bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of 13,14‐Dehydro‐prostaglandins Synthetic Analogues: A Review
Authors: Monteiro Sara , Paraskevopoulos Georgios , Imramovský Aleš
Published: October 2019

Prostaglandins (PG) are a group of lipid mediators with several biological activities. Their structure includes a five‐membered ring and two lateral chains (α and ω‐ chains). Due to their pharmaceutical and veterinary applications numerous synthetic analogues have been prepared and are described in literature. 13,14‐dehydroPG are synthetic analogues including a triple bond in their skeleton which provide them a more preferable biological behaviour. However, these compounds require special approaches for their synthesis and attachment of its ω‐chain when compared with allylic PG (double bond at position 13–14 of PG numbering). This review intends to summarize available strategies for the introduction of the ω‐chains when a triple bond moiety (at position C13‐14) is present.
Efficient Synthesis of Benzofurans via Cross‐Coupling of Catechols with Hydroxycoumarins Using O2 as an Oxidant Catalyzed by AlPO4‐Supported Rh Nanoparticle
Authors: Maeno Zen , Yamamoto Masanobu , Mitsudome Takato , Mizugaki Tomoo , Jitsukawa Koichiro
Published: October 2019

An efficient synthesis of benzofuran derivatives via the cross‐coupling of catechols and hydroxycoumarins in H2O using O2 as an ideal oxidant is reported. The above reaction allows the direct use of substrates without prefunctionalization, involves formation of C−C and C−O bonds in cascade manner, and affords H2O as the sole by‐product. This simple and clean reaction is achieved by the development of an AlPO4‐supported Rh nanoparticle catalyst. The catalyst was applicable to the synthesis of a wide range of benzofurans. We also successfully utilized this catalytic method for total synthesis of flemichapparin C, one of the naturally occurring coumestans exhibiting bioactivity. The combined functions of Rh nanoparticles and AlPO4 play a key role in this reaction where in situ generated o‐benzoquinone by Rh nanoparticles is possibly an intermediate for nucleophilic addition to hydroxycoumarins on AlPO4.
Chiral Squaramide Catalyzed Asymmetric [3+2] Cycloaddition Reaction for Synthesis of Trifluoromethylated Barbituric Acid Derivatives
Authors: An Tian‐Li , Du Da‐Ming
Published: October 2019

A squaramide catalyzed asymmetric Michael/Mannich [3+2] cycloaddition reaction between N‐2,2,2‐trifluoroethyl isatin ketimines and barbiturate‐based olefins was developed. The corresponding trifluoromethylated dispirobarbituric acid derivatives containing three stereocenters were obtained in excellent yields and stereoselectivities (up to 99% yield, 99:1 dr and >99% ee). In addition, the gram‐scale reaction also achieved with excellent yield and stereoselectivity.
Enhanced Epoxy/GO Composites Mechanical and Thermal Properties by Removing Air Bubbles with Shear Mixing and Ultrasonication
Authors: Chisty Adib H. , Mallik Abul K. , Robel Fataha N. , Shahruzzaman Md. , Haque Papia , Hossain Khandker S. , Khan Ruhul A. , Rahman Mohammed Mizanur
Published: October 2019

Epoxy‐graphene oxide composites were prepared through the homogeneous dispersion of graphene oxide (GO) in epoxy via shear mixing and ultrasonication techniques. Mechanical and thermal properties of the composites were evaluated. Final composite samples were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, optical microscope, differential scanning calorimetry, thermogravimetric analysis, and x‐ray diffraction analyses. The thickness of the prepared GO sheet was calculated by atomic force microscopy. Herein, we report a remarkable enhancement in thermal along with mechanical properties of diglycidyl ether of bisphenol‐A (DGEBA) based epoxy matrix upon adding small amounts (≤1.5 wt%) of GO into the glassy epoxy system. With the incorporation of only 0.5 wt% GO the tensile strength and Young's modulus were found to be increased by 67.4% and 43.2%, respectively compared to neat epoxy; in addition, 3.7 folds improvement was achieved in the impact strength at the same GO content. In agreement with mechanical properties, resulting composites also showed better thermal stability together with promising improvement in glass transition temperature. The glass transition temperature was enhanced by 25.8 °C for the composite with 0.1 wt% GO. Therefore, the prepared composite will have potential applicability in the field of material science with improved mechanical and thermal response.
Synthetic Studies Toward the Flatworm‐Derived Alkaloid Pseudocerosine
Authors: Kim Se Hun , Sperry Jonathan
Published: October 2019

Pseudocerosine, the pigment responsible for the vivid blue spots along the tunic rim of the marine flatworm Pseudoceros indicus, possesses a molecular framework that is unique among heteroaromatic natural products. Herein we provide an overview of several synthetic approaches to the alkaloid pseudocerosine, focusing in particular on the azafulvene‐embedded azepinoindole and the aminal moiety. Two distinct approaches to the azepinoindole core were successful. The first involved C−H borylation of a tryptamine derivative followed by Suzuki‐Miyaura coupling with an α‐bromoenone and base mediated cyclisation. The second involved the selective formation of a conjugated enamine from a tryptamine and an enone, followed by an acid‐mediated Mannich‐type enamine cyclisation. It has also been demonstrated that the unusual aminal present in pseudocerosine can be installed by the reaction of acetamide with a pyridoindole‐based iminium ion. These studies provide valuable insight into the reactivity and stability of the pseudocerosine core structure and serve as a platform for its total synthesis.
Hot Ductility and Fracture Phenomena of Low‐Carbon V–N–Cr Microalloyed Steels
Authors: Liu Yue , Du Lin-Xiu , Wu Hong-Yan , Misra R. Devesh Kumar
Published: October 2019

The hot ductility of low‐carbon V–N–Cr microalloyed steel is studied using a thermomechanical simulator. The steel is solution treated at 1350 °C and cooled at 15 °C s−1 to the test temperature in the range of 650–1200 °C. Next, they are strained to failure at a strain rate of 4 × 10−3 or 4 × 10−2 s−1, and ductility troughs are obtained. The results reveal a ductility trough in V–N–Cr steels in the range of 650–900 °C with a minimum reduction in area (RA) value of 13.5 % at 800 °C and strain rate of 4 × 10−3 s−1. The occurrence of dynamic recrystallization from 950 to 1200 °C has a substantial contribution to high ductility and on the formation of film‐like ferrite at prior austenite grain boundaries. The fracture mechanism changes from intergranular to highly ductile microvoid coalescence in the temperature range of 800–1200 °C and at a higher strain rate. Ductility loss in the V–N–Cr steel is caused by the presence of a high density of VN and/or V(C,N) precipitates, which are linearly present within the matrix, and a small number of random precipitates are present at the boundary.
Evolution of Carbides in Cr–Mo–Si–V Alloy Steel during the Spheroidization Annealing Process
Authors: He Shuai , Li Changsheng , Ren Jinyi , Gao Cairu , Zhang Yongqiang
Published: October 2019

The evolution of eutectic carbide and granular pearlite, including secondary carbide and matrix ferrite, in 1.12C–8.1Cr–2.3Mo–1.08Si–0.32V alloy steel under spheroidization annealing is investigated. This procedure can be divided into two stages: austenitization in the range of 780–900 °C for 0.5–5 h and second annealing in the range of 740–780 °C for 3–7 h. The area fraction, size, number per unit area, and sphericity of carbides are analyzed under different annealing processes. The result indicates that the mean diameter of secondary carbides increases and the number of carbides per area decreases with the increase in temperature in two ranges of 780–900 and 740–780 °C. At >860 °C, the secondary carbide sufficiently spheroidizes, the eutectic carbide dissolves at the tip with a larger radius of curvature, and ferrite grains of the matrix are basically equiaxed. It can be found that the austenitizing stage plays a crucial role in nucleation and coarsening of secondary carbides, dissolution and segmentation of eutectic carbides, and recrystallization of matrix ferrite grains. The microhardness of the sample presents a decreasing tendency from fast to slow with the increase of the average diameter of secondary carbides.
Property‐Driven Development of Metallic Structural Materials by Combinatorial Techniques on the Example of Fe–C–Cr Steels
Authors: Baron Christian , Springer Hauke
Published: October 2019

The use of high‐throughput techniques allows for rapid property‐driven materials development. Attractive material profiles are systematically screened and processed on the example of the ternary Fe–C–Cr system into yet unexplored regions. The effect of various combinations of Cr additions (2, 4, 6, 8, 10 wt%) on the mechanical properties and microstructures of Fe–0.2C (wt%) and Fe–0.8C (wt%)‐based steels are studied depending on their hardening (850–1150 °C; 20 min) and tempering conditions (100–600 °C; 1 h), producing 120 different material states. Wide ranges of potentially interesting material profiles are obtained with strengths up to 1.8 GPa ultimate tensile strength (UTS) or hardness of 700 HV5. Individual trends for materials’ mechanical performance are identified, but straightforward interpretation of trends holds complex multi‐dimensional analytical challenges of this high‐throughput bulk metallurgical screening. Methods addressing these problems are outlined and the possibilities of assistive computational data processing and analysis are discussed.
Moderne Separatoren in der Stärkeindustrie
Authors: Hoffmann W.
Published: October 2019

Der Stärkeindustrie stehen Düsenseparatoren verschiedener Größe jeweils in normaler Ausführung und vor allem in zwei Spezialausführungen zur Verfügung, nämlich mit Waschvorrichtung oder mit innerer Zirkulation.

Die innere und die äußere Zirkulation und ihre Bedeutung für die Konzentrationsregelung wurden besprochen.

Für die Anwendung von Separatoren in der Maisund in der Kartoffelstärkefabrik wurden Beispiele gebracht und das in der Verfahrenstechnik für Gegenstromprozesse typische Rücklaufverhältnis erwähnt.

Zur schnellen Beurteilung der Betriebsweise von Düsenseparatoren wurde das °Bé‐Mengen‐Bild vorgeschlagen.

Eine besondere Bauart eines Konzentrationsreglers für Separatorenanlagen wurde beschrieben.
Die Bestimmung des Phosphorsäuregehaltes der Kartoffelstärke auf komplexometrischem und alkalimetrischem Wege
Authors: Winkler S.
Published: October 2019

Es werden schnell und einfach durchführbare Bestimmungsmethoden der Phosphorsäure in Kartoffelstärken beschrieben, die auf dem quantitativen Ionenaustausch der Stärke beruhen.

Der Kationenaustausch verläuft bei Stärken an der zweibasischen Phosphorsäureestergruppe, als der funktionellen Gruppe des Ionenaustausches, stufenweise und ist stark pH‐abhängig; der Ionenaustausch führt mit Säuren zu den H‐Ionen‐Stärken (H‐Stärken), in neutralen oder schwach sauren Salzlösungen zu Stärken mit primären Metallphosphatgruppen (monovalenter Ionenaustausch), mit Alkalien oder in alkalischen Salzlösungen zu Stärken mit sekundären Metallphosphatgruppen(bivalenter Ionenaustausch).

Aus den sehr unterschiedlichen pH‐Werten der nur schwach sauren primären Metallphosphatstufe (pH 5–6) gegenüber dem alkalischen pH der sekundären Metallphosphatstufe (pH 8–9) in Kartoffelstärken kann auf das Überwiegen der primären Metallphosphatstufe in normalen Stärken geschlossen werden.

Die H‐Stärken haben als die metallionenfreie und reinste Form der Stärke für die Analytik der Stärken besonderes Interesse; ihre Eignung für die Lösung grundsätzlicher Fragen der Viskosität sowie der quantitativen Beziehung zwischen Viskosität und Phosphorsäuregehalt wird erörtert.

In der Valenzbindung zweibasischer Metalle bei der primären Metallphosphatstufe von Stärken kann eine Erklärung für die starke viskositätsmindernde Wirkung zweibasischer Metalle, wie Calcium, Magnesium u.a. gegeben werden; es ist wahrscheinlich, daß Brückenvalenzbindung, die durch Verknüpfung von zwei Phosphorsäureestergruppen durch die beiden Valenzen des Metalls erfolgt, nur zwischen zwei verschiedenen Glukoseketten stattfinden kann; dadurch wird eine Kontraktion des Stärkemoleküls verursacht, die in einem Viskositätsabfall bei der Verkleisterung der Stärke zum Ausdruck kommt.
Veränderungen bei der Stärke und anderen Kohlenhydraten durch thermische Einflüsse
Authors: Diemair W. , Hufnagel E.
Published: October 2019

Die vorliegende Arbeit berichtet über die Veränderungen der Kohlenhydrate von Kartoffeln bei der Herstellung von Trockenprodukten.

Bei allen untersuchten deutschen Kartoffelsorten und auch bei den aus ihnen hergestellten Trockenprodukten konnten Saccharose, Glucose und Fructose nachgewiesen werden. Xylose, die eine schnelle Verfärbung der Trockenprodukte bewirken soll, war nicht vorhanden.

Der Gehalt an reduzierenden Zuckern schwankt in Frischkartoffeln zwischen 1,0% und 4,7% i. Tr und in Trockenprodukten zwischen 1,7 % und 2,9% i.Tr. Nach Untersuchungen amerikanischer Forscher sollen Kartoffeltrocknungserzeugnisse mit einem Wassergehalt von 6% nicht mehr als 2,7% reduzierende Zucker enthalten. Diese Voraussetzung ist mit Ausnahme einer Probe bei allen untersuchten Trockenprodukten erfüllt.

Eine elektrophoretische Auftrennung der Stärke in ihre Bestandteile Amylose und Amylopektin war mit Boratpuffer (pH = 10) und bei einer Spannung von 1900 V nur bei der Verwendung von löslicher Stärke möglich, da weder Kartoffelstärke noch Weizenstärke in Boratpuffer in Lösung zu bringen war. Auch durch Herstellung eines Stärkeglykolats konnte keine Auftrennung in Amylose‐ und Amylopektinglykolat erreicht werden.

Bei der Auftrennung der Stärkebestandteile an einer sauren‐basischen Aluminiumoxydsäule konnte bei der Untersuchung von thermisch behandelter Stärke aus Kartoffelpulver eine Aufspaltung der höhermolekularen Amylopektinbestandteile festgestellt werden. Diese Aufspaltung setzt bei der Herstellung der Trockenprodukte schon beim Dämpfprozeß ein.

Der Durchschnittspolymerisationsgrad von Kartoffeltrocknungsprodukten liegt zwischen 138 und 170 Anhydroglucose‐Einheiten. Für reine Amylopektinstärke wurden 2000, für eine Maisstärke mit 50% Amylose 214 und für eine selbst hergestellte Kartoffelstärke 1250 Anhydroglucose‐Einheiten ermittelt. Die Veränderung der Stärke und der anderen höhermolekularen Kohlenhydratbestandteile bei der Herstellung von Trockenprodukten findet nicht durch Hitzeeinwirkung beim Trocknungsprozeß, sondern schon beim Dämpfprozeß statt. Der niedrige Polymerisationsgrad ist nicht nur auf Abbauvorgänge im Stärkemolekül (Depolymerisation der Amylopektinmoleküle) sondern in geringem Umfang auch auf die Miterfassung von niedermolekularen Polysacchariden, die als Bestandteile des Kartoffelfruchtfleisches vorkommen, zurückzuführen.

Der Amylosegehalt der untersuchten Trockenprodukte schwankt zwischen 23,0% und 29,5%. Der unterschiedliche Amylosegehalt ist in erster Linie durch die Verwendung verschiedener Kartoffelsorten bedingt. Nach dem Dämpfen unter einem Druck von ½ atü und einem Druck von 1 atü ist eine geringfügige Abnahme des Amylosegehaltes zu beobachten. Eine Depolymerisation des Amylopektins läßt sich mit dieser Methode nicht nachweisen.
Die letzten zehn Jahre Stärke‐Forschung
Authors: Whistler Roy L. , Spencer W. William
Published: October 2019

Es wird eine Übersicht über die Ergebnisse der Stärkeforschung gegeben, die in den vergangenen zehn Jahren erzielt wurden.

Mit Hilfe des Elektronenmikroskops wurden neue Erkenntnisse über die Bildung und den Feinbau der Getreidestärkekörner gewonnen.

Es wurden wirtschaftliche Methoden zur Trennung von Amylose und Amylopektin entwickelt. Außerdem wurden ausgedehnte Versuche zur Züchtung von Mais mit hohem Amylosegehalt unternommen, die bereits zur Entwicklung verschiedener Maissorten mit einem Amylosegehalt bis zu 75% geführt haben. Durch Fortsetzung der Versuche hofft man, den Amylosegehalt der Maisstärke auf 90 bis 95% zu erhöhen.

Über den enzymatischen Abbau und Aufbau der Stärke wurden neue Erkenntnisse gewonnen. Hierbei spielen insbesondere α‐Amylase, β‐Amylase, R‐Enzym, Q‐Enzym und Phosphorylase eine Rolle. α‐Amylase und β‐Amylase sind beispielsweise für die Bildung von vergärbaren Zuckern wichtig, die bei der Herstellung von Backwaren als Hefenahrung dienen, dem Gebäck den gewünschten Geschmack verleihen und zur Bräunung der Krume beitragen.

Ein weiteres wichtiges Gebiet der Stärkeforschung sind die Stärkederivate. Von den Stärkeestern haben insbesondere die Stärkephosphate und ‐sulfate mit niedrigem Substitutionsgrad technische Bedeutung erlangt. Stärkeäther eignen sich als Schlichtemittel oder Leime in der Textil‐, Papier‐ und Klebstoffindustrie. Oxydierte Stärken finden Verwendung bei der Herstellung von gestrichenen Papieren.
Zur Bestimmung der auswaschbaren Stärke in der Kartoffelpülpe
Authors: Bergmann A.
Published: October 2019

Die Bestimmung der auswaschbaren Stärke in der Kartoffelpülpe wird durch Einsatz eines speziellen Filtertrichters beschleunigt, mit dessen Hilfe die Dauer des Zentrifugierens der Stärkemilch von 50 auf 10 Minuten herabgesetzt werden kann.
Der Einfluß von Gammastrahlen und Ultraschall auf Stärke
Authors: Samec M.
Published: October 2019

Es werden die Veränderungen beschrieben, welche Kartoffel‐, Weizen‐ und Maisstärke unter dem Einfluß von Gammastrahlen und Ultraschall erfahren. Gemessen wurden folgende Eigenschaften: Viskosität, Reduktionsvermögen, PH ‐ Wert, Jodbindungsvermögen, Molekulargewicht, ultrafiltrierbarer Anteil, Verhalten bei der Elektrodialyse. Die gleichen Eigenschaften wurden an den elektrodialytisch gewonnenen Fraktionen, deren Phosphorgehalt bestimmt wurde, untersucht.

Beide Behandlungsweisen ermöglichen die Gewinnung von löslichen Stärken, deren wäßrige Lösungen über längere Zeit gut beständig sind.

Die Gammastrahlenwirkung zeigt einen Weg zur Auswertung der bei Reaktionen anfallenden “Abfallenergie” auf.
Die Hydratation der Stärke
Authors: Schierbaum F.
Published: October 2019

Es wurde ein kritischer Überblick über die im Schrifttum vorliegenden Angaben zur Hydratation der Stärke im heterogenen System Stärke‐Wasser (Dampf) gegeben. Besondere Berücksichtigung fanden dabei Angaben über die Menge des von den einzelnen Stärkearten bei verschiedenen relativen Luftfeuchtigkeiten ad‐ und desorbierten Wassers, die kolloidchemische Charakterisierung dieser Vorgänge, die Erscheinungen der Hysteresis und die Unterschiede zwischen den Stärkearten. Ferner wurden die von den verschiedenen Autoren vertretenen Ansichten über den Mechanismus der Wasserbindung in der Stärke besprochen. Das vorliegende Material weist in diesen Fragen zum Teil erhebliche Widersprüche auf, die einer experimentellen Klärung bedürfen.
Die Hydratation der Stärke
Authors: Schierbaum F.
Published: October 2019

Zur vergleichenden Untersuchung der Wassersorption von Kartoffel‐, Weizen‐, Mais‐ und Reisstärke wurden die Gleichgewichtswerte bei Wassersättigung sowie die Ad‐ und Desorptionsisothermen nach zwei verschiedenen Verfahren aufgenommen. Weiterhin wurde der Einfluß verschiedener Trocknungsarten auf die Größe der Sorption untersucht. Der Einfluß der Stärkestruktur auf die Wassersorption wurde an verkleisterten und mittels Methanol ausgefällten Kartoffel‐, Weizen‐, Mais‐ und Reisstärken untersucht.

Die durchgeführten Messungen führten zu folgenden Ergebnissen:

Die Werte für die Wassersorption nehmen in der Reihenfolge Reis‐, Mais‐, Weizen‐, Kartoffelstärke zu; dabei sind die Unterschiede zwischen den Stärkearten bei Wassersättigung am größten, vermindern sich bei abnehmender rel. Feuchte und verschwinden bei den Getreidestärken unterhalb 68% rel. F. und zwischen Kartoffel‐ und Getreidestärken unterhalb 35%.

Bei den unverkleisterten Stärken ist die Größe der Wassersorption in allen Feuchtigkeitsbereichen bei gleicher Temperatur von der angewandten Methodik — Messung bei Atmosphärendruck innerhalb von 20 bis 120 Tagen bzw. Messung unter vermindertem Luftdruck in 10–50 Stunden— praktisch unabhängig.

Durch thermische Trocknungsverfahren wird bei allen vier Stärkearten die Fähigkeit zur Wasseraufnahme bei Wassersättigung der Atmosphäre herabgesetzt. Dieselben Stärken zeigten dagegen nach Methanolentwässerung und Vakuumtrocknung eine erhöhte Fähigkeit zur Wasseraufnahme.

Durch Verkleistern und anschließende Methanolfällung erhaltene Quellstärken zeigten bei Wassersättigung eine auf über 40 % H2O erhöhte Sorptionsfähigkeit. Dabei sind die Unterschiede zwischen den Stärkearten fast völlig verschwunden. Unterhalb 79 bis 68 % rel. F. sind die Sorptionsisothermen mit denen der unverkleisterten Stärken praktisch identisch.

Die Isothermen zeigen bei Auswertung nach der Freundlich'schen Isothermengleichung log a = f (lg x) bei doppelt logarithmischer Darstellung zwischen 0 und 68 % rel. F. mit unterschiedlichen Neigungskoeffizienten angenähert linearen Verlauf und gehen bei zunehmender Wassersättigung ohne merklichen Übergang in einen steil ansteigenden Ast über.

Aus der Abweichung von der Gültigkeit der Freundlich‘schen Isothermen wird auf eine Wasserbindung der Stärke im Bereich höherer rel. Feuchtigkeiten durch Kapillarkondensation geschlossen, deren Größe von der Oberflächenbeschaffenheit des Sorbens und den Sorptionsbedingungen abhängig ist. Unterhalb dieses kritischen Punktes der Isothermen ist die Wasserbindung der Stärke vorwiegend eine für die Stärkekohlenhydrate spezifische Stoffeigenschaft und erfüllt die für einen reinen Adsorptionsvorgang geltende Freundlich‘sche Gleichung.
The Effects of Salts on the Gelatinization of Wheat Starch
Authors: Sandstedt R. M. , Kempf W. , Abbott R. C.
Published: October 2019

Zusammenfassung und Schlußfolgerung

Es werden die unterschiedlichen Einflüsse von Salzlösungen auf die Anfangsverkleisterungstemperatur von Weizenstärke beschrieben.

Salzlösungen verändern nicht nur die Temperatur, bei der die Verkleisterung beginnt, sondern bewirken gleichzeitig auch eine beachtliche Veränderung der Merkmale des gesamten Verkleisterungsvorganges. Diese Veränderungen, die sich auf die Temperatur zu Beginn der ersten Phase, den Verkleisterungsgrad innerhalb der ersten Phase, die Länge der Übergangsperiode zwischen der ersten Phase und der zweiten Phase, die Temperatur zu Beginn der zweiten Phase und den Verkleisterungsgrad innerhalb der zweiten Phase beziehen, stehen in keiner Korrelation zueinander. So läßt beispielsweise weder eine Erniedrigung der Anfangsverkleisterungstemperatur irgendwelche Schlüsse auf diejenigen Veränderungen zu, die innerhalb der folgenden Stadien eintreten, noch stehen die Veränderungen innerhalb der folgenden Stadien in irgendeiner Beziehung zueinander. Aus diesen Feststellungen ergibt sich, daß die Veränderungen, die durch eine Salzlösung in dem Verkleisterungsbild hervorgerufen werden, nicht auf eine ganz bestimmte Eigenschaft der Salzlösung zurückzuführen sind, sondern daß jede Veränderung die Folge von unterschiedlichen Eigenschaften der Lösung ist. Die bisher erhaltenen Ergebnisse zeigen die außerordentliche Verschiedenheit der Einflüsse von Salzen auf die Verkleisterung. Sie reichen jedoch noch nicht aus, um auch die unterschiedlichen Einflüsse der einzelnen Salze vergleichend erklären zu können. Entsprechende Studien dieser Einflüsse von Salzen auf die Verkleisterung sind zur Zeit noch im Gange.

Anerkennung

Die Autoren danken der Corn Industries Research Foundation, Incorporated, Washington, D. C., USA., und der W. K. Kellogg Foundation, Battle Creek, Michigan, USA., für die ihnen gewährte Förderung bei der Durchführung dieser Arbeit.
Effect of nano‐SiO2 on properties and microstructure of polymer modified cementitious materials at different temperatures
Authors: Meng Tao , Yu Hongming , Lian Songsong , Meng Ruitan
Published: October 2019

In this study, the effect of nano‐SiO2 on mechanical properties and microstructure of polymer modified cementitious (PMC) materials under 20 and 6°C was studied through strength test, X‐ray Diffraction Analysis, Mercury Intrusion Porosimetry, and Scanning Electron Microscopy. Results showed that the flexural and compressive strength of cement mortar was influenced seriously by polymer especially under low temperature condition. And nano‐SiO2 was contributed to enhance the flexural and compressive strength of PMC materials at early age under 20°C while the enhancement still existed at later age under 6°C. The disadvantage of polymer on the properties and microstructure of PMC materials at low temperature was modified by nano‐SiO2 due to the increase of hydration rate of cement, the decrease of the Ca(OH)2 (CH) orientation aggregation, the modification of pore structure, and the promotion of polymer film formation. This study provides a prospective method on the performance optimization of PMC materials.
A unified description of translational symmetry breaking in holography
Authors: Ammon Martin , Baggioli Matteo , Alba Amadeo Jimenez
Published: October 2019

Abstract

We provide a complete and unified description of translational symmetry breaking in a simple holographic model. In particular, we focus on the distinction and the interplay between explicit and spontaneous breaking. We consider a class of holographic massive gravity models which allow to range continuously from one situation to the other. We study the collective degrees of freedom, the electric AC conductivity and the shear correlator in function of the explicit and spontaneous scales. We show the possibility of having a sound-to-diffusion crossover for the transverse phonons. Within our model, we verify the validity of the Gell-Mann-Oakes-Renner relation. Despite of strong evidence for the absence of any standard dislocation induced phase relaxation mechanism, we identify a novel relaxation scale controlled by the ratio between the explicit and spontaneous breaking scales. Finally, in the pseudo-spontaneous limit, we prove analytically the relation, which has been discussed in the literature, between this novel relaxation scale, the mass of the pseudo-phonons and the Goldstone diffusivity. Our numerical data confirms this analytic result.
Ethical Concerns in Poultry Production: A German Consumer Survey About Dual Purpose Chickens
Authors: Busse Maria , Kernecker Maria Lee , Zscheischler Jana , Zoll Felix , Siebert Rosemarie
Published: October 2019

The paper offers insights into the acceptability of ethical issues in poultry production and how this situation provides an opportunity to transform the prevailing system into a more sustainable one. The survey among German consumers reveals that killing day-old chicks is a well-known practice and is rated as “very problematic”. In contrast, dual-purpose chickens are mostly unknown but are considered a positive alternative to killing day-old chicks (after the concept has been explained). Consumer clusters were identified regarding purchasing criteria for dual-purpose chickens, purchasing routines and socio-economic factors. Three of the five clusters—the perfectionists, idealists, and realists—turned out to be potential buyers. To develop a suitable marketing strategy, it is recommended that the added value of dual-purpose chickens be comprehensibly communicated. From a multi-level perspective, rearing dual-purpose chickens has a competitive disadvantage compared to system-compliant alternatives (in-ovo sexing, “lay hen brothers”). Through increasing external pressure, the different alternatives can jointly contribute to a regime shift.
Low-background, digital gamma-ray spectrometer with BEGe detector and active shield: commissioning, optimisation and software development
Authors: Gorzkiewicz Krzysztof , Mietelski Jerzy Wojciech , Kierepko Renata , Brudecki Kamil
Published: October 2019

This paper presents results of the development process of low-background, digital gamma-rays spectrometer equipped with Broad Energy Germanium detector (CANBERRA BE5030), multi-layer passive shield and cosmic veto system that consists of five plastic scintillators (SCIONIX EJ-200). Data acquisition is performed using digitizer CAEN DT5725 with CoMPASS software. Output data analysis is carried out with purposely written and developed code VETO. On the basis of conducted tests, acquisition parameters were set up and tuned as well as time delays between all detectors were established. As a result of the configuration process, the mean background counts reduction of 64% in the whole spectrum and 65% in annihilation peak were achieved. This procedure allowed diminishing detection limits of selected isotopes 37% on average.
Change versus stability: are protected areas particularly pressured by global land cover change?
Authors: Guerra Carlos António , Rosa Isabel M. D. , Pereira Henrique M.
Published: October 2019

Context

Land cover change is a global multi-scale process affecting ecosystems, with potential implications for ecological processes and for the biological communities that support them. Land cover changes are especially relevant for protected areas where long-term ecosystem stability is a critical aspect of protecting and maintaining high levels of biodiversity and ecosystem functions.

Objectives

To understand the extent of land cover change impact on global ecosystem stability of protected areas across time and space.

Methods

Here we analysed 23 years of global spatial and temporal distribution of land cover change its occurrence within protected areas. We investigated whether higher land cover change rates occurred inside or outside protected areas, identified the main type of changes, and their distribution by UN region.

Results

Our results show that from 1992 to 2015, 4.89% of the world’s land surface changed from one land cover to another, with 97.9% of this change persisting until the end of the time period. We found that regions with higher land cover change, tend to have a higher incidence of change close to protected areas, suggesting a spillover effect on these areas. Also, the proportion of change inside and outside protected areas varied considerably across UN Regions.

Conclusions

Our results suggest that to reach current global conservation targets, it is not enough to increase the targets of protected area coverage. Instead, governments and conservation management agencies should account for regional specificities, and pay attention to the territories surrounding protected areas to develop strategies to reduce spillover effects.
Interpersonal Counseling in the Treatment of Adolescent Depression: A Randomized Controlled Effectiveness and Feasibility Study in School Health and Welfare Services
Authors: Parhiala P. , Ranta K. , Gergov V. , Kontunen J. , Law R. , La Greca A. M. , Torppa M. , Marttunen M.
Published: October 2019

In order to offer early and accessible treatment for adolescents with depression, brief and effective treatments in adolescents’ everyday surroundings are needed. This randomized controlled trial studied the preliminary effectiveness, feasibility, and acceptability of interpersonal counseling (IPC) and brief psychosocial support (BPS) in school health and welfare services. The study was conducted in the 28 lower secondary schools of a large city in Southern Finland, randomized to provide either IPC or BPS. Help-seeking 12–16-year-old adolescents with mild-to-moderate depression, with and without comorbid anxiety, were included in the study. Fifty-five adolescents received either 6 weekly sessions of IPC or BPS and two follow-up sessions. Outcome measures included self- and clinician-rated measures of depression, global functioning, and psychological distress/well-being. To assess feasibility and acceptability of the treatments, adolescents’ and counselors’ treatment compliance and satisfaction with treatment were assessed. Both treatments were effective in reducing depressive disorders and improving adolescents’ overall functioning and well-being. At post-treatment, in both groups, over 50% of adolescents achieved recovery based on self-report and over 70% based on observer report. Effect sizes for change were medium or large in both groups at post-treatment and increased at 6-month follow-up. A trend indicating greater baseline symptom severity among adolescents treated in the IPC-providing schools was observed. Adolescents and counselors in both groups were satisfied with the treatment, and 89% of the adolescents completed the treatments and follow-ups. This trial suggests that both IPC and BPS are feasible, acceptable, and effective treatments for mild-to-moderate depression in the school setting. In addition, IPC seems effective even if comorbid anxiety exists. Our study shows that brief, structured interventions, such as IPC and BPS, are beneficial in treating mild-to-moderate depression in school settings and can be administered by professionals working at school.

Trial registrationhttp://www.clinicaltrials.gov. Unique identifier: NCT03001245.
Measurement and implications of marine food security in the Western Indian Ocean: an impending crisis?
Authors: Taylor Sarah F. W. , Roberts Michael J. , Milligan Ben , Ncwadi Ronney
Published: October 2019

Ten percent of the world’s population depends on the ocean for a readily accessible source of protein and employment. Coastal ecosystems and the communities that rely upon them are facing extreme challenges of increases in ocean pollution, loss of habitat, ocean warming, and changes in ocean productivity. With the whole system under mounting pressure, governments need to scale down food security analyses to the coastal community level to avoid overseeing rising levels of food insecurity. This paper provides an alternative view and analysis of food security at both a national and community level taking into account these marginalised communities. The results propose a refined definition of marine food security and new quantitative methods to measuring direct and indirect reliance on fish within developing countries. Application of this concept and methods reveals that aggregated national statistics mask the extreme levels of dependence on fish for food security in coastal communities within Kenya and Madagascar. The Comoros, Mauritius, Mozambique, and Somalia appear to be the most vulnerable to increasing sea surface temperature, population, and fluctuation in total catch and will be severely affected by a changing Western Indian Ocean from a national, community, and individual perspective. Overall, the study highlights that governments need to disaggregate fisheries data and redefine measurements of food security to more accurately reveal the severity of the potential marine food insecurity crisis at hand.
Optimizing the Performance of CsPbI3-Based Perovskite Solar Cells via Doping a ZnO Electron Transport Layer Coupled with Interface Engineering
Authors: Yue Man , Su Jie , Zhao Peng , Lin Zhenhua , Zhang Jincheng , Chang Jingjing , Hao Yue
Published: October 2019

Interface engineering has been regarded as an effective and noninvasive means to optimize the performance of perovskite solar cells (PSCs). Here, doping engineering of a ZnO electron transport layer (ETL) and CsPbI3/ZnO interface engineering via introduction of an interfacial layer are employed to improve the performances of CsPbI3-based PSCs. The results show that when introducing a TiO2 buffer layer while increasing the ZnO layer doping concentration, the open-circuit voltage, power conversion efficiency, and fill factor of the CsPbI3-based PSCs can be improved to 1.31 V, 21.06%, and 74.07%, respectively, which are superior to those of PSCs only modified by the TiO2 buffer layer or high-concentration doping of ZnO layer. On the one hand, the buffer layer relieves the band bending and structural disorder of CsPbI3. On the other hand, the increased doping concentration of the ZnO layer improves the conductivity of the TiO2/ZnO bilayer ETL because of the strong interaction between the TiO2 and ZnO layers. However, such phenomena are not observed for those of a PCBM/ZnO bilayer ETL because of the weak interlayer interaction of the PCBM/ZnO interface. These results provide a comprehensive understanding of the CsPbI3/ZnO interface and suggest a guideline to design high-performance PSCs.
TOPDRIVER: the novel identifier of cancer driver genes in Gastric cancer and Melanoma
Authors: Razavi Seyed Mohammad , Rami Farzaneh , Razavi Seyede Houri , Eslahchi Changiz
Published: October 2019

Nowadays, research has found a strong relationship between genomic status and occurrence of disease. Cancer is one of the most common diseases that leads to a high annual mortality rate worldwide, and the disease’s genetic content remains challenging. Detecting driver genes of different cancers could help in early diagnosis and treatment. In this paper, we proposed TOPDRIVER, a network-based algorithm, to detect cancer driver genes in cancers. An initial network was constructed by integrating four different omic datasets: HPRD, NCBI, KEGG, and GTEx. This integration created a gene similarity profile that provided a comprehensive perspective of gene interaction in each subtype of cancer and allocated weights to the edges of the network. The vertex scores were calculated using a gene-disease association dataset (DisGeNet) and a molecular functional disease similarity. In this step, the genes network was jagged and faced with a zero-one gap problem. A diffusion kernel was implemented to smooth the vertex scores to overcome this problem. Finally, potential driver genes were extracted according to the topology of the network, genes overall biological functions, and their involvement in cancer pathways. TOPDRIVER has been applied to two subtypes of gastric cancer and one subtype of melanoma. The method could nominate a considerable number of well-known driver genes of these cancers and also introduce novel driver genes. NKX3-1, KIDINS220, and RIPK4 have introduced for gastrointestinal cancer, UBA3, UBE2M, and RRAGA for hereditary gastric cancer and CIT for invasive melanoma. Biological evidences represents TOPDRIVER’s efficiency in a subtype-specific manner.
Unusual Presentation and Imaging Findings of a Rare Supratentorial Neurenteric Cyst
Authors: Portela de Oliveira Eduardo , Woulfe John , Torres Carlos , Zakhari Nader
Published: October 2019

This is a case of a 30-year-old right-handed male patient who presented to the hospital in 2014 after hitting his head on the mat during a wrestling match followed by headache and temporary peripheral vision limitation. The patient’s past medical history was unremarkable. On physical examination, Glasgow Coma Scale was 15 with no focal neurological deficits. Unenhanced head computed tomography (CT) and enhanced brain magnetic resonance imaging (MRI) were performed (Figure 1). The patient was managed conservatively, and follow-up CT and MRI in 2015 (Figure 2) demonstrated significant decrease in size of the previously seen right frontoparietal lesion with also changes in its radiological features. The patient remained asymptomatic for about 3 years when in 2018 he presented to the Emergency Department with increasing headaches and peripheral vision loss. MRI demonstrated an increase in the right frontal lesion size (Figure 3). He underwent surgical resection of the lesion.
Anosov diffeomorphisms of products I. Negative curvature and rational homology spheres
Authors: NEOFYTIDIS CHRISTOFOROS
Published: October 2019

We show that various classes of products of manifolds do not support transitive Anosov diffeomorphisms. Exploiting the Ruelle–Sullivan cohomology class, we prove that the product of a negatively curved manifold with a rational homology sphere does not support transitive Anosov diffeomorphisms. We extend this result to products of finitely many negatively curved manifolds of dimension at least three with a rational homology sphere that has vanishing simplicial volume. As an application of this study, we obtain new examples of manifolds that do not support transitive Anosov diffeomorphisms, including certain manifolds with non-trivial higher homotopy groups and certain products of aspherical manifolds.
THE CITY AND LANDSCAPE OF UR: AN AERIAL, SATELLITE, AND GROUND REASSESSMENT
Authors: Hammer Emily
Published: October 2019

New fieldwork at Ur has begun to investigate urban scale, city organization, and the environment of the city's hinterland. Analysis of new sources of declassified aerial and satellite imagery from the 1950s and 1960s, recent unmanned aerial vehicle (UAV) photos, and a systematic surface collection show that Ur may have expanded to between 120–500 hectares in size during its later periods of habitation, far larger than the sixty hectare maximum size previously estimated. Traces of buried architecture visible in the UAV photos and topographic models generated from UAV photos allow for the generation of hypotheses about the city plan of Ur during the Late Larsa/Old Babylonian and Neo Babylonian periods. Relict watercourses mapped in the vicinity of the main mound indicate how the city might have been supplied with water in some periods. Alongside this site-based work, historical aerial and satellite imagery provide an updated picture of ancient hydrology, environment, and settlement patterns around Ur.
Reducing flow separation of an inclined plate via travelling waves
Authors: Akbarzadeh A. M. , Borazjani I.
Published: October 2019

Many aquatic animals propel themselves by generating backward traveling waves over their body, which is thought to reattach the flow when the wave speed ($C=\unicode[STIX]{x1D706}f$, where$\unicode[STIX]{x1D706}$is wavelength and$f$is frequency) is larger than the swimming speed ($U$). This has inspired the use of travelling waves, which have recently been generated at low amplitudes using smart materials, to reduce flow separation on an inclined plate. To see if low-amplitude travelling waves (amplitude approximately 0.01 of chord length$L$) can reduce the separation on an inclined plate, large-eddy simulations are performed. The simulations are carried out for Reynolds number ($Re$) 20 000 and an angle of attack of$10^{\circ }$with different wavelengths and frequencies. The travelling waves at a low reduced frequency ($f^{\ast }=fL/U=6$and$\unicode[STIX]{x1D706}^{\ast }=\unicode[STIX]{x1D706}/L=0.2$, where$U$is free-stream velocity) do not affect the flow separation and aerodynamic performance compared to the flat inclined plate. Nevertheless, increasing the wave speed by increasing the reduced frequency to 20 and 30 reduces flow separation. However, increasing the wave speed by increasing the wavelength, in contrast to the common belief, does not monotonically reduce the flow separation. In fact, increasing the wave speed by increasing the wavelength from 0.15 to 0.5 at constant frequency$f^{\ast }=20$increases the separation, but increasing from 0.5 to 1.0 and 2.0, interestingly, reduces flow separation. These observations indicate that the wave speed is not the only parameter for flow reattachment, but both wavelength and frequency individually impact flow separation by affecting two competing but interconnected mechanisms: the axial momentum, imparted onto the fluid by the undulations, tends to reattach the flow but the lateral velocity tends to detach it. In fact, increasing$f^{\ast }$and$\unicode[STIX]{x1D706}^{\ast }$increases both the axial momentum and the lateral velocity, which are competing to attach and detach the flow, respectively.
Shear thickening of a non-colloidal suspension with a viscoelastic matrix
Authors: Vázquez-Quesada Adolfo , Español Pep , Tanner Roger I. , Ellero Marco
Published: October 2019

We study the rheology of a non-colloidal suspension of rigid spherical particles interacting with a viscoelastic matrix. Three-dimensional numerical simulations under shear flow are performed using the smoothed particle hydrodynamics method and compared with experimental data available in the literature using different constant-viscosity elastic Boger fluids. The rheological properties of the Boger matrices are matched in simulation under viscometric flow conditions. Suspension rheology under dilute to semi-concentrated conditions (i.e. up to solid volume fraction $\unicode[STIX]{x1D719}=0.3$) is explored. It is found that at small Deborah numbers $De$ (based on the macroscopic imposed shear rate), relative suspension viscosities $\unicode[STIX]{x1D702}_{r}$ exhibit a plateau at every concentration investigated. By increasing $De$, shear thickening is observed, which is related to the extensional thickening of the underlying viscoelastic matrix. Under dilute conditions ($\unicode[STIX]{x1D719}=0.05$), numerical results for $\unicode[STIX]{x1D702}_{r}$ agree quantitatively with experimental data in both the $De$ and $\unicode[STIX]{x1D719}$ dependences. Even under dilute conditions, simulations of full many-particle systems with no a priori specification of their spatial distribution need to be considered to recover precisely experimental values. By increasing the solid volume fraction towards $\unicode[STIX]{x1D719}=0.3$, despite the fact that the trend is well captured, the agreement remains qualitative with discrepancies arising in the absolute values of $\unicode[STIX]{x1D702}_{r}$ obtained from simulations and experiments but also with large deviations existing among different experiments. With regard to the specific mechanism of elastic thickening, the microstructural analysis shows that elastic thickening correlates well with the average viscoelastic dissipation function $\unicode[STIX]{x1D703}^{elast}$, requiring a scaling as $\langle \unicode[STIX]{x1D703}^{elast}\rangle \sim De^{\unicode[STIX]{x1D6FC}}$ with $\unicode[STIX]{x1D6FC}\geqslant 2$ to take place. Locally, despite the fact that regions of large polymer stretching (and viscoelastic dissipation) can occur everywhere in the domain, flow regions uniquely responsible for the elastic thickening are well correlated to areas with significant extensional component.
Knowledge Sources and International Business Activity in a Changing Innovation Ecosystem: A Study of the Indian Pharmaceutical Industry
Authors: Sahasranamam Sreevas , Rentala Satyanarayana , Rose Elizabeth L.
Published: October 2019

The Indian pharmaceutical industry has experienced rapid growth, becoming the world's largest provider of generic drugs, based on product and process innovation. The industry has undergone dynamic changes in recent decades, operating in a rapidly evolving environment affected by domestic and global policies; a key example of the latter is the TRIPS agreement. Taking an intellectual property perspective, we describe how changes in the innovation ecosystem have affected companies’ strategies related to international activity and accessing knowledge from both internal and external knowledge sources, during the transitional- and post-TRIPS periods (1995–2004 and 2005–2014, respectively). Combining intellectual property arguments with contextual aspects of the innovation ecosystem, we conjecture that, in the post-TRIPS period, externally-sourced knowledge will be more important than internally-sourced knowledge, for Indian pharmaceutical firms’ international business activity.