bluuebunny/crossref_metadata_2025_split huggingface dataset:
Connecting visual cues to semantic judgments in the context of the office environment
Authors: Bondarenko Olha , Janssen Ruud 
Published: February 2009

AbstractIn 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

AbstractThis 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

AbstractIt′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.magnified imageWe 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

AbstractThe 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

Abstractmagnified imageAstilbotriterpenic 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

AbstractVariability 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

Abstractmagnified imageFive 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

Abstractmagnified imageA 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

Abstractmagnified imageSix 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

Abstractmagnified imageSix 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

Abstractmagnified imageThe 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

AbstractDespite 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

AbstractObjectives: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

AbstractSleep 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.
A Fast‐Moving Copper‐Based Molecular Shuttle: Synthesis and Dynamic Properties
Authors: Durola Fabien , Lux Jacques , Sauvage Jean‐Pierre 
Published: February 2009

AbstractFast‐track changes: The synthesis of a new copper‐based molecular shuttle is described, with a coordinating macrocycle based on a nonhindering but endocyclic ligand (see scheme), which makes the ligand exchange easier, and thus the motions of the ring along the thread faster.magnified imageThe present report deals with the synthesis of a two‐station [2]rotaxane consisting of a dpbiiq‐incorporating macrocycle (dpbiiq: 8,8′‐diphenyl‐3,3′‐biisoquinoline) threaded by a coordinating fragment whose complexing units are a dpp and a terpy ligand (dpp: 2,9‐diphenyl‐1,10‐phenanthroline; terpy: 2,2′,6′,2”‐terpyridine). The [2]rotaxane was prepared in 11 steps from commercially available or easy‐to‐make molecules, without taking into account the preparation of the dpbiiq‐containing 39‐membered ring, which was available in our group. The ring‐incorporated bidentate chelate is at the same time endocyclic and sterically nonhindering, which is a specific property of the dpbiiq‐coordinating unit. This unique feature has a profound influence on the rate of the ring‐and‐copper translation motion between the two stations of the axle. Based on an analogous multistep strategy, a related molecular shuttle has also been prepared that contains exactly the same axle and stoppers as the first compound but whose threaded ring incorporates the sterically hindering dpp chelate. The translation motions of this other system are several orders of magnitude slower than the corresponding movements of the dpbiiq‐based compound. The motion corresponding to the rearrangement of the unstable five‐coordinate copper(I) form of the compounds is relatively fast for both shuttles; the half lifetime of the five‐coordinate CuIspecies being below 20 ms for the dpbiiq‐containing system and below 1 s for the dpp‐based molecule. The reverse motion corresponding to the rearrangement of the four‐coordinate copper(II) complexes is much slower, especially for the dpp‐based system. It is of the order of several hours for the dpp‐based shuttle and only one second or less for the dpbiiq system, under exactly the same conditions. The remarkable difference between the motion rates for the two two‐station shuttles demonstrates that the use of a very open chelate such as dpbiiq is extremely beneficial in the context of fast‐moving molecular machines.
Self‐Assembly of a Trinuclear Luminescent Europium Complex
Authors: Zebret Soumaila , Dupont Nathalie , Bernardinelli Gérald , Hamacek Josef 
Published: February 2009

AbstractTriangular luminescent box: Self‐assembly of a new multidentate receptor with europium cations results in the formation of trinuclear discrete complexes. X‐ray crystallography shows that nine‐coordinate cations are linked by ligands to provide a triangular complex in the solid state and in solution. Despite the coordinated solvent molecules, this topologically unusual complex exhibits remarkable luminescent properties.magnified image
Hydrazinoanthrylboronic acids as exciton‐coupled circular dichroism (ECCD) probes for multivalent catechols, particularly epigallocatechin gallate
Authors: Hennig Andreas , Hagihara Shinya , Matile Stefan 
Published: February 2009

AbstractWe report the use of exciton‐coupled circular dichroism (ECCD) spectroscopy in multianalyte sensing systems in complex matrices. To prepare ECCD sensors, anionic anthrylhydazides are reacted with formylphenylboronic acids to give hydrazinoanthrylboronic acids that in turn are reacted with multivalent catechols in aqueous solution. The ECCD signal between the anthracene chromophores in the resulting boronate ester products depends strongly on the structure of the boronic acid sensor and the polyphenol analyte. This dependence of the ECCD signal on analyte structure is interesting for sensing applications. Best ECCD response is found for epigallocatechin gallate (EGCG), a key polyphenol in green tea. Weakly bell‐shaped pH profiles, sensitivity to ionic strength and decreasing ECCD with decreasing solvent polarity imply that the CD active product is stabilized by hydrophobic interactions between the anthracene chromophores and by formation of the conjugate bases of the boronic esters. Analyte screening reveals selectivity for divalent catechols, with effective concentrations down to EC50 = 5 μM for EGCG. Monovalent or achiral catechols such as (+)‐catechin, protocatechuate or homoprotocatechuate are not detected. However, the latter two become detectable when attached to a chiral, divalent 1,2‐cyclohexylamine scaffold. Application of this simple, user‐friendly ECCD system to polyphenol sensing in various green tea extracts delivers easily accessible and reproducible values in the expected range. Chirality, 2009. © 2009 Wiley‐Liss, Inc.
Compaction of cell shape occurs before decrease of elasticity in CHO‐K1 cells treated with actin cytoskeleton disrupting drug cytochalasin D
Authors: Schulze Christian , Müller Karla , Käs Josef A. , Gerdelmann Jens C. 
Published: February 2009

AbstractThe actin filaments of the cytoskeleton form a highly dynamic polymer scaffold which is actively involved in many essential mechanisms such as cell migration, transport, mitosis, and mechanosensitivity. We treated CHO‐K1 cells with different concentrations of the actin cytoskeleton disrupting drug cytochalasin D. Then investigating the cells' elastic behaviour by scanning force microscopy‐based rheology we confirmed for high cytochalasin D concentrations (≥1.5 μM) a significant decrease of mechanical stability. At lower concentrations we measured no significant softening, but flattening and a horizontal contraction was observable even at low concentrations (≥0.3 μM) of cytochalasin D. The observed changes in cell shape resulted in a lower cell volume, showing that there is compensation by volume for small decreases in cytoskeletal strength resulting from reduced numbers or lengths of actin filaments. These results suggest that the characteristic functions defining a cell's mechanical stability such as mechanosensitivity can be maintained via small changes in cell volume in order to counter fluctuations in cytoskeletal composition. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.