155 research outputs found
Experimental search for the LSND anomaly with the ICARUS detector in the CNGS neutrino beam
We report an early result from the ICARUS experiment on the search for nu_mu
to nu_e signal due to the LSND anomaly. The search was performed with the
ICARUS T600 detector located at the Gran Sasso Laboratory, receiving CNGS
neutrinos from CERN at an average energy of about 20 GeV, after a flight path
of about 730 km. The LSND anomaly would manifest as an excess of nu_e events,
characterized by a fast energy oscillation averaging approximately to
sin^2(1.27 Dm^2_new L/ E_nu) = 1/2. The present analysis is based on 1091
neutrino events, which are about 50% of the ICARUS data collected in 2010-2011.
Two clear nu_e events have been found, compared with the expectation of 3.7 +/-
0.6 events from conventional sources. Within the range of our observations,
this result is compatible with the absence of a LSND anomaly. At 90% and 99%
confidence levels the limits of 3.4 and 7.3 events corresponding to oscillation
probabilities of 5.4 10^-3 and 1.1 10^-2 are set respectively. The result
strongly limits the window of open options for the LSND anomaly to a narrow
region around (Dm^2, sin^2(2 theta))_new = (0.5 eV^2, 0.005), where there is an
overall agreement (90% CL) between the present ICARUS limit, the published
limits of KARMEN and the published positive signals of LSND and MiniBooNE
Collaborations.Comment: 10 pages, 7 figure
Low-basicity 5-HT7 receptor agonists synthesized using the van Leusen multicomponent protocol
A series of 5-aryl-1-alkylimidazole derivatives was synthesized using the van Leusen multicomponent
reaction. The chemotype is the first example of low-basicity scaffolds exhibiting high affinity for 5-HT7
receptor together with agonist function. The chosen lead compounds 3-(1-ethyl-1H-imidazol-5-yl)-5-
iodo-1H-indole (AGH-107, 1o, Ki 5-HT7=6nM, EC50=19nM, 176-fold selectivity over 5-HT1AR) and 1e
(5-methoxy analogue, Ki 5-HT7=30nM, EC50=60nM) exhibited high selectivity over related CNS targets,
high metabolic stability and low toxicity in HEK-293 and HepG2 cell cultures. A rapid absorption to the
blood, high blood-brain barrier permeation and a very high peak concentration in the brain (Cmax=2723
ng/g) were found for 1o after i.p. (5mg/kg) administration in mice. The compound was found active
in novel object recognition test in mice, at 0.5, 1 and 5mg/kg. Docking to 5-HT7R homology models
indicated a plausible binding mode which explain the unusually high selectivity over the related CNS
targets. Halogen bond formation between the most potent derivatives and the receptor is consistent
with both the docking results and SAR. 5-Chlorine, bromine and iodine substitution resulted in a 13, 27
and 89-fold increase in binding affinities, respectively, and in enhanced 5-HT1AR selectivity
Measurement of Through-Going Particle Momentum By Means Of Multiple Scattering With The ICARUS T600 TPC
The ICARUS collaboration has demonstrated, following the operation of a 600
ton (T600) detector at shallow depth, that the technique based on liquid Argon
TPCs is now mature. The study of rare events, not contemplated in the Standard
Model, can greatly benefit from the use of this kind of detectors. In
particular, a deeper understanding of atmospheric neutrino properties will be
obtained thanks to the unprecedented quality of the data ICARUS provides.
However if we concentrate on the T600 performance, most of the
charged current sample will be partially contained, due to the reduced
dimensions of the detector. In this article, we address the problem of how well
we can determine the kinematics of events having partially contained tracks.
The analysis of a large sample of atmospheric muons collected during the T600
test run demonstrate that, in case the recorded track is at least one meter
long, the muon momentum can be reconstructed by an algorithm that measures the
Multiple Coulomb Scattering along the particle's path. Moreover, we show that
momentum resolution can be improved by a factor two using an algorithm based on
the Kalman Filtering technique
Design and synthesis of new quinazolin-4-one derivatives with negative receptor modulation activity and antipsychotic-like properties
Following the glutamatergic theory of schizophrenia and based on our previous study regarding the antipsychotic-like activity of mGlu7 NAMs, we synthesized a new compound library containing 103 members, which were examined for NAM mGlu7 activity in the T-REx 293 cell line expressing a recombinant human mGlu7 receptor. Out of the twenty-two scaffolds examined, active compounds were found only within the quinazolinone chemotype. 2-(2-Chlorophenyl)-6-(2,3-dimethoxyphenyl)-3-methylquinazolin-4(3H)-one (A9-7, ALX-171, mGlu7 IC50 = 6.14 µM) was selective over other group III mGlu receptors (mGlu4 and mGlu8), exhibited satisfactory drug-like properties in preliminary DMPK profiling, and was further tested in animal models of antipsychotic-like activity, assessing the positive, negative, and cognitive symptoms. ALX-171 reversed DOI-induced head twitches and MK-801-induced disruptions of social interactions or cognition in the novel object recognition test and spatial delayed alternation test. On the other hand, the efficacy of the compound was not observed in the MK-801-induced hyperactivity test or prepulse inhibition. In summary, the observed antipsychotic activity profile of ALX-171 justifies the further development of the group of quinazolin-4-one derivatives in the search for a new drug candidate for schizophrenia treatment
It’s all in the crystals…
Protein surface engineering is increasingly used as a routine tool to enhance the crystallization propensity of proteins. Future possibilities include the use of multi-site protein variants, rational modulation of solubility and the development of strategies to tackle membrane proteins
A lightweight, flow-based toolkit for parallel and distributed bioinformatics pipelines
<p>Abstract</p> <p>Background</p> <p>Bioinformatic analyses typically proceed as chains of data-processing tasks. A pipeline, or 'workflow', is a well-defined protocol, with a specific structure defined by the topology of data-flow interdependencies, and a particular functionality arising from the data transformations applied at each step. In computer science, the dataflow programming (DFP) paradigm defines software systems constructed in this manner, as networks of message-passing components. Thus, bioinformatic workflows can be naturally mapped onto DFP concepts.</p> <p>Results</p> <p>To enable the flexible creation and execution of bioinformatics dataflows, we have written a modular framework for parallel pipelines in Python ('PaPy'). A PaPy workflow is created from re-usable components connected by data-pipes into a directed acyclic graph, which together define nested higher-order map functions. The successive functional transformations of input data are evaluated on flexibly pooled compute resources, either local or remote. Input items are processed in batches of adjustable size, all flowing one to tune the trade-off between parallelism and lazy-evaluation (memory consumption). An add-on module ('NuBio') facilitates the creation of bioinformatics workflows by providing domain specific data-containers (<it>e.g</it>., for biomolecular sequences, alignments, structures) and functionality (<it>e.g</it>., to parse/write standard file formats).</p> <p>Conclusions</p> <p>PaPy offers a modular framework for the creation and deployment of parallel and distributed data-processing workflows. Pipelines derive their functionality from user-written, data-coupled components, so PaPy also can be viewed as a lightweight toolkit for extensible, flow-based bioinformatics data-processing. The simplicity and flexibility of distributed PaPy pipelines may help users bridge the gap between traditional desktop/workstation and grid computing. PaPy is freely distributed as open-source Python code at <url>http://muralab.org/PaPy</url>, and includes extensive documentation and annotated usage examples.</p
Open problems on graph coloring for special graph classes.
For a given graph G and integer k, the Coloring problem is that of testing whether G has a k-coloring, that is, whether there exists a vertex mapping c:V→{1,2,…}c:V→{1,2,…} such that c(u)≠c(v)c(u)≠c(v) for every edge uv∈Euv∈E. We survey known results on the computational complexity of Coloring for graph classes that are hereditary or for which some graph parameter is bounded. We also consider coloring variants, such as precoloring extensions and list colorings and give some open problems in the area of on-line coloring
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Sulforaphane-enriched extracts from glucoraphanin-rich broccoli exert antimicrobial activity against gut pathogens in vitro and innovative cooking methods increase in vivo intestinal delivery of sulforaphane
Purpose
Studies on broccoli (Brassica oleracea var. italica) indicate beneficial effects against a range of chronic diseases, commonly attributed to their bioactive phytochemicals. Sulforaphane, the bioactive form of glucoraphanin, is formed by the action of the indigenous enzyme myrosinase. This study explored the role that digestion and cooking practices play in bioactivity and bioavailability, especially the rarely considered dose delivered to the colon.
Methods
The antimicrobial activity of sulforaphane extracts from raw, cooked super broccoli and cooked super broccoli plus mustard seeds (as a source myrosinase) was assessed. The persistence of broccoli phytochemicals in the upper gastrointestinal tract was analysed in the ileal fluid of 11 ileostomates fed, in a cross-over design, super broccoli soup prepared with and without mustard seeds.
Results
The raw super broccoli had no antimicrobial activity, except against Bacillus cereus, but cooked super broccoli (with and without mustard seeds) showed considerable antimicrobial activity against various tested pathogens. The recovery of sulforaphane in ileal fluids post soup consumption was < 1% but addition of mustard seeds increased colon-available sulforaphane 6-fold. However, when sulforaphane was extracted from the ileal fluid with the highest sulforaphane content and tested against Escherichia coli K12, no inhibitory effects were observed. Analysis of glucosinolates composition in ileal fluids revealed noticeable inter-individual differences, with six “responding” participants showing increases in glucosinolates after broccoli soup consumption.
Conclusions
Sulforaphane-rich broccoli extracts caused potent antimicrobial effects in vitro, and the consumption of sulforaphane-enriched broccoli soup may inhibit bacterial growth in the stomach and upper small intestine, but not in the terminal ileum or the colon
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