317 research outputs found
The Pavlov Department of Physiology: A Scientific History
Se sigue la aventura científica del Departamento de Fisiología Ivan Pavlov desde los trabajos pioneros de Pavlov y sus discípulos sobre la “salivación psíquica” hasta los tiempos de la Estación Biológica de Koltushi. Se describe el desarrollo del Departamento tras la muerte de Pavlov y se comentan las líneas de investigación de los actuales laboratorios (Neurobiología de las Funciones Integradoras del Cerebro, Psicofisiología de las Emociones y Corrección Neurodinámica de la Patología Psiconeurológica).The scientific adventure of the Ivan Pavlov Department of Physiology is traced from Pavlov’s and his students pioneer work on “psychic salivation” to the times of the Biological Station at Koltushi. The development of the Department after Pavlov’s death is described and the research trends of the three present laboratories (Neurobiology of Integrative Brain Functions, Psychophysiology of Emotions, and Neurodynamic Correction of Psycho Neurological Pathology) are discussed
Finding of the lesser flying squid (Todaropsis eblanae, oegopsida, ommastrephidae) from the Barents Sea
A specimen of the squid Todaropsis eblanae (Ball 1841) was caught in the Barents Sea by a pelagic trawl for the first time (71°13'N-36°38'E, 0-60-m trawling horizon, at a depth of 225 m). The maturing squid male caught had 29 spermatophores in spermatophoric sac, dorsal mande of 92 mm long, and body weight of 67.3 g. Obviously, this specimen has come here from the North Sea along the eastern branch of the Norwegian current and southern branch of the Nordcap current
First assessment of biomass and abundance of cephalopods Rossia palpebrosa and Gonatus fabricii in the Barents Sea
Copyright © Marine Biological Association of the United Kingdom 2016Studies on the quantitative distribution of cephalopods in the Arctic are limited, and almost completely absent for the Barents Sea. It is known that the most abundant cephalopods in the Arctic are Rossia palpebrosa and Gonatus fabricii. Their biomass and abundance have been assessed for the first time in the Barents Sea and adjacent waters. The maximum biomass of R. palpebrosa in the Barents Sea was 6.216–6.454 thousand tonnes with an abundance of 521.5 million specimens. Increased densities of biomass were annually registered in the north-eastern parts of the Barents Sea. The maximum biomass of G. fabricii in the Barents Sea was 24.797 thousand tonnes with an abundance of 1.705 billion specimens. The areas with increased density of biomass (higher than 100 kg km−2) and abundance (more than 10,000 specimens km−2) were concentrated in deep-water troughs in the marginal parts of the Barents Sea and in adjacent deep-water areas. The biomass and abundance of R. palpebrosa and G. fabricii in the Barents Sea were much lower than those of major taxa of invertebrates and fish and than those of cephalopods in other parts of the World Ocean. It has been suggested that the importance of cephalopods in the Arctic ecosystems, at least in terms of quantitative distribution, could be somewhat lower than in the Antarctic or the tropics. Despite the impact of ongoing warming of the Arctic on the distribution of cephalopods being described repeatedly already, no impact of the current year's climate on the studied species was found. The only exception was the abundance of R. palpebrosa, which correlated with the current year's climate conditions
On the superfluidity of classical liquid in nanotubes
In 2001, the author proposed the ultra second quantization method. The ultra
second quantization of the Schr\"odinger equation, as well as its ordinary
second quantization, is a representation of the N-particle Schr\"odinger
equation, and this means that basically the ultra second quantization of the
equation is the same as the original N-particle equation: they coincide in
3N-dimensional space.
We consider a short action pairwise potential V(x_i -x_j). This means that as
the number of particles tends to infinity, , interaction is
possible for only a finite number of particles. Therefore, the potential
depends on N in the following way: . If V(y) is finite
with support , then as the support engulfs a finite
number of particles, and this number does not depend on N.
As a result, it turns out that the superfluidity occurs for velocities less
than , where
is the critical Landau velocity and R is the radius of
the nanotube.Comment: Latex, 20p. The text is presented for the International Workshop
"Idempotent and tropical mathematics and problems of mathematical physics",
Independent University of Moscow, Moscow, August 25--30, 2007 and to be
published in the Russian Journal of Mathematical Physics, 2007, vol. 15, #
Aggregate ranking of the world's leading universities
The paper presents a methodology for calculating the aggregate global university ranking (Aggregated Global University Ranking, or AGUR), which consists of an automated presentation of the comparable lists of names for different universities from particular global university rankings and a simple procedure of aggregating particular global university rankingsyesBelgorod State Universit
Changes in distribution and range structure of Arctic cephalopods due to climatic changes of the last decades
The warming of Arctic waters over the last decades has been confirmed by the results of numerous studies. New data on distribution of cephalopods in the Arctic were obtained from the research cruises of PINRO (Russia) and IMR (Norway) during 2006-2011. Teuthowenia megalops and Todaropsis eblanae were found in the Arctic for the first time, at distances of more than 1000 km and 2500 km outside of their ranges, respectively. The demersal species T. eblanae inhabiting the lower shelf and upper continental slope has presumably spread into the Barents Sea by the eastern branch of the Norwegian Current, and further by the southern branch of the North Cape coastal current, as far as the Murman shelf. The bathypelagic species T. megalops is carried to the Arctic evidently by the deep-water warm Atlantic Currents. The new spreading areas of both species are obviously the non-reproductive zones of their ranges. Foraging shoals of Todarodes sagitatus were recorded in the Arctic in 2010 for the first time in the last 25 years, which can be related to not only the warming of Arctic waters, but also the fluctuation of Todarodes levels in the main part of the range in the Northern Atlantic. The native Arctic species Gonatus fabricii has expanded its range to the eastern part of the Barents Sea and to the adjacent part of the Kara Sea. In these areas of Arctic waters, warming is particularly noticeable and the ongoing climatic changes are leading to boreal cephalopods spreading into the Polar Basin. This may impact species relations in vulnerable Arctic ecosystems. © 2013 Copyright Taylor and Francis Group, LLC
Structure of the reproductive system and hectocotylus in males of lesser flying squid Todaropsis eblanae (Cephalopoda: Ommastrephidae)
This paper introduces new data on Todaropsis eblanae morphology, morphometry and functional aspects of the male reproductive system and hectocotylus. Spermatophores differ in specimens from the Atlantic Ocean (average length, 18.28 ± 1.45 mm, 15.63 ± 0.8% of mantle length; weight, 2.0-12.0 mg) and the Indian Ocean (average length, 24.8 ± 2.85 mm, 16.9 ± 2.1% of mantle length; weight, 35.0-39.6 mg) (t = 3.14; p 001 for relative sizes). An additional important distinctive trait is the form of connection of the cement body with the ejaculatory tube. In recent years, T. eblanae has been regularly caught in the Barents Sea, meaning its range has extended to subarctic waters. The morphology and morphometry of the spermatophoric complex of organs did not vary in investigated parts of its range. Hectocotylus patterns and some important spermatophore traits distinguish Todaropsis from other Ommastrephidae. © 2012 Copyright Taylor and Francis Group, LLC
The northernmost record of Sepietta oweniana (Cephalopoda: Sepiolidae) and omments on boreo-subtropical cephalopod species occurrence in the arctic
© Marine Biological Association of the United Kingdom, 2014. The first observation of the common bobtail squid Sepietta oweniana has been made in the Barents Sea (Tromsø Bank; 70°54′ N 19°46.8′E). It is the northernmost area of this species distribution. No changes were found in the reproductive system structure. But the food spectrum was changed, particularly, juvenile fish of the Lotidae family was found. The bobtail squid of the Sepiolinae subfamily have never been recorded as fish eaters previously. The expansion of boreosubtropical species of cephalopods into the Arctic during the last decade can be divided into two groups: (1) a foraging migration happening relatively regularly; and (2) a range expansion due to the ongoing Arctic warming. The case of S. oweniana obviously belongs to the second group
Сравнение расчетных и измеренных значений мощности кермы в воздухе над почвой, загрязненной 137Cs
In 2010, a study was conducted to determine the air gamma dose rate from 137Cs deposited in soil. The gamma dose rate measurements and soil sampling were performed at 30 reference plots from the south-west districts of the Bryansk region (Russia) that had been heavily contaminated as a result of the Chernobyl accident. The 137Cs inventory in the top 20 cm of soil ranged from 260 kBq m–2 to 2800 kBq m–2. Vertical distributions of 137Cs in soil cores (6 samples per a plot) were determined after their sectioning into ten horizontal layers of 2 cm thickness. The vertical distributions of 137Cs in soil were employed to calculate air kerma rates, K, using two independent methods proposed by Saito and Jacob [Radiat. Prot. Dosimetry, 1995, Vol. 58, P. 29–45] and Golikov et al. [Contaminated Forests– Recent Developments in Risk Identification and Future Perspective. Kluwer Academic Publishers, 1999. – P. 333–341]. A very good coincidence between the methods was observed (Spearman’s rank coefficient of correlation = 0.952; P<0.01); on average, a difference between the kerma rates calculated with two methods did not exceed 3%. The calculated air kerma rates agreed with the measured dose rates in air very well (Spearman’s coefficient of correlation = 0.952; P<0.01). For large grassland plots (n=19), the measured dose rates were on average 6% less than the calculated kerma rates. The tested methods for calculating the air dose rate from 137Cs in soil can be recommended for practical studies in radiology and radioecology. В 2010 г. было проведено исследование, целью которого являлось сравнение расчетных и измеренных значений мощности кермы гамма-излучения в воздухе от радионуклида 137Cs, залегающего в почве. Измерения мощности кермы в воздухе, K , и отбор проб почвы были выполнены на 30 референтных участках, находящихся в юго-западных районах Брянской области России. Эти участки почвы были сильно загрязнены в результате Чернобыльской аварии. Запас 137Cs в верхних 20 см почвы на этих участках колебался от 260 кБк/м2 до 2800 кБк/м2. Исследовано вертикальное распределение активности 137Cs в почве, которое было использовано для расчета мощности кермы в воздухе, K , с применением двух независимых методов, предложенных Saito and Jacob [Radiat. Prot. Dosimetry, 1995, Vol. 58, P. 29–45] и Golikov et al. [Contaminated Forests– Recent Developments in Risk Identification and Future Perspective. Kluwer Academic Publishers, 1999. – P. 333–341]. В среднем расхождение между результатами расчетов двумя методами составило 3% (коэффициент корреляции Спирмена=0,952; P<0,01). Для больших открытых площадок (n=19) обнаружено хорошее согласие между результатами расчетов и результатами измерений мощности кермы в воздухе (коэффициент корреляции Спирмена=0,935; P<0,01). Измеренная мощность кермы в воздухе оказалась в среднем на 6% меньше, чем рассчитанная. Обе расчетные модели могут быть использованы в практических радиоэкологических и радиационно-гигиенических работах для оценки мощности кермы гамма-излучения в воздухе от 137Cs, залегающего в почве
Large-scale Samples Irradiation Facility at the IBR-2 Reactor in Dubna
The irradiation facility at the beam line no.3 of the IBR-2 reactor of the Frank Laboratory for Neutron Physics is described. The facility is aimed at irradiation studies of various objects with area up to 800 cm both at cryogenic and ambient temperatures. The energy spectra of neutrons are reconstructed by the method of threshold detector activation. The neutron fluence and dose rates are measured by means of alanine and thermoluminescent dosimeters. The boron carbide and lead filters or converter provide beams of different ratio of doses induced by neutrons and photons. For the lead filter, the flux of fast neutrons with energy more than 0.1 MeV is \fln and the neutron dose is about 96\% of the total radiation dose. For the converter, the dose rate is 500 Gy h which is about 85\% of the total dose. The radiation hardness tests of GaAs electronics and materials for the ATLAS detector to be put into operation at the Large Hadron Collider (LHC) have been performed successfully at this facility
- …