bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dry film method with ytterbium as the internal standard for near infrared spectroscopic plasma glucose assay coupled with boosting support vector regression
Authors: Zhou Yan‐Ping , Jiang Jian‐Hui , Wu Hai‐Long , Shen Guo‐Li , Yu Ru‐Qin , Ozaki Yukihiro 
Published: December 2006

AbstractA novel near infrared (NIR) spectroscopic measurement technique, dry film method, has been proposed for the determination of glucose in plasma. Rare earth element ytterbium (Yb) has been taken in the dry film method as the internal standard to compensate for the thickness variation of the dry films. This technique circumvents the interference from water absorption and requires only 50 µl of sample. Support vector regression (SVR) as a multivariate calibration method has been combined with boosting for the development of a boosting support vector regression (BSVR) method for the dry film measurement modeling. The introduction of boosting drastically enhances the performance of individual SVR model. The results show that the glucose in plasma can be determined over the 0.4–20 mmol/L concentration range with satisfactory accuracy using the dry film technique coupled with the BSVR method. Moreover, the performance of BSVR was compared favorably with that of the conventional SVR and PLS. Copyright © 2006 John Wiley & Sons, Ltd.
Reengineering for Parallelism: an entry point into PLPP for legacy applications
Authors: Massingill Berna L. , Mattson Timothy G. , Sanders Beverly A. 
Published: December 2006

AbstractMany parallel programs begin as legacy sequential code that is later reengineered to take advantage of parallel hardware. This paper presents a pattern called Reengineering for Parallelism to help with this task. The new pattern is intended to be used in conjunction with PLPP (Pattern Language for Parallel Programming), described in our book (Mattson TG, Sanders BA, Massingill BL. Patterns for Parallel Programming. Addison‐Wesley: Reading, MA, 2004). PLPP contains a structured collection of patterns and embodies a methodology for developing parallel programs in which the programmer starts with a good understanding of the problem, works through a sequence of patterns, and finally ends up with the code. Most of the patterns in PLPP are also applicable when reengineering legacy code, but it is not always clear how to get started. Reengineering for Parallelism provides an alternate point of entry into PLPP and addresses particular issues that arise when dealing with legacy code. Copyright © 2006 John Wiley & Sons, Ltd.
Stabilizing large‐scale generalized systems on parallel computers using multithreading and message‐passing
Authors: Benner Peter , Castillo Maribel , Mayo Rafael , Quintana‐Ortí Enrique S. , Quintana‐Ortí Gregorio 
Published: December 2006

AbstractWe discuss the parallelization of an efficient algorithm for the partial stabilization of large‐scale linear control systems in generalized state‐space form. The algorithm is composed of highly parallel iterative schemes that appear in the computation of certain matrix functions. Here we evaluate different approaches to exploit parallelism at two levels, based on threads and processes. Our experimental results on a cluster of symmetric multiprocessors and a CC‐NUMA platform show that the efficiency of the matrix operations underlying the iterative schemes carry over to the parallel implementation of the stabilization algorithm. Copyright © 2006 John Wiley & Sons, Ltd.
The Properties of Si1–xGex Nanodot Arrays Prepared by Plasma‐Enhanced CVD on Porous Alumina Templates
Authors: Hu H. , He D. 
Published: December 2006

AbstractSi1–xGex films with nanodot arrays are prepared on anodic aluminum oxide (AAO) templates by plasma‐enhanced (PE)CVD. The structure and morphology of the films are investigated using X‐ray diffraction (XRD) spectroscopy and transmission electron microscopy (TEM). It is found that the size of the Si1–xGex grains is controlled by the pore diameter of the alumina substrate, which can be modulated during the preparation process. Intense visible photoluminescence (PL) is observed from the samples, and a remarkable red‐shift of the luminescence peak position is shown with increase in the content of Ge. Conductivity measurements show that electron tunneling is enhanced with increase of the strains stored in the sample.
Effects of Synthesis Conditions on Self‐Organized Growth of Aligned Arrays of Silicon Nanowires
Authors: Niu J.‐J. , Wang J.‐N. 
Published: December 2006

The effects of CVD synthesis conditions, including nanochannel alumina (NCA) properties, catalyst distribution, and growth parameters on aligned arrays of silicon nanowires (SiNWs) are investigated. Array‐ordered SiNWs are achieved by optimizing the above factors according to the vapor–liquid–solid (VLS) and nanochannel physical limitation mechanism. The study of arrays of SiNWs will permit better understanding of the growth mechanism and develop potential applications in nanoelectronics technology.
Plasma Characterization of Oxygen‐Tetramethylsilane Mixtures for the Plasma‐Enhanced CVD of SiOxCyHz Thin Films
Authors: Yanguas‐Gil Á. , Barranco Á. , Cotrino J. , Gröning P. , González‐Elipe A. R. 
Published: December 2006

AbstractThe plasma‐enhanced (PE)CVD of SiOxCyHz thin films from O2/Ar/tetramethylsilane (TMS) mixtures, in a low‐pressure microwave electron cyclotron resonant (ECR) plasma reactor, has been studied. The discharge has been analyzed by mass spectrometry (MS) and optical emission spectroscopy (OES) for varying amounts of oxygen in the gas mixture both in the presence and in the absence of argon. The films obtained have been characterized by Fourier transform infrared (FTIR) and X‐ray photoelectron spectroscopy (XPS). It is found that the electron impact of the TMS molecules and their dissociative ionization play an important role in the deposition process. Si(OH)x(CH3)3–x species, produced by reactions between the Si(CH3)4 molecule and Si(CH3)3+ ion fragments with O and O2, have been identified as important reaction intermediates. Such species form in different proportions depending on the O2/TMS ratio in the gas mixture. It is proposed that their incorporation onto the surface of the growing films accounts for the wide range of compositions achieved (ranging from SiO2 to almost Si:C:H) and the high concentration of Si‐C bonds experimentally detected in the SiOxCyHz thin films.
Neural bandwidth allocation function (NBAF) control scheme at WiMAX MAC layer interface
Authors: Marchese Mario , Mongelli Maurizio 
Published: December 2006

AbstractThe paper proposes a bandwidth allocation scheme to be applied at the interface between upper layers (IP, in this paper) andMedium Access Control(MAC) layer over IEEE 802.16 protocol stack. The aim is to optimally tune the resource allocation to match objective QoS (Quality of Service) requirements. Traffic flows characterized by different performance requirements at the IP layer are conveyed to the IEEE 802.16 MAC layer. This process leads to the need for providing the necessary bandwidth at the MAC layer so that the traffic flow can receive the requested QoS.The proposed control algorithm is based on real measures processed by a neural network and it is studied within the framework of optimal bandwidth allocation andCall Admission Controlin the presence of statistically heterogeneous flows. Specific implementation details are provided to match the application of the control algorithm by using the existing features of 802.16 request–grant protocol acting at MAC layer. The performance evaluation reported in the paper shows the quick reaction of the bandwidth allocation scheme to traffic variations and the advantage provided in the number of accepted calls. Copyright © 2006 John Wiley & Sons, Ltd.
Phospholipase Cγ negatively regulates Rac/Cdc42 activation in antigen‐stimulated mast cells
Authors: El‐Sibai Mirvat , Backer Jonathan M. 
Published: December 2006

AbstractThe Rho GTPases Rac and Cdc42 play a central role in the regulation of secretory and cytoskeletal responses in antigen‐stimulated mast cells. In this study, we examine the kinetics and mechanism of Rac and Cdc42 activation in the rat basophilic leukemia RBL‐2H3 cells. The activation kinetics of both Rac and Cdc42 show a biphasic profile, consisting of an early transient peak at 1 min and a late sustained activation phase at 20–40 min. The inhibition of phospholipase C (PLC)γ causes a twofold increase in Rac and Cdc42 activation that coincides with a dramatic production of atypical filopodia‐like structures. Inhibition of protein kinase C using bisindolylmaleimide mimics the effect of PLCγ inhibition on Rac activation, but not on Cdc42 activation. In contrast, depletion of intracellular calcium leads to a complete inhibition of the early activation peak of both Rac and Cdc42, without significant effects on the late sustained activation. These data suggest that PLCγ is involved in a negative feedback loop that leads to the inhibition of Rac and Cdc42. They also suggest that the presence of intracellular calcium is a prerequisite for both Rac and Cdc42 activation.
CD4+CD25high regulatory T cells reduce T cell transendothelial migration in cancer patients
Authors: Enarsson Karin , Lundin B. Samuel , Johnsson Erik , Brezicka Thomas , Quiding‐Järbrink Marianne 
Published: December 2006

AbstractCell‐mediated immunity is thought to be the main mechanism of anti‐tumour responses of the host, but it is not known if cancer disease affects T cell recruitment from blood to tissues. Therefore, we compared Heliobacter pylori‐induced T cell transendothelial migration (TEM) in H. pylori‐infected gastric carcinoma patients, colon and lung carcinoma patients and healthy volunteers. H. pylori induced significant T cell migration from all groups. However, there was a dramatic reduction of T cell TEM in gastric carcinoma patients (80%) compared to healthy individuals. A similarly reduced transmigration was also seen in colon and lung carcinoma patients. We found significantly increased frequencies of Treg cells in the blood of gastric carcinoma patients compared to healthy individuals, and depletion of Treg cells from the blood of these patients prior to TEM restored T cell migration. The effect of Treg cells was largely dependent on cell‐cell contact, but not on IL‐10 or TGF‐β. In addition, the presence of Treg cells led to reduced T cell attachment to endothelium and decreased production of T cell‐recruiting chemokines during TEM. In conclusion, Treg cell‐mediated reduction of T cell TEM may reduce T cell recruitment in patients with epithelial malignancies, thereby hampering anti‐tumour responses.
Regulation of intestinal immunity: Effects of the oral adjuvant Escherichia coli heat‐labile enterotoxin on migrating dendritic cells
Authors: Milling Simon W. F. , Yrlid Ulf , Jenkins Chris , Richards Claire M. , Williams Neil A. , MacPherson Gordon 
Published: December 2006

AbstractEscherichia coli heat‐labile enterotoxin (Etx) is an oral adjuvant in mice. We show that this is also true for rats. To understand this adjuvant activity we examined lymph dendritic cells (DC) migrating from the intestine to mesenteric lymph nodes (MLN) in animals fed Etx. These DC can prime antigen‐specific antibody responses. We show that in rats the small intestine contains 7–24 million DC and 8 × 105 of these migrate to MLN each day. Surprisingly, Etx does not stimulate increased migration of lymph DC. However, oral Etx affects the activation, antigen transport and localization of migratory DC. Specifically, expression of CD25 increases on the CD172ahigh subset of lymph DC. Oral Etx also increases the number of CD172ahigh lymph DC containing co‐administered ovalbumin. CD172ahigh lymph DC treated with Etx in vitro, or purified from the lymph of animals fed Etx, stimulate stronger proliferative responses from primed T cells. Etx also directs more of the CD172ahigh lymph DC into the central region of the MLN T cell areas. This change in DC localization is associated with an increase in the expression of CCR7. These data help advance our understanding of the role of DC in initiating mucosal immune responses in vivo.
CD8+ suppressor‐mediated regulation of human CD4+ T cell responses to glutamic acid decarboxylase 65
Authors: James Eddie A. , Kwok William W. 
Published: December 2006

AbstractAlthough potentially autoreactive T cells are present even in healthy subjects, most individuals do not develop autoimmune disease. It has been well demonstrated that CD4+CD25+ regulatory T cells play a significant role in controlling the expansion of autoreactive T cells in the periphery. However, some healthy individuals exhibit measurable responses to self peptide even in the presence of CD4+CD25+ regulatory cells. This article describes the regulation of human CD4+ T cell responses to glutamic acid decarboxylase 65 (GAD65), an autoantigen implicated in type‐1 diabetes, by autologous CD8+ suppressor T cells. In cells cultured from healthy individuals, the inclusion of autologous CD8+ T cells at physiological levels resulted in a dramatic decrease in the magnitude of in vitro CD4+ T cell responses to GAD65 peptide. Based on transwell experiments, the observed suppression was cell contact‐dependent. However, antibody blocking studies indicated that suppression was mediated by IL‐10. Cell fractionation studies suggested that CD8+ suppressor T cells originate from the CD45RA+CD27– population. The suppression of CD4+ T cell responses to GAD65 in healthy individuals raises the possibility that CD8+ suppressor T cells play an important role in controlling potentially autoreactive T cells in the general population.
IL‐10 inhibits endothelium‐dependent T cell costimulation by up‐regulation of ILT3/4 in human vascular endothelial cells
Authors: Gleissner Christian A. , Zastrow Arne , Klingenberg Roland , Kluger Martin S. , Konstandin Mathias , Celik Sultan , Haemmerling Susanne , Shankar Vijay , Giese Thomas , Katus Hugo A. , Dengler Thomas J. 
Published: December 2006

AbstractEffects of IL‐10 on endothelium‐dependent T cell activation have not been investigated in detail. We confirm expression of the IL‐10 receptor and effective signaling via STAT‐3 in human umbilical vein endothelial cells (HUVEC). In CD4 T cell cocultures with HUVEC, pretreatment of endothelial cells with IL‐10 resulted in significant dose‐dependent inhibition of CD4 T cell proliferation, which also occurred when IL‐10 was removed after pretreatment before starting cocultures. Th1/Th2 polarization of proliferated T cells, endothelial nitric oxide (NO), or IL‐12 production were unchanged. However, IL‐10 stimulation resulted in up‐regulation of SOCS‐3, a negative regulator of cytokine secretion, and induction of the inhibitory surface molecules immunoglobulin‐like transcript 3 and 4 (ILT3/ILT4) in EC, potentially involving glucocorticoid‐induced leucine zipper (GILZ). Addition of blocking antibodies against ILT3/ILT4 to EC/T cell cocultures resulted in nearly complete reestablishment of T cell proliferation. In contrast, addition of soluble ILT3 or overexpression of ILT3 in cocultures significantly reduced T cell proliferation. No induction of foxp3+ regulatory T cells was seen. In conclusion, the T cell costimulatory potential of human EC is markedly suppressed by IL‐10 due to up‐regulation of ILT3/ILT4, obviously not involving generation of Treg. This identifies a novel action of IL‐10 in EC and a potential therapeutical target for local immunomodulation.
Stimuli that enhance IgA class switching increase histone 3 acetylation at Sα, but poorly stimulate sequential switching from IgG2b
Authors: Kaminski Denise A. , Stavnezer Janet 
Published: December 2006

AbstractGerm‐line (GL) α transcription can be induced in mouse splenic B cells by LPS and TGF‐β. This stimulation results in ∼1% IgA+ cells, which can be increased by IL‐4, IL‐5, and anti‐IgD dextran (αδDex). To determine the mechanism of this increase, we asked whether IgA class switching correlates with acetylation of histone 3 at Sα, the switch region for IgA. In the presence of the survival factor B lymphocyte stimulator (BLyS), acetylated histone 3 (AcH3) at Sα was changed little by TGF‐β in LPS‐stimulated mouse splenic B cell cultures, despite induction of GLα RNA. Compared with BLyS/LPS/TGF‐β alone, treatment with BLyS/LPS/TGF‐β/IL‐4/IL‐5/αδDex increased AcH3 at Sα fourfold, and also increased GLα RNA levels more than eightfold. By contrast, IgG2b class switching was optimal in BLyS/LPS/TGF‐β alone, and was suppressed by IL‐4/IL‐5/αδDex. Thus, B cell activators that increase IgA class switching do not increase IgG2b class switching. Further investigation showed that in contrast to purified IgM+ cells, IgG2b+ cells switched poorly to IgA in response to BLyS/LPS/TGF‐β/IL‐4/IL‐5/ ± αδDex. These results suggest that IgA class switching is unusual among isotypes in its requirement for multiple B cell activation signals in addition to LPS and the cytokine that initiates the corresponding GL transcription.
Dinuclear Metallocenes with a Modulated Biphenylene Bridge for Olefin Polymerization
Authors: Kim Seong Kyun , Kim Hwa Kyu , Lee Min Hyung , Yoon Seung Woong , Han Yonggyu , Park Sungjin , Lee Junseong , Do Youngkyu 
Published: December 2006

AbstractDinuclear group 4 metallocene catalysts linked by a biphenylene or 1,2‐diphenylethylene bridge, namely [4,4′‐(C5Me4)2(C6H4)2][CpZrCl2]2 (2a), [p‐(C5Me4)C6H4CH2]2[CpZrCl2]2 (2b), [p‐(3,4‐Me2C5H2)C6H4CH2]2[CpZrCl2]2 (2c), [(C5Me4)2(C6H4)2][TiCl3]2 (3a), [p‐(C5Me4)C6H4CH2]2[TiCl3]2 (3b), and [p‐(3,4‐Me2C5H2)C6H4CH2]2[TiCl3]2 (3c), have been prepared and the crystal structures of 2b and 3b determined by X‐ray diffraction methods. The crystal structures reveal that these complexes consist of two equivalent metal units inverted with respect to the center of the bridge. All the complexes were tested for the polymerization of ethylene and styrene in the presence of methylaluminoxane (MAO), and direct comparisons of their catalytic properties with those of the corresponding mononuclear analogues [(PhC5Me4)CpZrCl2] (4a), [(p‐TolC5Me4)CpZrCl2] (4b), [(1‐p‐Tol‐3,4‐Me2C5H2)CpZrCl2] (4c), [(PhC5Me4)TiCl3] (5a), [(p‐TolC5Me4)TiCl3] (5b), and [(1‐p‐Tol‐3,4‐Me2C5H2)TiCl3] (5c) were performed. The dinuclear zirconocenes show a high activity in ethylene polymerization comparable with those of the corresponding mononuclear catalysts and give an increased molecular weight of polyethylene. The dinuclear half‐sandwich titanocenes exhibit similar or slightly lower activity and molecular weight in styrene polymerization compared with their mononuclear analogues. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Blue‐Light‐Emitting Complexes: Cationic (2‐Phenylpyridinato)iridium(III) Complexes with Strong‐Field Ancillary Ligands
Authors: Shik Chin Chong , Eum Min‐Sik , yi Kim Song , Kim Choongil , Kwon Kang Sung 
Published: December 2006

AbstractThe emission λmax are strikingly shorter (451, 482 nm) for the cationic dicarbonyl complex [Ir(ppy)2(CO)2]+ (2a) than those (473, 495 nm) of the anionic dicyano complex [Ir(ppy)2(CN)2]–, where CO and CN– are both sp carbon coordinating ligands and known to be strong‐field ligands showing a high trans effect. Sky‐blue‐light emission (λmax = 441–443 and 470–471 nm) could be obtained by modifying the ppy ligand to F2Meppy (2,4‐difluoro‐2‐phenyl‐m‐methylpyridinato anion) to prepare [Ir(F2Meppy)2LL′]+ [LL′ = (CO)2 (2aF2Me), (PPh2Me)2 (2bF2Me)]. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis of the η2‐1‐Phosphaallene Complexes [(η5‐C5H5)(CO)(NO)W{η2‐R1P=C=C(R2)H}] (R1 = tBu, Cy; R2 = Ph, H) from [(η5‐C5H5)(CO)(NO)W=C=C(R2)H] (R2 = Ph, H) and Inversely Polarized Phosphaalkenes R1P=C(NMe2)2 (R1 = tBu, Cy), and Their Structure
Authors: Weber Lothar , Noveski Gabriel , Braun Thomas , Stammler Hans‐Georg , Neumann Beate 
Published: December 2006

AbstractThe reaction of the vinylidene complex [(η5‐C5H5)(CO)(NO)W=C=C(H)Ph] (9) with the phosphaalkenes RP=C(NMe2)2 (1a: R = tBu; 1c: R = c‐C6H11) affords the novel η2‐1‐phosphaallene complexes [η2‐{RP=C=C(H)Ph}W(CO)(NO)(η5‐C5H5)] (14: R = tBu; 15: R = c‐C6H11) in addition to the carbene complex [(η5‐C5H5)(CO)(NO)W=C(NMe2)C(Ph)=C(H)NMe2] (16). Similarly, treatment of [(η5‐C5H5)(CO)(NO)W=C=CH2] (12) with the phosphaalkenes gives rise to the formation of [η2‐{RP=C=CH2}W(CO)(NO)(η5‐C5H5)] (17: R = tBu; 18: R = c‐C6H11). The novel compounds 14, 15, 17, and 18 were characterized by elemental analysis and by spectroscopy (IR, 1H, 13C NMR, MS). Moreover, the molecular structures of 14 and 16 were determined by X‐ray diffraction analyses. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Ex‐Chiral‐Pool Synthesis of β‐Hydroxyphosphonate Nucleoside Analogues
Authors: Gallier Franck , Peyrottes Suzanne , Périgaud Christian 
Published: December 2006

AbstractA new series of mononucleotide analogues bearing a nonhydrolysable P–C bond instead of the P–O phosphate linkage is presented. We intend to set up an approach that allows the synthesis of β‐hydroxyphosphonate nucleoside analogues as a single diastereoisomer. In this respect, the key “sugar‐phosphonate” intermediate was obtained through an Arbusov reaction from an iodosugar derivative in which the stereochemistry of the β‐hydroxy group is determined by the choice of the starting material and remains in the resulting nucleotide analogues. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Concave Pyridines for Bifunctional Acid–Base Catalysis
Authors: Liebig Timo , Abbass Michael , Lüning Ulrich 
Published: December 2006

AbstractTwo bifunctional concave acid–base catalysts, 1 and 2, have been synthesized starting from 2,6‐dibromopyridine (9) and 2,6‐bis(ω‐alkenyloxy)phenylboronic acids 8 and 10 which end up as bridgeheads in final bimacrocycles 1 and 2. One bridgehead contained an additional substituent in the 4‐position. The respective protected 4‐hydroxymethyl‐substituted phenylboronic acids 8 were synthesized from 4‐bromo‐3,5‐dihydroxybenzoic acid (3) in five steps. 4‐Unsubstituted boronic acid 10 and 4‐substituted boronic acid 8 were then attached to 9 by subsequent Suzuki couplings to give tetra‐ω‐alkenes 12. By ring‐closing metathesis of 12, bimacrocyclic dienes 13 and 17 were formed. After deprotection of the 4‐hydroxymethyl group of one bridgehead, a 3‐hydroxybenzoate was coupled to 14 to give ester 15 which gave bifunctional acid–base catalyst 1 upon hydrolysis. Analogously, homologue 2 was synthesized, but before coupling the bimacrocycle to the benzoate, tetraene 14 was hydrogenated to 18. Acidic and basic centers in 1 (49 % from 9) and 2 (19 % from 9) are at least 5 Å apart.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Concave Imidazolinium Salts as Precursors to Concave N‐Heterocyclic Carbenes
Authors: Winkelmann Ole , Näther Christian , Lüning Ulrich 
Published: December 2006

AbstractConcave bimacrocyclic imidazolinium ions 8 have been synthesized as precursors for N‐heterocyclic carbenes 9 (NHC) in 13 to 29 % overall yields based on 2‐nitroresorcinol (1). As bridgeheads, 2,6‐bis(ω‐alkenyloxy)anilines 3 have been synthesized from 1. Reaction of 3 with oxalyl chloride, reduction to respective diamines 5, and ring closure with triethyl orthoformate gave N,N‐diaryl‐substituted imidazolinium ions 6. The terminal vinyl groups were connected by ring‐closing metathesis to give bimacrocyclic imidazolinium ions 7, whose alkene functions were hydrogenated to give saturated bimacrocyles 8. The structure of 8a was elucidated by X‐ray analysis. The respective NHC 9 was generated by deprotonation with potassium tert‐butoxide, and 9 was scavenged with CS2 to give adduct 10. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)