TeV neutrinos from microquasars in compact massive binaries

We consider a compact binary system in which a Wolf-Rayet star supplies matter onto a stellar mass black hole or a neutron star. This matter forms an accretion disk which ejects a jet as observed in Galactic microquasars. A part of the jet kinetic energy, typically 10%, can be transfered to relativistic nuclei. These nuclei lose nucleons as a result of photo-disintegration process in collisions with thermal photons from the accretion disk and the massive star. Due to the head on photon-nucleus collisions most of neutrons released from nuclei move towards the surface of the accretion disk and/or the massive star producing neutrinos in collisions with the matter. We calculate the spectra of muon neutrinos and expected neutrino event rates in a 1 km^2 neutrino detector of the IceCube type from a microquasar inside our Galaxy applying, as an example, the parameters of the Cyg X-3 binary system, provided that nuclei are accelerated to the Lorentz factors above 10^6 with the power law spectrum with an index close to 2.Comment: 13 pages, 2 figures, ApJ, accepte

TeV neutrinos from accreting X-ray pulsars

Pulsars inside binary systems can accrete matter that arrives up to the pulsar surface provided that its period is long enough. During the accretion process, matter has to be accelerated to the rotational velocity of the pulsar magnetosphere at the distance where the balance between the pressure of matter and the magnetic field is achieved. At this distance, a very turbulent and magnetized region is formed in which hadrons can be accelerated to relativistic energies. These hadrons can interact with the very strong radiation field coming from the hot polar cap on the neutron star surface created by the in-falling matter. We calculate the neutrino event rates produced in an km$^2$ detector that can be expected from accreting millisecond and classical X-ray pulsars at a typical distance within our own Galaxy.Comment: 5 pages, accepted to Physical Review

The Effects of Cocaine on Different Redox Forms of Cysteine and Homocysteine, and on Labile, Reduced Sulfur in the Rat Plasma Following Active versus Passive Drug Injections

Received: 28 November 2012 / Revised: 19 April 2013 / Accepted: 6 May 2013 / Published online: 16 May 2013 The Author(s) 2013. This article is published with open access at Springerlink.comThe aim of the present studies was to evaluate cocaine-induced changes in the concentrations of different redox forms of cysteine (Cys) and homocysteine (Hcy), and products of anaerobic Cys metabolism, i.e., labile, reduced sulfur (LS) in the rat plasma. The above-mentioned parameters were determined after i.p. acute and subchronic cocaine treatment as well as following i.v. cocaine self-administration using the yoked procedure. Additionally, Cys, Hcy, and LS levels were measured during the 10-day extinction training in rats that underwent i.v. cocaine administration. Acute i.p. cocaine treatment increased the total and protein-bound Hcy contents, decreased LS, and did not change the concentrations of Cys fractions in the rat plasma. In turn, subchronic i.p. cocaine administration significantly increased free Hcy and lowered the total and protein-bound Cys concentrations while LS level was unchanged. Cocaine self-administration enhanced the total and protein-bound Hcy levels, decreased LS content, and did not affect the Cys fractions. On the other hand, yoked cocaine infusions did not alter the concentration of Hcy fractions while decreased the total and protein-bound Cys and LS content. This extinction training resulted in the lack of changes in the examined parameters in rats with a history of cocaine self-administration while in the yoked cocaine group an increase in the plasma free Cys fraction and LS was seen. Our results demonstrate for the first time that cocaine does evoke significant changes in homeostasis of thiol amino acids Cys and Hcy, and in some products of anaerobic Cys metabolism, which are dependent on the way of cocaine administration

Exploiting structure similarity in refinement: automated NCS and target-structure restraints in BUSTER

Local structural similarity restraints (LSSR) provide a novel method for exploiting NCS or structural similarity to an external target structure. Two examples are given where BUSTER re-refinement of PDB entries with LSSR produces marked improvements, enabling further structural features to be modelled

Some physical properties of soil and yielding of crops grown with different forms of mulching and tillage

Celem badań było określenie wpływu stosowania zróżnicowanej uprawy roli i pożniwnego zagospodarowania słomy na niektóre właściwości fizyczne gleby i plonowanie roślin. Przy umiarkowanym niedoborze opadów, niezależnie od gospodarki słomą, istotnie niższe plony wydawały rośliny uprawiane systemem zerowym. W takich samych warunkach pogodowych, niezależnie od wariantów uprawowych, najniższe plony powodowało usuwanie słomy i nie stosowanie międzyplonu. W warunkach silnego niedoboru opadów poziom plonów był niski i na zmianę tego efektu nie miał znaczącego wpływu żaden z testowanych wariantów doświadczenia.The research aimed at assessing the influence of differentiated tillage and post-harvest straw management on some physical properties of soil and yielding of crop. The yielding of crops was differentiated; under moderate deficit of precipitation, irrespective of straw management, significantly lower yields were obtained of crops grown with zero system. Under similar weather conditions, irrespective of tillage system, the lowest yields were obtained when straw had been removed and no intercrop grown. Under strong deficiency of precipitation the yields were very low, that effect having been not changed significantly by any of the experimental variants tested

Combined heat and power systems in liquefied natural gas (LNG) regasification processes

Adaptation of liquefied natural gas (LNG) to the quality requirements for natural gas transportation pipeline system is a high energy intensive process. The energy for this process can be obtained include from waste heat in the industry processes, steam power blocks or sea water in LNG unloading terminal. Another way of obtaining the heat is burning of gas or other fuels. A large temperature difference between the heat sources in each of these cases, and the low temperature of LNG can be used to control of the pumping engine operation, it can pro vi de optimization and reduction of the costs. Liquefied natural gas (LNG) can be used as a source of cold to the increasing power of the cogeneration process. The article examines some practical cogeneration solutions (combined heat and called power - CHP), which can improve the efficiency of the process of regasification of LNG