bluuebunny/crossref_metadata_2025 huggingface dataset:
Interstitial P‐Doped CdS with Long‐Lived Photogenerated Electrons for Photocatalytic Water Splitting without Sacrificial Agents
Authors: Shi Rui , Ye Hui‐Fang , Liang Fei , Wang Zhuan , Li Kai , Weng Yuxiang , Lin Zheshuai , Fu Wen‐Fu , Che Chi‐Ming , Chen Yong
Published: December 2017

Photocatalytic hydrogen evolution from pure water is successfully realized by using interstitial P‐doped CdS with rich S vacancies (CdS‐P) as the photocatalyst in the absence of any electron sacrificial agents. Through interstitial P doping, the impurity level of S vacancies is located near the Fermi level and becomes an effective electron trap level in CdS‐P, which can change dynamic properties of photogenerated electrons and thus prolong their lifetimes. The long‐lived photogenerated electrons are able to reach the surface active sites to initiate an efficient photocatalytic redox reaction. Moreover, the photocatalytic activity of CdS‐P can be further improved through the loading of CoP as a cocatalyst.
Nanocasting of Superparamagnetic Iron Oxide Films with Ordered Mesoporosity
Authors: Kraffert Katrin , Kabelitz Anke , Siemensmeyer Konrad , Schmack Roman , Bernsmeier Denis , Emmerling Franziska , Kraehnert Ralph
Published: December 2017

Maghemite and magnetite show superparamagnetic behavior when synthesized in a nanostructured form. The material's inducible magnetization enables applications ranging from contrast enhancing agents for magnetic resonance imaging to drug delivery systems, magnetic hyperthermia, and separation. Superparamagnetic iron oxides with templated porosity have been synthesized so far only in the form of hard‐templated powders, where silicon retained from the template severely degrades the material's magnetic properties. Here, for the first time, the synthesis of superparamagnetic iron oxides with soft‐templated mesopore structure is reported. The synthesis of nanostructured maghemite and magnetite films succeeds using micelles of amphiphilic block‐copolymers as templates. A thermal treatment of the initially formed mesoporous ferrihydrite in nitrogen produces maghemite, which can be partly reduced to magnetite via thermal treatment in hydrogen while retaining the templated mesopore structure. The resulting materials feature a unique combination of high surface area, controlled pore diameter, and tunable magnetic properties.
An Integrative Mesh with Dual Wettable On–Off Switch of Water/Oil
Authors: Feng Shile , Xing Yan , Deng Siyan , Shang Weifeng , Li Dan , Zhang Miaoxin , Hou Yongping , Zheng Yongmei
Published: December 2017

Smart dual selective water/oil separation mode appears on an integrative mesh, which is fabricated via combined anodic oxidation and cathodic electrode‐deposition methods. Due to the different transport directions of oil and water, oil–water mixture can be separated completely using tailor‐made device. Extrusion pressure, acting as a critical pressure that depends on liquid surface tension, substrate microstructures, and wetting properties, can be a major factor to determine the passing or blocking mode. These remarkable water/oil separation properties of the integrative mesh can bring about novel applications in fluid rectifying, microchemical reaction manipulation, advanced separation, biomedical materials, purifying industrial wastewater, etc.
Ultrastretchable Strain Sensors Using Carbon Black‐Filled Elastomer Composites and Comparison of Capacitive Versus Resistive Sensors
Authors: Shintake Jun , Piskarev Yegor , Jeong Seung Hee , Floreano Dario
Published: December 2017

The advent of soft robotics has led to the development of devices that harness the compliance and natural deformability of media with nonlinear elasticity. This has led to a need of batch‐manufacturable soft sensors that can sustain large strains and maintain kinematic compatibility with the systems they track. In this article, an approach to address this challenge is presented with highly stretchable strain sensors that can operate at strains up to 500%. The sensors consist of a carbon black‐filled elastomer composite that is batch manufactured using film‐casting techniques and CO2 laser ablation. This process facilitates the rapid multilayered fabrication of both capacitive and resistive sensing elements. When measuring capacitance, these sensors exhibit high linearity (R2 = 0.9995), low hysteresis under cyclic loading with varying strain amplitude (50–500%), and high repeatability (≥104 cycles). The sensors possess gauge factors of 0.83–0.98 in capacitive mode and 1.62–3.37 in resistive mode.
Trap Assisted Bulk Silicon Photodetector with High Photoconductive Gain, Low Noise, and Fast Response by Ag Hyperdoping
Authors: Qiu Xiaodong , Yu Xuegong , Yuan Shuai , Gao Yuhan , Liu Xuemei , Xu Yang , Yang Deren
Published: December 2017

Silicon‐based photoconductors, with their low cost, high sensitivity, and complementary metal–oxide–semiconductor (CMOS) compatibility, have great potential for high‐resolution imaging, light‐activated switching, and single‐photon counting. However, they usually suffer from a large dark leakage current and a long response time, which greatly limits their applications. Here, a high‐performance bulk silicon photodetector is fabricated working at room temperature with a broad spectral response range from 300 to 1200 nm through silver (Ag) hyperdoping. The detector shows a low dark current of 3.8 × 10−7 A cm−2 and a high external quantum efficiency of 266.0% for 800 nm at −1 V reverse bias, indicating a photoconductive gain. Moreover, the Si:Ag photodetector has a very low noise and a high detectivity (≈1.84 × 1012 Jones at −1 V), and meanwhile exhibits a rapid response speed with the rise time of 12.5 µs and fall time of 15.9 µs. By combining with the deep level transient spectrum measurements, it is believed that the operating mechanism of the detector is based on the electron traps with an average energy level of Ec– 0.28 eV induced by the Ag hyperdoping. These results are of significance for the fabrication of silicon‐based photodetectors with high performances.
Perovskite Excitonics: Primary Exciton Creation and Crossover from Free Carriers to a Secondary Exciton Phase
Authors: Sarritzu Valerio , Sestu Nicola , Marongiu Daniela , Chang Xueqing , Wang Qingqian , Loi Maria Antonietta , Quochi Francesco , Saba Michele , Mura Andrea , Bongiovanni Giovanni
Published: December 2017

Understanding exciton formation is of fundamental importance for emerging optoelectronic materials, like hybrid organic–inorganic perovskites, as excitons are the lowest‐energy photoexcitations in semiconductors, are electrically neutral, and do not directly contribute to charge transport, but can emit light more efficiently than free carriers. However, despite the increasing attention toward these materials, experimental results on the processes of formation of an exciton population in perovskites are still elusive. Here, an ultrafast differential photoluminescence technique is presented that is able to track the kinetics of exciton formation and dissociation in CH3NH3PbBr3. Data show the presence of geminate excitons, i.e., primary excitons directly created upon photon absorption, and their dissociation into free electron–hole pairs. The formation is demonstrated of a secondary exciton phase through pairing of the initial population of free carriers. The analysis of the generation of secondary excitons provides an estimate of the Langevin factor, the parameter governing the charge‐pairing rate. Understanding and controlling the formation of a bright exciton population instead of a highly conductive free carrier population may help to design new hybrid perovskite materials with tailored optoelectronic functionalities.
Enhanced Two‐Photon‐Pumped Emission from In Situ Synthesized Nonblinking CsPbBr3/SiO2 Nanocrystals with Excellent Stability
Authors: Hu Zhiping , Liu Zhengzheng , Bian Yao , Li Shiqi , Tang Xiaosheng , Du Juan , Zang Zhigang , Zhou Miao , Hu Wei , Tian Yuxi , Leng Yuxin
Published: December 2017

Perovskites have emerged as a class of cutting‐edge photovoltaic and light‐emitting materials. However, poor stability due to high moisture sensitivity and undesirable blinking severely limits their further application. Here, to solve these problems without destroying optoelectronic performance, a simple process for the fabrication of nonblinking CsPbBr3 quantum dots (QDs) is investigated. By embedding CsPbBr3 QDs into waterless silica spheres, the blinking of QDs can be strikingly suppressed, with an effective improvement of the moisture resistance and enhanced photostability. The silica sphere can also prevent anion exchange of different halide elements between perovskite QDs. Ultrastable amplified spontaneous emission (ASE) from QDs/SiO2 with no degradation for at least 12 h is observed under continuous laser irradiation (4 × 107 continuous intense laser shots), with almost no ASE degradation evident after 60 d of storage under ambient conditions. Most notably, the ASE threshold (Pth) of CsPbBr3 QDs is decreased by 50% and the relative efficiency increased by 388%. The perovskite QDs coated by the waterless SiO2 shell provide a novel platform for realizing perovskite nanomaterials with improved operational stability, nonblinking properties, and enhanced emission all at the same time, which is especially attractive for photovoltaic and light‐emitting device applications.
Magnetochromic Photonic Hydrogel for an Alternating Magnetic Field‐Responsive Color Display
Authors: Wang Wentao , Fan Xiaoqiao , Li Feihu , Qiu Jinjing , Umair Malik Muhammad , Ren Wenchen , Ju Benzhi , Zhang Shufen , Tang Bingtao
Published: December 2017

As an external stimulus for stimuli‐responsive chromic materials, a magnetic field has the benefits of contactless control, instant action, and ease of integration into electronic devices. Hence, the development of a magnetically responsive photonic crystal provides a new platform for color displays. However, magnetically controlled display systems have been primarily limited to liquid systems of colloidal crystals; their application to solid chromic systems has been difficult because the ordered array structure is fixed by a polymer network. A novel solid magnetochromic photonic hydrogel is developed that enables colorimetric responses to an alternating magnetic field (AMF). This notable magnetochromic performance is attributed to the superior magnetothermal effect of 1D aggregates of magnetic chains fixed in a thermosensitive hydrogel. The AMF‐responsive magnetic hydrogel exhibits excellent stability for repeated use. This study presents a basis for the development of responsive solid materials with new optical effects for future chromatic applications.
Single Source Precursor Chemical Vapor Decomposition Method to Fabricate Stable, Bright Emissive Aluminum Hydroxide Phosphors for UV‐Pumped White Light‐Emitting Devices
Authors: Chen Bingkun , Xu Xingjian , Zou Shuangyang , Wang Yongtian , Zou Bingsuo , Zhong Haizheng , Rogach Andrey L.
Published: December 2017

Aluminum hydroxides are considered to be a potential abundant, low‐cost blue emissive material to construct UV‐pumped white light‐emitting diodes (WLEDs). In this work, a single‐source precursor chemical vapor decomposition method is adapted to fabricate stable, strongly emissive aluminum hydroxide phosphors with photoluminescence quantum yield of up to 69% in solid state by thermal decomposing aluminum diacetate hydroxide (Al(OH)(Ac)2) at temperatures (260–360 °C) in N2 atmosphere. It exhibits layered, amorphous structure and its emission of aluminum hydroxide is enhanced by electron‐donating surface hydroxyl groups and originates from F+ centers and carbon‐related defects contributing to UV (388 nm) and blue (450–520 nm) spectral regions, respectively. Employing the as‐fabricated aluminum hydroxides as blue phosphor and CuInS2 nanocrystals as red phosphor, high color rendering and high‐efficiency WLEDs with luminous efficiencies up to 37 lm W−1 and high color rendering index of 91 are fabricated. This is the best performance reported so far for aluminum hydroxide based LEDs.
Visible Light‐Induced Synthetic Approach for Selenylative Spirocyclization of N‐Aryl Alkynamides with Molecular Oxygen as Oxidant
Authors: Sahoo Harekrishna , Mandal Anup , Dana Suman , Baidya Mahiuddin
Published: December 2017

A visible light‐induced (blue LED) radical cascade has been devised to effect selenylative spirocyclization of N‐aryl alkynamides at room temperature under oxygen atmosphere and without the aid of external photocatalyst. The protocol is operationally simple, scalable, and offers clean synthesis of 3‐selenospiro[4,5]trienones in high yields (up to 92%). A novel spiro‐ring‐opening strategy has also been accomplished to access fully substituted acryl amides.

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Charge Transfer Kinetics of Photo‐Electrochemical Hydrogen Evolution Improved by Nonstoichiometric Ni‐rich NiOx‐Coated Si Photocathode in Alkaline Electrolyte
Authors: Jung Jin‐Young , Yu Jin‐Young , Yoon Sanghwa , Yoo Bongyoung , Lee Jung‐Ho
Published: December 2017

The integration of electrocatalyst (EC) with light‐absorbing semiconductor photoelectrode is regarded as a representative framework for photoelectrochemical (PEC) devices. When considering the charge transfer pathways, PEC performance is governed by the charge kinetics at the EC/electrolyte and the semiconductor/EC interfaces. Here, systematic investigations are reported, made on the overall kinetics of the PEC hydrogen evolution reaction (HER) in an alkaline electrolyte. A non‐stoichiometric (Ni‐rich) NiOx (x < 1) EC is deposited on a Si photocathode passivated with a SiOx layer. A few distinctive features of the Ni‐rich NiOx film are identified in contrast with the conventional O‐rich NiOy (y ≥ 1) which could lower the series resistance along the charge transfer pathways. The Ni‐rich NiOx is found to possess both NiO and NiNi (by oxygen‐vacancy) bonds, which act as suitable catalytic sites for dissociating water molecules and recombining two hydrogen atoms, respectively. In addition, the Ni‐rich NiOx reveals both n‐type and metallic conduction behavior, a feature that may contribute to lowering bulk resistance as well as tunneling resistance through SiOx layer. As a result, this noble metal‐free EC‐integrated Si photocathode achieves the highest potential of 0.41 V vs. reversible hydrogen electrode to produce a photocurrent density of 10 mA cm2.
A Robust CuCr2O4/SiO2 Composite Photothermal Material with Underwater Black Property and Extremely High Thermal Stability for Solar‐Driven Water Evaporation
Authors: Shi Yusuf , Li Renyuan , Shi Le , Ahmed Elaf , Jin Yong , Wang Peng
Published: December 2017

The design and fabrication of efficient photothermal materials is the key issue in solar‐driven water evaporation. In this work, a robust CuCr2O4/SiO2 composite membrane with outstanding solar‐driven water evaporation performance (1.32 kg m−2 h−1) under one sun irradiation is rationally designed and synthesized by using quartz glass fibrous membrane as supporting matrix and stable CuCr2O4 particles as the active light absorber. Instead of coating a separate layer on top of the support, the CuCr2O4 particles are evenly distributed inside the matrix, which endows the membrane with great mechanical strength and excellent wear and abrasion resistance. The highly porous composite survives 6 atm pressure and retains its performance even after 75% of the membrane is removed by sandpaper. This work also looks into a generally overlooked aspect of wet versus dry state of photothermal material and its implications. Interestingly, the composite possesses a gray color with a high reflectance in dry state but turns into deep black with a low reflectance in wet state due to the decreased subsurface scattering and strong NIR light absorbance of water in wet state. This composite material also possesses excellent thermal stability and thermal shock resistance, making it able to be easily recovered by calcination in air or direct burning in fire for contaminants removal. The results demonstrate that this composite is a competitive photothermal material for practical solar distillation and indicate that the optical properties of material in wet state are more relevant to photothermal material screening and optimization for solar distillation.
Bipolar Magnetic Materials Based on 2D Ni[TCNE] Metal–Organic Coordination Networks
Authors: Chen Yu , Liu Junyi , Sun Qiang , Kawazoe Yoshiyuki , Jena Puru
Published: December 2017

Bipolar magnetic materials can produce alternative spin currents with 100% spin‐polarization by flexible electrical control, showing great potentials in spintronics. Using first‐principles calculations, it is demonstrated that the 2D metal–organic coordination networks, consisting of tetracyanoethylene (TCNE) molecules and Ni atoms, labeled Ni[TCNE], are bipolar magnetic materials showing rich properties: one isomer named a‐Ni[TCNE] is a bipolar magnetic semiconductor (BMS), and another isomer, p‐Ni[TCNE], behaves like a bipolar magnetic metal (BMM). The proper charge transfer leads to the localized spins at the Ni atoms and delocalized spin magnetic moments on the whole structure and the coupling between the localized spins and the itinerant spins is ferromagnetic. These traits of BMS and BMM in Ni[TCNE] networks add additional features to the family of 2D bipolar magnetic materials. This study paves the way for the design of organic based 2D bipolar magnetic spintronics materials.
Analysis of Ion‐Diffusion‐Induced Interface Degradation in Inverted Perovskite Solar Cells via Restoration of the Ag Electrode
Authors: Lee Hyunho , Lee Changhee
Published: December 2017

Straightforward evidence for ion‐diffusion‐induced interfacial degradation in inverted perovskite solar cells is presented. Over 1000 h, solar cells inevitably undergo degradation, especially with respect to the current density and fill factor. The Ag electrode is peeled off and re‐evaporated to investigate the effect of the Ag/[6,6]‐phenyl C71 butyric acid methyl ester (PCBM) interfacial degradation on the photovoltaic performance at days 10 (240 h), 20 (480 h), 30 (720 h), and 40 (960 h). The power conversion efficiency increases after the Ag electrode restoration process. While the current density shows a slightly decreased value, the fill factor and open‐circuit voltage increase for the new electrode devices. The decrease in the activation energy due to the restored Ag electrode induces recovery of the fill factor. The diffused I− ions react with the PCBM molecules, resulting in a quasi n‐doping effect of PCBM. Upon electrode exchange, the reversible interaction between the iodine ions and PCBM causes current density variation. The disorder model for the open‐circuit voltage over a wide range of temperatures explains the open‐circuit voltage increase at every electrode exchange. Finally, the degradation mechanism of the inverted perovskite solar cell over 1000 h is described under the proposed recombination system.
1,6‐Conjugate Addition of 1,3‐Dicarbonyl Compounds to para‐Quinone Methides Enabled by Noncovalent N‐Heterocyclic Carbene Catalysis
Authors: Santra Surojit , Porey Arka , Guin Joyram
Published: December 2017

Catalysis with N‐heterocyclic carbenes (NHCs) via substrate activation through noncovalent interactions offers a great opportunity to perform organic transformations. Herein, we demonstrate an efficient catalytic method for the 1,6‐conjugate addition of 1,3‐dicarbonyl compounds to para‐quinone methides (p‐QMs) using NHCs as Brønsted‐base catalysts. The method is applicable to a wide range of functionalized substrates with respect to both 1,3‐diketones and p‐QMs. An initial study using chiral NHCs provides information on the feasibility of developing a catalytic enantioselective variant of this reaction.
Reinforcement of polysiloxane/silica elastomer composite by introduction of sacrificial bonds
Authors: Zhao Dannan , Chen Guowen , Yao Huiling , Song Yuanchao
Published: December 2017

It is a challenge to improve tear strength of silicone rubber, especially at high filler loading circumstances. A method is offered here to introduce sacrificial bonds into the system. In particular, amide group was introduced onto the phenyl group of monomer methyl phenyl cyclosiloxane (
first, and this functionalized monomer (
was further used for copolymerization with octamethylcyclotetrasiloxane (D4) and 2,4,6,8‐tetravinyl‐2,4,6,8‐tetramethyl‐cyclotetrasiloxane (
). Vulcanizates composed by this new copolymer (1A‐50) which amide group‐containing is 1 wt % and with 50 phr TS‐530 exhibit high tear strength of about 54 N • mm−1, which is three times higher than that composed by polydimethylsiloxane (PDMS)/TS‐530 (50 phr). The mechanical test indicates this new copolymer a promising candidate for the construction of high tear resistant silicone rubber, especially at high filler loading circumstances. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46129.
Long‐Term Effects of Neonatal Hyperoxia in Adult Mice
Authors: Kumar Vasantha H.S. , Wang Huamei , Kishkurno Sergei , Paturi Babu S , Nielsen Lori , Ryan Rita M.
Published: December 2017

The outcomes of premature infants have improved greatly; however, the health risks in adulthood are still relatively unclear. Bronchopulmonary dysplasia (BPD) in premature infants is a major risk factor for alteration in lung function and predisposition to respiratory morbidity, and is associated with hyperoxia. The study explores the effect of neonatal hyperoxia on organ systems in adult mice. Newborn mouse litters were randomized to 85%O2 or room air (RA) on P3 for 12 days; mice were sacrificed at P3, P7, P15, 3 months and 9 months. Lungs were assessed by histopathology, radial alveolar count, mean linear intercept, and α‐Smooth muscle actin immunohistochemistry. Aortic assessment included histology, wall thickness, elastin, and collagen content. Glomerular histology and nephron number were assessed in the kidneys. Hyperoxia‐exposed mice had progressive alveolar simplification and poor weight gain over time. Greater thickness of pulmonary arterioles by 3 months and a higher Fulton index by 9 months suggest worsening pulmonary hypertension. Aortic wall thickness to lumen ratio was greater with a lower aortic elastin‐to‐collagen ratio suggesting long‐term effects of neonatal hyperoxia. Hyperoxia‐exposed mice at 9 months had smaller glomeruli as indicated by glomerular diameter and volume. Prolonged neonatal hyperoxia during the critical period of development induces irreversible lung damage, pulmonary hypertension and structural changes in the kidneys and aorta in adult mice. This could have implications for chronic adult diseases following exposure to high levels of oxygen in the newborn period. Anat Rec, 301:717–726, 2018. © 2017 Wiley Periodicals, Inc.
Subchondral Bone Radiodensity Patterns in the Glenoid Fossa of Ape and Human Scapulae
Authors: Patel Biren A. , Romanu Joshua T. , Carlson Kristian J.
Published: December 2017

Regions of denser subchondral bone deep to a joint's articular surface indicate locations where the joint experiences relatively higher or more frequent compressive trans‐articular forces than less dense regions. Human clinically focused studies have hypothesized that regional variation of acquired with computed tomography osteoabsorptiomety (CT‐OAM), in the scapular glenoid fossa (GF) is specifically related to forces arising from everyday rotator cuff muscle function. We test this hypothesis by investigating the relationship between rotator cuff function and GF HiRD subchondral bone patterns in a broader comparative context. CT‐OAM was used on scapulae of chimpanzees, gibbons and humans to visualize HiRD subchondral bone patterns and assess regional (anterior–posterior; superior–inferior) differences in HiRD concentrations within each group. Like patterns observed in humans, ape GFs show HiRD concentrations in anterior, posterior and superior regions. Gibbons exhibit significantly larger concentrations anteriorly, probably serving as a skeletal correlate of increased subscapularis activity during humeral internal rotation during arm‐swinging locomotion. Chimpanzees exhibit relatively larger areas posteriorly (though not statistically significant), conceivably serving as a correlate of increased infraspinatus activity during humeral external rotation and retraction during knuckle‐walking. All groups show relatively larger HiRD areas superiorly, likely correlating with forceful humeral abduction (rather than adduction) during routine upper limb use across behaviors. Subchondral bone HiRD patterns in the GF appear to correspond with normal and unbalanced rotator cuff activity and force production not only in humans, but also in other primates, thereby corroborating their value in human clinical studies and functional morphology research. Anat Rec, 301:776–785, 2018. © 2017 Wiley Periodicals, Inc.
Photooxidation of a Twisted Isoquinolinone
Authors: Li Gang , Zhao Jianfeng , Yang Shufan , Li Yongxin , Rakesh Ganguly , Zhang Qichun
Published: December 2017

Understanding the oxidation mechanism and positions of twistacenes and twistheteroacenes under ambient conditions is very important because such knowledge can guide us to design and synthesize novel, larger stable analogues. Herein, we demonstrated for the first time that a twisted isoquinolinone can decompose under oxygen and light at room temperature. The as‐decomposed product 1 was fully characterized through conventional methods as well as single‐crystal structure analysis. Moreover, the physical properties of the as‐obtained product were carefully investigated and the possible formation mechanism was proposed.
Detection of radial velocity variability of HD 16673 with TIGRE
Authors: Mittag M. , Hempelmann A. , Fuhrmeister B. , Czesla S. , Schmitt J. H. M. M.
Published: December 2017

During our TIGRE activity monitoring of late‐type stars, large radial velocity (RV) variations in the F‐type star HD 16673 were noticed. An automatic pipeline procedure using data in the wavelength range from 6000 to 7900 Å was developed and telluric lines are used as reference to determine accurate radial velocities. The RV curve demonstrates the binary nature of the HD 16673 system and allows the determination of the orbital parameters of the system. Based on the derived mass function, we obtain inclination‐dependent mass estimates for the secondary component, which orbits with a period of 37.09 days in a slightly eccentric orbit and is probably a late‐type star.
When MicroRNAs Meet RNA Editing in Cancer: A Nucleotide Change Can Make a Difference
Authors: Wang Yumeng , Liang Han
Published: December 2017

RNA editing is a major post‐transcriptional mechanism that changes specific nucleotides at the RNA level. The most common RNA editing type in humans is adenosine (A) to inosine (I) editing, which is mediated by ADAR enzymes. RNA editing events can not only change amino acids in proteins, but also affect the functions of non‐coding RNAs such as miRNAs. Recent studies have characterized thousands of miRNA RNA editing events across different cancer types. Importantly, individual cases of miRNA editing have been reported to play a role in cancer development. In this review, we summarize the current knowledge of miRNA editing in cancer, and discuss the mechanisms on how miRNA‐related editing events modulate the initiation and progression of human cancer. Finally, we discuss the challenges and future directions of studying miRNA editing in cancer.
Methanol independent induction in Pichia pastoris by simple derepressed overexpression of single transcription factors
Authors: Vogl Thomas , Sturmberger Lukas , Fauland Pia C. , Hyden Patrick , Fischer Jasmin E. , Schmid Christian , Thallinger Gerhard G. , Geier Martina , Glieder Anton
Published: December 2017

Carbon source regulated promoters are well‐studied standard tools for controlling gene expression. Acquiring control over the natural regulation of promoters is important for metabolic engineering and synthetic biology applications. In the commonly used protein production host Komagataella phaffii (Pichia pastoris), methanol‐inducible promoters are used because of their tight regulation and exceptional strength. Yet, induction with toxic and flammable methanol can be a considerable safety risk and cannot be applied in many existing fermentation plants. Here we studied new regulatory circuits based on the most frequently used alcohol oxidase 1 promoter (PAOX1), which is tightly repressed in presence of repressing carbon sources and strongly induced by methanol. We compared different overexpression strategies for putative carbon source dependent regulators identified by a homology search in related yeasts and previously published literature in order to convert existing methanol dependent expression strains into methanol free systems. While constitutive overexpression showed only marginal or detrimental effects, derepressed expression (activated when the repressing carbon source is depleted) showed that three transcription factors (TFs) are single handedly suitable to strongly activate PAOX1 in P. pastoris without relying on any specifically engineered host strains. Transcriptome analyses demonstrated that Mxr1, Mit1, and Prm1 regulate partly overlapping and unique sets of genes. Derepressed overexpression of a single TF was sufficient to retrofit existing PAOX1 based expression strains into glucose/glycerol regulated, methanol‐free systems. Given the wide applicability of carbon source regulated promoters, the simplicity and low cost of controlling carbon source feed rates in large scale bioreactors, similar approaches as in P. pastoris may also be useful in other organisms.
Identification of process conditions influencing protein aggregation in Chinese hamster ovary cell culture
Authors: Paul Albert J. , Handrick René , Ebert Sybille , Hesse Friedemann
Published: December 2017

Protein aggregation of monoclonal antibodies (mAbs) is a common phenomenon associated with the production of these biopharmaceuticals. These aggregates can lead to adverse side effects in patients upon administration, thus expensive downstream processing steps to remove the higher molecular weight species are inevitable. A preferable approach is to reduce the level of aggregation during bioprocessing by a careful adjustment of critical process parameters. Recently, new analytical methods enabled characterization of mAb aggregation during bioprocessing of mammalian cells. Furthermore, rapid and efficient bioprocess optimization has been performed using design of experiments (DoE) strategies. In this work, we describe a DoE‐based approach for the analysis of process parameters and cell culture additives influencing protein aggregation in Chinese hamster ovary (CHO) cell cultures. Important bioprocess variables influencing the aggregation of mAb and host cell proteins were identified in initial screening experiments. Response surface modeling was further applied in order to find optimal conditions for the reduction of protein aggregation during cell culture. It turned out that a temperature‐shift to 31 °C, osmolality above 420 mOsm/kg, agitation at 100 rpm and 0.04% (w/v) antifoam significantly reduced the level of aggregates without substantial detrimental effects on cell culture performance in our model system. Finally, the aggregation reducing conditions were verified and applied to another production system using a different bioprocess medium and another CHO cell line producing another mAb. Our results show that protein aggregation can be controlled during cell culture and helps to improve bioprocessing of mAbs, by giving insights into the protein aggregation at its origin in mammalian cell culture.
Change in symptomatic burden and life satisfaction during short‐term psychotherapy: Focusing on the role of family income
Authors: Behn Alex J. , Errázuriz Paula A. , Cottin Marianne , Fischer Candice
Published: December 2017

Objective

The article examines the role of family income on the relationship between change in symptomatic burden and change in life satisfaction during six sessions of naturalistically delivered individual psychotherapy.

Method

Five hundred and thirty‐two clients receiving psychotherapy were assessed at baseline and on a session‐to‐session basis with the OQ‐30.2 and with a life satisfaction questionnaire. Data were analysed using a bivariate latent class model with structured residuals that included cross‐lagged and autoregressive components between residual scores at each time point. Adjusted family income and a binary low versus high‐income group variable were added as exogenous baseline covariates at different stages of the analyses.

Results

Regardless of income level, clients show improvement in psychological distress and life satisfaction as a function of time during treatment. Initial levels and improvement in life satisfaction are related to initial levels and improvement in psychological distress, and lower family income is related to slower decreases in psychological distress. When the whole sample is analysed, psychological distress and life satisfaction show reciprocal prospective relationships at the within‐person level. When models are estimated by income group, casual relationships at the within‐person level vary as a function of income.

Conclusion

Family income level appears to play a significant role in the relationship between symptom improvement and life satisfaction during psychotherapy.
Screening for mental health needs of New Zealand youth in secure care facilities using the MAYSI‐2
Authors: McArdle Sean , Lambie Ian
Published: December 2017

Background

Young people admitted to secure facilities generally have particularly high rates of mental, emotional and behavioural problems, but little is known about the mental health needs of this group in New Zealand.

Aims

To describe prevalence of probable mental health disorder and related needs among young people in secure facilities in New Zealand.

Methods

Massachusetts youth screening instrument – second version (MAYSI‐2) data were obtained from the records of young people admitted to one secure care facility (n = 204) within a 12 month period. We used descriptive statistics to determine prevalence of problems overall and multivariate analysis of variance to compare MAYSI‐2 scores between gender and ethnic groups.

Results

Nearly 80% of these young people scored above the ‘caution’ or ‘warning’ cut‐off on the MAYSI‐2, a substantially higher proportion than reported in studies in other countries. There was a tendency for girls and for Maori and Pacific Islander subgroups to have a higher rate of probable psychopathology.

Conclusions

Young people in secure facilities in New Zealand have substantial service needs. Early intervention that engages them in services upon first contact with the youth justice system might help reduce this burden. Further validation of the MAYSI‐2 in New Zealand may be warranted because of the unique ethnic make‐up of these young offenders. Copyright © 2017 John Wiley & Sons, Ltd.
Predictors of patient radiation exposure during transcatheter aortic valve replacement
Authors: Goldsweig Andrew M. , Kennedy Kevin F. , Kolte Dhaval , Abbott J. Dawn , Gordon Paul C. , Sharaf Barry L. , Sellke Frank W. , Ehsan Afshin , Sodha Neel R. , Rutar Frank , Aronow Herbert D.
Published: December 2017

Background

Transcatheter aortic valve replacement (TAVR) exposes patients to radiation.

Objectives

We sought to identify factors associated with higher radiation exposure and to quantify their relative influence, which may inform reduction of this hazard.

Methods

All TAVR procedures at Rhode Island Hospital between March 20, 2012 and February 12, 2017 were included. Procedures were performed by two co‐primary operators using a Siemens Artis Zeego system. Radiation metrics were generated by the imaging system. The primary metric was dose‐area product (DAP, Gy*cm2), and secondary metrics were reference point air kerma (mGy) and fluoroscopy time (minutes). Data collected for the STS/ACC TVT Registry were utilized to develop a multivariable linear regression model predicting DAP.

Results

In 294 TAVRs, median DAP was 169 Gy*cm2 [interquartile range (IQR) 106–238]. The r2 values for the full 27‐variable DAP model and reduced eight‐variable model were 0.457 and 0.420, respectively. Valve area, aortic insufficiency, and procedure year (suggesting absence of a learning curve) were non‐significant predictors in the full model, while increasing weight, cutdown transfemoral access, higher pre‐procedure creatinine and hemoglobin, and vascular complications predicted higher DAP in both models. Results were unchanged when DAP was log‐transformed. Secondary models for air kerma and fluoroscopy time revealed similar predictors.

Conclusion

Factors associated with increased procedural complexity and duration as well as radiation attenuation and scatter predict increased patient radiation exposure during TAVR. Modification of procedural technique, especially using percutaneous femoral vascular access, may facilitate reduction in exposure.
ANALYSIS OF THE VERTICAL SHEAR DESIGN MODEL FOR STEEL‐CONCRETE COMPOSITE SLABS
Authors: Pereira Miguel , Simões Rui , Duarte João
Published: December 2017

Usually, the design of composite slabs with short spans, or with current spans with the longitudinal shear behaviour improved by reinforcing systems, is governed by the vertical shear resistance. Nevertheless, the vertical shear resistance of composite slabs, according with european standard EN 1994‐1‐1, is calculated in the same way as reinforcing concrete slabs, being the contribution of the steel sheet not taken into account adequately. In this paper, a reflection and a comparison between vertical shear design models according different standards or methodologies are presented. It is also presented the results of a short experimental programme, composed by 2 experimental tests in composite slabs with short spans, carried out in the Department of Civil Engineering of University of Coimbra.
COMPARISON OF DESIGN FOR COMPOSITE BEAMS IN STEEL AND CONCRETE ACCORDING TO EUROCODE 4 AND CHINESE DESIGN CODES
Authors: Zhang Qingjie , Schäfer Markus
Published: December 2017

In this article, the design of composite beams in steel and concrete based on EN1994‐1‐1 and Chinese JGJ138‐2016 is compared. In general, design according to Eurocode 4 is more detailed. Differences of effective width between both codes are explained in theory and through parameter studies. Allowance for moment redistribution is also compared. For bending moment resistance, the comparison is carried out with a parameter study on single span beams. For longitudinal shear design, the resistance of shear studs, minimum shear connection degree, the arrangement of shear studs, longitudinal shear resistance in concrete slabs based on both codes are compared.
EFFECT OF AN INTERFACE DEFECT IN A PATCH/LAYER JOINT UNDER DYNAMIC TIME HARMONIC LOAD
Authors: Kirilova Elisaveta G. , Becker Wilfried , Ivanova Jordanka A. , Petrova Tatyana S.
Published: December 2017

The study deals with the response of a smart patch/layer joint with interface defect (gap) subjected to dynamic time harmonic mechanical and electric load at environmental conditions. In order to find the axial displacements, shear stress and interface debond length in a closed analytical form a 1D modified, shear lag analysis is used. At given joint geometry and three different positions of the gap, a genetic algorithm is implemented to find the values of the model parameters at which a vanishing/minimal debond length is ensured. Moreover, for each optimal solution the influence of the length of the gap as well as the model parameters on the length of the interface debond length is investigated.
EXPERIMENTAL ANALYSIS OF UNSTIFFENED CYLINDRICALLY CURVED PANELS
Authors: Ljubinkovic Filip , Martins João Pedro , Gérvasio Helena , da Silva Luís Simões , Leitao Carlos
Published: December 2017

The main goal of this research is to characterize the structural behavior of panels as the individual members under compressive stresses. Two unstiffened curved panels subjected to pure compression are experimentally and numerically examined. The thickness of the panels is constant and equal to 4 mm, whereas the radius is equal to 20 m. The results will be used to calibrate numerical models, which will be further used for the parametric study. One of the main goals of the study is a use of Digital Image Correlation System (ARAMIS) to measure full‐field 3D deformations, strains and stresses of the panel during the load application.
EXPERIMENTAL AND NUMERICAL DYNAMIC ANALYSIS OF STEEL‐CONCRETE COMPOSITE FOOTBRIDGES SUBJECTED TO PEDESTRIANS WALKING
Authors: da Silva Irwing Aguiar Ribeiro , da Silva José Guilherme Santos
Published: December 2017

This research work aims the evaluation of the dynamic structural response of steel‐concrete composite footbridges, based on the experimental tests and numerical modelling. The investigated structural system is related to a real and existing steel‐concrete pedestrian footbridge, which presents two spans of 29.5m and 24m, respectively, and a total extension of 53.5m. The structural model is located at the Osvaldo Aranha Street, next of the new Maracanã Stadium, at the city of Rio de Janeiro/RJ, Brazil. Based on the developed analysis methodology, the dynamic structural response of the investigated footbridge is compared to the limits proposed by design standards and recommendations, aiming to evaluate the performance of the structure when the human comfort is considered.
INFLUENCE OF THE DEGREE OF SHEAR CONNECTION ON THE LOAD CARRYING CAPACITY OF A COMPOSITE BEAM IN FIRE
Authors: Pfenning Samuel , Tresch Jürgen , Pennisi Luca , Brunkhorst Sven , Mensinger Martin
Published: December 2017

This paper discusses the influence of elevated temperatures on the partial connection theory of composite beams with headed stud shear connectors. The load carrying behaviour of headed stud shear connectors in fire situation and its influence on the degree of shear connection of the composite beam is elaborated. Furthermore, the influence of the degree of shear connection on the load carrying behaviour of a single span composite beam is shown. Results suggest, that the degree of shear connection has only influence on the load carrying capacity of composite beams at ambient temperature, at elevated temperatures the softening of the steel section due to the rising temperature is the predominant factor.
NEXT GENERATION OF EUROCODE 3 – EVOLUTION BY IMPROVEMENTS AND HARMONIZATION
Authors: Kuhlmann Ulrike , Schmidt‐Rasche Christina
Published: December 2017

This paper gives an overview on recent work regarding the revision of EN 1993 on European level including selected scientific and technical issues and a summary of the activities executed within the European Standardization committee CEN/TC250/SC3 “Design of Steel Structures” under the chair of Prof. Dr.‐Ing. Ulrike Kuhlmann. This includes the description of current normative developments for the 2nd generation of Eurocodes which aim at an evolution by improvements and harmonization of the existing codes. More specific tasks are described to be realized by Project Teams in the frame of the so‐called Mandate M/515 to further develop all Eurocodes. In addition, a technical review of selected rules is given on a number of issues, which support the code revision and reflect well the recent tendencies in steel structures.
ROBUSTNESS, REDUNDANCY AND PROGRESSIVE COLLAPSE OF FIXED OFFSHORE STRUCTURES
Authors: Refachinho Miguel , Rigueiro Constança , Martins João Pedro , Matos Rui
Published: December 2017

The purpose of this paper is to present an evaluation of the robustness of fixed offshore structures, through the understanding of, i) major historical accidents, and its repercussions in the codes and regulations, ii) review the methods used to assure robustness, with special focus in offshore standards, but also with civil Eurocodes; iii) Robustness assessment and measurement and, iv) which factors and mechanical properties of structures influences robustness. To be able to measure the Robustness of a structure under accidental or unforeseen events it is necessary to quantify its ultimate capacity and establish its post collapse behaviour. Therefore, a case study consisting of Non‐Linear analysis (pushover) of a four‐legged jacket is developed using USFOS software, where several structural properties are made variable and the effect in the robustness is measured.
SEISMIC RESPONSE OF STEEL MOMENT FRAMES WITH SEMI‐CONTINUOUS JOINTS
Authors: SATO Atsushi , WALD František
Published: December 2017

Load action due to seismic is computed based on design spectrum, where it is determined by elastic response spectrum and behaviour factor. The difference of cyclic behaviour of the dissipative zones may influence the energy absorption capacity; semi‐continuous joints that are allowed to use in steel moment frames may affect the response of the structure under seismic event. However, Ch.6 in EN 1998–1:2004 does not have any specific rules that can evaluate the semi‐continuous joints effects. Time‐history analysis under 44 ground motions was conducted, and the effect of semi‐continuous joints to the maximum storey drift ratio was evaluated. Finally, sample result that can evaluate the joint effect was shown.
SIMPLE FIRE DESIGN OF COLD‐FORMED STEEL C‐SECTION BEAMS WITH LATERAL–TORSIONAL BUCKLING
Authors: Laím Luís , Rodrigues João Paulo C.
Published: December 2017

Fire design rules for cold‐formed steel beams are commonly based on past research on hot‐rolled steel beams. Hence this paper present a methodology for calculating the fire response of unrestrained cold‐formed steel C‐section flexural members, based on guidelines of EN1993‐1.2 for fire design of steel beams and on results of experimental and numerical studies. European fire design rules were found to be unsafe or over‐conservative, depending on their relative slenderness and serviceability load applied on the beams. Therefore, new formulae for lateral–torsional buckling of unrestrained cold‐formed steel C‐section flexural members, which approximate better their real behaviour in case of fire, are proposed. Comparison with numerical moment capacities demonstrates the accuracy of the new design methodology.
Suifficent choice of material to avoid brittle fractures of foundation components of offshore wind power plants made of steel in accordance with EC3 part 1‐10
Authors: Kühn Bertram , Krieglstein Tim
Published: December 2017

The choice of material for steel constructions in maritime environments, e.g. wind power plants, is not included in EC3 yet. On the other hand rules for a suifficent choice of material for structures in maritime environments do not exist. Till now, no physically based design method for the choice of steel grade in such environments exist. But a suitable and demand oriented choice of steel grade is very important for an economic design. A failure due to brittle fracture is avoided by a suitable choice of steel grade or rather by limitation of the maximum plate thickness. A physically based design method is given in EC3 part 1–10. Here table 2.1 shows the values of the maximum plate thickness in dependence of the steel grade and reference temperature. All data in table 2.1 were determined on the basis of assumptions with a clear focus on bridge constructions. Therefore, it is doubtful if table 2.1 can also be used for offshore wind power plants. For example crack growth parameters (constants in Paris‐law) have an influence on the brittle fracture design which are different for regular conditions of bridges in comparison to maritime environments. A research project was carried out at the University of applied sciences Mittelhessen (THM). As a first step it was investigated which individual boundary conditions differ between bridge construction and foundations in maritime environments. In the second step tabulated values of the maximum plate thickness with the adapted boundary conditions were determined based on the same calculation algorithm as EC3 part 1‐10. Finally a recommendation for the practice‐oriented use of Table 2.1 was developed for foundation components of offshore wind power plants.