bluuebunny/crossref_metadata_2025 huggingface dataset:
Individual variation in nest size and nest site features of the Bornean orangutans (Pongo pygmaeus)
Authors: Rayadin Yaya , Saitoh Takashi
Published: February 2009

Nest construction is a daily habit of independent orangutans for sleeping or resting. Data on their nests have been used in various ecological studies (e.g., density estimation, ranging behavior, evolution of material culture) because they are the most observable field signs. We investigated nest size and nest site features of Bornean orangutans in the wild during 10 months' fieldwork at three sites in East Kalimantan, Indonesia: Kutai National Park, Birawa, and Meratus. To examine individual variation, we followed 31 individual orangutans and recorded the 92 nests they made for nest size (diameter) and nest site features (height of nest above ground, tree species used for the nest site, the diameter and height of the tree, whether the nest was new or reused, and nest location within the tree). Analyses taking age–sex classes of the focal individuals into consideration showed significant age–sex differences in nest size and location, but not in nest height or nest tree features (diameter, height of tree, and height of lowest branch). Mature orangutans (adult females, unflanged and flanged males) made larger nests than immatures (juveniles and adolescents). Flanged male orangutans with larger nests used stable locations for nesting sites and reused old nests more frequently than immatures. The overall proportion of nests in open (exposed) locations was higher than in closed (sheltered) locations. Flanged males and immatures frequently made open nests, whereas adult females with an infant preferred closed locations. The good correspondence between nest size and age–sex classes indicates that nest size variation may reflect body size and therefore age–sex variation in the population. Am. J. Primatol. 71:393–399, 2009. © 2009 Wiley‐Liss, Inc.
Post‐conflict third‐party affiliation in chimpanzees: what's in it for the third party?
Authors: Koski Sonja E. , Sterck Elisabeth H. M.
Published: February 2009

Affiliative behavior after conflicts between conflict participants and other group members is common in many primate species. The proposed functions for such triadic interactions are numerous, mostly concerning the benefit for the former conflict opponents. We investigated post‐conflict third‐party affiliation (TPA) in captive chimpanzees (Pan troglodytes) with the aim of assessing what the affiliating third parties may gain from affiliation. Specifically, we tested whether third‐party‐initiated affiliation protects the third parties from further aggression by conflict opponents. We found support for this “self‐protection hypothesis,” in that third parties selectively directed affiliation to those opponents who more often gave further aggression to them, and affiliation effectively decreased their chance of receiving aggression from these opponents. However, a subset of affiliation, provided to conflict victims by their own kin, appeared to not be self‐protective and the function of it remained open. We conclude that chimpanzee third‐party‐initiated affiliation is a more heterogeneous behavior than thus far assumed. Am. J. Primatol. 71:409–418, 2009. © 2009 Wiley‐Liss, Inc.
Comparing the accuracy and precision of three techniques used for estimating missing landmarks when reconstructing fossil hominin crania
Authors: Neeser Rudolph , Ackermann Rebecca Rogers , Gain James
Published: February 2009

Various methodological approaches have been used for reconstructing fossil hominin remains in order to increase sample sizes and to better understand morphological variation. Among these, morphometric quantitative techniques for reconstruction are increasingly common. Here we compare the accuracy of three approaches—mean substitution, thin plate splines, and multiple linear regression—for estimating missing landmarks of damaged fossil specimens. Comparisons are made varying the number of missing landmarks, sample sizes, and the reference species of the population used to perform the estimation. The testing is performed on landmark data from individuals of Homo sapiens, Pan troglodytes and Gorilla gorilla, and nine hominin fossil specimens. Results suggest that when a small, same‐species fossil reference sample is available to guide reconstructions, thin plate spline approaches perform best. However, if no such sample is available (or if the species of the damaged individual is uncertain), estimates of missing morphology based on a single individual (or even a small sample) of close taxonomic affinity are less accurate than those based on a large sample of individuals drawn from more distantly related extant populations using a technique (such as a regression method) able to leverage the information (e.g., variation/covariation patterning) contained in this large sample. Thin plate splines also show an unexpectedly large amount of error in estimating landmarks, especially over large areas. Recommendations are made for estimating missing landmarks under various scenarios. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.
Stereoselective Synthesis of cis‐β‐Methyl‐ and Phenyl‐Substituted Alkenylboronates by Platinum‐Catalyzed Dehydrogenative Borylation
Authors: Ohmura Toshimichi , Takasaki Yuta , Furukawa Hideki , Suginome Michinori
Published: February 2009

Die Plätze getauscht: In Gegenwart eines Platin‐Phosphan‐Katalysators findet ein intramolekularer B(pin)/H‐Austausch statt (siehe Schema; B(pin)=4,4,5,5‐Tetramethyl‐1,3,2‐dioxaborolan‐2‐yl). Dabei bilden sich stereoselektiv cis‐β‐Methyl‐substituierte Alkenylboronate, die nützliche Synthesebausteine sind.

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Polymer‐Mediated Hierarchical and Reversible Emulsion Droplet Assembly
Authors: Weaver Jonathan V. M. , Rannard Steven P. , Cooper Andrew I.
Published: February 2009

Reversible Strukturbildung: Stabile funktionelle Emulsionsmikrotröpfchen bauen verschiedene komplexe makroskopische Flüssigkeitsstrukturen auf (siehe Bild). Der hierarchische Organisationsprozess wird durch Wechselwirkungen zwischen Polymertensiden auf der Tröpfchenoberfläche vermittelt. Weil die Wechselwirkungen reversibel sind, können die Strukturen in den Emulsionen durch einfache pH‐Änderungen aufgelöst werden.

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Singly Hydrogen Bonded Supramolecular Ligands for Highly Selective Rhodium‐Catalyzed Hydrogenation Reactions
Authors: Breuil Pierre‐Alain R. , Patureau Frederic W. , Reek Joost N. H.
Published: February 2009

Erst die H‐Brücke macht den Katalysator! Eine einzige Wasserstoffbrücke verbindet an ein Rhodiumzentrum koordinierte Liganden und erzeugt supramolekulare Katalysatoren für die asymmetrische Hydrierung. Die Estergruppe des Amiditliganden (siehe Schema) bildet eine weitere Wasserstoffbrücke zum koordinierten Substrat. Dieser Komplex ergab bei der Hydrierung einiger Estersubstrate die bislang höchsten Enantioselektivitäten.

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Exploiting a Bacterial Drug‐Resistance Mechanism: A Light‐Activated Construct for the Destruction of MRSA
Authors: Zheng Xiang , Sallum Ulysses W. , Verma Sarika , Athar Humra , Evans Conor L. , Hasan Tayyaba
Published: February 2009

A cunning and dangerous plan foiled! An enzyme‐specific molecular construct exploits the overexpression of β‐lactamase in several drug‐resistant bacteria. Specific photodynamic toxicity was detected towards β‐lactam‐resistant methicillin‐resistant Staphylococcus aureus (MRSA), whereby the usual mechanism for antibiotic resistance (cleavage of the β‐lactam ring) releases the phototoxic component from the prodrug (see picture; Q=quencher).

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Suppressed Particle Formation by Kinetically Controlled Ozone Removal: Revealing the Role of Transient‐Species Chemistry during Alkene Ozonolysis
Authors: Wolf Jan L. , Suhm Martin A. , Zeuch Thomas
Published: February 2009

The new approach of kinetically controlled ozone removal suppresses particle formation in laboratory ozonolysis experiments for methylcyclohexene and methylenecyclohexane (MCHa) at excess alkene concentrations (see graph). The results support the hypothesis that peroxy radicals are involved in organic nucleation and particle‐growth mechanisms.

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Switching the Chirality of Single Adsorbate Complexes
Authors: Parschau Manfred , Passerone Daniele , Rieder Karl‐Heinz , Hug Hans J. , Ernst Karl‐Heinz
Published: February 2009

Pumped up: Propene molecules form chiral complexes when adsorbed on a copper surface. Inelastically scattered tunneling electrons from the tip of a scanning tunneling microscope induce rotation or diffusion of the adsorbate on the surface. Higher tunneling currents can lead to conversion of the adsorbate into the opposite enantiomer.

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Nanoscale Chemical Imaging of the Reduction Behavior of a Single Catalyst Particle
Authors: de Smit Emiel , Swart Ingmar , Creemer J. Fredrik , Karunakaran Chithra , Bertwistle Drew , Zandbergen Henny W. , de Groot Frank M. F. , Weckhuysen Bert M.
Published: February 2009

A closer look: Investigation of the reduction properties of a single Fischer–Tropsch catalyst particle, using in situ scanning transmission X‐ray microscopy with spatial resolution of 35 nm, reveals a heterogeneous distribution of Fe0, Fe2+, and Fe3+ species. Regions of different reduction properties are defined and explained on the basis of local chemical interactions and catalyst morphology.

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Self‐Assembly Made Durable: Water‐Repellent Materials Formed by Cross‐Linking Fullerene Derivatives
Authors: Wang Jiaobing , Shen Yanfei , Kessel Stefanie , Fernandes Paulo , Yoshida Kaname , Yagai Shiki , Kurth Dirk G. , Möhwald Helmuth , Nakanishi Takashi
Published: February 2009

Fullerene flakes: A diacetylene‐functionalized fullerene derivative self‐organizes into flakelike microparticles (see picture). Both the diacetylene and C60 moieties can be effectively cross‐linked, which leads to supramolecular materials with remarkable resistivity to solvent, heat, and mechanical stress. Moreover, the surface of the cross‐linked flakelike objects is highly durable and water‐repellent.

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Inside Cover: Synthesis, Structure, and Complexation Properties of Partially and Completely Reduced meso‐Octamethylporphyrinogens (Calix[4]pyrroles) (Angew. Chem. Int. Ed. 9/2009)
Authors: Blangy Valeria , Heiss Christoph , Khlebnikov Vsevolod , Letondor Christophe , Stoeckli‐Evans Helen , Neier Reinhard
Published: February 2009

Calix[4]pyrrole is a beautiful, easy‐to‐synthesize macrocycle that completely changes its properties upon reduction and has been known for more than 120 years thanks to the work of Adolf von Baeyer. Its reduced form is described for the first time by H. Stoeckli‐Evans, R. Neier and co‐workers in their Communication on page 1688 ff. Metal complexes can be formed with great ease, thus creating an array of four directed hydrogen bonds.

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A Recombinant Fragment of Human Surfactant Protein D Lacking the Short Collagen‐Like Stalk Fails to Correct Morphological Alterations in Lungs of SP‐D Deficient Mice
Authors: Knudsen Lars , Wucherpfennig Katharina , Mackay Rose‐Marie , Townsend Paul , Mühlfeld Christian , Richter Joachim , Hawgood Samuel , Reid Kenneth , Clark Howard , Ochs Matthias
Published: February 2009

Emphysema‐like pathology is a characteristic feature of surfactant protein D (SP‐D) knock‐out mice. Treatment with a recombinant fragment of human SP‐D consisting of a short collagen‐like stalk (but not the entire collagen‐like domain of native SP‐D), neck, and carbohydrate recognizing domain (CRD) inhibits development of emphysema‐like pathology in SP‐D deficient mice. On the other hand, it has been shown that the entire collagen‐like domain is necessary for preventing SP‐D knock‐out mice from pulmonary emphysema development. Thus, in the present study, we aimed to elucidate the role of the short collagen‐like stalk for the function of the recombinant fragment of human SP‐D. We treated SP‐D knock‐out mice with a fragment of human SP‐D lacking the short collagen‐like stalk and compared the effects on lung morphology with results from untreated wild‐type and SP‐D knock‐out mice and from SP‐D knock‐out mice treated with a recombinant fragment of human SP‐D including the short collagen‐like stalk. The fragment of SP‐D lacking the short collagen‐like stalk failed to correct pulmonary emphysematous alterations demonstrating the importance of the short collagen‐like stalk for the biological activity of the recombinant fragment of human SP‐D. Anat Rec, 2009. © 2008 Wiley‐Liss, Inc.
Das städtische Mikroklima: Analyse für die Stadt‐ und Gebäudeplanung
Authors: Katzschner Lutz , Maas Anton , Schneider Andrea
Published: February 2009

Vor dem Hintergrund einer globalen Klimaerwärmung wird auch in der Stadt‐ und Gebäudeplanung die zunehmende Bedeutung des Mikroklimas im Hinblick auf den thermischen Komfort im Außen‐ und Innenraum sowie auf die Energieaufwendungen für Raumkonditionierung erkannt. Zur besseren Berücksichtigung dieses Aspektes in der Stadtplanung werden neben qualitativen vor allem quantitative Bewertungsverfahren benötigt. Globale Klimaveränderungen bewirken eine Intensivierung der städtischen Wärmeinsel und des Hitzestresses. In ausgewählten Stadtquartieren in Kassel wurden Untersuchungen zum thermischen Komfort in Außenräumen durchgeführt. Sie bestehen aus experimentellen Untersuchungen einschließlich von Befragungen zur Nutzung von urbanen Freiräumen und zum thermischen Empfinden sowie numerischen Simulationsberechnungen zur thermischen Belastung unter der Annahme der derzeitigen und zukünftigen regionalen Klimabedingungen. Die thermischen Bedingungen im Außenraum setzen sich im Gebäudeinnern fort, eine Verknüpfung der Innen‐ und Außenklimabetrachtungen muss daher erfolgen. Ziel einer Forschungsarbeit an der Universität Kassel ist die Untersuchung und Darstellung verschiedener Mikroklimate und ihres Einflusses auf das thermische Gebäudeverhalten (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Einfluss der vom menschlichen Körper absorbierten Solarstrahlung für das Wärmeempfinden in Gebäuden
Authors: Otto Frank
Published: February 2009

Das nachhaltige Bauen hat u. a. das Wohlbefinden des Menschen im Blick, das wesentlich vom Raumklima beeinflusst wird. Von zentraler Bedeutung für ein hohes Maß an Zufriedenheit mit der Umgebung ist thermische Behaglichkeit. Es ist zu erwarten, dass die Solarstrahlung vor allen Dingen in den Wintermonaten aufgrund der dominierenden diffusen Strahlung einen günstigen Einfluss auf Aufenthaltsräume hat. Hingegen kann eine direkte Besonnung im Sommer oder an strahlungsreichen Wintertagen in Fensternähe schnell zu unbehaglichen Zuständen führen, denen durch entsprechende Sonnenschutzmaßnahmen entgegengewirkt werden muss. Die Bedeutung der Solarstrahlung für das Wärmeempfinden wird auf der Grundlage einer Weiterentwicklung des Fanger schen Ansatzes anhand von Simulationsrechnungen aufgezeigt. Im Beitrag werden die wesentlichen Ergebnisse zusammengefasst (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Methoden zum Einsatz diskreter, webbasierter Wetterprognosen in Gebäudetechnik und Lastmanagement
Authors: Seerig Axel , Sagerschnig Carina
Published: February 2009

Prognosegeführte Regelungen verwenden zumeist kostenpflichtige stündliche Wetterprognosen, die auf der momentan gemessenen Außentemperatur basieren (z. B. Verschiebemethode) oder stündliche Prognosen eines nationalen meteorologischen Dienstes für den jeweiligen Standort. Mit Hilfe der prognostizierten Werte werden unter Verwendung geeigneter Modelle die jeweils benötigten Lastgänge vorausberechnet und weiterverarbeitet.

Das Internet hingegen bietet die Möglichkeit, von vielen Anbietern kostenfrei Wetterprognosen für beliebige Standorte zu erhalten. Gewöhnlich sind diese Prognosen zumindest für die maximale und minimale Außentemperatur für fünf bis maximal neun Tage im Voraus verfügbar. Für die meisten Anwendungen in der Gebäude‐ und Energietechnik werden jedoch Werte in stündlicher bzw. viertelstündlicher Auflösung benötigt. Gegenstand dieses Aufsatzes ist die Beschreibung eines Verfahrens zur Erstellung von zeitlich beliebig aufgelösten Wetterdaten auf Basis von frei verfügbaren Wetterprognosen aus dem Internet. Als Beispiele für den Einsatz der darauf basierenden prognosegeführten Regelung werden die Beladung eines Eisspeichers sowie die Lastprognose eines Gebäudes bzw. einer Liegenschaft besprochen (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gekoppelte Simulation zur Spezifikation von Heiz‐ und Kühlkörpern
Authors: Gritzki Ralf , Perschk Alf , Richter Wolfgang , Rösler Markus
Published: February 2009

Moderne Gebäude‐ und Raumkonzepte verlangen oft ein Umdenken gegenüber herkömmlichen Lösungen zur Heizung oder auch Kühlung der Gebäude. Oft ist jedoch nicht quantifizierbar, ob neue Ideen wirklich umsetzbar sind, da vereinfachte Abschätzungen eine zu große Unschärfe besitzen. Deshalb wurde ein von den Autoren maßgeblich entwickeltes und erfolgreich eingesetztes Programmsystem zur gekoppelten Gebäude‐, Anlagen‐ und Raumluftströmungssimulation mit einem weiteren räumlich und zeitlich hoch aufgelösten Modell für die Heiz‐ und Kühlkörpersimulation gekoppelt. Auf diese Weise können nicht nur Prüfszenarien aus der Heizungstechnik nachgebildet, sondern auch spezielle Betriebsverhältnisse oder Kühlkörper zur Raumtemperierung untersucht werden. Die Ansätze für die Modellierung sind kurz erläutert, ausgewählte Ergebnisse werden vorgestellt und diskutiert (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of human patient plasma ex vivo treatment on gene expression and progenitor cell activation of primary human liver cells in multi‐compartment 3D perfusion bioreactors for extra‐corporeal liver support
Authors: Schmelzer Eva , Mutig Kerim , Schrade Petra , Bachmann Sebastian , Gerlach Jörg C , Zeilinger Katrin
Published: February 2009

Cultivation of primary human liver cells in innovative 3D perfusion multi‐compartment capillary membrane bioreactors using decentralized mass exchange and integral oxygenation provides in vitro conditions close to the physiologic environment in vivo. While a few scale‐up bioreactors were used clinically, inoculated liver progenitors in these bioreactors were not investigated. Therefore, we characterized regenerative processes and expression patterns of auto‐ and paracrine mediators involved in liver regeneration in bioreactors after patient treatment. Primary human liver cells containing parenchymal and non‐parenchymal cells co‐cultivated in bioreactors were used for clinical extra‐corporeal liver support to bridge to liver transplantation. 3D tissue re‐structuring in bioreactors was studied; expression of proteins and genes related to regenerative processes and hepatic progenitors was analyzed. Formation of multiple bile ductular networks and colonies of putative progenitors were observed within parenchymal cell aggregates. HGF was detected in scattered cells located close to vascular‐like structures, expression of HGFA and c‐Met was assigned to biliary cells and hepatocytes. Increased expression of genes associated to hepatic progenitors was detected following clinical application. The results confirm auto‐ and paracrine interactions between co‐cultured cells in the bioreactor. The 3D bioreactor provides a valuable tool to study mechanisms of progenitor activation and hepatic regeneration ex vivo under patient plasma treatment. Biotechnol. Bioeng. 2009;103: 817–827. © 2009 Wiley Periodicals, Inc.
Gedanken zum Schutz der biologischen Vielfalt. Globales Unwissen contra Biodiversität
Authors: Wirth Roland , Glaw Frank
Published: February 2009

Kompetenter Biodiversitätsschutz setzt ausreichendes Wissen voraus, doch nicht einmal die Zahl der auf der Erde vorkommenden Arten ist annähernd bekannt. Über deren Bedrohungsstatus wissen wir noch viel weniger. Die Ursachen für die Bedrohung der Biodiversität sind vielfältig. Neben den Kernproblemen wie Bevölkerungswachstum und steigendem Ressourcenverbrauch wird erfolgreicher Biodiversitätsschutz auch durch einen Mangel an Taxonomen und Ökologen, Bürokratie, Politik und Fehlinterpretationen von Fakten behindert. Um die eklatanten Wissensdefizite abzubauen, müssen die Erfassung und der Schutz der Biodiversität viel stärker als globale Herausforderung begriffen und entsprechend finanziert werden.
Winkerkrabben: Bluff mit großer Schere
Authors: Wendler Silke
Published: February 2009

Die Männchen vieler Tierarten nutzen stark ausgeprägte sekundäre Geschlechtsmerkmale bei der Werbung um Weibchen ebenso wie beim Kräftemessen mit Rivalen. So auch die Winkerkrabben, deren Männchen eine extrem vergrößerte Schere haben. Geht bei einem Kampf eine Schere verloren, wächst diese vollständig nach. Männchen der Krabbenart Uca mjoebergi bilden allerdings eine nahezu funktionslose Schere nach und täuschen damit ihre Artgenossen.
Evolution Megalab: Die geheimnisvolle Vielfalt der Bänderschnecken
Authors: Anton Christian , Bossdorf Oliver
Published: February 2009

Innerartliche Variation ist eines der Schlüsselprinzipien der Evolution. Ein Paradebeispiel sind die Gehäuse der Schwarzmündigen Bänderschnecke (Cepaea nemoralis), deren extreme Farb‐ und Bänderungsvielfalt mit natürlicher Selektion durch Fraßfeinde und anderen Umweltbedingungen zusammenhängt. In einem europaweiten Projekt wollen Evolutionsbiologen nun herausfinden, wie die Verbreitung und Vielfalt der Bänderschnecke durch die aktuelle Klimaerwärmung beeinflusst wird.
ELISA – Tipps und Tricks zur Durchführung
Authors: Schrödel Andrea
Published: February 2009

Diejenigen unter Ihnen, die schon ELISA‐Tests im Labor durchführen, werden sich häufiger den Kopf über nicht reproduzierbare Werte und falsch positive Signale zerbrochen haben. Nachfolgende Tipps sollen versuchen, den Ursachen dieser Phänomene auf den Grund zu kommen.
Structurally Refined β‐Lactones as Potent Inhibitors of Devastating Bacterial Virulence Factors
Authors: Böttcher Thomas , Sieber Stephan A.
Published: February 2009

Disarmed forces: Inhibition of the central virulence regulator ClpP by structurally refined β‐lactones resulted in dramatically reduced production of devastating virulence factors, including pyrogenic toxin superantigens derived from pathogenic multiresistant Staphylococcus aureus strains. Targeting of this virulence regulator could present an attractive strategy for neutralizing the harmful effects of bacterial pathogens, and help the host immune response to eliminate the disarmed bacteria.

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Mass Transport in Multilayer Porous Metallic Membranes – Diagnosis, Identification and Validation
Authors: Edreva V. , Zhang F. , Mangold M. , Tsotsas E.
Published: February 2009

For a reliable description of mass transfer in membrane reactors the multilayer structure of the membrane is essential. This paper discusses methods which are sufficient to distinguish between homogeneous and composite membranes, and some others which are not. Different mass transport experiments (single gas permeation, isobaric diffusion, transient diffusion) with a porous metallic membrane consisting of two layers and the dusty gas model were used for this purpose. Simultaneous identification of mass transport parameters of both layers was achieved by modern optimization techniques on single gas permeation data. These parameters were validated by isobaric or transient diffusion measurements.
A Kinetic Study on Corn Gluten Hydrolysis
Authors: Apar D. K. , Özbek B.
Published: February 2009

In the present study, the hydrolysis of corn gluten was performed by using two commercial enzymes, Protamex and PTN, to investigate the reaction kinetics. The reactions were carried out for 10 min in 0.1 L of aqueous solutions containing 10, 20, 30 and 40 g protein L–1 corn gluten at various temperature and pH values. The progress of the reactions was monitored by a pH‐stat method. It was found that the kinetics of corn gluten hydrolysis by Protamex and PTN obey the Michaelis‐Menten model and higher catalytic yields were obtained with Protamex than PTN at all of the experimental conditions applied.
Minimum Circulation Velocity in a Spouted Bed Apparatus with Draft Tube
Authors: Kmiec A. , Ludwig W. , Szafran R.
Published: February 2009

Measurements of spouting characteristics were carried out in an apparatus consisting of two conical sections connected to a cylindrical section. Inside the lower conical section a draft tube was fixed. Results of minimum circulation velocity were obtained for an apparatus equipped with a draft tube of different inside diameters and lengths for different kinds of particles as well as for different static bed heights. Experimental data have been further analyzed to develop new correlations.
In Situ CO2 Capture in a Dual Fluidized Bed Biomass Steam Gasifier – Bed Material and Fuel Variation
Authors: Soukup G. , Pfeifer C. , Kreuzeder A. , Hofbauer H.
Published: February 2009

The AER (absorption enhanced reforming) process, based on the dual fluidized bed steam gasification process, uses a bed material which, apart from its function as heat carrier, acts as a CO2 transporting agent and selectively transfers CO2 from the gasification reactor to the combustion reactor. Thus, a hydrogen‐rich gas is produced (H2 55...70 vol.‐%db, CH4 8...13 vol.‐%db, CO 5...11 vol.‐%db as well as CO2 7...20 vol.‐%db). Seven different CaO containing bed materials were tested for their principal applicability to the AER process with special focus on their influence on tar production. The amount of tars was generally found to be five times lower than with conventional gasification (at 850 °C) despite the low gasification temperatures (600–700 °C). Due to these low gasification temperatures, biomass with high alkali contents (e.g., straw), indicating a low ash melting point (< 800 °C), can be used under AER conditions. In summary, the AER process is very effective owing to the integration of the heat of the chemical reaction of CO2 with CaO and the water‐gas shift reaction, which are both exothermic, into the gasification and the internal reforming of primary and secondary tars, which cuts off the formation of higher tars.
Limestone Attrition under Simulated Oxyfiring Fluidized‐Bed Combustion Conditions
Authors: Scala F. , Salatino P.
Published: February 2009

Limestone attrition by surface wear was studied during the flue gas desulfurization under simulated fluidized‐bed (FB) oxyfiring conditions and hindered calcination. Bench‐scale experimental tests were carried out using well‐established techniques previously developed for the characterization of sulfation and attrition of sorbents in air‐blown atmospheric FB combustors. The experimental limestone conversion and attrition results were compared with those previously obtained with the same limestone under simulated air‐blown combustion conditions. The differences in the conversion and attrition extents and patterns associated with oxyfiring as compared to air‐blown atmospheric combustion were highlighted and related to the different particle morphologies and thicknesses of the sulfate layer. It was noted that attrition could play an important role in practical circulating FB combustor operation, by effectively enhancing particle sulfation under both oxyfiring and air‐blown combustion conditions.
Calix[4]arenes as Molecular Platforms for Magnetic Resonance Imaging (MRI) Contrast Agents
Authors: Schühle Daniel T. , Schatz Jürgen , Laurent Sophie , Vander Elst Luce , Muller Robert N. , Stuart Marc C. A. , Peters Joop A.
Published: February 2009

The novel amphipilic conjugate of a calix[4]arene with four Gd–1,4,7,10‐ tetra(carboxymethyl)‐1,4,7,10‐tetraazacyclododecane (DOTA) chelates has potential as a magnetic resonance imaging contrast agent, both in its monomeric and in its micellar form. The system, illustrated here with its nuclear magnetic relaxation profile, shows good relaxivities, thanks to its high rigidity.

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An amphiphilic conjugate 1 of a calix[4]arene with four Gd–DOTA chelates (DOTA=1,4,7,10‐tetra(carboxymethyl)‐1,4,7,10‐tetraazacyclododecane) was prepared and the properties relevant to its application as a magnetic resonance imaging (MRI) contrast agent were investigated by NMR, dynamic light scattering (DLS), and cryo‐electron microscopy (cryo‐TEM). The compound aggregates in water; its critical micelle concentration (cmc) is 0.21 mM (or 0.84 mM for Gd) at 37 °C. The relaxivity of the aggregates at 37 °C and 20 MHz (18.3 s−1 per mM Gd or 73.2 s−1 per mM 1) is about twice that of the monomer. Nuclear magnetic relaxation dispersion (NMRD) profiles show the relaxivity of the monomer to be almost independent of the magnetic field strength up to 60 MHz. At higher concentrations, the NMRD profiles exhibit a maximum at about 20 MHz, which is typical for high molecular volumes. The average water residence lifetime is 1.20 μs at 298 K as determined by 17O NMR. The rotational correlation time of the monomer (390 ns at 37 °C) is very close to the optimal value predicted for high‐field contrast agents. Monomer as well as micelles are very rigid systems with negligible local contributions to the overall rotational dynamics. The binding to human serum albumin (HSA) is significant (KA=1.2×103 M−1) and the relaxivity of the HSA adduct at 20 MHz is 24.6 s−1 per mM Gd or 98.5 s−1 per mM 1.
Radial‐Position‐Controlled Doping of CdS/ZnS Core/Shell Nanocrystals: Surface Effects and Position‐Dependent Properties
Authors: Yang Yongan , Chen Ou , Angerhofer Alexander , Cao Y. Charles
Published: February 2009

Energy transfer in doped semiconductor nanocrystals: Mn‐doped CdS/ZnS nanocrystals show interesting photoluminescence and EPR properties that are strongly dependent on the radial position of Mn dopants inside nanocrystals (see graphic). Furthermore, the results suggest a two‐step mechanism for the energy transfer inside the doped nanocrystals.

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This paper reports a study of the surface effects and position‐dependent properties of Mn‐doped CdS/ZnS core/shell nanocrystals, which were prepared by using a three‐step synthesis method. The Mn‐doping level of these nanocrystals was determined by a combination of electron paramagnetic resonance spectroscopy and inductively coupled plasma atomic emission spectroscopy. These nanocrystals were further characterized by using transmission electron microscopy and fluorescence spectroscopy. First, we found that injecting a large excess of zinc stearate at the end of nanocrystal synthesis can sufficiently eliminate the surface‐trap states from the doped CdS/ZnS core/shell nanocrystals and enhance their photoluminescence (PL) quantum yield (QY). Second, our results demonstrate that the Mn‐PL QY is determined by the product of the efficiency of energy transfer from an exciton inside the CdS core to a Mn ion (ΦET) and the efficiency of the emission from the Mn ion (ΦMn). Third, ΦMn strongly depends on the radial position of Mn ions in the doped core/shell nanocrystals. The position‐dependent changes of ΦMn nearly perfectly correlate to those of the linewidth of Mn EPR peaks: the higher the ΦMn, the narrower the linewidth of the Mn EPR peak. Fourth, the results demonstrate that ΦET depends on the Mn‐doping level as well as the inverse sixth power of the distance between a Mn ion and the center of its host nanocrystal. Accordingly, we propose a two‐step mechanism for the energy transfer: 1) the energy transfer from an exciton inside the CdS core to a bound exciton around a Mn center, which is the rate‐determining step and follows the Förster mechanism, and 2) the energy transfer from the bound exciton to the Mn center, which might follow a mechanism such as dark exciton (triplet exciton) or Auger transfer.
Development and Characterization of Peptidic Fusion Inhibitors Derived from HIV‐1 gp41 with Partial D‐Amino Acid Substitutions
Authors: Gaston Fabrice , Granados Giovana C. , Madurga Sergio , Rabanal Francesc , Lakhdar‐Ghazal Faouzi , Giralt Ernest , Bahraoui Elmostafa
Published: February 2009

Interactions between C34 and N36: Synthetic peptides with D‐amino acid substitutions that mimic the human immunodeficiency virus (HIV) gp41 HR2 region may lead to new peptidic anti‐HIV‐1 drugs that retain potent antiviral activity while being more resistant to proteolytic degradation.

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The aim of this study was to design synthetic peptides with D‐amino acid substitutions that mimic the human immunodeficiency virus (HIV) gp41 HR2 region. The objective was to develop new and active C34 analogue peptides by introducing D‐amino acid point substitutions at nonessential sites for HR1–HR2 interaction without disrupting the structure of the peptide. Herein we report a study with C34L peptide analogues, including the enantiomer peptide C34D, the retro‐inverso analogue (RI), and two peptides with D‐amino acid point substitutions (C34M2 and C34M3). Our results show that, with the exception of RI, these peptides adopt an α‐helical structure and are, like C34L, able to interact with HR1, mimicked by the N36 peptide. Furthermore, we show that modifications introduced in C34M2, but not in C34M3, enhance its resistance to trypsin‐mediated hydrolysis and increase the stability of C34M2 in physiological medium. Interestingly, our results show that C34 peptide analogues C34M2 and C34M3, but not C34D and its RI analogue, retain their ability to inhibit HIV‐1 replication with an efficiency similar to that of the C34L peptide. These data underscore the interest in using D‐amino acids at specific sites in the C34 peptide sequence and may lead to a new strategy for the development of more stable and active anti‐HIV‐1 peptidic drugs.
Socioeconomic variation, number competence, and mathematics learning difficulties in young children
Authors: Jordan Nancy C. , Levine Susan C.
Published: February 2009

As a group, children from disadvantaged, low‐income families perform substantially worse in mathematics than their counterparts from higher‐income families. Minority children are disproportionately represented in low‐income populations, resulting in significant racial and social‐class disparities in mathematics learning linked to diminished learning opportunities. The consequences of poor mathematics achievement are serious for daily functioning and for career advancement. This article provides an overview of children's mathematics difficulties in relation to socioeconomic status (SES). We review foundations for early mathematics learning and key characteristics of mathematics learning difficulties. A particular focus is the delays or deficiencies in number competencies exhibited by low‐income children entering school. Weaknesses in number competence can be reliably identified in early childhood, and there is good evidence that most children have the capacity to develop number competence that lays the foundation for later learning. © 2009 Wiley‐Liss, Inc. Dev Disabil Res Rev 2009;15:60–68.
Longitudinal analysis of mammogenesis using a novel tetracycline‐inducible mouse model and in vivo imaging
Authors: Creamer Bradley A. , Triplett Aleata A. , Wagner Kay‐Uwe
Published: February 2009

We generated a novel mouse model, which expresses the tetracycline‐inducible transactivator under the regulation of the endogenous whey acidic protein gene. Using a tet‐responsive luciferase reporter transgene, we demonstrated that the Wap‐rtTA knockin allele allows a tightly controlled temporal and spatial expression of transgenes in the mammary gland in a ligand‐inducible manner. The longitudinal analysis of individual females throughout their reproductive cycles using in vivo bioluminescence imaging confirmed that the expression of the Wap‐rtTA knockin allele is highly upregulated during lactation. However, the extent of the transcriptional activation of the targeted Wap locus is dependent on the suckling stimulus and milk retrieval. In addition, we used WAP‐rtTA/TetO‐H2B–GFP double‐transgenic females to monitor the presence of GFP‐labeled parity‐induced mammary epithelial cells (PI‐MECs) during the postlactational involution period. The study shows that, unlike their progeny in mammary epithelial transplants as reported previously, PI‐MECs themselves may not belong to the long‐term label‐retaining epithelial subtype. genesis 47:234–245, 2009. © 2009 Wiley‐Liss, Inc.
Integrated Enzyme‐Based Biofuel Cells–A Review
Authors: Willner I. , Yan Y.‐M. , Willner B. , Tel‐Vered R.
Published: February 2009

Enzyme‐based biofuel cells provide versatile means to generate electrical power from biomass or biofuel substrates, and to use biological fluids as fuel‐sources for the electrical activation of implantable electronic medical devices, or prosthetic aids. This review addresses recent advances for assembling biofuel cells based on integrated, electrically contacted thin film‐modified enzyme electrodes. Different methods to electrically communicate the enzymes associated with the anodes/cathodes of the biofuel cell elements are presented. These include: (i) The reconstitution of apo‐enzymes on relay‐cofactor monolayers assembled on electrodes, or the crosslinking of cofactor‐enzyme affinity complexes assembled on electrodes. (ii) The immobilisation of enzymes in redox‐active hydrogels associated with electrodes. (iii) The use of nano‐elements, such as carbon nanotubes, for the electrical contacting of the enzyme electrodes comprising the biofuel cells. All three methods are implemented for the electrical contacting of oxidases and dehydrogenases with electrodes acting as anodes of biofuel cells, and for the electrical wiring of bilirubin oxidase, cytochrome oxidase, and laccase with electrodes, that yield the cathode units of the biofuel cells. Different methods to control the biofuel cells, operation by external stimuli are discussed, including the application of external magnetic fields, and the electrochemical switching of the biofuel cell operation.
Using the Barnes Language Assessment with older ethnic minority groups
Authors: Ramsey Victoria , Stevens Susan , Bryan Karen , Binder Julia , Cockle‐Hearne Jane
Published: February 2009

Objective

There are many issues concerning the assessment of older people from ethnic minority groups, the most significant being the language barrier experienced by those whose English is an additional language (EAL). This study aimed to test the hypothesis that EAL participants would score less well than those with English as a first language (EFL) on the sub‐tests of the Barnes Language Assessment (BLA), elucidate the reasons for any such differences and discuss the implications.

Methods

The Barnes Language Assessment (BLA) is an accurate tool providing information about expected patterns of language in different dementia syndromes. This study compares the performance of EAL participants with EFL participants. The BLA was administered to 144 participants, divided into sub‐groups with respect to age, gender and educational background, none of whom had a working diagnosis of dementia.

Results

Results suggest that EAL speakers performed less well compared to EFL speakers when other variables were matched. Significantly better BLA scores, at the one percent level, were found in both EAL and EFL groups with higher educational achievement for eight of the 15 sub‐tests.

Conclusion

Differences were found in performance on the BLA between EAL and EFL participants. The degree of difference between EAL and EFL speakers decreased as educational achievement rose. The consequences of these findings for service delivery and the problems of recruitment of older EAL participants are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Multiepitope peptide-loaded virus-like particles as a vaccine against hepatitis B virus–related hepatocellular carcinoma #
Authors: Ding Fei-Xiang , Wang Fang , Lu Yi-Ming , Li Ka , Wang Kai-Hui , He Xiao-Wen , Sun Shu-Han
Published: February 2009

To develop a hepatitis B virus (HBV) therapeutic vaccine that can induce a broad but specific immune response and significant antitumor effects both in vivo and in vitro, we inserted HBV X protein (HBx)-derived epitopes HBx(52-60), HBx(92-100), and HBx(115-123); a novel subdominant cytolytic T lymphocyte (CTL) epitope HBx(140-148); and the universal T helper epitope pan human leukocyte antigen DR-binding epitope into HBV core protein to form multiepitope peptide-loaded virus-like particles (VLPs). CTL responses against epitope-loaded VLPs were elicited by priming with VLP-pulsed dendritic cells in both HLA-A*0201 transgenic (Tg) mice and peripheral blood lymphocytes from HLA-A2+/HBx+ HBV-infected hepatocellular carcinoma (HCC) patients. The multiepitope peptide-loaded VLPs demonstrated significantly higher immunogenicity in Tg mice than any single responsive epitope. Significant antitumor effects were demonstrated both with primary cultured autologous HCC cells in vitro and tumor-bearing Tg mice in vivo in an HLA-A2–restricted and epitope-specific fashion. Conclusion: The significant antitumor effects both in vivo and in vitro demonstrate the potential of multiepitope peptide-loaded VLPs as a vaccine against HCC. (Hepatology 2009.)
Mechanical force induces type I collagen expression in human periodontal ligament fibroblasts through activation of ERK/JNK and AP‐1
Authors: Kook Sung‐Ho , Hwang Jung‐Min , Park Jong‐Sun , Kim Eun‐Mi , Heo Jung‐Sun , Jeon Young‐Mi , Lee Jeong‐Chae
Published: February 2009

Type I collagen (COL I) is the predominant collagen in the extracellular matrix of periodontal ligament (PDL), and its expression in PDL fibroblasts (PLF) is sensitive to mechanical force. However, the mechanism by which PLF induces COL I to respond to mechanical force is unclear. This study examined the nature of human PLF in mediating COL I expression in response to centrifugal force. Signal transduction pathways in the early stages of mechanotransduction involved in the force‐driven regulation of COL I expression were also investigated. Centrifugal force up‐regulated COL I without cytotoxicity and activated extracellular signal‐regulated kinase (ERK), c‐Jun N‐terminal kinase (JNK), and p38 kinase. ERK and JNK inhibitor blocked the expression of COL I but p38 kinase inhibitor had no effect. Centrifugal force activated activator protein‐1 (AP‐1) through dimerization between c‐Fos and c‐Jun transcription factors. ERK and JNK inhibitors also inhibited AP‐1‐DNA binding, c‐Fos nuclear translocation, and c‐Jun phosphorylation that were increased in the force‐exposed PLF. Further, transfecting the cells with c‐Jun antisense oligonucleotides almost completely abolished the force‐induced increase of c‐Jun phosphorylation and COL I induction. Our findings suggest that mechanical signals are transmitted into the nucleus by ERK/JNK signaling pathways and then stimulate COL I expression through AP‐1 activation in force‐exposed human PLF. J. Cell. Biochem. 106: 1060–1067, 2009. © 2009 Wiley‐Liss, Inc.
A new construction of perfect nonlinear functions using Galois rings
Authors: Feng Tao
Published: February 2009

For a prime p, we give a construction of perfect nonlinear functions from ℤ to ℤ when either of the following conditions holds: (1) n≥p; (2) n<p, and n is a composite number or is the sum of positive composite numbers. It follows that when n≥12, there is a perfect nonlinear function from ℤ to ℤ for any prime p. © 2009 Wiley Periodicals, Inc. J Combin Designs 17: 229‐239, 2009
Nanostructural analysis by atomic force microscopy followed by light microscopy on the same archival slide
Authors: Wagner Mathias , Kaehler Dirk , Anhenn Olaf , Betz Thomas , Awad Sally , Shamaa Ali , Theegarten Dirk , Linder Roland
Published: February 2009

Integrated information on ultrastructural surface texture and chemistry increasingly plays a role in the biomedical sciences. Light microscopy provides access to biochemical data by the application of dyes. Ultrastructural representation of the surface structure of tissues, cells, or macromolecules can be obtained by scanning electron microscopy (SEM). However, SEM often requires gold or coal coating of biological samples, which makes a combined examination by light microscopy and SEM difficult. Conventional histochemical staining methods are not easily applicable to biological material subsequent to such treatment. Atomic force microscopy (AFM) gives access to surface textures down to ultrastructural dimensions without previous coating of the sample. A combination of AFM with conventional histochemical staining protocols for light microscopy on a single slide is therefore presented. Unstained cores were examined using AFM (tapping mode) and subsequently stained histochemically. The images obtained by AFM were compared with the results of histochemistry. AFM technology did not interfere with any of the histochemical staining protocols. Ultrastructurally analyzed regions could be identified in light microscopy and histochemical properties of ultrastructurally determined regions could be seen. AFM‐generated ultrastructural information with subsequent staining gives way to novel findings in the biomedical sciences. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Authentication of the 31 species of toxic and potent Chinese Materia Medica by light microscopy, part 3: Two species of T/PCMM from flowers and their common adulterants
Authors: Chu Chu , Xia Li , Bai Li‐Ping , Li Qin , Li Ping , Chen Hu‐Biao , Zhao Zhong‐Zhen
Published: February 2009

Toxic and potent Chinese Materia Medica (T/PCMM) has become a hot and sensitive topic as more and more people around the world are interested in the safety of herbal medicines. T/PCMM is irreplaceable in treating some diseases; but it can easily cause serious problems if confused with other herbal medicines. Accurate identification is essential to ensure their safe use, but up to now, the literature on the authentication of T/PCMM is scant. Thus, we are undertaking a study of 31 T/PCMM originating from plants, animals, minerals, and secreta. Our previous study established microscopic observation as a simple, fast, accurate, and convenient method for identifying and authenticating animal and seed T/PCMM. This study focused on the authentication of flower T/PCMM as a part of the whole study. The flower T/PCMM studies were derived from two species, Datura metel L. (Flos Daturae) and Rhododendron molle G. Don (Flos Rhododendri Mollis). Other species easily confused with these two were also examined and characterized. Using the microscope camera, normal light and polarized light microscopy, we determined the macroscopic and microscopic features of the flowers; in addition, the oil immersion lens was used to study the pollen grain characteristics. The results demonstrated that flower T/PCMM can be identified and authenticated using a light microscope equipped with an oil immersion lens. This same equipment can be easily used to characterize other herbal flower medicines. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Independent sets of maximal size in tensor powers of vertex‐transitive graphs
Authors: Ku Cheng Yeaw , McMillan Benjamin B.
Published: February 2009

Let G be a connected, nonbipartite vertex‐transitive graph. We prove that if the only independent sets of maximal cardinality in the tensor product G × G are the preimages of the independent sets of maximal cardinality in G under projections, then the same holds for all finite tensor powers of G, thus providing an affirmative answer to a question raised by Larose and Tardif (J Graph Theory 40(3) (2002), 162–171). © 2009 Wiley Periodicals, Inc. J Graph Theory 60: 295‐301, 2009