bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and Characterization of Potential Cancer Stem Cells from Solid Human Tumors—Potential Applications
Authors: Dobbin Zachary C. , Landen Charles N.
Published: December 2013

Cancer stem cells (CSCs) are a subpopulation of cells within a heterogeneous tumor that have enhanced biologic properties, e.g., increased capacity for self‐renewal, increased tumorigenicity, enhanced differentiation capacity, and resistance to chemo‐ and radiotherapies. This unit describes protocols to isolate and characterize potential cancer stem cells from a solid tumor. These involve creating a single‐cell suspension from tumor tissue, tagging the cell subpopulations of interest, and sorting them into different populations. The sorted subpopulations can be evaluated for their ability to meet the functional requirements of a CSC, which primarily include increased tumorigenicity in an in vivo xenograft assay. Use of the protocols described in this unit makes it possible to study populations of cells that may have properties of CSCs. Curr. Protoc. Pharmacol. 63:14.28.1‐14.28.19. © 2013 by John Wiley & Sons, Inc.
Quantitative Analysis of Phosphoinositide 3‐Kinase (PI3K) Signaling Using Live‐Cell Total Internal Reflection Fluorescence (TIRF) Microscopy
Authors: Johnson Heath E. , Haugh Jason M.
Published: December 2013

This unit focuses on the use of total internal reflection fluorescence (TIRF) microscopy and image analysis methods to study the dynamics of signal transduction mediated by class I phosphoinositide 3‐kinases (PI3Ks) in mammalian cells. The first four protocols cover live‐cell imaging experiments, image acquisition parameters, and basic image processing and segmentation. These methods are generally applicable to live‐cell TIRF experiments. The remaining protocols outline more advanced image analysis methods, which were developed in our laboratory for the purpose of characterizing the spatiotemporal dynamics of PI3K signaling. These methods may be extended to analyze other cellular processes monitored using fluorescent biosensors. Curr. Protoc. Cell Biol. 61:14.14.1‐14.14.24. © 2013 by John Wiley & Sons, Inc.
Beyond the Qualitative/Quantitative “Divide”
Authors: Michelle Carolyn , Davis Charles H.
Published: December 2013

This chapter introduces readers to Q methodology, a methodological hybrid concerned with revealing similarities and differences in people's viewpoints, attitudes, beliefs, and experiences. The history of Q methodology is first outlined, and its key principles and processes are explained, before a brief case study is presented in which Q methodology was used in an online survey of cross‐cultural responses to James Cameron's 2009 feature filmAvatar. Here, readers are taken behind the scenes to reflect on the methodological challenges faced, while some of the unique insights that Q methodology provided in this case are highlighted. Finally, the major strengths and limitations of Q methodology are discussed. It is an approach that has considerable potential to shed light on many key questions in contemporary media studies.
Memories of Films and Cinema‐Going inMonterrey,Mexico
Authors: Frankenberg Lorena , Lozano José Carlos
Published: December 2013

Qualitative interviews, a methodology increasingly popular in media and communication studies, are not only useful for studying the meaning construction of different kinds of producers or audiences in the present. They are also useful for exploring past media experiences and for looking at the meaning and importance media had in the past for different types of publics by retrieving memories, feelings, and facts not taken into account in data collected by the media industries. To offer insight into the methodological issues and theoretical considerations media scholars need to address when using this technique, this chapter reports the use of focused interviews in a study on the screen culture of cinema‐goers of Monterrey, Mexico, from the 1930s to the 1960s and discusses the methodological challenges of interpreting highly selective, subjective, and distorted‐by‐time memories of cinema‐going in senior informants.
Conducting Media Ethnographies in
A
frica
Authors: Bosch Tanja
Published: December 2013

This chapter explores the methodology of ethnography in postcolonial Africa, with specific reference to anthropological media research. The chapter draws on an ethnography of a local radio station in South Africa as a starting point from which to make several observations about media ethnographies and anthropological approaches to media production and consumption. It outlines how the chosen methodology revealed unique characteristics of the local, as well as how the findings and experiences could be related to national and regional contexts. Moreover, the chapter explores notions of reflexive “backyard” or “native” ethnographies, and reveals the complex relational issues that can arise from this approach. This case study is premised on the notion of media as a collective mediation of culture; and argues that the practice of ethnography allows for a refreshing departure from the more common armchair textual analyses that permeate media studies.
Autoethnography in Media Studies
Authors: Uotinen Johanna
Published: December 2013

This chapter discusses the possibilities and limits of autoethnography for media studies. As an example, I use my own technological experiences with television as it relates to the digitalization process of television broadcasting that occurred in Finland. The chapter demonstrates how autoethnography makes it possible to study media‐related everyday practices that are difficult to research with other methods, as these practices have become invisible due their repetitive and mundane nature. To conclude, I suggest that autoethnography is a method that offers possibilities for connecting the personal to the cultural and social and thus grasps everyday‐based small agency.
The Basics of Experimental Research in Media Studies
Authors: Leshner Glenn
Published: December 2013

This chapter discusses the basics of experimental design used in media studies research. Many scientific researchers believe, with good reason, that the controlled experiment is perhaps the best research method for determining a cause and effect relationship between variables. The chapter considers the types of research questions experiments can address, how the experiment can demonstrate causal relationships between variables, common experimental designs, data collection and interpretation, and ethical considerations. A major part of the chapter deals with internal validity pitfalls, such as confounds, randomization, and how to determine acceptable sample sizes. It also considers what may be regarded as controversial issues in experimental research, such as generalizability (or lack thereof), how to create treatment variance, the issues involved with creating message variance, and handling the issues of design complexity and manipulation checks.
Eye Tracking in Media Studies
Authors: Geise Stephanie
Published: December 2013

This chapter provides an overview of the fundamentals, theories, and application of eye tracking as a method of communication and media studies. The examined “object for analysis” – the process of visual perception – is understood here as a multidimensional phenomenon, to which justice can be done only through a multifaceted theoretical foundation. An approach to the method of eye tracking must therefore start with theoretical considerations on the physiological and psychological aspects of (visual) perception and cognition. The chapter then elaborates on the implications of these theoretical considerations with regards to operationalization, analysis, and interpretation of the eye‐tracking data. Finally, it discusses and critically assesses specific examples of studies employing eye tracking to illustrate how the method may be applied to media studies research.
Testing the direct, indirect, and moderated effects of childhood animal cruelty on future aggressive and non‐aggressive offending
Authors: Walters Glenn D.
Published: December 2013

The relationship between childhood cruelty toward animals and subsequent aggressive offending was explored in 1,336 (1,154 male, 182 female) participants from the 11‐wave Pathways to Desistance study (Mulvey, 2013). Aggressive and income offending at Waves 1 through 10 were regressed onto a dichotomous measure of prior involvement in animal cruelty and four control variables (age, race, sex, early onset behavior problems) assessed at Wave 0 (baseline). Results indicated that childhood animal cruelty was equally predictive of aggressive and non‐aggressive (income) offending, a finding inconsistent with the hypothesis that cruelty toward animals desensitizes a person to future interpersonal aggression or in some way prepares the individual for interpersonal violence toward humans. Whereas a significant sex by animal cruelty interaction was predicted, there was no evidence that sex or any of the other demographic variables included in this study (age, race) consistently moderated the animal cruelty–subsequent offending relationship. On the other hand, two cognitive‐personality measures (interpersonal hostility, callousness/unemotionality) were found to successfully mediate the animal cruelty–subsequent offending relationship. Outcomes from this study imply that a causal nexus—partially or fully mediated by hostility, callousness/unemotionality, and other cognitive‐personality variables—may exist between childhood animal cruelty and subsequent offending, although the effect is not specific to violence. Aggr. Behav. 40:238–249, 2014. © 2013 Wiley Periodicals, Inc.
Steric Protected and Illumination‐Activated Tumor Targeting Accessory for Endowing Drug‐Delivery Systems with Tumor Selectivity
Authors: Yuan Zhefan , Zhao Dan , Yi Xiaoqing , Zhuo Renxi , Li Feng
Published: December 2013

Here, an ABA‐typed polymer, octadecyl‐polyethylene glycol (biotin)‐(o‐nitrobenzyl)‐octadecyl ester (CPB‐p‐C) with an o‐nitrobenzyl group inserted between polyethylene glycol (PEG) and octadecyl ester is synthesized as an illumination‐activated tumor targeting accessory for micelle‐based drug carriers. The functional accessory can form a flower‐like structure with folded PEG segments in aqueous solution to hide targeting biotin ligands in the core of the mixed micelle. Thus the specific binding between biotin and avidin can be suppressed by the steric hindrance of PEG shell. Upon illumination, the flower‐like structure of CPB‐p‐C is destroyed due to the cleavage of the o‐nitrobenzyl group and the biotin moieties are exposed on the surface of the micelle through the stretching process of PEG segments, generating ligand‐receptor‐mediated targeted delivery. By confocal laser scanning microscopy and flow cytometry, the illumination‐activated, tumor‐targeting delivery is studied. The influence of the amount of functional accessory in the mixed micelle on the targeting property is investigated and the optimal amount of CPB‐p‐C to achieve less side effects and better illumination activated tumor targeting activity is identified. The observed properties of CPB‐p‐C qualify it as a promising functional accessory to endow traditional drug‐delivery systems with tumor selectivity.
High‐Throughput Fabrication of Au–Cu Nanoparticle Libraries by Combinatorial Sputtering in Ionic Liquids
Authors: König Dennis , Richter Kai , Siegel Alexander , Mudring Anja‐Verena , Ludwig Alfred
Published: December 2013

Materials libraries of binary alloy nanoparticles (NPs) are synthesized by combinatorial co‐sputter deposition of Cu and Au into the ionic liquid (IL) 1‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide ([C1C4im][Tf2N]), which is contained in a micromachined cavity array substrate. The resulting NPs and NP‐suspensions are investigated by transmission electron microscopy (TEM), X‐ray diffraction (XRD), UV‐Vis measurements (UV‐Vis), and attenuated total reflection Fourier transformed infrared (ATR‐FTIR) spectroscopy. Whereas the NPs can be directly observed in the IL using TEM, for XRD measurements the NP concentration is too low to lead to satisfactory results. Thus, a new NP isolation process involving capping agents is developed which enables separation of NPs from the IL without changing their size, morphology, composition, and state of aggregation. The results of the NP characterization show that next to the unary Cu and Au NPs, both stoichiometric and non‐stoichiometric Cu–Au NPs smaller than 7 nm can be readily obtained. Whereas the size and shape of the alloy NPs change with alloy composition, for a fixed composition the NPs have a small size distribution. The measured lattice constants of all capped NPs show unexpected increased values, which could be related to the NP/surfactant interactions.
Schaltbare Transparenz in hochgradig lumineszierenden dünnen Filmen der Raumnetzverbindung 3∞[EuIm2] abgeschieden durch Femto‐Laserablation
Authors: Fischer Dieter , Meyer Larissa V. , Jansen Martin , Müller‐Buschbaum Klaus
Published: December 2013

Hochgradig lumineszierende schaltbare dünne Filme der dichten Raumnetzverbindung ${{}_\infty ^3 \left[ {{\rm{Eu}}{\mathop{\rm Im}\nolimits} _2 } \right]}$ wurden mithilfe einer Laserablationstechnik mit Femtosekunden‐Laserpulsen erzeugt. Die Filme können dabei bezüglich Filmdicke und abgeschiedener Materialmenge genau eingestellt werden, wobei die Eigenschaften des Bulk‐Materials auf der Nanometerskala erhalten bleiben. Auf diese Weise können polykristalline Filme erzeugt werden, die zwischen transparent bei sichtbarem Licht und intransparent unter UV‐Licht durch die dadurch angeregte Emission des Materials geschaltet werden, und erweitern so das Konzept intelligenter Filme. Somit wird auch ein Zugang zu Beschichtungen für Raumnetzverbindungen und Koordinationspolymere mithilfe der neuen Femtosekunden‐PLD‐Methode vorgestellt.
Efficient Amide Bond Formation through a Rapid and Strong Activation of Carboxylic Acids in a Microflow Reactor
Authors: Fuse Shinichiro , Mifune Yuto , Takahashi Takashi
Published: December 2013

The development of highly efficient amide bond forming methods which are devoid of side reactions, including epimerization, is important, and such a method is described herein and is based on the concept of rapid and strong activation of carboxylic acids. Various carboxylic acids are rapidly (0.5 s) converted into highly active species, derived from the inexpensive and less‐toxic solid triphosgene, and then rapidly (4.3 s) reacted with various amines to afford the desired peptides in high yields (74 %–quant.) without significant epimerization (≤3 %). Our process can be carried out at ambient temperature, and only CO2 and HCl salts of diisopropylethyl amine are generated. In the long history of peptide synthesis, a significant number of active coupling reagents have been abandoned because the highly active electrophilic species generated are usually susceptible to side reactions such as epimerization. The concept presented herein should renew interest in the use of these reagents.
Conversion of a Disulfide Bond into a Thioacetal Group during Echinomycin Biosynthesis
Authors: Hotta Kinya , Keegan Ronan M. , Ranganathan Soumya , Fang Minyi , Bibby Jaclyn , Winn Martyn D. , Sato Michio , Lian Mingzhu , Watanabe Kenji , Rigden Daniel J. , Kim Chu‐Young
Published: December 2013

Echinomycin is a nonribosomal depsipeptide natural product with a range of interesting bioactivities that make it an important target for drug discovery and development. It contains a thioacetal bridge, a unique chemical motif derived from the disulfide bond of its precursor antibiotic triostin A by the action of an S‐adenosyl‐L‐methionine‐dependent methyltransferase, Ecm18. The crystal structure of Ecm18 in complex with its reaction products S‐adenosyl‐L‐homocysteine and echinomycin was determined at 1.50 Å resolution. Phasing was achieved using a new molecular replacement package called AMPLE, which automatically derives search models from structure predictions based on ab initio protein modelling. Structural analysis indicates that a combination of proximity effects, medium effects, and catalysis by strain drives the unique transformation of the disulfide bond into the thioacetal linkage.
Stereoselective Synthesis of Silicon‐Stereogenic Aminomethoxysilanes: Easy Access to Highly Enantiomerically Enriched Siloxanes
Authors: Bauer Jonathan O. , Strohmann Carsten
Published: December 2013

A route towards the synthesis of N,O‐functionalized silicon‐stereogenic organosilanes with excellent optical purities has been developed. Investigations into the stereoconvergence and configurational stability of an aminomethoxysilane suggest a kinetically controlled multistep substitution mechanism. Selective exchange of the Si‐N bond by a second Si‐O bond builds the basis for the controlled formation of chiral siloxane units with different oxygen‐containing functional groups. Subsequent reactions of the chiral aminomethoxysilanes with hydroxy groups support a general inversion mechanism at the asymmetrically substituted silicon atom of N,O‐functionalized organosilanes.
Electrical and EMI shielding characterization of multiwalled carbon nanotube/polystyrene composites
Authors: Sachdev Virendra Kumar , Bhattacharya Sudeshna , Patel Kamlesh , Sharma Surender Kumar , Mehra Navin Chand , Tandon Ram Pal
Published: December 2013

The electromagnetic interference (EMI) shielding mechanism of carbon nanotube (CNT)/polymer nanocomposites synthesized through a unique processing technique has been studied. As CNT/polymer nanocomposites evolve towards device applications, homogenous dispersion of CNTs has become a main objective to realize their full potential. In this work, dispersion of multi‐walled carbon nanotubes (MWCNTs) in polystyrene (PS) powder via dry state tumble mixing has been carried out. This involves the coating of the PS particles with the MWCNTs. Pellets were prepared by hot compression of resulted mixture. Conductivity behavior has shown that an extremely small mass fraction of 0.05 wt % MWCNTs in PS is good enough for percolation threshold. A detailed study of EMI shielding behavior of these composites is reported in addition to physical phenomena involved. The shielding effectiveness achieved is higher compared to solution mixing technique used by others. Decrease in hardness with increase in MWCNT content is little. Scanning electron microscope studies of these nanocomposites revealed a web/mesh like structure consisting of MWCNTs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40201.
Bicyclo[6.3.0]undecapentaenyl Anion: The Next Higher Homolog of the Indenyl Anion with Exceptionally Large Ion‐Pairing Effects on its Tropicity
Authors: Ozoe Hiroaki , Uno Yasutaka , Kitamura Chitoshi , Kurata Hiroyuki , Oda Masaji , Jones John W. , Scott Lawrence T. , Kawase Takeshi
Published: December 2013

The title anion 1 was generated as a fairly thermally stable species in tetrahydrofuran (THF) and dimethylsulfoxide (DMSO) by the action of several bases (sodium hydride, potassium hydride, lithium diisopropylamide, and lithium hexamethyldisilazide) with appropriate bicyclo[6.3.0]undecapentaenes. Variable‐temperature 1H NMR spectra of 1⋅Li+ in [D8]THF reveal that the anion exhibits exceptionally large ion‐pairing effects; proton chemical shifts vary by more than 1 ppm as a function of ion‐pairing conditions. Thus, anion 1, in a contact ion pair (Li+ at ambient temperature in THF), behaves as an aromatic cyclopentadienyl anion that is perturbed only slightly by the electronic effects of a paramagnetic cyclooctatetraene (COT), whereas 1 in a separated ion pair (Li+ at low temperatures in THF or at ambient temperature in DMSO) behaves as an overall paratropic species with a 12 π‐electron periphery. 13C NMR spectroscopy indicates no major skeletal rearrangement and only small variations of the electron density. The variable tropicity of 1 can be ascribed to small conformational changes of the molecule. In addition to its unusual, tunable tropicity, anion 1 can also serve as a versatile building block for the synthesis of cyclopentanoid conjugated systems fused to a fully unsaturated eight‐membered ring. A theoretical calculation predicts that the 10‐position of 1 should have the highest electron density. In agreement with this prediction, the reactions of 1 with electrophiles occur predominantly at the 10‐position. The corresponding ferrocene, two fulvenes, two diazo derivatives, and a COT‐fused azulene were obtained by the reactions of 1 with appropriate electrophiles.
Energy Transfer in Aminonaphthalimide‐Boron‐Dipyrromethene (BODIPY) Dyads upon One‐ and Two‐Photon Excitation: Applications for Cellular Imaging
Authors: Collado Daniel , Remón Patricia , Vida Yolanda , Najera Francisco , Sen Pratik , Pischel Uwe , Perez‐Inestrosa Ezequiel
Published: December 2013

Aminonaphthalimide–BODIPY energy transfer cassettes were found to show very fast (kEET≈1010–1011 s−1) and efficient BODIPY fluorescence sensitization. This was observed upon one‐ and two‐photon excitation, which extends the application range of the investigated bichromophoric dyads in terms of accessible excitation wavelengths. In comparison with the direct excitation of the BODIPY chromophore, the two‐photon absorption cross‐sectionδof the dyads is significantly incremented by the presence of the aminonaphthalimide donor [δ≈10 GM for the BODIPY versus 19–26 GM in the dyad atλexc=840 nm; 1 GM (Goeppert–Mayer unit)=10−50 cm4 s molecule−1photon−1]. The electronic decoupling of the donor and acceptor, which is a precondition for the energy transfer cassette concept, was demonstrated by time‐dependent density functional theory calculations. The applicability of the new probes in the one‐ and two‐photon excitation mode was demonstrated in a proof‐of‐principle approach in the fluorescence imaging of HeLa cells. To the best of our knowledge, this is the first demonstration of the merging of multiphoton excitation with the energy transfer cassette concept for a BODIPY‐containing dyad.
Der Nachweis der inneren Sicherheit von pfahlartigen Tragelementen im Boden
Authors: Alber Dirk
Published: December 2013

Dieser Aufsatz stellt ein Konzept zum Nachweis der inneren Tragfähigkeit pfahlartiger Tragelemente im Boden zur Diskussion. Diese Nachweise werden nach den Baustoffnormen geführt, während die Einwirkungen und Anforderungen den Regeln der Geotechnik unterliegen. Mit der Einführung der neuen Normengeneration ist diese Schnittstelle bei der Umsetzung in die Bemessungspraxis nicht gerade übersichtlicher geworden. Die einheitliche Handhabung des Nachweises der inneren Tragfähigkeit ist eine Notwendigkeit, besonders unter den Aspekten eines vergleichbaren Sicherheitsniveaus und des Wettbewerbs unterschiedlicher Herstellverfahren.

The proof of the internal bearing capacity of pile‐like elements in soil

This paper presents an approach for the proof of internal load bearing of pile‐like elements in the ground for discussion. These proofs are carried out according to the material standards, while the actions and requirements are subject to the rules of geotechnics. With the introduction of the new generation of standards this interface did not become clearer in practice. The uniform application of proofs of internal load bearing capacity is a necessity, especially in the aspects of a comparable level of safety and competition of different manufacturing technologies.
Bionisch‐inspirierte Faserverbundstrukturen
Authors: Waimer Frédéric , La Magna Riccardo , Reichert Steffen , Schwinn Tobias , Menges Achim , Knippers Jan
Published: December 2013

Das Interesse an freien Formen in der Architektur und im Industriedesign nimmt immer stärker zu. Für komplex geformte Strukturen sind faserbasierte Werkstoffe nahezu prädestiniert und bieten gegenüber klassischen Materialien im Bauwesen etliche Vorteile. Dennoch finden diese Materialien nur in seltenen Fällen Einzug in das Bauwesen. Die Abbildung von Geometrie und Materialität stellt dabei eine erhebliche Komplexität dar. Aus diesem Grund wurden von den Autoren neue bionische und multidisziplinäre Ansätze verfolgt, die es erlauben, das Potenzial des Materials für hocheffiziente Strukturen auszuschöpfen. Hierzu wurden ein angepasstes Verfahren zur Fertigung und neue Simulationswerkzeuge zur Planung für Architekten und Ingenieure entwickelt. Die entwickelten Methoden dienten als Grundlage eines im Sommer 2012 umgesetzten Versuchsbaus auf dem Campus der Universität Stuttgart und konnten dadurch erprobt und verifiziert werden. Die Strukturlogik des semitransparenten Pavillons wurde durch die räumliche Anordnung von Carbon‐ und Glasfasern definiert. Er hatte bei einer Spannweite von 8 m nur eine durchschnittliche Bauteildicke von 4, 6 mm und wog trotz seiner beachtlichen Größe weniger als 320 kg.

Bio‐inspired fibre composite structures – principles for fabrication and design

The request of free‐form surface generation strategies in architecture and industrial design is ever more increasing. For complex‐shaped structures, fibre‐based materials are often an obvious choice as they offer numerous advantages compared to traditional building materials and techniques. However, the usage of these materials in the construction field is still limited. Moreover, the design and simulation of fibre‐based materials is still a very challenging topic. For these reasons the authors developed an innovative, bionic‐inspired and multidisciplinary approach which allows the exploitation of the material potential to create highly efficient structures. Following this purpose, an integrated methodology for the simulation and manufacturing process was conceived for the architects and engineers. The developed methods were the basis for a prototype realized on the campus of the University of Stuttgart in the summer 2012, allowing the testing and proof of the proposed approach. The semi‐transparent pavilion spanned 8 m for a thickness of only 4.6 mm and weighed, despite its considerable size, less than 320 kg.
Cellular Loop: Ein Freischwinger, entwickelt nach dem Vorbild der Natur
Authors: Bernotat Anke
Published: December 2013

Beim ersten Blick könnte der Cellular Loop ein gewöhnlicher Freischwingerstuhl sein, wären da nicht die außergewöhnliche Zellstruktur und hätte er nicht die Form ähnlich der eines naht‐ und endlosen Möbiusbandes. Cellular Loop ist leicht, besitzt aber auch die Stabilität und Steifigkeit sowie die Elastizität, die man von einem Freischwingerstuhl erwartet. All diese Eigenschaften verdankt er der Übertragung von Konzepten aus der Natur auf seine Konstruktion und Form. Der Cellular Loop ist der erste Freischwinger, der im Rapid‐Manufacturing‐Verfahren hergestellt wurde. Ziel des Forschungsprojekts war die Entwicklung einer Fertigungstechnik für die Bauteileherstellung nach biologischen Konstruktions‐ und Strukturierungsprinzipien. Ein Freischwingerstuhl wurde als Demonstrator gewählt, weil Stühle im Design als die Königsdisziplin gelten und weil sich anhand eines Freischwingers Themen wie dynamische Kräfte, Elastizität und Materialminimierung gut untersuchen lassen. Dank der Übertragung von Vorbildern aus der Natur auf die additive Fertigungstechnik konnte ein leichter, aber auch stabiler Stuhl entstehen, dessen innere Baustruktur an unterschiedliche lokale Belastungen angepasst ist. Selektives Lasersintering ermöglichte ein schichtweises Wachstum der Bauteile nach bionischem Vorbild.

Cellular Loop: a chair based on biomimetics

At first sight, Cellular Loop might be mistaken for an ordinary cantilever chair – if it wasn't for its eye‐catching cell structure and its seamless, endless ribbon shape, similar to a moebius strip. The chair is lightweight, but also possesses the stiffness and stability as well as the elasticity one would expect from a cantilever chair. In order to achieve these characteristics, concepts from the natural world have been transferred to its construction and production method. Cellular Loop is also the first cantilever chair to be produced by Rapid Manufacturing. The aim of the research project was to develop a production method for components, inspired by biological construction principles and based on selective laser sintering. A cantilever chair was chosen as demonstration object, because chairs are considered the supreme discipline of design, but also because a cantilever chair is the perfect object for testing issues like dynamic strain, basic stiffness and minimal use of material.
Was macht die Architektin im Dschungel?
Authors: Gruber Petra
Published: December 2013

Der Artikel gibt eine Einführung in das Feld der Architekturbionik und präsentiert zwei Forschungsprojekte der Autorin, BioSkin und Biornametics, sowie die Entwicklung einer Methode des Einsatzes von Bionik als Innovationswerkzeug im Entwurf von Architektur.
The role of the Belgian engineer Paul Christophe on the development of reinforced concrete at the turn of the 20th century
Authors: Hellebois Armande , Espion Bernard
Published: December 2013

Paul Christophe (1870–1957) owes his fame to being the author of the book Le béton armé et ses applications, published first in 1899 and again in 1902. This publication is considered internationally as one of the first treatises on reinforced concrete which included detailed explanations of the various computation models in use at the turn of the 20th century. He concluded by proposing rational modelling of reinforced concrete based mainly on the previous work of Coignet & de Tedesco. Until the present research, the professional life of Christophe and the context of his publication were unknown. The discovery of large parts of the family archives has allowed clarification of the role of Paul Christophe in the theoretical development of reinforced concrete. Therefore the paper proposes first to draw up the biography of Paul Christophe, secondly to expose the ins and outs of the publication Le béton armé et ses applications and finally to explore his relations with others precursors of reinforced concrete such as the Austrian engineer Fritz von Emperger (1862–1942).

Die Rolle des belgischen Ingenieurs Paul Christophe auf die Entwicklung des Stahlbetonbaus zur Zeit der Jahrhundertwende

Paul Christophe (1870–1957) verdankt seinen Ruf dem Buch Le béton armé et ses applications, dessen Autor er war. Erstmals veröffentlicht wurde das Buch 1899, ein zweites Mal im Jahr 1902. Dieses Werk wird international als eine der ersten Abhandlungen über den Stahlbetonbau angesehen, die detaillierte Erläuterungen zu den verschiedenen, zur Zeit der Jahrhundertwende üblichen Berechnungsmodellen enthält. Der Autor schloss sein Buch mit der These, dass eine vernünftige Modellierung von Stahlbeton hauptsächlich auf die früheren Arbeiten von Coignet & de Tedesco zurückgeht. Bis dato war in der heutigen Forschung nichts über das Berufsleben von Christophe und den Zusammenhang mit seiner Veröffentlichung bekannt. Die Entdeckung von großen Teilen des Familienarchivs ermöglichte es nun zu klären, welche Rolle Paul Christophe im Bereich der theoretischen Entwicklung des Stahlbetonbaus inne hatte. Der Beitrag beginnt mit seiner Biographie. Anschließend wird gezeigt, welche Strömungen und Arbeiten Einfluss auf sein Buch Le béton armé et ses applications hatten und welchen Einfluss das Buch wiederum auf die Fachwelt hatte. Zuletzt werden seine Beziehungen zu anderen Vorreitern des Stahlbetonbaus, wie z.B. zum österreichischen Ingenieur Fritz von Emperger (1862–1942) erkundet.
Geordnete Verhältnisse. Mathematische Anschauungsmodelle im frühen 20. Jahrhundert
Authors: Sattelmacher Anja
Published: December 2013

Sorted Geometry. Mathematical Models on Display around 1900. By 1870, around the same time that mathematics turned away from intuitive Euclidean geometry, increasingly three‐dimensional geometric models were being incorporated into mathematical education at German universities and technical colleges. Connected to the increasingly specialized nature of engineering education as well as the growing demand for students in the fields of mechanics, kinematics, and statics in 1900, mathematics education at all levels called for the inclusion of more practical applications, often via the use of objects or images. Examining the works of the Darmstadt‐based professor of descriptive geometry Hermann Wiener (1857–1939), this essay discusses the various ways that three‐dimensional mathematical models were presented – both in combination with text and image, as well as part of an arranged series of objects in a showcase. As a mathematics professor, Wiener dedicated himself to the construction and use of models. He produced several series of wire models and sold them with an accompanying catalogue containing price lists and images. The models and the images were explicitly meant to serve as tools for enhancing students' intuitive mathematical knowledge. The visual knowledge thus generated was therefore cultivated not only through the research style of professors, but also as a result of the way in which things were presented and shown in a variety of non‐academic contexts around 1900, such as shop windows and exhibition showcases. This essay reveals that these various new ways of arranging mathematical models had an epistemic value that was deeply connected to visual concepts of that time period.
Expression of Eph receptor A10 is correlated with lymph node metastasis and stage progression in breast cancer patients
Authors: Nagano Kazuya , Kanasaki So‐ichiro , Yamashita Takuya , Maeda Yuka , Inoue Masaki , Higashisaka Kazuma , Yoshioka Yasuo , Abe Yasuhiro , Mukai Yohei , Kamada Haruhiko , Tsutsumi Yasuo , Tsunoda Shin‐ichi
Published: December 2013

Eph receptor A10 (EphA10) is a valuable breast cancer marker that is highly expressed in breast cancer tissues by comparison with normal breast tissues, as we previously reported. However, the role of EphA10 expression in breast cancer is not well understood. Here, we have analyzed the expression of EphA10 at the mRNA‐ and protein‐level in clinical breast cancer tissues and then evaluated the relationship with clinicopathological parameters for each sample. EphA10 mRNA expression was quantified by real‐time polymerase chain reaction using complimentary DNA (cDNA) samples derived from breast cancer patients. Lymph node (LN) metastasis and stage progression were significantly correlated with EphA10 expression at the mRNA level (P = 0.0091 and P = 0.034, respectively). Furthermore, immunohistochemistry (IHC) staining of breast cancer tissue microarrays (TMAs) revealed that EphA10 expression at the protein level was also associated with LN metastasis and stage progression (P = 0.016 and P = 0.011, respectively). These results indicate that EphA10 expression might play a role in tumor progression and metastasis. Our findings will help elucidate the role of EphA10 in clinical breast cancer progression.
Rosmarinic acid prevents lipid peroxidation and increase in acetylcholinesterase activity in brain of streptozotocin‐induced diabetic rats
Authors: Mushtaq Nadia , Schmatz Roberta , Pereira Luciane B. , Ahmad Mushtaq , Stefanello Naiara , Vieira Juliano M. , Abdalla Fátima , Rodrigues Marília V. , Baldissarelli Jucimara , Pelinson Luana Paula , Dalenogare Diéssica P. , Reichert Karine Paula , Dutra Eduardo M. , Mulinacci Nádia , Innocenti Marzia , Bellumori Maria , Morsch Vera Maria , Schetinger Maria Rosa
Published: December 2013

We investigated the efficacy of rosmarinic acid (RA) in preventing lipid peroxidation and increased activity of acetylcholinesterase (AChE) in the brain of streptozotocin‐induced diabetic rats. The animals were divided into six groups (n = 8): control, ethanol, RA 10 mg/kg, diabetic, diabetic/ethanol and diabetic/RA 10 mg/kg. After 21 days of treatment with RA, the cerebral structures (striatum, cortex and hippocampus) were removed for experimental assays. The results demonstrated that the treatment with RA (10 mg/kg) significantly reduced the level of lipid peroxidation in hippocampus (28%), cortex (38%) and striatum (47%) of diabetic rats when compared with the control. In addition, it was found that hyperglycaemia caused significant increased in the activity of AChE in hippocampus (58%), cortex (46%) and striatum (30%) in comparison with the control. On the other hand, the treatment with RA reversed this effect to the level of control after 3 weeks. In conclusion, the present findings showed that treatment with RA prevents the lipid peroxidation and consequently the increase in AChE activity in diabetic rats, demonstrating that this compound can modulate cholinergic neurotransmission and prevent damage oxidative in brain in the diabetic state. Thus, we can suggest that RA could be a promising compound in the complementary therapy in diabetes. Copyright © 2013 John Wiley & Sons, Ltd.
The Effect of Interfacial Design on the Electrochemical Detection of DNA and MicroRNA Using Methylene Blue at Low‐Density DNA Films
Authors: Tavallaie Roya , Darwish Nadim , Gebala Magdalena , Hibbert D. Brynn , Gooding J. Justin
Published: December 2013

Herein, we study the effect of interfacial design, specifically the orientation of a DNA probe strand, the length of the diluent and the type of target (DNA vs. microRNA), on the electrochemical response from methylene blue (MB) at low‐density DNA films. The probe DNA interfaces are formed from mixed self‐assembled monolayers of single‐stranded DNA (ss‐DNA) and a hydroxyl terminated alkanethiol diluents on gold surfaces. Variation in the current from the DNA–MB complex after hybridization with complementary and single adenine–cytosine mismatch DNA target is shown to depend on whether the 3′ or 5′ end is tethered to the electrode and the length of the diluent (6‐mercapto‐1‐hexanol vs. 9‐mercapto‐1‐nonanol). The sensors show better mismatch discrimination of single base pairs when both the duplexes are tethered from the 5′ end to the electrode and with a longer‐chain (9‐mercapto‐1‐nonanol) diluent. Of particular note is our demonstration that the DNA/microRNA duplex exhibits greater single adenine–cytosine mismatch discrimination when compared to the corresponding DNA/DNA duplex. This study contributes to the development of selective DNA and microRNA biosensors.
Lithium Insertion/Deinsertion Characteristics of Nanostructured Amorphous Tantalum Oxide Thin Films
Authors: Dang Hoang X. , Lin Yong‐Mao , Klavetter Kyle C. , Cell Trevor H. , Heller Adam , Mullins C. Buddie
Published: December 2013

Lithium uptake and release by pure, morphology‐controlled Ta2O5 films is studied. Porous nanocolumnar films, reactively e‐beam deposited at 70° versus normal, are rapidly lithiated and delithiated, withstanding volume‐change‐associated stresses. Their reversible gravimetric Coulombic capacities at 1 C, 2 C, 5 C, and 10 C rates are, respectively, 252, 225, 192, 168 mAh g−1. After 100 cycles at 1 C rate the films retain 96 % of their Coulombic capacity and 99 % of their Coulombic efficiency. The rapid lithiation/delithiation is attributed to formation of amorphous, Li+ permeable, nanoporous LiTaO3.
Iron‐Catalyzed Friedel–Crafts Benzylation with Benzyl TMS Ethers at Room Temperature
Authors: Sawama Yoshinari , Shishido Yuko , Kawajiri Takahiro , Goto Ryota , Monguchi Yasunari , Sajiki Hironao
Published: December 2013

Friedel–Crafts benzylations between unactivated arenes and benzyl alcohol derivatives are clean and straightforward processes to construct biologically useful di‐ and tri‐arylmethanes. We have established an efficient iron‐catalyzed Friedel–Crafts benzylation method at room temperature that uses benzyl TMS ethers as substrates, which are poorly reactive under common nucleophilic substitution conditions. The reaction seems to progress through iron‐catalyzed self‐condensation of the benzyl TMS ether to the corresponding dibenzylic ether. The use of excess arene relative to benzyl TMS ether produced mono‐benzylated arene (di‐ and tri‐arylmethane products), whereas the use of excess benzyl TMS ether versus arene provided bis‐benzylated arene (polyarylated products) in high yields and regioselectivities. In previous methods, the latter double Friedel–Crafts benzylations hardly proceed.
Self‐Assembly of Three‐Dimensional Supramolecular Polymers through Cooperative Tetrathiafulvalene Radical Cation Dimerization
Authors: Tian Jia , Ding Yu‐Di , Zhou Tian‐You , Zhang Kang‐Da , Zhao Xin , Wang Hui , Zhang Dan‐Wei , Liu Yi , Li Zhan‐Ting
Published: December 2013

The self‐assembly of a new type of three‐dimensional (3D) supramolecular polymers from tetrahedral monomers in both organic and aqueous media is described. We have designed and synthesized two tetraphenylmethane derivatives T1 and T2, both of which bear four tetrathiafulvalene (TTF) units. When the TTF units were oxidized to the radical cation TTF.+, their pre‐organized tetrahedral arrangement remarkably enhanced their intermolecular dimerization, leading to the formation of new 3D spherical supramolecular polymers. The structure of the supramolecular polymers has been inferred on the basis of UV/Vis absorption, electron paramagnetic resonance, cyclic voltammetry, and dynamic light scattering (DLS) analysis, as well as by comparing these properties with those of the self‐assembled structures of mono‐, di‐, and tritopic control compounds. DLS experiments revealed that the spherical supramolecular polymers had hydrodynamic diameters of 68 nm for T1 (75 μM) in acetonitrile and 105 nm for T2 (75 μM) in water/acetonitrile (1:1). The 3D spherical structures of the supramolecular polymers formed in different solvents were also supported by SEM and AFM experiments.
Base‐Catalyzed Tandem Michael/Dehydro‐Diels–Alder Reaction of α,α‐Dicyanoolefins with Electron‐Deficient 1,3‐Conjugated Enynes: A Facile Entry to Angularly Fused Polycycles
Authors: Zhang Mingrui , Zhang Junliang
Published: December 2013

Angularly fused carbocyclic frameworks and their heteroatom‐substituted analogues exist in many natural products that display a broad and interesting range of biological activities. Preparation of polycyclic products by cycloaddition reactions have been the long‐standing hot topic in the synthetic community. Dehydro‐Diels–Alder (DDA) reactions are one class of dehydropericyclic reactions that are derived conceptually by systematic removal of hydrogen atom pairs. A base‐promoted tandem Michael addition and DDA reaction of α,α‐dicyanoolefins with electron‐deficient 1,3‐conjugated enynes was realized in which a DDA reaction takes place between the arylalkynes and electron‐deficient tetrasubstituted olefin. The control experiments support the stepwise anionic reaction pathway rather than the concerted reaction pathway.
Blending Gelators to Tune Gel Structure and Probe Anion‐Induced Disassembly
Authors: Foster Jonathan A. , Edkins Robert M. , Cameron Gary J. , Colgin Neil , Fucke Katharina , Ridgeway Sam , Crawford Andrew G. , Marder Todd B. , Beeby Andrew , Cobb Steven L. , Steed Jonathan W.
Published: December 2013

Blending different low molecular weight gelators (LMWGs) provides a convenient route to tune the properties of a gel and incorporate functionalities such as fluorescence. Blending a series of gelators having a common bis‐urea motif, and functionalised with different amino acid‐derived end‐groups and differing length alkylene spacers is reported. Fluorescent gelators incorporating 1‐ and 2‐pyrenyl moieties provide a probe of the mixed systems alongside structural and morphological data from powder diffraction and electron microscopy. Characterisation of the individual gelators reveals that although the expected α‐urea tape motif is preserved, there is considerable variation in the gelation properties, molecular packing, fibre morphology and rheological behaviour. Mixing of the gelators revealed examples in which: 1) the gels formed separate, orthogonal networks maintaining their own packing and morphology, 2) the gels blended together into a single network, either adopting the packing and morphology of one gelator, or 3) a new structure not seen for either of the gelators individually was created. The strong binding of the urea functionalities to anions was exploited as a means of breaking down the gel structure, and the use of fluorescent gel blends provides new insights into anion‐mediated gel dissolution.
2,2,2‐Trifluoroacetophenone as an Organocatalyst for the Oxidation of Tertiary Amines and Azines to N‐Oxides
Authors: Limnios Dimitris , Kokotos Christoforos G.
Published: December 2013

A cheap, mild and environmentally friendly oxidation of tertiary amines and azines to the corresponding N‐oxides is reported by using polyfluoroalkyl ketones as efficient organocatalysts. 2,2,2‐Trifluoroacetophenone was identified as the optimum catalyst for the oxidation of aliphatic tertiary amines and azines. This oxidation is chemoselective and proceeds in high‐to‐quantitative yields utilizing 10 mol % of the catalyst and H2O2 as the oxidant.
ChemInform Abstract: First‐Principles Calculations of the Structural, Electronic, Optical and Elastic Properties of the New Phosphors, Na2ZrF6 and K2ZrF6.
Authors: Brik M. G. , Srivastava A. M.
Published: December 2013

Na2ZrF6 and K2ZrF6 are characterized using the plane‐wave based first‐principles calculations.
ChemInform Abstract: Clathrate Ba8Au16P30: The “Gold Standard” for Lattice Thermal Conductivity.
Authors: Fulmer James , Lebedev Oleg I. , Roddatis Vladimir V. , Kaseman Derrick C. , Sen Sabyasachi , Dolyniuk Juli‐Anna , Lee Kathleen , Olenev Andrei V. , Kovnier Kirill
Published: December 2013

The title compound is prepared by solid state reaction of stoichiometric amounts of the elements (glassy carbon crucible in evacuated silica ampules, 1073 K, 12 d).
ChemInform Abstract: Violet Blue Long‐Lasting Phosphorescence Properties of Mg‐Doped BaZrO3 and Its Ability to Assist Photocatalysis.
Authors: Ma Xinlong , Zhang Jiachi , Li Huihui , Duan Beicheng , Guo Linna , Que Meidan , Wang Yuhua
Published: December 2013

Mg‐doped BaZrO3 is prepared by solid state reaction of BaCO3, ZrO2, and (MgCO3)4Mg(OH)2 (alumina crucible, 1300—1400 °C, 6 h).
ChemInform Abstract: Pseudobinary Fe4Ti3S8 Compound with a NiAs‐Type Structure: Effect of Ti for Fe Substitution.
Authors: Ibrahim P. N. G. , Selezneva N. V. , Gubkin A. F. , Baranov N. V.
Published: December 2013

The title compound is prepared by solid state reaction of TiI4, S, and highly pure Fe (evacuated quartz tube; 1.
ChemInform Abstract: Synthesis Process Investigation and Electrochemical Performance Characterization of SrLi2Ti6O14 by ex situ XRD.
Authors: Liu Jianhong , Li Yanan , Wang Xingqin , Gao Yun , Wu Ningning , Wu Borong
Published: December 2013

The solid state synthesis of the title compound from SrCO3, Li2CO3, and TiO2 (air, 500—1000 °C, 8 h) is monitored by TG‐DTA and XRD.
ChemInform Abstract: Polyoxometalate {W18O56XO6} Clusters with Embedded Redox‐Active Main‐Group Templates as Localized Inner‐Cluster Radicals.
Authors: Vila‐Nadal Laia , Peuntinger Katrin , Busche Christoph , Yan Jun , Lueders Daniela , Long De‐Liang , Poblet Josep M. , Guldi Dirk M. , Cronin Leroy
Published: December 2013

Dawson‐like clusters {W18O56XO6} (X: I, Te) with localized redox active inner‐cluster templates are characterized by cyclic voltammetry, UV and EPR spectroscopy, and DFT calculations.
ChemInform Abstract: Asymmetric anti‐Aldol Addition of Achiral Ketones via Chiral N‐Amino Cyclic Carbamate Hydrazones.
Authors: Knight John D. , Coltart Don M.
Published: December 2013

The diastereoselective aldol addition reaction of chiral hydrazones (I) and aldehydes (II) followed by O‐benzylation of the resulting aldol adduct and subsequent removal of the chiral auxiliary affords desired O‐benzylated β‐hydroxyketones (V) in high overall yields.
ChemInform Abstract: Merging Organocatalysis with Transition Metal Catalysis and Using O2 as the Oxidant for Enantioselective C—H Functionalization of Aldehydes.
Authors: Zhao Yong‐Long , Wang Yao , Hu Xiu‐Qin , Xu Peng‐Fei
Published: December 2013

The enantioselective β‐functionalization of aldehydes (I) is successfully achieved by a Saegusa oxidation—Michael addition cascade reaction using palladium(II) acetate and the proline PRL as a catalytic system.
ChemInform Abstract: A Mild Lewis Acid Mediated Epoxy‐Ester to Bicyclic ortho Ester Rearrangement
Authors: Ahmed Awais , Christie Steven D. R. , Elsegood Mark R. J. , Pritchard Gareth J.
Published: December 2013

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