Measurement of the temperature dependence of pulse lengths in an n-type germanium detector

The temperature dependence of the pulse length was measured for an 18-fold segmented n-type germanium detector in the temperature range of 77-120 K. The interactions of 122 keV photons originating from a Europium-152 source were selected and pulses as observed on the core and segment electrodes were studied. In both cases, the temperature dependence can be well described by a Boltzmann-like ansatz.Comment: 17 pages, 2 tables, 13 figures, published in EPJ A

Signal recognition efficiencies of artificial neural-network pulse-shape discrimination in HPGe 0νββ0\nu\beta\beta-decay searches

A pulse-shape discrimination method based on artificial neural networks was applied to pulses simulated for different background, signal and signal-like interactions inside a germanium detector. The simulated pulses were used to investigate variations of efficiencies as a function of used training set. It is verified that neural networks are well-suited to identify background pulses in true-coaxial high-purity germanium detectors. The systematic uncertainty on the signal recognition efficiency derived using signal-like evaluation samples from calibration measurements is estimated to be 5\%. This uncertainty is due to differences between signal and calibration samples

Examining c-di-GMP and possible quorum sensing regulation in Pseudomonas fluorescens SBW25:links between intra and inter-cellular regulation benefits community cooperative activities such as biofilm formation

Bacterial success in colonizing complex environments requires individual response to micro-scale conditions as well as community-level cooperation to produce large-scale structures such as biofilms. Connecting individual and community responses could be achieved by linking the intracellular sensory and regulatory systems mediated by bis-(3′-5′)-cyclic dimeric guanosine monophosphate (c-di-GMP) and other compounds of individuals with intercellular quorum sensing (QS) regulation controlling populations. There is growing evidence to suggest that biofilm formation by many pseudomonads is regulated by both intra and intercellular systems, though in the case of the model Pseudomonas fluorescens SBW25 Wrinkly Spreader in which mutations increasing c-di-GMP levels result in the production of a robust cellulose-based air-liquid interface biofilm, no evidence for the involvement of QS regulation has been reported. However, our recent review of the P. fluorescens SBW25 genome has identified a potential QS regulatory pathway and other QS–associated genes linked to c-di-GMP homeostasis, and QS signal molecules have also been identified in culture supernatants. These findings suggest a possible link between c-di-GMP and QS regulation in P. fluorescens SBW25 which might allow a more sophisticated and responsive control of cellulose production and biofilm formation when colonising the soil and plant-associated environments P. fluorescens SBW25 normally inhabits.Анализ ц-ди-ГМФ и возможного чувства кворума у Pseudomonas fluorescens SBW 25: связь между внутри и межклеточной регуляцией способствует кооперативному поведению в сообществе и формированию биоплёнкиУспешность бактериальной колонизации сложных экониш требует индивидуального ответа на изменения условий на микроуровне равно как и кооперации на уровне сообщества для продукции таких крупно масштабных структур как биоплёнки. Координация индивидуальных ответ ов и ответов сообщества может быть достигнута путем связывания внутриклеточных сенсорных и регуляторных систем, опосредуемых бис-(3',5')-циклическим димерным гуанозинмонофосфатом (ц-ди-ГМФ) и другими соединениями индивидуумов с межклеточной регуляцией - чувством кворума (ЧК), контролирующем популяци ю. Накапливается всё больше доказательств того, что формирование биопленки многими псевдомонадами регулируется как внутри клеточными, так и меж клеточными регуляторными системами, хотя в случае модельной Pseudomonas fluorescens SBW25 Wrinkly Spreader, у которой мутации, повышающ ие уровни ц-ди-ГМФ, приводят к созданию прочной целлюлозной биоплёнки на границе раздела фаз воздух-жидкость, не было обнаружено ни ка кого свидетельства вовлечения кворум-зависимой регуляции. Однако наш недавний обзор генома P. fluorescens SBW25 выявил потенциальный ЧК-зависимый регуляторный пу ть и другие ЧК-зависимые гены, связанные с гомеостазом ц-ди-ГМФ, а молекулы ЧК-сигналинга были идентифицированы в культуре. Эти данные свидетельствуют о возможной связи между ц-ди-ГМФ-регуляцией и ЧК у P. fluorescens SBW25, что позволяет более сложный и гибкий контроль над продукцией целлюлозы и образовани ем биопленки при колонизации почв и экониш, aссоциированных с растениям и, - естественными средами обитания P. fluorescens SBW25

Organized derivatives market and economical growth: Relationship and impact

Derivatives have become common instruments for a wide range of users, including financial institutions, companies that manage assets, corporations, hedge funds. These instruments allow for speculative, arbitrage and hedging operations, which defines them as useful instruments to stimulate the growth of the efficiency of financial markets and the real economy. In this article based on 21 macroeconomic and financial indexes of the USA by test of Granger’s relation of cause and effect have been investigated influences of the exchange market of derivatives on indicators of economic growth of the USA. In this article is used a large amount of statistical data of time series and variables of macroeconomic and financial indices. The results of a research have confirmed positive correlation and causality of indicators of economic growth from use of exchange derivatives in real economy. It is received for the studied period of 2000-2015 proofs that the exchange market of derivatives of the USA positively influences the economic. The results obtained during the study can be used to substantiate the necessary measures aimed on the development of the derivatives market in Ukraine

The MGDO software library for data analysis in Ge neutrinoless double-beta decay experiments

The GERDA and Majorana experiments will search for neutrinoless double-beta decay of germanium-76 using isotopically enriched high-purity germanium detectors. Although the experiments differ in conceptual design, they share many aspects in common, and in particular will employ similar data analysis techniques. The collaborations are jointly developing a C++ software library, MGDO, which contains a set of data objects and interfaces to encapsulate, store and manage physical quantities of interest, such as waveforms and high-purity germanium detector geometries. These data objects define a common format for persistent data, whether it is generated by Monte Carlo simulations or an experimental apparatus, to reduce code duplication and to ease the exchange of information between detector systems. MGDO also includes general-purpose analysis tools that can be used for the processing of measured or simulated digital signals. The MGDO design is based on the Object-Oriented programming paradigm and is very flexible, allowing for easy extension and customization of the components. The tools provided by the MGDO libraries are used by both GERDA and Majorana.Comment: 4 pages, 1 figure, proceedings for TAUP201

Aluminum as a source of background in low background experiments

Neutrinoless double beta decay would be a key to understanding the nature of neutrino masses. The next generation of High Purity Germanium experiments will have to be operated with a background rate of better than 10^-5 counts/(kg y keV) in the region of interest around the Q value of the decay. Therefore, so far irrelevant sources of background have to be considered. The metalization of the surface of germanium detectors is in general done with aluminum. The background from the decays of 22Na, 26Al, 226Ra and 228Th introduced by this metalization is discussed. It is shown that only a special selection of aluminum can keep these background contributions acceptable.Comment: 11 pages, 3 Tables, 11 Figures, accepted for publication in NIM