131 research outputs found

    Daily dynamics of cellulase activity in arable soils depending on management practices

    Get PDF
    The daily dynamics of cellulase activity was studied during 27 days by the cellophane membrane method on soils managed using the conventional high-input farming system (application of mineral fertilizers and pesticides) and the biological conservation farming system (application of organic fertilizers alone) in a microfield experiment. The regular oscillatory dynamics of the cellulase activity were revealed and confirmed by the harmonic (Fourier) analysis. The oscillatory dynamics of the cellulase activity had a self-oscillatory nature and was not directly caused by the disturbing impacts of both the uncontrolled (natural) changes in the temperature and moisture (rainfall) and the controlled ones (the application of different fertilizers). The disturbing impacts affected the oscillation amplitude of the cellulase activity but not the frequency (periods) of the oscillations. The periodic oscillations of the cellulase activity were more significant in the soil under the high-input management compared to the soil under the biological farming syste

    Oil pollution in the southeastern Baltic Sea by satellite remote sensing data in 2004-2015

    Get PDF
    The results of satellite monitoring of oil pollution in the Southeastern Baltic Sea in 2004-2015 are discussed in the paper. Interannual and seasonal variability of oil pollution is investigated. A steady decrease in total oil pollution was observed from 2004 to 2011. After a sharp increase of oil pollution in 2012, oil pollution level has established at 0.39 PI Index. Maximum of oil spills is observed in the spring and summer, which is probably due to favorable weather conditions for the detection of oil spills on radar images. According to the analysis of the shapes of the detected oil spills, it was concluded that the main polluters of the sea surface are vessels. No oil spills originated from the oil platform D-6 was detected in 2004-2015. Results of numerical experiments with the Seatrack Web oil spill model show that in the case of potential discharge of oil from the D-6 platform, oil will not reach the Curonian Spit beaches during 48 h after an accident

    Oil pollution of the southeastern Baltic Sea by satellite remote sensing data and in-situ measurements

    Get PDF
    Results of operational satellite monitoring of oil pollution of the sea surface together with in-situ measurements of the oil products concentration in the water column for the first time allowed to establish relation between the surface pollution originated from ships, and the general characteristics of spatial and temporal distribution of oil products in the water column in the Southeastern Baltic Sea. Areas with heightened concentrations of oil products in the surface and bottom layers were determined for the study area. The main directions of the contamination propagation are agreed with the main direction of annual mean transport of substances in the Gdansk Basin

    Описание клинических случаев меланомы кожи

    Get PDF
    Skin melanoma is a malignant tumor originating in the cells of the melanocytic system, which is characterized by an aggressive clinical course, significant metastatic potential and unfavorable prognosis. These features of the tumor stipulate the need to improve measures to optimize early diagnosis of tumors. The article presents cases of pigmented skin melanoma to demonstrate the variability of clinical manifestations of this tumor requiring dermatologist skills in the differential diagnostics of neoplasms.Меланома кожи - злокачественное новообразование, происходящее из клеток меланоцитарной системы, характеризуется агрессивным клиническим течением, значительным метастатическим потенциалом, неблагоприятным прогнозом. Данные особенности опухоли указывают на необходимость совершенствования мер по оптимизации ранней диагностики новообразования. Описаны случаи пигментной меланомы кожи с целью демонстрации вариабельности клинических проявлений данного новообразования, требующих от врача-дерматолога навыков его дифференциальной диагностики

    Search for Solar Axions Produced by Primakoff Conversion Using Resonant Absorption by 169^{169}Tm Nuclei

    Get PDF
    The search for resonant absorption of the Primakoff solar axions by 169^{169}Tm nuclei have been performed. Such an absorption should lead to the excitation of low-lying nuclear energy level: A+169A+^{169}Tm 169\to ^{169}Tm^* 169\to ^{169}Tm+γ + \gamma (8.41 keV). The Si(Li) detector and 169^{169}Tm target placed inside the low-background setup were used for that purpose. As a result, a new restriction on the axion-photon coupling and axion mass was obtained: gAγ(GeV1)mA(eV)1.36105g_{A\gamma}({GeV}^{-1})\cdot m_A(eV)\leq1.36\cdot10^{-5} (90% c.l.). In model of hadronic axion this restriction corresponds to the upper limit on axion mass - mAm_A\leq 191 eV for 90% c.l.Comment: 6 pages, 5 figures, submitted to Physics Letters

    Light Yield in DarkSide-10: a Prototype Two-phase Liquid Argon TPC for Dark Matter Searches

    Full text link
    As part of the DarkSide program of direct dark matter searches using liquid argon TPCs, a prototype detector with an active volume containing 10 kg of liquid argon, DarkSide-10, was built and operated underground in the Gran Sasso National Laboratory in Italy. A critically important parameter for such devices is the scintillation light yield, as photon statistics limits the rejection of electron-recoil backgrounds by pulse shape discrimination. We have measured the light yield of DarkSide-10 using the readily-identifiable full-absorption peaks from gamma ray sources combined with single-photoelectron calibrations using low-occupancy laser pulses. For gamma lines of energies in the range 122-1275 keV, we get consistent light yields averaging 8.887+-0.003(stat)+-0.444(sys) p.e./keVee. With additional purification, the light yield measured at 511 keV increased to 9.142+-0.006(stat) p.e./keVee.Comment: 10 pages, 7 figures, Accepted for publication in Astroparticle Physic

    Satellite Monitoring Systems for Shipping and Offshore Oil and Gas Industry in the Baltic Sea

    No full text
    Shipping activities, oil production and transport in the sea, oil handled in harbors, construction and exploitation of offshore oil and gas pipelines have a number of negative impacts on the marine environment and coastal zone of the seas. In 2004-2014 we elaborated several operational satellite monitoring systems for oil and gas companies in Russia and performed integrated satellite monitoring of the ecological state of coastal waters in the Baltic, Black, Caspian, and Kara seas, which included observation of oil pollution, suspended matter, and algae bloom at a fully operational mode. These monitoring systems differ from the existing ones by the analysis of a wide spectrum of satellite, meteorological and oceanographic data, as well as by a numerical modeling of oil spill transformation and transport in real weather conditions. Our experience in the Baltic Sea includes: (1) integrated satellite monitoring of oil production at the LUKOIL-KMN Ltd. D-6 oil rig in the Southeastern Baltic Sea (Kravtsovskoe oil field) in 2004-2014; (2) integrated satellite monitoring of the “Nord Stream” underwater gas pipeline construction and exploitation in the Gulf of Finland (2010-2013); (3) numerical modeling of risks of oil pollution caused by shipping along the main maritime shipping routes in the Gulf of Finland, the Baltic Proper, and in the Southeastern Baltic Sea; (4) numerical modeling of risks of oil pollution caused by oil production at D-6 oil rig and oil transportation on shore via the connecting underwater oil pipeline

    Daily dynamics of cellulase activity in arable soils depending on management practices

    No full text
    The daily dynamics of cellulase activity was studied during 27 days by the cellophane membrane method on soils managed using the conventional high-input farming system (application of mineral fertilizers and pesticides) and the biological conservation farming system (application of organic fertilizers alone) in a microfield experiment. The regular oscillatory dynamics of the cellulase activity were revealed and confirmed by the harmonic (Fourier) analysis. The oscillatory dynamics of the cellulase activity had a self-oscillatory nature and was not directly caused by the disturbing impacts of both the uncontrolled (natural) changes in the temperature and moisture (rainfall) and the controlled ones (the application of different fertilizers). The disturbing impacts affected the oscillation amplitude of the cellulase activity but not the frequency (periods) of the oscillations. The periodic oscillations of the cellulase activity were more significant in the soil under the high-input management compared to the soil under the biological farming syste
    corecore