860 research outputs found

    Laser and microwave spectroscopy of even-parity Rydberg states of neutral ytterbium and Multichannel Quantum Defect Theory analysis

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    New measurements of high-lying even parity 6sns1 ⁣S06sns\, {}^1 \! S_0 and 6snd3,1 ⁣D26snd\,{}^{3,1}\!D_2 levels of neutral 174^{174}Yb are presented in this paper. Spectroscopy is performed by a two-step laser excitation from the ground state 4f146s21 ⁣S04f^{14}6s^2 \, {}^1 \! S_0, and the Rydberg levels are detected by using the field ionization method. Additional two-photon microwave spectroscopy is used to improve the relative energy accuracy where possible. The spectroscopic measurements are complemented by a multichannel quantum defect theory (MQDT) analysis for the J=0 and the two-coupled J=2 even parity series. We compare our results with the previous analysis of Aymar {\it{et al}} \cite{Aymar_1980} and analyze the observed differences. From the new MQDT models, a revised value for the first ionization limit I6s=50443.07041(25)I_{6s}=50443.07041(25) cm1^{-1} is proposed.Comment: 15 pages, 3 figure

    Multidisciplinary Conservative Treatment of Difficult Bile Duct Stones: A Real Alternative to Surgery

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    56 patients with large CBD or intrahepatic stones underwent endoscopic and/or percutaneous treatment followed by extracorporeal shock wave lithotripsy. Percutaneous access to the biliary tract was chosen when an endoscopic approach was not possible (hepaticojejunostomy in 5 patients, 1 juxtapapillary diverticulum and I inflammatory bile duct stricture). Visualization of stones was achieved radiologically in 32 patients and by ultrasound in 24. The procedure was successful in 47 of 56 treated patients (83.9%). Clearance of the biliary tract was obtained in 25 cases (53%), whereas in 22 cases (47%) complete clearing of biliary tract was obtained only after endoscopic extraction of fragments (17 cases) or percutaneous (5 cases). The median number of shock waves in each session was 1725 (range 300–3166), which were applied during one (n=30), two (n=22) or three sessions (n=4). The only complications were 1 case of symptomatic hyperamylasemia and 3 cases of macrohematuria. In conclusion, extracorporeal lithotripsy combined with endoscopic and/or percutaneous treatment is a real alternative to surgery for difficult stones

    Numerical Simulations of the 4D Edwards-Anderson Spin Glass with Binary Couplings

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    We present numerical results that allow a precise determination of the transition point and of the critical exponents of the 4D Edwards-Anderson Spin Glass with binary quenched random couplings. We show that the low T phase undergoes Replica Symmetry Breaking. We obtain results on large lattices, up to a volume V=104V=10^4: we use finite size scaling to show the relevance of our results in the infinite volume limit.Comment: 18 pages + 17 figures, revised bibliography and minor typos. Added Journal Re

    Impronta ambientale degli allevamenti montani di vacche da latte

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    L’obiettivo era quello dianalizzare l’impronta ambientale (metodo Life Cycle Assessment) della produzione di latte inallevamenti bovini delle Alpi orientali. Lo studio (Progetto TOPValue, Programma Interreg V-A Italia-Austria 2014-2020)ha coinvolto 75 aziende (38±25 UBA, 20.9±5.4 kg/vacca/ddi latte corretto per il tenore di proteina e grasso), per le quali sono stati raccolti dati circa la gestione degli animali e dei reflui, le produzioni agrarie e gli approvvigionamenti extra-aziendali. Gli indicatori di sostenibilità sono stati i seguenti: impronta del carbonio (CC, kg CO2-eq), del potenziale eutrofizzante (EP, g PO4-eq), per 1 kg di latte (1.2±0.2 kg CO2-eq e 6.0±1.7 g PO4-eq) e per 1 m2di superficie agraria (0.5±0.2 kg CO2-eq e 2.7±1.0 g PO4-eq), e l’efficienza di conversione dell’energia grezza degli alimenti potenzialmente edibilida parte dell’uomo (HeECR, MJ alimenti/MJ latte). Gli indicatori sono stati testati per l’effetto della classe di dimensione aziendale (3 classi) e per l’effetto dell’uso del pascolo per le vacche in produzione (presenza/assenza). L’effetto dimensionale non è risultato significativo per nessun indicatore. Le aziende con vacche in produzione al pascolo presentano valori simili di impatto (CC e EP) per 1 kg di latte, significativamente inferiori (P<0.01) per 1 m2e circa HeECR (-41%), rispetto le aziende con vacche in stalla tutto l’anno. I risultati mostrano come le aziende a gestione più tradizionale (aziende di piccola scala che utilizzano il pascolo) riescano a sfruttare in modo ottimale le risorse foraggere locali senza penalizzazioni circa la loro impronta ambientale

    Annotation of rule-based models with formal semantics to enable creation, analysis, reuse and visualization

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    Motivation: Biological systems are complex and challenging to model and therefore model reuse is highly desirable. To promote model reuse, models should include both information about the specifics of simulations and the underlying biology in the form of metadata. The availability of computationally tractable metadata is especially important for the effective automated interpretation and processing of models. Metadata are typically represented as machine-readable annotations which enhance programmatic access to information about models. Rule-based languages have emerged as a modelling framework to represent the complexity of biological systems. Annotation approaches have been widely used for reaction-based formalisms such as SBML. However, rule-based languages still lack a rich annotation framework to add semantic information, such as machine-readable descriptions, to the components of a model. Results: We present an annotation framework and guidelines for annotating rule-based models, encoded in the commonly used Kappa and BioNetGen languages. We adapt widely adopted annotation approaches to rule-based models. We initially propose a syntax to store machine-readable annotations and describe a mapping between rule-based modelling entities, such as agents and rules, and their annotations. We then describe an ontology to both annotate these models and capture the information contained therein, and demonstrate annotating these models using examples. Finally, we present a proof of concept tool for extracting annotations from a model that can be queried and analyzed in a uniform way. The uniform representation of the annotations can be used to facilitate the creation, analysis, reuse and visualization of rule-based models. Although examples are given, using specific implementations the proposed techniques can be applied to rule-based models in general

    Multi-site genetic analysis of diffusion images and voxelwise heritability analysis : a pilot project of the ENIGMA–DTI working group

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    The ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) Consortium was set up to analyze brain measures and genotypes from multiple sites across the world to improve the power to detect genetic variants that influence the brain. Diffusion tensor imaging (DTI) yields quantitative measures sensitive to brain development and degeneration, and some common genetic variants may be associated with white matter integrity or connectivity. DTI measures, such as the fractional anisotropy (FA) of water diffusion, may be useful for identifying genetic variants that influence brain microstructure. However, genome-wide association studies (GWAS) require large populations to obtain sufficient power to detect and replicate significant effects, motivating a multi-site consortium effort. As part of an ENIGMA–DTI working group, we analyzed high-resolution FA images from multiple imaging sites across North America, Australia, and Europe, to address the challenge of harmonizing imaging data collected at multiple sites. Four hundred images of healthy adults aged 18–85 from four sites were used to create a template and corresponding skeletonized FA image as a common reference space. Using twin and pedigree samples of different ethnicities, we used our common template to evaluate the heritability of tract-derived FA measures. We show that our template is reliable for integrating multiple datasets by combining results through meta-analysis and unifying the data through exploratory mega-analyses. Our results may help prioritize regions of the FA map that are consistently influenced by additive genetic factors for future genetic discovery studies. Protocols and templates are publicly available at (http://enigma.loni.ucla.edu/ongoing/dti-working-group/)

    Mapping tenascin-C interaction with toll-like receptor 4 reveals a new subset of endogenous inflammatory triggers

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    Pattern recognition underpins innate immunity; the accurate identification of danger, including infection, injury, or tumor, is key to an appropriately targeted immune response. Pathogen detection is increasingly well defined mechanistically, but the discrimination of endogenous inflammatory triggers remains unclear. Tenascin-C, a matrix protein induced upon tissue damage and expressed by tumors, activates toll-like receptor 4 (TLR4)-mediated sterile inflammation. Here we map three sites within tenascin-C that directly and cooperatively interact with TLR4. We also identify a conserved inflammatory epitope in related proteins from diverse families, and demonstrate that its presence targets molecules for TLR detection, while its absence enables escape of innate immune surveillance. These data reveal a unique molecular code that defines endogenous proteins as inflammatory stimuli by marking them for recognition by TLRs

    Imidazol-1-ylethylindazole Voltage-Gated Sodium Channel Ligands Are Neuroprotective during Optic Neuritis in a Mouse Model of Multiple Sclerosis

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    [Image: see text] A series of imidazol-1-ylethylindazole sodium channel ligands were developed and optimized for sodium channel inhibition and in vitro neuroprotective activity. The molecules exhibited displacement of a radiolabeled sodium channel ligand and selectivity for blockade of the inactivated state of cloned neuronal Na(v) channels. Metabolically stable analogue 6 was able to protect retinal ganglion cells during optic neuritis in a mouse model of multiple sclerosis

    Control of three-axis manipulator

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    Práca sa zaoberá riadením a presným polohovaním dopravníka v 3D priestore. Pre riadenie, polohovania bolo využité hardwarové a softvérové vybavenie od spoločnosti Bernecker&Reiner. Medzi ciele práce patrilo aj oboznámenie sa z programovacím prostredím AUTOMATION STUDIO, v ktorom prebiehala celá práca.This thesis deal swith controlling and precision positioning of conveyor in 3D space. Equipment for controling of positioning is made by Bernecker&Reinercompany. Important objective of work is also familiarization with programing environment AUTOMATION STUDIO, which powers whole operation.
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