141 research outputs found

    Порівняльна оцінка якості кролятини, отриманої в умовах забійного підприємства і приватного сектору

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    Recently, healthy food products, include rabbit meat, are becoming increasingly popular consumers. Given the large percentage of households producing rabbit meat, as well as the development of relevant enterprises, the issue of quality of rabbit meat obtained under various technological conditions is relevant. The research material was two groups of Californian breed rabbits: the first (I) in the amount of 32 animals from a small rabbit farm city, the second (II) in the amount of 60 animals from a rabbit breeding and processing enterprise in the Dnipro. The experience consisted of determining: technological features of the slaughter and primary processing of rabbits, meat production and quality characteristics of rabbit meat, as well as slaughter veterinary and sanitary examination and histomorphological research. The general patterns of slaughter and primary processing of rabbits of both groups were generally similar and consistent with the requirements. The differences are defined in the methods of stunning, bleeding, toilet carcasses and preparing them for storage. A quick and effective method of bleeding rabbits of group II led to blood contamination of the skins, while in group I the skins remained clean. The dressing out percentage of rabbit backyard slaughter was 6.2 % higher (P < 0.001) than at the enterprise, and, conversely, the loss of carcass meat juice after cooling was 3.24 % less (P < 0.01) in production than in the small farm. The decrease in meat pH at the extreme minimum values per day after slaughter in the 1st group was more intense than in the 2nd group: 5.72 and 5.93 (P <0.001), respectively. The influence of the conditions for the production of rabbit meat on the moisture and protein content in meat was not revealed. The pathological changes common to both groups of rabbits were characterized by the detection of hematomas, subcutaneous abscesses in carcasses (9.4 % and 5.0 % of cases), hepatic coccidiosis (12.5 % and 18.3 %). A significant difference was found in pathological changes in the lungs: the incidence of hemoaspiration of the lungs of rabbit slaughter was 16.5 times higher than that of rabbits slaughtered under production conditions.Останнім часом все більш затребуваними споживачами стають продукти здорового харчування, до яких фахівці зараховують кролятину. Враховуючи великий відсоток господарств населення з виробництва м’яса кролів, а також розвиток відповідних підприємств, актуальним є питання порівняльної характеристики якості кролятини, отриманої за різних технологічних умов. Матеріалом дослідження були дві групи кролів каліфорнійської породи: перша (I) у кількості 32 тварини із кролеферми приватного сектору міста Дніпра, друга (II) – у кількості 60 тварин із підприємства з вирощування і переробки кролів міста Дніпра. Дослід складався з визначення: технологічних особливостей забою і первинної переробки кролів, м’ясних продуктивних та якісних характеристик кролятини, а також післязабійної ветеринарно-санітарної експертизи та гістоморфологічного дослідження. Загальні схеми забою і первинної переробки кролів обох груп загалом були схожі й відповідали вимогам. Відмінності визначені у способах оглушення, знекровлення, туалету тушок та підготовки їх до зберігання. Швидкий та ефективний спосіб знекровлення кролів II групи приводив до забруднення кров’ю шкурок, тимчасом як в I групі шкури залишалися чистими. Забійний вихід тушок кролів подвірного забою був вищим на 6,2 % (Р < 0,001), ніж на підприємстві і, навпаки, втрати м’ясного соку тушки після охолодження були меншими на 3,24 % (Р < 0,01) на виробництві, ніж у господарстві приватного сектору. Зниження рН м’яса до крайніх мінімальних значень через добу після забою в I групі було інтенсивнішим, ніж в II групі: 5,72 і 5,93 (Р < 0,001) відповідно. Не виявлено впливу умов виробництва кролятини на вміст вологи і білка в м’ясі. Спільні для обох груп кролів патологічні зміни характеризувались виявленням гематом, підшкірних абсцесів на тушках (9,4 % і 5,0 % випадків), еймеріозом печінки (12,5 % і 18,3 %). Суттєва різниця виявлена в патологічних змінах легень: частота випадків гемоаспірації легень кролів подвірного забою була в 16,5 разу вищою, ніж у кролів, забитих у виробничих умовах

    Langmuir wave linear evolution in inhomogeneous nonstationary anisotropic plasma

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    Equations describing the linear evolution of a non-dissipative Langmuir wave in inhomogeneous nonstationary anisotropic plasma without magnetic field are derived in the geometrical optics approximation. A continuity equation is obtained for the wave action density, and the conditions for the action conservation are formulated. In homogeneous plasma, the wave field E universally scales with the electron density N as E ~ N^{3/4}, whereas the wavevector evolution varies depending on the wave geometry

    Characterization of 30 76^{76}Ge enriched Broad Energy Ge detectors for GERDA Phase II

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    The GERmanium Detector Array (GERDA) is a low background experiment located at the Laboratori Nazionali del Gran Sasso in Italy, which searches for neutrinoless double beta decay of 76^{76}Ge into 76^{76}Se+2e^-. GERDA has been conceived in two phases. Phase II, which started in December 2015, features several novelties including 30 new Ge detectors. These were manufactured according to the Broad Energy Germanium (BEGe) detector design that has a better background discrimination capability and energy resolution compared to formerly widely-used types. Prior to their installation, the new BEGe detectors were mounted in vacuum cryostats and characterized in detail in the HADES underground laboratory in Belgium. This paper describes the properties and the overall performance of these detectors during operation in vacuum. The characterization campaign provided not only direct input for GERDA Phase II data collection and analyses, but also allowed to study detector phenomena, detector correlations as well as to test the strength of pulse shape simulation codes.Comment: 29 pages, 18 figure

    Background free search for neutrinoless double beta decay with GERDA Phase II

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    The Standard Model of particle physics cannot explain the dominance of matter over anti-matter in our Universe. In many model extensions this is a very natural consequence of neutrinos being their own anti-particles (Majorana particles) which implies that a lepton number violating radioactive decay named neutrinoless double beta (0νββ0\nu\beta\beta) decay should exist. The detection of this extremely rare hypothetical process requires utmost suppression of any kind of backgrounds. The GERDA collaboration searches for 0νββ0\nu\beta\beta decay of 76^{76}Ge (^{76}\rm{Ge} \rightarrow\,^{76}\rm{Se} + 2e^-) by operating bare detectors made from germanium with enriched 76^{76}Ge fraction in liquid argon. Here, we report on first data of GERDA Phase II. A background level of 103\approx10^{-3} cts/(keV\cdotkg\cdotyr) has been achieved which is the world-best if weighted by the narrow energy-signal region of germanium detectors. Combining Phase I and II data we find no signal and deduce a new lower limit for the half-life of 5.310255.3\cdot10^{25} yr at 90 % C.L. Our sensitivity of 4.010254.0\cdot10^{25} yr is competitive with the one of experiments with significantly larger isotope mass. GERDA is the first 0νββ0\nu\beta\beta experiment that will be background-free up to its design exposure. This progress relies on a novel active veto system, the superior germanium detector energy resolution and the improved background recognition of our new detectors. The unique discovery potential of an essentially background-free search for 0νββ0\nu\beta\beta decay motivates a larger germanium experiment with higher sensitivity.Comment: 14 pages, 9 figures, 1 table; ; data, figures and images available at http://www.mpi-hd.mpg/gerda/publi

    The first search for bosonic super-WIMPs with masses up to 1 MeV/c2^2 with GERDA

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    We present the first search for bosonic super-WIMPs as keV-scale dark matter candidates performed with the GERDA experiment. GERDA is a neutrinoless double-beta decay experiment which operates high-purity germanium detectors enriched in 76^{76}Ge in an ultra-low background environment at the Laboratori Nazionali del Gran Sasso (LNGS) of INFN in Italy. Searches were performed for pseudoscalar and vector particles in the mass region from 60 keV/c2^2 to 1 MeV/c2^2. No evidence for a dark matter signal was observed, and the most stringent constraints on the couplings of super-WIMPs with masses above 120 keV/c2^2 have been set. As an example, at a mass of 150 keV/c2^2 the most stringent direct limits on the dimensionless couplings of axion-like particles and dark photons to electrons of gae<31012g_{ae} < 3 \cdot 10^{-12} and α/α<6.51024{\alpha'}/{\alpha} < 6.5 \cdot 10^{-24} at 90% credible interval, respectively, were obtained.Comment: 6 pages, 3 figures, submitted to Physical Review Letters, added list of authors, updated ref. [21

    The background in the neutrinoless double beta decay experiment GERDA

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    The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double beta decay of 76Ge. The signature of the signal is a monoenergetic peak at 2039 keV, the Q-value of the decay, Q_bb. To avoid bias in the signal search, the present analysis does not consider all those events, that fall in a 40 keV wide region centered around Q_bb. The main parameters needed for the neutrinoless double beta decay analysis are described. A background model was developed to describe the observed energy spectrum. The model contains several contributions, that are expected on the basis of material screening or that are established by the observation of characteristic structures in the energy spectrum. The model predicts a flat energy spectrum for the blinding window around Q_bb with a background index ranging from 17.6 to 23.8*10^{-3} counts/(keV kg yr). A part of the data not considered before has been used to test if the predictions of the background model are consistent. The observed number of events in this energy region is consistent with the background model. The background at Q-bb is dominated by close sources, mainly due to 42K, 214Bi, 228Th, 60Co and alpha emitting isotopes from the 226Ra decay chain. The individual fractions depend on the assumed locations of the contaminants. It is shown, that after removal of the known gamma peaks, the energy spectrum can be fitted in an energy range of 200 kev around Q_bb with a constant background. This gives a background index consistent with the full model and uncertainties of the same size

    The Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay (LEGEND)

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    The observation of neutrinoless double-beta decay (0νββ{\nu}{\beta}{\beta}) would show that lepton number is violated, reveal that neutrinos are Majorana particles, and provide information on neutrino mass. A discovery-capable experiment covering the inverted ordering region, with effective Majorana neutrino masses of 15 - 50 meV, will require a tonne-scale experiment with excellent energy resolution and extremely low backgrounds, at the level of \sim0.1 count /(FWHM\cdott\cdotyr) in the region of the signal. The current generation 76^{76}Ge experiments GERDA and the MAJORANA DEMONSTRATOR utilizing high purity Germanium detectors with an intrinsic energy resolution of 0.12%, have achieved the lowest backgrounds by over an order of magnitude in the 0νββ{\nu}{\beta}{\beta} signal region of all 0νββ{\nu}{\beta}{\beta} experiments. Building on this success, the LEGEND collaboration has been formed to pursue a tonne-scale 76^{76}Ge experiment. The collaboration aims to develop a phased 0νββ{\nu}{\beta}{\beta} experimental program with discovery potential at a half-life approaching or at 102810^{28} years, using existing resources as appropriate to expedite physics results.Comment: Proceedings of the MEDEX'17 meeting (Prague, May 29 - June 2, 2017

    Structural study of an amorphous NiZr2 alloy by anomalous wide angle X-ray scattering and Reverse Monte Carlo simulations

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    The local atomic structure of an amorphous NiZr2 alloy was investigated using the anomalous wide-angle x-ray scattering (AWAXS), differential anomalous scattering (DAS) and reverse Monte Carlo (RMC) simulations techniques. The AWAXS measurements were performed at eight different incident photon energies, including some close to the Ni and Zr K edges. From the measurements eight total structure factor S(K,E) were derived. Using the AWAXS data four differential structure factors DSFi(K,Em,En) were derived, two about the Ni and Zr edges. The partial structure factors SNi-Ni(K), SNi-Zr(K) and SZr-Zr(K) were estimated by using two different methods. First, the S(K,E) and DSFi(K,Em,En) factors were combined and used in a matrix inversion process. Second, three S(K,E) factors were used as input data in the RMC technique. The coordination numbers and interatomic distances for the first neighbors extracted from the partial structure factors obtained by these two methods show a good agreement. By using the three-dimensional structure derived from the RMC simulations, the bond-angle distributions were calculated and they suggest the presence of distorted triangular-faced polyhedral units in the amorphous NiZr2 structure. We have used the Warren chemical short-range order parameter to evaluate the chemical short-range order for the amorphous NiZr2 alloy and for the NiZr2 compound. The calculated values show that the chemical short-range order found in these two materials is similar to that found in a solid solution.Comment: Submitted to Phys. Rev. B, 8 figure

    Flux Modulations seen by the Muon Veto of the GERDA Experiment

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    The GERDA experiment at LNGS of INFN is equipped with an active muon veto. The main part of the system is a water Cherenkov veto with 66~PMTs in the water tank surrounding the GERDA cryostat. The muon flux recorded by this veto shows a seasonal modulation. Two effects have been identified which are caused by secondary muons from the CNGS neutrino beam (2.2 %) and a temperature modulation of the atmosphere (1.4 %). A mean cosmic muon rate of Iμ0=(3.477±0.002stat±0.067sys)×104I^0_{\mu} = (3.477 \pm 0.002_{\textrm{stat}} \pm 0.067_{\textrm{sys}}) \times 10^{-4}/(s\cdotm2^2) was found in good agreement with other experiments at LNGS at a depth of 3500~meter water equivalent.Comment: 7 pages, 6 figure
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