829 research outputs found
SISAL: bringing added value to Speleothem research
Isotopic records from speleothems are an important source of information about past climates and, given the increase in the number of isotope-enabled climate models, are likely to become an important tool for climate model evaluation. SISAL (Speleothem Isotopes Synthesis and Analysis) have created a global database of isotopic records from speleothems in order to facilitate regional analyses and data-model comparison. The papers in this Special Issue showcase the use of the database for regional analyses. In this paper, we discuss some of the important issues underpinning the use of speleothems and how the existence of this database assists palaeoclimate research. We also highlight some of the lessons learned in the creation of the SISAL database and outline potential research going forward
EcografĂa del tracto gastrointestinal en pequeños animales
En el presente artĂculo se realiza una descripciĂłn de la imagen ecográfica normal del tracto digestivo en el perro y en el gato y de las diferentes patologĂas que pueden observarse
Trajectory Tracking Control of a Timed Event Graph with Specifications Defined by a P-time Event Graph
The aim of this paper is a trajectory tracking control of Timed Event Graphs with specifications defined by a P-time Event Graph. Two problems are solved on a fixed horizon knowing the current state: The optimal control for favorable past evolution; The prediction of the earliest future evolution of the process. These two parts make up an on-line control which is used on a sliding horizon. Completely defined in (max, +) algebra, the proposed approach is a Model Predictive Control using the componentwise order relation
Advanced and versatile interferometric technique for the characterization of photonic integrated devices
[EN] Adaptable and complex optical characterization of photonic integrated devices, permitting to unearth possible design and fabrication errors in the different workflow steps are highly desired in the community. Here, we propose a technique capable of resolving full optical amplitude and phase response, in both frequency and time domains, of a photonic integrated device. It relies on optical frequency domain interferometry and makes use of a novel integrated architecture; a 3-way interferometer enabling single input and single output detection. We derive the test structure design rules and provide extensive experimental validation in silicon nitride and silicon on insulator technologies, by testing relevant devices such as arrayed waveguide grating, Mach-Zehnder interferometers, and ring resonators. Horizontal and vertical chip coupling, different external setup arrangements, and the optical dispersion de-embedding inherent to the technique are demonstrated. Finally, we discuss why this characterization approach might lay the groundwork of a standard testing tool for photonic integrated devices.Ministerio de Economia y Competitividad (PTA2015-11309-I, TEC2015-69787-REDT PIC4TB, TEC201680385-P SINXPECT); Ministerio de Ciencia, Innovacion y Universidades (PID2019-110877GB-I00 BHYSINPICS); Generalitat Valenciana (GVA PROMETEO 2017/103).Bru-Orgiles, LA.; Pastor Abellán, D.; Muñoz, P. (2021). Advanced and versatile interferometric technique for the characterization of photonic integrated devices. Optics Express. 29(22):36503-36515. https://doi.org/10.1364/OE.435683S3650336515292
A parallel algorithm for the partial single-input pole assignment problem
AbstractFor a linear control system, we introduce a parallel algorithm to assign a desired subset of eigenvalues to a single-input linear invariant dynamic system. We obtain a sequential algorithm as a particular case. The proposed algorithms are conceptually simple and are based on the computation of left eigenvectors of the state matrix. In addition, the parallel algorithm parallelizes easily as the numerical examples show
Imagen ecográfica de la obstrucción biliar extrahepática en el perro : descripción de 7 casos
Se realizĂł un estudio ecográfico en siete perros que presentaban un cuadro de ictericia por obstrucciĂłn biliar extrahepática. Esta tĂ©cnica permitiĂł llegar al diagnĂłstico en seis de los casos. Se estudiĂł la imagen ecográfica de la dilataciĂłn de las vĂas biliares intra y extrahepáticas, asĂ como los signos asociados, tales como la presencia de una masa en el área pancreática, que pudiesen orientar sobre el origen de la obstrucciĂłn.An ultrasonographic examination was carried in out 7 dogs with icterus due to an extrahepatic biliary obstruction. This technique allowed the diagnosis in 6 of the dogs. The sonographic appearance of the dilated intra and extrahepatic biliary tree was assessed, as well as the associated lesions, such as the presence of a mass in the pancreatic area, which could guide towards the origin of the obstruction
Equilibrium states for the Bose gas
The generating functional of the cyclic representation of the CCR (Canonical
Commutation Relations) representation for the thermodynamic limit of the grand
canonical ensemble of the free Bose gas with attractive boundary conditions is
rigorously computed. We use it to study the condensate localization as a
function of the homothety point for the thermodynamic limit using a sequence of
growing convex containers. The Kac function is explicitly obtained proving
non-equivalence of ensembles in the condensate region in spite of the
condensate density being zero locally.Comment: 21 pages, no figure
Isolement d’une souche de bacille du rouget chez le chien
Bru C., Mondine P., Virat Bernard. Isolement d’une souche de bacille du rouget chez le chien. In: Bulletin de l'Académie Vétérinaire de France tome 128 n°9-10, 1975. pp. 453-456
A propos d’une toxi-infection d’origine carnée
Béchade A., Bru C., Gravière P. A propos d’une toxi-infection d’origine carnée. In: Bulletin de l'Académie Vétérinaire de France tome 116 n°2, 1963. pp. 83-89
Rational Design of Resveratrol O-methyltransferase for the Production of Pinostilbene
Pinostilbene is a monomethyl ether analog of the well-known nutraceutical resveratrol. Both compounds have health-promoting properties, but the latter undergoes rapid metabolization and has low bioavailability. O-methylation improves the stability and bioavailability of resveratrol. In plants, these reactions are performed by O-methyltransferases (OMTs). Few efficient OMTs that monomethylate resveratrol to yield pinostilbene have been described so far. Here, we report the engineering of a resveratrol OMT from Vitis vinifera (VvROMT), which has the highest catalytic efficiency in di-methylating resveratrol to yield pterostilbene. In the absence of a crystal structure, we constructed a three-dimensional protein model of VvROMT and identified four critical binding site residues by applying different in silico approaches. We performed point mutations in these positions generating W20A, F24A, F311A, and F318A variants, which greatly reduced resveratrol’s enzymatic conversion. Then, we rationally designed eight variants through comparison of the binding site residues with other stilbene OMTs. We successfully modified the native substrate selectivity of VvROMT. Variant L117F/F311W showed the highest conversion to pinostilbene, and variant L117F presented an overall increase in enzymatic activity. Our results suggest that VvROMT has potential for the tailor-made production of stilbenes.This research was funded by PROYECTO INTERDISCIPLINA-VRI-UC-II160020, number 3514-913, Pontificia Universidad Católica de Chile (to L.P.P. and A.S.) and BECA DE DOCTORADO NACIONAL 2016, number 21161084, National Agency for Research and Development (ANID), Chile (to D.P.H.), for which we are grateful. The APC was funded by Pontificia Universidad Católica de Chile
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