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This paper presents a new design of dual-pole (4-pole and 8-pole) Line Start Synchronous Motor (LSSM) with consequent magnetic pole structure. The proposed structure reduces the Permanent Magnet (PM) volume in the rotor core by 67 percent with respect to the reference dual-pole machine. Given the direct impact of the PM magnetic field on producing negative torque components such as braking torque and pulsating torque, lower PM volume can potentially limit the production of such negative torques. Therefore, in addition to cost saving benefits, the proposed structure contributes to a smooth start-up process. Meanwhile, different geometrical structures of PMs and flux barriers are discussed, their impacts on the overall motor performance are highlighted, and general design guidelines are provided. In particular, six different rotor structures with different PM arrangement and/or flux barrier arc angle are analyzed in Finite Element (FE) and their steady-state and transient performance metrics are compared. Finally, the best motor candidate is selected for further analyses, and prototyping.

Background: Simultaneous ipsilateral floating knee and hip is a very rare injury and so far, no standard guideline has been determined for its treatment. Case Report:In the current study, we report a surgical technique for the treatment of a 17-year-old patient with this condition on his left side. Conclusion: We recommend to start the fixation from proximal and stabilize the pelvic ring at first, then fix the posterior part of the acetabulum and femoral shaft with the same posterior approach.

Background: Choosing the proper approach to surgical treatment of various types of acetabular fractures can play an important role in minimizing adverse outcomes during and after surgery. In the present study, we described our experience on the outcome of Stoppa approach in anterior column acetabular fractures. Methods: This was a retrospective analysis of 40 patients with acetabular anterior column fractures that had undergone surgery with Stoppa approach. The study information, Harris Hip Score (HHS), and pre- and post-operative radiographic findings were collected by reviewing the hospital recorded files. Results: HHSs of 80 to 100 were achieved in 75.0% of patients. Completed (anatomic reduction less than 2 mm) displacement reduction was found in 97.5%. 2 mg/dl decreased serum level of hemoglobin (Hb) was found in 75.0%, leading to blood transfusion in 60% of subjects. Regarding post-procedural complications, the common event was infection in 15.0%, followed by degenerative joint disease (DJD) in 15.0%. The post-operative complications were similar in men and women, but were significantly higher in patientsolder than 50 years than the younger patients. Conclusion: Stoppa approach is associated with high success rate and the occurrence of rare and tolerable major complications.

We investigated the feasibility of using platinum nanostructures to accomplish the metal-enhanced fluorescence (MEF) in the UV spectral region. We examine the possibility for detection of the intrinsic fluorescence from nucleotides and G-quadruplex DNA on platinum nanoparticles. Guanosine monophosphate (GMP) showed significant increases (similar to 20-fold) in fluorescence intensities in the presence of platinum nanostructures when compared to quartz controls. G-quadruplex DNA demonstrated similar to 5-fold increase in fluorescence intensity and higher photostability in the presence of Pt nanostructures. We performed Finite Element Method simulations to explore how Pt nanoparticles interact with plane waves and conformed that the Pt nanostructures are promising for enhancing the fluorescence emission in the UV region. (C) 2012 Elsevier B. V. All rights reserved.

Multilayer substrates consisting of a glass slide, silver mirror, silica layer, and silver nanoparticles were fabricated using magnetron sputtering. This new geometry of substrates with backplane mirror and dielectric photonic cavity produced large average fluorescence enhancements up to 190-fold. Fluorescence enhancements of five fluorescent probes were measured over the broad spectral range from 470 to 800 nm. Fluorescent probes were streptavidin conjugates attached to the substrate surface through a layer of biotinylated bovine serum albumin. The protein layers represent a common surface modification for surface-based bioassays such as immunoassays or molecular diagnostic assays. We found that optimal enhancement is dependent on the thickness of the dielectric layer separating the silver mirror and the silver nanoparticles and on the spectral range. We performed numerical calculations for enhancement in both the excitation and emission using finite element method (FEM) the results of which were in qualitative agreement with the experimental results. The described method for fabrication multilayered substrates and the results obtained with protein layers demonstrate great potential for the design of simple and ultrasensitive fluorometric bioassays with large optical amplifications compared to the standard approaches of enzyme-based bioassays with dielectric surfaces.

We study fluorescence excitation and emission enhancement in the ultraviolet regime for molecules confined within sub-wavelength metal apertures. Calculations are performed across a range of excitation wavelengths for individual apertures constructed in gold, silver, and aluminum. As expected, enhancement in the ultraviolet is greatest with aluminum. Using excitation and emission wavelengths appropriate for tryptophan, we find that more than 10× net increase in fluorescence count rate should be obtainable for aluminum apertures of ~75 nm diameter. These results suggest that many applications utilizing native protein fluorescence could become practical, even to the single molecule level.

We study the excitation and emission enhancement mechanisms for fluorescence from molecules confined within subwavelength metal apertures, or nanocavities. The variation in these enhancements with wavelength is calculated for individual round nanocavities in gold of varying diameters and dielectric environments. Enhancement peaks are associated with localized surface plasmon resonances of the nanocavity. In addition, these enhancements strongly vary with location within the nanocavity. These results should aid future work in maximizing overall fluorescence enhancement from these structures.

We studied fluorescence enhancement of molecular species bound within metallic nanocavities. These nanostructures possess a number of desirable properties for real-time microarrays, such as localization of excitation light within the nanocavities, strong isolation from fluorescence produced by unbound species, and an apparent increase in fluorescence yield for bound species. Experimental measurements show nearly a factor of two increase in excitation intensity within the nanocavities, and factor of six increase in yield. A simple electromagnetic model of a dipole within a nanocavity shows an increase in radiative output consistent with our yield estimates, and also verifies the strong fluorescence isolation from species lying outside the nanocavity.

In this article, we reported the near-field interactions between the Ru(bpy)(3) (2+) complexes and plasmon resonances from the bimetallic nanoshells. The metallic nanoshells were fabricated on 20 nm silica spheres as cores by depositing 10 nm monometallic or bimetallic shells. There were approx. 15 Ru(bpy)(3) (2+) complexes in the silica core. The metal shells were constituted of silver or/and gold. The bimetallic shells could be generated in homogeneous or heterogeneous geometries. The homogeneous bimetallic shells contained 10 nm silver-gold alloys. The heterogeneous bimetallic shells contained successive 5 nm gold and 5 nm silver shells, or alternatively, 5 nm silver and 5 nm gold shells. Optical properties of metal nanoshells were studied on both the ensemble spectra and single nanoparticle imaging measurements. The heterogeneous bimetallic shells were found to have a large scale of metal-enhanced emission relative to the monometallic or homogeneous bimetallic shells. It is because the heterogeneous bimetallic shells may display split dual plasmon resonances which can interact with the excitation and emission bands of the Ru(bpy)(3) (2+) complexes in the silica cores leading to more efficient near-field interactions. The prediction can be demonstrated by the lifetimes. Therefore, it is suggested that both the compositions and geometries of the metal shells can influence the interactions with the fluorophores in the cores. This observation also offers us an opportunity for developing plasmon-based fluorescence metal nanoparticles as novel nanoparticle imaging agents which have high performances in fluorescence cell or tissue imaging.

Arbuscular mycorrhizal (AM) fungi are known to be well distributed throughout both hemispheres. These fungi can be isolated from a wide variety of natural habitats and are particularly abundant in cultivated lands. Little work has been carried out regarding their distribution in grapevine fields in Iran especially in west Azerbaijan as important producing area. During the periods from July to September 2008 to 2009, 40 composite soil samples were collected from 4 main vineyard growing sites in west Azerbaijan province of Iran. The spore numbers as well as identification and distribution of fungal species were studied. The number of spores varied between 32 to 695 spores with an average of 213 spores per 100 g soil sample. After root clearing and staining, fungal colonization as well as different fungal structures including fungal hyphae, vesicles and arbuscules could be observed. Cluster analysis of sampling habitats based on average spore numbers using UPGMA (unweighted pair group method with arithmetic mean) method showed that habitats put in 2 main clusters. Habitats A, B and C put in one cluster and habitat D put in separate one. Among the 12 fungal species identified, 11 species were of Glomus and 1 species belonged to Scutellospora genera. The most and least abundant species recorded were Glomus fasciculatum and Glomus glomerulatum with a frequency of 78 and 1%, respectively. Keywords: Arbuscular mycorrhiza fungi, identification, diversity, grapevine.

A nanoscale layer of chromium or titanium is commonly used in plasmonic nanoantennas to firmly adhere a gold film to a glass substrate, yet the influence of this layer on the antenna performance is often ignored. As a result, the need for the use of potentially better materials is not widely recognized. Using a single aperture milled in a gold film with 120 nm diameter as a nanobench for these investigations, we present the first experimental report of the strong dependence of the plasmonic enhancement of single-molecule fluorescence on the nature of the adhesion layer. By combining fluorescence correlation spectroscopy and fluorescence lifetime measurements, we show that this structure is very sensitive to the properties of the adhesion layer, and we detail the respective contributions of excitation and emission gains to the observed enhanced fluorescence. Any increase in the absorption losses due to the adhesion layer permittivity or thickness is shown to lower the gains in both excitation and emission, which we relate to a damping of the energy coupling at the nanoaperture. With this nanobench, we demonstrate the largest enhancement factor reported to date (25×) by using a TiO(2) adhesion layer. The experimental data are supported by numerical simulations and argue for a careful consideration of the adhesion layer while designing nanoantennas for high-efficiency single-molecule analysis.

A bare nanometric aperture milled in a metallic film forms a simple nanophotonic device that can strongly enhance the optical properties of nearby emitters such as fluorescent molecules. In this paper, we experimentally and numerically compare the properties of circular apertures milled in gold and aluminum, and discuss the influence of a noble metal holding plasmonic resonances in the visible range such as gold. We report that nanometric apertures milled in gold exhibit significantly higher fluorescence enhancement factors than apertures in aluminum. We relate this effect to a larger enhancement of the excitation intensity and radiative rate for an aperture milled in gold. A spectrally resolved analysis of the fluorescence emission from apertures is also presented. Comparison with numerical simulations shows that the enhancement factor is maximum when the photonic density of modes is maximum. Altogether, these results provide crucial knowledge for the design of nanoapertures towards high-efficiency single-molecule analysis.