bluuebunny/crossref_metadata_2025 huggingface dataset:
CXC Chemokine Ligand 2 Induced by Receptor Activator of NF-κB Ligand Enhances Osteoclastogenesis
Authors: Ha Jeongim , Choi Hyo-Sun , Lee Youngkyun , Kwon Hyung-Joo , Song Yeong Wook , Kim Hong-Hee
Published: April 2010

CXCL2 has been known to regulate immune functions mainly by chemo-attracting neutrophils. In this study, we show that CXCL2 can be induced by receptor activator of NF-κB ligand, the osteoclast (OC) differentiation factor, through JNK and NF-κB signaling pathways in OC precursor cells. CXCL2 in turn enhanced the proliferation of OC precursor cells of bone marrow-derived macrophages (BMMs) through the activation of ERK. Knockdown of CXCL2 inhibited both the proliferation of and the ERK activation in BMMs. During osteoclastogenesis CXCL2 stimulated the adhesion and the migration of BMMs. Moreover, the formation of OCs from BMMs was significantly increased on treatment with CXCL2. Conversely, the CXCL2 antagonist repertaxin and a CXCL2 neutralizing Ab potently reduced receptor activator of NF-κB ligand-induced osteoclastogenesis. Furthermore, CXCL2 evoked fulminant bone erosion in the in vivo mouse experiments. Finally, prominent upregulation of CXCL2 was detected in synovial fluids and sera from rheumatoid arthritis patients, suggesting a potential involvement of CXCL2-mediated osteoclastogenesis in rheumatoid arthritis-associated bone destruction. Thus, CXCL2 is a novel therapeutic target for inflammatory bone destructive diseases.
Disordered Lymphoid Purine Metabolism Contributes to the Pathogenesis of PersistentBorrelia gariniiInfection in Mice
Authors: Yegutkin Gennady G. , Hytönen Jukka , Samburski Sergei S. , Yrjänäinen Heta , Jalkanen Sirpa , Viljanen Matti K.
Published: April 2010

Extracellular ATP and adenosine are important regulators of immune responses; however, contribution of purinergic signaling to host defense during persistent microbial infections remains obscure. Lyme borreliosis is a common arthropod-borne infection caused by Borrelia burgdorferi sensu lato. In this study, we investigated whether lymphoid purinergic signaling contributes to the mechanisms by which borreliae species evade the immune system and trigger joint inflammation. Intracutaneous inoculation of Borrelia garinii to C3H/He mice induced symptomatic infection manifested in elevated levels of borrelia-specific IgG Abs, persistent spirochete dissemination into the tissues and joint swelling, as well as ∼2- to 2.5-fold enlargement of draining lymph nodes with hyperplasia of B cell follicle area and L-selectin shedding from activated T lymphocytes. Purine catabolism was also activated in lymph nodes but not spleen and blood of infected C3H/He mice within the first 4 postinfection weeks, particularly manifested in transient upregulations of adenosine triphosphatase/ectonucleoside triphosphate diphosphohydrolase and ecto-5′-nucleotidase/CD73 on CD4+CD8+ T lymphocytes and adenosine deaminase activity on B220+ B lymphocytes. Compared with borrelia-susceptible C3H/He strain, lymphocytes from C57BL/6 mice displayed markedly enhanced adenosine-generating capability due to approximately three times higher ratio of ecto-5′-nucleotidase to adenosine deaminase. Borrelia-infected C57BL/6 mice efficiently eradicated the inoculated spirochetes at more chronic stage without any signs of arthritis. Strikingly, deletion of key adenosine-generating enzyme, ecto-5′-nucleotidase/CD73, was accompanied by significantly enhanced joint swelling in borrelia-infected CD73-deficient C57BL/6 mice. Collectively, these data suggest that insufficient basal adenosine level and/or pathogen-induced disordered lymphoid purine homeostasis may serve as important prerequisite for promotion of inflammatory responses and further host’s commitment to persistence of bacterial infection and arthritis development.
Kaposi’s Sarcoma-Associated Herpesvirus K3 and K5 Proteins Block Distinct Steps in Transendothelial Migration of Effector Memory CD4+ T Cells by Targeting Different Endothelial Proteins
Authors: Manes Thomas D. , Hoer Simon , Muller William A. , Lehner Paul J. , Pober Jordan S.
Published: April 2010

ORFK3 (K3) and ORFK5 (K5) are Kaposi’s sarcoma-associated herpesvirus-encoded E3 ubiquitin ligases that differentially reduce surface expression of various proteins in infected cells. In this study, we describe their effects on human dermal microvascular endothelial cells (ECs), a natural target of Kaposi’s sarcoma-associated herpesvirus infection. TNF-treated human dermal microvascular ECs transduced to express K5 show reduced capacity to capture effector memory (EM) CD4+ T cells under conditions of venular shear stress. K5 but not K3 transduction significantly reduces ICAM-1 expression and the inhibition of T cell capture was phenocopied by small interfering RNA knockdown of ICAM-1 and by anti–ICAM-1 Ab blocking. Cotransduction with an ICAM-1 truncated construct not subject to K5 ubiquitylation restored EM CD4+ T cell capture. K3 transductants effectively capture EM CD4+ T cells, but fail to support their transendothelial migration (TEM) in response to TCR engagement by superantigen presented by the ECs, leaving intact chemokine-dependent TEM. K3 but not K5 transduction significantly reduces PECAM-1 expression, and the effect on TCR-induced TEM is phenocopied by small interfering RNA knockdown of PECAM-1 and by anti–PECAM-1 Ab blocking. TCR-dependent TEM was restored in K3 transductants cotransduced to express a mutant of PECAM-1 not subject to K3-induced ubiquitylation. EM CD4+ T cells lack any known PECAM-1 counter receptor, but heterophilic engagement of PECAM-1 can involve glycosaminoglycans. In addition, TCR-induced TEM, but not chemokine-induced TEM, appears to involve a heparan- or chondroitin-like molecule on T cells. These results both identify specific roles of K5 and K3 in immune evasion and further differentiate the processes of inflammatory chemokine- versus TCR-dependent recruitment of human EM CD4+ T cells.
Multiple RNA Surveillance Mechanisms Cooperate to Reduce the Amount of Nonfunctional Igκ Transcripts
Authors: Chemin Guillaume , Tinguely Aurélien , Sirac Christophe , Lechouane Fabien , Duchez Sophie , Cogné Michel , Delpy Laurent
Published: April 2010

Random V(D)J junctions ensure that the diversity of the Ig primary repertoire is adapted to the vast heterogeneity of Ags. In two-thirds of cases, recombination between variable segments induces a frameshift in the open reading frame and generates a premature termination codon. In B cells harboring biallelic V(D)J rearrangement of Ig genes, transcription is known to occur on both the functional and nonfunctional alleles, generating considerable amounts of primary transcripts with out-of-frame V regions. In this study, we analyzed in cell lines and primary B cells the RNA surveillance of nonfunctional Igκ transcripts arising from nonproductive rearrangement. We demonstrated that splicing inhibition, nonsense-mediated decay and nonsense-altered splicing each have an individual partial effect that together associate into an efficient surveillance machinery, downregulating nonfunctional Igκ mRNA. Moreover, we provide evidence that the RNA surveillance efficiency increases throughout B cell development. Whereas splicing inhibition remains constant in most cell lines, differences in nonsense-mediated decay and nonsense-altered splicing are responsible for the higher RNA surveillance observed in plasma cells. Altogether, these data show that nonfunctionally rearranged alleles are subjected to active transcription but that multiple RNA surveillance mechanisms eradicate up to 90% of out-of-frame Igκ mRNA.
At Homeostasis Filarial Infections Have Expanded Adaptive T Regulatory but Not Classical Th2 Cells
Authors: Metenou Simon , Dembele Benoit , Konate Siaka , Dolo Housseini , Coulibaly Siaka Y. , Coulibaly Yaya I. , Diallo Abdallah A. , Soumaoro Lamine , Coulibaly Michel E. , Sanogo Dramane , Doumbia Salif S. , Traoré Sekou F. , Mahanty Siddhartha , Klion Amy , Nutman Thomas B.
Published: April 2010

Despite the well-documented immune suppression associated with human helminth infections, studies characterizing the immune response at the single-cell level are scanty. We used multiparameter flow cytometry to characterize the type of effector (Th1, Th2, and Th17) and regulatory (natural T regulatory cells [nTregs] and adaptive Treg cells [aTreg/type 1 regulatory cells (Tr1s)]) CD4+ and CD8+ T cells in filaria-infected (Fil+) and -uninfected (Fil−) individuals at homeostasis (in the absence of stimulation). Frequencies of CD4+ lymphocytes spontaneously producing IL-4, IL-10, and IL-17A were significantly higher in Fil+, as were those of IL-10+/IL-4+ double-producing CD4+ cells. Interestingly, frequencies of Th17 and aTreg/Tr1s but not classical Th1 or Th2 cells were significantly increased in Fil+ compared to Fil− individuals. Although the frequency of nTreg was increased in Fil+, IL-10 was overwhelmingly produced by CD4+CD25− cells. Moreover, the concentration of IL-10 produced spontaneously in vitro strongly correlated with the integrated geometric mean fluorescence intensity of IL-10–producing aTreg/Tr1s in Fil+. Together, these data show that at steady state, IL-10–producing aTreg/Tr1 as well as nTreg and effector Th17 CD4+ cells are expanded in vivo in human filarial infections. Moreover, we have established baseline ex vivo frequencies of effector and Tregs at homeostasis at a population level.
TAp63 Regulates VLA-4 Expression and Chronic Lymphocytic Leukemia Cell Migration to the Bone Marrow in a CD74-Dependent Manner
Authors: Binsky Inbal , Lantner Frida , Grabovsky Valentin , Harpaz Nurit , Shvidel Lev , Berrebi Alain , Goldenberg David M. , Leng Lin , Bucala Richard , Alon Ronen , Haran Michal , Shachar Idit
Published: April 2010

The hallmark of chronic lymphocytic leukemia (CLL) is the relentless accumulation of mature lymphocytes, mostly due to their decreased apoptosis. CD74 was recently shown to serve as a survival receptor on CLL cells. In this study, we show that stimulation of CD74 with its natural ligand, migration inhibitory factor, initiates a signaling cascade that results in upregulation of TAp63, which directly regulates CLL survival. In addition, TAp63 expression elevates the expression of the integrin VLA-4, particularly during the advanced stage of the disease. Blocking of CD74, TAp63, or VLA-4 inhibits the in vivo homing of CLL cells to the bone marrow (BM). Thus, CD74 and its target genes TAp63 and VLA-4 facilitate migration of CLL cells back to the BM, where they interact with the supportive BM environment that rescues them from apoptosis. These results could form the basis of novel therapeutic strategies aimed at blocking homing of CLL cells in their return to the BM and attenuating their survival.
TLR4 Is a Negative Regulator in Noninfectious Lung Inflammation
Authors: Zhao Hang , Leu Shaw-Wei , Shi Liyun , Dedaj Rejmon , Zhao Gaofeng , Garg Hari G. , Shen Lianjun , Lien Egil , Fitzgerald Katherine A. , Shiedlin Aviva , Shen Huahao , Quinn Deborah A. , Hales Charles A.
Published: April 2010

Low m.w. hyaluronan (LMW HA) has been shown to elicit the expression of proinflammatory cytokines and chemokines in various cells in vitro. However, the effects of this molecule in vivo are unknown. In this study, we report that intratracheal administration of LMW HA (200 kDa) causes inflammation in mouse lung. A lack of TLR4 is associated with even stronger inflammatory response in the lung as shown by increased neutrophil counts and elevated cytokine and chemokine concentrations. We also demonstrate that TLR4 anti-inflammatory signaling is dependent upon a MyD88-independent pathway. TLR4-mediated IL-1R antagonist production plays a negative regulatory role in LMW HA (200 kDa) induced lung inflammation. These data provide a molecular level explanation for the function of TLR4 in LMW HA (200 kDa)-induced lung inflammation, as inhibition of the β form of pro–IL-1 promotes an anti-inflammatory response.
Lower Body Positive Pressure Application with an Antigravity Suit in Acute Carotid Occlusion
Authors: Berthet Karine , Lukaszewicz Anne Claire , Bousser Marie-Germaine , Payen Didier
Published: April 2010

The challenge in acute stroke is still to reperfuse as early as possible the ischemic territory. Since fibrinolytic therapies have a limited window with potential risk of bleeding, having a nonpharmacologic mean to recruit vessels in area surrounding necrosis might be useful. We propose here to use antigravity suit inflated at “venous” pressure levels to shift blood towards thoracic and brain territories. We report two cases of spectacular clinical recovery after acute carotid occlusion.
Cost‐Efficient Metal–Ceramic Composites—Novel Foam‐Preforms, Casting Processes and Characterisation
Authors: Standke Gisela , Müller Thorsten , Neubrand Achim , Weise Jörg , Göpfert Mirko
Published: April 2010

Because of their dissatisfactory cost‐performance ratio metal matrix composites (MMCs) are still not established in industry, although they show improved properties compared to pure metals in some application fields. The present paper describes the development of enhanced MMCs based on silicon carbide (SiC) foams made by the Schwartzwalder process. Therefore, foams with cell sizes of 30, 45 and 60 ppi based on pressure less sintered SiC (SSiC) were developed. They were coated with layers of coarse SiC particles, which form a rough strut surface. The ceramic content of the foams could be increased to values of 20–30 mass%. Additionally, foam preforms based on clay‐bonded SiC (as they are known from molten metal infiltration) were tested.

The preforms were infiltrated with aluminium alloys AlSi9Cu3 and AlSi7Mg0.6 and cast iron EN‐GJSA‐XNiCr35‐5‐2 and EN‐GJL‐250. For aluminium alloys high pressure die casting (HPC) as well as gravity casting was applied, whereas iron was only infiltrated by gravity casting.

For HPC an excellent interlocking of metal and preform was observed because of the microporosity of the rough surface of the SSiC foam struts. By the use of gravity casting preform cells up to 45 ppi could be well infiltrated. Microporosity in the ceramic coating and the typical hollow struts of the foams did not show metal infiltration.

Even by use of moderate ceramic volume fractions pressure‐infiltrated aluminium matrix composites showed a high specific stiffness of up to E/ρ = 42 GPa cm3 g−1 compared to conventional Al or Mg alloys (E/ρ = 25–27 GPa cm3 g−1). Ceramic foam based MMCs produced by pressure less casting showed no advantages in mechanical properties compared to pure metals. Nevertheless it can be expected that they can provide improved wear resistance and lower thermal expansion coefficients.
Modelling of Hot Ductility during Solidification of Steel Grades in Continuous Casting – Part II
Authors: Böttger Bernd , Stratemeier Sonja , Subasic Emir , Göhler Klans , Steinbach Ingo , Senk Dieter
Published: April 2010

In continuous casting, the probability of hot cracks developing strongly depends on the local solidification process and the microstructure formation. In ref. 1, an integrative model for hot cracking of the initial solid shell is developed. This paper focuses on solidification modelling, which plays an important role in the integrated approach. Solidification is simulated using a multiphase‐field model, coupled online to thermodynamic and diffusion databases and using an integrated 1D temperature solver to describe the local temperature field. Less‐complex microsegregation models are discussed for comparison. The results are compared to EDX results from strand samples of different steel grades.
Physical and Numerical Simulation of Cold Rolling of an AlFeSi Alloy in Consideration of Static Recovery
Authors: Heering Christoph , Li Xiaoli , Bambach Markus , Hirt Gerhard
Published: April 2010

The influence of static recovery on the yield stress of AA8079 was investigated in lab‐scale cold rolling experiments. The yield stress of AA8079 in the cold rolling process is affected by static recovery, but the softening caused by static recovery is completely compensated in the subsequent cold rolling pass. Thus, the effect of static recovery on the yield stress of the final product is of minor importance. For the TPM, the kinetics of static recovery of the AlFeSi alloy AA8079 were determined for different temperatures and strain rates. The measured softening kinetics were then implemented in the physically based flow stress model 3IVM+. This flow stress model was extended with an empirical approach for static recovery to enable the through‐process modeling of cold‐rolled aluminum in consideration of static recovery. Future work will focus on physically based modeling of static recovery without using empirical approaches.
Simulation of Welding and Distortion in Ship Building
Authors: Rieger Thomas , Gazdag Stefan , Prahl Ulrich , Mokrov Oleg , Rossiter Eduardo , Reisgen Uwe
Published: April 2010

Simulation tools will continue to gain importance for both scientific investigations and industrial applications. This further applies to welding technology. The present work focuses on the simulation of distortions due to the welding of stiffeners on heavy plates in shipbuilding. An equivalent heat source (EHS) was computed by the software SimWeld to describe the energy input caused by welding. The EHS was combined with an FEM simulation of the global structure in the commercial program SYSWELD. Therefore an interface between the SimWeld platform and SYSWELD was implemented. The simulation results were compared with a welded demonstrator. The predicted displacements correlate closely with the experimental data. Using the combined approach the quality of the prediction was significantly improved against the typical method of heat source parameter identification, which is based on experimental results. The results allow for the optimization of welding sequences and for the minimization of buckling in shipbuilding.
Designed Multifunctional Nanocomposites for Biomedical Applications
Authors: Yiu Humphrey H. P. , Niu Hong‐jun , Biermans Ellen , van Tendeloo Gustaaf , Rosseinsky Matthew J.
Published: April 2010

The assembly of multifunctional nanocomposite materials is demonstrated by exploiting the molecular sieving property of SBA‐16 nanoporous silica and using it as a template material. The cages of the pore networks are used to host iron oxide magnetic nanoparticles, leaving a pore volume of 0.29 cm3 g−1 accessible for drug storage. This iron oxide–silica nanocomposite is then functionalized with amine groups. Finally the outside of the particle is decorated with antibodies. Since the size of many protein molecules, including that of antibodies, is too large to enter the pore system of SBA‐16, the amine groups inside the pores are preserved for drug binding. This is proven using a fluorescent protein, fluorescein‐isothiocyanate‐labeled bovine serum albumin (FITC‐BSA), with the unreacted amine groups inside the pores dyed with rhodamine B isothiocyanate (RITC). The resulting nanocomposite material offers a dual‐targeting drug delivery mechanism, i.e., magnetic and antibody‐targeting, while the functionalization approach is extendable to other applications, e.g., fluorescence–magnetic dual‐imaging diagnosis.
Grayscale Photopatterning of an Amorphous Polymer Thin Film Prepared by Photopolymerization of a Bisanthracene‐Functionalized Liquid‐Crystalline Monomer
Authors: Kihara Hideyuki , Motohashi Masashi , Matsumura Kazunari , Yoshida Masaru
Published: April 2010

A method for grayscale photopatterning of an amorphous polymer film derived from a bisanthracene‐functionalized liquid‐crystalline monomer is developed. Solution photopolymerization of a monomer with two anthracene moieties, one at each end, affords an amorphous polymer. A combination of irradiation with patterned UV light and heating results in photopatterning on thin films prepared from the polymer. On non‐irradiated areas of the film, the polymer reverts to the monomer owing to the thermal back‐reaction of the anthracene photodimer, forming an ordered phase. On irradiated areas remaining in the amorphous phase, the thermal back‐reaction is suppressed. This phenomenon results in a clear contrast and visual images on the film under polarized light. Grayscale photopatterning is also made possible for the solution‐polymerized polymer by controlling the intensity of exposure. In addition, rewritable photopatterning can be achieved by melt photopolymerization of the monomer. The new photopatterning is essentially nondestructive because it needs neither image development nor anthracene‐excitation light for reading.
Phylogeography of the Angolan black and white colobus monkey, Colobus angolesnsis palliatus, in Kenya and Tanzania
Authors: McDonald Monica M. , Hamilton Healy
Published: April 2010

Little is known about genetic variation in the 6–8 subspecies of Colobus angolensis, currently distinguished by pelage differences. We present a comparative genetic analysis of one of these subspecies, C. a. palliatus, in Kenya and Tanzania that assesses evolutionary relationships and patterns of mitochondrial genetic diversity in 103 individuals across its geographic range. Fecal samples from approximately 156 individuals were collected in four localities: (1) Diani Forest, Kenya; (2) Shimoni, Kenya; (3) Udzungwa Mountains National Park, Eastern Arc Mountains, Tanzania; and (4) Mount Rungwe, Southern Highlands, Tanzania. These samples represent at least six groups, with 5–15 samples from each. Comparative sequence analysis of a 1,795 base pair mtDNA fragment revealed 19 unique haplotypes in four populations. Phylogenetic analyses suggest that sampled Kenyan haplotypes are paraphyletic, with one Kenyan haplotype basal to all other sampled haplotypes. Analysis of molecular variance (AMOVA) suggests high levels of genetic variation among populations (ΦST 0.72, P<0.001). Genetic data are concordant with a subspecies level differentiation between C. a. palliatus populations in Kenya and those in Central and southern Tanzania, as earlier suggested based on pelage differences. This study highlights the evolutionary distinctiveness of Kenyan populations of C. a. palliatus relative to Tanzanian populations. Although C. a. palliatus habitat in Tanzania is currently better protected than in Kenya, our results suggest Kenyan and Tanzanian populations should be considered distinct units, and the protection of C. a. palliatus habitat in Kenya, as well as habitat connectivity between Kenyan populations, should be prioritized for conservation and management. Am. J. Primatol. 72:715–724, 2010. © 2010 Wiley‐Liss, Inc.
Role of carboxyl pendant groups of medium chain length poly(3‐hydroxyalkanoate)s in biomedical temporary applications
Authors: Renard E. , Timbart L. , Vergnol G. , Langlois V.
Published: April 2010

The poly(3‐hydroxyoctanoate) (PHO) is a biodegradable polyester containing hydrophobic side chains. One way to obtain more hydrophilic polyester consisted in the introduction of polar groups in the side chains. Carboxyl groups (PHO75COOH25) were introduced by chemical modifications. The role of carboxyl groups was investigated in the first part as potential support for cell seeding by studying the cell adhesion and proliferation, and in the second part as potential drug carrier by comparing the abilities of PHO and PHO75COOH25 to form degradable particles. Measurements of human bladder RT112 cells adhesion were done with or without collagen IV. Adhesive RT112 cells were counted by a colorimetric MTT test. The results showed that the COOH pendant groups of PHO75COOH25 films promoted cell adhesion after 4 h of incubation. The proliferation of cells is not improved after 4 days of incubation because of a reorganization of macromolecular chains and reorientation of COOH groups. This surface restructuration when the film was in contact with water was showed by contact angle measurements. We showed that the presence of COOH groups modified the hydrophobic/hydrophilic balance and enhanced the formation of particles. Stable lyophilisable particles were then obtained with diblock copolymer P(HO75COOH25‐b‐CL); the caprolactone block (CL) was necessary to improve particles stability. The results showed that the release of doxorubicin from the particles is enhanced in presence of hydrophilic and degradable block (PHO75COOH25). It was possible to obtain a degradable functional polyester based on PHO with carboxyl pendant groups to improve degradation rate by simple hydrolysis required for drug delivery systems. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Pectin grafted poly(N‐vinylpyrrolidone): Optimization and in vitro controllable theophylline drug release
Authors: Fares Mohammad M. , Assaf Shereen M. , Abul‐Haija Yousef M.
Published: April 2010

The present article describes preparation, optimization, and characterization of pectin grafted polyvinylpyrrolidone hydrogels followed by controllable theophylline drug release. The gels were prepared in the presence of N,N′–methylenebisacrylamide (MBAA) crosslinker and ceric ammonium nitrate (CAN) initiator under N2 atmosphere. Optimum conditions, in terms of percent of grafting (%G), were determined as follows: Pectin = 1.0 g, [NVP] = 2.81 mM, [MBAA] = 0.65 mM, [CAN] = 0.073 mM, polymerization temperature = 30°C and time = 4.0 hrs. Hydrogels were characterized by FTIR, TGA, DSC, XRD, and SEM. In vitro controllable release of theophylline model drug was studied using different N‐vinylpyrrolidone monomer to MBAA crosslinker ratio (i.e., [NVP]/[MBAA] ratios) and different polymerization temperatures at two pH values, namely 5.5 and 7.4. The optimum conditions for colon‐targeted vehicles that could provide the least theophylline release at pH 5.5, and the most theophylline release at pH 7.4, were as follows: [NVP]/[MBAA] = 4.33, polymerization temperature = 10°C and %G = 62.2. Such promising hydrogel characteristics may play the key role in many future drug release implementations. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Poly(lactic acid)/soluble eggshell membrane protein blend films: Preparation and characterization
Authors: Xiong Xi , Li Qiang , Lu Jian‐Wei , Guo Zhao‐Xia , Yu Jian
Published: April 2010

Poly(lactic acid) (PLA), one of the most commonly used synthetic biodegradable polymers having good mechanical properties, is blended with soluble eggshell membrane protein (SEP) by solution casting from hexafluoroisopropanol to improve the mechanical properties of SEP. When PLA/SEP proportion is 9 : 1, the cast film has much better mechanical properties than neat SEP film and significantly improved biocompatibility compared to neat PLA film, as demonstrated by tensile tests and cell culture of NIH3T3. The PLA/SEP blend films were further characterized by field emission gun scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, differential scanning calorimetry, X‐ray diffraction, and contact angle measurements. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A deadlock prevention approach for a class of timed Petri nets using elementary siphons
Authors: Guo Jinwei , Li Zhiwu
Published: April 2010

To solve the problem of deadlock prevention for timed Petri nets, an effective deadlock prevention policy based on elementary siphons is proposed in this paper. Without enumerating reachable markings, deadlock prevention is achieved by adding monitors for elementary siphons, increasing control depth variables when necessary, and removing implicit, liveness‐restricted and redundant control places. The final supervisor is live. First, a timed Petri net is stretched into a stretched Petri net (SPN). Unchanging the system performance, each transition in the SPN has a unit delay time. Then the siphon‐control‐based approach is applied. Monitors computed according to the marking constraints are added to the SPN model to ensure all strict minimal siphons in the net invariant‐controlled. A liveness‐enforcing supervisor with simple structure can be obtained by reverting the SPN into a TdPN. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Robust unscented Kalman filtering for nonlinear uncertain systems
Authors: Xiong K. , Wei C. L. , Liu L. D.
Published: April 2010

A derivative‐free robust Kalman filter algorithm is proposed for nonlinear uncertain systems. The unscented transform (UT) is adopted instead of the linearization technique to obtain the solution of theH∞filter Riccati equation. A robust unscented Kalman filter (RUKF) is derived to guarantee an optimized upper bound on the estimation error covariance despite the model uncertainties and the approximation error of the UT. The proposed algorithm is applied to a satellite attitude determination system. Simulation results show that the RUKF is more effective than the unscented Kalman filter (UKF) in cases where alignment errors are present. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
A pedagogical Web service‐based interactive learning environment for a digital filter design course: An evolutionary approach
Authors: Wu Wen‐Hsiung , Chen Wei‐Fan , Wang Tsung‐Li , Su Te‐Jen
Published: April 2010

The course of digital filter design in electronic/electrical engineering involves complicated mathematical equations and dynamic waveform variations. It is a consensus among educators that using simulation tools assist in improving students' learning experiences. Previous studies on system simulation seemed to lack an appropriate approach to design such a course. Few emphasized the design of an interactive learning environment by using an evolutionary approach. This study integrated the design concept of an evolutionary approach and Web service‐based technology into a simulation system entitled Pedagogical Web Service‐Based Interactive Learning Environment (PEWSILE) was introduced. The PEWSILE system contained two interactive learning environments—a simple system and an advanced system. It offered a total of six pedagogical Web services. The simple interactive learning environment included text/color‐based services, and text/color/diagram‐based services. The advanced interactive learning environment included batch‐based, interval change‐based, comparison‐based, and scroll bar‐based services. The study also assessed the students' performance in six pedagogical Web services covering interaction and overall use, usefulness, and intention to use through a questionnaire survey and subsequent interviews. Three significant findings were reported. For example, in the advanced interactive learning environment, the designs of interval change‐based and comparison‐based services make it easier to observe differences in the outcome of parameter change, while batch‐based services lacks the element of waveform comparison. In sum, the findings in this study provide helpful implications in designing engineering educational software. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 423–433, 2010; View this article online at wileyonlinelibrary.com; DOI 10.1002/cae.20163
Visual interactive environment for study the power electronics using PSCAD‐EMTDC simulation program
Authors: Pănoiu Caius , Pănoiu Manuela , Muscalagiu Ionel , Iordan Anca
Published: April 2010

Informational society needs major changes in the educational programs, being necessary to prepare teachers from all fields, in such way to use the information technologies in computer assisted learning. The computer, as auxiliary element of the teacher, is used since few decades, but the new technologies appeared in computer science lead to the necessity to adapt the learning/teaching methodologies in such way to be based increasingly on information technology. This paper presents a software package, which can be used as educational software, for study the power electronics. This study deals with the simulation of power electronic circuits by using PSCAD EMTDC software. Since the equations and functions can be represented in blocks, simulation method is simple and versatile. The PSCAD models of single and three‐phase rectifiers, PWM choppers and inverters, AC choppers, are developed and performance waveforms are obtained. This study would be useful for obtaining a quick solution for, power electronic networks and for more complex systems containing power electronic circuits. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 18: 469–475, 2010; View this article online atwileyonlinelibrary.com; DOI 10.1002/cae.20197
The Identification of a Novel Natural Activator of p300 Histone Acetyltranferase Provides New Insights into the Modulation Mechanism of this Enzyme
Authors: Dal Piaz Fabrizio , Tosco Alessandra , Eletto Daniela , Piccinelli Anna L. , Moltedo Ornella , Franceschelli Silvia , Sbardella Gianluca , Remondelli Paolo , Rastrelli Luca , Vesci Loredana , Pisano Claudio , De Tommasi Nunziatina
Published: April 2010

Many severe human pathologies are related to alterations of the fine balance between histone acetylation and deacetylation; because not all such diseases involve hypoacetylation, but also hyperacetylation, compounds able to enhance or repress the activities of histone acetyltransferases (HATs) could be promising therapeutic agents. We evaluated in vitro and in cell the ability of eleven natural polyisoprenylated benzophenone derivatives to modulate the HAT activity of p300/CBP, an enzyme that plays a pivotal role in a variety of cellular processes. Some of the tested compounds bound efficiently to the p300/CBP protein: in particular, guttiferone A, guttiferone E and clusianone inhibit its HAT activity, whereas nemorosone showed a surprising ability to activate the enzyme. The ability of nemorosone to penetrate cell membranes and modulate histone acetylation into the cell together with its high affinity for the p300/CBP enzyme made this compound a suitable lead for the design of optimized anticancer drugs. Besides, the studies performed at a cellular and molecular level on both the inhibitors and the activator provided new insights into the modulation mechanism of p300/CBP by small molecules.
Modulation of Stacking Interactions by Transition‐Metal Coordination: Ab Initio Benchmark Studies
Authors: Mutter Shaun T. , Platts James A.
Published: April 2010

A series of ab initio calculations are used to determine the CH⋅⋅⋅π and π⋅⋅⋅π‐stacking interactions of aromatic rings coordinated to transition‐metal centres. Two model complexes have been employed, namely, ferrocene and chromium benzene tricarbonyl. Benchmark data obtained from extrapolation of MP2 energies to the basis set limit, coupled with CCSD(T) correction, indicate that coordinated aromatic rings are slightly weaker hydrogen‐bond acceptors but are significantly stronger hydrogen‐bond donors than uncomplexed rings. It is found that π⋅⋅⋅π stacking to a second benzene is stronger than in the free benzene dimer, especially in the chromium case. This is assigned, by use of energy partitioning in the local correlation method, to dispersion interactions between metal d and benzene π orbitals. The benchmark data is also used to test the performance of more efficient theoretical methods, indicating that spin‐component scaling of MP2 energies performs well in all cases, whereas various density functionals describe some complexes well, but others with errors of more than 1 kcal mol−1.
Gas‐Phase Energetics of Reductive Elimination from a Palladium(II) N‐Heterocyclic Carbene Complex
Authors: Couzijn Erik P. A. , Zocher Eva , Bach Andreas , Chen Peter
Published: April 2010

Energy‐resolved collision‐induced dissociation experiments using tandem mass spectrometry are reported for an phenylpalladium N‐heterocyclic carbene (NHC) complex. Reductive elimination of an NHC ligand as a phenylimidazolium ion involves a barrier of 30.9(14) kcal mol−1, whereas competitive ligand dissociation requires 47.1(17) kcal mol−1. The resulting three‐coordinate palladium complex readily undergoes reductive CC coupling to give the phenylimidazolium π complex, for which the binding energy was determined to be 38.9(10) kcal mol−1. Density functional calculations at the M06‐L//BP86/TZP level of theory are in very good agreement with experiment. In combination with RRKM modeling, these results suggest that the rate‐determining step for the direct reductive elimination process switches from the CC coupling step to the fragmentation of the resulting σ complex at low activation energy.
Sonication‐Assisted Fabrication and Post‐Synthetic Modifications of Graphene‐Like Materials
Authors: Cravotto Giancarlo , Cintas Pedro
Published: April 2010

Chemistry of and with graphene constitutes a rapidly evolving field that holds much promise for the generation of advanced materials with salient, and often unique, properties and potential applications in different fields. However, reliable, mild, and scalable methods to produce this layered carbonaceous material represent an important bottleneck and are critical for progress in this research area to continue. In this context, the use of ultrasound has become a routine and indispensable step in numerous synthetic protocols, even though most researchers usually overlook the science behind it. This minireview provides some fundamentals on the interaction of sound waves with matter and equally illustrates how sonication assists further synthetic decorations under benign conditions.
On the Structural Chemistry of γ‐Brasses: Two Different Interpenetrating Networks in Ternary F‐Cell Pd–Zn–Al Phases
Authors: Thimmaiah Srinivasa , Miller Gordon J.
Published: April 2010

Novel ternary phases, (Pd1−xZnx)18(Zn1−yAly)86−δ (0≤x≤0.162, 0.056≤y≤0.088, 0≤δ≤4), which adopt a superstructure of the γ‐brass type (called γ′‐brass), have been synthesized from the elements at 1120 K. Single‐crystal X‐ray structural analysis reveals a phase width (F$\bar 4$3m, a=18.0700(3)–18.1600(2) Å, Pearson symbols cF400–cF416), which is associated with structural disorder based on both vacancies as well as mixed site occupancies. These structures are constructed of four independent 26‐atom γ‐clusters per primitive unit cells and centered at the four special positions A (0, 0, 0), B (1/4, 1/4, 1/4), C (1/2, 1/2, 1/2) and D (3/4, 3/4, 3/4). Two of these, centered at B and C, are completely ordered Pd4Zn22 clusters, whereas the other two, centered at A and D, contain all structural disorder in the system. According to our single‐crystal X‐ray results, Al substitutions are restricted to the A‐ and D‐centered clusters. Moreover, the outer tetrahedron (OT) site of the 26‐atom cluster at D is completely vacant at the Al‐rich boundary of these phases. Electronic structure calculations, using the tight‐binding linear muffin‐tin orbital atomic‐spheres approximation (TB‐LMTO‐ASA) method, on models of these new, ternary γ′‐brass phases indicate that the observed chemical compositions and atomic distributions lead to the presence of a pseudogap at the Fermi level in the electronic density of states curves, which is consistent with the Hume‐Rothery interpretation of γ‐brasses, in general.
Surface‐Modified Upconverting Microparticles and Nanoparticles for Use in Click Chemistries
Authors: Mader Heike S. , Link Martin , Achatz Daniela E. , Uhlmann Katrin , Li Xiaohua , Wolfbeis Otto S.
Published: April 2010

A method is described for modifying the surface of upconverting microparticles (UCμPs) and nanoparticles (UCNPs) such that they become amenable to click chemistry. Respective reagents are presented and used in both kinds of particles, either directly or in combination with tetraethoxysilane. The particles also were labeled by using the click reaction, a) with fluorophores to yield materials that have emission colors that depend on the wavelength of excitation; b) with maleinimido groups (so to obtain labels for thiols), and c) with biotin (to make them useful for affinity studies based on the biotin–streptavidin system). We believe that both the UCμPs and UCNPs have the potential of being used in numerous areas including upconversion imaging, biolabeling, and derivatization, but also in encoding and security.
ChemInform Abstract: Lithium Argyrodites with Phosphorus and Arsenic: Order and Disorder of Lithium Atoms, Crystal Chemistry, and Phase Transitions.
Authors: Kong Shiao‐Tong , Deiseroth Hans‐Joerg , Reiner Christof , Guen Oezguel , Neumann Elmar , Ritter Clemens , Zahn Dirk
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Finally Fulfilling Wade′s Rules: The C4v Symmetric Polycation Bi95+ in the Polar Structure of Bi18Sn7Br24 = (Bi95+)2 [Sn7Br2410‐].
Authors: Wahl Bernhard , Ruck Michael
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Structure Investigations of α‐ and β‐Ammoniumdithiocarbamate NH4CS2NH2 and the Role of Hydrogen Bonding.
Authors: Teske Christoph L. , Bensch Wolfgang
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Orthorhombic HP‐PrO2 — High‐Pressure Synthesis and Crystal Structure.
Authors: Haberer Almut , Huppertz Hubert
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Pseudobinary Section La3In5—La3Pb5: Synthesis, Structural Chemistry, Phases Widths, and Chemical Bonding.
Authors: Duerr Ines , Roehr Caroline
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Effects of Se Doping on Thermoelectric Properties of Zn4Sb3 at Low‐Temperatures.
Authors: Pan L. , Qin X. Y. , Liu M.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Structure of Molybdenum Tantalum Oxide, Mo2Ta2O11.
Authors: Berendts Stefan , Stork Alexandra , Irran Elisabeth , Lerch Martin
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Growth of Barium Rhenates from Hydroxide fluxes.
Authors: Bharathy M. , Smith M. D. , zur Loye H.‐C.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis, Structure and Chemical Bonding of CaCo2Si2 and BaCo2Ge2 — Two New Compounds with ThCr2Si2 Structure Type.
Authors: Siggelkow Lisa , Hlukhyy Viktor , Faessler Thomas F.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Partial Anion Exchange in Ag23Te12X: The Solid Solutions Ag23Te12Cl1‐xBrx, Ag23Te12Br1‐yIy and Ag23Te12Cl1‐zIz.
Authors: Osters Oliver , Nilges Tom
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Step‐by‐Step Synthesis of the Endohedral Stannaspherene [Ir@Sn12]3‐ via the Capped Cluster Anion [Sn9Ir(cod)]3‐.
Authors: Wang Jian‐Qiang , Stegmaier Saskia , Wahl Bernhard , Faessler Thomas F.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Metal‐Rich Phosphide Lu3Ir7P5 — Flux Growth and Crystal Chemistry.
Authors: Pfannenschmidt Ulrike , Rodewald Ute Ch. , Poettgen Rainer
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Design and Synthesis of Chiral Imidazolidine‐Pyridine Ligands.
Authors: Arai Takayoshi , Suzuki Kuniko
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: N‐Heterocyclic Carbene‐Catalyzed Enantioselective Mannich Reactions with α‐Aryloxyacetaldehydes.
Authors: Kawanaka Yasufumi , Phillips Eric M. , Scheidt Karl A.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Catalyzed Catalysis Using Carbophilic Lewis Acidic Gold and Lewis Basic Palladium: Synthesis of Substituted Butenolides and Isocoumarins.
Authors: Shi Yili , Roth Katrina E. , Ramgren Stephen D. , Blum Suzanne A.
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Mixed Disproportionation versus Radical Trapping in Titanocene(III)‐Promoted Epoxide Openings.
Authors: Justicia Jose , Jimenez Tania , Morcillo Sara P. , Cuerva Juan M. , Oltra J. Enrique
Published: April 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.