bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical Analysis of Efficient Terahertz Difference Frequency Generation in Periodically-Inverted GaAs Crystals
Authors: Rao Zhi Ming , Xie Fang Sen , He Zhi Fang
Published: August 2014

This paper reports the analysis of efficient terahertz (THz) wave generation on the basis of quasi phase matching (QPM) difference frequency generation (DFG) in periodical GaAs by CO2laser. The efficient second-order nonlinear susceptibility of GaAs was calculated by similar to the calculation it of uniaxial crystal. We calculated second-order nonlinear susceptibility for the incidence two pump lights with the same propagation directions. The result shown that, the incidence two pump lights with the perpendicular polarization directions and the same polarization directions were efficient to obtain high power conversion efficiency of THz wave.
The Preparation and Test of Green Water-Based Metal Cleaning Agent
Authors: Zang Jian
Published: August 2014

A preparation of a kind of green water-based metal cleaning agent has been described in this paper. The reaction is using oleic acid and triethanolamine, by add the corresponding surface active agent. After a series of performance test, all kinds of metal has good corrosion resistance and cleaning effect, and no pollution to the environment.
Studies on the Chemical Constituents in the Essential Oil from the Leaves of Cinnamomum Bodinieri Levl
Authors: Luo Yong Ming , Luo Yong Dong , Chen Fang You , Liu Hua
Published: August 2014

Cinnamomum bodinieriLevl is a fast-growing species in tropical forests and widely distributed in southern China, Rich essential oil is in the leaves, which can be utilized as folk medicine. The chemical constituents of the essential oil obtained from the leaves ofCinnamomum bodinieriLevl were analyzed by GC-MS-DS. Sixty-three constituents were identified in the essential oils and the main constituents of the essential oils were terpinoids. The principal components are (content): camphor (40.81%), cineole (24.87 %), α-terpneol (8.75%), β-pinene (5.17 %), α-caryophyllene (2.17 %), caryophyllene (2.14 %), α-pinene (1.57 %), p-menth-1-en-4-ol (1.28 %), germacrene D (1.18 %).
Synthesis and Characterizations of Poly(Butylene Succinate) Copolyester
Authors: Liu Li , Cai Li Hai , Liu Dan , Xu Jun , Guo Bao Hua
Published: August 2014

The poly (butylene succinate) (PBS) and 3 wt% attapulgite (ATP) reinforced PBS/ATP nanocomposites with 1,6-hexanediol were fabricated using an in situ polymerization method. The crystallization behaviors indicated that ATP had effectively acted as nucleating agent, resulting in the enhancement on the crystallization temperature. The SEM results showed a superior interfacial linkage between ATP and PBS. Also, ATP could disperse as a single fiber and embed in the polymer matrix, which resulted in the improved mechanical properties.
Study of Porous Plate Hydrodynamic Cavitation Device for P-Nitrophenol
Authors: Deng Jie
Published: August 2014

Design a set of practical and effective hydraulic cavitation experiment device, hydraulic cavitation reactor, using porous plate for nitro phenol solution to simulate wastewater, respectively in different cavitation number initial pH value, initial concentration of the waste water, waste water, the cycle time, use different types of porous surface processing and analysis, through the experimental research, it is concluded that these factors and the relationship of nitro phenol degradation rate.
Study on Spin Transport Properties in Transition Metal Atoms Interfered Alpha-Graphyene Nanoribbon Systems
Authors: Zhou Y.H. , Zhou L.L. , Qiu X.H. , Peng Y.L.
Published: August 2014

The transport properties of transition metal atoms interfered alpha-graphyne nanoribbon systems are investigated by first-principles calculations combined with the Keldysh nonequilibrium Green’s method. In all, five types of configurations are considered. We find that intervention of three Cr atom in alpha-graphyne nanoribbon systems decreases the conductivity of the system. Further study show that the magnetic direction of the electrode infulence the spin filtering effect greatly, while the ralative magnetic direction of the three transition Cr atoms have little effect on the transport properties. At finite bias window, negative differential resistance happens. Proper analysis are given to explain the spin filtering phenonmenon and the different transport properties via transmission coefficient and projected density of states.
Rubidium and Cesium Recovery from Brine Resources
Authors: Zhang Nan , Gao Dao Lin , Liu Ming Ming , Deng Tian Long
Published: August 2014

In this paper, the methods for rubidium (Rb) and cesium (Cs) recovery from brines including salt lake brine, geothermal water and concentrated seawater were summarized, and the main problems existed were also pointed out. More details for Rb and Cs recovery from salt lake brines through fractional precipitation, ion exchange and solvent extraction were discussed, and the new trend for Rb and Cs recovery in the future were also carried out.
Progress in Research of the Combined Adsorption-Photocatalysis for the Removal of Volatile Organic Compounds
Authors: Lin Bo Tao , Shi Dong Mei , Li Tao , Meng Sen Kuan
Published: August 2014

TiO2photocatalytic technology was developed in the past two decades in air treatment because of good photocatalytic effect, non-toxic, chemical stability, low cost, reusable features, the effect use of solar energy. A new composite materials of visible light photocatalytic degradation of low concentration of volatile organic compounds were produced by use of combining the adsorbent with TiO2photocatalytic technology.The adsorbent can enrich concentrations of volatile organic compounds on the surface of the TiO2photocatalyst. In this paper,the mechanism of the combined adsorption-photocatalysis for the removal of volatile organic compounds and immobilization methods、principle、craft were reviewed.The characteristic of the immobilization methods was analysed.It laid the foundation for the optimizing of the immobilization methods and the improving of the photocatalytic efficiency.
Phase Equilibrium Study at 220°C of Li+,Mg2+//Cl-, SiO32--H2O Systerm
Authors: Ma Jun , Jia Yong Zhong , Jing Yan , Zhang Chao , Yao Ying , Sun Jin He
Published: August 2014

In this paper, phase equilibrium of Li+, Mg2+∥Cl-, SiO32--H2O system at 220°C was researched. The solid phases were characterized by X-ray diffraction (XRD). Lithium silicate, hectorite, karpinskite and magnesium hydroxide were observed as solid phases. According to the analysis of XRD, the phase diagram was obtained. The phase diagram could be used as the theoretical principle for synthesis of hectorite.
Synthesis of One Novel Thieno[2,3-D]Pyrimidine Derivative Bearing a Sulfonylurea Moiety
Authors: Chen Chen , Sun Cheng Yu , Xu Shan , Tu Yuan Biao , Zheng Peng Wu , Zhu Wu Fu
Published: August 2014

A novel thieno [2,3-d] pyrimidine compound (1) bearing a sulfonylurea moiety was synthesized from methyl 2-aminothiophene-3-carboxylate (2) through five steps including cyclization, chlorination, substitution with morpholine and piperazine, amidation and its structure was confirmed by 1H NMR and MS spectrum. The total yield of the five steps was 16.2% ( calculated from methyl 2-aminothiophene-3-carboxylate).
Integrated Hydraulic Bulge and Forming Limit Testing Method and Apparatus for Sheet Metals
Authors: Chen Yan Yo , Tsai Yu Chung , Huang Ching Hua
Published: August 2014

This paper proposes an integrated hydraulic bulge and forming limit testing method and apparatus for sheet metals. By placing a PU (Polyurethane) plate between molds and uniformly applying hydraulic pressure to sheet metals, a biaxial stress-strain relationship and forming limit diagram (FLD) displaying both left and right sides were acquired using the same apparatus. An uniaxial tension test and traditional drawing test were conducted to compare the results obtained from the proposed hydraulic bulge and forming limit testing methods, respectively. A close correlation between the results of the stress-strain relationship and FLD in both comparisons verified the feasibility and capability of this integrated hydraulic testing method and apparatus for use with sheet metals.
Study on Rotating Compression Forming of Double-Layer Clad Ring Considering Constant Shear Friction
Authors: Tzou Gow Yi , Hwang Yeong-Maw , Teng Hsiang Yu
Published: August 2014

This study establishes an analysis model based on the slab method assuming constant shear friction. The rotating compression forming of the double-layers bounded clad ring is derived by considering von Mises’ yield criterion with the shear stress. Effects of the frictional factor, shear yield stress ratio, rotating angular speed of the ring, frictional factor ratio, clad ring height ratio etc on compression characteristics are investigated effectively. Moreover, the compression pressure, radial stress for each layer, radial stress of the whole layer, and compression force are also predicted effectively. Finally, the FEM simulation is carried out to compare with the slab method to realize the variations of both models.
Molecular Dynamics Simulation on Transformation-Induced Plastic Deformation Using a Lennard-Jones Model
Authors: Uehara Takuya
Published: August 2014

Molecular dynamics simulations were carried out to clarify the atomistic mechanism of transformation plasticity. As the first step for the purpose, a simple thin-film model consisting of 8640 atoms was prepared. Phase transformation was assumed to be expressed by switching the material parameters of Lennard-Jones potential function. As a preliminary calculation, phase transformation was forced to occur homogeneously in the whole region of the model, resulting in no extra strain except volumetric transformation dilatation. In that case, perfect single crystal structure was maintained in the new phase. Simulations were carried out under external load, but specific strain was not generated. On the contrary, when the transformation region was set partially in the model and the region was expanded with time, a large deformation was observed. In the middle process of the phase transformation, slip-like deformation behavior and the change in crystal orientation occurred, indicating that extra plastic strain was induced during phase transformation. The strain was observed even when external load is not applied, and hence it was concluded that not only external load but also local stress distribution may cause the transformation plasticity.
Experimental Investigation of Transformation Plastic Behavior under Tensile-Compressive-Torsional Stress in Steel
Authors: Hikida Naoki , Yamamoto Yuta , Oshita Kenichi , Nagaki Shigeru
Published: August 2014

A tensile/compressive-torsional biaxial testing system was employed and tensile/ compressive-torsional tests were performed for the hollow specimen, which was loaded and the austenized specimen was cooled so that pealrite transformation accompanied by transformation plasticity occurred and axial and torsional strain were measured. Furthermore, the elastic-plastic constitutive equation due to phase transformation based on the hydrostatic pressure dependent model was proposed, and the validity of this equation was discussed experimentally. The test results showed the transformation plasticity coefficient due to pearlitic transformation of S45C depends on the loading direction, and these behaviour can be appropriately expressed by the hydrostatic pressure dependent model than the isotropic model.
Finite-Element Modeling of Thermal Forming of Ti-TWBs with Experimental Verification
Authors: Lai C.P. , Chan Luen Chow
Published: August 2014

The titanium tailor-welded blanks (Ti-TWBs) are being developed in different industries such as automobile and aerospace, combining the advantages of both tailor-welded blanks technology and titanium alloys. In recent decades, computer simulation of sheet metal forming processes has been employed increasingly over conventional production test and adjustment methodology to achieve the optimum and cost-effective operation procedures. Recently, certain amounts of theoretical analysis for the sheet metal forming process have been developed. However, these analyses could not be applied directly to the material under multi-stage forming process. Thus, some researchers have developed a damage-based model to predict the instability and failure of sheet metals, particularly for the above Ti-TWBs, with consideration of material damage under discontinuous or proportional loading strain paths. So far this model has been used and proved to be successful to predict formability of selected sheets of steel and aluminium alloy. However, the application of the damage-coupled model has yet to be extended to the Ti-TWBs under thermal multi-stage forming operation.The main objective of this paper is to investigate numerically the formability of Ti-TWBs under multi-stage forming process with experimental verification. Titanium alloy sheets (Ti-6Al-4V) in thickness of 0.7mm and 1.0mm were selected and laser-welded the specimen of Ti-TWBs. The model based on the damage mechanics is introduced to predict the thermal formability of Ti-TWBs with change of strain paths. In this study, the anisotropic damage model incorporate with the finite element codes and user-define material subroutine were developed to predict the formability of Ti-TWBs with change of strain paths. The mechanical properties and damage parameters of Ti-TWBs for the simulation were measured experimentally. The simulation of Ti-TWB under multi-stage forming process were then conducted and validated experimentally at similar forming conditions. The predicted results have been found to agree well with those obtained from the experiments. This analysis can be applied readily to design and manufacture TWB components or structures so as to satisfy the need of such market demands.
Behavior Identification of a Multi-Layered Graded Stainless Steel Using an Inverse Method
Authors: Shi Fei Fei , Hou Bing , Li Yu Long , Lu Jian , Zhao Han
Published: August 2014

The paper aimed at the behavior identification of a stainless steel sheet treated by surface mechanical attrition (SMAT). From tensile testing results on specimen after removing different depth of treated surface, a multi-layered model can be built. Therefore, the SMAT treated sheet is divided into five layers along thickness direction: the top and bottom hard layers of 0.15mm, the soft middle layer of 0.5mm, and two medium layers of 0.1mm in between. An elastic-plastic damageable constitutive model is adopted to describe the behavior of each layer. The parameters for each layer are identified using an inverse calculation technique. The three-dimensional ABAQUS/Explicit models with mass scaling are built for the SMAT treated tensile specimen with and without removed external harder layer. The best fit of parameters for each layer is obtained by minimizing the scatter between measured stress and calculated stress for the prescribed strain history. Finally, the identified material model is validated by the numerical simulation of a penetration test of SMAT treated sheet metal.
Effect of Porosity on Compressive Yield Strength of Microwave Sintered Titanium Components
Authors: Choy Man Tik , Tang Chak Yin
Published: August 2014

Titanium is widely used in biomedical implants because of its excellent mechanical properties, good biocompatibility and high resistance to corrosion. However, the fabrication of titanium components often involves high cost due to the long processing time and difficulty in metalworking. Powder metallurgy is a near-net-shape processing method which has the advantage of high production rate with low unit cost. In this study, a technique comprising microwave sintering with powder metallurgy has been developed to fabricate titanium components. Commercially pure titanium powdered compacts, prepared by three initial particle size groups of 10±2 μm, 30±2 μm, and 50±2 μm, were sintered in a 1.4 kW, 2.45 GHz microwave multi-mode furnace for 2 minutes using silicon carbide particles as the microwave susceptor to assist the heating. The room temperature deformation behavior of titanium components was investigated. Metallographic studies of the porosity and pore size were undertaken by optical microscopy. The results of this study indicate that irregular shaped pores were uniformly distributed within the sintered specimens. Furthermore, the pore size and porosity of the sintered specimens decrease with decreasing initial particle size. The compressive yield strength showed a linear relationship with the porosity, and was found to follow the Hall-Petch relationship with the initial particle size. This study demonstrated that it is feasible to microwave sinter titanium components having various compressive yield strengths by controlling the initial powder size of the titanium.
Effects of Silicon Carbide Proportion and Artificial Aging Parameters on Microstructure and Hardness of Al-Cu/SiCp Composites
Authors: Popescu Ileana Nicoleta , Vidu Ruxandra , Bratu Vasile , Olei Adrian Bebe , Ungureanu Dan Nicolae , Anghelina Florina Violeta
Published: August 2014

The purpose of these researches was to determine the effect of silicon carbide particles (SiCp) proportion and the effect of some process parameters (temperatures and times of aging) on characteristics of Al-Cu/SiCp composites obtained by P/M route. The age-hardened composites and un-reinforced alloys solution treated at 515 ± 5°C, maintaining time 360 minutes, quenched in water and artificial aging at 150-190o C during respectively 240-720 minutes/ furnace cooled, were tested from hardness and microstructural point of view. The effect of SiCp proportion in matrix during cold compaction was observed on densification curves of all experimental powders mixtures Al-4Cu/ (5, 10, 15 and 20) wt.%SiC. The composites were analyzed using optical and electron microscopy (including ESEM-Enviromental Scanning Electron Microscopy), in terms of shape and size of grains, pores, ceramic particles, second phases and precipitates.
Influence of Milling Time on the Homogeneity of the Al2O3/Ni Composite Powders Obtained by Mechanical Milling
Authors: Voicu Cristina , Popa Florin , Pascuta Petru , Chicinaş Ionel
Published: August 2014

Al2O3/Ni nanocomposite powder was obtained by high-energy mechanical milling starting from a mixture of Al2O3 and Ni commercially powders. The Al2O3+15%vol. Ni mixture was homogenized for 15 minutes in the Turbula-type blender and then was milled in a planetary ball mill (Fritsch, Pulverisette 4) under argon atmosphere up to 120 min. Several milling times were used: 10, 30, 60, 90 and 120 minutes respectively. The evolution of the powders during milling and the stability of the composite phases were investigated by X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis (EDX). The SEM and OM images show a high level of homogenization of the Ni and Al2O3 phases for milling times larger than 90 minutes. The X-ray studies indicate no mixing between the two phases. The crystallite grain size is decreasing with the milling time.
The Influence of the Sintering Temperature on the Wear Testing for Some Steels Samples Obtained by Powder Metallurgy
Authors: Olei Bebe Adrian , Ştefan Iulian , Popescu Nicoleta
Published: August 2014

The objective of this research is to observe the influence of the sintering temperature on the wear testing for some steel samples elaborated by powder metallurgy technology. For obtaining the steels there were used iron powders and graphite powders. The powders were homogenized in a high energy ball mill Pulverisette 6, cold compacted and then sintered in a furnace. The sintering parameters are: the sintering temperature, T = (1050, 1100, 1150)°C and the maintaining time, t = 60 minutes. The influence of the sintering parameters on the samples wear behavior is studied using both a tribometer and a profilometer.
Crystallization of Ni-Cr-Si-B and Ni-Cr-Fe-Si-B Amorphous Alloys
Authors: Codrean Cosmin , Buzdugan Dragoş , Lǎzar Ramona , Şerban Viorel Aurel , Mitelea Ion
Published: August 2014

Ni based amorphous alloys with Si and B, which can also, contains Fe and Cr, prepared by rapid solidification, have low melting temperatures. This fact increases their susceptibility to be joined by welding and brazing.
The glass forming ability (GFA) is conditioned also by the crystallization delay, due to certain chemical composition of the alloys.
The thermal stability of these alloys was revealed by DTA analysis and structural characteristics were investigated by XRD.
Applying an annealing at temperatures between 420°C and 540°C, with 30 minutes maintaining time, allowed the investigation of phase occurred during the crystallization and the estimation of the crystalline grains dimensions.
Influence of the Si-Content on the High Temperature Oxidation Behaviour of NiCrBSi-Coatings
Authors: Strübbe Carsten , Marginean Gabriela , Serban Viorel Aurel
Published: August 2014

The high temperature oxidation behaviour of Ni-Cr-B-Si coatings with a higher Si-content was investigated in order to evaluate the suitability of such materials especially for novel applications concerning highly aggressive environments like metal dusting. Metal dusting is a corrosion phenomenon that occurs in reducing-, carbon-supersaturated (ac>1) gaseous atmosphere, containing CO, H2, CO2 and H2O, at elevated temperatures between 400 and 800°C. Metal dusting reactions can be classified into two types. The first one concerns Fe-alloys, where Fe3C is growing on the surface. The second one is related to the reaction of Ni, Co and their alloys, where the destruction takes place through inward growth or direct ingrowth of graphite, without forming the metastable Fe3C. Regarding to the literature, metal dusting is typically encountered in industrial furnaces, but mainly in the chemical or petrochemical industry. The way to suppress metal dusting is to stop the dissociation of the carbon source or to stop the carbon ingress in the material. One possibility in order to avoid the carburization of Fe, Ni, Co and their alloys is to preoxidize the samples. Based on the reducing atmosphere, where metal dusting occurs, the isothermal outsourcing for the formation of a protective Al-, Cr- or Si-oxide layer on the samples in air is mostly necessary. The role of a stable Al2O3 and Cr2O3-layer on the sample as a diffusion barrier against the carbon ingress, based on their low solubility for carbon, has already been investigated and proved by many scientists. The formation of a protective and thermodynamically very stable SiO2 scale was also investigated. Within the scope of this work, the influence of a higher Si-content (4,5 wt%) in NiCrBSi-alloys, depending on the temperature, was analyzed. For this purpose the samples were oxidized in air at 600, 700 and 800°C respectively. The surface morphology and the phase composition of the grown oxide scales were characterized by means of scanning electron microscopy combined with energy dispersive X-ray (SEM/EDX) and by X-ray diffraction (XRD) technique. The experimental results demonstrate the importance of silicon content on the coatings properties, respectively on the stability of the formed oxide scale (free of micro cracks, no spallation). This element is able to form beside chromium, a dense oxide layer on the sample surface, protecting it against further degradation induced by the atmosphere in different high temperature applications. Moreover, the increased chromium content of the feedstock powder (from 10 wt% in previous work to 12,5 wt%) demonstrated that the Ni-Cr-B-Si coatings exposed at 600°C, 700°C as well as at 800°C were not susceptible to internal oxidation.
The Ataxia Telangiectasia Mutated and Cyclin D3 Proteins Cooperate To Help Enforce TCRβ and IgH Allelic Exclusion
Authors: Steinel Natalie C. , Fisher Megan R. , Yang-Iott Katherine S. , Bassing Craig H.
Published: August 2014

Coordination of V rearrangements between loci on homologous chromosomes is critical for Ig and TCR allelic exclusion. The Ataxia Telangietasia mutated (ATM) protein kinase promotes DNA repair and activates checkpoints to suppress aberrant Ig and TCR rearrangements. In response to RAG cleavage of Igκ loci, ATM inhibits RAG expression and suppresses further Vκ-to-Jκ rearrangements to enforce Igκ allelic exclusion. Because V recombination between alleles is more strictly regulated for TCRβ and IgH loci, we evaluated the ability of ATM to restrict biallelic expression and V-to-DJ recombination of TCRβ and IgH genes. We detected greater frequencies of lymphocytes with biallelic expression or aberrant V-to-DJ rearrangement of TCRβ or IgH loci in mice lacking ATM. A preassembled DJβ complex that decreases the number of TCRβ rearrangements needed for a productive TCRβ gene further increased frequencies of ATM-deficient cells with biallelic TCRβ expression. IgH and TCRβ proteins drive proliferation of prolymphocytes through cyclin D3 (Ccnd3), which also inhibits VH transcription. We show that inactivation of Ccnd3 leads to increased frequencies of lymphocytes with biallelic expression of IgH or TCRβ genes. We also show that Ccnd3 inactivation cooperates with ATM deficiency to increase the frequencies of cells with biallelic TCRβ or IgH expression while decreasing the frequency of ATM-deficient lymphocytes with aberrant V-to-DJ recombination. Our data demonstrate that core components of the DNA damage response and cell cycle machinery cooperate to help enforce IgH and TCRβ allelic exclusion and indicate that control of V-to-DJ rearrangements between alleles is important to maintain genomic stability.
The Late Endosomal Transporter CD222 Directs the Spatial Distribution and Activity of Lck
Authors: Pfisterer Karin , Forster Florian , Paster Wolfgang , Supper Verena , Ohradanova-Repic Anna , Eckerstorfer Paul , Zwirzitz Alexander , Donner Clemens , Boulegue Cyril , Schiller Herbert B. , Ondrovičová Gabriela , Acuto Oreste , Stockinger Hannes , Leksa Vladimir
Published: August 2014

The spatial and temporal organization of T cell signaling molecules is increasingly accepted as a crucial step in controlling T cell activation. CD222, also known as the cation-independent mannose 6-phosphate/insulin-like growth factor 2 receptor, is the central component of endosomal transport pathways. In this study, we show that CD222 is a key regulator of the early T cell signaling cascade. Knockdown of CD222 hampers the effective progression of TCR-induced signaling and subsequent effector functions, which can be rescued via reconstitution of CD222 expression. We decipher that Lck is retained in the cytosol of CD222-deficient cells, which obstructs the recruitment of Lck to CD45 at the cell surface, resulting in an abundant inhibitory phosphorylation signature on Lck at the steady state. Hence, CD222 specifically controls the balance between active and inactive Lck in resting T cells, which guarantees operative T cell effector functions.
Differences in the Transduction of Canonical Wnt Signals Demarcate Effector and Memory CD8 T Cells with Distinct Recall Proliferation Capacity
Authors: Boudousquié Caroline , Danilo Maxime , Pousse Laurène , Jeevan-Raj Beena , Angelov Georgi S. , Chennupati Vijaykumar , Zehn Dietmar , Held Werner
Published: August 2014

Protection against reinfection is mediated by Ag-specific memory CD8 T cells, which display stem cell–like function. Because canonical Wnt (Wingless/Int1) signals critically regulate renewal versus differentiation of adult stem cells, we evaluated Wnt signal transduction in CD8 T cells during an immune response to acute infection with lymphocytic choriomeningitis virus. Whereas naive CD8 T cells efficiently transduced Wnt signals, at the peak of the primary response to infection only a fraction of effector T cells retained signal transduction and the majority displayed strongly reduced Wnt activity. Reduced Wnt signaling was in part due to the downregulation of Tcf-1, one of the nuclear effectors of the pathway, and coincided with progress toward terminal differentiation. However, the correlation between low and high Wnt levels with short-lived and memory precursor effector cells, respectively, was incomplete. Adoptive transfer studies showed that low and high Wnt signaling did not influence cell survival but that Wnt high effectors yielded memory cells with enhanced proliferative potential and stronger protective capacity. Likewise, following adoptive transfer and rechallenge, memory cells with high Wnt levels displayed increased recall expansion, compared with memory cells with low Wnt signaling, which were preferentially effector-like memory cells, including tissue-resident memory cells. Thus, canonical Wnt signaling identifies CD8 T cells with enhanced proliferative potential in part independent of commonly used cell surface markers to discriminate effector and memory T cell subpopulations. Interventions that maintain Wnt signaling may thus improve the formation of functional CD8 T cell memory during vaccination.
The Expression of Sphingosine-1 Phosphate Receptor-1 in Chronic Lymphocytic Leukemia Cells Is Impaired by Tumor Microenvironmental Signals and Enhanced by Piceatannol and R406
Authors: Borge Mercedes , Remes Lenicov Federico , Nannini Paula R. , de los Ríos Alicandú María M. , Podaza Enrique , Ceballos Ana , Fernández Grecco Horacio , Cabrejo María , Bezares Raimundo F. , Morande Pablo E. , Oppezzo Pablo , Giordano Mirta , Gamberale Romina
Published: August 2014

Chronic lymphocytic leukemia (CLL) is characterized by the progressive accumulation of clonal B lymphocytes. Proliferation occurs in lymphoid tissues upon interaction of leukemic cells with a supportive microenvironment. Therefore, the mobilization of tissue-resident CLL cells into the circulation is a useful therapeutic strategy to minimize the reservoir of tumor cells within survival niches. Because the exit of normal lymphocytes from lymphoid tissues depends on the presence of sphingosine-1 phosphate (S1P) and the regulated expression of S1P receptor-1 (S1PR1), we investigated whether the expression and function of S1PR1 can be modulated by key microenvironment signals. We found that activation of CLL cells with CXCL12, fibroblast CD40L+, BCR cross-linking, or autologous nurse-like cells reduces their S1PR1 expression and the migratory response toward S1P. Moreover, we found that S1PR1 expression was reduced in the proliferative/activated subset of leukemic cells compared with the quiescent subset from the same patient. Similarly, bone marrow–resident CLL cells expressing high levels of the activation marker CD38 showed a lower expression of S1PR1 compared with CD38low counterparts. Finally, given that treatment with BCR-associated kinase inhibitors induces a transient redistribution of leukemic cells from lymphoid tissues to circulation, we studied the effect of the Syk inhibitors piceatannol and R406 on S1PR1 expression and function. We found that they enhance S1PR1 expression in CLL cells and their migratory response toward S1P. Based on our results, we suggest that the regulated expression of S1PR1 might modulate the egress of the leukemic clone from lymphoid tissues.
Role of TGF-β Signaling in Generation of CD39+CD73+ Myeloid Cells in Tumors
Authors: Ryzhov Sergey V. , Pickup Michael W. , Chytil Anna , Gorska Agnieszka E. , Zhang Qinkun , Owens Philip , Feoktistov Igor , Moses Harold L. , Novitskiy Sergey V.
Published: August 2014

There is growing evidence that generation of adenosine from ATP, which is mediated by the CD39/CD73 enzyme pair, predetermines immunosuppressive and proangiogenic properties of myeloid cells. We have previously shown that the deletion of the TGF-β type II receptor gene (Tgfbr2) expression in myeloid cells is associated with decreased tumor growth, suggesting protumorigenic effect of TGF-β signaling. In this study, we tested the hypothesis that TGF-β drives differentiation of myeloid-derived suppressor cells into protumorigenic terminally differentiated myeloid mononuclear cells (TDMMCs) characterized by high levels of cell-surface CD39/CD73 expression. We found that TDMMCs represent a major cell subpopulation expressing high levels of both CD39 and CD73 in the tumor microenvironment. In tumors isolated from mice with spontaneous tumor formation of mammary gland and conditional deletion of the type II TGF-β receptor in mammary epithelium, an increased level of TGF-β protein was associated with further increase in number of CD39+CD73+ TDMMCs compared with MMTV-PyMT/TGFβRIIWT control tumors with intact TGF-β signaling. Using genetic and pharmacological approaches, we demonstrated that the TGF-β signaling mediates maturation of myeloid-derived suppressor cells into TDMMCs with high levels of cell surface CD39/CD73 expression and adenosine-generating capacity. Disruption of TGF-β signaling in myeloid cells resulted in decreased accumulation of TDMMCs, expressing CD39 and CD73, and was accompanied by increased infiltration of T lymphocytes, reduced density of blood vessels, and diminished progression of both Lewis lung carcinoma and spontaneous mammary carcinomas. We propose that TGF-β signaling can directly induce the generation of CD39+CD73+ TDMMCs, thus contributing to the immunosuppressive, proangiogenic, and tumor-promoting effects of this pleiotropic effector in the tumor microenvironment.
Idiotype-Specific Th Cells Support Oligoclonal Expansion of Anti-dsDNA B Cells in Mice with Lupus
Authors: Aas-Hanssen Kristin , Funderud Ane , Thompson Keith M. , Bogen Bjarne , Munthe Ludvig A.
Published: August 2014

Systemic lupus erythematosus (SLE) is marked by a Th cell–dependent B cell hyperresponsiveness, with frequent germinal center reactions and hypergammaglobulinemia. The specificity of Th cells in lupus remains unclear, but B cell Ids have been suggested. A hallmark is the presence of anti-dsDNA, mutated IgG autoantibodies with a preponderance of arginines in CDR3 of the Ig variable H chain (IgVH). B cells can present V region–derived Id peptides on their MHC class II molecules to Id-specific Th cells. We show that Id-specific Th cells support the proliferation of anti-dsDNA Id+ B cells in mice suffering from systemic autoimmune disease with SLE-like features. Mice developed marked clonal expansions of B cells; half of the IgVH sequences were clonally related. Anti-dsDNA B cells made up 40% of B cells in end-stage disease. The B cells expressed mutated IgVH with multiple arginines in CDR3. Hence, Id-driven T cell–B cell collaboration supported the production of classical anti-dsDNA Abs, recapitulating the characteristics of such Abs in SLE. The results support the concept that Id-specific Th cells may trigger the development of SLE and suggest that manipulation of the Id-specific T cell repertoire could play a role in treatment.
Concomitant TLR/RLH Signaling of Radioresistant and Radiosensitive Cells Is Essential for Protection against Vesicular Stomatitis Virus Infection
Authors: Spanier Julia , Lienenklaus Stefan , Paijo Jennifer , Kessler Annett , Borst Katharina , Heindorf Sabrina , Baker Darren P. , Kröger Andrea , Weiss Siegfried , Detje Claudia N. , Staeheli Peter , Kalinke Ulrich
Published: August 2014

Several studies indicated that TLR as well as retinoic acid–inducible gene I–like helicase (RLH) signaling contribute to vesicular stomatitis virus (VSV)–mediated triggering of type I IFN (IFN-I) responses. Nevertheless, TLR-deficient MyD88−/−Trif−/− mice and RLH-deficient caspase activation and recruitment domain adaptor inducing IFN-β (Cardif)−/− mice showed only marginally enhanced susceptibility to lethal VSV i.v. infection. Therefore, we addressed whether concomitant TLR and RLH signaling, or some other additional mechanism, played a role. To this end, we generated MyD88−/−Trif−/−Cardif−/− (MyTrCa−/−) mice that succumbed to low-dose i.v. VSV infection with similar kinetics as IFN-I receptor–deficient mice. Three independent approaches (i.e., analysis of IFN-α/β serum levels, experiments with IFN-β reporter mice, and investigation of local IFN-stimulated gene induction) revealed that MyTrCa−/− mice did not mount IFN-I responses following VSV infection. Of note, treatment with rIFN-α protected the animals, qualifying MyTrCa−/− mice as a model to study the contribution of different immune cell subsets to the production of antiviral IFN-I. Upon adoptive transfer of wild-type plasmacytoid dendritic cells and subsequent VSV infection, MyTrCa−/− mice displayed significantly reduced viral loads in peripheral organs and showed prolonged survival. On the contrary, adoptive transfer of wild-type myeloid dendritic cells did not have such effects. Analysis of bone marrow chimeric mice revealed that TLR and RLH signaling of radioresistant and radiosensitive cells was required for efficient protection. Thus, upon VSV infection, plasmacytoid dendritic cell–derived IFN-I primarily protects peripheral organs, whereas concomitant TLR and RLH signaling of radioresistant stroma cells as well as of radiosensitive immune cells is needed to effectively protect against lethal disease.
The N-Terminal Domain of NLRC5 Confers Transcriptional Activity for MHC Class I and II Gene Expression
Authors: Neerincx Andreas , Jakobshagen Kristin , Utermöhlen Olaf , Büning Hildegard , Steimle Viktor , Kufer Thomas A.
Published: August 2014

Ag presentation to CD4+ and CD8+ T cells depends on MHC class II and MHC class I molecules, respectively. One important regulatory factor of this process is the transcriptional regulation of MHC gene expression. It is well established that MHC class II transcription relies on the NLR protein CIITA. Recently, another NLR protein, NLRC5, was shown to drive MHC class I expression. The molecular mechanisms of the function of NLRC5 however remain largely elusive. In this study, we present a detailed functional study of the domains of NLRC5 revealing that the N-terminal domain of human NLRC5 has intrinsic transcriptional activity. Domain swapping experiments between NLRC5 and CIITA showed that this domain contributes to MHC class I and MHC class II gene expression with a bias for activation of MHC class I promoters. Delivery of this construct by adeno-associated viral vectors upregulated MHC class I and MHC class II expression in human cells and enhanced lysis of melanoma cells by CD8+ cytotoxic T cells in vitro. Taken together, this work provides novel insight into the function of NLRC5 and CIITA in MHC gene regulation.
Representation Stability of Power Sets and Square Free Polynomials
Authors: Ashraf Samia , Azam Haniya , Berceanu Barbu
Published: August 2014

The symmetric group 𝓢n acts on the power set 𝓟(n) and also on the set of square free polynomials in n variables. These two related representations are analyzed from the stability point of view. An application is given for the action of the symmetric group on the cohomology of the pure braid group.
Marketing Education in Light of Catholic Social Teaching
Authors: Rankin Jeff ,   Society of Catholic Social Scientists
Published: August 2014

This paper explores how several fundamental concepts from Catholic Social Teaching (CST) and other Christian thought can be integrated with the marketing curriculum at a Catholic university in the spirit of Ex Corde Ecclesiae and Fides et Ratio with an aim to equip students to become ethical business leaders. The paper also discusses some initial pedagogical approaches and some brief student feedback.
Pope Pius XII: About Those Archives
Authors: Rychlak Ronald J. ,   Society of Catholic Social Scientists
Published: August 2014

Questions about Pope Pius XII’s leadership during World War II continue to color Catholic-Jewish relations. While many scholars have engaged in research on the topic, a growing number argue that no conclusions can be reached until all relevant Vatican archives have been opened and reviewed. This paper argues that currently open Vatican archives, supplemented with eyewitness accounts and documents from other sources, provide a consistent portrait of the wartime pope as a champion of the victims, opponent of the villains, and inspiration to the rescuers. As such, even without opening additional archives, the documentary record supports the Holy See’s determination that Pius XII led a life of “heroic virtue.”
Profit Maximization and the Subjective Dimension of Work
Authors: O’Boyle Edward J. ,   Society of Catholic Social Scientists
Published: August 2014

To be consistent with John Paul II’s assertion of the primacy of the subjective dimension of work—of “being” versus “having”—it is necessary to reject profit maximization as the primary objective of the firm. In its place, the author proposes instead that the firm’s foremost objective is the maximization of personalist capital. Properly understood, profits are a necessary condition for the firm’s survival but not its primary goal. The concept of personalist capital in effect incorporates the subjective dimension of work into microeconomic theory without dismissing the objective dimension entirely.
Constitutionalism in Burke’s Reflections as Critique of the Enlightenment Ideas of Originative Political Consent and the Social Compact
Authors: Almeida Joseph ,   Society of Catholic Social Scientists
Published: August 2014

Burke’s Reflections on the Revolution in France is an anti-Enlightenment tract. His treatment therein of the British constitution (and constitutionalism in general) is set in critical opposition to the Enlightenment philosophical principles that animated the French Revolution. However, he often employs the very terms of Enlightenment political theory in framing his criticisms of Enlightenment principles. The solution to this interpretive problem is that Burke purposefully employed Enlightenment terminology in the Reflections precisely to signal his specific intention to criticize the key Enlightenment notion of political consent and to transform the Enlightenment theory of social compact into a theory of constitutionalism, understood as the generational transmission of prescriptive political institutions. Proof comes through a reading of the Reflections limited by the parameters of the problem of interpretation, which in turn indicates some general aspects of a Burkean theory of the political and social order.
The Freedom of the Church and the Taming of Leviathan: The Christian Revolution, Dignitatis Humanae, and Western Liberty
Authors: Grasso Kenneth L. ,   Society of Catholic Social Scientists
Published: August 2014

This essay explores the impact of the ancient principle of the freedom of the Church—identified by the Second Vatican Council as “the fundamental principle” governing “the relations between the Church and governments and the whole civil order”—on both Western civilization and the development of modern Catholic social thought. Arguing that this principle requires the articulation and institutionalization of a new understanding of society and government, it contends this principle revolutionized the structure of Western political life and helped lay the groundwork for Western liberty. At the same time, it maintains that the development in contemporary Catholic social teaching that crystallizes in Dignitatis Humanae must be seen in the context of the ongoing effort of Catholic thought to understand the nature and role of the state towards which the idea of the freedom of the Church points.
A Retrospective on Public Policy Threats to Religious Liberty in the Workplace
Authors: Kelly Eileen P. , Kelly Thomas E. ,   Society of Catholic Social Scientists
Published: August 2014

Catholic employers and employees have been under increasing attack in the last fifty years by a growing number of public policy encroachments in the workplace that are in direct conflict with their religious convictions. In some instances, these threats have been successfully parried. Others remain a source of serious conflict. This article will summarize highlights of the last fifty years of public policy and jurisprudence as they relate to the ability of Catholic institutions to practice and enforce non-negotiable Catholic moral doctrines.
Tocqueville on Christianity and the Natural Equality of Man
Authors: Rahe Paul A. ,   Society of Catholic Social Scientists
Published: August 2014

Democracy in America never mentions the Declaration of Independence. Is this perhaps a sign of hostility to the Declaration’s natural-rights teaching or to abstract principles? Or is it no more significant than The Federalist’s silence on this matter? Both are books of political science, not political philosophy; yet, when appropriate, Tocqueville addresses first principles, and endorses a natural-rights doctrine similar to Locke’s. He wrote primarily for the French, addressing issues he thought decisive for them, especially reconciling the ultra-royalists and the French Catholic Church to the new democratic order. This guided the aspects of American democracy he wanted to emphasize. Thus Jesus Christ’s coming to earth was a political turning point in human history because he “made it understood that all members of the human species are naturally alike and equal.” Given aristocratic dominance in ancient society, without that event the principle of equality might never have been discovered.
Review Essay: Pius XII and the Battle for Rome
Authors: Greco Ernest A. ,   Society of Catholic Social Scientists
Published: August 2014

Robert Katz’s The Battle for Rome (2003) is an unfair indictment of Pope Pius XII. Through various distortions and oversights, Katz faults Pius’s “open city” strategy and his anti-communism for failing to protect the Jews and other Italians during the German occupation of Rome in World War II. In truth, the pope’s strategy was as successful as could reasonably be expected under the circumstances.
Ex Corde Ecclesiae, Social Science, and the Public Square
Authors: Simboli Brian ,   Society of Catholic Social Scientists
Published: August 2014

This essay explores the relationship between Ex Corde Ecclesiae and its application in the United States on the one hand and the practice and teaching of the social sciences on the other. The paper reflects on ways the bishops and laity can advance the social sciences, which provide the current-day lingua franca of public discourse, and expresses the need to invoke social scientific research in the public square.
Race to the Top, Value-Added Models, and the Catholic View of Education
Authors: Montes Guillermo ,   Society of Catholic Social Scientists
Published: August 2014

Race to the Top is resulting in the widespread adoption of value-added models to measure teacher performance. There are concerns about the reliability and validity of these methods and about the wisdom of the Federal government mandating how to conduct non-federal employees’ performance reviews. (Editor’s note: This article was written in June 2011.)
The Student Loan Crisis and the Future of Higher Education
Authors: Wenisch Michael ,   Society of Catholic Social Scientists
Published: August 2014

The crisis in student loans has grown to the point that outstanding student loan debt will likely exceed $1 trillion in early 2012. Yet employment prospects for college graduates have grown alarmingly bleak, particularly since 2008. The downturn in the world economy since 2008 is itself, in substantial measure, the outcome of the historic peaking of world oil production rates within the past six years. With the onset of permanent oil production rate declines within a few years’ time, the world economy faces an epoch of contraction destined to last decades. These broader economic developments are setting the stage for a tragic bursting of the bubble in student loan debt. The situation also raises acute moral questions revolving around a basic conflict between the interests of the institutional complex of higher education and the masses of students who financially sustain that complex.