Surface solitons in two-dimensional quadratic photonic lattices

We study two-color surface solitons in two-dimensional photonic lattices with quadratic nonlinear response. We demonstrate that such parametrically coupled optical localized modes can exist in the corners or at the edges of a square photonic lattice, and we analyze the impact of the phase mismatch on their properties, stability, and the threshold power for their generation.Comment: 3 double-column pages,5 figures, submited to Optics Letter

Predictive factors for cesarean delivery : a retrospective study

Background: Cesarean section rates have risen markedly worldwide. Considering the potential harm caused by this mode of delivery, and the general concern in reducing its incidence, it would be useful to individualize the risk of non-planned cesareans, and if there is any possibility, reduce that risk, and anesthesiologists should take part of this risk evaluation. In recent studies, many factors have been related with a higher risk of cesarean, and controversy still surrounds labor analgesia impact on cesarean risk. The aim of this study was to search for predictive factors for nonplanned cesarean delivery. Methods: Retrospective analysis of all labors occurred in our Obstetric Department during 2014. Maternal related factors, previous obstetric history, birth weight and factors related to labor analgesia and labor progression were studied. Our primary outcome was cesarean delivery. Results: We identified two independent predictive factors for cesarean delivery: birth weight (p=0,007 OR= 1,001 CI 95% [1,0003; 1,002]) and labor length since beginning of analgesia (p<0,0001 OR= 1,00005 CI 95%[1,00003; 1,00007]). Searching correlation between registered variables, maternal body mass index was positively associated with newborn birth weight (p<0.0001, R=0.157). Conclusion: Our study showed that birth weight and labor length since beginning of epidural analgesia are independent predictor factors of non-planned cesarean delivery. Furthermore, birth weight was associated with maternal body mass index, providing health professionals a modifiable factor in which we can intervene to improve outcome. As labor progression to cesarean is of major obstetric and anesthetic concern, multidisciplinary initiatives are warranted to clearly identify important variables concurring to operative delivery.info:eu-repo/semantics/publishedVersio

XRD and FTIR analysis of Ti–Si–C–ON coatings for biomedical applications

Ti–Si–C–ON films were deposited by DC reactive magnetron sputtering using different partial pressure ratio of oxygen (pO2) and nitrogen (pN2). Compositional analysis revealed the existence of three different growth zones for the films; (I) N/Ti = 2.1 (high atomic ratio) and low oxygen content; (II) 0.76 < N/Ti < 2.1 (intermediate atomic ratio) and (III) N/Ti ≤ 0.12 (low ratio) and high oxygen content. For high N/Ti atomic ratio (N/Ti = 2.1) the XRD pattern exhibits reflections that correspond to a mixture of two different phases: a metallic-like Ti and a fcc NaCl type structure. Its electrical resistivity presents a metallic character and, consequently, has high infrared reflectivity. For the intermediate N/Ti ratio (0.76 < N/Ti < 2.1), the films crystallize in a B1-NaCl crystal structure typical for TiC0.2N0.8. Their FTIR spectra present C–N modes, besides the TiN ones, that indicate a progressive substitution of nitrogen by carbon atoms with increasing oxygen content (and lowering N/Ti ratio). For the highest oxygen content (and lower N/Ti ratio) the presence of the Ti–O–Ti stretching mode shows the formation of highly resistive Ti–O compounds consistent with the semiconductor character of this film. Biofilm formation as well as material cytotoxicity seemed to be related with the presence of the Ti

Structural and mechanical properties of Ti–Si–C–ON for biomedical applications

Ti–Si–C–ON films were deposited by DC reactive magnetron sputtering using different partial pressure of oxygen (pO2) and nitrogen (pN2) ratio. Compositional analysis revealed the existence of two different growth zones for the films; one zone deposited under low pO2/pN2 and another zone deposited under high pO2/pN2. The films produced under low pO2/pN2 were deposited at a lower rate and presented a fcc structure, as well as, dense and featureless morphologies. The films deposited with high pO2/pN2, consequently higher oxygen content, were deposited at a higher rate and developed an amorphous structure. The structural changes are consistent with the hardness and Young's modulus evolution, as seen by the significant reduction of the hardness and influence on the Young's modulus by increasing pO2/pN2

Biological properties of Ti-Si-C-O-N thin films

The main aim of this work was to study the feasibility of new coatings for medical devices. Ti-Si-C-O-N films were deposited by DC unbalanced reactive magnetron sputtering, using different oxygen and nitrogen partial pressure ratios (pO2/pN2). Surface properties were also analysed. Staphylococcus epidermidis was used to study biofilm formation and cytotoxicity was determined using fibroblasts. Surface morphology changed with the increase of pO2/pN2. Samples of high hydrophobicity displayed opposite behaviour in terms of biofilm formation, presenting the highest and lowest biomass. Moreover, the sample with the highest Ti content was the one, with the lowest biofilm amount, raising the possibility of a correlation between Ti and biofilm formation capability. In fact, this sample also displayed the highest degree of cytotoxicity (near 35%). This work shows the feasibility of the proposed coatings and highlights the importance of joining together both biological properties (biofilm formation and cytotoxicity) with the surface characterization

Propagation d'ondes dans des structures a GAP photonique : une comparaison entre calcul numerique et resultats experimentaux

Communication to : 'JCMM98', 5emes journees de caracterisation micro-onde et materiaux, Le Touquet (France), 13-15 mai 1998SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : 22419, issue : a.1998 n.63 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Application of the Beckman Model K automatic titrator to the potentiometric determination of uranium /

"ORNL-2031 ; Chemistry."Includes bibliographical references (p. 13).Operated by Union Carbide and Carbon CorporationMode of access: Internet