Electron microscopic visualization of tRNA genes with ferritin-avidin: biotin labels

A method is described for indirect electron microscopic visualization and mapping of tRNA and other short transcripts hybridized to DNA. This method depends upon the attachment of the electron-dense protein ferritin to the RNA, the binding being mediated by the remarkably strong association of the egg white protein avidin with biotin. Biotin is covalently attached to the 3' end of tRNA using an NH2 (CH2) 5NH2 bridge. The tRNA-biotin adduct is hybridized to complementcrry DNA sequences present in a single stranded nonhomology loop of a DNA:DNA heteroduplex. Avidin, covalently crosslinked to ferritin is mixed with the heteroduplex and becomes bound to the hybridized tRNA-biotin. Observation of the DNA:RNA-biotin:avidin-ferritin complex by electron microsdopy specifically and accurately reveals the position of the tRNA gene, with a frequency of labeling of approximately 50%

Validating the Demand Control Support Questionnaire among white-collar employees in Switzerland and the United States

Background: The Demand Control Support Questionnaire (DCSQ) is an established self-reported tool to measure a stressful work environment. Validated German and English versions are however currently missing. The aim of this study was therefore to evaluate the psychometric properties of German and English versions of the DCSQ among white-collar employees in Switzerland and the US. Methods: This cross-sectional study was carried out on 499 employees in Switzerland and 411 in the US, respectively. The 17-item DCSQ with three scales assessed psychosocial stress at work (psychological demands, decision latitude, and social support at work). Depressive symptoms were measured by the 2-item Patient Health Questionnaire. Cronbach’s α and item-total correlations tested the scale reliability (internal consistency). Construct validity of the questionnaire was examined using exploratory factor analysis (EFA). Logistic regressions estimated associations of each scale and job strain with depressive symptoms (criterion validity). Results: In both samples, all DCSQ scales presented satisfactory internal consistency (Cronbach’s α ≥ 0.72; item-total correlations ≥ 0.33), and EFA showed the 17 items loading on three factors, which is in line with the theoretically assumed structure of the DCSQ construct. Moreover, all three scales as well as high job strain were significantly associated with depressive symptoms. The associations were stronger in the US sample. Conclusions: The German and the English versions of the DCSQ seem to be reliable and valid instruments to measure psychosocial stress based on the job demand-control-support model in the workplace of white-collar employees in Switzerland and the US

Reservoir fracture characterizations from seismic scattered waves

The measurements of fracture parameters, such as fracture orientation, fracture density and fracture compliance, in a reservoir is very important for field development and exploration. Traditional seismic methods for fracture characterization include shear wave birefringence (Gaiser and Dok, 2001; Dok et al., 2001; Angerer et al., 2002; Vetri et al., 2003) and amplitude variations with offset and azimuth (AVOA) (Ruger, 1998; Shen et al., 2002; Hall et al., 2003; Liu et al., 2010; Lynn et al., 2010). These methods are based on the equivalent medium theory with the assumption that fracture dimension and spacing are small relative to the seismic wave length, so a fracture zone behaves like an equivalent anisotropic medium. But fractures on the order of seismic wave length are also very important for enhanced oil recovery, and they are one of the important subsurface scattering sources that generate scattered seismic waves. Willis et al. (2006) developed the Scattering Index method to extract the fracture scattering characteristics by calculating the transfer funtion of a fracture zone. Fang et al. (2011) proposed a modification of the SI method (the Fracture Transfer Function (FTF) method) that leads to a more robust fracture characterization. In this paper, we use both laboratory data and field data to explore the capability of the FTF method.Eni-MIT Energy Initiative Founding Member Progra

Исследование влияния природы растворителя, используемого при получении электродной мембраны, на работу Ni-селективного электрода при определении ионов никеля (LL) в водных средах

Исследовано влияние природы растворителей (бензиловый спирт и хлорфенол), используемых для изготовления полимерной электродной мембраны твердофазного никельселективного электрода на основе никельгексационоферратов ({Ni2[Fe(CN)6]}), иммобилизованных в полиэтилентерефталатную (ПЭТФ) матрицу для определения ионов никеля в водных средах. Установлено, что мембраны, полученные на основе бензилового спирта имеют более высокие электродные показатели по сходимости и воспроизводимости потенциалов, стабильности работы, низком дрейфе и времени отклика электрода по сравнению с мембранами на основе хлорфенола и могут быть рекомендованы к использованию в никель селективных электродах.The influence of the nature of the solvents (benzyl alcohol and chlorophenol) used to fabricate a polymer electrode membrane of a solid-phase nickel selective electrode based on nickelhexacetanoferrates ({Ni2 [Fe (CN) 6]}) immobilized in a polyethylene terephthalate (PET) matrix for the determination of nickel ions in aqueous media . It has been established that membranes obtained on the basis of benzyl alcohol have higher electrode indices for the convergence and reproducibility of potentials, stability of operation, low drift and electrode response time compared to chlorophenol-based membranes, and can be recommended for use in nickel selective electrodes

Implementation of REACH in the New Member States - Part two: Business Case Studies in Selected New Member States

This report informs about potential impacts of the European regulation concerning the registration, evaluation, authorisation and restriction of chemicals REACH (Regulation (EC) No 1907/2006) in the New Member States . It consists of two parts: 1) "Implementation of REACH in the New Member States – Part one: overview of the chemical and specialty chemical sector in the New Member States", and 2) "Implementation of REACH in the New Member States – Part two: Business case studies in selected New Member States". The first report gives a general overview of the chemical sector in all New Member States and provides key macroeconomic data for the description of the chemical sector as a whole in each of the countries. This includes the sectors development, major developments including trade with EU-15 and non-EU countries, and a description of sub-sectors according to NACE categories. Furthermore, the first report describes the impact on the chemical industry through the implementation of the Chemicals Acquis and the Accession to the EU, and derives the implications for the adoption of REACH in the New Member States. Finally, the report outlines REACH Impact studies which are available in the New Member States . The second report analyses the ability of specialty chemicals companies in selected countries to implement REACH . This ability is examined on the basis of techno-economic case studies. From the economic aspect, the impact on costs and prices is analysed, substance withdrawal, administrative impact, capacity needs and the competitiveness on European and international markets. From the technological point of view the impact of REACH on innovation, replacement of substances and process adaptation is looked at. The strategic analysis looked at alternatives to cope with REACH (such as the import of components, relocation to non-EU countries etc.), the potential of companies to adapt to the changing legal framework (including the implementation of the environmental acquis) and the relative importance of REACH as one amongst different drivers for change.JRC.J.2-Competitiveness and Sustainabilit

Zincfingerhomeobox is required for the differentiation of serotonergicneurons in the seaurchinembryo

Serotonergicneurons differentiate in the neurogenic animal plate ectoderm of the seaurchinembryo. The regulatory mechanisms that control the specification or differentiation of these neurons in the seaurchinembryo are not yet understood, although, after the genome was sequenced, many genes encoding transcription factors expressed in this region were identified. Here, we report that zincfingerhomeobox (zfhx1/z81) is expressed in serotonergic neural precursor cells, using double in situ hybridization screening with a serotonergic neural marker, tryptophan 5-hydroxylase (tph) encoding a serotonin synthase that is required for the differentiation of serotonergicneurons. zfhx1/z81 begins to be expressed at gastrula stage in individual cells in the anterior neuroectoderm, some of which also express delta. zfhx1/z81 expression gradually disappears as neural differentiation begins with tph expression. When the translation of Zfhx1/Z81 is blocked by morpholino injection, embryos express neither tph nor the neural marker synaptotagminB in cells of the animal plate, and serotonergicneurons do not differentiate. In contrast, Zfhx1/Z81 morphants do express fez, another neural precursor marker, which appears to function in the initial phase of specification/differentiation of serotonergicneurons. In addition, zfhx1/z81 is one of the targets suppressed in the animal plate by anti-neural signals such as Nodal as well as Delta-Notch. We conclude that Zfhx1/Z81 functions during the specification of individual anterior neural precursors and promotes the expression of tph and synaptotagminB, required for the differentiation of serotonergicneurons

ankAT-1 is a novel gene mediating the apical tuft formation in the sea urchin embryo

In sea urchin embryos, the apical tuft forms within the neurogenic animal plate. When FoxQ2, one of the earliest factors expressed specifically in the animal plate by early blastula stage, is knocked down, the structure of the apical tuft is altered. To determine the basis of this phenotype, we identified FoxQ2-dependent genes using microarray analysis. The most strongly down-regulated gene in FoxQ2 morphants encodes a protein with ankyrin repeats region in its N-terminal domain. We named this gene ankAT-1, Ankyrin-containing gene specific for Apical Tuft. Initially its expression in the animal pole region of very early blastula stage embryos is FoxQ2-independent but becomes FoxQ2-dependent beginning at mesenchyme blastula stage and continuing in the animal plate of 3-day larvae. Furthermore, like FoxQ2, this gene is expressed throughout the expanded apical tuft region that forms in embryos lacking nuclear β-catenin. When AnkAT-1 is knocked-down by injecting a morpholino, the cilia at the animal plate in the resulting embryos are much shorter and their motility is less than that of motile cilia in other ectoderm cells, and remains similar to that of long apical tuft cilia. We conclude that AnkAT-1 is involved in regulating the length of apical tuft cilia

Fast photon detection for the COMPASS RICH detector

The COMPASS experiment at the SPS accelerator at CERN uses a large scale Ring Imaging CHerenkov detector (RICH) to identify pions, kaons and protons in a wide momentum range. For the data taking in 2006, the COMPASS RICH has been upgraded in the central photon detection area (25% of the surface) with a new technology to detect Cherenkov photons at very high count rates of several 10^6 per second and channel and a new dead-time free read-out system, which allows trigger rates up to 100 kHz. The Cherenkov photons are detected by an array of 576 visible and ultra-violet sensitive multi-anode photomultipliers with 16 channels each. The upgraded detector showed an excellent performance during the 2006 data taking.Comment: Proceeding of the IPRD06 conference (Siena, Okt. 06

The Fast Read-out System for the MAPMTs of COMPASS RICH-1

A fast readout system for the upgrade of the COMPASS RICH detector has been developed and successfully used for data taking in 2006 and 2007. The new readout system for the multi-anode PMTs in the central part of the photon detector of the RICH is based on the high-sensitivity MAD4 preamplifier-discriminator and the dead-time free F1-TDC chip characterized by high-resolution. The readout electronics has been designed taking into account the high photon flux in the central part of the detector and the requirement to run at high trigger rates of up to 100 kHz with negligible dead-time. The system is designed as a very compact setup and is mounted directly behind the multi-anode photomultipliers. The data are digitized on the frontend boards and transferred via optical links to the readout system. The read-out electronics system is described in detail together with its measured performances.Comment: Proceeding of RICH2007 Conference, Trieste, Oct. 2007. v2: minor change