A Broadband UHF Tag Antenna For Near-Field and Far-Field RFID Communications

The paper deals with the design of passive broadband tag antenna for Ultra-High Frequency (UHF) band. The antenna is intended for both near and far fields Radio Frequency Identification (RFID) applications. The meander dipole tag antenna geometry modification is designed for frequency bandwidth increasing. The measured bandwidth of the proposed broadband Tag antenna is more than 140 MHz (820–960 MHz), which can cover the entire UHF RFID band. A comparison between chip impedance of datasheet and the measured chip impedance has been used in our simulations. The proposed progressive meandered antenna structure, with an overall size of 77 mm × 14 mm × 0.787 mm, produces strong and uniform magnetic field distribution in the near-field zone. The antenna impedance is matched to common UHF chips in market simply by tuning its capacitive and inductive values since a perfect matching is required in the antenna design in order to enhance the near and the far field communications. Measurements confirm that the designed antenna exhibits good performance of Tag identification for both near-field and far-field UHF RFID applications

Chemical composition, antibacterial and antioxidant activities of essential oils from flowers, leaves and aerial parts of Tunisian Dittrichia Viscosa

The objective of this work was to determine the chemical composition, the antioxidant and antibacterial activities of the essential oils (EOs) extracted by hydrodistillation from different organs of the D. viscosa: flowers, leaves and aerial parts. The main compounds identified by GC/MS are oxygenated sesquiterpenes. Among these compounds, (E)-nerolidol (40.7%) is the most abundant constituent of flowers’ essential oil while caryophyllene oxide (9.9%), isolongifolan-7-α-ol (10.3%) and α -eudesmol (9.1%) are the major constituents of the leaves’ essential oil. The presence of these compounds in the aerial parts’ essential oil is solely due to those of the flowers and leaves that constitute these aerial parts. The volatile extracts showed antioxidant effects with IC50 values ranging between 9.25 and 9.75 mg.mL−1. On the other hand, EOs showed antibacterial effects on both Gram-positive and Gram-negative bacteria. The highest activity was obtained with flowers’ essential oil against Enterococcus faecalis and Escherichia coli

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

Adsorption of emerging pollutants on lignin-based activated carbon: Analysis of adsorption mechanism via characterization, kinetics and equilibrium studies

Lignin has been employed as a precursor to synthesize activated carbons with the aim of lignin-biomass revalorization. The properties of these activated carbons were compared, and the best adsorbent was employed to remove two emerging pollutants from water, acetaminophen and acetamiprid. The adsorption mechanisms of pharmaceutical and pesticide compounds were analyzed, modeled and interpreted via statistical physics models. In particular, adsorption kinetics and isotherms of acetaminophen and acetamiprid at temperatures between 20 and 60 ◦C were quantified experimentally. Equilibrium data were fitted to different statistical physics-based isotherm models to establish the corresponding adsorption mechanism. A double layer adsorption model with one type of functional group was the best to correlate and explain the removal of these organic molecules. Steric parameters for the adsorption of these organic compounds were also calculated thus determining that their adsorption was multi-molecular. At tested operating conditions, acetaminophen adsorption was endothermic, while acetamiprid removal was exothermic. Physical adsorption forces were expected to be responsible for the removal of both compounds. This study reports new insights on the adsorption mechanisms of relevant emerging pollutants commonly found in water worldwid

Diagnostic et prise en charge de l’hyperparathyroïdie primaire

Objectif : L’hyperparathyroïdie primaire (hPTP) est définie par la production excessive et inappropriée de parathormone (PTh). Les formes asymptomatiques et modérées sont devenues de plus en plus fréquentes. Le but de ce travail est d’étudier les caractéristiques cliniques et paracliniques de l’hPTP, de préciser les indications thérapeutiques et de les discuter en comparant nos résultats avec ceux de la littérature.Matériel et méthodes: Il s’agit d’une étude rétrospective à propos de 86 patients colligés entre Janvier 2005 et Décembre 2010. Tous les patients ont bénéficié d’un examen ORL et d’un bilan biologique comportant une calcémie et un dosage de la PTh. Le bilan radiologique comportait une échographie cervicale, une scintigraphie au MIBI et/ou une IRM cervicale.Tous les patients ont été opérés sous anesthésie générale et ont eu une cervicotomie par approche classique. La surveillance a été clinique et biologique avec un recul moyen de 16 mois (4-36 mois).Résultats : La calcémie était élevée chez 77 patients (89,5%) et la PTh chez tous les patients. Une échographie cervicale a été réalisée chez 79 patients et a montré une image en faveur d’un adénome parathyroïdien chez 37 d’entre eux (46,8%). La scintigraphie au MIBI, pratiquée chez 46 patients, a montré une hyperfixation dans 31 cas (67,4%). L’IRM aété pratiquée chez 5 patients et a révélé un adénome dans 3 cas.L’exploration chirurgicale avec examen extemporané a révélé un adénome unique chez 65 patients deux adénomes chez 12 patients, et une hypertrophie des 4 PTh chez 9 autres. Une exérèse des adénomes a été ainsi réalisée chez 77 patients et une parathyroïdectomie subtotale dans 9 cas. en post-opératoire, 12 patients (14%) ont présenté une hypocalcémietransitoire. Aucune hypocalcémie définitive ni paralysie récurrentielle n’ont été notées. L’examen anatomopathologique définitif a révélé un adénome unique, un adénome double, une hyperplasie et PTh normale respectivement chez 58, 3, 24 et 1 patients. L’évolution à long terme a été marquée par l’amélioration clinique et biologique chez 81 patients  (94,2%). Une non-amélioration clinique et biologique a été notée chez 5 patients. Ils ont été réopérés et ont eu une parathyroïdectomie subtotale. L’anatomopathologie confirmait l’hyperplasie dans tous les cas.Conclusion : Le traitement de l’hPTP symptomatique est chirurgical. L’approche classique a fait preuve de son efficacité. Les progrès récents des explorations préopératoires et le dosage peropératoire de la PTh ont rendu possible une approche mini-invasive. Des controverses persistent quant à la prise en charge de l’hPTP asymptomatique dont l’indicationthérapeutique doit être bien étudiée.Mots-clés : hyperparathyroïdie primaire, adénome, glande parathyroïde, parathormone, scintigraphie, parathyroïdectomi

Extension of the Hamaneh - Taylor model using the macroscopic polarization for the description of chiral smectic liquid crystals

Chiral smectic liquid crystals exhibit a series of phases, including ferroelectric, antiferroelectric and ferrielectric commensurate structures as well as an incommensurate SmCalpha phase. We carried out an extension of the phenomenological model, recently presented by M. B. Hamaneh and P. L. Taylor, based upon the distorted clock model

L’ectopie des glandes parathyroides dans la chirurgie de l’hyperparathyroidie

Introduction : L’ectopie parathyroïdienne est la cause d’échec la plus fréquente de la chirurgie de l’hyperparathyroïdie, entrainant le plus souvent des reprises chirurgicales. Son diagnostic topographique pré-opératoire reste difficile malgré le progrès dans les différentes explorations radiologiques. Le diagnostic per-opératoire doit être guidé par une stratégie de dissection de référence. Le but de travail est d’étudier la stratégie de recherche des parathyroides lors de leur chirurgie.Matériels et méthodes : Il s’agit d’une étude rétrospective à propos de 137 patients (162 glandes parathyroïdes ectopiques) parmi 572 patients opérés d’une hyperparathyroïdie, colligés sur une période de 11 ans (Janvier 2001-Décembre 2011). Tous les patients ont bénéficié d’une imagerie pré-opératoire et ont été opérés sous anesthésie générale.Résultats : L’âge moyen était de 49 ans (11-71 ans) et le sex-ratio de 1,04. Une hyperparathyroïdie primaire était présente chez 26 patients (18,98%) et une hyperparathyroïdie secondaire à une insuffisance rénale chronique chez 111 patients (81,02%).Une cervicotomie par voie classique avec exploration des 2 loges thyroïdiennes a été réalisée dans 136 cas. Dans les cas où la parathyroïde n’a pas été retrouvée, un geste opératoire a été associé. Ce geste consistait en un curage médiastino-récurrentiel (15 cas), une thymectomie (12 cas) et une lobectomie thyroïdienne (9 cas). Un seul patient a eu une thoracotomie en chirurgie thoracique, sans abord cervical classique. Sur les 162 glandes parathyroïdes ectopiques retenues dans l’étude, 68 étaient des glandes parathyroïdes inférieures. Les localisations de celles-ci étaient par ordre de fréquence le thymus (26 cas), le ligament thyro-thymique (14 cas), le médiastin antéro-supérieur (5 cas) et la gaine carotidienne (3 cas). Vingt glandes parathyroïdes inférieures n’ont pas été retrouvées sur les 68 (29,41%). Le nombre des glandes parathyroïdes supérieures ectopiques était de 94 sur 162. Leurs localisations étaient par ordre de fréquence le pôle supérieur (33 cas), le pédicule supérieur (20 cas), la région rétro-oesophagienne (15 cas), la gaine carotidienne (11 cas), intra-thyroïdienne (5 cas) et le médiastin postéro-supérieur (2 cas). Huit glandes parathyroïdes supérieures n’ont pas été trouvées sur les 94 (8,51%). Au total, sur les 162 glandes parathyroïdes ectopiques, 28 n’ont pas été retrouvées (17,28%).Conclusion : L’imagerie est un moyen incontournable à la recherche d’une glande parathyroïde ectopique. Lorsqu’elle n’est pas retrouvée dans sa localisation habituelle, la stratégie de dissection chirurgicale doit être méthodique.Mots-clés : glande parathyroïde, ectopie, hyperparathyroïdie, imagerie, parathyroïdectomieIntroduction: The ectopic parathyroid is the most common cause of failure of hyperparathyroidism surgery, resulting often in reoperations. Its preoperative topographic diagnosis remains difficult despite advances in various imaging studies. The intraoperative diagnosis should be guided by a reference strategy of dissection.Materials and Methods: This is a retrospective study of 137 patients (162 ectopic parathyroid glands) among 572 patients undergoing hyperparathyroidism surgery, collected over a 11-year period (January 2001-December 2011). All patients underwent preoperative imaging and were operated under general anesthesia.Results: The mean age was 49 years (11-71 years) and the sex-ratio 1.04. Primary hyperparathyroidism was present in 26 patients (18.98%) and hyperparathyroidism secondary to chronic renal failure in 111 patients (81.02%). Cervicotomy through traditional approach with bilateral exploration was performed in 136 cases. In cases where the parathyroid was not found, a surgical procedure was performed. This act consisted in mediastinal-recurrential lymphadenectomy (15 cases), thymectomy (12 cases) and thyroid lobectomy (9 cases). One patient had a thoracotomy in thoracic surgery department without conventional cervical approach. Among the 162 ectopic parathyroid glands included in the study, 68 were inferior parathyroid glands. The locations of these were in order of frequency the thymus (26 cases), the thyro-thymic ligament (14 cases), the antero-superior mediastinum (5 cases) and the carotid sheath (3 cases). Twenty inferior parathyroid glands were not found among the 68 (29,41%). The number of ectopic superior parathyroid glands was 94 of 162. Their locations were in order of frequency the upper pole (33 cases), the superior pedicle (20 cases), the retro-esophageal region (15 cases), the carotid sheath (11 cases), intra-thyroid (5 cases) and the postero-superior mediastinum (2 cases). Eight superior parathyroid glands were not found among the 94 (8.51%). In total, among 162 ectopic parathyroid glands, 28 were not found (17,28%).Conclusion: Imaging is essential to search an ectopic parathyroid gland. When not found in its usual location, the strategy of surgical dissection should be methodical.Keywords: parathyroid gland, ectopia, hyperparathyroidism, imaging, parathyroidectom

Implementation of a multilayer statistical physics model to interpret the adsorption of food dyes on a chitosan film

This paper reports the application of an advanced multilayer model to study the adsorption of food dyes FD&C blue No. 2, acid red 18, FD&C red No. 2, and FD&C yellow 5 from aqueous solutions with a chitosan film. These dyes' adsorption mechanisms were discussed and analyzed at 298–328 K and pH 4–7 via statistical physics calculations. Physicochemical parameters were utilized to explain the dye adsorption at the molecular scale. Modeling results showed dye aggregation phenomena where each functional group of chitosan film adsorbed several dye molecules simultaneously at different tested temperatures. Aqueous solution temperature reduced the dye adsorption capacities, attributed to the exothermic nature of dye removal. The chitosan film was more effective for the adsorption of dye FD&C yellow 5. The estimated adsorption energies for dye-chitosan film and dye-dye interactions confirmed an exothermic physisorption associated with van der Waals forces and hydrogen bonding. This study's results contributed to expanding the knowledge on the adsorption mechanisms of dye molecules using biopolymers like chitosan

Comparative Study of Human and Automated Screening for Antinuclear Antibodies by Immunofluorescence on HEp-2 Cells

Background: Several automated systems had been developed in order to reduce inter-observer variability in indirect immunofluorescence (IIF) interpretation. We aimed to evaluate the performance of a processing system in antinuclear antibodies (ANA) screening on HEp-2 cells. Patients and Methods: This study included 64 ANA-positive sera and 107 ANA-negative sera that underwent IIF on two commercial kits of HEp-2 cells (BioSystems® and Euroimmun®). IIF results were compared with a novel automated interpretation system, the “CyclopusCADImmuno®” (CAD). Results: All ANA-positive sera images were recognized as positive by CAD (sensitivity = 100%), while 17 (15.9%) of the ANA-negative sera images were interpreted as positive (specificity = 84.1%), =0.799 (SD=0.045). Comparison of IIF pattern determination between human and CAD system revealed on HEp-2 (BioSystems®), a complete concordance in 6 (9.37%) sera, a partial concordance (sharing of at least 1 pattern) in 42 (65.6%) cases and in 16 (25%) sera the pattern interpretation was discordant. Similarly, on HEp-2 (Euroimmun®) the concordance in pattern interpretation was total in 5 (7.8%) sera, partial in 39 (60.9%) and absent in 20 (31.25%). For both tested HEp-2 cells kits agreement was enhanced for the most common patterns, homogenous, fine speckled and coarse speckled. While there was an issue in identification of nucleolar, dots and nuclear membranous patterns by CAD. Conclusion: Assessment of ANA by IIF on HEp-2 cells using the automated interpretation system, the “CyclopusCADImmuno®” is a reliable method for positive/negative differentiation. Continuous integration of IIF images would improve the pattern identification by the CAD