bluuebunny/crossref_metadata_2025 huggingface dataset:
Röntgenographische Untersuchung der Rekristallisation gemahlener Aluminium‐, Kupfer‐ und Nickelpulver 2. Mitteilung: Messungen mit dem Zählrohrgoniometer
Authors: Royen P. , Sterzel W.
Published: April 2015

Aluminium‐, Kupfer‐ und Nickelpulver wurden unter Einwirkung von Sauerstoff oder speziellen Mahlflüssigkeiten gemahlen. Die Rekristallisation der nach dem Mahlprozeß sehr stark verformten Metalle wird bei verschiedenen Glühtemperaturen röntgenographisch verfolgt. Aus den integralen Breiten der Röntgenlinien werden die mittleren Kristallitgrößen und Gitterverzerrungen berechnet. Außerdem werden die Metallpulver auf Stapelfehler und Texturen untersucht. Das Verhalten der gemahlenen Metallpulver wird untereinander und mit dem Verhalten der durch Pressen oder Walzen verformten Metalle verglichen. Es wird versucht, das besondere Verhalten mancher gemahlener Pulver bei der Rekristallisation mit Hilfe der Versetzungstheorie zu erklären.
Infrarotspektroskopische Untersuchungen an kristallinem Phosphorwasserstoff, Phosphoniumbromid und Phosphoniumchlorid
Authors: Heinemann A.
Published: April 2015

Das IR‐Spektrum von kristallinem Phosphorwasserstoff wird mitgeteilt und diskutiert. Für die PH3‐Moleküle werden die infrarotspektroskopisch nicht zu unterscheidenden site‐Symmetrien C3ν oder C3 festgestellt.

Die IR‐Spektren von kristallinem Phosphoniumbromid und Phosphoniumchlorid werden mitgeteilt und gedeutet. In den Kristallgittern dieser Salze haben die Phosphoniumionen die site‐Symmetrie Vd. Auf Grund ihrer Spektren wird für Phosphoniumbromid und Phosphoniumchlorid ein Gitter der Raumgruppe D4h7 vorgeschlagen.
Studies in Vibronic Spectroscopy: The Detailed Polarization of Absorption, Fluorescence, and Phosphorescence in Four Benzene Derivatives
Authors: Kalantar A. H. , Albrecht A. C.
Published: April 2015

Photoselection techniques are used to obtain the detailed polarizations of aniline, N,N‐dimethylaniline, p‐phenylenediamine, and N,N,n′,n′‐tetramethyl‐p‐phenylenediamine. The equivalence of the polarized photo‐oxidation and polarized emission techniques is established. The treatment of the polarization data with a calibrating factor (ε) is supported. Using ε, the components of the intrinsic molecular fractional transition probabilities (of absorption and emission) are calculated along the axes of the molecule and found to be wavelength dependent. That is, changing polarizations of absorption, fluorescence, and phosphorescence are found, indicating the presence of forbidden character in these transitions. In the first absorption band, the mixed polarization has to do only with the lowest singlet. The second absorption band appears to be of uniform (long axis) polarization. The polarization of fluorescence results exhibit less long axis character than is found in absorption and establish that out of plane character is absent in the lower singlet states. The polarization of the phosphorescence is mixed, mostly in plane, and makes possible a 3La assignment for the lowest triplet state. In the following paper, still more valuable information is presented, a consequence of the application of vibronic theory to the results.
Partialdipolmomente in Metallcarbonyl‐Derivaten
Authors: Strohmeier W. , Hellmann H.
Published: April 2015

Aus dem experimentell gemessenen Dipolmoment μexpD von Metallcarbonylderivaten wurden die Partialmomente μ (Ar‐M) der Bindung Aromat‐Zentralatom in XArM(CO)2D nach Richtung und Größe berechnet. Das Moment μ (Ar‐M) ist auf das Zentralatom gerichtet. Die Partialmomente der Donator‐Acceptor‐Bindung μ (D‐M) sind in M(CO)5D, XArM(CO)2D und C5H5M(CO)2D für den gleichen Typ des Acceptors und des Donators identisch. Sie wurden für die σ‐Bindung zwischen Metall und Stickstoffbasen in der Größe 4–5,9 (D) gefunden.

Für Donatoren mit der Fähigkeit zur Rückbindung ergaben sich kleinere Partialmomente μ (D‐M), da das Moment der dπ ‐ dπ‐, bzw. dπ – pπ‐Bindung der σ‐Bindung entgegengesetzt gerichtet ist. In den Nitril‐ und Isonitrilderivaten ist das Moment der σ‐Bindung kleiner als in den Derivaten der Stickstoff‐ und Phosphorverbindungen, was mit der geringen Stabilität dieser Derivate im Einklang steht.

In den disubstituierten Verbindungen ist μ (D‐M) von der gleichen Größe wie in den monosubstituierten.
Ultrarotspektroskopische Untersuchungen an primären aliphatischen Aminen 2. Mitteilung. Untersuchungen an den NH‐Valenzbanden der Methylaminhomologen und an den CH‐Valenzbanden von Methylamin
Authors: Wolff H. , Schmidt U.
Published: April 2015

Mit der in Mitt. 1 beschriebenen, aber verbesserten Technik werden beim Wechsel der Konzentration in Tetrachlorkohlenstoff und bei Variation der Temperatur zwischen —110 und + 190 °C untersucht:

Die NH‐Valenzbanden von Äthyl‐, n‐Propyl‐, n‐Hexyl‐ und n‐Decylamin,

die CH‐Valenzbanden von Methylamin.

Dabei werden die Banden der unverdünnten Amine teilweise auch an Verbindungen, die sich im festen Zustand befinden, untersucht.

Die NH‐Valenzbanden der Methylaminhomologen lassen mit der Änderung von Temperatur und Konzentration den auch bei Methylamin festgestellten Übergang zwischen Assoziat‐ und Monomerenbande erkennen. Der Wechsel belegt, daß auch die Homologen des Methylamins im flüssigen Zustand über Wasserstoffbrücken assoziiert sind. Jedoch sind die Assoziatbanden, wenn sie durch ihre Extinktionskoeffizienten dargestellt werden, bei den unverdünnten Homologen schwächer als bei unverdünntem Methylamin, und zwar um so schwacher, je größer die Kettenlänge des Amins ist; eine Erklärung hierfür ergibt sich daraus, daß mit zunehmender Zahl der CH2‐Gruppen die Konzentration der Aminogruppen innerhalb der Molekel verdünnt wird. Ferner ist bei den Homologen der Abstand der Assoziat‐ von der Monomerenbande kleiner als bei Methylamin, desgleichen die mittlere Assoziationsenergie, die sich größenordnungsmäßig für alle Amine zu 2000 cal/mol errechnet; beide Befunde entsprechen einander, da gemäß den bestehenden Vorstellungen beim kleineren Abstand von Assoziat‐ und Monomerenbande auch die Assoziationsenergie geringer ist. Für die Assoziatbanden erweist sich noch eine zweite Deutung als möglich; nach ihr kommt nur die Bande bei 3290 cm−1 der symmetrischen NH‐Valenzschwingung zu, die Bande bei 3200 cm‐l aber dem Oberton der NH‐Deformationsschwingung.

Die CH‐Valenzbanden von unverdünntem Methylamin und von hochkonzentrierten Lösungen der Verbindung in Tetrachlorkohlenstoff zeigen einen Intensitätswechsel zwischen der Bande der totalsymmetrischen CH‐Valenzschwingung und einer Bande, die bei 10‐15 cm−1 kleinerer Wellenzahl gelegen ist und erst bei tiefer Temperatur hervortritt. Dieser Intensitätswechsel scheint nur damit erklärbar, daß sich bei tiefen Temperaturen und hinreichend hohen Aminkonzentrationen in Methylamin neben NH…N‐ auch CH…N‐Brücken bilden. Wird davon ausgegangen, daß ein unbeanspruchtes einsames Elektronenpaar erforderlich ist, damit eine Wasserstoffbrücke entsteht, so setzt die Erklärung voraus, daß lineare oder verzweigte Assoziate vorhanden sind, oder selbst Monomere, wenn deren Auftreten in nennenswerter Menge bei den gegebenen Bedingungen noch möglich ist.
Untersuchungen an ionenbildenden phosphororganischen Verbindungen mit Ausnahme der Säuren und ihrer Derivate I. Leitfähigkeitsmessungen einiger Phosphoniumsalze in wäßriger Lösung
Authors: Schindlbauer Hellmuth , Höniger August
Published: April 2015

Es wurde erstmals das Leitfähigkeitsverhalten einiger Phosphoniumsalze (Tetramethyl‐, Trimethylphenyl‐, Dimethyldiphenyl‐, Methyltriphenyl‐ und Tetraphenylphosphoniumiodid) in Wasser untersucht. Wie aus der Konzentrationsabhängigkeit der Δc‐Werte zu ersehen ist, weicht das Verhalten aller Salze im Konzentrationsbereich zwischen 1 · 10−4 und etwa 3 · 10−3 Mol/l geringfügig von der Onsagerschen Grenzgeraden ab. Grenzleitfähigkeiten und Dissoziationskonstanten wurden nach der Methode von Fuoss und Kraus berechnet. Alle untersuchten Phosphoniumsalze sind starke Elektrolyte. In der Reihe von Tetramethyl‐ bis zum Tetraphenylphosphoniumiodid nehmen die Dissoziationskonstanten Kc(c = 0) zu.
Pulsradiolytische Untersuchung schneller Reaktionen von hydratisierten Elektronen, freien Radikalen und Ionen mit Tetranitromethan in wäßriger Lösung
Authors: Asmus K.‐D. , Henglein A. , Ebert M. , Keene J. P.
Published: April 2015

Die absoluten bimolekularen Geschwindigkeitskonstanten der Reaktionen des Tetranitromethans mit hydratisierten Elektronen, Wasserstoffatomen, verschiedenen Alkoholradikalen und mit den Ionen O2−, CH3COCH3− und Cu+ wurden bestimmt. Ferner wird ein Verfahren beschrieben, um Tetranitromethan als „Indikator”︁ für freie Radikale, die keine starke Lichtabsorption besitzen, zu verwenden. Auf diese Weise wurde die Reaktion OH + CH3OH → H2O + CH2OH untersucht.

Alle Reaktionen des Tetranitromethans sind sehr schnell und werden im wesentlichen durch die Diffusion der Reaktanden kontrolliert. Die Bildung des aci‐Nitroforms bei diesen Reaktionen wird auf die Übertragung eines Elektrons von dem Reaktionspartner auf das Tetranitromethan mit sofortiger Dissoziation des negativen Molekelions zurückgeführt. Freie neutrale Radikale übertragen etwa gleich schnell wie negative Radikalionen, während die Übertragung vom Cu+‐Ion langsamer geschieht.

Für die Reaktion des OH‐Radikals mit Methanol wurde eine überraschend hohe Geschwindigkeitskonstante von mehr als 3 · 109 Mol−1 1 sec−1 gefunden; auch dieser Prozeß scheint demnach weitgehend durch die Diffusion der Reaktionspartner bestimmt zu sein.
Über magnetische Kernresonanzspektren wäßriger Brenztraubensäurelösungen
Authors: Becker M.
Published: April 2015

Zur Aufklärung der Keto‐Enol‐Tautometrie der Brenztraubensäure, über welche in der Literatur wider‐sprechende Angaben zu finden sind, werden Kernresonanzspektren von der Brenztraubensäure und von Brenztraubensäure‐Wasser‐Mischungen aufgenommen, wobei als Eichsubstanz für die Linienintensität 1,4‐Dioxan verwendet wird. Die wasserfreie Brenztraubensäure besteht aus der Ketoform; ein etwaiger Enolgehalt liegt unter 2%. In wäßriger Lösung existiert ein ringförmiges Gleichgewicht zwischen der Ketoform, der durch Wasseraufnahme daraus entstehenden 2,2‐Dihydroxypropionsäure und den Anionen dieser Säuren. Die Dissoziationskonstante der Ketoform beträgt 0,86 · 10−2 mol · l−1, die der 2,2‐Dihydroxypropionsäure 2,5 · 10−4 mol · l−1. Aus der Temperaturabhängigkeit des Gleichgewichtes wird die Reaktions‐enthalpie und ‐entropie der Reaktion CH2COCOOH + H2O → CH3C(OH)2COOH ermittelt. Diese Reaktion wird durch Hydroniumionen katalysiert. In stark saurer Lösung läßt sich aus der Linienverbreiterung die Zerfallsgeschwindigkeitskonstante der 2,2‐Dihydroxypropionsäure bestimmen.
Die chemische Grundlage der Vererbung, der genetische Code
Authors: Ochoa Severo
Published: April 2015

In the cell the genetic information contained in a molecule of DNA is transferred to messenger RNA, which in turn acts as a template in the synthesis of protein. The nucleotide sequence in DNA is mirrored as a corresponding nucleotide sequence in the messenger RNA, the latter then determining the primary structure of the proteins (i.e. their amino acid sequence). In this way the language of the nucleic acids, which comprises four letters (the four nucleotide bases), is translated into that of the proteins, which comprises 20 letters (the 20 amino acids). It is supposed that each group of three consecutive nucleotide bases in the template RNA determines an amino acid. Hence the genetic code is a “triplet” code.

Polyribonucleotides, which can be synthesized readily from the ribonucleoside‐5′‐diphosphates with the help of the enzyme polynucleotide phosphorylase, can replace natural template RNA in a cell‐free system similar to that used in protein synthesis in which the amino acids are polymerised into polypeptide chains. Since the nature of the amino acids incorporated into the polypeptide chains depends on the base composition of the synthetic polynucleotide, it has been possible to discover the base compositions of a number of the triplets corresponding to the various amino acids. In the Escherichia coli system homopolynucleotides such as polyadenylic acid, polycytidylic acid and polyuridylic acid lead to the incorporation of lysine, proline and phenylalanine. Under these conditions polysine, polyproline and polyphenylalanine, respectively, are formed. Copolynucleotides, which contain two or more different nucleotide bases, direct several different amino acids into the polypeptide chain; for example, polypeptides made in the presence of polyadenylocytidylic acid contain lysine, isoleucine, asparagine, leucine, tyrosine and phenylalanine.

A correlation has been made between the base compositions of the individual synthetic polynucleotides which were added to the cell‐free E. coli system and the nature and quantity of the amino acids incorporated into the polypeptide chain. In this way the base compositions of 46 of the 68 possible triplets of template RNA, corresponding to the 20 amino acids, have so far been established. Probably all the “meaningful” triplets are not yet known. In some instances it is found that a certain amino acid is coded for by several different triplets; a code with such a property is termed a “degenerate” code. With few exceptions, the actual sequence of bases within a given triplet is not at present known; only the base composition has been determined. There are indications that the genetic code is universal or, in other words, that there is only one code for all forms of life.
Über die Codierung der Proteinstruktur in Gegenwart von Proflavin
Authors: Braunitzer G.
Published: April 2015

Es wird die Vermehrung eines einsträngigen DNS‐Phagens (fd) ohne und nach Zusatz von Proflavin untersucht. Verglichen werden die Kurven der Verteilung der biologischen Aktivität in der trägerfreien Elektrophorese der entsprechenden Ansätze, wodurch polare Änderungen im Hüllprotein erfaßt werden. Die Versuche wurden in zwei Serien, im Dunkel und in Gegenwart von Licht durchgeführt.
Hydration of Haemoglobin and its Reversible Oxygenation
Authors: Maričić S. , Pifat Greta , Pravdić V.
Published: April 2015

Electrical conductivity measurements were done on samples of solid bovine methaemoglobin of various hydration states. The energies of activation calculated from these data, are discussed with regard to Rosenberg's theory. The lowest value of the activation energy (observed at 35% hydration) corresponds to that of pure water.

Using spectrophotometric techniques the interaction of “chromohaemoglobin” (“anhydrohaemoglobin” after Haurowitz) with oxygen was followed in situ. The importance of the shell of hydration for the reversible oxygenation is discussed and a new hypothesis advanced.
Elektrophoretische Untersuchungen an Nukleohistonen
Authors: Olivera Baldomero M. , Huang Ru Chih , Davidson Norman
Published: April 2015

Es wird über elektrophoretische Untersuchungen an rekonstituierten Nukleohistonen, nativen Nukleohistonen und Chromatin in homogener wäßriger Lösung berichtet. Die Messungen wurden unter den folgenden Bedingungen ausgeführt: 0,01 M NaCl, 0,001 M Trispuffer, pH = 7,5, 0°C. Diese Nukleoproteine sind negativ geladen, aber ihre elektrophoretischen Beweglichkeiten sind geringer als die der nativen DNS. Die Beweglichkeiten rekonstituierter Nukleohistone nehmen mit steigendem Histon‐zu‐DNS‐Verhältnis ab. Für vollständig komplexgebundenes Nukleohiston (Molzahl DNS Phosphat ist gleich Molzahl basischer Aminosäuren im Histon) erhält man die folgenden Beweglichkeitswerte für Nukleohiston Ib, IIb, III und IV: 1,30,1,50,1,97, und 197 · 10−4 cm2 Volt−1 sec−1 (DNS = 2,17 · 10−4). Es wird nur eine teilweise Übereinstimmung der änderung der Beweglichkeiten mit der Anderung des sauren Aminosäuregehalts der Histone festgestellt. In einer Mischung von Nukleohiston IIb und DNS bewegen sich die beiden Komponenten unabhängig voneinander; in einer Mischung von Nukleohiston Ib und DNS findet man elektrophoretisch nur eine Komponente, deren Beweglichkeit zwischen denen der Ausgangskomponenten liegt. Aus verschiedenen Geweben der Erbse gewonnene Chromatine besitzen unterschiedliche Beweglichkeiten. Dieser Befund hängt möglicherweise mit ihrer biologischen Aktivität zusammen. Jedes einzelne Chromatin ist elektrophoretisch hinreichend homogen. Damit ist gezeigt, daß seine verschiedenen Komponenten alle zu einer elektrophoretischen Einheit zusammengebunden sind.
The Effects of Motor and Vocal Response Interruption and Redirection on Vocal Stereotypy and Appropriate Vocalizations
Authors: Shawler Lesley A. , Miguel Caio F.
Published: April 2015

Stereotypy has been defined as repetitive vocal or motor behaviors that are noncontextual with invariant topographies. One intervention to reduce vocal stereotypy and increase appropriate vocalizations is response interruption and redirection (RIRD). Previous research has suggested that RIRD's behavioral mechanism consists of punishment. The purpose of this study was to extend this research by comparing two procedures, namely, vocal and motor RIRD contingent upon the occurrence of vocal stereotypy and to evaluate concomitant increases in appropriate vocalizations. A multiple treatment reversal design was used to compare the effectiveness of both interventions on five children diagnosed with an Autism Spectrum Disorder. Results suggested that both demand topographies were equally effective in reducing vocal stereotypy and increasing appropriate vocalizations. This research replicates previous findings that have suggested that RIRD is a punishment procedure. Copyright © 2015 John Wiley & Sons, Ltd.
Biophysical probing of the binding properties of a Cu(II) complex with G‐quadruplex DNA: an experimental and computational study
Authors: Housaindokht Mohammad Reza , Verdian‐Doghaei Asma
Published: April 2015

Telomerase inhibition through G‐quadruplex stabilization by small molecules is of great interest as a novel anticancer therapeutic strategy. Here, we show that newly synthesized Cu‐complex binds to G‐quadruplex DNA and induces changes in its stability. This biophysical interaction was investigated in vitro using spectroscopic, voltammetric and computational techniques. The binding constant for this complex to G‐quadruplex using spectroscopic and electrochemical methods is in the order of 105. The binding stoichiometry was investigated using spectroscopic techniques and corresponded to a ratio of 1: 1. Fluorescence titration results reveal that Cu‐complex is quenched in the presence of G‐quadruplex DNA. Analysis of the fluorescence emission at different temperatures shows that ΔH° > 0, ΔS° > 0 and ΔG° < 0, and indicates that hydrophobic interactions played a major role in the binding processes. MD simulation results suggested that this ligand could stabilize the G‐quadruplex structure. An optimized docked model of the G‐quadruplex–ligand mixture confirmed the experimental results. Based on the results, we conclude that Cu‐complex as an anticancer candidate can bind and stabilize the G‐quadruplex DNA structure. Copyright © 2015 John Wiley & Sons, Ltd.
GreedExCol, A CSCL tool for experimenting with greedy algorithms
Authors: Debdi Ouafae , Paredes‐Velasco Maximiliano , Velázquez‐Iturbide J.Ángel
Published: April 2015

Costs and benefits are recurrent issues that concern all the computing areas, including computer and software engineering. Mastery of optimization algorithms is essential in these fields, but their didactics hardly has received any attention. To fill this gap, the interactive system GreedEx was designed to support the active learning of greedy algorithms by means of experimentation. In this article we describe GreedExCol, a collaborative extension of GreedEx that complements its experimental phase with a discussion phase held by the students in each team. The contributions of the article are threefold. Firstly, we present GreedExCol, a CSCL system aimed at supporting collaborative discussion on experimental results of optimality for greedy algorithms. Secondly, GreedExCol was evaluated with respect to educational effectiveness, obtaining statistically significant improvements of the collaborative, experimental approach over an individual, experimental approach without the support of GreedExCol. Thirdly, GreedExCol was evaluated in the same two groups with respect to motivation, obtaining a statistically significant increase of implicit motivation for students in the experimental group. Overall, we present a medium‐term effort for developing an innovative learning system and a comprehensive evaluation of its impact over the students. © 2015 Wiley Periodicals, Inc. Comput. Appl. Eng. Educ. Comput Appl Eng Educ 23:790–804, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21655
Comparative methylome analysis in solid tumors reveals aberrant methylation at chromosome 6p in nasopharyngeal carcinoma
Authors: Dai Wei , Cheung Arthur Kwok Leung , Ko Josephine Mun Yee , Cheng Yue , Zheng Hong , Ngan Roger Kai Cheong , Ng Wai Tong , Lee Anne Wing Mui , Yau Chun Chung , Lee Victor Ho Fu , Lung Maria Li
Published: April 2015

Altered patterns of DNA methylation are key features of cancer. Nasopharyngeal carcinoma (NPC) has the highest incidence in Southern China. Aberrant methylation at the promoter region of tumor suppressors is frequently reported in NPC; however, genome‐wide methylation changes have not been comprehensively investigated. Therefore, we systematically analyzed methylome data in 25 primary NPC tumors and nontumor counterparts using a high‐throughput approach with the Illumina HumanMethylation450 BeadChip. Comparatively, we examined the methylome data of 11 types of solid tumors collected by The Cancer Genome Atlas (TCGA). In NPC, the hypermethylation pattern was more dominant than hypomethylation and the majority of de novo methylated loci were within or close to CpG islands in tumors. The comparative methylome analysis reveals hypermethylation at chromosome 6p21.3 frequently occurred in NPC (false discovery rate; FDR=1.33 × 10−9), but was less obvious in other types of solid tumors except for prostate and Epstein–Barr virus (EBV)‐positive gastric cancer (FDR<10−3). Bisulfite pyrosequencing results further confirmed the aberrant methylation at 6p in an additional patient cohort. Evident enrichment of the repressive mark H3K27me3 and active mark H3K4me3 derived from human embryonic stem cells were found at these regions, indicating both DNA methylation and histone modification function together, leading to epigenetic deregulation in NPC. Our study highlights the importance of epigenetic deregulation in NPC. Polycomb Complex 2 (PRC2), responsible for H3K27 trimethylation, is a promising therapeutic target. A key genomic region on 6p with aberrant methylation was identified. This region contains several important genes having potential use as biomarkers for NPC detection.
Efficient Biosynthesis of Ethyl (R)‐3‐Hydroxyglutarate through a One‐Pot Bienzymatic Cascade of Halohydrin Dehalogenase and Nitrilase
Authors: Yao Peiyuan , Wang Lei , Yuan Jing , Cheng Lihua , Jia Rongrong , Xie Meixian , Feng Jinhui , Wang Min , Wu Qiaqing , Zhu Dunming
Published: April 2015

The front cover artwork for Issue 09/2015 is provided by the Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences (P.R. China), the Tianjin University of Science & Technology (P.R. China), and Hebei Chengxin Co., Ltd (P.R. China). The image shows two one‐pot processes for the bienzymatic synthesis of ethyl (R)‐3‐hydroxyglutarate (EHG), a key intermediate for the synthesis of rosuvastatin, from ethyl (S)‐4‐chloro‐3‐hydroxybutyrate (ECHB). See the Full Paper itself at http://dx.doi.org/10.1002/cctc.201500061.
Anforderungen der zukunftsorientierten Spezialchemie an die angewandte Reaktionstechnik
Authors: Wachsen Olaf , Bacher Vanessa , Geisbauer Andreas , Appel Jörg , Niebuhr Verena , Lade Oliver
Published: April 2015

Die Menschheit steht gegenwärtig vor enormen ökonomischen, ökologischen und sozialen Herausforderungen. Die Spezialchemie leistet mit ihren bereits langjährig etablierten und mit innovativen Produkten einen entscheidenden Beitrag zur Bewältigung dieser Megatrends. Daraus abgeleitet ergeben sich die zukünftigen Anforderungen an die angewandte chemische Reaktionstechnik. Sowohl bewährte als auch neue Methoden werden benötigt, um im interdisziplinären Umfeld zwischen Chemie, Physik, Biologie und Ingenieurwissenschaften erfolgreiche Beiträge liefern zu können.
Input variable selection for an inferential predictor using the retrospective Taguchi method
Authors: Rahman M. Musfiqur , Imtiaz Syed Ahmad , Hawboldt Kelly , Zhang Yan
Published: April 2015

A systematic method based on Taguchi's experimental design approach is proposed for selecting input variables for an inferential predictor. Several implementation difficulties arising from dynamic variation and correlation among process variables are addressed. The predictor is developed using support vector regression (SVR) in order to capture the nonlinearity in the process. The prediction performance of the proposed Taguchi‐SVR is compared with the existing variable importance in projection (VIP)'SVR method. The industrial case study clearly indicates that the proposed methodology can be a valuable tool for process variable selection and it can improve the prediction performance of the inferential predictor.
5‐year follow‐up of a randomized controlled trial of immediate versus delayed zoledronic acid for the prevention of bone loss in postmenopausal women with breast cancer starting letrozole after tamoxifen: N03CC (Alliance) trial
Authors: Wagner‐Johnston Nina D. , Sloan Jeff A. , Liu Heshan , Kearns Ann E. , Hines Stephanie L. , Puttabasavaiah Suneetha , Dakhil Shaker R. , Lafky Jacqueline M. , Perez Edith A. , Loprinzi Charles L.
Published: April 2015

BACKGROUND

Postmenopausal women with breast cancer receiving aromatase inhibitors are at an increased risk of bone loss. The current study was undertaken to determine whether upfront versus delayed treatment with zoledronic acid (ZA) impacted bone loss. This report described the 5‐year follow‐up results.

METHODS

A total of 551 postmenopausal women with breast cancer who completed tamoxifen treatment and were undergoing daily letrozole treatment were randomized to either upfront (274 patients) or delayed (277 patients) ZA at a dose of 4 mg intravenously every 6 months. In the patients on the delayed treatment arm, ZA was initiated for a postbaseline bone mineral density T‐score of <‐2.0 or fracture.

RESULTS

The incidence of a 5% decrease in the total lumbar spine bone mineral density at 5 years was 10.2% in the upfront treatment arm versus 41.2% in the delayed treatment arm (P<.0001). A total of 41 patients in the delayed treatment arm were eventually started on ZA. With the exception of increased NCI Common Toxicity Criteria (CTC) grade 1/2 elevated creatinine and fever in the patients treated on the upfront arm and cerebrovascular ischemia among those in the delayed treatment arm, there were no significant differences observed between arms with respect to the most common adverse events of arthralgia and back pain. Osteoporosis occurred less frequently in the upfront treatment arm (2 vs 8 cumulative cases), although this difference was not found to be statistically significant. Bone fractures occurred in 24 patients in the upfront treatment arm versus 25 patients in the delayed treatment arm.

CONCLUSIONS

Immediate treatment with ZA prevented bone loss compared with delayed treatment in postmenopausal women receiving letrozole and these differences were maintained at 5 years. The incidence of osteoporosis or fractures was not found to be significantly different between treatment arms. Cancer 2015;121:2537–2543. © 2015 American Cancer Society.
Vacancy‐Free Prussian Blue Nanocrystals with High Capacity and Superior Cyclability for Aqueous Sodium‐Ion Batteries
Authors: Wu Xianyong , Sun Mengying , Guo Simin , Qian Jiangfeng , Liu Yong , Cao Yuliang , Ai Xinping , Yang Hanxi
Published: April 2015

Aqueous Na‐ion batteries have the competitive advantages of being low costing and possessing inherent safety, and they are particularly suitable for large‐scale energy‐storage applications. However, the development of this new battery system is hindered by the lack of suitable Na hosts with sufficiently high capacity and cycle life. Herein, we report vacancy‐free Na2CoFe(CN)6 nanocubes synthesized by a controlled crystallization reaction and reveal their use as a new aqueous cathode with reversible Na‐storage behavior. Owing to its perfect lattice framework with two redox‐active sites, this material exhibits a high reversible capacity of 130 mA h g−1, a strong rate capability at 20 C, and superior cyclability with 90 % capacity retention over 800 cycles, all of which indicate that this material may possibly serve as a high‐performance and long‐life cathode for aqueous Na‐ion batteries. Also, the synthetic strategy described in this work may be extended to a wide range of Prussian blue compounds for the fabrication of well‐shaped nanocubes with few defects for energy storage, catalysis, and other applications.
Kitchen‐Inspired Nanochemistry: Dispersion, Exfoliation, and Hybridization of Functional MoS2 Nanosheets Using Culinary Hydrocolloids
Authors: Ravula Sudhir , Essner Jeremy B. , Baker Gary A.
Published: April 2015

As a two‐dimensional material, molybdenum disulfide (MoS2) has drawn wide attention due to its fascinating properties and exciting application prospects. However, in order to access these properties, which lie within single‐ or few‐layer nanosheets, the inter‐sheet van der Waals interactions within the bulk material must be adequately disrupted to exfoliate MoS2 to atomic thicknesses. The hitch with most current exfoliation methods, though, is that they employ expensive, exotic, or environmentally incompatible methods that suffer poor scalability and poor reproducibility, producing weakly stabilized sheets that retro‐aggregate. These pitfalls render many current approaches unsuitable for the development of large‐scale devices and nanocomposites, thereby making cheaper, more benign alternatives highly sought after. Herein, we present the sonication‐assisted aqueous phase exfoliation of bulk MoS2 into dispersed single‐ or few‐layer nanosheets using popular culinary hydrocolloids, including guar gum (GG), tannic acid (TA), and xanthan gum (XG). These green agents are commercially available, inexpensive, and environmentally friendly substances and act as good dispersing and exfoliating agents. Under optimized exfoliation conditions, dispersed solution concentrations of 0.24, 0.15, and 0.06 mg mL−1 were achieved for MoS2‐GG, MoS2‐TA, and MoS2‐XG, respectively. In addition, the sterically stabilized nanosheets were successfully decorated with gold nanoparticles via an in situ reduction by the hydrocolloids to yield plasmonic nanocomposites exhibiting excellent catalytic activity in 4‐nitrophenol reduction.
Towards Shape Control of Metal Oxide Nanocrystals in Confined Molten Media
Authors: Chen Dennis P. , Fu Jie , Skrabalak Sara E.
Published: April 2015

Spray synthesis is a robust route to compositionally complex materials as fine powders; however, the solid‐state synthetic conditions in most cases limit access to discrete nanoparticles with defined structural features. Yet, by maintaining a dynamic droplet phase through integration of molten salt chemistry, product formation can proceed in manners similar to lower temperature solution routes to nanomaterials. This Focus Review connects concepts from classical nucleation theory and molten salt chemistry to provide a framework for nanocrystal formation via aerosol‐assisted molten salt synthesis (AMSS). Examples of metal oxide nanocrystal formation by AMSS are surveyed and highlight how the spatial and temporal confinement of aerosol droplets limits crystal growth in molten media. Ultimately, we strive to provide practical guidelines, not limited to AMSS, towards the synthesis of compositionally complex materials as shape‐defined nanocrystals.
Minimal Graphic Functions on Manifolds of Nonnegative Ricci Curvature
Authors: Ding Qi , Jost Jürgen , Xin Yuanlong
Published: April 2015

We study minimal graphic functions on complete Riemannian manifolds ∑ with nonnegative Ricci curvature, euclidean volume growth, and quadratic curvature decay. We derive global bounds for the gradients for minimal graphic functions of linear growth only on one side. Then we can obtain a Liouville‐type theorem with such growth via splitting for tangent cones of ∑ at infinity. When, in contrast, we do not impose any growth restrictions for minimal graphic functions, we also obtain a Liouville‐type theorem under a certain nonradial Ricci curvature decay condition on ∑. In particular, the borderline for the Ricci curvature decay is sharp by our example in the last section. © 2015 Wiley Periodicals, Inc.
K‐Stability and Kähler‐Einstein Metrics
Authors: Tian Gang
Published: April 2015

We prove that if a Fano manifold M is K‐stable, then it admits a Kähler‐Einstein metric. It affirms a longstanding conjecture for Fano manifolds. © 2015 Wiley Periodicals, Inc.
Population pharmacokinetic modeling of motesanib and its active metabolite, M4, in cancer patients
Authors: Gosselin Nathalie H. , Mouksassi Mohamad‐Samer , Lu Jian‐Feng , Hsu Cheng‐Pang
Published: April 2015

Motesanib is a small molecule and potent multikinase inhibitor with antiangiogenic and antitumor activity. Population pharmacokinetic (POPPK) modeling of motesanib and M4, an active metabolite, was performed to assess sources of variability in cancer patients. The analysis included data collected from 451 patients from 8 clinical trials with oral doses of motesanib ranging from 25 to 175 mg, either once daily or twice daily. The POPPK analyses were performed using nonlinear mixed‐effect models with a sequential approach. Covariate effects of demographics and other baseline characteristics were assessed with stepwise covariate modeling. A 2‐compartment model with food effect on absorption parameters fitted the PK data of motesanib well. The effects albumin and sex on apparent clearance (CL/F) of motesanib were statistically significant. The albumin effect was more important but remained below a 25% difference. A 1‐compartment model fitted PK data of M4 well. Effects of race (Asian vs non‐Asian) and dosing frequency were identified as statistically significant covariates on the CL/F of M4. The maximum effect of albumin would result in less than 25% change in motesanib CL/F and as such would not warrant any dosing adjustment. However, faster elimination of M4 in Asian patients requires further investigation.
Parallel sphere detector algorithm providing optimal MIMO detection on massively parallel architectures
Authors: Józsa Csaba M. , Kolumbán Géza , Vidal Antonio M. , Martínez‐Zaldívar Francisco J. , González Alberto
Published: April 2015

Multiple‐input multiple‐output (MIMO) systems have attracted considerable attention in wireless communications because they offer a significant increase in data throughput and link coverage without additional bandwidth requirement or increased transmit power. The price that has to be paid is the increased complexity of hardware components and algorithms. The sphere detector (SD) algorithm solves the problem of maximum likelihood (ML) detection for MIMO channels by significantly reducing the search space of possible solutions. The main drawback of the SD algorithm is in its sequential nature, consequently, running it on massively parallel architectures (MPAs) is very inefficient. In order to overcome the drawbacks of the SD algorithm, a new parallel sphere detector (PSD) algorithm is proposed. It implements a novel hybrid tree search method, where the algorithm parallelism is assured by the efficient combination of depth‐first search and breadth‐first search algorithms. A path metric‐based parallel sorting is employed at each intermediate stage. The PSD algorithm is able to adjust its memory requirements and extent of parallelism to fit a wide range of parallel architectures. Mapping details for MPAs are proposed by giving the details of thread dependent, highly parallel building blocks of the algorithm. Based on the building blocks proposed, a mapping to general‐purpose graphics processing unit is provided, and its performance is evaluated. In order to achieve high‐throughput, several levels of parallelism are introduced, and different scheduling strategies are considered. Copyright © 2015 John Wiley & Sons, Ltd.
Elder Mediation: What's in a Name?
Authors: Barry Lise
Published: April 2015

As an emerging discipline, specialist elder mediation has been characterized by diversity, with developments in the field often driven by the needs of family members, caregivers, health professionals, and the legal fraternity rather than the consumer demands of the elderly themselves. In this environment, there is a danger that the voice of elders will be forgotten or marginalized. At its best, elder mediation can play an important role in giving voice to older participants and ensuring that their will and preferences take center stage. At worst, elder mediation could play a role in increasing the vulnerability of older people by providing a forum that gives only lip‐service to their rights. The author urges the elder mediation movement to ask, “What's in a name?” and suggests that the term elder mediation is most properly considered an umbrella term referring to the specialist knowledge of the mediators and the obligation to accommodate the participation of older people in decisions that affect them. The author argues that mediators should be specific about the process they are providing under that banner and that one way this can be achieved is through careful naming of the practice and procedures.
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Authors: Rinkevich Yuval , Maan Zeshaan N. , Walmsley Graham G. , Sen Subhro K.
Published: April 2015

Background The regrowth of amputated appendage extremities and the distal tips of digits represent models of tissue regeneration in multiple vertebrate taxa. In humans, digit tip injuries, including traumatic amputation and crush injuries, are among the most common type of injury to the human hand. Despite clinical reports demonstrating natural regeneration of appendages in lower vertebrates and human digits, current treatment options are suboptimal, and are complicated by the anatomical complexities and functions of the different tissues within the digits. Results: In light of these challenges, we focus on recent advancements in understanding appendage regeneration from model organisms. We pay special attention to the cellular programs underlying appendage regeneration, where cumulative data from salamanders, fish, frogs, and mice indicate that regeneration occurs by the actions of lineage‐restricted precursors. We focus on pathologic states and the interdependency that exists, in both humans and animal models, between the nail organ and the peripheral nerves for successful regeneration. Conclusions: The increased understanding of regeneration in animal models may open new opportunities for basic and translational research aimed at understanding the mechanisms that support limb regeneration, as well as amelioration of limb abnormalities and pathologies. Developmental Dynamics 244:641–650, 2015. © 2015 Wiley Periodicals, Inc.
Skeletal muscle weakness is related to insulin resistance in patients with chronic heart failure
Authors: Doehner Wolfram , Turhan Guelistan , Leyva Francisco , Rauchhaus Mathias , Sandek Anja , Jankowska Ewa A , von Haehling Stephan , Anker Stefan D
Published: April 2015

Background

Chronic heart failure (CHF) is associated with insulin resistance, indicating impairment in the control of energy metabolism. Insulin resistance in CHF relates to symptomatic status and independently predicts poor prognosis. We sought to determine whether insulin sensitivity is related to skeletal muscle strength in patients with CHF, taking into account muscle size and perfusion.

Methods

Quadriceps muscle size (square centimetre cross‐sectional area at mid‐femur level, computed tomography), isometric quadriceps muscle strength [absolute (in N) and strength per unit muscle area (N/cm2)], resting‐leg blood flow (plethysmography) and maximal oxygen consumption (treadmill exercise test) were measured in 33 patients with CHF (left ventricular ejection fraction 28 ± 3.2%, mean ± Standard Error of the mean (SEM)) and 20 healthy controls. Insulin sensitivity was assessed by intravenous glucose tolerance tests and minimal modelling analysis.

Results

Right quadriceps strength (−27.0%, P < 0.0001), strength per muscle area (−18.0%, P < 0.003) and insulin sensitivity (−64.2%, P < 0.001) were lower in patients with CHF. The correlation between insulin sensitivity and absolute muscle strength was significant in the CHF group (r = 0.54, P = 0.001) and borderline in controls (r = 0.47, P = 0.06). This association remained significant between insulin sensitivity and strength per muscle area (CHF: r = 0.52, P < 0.01; controls: r = 0.62, P < 0.05). In stepwise regression analyses in CHF, only insulin sensitivity emerged as a predictor of strength per unit area of muscle [standardized coefficient (SC) = 0.45, P = 0.006; diuretic dose, SC = −0.31, P = 0.051; R2 = 0.37, P = 0.001], while age, left ventricular ejection fraction, maximal oxygen consumption, fasting glucose and insulin and blood flow were excluded. In controls, only insulin sensitivity remained in the final regression model (SC = 0.62, P = 0.004; R2 = 0.39, P = 0.004).

Conclusions

The myofibril contractile function of the quadriceps, i.e. functional quality of skeletal muscle, is strongly related to insulin sensitivity in patients with CHF and in healthy controls, independently of muscle size. Therapies aimed at improving insulin sensitivity in patients with CHF may clarify whether this relationship is causal.
Global variation in clinical profile, management, and post‐discharge outcomes among patients hospitalized for worsening chronic heart failure: findings from the ASTRONAUT trial
Authors: Greene Stephen J. , Fonarow Gregg C. , Solomon Scott D. , Subacius Haris , Maggioni Aldo P. , Böhm Michael , Lewis Eldrin F. , Zannad Faiez , Gheorghiade Mihai ,   for the ASTRONAUT Investigators and Coordinators
Published: April 2015

Aims

This study sought to investigate regional variation in clinical characteristics, therapy utilization, and post‐discharge outcomes among patients hospitalized for heart failure (HHF) enrolled in the multinational ASTRONAUT (Aliskiren Trial on Acute Heart Failure Outcomes) trial.

Methods and results

The ASTRONAUT trial randomized 1615 HHF patients with ejection fraction ≤40% to aliskiren or placebo. Enrolled patients were from Eastern Europe (n = 495, 30.7%), Asia/Pacific (n = 439, 27.2%), Western Europe (n = 395, 24.5%), Latin America (n = 163, 10.1%), and North America (n = 123, 7.6%). Marked differences were seen across geographic regions in terms of baseline demographics, vital signs, laboratory tests, co‐morbidity burden, and use of guideline‐recommended therapies. All‐cause death at 12 months ranged from 7.3% in North America to 26.7% in Asia/Pacific, with differences largely driven by sudden cardiac death. Rates of repeat HHF at 12 months ranged from 22.7% in Latin America to 43.9% in North America. After adjustment for patient characteristics, region was an independent predictor of death at 12 months, with highest risk in Asia/Pacific (hazard ratio 3.04, 95% confidence interval 1.47–6.29, compared with North America) and lowest risk in North America and Western Europe. There was no association between region and the composite of cardiovascular mortality or HHF.

Conclusion

For patients enrolled in this HHF trial, baseline characteristics and risk of death differed markedly by geographic region. Rates of death and repeat HHF demonstrated a general inverse relationship. Global differences in patient characteristics and outcomes should be accounted for when designing future HHF clinical trials.
Slp‐76 is a critical determinant of NK‐cell mediated recognition of missing‐self targets
Authors: Lampe Kristin , Endale Mehari , Cashman Siobhan , Fang Hao , Mattner Jochen , Hildeman David , Hoebe Kasper
Published: April 2015

Absence of MHC class I expression is an important mechanism by which NK cells recognize a variety of target cells, yet the pathways underlying “missing‐self” recognition, including the involvement of activating receptors, remain poorly understood. Using ethyl‐N‐nitrosourea mutagenesis in mice, we identified a germline mutant, designated Ace, with a marked defect in NK cell mediated recognition and elimination of “missing‐self” targets. The causative mutation was linked to chromosome 11 and identified as a missense mutation (Thr428Ile) in the SH2 domain of Slp‐76—a critical adapter molecule downstream of ITAM‐containing surface receptors. The Slp‐76 Ace mutation behaved as a hypomorphic allele—while no major defects were observed in conventional T‐cell development/function, a marked defect in NK cell mediated elimination of β2‐microglobulin (β2M) deficient target cells was observed. Further studies revealed Slp‐76 to control NK‐cell receptor expression and maturation; however, activation of Slp‐76ace/ace NK cells through ITAM‐containing NK‐cell receptors or allogeneic/tumor target cells appeared largely unaffected. Imagestream analysis of the NK‐β2M−/− target cell synapse revealed a specific defect in actin recruitment to the conjugate synapse in Slp‐76ace/ace NK cells. Overall these studies establish Slp‐76 as a critical determinant of NK‐cell development and NK cell mediated elimination of missing‐self target cells in mice.
Identification With All Humanity: The role of self‐definition and self‐investment
Authors: Reese Gerhard , Proch Jutta , Finn Christine
Published: April 2015

Identification With All Humanity (IWAH) relates to higher levels of concern and supportive behavior toward the disadvantaged, stronger endorsement of human rights, and stronger responses in favor of global harmony. So far, IWAH has been conceptualized as a one‐dimensional construct describing the degree with which one identifies with all humans as a superordinate ingroup. However, recent group identification models suggest a multi‐dimensional model to provide a more differentiated approach toward the understanding of the highest level of social identification. Using principal axis (Study 1) and confirmatory (Study 2) factor analyses, we suggest that IWAH sub‐divides into two dimensions—global self‐definition and global self‐investment. Study 2 revealed that global self‐investment was a stronger predictor for both convergent measures (e.g., social dominance orientation and authoritarianism) and behavioral intentions than global self‐definition. Finally, in Study 3, we manipulated IWAH to test its causal effect on donation behavior. Participants in the experimental condition, compared with the control condition, showed higher global self‐investment, which in turn predicted greater giving to global charity. These findings suggest that two dimensions with different behavioral outcomes underlie IWAH.
Challenges of glycoprotein analysis by microchip capillary gel electrophoresis
Authors: Engel Nicole , Weiss Victor U. , Wenz Christian , Rüfer Andreas , Kratzmeier Martin , Glück Susanne , Marchetti‐Deschmann Martina , Allmaier Günter
Published: April 2015

Glycosylations severely influence a protein's biological and physicochemical properties. Five exemplary proteins with varying glycan moieties were chosen to establish molecular weight (MW) determination (sizing), quantitation, and sensitivity of detection for microchip capillary gel electrophoresis (MCGE). Although sizing showed increasing deviations from literature values (SDS‐PAGE or MALDI‐MS) with a concomitant higher degree of analyte glycosylation, the reproducibility of MW determination and accuracy of quantitation with high sensitivity and reliability were demonstrated. Additionally, speed of analysis together with the low level of analyte consumption render MCGE attractive as an alternative to conventional SDS‐PAGE.