bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of Mouse Adipose Tissue-Derived Stem Cells and Therapeutic Comparisons between Syngeneic and Allogeneic Adipose Tissue-Derived Stem Cell Transplantation in Experimental Autoimmune Thyroiditis
Authors: Choi Eun Wha , Shin Il Seob , Park So Young , Yoon Eun Ji , Kang Sung Keun , Ra Jeong Chan , Hong Sung Hwa
Published: March 2013

Previously, we found that the intravenous administration of human adipose tissue-derived mesenchymal stem cells was a promising therapeutic option for autoimmune thyroiditis even when the cells were transplanted into a xenogeneic model without an immunosuppressant. Therefore, we explored the comparison between the therapeutic effects of syngeneic and allogeneic adipose tissue-derived stem cells on an experimental autoimmune thyroiditis mouse model. Experimental autoimmune thyroiditis was induced in C57BL/6 mice by immunization with porcine thyroglobulin. Adipose tissue-derived stem cells derived from C57BL/6 mice (syngeneic) or BALB/c mice (allogeneic) or saline as a vehicle control were administered intravenously four times weekly. Blood and tissue samples were collected 1 week after the last transplantation. Adipose tissue-derived stem cells from mice were able to differentiate into multiple lineages in vitro; however, mouse adipose tissue-derived stem cells did not have immunophenotypes identical to those from humans. Syngeneic and allogeneic administrations of adipose tissue-derived stem cells reduced thyroglobulin autoantibodies and the inflammatory immune response, protected against lymphocyte infiltration into the thyroid, and restored the Th1/Th2 balance without any adverse effects. However, different humoral immune responses were observed for infused cells from different stem cell sources. The strongest humoral immune response was induced by xenogeneic transplantation, followed by allogeneic and syngeneic administration, in that order. The stem cells were mostly found in the spleen, not the thyroid. This migration might be because the stem cells primarily function in systemic immune modulation, due to being given prior to disease induction. In this study, we confirmed that there were equal effects of adipose tissue-derived stem cells in treating autoimmune thyroiditis between syngeneic and allogeneic transplantations.
Cold Storage of Rat Hepatocyte Spheroids
Authors: Liu Hongling , Yu Yue , Glorioso Jaime , Mao Shennen , Rodysil Brian , Amiot Bruce P. , Rinaldo Piero , Nyberg Scott L.
Published: March 2013

Cell-based therapies for liver disease rely on a high-quality supply of hepatocytes and a means for storage during transportation from site of isolation to site of usage. Unfortunately, frozen cryopreservation is associated with unacceptable loss of hepatocyte viability after thawing. The purpose of this study was to optimize conditions for cold storage of rat hepatocyte spheroids without freezing. Rat hepatocytes were isolated by a two-step perfusion method; hepatocyte spheroids were formed during 48 h of rocked culture in serum-free medium (SFM). Spheroids were then maintained in rocked culture at 37°C (control condition) or cold stored at 4°C for 24 or 48 h in six different cold storage solutions: SFM alone; SFM + 1 mM deferoxamine (Def); SFM + 1 μM cyclosporin A (CsA); SFM + 1 mM Def + 1 μM CsA, University of Wisconsin (UW) solution alone, UW + 1 mM Def. Performance metrics after cold storage included viability, gene expression, albumin production, and functional activity of cytochrome P450 enzymes and urea cycle proteins. We observed that cold-induced injury was reduced significantly by the addition of the iron chelator (Def) to both SFM and UW solution. Performance metrics (ammonia detoxification, albumin production) of rat hepatocyte spheroids stored in SFM + Def for 24 h were significantly increased from SFM alone and approached those in control conditions, while performance metrics after cold storage in SFM alone or cold storage for 48 h were both significantly reduced. A serum-free medium supplemented with Def allowed hepatocyte spheroids to tolerate 24 h of cold storage with less than 10% loss in viability and functionality. Further research is warranted to optimize a solution for extended cold storage of hepatocyte spheroids.
La province de Qaṭṭunân à l'époque de Zimrî-Lîm
Authors: Ziegler Nele
Published: March 2013

La province de Qaṭṭunân était, à l’époque des archives de Mari, une région pauvre et relativement peu peuplée. L’étude présente un survol des toponymes de cette province. Des hypothèses nouvelles de localisation sont faites en fonction des propositions récentes de retrouver Qirdahat dans la région de Hassake (D. Charpin, BBVO 20, p. 67-68) et Saggarâtum dans la région de Buseira (J.-M. Durand, BBVO 20, p. 50). Les toponymes sont énumérés par ordre géographique, du nord au sud, avec les localisations suivantes : Magrisâ (T. Tnenir ?) ; Ṭâbatum (T. Taban) ; Zilhân (sur la rive droite du Habur en face de T. Taban) ; Tehrân ou Tihrân (T. Hirbet Gamel ou éventuellement Tell Adjadja ?) ; Latihum (qui doit être cherchée sur la rive gauche du Habur dans la région de l’actuelle Rašidiya) ; Bît-Kapân (Tell Fiden ?) ; Râhatum (T. Abu Ha’iṭ). En dehors de la vallée du Habur se trouvait Dûr-ṣâbim qui doit être cherchée dans la steppe, à l’ouest du Habur. Le cas de la « Dêr » parfois surnommée « du Balih » est traité et sa localisation dans la région du Djebel Abd-al-Aziz est proposée.
Se réfugier à Ṭâbatum
Authors: Marti Lionel
Published: March 2013

Publication du fragment de lettre A.3318 datant du règne de Zimrî-Lîm et illustrant les difficultés que rencontra le roi de Mari pour organiser la région de Ṭâbatum, abandonnée par sa population. Celle-ci avait plus confiance en la steppe qu’en son suzerain pour la protéger des menaces alentours.
Le « pays de Mari et des Bédouins » à l'époque de Samsu-iluna de Babylone
Authors: Charpin Dominique
Published: March 2013

Cette étude s’interroge sur ce qu’est devenu le royaume de Zimri-Lim dans les décennies qui ont suivi la destruction du palais de Mari. Elle reprend l’examen de ce qu’on appelle souvent le « royaume de Hana » dans la première phase de son existence, sous les rois Yapah-Sumu-abum, Iṣi-Sumu-abum et Yadih-abum, contemporains du roi de Babylone Samsu-iluna. On tente d’abord de déterminer quels étaient l’extension géographique de ce royaume (de Harradum à Ṭabatum), son nom ( mât Hana  ?) et sa capitale (Terqa ? Mari ?). Suit l’analyse des nombreuses caractéristiques du royaume de Mari héritées par cette nouvelle unité politique : la continuité se marque par les titres de šâpiṭum et sugâgum , par des clauses dans les textes juridiques, par la permanence des mesure des capacités ( kur de 120 qa , ugârum ) ou des noms de mois. Cependant, la situation géo-politique avait assez fortement changé depuis la disparition de Zimri-Lim. Les archives découvertes à Tell Leilan ne parlent pas de ce royaume, car elles sont antérieures pour l’essentiel à l’an 8 de Samsu-iluna, date de la révolte qui donna naissance au nouvel État. On montre comment Samsu-iluna, entre l’an 22 et l’an 26, regagna du terrain aux dépens de celui-ci, mais sans réussir à le supprimer : la destruction de Tell Taban peut être datée de l’an 22 ou de l’an 27.
Le mahanum du dieu de l'orage
Authors: Durand Jean-Marie
Published: March 2013

La ville de Mahanum semble très abondamment documentée à Mari parce qu’elle apparaît souvent dans une formule de nom d’année qui parle de « Addu de Mahanum » ; en réalité « Mahanum » est mal attesté comme toponyme et ses localisations semblent contradictoires. En fait mahanum signifie « campement » et fait référence aux Mâr sim’al qui se déplaçaient sur une transversale est-ouest du Nord. Le fait que la mention de « Addu du mahanum  » se retrouve dans les documents de Ṭâbatum, à l’époque post-Mari, montre la survie de l’ethnie mâr sim’alite et de ses cultes dans ces régions.
Lesbian, Gay, Bisexual, and Transgender Health: Fundamentals for Nursing Education
Authors: Lim Fidelindo A. , Brown Donald V. , Jones Henrietta
Published: March 2013

As the health care needs of the lesbian, gay, bisexual, and transgender (LGBT) population become increasingly important, health care professionals require appropriate academic and clinical training in preparation for the increased demand for culturally competent care. Nurses are of particular interest, as they are the core direct caregivers in many health care settings. This article explores the national climate around LGBT individuals and their related health needs. Educators and administrators who work with future nurses should strive to ensure they foster the development of knowledgeable practitioners who will be able to implement best practices in LGBT patient care. Attention should be paid to providing students with diverse clinical placements, access to LGBT interest groups, and clear expectations for LGBT-sensitive nursing care plans and course outcomes selection that promote cultural competence. Recommendations for nursing education and curricular reform are discussed. [
J Nurs Educ.
2013;52(4):198–203.]
Variación en la explotación de la cuarcita durante el Paleolítico Superior en el Suroeste de la Península Ibérica
Authors: Pereira Telmo , Cascalheira João , Marreiros João , Almeida Francisco , Bicho Nuno
Published: March 2013

El Paleolítico Superior del Suroeste de la Península Ibérica está marcado por la presencia de conjuntos de cantos tallados y lascas en cuarcita. La caracterización detallada a nivel regional y cronológico de estos conjuntos es de la mayor importancia, ya que, en las fases más recientes del Paleolítico, se pueden encontrar sin asociación a fósiles-guía o depósitos datables. En este estudio, hemos utilizado 36 conjuntos de cuarcita de esa región para poner a prueba el carácter diagnóstico de esta materia prima a través de análisis de tributos y remontajes. Los resultados indican que Gravetiense, Solutrense y Magdaleniense se pueden distinguir en sus conjuntos de cuarcita, lo que permite, por sí mismo, la diferenciación de la secuencia clave del Paleolítico Superior. También indican que los conjuntos Gravetiense y Magdaleniense están tecnológicamente más próximos entre sí que respecto al Solutrense, un patrón posiblemente relacionado con la adaptación al Último Máximo Glaciar.
La plata de la Cultura de El Argar del Sur de la Península Ibérica: una primera aproximación a su producción y distribución
Authors: Bartelheim Martin , Contreras Cortés Francisco , Moreno Onorato Auxilio , Murillo-Barroso Mercedes , Pernicka Ernst
Published: March 2013

Se han documentado más de 700 objetos de plata de la cultura argárica del Bronce Medio. Esta cifra contrasta con la realidad del II milenio AC europeo, donde la plata es muy escasa. Esto se ha explicado tradicionalmente por la dificultad de extraer plata de minerales complejos mediante la técnica de copelación y la relativa abundancia de plata nativa y cloruros de plata fácilmente accesibles en el sur de la Península Ibérica. Sin embargo, hasta ahora, el uso de plata nativa en la Edad del Bronce ibérica se había deducido principalmente por la falta de evidencias de copelación. Los resultados de los análisis de elementos traza de una serie de objetos de plata de varios yacimientos argáricos suministran por primera vez una evidencia positiva del uso de plata nativa. Los análisis de isótopos de plomo demuestran que la mayoría de los objetos no procede de ninguno de los distritos mineros conocidos y caracterizados.
Procedencia de las puntas de jabalina del “Dolmen de la Pastora” (Valencina de la Concepción, Sevilla)
Authors: Hunt Ortiz Mark A. , Martínez Navarrete M. Isabel , Hurtado Pérez Víctor , Montero-Ruiz Ignacio
Published: March 2013

Este artículo combina una revisión bibliográfica actualizada y una nueva aproximación arqueométrica a las puntas de jabalina tipo La Pastora. Se incluyen recientes resultados del análisis por FRX e isótopos de plomo de ejemplares de este tipo metálico procedentes del “Dolmen de La Pastora” (Valencina de la Concepción, Sevilla) y del yacimiento de La Pijotilla (Badajoz), incorporando los datos de Outeiro de São Bernardo (Moura, Portugal). Las evidencias relacionadas con la interpretación arqueológica contextual de estos tres yacimientos permiten sugerir una fecha para las jabalinas tipo La Pastora en los siglos de transición entre el III y el II milenio a.C. Se confrontan los datos compositivos e isotópicos de las puntas de jabalina con otros elementos metálicos del ámbito regional y con las mineralizaciones caracterizadas isotópicamente en el suroeste de la Península Ibérica, además de con mineralizaciones y elementos metálicos del Mediterráneo oriental. Ello permite defender la producción ‘local’ de estas jabalinas en el suroeste peninsular, aunque con variaciones tipológicas regionales y a partir de fuentes minerales diversificadas.
Photolysis and Photocatalysis of 1,4 Dichlorobenzene Using Sputtered TiO2 Thin Films
Authors: Mahmoud Sawsan A. , Yassitepe Emre , Shah S. Ismat
Published: March 2013

The rate of 1,4-dichlorobenzene (1,4-DCB) degradation in the aqueous phase was investigated under direct photolysis or photocatalysis in the presence of TiO2 thin film prepared by reactive sputtering using a metal Ti target and a reaction sputtering atmosphere of argon and oxygen. The prepared thin films were analyzed by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). XPS confirmed the presence of completely oxidized TiO2 films whereas XRD showed that the films contained a mixture of rutile and anatase phases with rutile being approximately 30% of the total volume. Two lamps, both of the same power but different wavelength range were employed as irradiation sources. Photocatalysis showed faster removal of 1,4-DCB as compared to direct photolysis. The complete degradation was attained using the freshly prepared TiO2 sample. The intermediate produced during the photocatalysis was benzoquinone. Photolysis using visible irradiation was relatively slower and both benzoquinone and hydroquinone were formed as intermediates. Higher initial degradation rates were observed when the same film was re-used, most probably due to the effect of washing of the TiO2 thin films surface with methanol.
Photocatalytic Degradation of Organic Pollutants: A Review
Authors: Ameta Rakshit , Benjamin Surbhi , Ameta Aarti , Ameta Suresh C.
Published: March 2013

Water pollution is increasing at an ever increasing pace and the whole world is in the cancerous grip of this pollution. Various industries are discharging their untreated effluents into the nearby water resources; thus, adding to the existing water pollution to a great extent. Hence, there is a pressing demand to develop an alternate technology for wastewater treatment and in this context; photocatalysis has emerged as an Advanced Oxidation Process with green chemical approach for such a treatment. This chapter deals with photocatalytic degradation of different kinds of organic pollutants; mainly surfactants, pesticides, dyes, phenols, chloro compounds, nitrogen containing compounds etc. Mechanisms of their degradation have also been discussed with hydroxyl and allied radicals as the main active oxidizing species.
Degradation of Acid Red 27 in Sunlight Using TiO2
Authors: Kumar Jatinder , Bansal Ajay
Published: March 2013

The treatment of highly colored wastewater containing hazardous industrial chemicals and dyes is one of the growing needs of the present time. To meet the motive in the present work, TiO2 was immobilized on glass slides using heat method and acrylic binder. Heat method involves the preparation of suspension of powdered TiO2 and then brushing the suspension on the surface of glass slides. The slides were then calcined at high temperature for attachment of TiO2 to the glass surface. The acrylic binder method of immobilization involves preparation of acrylic emulsion and using the same to attach the TiO2 particles to the fiber glass slides. The preared films were then characterized using XRD and SEM. The photocatalytic performance of the prepared films for degradation of Acid Red 27 dye in sunlight was evaluated and compared. The films formed with the help of heat treatment method showed better dye degradation capabilities.
Preparation and Characterization of Li-Doped ZnO Nano-Sized Powders for Photocatalytic Applications
Authors: Ganesh Ibram , Sekhar P.S.C. , Padmanabham G. , Sundararajan G.
Published: March 2013

Different types of Li-doped ZnO (LDZ) (Li = 0 to 10%) powders were prepared by following a novel pyro-hydrolysis route at 450°C, and were thoroughly characterized by means of thermo-gravimetry (TG), differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, Fourier-transform Raman spectroscopy (FT-Raman), diffuse reflectance spectroscopy (DRS), ultra-violet visible (UV-vis.) spectroscopy, BET SA, and zeta potential (ζ) measurements. Photocatalytic activity of these powders was evaluated by means of methylene blue (MB) degradation experiments conducted under the irradiation of simulated and natural solar light. Characterization results suggest that both pure and LDZ powders are quite thermally stable up to a temperature of 700°C and possess band gap (BG) energies in the range of 3.16 to 3.2 eV with a direct band to band transition and ζ values of-31.6 mV to-56.4 mV. The properties exhibited by LDZ powders were found to be quite comparable to those exhibited byp-type semi-conducting LDZ powders. In order to study the kinetics of MB degradation reaction under the irradiation of simulated solar light, the Li (0.2 to 10%) and Al (0.5%) co-doped ZnO powders were also synthesized and employed for this purpose. The photocatalytic degradation of MB over Al and Li co-doped ZnO powders followed the Langmuir-Hinshelwood (L-H) first order reaction rate relationship. The 10% Li and 0.5% Al co-doped ZnO exhibited highest photocatalytic activity among various powders investigated in this study.
Superplastically Foaming Method for Reliable Porous Ceramics
Authors: Kishimoto Akira , Nakagawa Takahiro , Teranishi Takashi , Hayashi Hidetaka
Published: March 2013

Porous ceramics incorporates pores to improve several properties including thermal insulation, maintaining inherent ceramic properties such as corrosion resistance and large mechanical strength. Conventional porous ceramics is usually fabricated through an insufficient sintering, leading to degraded strength and durability. Contrary to this, we have innovated superplastically foaming method to make ceramic foam only in the solid state. In this method, the previously inserted foam agent evaporates after the full densification of matrix at around the sintering temperature. Closed pores expand utilizing the superplastic deformation driven by the evolved gas pressure. Based on this concept we fabricated 8mol% yttria stabirized zirconia based porous ceramics and examined the properties concerning the high temperature structural material with thermal insulation.
Superplasticity of Nb-Si-Fe and TiAl Intermetallics Synthesized by Powder Metallurgy
Authors: Zhang Kai Feng , Jiang Shao Song , Lu Zhen , Wang Guo Feng , Zhang Chun Ping , Yu Ji Liang
Published: March 2013

Nb-16Si-2Fe alloy were processed by mechanical alloying (MA) and hot pressing sintering (HPS). Microstructure analysis revealed the presence of four phases: Nb solid solution (Nbss), three kinds of intermetallics Nb3Si, Nb5Si3 and Nb4Fe3Si5. The maximum elongation over 500% was obtained at 1450°C and strain rate of 2.31×10-4s-1. TiAl powder pre-alloyed was carried out on pulse current sintering equipment (PCS) with high heating rate. The effect of heating rate on microstructures and high temperature ductility was investigated. The results show that relatively high heating rate is beneficial for obtaining fine grained microstructures. And the resultant intermetallic alloy with equiaxed near gamma structures exhibits superplasticity at relatively low temperature.
Superplastic Bulging of Nanocrystalline Ni-Co Alloy with Different Heating Methods
Authors: Wang Guo Feng , Jiang Shao Song , Lu Zhen , Zhang Kai Feng
Published: March 2013

Superplasticity of nanocrystalline materials is a hot spot in the field of scientific research. In this paper, Ni-Co alloy was produced through pulse electrodeposition. Tensile tests were carried out to study the room temperature strength, high temperature plasticity. The superplastic formability under complex stress was evaluated through the superplastic bulging tests. The tests were studied through the methods of resistance heating and furnace temperature heating. The maximum ratios of height and diameter with different heating method were compared. Fracture behavior and microstructure were observed by the method of SEM.
Inclination Angle Effect on the Thickness Distribution in a Superplastic Formed Long Rectangular Pan
Authors: Jarrar Firas Salah , Nazzal Mohammad Ahmad
Published: March 2013

In the superplastic process, the non-uniformity of the produced part thickness and the possibility of severe thinning are among the major disadvantages. This paper presents a parametric study on the superplastic forming of a Pb-Sn sheet into the shape of a long rectangular pan. A two dimensional plain strain finite element model was used to predict the forming times and thinning profiles of the formed Pb-Sn pan. The effect of varying the sidewall inclination angle was investigated for different friction conditions at the die-sheet interface. Results showed that increasing the side wall inclination angle reduced the forming time and provided a better thickness distribution.
Grain Boundary Sliding during Low Temperature Creep of Ultrafine and Coarse Grained Aluminum
Authors: Sato Eiichi , Ishiwata Kaoru , Matsunaga Tetsuya
Published: March 2013

HCP metals show new dislocation creep at temperatures below 0.3 Tm with stresses below σ0.2, while FCC metals show it above σ0.2. In the former, grain boundaries absorb the dislocations through slip-induced grain-boundary sliding, while in the latter dislocations are accommodated by cross slip at cell walls. The difference comes from the difference in the crystal symmetry. In UFG-Al at low temperatures, it is anticipated that grains without cell structure lead creep deformation similar to CG HCP metals rather than CG Al. UFG Al specimens were fabricated by ARB method. They showed remarkable creep behavior at less than σ0.2 similary to CG HCP metals. It posseses stress exponent of about three, grain-size exponent of almost zero, and very low apparent activation energy of 20 kJ/mol, and also grain boundary sliding behavior is obserbed by AFM.
A Time-Dependent Material Model for the Simulation of Hot Gas-Pressure Forming of Magnesium Alloy AZ31
Authors: Carpenter Alexander J. , Taleff Eric M. , Hector Louis G. , Carter Jon T. , Krajewski Paul E.
Published: March 2013

A time-dependent material constitutive model is developed for the deformation of wrought Mg AZ31 sheet material at 450°C. This material model is used to simulate gas-pressure bulge forming of AZ31 sheet into hemispherical domes. Finite-element-method (FEM) simulations using this material model are compared against experimental data obtained for dome height as a function of forming time under forming conditions identical to those assumed in the simulations. The time-dependent material model predicts experimental dome heights during forming with a quite useful accuracy. The most significant advantage of the time-dependent material model is that it can address the effect of preheating time on forming. Preheating times shorter than ~120 s produce an increase in forming rate. This material model provides a quantitative means of accounting for that effect.
Modeling the Super Plastic Forming of a Multi-Sheet Diffusion Bonded Titanium Alloy Demonstrator Fan Blade
Authors: Wood Paul , Qarni Muhammad Jawad , Blackwell Paul L. , Cerny Vladimir , Brennand Phillip , Wilkinson Steven , Rosochowski Andrzej
Published: March 2013

The paper describes a finite element method in 2D and 3D to simulate the super plastic forming of a demonstrator jet engine fan blade made from Titanium alloy sheet. The fan blade is an assembly of three sheets in which a single inner (core) sheet is diffusion bonded to the two outer (skin) sheets at prescribed zones, which is then super-plastically formed to a desired fan profile. In the model, the diffusion bonded zones between the core and skin sheets are simulated using tied interfaces. The thickness of each skin sheet is not uniform and significant change in thickness can occur over a short distance as well as gradually over the entire skin sheet. The thickness of the core sheet which is smaller than the thickness of each skin sheet remains uniform. The paper describes the design for a scaled-down demonstrator fan blade and model build process. Selected results and evaluations of finite element simulations are presented and discussed.
Instrumentation and Control of a Bulge Test on a Superplastic Pb-Sn Alloy
Authors: Petta Marinho Erick , Sakata Alberto , Fernanda Prados Erika , Ferreira Batalha Gilmar
Published: March 2013

Superplasticity is characterized by high elongations under a high strain rate sensibility, and it’s variation with strain rate, temperature and grain size. This parameter is often obtained from uniaxial tensile test. However, superplastic deformation is a biaxial process; hence there is a need to develop a way to get this parameter in a biaxial test. This work aims to set up the instrumentation to record and control a biaxial superplastic forming in a Pb-Sn alloy. The control system project has been divided into tracking variables: strain and pressure. The instrumentation is able to predict the breaking point at the beginning of the superplastic forming process from biaxial testing.
Finite Element Simulation for Superplastic Blow Forming of Toroidal Ti-6Al-4V Fuel Tank
Authors: Yoon Jong Hoon , Lee Ho Sung , Yi Yeng Moo , Yoo Joon Tae
Published: March 2013

In the current study, the finite element simulation for superplastic blow forming of a toroidal Ti-6Al-4V fuel tank is discussed. 3 types of preforms are investigated in order to obtain defect free final shape with desirable thickness distribution. From the simulation result, forming tool is designed so that the hydraulic pressure is not used. The forming test is carried out using forming pressure profile obtained from the simulation, and the validity of the selected perform is investigated in terms of thickness distribution and deformed shape.
A Robust Numerical Method for Validating Mesoscopic Grain Boundary Sliding Controlled Flow Model for Structural Superplasticity
Authors: Sripathi Sriharsha , Padmanabhan Anantha
Published: March 2013

Structural superplasticity is observed in materials of different classes with μm–, sub–μm– or nm– grain size. In all cases mesoscopic grain/interphase boundary sliding (~ grain diameter or more) is suggested to be the rate controlling mechanism. Sub–μm grained metallic and ceramic systems are analyzed here and good agreement with experimental results is established. Compared with earlier works, the numerical procedure is more robust and the free energy of activation for the rate controlling process is matched with the value for the same obtained using Eshelby’s equation.
Common Mechanism for Superplastic Deformation in Different Classes of Materials
Authors: Padmanabhan Anantha , Gleiter Herbert
Published: March 2013

An earlier proposal is generalized to explain superplasticity in different classes of materials and grain size ranges. A definition of “superplasticity” as due to a unique physical mechanism, rather than in terms of extreme elongations and/ or strain rate sensitivity index, m, being more than or equal to 0.30 emerges.
Extraordinary High Strain Rate Superplasticity of an Al-Mg-Sc-Zr Alloy Subjected to Equal Channel Angular Pressing
Authors: Avtokratova Elena , Sitdikov Oleg , Markushev Michael , Mulyukov Radik R.
Published: March 2013

Unique superplastic elongations up to 4100% were achieved at 450°C in the strain rate range of 10-2-10-1 s-1 for Al-Mg-Sc-Zr alloy with a grain size ~1 μm processed by warm-to-hot equal channel angular pressing. Such a behavior is attributed to the synergy of complementary factors resulted in high homogeneity and stability of ultrafine-grained microstructure and superplastic flow, involving large proportion of high-angle grain boundaries, presence of dispersoids of aluminides of transition metals and negligible amount of coarse excess phases.
Microstructure Control and Mechanical Properties of Multipass Friction Stir Processed High Strength Aluminum Alloy
Authors: Matsuda Yutaka , Itoh Goroh , Motohashi Yoshinobu
Published: March 2013

Friction stir processing (FSP) causes fine-equiaxed microstructure[1]. In this study, microstructure and mechanical properties of a 7075 aluminum alloy subjected to multipass FSP, MP-FSP, are assessed. A new zone, PBZ, has been discovered between stir zones, SZs. The SZs are composed of fine-equiaxed grains, while PBZs are composed of two types of (fine-equiaxed and coarse-elongated) grains, both of which are still finer than those of base metal. Elongation at 773K of MP-FSPed specimen becomes larger than that of base metal, based on superplastic deformation due to the finer microstructure. Local elongation is smaller in PBZ than in SZ.
EBSD Study of Microstructural Development during Superplastic-Like Forming
Authors: Liu Jun , Tan Ming Jen , Castagne Sylvie , Lim Samuel Chao Voon
Published: March 2013

Superplastic-like forming takes advantages of both deep drawing and bulge forming. The use of non-superplastic grade materials enables it to be more compatible with existing forming process with less material and time cost. Here, a non-isothermal heating system was adopted to selectively heat up selected localized areas to form the workpiece more efficiently. Electron backscattered diffraction (EBSD) was then used to investigate the wide range of grains in the formed samples resulting from elevated-temperature and large-strain deformation. The crystallographic textures of the material before and after deformation were observed for comparison. Very little recrystallization was found in the midst of the deformed grains. Considerable amount of elongated grains with high angle boundaries were produced during deformation. Many subgrain boundaries have developed within the big grains due to dynamic recovery.
Mechanical and Fatigue Properties of Titanium Alloy SP 700 after Simulated Superplastic Forming Conditions
Authors: Pitt Franna , Ramulu Mamidala
Published: March 2013

SP 700 is a relatively new titanium alloy with superplastic properties improved over the industry standard, Ti 6Al-4V. In order to use this alloy in structural applications following superplastic forming, the mechanical properties need to be well understood. This paper will present a summary of both static and fatigue properties of SP 700 following simulated SPF and post processed conditions, and compare them to Ti 6Al-4V
Pressure Profile Optimization on a Superplastic Aluminium Alloy
Authors: Sorgente Donato , Tricarico Luigi
Published: March 2013

In this work authors present a study of the influence of the pressure profile on forming time and on post-forming characteristics of superplastically formed parts. Material parameters of an aluminium superplastic alloy (ALNOVI-U) were estimated on the basis of experimental tests and of a numerical approach. A numerical model of the forming process was then created and used for evaluating the pressure profile able to keep the maximum strain rate value close to a target value. Pressure profiles were calculated using a strain rate control algorithm, firstly following a conventional approach and monitoring the whole sheet, and then considering only the elements most deformed at the end of the forming process. Experimental results from different numerical pressure profiles are then compared, in terms post-forming characteristics, to test the effectiveness of the approach.
Friction Stir Welding Combined with Superplastic Forming for Monolithic Titanium Aircraft Structure: Influence of Post Welding Thermal Treatments on Weld Nugget Residual Stress
Authors: Sanders Daniel G. , Ramulu Mamidala
Published: March 2013

This paper includes a review of the manufacturing technologies related to the combination of friction stir welding (FSW) and superplastic forming (SPF) to fabricate large monolithic titanium structures for aircraft. The particular focus is on the post FSW residual stress measured on the weld nugget after thermal treatments and SPF forming.
Innovative Superplastic Forming Based on In Situ Infra-Red Sheet Heating
Authors: Bernhart Gerard , Arcens Jean Paul , Le Maoult Yannick
Published: March 2013

This paper describes the research work that was performed in order to propose an innovative and low cost process route for superplastic forming of aluminum and titanium alloy sheets. The driving idea was to heat only the metallic sheet using heating elements included in the pressure chamber. Several heating configuration have been tested and equipment designs investigated. Based on experimental results and numerical thermal analysis, it was found that halogen heating lamps with a high reflective thermal insulation was the best for the upper pressure chamber, whereas low effusivity Refractory Castables materials seem optimal as low cost forming die. Energy consumption evaluation shows more than 80% energy saving in nominal titanium alloy forming. A pilot forming equipment was developed and first aluminum sheet forming trials give interesting results.
Characteristics of the GBS – SDC Transition during Bi-Axial Forming of AA5083
Authors: McNelley Terry , Oh Ishi Keiichiro , Swaminathan Srinivasan , Bradley John , Krajewski Paul , Taleff Eric M.
Published: March 2013

Thermomechanical processing to enable superplasticity in AA5083 materials includes cold working followed by heating prior to hot blow forming. Upon heating for forming at 450°C, a B-type ({110}) rolling texture is replaced by a near-random texture with a weak superimposed cube orientation parallel to the sheet normal. The presence of refined grains 7 – 8μm in size reflects the predominance of particle-stimulated nucleation of recrystallization prior to forming. The subsequent evolution of microstructure, texture and cavitation behaviour during biaxial deformation in the solute drag creep (SDC) and grain boundary sliding (GBS) regimes will be presented.
4D Damage Characterization during Superplastic Deformation of Magnesium Alloys
Authors: Lhuissier Pierre , Scheel Mario , Salvo Luc , Boller Elodie , Di Michiel Marco , Blandin Jean Jacques
Published: March 2013

As for aluminium alloys, magnesium alloys are generally sensitive to strain induced cavitation when they are deformed in superplastic conditions. It has been widely shown that X-ray micro tomography is a particularly efficient tool for studying in 3D damage mechanisms during superplastic deformation. However, such characterisations are generally performed in post mortem conditions, namely on samples first deformed up to given strains and then characterised. In the present investigation, thanks to particularly short acquisition times offered by ESRF, damage induced by superplastic deformation of a magnesium alloy is studied thanks to tomography analyses performed in 4D conditions, namely directly during high temperature deformation tests. Such conditions provide unique opportunities for investigating nucleation, growth and coalescence of cavities since it is thus possible to follow each cavity up to the fracture process.
Evaluation of Plastic Workability Limit of Magnesium Alloy by Cavitations in High Temperature Uni and Biaxial Test
Authors: Funami Kunio , Yamashita Daisuke , Suzuki Kohji , Noda Masafumi
Published: March 2013

Abstract. This study examined the critical plastic formability limit of a fine-structure AZ31 magnesium alloy plate under warm and high temperature based on the strength of a magnesium alloy that has cavities at room temperature. The cyclic hot free-forging process as pre-form working following rolling at a light reduction ratio fabricated a fine-structure AZ31 magnesium alloy plate. The appearance of the cavities was examined in detail together with changes in the structure and preparation methods before further damage at high temperatures with increasing uni-and biaxial plastic deformation. The allowable deformation limit in the super plasticity process can be estimated from the strength of the deformed material and forming limit diagram (FLD) at room temperature. During high-temperature deformation, cavities are produced by stress concentrations at grain boundary triple points and striation bands due to grain boundary sliding. The cavitations growth behavior is dependent upon deformation conditions, and a high percentage of large cavities occupy the sample surface as a large amount of grain boundary sliding is present, i.e., as uniform elongation grows larger, the cavity size also increases. In a case where 200% uniaxial strain was applied to a fine-grained structure material at a temperature of 623K under a strain rate of 10-4s-1, the tensile strength at room temperature decreased about 13%, and elongation was 10% less, compared with that of a material to which no load was applied due to the influence of cavities. In a case of biaxial deformation, the values were 28% lower. It is possible to draw a FLD based on the cavity incidence fraction .
Effect of Porosity on Tensile and Compressive Deformations of Superplastic Zn-22Al Alloy Foam
Authors: Kenji Sekido , Kitazono Koichi
Published: March 2013

Closed-cell Zn-22Al superplastic alloy foams were manufactured through the melt foaming process. The Zn-22Al foams were produced with varying porosity of 51-71%. The tensile and compressive properties of the Zn-22Al foams were investigated at 523 K. The compressive specimen has m-value of 0.55 in the low strain rate region. This is because of the superplastic deformation induced by the fine microstructure of the cell wall. Though the superplastic elongation was not obtained in high temperature tensile test, the elongation was higher than that of conventional aluminum foams.
Development of High-Strain-Rate Superplastic Oxide Ceramics Based on Flow Mechanism
Authors: Morita Koji , Kim Byung Nam , Yoshida Hidehiro , Sakka Yoshio , Hiraga Keijiro
Published: March 2013

In order to attain high-strain-rate superplasticity (HSRS) in ceramics, flow behavior was examined with ZrO2 reference sample. The results suggest that the enhancement of the accommodation processes of grain boundary sliding (GBS) is important in addition to the careful controlling the microstructural factors, such as stable fine grain structure, reducing residual pores and so on. The spinel particles dispersion can simultaneously provide the following positive factors to ZrO2: i) suppressed grain growth due to pinning effect of spinel particles, enhanced accommodation due to ii) accelerated relaxation of stress concentrations exerted by GBS through dislocation motion and iii) accelerated lattice diffusion caused by the dissolution of aluminum and magnesium into ZrO2 from the spinel particles. The positive factors due to spinel dispersion make it possible to attain HSRS in ZrO2 ceramics.
Exosome-like Nanoparticles from Intestinal Mucosal Cells Carry Prostaglandin E2 and Suppress Activation of Liver NKT Cells
Authors: Deng Zhong-Bin , Zhuang Xiaoying , Ju Songwen , Xiang Xiaoyu , Mu Jingyao , Liu Yuelong , Jiang Hong , Zhang Lifeng , Mobley James , McClain Craig , Feng Wenke , Grizzle William , Yan Jun , Miller Donald , Kronenberg Mitchell , Zhang Huang-Ge
Published: March 2013

Regulation and induction of anergy in NKT cells of the liver can inhibit autoimmune and antitumor responses by mechanisms that are poorly understood. We investigated the effects of PGE2, delivered by intestinal, mucus-derived, exosome-like nanoparticles (IDENs), on NKT cells in mice. In this study, we demonstrate that IDENs migrate to the liver where they induce NKT cell anergy. These effects were mediated by an IDENs’ PGE2. Blocking PGE2 synthesis attenuated IDENs inhibition of induction of IFN-γ and IL-4 by α-galactosylceramide (α-GalCer)–stimulated liver NKT cells in a PGE2 E-type prostanoid 2/E-type prostanoid 4 receptor–mediated manner. Proinflammatory conditions enhanced the migration of IDENs to the liver where α-GalCer and PGE2 induced NKT anergy in response to subsequent α-GalCer stimulation. These findings demonstrate that IDENs carrying PGE2 can be transferred from the intestine to the liver, where they act as immune modulators, inducing an anergic-like state of NKT cells. These reagents might be developed as therapeutics for autoimmune liver diseases.
Current Research Part A
Authors:   Geological Survey of Canada
Published: March 2013

Published literature describing the geology of the Canadian Arctic was examined relative to known attributes of shale-hosted lead-zinc deposits. Particular emphasis was placed on the search for evidence of depocentres, synsedimentary growth faults, and local
geothermal anomalies. In this manner, Franklinian Basin, Baffin Basin, and Foxe Fold Belt were recognized to contain particular . sedimentary formations favourable for the occurrence of shale-hosted lead-zinc deposits.
Stratigraphy of the Middle Cambrian platformal succession, southern Rocky Mountains
Authors: Aitken J D
Published: March 2013

The thick (1.3 km) and virtually complete Middle Cambrian platformal succession of the southern Rocky Mountains consists of four Grand Cycles, each beginning with a formation of the inner-detrital facies belt and ending with a formation of the middle carbonate
facies belt. The first three cycles, Mount Whyte/Cathedral, Stephen/Eldon, and Pika, share a common depositional style and are the main subject of this bulletin. The terminal, Arctomys/Waterfowl, cycle is of a distinctly different style and will be presented in a separate paper. Basinal equivalents
of the platformal formations, the lower and middle parts of the Chancellor Group, have not been studied in detail and receive only brief mention. The description of a terminal Lower Cambrian carbonate unit known as the Peyto and Hota formations, clarifies some Middle Cambrian problems. Dominant
influences on Middle Cambrian sedimentation in the region were the thermally subsiding Cordilleran Miogeocline; a hinge-line near the present mountain front;; a source of fine grained detritus to the north; and the Kicking Horse Rim, a persistent paleogeographic "high".
The Mount Whyte Formation is subdivided into two new members, the Weed and Chephren. The established Ross Lake Member, the new Trinity Lakes Member, and a wedge of deep-water carbonates, the Takakkaw Tongue, are recognized in the Cathedral Formation. The Takakkaw Tongue extends basinward from the
platform-margin reef. The Stephen Formation is subdivided into four new members, the Narao and Waputik members on the platform, and the Amiskwi and Wapta members in the basin. A tongue of outer detrital siliciclastic strata that penetrates the platform-margin shallow-water carbonates of the Eldon
Formation is formally recognized as the Field Member. One new member, the Tershishner Member, is recognized in the Pika Formation of the Front Ranges.
Formations and members of the Mount Whyte/Cathedral/Stephen succession are recognized only as members where they pass northward into the more shaly Snake Indian Formation. Outer-detrital (slope facies) equivalents of the Mount Whyte Formation are recognized as the Naiset
Formation.
Computational Small RNA Prediction in Bacteria
Authors: Sridhar Jayavel , Gunasekaran Paramasamy
Published: March 2013

Bacterial, small RNAs were once regarded as potent regulators of gene expression and are now being considered as essential for their diversified roles. Many small RNAs are now reported to have a wide array of regulatory functions, ranging from environmental sensing to pathogenesis. Traditionally, noncoding transcripts were rarely detected by means of genetic screens. However, the availability of approximately 2200 prokaryotic genome sequences in public databases facilitates the efficient computational search of those molecules, followed by experimental validation. In principle, the following four major computational methods were applied for the prediction of sRNA locations from bacterial genome sequences: (1) comparative genomics, (2) secondary structure and thermodynamic stability, (3) ‘Orphan’ transcriptional signals and (4) ab initio methods regardless of sequence or structure similarity; most of these tools were applied to locate the putative genomic sRNA locations followed by experimental validation of those transcripts. Therefore, computational screening has simplified the sRNA identification process in bacteria. In this review, a plethora of small RNA prediction methods and tools that have been reported in the past decade are discussed comprehensively and assessed based on their attributes, compatibility, and their prediction accuracy.
Assessing Healthcare Utilization for Influenza-like Illness at an Emergency Department and a Student Health Service during the 2009–2010 H1N1 Pandemic
Authors: Bhandari Ruchi , Hartley Tara A. , Lindsley William G. , Fisher Melanie A. , Palmer Jan E.
Published: March 2013

Estimates of healthcare utilization during an influenza pandemic are needed in order to plan for the allocation of staff and resources. The aim of this study was to assess the number, age, and arrival time of patients with influenza-like-illness (ILI), and associations between their symptoms during the 2009–2010 H1N1 pandemic. We conducted a cross-sectional analysis of electronic health records from the student health service (SHS) and an emergency department (ED) in Morgantown, West Virginia, between January 2009 and December 2010. During the 2009–2010 H1N1 pandemic, patient arrivals at SHS and ED varied over the week. SHS patients arrived early in the week and primarily in the afternoon. ED patient arrivals were more evenly distributed, with busier evenings and weekends. Those with fever were more likely to experience cough, sore throat, vomiting/nausea, chills, congestion, headache, and body-ache. These results can assist health professionals in preparing for an influenza pandemic.
Clinical Definitions of Melioidosis
Authors: Cheng Allen C. , Currie Bart J. , Dance David A. B. , Funnell Simon G. P. , Limmathurotsakul Direk , Simpson Andrew J. H. , Peacock Sharon J.
Published: March 2013

Clinical definitions of melioidosis and inhalation-acquired melioidosis (Burkholderia pseudomallei infection) are described together with the evidence used to develop these definitions. Such definitions support accurate public health reporting, preparedness planning for deliberate B. pseudomallei release, design of experimental models, and categorization of naturally acquired melioidosis.