45 research outputs found
Study and analysis of an electric Z-shaped meta-atom
A printed Z-shaped electric meta-atom is presented as an alternative design to the conventional electric-LC (ELC) resonator. We propose to redesign the ELC resonator pattern to get a compact and a low cost electric resonator exhibiting a strong electric response. Our approach consists in redressing the resonator shape to accommodate higher inductance and therefore leading to a lower resonance frequency without being limited by fabrication tolerances. Simulation and measurement results show that the Z metaatom exhibits an electric response to normally incident radiation and can be used very effectively in producing materials with negative permittivity
Benign osteoblastoma in an unusual mastoid location
SummaryIntroductionBenign osteoblastoma (OB) is an unusual primary bone tumor. The preferred locations are the posterior arch of vertebrae and long bones. We report herein an extremely rare location of an OB in the mastoid process of the temporal bone.Case reportA 22-year-old woman presented with painful left retro-auricular swelling. Computed tomography features were suggestive of an aggressive osteolytic lesion of the left mastoid. The pathologic examination of bone curettage material revealed a benign OB. A complete resection of the tumor was performed later, with no evidence of recurrence at 1 year.Discussion/ConclusionTo our knowledge, this is the 14th reported case of OB confined to the mastoid process of temporal bone. Its histological diagnosis can be difficult and osteosarcoma is its principal differential diagnosis. Although generally regarded as benign, OB has potential for recurrence and local invasion. As such, complete resection, whenever possible, is preferred over conventional curettage
Screening of antioxidant potentials and bioactive properties of the extracts obtained from two Centaurea L. species (C. kroumirensis coss. and C. sicula L. subsp sicula)
Herbal medicines, dietary supplements, or infusions with health promoting effects can note strong consumer demand. Hence, researchers and scientists have been increasingly focusing on the promotion of medicinal plants. In this respect, the present study has the evaluation of the biological properties of different extracts (hexane, chloroform, methanol, ultrasonic, essential oil, and supercritical) obtained from two Centaurea species (C. kroumirensis (Coss.) and C. sicula L. subsp sicula) as purpose. Antioxidative activities were assessed by in vitro assays including total phenolic content, free radical scavenging assay and ferric ion reducing power. Among the fourteen extracts examined, the highest total phenolic content (TPC) and antioxidant abilities were recorded in ultrasonic ethanol extracts of both Centaurea species. Additionally, these extracts exhibited a noticeable strong protective effect of the human skin fibroblast cell line (HS-68) that was exposed to oxidative stress induced by hydrogen peroxide. According to our results, the sonication with ethanol might be an ideal, rapid, and eco-friendly extraction method for obtaining a polyphenol-rich extract that exhibited high antioxidant activity. The results presented herein suggest that Centaurea species could be promoted as an antioxidant resource that could be exploited for the development of nutraceuticals or in pharmacology industry
Study and analysis of an electric Z-shaped meta-atom
A printed Z-shaped electric meta-atom is presented as an alternative design to the conventional electric-LC (ELC) resonator. We propose to redesign the ELC resonator pattern to get a compact and a low cost electric resonator exhibiting a strong electric response. Our approach consists in redressing the resonator shape to accommodate higher inductance and therefore leading to a lower resonance frequency without being limited by fabrication tolerances. Simulation and measurement results show that the Z metaatom exhibits an electric response to normally incident radiation and can be used very effectively in producing materials with negative permittivity
Usefulness of molecular biology performed with formaldehyde-fixed paraffin embedded tissue for the diagnosis of combined pulmonary invasive mucormycosis and aspergillosis in an immunocompromised patient
Immunocompromised patients who develop invasive filamentous mycotic infections can be efficiently treated if rapid identification of the causative fungus is obtained. We report a case of fatal necrotic pneumonia caused by combined pulmonary invasive mucormycosis and aspergillosis in a 66 year-old renal transplant recipient. Aspergillus was first identified during the course of the disease by cytological examination and culture (A. fumigatus) of bronchoalveolar fluid. Hyphae of Mucorales (Rhizopus microsporus) were subsequently identified by culture of a tissue specimen taken from the left inferior pulmonary lobe, which was surgically resected two days before the patient died. Histological analysis of the lung parenchyma showed the association of two different filamentous mycoses for which the morphological features were evocative of aspergillosis and mucormycosis. However, the definitive identification of the associative infection was made by polymerase chain reaction (PCR) performed on deparaffinized tissue sections using specific primers for aspergillosis and mucormycosis. This case demonstrates that discrepancies between histological, cytological and mycological analyses can occur in cases of combined mycotic infection. In this regard, it shows that PCR on selected paraffin blocks is a very powerful method for making or confirming the association of different filamentous mycoses and that this method should be made available to pathology laboratories
Inductive-varying grid for highly beam-steerable cavity antennas
International audienceThe design of a locally one-dimensional inductive-varying metamaterial operating near 10 GHz is reported. This is combined with a fixed capacitive grid to design a phase-varying metasurface. This composite metasurface is then used as a partially reflecting surface (PRS) together with a perfect electric conductor surface to form a resonant Fabry-Perot type cavity. A patch antenna acting as a primary source is embedded in the cavity to constitute a highly beam-steerable directive antenna. A 56 degrees deflection of the antenna beam is experimentally observed
Interpretation of the electric resonance in Z-shaped meta-atom
7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), Bordeaux, FRANCE, SEP 16-19, 2013International audienceA planar Z-shaped meta-atom has been recently proposed as an alternative design to the conventional electric-LC (ELC) resonator for achieving negative permittivity. Transforming the LC topology of the resonator helps to facilitate transposition of geometrical parameters for the optical regime and also to improve the metamaterial homogeneity. In this work, we discuss about the interpretation of the resonance in such Z-shaped meta-atom
Analysis of a subwavelength Z-shaped metamaterial
A Z-shaped easy made planar meta-atom is presented as an alternative design to the conventional electric-LC (ELC) resonator for achieving negative permittivity. Transforming the LC topology of the..
Interpretation of the electric resonance in Z-shaped meta-atom
7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS), Bordeaux, FRANCE, SEP 16-19, 2013International audienceA planar Z-shaped meta-atom has been recently proposed as an alternative design to the conventional electric-LC (ELC) resonator for achieving negative permittivity. Transforming the LC topology of the resonator helps to facilitate transposition of geometrical parameters for the optical regime and also to improve the metamaterial homogeneity. In this work, we discuss about the interpretation of the resonance in such Z-shaped meta-atom