bluuebunny/crossref_metadata_2025 huggingface dataset:
Le climat méditerranéen en France et en U.R.S.S
Authors: Douguedroit Annick , Zimina R.P.
Published: June 2011

Mediterranean climate in France and in U.S.S.R. In U.S.S.R., the Mediterranean climate is limited to a coastal strip, along the Black Sea (the Southern coast of the Crimea and the area of Novorossiisk) and the Caspian Sea (Southern Daghestan and Azerbaïdjan). Its best criterion is the existence of summer lowest rainfall, with a number of dry months defined by the Gaussen index P/2T , which allows us to separate the Mediterranean climate from the continental climate with summer heaviest rainfall and from the more humide Colchidian climate. Precipitations fall down during the heart of the cold season along the coast of the Black Sea, and mainly in autumn in the area of the Caspian Sea. But the main difference between the Mediterranean climates of France and U.S.S.R. is thermal. Winters are much colder in the Eastern area, even in Southern Azerbaïdjan around 40° latitude. Frost lasts , in Yalta, three mounths on average and the snowcover remains during two months on January and February. The continental, even arctic, cold winter spells slide down to the Caspian Sea around 40° latitude very easiley ; the Black Sea coast in shelter of the Taurus and the Western Caucasus mountains has less cold temperatures as the same latitude.
Le peuplement dans le Caucase Oriental, formes traditionnelles et actuelles. Comparaison avec les Alpes françaises
Authors: Lappo M. , Djaochvili M.
Published: June 2011

La population et le peuplement dans le Caucase oriental et dans les Alpes du Sud sont ici mis en parallèle, dans leurs contextes respectifs économique, politique et social. Sur bien des points, des rapprochements sont possibles entre les deux massifs montagneux secs. Il y a, ainsi, en commun, la grande ancienneté d'un peuplement à fondement agro-pastoral s'appuyant en particulier sur une transhumance ovine multiséculaire. Mais si Aouls et villages perchés ont vu, dans les deux espaces, leurs populations migrer vers les piémonts de façon massive, c'est dans des conditions ethniques et politico-économiques très différentes.

Les uns (Alpes du Sud) verront leurs migrants trouver du travail dans un bas-pays provençal urbain partageant avec les montagnes une histoire commune ; les autres (Caucase oriental) devront s'adapter à un monde économique, politique et linguistique nouveau. Les uns verront aussi leur population rurale décliner profondément et une réelle urbanisation interne aux massifs se développer parallèlement, tandis que les autres, par un dynamisme démographique ininterrompu jusqu'à nos jours, maintiendront une population importante, dans les moyennes et basses altitudes au moins, sans qu'un véritable réseau urbain se développe dans la montagne caucasienne, toujours économiquement très subordonnée au piémont. Ce relatif surpeuplement caucasien s'explique en partie par l'intérêt d'une économie auxiliaire domestique (lopins et bétail individuels) tout à fait abandonnée dans les Alpes du Sud, au contraire assiégées par l'économie de loisirs urbaine, libérale, peu peuplante et source de déstructurations diverses.
Les grandes zones de tourisme culturel : définition et problèmes de saturation
Authors: Mirloup Joel
Published: June 2011

The concept of «zone», about cultural tourism, is the result of two sorts of approachs. The first si rather the product of a global, subjective and «general public» perception. The second is a matter for the geographical analysis : the «cultural tourism» is first generated by internal movements.

In these areas, strongly polarized or not, semetimes with a complicated structure, specialized or polyvalent, the monuments are unequally satured. The spreading or the tourist frequenting in the space - i.e. the amplification of the «zone» character — seems the best solution, rather than stagger the frequenting in the time.
Âge, évolution, durée des grands littoraux touristiques
Authors: Coulet Louise
Published: June 2011

L'attention portée à l'âge des littoraux touristiques en méditerranée septentrionale principalement permet de dégager des phases de genèse et de croissance, de crise et de mutation et de constater la durée de certains littoraux. Ce fonctionnement dans le temps de ces espaces particuliers est basé sur les relations mouvantes qui unissent flux de clientèles extérieures et la région d'accueil.

La région touristique en tentant de répondre le mieux possible aux sollicitations extérieures organise son espace d'une manière de plus en plus complexe et multiplie les qualités qui la rendent attractive.
A comparative study of the Au-catalyzed cyclization of hydroxy-substituted allylic alcohols and ethers
Authors: Biannic Berenger , Ghebreghiorgis Thomas , Aponick Aaron
Published: June 2011

The Au(I)-catalyzed cyclization of hydroxyallylic ethers to form tetrahydropyrans is reported. Employing (acetonitrile)[(o-biphenyl)di-tert-butylphosphine]gold(I) hexafluoroantimonate, the cyclization reactions were complete within minutes to hours, depending on the substrate. The reaction progress was monitored by GC, and comparisons between substrates demonstrate that reactions of allylic alcohols are faster than the corresponding ethers. Additionally, it is reported that Reaxa QuadraPureTM MPA is an efficient scavenging reagent that halts the reaction progress.
Partial Virological Response to Entecavir in Treatment-Naive Patients with Chronic Hepatitis B
Authors: Chon Young Eun , Kim Seung Up , Lee Chun Kyon , Heo Jeong , Kim Ja Kyung , Yoon Ki Tae , Cho Mong , Lee Kwan Sik , Kim Dong Hwan , Choi Eun Hee , Park Jun Yong , Kim Do Young , Chon Chae Yoon , Han Kwang-Hyub , Ahn Sang Hoon
Published: June 2011

Background

The proposed definition of a partial virological response (PVR) to nucleos(t)ide analogue therapy in the 2009 European Association for the Study of the Liver (EASL) guidelines is based on limited evidence, especially in terms of the cutoff HBV DNA level and the time point at which to judge it. This study assessed optimal PVR criteria for predicting virological response (VR) at week 96 in treatment-naive patients with chronic hepatitis B (CHB) receiving entecavir (ETV).

Methods

A total of 175 patients (126 men, 49 women) who completed 96 weeks of first-line ETV therapy were prospectively recruited. For predicting VR at week 96, the area under the receiver operating characteristic curve (AUC) was used to find the optimal time point and the Youden index was used to calculate the optimal cutoff HBV DNA level.

Results

After 96 weeks of ETV therapy, 139 (79.4%) patients achieved VR. The AUC at week 48 was significantly better than that at week 24 for predicting VR at week 96 ( P=0.023). The optimal cutoff HBV DNA level at week 48 was 35 IU/ml. Forty-one (23.4%) patients met this PVR criteria of ETV (HBV DNA level >35 IU/ml at week 48).

Conclusions

An HBV DNA level >35 IU/ml at week 48 is the optimal PVR criteria for predicting non-VR at week 96 in treatment-naive patients with CHB who are receiving ETV. This study supports the proposed EASL PVR for ETV based on scientific evidence.
Pleconaril-Resistant Chronic Parechovirus-Associated Enteropathy in Agammaglobulinaemia
Authors: van de Ven Annick AJM , Douma Jan Willem , Rademaker Carin , van Loon Anton M , Wensing Annemarie MJ , Boelens Jaap-Jan , Sanders Elisabeth AM , van Montfrans Joris M
Published: June 2011

A 14 year old common variable immunodeficiency patient developed severe protein-losing enteropathy. A chronic enteral infection with human parechovirus type 1 and norovirus was diagnosed. Treatment strategies aimed at virus eradication and providing supportive care were ineffective. The antipicornavirus agent pleconaril did not have any effect on viral replication. Symptoms improved on immunosuppressive therapy, suggesting infection- related immune dysregulation in an immuno-compromised host.
Interpretation of Genotypic HIV-1 Resistance to Darunavir and Virological Response: Validation of Available Systems and of a New Score
Authors:   TMC114-C226 study group,   ARCA study group, De Luca Andrea , Giambenedetto Simona Di , Maserati Renato , Gianotti Nicola , Narciso Pasquale , Antinori Andrea , Perri Giovanni Di , Prosperi Mattia CF , Baldanti Fausto , Micheli Valeria , Zazzi Maurizio , Perno Carlo F , Santoro Maria M
Published: June 2011

Background

There is not yet consensus on interpretation of genotypic HIV-1 resistance to darunavir (DRV). We validated existing rules and a newly derived score.

Methods

Protease inhibitor (PI)-failing patients starting a DRV/ritonavir-based regimen, with available baseline resistance genotypes, were extracted from three Italian databases. Virological response (VR) was analysed between 4 and 32 follow-up weeks, defined as a drop from baseline HIV RNA of ≥2 log10 or a value <50 copies/ml if the last measurement had been obtained at ≤12 weeks and as HIV RNA<50 copies/ml if it had been obtained at >12 weeks of follow-up. DRV/ritonavir resistance was interpreted by seven algorithms. A new weighted score (DRV-2009) was derived and validated, analysing associations of protease mutations with VR.

Results

A total of 217 patients were analysed, with a mean (±sd) follow-up time of 17 (±9) weeks. At baseline, median HIV RNA was 4.26 log10 copies/ml (IQR 3.11-5.03); VR was achieved in 135/217 (62%) patients. Adjusting for use of a new drug class, number of previous PIs experienced, CD4+ T-cell count and HIV RNA, only the Rega DRV/ritonavir interpretation was significantly associated with VR (per increase in susceptibility category, OR 1.94, 95% CI 1.32–2.86; P<0.001). The DRV-2009 score V11I+L33F+R41K+I47V+2*I-50V+2*I54M+K55R+D60E+L74P+L76V+N88D+2*L89V– L10I/V–I13V–G16E–G48V–F53I/L–I62V–I66F–V77I (<0 indicating susceptibility, 0–1 intermediate resistance and ≥2 resistance) correlated with VR in the derivation set ( n=132, R=0.395; P<0.001). In the validation set ( n=85), after adjusting for mutual interpretation and new use of enfuvirtide, DRV-2009 ( P=0.017) and Rega ( P=0.013) were both independently associated with VR.

Conclusions

In contrast to the other algorithms, both the DRV-2009 score and Rega interpretation showed a robust predictive capacity of VR to DRV/ritonavir-con-taining regimens.
Rheology and zeta potential of cement pastes containing calcined silt and ground granulated blast-furnace slag
Authors: Safi B. , Benmounah A. , Saidi M.
Published: June 2011

This study aimed to analyse the re-use of dam silt as a supplementary binder for self-compacting concrete (SCC). When burnt, silt becomes more reactive because the kaolin it contains is converted into metakaolin. Portland cement, calcined or burnt silt and ground granulated blast furnace slag were used in this research. Cement pastes were prepared with blends containing two or three of these materials. The replacement ratio for burnt silt in both cases was 10 % and 20 % by cement weight and the ratio for the slag was a constant 30 % by weight of the blend. Rheological and zeta potential tests were conducted to evaluate paste electrokinetics and rheological behaviour. The findings showed that burnt silt is apt for use as an addition to cement for SCC manufacture.
Little Brown Myotis Persist Despite Exposure to White-Nose Syndrome
Authors: Dobony Christopher A. , Hicks Alan C. , Langwig Kate E. , von Linden Ryan I. , Okoniewski Joseph C. , Rainbolt Raymond E.
Published: June 2011

We monitored a maternity colony of little brown myotis Myotis lucifugus on Fort Drum Military Installation in northern New York in 2009 and 2010 for impacts associated with white-nose syndrome. Declines in colony numbers presumed to be caused by white-nose syndrome were initially discovered in the spring 2009. Although colony numbers have continued to decline, we determined that a minimum of 12 individual banded female little brown myotis survived over multiple years despite exposure to white-nose syndrome. Our results also provide evidence that 14 of 20 recaptured female little brown myotis were able to heal from wing damage and infection associated with white-nose syndrome within a given year, and seven of eight recaptures from within both 2009 and 2010 showed evidence of reproduction.
Thermal Buckling of Simply Supported FGM Square Plates
Authors: Bouazza M. , Tounsi A. , Adda-Bedia E.A. , Megueni A.
Published: June 2011

Thermal buckling behaviour of FGM square plates with simply supported edges has been studied in this note using the classic plate theory (CPT). It is assumed that the nonhomogeneous mechanical properties of the plate, graded through thickness, are described by a power-law FGM (simply called P-FGM) and sigmoid FGM (S-FGM). The plate is assumed to uniform temperature rise. Resulting equations are employed to obtain the closed-form solutions for the critical buckling temperature change of FGM. The results are compared with the results of the first order shear deformation theory.
Analytical and Finite Element Analysis for Short Term O-Ring Relaxation
Authors: Diany Mohammed , Aissaoui Hicham
Published: June 2011

The like-rubber O-ring gaskets are widely used in hydraulic and pneumatic equipments to ensure the sealing of the shaft, the pistons and the lids. The correct operation is due to the good tightening of the joint that generate a sufficient contact pressure able to confine the fluids inside rooms or to prevent their passage from one compartment to another. Several studies are carried out to model the O-ring behavior but without taking in account the effect of the relaxation and creep phenomena. In this article, an axisymmetric finite element model is proposed to study the O-ring relaxation during the first hours of its installation in the unrestrained axial loading case. The results of the numerical model are compared with an analytical approach results based on the classical Hertzian theory of the contact. The effects of the o-ring mechanical and geometrical characteristics are examined. The contact stress profiles and the peak contact stresses are determined versus the time relaxation in order to specify the working conditions thresholds.
A New Methodology for an Optimal Shape Design
Authors: El Alem W. , El Hami A. , Ellaia Rachid
Published: June 2011

The aim of this paper is to study the implementation of an efficient and reliable methodology for shape optimization problems where the objective function and constraints are not known explicitly and are dependent on the Finite Element Analysis (FEA). It is based on the Simultaneous Perturbation Stochastic Approximation (SPSA) method for solving unconstrained continuous optimization problems. We also propose Penalty SPSA (PSPSA) for solving constrained optimization problems, the constraints are handled using exterior point penalty functions within an algorithm that combines SPSA and exact penalty transformations. This paper presents a new structural optimization methodology that combines shape optimization, geometric modeling, FEA and PSPSA method to successfully optimize structural optimization problems. Several tests have been performed on some well known benchmark functions to demonstrate the robustness and high performance of the suggested methodology. In addition, an illustrative two-dimensional structural problem has been solved in a very efficient way. The numerical results demonstrate the robustness and high performance of the suggested methodology for structural optimization problems.
A Multi-Scale Analysis of Materials Reinforced by Inclusions Randomly Oriented in the Ply Plane
Authors: Lacoste Emmanuel , Fréour Sylvain , Jacquemin Frédéric
Published: June 2011

The present work aims to investigate the validity of Eshelby-Kröner self-consistent model [1] for thermoelastic behaviour, in the case of a material reinforced by inclusions randomly oriented in the ply plane. The model provides predictive information on the properties and multi-scale mechanical states experienced by the material, accounting for its constituents properties, but also their morphology. However, it cannot reliably account for multiple inclusion morphologies (shape and orientation) in the material [2, 3, 4]. A study of the two applicable formulations and their limits leads to suggest a mixed formulation as an acceptable compromise between those alternatives. The results of this original approach are also described in the case of a thermo-mechanical load.
The Non Destructive Testing Methods Applied to Detect Cracks in the Hot Section of a Turbojet
Authors: Bennoud Salim , Mourad Zergoug
Published: June 2011

All aircraft whatever they are; are regularly audited. These controls are mainly visual and external; other controls such as "major inspection" or "general revisions” are more extensive and require the dismantling of certain parts of the aircraft. Some parts of the aircraft remain inaccessible and are therefore more difficult to inspect (compressor, combustion chamber, and turbine). The means of detection must ensure controls either during initial construction, or at the time of exploitation of all the parts. The Non destructive testing (NDT) gathers the most widespread methods for detecting defects of a part or review the integrity of a structure. The aim of this work is to present the different (NDT) techniques and to explore their limits, taking into account the difficulties presented at the level of the hot part of a turbojet, in order to propose one or more effective means, non subjective and less expensive for the detection and the control of cracks in the hot section of a turbojet. To achieve our goal, we followed the following steps: - Acquire technical, scientific and practical basis of magnetic fields, electrical and electromagnetic, related to industrial applications primarily to electromagnetic NDT techniques. - Apply a scientific approach integrating fundamental knowledge of synthetic and pragmatic manner so as to control the implementation of NDT techniques to establish a synthesis in order to comparing between the use of different methods. - To review recent developments concerning the standard techniques and their foreseeable development: eddy current, ultrasonic guided waves ..., and the possibility of the implication of new techniques.
Simulation of Thermo Mechanical Behavior of Structures by the Numerical Resolution of Direct Problem
Authors: Aouragh B. , Chaoufi J. , Fatmaoui H. , Dupré Jean Christophe , Vallée Claude , Atchonouglo Kossi
Published: June 2011

The aim of our study is to develop an approach to both experimental and numerical modeling to the thermal behavior of a material by identifying these thermal parameters. The theoretical part is based on the finite element method which is a starting point to solve a two-dimensional inverse heat. The experimental measurements are performed by infrared thermography. All these experimental and numerical techniques give this method properties valued in the industrial world as the non-intrusive measurements and real-time calculations. For this, we have supported a system of equations and the temperature field, so before starting the inverse problem, we addressed the direct problem by finite element method that has been compared to measures experimental infrared thermography well to check the validity of equations, so it’s the purpose of this work.
Coupling of Adapting Remeshing and Projection Techniques for Numerical Simulations of Forming Processes
Authors: Giraud-Moreau Laurence , Cherouat Abel , Borouchaki Houman
Published: June 2011

As soon as it is question of modelling the follow-up of a geometry during an operation of forming process, the difficulties of meshing and remeshing are often emphases. If the part is situated between rigid tools (case of the deep drawing), in the problems of remeshing are also added difficulties on the management of the contact between the parts. In this case, the deformations are caused by the contact with the tools whose geometry are fixed. The piece must take the shape of the tool geometries during the deformation. In this paper, we present a method coupling an adaptive remeshing strategy and a technique of projection on the tool. The remeshing is based on refinement and coarsening procedures. The projection of the new nodes on the tool allows keeping the contact between the part and the tools. Numerical examples show the efficiency of the method.
Optimization and Identification of the Characteristics of an Hydroformed Structures
Authors: Ayadi A. , Radi Bouchaib , Cherouat Abel , El Hami A.
Published: June 2011

In this study, we present an experimental/numerical methodology which aims to improve 3D thin sheet hydroforming. The experimental study is dedicated to the identification of stress-strain flow by using the Nelder-Mead simplex algorithm optimization from the global measure of displacement and force. Applications are made to the simulation of thin sheet hydroforming using different die geometry to show the efficiency of the proposed methodology to localize plastic instability, thinning of the blanks and damage initiation under different forming condition.
Mechanical Resistance Improvement of Oxidized Metallic Hollow Spheres Stacking
Authors: Davoine Cecile , Mercier Sebastien , Popoff F. , Götzfried A.
Published: June 2011

The oxidation of stainless steel hollow spheres stacking has been studied at 800, 900 and 1,000°C in laboratory air in the range of 200h. The experimental results based on the relative weight gain of oxidized samples revealed an effect of the sphere’s size over the kinetic of oxidation: the quicker oxidation of the material constitued by smallest spheres suggests that the ratio of exposed surface is preponderant in the oxidation mechanisms. A quasi total transformation of the metal into oxides has been observed after 100h at 1000°C. Some simple quasi-static compression tests highlighted a significant deterioration in mechanical resistance for samples oxidized for 100h at 900 and 1,000°C. The global collapse of the oxidized samples could be imputed to the presence of oxides into the shells porosities by implying a decrease of their ductility. In order to improve the mechanical resistance of oxidized hollow spheres stacking, the adding of a dense metallic undercoat is proposed. The concept is tested by producing small samples of nickel-based hollow spheres stacking. The observation of oxidized samples shows that the shell of hollow spheres are not totally oxidized, providing a continuous metallic squeletton beneficial for mechanical stiffness at high temperatures.
Prediction of the Strength of the Adhesively Bonded Joints by the Finite Elements Method
Authors: Tarfaoui Mostapha
Published: June 2011

Using the Abaqus software, the goal of this work is the numerical study of the effects of the static loads on the mechanical behavior, the damage and the strength of the aluminum/aluminum and composite/composite assemblies, very much used in the naval field. For an elastic behavior of the adhesive, it is also a question of modeling the damage of the substrates in composite. This paper presents a numerical investigation on the behavior of structural adhesive bounding under quasi-static loading. It is shown the effects of the adhesive thickness, superposition length and staking lay up on the strength of the adhesively bonded joints under static tensile. A comparison between the use of aluminum and composite laminate substrates is presented and an attempt was made to find out the damage kinetic.
Experimental Study of Dynamic Behaviour of Aluminum/Aluminum and Composite/Composite Double Lap Joints
Authors: Essersi O. , Tarfaoui Mostapha , Boyd S. , Shenoi R.A. , Meraghni F.
Published: June 2011

This paper presents an experimental investigation on the behaviour of structural adhesive bonding under quasi-static and moderately high loading rates. It addresses the effects of the loading rate on the strength of the adhesively bonded joints under dynamic tensile. A comparison has been achieved between the strength and the damage of specimens’ made of aluminium and lamina substrates. High rate tests showed ringing in the force/displacement curves.
Optimization of Tube Hydroforming Process Using Probabilistic Constraints on Failure Modes
Authors: Ben Abdessalem Anis , El Hami A.
Published: June 2011

In metal forming processes, different parameters (Material constants, geometric dimensions, loads …) exhibits unavoidable scatter that lead the process unreliable and unstable. In this paper, we interest particularly in tube hydroforming process (THP). This process consists to apply an inner pressure combined to an axial displacement to manufacture the part. During the manufacturing phase, inappropriate choice of the loading paths can lead to failure. Deterministic approaches are unable to optimize the process with taking into account to the uncertainty. In this work, we introduce the Reliability-Based Design Optimization (RBDO) to optimize the process under probabilistic considerations to ensure a high reliability level and stability during the manufacturing phase and avoid the occurrence of such plastic instability. Taking account of the uncertainty offer to the process a high stability associated with a low probability of failure. The definition of the objective function and the probabilistic constraints takes advantages from the Forming Limit Diagram (FLD) and the Forming Limit Stress Diagram (FLSD) used as a failure criterion to detect the occurrence of wrinkling, severe thinning, and necking. A THP is then introduced as an example to illustrate the proposed approach. The results show the robustness and efficiency of RBDO to improve thickness distribution and minimize the risk of potential failure modes.
Numerical Modelling of a Composite Fuselage Manufactured by Liquid Resin Infusion
Authors: Perret Adrien , Mistou Sébastien , Denaud Louis Etienne , Mollé Thierry , Veyrac Claudia , Karama Moussa
Published: June 2011

FUSCOMP (FUSelage COMPosite) is a Research & Development program which has received the label from the Aerospace Valley competitiveness cluster. It will lead to a test of a composite fuselage demonstrator manufactured by the Liquid Resin Infusion (LRI) process. LRI is based on the moulding of high performance composite parts by infusing liquid resin on dry fibers instead of prepreg fabrics. The study of this proof of concept is based on the TBM 850 airframe, a pressurized business turboprop aircraft currently produced by DAHER-SOCATA. Technical achievements will concern numerical methods and finite elements analysis to be used for the modelling of this aircraft composite fuselage structure. Actual industrial projects face composite integrated structure issues as a number of structures (stiffeners,...) are more and more integrated onto the skins of aircraft fuselage. Indeed the main benefit of LRI is to reduce assembly steps which lead to cycle time gain and thus cost reduction. In particular, infusing components and sub-components at the same time avoids riveting parts altogether. However it is necessary to validate the dimensioning of the studied composite structure.
TNF Mediates the Sustained Activation of Nrf2 in Human Monocytes
Authors: Rushworth Stuart A. , Shah Suharsh , MacEwan David J.
Published: June 2011

Modulation of monocyte function is a critical factor in the resolution of inflammatory responses. This role is mediated mainly by the production of TNF-α. Investigations of the actions of TNF have mostly focused on acute activation of other cell types such as fibroblasts and endothelial cells. Less is known about the effects of TNF on monocytes themselves, and little is known about the regulation of cell responses to TNF beyond the activation of NF-κB. In this study, we investigated the regulation of NF-E2–related factor 2 (Nrf2) cyctoprotective responses to TNF in human monocytes. We found that in monocytes TNF induces sustained Nrf2 activation and Nrf2 cytoprotective gene induction in a TNFR1-dependent manner. Under TNF activation, monocytes increased their expression of Nrf2-dependent genes, including NAD(P)H:quinone oxidoreductase 1 and glutamyl cysteine ligase modulatory, but not heme oxygenase-1. We also showed that autocrine TNF secretion was responsible for this sustained Nrf2 response and that Nrf2 activation by TNF was mediated by the generation of reactive oxygen species. Moreover, we showed that Nrf2-mediated gene induction can modulate TNF-induced NF-κB activation. These results show for the first time, to our knowledge, that TNF modulates prolonged Nrf2-induced gene expression, which in turn regulates TNF-induced inflammatory responses.
Loss of T Cell CD98 H Chain Specifically Ablates T Cell Clonal Expansion and Protects from Autoimmunity
Authors: Cantor Joseph , Slepak Marina , Ege Nil , Chang John T. , Ginsberg Mark H.
Published: June 2011

CD98 H chain (4F2 Ag, Slc3a2) was discovered as a lymphocyte-activation Ag. Deletion of CD98 H chain in B cells leads to complete failure of B cell proliferation, plasma cell formation, and Ab secretion. In this study, we examined the role of T cell CD98 in cell-mediated immunity and autoimmune disease pathogenesis by specifically deleting it in murine T cells. Deletion of T cell CD98 prevented experimental autoimmune diabetes associated with dramatically reduced T cell clonal expansion. Nevertheless, initial T cell homing to pancreatic islets was unimpaired. In sharp contrast to B cells, CD98-null T cells showed only modestly impaired Ag-driven proliferation and nearly normal homeostatic proliferation. Furthermore, these cells were activated by Ag, leading to cytokine production (CD4) and efficient cytolytic killing of targets (CD8). The integrin-binding domain of CD98 was necessary and sufficient for full clonal expansion, pointing to a role for adhesive signaling in T cell proliferation and autoimmune disease. When we expanded CD98-null T cells in vitro, they adoptively transferred diabetes, establishing that impaired clonal expansion was responsible for protection from disease. Thus, the integrin-binding domain of CD98 is required for Ag-driven T cell clonal expansion in the pathogenesis of an autoimmune disease and may represent a useful therapeutic target.
Endoplasmic Reticulum Calcium Depletion Impacts Chaperone Secretion, Innate Immunity, and Phagocytic Uptake of Cells
Authors: Peters Larry Robert , Raghavan Malini
Published: June 2011

A number of immunological functions are ascribed to cell surface-expressed forms of the endoplasmic reticulum (ER) chaperone calreticulin (CRT). In this study, we examined the impact of ER stress-inducing drugs upon cell surface CRT induction and the resulting immunological consequences. We showed that cell surface expression of CRT and secretion of CRT, BiP, gp96, and PDI were induced by thapsigargin (THP) treatment, which depletes ER calcium, but not by tunicamycin treatment, which inhibits protein glycosylation. Surface expression of CRT in viable, THP-treated fibroblasts correlated with their enhanced phagocytic uptake by bone marrow-derived dendritic cells. Incubation of bone marrow-derived dendritic cells with THP-treated fibroblasts enhanced sterile IL-6 production and LPS-induced generation of IL-1β, IL-12, IL-23, and TNF-α. However, extracellular CRT is not required for enhanced proinflammatory responses. Furthermore, the pattern of proinflammatory cytokine induction by THP-treated cells and cell supernatants resembled that induced by THP itself and indicated that other ER chaperones present in supernatants of THP-treated cells also do not contribute to induction of the innate immune response. Thus, secretion of various ER chaperones, including CRT, is induced by ER calcium depletion. CRT, previously suggested as an eat-me signal in dead and dying cellular contexts, can also promote phagocytic uptake of cells subject to ER calcium depletion. Finally, there is a strong synergy between calcium depletion in the ER and sterile IL-6, as well as LPS-dependent IL-1β, IL-12, IL-23, and TNF-α innate responses, findings that have implications for understanding inflammatory diseases that originate in the ER.
Volumetric Differences in Mapped Hippocampal Regions Correlate with Increase of High Alpha Rhythm in Alzheimer′s Disease
Authors: Moretti D. V. , Prestia A. , Fracassi C. , Geroldi C. , Binetti G. , Rossini P. M. , Zanetti O. , Frisoni G. B.
Published: June 2011

Objective. The increase of high alpha relative to low alpha power has been recently demonstrated as a reliable EEG marker of hippocampal atrophy conversion of patients with mild cognitive impairment (MCI) in Alzheimer′s disease (AD). In the present study we test the reliability of this EEG index in subjects with AD. Methods. Correlation between EEG markers and volumetric differences in mapped hippocampal regions was estimated in AD patients. Results. Results show that the increase of alpha3/alpha2 power ratio is correlated with atrophy of mapped hippocampal regions in Alzheimer′s disease. Conclusions. The findings confirm the possible diagnostic role of EEG markers.
Demographic Profile of Older Adults Using Wheeled Mobility Devices
Authors: Karmarkar Amol M. , Dicianno Brad E. , Cooper Rosemarie , Collins Diane M. , Matthews Judith T. , Koontz Alicia , Teodorski Emily E. , Cooper Rory A.
Published: June 2011

The purpose of this study was to determine whether the use of wheeled mobility devices differed with respect to age, gender, residential setting, and health-related factors among older adults. A total of 723 adults ageing 60 and older are representing three cohorts, from nursing homes, the Center for Assistive Technology, and the wheelchair registry from the Human Engineering Research Laboratories. Wheeled mobility devices were classified into three main groups: manual wheelchairs, power wheelchairs, and scooters. Our results found factors including age, gender, diagnosis, and living settings to be associated with differences in use of manual versus powered mobility devices. Differences in use were also noted for subtypes of manual (depot, standard, and customized) and powered (scooter, standard, and customized) mobility devices, on demographic, living arrangements, and health-related factors. Consideration of demographic, health-related, and environmental factors during the prescription process may help clinicians identify the most appropriate mobility device for the user.
Isolated Left Ventricular Noncompaction in a Case of Sotos Syndrome: A Casual or Causal Link?
Authors: Saccucci Patrizia , Papetti Federica , Martinoli Roberta , Dofcaci Alessandro , Tuderti Ursula , Marcantonio Andrea , Di Renzi Paolo , Fahim Asgharnejad , Ferrante Federica , Banci Maria
Published: June 2011

A 16-year-old boy affected by Sotos syndrome was referred to our clinic for cardiac evaluation in order to play noncompetitive sport. Physical examination was negative for major cardiac abnormalities and rest electrocardiogram detected only minor repolarization anomalies. Transthoracic echocardiography showed left ventricular wall thickening and apical trabeculations with deep intertrabecular recesses, fulfilling criteria for isolated left ventricular noncompaction (ILVNC). Some sporadic forms of ILVNC are reported to be caused by a mutation on CSX gene, mapping on chromosome 5q35. To our knowledge, this is the first report of a patient affected simultaneously by Sotos syndrome and ILVNC.
The Role of Epigenetic Alterations in Papillary Thyroid Carcinogenesis
Authors: Eze Ogechukwu P. , Starker Lee F. , Carling Tobias
Published: June 2011

Papillary thyroid carcinoma (PTC) accounts for over 80% of all thyroid malignancies. The molecular pathogenesis remains incompletely clarified although activation of the RET fusion oncogenes, and RAS and BRAF oncogenes, has been well characterized. Novel technologies using genome-wide approaches to study tumor genomes and epigenomes have provided great insights into tumor development. Growing evidence shows that acquired epigenetic abnormalities participate with genetic alterations to cause altered patterns of gene expression/function. It has been established beyond doubt that promoter cytosine methylation in CpG islands, and the subsequent gene silencing, is intimately involved in cancer development. These epigenetic events very likely contribute to significant variation in gene expression profiling, phenotypic features, and biologic characteristics seen in PTC. Hypermethylation of promoter regions has also been analyzed in PTC, and most studies have focused on individual genes or a small cohort of genes implicated in tumorigenesis.
Imaging-guided Parenchymal Liver Biopsy: How We Do It
Authors: Vijayaraghavan Gopal R , David Sheehan , Bermudez-Allende Myriam , Sarwat Hussain
Published: June 2011

Liver biopsies are performed for both focal and nonfocal lesions (parenchymal). In our center, majority of liver biopsies are performed for parenchymal liver disease. Parenchymal liver biopsy plays a key role in the diagnosis of various diffuse liver dysfunctions. Results of the biopsy help grade the disease, facilitating prognostication, which helps in planning specific treatment strategies. Imaging guidance is gaining wide acceptance as the standard procedure. Ultrasound (US) guidance is currently considered the most cost-effective and safe way to perform parenchymal liver biopsies. Radiologists worldwide and particularly in the United States are increasingly performing this procedure. Radiologists performing biopsies generally use the cutting needle. Different needle sizes, techniques and preference for biopsy of the right or left lobe have been described. We attribute these preferences to prior training and individual radiologist's comfort level. We describe the algorithm followed at our institution for performing percutaneous US-guided parenchymal liver biopsy. While clinical societies have recommended a minimum of 40 liver biopsies as a requirement for proficiency of clinicians, specific to radiology trainees/fellows interested in pursuing a career in intervention, we feel a total of 20 liver biopsies (includes assisted and independently performed biopsies under supervision) should be adequate training.
TNF-α and TNF-β Gene Polymorphism in Saudi Rheumatoid Arthritis Patients
Authors: Al-Rayes Hannan , Al-Swailem Ramiz , Albelawi Maysson , Arfin Misbahul , Al-Asmari Abdulrahman , Tariq Mohammad
Published: June 2011

Background

Tumor necrosis factor (TNF)-α and -β are cytokines with a wide range of inflammatory, apoptotic and immunomodulatory activities. TNF-α promoter –308 G < A polymorphism has been reported to be associated with rheumatoid arthritis (RA) with inconsistent results.

Objective

The aim of this study is to elucidate a possible association of TNF-α (G–308A) and TNF-β (A+252G) polymorphisms with the susceptibility of RA in Saudi patients.

Patients and Methods

This case control study consisted of 232 Saudi subjects including 106 RA patients and 126 matched controls. Genomic DNA was extracted using QIAampRDNA mini kit (Qiagen CA, USA). TNF-α and TNF-β genes were amplified using Arms primers.

Results

The frequencies of TNF-α (–308) allele G and genotype GG were significantly higher in RA patients as compared to controls while allele A and genotype AA were predominant in control group. On the other hand the frequency of TNF-β (+252) GG and AA genotypes were significantly higher in RA patients as compared to controls while GA genotype was predominant in controls. It was inferred that genotype GG positive individuals at position –308 of TNF-α were susceptible to RA while genotype AA might has a protective effect on RA susceptibility in Saudis. Whereas GG and AA genotype of TNF-β at +252 position might exert additive susceptibility to RA and GA might be refractory. However, there was no significant association between duration of morning stiffness, RF positivity and number of joints involved and distribution of alleles/genotypes of TNF-α (–308) or TNF-β (+252) polymorphism. It may be concluded that the TNF-α (–308) and TNF-β (+252) polymorphisms might influence the susceptibility to RA in Saudi population. These results might have prognostic value for future clinical observations.
Thyroxine and Free Thyroxine Levels in Workers Occupationally Exposed to Inorganic Lead
Authors: Bledsoe Michael L. , Pinkerton Lynne E. , Silver Sharon , Deddens James A. , Biagini Raymond E.
Published: June 2011

Background

The effects of lead exposure on thyroid function are unclear.

Methods

Serum thyroxine (T4) was evaluated among 137 lead-exposed workers and 83 non-exposed workers. Free thyroxine (FT4) was evaluated among a subset of these workers. Exposure metrics included blood lead level (BLL), which reflects recent exposure, zinc protoporphyrin (ZPP), a marker of intermediate-duration lead exposure, exposure duration, and estimated cumulative exposure. Multiple linear regression results were adjusted for age, race, and current smoking status.

Results

Mean BLLs were 38.9 μg/dL in lead exposed workers and 2.1 μg/dL in non-exposed workers. The adjusted mean T4 and FT4 concentrations among exposed and non-exposed workers were similar. While T4 was not significantly related to any of the exposure metrics, FT4 was inversely related to the logged values of both exposure duration and cumulative exposure, but not to ZPP or BLL.

Conclusions

The findings suggest that FT4 levels may be related to long-term lead exposure.
Constructions of Uniformly Convex Functions
Authors: Borwein Jonathan M. , Vanderwerff Jon
Published: June 2011

We give precise conditions under which the composition of a norm with a convex function yields a uniformly convex function on a Banach space. Various applications are given to functions of power type. The results are dualized to study uniform smoothness and several examples are provided.
Manifolds Covered by Lines and Extremal Rays
Authors: Novelli Carla , Occhetta Gianluca
Published: June 2011

Let X be a smooth complex projective variety, and let H ∈ Pic(X) be an ample line bundle. Assume that X is covered by rational curves with degree one with respect to H and with anticanonical degree greater than or equal to (dimX – 1)/2. We prove that there is a covering family of such curves whose numerical class spans an extremal ray in the cone of curves NE(X).
Ultraviolet actinic flux in clear and cloudy atmospheres: model calculations and aircraft-based measurements
Authors: Palancar G. G. , Shetter R. E. , Hall S. R. , Toselli B. M. , Madronich S.
Published: June 2011

Abstract. Ultraviolet (UV) actinic fluxes measured with two Scanning Actinic Flux Spectroradiometers (SAFS) aboard the NASA DC-8 aircraft are compared with the Tropospheric Ultraviolet-Visible (TUV) model. The observations from 17 days in July-August 2004 (INTEX-NA field campaign) span a wide range of latitudes (28° N–53° N), longitudes (45° W–140° W), altitudes (0.1–11.9 km), ozone columns (285–353 DU), and solar zenith angles (2°–85°). Both cloudy and cloud-free conditions were encountered. For cloud-free conditions, the ratio of observed to clear-sky-model actinic flux (integrated from 298 to 422 nm) was 1.01±0.04, i.e. in good agreement with observations. The agreement improved to 1.00±0.03 for the down-welling component under clear sky conditions. In the presence of clouds and depending on their position relative to the aircraft, the up-welling component was frequently enhanced (by as much as a factor of 8 relative to cloud-free values) while the down-welling component showed both reductions and enhancements of up to a few tens of percent. Including all conditions, the ratio of the observed actinic flux to the cloud-free model value was 1.1±0.3 for the total, or separately 1.0±0.2 for the down-welling and 1.5±0.8 for the up-welling components. The correlations between up-welling and down-welling deviations are well reproduced with sensitivity studies using the TUV model, and are understood qualitatively with a simple conceptual model. This analysis of actinic flux observations illustrates opportunities for future evaluations of photolysis rates in three-dimensional chemistry-transport models.
Uncertainty of the stratospheric/tropospheric temperature trends in 1979–2008: Multiple Satellite MSU, radiosonde, and reanalysis datasets
Authors: Xu J. ,   A. M. Powell Jr.
Published: June 2011

Abstract. The trends and spreads of tropospheric and stratospheric temperature are discussed in terms of three groups of datasets in 1979–2008. These datasets include (a) three satellite observations of Microwave Sounding Units (MSU) measurements, (b) five radiosonde observations and (c) five reanalysis products. The equivalent tropospheric and stratospheric temperature from radiosonde and reanalyses are calculated based on the vertical weighting function of the MSU channel 2 (CH2) and channel 4 (CH4) measurements, respectively. The results show that both cooling in the stratosphere and warming in troposphere significantly depends on the datasets and latitudes.
Emission controls versus meteorological conditions in determining aerosol concentrations in Beijing during the 2008 Olympic Games
Authors: Gao Y. , Liu X. , Zhao C. , Zhang M. , Wang Y.
Published: June 2011

Abstract. A series of emission control measures were undertaken in Beijing and the adjacent provinces in China during the 2008 Beijing Olympic Games on 8–24 August 2008. This provides a unique opportunity for investigating the effectiveness of emission controls on air pollution in Beijing. We conducted a series of numerical experiments over East Asia for the period of July to September 2008 using a coupled meteorology-chemistry model (WRF-Chem). Model can generally reproduce the observed variation of aerosol concentrations. Consistent with observations, modeled concentrations of aerosol species (sulfate, nitrate, ammonium, black carbon, organic carbon, total particulate matter) in Beijing were decreased by 30–50 % during the Olympic period compared to the other periods in July and August in 2008 and the same period in 2007. Model results indicate that emission controls were effective in reducing the aerosol concentrations by comparing simulations with and without emission controls. However, our analysis suggests that meteorological conditions (e.g., wind direction and precipitation) are at least as important as emission controls in producing the low aerosol concentrations appearing during the Olympic period. Transport from the regions surrounding Beijing determines the temporal variation of aerosol concentrations in Beijing. Based on the budget analysis, we suggest that to improve the air quality over Beijing, emission control strategy should focus on the regional scale instead of the local scale.
Information operator approach applied to the retrieval of the vertical distribution of atmospheric constituents from ground-based high-resolution FTIR measurements
Authors: Senten C. , De Mazière M. , Vanhaelewyn G. , Vigouroux C.
Published: June 2011

Abstract. The analysis of high spectral resolution Fourier Transform infrared (FTIR) solar absorption spectra is an important issue in remote sensing. If this is done carefully, one can obtain information, not only about the total column abundances, but also about the vertical distribution of various constituents in the atmosphere. This work introduces the application of the information operator approach for extracting vertical profile information from ground-based FTIR measurements. The algorithm is implemented and tested within the well-known retrieval code SFIT2, adapting the optimal estimation method such as to take into account only the significant contributions to the solution. In particular, we demonstrate the feasibility of the method in an application to ground-based FTIR spectra taken in the frame of the Network for the Detection of Atmospheric Composition Change (NDACC) at Ile de La Réunion (21° S, 55° E). A thorough comparison is made between the original optimal estimation method and this alternative retrieval algorithm, regarding information content, retrieval robustness and corresponding full error budget evaluation for the target species ozone (O3), nitrous oxide (N2O), methane (CH4), and carbon monoxide (CO). For O3 and CH4, a comparison with the Tikhonov regularization method has also been made. It is shown that the information operator approach performs well and in most cases yields both a better accuracy and stability than the optimal estimation method. Additionally, the information operator approach has the advantage of being less sensitive to the choice of a priori information. The Tikhonov regularization results seem to be situated between both methods' results, as to profile retrievals, error budgets and column stability.