5,593 research outputs found
Image Analysis Workflow for 2-D Electrophoresis Gels Based on ImageJ
A number of commercial software packages are currently available to perform digital two-dimensional electrophoresis (2D-GE) gel analysis. However, both the high cost of the commercial packages and the unavailability of a standard data analysis workflow, have prompted several groups to develop freeware systems to perform certain steps of gel analysis. Unfortunately, to the best of our knowledge none of them offer a package that performs all the steps envisaged in a 2D-GE gel analysis. Here we describe an ImageJ-based procedure, able to manage all the steps of a 2D-GE gel analysis. ImageJ is a free available image processing and analysis application developed by National Institutes of Health (NIH) and widely used in different life sciences fields as medical imaging, microscopy, western blotting and PAGE. Nevertheless no one has yet developed a procedure enabled to compare spots on 2D-GE gels. We collected all used ImageJ tools in a plug-in that allows us to perform the whole 2D-GE analysis. To test it, we performed a set of 2D-GE experiments on plasma samples from 9 patients victims of acute myocardial infarction and 8 controls, and we compared the results obtained by our procedure to those obtained using a widely diffuse commercial package, finding similar performance
Structural characterization of phytotoxic terpenoids from Cestrum parqui.
Isolation, chemical characterization and phytotoxicity of nine polyhydroxylated terpenes (five C13 nor-isoprenoids, two sesquiterpenes,
a spirostane and a pseudosapogenin) from Cestrum parqui LHerr are reported. In this work we completed the phytochemical
investigation of the terpenic fraction of the plant and described the structural elucidation of polar isoprenoids using NMR methods.
All the configurations of the compounds have been assigned by NOESY experiments. Four new structures have been identified as
(3S,5R,6R,7E,9R)-5,6,9-trihydroxy-3-isopropyloxy-7-megastigmene, 5a-spirostan-3b,12b,15a-triol, and 26-O-(30-isopentanoyl)-b-Dglucopyranosyl-
5a-furost-20(22)-ene-3b,26-diol, and as an unusual tricyclic sesquiterpene.
The compounds have been assayed for their phytotoxicity on lettuce at the concentrations ranging between 104 and 107 M. The
activities of some compounds were similar to that of the herbicide pendimethalin
Una ricerca online sulla soddisfazione degli utenti di AIB-WEB: metodologia e risultati
AIB-WEB, , il sito web dell\u2019Associazione italiana biblioteche, gestito internamente all\u2019Associazione con il contributo degli organi territoriali (sezioni regionali) e non territoriali (commissioni, gruppi, segreteria nazionale), promuove la conoscenza sulle attivit\ue0 associative e offre servizi a bibliotecari e altre tipologie di utenza, cui vengono forniti contenuti relativi al mondo dei bibliotecari e delle biblioteche. In occasione della decisione dell\u2019Associazione di procedere al restyling e alla ristrutturazione del sito
web istituzionale, passando da un modello statico di implementazione delle pagine all\u2019utilizzo di uno strumento dinamico, vale a dire a un CMS (Content Management System), si \ue8 deciso di effettuare un\u2019indagine sulla soddisfazione degli utenti di AIB-WEB, dalla cui analisi potessero emergere risultati utili per la rimodellazione del sito e il suo futuro arricchimento. Per la tecnica d\u2019indagine si \ue8 scelto di sfruttare la metodologia pi\uf9 diffusa e meno impegnativa sul piano delle risorse organizzative e finanziarie impegnate, ovvero l\u2019intervista standardizzata sotto forma di somministrazione di domande strutturate, proposte a tutti gli utenti per via telematica.
AIB-WEB, , the website of the Italian Library Association, is managed internally with the contribution of regional sections, committees, working groups, and the national secretariat. AIB-WEB disseminates social activities and offers services and professional contents to librarians and other users. Recently the Association management decided to carry on the restyling and restructuring of the institutional website, passing from a static model to a Content Management System (CMS). It was the right occasion to run a survey on AIB-WEB users\u2019 satisfaction, whose analysis would have provided suggestions about the improvement of the website under restyling.
It was decided to use the most diffused and less expensive methodology, the standardised interview, submitted through an online survey
Light composite Higgs boson from the normalized Bethe-Salpeter equation
Scalar composite boson masses have been computed in QCD and Technicolor
theories with the help of the homogeneous Bethe-Salpeter equation (BSE),
resulting in a scalar mass that is twice the dynamically generated fermion or
technifermion mass (). We show that in the case of walking (or
quasi-conformal) technicolor theories, where the behavior with the
momenta may be quite different from the one predicted by the standard operator
product expansion, this result is incomplete and we must consider the effect of
the normalization condition of the BSE to determine the scalar masses. We
compute the composite Higgs boson mass for several groups with technifermions
in the fundamental and higher dimensional representations and comment about the
experimental constraints on these theories, which indicate that models based on
walking theories with fermions in the fundamental representation may, within
the limitations of our approach, have masses quite near the actual direct
exclusion limit.Comment: 9 pages, 4 figures, minor corrections, to appear in Physical Review
A novel CMB polarization likelihood package for large angular scales built from combined WMAP and Planck LFI legacy maps
We present a CMB large-scale polarization dataset obtained by combining WMAP
Ka, Q and V with Planck 70 GHz maps. We employ the legacy frequency maps
released by the WMAP and Planck collaborations and perform our own Galactic
foreground mitigation technique, which relies on Planck 353 GHz for polarized
dust and on Planck 30 GHz and WMAP K for polarized synchrotron. We derive a
single, optimally-noise-weighted, low-residual-foreground map and the
accompanying noise covariance matrix. These are shown, through
analysis, to be robust over an ample collection of Galactic masks. We use this
dataset, along with the Planck legacy Commander temperature solution, to build
a pixel-based low-resolution CMB likelihood package, whose robustness we test
extensively with the aid of simulations, finding excellent consistency. Using
this likelihood package alone, we constrain the optical depth to reionazation
at C.L., on 54\% of the sky. Adding the
Planck high- temperature and polarization legacy likelihood, the Planck
lensing likelihood and BAO observations we find
in a full CDM exploration. The
latter bounds are slightly less constraining than those obtained employing
\Planck\ HFI CMB data for large angle polarization, that only include EE
correlations. Our bounds are based on a largely independent dataset that does
include also TE correlations. They are generally well compatible with Planck
HFI preferring slightly higher values of . We make the low-resolution
Planck and WMAP joint dataset publicly available along with the accompanying
likelihood code.Comment: The WMAP+LFI likelihood module is available on
\http://www.fe.infn.it/u/pagano/low_ell_datasets/wmap_lfi_legacy
Relating a gluon mass scale to an infrared fixed point in pure gauge QCD
We show that in pure gauge QCD (or any pure non-Abelian gauge theory) the
condition for the existence of a global minimum of energy with a gluon (gauge
boson) mass scale also implies the existence of a fixed point of the
function. We argue that the frozen value of the coupling constant found in some
solutions of the Schwinger-Dyson equations of QCD can be related to this fixed
point. We also discuss how the inclusion of fermions modifies this property.Comment: 4 pages, Revtex - Added some clarifying comments and new reference
Observing the intrinsic linewidth of a quantum-cascade laser: beyond the Schawlow-Townes limit
A comprehensive investigation of the frequency-noise spectral density of a
free-running mid-infrared quantum-cascade laser is presented for the first
time. It provides direct evidence of the leveling of this noise down to a white
noise plateau, corresponding to an intrinsic linewidth of a few hundred Hz. The
experiment is in agreement with the most recent theory on the fundamental
mechanism of line broadening in quantum-cascade lasers, which provides a new
insight into the Schawlow-Townes formula and predicts a narrowing beyond the
limit set by the radiative lifetime of the upper level.Comment: 4 pages, 4 figure
Single-Event Upset Analysis and Protection in High Speed Circuits
The effect of single-event transients (SETs) (at a combinational node of a design) on the system reliability is becoming a big concern for ICs manufactured using advanced technologies. An SET at a node of combinational part may cause a transient pulse at the input of a flip-flop and consequently is latched in the flip-flop and generates a soft-error. When an SET conjoined with a transition at a node along a critical path of the combinational part of a design, a transient delay fault may occur at the input of a flip-flop. On the other hand, increasing pipeline depth and using low power techniques such as multi-level power supply, and multi-threshold transistor convert almost all paths in a circuit to critical ones. Thus, studying the behavior of the SET in these kinds of circuits needs special attention. This paper studies the dynamic behavior of a circuit with massive critical paths in the presence of an SET. We also propose a novel flip-flop architecture to mitigate the effects of such SETs in combinational circuits. Furthermore, the proposed architecture can tolerant a single event upset (SEU) caused by particle strike on the internal nodes of a flip-flo
- …