154 research outputs found
Elastic Form Factors of He up to Large
Elastic electron scattering off He and He has recently been studied
at forward and backward scattering angles in Hall A at JLab. The results will
provide accurate data on the elastic form factors, charge and magnetic for
He and charge only for He, up to squared momentum transfer -values
of 3.2 GeV.Comment: 3 pages, Proceedings of EFB2
Extensive Copy-Number Variation of Young Genes across Stickleback Populations
MM received funding from the Max Planck innovation funds for this project. PGDF was supported by a Marie Curie European Reintegration Grant (proposal nr 270891). CE was supported by German Science Foundation grants (DFG, EI 841/4-1 and EI 841/6-1). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
14-3-3 Mediates Histone Cross-Talk during Transcription Elongation in Drosophila
Post-translational modifications of histone proteins modulate the binding of transcription regulators to chromatin. Studies in Drosophila have shown that the phosphorylation of histone H3 at Ser10 (H3S10ph) by JIL-1 is required specifically during early transcription elongation. 14-3-3 proteins bind H3 only when phosphorylated, providing mechanistic insights into the role of H3S10ph in transcription. Findings presented here show that 14-3-3 functions downstream of H3S10ph during transcription elongation. 14-3-3 proteins localize to active genes in a JIL-1âdependent manner. In the absence of 14-3-3, levels of actively elongating RNA polymerase II are severely diminished. 14-3-3 proteins interact with Elongator protein 3 (Elp3), an acetyltransferase that functions during transcription elongation. JIL-1 and 14-3-3 are required for Elp3 binding to chromatin, and in the absence of either protein, levels of H3K9 acetylation are significantly reduced. These results suggest that 14-3-3 proteins mediate cross-talk between histone phosphorylation and acetylation at a critical step in transcription elongation
Gene Expression Responses Linked to Reproduction Effect Concentrations (EC10,20,50,90) of Dimethoate, Atrazine and Carbendazim, in Enchytraeus albidus
BACKGROUND: Molecular mechanisms of response to pesticides are scarce and information on such responses from soil invertebrates is almost inexistent. Enchytraeus albidus (Oligochaeta) is a standard soil ecotoxicology model species for which effects of many pesticides are known on survival, reproduction and avoidance behaviour. With the recent microarray development additional information can be retrieved on the molecular effects. METHODOLOGY/PRINCIPAL FINDINGS: Experiments were performed to investigate the transcription responses of E. albidus when exposed to three pesticides - dimethoate (insecticide), atrazine (herbicide) and carbendazim (fungicide) - in a range of concentrations that inhibited reproduction by 10%, 20%, 50% and 90% (EC(10), EC(20), EC(50) and EC(90), respectively). The goal of this study was to further identify key biological processes affected by each compound and if dose-related. All three pesticides significantly affected biological processes like translation, regulation of the cell cycle or general response to stress. Intracellular signalling and microtubule-based movement were affected by dimethoate and carbendazim whereas atrazine affected lipid and steroid metabolism (also by dimethoate) or carbohydrate metabolism (also by carbendazim). Response to DNA damage/DNA repair was exclusively affected by carbendazim. CONCLUSIONS: Changes in gene expression were significantly altered after 2 days of exposure in a dose-related manner. The mechanisms of response were comparable with the ones for mammals, suggesting across species conserved modes of action. The present results indicate the potential of using gene expression in risk assessment and the advantage as early markers
The deuteron: structure and form factors
A brief review of the history of the discovery of the deuteron in provided.
The current status of both experiment and theory for the elastic electron
scattering is then presented.Comment: 80 pages, 33 figures, submited to Advances in Nuclear Physic
Cyberbullying: a storm in a teacup?
Cyberbullying has been portrayed as a rising âepidemicâ amongst children and adolescents. But does it create many new victims beyond those already bullied with traditional means (physical, relational)? Our aim was to determine whether cyberbullying creates uniquely new victims, and whether it has similar impact upon psychological and behavioral outcomes for adolescents, beyond those experienced by traditional victims. This study assessed 2745 pupils, aged 11â16, from UK secondary schools. Pupils completed an electronic survey that measured bullying involvement, self-esteem and behavioral problems. Twenty-nine percent reported being bullied but only 1% of adolescents were pure cyber-victims (i.e., not also bullied traditionally). Compared to direct or relational victims, cyber-victimization had similar negative effects on behavior (z = â0.41) and self-esteem (z = â0.22) compared to those not involved in bullying. However, those bullied by multiple means (poly-victims) had the most difficulties with behavior (z = â0.94) and lowest self-esteem (z = â0.78). Cyberbullying creates few new victims, but is mainly a new tool to harm victims already bullied by traditional means. Cyberbullying extends the reach of bullying beyond the school gate. Intervention strategies against cyberbullying may need to include approaches against traditional bullying and its root causes to be successful.Published versio
MicroRNA Genes Derived from Repetitive Elements and Expanded by Segmental Duplication Events in Mammalian Genomes
MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate gene
expression by targeting mRNAs for translation repression or mRNA degradation.
Many miRNAs are being discovered and studied, but in most cases their origin,
evolution and function remain unclear. Here, we characterized miRNAs derived
from repetitive elements and miRNA families expanded by segmental duplication
events in the human, rhesus and mouse genomes. We applied a comparative genomics
approach combined with identifying miRNA paralogs in segmental duplication pair
data in a genome-wide study to identify new homologs of human miRNAs in the
rhesus and mouse genomes. Interestingly, using segmental duplication pair data,
we provided credible computational evidence that two miRNA genes are located in
the pseudoautosomal region of the human Y chromosome. We characterized all the
miRNAs whether they were derived from repetitive elements or not and identified
significant differences between the repeat-related miRNAs (RrmiRs) and
non-repeat-derived miRNAs in (1) their location in protein-coding and intergenic
regions in genomes, (2) the minimum free energy of their hairpin structures, and
(3) their conservation in vertebrate genomes. We found some lineage-specific
RrmiR families and three lineage-specific expansion families, and provided
evidence indicating that some RrmiR families formed and expanded during
evolutionary segmental duplication events. We also provided computational and
experimental evidence for the functions of the conservative RrmiR families in
the three species. Together, our results indicate that repetitive elements
contribute to the origin of miRNAs, and large segmental duplication events could
prompt the expansion of some miRNA families, including RrmiR families. Our study
is a valuable contribution to the knowledge of evolution and function of
non-coding region in genome
Measurement of the Generalized Polarizabilities of the Proton in Virtual Scattering at Q2=0.92 and 1.76 GeV2: I. Low Energy Expansion Analysis
Virtual Compton Scattering is studied at the Thomas Jefferson National
Accelerator Facility at low Center-of-Mass energies, below pion threshold.
Following the Low Energy Theorem for the process, we obtain
values for the two structure functions Pll-Ptt/epsilon and Plt at four-momentum
transfer squared Q2=0.92 and 1.76 GeV2.Comment: 4 pages, 2 figures, to be submitted to PRL. Figs 1 and 2, lettering
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Charged-particle distributions at low transverse momentum in âs=13 13 TeV pp interactions measured with the ATLAS detector at the LHC
Measurements of distributions of charged particles produced in protonâproton collisions with a centre-of-mass energy of 13 TeV are presented. The data were recorded by the ATLAS detector at the LHC and correspond to an integrated luminosity of 151 ÎŒb â1 ÎŒbâ1 . The particles are required to have a transverse momentum greater than 100 MeV and an absolute pseudorapidity less than 2.5. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity and the dependence of the mean transverse momentum on multiplicity are measured in events containing at least two charged particles satisfying the above kinematic criteria. The results are corrected for detector effects and compared to the predictions from several Monte Carlo event generators
Measurement of W+Wâ production in association with one jet in protonâproton collisions at sqrt(s) = 8TeV with the ATLAS detector
The production of W boson pairs in association with one jet in pp collisions at View the MathML sources=8 TeV is studied using data corresponding to an integrated luminosity of 20.3 fbâ1 collected by the ATLAS detector during 2012 at the CERN Large Hadron Collider. The cross section is measured in a fiducial phase-space region defined by the presence of exactly one electron and one muon, missing transverse momentum and exactly one jet with a transverse momentum above 25 GeV and a pseudorapidity of |η|<4.5|η|<4.5. The leptons are required to have opposite electric charge and to pass transverse momentum and pseudorapidity requirements. The fiducial cross section is found to be View the MathML sourceÏWWfid,1-jet=136±6(stat)±14(syst)±3(lumi) fb. In combination with a previous measurement restricted to leptonic final states with no associated jets, the fiducial cross section of WW production with zero or one jet is measured to be View the MathML sourceÏWWfid,â€1-jet=511±9(stat)±26(syst)±10(lumi) fb. The ratio of fiducial cross sections in final states with one and zero jets is determined to be 0.36±0.050.36±0.05. Finally, a total cross section extrapolated from the fiducial measurement of WW production with zero or one associated jet is reported. The measurements are compared to theoretical predictions and found in good agreement
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