On triangularizability of the commutant of a single matrix

AbstractThe main purpose of this paper is to characterize triangularizable matrices A∈Mn(F) whose commutants are triangularizable, where F is an arbitrary field. More precisely, we show that the commutant of a triangularizable matrix A∈Mn(F) is triangularizable if and only if for any eigenvalue λ of A, the corresponding Jordan blocks in the Jordan canonical form of A have distinct sizes

The Effect of Clearance on the Performance of Machine Husking Rubber Rolls for Two

تاثير الخلوص  بين الاسطوانات لنوع الماكنة Yanmar rubber roll- ST  50 على نوعية تقشير الرز ونسبة التكسر لتقييم  صنفين من الرز تارم هاشمي وديلماني والخلوص بين الاسطوانات لمكائن التقشير تحت ثلاث مستويات مختلفة 0.4,0.6 و 0.8 ملم. باستخدام تصميم التجربة CRD  وبثلاث مكررات اظهرت النتائج تفوق صنف الرز تارم هاشمي معنويا على صنف الرز ديلماني في جميع الصفات المدروسة. كانت هناك علاقة ايجابية بين زيادة الخلوص على نسبة الحبة الكاملة والرز الخام وعلاقة سلبية مع زيادة نسبة الحبوب المتشققة والتكسر وكفاءة التقشير .The effect of clearance between cylinders of  machine husking rubber rolls (type Yanmar rubber roll – ST 50) on rice husk quality and breakage percentage was evaluated for two cultivars of rice. Tarm Hashemi (TH) and Daillman (DM) and clearance between cylinders of machine husking rubber at three different levels of 0.4, 0.6 and 0.8mm.The experiment was done in factorial experiment under complete randomized design (CRD) with three replications the results indicate  that the TH cultivar is significantly better than the D M in all studied traits. There was a negative relationship between increased clearance with head rice percentage and brown rice percentage in addition to the positive relationship between the increased percentage of cracked grain ,broken rice percentage and husking efficiency

A finite-difference formulation of elastic rod for the design of actively bent structures

A discrete formulation of elastic rod has been tailored for the particular design task of geometric modelling, form finding and analysis of actively bent structural systems. The rod element is fully described by using vector based quantities, hence making it easy to implement and be suitable for explicit resolution methods such as the Dynamic Relaxation (DR). From this point of view, the model under consideration aims to provide a natural enhancement, of existing DR schemes of elastic rods, primarily formulated for analysis/design of stressed spline structures with isotropic cross-section, whilst, the proposed formulation allows for the general case of initially straight rods with anisotropic cross-section and torsionalstiffness effects, to be taken into consideration. In order to avoid numerical conditioning problems, the method adopts a reduced Degrees of Freedom approach, however, the design limitations usually involved with such an approach, are ‘removed’ by adopting the Bishop theory of framed curves, hence making it possible to reduce to only three (translations) the Degrees of Freedom to be explicitly computed by numerical integration of the corresponding acceleration terms

Form finding and structural analysis of actively bent timber grid shells

Grid shells are efficient structural systems covering large open spaces with relatively small amount of materials. Also, post forming techniques allow realization of geometrically complex (free-form) shapes by means of standard connection systems. However, due to complexity of the analysis–design process, they are rarely utilized in construction design. In this paper, a ‘facilitating’ numerical framework is introduced in which, for a given continuous reference shape, a geometrically similar discrete model is found by implementation of a six degree of freedom formulation of the Dynamic Relaxation method, to handle members bending and torsional stiffness. A grid cutting pattern algorithm is introduced, as well as methods to numerically simulate the double-layer construction technique and a novel (single-node) cylindrical joint model. The methods are extensively tested and validated on a range of structures, from ‘simple’ single-rod cases to more complex, actively bent, grid shell frameworks

The role of ILâ 5 in bleomycinâ induced pulmonary fibrosis

Eosinophils are known to express cytokines capable of promoting fibrosis. Interleukinâ 5 (ILâ 5) is important in regulating eosinophilopoiesis, eosinophil recruitment and activation. Lung ILâ 5 expression is elevated in pulmonary fibrosis, wherein the eosinophil is a primary source of fibrogenic cytokines. To determine the role of ILâ 5 in pulmonary fibrosis, the effects of antiâ ILâ 5 antibody were investigated in a model of bleomycinâ induced pulmonary fibrosis. Fibrosis was induced in mice by endotracheal bleomycin treatment. Animals were also treated with either antiâ ILâ 5 antibody or control IgG. Lungs were then analyzed for fibrosis, eosinophil influx, chemotactic activity, and cytokine expression. The results show that a primary chemotactic activity at the height of eosinophil recruitment is ILâ 5. Furthermore, antiâ ILâ 5 antibody caused significant reduction in lung eosinophilia, cytokine expression, and fibrosis. These findings taken together suggest an important role for ILâ 5 in pulmonary fibrosis via its ability to regulate eosinophilic inflammation, and thus eosinophilâ dependent fibrogenic cytokine production. J. Leukoc. Biol. 64: 657â 666; 1998.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141191/1/jlb0657.pd

Biosorption and recovery of copper and zinc from aqueous solutions by nonliving biomass of marine brown algae of Sargassum sp.

In this study, the biosorption properties of a pre-treated nonliving biomass of marine brown algae of Sargassum species in the removal of Cu 2+ and Zn2+ ions were investigated. Kinetics, equilibrium isotherms, recovery of metals and regeneration of the Sargassum biomass were carried out under different laboratory conditions using batch reactor. Biosorption of Cu2+ and Zn2+ was rapidly occurred onto Sargassum biomass and most of the sorbed metal was bound in less than 60 min. The removal performance for Zn2+ by the biomass was found more than Cu2+, with maximum uptake values of 1.914 and 1.314 mg g-1 dry weight biomass for Zn2+ and Cu2+, respectively. Optimum biosorption pH value of Cu2+ and Zn2+ was determined as 5 at lab temperature. At the optimal condition, metal ion uptake increased with initial Cu2+ and Zn2+ concentration upto 200 and 500 mg L-1, respectively. The Cu2+ and Zn 2+ uptake by Sargassum biomass was best described by pseudo-second order rate equation. The results showed that the Freundlich isotherm model was suitable for describing the passive biosorption of Cu2+ and Zn 2+ by the dead biomass of Sargassum. Removal of the biosorbed Cu 2+ and Zn2+ from Sargassum biomass was successfully achieved by eluting with 0.1 M HNO3 for 15 min and a high degree of metal recovery was observed. For optimum operation in the subsequent metal uptake cycle, regeneration of the Sargassum biomass was efficiently performed by 0.1 M CaCl2 for 15 min. In repeated use of biomass experiment, the Cu2+ and Zn2+ uptake capacity of Sargassum biomass was approximately retained and no significant biomass change took place after three biosorption-desorption cycles. © 2006 Asian Network for Scientific Information

L’esthesioneuroblastome olfactif : a propos de 7

Introduction : L’esthésioneuroblastome est une tumeur maligne rare développée aux dépens du neuro-épithélium olfactif. C’est l’une des plus rares tumeurs des fosses nasales. L’objectif de ce travail est d’étudier à travers une revue de la littérature, les caractéristiques histocliniques, les modalités thérapeutiques et les facteurs pronostiques de cette tumeur.Matériel et méthodes : Etude rétrospective à propos de sept cas d’esthésioneuroblastome olfactif traités dans le service d’ORL et de CCF de l’hôpital Farhat Hached de Sousse sur une période de 26 ans.Résultats : L’âge moyen de nos patients était de 36 ans avec une prédominance féminine. La symptomatologie clinique était dominée par l’obstruction nasale et l’épistaxis. Cinq patients étaient classés stade B de Kadish, et 2 stade C. Six patients ont eu un traitement chirurgical dont cinq ont eu une radiothérapie post opératoire. Une patiente avait une importante extension locorégionale et était au dessus de tout traitement à visée curative. Trois malades sont en rémission complète avec un recul moyen de 6 ans. Trois malades ont présenté une récidive tumorale.Conclusion : L’esthésioneuroblastome olfactif est une tumeur naso-sinusienne maligne rare, caractérisée par son polymorphisme clinique et son agressivité locale. Malgré la chirurgie et la radiothérapie, le pronostic reste réservé à long terme.Mots clés : Esthésioneuroblastome olfactif - Imagerie- Immunohistochimie- Chirurgie -RadiothérapieIntroduction: Introduction: Esthesioneuroblastoma is a rare malignant tumor, which develops from olfactory neuroepithelium and is one of the rarest tumors of the nasal cavity. The aim of this study is to specify through a review of the literature, histoclinic characteristics, therapeutic terms and prognostic factors of this tumor.Material and methods: a retrospective study concerning seven cases of olfactory neuroblastoma treated in the department of otolaryngology- Head and Neck surgery at Farhat Hached Hospital Sousse over a period of 26 years.Results: The mean age of our patients was 36 years. A female predominance was noted. Clinical symptomatology was dominated by nasal obstruction and epistaxis. Five patients were classified as Kadish B and 2 patients as Kadish C. Six patients underwent surgicaltreatment, five of them had postoperative radiotherapy. One patient was above all therapeutic resources. 3 patients are in complete remission with a mean follow-up of 6 years. Recurrence was observed for the remaining patients.Conclusion: olfactory esthesioneuroblastoma is a rare sinonasal malignant tumor, characterised by clinical polymorphism and local agressivity. In spite of the surgery and the radiotherapy, the forecast remains reserved in the long term.Key words: Olfactory neuroblastoma – Imagery – Immunohistochemestry – Surgery - Radiotherap

Biosorption and recovery of copper and zinc from aqueous solutions by nonliving biomass of marine brown algae of Sargassum sp.

In this study, the biosorption properties of a pre-treated nonliving biomass of marine brown algae of Sargassum species in the removal of Cu 2+ and Zn2+ ions were investigated. Kinetics, equilibrium isotherms, recovery of metals and regeneration of the Sargassum biomass were carried out under different laboratory conditions using batch reactor. Biosorption of Cu2+ and Zn2+ was rapidly occurred onto Sargassum biomass and most of the sorbed metal was bound in less than 60 min. The removal performance for Zn2+ by the biomass was found more than Cu2+, with maximum uptake values of 1.914 and 1.314 mg g-1 dry weight biomass for Zn2+ and Cu2+, respectively. Optimum biosorption pH value of Cu2+ and Zn2+ was determined as 5 at lab temperature. At the optimal condition, metal ion uptake increased with initial Cu2+ and Zn2+ concentration upto 200 and 500 mg L-1, respectively. The Cu2+ and Zn 2+ uptake by Sargassum biomass was best described by pseudo-second order rate equation. The results showed that the Freundlich isotherm model was suitable for describing the passive biosorption of Cu2+ and Zn 2+ by the dead biomass of Sargassum. Removal of the biosorbed Cu 2+ and Zn2+ from Sargassum biomass was successfully achieved by eluting with 0.1 M HNO3 for 15 min and a high degree of metal recovery was observed. For optimum operation in the subsequent metal uptake cycle, regeneration of the Sargassum biomass was efficiently performed by 0.1 M CaCl2 for 15 min. In repeated use of biomass experiment, the Cu2+ and Zn2+ uptake capacity of Sargassum biomass was approximately retained and no significant biomass change took place after three biosorption-desorption cycles. © 2006 Asian Network for Scientific Information

Les lymphomes de l’anneau de Waldeyer traitement et pronostic

Les lymphomes non Hodgkiniens (LNH) qui prennent naissance au niveau de l’anneau de Waldeyer constituent une entité bien particulière tant sur le plan clinique, thérapeutique que pronostique. Les auteurs rapportent une étude rétrospective de 44 observations de LNH de l’anneau de Waldeyer colligées entre 1995 et 2002. Une chimiothérapie exclusive aété indiquée chez 80,6% des malades et une association chimio-radiothérapie a été réalisée chez 19,4%. Le taux de survie globale était de 42% à 5 ans. Dans notre étude quatre facteurs de mauvais pronostic ont été individualisés : un âge ≥ à 40 ans, les stades d’Ann Arbor II, III et IV, un taux de LDH ≥ 1,5 fois la normale et la survenue de rechute.Mots-clés : Lymphome, anneau de Waldeyer, chimiothérapie, radiothérapie, pronosti

Optimal Decision Making Framework of an Electric Vehicle Aggregator in Future and Pool markets

Electric vehicle (EV) aggregator, as an agent between the electricity market and EV owners, participates in the future and pool market to supply EVs’ requirement. Because of the uncertain nature of pool prices and EVs’ behaviour, this paper proposed a two-stage scenario-based model to obtain optimal decision making of an EV aggregator. To deal with mentioned uncertainties, the aggregator’s risk aversion is applied using conditional value at risk (CVaR) method in the proposed model. The proposed two-stage risk-constrained decision-making problem is applied to maximize EV aggregator’s expected profit in an uncertain environment. The aggregator can participate in the future and pool market to buy the required energy of EVs and offer optimal charge/discharge prices to the EV owners. In this model, in order to assess the effects of EVs owners’ reaction to the aggregator’s offered prices on the purchases from electricity markets, a sensitivity analysis over risk factor is performed. The numerical results demonstrate that with the application of the proposed model, the aggregator can supply EVs with lower purchases from markets