bluuebunny/crossref_metadata_2025 huggingface dataset:
The Cellular Amount of the Common γ-Chain Influences Spontaneous or Induced Cell Proliferation
Authors: Amorosi Stefania , Russo Ilaria , Amodio Giada , Garbi Corrado , Vitiello Laura , Palamaro Loredana , Adriani Marsilio , Vigliano Ilaria , Pignata Claudio
Published: February 2009

Mutations of the IL2RG encoding the common γ-chain (γc) lead to the X-linked SCID disease. Gene correction through ex vivo retroviral transduction restored the immunological impairment in the most of treated patients, although lymphoproliferative events occurred in five of them. Even though in two cases it was clearly documented an insertional mutagenesis in LMO2, it is conceivable that γc could have a role per se in malignant lymphoproliferation. The γc is a shared cytokine receptor subunit, involved also in growth hormone (GH) receptor signaling. Through short interfering RNA or using X-linked SCID B lymphoblastoid cell lines lacking γc, we demonstrate that self-sufficient growth was strongly dependent on γc expression. Furthermore, a correlation between γc amount and the extent of constitutive activation of JAK3 was found. The reduction of γc protein expression also reduced GH-induced proliferation and STAT5 nuclear translocation in B lymphoblastoid cell lines. Hence, our data demonstrate that γc plays a remarkable role in either spontaneous or GH-induced cell cycle progression depending on the amount of protein expression, suggesting a potential role as enhancing cofactor in lymphoproliferation.
Hantaan Virus Triggers TLR3-Dependent Innate Immune Responses
Authors: Handke Wiebke , Oelschlegel Robin , Franke Renate , Krüger Detlev H. , Rang Andreas
Published: February 2009

Immediately after viral infection, innate responses including expression of IFN-α/β and IFN-stimulated genes (ISGs) are elicited ubiquitously by recruitment of specific pathogen recognition receptors. The velocity to induce IFN-α/β and ISGs in response to an infection is often decisive for virulence. Interestingly, in primary endothelial cells ISGs are induced later by hantaviruses pathogenic to humans than those considered to be nonpathogenic or of low virulence. Here we demonstrate that pathogenic Hantaan (HTNV) and putatively nonpathogenic Prospect Hill hantavirus (PHV) differentially activate innate responses in the established cell lines A549 and HuH7. STAT1α phosphorylation was detectable 3 h after PHV inoculation but not within the first 2 days after HTNV inoculation. The velocity to induce the ISGs MxA and ISG15 correlated inversely with amounts of virus produced. Moreover, expression of the inflammatory chemokine CCL5 was also induced differentially. Both hantaviruses induced innate responses via TRAF3 (TNF receptor-associated factor 3), and TLR3 was required for HTNV-induced expression of MxA, but not for the MxA induction triggered by PHV. Infection of RIG-I-deficient HuH7.5 cells revealed that RIG-I (retinoic acid receptor I) was not necessary for induction of innate responses by PHV. Taken together, these data suggest that HTNV and PHV elicit different signaling cascades that converge via TRAF3. Early induction of antiviral responses might contribute to efficient elimination of PHV. Subsequent to clearance of the infection, innate responses most likely cease; vice versa, retarded induction of antiviral responses could lead to increased HTNV replication and dissemination, which might cause a prolonged inflammatory response and might contribute to the in vivo virulence.
Blockade of Indoleamine 2,3-Dioxygenase Protects Mice against Lipopolysaccharide-Induced Endotoxin Shock
Authors: Jung In Duk , Lee Min-Goo , Chang Jeong Hyun , Lee Jun Sik , Jeong Young-Il , Lee Chang-Min , Park Won Sun , Han Jin , Seo Su-Kil , Lee Sang Yong , Park Yeong-Min
Published: February 2009

Suppression of an excessive systemic inflammatory response is a promising and potent strategy for treating endotoxic sepsis. Indoleamine 2,3-dioxygenase (IDO), which is the rate-limiting enzyme for tryptophan catabolism, may play a critical role in various inflammatory disorders. In this study, we report a critical role for IDO in the dysregulated immune response associated with endotoxin shock. We found that IDO knockout (IDO−/−) mice and 1-methyl-d-tryptophan-treated, endotoxin-shocked mice had decreased levels of the cytokines, TNF-α, IL-6, and IL-12, and enhanced levels of IL-10. Blockade of IDO is thought to promote host survival in LPS-induced endotoxin shock, yet little is known about the molecular mechanisms that regulate IDO expression during endotoxin shock. In vitro and in vivo, IDO expression was increased by exogenous IL-12, but decreased by exogenous IL-10 in dendritic cells and splenic dendritic cells. Interestingly, whereas LPS-induced IL-12 levels in serum were higher than those of IL-10, the balance between serum IL-12 and IL-10 following challenge became reversed in IDO−/−- or 1-methyl-d-tryptophan-treated mice. Our findings demonstrate that the detrimental immune response to endotoxin shock may occur via IDO modulation. Restoring the IL-12 and IL-10 balance by blocking IDO represents a potential strategy for sepsis treatment.
The Development of Airway Hyperreactivity in T-bet-Deficient Mice Requires CD1d-Restricted NKT Cells
Authors: Kim Hye Young , Pichavant Muriel , Matangkasombut Ponpan , Koh Youngil I. , Savage Paul B. , DeKruyff Rosemarie H. , Umetsu Dale T.
Published: February 2009

T-bet−/− mice have been shown to have a profound deficiency in the ability to generate invariant NKT (iNKT) cells in the periphery due to a halt in terminal maturation, but despite this deficiency, T-bet−/− mice develop spontaneous airway hyperreactivity (AHR) and airway inflammation. Because in some situations the development of AHR requires the presence of iNKT cells, we sought to more clearly understand how AHR develops in T-bet−/− mice by examining T-bet−/− mice in several distinct mouse models of asthma, including spontaneous, OVA-induced and α-galactosylceramide (α-GalCer)-induced AHR. Surprisingly, we found that administration of α-GalCer, which very specifically activates iNKT cells, greatly increased the AHR response in the T-bet−/− mice. Moreover, in T-bet−/− mice, spontaneous AHR as well as AHR induced with OVA or α-GalCer were all eliminated by blocking CD1d, the restricting element of iNKT cells, using an anti-CD1d-blocking mAb. Although the number of the iNKT cells in T-bet−/− mice was reduced compared with that in wild-type mice, the remaining iNKT cells produced primarily IL-4 and IL-13, and only minimal amounts of IFN-γ. We conclude therefore that the AHR that develops in T-bet−/− mice is dependent on the presence of iNKT cells, and that whereas T-bet−/− have reduced numbers of iNKT cells, these are sufficient for the development of AHR.
Selective Priming and Expansion of Antigen-Specific Foxp3−CD4+ T Cells during Listeria monocytogenes Infection
Authors: Ertelt James M. , Rowe Jared H. , Johanns Tanner M. , Lai Joseph C. , McLachlan James B. , Way Sing Sing
Published: February 2009

The Foxp3-expressing subset of regulatory CD4+ T cells have defined Ag specificity and play essential roles in maintaining peripheral tolerance by suppressing the activation of self-reactive T cells. Similarly, during chronic infection, pathogen-specific Foxp3-expressing CD4+ T cells expand and actively suppress pathogen-specific effector T cells. Herein, we used MHC class II tetramers and Foxp3gfp knockin mice to track the kinetics and magnitude whereby pathogen-specific Foxp3+CD4+ and Foxp3−CD4+ cells are primed and expand after acute infection with recombinant Listeria monocytogenes (Lm) expressing the non-“self”-Ag 2W1S52–68. We demonstrate that Lm infection selectively primes proliferation, expansion, and subsequent contraction of Lm-specific Foxp3− effector CD4+ cells, while the numbers of Lm-specific Foxp3+CD4+ regulatory cells remain essentially unchanged. In sharp contrast, purified 2W1S52–68 peptide primes coordinated expansion of both Foxp3+ regulatory and Foxp3− effector T cells with the same Ag specificity. Taken together, these results indicate selective priming and expansion of Foxp3− CD4 T cells is a distinguishing feature for acute bacterial infection.
The Microenvironment of Germ Cell Tumors Harbors a Prominent Antigen-Driven Humoral Response
Authors: Willis Simon N. , Mallozzi Scott S. , Rodig Scott J. , Cronk Katherine M. , McArdel Shannon L. , Caron Tyler , Pinkus Geraldine S. , Lovato Laura , Shampain Kimberly L. , Anderson David E. , Anderson Richard C. E. , Bruce Jeffrey N. , O’Connor Kevin C.
Published: February 2009

Germ cell tumors are a heterogeneous group of neoplasms derived from residual primordial tissue. These tumors are commonly found in the brain, testes, or ovaries, where they are termed germinomas, seminomas, or dysgerminomas, respectively. Like several other tumor types, germ cell tumors often harbor an immune cell infiltrate that can include substantial numbers of B cells. Yet little is known about whether the humoral immune response affects germ cell tumor biology. To gain a deeper understanding of the role B cells play in this tumor family, we characterized the immune cell infiltrate of all three germ cell tumor subtypes and defined the molecular characteristics of the B cell Ag receptor expressed by tumor-associated B cells. Immunohistochemistry revealed a prominent B cell infiltrate in the microenvironment of all tumors examined and clear evidence of extranodal lymphoid follicles with germinal center-like architecture in a subset of specimens. Molecular characterization of the Ig variable region from 320 sequences expressed by germ cell tumor-infiltrating B cells revealed clear evidence of Ag experience, in that the cardinal features of an Ag-driven B cell response were present: significant somatic mutation, isotype switching, and codon insertion/deletion. This characterization also revealed the presence of both B cell clonal expansion and variation, suggesting that local B cell maturation most likely occurs within the tumor microenvironment. In contrast, sequences from control tissues and peripheral blood displayed none of these characteristics. Collectively, these data strongly suggest that an adaptive and specific humoral immune response is occurring within the tumor microenvironment.
Programming for CD8 T Cell Memory Development Requires IL-12 or Type I IFN
Authors: Xiao Zhengguo , Casey Kerry A. , Jameson Stephen C. , Curtsinger Julie M. , Mescher Matthew F.
Published: February 2009

Inflammation can have both positive and negative effects on development of CD8 T cell memory, but the relative contributions and cellular targets of the cytokines involved are unclear. Using CD8 T cells lacking receptors for IL-12, type I IFN, or both, we show that these cytokines act directly on CD8 T cells to support memory formation in response to vaccinia virus and Listeria monocytogenes infections. Development of memory to vaccinia is supported predominantly by IL-12, whereas both IL-12 and type I IFN contribute to memory formation in response to Listeria. In contrast to memory formation, the inability to respond to IL-12 or type I IFN had a relatively small impact on the level of primary expansion, with at most a 3-fold reduction in the case of responses to Listeria. We further show that programming for memory development by IL-12 is complete within 3 days of the initial naive CD8 T cell response to Ag. This programming does not result in formation of a population that expresses killer cell lectin-like receptor G1, and the majority of the resulting memory cells have a CD62Lhigh phenotype characteristic of central memory cells. Consistent with this, the cells undergo strong expansion upon rechallenge and provide protective immunity. These data demonstrate that IL-12 and type I IFN play an essential early role in determining whether Ag encounter by naive CD8 T cells results in formation of a protective memory population.
A Pivotal Role for CD40-Mediated IL-6 Production by Dendritic Cells during IL-17 Induction In Vivo
Authors: Perona-Wright Georgia , Jenkins Stephen J. , O'Connor Richard A. , Zienkiewicz Dimitrios , McSorley Henry J. , Maizels Rick M. , Anderton Stephen M. , MacDonald Andrew S.
Published: February 2009

The costimulatory requirements for Th17 development remain to be defined. In this study, we show that CD40-deficient animals immunized with the Gram-positive bacterium Propionibacterium acnes were specifically impaired in their ability to mount an IL-17 response, but not that of IFN-γ. The same cytokine imbalance resulted from in vivo priming with pathogen-pulsed, CD40-deficient dendritic cells (DC). Engagement of CD40 on P. acnes-conditioned DC stimulated the release of IL-12, IL-23, and IL-6, of which IL-6 alone proved essential for Th17 differentiation. Compared with wild-type DC, priming with those lacking expression of CD40 resulted in reduced disease severity during experimental autoimmune encephalomyelitis, coincident with reduced IL-17 production. Our data delineate sequential requirements for DC expression of CD40 and production of IL-6 during Th17 polarization in vitro and in vivo, and reveal distinct costimulatory requirements for Th1 vs Th17 generation.
Synthesis and Structure–Property Correlation in Shape‐Controlled ZnO Nanoparticles Prepared by Chemical Vapor Synthesis and their Application in Dye‐Sensitized Solar Cells
Authors: Bacsa Revathi R. , Dexpert‐Ghys Jeannette , Verelst Marc , Falqui Andrea , Machado Bruno , Bacsa Wolfgang S. , Chen Peter , Zakeeruddin Shaik M. , Graetzel Michael , Serp Philippe
Published: February 2009

Here, the large scale synthesis of nanocrystalline ZnO spheres and tetrapods in the size range of 8–40 nm by chemical vapor synthesis using zinc metal as precursor is described. A detailed study of the effect of experimental parameters on the morphology and yield is presented. High‐resolution transmission electron microscopy images of the tetrapods show that they are formed by the self assembly of four nanorods in the vapor phase. The tetrapods have optical absorption coefficients that are one order of magnitude greater than the spheres and show intense UV luminescence whereas the spheres show only the green emission. The observed differences in the optical properties are related to the presence of surface defects present in the nanospheres. The tetrapods have increased efficiencies for application in dye sensitized solar cells when compared to spheres.
A C1 microkinetic model for methane conversion to syngas on Rh/Al2O3
Authors: Maestri Matteo , Vlachos Dionisios G. , Beretta Alessandra , Groppi Gianpiero , Tronconi Enrico
Published: February 2009

A microkinetic model capable of describing multiple processes related to the conversion of natural gas to syngas and hydrogen on Rh is derived. The parameters of microkinetic models are subject to (intrinsic) uncertainty arising from estimation. It is shown that intrinsic uncertainty could markedly affect even qualitative model predictions (e.g., the rate‐determining step). In order to render kinetic models predictive, we propose a hierarchical, data‐driven methodology, where microkinetic model analysis is combined with a comprehensive, kinetically relevant set of nearly isothermal experimental data. The new, thermodynamically consistent model is capable of predicting several processes, including methane steam and dry reforming, catalytic partial oxidation, H2 and CO rich combustion, water‐gas shift and its reverse at different temperatures, space velocities, compositions and reactant dilutions, using the measured Rh dispersion as an input. Comparison with other microkinetic models is undertaken. Finally, an uncertainty analysis assesses the effect of intrinsic uncertainty and catalyst heterogeneity on the overall model predictions. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Feedback control of dissipative PDE systems using adaptive model reduction
Authors: Varshney Amit , Pitchaiah Sivakumar , Armaou Antonios
Published: February 2009

The problem of feedback control of spatially distributed processes described by highly dissipative partial differential equations (PDEs) is considered. Typically, this problem is addressed through model reduction, where finite dimensional approximations to the original infinite dimensional PDE system are derived and used for controller design. The key step in this approach is the computation of basis functions that are subsequently utilized to obtain finite dimensional ordinary differential equation (ODE) models using the method of weighted residuals. A common approach to this task is the Karhunen‐Loève expansion combined with the method of snapshots. To circumvent the issue of a priori availability of a sufficiently large ensemble of PDE solution data, the focus is on the recursive computation of eigenfunctions as additional data from the process becomes available. Initially, an ensemble of eigenfunctions is constructed based on a relatively small number of snapshots, and the covariance matrix is computed. The dominant eigenspace of this matrix is then utilized to compute the empirical eigenfunctions required for model reduction. This dominant eigenspace is recomputed with the addition of each snapshot with possible increase or decrease in its dimensionality; due to its small dimensionality the computational burden is relatively small. The proposed approach is applied to representative examples of dissipative PDEs, with both linear and nonlinear spatial differential operators, to demonstrate its effectiveness of the proposed methodology. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Approximate dynamic programming based optimal control applied to an integrated plant with a reactor and a distillation column with recycle
Authors: Tosukhowong Thidarat , Lee Jay H.
Published: February 2009

An approximate dynamic programming (ADP) method has shown good performance in solving optimal control problems in many small‐scale process control applications. The offline computational procedure of ADP constructs an approximation of the optimal “cost‐to‐go” function, which parameterizes the optimal control policy with respect to the state variable. With the approximate “cost‐to‐go” function computed, a multistage optimization problem that needs to be solved online at every sample time can be reduced to a single‐stage optimization, thereby significantly lessening the real‐time computational load. Moreover, stochastic uncertainties can be addressed relatively easily within this framework. Nonetheless, the existing ADP method requires excessive offline computation when applied to a high‐dimensional system. A case study of a reactor and a distillation column with recycle was used to illustrate this issue. Then, several ways were proposed to reduce the computational load so that the ADP method can be applied to high‐dimensional integrated plants. The results showed that the approach is much more superior to NMPC in both deterministic and stochastic cases. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Noninvasive collection of fresh hairs from free‐ranging howler monkeys for DNA extraction
Authors: Améndola‐Pimenta Monica , García‐Feria Luis , Serio‐Silva Juan Carlos , Rico‐Gray Victor
Published: February 2009

The use of noninvasive collected samples as source of DNA in studies of wild primate populations has increased in recent years. Fresh‐plucked hairs represent an important source of DNA, with relatively high quality and concentration. In this study, we describe a low‐cost noninvasive technique for collecting fresh‐plucked hairs used to obtain DNA samples from free‐ranging black howler monkey populations (Alouatta pigra). We designed and manufactured darts made of wooden dowels, with the anterior part smeared with glue, which were projected with blowpipes to trap howler monkey hairs. All of the materials to make the darts are inexpensive and are available locally. We collected 89 samples from 76 individuals residing in 15 troops, and the total number of hairs obtained was 754. We found no differences in the number of hairs collected among sex–age classes or among localities but the percentage of darts recovered with sample varied among localities. Preliminary results indicate that over 96% of samples yielded DNA suitable for polymerase chain reaction‐based microsatellite marker analysis. The technique proved successful for collecting fresh‐plucked hairs of free‐ranging black howler monkeys without any trauma to the animals and can be easily adapted to obtain samples from other wild primate and mammal species. Am. J. Primatol. 71:359–363, 2009. © 2009 Wiley‐Liss, Inc.
Selective neuronal nitric oxide synthase inhibitors and the prevention of cerebral palsy
Authors: Ji Haitao , Tan Sidhartha , Igarashi Jotaro , Li Huiying , Derrick Matthew , Martásek Pavel , Roman Linda J. , Vásquez‐Vivar Jeannette , Poulos Thomas L. , Silverman Richard B.
Published: February 2009

Objective

To design a new class of selective neuronal nitric oxide synthase (NOS) inhibitors, and demonstrate that administration in a rabbit model for cerebral palsy (CP) prevents hypoxia‐ischemia–induced deaths and reduces the number of newborn kits exhibiting signs of CP.

Methods

We used a novel computer‐based drug design method called fragment hopping to identify new chemical entities, synthesized them, and conducted in vitro enzyme inhibition studies with the three isozymes of NOS and in vivo experiments to monitor cardiovascular effects on pregnant rabbit dams, NOS activity, and NOx (NO and NO2) concentration in fetal brain, and assess neurobehavioral effects on kits born to saline‐ and compound treated dams.

Results

The computer‐based design led to the development of powerful and highly selective compounds for inhibition of neuronal NOS over the other isozymes. After maternal administration in a rabbit model of CP, these compounds were found to distribute to fetal brain, to be nontoxic, without cardiovascular effects, inhibit fetal brain NOS activity in vivo, reduce NO concentration in fetal brain, and dramatically ameliorate deaths and number of newborn kits exhibiting signs of CP.

Interpretation

This approach may lead to new preventive strategies for CP. Ann Neurol 2008
Dynamics of 1,3‐Dipolar Cycloaddition Reactions of Diazonium Betaines to Acetylene and Ethylene: Bending Vibrations Facilitate Reaction
Authors: Xu Lai , Doubleday Charles E. , Houk K. N.
Published: February 2009

Getting the bends: The dynamics of 1,3‐dipolar cycloaddition reactions have been explored by decomposing transition vector, quasi‐classical trajectories, and single trajectories. Dipole bending (see picture) makes the largest contribution to the TS distortion energy and constitutes the major part of transition‐state distortion energy in the favored concerted pathway.

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Synthesis of Single‐Crystal Tetra(4‐pyridyl)porphyrin Rectangular Nanotubes in the Vapor Phase
Authors: Yoon Seok Min , Hwang In‐Chul , Kim Kwang S. , Choi Hee Cheul
Published: February 2009

Stacking up: One‐dimensional single‐crystalline rectangular nanotubes (RNTs) of 5,10,15,20‐tetra(4‐pyridyl)porphyrin (H2TPyP, see picture) are synthesized by a vaporization–condensation–recrystallization process. The single‐crystal X‐ray diffraction and selected‐area electron diffraction data reveal that the H2TPyP RNTs form by self‐stacking of H2TPyP units through hydrogen‐bonding, H–π, and π–π intermolecular interactions.

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Membrane reformer PEM cogeneration systems for residential applications–Part A: full load and partial load simulation
Authors: Campanari Stefano , Macchi Ennio , Manzolini Giampaolo
Published: February 2009

This two‐part paper investigates the performances and economic potential benefits of a fuel cell cogeneration system based on a membrane reformer (MREF), using polymer electrolyte membrane (PEM) fuel cells, applied to residential cogeneration. Part A of this work focuses on the thermodynamic analysis and simulation of the system at full and partial load conditions, discussing its performance by means of a sensitivity analysis carried out under different operating conditions. Part B presents the technoeconomic analysis of the proposed system integrated into a real residential application, dealing with the energy savings and the economic balances, and proposes a preliminary design of the cogeneration unit.

The system is based upon a PEM fuel cell, integrated with a membrane reformer (MREF) to form a small‐scale, highly efficient cogeneration unit, potentially suitable for application to distributed generation in the residential field. The high purity hydrogen fuel required by the PEM fuel cell is produced in the membrane reformer through hydrogen selective membranes based on a Pd‐Ag alloy. The analysis is carried out aiming to define the system energy balances in all the conditions occurring under real operation, including the influence of ambient temperature and of the expected fuel cell efficiency decay with time. The discussion reveals the relevant potential advantages of the MREF solution with respect to fuel cell units based on steam reforming (SR) or auto‐thermal reforming (ATR): when compared to these solutions, MREF exhibits a 10% points higher electrical efficiency and requires a much simpler plant layout. These results are the basis for the detailed system technoeconomic analysis carried out in Part B of the work. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Membrane reformer PEM cogeneration systems for residential applications—Part B: techno‐economic analysis and system layout
Authors: Campanari Stefano , Macchi Ennio , Manzolini Giampaolo
Published: February 2009

This two‐part paper investigates the performances and potential economic benefits of a membrane reformer (MREF)‐based fuel cell cogeneration system, using polymer electrolyte membrane (PEM) fuel cells, applied to residential cogeneration. Part A of the work focuses on the thermodynamic analysis and simulation of the system at full and partial load conditions, discussing its performance by means of a sensitivity analysis carried out under different operating conditions. Part B presents the techno‐economic analysis of the proposed system integrated into a real residential application, dealing with the energy savings and the economic balances, and proposes a preliminary design of the cogeneration unit.

The higher electric efficiency of the innovative MREF system proposed in this work allows a yearly cost savings about 50% higher than cost savings allowed by fuel cell cogeneration units based on conventional fuel processors. Moreover, CO2 emissions savings, calculated for an average northern Italy single‐family load, is about 1.6 tCO2/year.

The paper also presents a proposed system layout, discussing the preliminary design of all the required components and analyzing with particular care the issues related to the heat recovery loop and to the arrangement of the system key component: the membrane reforming reactor. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
The role of trust belief and its antecedents in a community‐driven knowledge environment
Authors: Kim Byoungsoo , Han Ingoo
Published: February 2009

Given the prevalence of community‐driven knowledge sites (CKSs), such as Naver Knowledge In and Yahoo! Answers, it has become important to understand the key drivers of user decision‐making processes. In the online environment, building and maintaining user trust belief is a significant challenge to the continuing growth and long‐term viability of information systems (IS), due to the open nature of the Internet. This study develops a theoretical framework to examine the role of trust belief in the CKS post‐adoption phenomenon. This study also presents an investigation of the key antecedents of trust belief to understand the mechanism of building user trust belief in a CKS. Based on the multidimensional trust formation model, this study posits user satisfaction, perceived reputation, disposition to trust, and information quality as the trust belief antecedents. Data collected from 258 users who have direct experiences with Naver Knowledge In was used to test the research model using structural equation modeling. This study preliminarily confirms the salience of user trust belief in the CKS post‐adoption phenomenon. The findings also indicate that the cognitive‐based, affective‐based, and personality‐oriented trust antecedents play a significant role in enhancing trust belief in a CKS. Theoretical and practical implications of the findings are described.
Collective indexing of emotions in images. A study in emotional information retrieval
Authors: Schmidt Stefanie , Stock Wolfgang G.
Published: February 2009

Some documents provoke emotions in people viewing them. Will it be possible to describe emotions consistently and use this information in retrieval systems? We tested collective (statistically aggregated) emotion indexing using images as examples. Considering psychological results, basic emotions areanger,disgust,fear,happiness, andsadness. This study follows an approach developed by Lee and Neal (2007) for music emotion retrieval and applies scroll bars for tagging basic emotions and their intensities. A sample comprising 763 persons tagged emotions caused by images (retrieved fromwww.Flickr.com) applying scroll bars and (linguistic) tags. Using SPSS, we performed descriptive statistics and correlation analysis. For more than half of the images, the test persons have clear emotion favorites. There are prototypical images for given emotions. The document‐specific consistency of tagging using a scroll bar is, for some images, very high. Most of the (most commonly used) linguistic tags are on the basic level (in the sense of Rosch's basic level theory). The distributions of the linguistic tags in our examples follow an inverse power‐law. Hence, it seems possible to apply collective image emotion tagging to image information systems and to present a new search option for basic emotions. This article is one of the first steps in the research area of emotional information retrieval (EmIR).
Connecting visual cues to semantic judgments in the context of the office environment
Authors: Bondarenko Olha , Janssen Ruud
Published: February 2009

In this article, we present the results of a study that systematically explored “externalized knowledge” in the context of office work. The aim of the study was to investigate what knowledge information workers externalize into their physical environment (e.g., when shuffling or relocating paper documents on their desks) and how this knowledge is “encoded” in visual cues. Based on field data, categories of visual cues and semantic judgments were derived, a way to aggregate these categories into clusters was proposed, and a model of the relationships among cues and judgments was developed. We conclude that visual cues of physical documents represent, besides their content, information about the features of content and about different aspects of task context and overview. Three clusters outline the space of visual cues: (a) content that resides in (b) a holder that is (c) located somewhere in space. The three identified clusters of semantic judgments express three aggregation levels of one's work: (a) individual document, (b) the context of this document, and (c) an overview over someone's activities. The nature of the relationships among these clusters is reviewed through three aspects: content‐dependence, flexibility, and effort. We conclude with implications of the results and future research directions.
Generalizations of Egghe's g‐index
Authors: Woeginger Gerhard J.
Published: February 2009

This paper introduces the generalized Egghe‐indices as a new family of scientific impact measures for ranking the output of scientific researchers. The definition of this family is strongly inspired by Egghe's well‐known g‐index. The main contribution of the paper is a family of axiomatic characterizations that characterize every generalized Egghe‐index in terms of four axioms.
Metallic Impurities within Residual Catalyst Metallic Nanoparticles Are in Some Cases Responsible for “Electrocatalytic” Effect of Carbon Nanotubes
Authors: Pumera Martin , Iwai Hideo
Published: February 2009

It′s what′s on the inside that counts: In some cases, the metallic impurities within residual catalyst metallic nanoparticle impurities, which remain in carbon nanotubes even after their purification, are responsible for the “electrocatalytic” properties of carbon nanotubes. This is demonstrated by using double‐walled carbon nanotubes (DWCNTs) containing cobalt residual catalyst nanoparticle impurities, which themselves contain iron‐based impurities.

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We show that in some cases, the metallic impurities within residual catalyst metallic nanoparticle impurities, which remain in carbon nanotubes from their synthesis even after purification, are responsible for “electrocatalytic” properties of carbon nanotubes. This is demonstrated in an example of double‐walled carbon nanotubes (DWCNTs) containing cobalt residual catalyst nanoparticle impurities, which themselves contain iron‐based impurities. It was found that iron‐based impurities within Co residual nanoparticles present in DWCNTs are responsible for the electrochemical reduction of hydrogen peroxide. The chemical states of metallic impurities were investigated by high‐resolution X‐ray photoelectron spectroscopy.
Chemical and Pharmacological Studies of the Plants from Genus Celastrus
Authors: Su Xiao‐Hui , Zhang Man‐Li , Zhan Wen‐Hong , Huo Chang‐Hong , Shi Qing‐Wen , Gu Yu‐Cheng , Kiyota Hiromasa
Published: February 2009

The plants of genus Celastrus, distributed in Asia, have been used as natural insecticides and folk medicines to treat fever, chill, joint pain, edema, rheumatoid arthritis, and bacterial infection in China for a long time. This contribution reviews the chemical constituents, 1–144, isolated from the plants in genus Celastrus in the past few decades, and their biological activities. The compounds listed are sesquiterpenes (β‐agarofurans), diterpenes, triterpenes, alkaloids, and flavonoids.
Astilbotriterpenic Acid Induces Growth Arrest and Apoptosis in HeLa Cells through Mitochondria‐Related Pathways and Reactive Oxygen Species (ROS) Production
Authors: Zhang Yi‐Bin , Ye Yi‐Ping , Wu Xiao‐Dan , Sun Hong‐Xiang
Published: February 2009

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Astilbotriterpenic acid (1), a novel ursane‐type triterpenoid from the rhizomes of Astilbe chinensis, has cytostatic properties in several cancer cell lines and induces apoptosis in HeLa cell. The aim of this study was to investigate the mechanisms by which such properties are exerted, with special reference to the anti‐proliferative and apoptotic potential on HeLa cells. Compound 1 showed a marked concentration‐ and time‐dependent inhibition of HeLa cell proliferation, and induced G0/G1 phase arrest of HeLa cell in a dose‐dependent manner. There was a quick attenuation of mitochondrial membrane potential (Δψm) with the alterations of Bcl‐2/Bax mRNA express value in 1‐treated HeLa, indicating the participation of a mitochondria‐related mechanism. Pretreatment of a pan‐caspase inhibitor (benzyloxycarbonyl)‐Val‐Ala‐Asp‐(fluoromethyl) ketone (z‐VAD‐fmk) significantly increases the viability of 1‐treated HeLa cells implied that the participation of caspase; Western‐blot analysis showed the activation of initiator caspase‐8 and caspase‐9, and executor caspase‐3. Meanwhile, treatment with 1 stimulates the generation of reactive oxygen species (ROS) in HeLa cell. Taken together, our data showed that compound 1 induced growth arrest and apoptosis in HeLa cells through mitochondria‐related pathways and ROS production, and may be further evaluated as a chemotherapeutic agent for human cancer.
Variability for Free Sugars and Organic Acids in Capsicum chinense
Authors: Jarret Robert L. , Berke Terry , Baldwin Elizabeth A. , Antonious George F.
Published: February 2009

Variability in the concentrations of the chemical constituents that contribute to fruit flavor in Capsicum chinense is poorly documented in the scientific literature. We surveyed fruit of 216 landraces and cultivated varieties of Capsicum chinense acquired from North, Central, and South America, and analyzed these for concentrations of the simple sugars sucrose, glucose, and fructose, and citric, malic, succinic, fumaric, and ascorbic acids. Concentrations (mg/100 g Fresh Weight (FW) of whole fruit) of sucrose, glucose, and fructose in fruit of this species ranged from 0.0 to 150, 68 to 701, and 101 to 823, respectively. The total of these sugars (sucrose+glucose+fructose) ranged from 198 to 1543 mg/100 g FW. Concentrations of organic acids ranged from 0.0 (not detected) to 818, 430, 340, and 232 mg/100 g FW for citric, malic, fumaric, and succinic acids, respectively. However, the relative ranking in the concentrations of the individual acids was genotype‐dependent. Total ascorbic‐acid values ranged from 30 to 1466 mg/100 g FW. These data serve to document the range in the concentrations of individual sugars and acids present in mature C. chinense fruit and suggest that this variability may lend itself to studies involving the synthesis and/or metabolism of compounds associated with fruit flavor.
Anthraquinones from Natural and Transformed Roots of Plocama pendula
Authors: Fraga Braulio M. , Quintana Nayra , Díaz Carmen E.
Published: February 2009

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Five new and 15 known anthraquinones have been isolated from Plocama pendula root cultures transformed by Agrobacterium rhizogenes. The new anthraquinones were named balonone (1), balonone methyl ether (2), and plocamanones A, B, and C (3–5, resp.). Moreover, lucidin dimethyl ether (18) was obtained for the first time as a natural compound. On the other hand, a study of P. pendula natural roots afforded another two new anthraquinones, i.e., plocamanone D (6) and chionone (8). The anthraquinone isozyganein dimethyl ether (35) has been isolated for the first time from nature. Another 19 known anthraquinones were also obtained from the natural roots.
New Analogues of Epiboxidine Incorporating the 4,5‐Dihydroisoxazole Nucleus: Synthesis, Binding Affinity at Neuronal Nicotinic Acetylcholine Receptors, and Molecular Modeling Investigations
Authors: Dallanoce Clelia , Magrone Pietro , Bazza Paola , Grazioso Giovanni , Rizzi Luca , Riganti Loredana , Gotti Cecilia , Clementi Francesco , Frydenvang Karla , De Amici Marco
Published: February 2009

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A group of novel 4,5‐dihydro‐3‐methylisoxazolyl derivatives, structurally related to epiboxidine (=(1R,4S,6S)‐6‐(3‐methylisoxazol‐5‐yl)‐7‐azabicyclo[2.2.1]heptane), was preparedvia1,3‐dipolar cycloaddition of acetonitrile oxide to different olefins. Target compounds1aand1b, 2aand2b, 3, 4, and5were tested for affinity at neuronal nicotinic heteromeric (α4β2) and homomeric (α7) acetylcholine receptors. Notably, diastereoisomers1aand1bwere characterized by a massive drop of the affinity at theα4β2 subtypes (Kivalues spanning the range 4.3–126 μM), when compared with that of epiboxidine (Ki=0.6 nM). Therefore, the replacement of the 3‐methylisoxazole ring of epiboxidine with the 4,5‐dihydro‐3‐methylisoxazole nucleus is detrimental for the affinity atα4β2 receptors. A comparable lack of affinity/selectivity for the two nAChR subtypes under study was evidenced for the remaining epiboxidine‐related dihydroisoxazole derivatives2aand2b, and3–5. Diastereoisomers1aand1b, and spirocyclic derivative3were docked into molecular models of the receptor subtypes under study, and their binding mode was compared with that of reference ligands endowed with high binding affinity.
Kaempferol Glycosides from Lobularia maritima and Their Potential Role in Plant Interactions
Authors: Fiorentino Antonio , Ricci Andreina , D'Abrosca Brigida , Golino Annunziata , Izzo Angelina , Pascarella Maria Teresa , Piccolella Simona , Esposito Assunta
Published: February 2009

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Six kaempferol glycosides, four of them characterized for the first time, were isolated from the leaf extract of Lobularia maritima. The structural elucidation was performed by a combined approach using Electrospray‐Ionization Triple‐Quadrupole Mass‐Spectrometric (ESI/TQ/MS) techniques, and 1D‐ and 2D‐NMR experiments (1H, 13C, DEPT, DQ‐COSY, TOCSY, ROESY, NOESY, HSQC, HMBC, and HSQC‐TOCSY). The isolated kaempferol derivatives have different disaccharide substituents at C(3) and four of them have a rhamnose unit at C(7). To evaluate their potential allelopathic role within the herbaceous plant community, the compounds, as well as the aglycone obtained from enzymatic hydrolysis, have been tested in vitro on three coexisting plant species, Dactylis hispanica, Petrorhagia velutina, and Phleum subulatum. The results obtained allow us to hypothesize that the type of the sugar modulates the biological response. The bioassay data, analyzed by a multivariate approach, and grouping the compounds on the basis of the number of sugar units and the nature of carbohydrates present in the disaccharide moiety, indicate a structure–activity relationship.
Balticols A–F, New Naphthalenone Derivatives with Antiviral Activity, from an Ascomycetous Fungus
Authors: Shushni Muftah A. M. , Mentel Renate , Lindequist Ulrike , Jansen Rolf
Published: February 2009

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Six new naphthalenone derivatives, balticols A–F (1–6, resp.) and the known metabolite altechromone A (8) were isolated from the AcOEt extract of the culture broth of fungal strain 222 belonging to the Ascomycota, which was found on driftwood collected at the coast of the Greifswalder Bodden, Baltic Sea, Germany. All structures were elucidated on the basis of NMR spectroscopic data and mass spectrometric analyses. The balticols were found to exhibit inhibitory activity against influenza virus A and herpes simplex virus. The most potent antiviral activity was observed for balticol E (5) with an IC50 value of 0.01 μg/ml against Herpes simplex virus type I.
Synthesis and Hybridization Properties of Modified Oligodeoxynucleotides Carrying Non‐Natural Bases
Authors: Aviñó Anna , Pérez‐Rentero Sónia , Garibotti Alejandra V. , Siddiqui Maqbool A. , Márquez Victor E. , Eritja Ramon
Published: February 2009

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The impact of the presence of nonnatural bases on the properties of oligodeoxynucleotides has been studied. First, oligodeoxynucleotides carrying 2′‐deoxyzebularine were prepared, and the stability of duplexes carrying this analogue was determined by DNA melting experiments. Melting temperatures and thermodynamic data indicated the preference of 2′‐deoxyzebularine for 2′‐deoxyguanosine, which behaves as a 2′‐deoxycytidine analogue, forming a less stable base pair due to the absence of the amino group at position 4. Moreover, the duplex–hairpin equilibrium of a self‐complementary oligodeoxynucleotide carrying several natural and nonnatural bases including 2′‐deoxyzebularine as a central mispair, was studied. Depending on the base present in the middle of the sequence, it is possible to affect the stability of the bimolecular duplex modulating the duplex–hairpin equilibrium. Magnesium ions were shown to stabilize preferentially the bimolecular duplex form. The results indicate the importance of the modifications and the role of cations in shifting the structural equilibrium.
Transcatheter closure of long tubular patent arterial ducts: The Amplatzer Duct Occluder II—A new and valuable tool
Authors: Morgan Gareth , Tometzki Andrew J. , Martin Robin P.
Published: February 2009

Despite the wide variety of occlusion devices available for closing the patent ductus arteriosus; some defects with unusual morphology still remain a challenge. The drive for increasingly user friendly and lower caliber delivery systems is also ongoing. The new amplatzer ductal occluder II may prove to be a useful additional tool in these circumstances. We describe our initial experiences with this new device in three patients with long tubular (Type C) ducts. © 2009 Wiley‐Liss, Inc.
Long‐term outcome after balloon angioplasty of coarctation of the aorta in adolescents and adults: Is aneurysm formation an issue?
Authors: Walhout R.J. , Suttorp M.J. , Mackaij G.J. , Ernst J.M.P.G. , Plokker H.W.M.
Published: February 2009

Objectives:The purpose was to evaluate long‐term outcome following balloon angioplasty for coarctation in adults.Background:Long‐term results of balloon angioplasty for native coarctation in adults remain incomplete, especially concerning the occurrence of aneurysm formation.Methods:Long‐term follow‐up data were collected in consecutive patients retrospectively. Results of balloon angioplasty (29 patients, age 15–71 years, during 1995–2005) for discrete, native coarctation were evaluated, including MRI or CT.Results:Mean follow‐up ranged from 2.2 to 13 years (mean 8.5 ± 3.2). Immediate success was obtained in all patients. Early mortality or complications were not encountered. Peak systolic pressure gradient decreased from 52 ± 21 to 7.2 ± 7.6 mm Hg (P< 0.001). Intima tear was detected in eight procedures angiographically, without signs of dissection. Three‐month follow‐up angiography in these patients showed unchanged (4/8 patients) or diminished abnormalities (4/8 patients). One asymptomatic patient, known with left ventricular dysfunction due to significant aortic valve insufficiency, died suddenly 5 years after balloon angioplasty. Recoarctation occurred in one patient (3%). Late aneurysm formation was excluded by MR in 24/29 and CT in remaining 5/29 patients during follow‐up, including those patients in whom intima tear was encountered immediately postangioplasty. In three of seven patients an irregular aortic contour persisted, without indication of progression or aneurysm formation. Hypertension was completely relieved in 67% (14/21 patients) and improved in 33% (7/21 patients).Conclusions:Balloon angioplasty for native coarctation yields low reintervention probability in adult patients. Despite occurrence of angiographically established intimal tearing, aortic dissection and aneurysm formation were not encountered. © 2009 Wiley‐Liss, Inc.
CBT and hypnosis: the worry‐bug versus the cake
Authors: Kuttner Leora
Published: February 2009

Sleep and pain negatively impact each other. Children in pain often have difficulty going to sleep and sustaining sleep. Anxiety often develops within this negative cycle. Hypnotherapy has been noted as an effective intervention for pain, sleep and anxiety. The case presented illustrates the use of hypnotherapy in contrast to cognitive behavioural therapy (CBT) to resolve an 11‐year‐old girl's cycle of persistent anxiety, abdominal pain and sleep interruption. Utilizing the child's favourite activity of baking a cake, a metaphor for successful sleep was developed. The hypnotherapeutic use of surprise and dissonance promoted a rapid resolution of this pre‐teen's difficulties. An explication of this process is provided. Copyright © 2009 British Society of Experimental & Clinical Hypnosis. Published by John Wiley & Sons, Ltd.