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An approach which allows both electrochemical studies and surface enhanced infrared characterization of electrodeposited Cytochrome C is presented. This approach is based on in-plane disordered arrays of resonant slits engraved in Au substrates using focused ion beam. For light-polarized perpendicular to the slit, the reflectivity spectra of the slit arrays show dips related to the excitation of the slit plasmon resonance, whose position depends on the slit length. Due to the presence of the continuous Au layer around the slits, the very same substrates can be used to perform electrochemical studies. By varying the slit length, we have tuned the plasmon resonance to match the absorption bands of electrodeposited Cytochrome C, demonstrating the detection of minute amounts of this protein, all the way down to a single monolayer. [ABSTRACT FROM AUTHOR]

We analyze the optical and chirooptical response of two Au nanorods vertically separated and with arbitrary relative in-plane orientation. The use of a simple model of Lorentzian oscillators assigned to the resonances of each individual rod allows analyzing the evolution of the optical properties of this 3D chiral system as a function of relative in-plane orientation, inter-rod separation, and rod dimensions. These results are compared with real physical structures fabricated by multiaxial thermal evaporation through nanohole masks. Despite the simplicity of the theoretical model, the obtained results reproduce the main experimental optical properties of the rod system. [ABSTRACT FROM AUTHOR]

We present a morphological, structural, and magnetic characterization of Co nanoparticles (mean diameter of 10.3 ± 1.8 nm) grown using a gas aggregation source and embedded in a silicon oxide matrix by sequential deposition of nanoparticles and silicon oxide. We show that the Co nanoparticles 'soft-land' on the substrates and suffer a moderate oxidation in contact with the silicon oxide. Despite this moderate oxidation, it is found that, at room temperature, the magnetic volume of the resulting nanoparticles is below the superparamagnetic limit. The results presented in this article are compatible with the presence of an assembly of magnetically independent particles that also display a moderate exchange bias at low temperature. [ABSTRACT FROM AUTHOR]

The optical and magneto-optical properties of hybrid Co-SiO systems are studied as a function of Co concentration. The structures were prepared by alternate depositions of SiO thin films and layers of 10-nm-diameter Co nanoparticles produced by an Ion Cluster Source. Both optical and magneto-optical constants of the system gradually increase with the amount of Co, though maintaining low optical absorption values in the visible range. The experimental results are well reproduced assuming that the nanoparticles have a cobalt core (7-8 nm in diameter) surrounded by a cobalt oxide shell (1-2 nm thick). The magneto-optical activity versus optical absorption figure of merit of this system is compared with other magneto-optical dielectric systems. [ABSTRACT FROM AUTHOR]

Surface-plasmon-mediated confinement of optical fields holds great promise for on-chip miniaturization of all-optical circuits. Following successful demonstrations of passive nanoplasmonic devices, active plasmonic systems have been designed to control plasmon propagation. This goal has been achieved either by coupling plasmons to optically active materials or by making use of transient optical nonlinearities in metals via strong excitation with ultrashort laser pulses. Here, we present a new concept in which the active optical component is a metal–ferromagnet–metal structure. It is based on active magneto-plasmonic microinterferometry, where the surface plasmon wave vector in a gold–ferromagnet–gold trilayer system is controlled using a weak external magnetic field. Application of this new technique allows measurement of the electromagnetic field distribution inside a metal at optical frequencies and with nanometre depth resolution. Significant modulation depth combined with possible all-optical magnetization reversal induced by femtosecond light pulses opens a route to ultrafast magneto-plasmonic switching. [ABSTRACT FROM AUTHOR]

Background: The use of fibrin for mesh fixation in laparascopic hernioplasty has theoretical advantages in that it could result in reducing postoperative pain. The objective of this study is to demonstrate this improvement in postoperative pain with the highest level of evidence possible.Methods: Unicenter single surgeon prospective randomized double-blind study of transabdominal preperitoneal (TAPP) bilateral hernioplasties comparing autologous fibrin sealant (FG) used for mesh fixation on one side and staples (SG) on the other. Data were collected regarding anthropometric measures, costs, complications and pain evaluation at postoperative days 7, 30 and 180 using a visual analogue scale. The patients were also asked to answer the following simple question: "On which side do you have more pain?"Results: Twenty-two eligible patients were included in the study. Both groups were comparable. The operating time was significantly longer (30 min more) in the FG. The incidence of seroma was similar in both groups, and that of hematoma was higher in the SG (0 vs. 9.1%). At 1 week, the visual analogue scale scores were significantly lower in the FG (median: 1.7 vs. 4.5; MWU:103.5, p < 0.05). At 1 month, this difference became clinical and statistically insignificant. 72.7% of the patients referred more pain on the side with staples at 1 week, 38% at 1 month, and 0% at 6 months (after patients with hernia recurrence were excluded). The recurrence rate was higher in the FG (9.9 vs. 13.6%). A hernia in the FG cost 200 Euros more than that in the SG, or even more if a complete economic study is considered.Conclusions: The use of fibrin produces less postoperative pain in the first week, but prolongs operating time and increases costs. Moreover, there appears to be a higher recurrence rate and a lower incidence of hematoma, while the incidence of seroma remains unchanged. [ABSTRACT FROM AUTHOR]

Background: The incidence of trocar site hernia (TSH) after laparoscopic ventral hernia repair (LVHR) is reported to be low. The present study investigates the associated risk factors, with a view to preventing this complication.Methods: A retrospective study was made of the incidence of TSH in a personal series of LVHR, recording anthropometric and clinical data on the patients. Risk factors were assessed by bivariate and multivariate analyses. The patients were subjected to clinical and telephone follow-up.Results: In a series of 27 LVHR, the incidence of TSH was 22% (6 patients). The use of meshes larger than 10 x 15 cm for LVHR was the only TSH risk factor to reach statistical significance. Female gender and diabetes showed a higher incidence in the TSH group.Conclusions: The use of large meshes may be a risk factor for TSH. We believe this to be due to dilatation of the trocar orifice during introduction of the mesh, and also to postoperative retraction of the mesh. [ABSTRACT FROM AUTHOR]