bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biomaterial‐based notch signaling for the differentiation of hematopoietic stem cells into T cells
Authors: Taqvi Sabia , Dixit Lena , Roy Krishnendu 
Published: July 2006

AbstractThymocyte development takes place in a complex milieu of supportive cells and ECM that are responsible for the proliferation, adhesion, migration, and selection processes these cells undergo before reaching maturity. In recent years, the role of notch signaling in lymphocyte development, specifically T‐cell development, has been extensively characterized. Although notch ligand mediated signals have been shown to be a necessary component of T‐cell generation from stem cells, high‐throughput, synthetic biomaterial‐based systems for notch‐directed stem‐cell differentiation into lymphocytes are yet to be reported. Here, we present a microbead‐based, artificial notch signaling system to study stem‐cell differentiation into the T‐cell lineage. Magnetic microbeads were functionalized with the notch ligand DLL4 using streptavidin‐biotin binding and antibody–antigen coupling. Immunohistochemistry and flow cytometry analysis indicated ∼65% conjugation efficiency. Efficient notch signaling through these functionalized microbeads was demonstrated through a myotube inhibition assay in C2C12 myoblasts. Thy1.2+ early T cells were successfully generated from mouse bone marrow hematopoietic stem cells (BMHSCs) using DLL4 functionalized beads using both insert‐based and mixed stromal cell (OP9) coculture conditions, indicating that stem cell–stromal cell physical contact is not necessary for DLL4 directed T‐cell differentiation. Coculture studies with bead‐to‐cell ratios of 1:1 generated higher T‐cell differentiation efficiencies, compared to bead‐to‐cell ratios of 5:1. These data demonstrate the promising potential of this biomaterial‐based notch signaling system to generate T cells from stem cells and to elucidate the molecular interactions in T‐cell development. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Naked Sendai virus vector lacking all of the envelope‐related genes: reduced cytopathogenicity and immunogenicity
Authors: Yoshizaki Mariko , Hironaka Takashi , Iwasaki Hitoshi , Ban Hiroshi , Tokusumi Yumiko , Iida Akihiro , Nagai Yoshiyuki , Hasegawa Mamoru , Inoue Makoto 
Published: July 2006

AbstractBackgroundSendai virus (SeV) is a new class of cytoplasmic RNA vector that is free from genotoxicity that infects and multiplies in most mammalian cells, and directs high‐level transgene expression. We improved the vector by deleting all of the envelope‐related genes from the SeV genome and thus reducing its immunogenicity.MethodsThe matrix (M), fusion (F) and hemagglutinin‐neuraminidase (HN) genes‐deleted SeV vector (SeV/ΔMΔFΔHN) was recovered in a newly established packaging cell line. Then, the generated SeV/ΔMΔFΔHN vector was characterised by comparing with single gene‐deleted type SeV vectors.ResultsThis SeV/ΔMΔFΔHN vector carrying the green fluorescent protein gene in place of the envelope‐related genes could be propagated to a titer of more than 108 cell infectious units/ml. This vector showed an efficient transduction capability in vitro and in vivo, and the cytopathic effect and induction of neutralizing antibody in vivo were greatly reduced compared with those of single gene‐deleted type SeV vectors. No activity of neutralizing antibody or anti‐HN antibody was seen when SeV/ΔMΔFΔHN was transduced ex vivo. Additional introduction of amino acid mutations that had been identified from SeV strains causing persistent infections was also effective for the reduction of cytopathic effects.ConclusionsThe deletion of genes from the SeV genome and the additional mutation are very effective for reducing both the immunogenic and cytopathic reactions to the SeV vector. These modifications are expected to improve the safety and broaden the range of clinical applications of this new class of cytoplasmic RNA vector. Copyright © 2006 John Wiley & Sons, Ltd.
Degree of Branching of Highly Branched Polyurethanes Synthesized via the Oligomeric A2 Plus B3 Methodology
Authors: Fornof Ann R. , Glass Thomas E. , Long Timothy E. 
Published: July 2006

AbstractSummary: The oligomeric A2 plus monomeric B3 synthetic methodology provided highly branched, poly(ether urethane)s based on TMP (B3) and isocyanate endcapped polyethers. 13C NMR spectroscopic assignments for the branched polyurethanes were verified using model urethane‐containing compounds based on TMP and a monofunctional isocyanate (either cyclohexyl or phenyl isocyanate (PI)). Derivatization of hydroxyl endgroups with trifluoroacetic anhydride enhanced the 13C NMR resolution in spectra for branched polyurethanes. The 13C NMR resonance for the linear unit exhibited a broad shoulder due to quaternary carbons that were attributed to cyclic species in the highly branched polyurethanes. The classical DB calculation revealed the efficiency of the B3 monomer for branching; however, an equation that incorporated the linear contribution of the A2 oligomer provided a more accurate DB for highly branched polyurethanes.SEC chromatograms for increasing addition of A2.magnified imageSEC chromatograms for increasing addition of A2.
Poly(aspartic acid) Super‐Absorbent Resin Produced by Chemical Crosslinking and Physical Freeze/Thawing
Authors: Zhao Ying , Tan Tianwei 
Published: July 2006

AbstractSummary: Novel crosslinked poly(aspartic acid) super‐absorbent resins have been prepared using a chemical crosslinking agent and a freeze/thawing technique. This resin shows improved swelling behaviors as a result of the crystallization that serves as the physical crosslink. For further identification of microstructures and properties, SEM, DSC, X‐ray diffraction, and FT‐IR analyses have been used. To a certain extent, final structures and properties can be controlled by regulating the freeze/thawing conditions, including not only the number of freeze/thawing cycles, but also the temperature and time of both freezing and subsequent thawing. Its swelling behavior is significantly influenced by environmental conditions, such as ionic strength. Furthermore, the swelling ratio is also investigated in various physiological solutions.Swelling ratios of the novel PAsp super‐absorbers obtained with increasing number of freeze/thawing cycles.magnified imageSwelling ratios of the novel PAsp super‐absorbers obtained with increasing number of freeze/thawing cycles.
Glass Transition Temperature and Chain Flexibility of Ethylene‐Norbornene Copolymers from Molecular Dynamics Simulations
Authors: Carbone Paola , Rapallo Arnaldo , Ragazzi Massimo , Tritto Incoronata , Ferro Dino R. 
Published: July 2006

AbstractSummary: Model chains of ethylene‐norbornene copolymers were built up using the results of 13C NMR spectral analysis of copolymer samples synthesized with metallocene‐based catalysts. Our models statistically reproduce the microstructure, composition, and tacticity of the copolymer chains of experimental samples. They were used to test if MD simulations are suitable to investigate the relationships between microstructure and macroscopic properties. In particular, MD simulations were applied to calculate the glass transition temperature and to study the chain flexibility by the analysis of ACF of specific virtual bonds. Plots of specific volume versus temperature computed for models of four copolymer samples having different microstructures and norbornene contents yield Tg values in good agreement with experiments. Moreover, comparison of the ACFs provides some qualitative indications about the relationship between chain stereochemistry and Tg.ACF functions of the virtual bonds with microstructures NENE (bottom) and ENNE (top).magnified imageACF functions of the virtual bonds with microstructures NENE (bottom) and ENNE (top).
Capacity allocation with traditional and Internet channels
Authors: Dai Yue , Chao Xiuli , Fang Shu‐Cherng , Nuttle Henry L.W. 
Published: July 2006

AbstractIn this paper we study a capacity allocation problem for two firms, each of which has a local store and an online store. Customers may shift among the stores upon encountering a stockout. One question facing each firm is how to allocate its finite capacity (i.e., inventory) between its local and online stores. One firm's allocation affects the decision of the rival, thereby creating a strategic interaction. We consider two scenarios of a single‐product single‐period model and derive corresponding existence and stability conditions for a Nash equilibrium. We then conduct sensitivity analysis of the equilibrium solution with respect to price and cost parameters. We also prove the existence of a Nash equilibrium for a generalized model in which each firm has multiple local stores and a single online store. Finally, we extend the results to a multi‐period model in which each firm decides its total capacity and allocates this capacity between its local and online stores. A myopic solution is derived and shown to be a Nash equilibrium solution of a corresponding “sequential game.” © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006
A logistic regression/Markov chain model for NCAA basketball
Authors: Kvam Paul , Sokol Joel S. 
Published: July 2006

AbstractEach year, more than $3 billion is wagered on the NCAA Division 1 men's basketball tournament. Most of that money is wagered in pools where the object is to correctly predict winners of each game, with emphasis on the last four teams remaining (the Final Four). In this paper, we present a combined logistic regression/Markov chain model for predicting the outcome of NCAA tournament games given only basic input data. Over the past 6 years, our model has been significantly more successful than the other common methods such as tournament seedings, the AP and ESPN/USA Today polls, the RPI, and the Sagarin and Massey ratings. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006.
Optimal maintenance policies for serial, multi‐machine systems with non‐instantaneous repairs
Authors: Maillart Lisa M. , Fang Xiang 
Published: July 2006

AbstractWe study optimal age‐replacement policies for machines in series with non‐instantaneous repair times by formulating two nonlinear programs: one that minimizes total cost‐rate subject to a steady‐state throughput requirement and another that maximizes steady‐state throughput subject to a cost‐rate budget constraint. Under reasonable assumptions, the single‐machine cost‐optimal and throughput‐optimal solutions are unique and orderable, and the multi‐machine optimal solutions have appealing structure. Furthermore, we establish equivalence between the two formulations and provide an illustrative numerical example. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006
Effects of cueing in cooperative search
Authors: Jeffcoat David E. , Krokhmal Pavlo A. , Zhupanska Olesya I. 
Published: July 2006

AbstractWe consider the effects of cueing in a cooperative search mission that involves several autonomous agents. Two scenarios are discussed: one in which the search is conducted by a number of identical search‐and‐engage vehicles and one where these vehicles are assisted by a search‐only (reconnaissance) asset. The cooperation between the autonomous agents is facilitated via cueing, i.e., the information transmitted to the agents by a searcher that has just detected a target. The effect of cueing on the target detection probability is derived from first principles using a Markov chain analysis. In particular, it is demonstrated that the benefit of cueing on the system's effectiveness is bounded. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006
Inventory control and periodic price discounting campaigns
Authors: Chaouch Ben A. 
Published: July 2006

AbstractThis paper develops an inventory model that determines replenishment strategies for buyers facing situations in which sellers offer price‐discounting campaigns at random times as a way to drive sales or clear excess inventory. Specifically, the model deals with the inventory of a single item that is maintained to meet a constant demand over time. The item can be purchased at two different prices denoted high and low. We assume that the low price goes into effect at random points in time following an exponential distribution and lasts for a random length of time following another exponential distribution. We highlight a replenishment strategy that will lead to the lowest inventory holding and ordering costs possible. This strategy is to replenish inventory only when current levels are below a certain threshold when the low price is offered and the replenishment is to a higher order‐up‐to level than the one currently in use when inventory depletes to zero and the price is high. Our analysis provides new insight into the behavior of the optimal replenishment strategy in response to changes in the ratio of purchase prices together with changes in the ratio of the duration of a low‐price period to that of a high‐price period. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007.
Variational solution of fractional advection dispersion equations on bounded domains in ℝd
Authors: Ervin Vincent J. , Roop John Paul 
Published: July 2006

AbstractIn this article, we discuss the steady state fractional advection dispersion equation (FADE) on bounded domains in ℝd. Fractional differential and integral operators are defined and analyzed. Appropriate fractional derivative spaces are defined and shown to be equivalent to the fractional dimensional Sobolev spaces. A theoretical framework for the variational solution of the steady state FADE is presented. Existence and uniqueness results are proven, and error estimates obtained for the finite element approximation. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 23: 256–281, 2007
Construction of nonstandard finite difference schemes for $1{1\over 2}$ space‐dimension‐coupled PDEs
Authors: Mickens Ronald E. , Jordan P.M. 
Published: July 2006

AbstractTwo coupled PDEs, where one has a diffusion term and the other does not, are defined to be
$1{1\over 2}$
space‐dimension systems. We show how to construct nonstandard finite difference schemes for such systems and demonstrate that they are positivity‐preserving. These methods also allow the calculation of an explicit functional relationships between the time and space step‐sizes. The case of water flowing through fractured bedrock is used to illustrate our procedure. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007
Superconvergence of finite volume element method for a nonlinear elliptic problem
Authors: Bi Chunjia 
Published: July 2006

AbstractIn this article, we consider the finite volume element method for the second‐order nonlinear elliptic problem and obtain the H1 and W1,∞ superconvergence estimates between the solution of the finite volume element method and that of the finite element method, which reveal that the finite volume element method is in close relationship with the finite element method. With these superconvergence estimates, we establish the Lp and W1,p (2 < p ≤ ∞) error estimates for the finite volume element method for the second‐order nonlinear elliptic problem. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007
A note on adaptive approximation in Sobolev spaces
Authors: Liu Song‐Tao 
Published: July 2006

AbstractIn this article, we consider the adaptive approximation in Sobolev spaces. After establishing some norm equivalences and inequalities in Besov spaces, we are able to prove that the best N terms approximation with wavelet‐like basis in Sobolev spaces exhibits the proper approximation order in terms of N−1. This indicates that the computational load in adaptive approximation is proportional to the approximation accuracy. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007
Numerical solution of the one‐dimensional wave equation with an integral condition
Authors: Saadatmandi Abbas , Dehghan Mehdi 
Published: July 2006

AbstractThe hyperbolic partial differential equation with an integral condition arises in many physical phenomena. In this research a numerical technique is developed for the one‐dimensional hyperbolic equation that combine classical and integral boundary conditions. The proposed method is based on shifted Legendre tau technique. Illustrative examples are included to demonstrate the validity and applicability of the presented technique. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 23: 282–292, 2007
New kinds of solitons and periodic solutions to the generalized KdV equation
Authors: Wazwaz Abdul‐Majid 
Published: July 2006

AbstractIn this work, the sine‐cosine method, the tanh method, and specific schemes that involve hyperbolic functions are used to study solitons and periodic solutions governed by the generalized KdV equation. New solutions are determined by using the hyperbolic functions schemes. The study introduces new approaches to handle nonlinear PDEs in the solitary wave theory. © 2006 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 23: 247–255, 2007
In vitro evaluation of cellulose acetate hemodialyzer immobilized with heparin
Authors: Kung Fu‐Chen , Chou Wen‐Li , Yang Ming‐Chien 
Published: July 2006

AbstractIn this study, heparin was immobilized onto cellulose acetate hollow fibers to improve the anticoagulation performance during hemodialysis. In vitro evaluation was carried out using mini‐hemodialyzer circulating with fresh porcine whole blood to simulate kidney therapy. The dialysis performance and hemocompatibility were estimated. The results showed that heparinized hemodialyzer could be used through out the whole dialysis time (4 hr) without injecting additional heparin to prevent coagulation in the dialysis system. In addition, the hemocompatibility was evaluated by measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and fibrinogen time (FT). The complete blood count (CBC) including red blood cell (RBC), hemoglobin (Hgb), hematocrit (Hct), white blood cell (WBC), and platelet were determined. The results showed that heparinization could keep the CBC stable during dialysis, whereas unmodified cellulose acetate hemodialyzer would cause a decrease in RBC unless heparin was injected during dialysis. Heparinized hemodialyzer showed longer APTT, PT, and FT than unmodified hemodialyzer. Heparinized hemodialyzer also showed slightly higher clearance than unmodified hemodialyzer. These results indicated that the dialysis performance and hemocompatibility of cellulose acetate hemodialyzer could be improved by the immobilization of heparin. Copyright © 2006 John Wiley & Sons, Ltd.
PIN1 expression contributes to hepatic carcinogenesis
Authors: Pang RW , Lee TK , Man K , Poon RT , Fan S‐T , Kwong Y‐L , Tse E 
Published: July 2006

AbstractThe phospho‐Ser/Thr‐Pro specific prolyl‐isomerase PIN1 is over‐expressed in more than 50% of hepatocellular carcinomas (HCCs). To investigate its potential oncogenicity, we over‐expressed PIN1 in a non‐transformed human liver cell line MIHA. This resulted in up‐regulation of β‐catenin and cyclin D1, leading to anchorage‐independent growth in soft agar and tumorigenicity in nude mice. To further validate the role of PIN1 in hepatocarcinogenesis, PIN was suppressed by RNA interference (siRNA) in the HCC cell line PLC/PRF/5. siRNA‐PIN1 transfection of PLC/PRF/5 cells led to repression of PIN1 expression, resulting in decreased levels of β‐catenin and cyclin D1. siRNA‐PIN1 transfectants showed lower cell proliferation rates, reduced colony formation, and retarded cell cycle progression, with an increase in cells residing in G0/G1. Furthermore, soft agar colony formation was depressed, and tumorigenicity in nude mice was abrogated. These findings implicate PIN1 expression as an important step in hepatic carcinogenesis. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Expression of the TAL1/SCL transcription factor in physiological and pathological vascular processes
Authors: Tang T , Shi Y , Opalenik S R , Brantley‐Sieders D M , Chen J , Davidson J M , Brandt S J 
Published: July 2006

AbstractThe TAL1/SCL transcription factor is essential for haematopoietic commitment and vascular remodelling during embryonic development. To help clarify its role in postnatal vascular processes, we characterized the expression of mouse Tal1 protein by immunocytochemistry in several experimental models of blood vessel formation. In adult mice, Tal1 protein was expressed in rare microvascular endothelial cells and in extravascular cells provisionally identified as endothelial progenitors from their morphology, proximity to vessels and expression of vascular endothelial growth factor receptor‐2. The number of Tal1‐expressing endothelial cells increased significantly but transiently in all the models—hormone‐induced ovulation, wound healing and tumour development. Finally, Tal1 protein was detected in the nuclei of newly formed lymphatic endothelial cells in tumour‐bearing animals. These results show that TAL1 is expressed by vascular endothelial cells and endothelial progenitors at sites of physiological and pathological neovascularization and suggest a role for this transcription factor in adult vasculogenesis. This work also provides the first evidence for TAL1 expression in lymphangiogenesis. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Epididymal cystadenomas and epithelial tumourlets: effects of VHL deficiency on the human epididymis
Authors: Gläsker S , Tran MGB , Shively SB , Ikejiri B , Lonser RR , Maxwell PH , Zhuang Z , Oldfield EH , Vortmeyer AO 
Published: July 2006

AbstractAlthough epididymal cystadenomas (ECAs) are among the most frequent VHL disease‐associated tumours, fundamental questions about their pathogenesis have remained unanswered. Classification of ECAs is controversial, and the cell of origin is unknown. It is also unknown whether ECAs—like other VHL disease‐associated tumours—arise as a result of VHL gene inactivation, and whether ECAs exhibit subsequent activation of hypoxia‐inducible factor HIF. Moreover, the morphological spectrum of earliest ECA formation is unknown. In a detailed molecular pathological analysis of a series of epididymides collected from VHL patients at autopsy, we found that ECAs are true neoplasms that arise secondary to inactivation of the wild‐type copy of the VHL gene, followed by early and simultaneous activation of HIF1 and HIF2 associated with up‐regulation of downstream targets, including CAIX and GLUT‐1. The observations also indicate that ECA formation evolves from a variety of microscopic epithelial tumourlets, and that these tumourlets are confined to the efferent ductular system. Although genetic and immunohistochemical analysis of precursor structures consistently revealed VHL gene inactivation and activation of HIF in the precursor lesions, only a small subset appears to progress into frank cystadenoma. Thus, ECA tumorigenesis in VHL disease shares fundamental principles with tumorigenesis in other affected organ systems. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.