bluuebunny/crossref_metadata_2025 huggingface dataset:
High strength steels and aluminium
alloys in lightweight body manufacturing
Authors: Tisza M.
Published: January 2018

Purpose: of this paper: The main objectives of this paper are to give an overview about the
application of various kinds of high strength steels and aluminium alloys in the automotive
industry to produce lightweight car body elements to achieve significant reductions in harmful
emissions to provide more environmental friendly vehicles which simultaneously fulfils the
increased safety requirements, too. In these respects, both high strength automotive steels
(e.g. DP, TRIP, TWIP and HPF steels), as well as high strength aluminium alloys (e.g. AA6082,
AA7075, etc.) are more and more widely applied in the vehicle manufacturing.
Design/methodology/approach: The contradiction between the increased strength and
lower formability of these high strength metallic materials is one of the main issues in their
application in the automotive industry. Therefore, in this paper primary focus will be placed on
the formability properties of these materials, concerning first of all the limits of formability in
various cold and hot forming conditions. To fully utilize the potentials of these materials in forming
processes the numerical modelling of forming with FEM simulation is of utmost importance.
Findings: Recently in the automotive industry the Hot Press Forming of high strength
boron-alloyed manganese steels become an industrially established process, while the
Hot Forming and Quenching (HFQ) of artificially ageing high strength aluminium alloys now
become the focus of scientific research. The paper will analyse the main process parameters
and gives comparisons of automotive applications.
Research limitations/implications: There are still certain shortages of industrial
applications, namely the limits of economic cycle times for economical mass production
which needs further research activities in these fields.
Practical implications: Since both the materials mentioned above and the forming
processes usually applied, furthermore the available benefits are extremely important for the
automotive industry these results have significant practical involvement.
Originality/value: The applied research methods and the introduced new findings will
show the originality of the paper.
El análisis reticular de coincidencias
Authors: Escobar Modesto , Tejero Carlos
Published: January 2018

El propósito de este artículo es la propuesta de un nuevo marco para el estudio de las estructuras de datos basado en la combinación de diversos análisis multivariantes y de redes sociales. Mediante estas técnicas se obtienen qué sucesos son los más frecuentes en un conjunto de escenarios y con qué otros sucesos tienden a ocurrir. A este respecto pueden distinguirse diversos gradientes de coincidencias entre los sucesos estudiados, que van desde la nula coincidencia hasta la coincidencia total pasando por las coincidencias estadísticamente probables con nivel de confianza prefijado. La estructura de aparición del conjunto de los sucesos estudiados conforme al gradiente de coincidencia seleccionado puede ser convenientemente representada mediante un grafo. Además de sus fundamentos, se presentan tres programas gratuitos con los que cualquier usuario podría aplicarlo: coin, netcoin y webcoin. Este tipo de procedimiento puede ser aplicado al análisis exploratorio de cuestionarios, al estudio de redes semánticas, a la revisión de bases de datos e incluso a la comparación de distintas técnicas de análisis estadísticos de interdependencia, al hacer uso de métodos factoriales, clasificatorios y distintos modelos de representación de grafos basados en fuerzas de atracción-repulsión como los de Fruchterman-Reingold y Kamada-Kawai.The goal of this paper is the proposal of a new framework for the study of data structures based on the combination of several types of multivariate and social network analysis. By means of these techniques we obtain the most frequent events in a given set of scenarios as well as those events that tend to occur with them. In this respect we can define several coincidence gradients for the events under study. Ranging from zero to total coincidence and passing through statistically probable coincidences with predetermined confidence levels. The appearance structure of the set of events studied according to the selected coincidence gradient can be conveniently represented by a graph. In addition to its rationale, three free software programs are shown so that any user could apply this framework: coin, netcoin and webcoin. This type of procedure can be applied to the exploratory analysis of questionnaires, to the study of semantic networks, to the revision of databases and even to the comparison of different techniques of statistical analysis of interdependence. This is made posible by using factorial and classificatory methods and different methods for representing graphs based on attraction-repulsion forces, like those of Fruchterman-Reingold and Kamada-Kawai.
Madres e hijas: ¿Se hereda el modelo de maternidad?
Authors: De Linos Escario Almudena
Published: January 2018

En el presente trabajo se analiza la posible transferencia del modelo de maternidad entre madres e hijas y los factores de los que puede depender dicha influencia. Se ha llevado a cabo una investigación cualitativa con mujeres con hijos y sus madres y se confirma, en los casos analizados, la hipótesis de partida de que la influencia es positiva. Sin embargo, ello no significa que siempre la estrategia de la hija siga la misma dirección que la de la madre. Se puede deducir, de los casos analizados, que la dirección que adopte la hija estará determinada por dos factores. El primero sería la contemporaneidad de la estrategia de maternidad seguida por las progenitoras, es decir, lo asumible en términos culturales y sociales que la estrategia seguida por la madre sea para la hija. El segundo factor sería la satisfacción de la vivencia en la infancia de las hijas con la estrategia seguida por sus madres. Para que las hijas sigan una estrategia similar a la de sus madres es necesario que dicha estrategia haya sido satisfactoria para la hija en su infancia y que se considere social y culturalmente acorde al pensamiento del momento.In this paper, it is analysed the possible transfer of motherhood model between mothers and daughters and the factors that may depend on this influence. It has carried out a qualitative research with women with children and their mothers. In the cases analysed, the hypothesis that the influence is positive it has been confirmed. However, this does not mean that the daughter always take the same direction taken by the mother. The direction that takes this influence is due mainly to two factors. On the one hand, to the contemporaneity of maternity strategy followed by the progenitor, and secondly, to the satisfaction of the experience in childhood daughters with the strategy followed by their mothers. For the daughters to follow a similar strategy of their mothers is necessary that this strategy had been successful for the child in its infancy and that socially and culturally was according to the thinking of the moment.
La vida de la infancia en la ciudad y su conflicto con el mundo adulto
Authors: Segovia Collado Chema
Published: January 2018

Este artículo plantea una revisión de la idea del derecho a la ciudad desde la perspectiva de la infancia. La argumentación parte de reconocer una situación de conflicto frente a los adultos que, por diferentes motivos incluso contradictorios, tiende a resolverse en perjuicio de la parte más débil. Tras un encuadre inicial, se reflexiona alrededor de cuatro problemas ante los que el derecho de los niños y las niñas a la ciudad se ve limitado: restricción del uso del espacio urbano, falta de autonomía excusada en la seguridad, crecimiento apartado de la vida en común y falta de participación en decisiones que les afectan. En el análisis de estos problemas, el texto intercala llamadas de atención y posibles cambios de enfoque. Como llamamiento a una mayor confianza y a una apertura comprometida, la reflexión se cierra reivindicando a la infancia como potencial elemento aglomerador de otros colectivos que, sin el suficiente reconocimiento, viven la ciudad en condiciones de desventaja.
Kan eller Skal – hvordan skabes der aktivitet om e-læringsmateriale
Authors: Hartz Christina Biber , Glavind Laura , Jensen Kristian Nøhr
Published: January 2018

Digitale læringsplatforme muliggør deling og genbrug af undervisningsmateriale. Men kan undervisningsmaterialet stå alene på den digitale læringsplatform, og vil undervisere overhovedet bruge materiale udviklet af andre i deres undervisning?Denne artikel undersøger hvordan undervisere kan skabe aktivitet omkring et e-læringsmateriale. Artiklen tager udgangspunkt i et e-læringsforløb i informationssøgning. Forløbet er udarbejdet af biblioteket, og det er placeret på 10 forskellige moduler med 1200 studerende og 100 undervisere.I undersøgelsen anvendes logdata fra professionshøjskolens LMS til at opgøre de studerendes aktivitetsniveau. Forskellen i aktivitet på tværs af holdene undersøges for at finde markante aktivitetsudsving, og undervisere på hold med et højt eller lavt aktivitetsniveau er blevet udvalgt til interview. Gennem interviewene kortlægges det i hvor høj grad underviserne har faciliteret e-læringsmaterialet, hvad de har gjort, og hvorfor de har gjort det. Artiklen peger på at undervisernes værdiladede forventningsafstemning i form af en tydelig italesættelse har betydning for om e-læringsmaterialer på digitale læringsplatforme anvendes af de studerende. Ligeledes har det betydning at underviserne transformerer e-læringsmaterialet til konteksten og bevidst iscenesætter materialet.
À propos des corps, du temps, de l’espace et de la signification
Authors: Ramognino Nicole
Published: January 2018

Lire librement au-delà des intentions, des « stratégies poïétiques » des auteurs ou
du contenu immanent des textes ; sélectionner certaines « traces » et associer des
significations ; cheminement réflexif sur les enjeux sociaux de carrière et sur la
sensibilité des chercheurs. Interrogation sur thématiques récurrentes de l’enquête : la
« longue durée », la territorialisation ou la situation et la question du sens. Deux voies :
la méthode de l’ethnographe, et « l’objet observé ». Éclairer la « plus-value » de
l’observation ethnographique : des corps en activité qui sont observés (l’activité comme
opérateur de production du social), des subjectivités ; traces de processus antérieurs et
latéraux, réactualisés ou non dans la forme d’engagement des acteurs en situation ;
« localisation » des phénomènes, traces significatives pour reconstruire les
représentations, donner sens aux gestes, comportements et activités des acteurs ;
enrichissement de notre expérience. Y a-t-il, alors, analyse sociologique ?
Vendre la banlieue aux Montréalais : discours et stratégies publicitaires, 1950-19701
Authors: Bérubé Harold
Published: January 2018

Cet article traite de la façon dont est mise en marché la banlieue de masse à Montréal dans les années 1950 et 1960. En analysant les publicités relatives aux résidences unifamiliales neuves dans les journaux francophones et anglophone de la métropole, je cherche à mieux comprendre comment évoluent les stratégies publicitaires mises de l’avant et comment se structure l’idéal suburbain qui s’en dégage. L’analyse permet de faire ressortir ce qui constitue une publicité idéaltypique pour la période étudiée, mais également de constater que le discours et les stratégies utilisés se complexifient au fil des ans et convergent d’un groupe linguistique à l’autre, du moins pour ce qui est de leur contenu.
Loss of functional BAP1 augments sensitivity to TRAIL in cancer cells
Authors: Kolluri Krishna Kalyan , Alifrangis Constantine , Kumar Neelam , Ishii Yuki , Price Stacey , Michaut Magali , Williams Steven , Barthorpe Syd , Lightfoot Howard , Busacca Sara , Sharkey Annabel , Yuan Zhenqiang , Sage Elizabeth K , Vallath Sabarinath , Le Quesne John , Tice David A , Alrifai Doraid , von Karstedt Sylvia , Montinaro Antonella , Guppy Naomi , Waller David A , Nakas Apostolos , Good Robert , Holmes Alan , Walczak Henning , Fennell Dean A , Garnett Mathew , Iorio Francesco , Wessels Lodewyk , McDermott Ultan , Janes Samuel M
Published: January 2018

Malignant mesothelioma (MM) is poorly responsive to systemic cytotoxic chemotherapy and invariably fatal. Here we describe a screen of 94 drugs in 15 exome-sequenced MM lines and the discovery of a subset defined by loss of function of the nuclear deubiquitinase BRCA associated protein-1 (BAP1) that demonstrate heightened sensitivity to TRAIL (tumour necrosis factor-related apoptosis-inducing ligand). This association is observed across human early passage MM cultures, mouse xenografts and human tumour explants. We demonstrate that BAP1 deubiquitinase activity and its association with ASXL1 to form the Polycomb repressive deubiquitinase complex (PR-DUB) impacts TRAIL sensitivity implicating transcriptional modulation as an underlying mechanism. Death receptor agonists are well-tolerated anti-cancer agents demonstrating limited therapeutic benefit in trials without a targeting biomarker. We identify BAP1 loss-of-function mutations, which are frequent in MM, as a potential genomic stratification tool for TRAIL sensitivity with immediate and actionable therapeutic implications.
AP4 positively regulates LAPTM4B to promote hepatocellular carcinoma growth and metastasis, while reducing chemotherapy sensitivity
Authors: Meng Yue , Wang Lu , Xu Jianjun , Zhang Qingyun
Published: January 2018

Polymorphisms of the lysosomal‐associated protein transmembrane‐4 beta (LAPTM4B) gene are related to various forms of tumour susceptibility, which led us to hypothesize that some unique transcription factors targeting this polymorphism region may affect the biological function of LAPTM4B in tumour progression. In this study, we found that the transcription factor AP4 directly binds to the polymorphism region of the LAPTM4B gene promoter and induces its transcription. In addition, we demonstrated that AP4 promotes hepatocellular carcinoma (HCC) cell proliferation and metastasis and depresses chemotherapy sensitivity via LAPTM4B by activating the PI3K/AKT signalling pathway and caspase‐dependent pathway. Interestingly, we found that AP4 could not only regulate LAPTM4B by directly binding to the promoter, but also be regulated via a positive feedback mechanism involving LAPTM4B acting on c‐myc. Finally, we showed that AP4 and LAPTM4B are highly coexpressed in HCC tissues, and their coexpression may be a marker of poor prognosis. These findings provide evidence of the expression and functional coupling between AP4 and LAPTM4B and shed light on the regulation of LAPTM4B and its function in liver cancer.
A Year‐Long Comparison of GPS TEC and Global Ionosphere‐Thermosphere Models
Authors: Perlongo N. J. , Ridley A. J. , Cnossen I. , Wu C.
Published: January 2018

The prevalence of GPS total electron content (TEC) observations has provided an opportunity for extensive global ionosphere‐thermosphere model validation efforts. This study presents a year‐long data‐model comparison using the Global Ionosphere‐Thermosphere Model (GITM) and the Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model (TIE‐GCM). For the entire year of 2010, each model was run and compared to GPS TEC observations. The results were binned according to season, latitude, local time, and magnetic local time. GITM was found to overestimate the TEC everywhere, except on the midlatitude nightside, due to high O/N2ratios. TIE‐GCM produced much less TEC and had lower O/N2ratios and neutral wind speeds. Seasonal and regional biases in the models are discussed along with ideas for model improvements and further validation efforts.
Magnetotail Fast Flow Occurrence Rate and Dawn‐Dusk Asymmetry at XGSM ∼ −60 RE
Authors: Kiehas S. A. , Runov A. , Angelopolos V. , Hietala H. , Korovinksiy D.
Published: January 2018

As a direct result of magnetic reconnection, plasma sheet fast flows act as primary transporter of mass, flux, and energy in the Earth's magnetotail. During the last decades, these flows were mainly studied within XGSM>−60RE, as observations near or beyond lunar orbit were limited. By using 5 years (2011–2015) of ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moons Interaction with the Sun) data, we statistically investigate earthward and tailward flows at around 60 RE downtail. A significant fraction of fast flows is directed earthward, comprising 43% (vx>400 km/s) to 56% (vx>100 km/s) of all observed flows. This suggests that near‐Earth and midtail reconnection are equally probable of occurring on either side of the ARTEMIS downtail distance. For fast convective flows (v⊥x>400 km/s), this fraction of earthward flows is reduced to about 29%, which is in line with reconnection as source of these flows and a downtail decreasing Alfvén velocity. More than 60% of tailward convective flows occur in the dusk sector (as opposed to the dawn sector), while earthward convective flows are nearly symmetrically distributed between the two sectors for low AL (>−400 nT) and asymmetrically distributed toward the dusk sector for high AL (<−400 nT). This indicates that the dawn‐dusk asymmetry is more pronounced closer to Earth and moves farther downtail during high geomagnetic activity. This is consistent with similar observations pointing to the asymmetric nature of tail reconnection as the origin of the dawn‐dusk asymmetry of flows and other related observables. We infer that near‐Earth reconnection is preferentially located at dusk, whereas midtail reconnection (X >− 60RE) is likely symmetric across the tail during weak substorms and asymmetric toward the dusk sector for strong substorms, as the dawn‐dusk asymmetric nature of reconnection onset in the near‐Earth region progresses downtail.
The Extending of Observing Altitudes of Plasma and Ion Lines During Ionospheric Heating
Authors: Wu Jun , Wu Jian , Rietveld M. T. , Haggstrom I. , Xu Zhengwen , Zhao Haisheng
Published: January 2018

The ultrahigh‐frequency observation during an ionospheric heating experiment on 11 March 2014 at the European Incoherent Scatter Scientific Association Tromsø site illustrated a remarkable extension of observing altitudes of the enhanced plasma line and the ion line, implying that the enhanced ion acoustic wave and Langmuir wave should satisfy the Bragg condition within the extending altitude range. An analysis shows that the dependence of the wave number of the traveling ion acoustic wave on the profiles of enhanced electron temperature and ion mass, as are expected from the dispersion relation of the ion acoustic wave, leads to the extension of observing altitudes of the enhanced ion line. In addition, the altitude extension of the enhanced plasma line is dependent mainly on the profile of the electron density, although it is not independent of the profile of the electron temperature. Considering a small gradient profile of electron density, however, the enhanced electron temperature, as well as the thermal conduction along the magnetic field, may lead to the altitude extension of the enhanced plasma line.
Experiences, accomplishments, lessons, and challenges of E‐defense—Tests using world's largest shaking table
Authors: Nakashima Masayoshi , Nagae Takuya , Enokida Ryuta , Kajiwara Koichi
Published: January 2018

E‐Defense, which is operated by the Japanese National Research Institute for Earth Science and Disaster Resilience, currently contains the world's largest 3‐dimensional shaking table (size: 20 × 15 m, maximum loading capacity: 12 000 kN). This facility has already implemented over 80 full‐scale or large‐scale experiments since its operation commenced in 2005. During these research activities, E‐Defense has encountered many challenges in the successful execution of various types of experiments within the designed experimental capacity and under the guidance of safe operational management. The experience gained in the past years using E‐Defense has led to the accumulation of knowledge on loading/shaking techniques, measurements for large‐scale specimens, table maintenance and operation, safety management, and specimen construction. This article highlights the major technical issues that have been encountered during the operation of E‐Defense and introduces the solutions that have been achieved. This is followed by brief summaries of some of the major experiments conducted since E‐Defense was commissioned.
Measurement and modeling of water sorption isotherm for salt‐laden autoclaved aerated concrete
Authors: Abuku Masaru , Ogura Daisuke , Hokoi Shuichi
Published: January 2018

The authors reported on the measurement of water sorption isotherms for autoclaved aerated concrete, commonly called “autoclaved lightweight concrete” in Japan, containing aqueous salt (sodium chloride or magnesium chloride) solutions in concentrations ranging from low to saturated with precipitated salt in the material. The important parameters of the salt‐laden porous materials were clearly defined. The measurement results confirmed the significant impacts of salt on the sorption isotherms, particularly at high salt concentrations. The measured sorption isotherms were modeled with the existing model that considers the vapor pressure depression and the density of the salt solution. The results showed that the differences between the measurements and the model increased with increasing amount of precipitated salt in the material. Therefore, a modified model for predicting the water sorption isotherm for a porous material containing not only a salt solution but also precipitated salt was proposed and discussed. The modified model showed better agreement with the measurements.
Development of heat pump model based on outlet temperature of heat medium
Authors: Togashi Eisuke
Published: January 2018

In this paper, we describe a new heat pump calculation model that achieves the following objectives: (i) demonstrates the influences of temperature, flow rate, and load ratio of the heating medium on the system; (ii) describes the system characteristics affected by the heat medium outlet temperature; (iii) analytically solves system equations without iterative convergence calculations; (iv) implements a small number of explanatory variables, thereby allowing the shape of the characteristic expression to be easily overlooked; and (v) is generalizable because the explanatory variables are dimensionless. The parameters of the developed model for the ground source heat pump were estimated, and the calculation results were compared with those of the model developed using the LCEM tool. The ground source heat pump model was developed with a cooling water pump and a ground heat exchanger. The relationship between the cooling water flow rate, partial load rate, and system efficiency was calculated. It was confirmed that the trade‐off between the power consumption by the heat pump and the cooling water pump can be described using the cooling water flow rate.
Bayesian Decision‐Making with Application to Resource Allocation
Authors: Betancourt Brenda , Steorts Rebecca C.
Published: January 2018

In decision theory, we start with the end in mind – how does one use inference results to make decisions and what consequences do these decisions have? Such statistical decision problems are becoming increasingly important as data are readily available at our fingertips. We outline the fundamental ideas of loss for decision theoretic tasks, Bayesian point estimation, and both frequentist and Bayesian risks. We focus on the Bayesian approach to statistical decision‐making and show the connections to Bayesian point estimation, while also contrasting it with the frequentist approach. We illustrate the decision theoretic tasks on a resource allocation problem where one is faced with estimating the proportion of individuals affected by a disease. By performing Bayesian sensitivity analysis, we explore several solutions to this problem and discuss their practical implications.
Extreme Events Modeling in Energy Companies
Authors: Bousquet Nicolas
Published: January 2018

This article presents different methodologies used by energy companies to model extreme events, especially natural hazards, a common requirement for these industries with strong social and environmental responsibilities.
Minimal Sufficient Balance – A Better Alternative to Minimization for Randomized Controlled Trials
Authors: Zhao Wenle
Published: January 2018

When stratified randomization fails owing to the large number of strata, the minimization method proposed by Taves, Pocock, and Simon in the 1970s becomes the only effective method for balancing multiple baseline covariates across treatment groups in clinical trials. It uses deterministic or biased‐coin assignments to reduce the sum of treatment imbalances in the margins of multiple baseline covariates, no matter how small these imbalances are. Controversies over the use of minimization in randomized controlled trials focus on the lack of allocation randomness, which is the root of selection bias. Theminimal sufficient balancestrategy recently proposed by Zhaoet al. uses biased‐coin treatment assignments only when the baseline covariate imbalance is serious, and such a biased‐coin assignment can meaningfully reduce the imbalance. Otherwise, the complete random treatment assignment is applied in order to minimize treatment allocation predictability.
A Type of 1 nm Molybdenum Carbide Confined within Carbon Nanomesh as Highly Efficient Bifunctional Electrocatalyst
Authors: Cheng Zhihua , Fu Qiang , Han Qing , Xiao Yukun , Liang Yuan , Zhao Yang , Qu Liangti
Published: January 2018

Highly efficient platinum‐alternative bifunctional catalysts by using abundant non‐noble metal species are of critical importance to the future sustainable energy reserves. Unfortunately, current electrocatalysts toward hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) are far from satisfactory because of lacking reasonable design and assembly protocols. A type of 1‐nm molybdenum carbide nanoparticles confined in mesh‐like nitrogen‐doped carbon (Mo2C@NC nanomesh) with high specific surface area is reported here. In addition to the superior ORR performance comparable to platinum, the catalyst offers a high HER activity with small Tafel slope of 33.7 mV dec−1 and low overpotential of 36 mV to reach −10 mA cm−2. Theoretical calculations indicate that the active sites of the catalyst are mainly located at Mo atoms adjacent to the N‐doped carbon layer, which contributes the high HER activity. These findings show the great potential of Mo2C species in wide electrocatalysis applications.
Thermally Activated Delayed Fluorescence Conjugated Polymers with Backbone‐Donor/Pendant‐Acceptor Architecture for Nondoped OLEDs with High External Quantum Efficiency and Low Roll‐Off
Authors: Yang Yike , Wang Shumeng , Zhu Yunhui , Wang Yanjie , Zhan Hongmei , Cheng Yanxiang
Published: January 2018

Most thermally activated delayed fluorescence (TADF) emitters have to be doped in the host for fabricating efficient organic light‐emitting diodes (OLEDs) and always suffer from quick efficiency roll‐off at high brightness, which severely affect their commercial application in display and lighting fields. In the work, a series of the polymers are synthesized by copolymerization of two carbazole monomers and one acridine derivative monomer containing benzophenone acceptor group. The obtained polymers therefore possess a conjugated backbone with carbazole/acridine moieties and benzophenone pendant to form the twisted donor/acceptor structure. Consequently, the TADF features inherited from the acridine derivative are maintained and improved by managing the content of acridine derivative monomer in the polymers. Solution‐processed OLEDs obtained from using neat polymer films exhibit comparable performance with organic TADF small molecules, achieving a maximum external quantum efficiency (EQE) of 18.1% and a very slow roll‐off with EQE of 17.8% at the luminance of 1000 cd m−2.
3D Printing of Materials with Tunable Failure via Bioinspired Mechanical Gradients
Authors: Kokkinis Dimitri , Bouville Florian , Studart André R.
Published: January 2018

Mechanical gradients are useful to reduce strain mismatches in heterogeneous materials and thus prevent premature failure of devices in a wide range of applications. While complex graded designs are a hallmark of biological materials, gradients in manmade materials are often limited to 1D profiles due to the lack of adequate fabrication tools. Here, a multimaterial 3D‐printing platform is developed to fabricate elastomer gradients spanning three orders of magnitude in elastic modulus and used to investigate the role of various bioinspired gradient designs on the local and global mechanical behavior of synthetic materials. The digital image correlation data and finite element modeling indicate that gradients can be effectively used to manipulate the stress state and thus circumvent the weakening effect of defect‐rich interfaces or program the failure behavior of heterogeneous materials. Implementing this concept in materials with bioinspired designs can potentially lead to defect‐tolerant structures and to materials whose tunable failure facilitates repair of biomedical implants, stretchable electronics, or soft robotics.
Reversible CO2 Addition to a Si=O Bond and Synthesis of a Persistent SiO2–CO2 Cycloadduct Stabilized by a Lewis Donor–Acceptor Ligand
Authors: Rodriguez Ricardo , Alvarado‐Beltran Isabel , Saouli Jérémy , Saffon‐Merceron Nathalie , Baceiredo Antoine , Branchadell Vicenç , Kato Tsuyoshi
Published: January 2018

The donor‐stabilized sila‐β‐lactone 1 reacts with CO2 via a remarkable reversible [2+2]‐cycloaddition reaction to form the spiro‐cyclic silicon carbonate derivative 2. Furthermore, photolysis of 2 under pressure of CO2 affords the first persistent SiO2–CO2 cycloadduct 3, presenting a Si2O4‐like structure, which is stabilized by a Lewis donor–acceptor type ligand. As predicted by theoretical calculations, in marked contrast to the thermodynamically stable SiO2 dimer, the SiO2–CO2 mixed cycloadduct 3 is labile and readily releases CO2.
Silver(I)‐Catalyzed Widely Applicable Aerobic 1,2‐Diol Oxidative Cleavage
Authors: Zhou Zhong‐zhen , Liu Mingxin , Lv Leiyang , Li Chao‐Jun
Published: January 2018

The oxidative cleavage of 1,2‐diols is a fundamental organic transformation. The stoichiometric oxidants that are still predominantly used for such oxidative cleavage, such as H5IO6 , Pb(OAc)4 , and KMnO4 , generate stoichiometric hazardous waste. Herein, we describe a widely applicable and highly selective silver(I)‐catalyzed oxidative cleavage of 1,2‐diols that consumes atmospheric oxygen as the sole oxidant, thus serving as a potentially greener alternative to the classical transformations.
Palladium‐Catalyzed Asymmetric Aminohydroxylation of 1,3‐Dienes
Authors: Shen Hong‐Cheng , Wu Yu‐Feng , Zhang Ying , Fan Lian‐Feng , Han Zhi‐Yong , Gong Liu‐Zhu
Published: January 2018

A PdII‐catalyzed asymmetric aminohydroxylation of 1,3‐dienes with N‐tosyl‐2‐aminophenols was developed by making use of a chiral pyridinebis(oxazoline) ligand. The highly regioselective reaction provides direct and efficient access to chiral 3,4‐dihydro‐2H‐1,4‐benzoxazines in high yield and enantioselectivity (up to 96:4 e.r.). The reaction employs readily available N‐tosyl‐2‐aminophenols as a unique aminohydroxylation reagent and is complementary to known asymmetric aminohydroxylation methods.
Fused‐Ring Formation by an Intramolecular “Cut‐and‐Sew” Reaction between Cyclobutanones and Alkynes
Authors: Deng Lin , Jin Likun , Dong Guangbin
Published: January 2018

The development of a catalytic intramolecular “cut‐and‐sew” transformation between cyclobutanones and alkynes to construct cyclohexenone‐fused rings is described herein. The challenge arises from the need for selective coupling at the more sterically hindered proximal position, and can be addressed by using an electron‐rich, but less bulky, phosphine ligand. The control experiment and 13C‐labelling study suggest that the reaction may start with cleavage of the less hindered distal C−C bond of cyclobutanones, followed by decarbonylation and CO reinsertion to enable Rh insertion at the more hindered proximal position.
Fe2Si5N8: Access to Open‐Shell Transition‐Metal Nitridosilicates
Authors: Bielec Philipp , Janka Oliver , Block Theresa , Pöttgen Rainer , Schnick Wolfgang
Published: January 2018

Highly condensed nitridosilicates doped with Eu2+ or Ce3+ play an important role in saving energy by converting the blue light of (In,Ga)N‐LEDs. Although nitridosilicates are known for great structural variety based on covalent anionic Si‐N networks, elemental variety is restricted. Presenting a significant extension of the latter, this work describes a general access to open‐shell transition‐metal nitridosilicates. As a proof‐of‐principle, the first iron nitridosilicate, namely Fe2Si5N8, was prepared by exchanging Ca2+ in α‐Ca2Si5N8 applying a FeCl2 melt (salt metathesis). The title compound was analyzed by powder X‐ray diffraction, EDX, ICP‐OES, combustion analysis, TG/DSC, Mössbauer spectroscopy and magnetic susceptibility measurements. Furthermore, the structure of α‐Ca2Si5N8 was determined at 1073 and 1173 K confirming the anionic network of α‐Ca2Si5N8 providing possible migration pathways for the ion‐exchange reaction.
Correlation of simulation/finite element analysis to the separation of intrinsically magnetic spores and red blood cells using a microfluidic magnetic deposition system
Authors: Sun Jianxin , Moore Lee , Xue Wei , Kim James , Zborowski Maciej , Chalmers Jeffrey J.
Published: January 2018

Magnetic separation of cells has been, and continues to be, widely used in a variety of applications, ranging from healthcare diagnostics to detection of food contamination. Typically, these technologies require cells labeled with antibody magnetic particle conjugate and a high magnetic energy gradient created in the flow containing the labeled cells (i.e., a column packed with magnetically inducible material), or dense packing of magnetic particles next to the flow cell. Such designs, while creating high magnetic energy gradients, are not amenable to easy, highly detailed, mathematic characterization. Our laboratories have been characterizing and developing analysis and separation technology that can be used on intrinsically magnetic cells or spores which are typically orders of magnitude weaker than typically immunomagnetically labeled cells. One such separation system is magnetic deposition microscopy (MDM) which not only separates cells, but deposits them in specific locations on slides for further microscopic analysis. In this study, the MDM system has been further characterized, using finite element and computational fluid mechanics software, and separation performance predicted, using a model which combines: 1) the distribution of the intrinsic magnetophoretic mobility of the cells (spores); 2) the fluid flow within the separation device; and 3) accurate maps of the values of the magnetic field (max 2.27 T), and magnetic energy gradient (max of 4.41 T2/mm) within the system. Guided by this model, experimental studies indicated that greater than 95% of the intrinsically magnetic Bacillus spores can be separated with the MDM system. Further, this model allows analysis of cell trajectories which can assist in the design of higher throughput systems.
The winter blues: Real depression or just down in the dumps? Pay attention, whatever it is
Authors: Knopf Alison
Published: January 2018

Sometimes, seasonal affective disorder (SAD) — as the most serious manifestation of the winter blues is officially known — is clinical depression. But sometimes it's not a clinical problem, it's a weather one. It's just reality: days are shorter and nights are longer, and in some parts of the world, life is colder.
Implications of microwave drying using 915 MHz frequency on rice physicochemical properties
Authors: Smith Deandrae L. , Atungulu Griffiths G. , Sadaka Sammy , Rogers Stephen
Published: January 2018

Background and objectives

High moisture content (MC) rough rice was dried using an industrial microwave (MW) operated at a frequency of 915 MHz, and the impacts of the drying on the rice physicochemical properties were investigated. The treatments were performed at MW power levels 5, 10, and 15 kW, treatment durations 4, 6, and 8 min and for rice at initial MC of 24% (w.b.) and bed thicknesses 5, 10, and 15 cm. Near infrared spectroscopy and a rapid visco‐analyzer were used to assess the milled rice protein content, surface lipid content (SLC), total color difference (TCD), and rice peak and final viscosities.

Findings

The effect of increasing MW specific energy was statistically significant for all of the responses studied. Increasing MW specific energy resulted in an increase in measured rice SLC, protein content, and final and peak viscosities. Responses increased to a maximum then decreased at specific energies over 800 kJ/kg‐grain. The opposite profile was true for TCD. The TCD decreased as a result of increasing MW specific energy to a trough at 533.33 kJ/kg‐grain then increased at specific energies over 600 kJ/kg‐grain. The effect of varying rice bed thicknesses was not statistically significant.

Conclusions

It is vital to select appropriate MW specific energy to maintain the rice physicochemical properties.

Significance and novelty

Using MW heating with a frequency at 915 MHz provides new avenues to scale up the MW heating technology for rice drying; this may allow rapid, one‐pass rice drying while maintaining important quality characteristics.
Variation in asparagine concentration in Nebraska wheat
Authors: Navrotskyi Sviatoslav , Baenziger Peter Stephen , Regassa Teshome , Guttieri Mary J. , Rose Devin J.
Published: January 2018

Background and objectives

Acrylamide can be formed from asparagine during baking of wheat products. Therefore, evaluation of different wheat cultivars and environmental conditions is needed to assess the potential risk of acrylamide formation in baked products made from Nebraska wheats. Three widely grown wheat cultivars (Goodstreak, Camelot, Freeman) and seven experimental lines were grown at five locations in 2014. Due to the large environmental effect on asparagine concentration, the named cultivars were also evaluated at twelve locations in 2016.

Findings

Asparagine concentration varied widely among samples (200–1,100 mg/kg). In 2014, the highest concentration of asparagine was measured in samples grown at a location where delayed harvest resulted in excess solar radiation. In 2016, the highest asparagine concentration was measured in wheat grains grown in a location that experienced high disease pressure. In pairwise comparisons among all 17 locations sampled, asparagine was generally lower in Freeman compared with Goodstreak and Camelot. Asparagine concentration was positively correlated with kernel size and weight (r = .37; p = .03).

Conclusions

The major differences in asparagine concentration were due to growing environment, although the cultivar Freeman may be a low asparagine accumulating genotype.

Significance and novelty

Conditions that are associated with elevated asparagine include delayed harvest, disease pressure, and larger kernel size.
Interrogating Protein Phosphatases with Chemical Activity Probes
Authors: Casey Garrett R. , Stains Cliff I.
Published: January 2018

Protein phosphatases, while long overlooked, have recently become appreciated as drivers of both normal‐ and disease‐associated signaling events. As a result, the spotlight is now turning torwards this enzyme family and efforts geared towards the development of modern chemical tools for studying these enzymes are well underway. This Minireview focuses on the evolution of chemical activity probes, both optical and covalent, for the study of protein phosphatases. Small‐molecule probes, global monitoring of phosphatase activity through the use of covalent modifiers, and targeted fluorescence‐based activity probes are discussed. We conclude with an overview of open questions in the field and highlight the potential impact of chemical tools for studying protein phosphatases.
9,9′‐Bifluorenylidene‐Core Perylene Diimide Acceptors for As‐Cast Non‐Fullerene Organic Solar Cells: The Isomeric Effect on Optoelectronic Properties
Authors: Zhao Yuan , Wang Huan , Xia Shengpeng , Zhou Feng , Luo Zhenghui , Luo Jiajia , He Feng , Yang Chuluo
Published: January 2018

Two different non‐fullerene small‐molecule acceptors, m‐PIB and p‐PIB, based on 9,9′‐bifluorenylidene (BF) and perylene diimide (PDI) were designed and synthesized. Four β‐substituted PDIs were linked to BF in different positions. Based on DFT analysis, derivative p‐PIB exhibited reduced intramolecular twisting between the PDI moieties, more delocalized wave function, and sufficiently wider π‐electron delocalization than that of m‐PIB. The absorption ability of p‐PIB was enhanced due to increased intermolecular interactions. By blending p‐PIB with poly{4,8‐bis[5‐(2ethylhexyl)thiophen‐2‐yl]benzo[1,2‐b:4,5‐b′]dithiophene‐co‐3‐fluorothieno[3,4‐b]‐thiophene‐2‐carboxylate} (PTB7‐Th), organic solar cells (OSCs) based on p‐PIB obtained a maximum power conversion efficiency of 5.95 % without any treatments. Due to the improved and balanced hole and electron mobilities, the short‐circuit current and fill factor of OSCs based on PTB7‐Th and p‐PIB were significantly increased. The AFM and TEM results revealed that the PTB7‐Th:p‐PIB film had favorable nanoscale phase separation and formed a bicontinuous interpenetrating network.
Organotin Dyes Bearing Anionic Boron Clusters as Cell‐Staining Fluorescent Probes
Authors: Muñoz‐Flores Blanca M. , Cabrera‐González Justo , Viñas Clara , Chávez‐Reyes Arturo , Dias H. V. Rasika , Jiménez‐Pérez Víctor M. , Núñez Rosario
Published: January 2018

Within the cell nucleus, in the nucleoli, ribosomal RNAs are synthesized and participate in several biological processes. To better understand nucleoli‐related processes, their visualization is often required, for which specific markers are needed. Herein, we report the design of novel fluorescent organotin compounds derived from 4‐hydroxy‐N′‐((2‐hydroxynaphthalen‐1‐yl)methylene)benzohydrazide and their cytoplasm and nucleoli staining of B16F10 cells in vitro. Tin compounds bearing an aliphatic carbon chain (‐C12H25) and an electron‐donating group (‐OH) were prepared, and the latter could be derivatized to bear the boron cluster anions [B12H12]2− and [3,3′‐Co(1,2‐C2B9H11)2]− (COSAN). All of the conjugates have been fully characterized and their luminescence properties have been assessed. In general, they show good quantum yields in solution (24–49 %), those for the COSAN derivatives being lower. Remarkably, the linking of [B12H12]2− and COSAN to the complexes made them more soluble, without being detrimental to their luminescence properties. Living B16F10 cells were treated with all of the compounds to determine their fluorescence staining properties; the compounds bearing the aliphatic chain showed a reduced staining capacity due to the formation of aggregates. Notably, the complexes bearing different boron clusters showed different staining effects; those bearing [B12H12]2− showed extraordinary staining of the nucleoli and cytoplasm, whereas those bearing COSAN were only detected in the cytoplasm. The remarkable fluorescence staining properties shown by these organotin compounds make them excellent candidates for fluorescence bioimaging in vitro.
A Combined Photochemical and Multicomponent Reaction Approach to Precision Oligomers
Authors: Konrad Waldemar , Bloesser Fabian R. , Wetzel Katharina S. , Boukis Andreas C. , Meier Michael A. R. , Barner‐Kowollik Christopher
Published: January 2018

We introduce the convergent synthesis of linear monodisperse sequence‐defined oligomers through a unique approach, combining the Passerini three‐component reaction (P‐3CR) and a Diels–Alder (DA) reaction based on photocaged dienes. A set of oligomers is prepared resting on a Passerini linker unit carrying an isocyano group for chain extension by P‐3CR and a maleimide moiety for photoenol conjugation enabling a modular approach for chain growth. Monodisperse oligomers are accessible in a stepwise fashion by switching between both reaction types. Employing sebacic acid as a core unit allows the synthesis of a library of symmetric sequence‐defined oligomers. The oligomers consist of alternating P‐3CR and photoblocks with molecular weights up to 3532.16 g mol−1, demonstrating the successful switching from P‐3CR to photoenol conjugation. In‐depth characterization was carried out including size‐exclusion chromatography (SEC), high‐resolution electrospray ionization mass spectrometry (ESI‐MS) and NMR spectroscopy, evidencing the monodisperse nature of the precision oligomers.
Fixing the Conformation of Calix[4]arenes: When Are Three Carbons Not Enough?
Authors: Matthews Susan E. , Cecioni Samy , O'Brien John E. , MacDonald Colin J. , Hughes David L. , Jones Garth A. , Ashworth Stephen H. , Vidal Sébastien
Published: January 2018

Calix[4]arenes are unique macrocycles that through judicious functionalisation at the lower rim can be either fixed in one of four conformations or remain conformationally flexible. Introduction of propynyl or propenyl groups unexpectedly provides a new possibility; a unidirectional conformational switch, with the 1,3‐alternate and 1,2‐alternate conformers switching to the partial cone conformation, whilst the cone conformation is unchanged, under standard experimental conditions. Using 1H NMR kinetic studies, rates of switching have been shown to be dependent on the starting conformation, upper‐rim substituent, where reduction in bulk enables faster switching, solvent and temperature with 1,2‐alternate conformations switching fastest. Ab initio calculations (DFT) confirmed the relative stabilities of the conformations and point towards the partial cone conformer being the most stable of the four. The potential impact on synthesis through the “click” reaction has been investigated and found not to be significant.
Synthesis of Multifunctional Spirocyclic Azetidines and Their Application in Drug Discovery
Authors: Kirichok Alexander A. , Shton Irina O. , Pishel Irina M. , Zozulya Sergey A. , Borysko Petro O. , Kubyshkin Vladimir , Zaporozhets Olha A. , Tolmachev Andrei A. , Mykhailiuk Pavel K.
Published: January 2018

The synthesis of multifunctional spirocycles was achieved from common cyclic carboxylic acids (cyclobutane carboxylate, cyclopentane carboxylate, l‐proline, etc.). The whole sequence included only two chemical steps—synthesis of azetidinones, and reduction into azetidines. The obtained spirocyclic amino acids were incorporated into a structure of the known anesthetic drug Bupivacaine. The obtained analogues were more active and less toxic than the original drug. We believe that this discovery will lead to a wide use of spirocyclic building blocks in drug discovery in the near future.
Mechanochromic Polymers That Turn Green Upon the Dissociation of Diarylbibenzothiophenonyl: The Missing Piece toward Rainbow Mechanochromism
Authors: Ishizuki Kuniaki , Oka Hironori , Aoki Daisuke , Goseki Raita , Otsuka Hideyuki
Published: January 2018

Mechanochromic polymers, that is, polymers sensitive to mechanical impact, promise great potential for applications in damage sensors. In particular, radical‐type mechanochromic polymers, which produce colored radical species in response to mechanical stress, may enable not only the visualization of mechanical stress, but also its quantitative evaluation by electron paramagnetic resonance analysis. Herein, a radical‐type mechanochromic polymer that exhibits a color change from white to green upon dissociation of a diarylbibenzothiophenonyl moiety at the mid‐point of a polystyrene chain is presented, and its mechanochromic behavior is examined. Mechanochromic materials that show a variety of colors (“rainbow colors”) in response to mechanical stress were prepared by simply mixing radical‐type mechanochromic polymers of primary colors.