Sequencing of real-world samples using a microfabricated hybrid device having unconstrained straight separation channels

We describe a microfabricated hybrid device that consists of a microfabricated chip containing multiple twin-T injectors attached to an array of capillaries that serve as the separation channels. A new fabrication process was employed to create two differently sized round channels in a chip. Twin-T injectors were formed by the smaller round channels that match the bore of the separation capillaries and separation capillaries were incorporated to the injectors through the larger round channels that match the outer diameter of the capillaries. This allows for a minimum dead volume and provides a robust chip/capillary interface. This hybrid design takes full advantage, such as sample stacking and purification and uniform signal intensity profile, of the unique chip injection scheme for DNA sequencing while employing long straight capillaries for the separations. In essence, the separation channel length is optimized for both speed and resolution since it is unconstrained by chip size. To demonstrate the reliability and practicality of this hybrid device, we sequenced over 1000 real-world samples from Human Chromosome 5 and Ciona intestinalis, prepared at Joint Genome Institute. We achieved average Phred20 read of 675 bases in about 70 min with a success rate of 91%. For the similar type of samples on MegaBACE 1000, the average Phred20 read is about 550-600 bases in 120 min separation time with a success rate of about 80-90%.     

Mathematical modeling of sedimentation of a rarefied cloud of particles

In the present paper a mathematical model of sedimentation of a rarefied cloud of particles with account of the feedback effect of particles on the fluid is suggested. The calculations have shown that this effect changes significantly the pattern of particle motion. The results of model calculations agree fairly well with the experimental data on the sedimentation of coal dust particles in a settler. Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 109–113, March, 1999.     

Second-Order Impedance Spectroscopy of an Electroreduction Reaction with Allowance for the Frumkin Correction

A theory of second-order impedance spectroscopy is developed. The theory is good for analyzing an electroreduction reaction in surface-inactive supporting electrolytes with allowance made for the structure of the electrical double layer (the Frumkin correction). According to the theory, a measured second-order impedance contains, as a factor, an effective charge transfer coefficient. The latter's dependence on potential has a minimum connected with the diffuseness of the electrical double layer. The theoretical notions are experimentally confirmed on the basis of a real system.     

Promising lines of investigations in the realms of laboratory astrophysics with the aid of powerful lasers

The results of work on choosing and substantiating promising lines of research in the realms of laboratory astrophysics with the aid of powerful lasers are presented. These lines of research are determined by the possibility of simulating, under laboratory conditions, problematic processes of presentday astrophysics, such as (i) the generation and evolution of electromagnetic fields in cosmic space and the role of magnetic fields there at various spatial scales; (ii) the mechanisms of formation and evolution of cosmic gamma-ray bursts and relativistic jets; (iii) plasma instabilities in cosmic space and astrophysical objects, plasma jets, and shock waves; (iv) supernova explosions and mechanisms of the explosion of supernovae featuring a collapsing core; (v) nuclear processes in astrophysical objects; (vi) cosmic rays and mechanisms of their production and acceleration to high energies; and (vii) astrophysical sources of x-ray radiation. It is shown that the use of existing powerful lasers characterized by an intensity in the range of 10¹⁸–10²² W/cm² and a pulse duration of 0.1 to 1 ps and high-energy lasers characterized by an energy in excess of 1 kJ and a pulse duration of 1 to 10 ns makes it possible to perform investigations in laboratory astrophysics along all of the chosen promising lines. The results obtained by experimentally investigating laser plasma with the aid of the laser facility created at Central Research Institute of Machine Building (TsNIIMash) and characterized by a power level of 10 TW demonstrate the potential of such facilities for performing a number of experiments in the realms of laboratory astrophysics.     

Combined measurement of double-layer and kinetic parameters of electrochemical systems using a potentiodynamic method under maximum fast response

A potentiodynamic method is proposed for combined measurement of double-layer and kinetic parameters using one pulse of semitrapezoidal form. This method provides the maximum fast measurement under criticial damping. The values of the critical damping mode characteristics are calculated for the limiting values of the parameters of potentiostats and cells. The system is studied by the root locus method.     

关于连通图最长圈的一个结果

设C是k-连通图G（2≤k≤6）的一个最长圈.H是G-C的一个分支.[5]中证明,若L（H）≥k-2,则｜C｜≥kδ-k（k-2）,这里L（H）表示H中最长路的长度,δ表示G的最小度.本文在H满足特定的条件时,对于k∈{3,4,5}改进了上述｜C｜的度下界.