Genotoxicity of Agricultural Soils after one year of Conversion Period and under Conventional Agriculture

Agricultural soils are often contaminated with genotoxic chemicals. Hence, transition to sustainable agriculture requires a conversion period. We performed a comparative evaluation of the soilgenotoxicity in a field after one year of conversion and in a field under conventional agriculture, not located close to sources of pollution. Soil samples were taken from 0-20 cm and 20-40 cm depth. Allium cepa-test system was used for the cytogenetic analysis. The higher mitotic index and lower frequency of chromosome aberrations in the samples from the field in conversion period compared with the field under conventional agriculture are indicative of a decrease of the soil genotoxicity. A slight increase in the frequency of aberrantcells and a substantial decrease in the mitotic index in 20-40 cm soil layer from both fields were observed. Regarding the field in conversion this might be due to the presence of agrochemicals used in the previous years, and indicates the necessity of longer conversion period. The results showed that Allium cepa-test might be wasused for monitoring of genotoxic pollution of the soils without preliminary extraction of the chemicals they contain

Lithological and petrophysical characteristics oil-saturated deposits of Bobrikovsky horizon on the southern slope of the South-Tatarian arc

Paper studied clastic reservoir rocks of the Bobrikovsky horizon on the southern slope of the South-Tatarian arc. Analysis of core material has shown that thickness of Bobrikovsky oil reservoirs are evolve along bearing and changed from 15 to 24 m. Cross sections is presented by interstratified beds of claystones, siltstones and sandstones. Sections are marked by regularity rise of sand layers thickness with increasing of aggregate thickness of Bobrikovsky deposits. Oil-productive anticlinal structures relate to lithological-structural type. In structure of oil reservoirs marked zones of oil-water contact, oil-saturated sands intervals and cap rocks. Oil-water contact zones mostly traced along bituminous layers in siltstones. Oil-saturated zones are represented by quartz sandstones in top of Bobrikovsky horizon and separated from water saturated underlying intervals by claystones. In some cases saturation of layers is uniform in other circumstances is banded. Cap rocks of oilsaturated deposits is claystones with changed thickness from 2 to 5 m. Higher in the succession claystones grade laterally to dense limestones of Tula horizon. Analysis of core material showed that the promising interval for production is sandstone layers (inferred age C1bb-2) in head part of Bobrikovsky horizon. Oil-saturated sandstones are evolving along bearing separated from each other by dense fluid seals. Reservoir sandstones on their petrophysical properties are porous reservoir middle and high capacity

Dolomite reservoir rocks of the bashkirian stage on the southern slope of the South-Tatarian arch

The southern slope of South-Tatarian Arc contains a lot of oil deposits in the Upper Paleozoic including old deposits in the Devonian and the Lower Carboniferous rocks and new deposits in the Middle Carboniferous rocks, especially, the deposits in the carbonate rocks within the Bashkirian stage. This carbonate object is considered as one of the perspective among the Middle Carboniferous rocks to prospect and develop on investigated area. Core investigations allowed to reveal that the most part of the best reservoir carbonate rocks was found in the zones of the dolomite mineralization. Three-six intervals of higher reservoir rocks properties were established in the sections of the Bashkirian stage. It was observed the decreasing trend in the dolomite mineralization from the center to the periphery of anticline traps. Two crystalline types (cellular and blastogene) of dolomite rocks were revealed

Дуготрајне промене трофије у бугарско-румунском делу Дунава и околних мочвара на територији бугарске током њене рестаурације

Based mainly on literature data and results of the monitoring program of the Bulgarian Ministry of Environment and Water, the long-term changes of nutrients (nitrogen and phosphorus), suspended solids and chlorophyll-concentrations in the Bulgarian–Romanian section of the Lower Danube during the period 1950–2014 were studied. The addition of more recent data from years 2008–2014 revealed stable lowering with values of PO4 3- concentrations close to those reported in the earliest 1962–1965 interval. The calculated load of dissolved inorganic nitrogen (DIN) showed a continuous but not significant decrease, while the PO4-P load dropped at the end of the 1950–2014 period to the values of its beginning. These changes of nitrogen and phosphorus led to a substantial shift of the N P-1 ratio towards phosphorus limitation of phytoplankton growth in the 2008–2014 period. The second part of the paper presented and analyzed the process of restoration of wetlands on the example of Srebarna Lake. The primary goal of this restoration was to sustain the valuable biodiversity supported by this lake, but as a wetland it should provide also most other services, one of which was nutrient removal. The monitoring of lake restoration started in 1990 and lasted with gaps until 2015. The main force driving the changes of other lake characteristics was the lake water level. Thus the lake water level correlated positively with water column transparency and negatively with chlorophyll-a, phytoplankton biovolume and the share of blue-greens from it. Since 1994 only one canal connected the lake with the Danube River, which seemed to be the reason for the limited success of the wetland restoration.На основу, пре свега, података из литературе и резултата програма праћења Министарства за животну средину и воде Бугарске, проучене су дугорочне промене нутријената (азота и фосфора), суспендованих чврстих честица и концентрација хлорофила у бугарско-румунском делу доњег тока Дунава током периода 1950–2014. године. Анализом и скоријих података за године 2008–2014, регистровано је стабилно снижавање са вредностима концентрација PO4 3- близу онима које су забележене у најранијем интервалу – у годинама 1962–1965. Израчунатo оптерећење раствореног неорганског азота (DIN) показало је стално, али не значајно смањење, док је оптерећење PO4-P пало крајем периода 1950–2014. на вредности са почетка. Те промене азота и фосфора довеле су до значајне промене показатеља N P-1 ка фосфорном ограничењу раста фитопланктона у периоду 2008–2014. године. У другом делу рада представљен је и анализиран процес санације мочварних подручја на примеру језера Сребарна. Главни циљ санације јесте одржавање вредног биодиверзитета који подржава то језеро; међутим, као мочварно подручје, оно треба да пружи и већину других услуга, које укључују, између осталог, уклањање нутријената. Праћење санације језера почело је 1990. и с прекидима трајало до 2015. године. Главни покретач промена других карактеристика језера био је ниво воде у језеру. Постојала је позитивна корелација између нивоа воде у језеру и прозирности воденог стуба и негативна корелација са хлорофилом а, биозапремином фитопланктона и уделом њихових плавозелених облика. Од 1994. године, само један канал повезује језеро са Дунавом, што вероватно представља разлог ограниченог успеха санације мочварног подручја.8. Конференција академија подунавске региј

SoLid: A short baseline reactor neutrino experiment

The SoLid experiment, short for Search for Oscillations with a Lithium-6 detector, is a new generation neutrino experiment which tries to address the key challenges for high precision reactor neutrino measurements at very short distances from a reactor core and with little or no overburden. The primary goal of the SoLid experiment is to perform a precise measurement of the electron antineutrino energy spectrum and flux and to search for very short distance neutrino oscillations as a probe of eV-scale sterile neutrinos. This paper describes the SoLid detection principle, the mechanical design and the construction of the detector. It then reports on the installation and commissioning on site near the BR2 reactor, Belgium, and finally highlights its performance in terms of detector response and calibration

Firms cash management, adjustment cost and its impact on firms’ speed of adjustment-A cross country analysis

We investigate the firms’ specific attributes that determine the difference in speed of adjustment (SOA) towards the cash holdings target in the Scandinavian countries: Denmark, Norway and Sweden. We examine whether Scandinavian firms maintain an optimal level of cash holdings and determine if the active cash holdings management is associated with the firms’ higher SOA and lower adjustment costs. Our findings substantiate that a higher level of off-target cost induces professional managers to rebalance their cash level towards the optimal balance of cash holdings. Our results reveal that Scandinavian firms accelerate SOA towards cash targets primarily for the precautionary motive. Moreover, our results show that SOA is heterogeneous across Scandinavian firms based on adjustment cost and deviate cash holdings towards the target mainly with the support of internal financing. Furthermore, our empirical findings show that the SOA of Norwegian firms is significantly higher than the Danish and Swedish firms

Commissioning and operation of the readout system for the solid neutrino detector

The SoLid experiment aims to measure neutrino oscillation at a baseline of 6.4 m from the BR2 nuclear reactor in Belgium. Anti-neutrinos interact via inverse beta decay (IBD), resulting in a positron and neutron signal that are correlated in time and space. The detector operates in a surface building, with modest shielding, and relies on extremely efficient online rejection of backgrounds in order to identify these interactions. A novel detector design has been developed using 12800 5 cm cubes for high segmentation. Each cube is formed of a sandwich of two scintillators, PVT and 6LiF:ZnS(Ag), allowing the detection and identification of positrons and neutrons respectively. The active volume of the detector is an array of cubes measuring 80x80x250 cm (corresponding to a fiducial mass of 1.6 T), which is read out in layers using two dimensional arrays of wavelength shifting fibres and silicon photomultipliers, for a total of 3200 readout channels. Signals are recorded with 14 bit resolution, and at 40 MHz sampling frequency, for a total raw data rate of over 2 Tbit/s. In this paper, we describe a novel readout and trigger system built for the experiment, that satisfies requirements on: compactness, low power, high performance, and very low cost per channel. The system uses a combination of high price-performance FPGAs with a gigabit Ethernet based readout system, and its total power consumption is under 1 kW. The use of zero suppression techniques, combined with pulse shape discrimination trigger algorithms to detect neutrons, results in an online data reduction factor of around 10000. The neutron trigger is combined with a large per-channel history time buffer, allowing for unbiased positron detection. The system was commissioned in late 2017, with successful physics data taking established in early 2018

Sox4 mediates Tbx3 transcriptional regulation of the gap junction protein Cx43

Tbx3, a T-box transcription factor, regulates key steps in development of the heart and other organ systems. Here, we identify Sox4 as an interacting partner of Tbx3. Pull-down and nuclear retention assays verify this interaction and in situ hybridization reveals Tbx3 and Sox4 to co-localize extensively in the embryo including the atrioventricular and outflow tract cushion mesenchyme and a small area of interventricular myocardium. Tbx3, SOX4, and SOX2 ChIP data, identify a region in intron 1 of Gja1 bound by all tree proteins and subsequent ChIP experiments verify that this sequence is bound, in vivo, in the developing heart. In a luciferase reporter assay, this element displays a synergistic antagonistic response to co-transfection of Tbx3 and Sox4 and in vivo, in zebrafish, drives expression of a reporter in the heart, confirming its function as a cardiac enhancer. Mechanistically, we postulate that Sox4 is a mediator of Tbx3 transcriptional activity

Performance of a full scale prototype detector at the BR2 reactor for the SoLid experiment

The SoLid collaboration has developed a new detector technology to detect electron anti-neutrinos at close proximity to the Belgian BR2 reactor at surface level. A 288 kg prototype detector was deployed in 2015 and collected data during the operational period of the reactor and during reactor shut-down. Dedicated calibration campaigns were also performed with gamma and neutron sources. This paper describes the construction of the prototype detector with a high control on its proton content and the stability of its operation over a period of several months after deployment at the BR2 reactor site. All detector cells provide sufficient light yields to achieve a target energy resolution of better than 20%/√E(MeV). The capability of the detector to track muons is exploited to equalize the light response of a large number of channels to a precision of 3% and to demonstrate the stability of the energy scale over time. Particle identification based on pulse-shape discrimination is demonstrated with calibration sources. Despite a lower neutron detection efficiency due to triggering constraints, the main backgrounds at the reactor site were determined and taken into account in the shielding strategy for the main experiment. The results obtained with this prototype proved essential in the design optimization of the final detector

Development of a quality assurance process for the SoLid experiment

The SoLid experiment has been designed to search for an oscillation pattern induced by a light sterile neutrino state, utilising the BR2 reactor of SCK⋅CEN, in Belgium. The detector leverages a new hybrid technology, utilising two distinct scintillators in a cubic array, creating a highly segmented detector volume. A combination of 5 cm cubic polyvinyltoluene cells, with 6LiF:ZnS(Ag) sheets on two faces of each cube, facilitate reconstruction of the neutrino signals. Whilst the high granularity provides a powerful toolset to discriminate backgrounds; by itself the segmentation also represents a challenge in terms of homogeneity and calibration, for a consistent detector response. The search for this light sterile neutrino implies a sensitivity to distortions of around Script O(10)% in the energy spectrum of reactor bar nue. Hence, a very good neutron detection efficiency, light yield and homogeneous detector response are critical for data validation. The minimal requirements for the SoLid physics program are a light yield and a neutron detection efficiency larger than 40 PA/MeV/cube and 50% respectively. In order to guarantee these minimal requirements, the collaboration developed a rigorous quality assurance process for all 12800 cubic cells of the detector. To carry out the quality assurance process, an automated calibration system called CALIPSO was designed and constructed. CALIPSO provides precise, automatic placement of radioactive sources in front of each cube of a given detector plane (16×16 cubes). A combination of 22Na, 252Cf and AmBe gamma and neutron sources were used by CALIPSO during the quality assurance process. Initially, the scanning identified defective components allowing for repair during initial construction of the SoLid detector. Secondly, a full analysis of the calibration data revealed initial estimations for the light yield of over 60 PA/MeV and neutron reconstruction efficiency of 68%, validating the SoLid physics requirements