Thermal noise in aqueous quadrupole micro- and nano-traps

Recent simulations and experiments with aqueous quadrupole micro-traps have confirmed a possibility for control and localization of motion of a charged particle in a water environment, also predicting a possibility of further reduction of the trap size to tens of nano-meters for trapping charged bio-molecules and DNA segments. We study the random thermal noise due to Brownian motion in water which significantly influences the trapping of particles in an aqueous environment. We derive the exact, closed-form expressions for the thermal fluctuations of position and velocity of a trapped particle and thoroughly examine the properties of the rms for the fluctuations as functions of the system parameters and time. The instantaneous signal transferring mechanism between the velocity and position fluctuations could not be achieved in the previous phase-average approaches

Erratum: Dirichlet Forms and Dirichlet Operators for Infinite Particle Systems: Essential Self-adjointness

We reprove the essential self-adjointness of the Dirichlet operators of Dirchlet forms for infinite particle systems with superstable and sub-exponentially decreasing interactions.Comment: This is an erratum to the work appeared in J. Math. Phys. 39(12), 6509-6536 (1998

Ring hulls and applications

AbstractOur goal is to develop methods that enable one to select a class K of rings and then to describe all right essential overrings or all right rings of quotients of a given ring R which lie in K. Our major method of attack is to determine the existence and/or uniqueness of right ring hulls of R in K and to use these to characterize the right essential overrings of R which are in K. Some applications are: (1) a characterization of the right rings of quotients of the 2-by-2 upper triangular matrix ring over a PID which are either Baer or right extending; (2) a characterization of a continuous ring hull for a commutative ring whose singular ideal has finite uniform dimension; (3) a characterization of the right extending rings which have the 2-by-2 matrix ring over a given division ring for their maximal right ring of quotients; (4) a characterization of the intermediate right extending rings between the 2-by-2 upper triangular matrix ring and the 2-by-2 matrix ring over a large class of local right finitely Σ-extending rings; (5) a characterization of the classical right ring of quotients as a ring hull from a certain class of rings

Comments on "Entropy of 2D Black Holes from Counting Microstates"

In a recent letter, Cadoni and Mignemi proposed a formulation for the statistical computation of the 2D black holes entropy. We present a criticism about their formulation.Comment: 5 pages, Latex, no figure

Direct Assembly of Modified Proteins on Carbon Nanotubes in an Aqueous Solution

Carbon nanotubes (CNTs) have superior mechanical and electrical properties that have opened up many potential applications. However, poor dispersibility and solubility, due to the substantial van der Waals attraction between tubes, have prevented the use of CNTs in practical applications, especially biotechnology applications. Effective dispersion of CNTs into small bundles or individual tubes in solvents is crucial to ensure homogeneous properties and enable practical applications. In addition to dispersion of CNTs into a solvent, the selection of appropriate solvent, which is compatible with a desired matrix, is an important factor to improve the mechanical, thermal, optical, and electrical properties of CNT-based fibers and composites. In particular, dispersion of CNTs into an aqueous system has been a challenge due to the hydrophobic nature of CNTs. Here we show an effective method for dispersion of both single wall CNTs (SWCNTs) and few wall CNTs (FWCNTs) in an aqueous buffer solution. We also show an assembly of cationized Pt-cored ferritins on the well dispersed CNTs in an aqueous buffer solution