Instant gene bank method adapted for cloning mutant benomyl-resistance allele in replicative vector in Aspergillus nidulans

The instant gene bank method for gene cloning by mutant complementation in Aspergillus nidulans uses ligation in vivo of donor DNA and an autonomously replicating plasmid to obviate the necessity for an intermediate bacterial host (Gems et al. 1994 Mol. Gen. Genet. 242:467-471). Its applicability was demonstrated by cloning the TrpC gene from Penicillium canescens. Here we report a modification of the method for cloning a mutant allele promoting benomyl resistance from Penicillium canescens, with the final aim of using it as a transformation selectable marker

High frequency limit of the Transport Cross Section and boundedness of the Total Cross Section in scattering by an obstacle with impedance boundary conditions

The scalar scattering of the plane wave by a strictly convex obstacle with impedance boundary conditions is considered. The uniform boundedness of the Total Cross Section for all values of frequencies is proved. The high frequency limit of the Transport Cross Section is founded and presented as a classical functional of the variational theory

Aspergillus nidulans pyrE and pyrF

Sequencing of a gene cloned by complementation of a pyr mutant in Glasgow strain G190 shows this mutant to be pyrE, encoding dihydroorotate dehydrogenase. This discovery necessitates a revision of the genetic map derived from crosses with this strain

Spectral properties of the Dirichlet-to-Neumann operator for exterior Helmholtz problem and its applications to scattering theory

We prove that the Dirichlet-to-Neumann operator (DtN) has no spectrum in the lower half of the complex plane. We find several application of this fact in scattering by obstacles with impedance boundary conditions. In particular, we find an upper bound for the gradient of the scattering amplitude and for the total cross section. We justify numerical approximations by providing bounds on difference between theoretical and approximated solutions without using any a priory unknown constants

Invisibility in billiards

The question of invisibility for bodies with mirror surface is studied in the framework of geometrical optics. We construct bodies that are invisible/have zero resistance in two mutually orthogonal directions, and prove that there do not exist bodies which are invisible/have zero resistance in all possible directions of incidence

Comparison of mechanical and tribotechnical properties of UHMWPE reinforced with basalt fibers and particles

Mechanical and tribotechnical properties of UHMWPE composites reinforced with basalt fibers and particles under dry sliding friction and abrasion were investigated. It is shown that adding of the basalt particles provides higher wear resistance under the dry sliding friction while at abrasion filling by the basalt fibers is more efficient since the wear resistance of the reinforced UHMWPE composites is by 3.7 times higher in contrast with the neat polymer. Wear mechanisms of the polymeric UHMWPE composites under various types of wear are discussed

Influence of the main geometrical parameters on the design and performance of mixed inflow turbines

The blade shape is of great interest to hybrid turbine designers, due to its significant and direct impact on turbine performance. The inlet and outlet diameters of the vane affect the size of the rotor, which is limited because of the small space available in internal combustion engines. The effect of the ratio of the average inlet diameter and the average exducer inlet diameter on the performance of a mixed inlet turbine will be the focus of this study, which consists of two cases included herein for the purpose of illustrating the means of improving rotor performances and controlling the flow mass rate. In the first case, we achieved this by changing the average diameter of the exducer inlet, while, in the second one, we achieved this by changing the average inlet diameter. Additionally, the angles of the inlet and outlet blades were recalculated to preserve the same blade profile and to eliminate the effect of curvilinearity. It was noted that the shape of the blade was very sensitive to changes in the ratio of the investigated diameters, and—in both cases—interesting results were obtained. First, an increase in output work and in total static isentropic efficiency by 2.16% and 2.15%, respectively, was generated, with a saving of 3.52% of the used mass flow and a lighter rotor compared to one that used to take up the same space by using fixed average inlet diameter blades. In the second case, there was an increase in the output work by 3.31%, and in the total static isentropic efficiency by 3.34%, but the rotor became heavier and required an increase in the mass flow used. Since inter-blade flows are very complex, three-dimensional and viscous—featuring various types of secondary and eddy flows—the CFX.15-CFD code was used in all models to solve the averaged Navier–Stokes equations.The authors are grateful to FCT—Fundação para a Ciência e Tecnologia (Portugal)—who partially financially supported this work through the RD Units Project Scope: UIDP/04077/2020 and UIDB/04077/2020

Resonance regimes of scattering by small bodies with impedance boundary conditions

The paper concerns scattering of plane waves by a bounded obstacle with complex valued impedance boundary conditions. We study the spectrum of the Neumann-to-Dirichlet operator for small wave numbers and long wave asymptotic behavior of the solutions of the scattering problem. The study includes the case when $k=0$ is an eigenvalue or a resonance. The transformation from the impedance to the Dirichlet boundary condition as impedance grows is described. A relation between poles and zeroes of the scattering matrix in the non-self adjoint case is established. The results are applied to a problem of scattering by an obstacle with a springy coating. The paper describes the dependence of the impedance on the properties of the material, that is on forces due to the deviation of the boundary of the obstacle from the equilibrium position

Application of Elements of Ergotherapy in Refusal Work with Persons who Have Been Suspected

Дослідження спрямоване на виявлення ступеню відновлення втрачених функцій та навиків самообслуговування у хворих з гострим порушенням мозкового кровообігу під впливом занять з ерготерапії.The research is directed to detect a degree recovery of lost functions and self-care skills in patients with acute violation of cerebral circulation under the influence of occupations on ergotherapy