Review of investigation on the feeding of the European grayling [Translation from: Flora Slodkowodna Polski. Tom 2. Cyanophyta, Glaucophyta (ed. K. Starmach) p350-352. Warsaw, Polska Academia Nauk, 1966]

The composition of the food of the European grayling and the character of its feeding has been studied fully enough, but this knowledge is scattered in the literature and often contradictory. rare exceptions, analysis of the results of different investigations. Therefore the proposed short outline of the history of the study of the problem with a description of the basic data on the feeding of the grayling in different geographical areas is presented as expedient and opportune, primarily in relation to the determination of immediate problems and the trend of research

On Wilson Criterion

U(1) gauge theory with the Villain action on a cubic lattice approximation of three- and four-dimensional torus is considered. The naturally chosen correlation functions converge to the correlation functions of the R-gauge electrodynamics on three- and four-dimensional torus as the lattice spacing approaches zero only for the special scaling. This special scaling depends on a choice of a correlation function system. Another scalings give the degenerate continuum limits. The Wilson criterion for the confinement is ambiguous. The asymptotics of the smeared Wilson loop integral for the large loop perimeters is defined by the density of the loop smearing over a torus which is transversal to the loop plane. When the initial torus radius tends to infinity the correlation functions converge to the correlation functions of the R-gauge Euclidean electrodynamics.Comment: latex, 6 page

Partial Supersymmetry Breaking from Five Dimensions

Theories of partial supersymmetry breaking N=2 -> N=1 in four dimensions are derived by coupling the N=2 massless gravitino multiplet to N=2 supergravity in five dimensions and performing a generalized dimensional reduction on S^1/Z_2 with the Scherk-Schwarz mechanism. These theories agree with results that were previously derived from four dimensions.Comment: 15 pages, Latex; introduction slightly changed, one reference adde

Optical properties of tissue measured using terahertz pulsed imaging.

The first demonstrations of terahertz imaging in biomedicine were made several years ago, but few data are available on the optical properties of human tissue at terahertz frequencies. A catalogue of these properties has been established to estimate variability and determine the practicality of proposed medical applications in terms of penetration depth, image contrast and reflection at boundaries. A pulsed terahertz imaging system with a useful bandwidth 0.5-2.5 THz was used. Local ethical committee approval was obtained. Transmission measurements were made through tissue slices of thickness 0.08 to 1 mm, including tooth enamel and dentine, cortical bone, skin, adipose tissue and striated muscle. The mean and standard deviation for refractive index and linear attenuation coefficient, both broadband and as a function of frequency, were calculated. The measurements were used in simple models of the transmission, reflection and propagation of terahertz radiation in potential medical applications. Refractive indices ranged from 1.5 ± 0.5 for adipose tissue to 3.06 ± 0.09 for tooth enamel. Significant differences (P<0.05) were found between the broadband refractive indices of a number of tissues. Terahertz radiation is strongly absorbed in tissue so reflection imaging, which has lower penetration requirements than transmission, shows promise for dental or dermatological applications

Chemical composition of Iraq water resources (abbreviated translation) [Translation from: Vodnye Resursy 1975(4,) 173-185]

This abbreviated translation summarises the chemical composition of Iraq water resources. Among the described water bodies are the River Euphrates, Shatt al Arab River and a number of standing waters

Proton polarizability contribution to the hyperfine splitting in muonic hydrogen

The contribution of the proton polarizability to the ground state hyperfine splitting in muonic hydrogen is evaluated on the basis of modern experimental and theoretical results on the proton polarized structure functions. The value of this correction is equal to 4.6(8)\cdot 10^{-4} times the Fermi splitting E_F.Comment: 10 pages (revtex), 5 figure

Subwave spikes of the orbital angular momentum of the vortex-beams in a uniaxial crystal

We have theoretically predicted the gigantic spikes of the orbital angular momentum caused by the conversion processes of the centered optical vortex in the circularly polarized components of the elliptic vortex beam propagating perpendicular to the crystal optical axis. We have experimentally observed the conversion process inside the subwave deviations of the crystal length. We have found that the total orbital angular momentum of the wave beam is conserved.Comment: 3 pages, 3 figure

Investigation of reflecting discharge with the sectioned metal-hydride hollow cathode

In this paper the investigations of Penning discharge with the sectioned hollow cathode in hydrogen environment were carried out. As constructional elements of the hollow cathode the Zr50V50 alloy, which is able to absorb hydrogen reversibly was used. Using metal-hydride cathode was shown to allow to reduce the voltage of hollow cathode mode exciting. The possibility of hollow cathode mode operating by means of variation of potentials on its sections was investigated.У роботі проведені дослідження розряду Пенінга в середовищі водню із секціонованим порожнистим катодом. Як конструкційні елементи порожнистого катода використовувався сплав Zr50V50, здатний до оборотного поглинання водню. Показано, що застосування металогидрідного порожнистого катода дозволяє зменшити напругу збудження ефекту порожнистого катода. Досліджено можливість керування режимом порожнистого катода шляхом варіювання потенціалами на його секціях.В работе проведены исследования разряда Пеннинга в среде водорода с секционированным полым катодом. В качестве конструкционных элементов полого катода использовался сплав Zr50V50, способный к обратимому поглощению водорода. Показано, что применение металлогидридного полого катода позволяет уменьшить напряжение возбуждения эффекта полого катода. Исследована возможность управления режимом полого катода путем варьирования потенциалами на его секциях