasma jet acting on the gfp DNA and E. coli are also reported. Studies concerning the lethal and sub‐lethal effects of the RF APGDs on the molecular and cell levels, which are related with the characteristics of the plasmas and their operation conditions are necessary in the future work based on a closer cooperation between the researchers in the field of the plasma science & technology and of the bio‐medical science.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897862","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348233","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":"Chain Structures of Microparticles Induced by Focusing a Laser Beam near the Liquid‐Air Interface of a Droplet","authors":"H. Adachi, K. Miyakawa","doi":"10.1063/1.2897886","DOIUrl":"https://doi.org/10.1063/1.2897886","url":null,"abstract":"We investigate optically induced dynamics of micron‐sized particles by focusing a laser beam near the liquid‐air interface of a suspension droplet. We find three distinct regimes in behaviors of particles depending on the contact angle of the droplet: convection, linear flow and formation of a closed‐packed array. These behaviors are governed by the most dominant of effects arising from a focused laser beam, such as local heating and radiation pressure. We find that micron‐sized polystyrene beads can be assembled into a chain structure by taking advantage of linear flows. This novel method is applicable to the formation of a chain of carbon nanotubes, non‐transparent objects which are difficult to trap.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897886","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348289","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":"Explanation of Correlation between Adjacent Vertices in Network Formed by Traces of Random Walkers","authors":"N. Ikeda","doi":"10.1063/1.2897891","DOIUrl":"https://doi.org/10.1063/1.2897891","url":null,"abstract":"We investigated certain kinds of vertex correlation in networks formed by traces of random walkers. In this paper, the sign of correlation between degree and local clustering on adjacent vertices is interpreted based on the capacity for new creation of links for highly connected vertices. These interpretations are consistent with numerical simulation of network evolution. Other types of correlation can be related with each other. It is interesting that the local rules of network evolution determined by the movement of random walkers naturally provide large clustering coefficients and various finite vertex correlations.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897891","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58348325","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":"Effectiveness of Slow Relaxation Dynamics in Finite-Time Optimization by Simulated Annealing","authors":"M. Hasegawa","doi":"10.1063/1.2897906","DOIUrl":"https://doi.org/10.1063/1.2897906","url":null,"abstract":"The origin of the specific temperature beneficial to finite‐time optimization by simulated annealing is discussed on the analogy of the dynamics of complex physical systems. Rate‐cycling experiments are introduced and performed on practical time scales on the random Euclidean traveling salesman problems. In the present systems, the effective relaxation dynamics and the resulting good optimization performance are not only dependent on but also sensitive to the search around an intermediate temperature. This influential temperature is understood to be determined from the temperature dependence of the Deborah number used to identify glass transition.","PeriodicalId":46935,"journal":{"name":"Complex Systems","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2008-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1063/1.2897906","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58347961","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}