Persistent organic pollutants (PCBs and OCP) in air and soil from Ulaanbaatar and the Lake Hovsgol region, Mongolia

The investigations of POPs in soil and air in three urban and rural sites of the Mongolia are presented. The POPs distribution in air repeats the POPs distribution in soil on the area investigated. The POPs levels in soil and air are lower than maximum permissible concentrations (MPC) and preliminary permissible concentrations (PPC) of PCBs and OCP accepted in Russia. POPs levels in Mongolian soil obtained in the investigation are comparable with those from background areas of the world. POPs levels in Mongolian air are in the frame of concentrations found in the world. The PCB homological pattern in soil near electric power station in Ulaanbaatar is close to homological pattern in PCB technical mixture (Sovol or Arochlor 1254). The homological patterns in soil from other sites changed due to the redistribution of PCB congeners in the environment. The ratio of DDT and its metabolites indicates fresh entrance of DDT in the environment of Mongolia due to the atmospheric transboundary transport from countries using DDT (China, India) or from local agricultural sources. Hazard indexes in result from human exposure with POPs in soil and air are lower by 2-4 orders than 1 that denotes the possible default of disturbances in target organ and system. CR under the same scenario corresponds to the first diapason that is taken by population as negligible risk, not differ from usual everyday risks. Such risks don’t require additional measures for the reducing of risks and their levels are a subject of periodical control. The necessity of additional investigation of POPs distribution and the fate in Mongolian environment is indicated.DOI: http://dx.doi.org/10.5564/mjc.v12i0.176 Mongolian Journal of Chemistry Vol.12 2011: 69-7

Closest horizons of Hsp70 engagement to manage neurodegeneration.

This is the final version. Available on open access from Frontiers Media via the DOI in this record. Our review seeks to elucidate the current state-of-the-art in studies of 70-kilodalton-weighed heat shock proteins (Hsp70) in neurodegenerative diseases (NDs). The family has already been shown to play a crucial role in pathological aggregation for a wide spectrum of brain pathologies. However, a slender boundary between a big body of fundamental data and its implementation has only recently been crossed. Currently, we are witnessing an anticipated advancement in the domain with dozens of studies published every month. In this review, we briefly summarize scattered results regarding the role of Hsp70 in the most common NDs including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). We also bridge translational studies and clinical trials to portray the output for medical practice. Available options to regulate Hsp70 activity in NDs are outlined, too.Russian Science Foundatio

The dependence of dijet production on photon virtuality in ep collisions at HERA

The dependence of dijet production on the virtuality of the exchanged photon, Q^2, has been studied by measuring dijet cross sections in the range 0 < Q^2 < 2000 GeV^2 with the ZEUS detector at HERA using an integrated luminosity of 38.6 pb^-1. Dijet cross sections were measured for jets with transverse energy E_T^jet > 7.5 and 6.5 GeV and pseudorapidities in the photon-proton centre-of-mass frame in the range -3 < eta^jet <0. The variable xg^obs, a measure of the photon momentum entering the hard process, was used to enhance the sensitivity of the measurement to the photon structure. The Q^2 dependence of the ratio of low- to high-xg^obs events was measured. Next-to-leading-order QCD predictions were found to generally underestimate the low-xg^obs contribution relative to that at high xg^obs. Monte Carlo models based on leading-logarithmic parton-showers, using a partonic structure for the photon which falls smoothly with increasing Q^2, provide a qualitative description of the data.Comment: 35 pages, 6 eps figures, submitted to Eur.Phys.J.

Beauty photoproduction measured using decays into muons in dijet events in ep collisions at s\sqrt{s}=318 GeV

The photoproduction of beauty quarks in events with two jets and a muon has been measured with the ZEUS detector at HERA using an integrated luminosity of 110 pb$^{- 1}$. The fraction of jets containing b quarks was extracted from the transverse momentum distribution of the muon relative to the closest jet. Differential cross sections for beauty production as a function of the transverse momentum and pseudorapidity of the muon, of the associated jet and of $x_{\gamma}^{jets}$, the fraction of the photon's momentum participating in the hard process, are compared with MC models and QCD predictions made at next-to-leading order. The latter give a good description of the data.Comment: 32 pages, 6 tables, 7 figures Table 6 and Figure 7 revised September 200

Search for a narrow charmed baryonic state decaying to D^*+/- p^-/+ in ep collisions at HERA

A resonance search has been made in the D^*+/- p^-/+ invariant-mass spectrum with the ZEUS detector at HERA using an integrated luminosity of 126 pb^-1. The decay channels D^*+ -> D^0 pi^+_s -> (K^- pi^+) pi^+_s and D^*+ -> D^0 pi^+_s -> (K^- pi^+ pi^+ pi^-) pi^+_s (and the corresponding antiparticle decays) were used to identify D^*+/- mesons. No resonance structure was observed in the D^*+/- p^-/+ mass spectrum from more than 60000 reconstructed D^*+/- mesons. The results are not compatible with a report of the H1 Collaboration of a charmed pentaquark, Theta^0_c.Comment: 22 pages, 7 figures, 1 table; minor text revisions; 2 references adde

Angular and Current-Target Correlations in Deep Inelastic Scattering at HERA

Correlations between charged particles in deep inelastic ep scattering have been studied in the Breit frame with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb-1. Short-range correlations are analysed in terms of the angular separation between current-region particles within a cone centred around the virtual photon axis. Long-range correlations between the current and target regions have also been measured. The data support predictions for the scaling behaviour of the angular correlations at high Q2 and for anti-correlations between the current and target regions over a large range in Q2 and in the Bjorken scaling variable x. Analytic QCD calculations and Monte Carlo models correctly describe the trends of the data at high Q2, but show quantitative discrepancies. The data show differences between the correlations in deep inelastic scattering and e+e- annihilation.Comment: 26 pages including 10 figures (submitted to Eur. J. Phys. C

Two-Higgs Leptonic Minimal Flavour Violation

We construct extensions of the Standard Model with two Higgs doublets, where there are flavour changing neutral currents both in the quark and leptonic sectors, with their strength fixed by the fermion mixing matrices $V_{CKM}$ and $V_{PMNS}$. These models are an extension to the leptonic sector of the class of models previously considered by Branco, Grimus and Lavoura, for the quark sector. We consider both the cases of Dirac and Majorana neutrinos and identify the minimal discrete symmetry required in order to implement the models in a natural way.Comment: 25 pages. No figure

ATP release via anion channels

ATP serves not only as an energy source for all cell types but as an ‘extracellular messenger-for autocrine and paracrine signalling. It is released from the cell via several different purinergic signal efflux pathways. ATP and its Mg2+ and/or H+ salts exist in anionic forms at physiological pH and may exit cells via some anion channel if the pore physically permits this. In this review we survey experimental data providing evidence for and against the release of ATP through anion channels. CFTR has long been considered a probable pathway for ATP release in airway epithelium and other types of cells expressing this protein, although non-CFTR ATP currents have also been observed. Volume-sensitive outwardly rectifying (VSOR) chloride channels are found in virtually all cell types and can physically accommodate or even permeate ATP4- in certain experimental conditions. However, pharmacological studies are controversial and argue against the actual involvement of the VSOR channel in significant release of ATP. A large-conductance anion channel whose open probability exhibits a bell-shaped voltage dependence is also ubiquitously expressed and represents a putative pathway for ATP release. This channel, called a maxi-anion channel, has a wide nanoscopic pore suitable for nucleotide transport and possesses an ATP-binding site in the middle of the pore lumen to facilitate the passage of the nucleotide. The maxi-anion channel conducts ATP and displays a pharmacological profile similar to that of ATP release in response to osmotic, ischemic, hypoxic and salt stresses. The relation of some other channels and transporters to the regulated release of ATP is also discussed

Search for Resonance Decays to Lepton+jet at DESY HERA and Limits on Leptoquarks

A search for narrow-width resonances that decay into electron+jet or neutrino+jet has been performed with the ZEUS detector at the DESY ep collider HERA operating at center-of-mass energies of 300 and 318 GeV. An integrated e+p luminosity of 114.8 pb-1 and e-p luminosity of 16.7 pb-1 were used. No evidence for any resonance was found. Limits were derived on the Yukawa coupling λ as a function of the mass of a hypothetical resonance that has arbitrary decay branching ratios into eq or vq. These limits also apply to squarks predicted by R-parity-violating supersymmetry. Limits for the production of leptoquarks described by the Buchmüller-Rückl-Wyler model were also derived for masses up to 400 GeV. For λ = 0.1, leptoquark masses up to 290 GeV are excluded