On the general concept of buoyancy in sedimentation and ultracentrifugation.

abstract：:Folate deficiency is accompanied by a decline in the cognitive neurotransmitter acetylcholine and a decline in cognitive performance in mice lacking apolipoprotein E (ApoE-/- mice), a low-density lipoprotein that regulates aspects of lipid metabolism. One direct consequence of folate deficiency is a decline in S-adeno...

journal_title：Physical biology

authors： Serra M,Chan A,Dubey M,Gilman V,Shea TB

更新日期：2008-12-19 00:00:00

abstract：:Lipid molecules, structural components of biomembranes, have been proposed for an important role in membrane fusion. Through various techniques based on a protein-reconstituted vesicle-vesicle fusion system, we investigated the influence of several lipid molecules on different stages of a yeast soluble N-ethylmaleimid...

journal_title：Physical biology

authors： Lai Y,Zhao L,Bu B,Lou X,Li D,Ji B,Liu J,Diao J,Shin YK

更新日期：2015-04-21 00:00:00

abstract：:Cells of the immune system are confronted with opposing pro- and anti-inflammatory signals. Dendritic cells (DC) integrate these cues to make informed decisions whether to initiate an immune response. Confronted with exogenous microbial stimuli, DC endogenously produce both anti- (IL-10) and pro-inflammatory (TNFα) cu...

journal_title：Physical biology

authors： Marcou Q,Carmi-Levy I,Trichot C,Soumelis V,Mora T,Walczak AM

更新日期：2018-05-16 00:00:00

abstract：:Tissue factor (TF) is a transmembrane glycoprotein cofactor of activated blood coagulation factor VII (FVIIa) that is required for hemostatic thrombin generation at sites of blood vessel injury. Membrane-associated TF detected in circulating blood of healthy subjects, referred to as intravascular or circulating TF has...

journal_title：Physical biology

authors： Tormoen GW,Rugonyi S,Gruber A,McCarty OJ

更新日期：2011-12-01 00:00:00

abstract：:Bacteria such as Escherichia coli propel themselves by rotating a bundle of helical filaments, each driven by a rotary motor embedded in the cell membrane. Each filament is an assembly of thousands of copies of the protein flagellin which assumes two different states. We model the filament by an elastic network of rig...

journal_title：Physical biology

authors： Speier C,Vogel R,Stark H

更新日期：2011-08-01 00:00:00

abstract：:Epithelial-to-mesenchymal transition (EMT) is a fundamental developmental process wherein polarized epithelial cells lose their junctional architecture and apical-basal polarity to become motile mesenchymal cells, and there is emerging evidence for its role in propagating tumor dissemination. While many multifaceted n...

journal_title：Physical biology

authors： Antony J,Thiery JP,Huang RY

更新日期：2019-05-07 00:00:00

abstract：:We propose a three-dimensional mechanical model of embryonic tissue dynamics. Mechanically coupled adherent cells are represented as particles interconnected with elastic beams which can exert non-central forces and torques. Tissue plasticity is modeled by a stochastic process consisting of a connectivity change (addi...

journal_title：Physical biology

authors： Czirok A,Isai DG

更新日期：2014-12-15 00:00:00

abstract：:A series of simulations aimed at elucidating the self-assembly dynamics of spherical virus capsids is described. This little-understood phenomenon is a fascinating example of the complex processes that occur in the simplest of organisms. The fact that different viruses adopt similar structural forms is an indication o...

journal_title：Physical biology

authors： Rapaport DC

更新日期：2010-12-09 00:00:00

abstract：:Cell signaling is achieved predominantly by reversible phosphorylation-dephosphorylation reaction cascades. Up until now, circuits conferring adaptation have all required the presence of a cascade with some type of closed topology: negative-feedback loop with a buffering node, or incoherent feed-forward loop with a pr...

journal_title：Physical biology

authors： Srividhya J,Li Y,Pomerening JR

更新日期：2011-08-01 00:00:00

abstract：:The translocation of molecules across cellular membranes or through synthetic nanopores is strongly affected by thermal fluctuations. In this work we study how the dynamics of a polymer in a noisy environment changes when the translocation process is driven by an oscillating electric field. An improved version of the ...

journal_title：Physical biology

authors： Pizzolato N,Fiasconaro A,Adorno DP,Spagnolo B

更新日期：2010-08-04 00:00:00

abstract：:We model the motility of Dictyostelium cells in a systematic data-driven manner. We deduce a minimal dynamical model that reproduces the statistical features of experimental trajectories. These are trajectories of the centroid of the cell perimeter, which is more sensitive to pseudopod activity than the usual tracking...

journal_title：Physical biology

authors： Li L,Cox EC,Flyvbjerg H

更新日期：2011-08-01 00:00:00

abstract：:We investigate a novel approach for studying protein folding that has evolved from robotics motion planning techniques called probabilistic roadmap methods (PRMs). Our focus is to study issues related to the folding process, such as the formation of secondary and tertiary structures, assuming we know the native fold. ...

journal_title：Physical biology

authors： Thomas S,Song G,Amato NM

更新日期：2005-11-09 00:00:00

abstract：:'ENVIRONMENT' is a computational platform that has been developed in the last few years with the aim to simulate stochastically the dynamics and stability of chemically reacting protocellular systems. Here we present and describe some of its main features, showing how the stochastic kinetics approach can be applied to...

journal_title：Physical biology

authors： Mavelli F,Ruiz-Mirazo K

更新日期：2010-08-11 00:00:00

abstract：:Successful biological development via spatial regulation of cell differentiation relies on the action of multiple signaling molecules that are known as morphogens. It is now well-established that signaling molecules create non-uniform concentration profiles, morphogen gradients, that activate different genes, leading ...

journal_title：Physical biology

authors： Teimouri H,Kolomeisky AB

更新日期：2015-04-17 00:00:00

abstract：:Protein-protein interactions are central to biology and, in this 'post-genomic era', prediction of these interactions has become the goal of many computational efforts. Close inspection of even relatively simple biological regulatory circuitry reveals multiple levels of control of the contributing protein interactions...

journal_title：Physical biology

authors： Beckett D

更新日期：2005-06-01 00:00:00

abstract：:When motile cells come into contact with one another their motion is often considerably altered. In a process termed contact inhibition of locomotion (CIL) cells reshape and redirect their movement as a result of cell-cell contact. Here we describe a mathematical model that demonstrates that CIL alone is sufficient to...

journal_title：Physical biology

authors： Coburn L,Cerone L,Torney C,Couzin ID,Neufeld Z

更新日期：2013-08-01 00:00:00

abstract：:When the author arrived in Berkeley, in the mid 1970s, to study Biophysics he soon felt as if he was engaging himself in a somewhat marginal activity. Biology was then entering another of its cyclical periods of annotation that was to culminate with the human genome project. Two decades later, however, at the end of t...

journal_title：Physical biology

authors： Bustamante CJ

更新日期：2014-10-08 00:00:00

abstract：:The detection of gravity plays a fundamental role during the growth and evolution of plants. Although progress has been made in our understanding of the molecular, cellular and physical mechanisms involved in the gravity detection, a coherent scenario consistent with all the observations is still lacking. In this spec...

journal_title：Physical biology

authors： Pouliquen O,Forterre Y,Bérut A,Chauvet H,Bizet F,Legué V,Moulia B

更新日期：2017-05-23 00:00:00

abstract：:Modeling the spatiotemporal dynamics of biochemical reaction systems at single-molecule resolution has become feasible with the increase of computing power and is applied especially to cellular signal transduction. For an association reaction the two molecules have to be in contact. Hence, a physically faithful model ...

journal_title：Physical biology

authors： Klann M,Koeppl H

更新日期：2013-08-01 00:00:00

abstract：:Mucociliary clearance and cough are the two main natural mucus draining methods in the bronchial tree. If they are affected by a pathology, they can become insufficient or even ineffective, then therapeutic draining of mucus plays a critical role to keep mucus levels in the lungs acceptable. The manipulations of physi...

journal_title：Physical biology

authors： Mauroy B,Fausser C,Pelca D,Merckx J,Flaud P

更新日期：2011-10-01 00:00:00

abstract：:Traditionally animal groups have been characterized by the macroscopic patterns that they form. It is now recognised that such patterns convey limited information about the nature of the aggregation as a whole. Aggregate properties cannot be determined by passive observations alone; instead one must interact with them...

journal_title：Physical biology

authors： Reynolds AM

更新日期：2019-04-23 00:00:00

abstract：:Shelter-in-place and other confinement strategies implemented in the current COVID-19 pandemic have created stratified patterns of contacts between people: close contacts within households and more distant contacts between the households. The epidemic transmission dynamics is significantly modified as a consequence. W...

journal_title：Physical biology

authors： Huber G,Kamb M,Kawagoe K,Li LM,Veytsman B,Yllanes D,Zigmond D

更新日期：2020-10-21 00:00:00

abstract：:Based on the experimental evidence that translating ribosomes stabilize the mRNAs, we introduce and study a theoretical model for the dynamic shielding of mRNA by ribosomes. We present an improved fitting of published decay assay data in E. coli and show that only one third of the decay patterns are exponential. Our n...

journal_title：Physical biology

authors： Deneke C,Lipowsky R,Valleriani A

更新日期：2013-08-01 00:00:00

abstract：:Host-to-host variability with respect to interactions between microorganisms and multicellular hosts are commonly observed in infection and in homeostasis. However, the majority of mechanistic models used to analyze host-microorganism relationships, as well as most of the ecological theories proposed to explain coevol...

journal_title：Physical biology

authors： Mukherjee S,Weimer KE,Seok SC,Ray WC,Jayaprakash C,Vieland VJ,Swords WE,Das J

更新日期：2014-12-04 00:00:00

abstract：:In addition to serving as structural elements and as tracks for motor proteins, microtubules use chemical energy derived from the hydrolysis of GTP to generate forces when growing and shrinking. These forces are used to push or pull on organelles such as chromosomes and the mitotic spindle. If an array of microtubules...

journal_title：Physical biology

authors： Howard J

更新日期：2006-02-28 00:00:00

abstract：:The importance of the tumor microenvironment in cancer progression is undisputed, yet the significance of biophysical forces in the microenvironment remains poorly understood. Interstitial fluid flow is a nearly ubiquitous and physiologically relevant biophysical force that is elevated in tumors because of tumor-assoc...

journal_title：Physical biology

authors： Shieh AC,Swartz MA

更新日期：2011-02-01 00:00:00

abstract：:The important role of cation-chloride co-transporters in epilepsy is being supported by an increasing number of investigations. However, enormous complexity is involved since the action of these co-transporters has effects on the ionic homeostasis influencing directly the neuronal excitability and the tissue propensit...

journal_title：Physical biology

authors： Lopes MR,Santos LE,Rodrigues AM,Duarte MA,Infantosi AF,Scorza FA,Arida RM,Madureira AP,da Silveira GA,dos Santos IC,Cavalheiro EA,de Almeida AC

更新日期：2013-10-01 00:00:00

abstract：:We present a simple two-state model to understand the size-dependent endocytosis of nanoparticles. Using this model, we elucidate the relevant energy terms required to understand the size-dependent uptake mechanism and verify it by correctly predicting the behavior at large and small particle sizes. In the absence of ...

journal_title：Physical biology

authors： Chaudhuri A,Battaglia G,Golestanian R

更新日期：2011-08-01 00:00:00

abstract：:Motile biological cells in tissue often display the phenomenon of durotaxis, i.e. they tend to move towards stiffer parts of substrate tissue. The mechanism for this behavior is not completely understood. We consider simplified models for durotaxis based on the classic persistent random walker scheme. We show that eve...

journal_title：Physical biology

authors： Doering CR,Mao X,Sander LM

更新日期：2018-09-11 00:00:00

abstract：:Single-molecule manipulation has allowed the forced unfolding of multidomain proteins. Here we develop a theory that not only explains these experiments, but also points out a number of difficulties in their interpretation and makes suggestions for further experiments. Our theory is valid for essentially any molecule ...

journal_title：Physical biology

authors： Staple DB,Payne SH,Reddin AL,Kreuzer HJ

更新日期：2009-07-01 00:00:00