bluuebunny/crossref_metadata_2025_split huggingface dataset:
Otto Kleinschmidt – Pionier der Vogelkunde und des Artbegriffes
Authors: Irsch Wilhelm 
Published: April 2010

AbstractDer Pfarrer Otto Kleinschmidt war nicht nur naturwissenschaftlich, sondern auch musisch begabt: Seine in Figur, Haltung, Stellung, Farbgebung und Zeichnung hervorragenden Bilder begeisterten die Leser von Büchern wie beispielsweise den “Singvögeln der Heimat” (1911, mit 12 Auflagen bis 1963). Seine “Formenkreislehre” polarisierte Gegner und Anhänger gleichermaßen.
Xanthomonas: Die Hacker unter den Pflanzenbakterien
Authors: Brennicke Axel 
Published: April 2010

AbstractIm Krieg zwischen Lebewesen und ihren Schmarotzern werden alle Register gezogen. Viele Bakterien injizieren spezielle Proteine in Pflanzenzellen, um deren Gene für ihre eigenen Zwecke einzusetzen. Jetzt fanden Wissenschaftler an der Universität Halle heraus, wie die Proteine aus Bakterien die genetischen Schalter in der Pflanzenzelle erkennen. Nach diesem Vorbild lassen sich künstliche Proteine konstruieren, die für nützliche Veränderungen an Kulturpflanzen und anderen Organismen gezielt eingesetzt werden können.
Mega‐Rolle für microRNAs
Authors: Kronberg Inge 
Published: April 2010

AbstractEmbryonale Stammzellen entstehen wie alle Körperzellen aus der Zygote, haben aber bemerkenswerte Fähigkeiten: Sie können sich beliebig oft teilen und erneuern sich dabei selbst oder differenzieren sich schrittweise weiter zu funktionsfähigen Körperzellen (Pluripotenz). Die Entwicklungsrichtung wird von winzigen RNA‐Abschnitten (microRNAs) beeinflusst, die sogar reife, ausdifferenzierte Körperzellen zurück in den pluripotenten Zustand bringen können. Diese Reprogrammierung verspricht vielfältige Möglichkeiten in der regenerativen Medizin und anderen stammzellbasierten Forschungsrichtungen.
Ein Magnetometer im Schnabel aller Vögel?
Authors: Fleissner Gerta , Fleissner Günther , Falkenberg Gerald 
Published: April 2010

AbstractEisenhaltige kurze Nervenäste im Oberschnabel von verschiedenen Vogelarten erfüllen alle strukturellen und biophysikalischen Voraussetzungen eines Magnetfeldrezeptors. Die einheitliche Form der Dendriten und ihre Anordnung in der Schnabelhaut lassen auf einen ursprünglichen Mechanismus der Vögel schließen, der als Basis für eine Magnetkarte bei variablen Aufgaben der Orientierung genutzt werden kann: beim Vogelzug über weite Strecken, beim Heimfinden von unterschiedlichen Plätzen in der weiteren Umgebung des Heimatortes oder auch beim Herumstreifen in der nächsten Umgebung des Nistplatzes.
Western‐Blot Teil 1: Die Blotting‐Technik
Authors: Schrödel Andrea 
Published: April 2010

AbstractDas Verfahren des Western‐Blots wird im Bereich der Proteinbiochemie für den Nachweis von bestimmten Proteinen oder Protein‐Veränderungen (beispielsweise Phosphorylierung) durchgeführt und stellt in der Medizin ein wichtiges Werkzeug für die Diagnostik von Infektionskrankheiten (Nachweis von Antikörpern im Serum) dar. Hierbei werden Proteine im SDS‐Polyacrylamidgel aufgetrennt, auf eine Membran transferiert und in einer antikörperabhängigen Reaktion durch den Umsatz bestimmter Substrate nachgewiesen.
A new RF and Microwave Engineering course enriched with advanced technologies
Authors: Aydin Elif , Cagiltay Nergiz 
Published: April 2010

AbstractIn this study, a curriculum model including recent developments and technologies in the Radio Frequency (RF) and Microwave Engineering field by using a blended approach is proposed. This study covers the description of the content of theoretical and hands on applications, the integration model of the technological tools into the proposed curriculum, and the instructional approaches used in the new course design. The main goal of the course is to prepare students for future professional careers in RF and Microwave Engineering by supporting them with new instructional technologies. The secondary goal of the course is to better prepare the students for the sequence of senior courses in the Electrical and Electronics Engineering program of Atilim University. The course is structured with a balance between theory and laboratory, including remote and in lab measurement experiments as well as modeling and designing microwave components by means of computer tools and design fabrication. The newly designed course is implemented at the Atilim University. The study also reports the first semester implementation. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 634–645, 2012
Striving to be ‘good’ mothers: abused women's experiences of mothering
Authors: Lapierre Simon 
Published: April 2010

AbstractSo far, limited work has focused on women's experiences of mothering in the context of domestic violence. This article presents the findings of a study that investigated women's experiences of mothering in the context of domestic violence and, while it accounts for the difficulties and challenges these women face, it emphasises their desire to be ‘good’ mothers and the strategies they develop in order to achieve ‘good’ mothering. The findings demonstrate that abused women typically strive to be ‘good’ mothers, which requires them to put their children first and to protect and care for them. The recognition of these strategies provides ground to question current professional practices and to develop interventions that will best support women and children living with domestic violence. Copyright © 2010 John Wiley & Sons, Ltd.
Strategies for the Inhibition of Protein Aggregation in Human Diseases
Authors: Bartolini Manuela , Andrisano Vincenza 
Published: April 2010

AbstractProtein misfolding and aggregation has been related to several human disorders, generally termed protein aggregation diseases. These diseases include neurodegenerative disorders such as Alzheimer's, Parkinson's, and Huntington's diseases and peripheral disorders such as systemic amyloidosis and type 2 diabetes. The complexity of the aggregation processes and the intertwined events account for the fact that no effective disease‐modifying treatments for these disorders are currently available. Nevertheless, in‐depth research into the aggregation processes has recently yielded major insights into some key mechanisms of aggregation‐mediated cell toxicity, offering new targets for drug development. In addition, recent findings in the field have identified similar features, revealing the possibility of shared mechanisms and hence potential common approaches for intervention. This review aims to give an overview of potential strategies for tackling protein aggregation and its associated toxicity, focusing on protein aggregation in human disease.
The Catalytic Conversion of Thiophenes over Large H‐ZSM‐5 Crystals: An X‐Ray, UV/Vis, and Fluorescence Microspectroscopic Study
Authors: Kox Marianne H. F. , Mijovilovich Ana , Sättler Jesper J. H. B. , Stavitski Eli , Weckhuysen Bert M. 
Published: April 2010

AbstractX‐ray absorption, UV/Vis, and fluorescence microspectroscopy have been used to characterize the catalytic conversion of thiophene derivatives within the micropores of an individual H‐ZSM‐5 zeolite crystal. Space‐resolved information into the Si/Al ratios and sulfur content was provided by X‐ray absorption microspectroscopy. X‐ray absorption near‐edge spectroscopy spectral information and modeling indicated the presence of a sulfur atom, in close proximity of two oxygen atoms, that is, at approximately 2.5 Å. Space‐resolved spectroscopic measurements provided experimental evidence for the formation of conjugated carbocationic reaction intermediates by opening of the thiophene ring. The molecular alignment of reaction products within the straight pores of the individual H‐ZSM‐5 zeolite crystals was observed with polarized light UV/Vis microspectroscopy. In addition, confocal fluorescence microscopy revealed the 3D distribution of different reaction products and demonstrated the influence of the H‐ZSM‐5 crystal’s intergrowth structure and its related molecular diffusion barriers.
Formation of Furfural in Catalytic Transformation of Levoglucosan over Mesoporous Materials
Authors: Käldström M. , Kumar N. , Heikkilä T. , Tiitta M. , Salmi T. , Murzin D. Yu. 
Published: April 2010

AbstractCatalytic transformations of levoglucosan (1‐6‐anhydro‐β‐D‐glucopyranose) and furfural were carried out in a fixed‐bed reactor at 573 K over mesoporous materials. Proton forms of MCM‐41, MCM‐48, SBA‐15, and platinum form of MCM‐48 catalysts were tested in the reaction, whereas H‐Beta and quartz sand were used as reference materials. The yield of the transformation products was substantially influenced by the catalyst structures. Oxygenated species were the main liquid products, consisting mainly of aldehydes and furfural. The formation of furfural was the highest over MCM‐41 catalyst followed by SBA‐15, MCM‐48, and H‐Beta catalyst. All catalysts were to some extent deactivated due to coke formation. However, it was possible to successfully regenerate the spent catalysts without changing the structure.
Culture Conditions and Investigation of Bioreactor Configurations for Lipase Production by Rhizopus oryzae
Authors: López E. , Deive F. J. , Longo M. A. , Sanromán M. Á. 
Published: April 2010

AbstractLipolytic enzymes are the subject of great industrial and academic interest. For this reason, a detailed study of lipolytic enzyme production by the fungus Rhizopus oryzae is tackled, and several steps from plate to shake flasks and bioreactor cultures are investigated in order to propose an optimized strategy to perform the biological process. The suitability of several lipidic compounds and surfactants is assessed. Triton X‐100 (5 g/L) gives the highest activities with a maximum value of 6320 U/L which is 10‐fold the value attained in cultures without addition of lipidic compounds. As there are almost no studies on bench‐scale bioreactors, two bioreactor configurations, stirred tank and air‐lift, are investigated to determine the most suitable one to carry out the biological reaction. It is demonstrated that the lipolytic activity is strongly enhanced when a stirred‐tank bioreactor is used with a maximum value of 3521 U/L within two days which is clearly higher than the values produced by other recently reported species.
Reversible Coordination of Dioxygen by Tripodal Tetraamine Copper Complexes Incorporated in a Porous Silica Framework
Authors: Suspène Clément , Brandès Stéphane , Guilard Roger 
Published: April 2010

AbstractThe present study reports the synthesis and rational design of porous structured materials by using a templating method. A tetraethoxysilylated tripodal tetraamine (TREN) was covalently incorporated in a silica framework with a double imprint: A surfactant template and a metal ion imprint. The presence of a cationic surfactant (CTAB) endowed the material with a high porosity, and the tripodal or square‐pyramidal topology of the ligand was preserved thanks to the use of the silylated CuII complex. After removal of the surfactant and de‐metalation, the incorporated tetraamine was quantitatively complexed by CuCl2 and the material has shown after thermal activation that a reversible binding of O2 on the metal ions occurred. This chemisorption process was monitored by UV/Vis and EPR spectroscopies, and the Cu:O2 adduct was postulated to be an end‐on μ‐η1:η1‐peroxodicopper(II) complex bridged by a chloride ion. The CuI‐active species, formed during the activation step, were fully recovered during several O2 binding cycles. The high reactivity of the copper complexes and the room‐temperature stability of the dioxygen adduct were explained by the fine adaptability of the tripodal ligand to different geometries, the confinement of the active sites in the hybrid silica that protect them from degradation by a control of the metal‐ion microenvironment, as well as the short‐range lamellar order of the copper complexes in the framework.
Synthesis of Symmetrical Multichromophoric Bodipy Dyes and Their Facile Transformation into Energy Transfer Cassettes
Authors: Bozdemir O. Altan , Cakmak Yusuf , Sozmen Fazli , Ozdemir Tugba , Siemiarczuk Aleksander , Akkaya Engin U. 
Published: April 2010

AbstractMultichromophoric boron‐dipyrromethene (Bodipy) dyes synthesized on phenylene‐ethynylene platforms have been be converted to energy transfer cassettes in a one‐step chemical transformation. Excitation energy transfer processes in these highly symmetrical derivatives were studied in detail, including time‐resolved fluorescence spectroscopy techniques. Excitation spectra and the emission lifetimes suggest efficient energy transfer between the donor and acceptor chromophore. These novel energy transfer cassettes, while highlighting a short‐cut approach to similar energy transfer systems, could be useful as large pseudo‐Stokes shift multichromophoric dyes with potential applications in diverse applications.
Magnetically Recoverable Core–Shell Nanocomposites with Enhanced Photocatalytic Activity
Authors: Ye Miaomiao , Zhang Qiao , Hu Yongxing , Ge Jianping , Lu Zhenda , He Le , Chen Zhonglin , Yin Yadong 
Published: April 2010

AbstractCore–shell structured Fe3O4/SiO2/TiO2 nanocomposites with enhanced photocatalytic activity that are capable of fast magnetic separation have been successfully synthesized by combining two steps of a sol–gel process with calcination. The as‐obtained core–shell structure is composed of a central magnetite core with a strong response to external fields, an interlayer of SiO2, and an outer layer of TiO2 nanocrystals with a tunable average size. The convenient control over the size and crystallinity of the TiO2 nanocatalysts makes it possible to achieve higher photocatalytic efficiency than that of commercial photocatalyst Degussa P25. The photocatalytic activity increases as the thickness of the TiO2 nanocrystal shell decreases. The presence of SiO2 interlayer helps to enhance the photocatalytic efficiency of the TiO2 nanocrystal shell as well as the chemical and thermal stability of Fe3O4 core. In addition, the TiO2 nanocrystals strongly adhere to the magnetic supports through covalent bonds. We demonstrate that this photocatalyst can be easily recycled by applying an external magnetic field while maintaining their photocatalytic activity during at least eighteen cycles of use.
Remarkably Efficient Photocurrent Generation Based on a [60]Fullerene–Triosmium Cluster/Zn–Porphyrin/Boron–Dipyrrin Triad SAM
Authors: Lee Chang Yeon , Jang Jae Kwon , Kim Chul Hoon , Jung Jaehoon , Park Bo Keun , Park Jihee , Choi Wonyong , Han Young‐Kyu , Joo Taiha , Park Joon T. 
Published: April 2010

AbstractA new artificial photosynthetic triad array, a [60]fullerene–triosmium cluster/zinc–porphyrin/boron–dipyrrin complex (1, Os3C60/ZnP/Bodipy), has been prepared by decarbonylation of Os3(CO)8(CN(CH2)3Si(OEt)3)(μ3‐η2:η2:η2‐C60) (6) with Me3NO/MeCN and subsequent reaction with the isocyanide ligand CNZnP/Bodipy (5) containing zinc porphyrin (ZnP) and boron dipyrrin (Bodipy) moieties. Triad 1 has been characterized by various spectroscopic methods (MS, NMR, IR, UV/Vis, photoluminescence, and transient absorption spectroscopy). The electrochemical properties of 1 in chlorobenzene (CB) have been examined by cyclic voltammetry; the general feature of the cyclic voltammogram of 1 is nine reversible one‐electron redox couples, that is, the sum of those of 5 and 6. DFT has been applied to study the molecular and electronic structures of 1. On the basis of fluorescence‐lifetime measurements and transient absorption spectroscopic data, 1 undergoes an efficient energy transfer from Bodipy to ZnP and a fast electron transfer from ZnP to C60; the detailed kinetics involved in both events have been elucidated. The SAM of triad 1 (1/ITO; ITO=indium–tin oxide) has been prepared by immersion of an ITO electrode in a CB solution of 1 and diazabicyclo‐octane (2:1 equiv), and characterized by UV/Vis absorption spectroscopy, water contact angle, X‐ray photoelectron spectroscopy, and cyclic voltammetry. The photoelectrochemical properties of 1/ITO have been investigated by a standard three‐electrode system in the presence of an ascorbic acid sacrificial electron donor. The quantum yield of the photoelectrochemical cell has been estimated to be 29 % based on the number of photons absorbed by the chromophores. Our triad 1 is unique when compared to previously reported photoinduced electron‐transfer arrays, in that C60 is linked by π bonding with little perturbation of the C60 electron delocalization.
Mechanistic Study of the Reaction of Thiol‐Containing Enzymes with α,β‐Unsaturated Carbonyl Substrates by Computation and Chemoassays
Authors: Paasche Alexander , Schiller Markus , Schirmeister Tanja , Engels Bernd 
Published: April 2010

AbstractWe investigated the reactions between substituted α,β‐unsaturated carbonyl compounds (Michael systems) and thiols by computations as well as chemoassays. The results give insight into variations in the underlying mechanisms as a function of the substitution pattern. This is of interest for the mechanisms of inhibition of the SARS coronavirus main protease (SARS‐CoV Mpro) by etacrynic acid derivatives as well as for the excess toxicity of substituted α,β‐unsaturated carbonyl compounds. This study compares possible reaction courses including 1,4‐addition followed by a ketonization step, and underscores the importance of a base‐catalyzed step for the reactivity of thiol groups in enzymes. Phenyl and methyl substituents at the Michael system decrease the reactivity of the electrophilic compound, but chlorophenyl substituents partly recover the reactivity. Computations also indicate that electron‐pushing substituents lead to a change in the reaction mechanism. The conformation of the Michael system is also found to significantly influence reactivity: thes‐cisconformation leads to higher reactivity than thes‐transconformation. The computed data explain the trends in measured inhibition potencies of substituted α,β‐unsaturated carbonyl compounds and of reaction rates in chemical assays. They also indicate that the reversibility of inhibition does not stand in contrast to the formation of a new covalent bond between inhibitor and protease.
Triple Phase Boundary Photovoltammetry: Resolving Rhodamine B Reactivity in 4‐(3‐Phenylpropyl)‐Pyridine Microdroplets
Authors: Collins Andrew M. , Zhang Xiaohang , Scragg Jonathan J. , Blanchard Gary J. , Marken Frank 
Published: April 2010

AbstractRhodamine B base is employed as a photoactive redox system in a liquid | liquid | electrode triple phase boundary electrochemical experiment. Microdroplets of the water‐immiscible 3‐(4‐phenylpropyl)‐pyridine (PPP) containing rhodamine B are deposited onto a basal plane pyrolytic graphite electrode surface which is then immersed into an aqueous solution containing 0.5 Mphosphate buffer solution (pH 12). In cyclic voltammetry experiments, it is shown that dark reduction of rhodamine B to leuco‐rhodamine B in PPP occurs in two steps—both one electron processes—and the re‐oxidation occurs in a single two‐electron process. Voltammetric signals are consistent with Na+transfer (for the first reduction step) and proton transfer (for the second reduction step) coupled to the electron transfer. A proton‐driven disproportionation reaction (withkdis=3 mol−1 dm3 s−1at pH 12) is observed for the one‐electron reduced intermediate. In the presence of light, a new photocatalysed oxidation process for the two‐electron conversion of leuco‐rhodamine B to rhodamine B is observed. Photoexcitation of rhodamine B is shown to trigger an effective photo‐comproportionation mechanism. Quantitative insights into the dark and photomechanisms are obtained by comparison of rhodamine B and rhodamine B octadecylester and by applying an approximate numerical simulation procedure based on DigiSim.
Investigation on the Second Part of the Electromagnetic SERS Enhancement and Resulting Fabrication Strategies of Anisotropic Plasmonic Arrays
Authors: Cialla Dana , Petschulat Jörg , Hübner Uwe , Schneidewind Henrik , Zeisberger Matthias , Mattheis Roland , Pertsch Thomas , Schmitt Michael , Möller Robert , Popp Jürgen 
Published: April 2010

AbstractIn general, the electromagnetic mechanism is understood as the strongest contribution to the overall surface‐enhanced Raman spectroscopy (SERS) enhancement. Due to the excitation of surface plasmons, a strong electromagnetic field is induced at the interfaces of a metallic nanoparticle leading to a drastic enhancement of the Raman scattering cross‐section. Furthermore, the Raman scattered light expierences an emission enhancement due to the plasmon resonances of the nanoantennas. Herein, this second part of the electromagnetic enhancement phenomenon is investigated for different Raman bands of crystal violet by utilizing the anisotropic plasmonic character of gold nanorhomb SERS arrays. We aim at evaluating the effects of localized and propagating surface plasmon polariton modes as well as their combination on the scattered SERS intensity. From that point of view, design and fabrication strategies towards the fabrication of SERS arrays for excitation wavelengths in the visible and near‐infrared (NIR) spectral region can be given, also using a double‐resonant electromagnetic enhancement.
Monolithisches Mauerwerk aus Leichtbetonsteinen erfüllt die Anforderungen der Energieeinsparverordnung 2009
Authors: Schrenk Johannes , Maier Martin 
Published: April 2010

AbstractDie Energieeinsparverordnung (EnEV) 2009 beinhaltet verschärfte Anforderungen an den Jahresprimärenergiebedarf und den Transmissionswärmeverlust von Gebäuden. Damit sinkt der durchschnittliche U‐Wert von Außenwänden auf 0,28 W/(m2K). Mauersteine aus haufwerksporigem Leichtbeton wurden in den letzten Jahren wärmetechnisch so verbessert, dass sich diese Anforderungen mit Mauerwerksdicken von 36,5 cm problemlos erfüllen lassen. Selbst die Kriterien für ein KfW‐Effizienzhaus 70 oder 55 lassen sich auf diese Weise mit monolithischem Mauerwerk ohne zusätzliche Dämmung noch einhalten.Monolithic masonry made of lightweight concrete blocks meets demands of energy saving regulations. The Decree for Saving Energy (Energieeinsparverordnung, EnEV — regulation for energy saving in buildings and building systems) 2009 consists stronger regulations for the yearly demand of energy and the loss of transmission heat of buildings. Therefore the average U‐Value for enclosure walls decreases to 0.28 W/(m2K). Blocks made of aggregate lightweight concrete have been improved by the industry concerning their thermal conductivity in the last years, so these demands can be fulfilled with masonry in 36,5 cm thickness. Even the criteria of a KfW Efficiency House 70 or 55 can be fulfilled in this way with monolithic masonry without an additional thermal insulation.