Search results for "Ven"
showing 10 items of 31764 documents
Phosphorous doping and drawing effects on the Raman spectroscopic properties of O=P bond in silica-based fiber and preform.
2012
International audience; We report an experimental study of the doping and drawing effects on the Raman activities of phosphorus (P)-doped silica-based optical fiber and its related preform. Our data reveal a high sensitivity level in the full width at half maximum value of the 1330 cm−1 (O = P) Raman band to the P-doping level. Its increase with the P doping level does not clash with an increase in the disorder of the O = P surrendering matrix. In addition, we observe that in the central core region of the sample (higher doping level), the drawing process decreases the relative band amplitude. We tentatively suggest that this phenomenon is due to the change in the first derivate of the bond…
Three-dimensional crystallization of the light-harvesting complex from Mantoniella squamata (Prasinophyceae) requires an adequate purification proced…
1995
Abstract We present a new purification procedure for the light-harvesting complex of Mantoniella squamata whereupon three-dimensional crystallization succeeded. Previous purification methods were based on density centrifugations as the only separating principle. We have extended this preparation procedure by applying anion-exchange and molecular-sieve chromatography techniques. Purity and stability of the complex were proved by denaturing and non-denaturing polyacrylamide-gel electrophoresis, and spectroscopic measurements. With respect to contaminating lipids the purified pigment-protein complex was examined by thin-layer chromatography and the aggregation and/or oligomeric states were inv…
Re: Technique of internal mammary dissection using pectoralis major flap to prevent contour deformities
2009
Economic Impact of 'Third-Wave' Cognitive Behavioral Therapies:A Systematic Review and Quality Assessment of Economic Evaluations in Randomized Contr…
2018
The term third-wave cognitive behavioral therapy (CBT) encompasses new forms of CBT that both extend and innovate within CBT. Most third-wave therapies have been subject to randomized controlled trials (RCTs) focused on clinical effectiveness; however, the number and quality of economic evaluations in these RCTs has been unknown and may be few. Evidence about efficiency of these therapies may help support decisions on efficient allocation of resources in health policies. The main aim of this study was to systematically review the economic impact of third-wave therapies in the treatment of patients with physical or mental conditions. We conducted a systematic literature search in PubMed, Psy…
Radiological Assessment of Pediatric Scoliosis Patients
2021
Nosaukums: Radioloģiskais izmeklējums pediatriskiem pacientiem ar skoliozi Autore: Saara Anni Susanna Suomalainen, medicīnas studente Darba vadītājs: Dr. med. Paulis Laizāns un Dr. med. Jānis Upenieks Priekšvēsture : Skolioze ir sānu novirze, kas pārsniedz 10 grādus no normāla mugurkaula, mērot pēc rentgenogrammas, un tāpēc, ka sānu līkne ir saistīta ar skriemeļu rotāciju līknes iekšienē, rodas trīsdimensiju deformācija. Idiopātiskā skolioze bērnu populācijā ir sadalīta trīs vecuma grupās - zīdaiņu, bērnu un pusaudžu. Radiogrāfiskais novērtējums ir galīgās diagnozes pīlārs. Labi uzņemtos rentgenogrammās var novērtēt segmentācijas anomāliju raksturojumu, izliekumu veidu un to elastību, kā ar…
Color Sensitive Response of Graphene/Graphene Quantum Dot Phototransistors
2019
We present the fabrication and characterization of all-carbon phototransistors made of graphene three terminal devices, coated with atomically precise graphene quantum dots (GQD). Chemically synthesized GQDs are the light absorbing materials, while the underlying chemical vapor deposition (CVD)-grown graphene layer acts as the charge transporting channel. We investigated three types of GQDs with different sizes and edge structures, having distinct and characteristic optical absorption in the UV–vis range. The photoresponsivity exceeds 106 A/W for vanishingly small incident power (<10–12 W), comparing well with state of the art sensitized graphene photodetectors. More importantly, the photor…
La palabra en las maternidades: una aproximación a la psicología perinatal
2001
El reconocimiento del recién nacido como un ser interactuante con el medio físico y humano que lo rodea, implicó cambios en las conductas de los equipos de salud , a cargo de las unidades de internación neonatal. Los conceptos de interacciones precoces, de apego, de díada, de vulnerabilidad maternal, competencias conductuales del recien nacido, y su utilización reciente en el desarrollo de la psicología perinatal, marcaron una transformación en el enfoque de los distintos profesionales involucrados en el proceso del nacimiento. Por un lado, podemos decir que la medicalización del acto del nacimiento en la sociedad occidental ha permitido disminuír el riesgo morbi-mortalidad matern…
Revisionismo histórico y racismo en la jurisprudencia constitucional : los límites de la libertad de expresión (a propósito de la STC 235/2007)
2007
Después de plantear la contradicción existente en la jurisprudenciaconstitucional que, por una parte, admite el revisionismo histórico conel límite del respeto a la dignidad y, por otra parte, reconoce con lamáxima amplitud la libertad ideológica, se analiza la STC 235/2007que ha declarado inconstitucional el delito de negación del genocidioy, en cambio, ha considerado constitucional la penalización de la justificacióndel genocidio. Esta sentencia ha clarificado parcialmente lasituación del revisionismo histórico y, en general, de la difusión de ideascontrarias a la Constitución pero sigue existiendo aquella contradicción;no obstante, ha aportado elementos como la distinción entreideas y ac…
Spin filtering by proximity effects at hybridized interfaces in spin-valves with 2D graphene barriers
2020
We report on spin transport in state-of-the-art epitaxial monolayer graphene based 2D-magnetic tunnel junctions (2D-MTJs). In our measurements, supported by ab-initio calculations, the strength of interaction between ferromagnetic electrodes and graphene monolayers is shown to fundamentally control the resulting spin signal. In particular, by switching the graphene/ferromagnet interaction, spin transport reveals magneto-resistance signal MR > 80% in junctions with low resistance × area products. Descriptions based only on a simple K-point filtering picture (i.e. MR increase with the number of layers) are not sufficient to predict the behavior of our devices. We emphasize that hybridization …
Adjacency matrices of random digraphs: singularity and anti-concentration
2017
Let ${\mathcal D}_{n,d}$ be the set of all $d$-regular directed graphs on $n$ vertices. Let $G$ be a graph chosen uniformly at random from ${\mathcal D}_{n,d}$ and $M$ be its adjacency matrix. We show that $M$ is invertible with probability at least $1-C\ln^{3} d/\sqrt{d}$ for $C\leq d\leq cn/\ln^2 n$, where $c, C$ are positive absolute constants. To this end, we establish a few properties of $d$-regular directed graphs. One of them, a Littlewood-Offord type anti-concentration property, is of independent interest. Let $J$ be a subset of vertices of $G$ with $|J|\approx n/d$. Let $\delta_i$ be the indicator of the event that the vertex $i$ is connected to $J$ and define $\delta = (\delta_1, …