bluuebunny/crossref_metadata_2025 huggingface dataset:
“Three‐in‐One:” A New 3D Hybrid Structure of Li3V2(PO4)3 @ Biomorphic Carbon for High‐Rate and Low‐Temperature Lithium Ion Batteries
Authors: Cheng Yi , Feng Kai , Wang Huaiqing , Zhang Hongzhang , Li Xianfeng , Zhang Huamin
Published: September 2017

Li3V2(PO4)3 with high specific capacity and high operating potential has been considered as a promising cathode for the next generation lithium ion batteries (LIBs). But the low electronic conductivity restricts its practical applications. Here, a rational design of 3D hybrid structures of Li3V2(PO4)3 @ biomorphic carbon is presented. The 3D hybrid structures built from 0D, 1D, and 2D composites are carbonized from biomorphic carbon, namely, “three‐in‐one.” The synergistic effects of the carbon with different dimensions provide high electronic conductivity and good structural stability. In addition, abundant porous channels in the structure accelerate transfer of the Li+. This unique cathode material reaches the capacity retention up to 96% (relative to 1 C) when the rate increased to 50 C. When combines with Li4Ti5O12 to form a full battery, it delivers a capacity of 174 mAh g−1 at room temperature and retains 150 mAh g−1 when the temperature decreases to −40 °C. The excellent properties are attributed to the high electronic conductivity, fast ion transport channels, large electrode–electrolyte contact area, and robust structure stability of the 3D hybrid architecture. This work provides a new strategy for constructing 3D framework electrode materials for LIBs.
Ultrahigh Electrocatalytic Conversion of Methane at Room Temperature
Authors: Ma Ming , Jin Bing Jun , Li Ping , Jung Myung Sun , Kim Jin Il , Cho Yoonjun , Kim Sungsoon , Moon Jun Hyuk , Park Jong Hyeok
Published: September 2017

Due to the greenhouse effect, enormous efforts are done for carbon dioxide reduction. By contrast, more attention should be paid for the methane oxidation and conversion, which can help the effective utilization of methane without emission. However, methane conversion and utilization under ambient conditions remains a challenge. Here, this study designs a Co3O4/ZrO2 nanocomposite for the electrochemical oxidation of methane gas using a carbonate electrolyte at room temperature. Co3O4 activated the highly efficient oxidation of methane under mild electric energy with the help of carbonate as an oxidant, which is delivered by ZrO2. Based on the experimental results, acetaldehyde is the key intermediate product. Subsequent nucleophilic addition and free radical addition reactions accounted for the generation of 2‐propanol and 1‐propanol, respectively. Surprisingly, this work achieves a production efficiency of over 60% in the conversion of methane to produce these long‐term stable products. The as‐proposed regional electrochemical methane oxidation provides a new pathway for the synthesis of higher alcohols with high production efficiencies under ambient conditions.
Highly Durable Platinum Single‐Atom Alloy Catalyst for Electrochemical Reactions
Authors: Kim Jiwhan , Roh Chi‐Woo , Sahoo Suman Kalyan , Yang Sungeun , Bae Junemin , Han Jeong Woo , Lee Hyunjoo
Published: September 2017

Single atomic Pt catalyst can offer efficient utilization of the expensive platinum and provide unique selectivity because it lacks ensemble sites. However, designing such a catalyst with high Pt loading and good durability is very challenging. Here, single atomic Pt catalyst supported on antimony‐doped tin oxide (Pt1/ATO) is synthesized by conventional incipient wetness impregnation, with up to 8 wt% Pt. The single atomic Pt structure is confirmed by high‐angle annular dark field scanning tunneling electron microscopy images and extended X‐ray absorption fine structure analysis results. Density functional theory calculations show that replacing Sb sites with Pt atoms in the bulk phase or at the surface of SbSn or ATO is energetically favorable. The Pt1/ATO shows superior activity and durability for formic acid oxidation reaction, compared to a commercial Pt/C catalyst. The single atomic Pt structure is retained even after a harsh durability test, which is performed by repeating cyclic voltammetry in the range of 0.05–1.4 V for 1800 cycles. A full cell is fabricated for direct formic acid fuel cell using the Pt1/ATO as an anode catalyst, and an order of magnitude higher cell power is obtained compared to the Pt/C.
Strukturierte kolloidale photonische Kristalle
Authors: Hou Jue , Li Mingzhu , Song Yanlin
Published: September 2017

Kolloidale photonische Kristalle (PCs) sind einfach herzustellen, kostengünstig und vielfältig im Hinblick auf Modifizierung und Funktionalisierung. Strukturierte kolloidale PCs bieten einen neuen Ansatz für die Entwicklung von leistungsstarken PC‐Vorrichtungen mit besonderen Strukturen und spezifischen Funktionen. In diesem Kurzaufsatz wird ein Überblick über die Methoden zur Herstellung von strukturierten kolloidalen PCs gegeben – Anordnung mithilfe von strukturierten Substraten, Tintenstrahldruck sowie selektive Immobilisierung und Modifizierung. Außerdem werden die Vorteile von Vorrichtungen mit strukturierten PCs im Einzelnen behandelt, beispielsweise für die Sensorik, mikrofluidische Kanäle, Nachweisverfahren, Displays und als Elemente zur Fälschungssicherung.
Anion–π Catalysis of Diels–Alder Reactions
Authors: Liu Le , Cotelle Yoann , Bornhof Anna‐Bea , Besnard Céline , Sakai Naomi , Matile Stefan
Published: September 2017

Among concerted cycloadditions, the Diels–Alder reaction is the grand old classic, which is usually achieved with acid catalysis. In this report, hydroxypyrones, oxa‐, and thiazolones are explored because they provide access to anionic dienes. Their [4+2] cycloaddition with cyclic and acyclic dienophiles, such as maleimides and fumarates, affords bicyclic products with four new stereogenic centers. Bifunctional anion–π catalysts composed of amine bases next to the π surface of naphthalenediimides (NDIs) are shown to selectively stabilize the “open”, fully accessible anionic exo transition state on the π‐acidic aromatic surface. Our results also include reactivities that are hard to access with conventional organocatalysts, such as the exo‐specific and highly enantioselective Diels–Alder reaction of thiazolones and maleimides with complete suppression of the otherwise dominant Michael addition. With increasing π acidity of the anion–π catalysts, the rates, chemo‐, diastereo‐, and enantioselectivities increase consistently.
Direct Observation of Hemithioindigo‐Motor Unidirectionality
Authors: Huber Ludwig Alexander , Hoffmann Kerstin , Thumser Stefan , Böcher Niklas , Mayer Peter , Dube Henry
Published: September 2017

Hemithioindigo molecular motors undergo very fast unidirectional rotation upon irradiation with visible light, which has prevented a complete analysis of their working mechanism. In this work, we have considerably slowed down their motion by using a new synthesis for sterically hindered motor derivatives. This method allowed the first observation of all four intermediate states populated during rotation. The exact order in which each isomeric state is formed under irradiation conditions was elucidated using low temperature 1H NMR spectroscopy in conjunction with other analytical methods. At the same time, complete unidirectionality could also be directly shown. Access to slowly rotating hemithioindigo motors opens up a plethora of new applications for visible‐light‐induced unidirectional motions, especially in areas such as catalysis, smart materials, and supramolecular chemistry.
Evidence of Organic Luminescent Centers in Sol–Gel‐Synthesized Yttrium Aluminum Borate Matrix Leading to Bright Visible Emission
Authors: Burner Pauline , Sontakke Atul D. , Salaün Mathieu , Bardet Michel , Mouesca Jean‐Marie , Gambarelli Serge , Barra Anne‐Laure , Ferrier Alban , Viana Bruno , Ibanez Alain , Maurel Vincent , Gautier‐Luneau Isabelle
Published: September 2017

Yttrium aluminum borate (YAB) powders prepared by sol–gel process have been investigated to understand their photoluminescence (PL) mechanism. The amorphous YAB powders exhibit bright visible PL from blue emission for powders calcined at 450 °C to broad white PL for higher calcination temperature. Thanks to 13C labelling, NMR and EPR studies show that propionic acid initially used to solubilize the yttrium nitrate is decomposed into aromatic molecules confined within the inorganic matrix. DTA‐TG‐MS analyses show around 2 wt % of carbogenic species. The PL broadening corresponds to the apparition of a new band at 550 nm, associated with the formation of aromatic species. Furthermore, pulsed ENDOR spectroscopy combined with DFT calculations enables us to ascribe EPR spectra to free radicals derived from small (2 to 3 rings) polycyclic aromatic hydrocarbons (PAH). PAH molecules are thus at the origin of the PL as corroborated by slow afterglow decay and thermoluminescence experiments.
Electron‐Transfer and Hydride‐Transfer Pathways in the Stoltz–Grubbs Reducing System (KOtBu/Et3SiH)
Authors: Smith Andrew J. , Young Allan , Rohrbach Simon , O'Connor Erin F. , Allison Mark , Wang Hong‐Shuang , Poole Darren L. , Tuttle Tell , Murphy John A.
Published: September 2017

Recent studies by Stoltz, Grubbs et al. have shown that triethylsilane and potassium tert‐butoxide react to form a highly attractive and versatile system that shows (reversible) silylation of arenes and heteroarenes as well as reductive cleavage of C−O bonds in aryl ethers and C−S bonds in aryl thioethers. Their extensive mechanistic studies indicate a complex network of reactions with a number of possible intermediates and mechanisms, but their reactions likely feature silyl radicals undergoing addition reactions and SH2 reactions. This paper focuses on the same system, but through computational and experimental studies, reports complementary facets of its chemistry based on a) single‐electron transfer (SET), and b) hydride delivery reactions to arenes.
Cancer‐Targeted Selenium Nanoparticles Sensitize Cancer Cells to Continuous γ Radiation to Achieve Synergetic Chemo‐Radiotherapy
Authors: Chan Leung , He Lizhen , Zhou Binwei , Guan Shouhai , Bo Mingjun , Yang Yahui , Liu Ying , Liu Xiao , Zhang Yanyang , Xie Qiang , Chen Tianfeng
Published: September 2017

Cancer radiotherapy with 125I seeds demonstrates higher long‐term efficacy and fewer side effects than traditional X‐ray radiotherapy owing to its low‐dose and continuous radiation but is still limited by radioresistance in clinical applications. Therefore, the design and synthesis of sensitizers that could enhance the sensitivity of cancer cells to 125I seeds is of great importance for future radiotherapy. Selenium nanoparticles (SeNPs) have been found to exhibit high potential in cancer chemotherapy and as drug carriers. In this study, we found that, based on the Auger‐electron effect and Compton effect of Se atoms, cancer‐targeted SeNPs in combination with 125I seeds achieve synergetic effects to inhibit cancer‐cell growth and colony formation through the induction of cell apoptosis and cell cycle arrest. Detailed studies on the action mechanisms reveal that the combined treatments effectively activate intracellular reactive oxygen species (ROS) overproduction to regulate p53‐mediated DNA damage apoptotic signaling pathways and mitogen‐activated protein kinase (MAPK) phosphorylation and to prevent the self‐repair of cancer cells simultaneously. Taken together, the combination of SeNPs with 125I seeds could be further exploited as a safe and effective strategy for next‐generation cancer chemo‐radiotherapy in clinical applications.
Stringent limits on the masses of the supermassive black holes in seven nearby galaxies
Authors: Pagotto I. , Corsini E. M. , Dalla Bontà E. , Beifiori A. , Costantin L. , Cuomo V. , Morelli L. , Pizzella A. , Sarzi M.
Published: September 2017

We present new stringent limits on the mass M• of the central supermassive black hole for a sample of seven nearby galaxies. Our M• estimates are based on the dynamic modeling of the central width of the nebular emission lines measured over sub‐arcsecond apertures with the Hubble Space Telescope. The central stellar velocity dispersion, σc, of the sample galaxies is derived from new long‐slit spectra from ground‐based observations and the bulge effective radius is obtained from a two‐dimensional photometric decomposition of the i‐band images from the Sloan Digital Sky Survey. The derived stringent M• limits run parallel and above the M•−σc relation, with no systematic trend depending on the galaxy distance or morphology. This gives further support to previous findings suggesting that the nuclear gravitational potential is remarkably well traced by the width of the nebular lines when the gas is centrally peaked. With our investigation, the number of galaxies with stringent M• limits obtained from the nebular line width increases to 114 and can be used for studying the scaling relations between M• and properties of their host galaxies.
Olive‐derived biomass as a source of energy and chemicals
Authors: Ruiz Encarnación , Romero‐García Juan Miguel , Romero Inmaculada , Manzanares Paloma , Negro María José , Castro Eulogio
Published: September 2017

Olive trees are cultivated in more than 40 countries worldwide over more than 10 million hectares. In addition to olive oil, a large amount of biomass is produced annually. All this biomass must be adequately handled and disposed of. Conventional disposal methods include direct burning or spreading in fields, but this has economical costs and environmental concerns, as well as wasting a source of energy and chemicals. This review summarizes the most recent proposals for the use of biomass derived from olive tree cultivation and olive oil production processes. Biomass produced from pruning, leaves, olive stones and pomace, extracted olive pomace, and olive waste water are considered, and the main options for processing are reviewed according to recent advances in the literature. The biorefinery concept applied to olive‐derived biomass is also presented and representative works are discussed. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Synthetic Modular Antibody Construction by Using the SpyTag/SpyCatcher Protein‐Ligase System
Authors: Alam Md Kausar , Gonzalez Carolina , Hill Wayne , El‐Sayed Ayman , Fonge Humphrey , Barreto Kris , Geyer C. Ronald
Published: September 2017

Efforts to engineer recombinant antibodies for specific diagnostic and therapy applications are time consuming and expensive, as each new recombinant antibody needs to be optimized for expression, stability, bio‐distribution, and pharmacokinetics. We have developed a new way to construct recombinant antibody‐like “devices” by using a bottom‐up approach to build them from well‐behaved discrete recombinant antibody domains or “parts”. Studies on antibody structure and function have identified antibody constant and variable domains with specific functions that can be expressed in isolation. We used the SpyTag/SpyCatcher protein ligase to join these parts together, thereby creating devices with desired properties based on summed properties of parts and in configurations that cannot be obtained by using genetic engineering. This strategy will create optimized recombinant antibody devices at reduced costs and with shortened development times.
Patient preferences prompt a peek at priorities
Authors: Blankenship James C.
Published: September 2017

Key Points

Patients rate the downsides of bare metal stents (higher restenosis rates) as being of similar magnitude to the downsides of drug eluting stents (longer dual anti‐platelet therapy).

Patient preferences regarding choice of bare metal versus drug eluting stents should be elicited before coronary stenting.

This article does not study actual patient preferences for stent type. Future studies should assess how personalized discussions of trade‐offs of stent types affect patient preferences.
CO2 angiography: Colorless, odorless, but definitely not useless!
Authors: Safian Robert D.
Published: September 2017

Key Points

Contemporary approaches to minimize the risk of acute kidney injury from radiographic contrast (AKI‐RC) rely on preferential use of low‐ or non‐ionic contrast; pre‐hydration; and limiting contrast volume.

This study utilized a meta‐analysis of 677 patients to compare the risk of AKI‐RC after CO2 peripheral angiography versus iodinated contrast (4.3% vs. 11.1%, odds ratio [OR] 0.465, P = 0.048). There was no difference in AKI‐RC in patients with CKD.

This study has many limitations. CO2 angiography is an important technique; proper understanding of its strengths and limitations is essential.
N‐Phosphine Oxide‐Substituted Imidazolylidenes (PoxIms): Multifunctional Multipurpose Carbenes
Authors: Hazra Sunit , Hoshimoto Yoichi , Ogoshi Sensuke
Published: September 2017

This article discusses the concept of N‐heterocyclic carbenes (NHCs) equipped with more than one functional moiety, which allows using these NHCs for multiple purposes. A pioneering example for such NHCs is N‐phosphine oxide‐substituted imidazolylidenes (PoxIms), and their synthesis and strategic use are highlighted. The utility of PoxIms by far exceeds the conventional use as multidentate ligands for metal complexes on account of the synergetic functions of the carbene and the N‐phosphine oxide group(s).
Polyhedral Oligomeric Silsesquioxane (POSS) Bearing Glyoxylic Aldehyde as Clickable Platform Towards Multivalent Conjugates
Authors: Kanfar Nasreddine , Mehdi Ahmad , Dumy Pascal , Ulrich Sébastien , Winum Jean‐Yves
Published: September 2017

The straightforward access to octafunctional “cubic” silsesquioxane platform grafter with pendant glyoxylic aldehydes is described. This clickable hybrid platform readily reacts with oxyamine or hydrazide compounds to provide, respectively, oxime and acylhydrazone conjugates, thereby offering a new and effective access from which one can elaborate multivalent systems for the targeting of biomolecules of interest.
Differential projections of the densocellular and intermediate parts of the hyperpallium in the pigeon (Columba livia)
Authors: Atoji Yasuro , Sarkar Sonjoy , Wild J. Martin
Published: September 2017

The visual Wulst in birds shows a four‐layered structure: apical part of the hyperpallium (HA), interstitial part of HA (IHA), intercalated part of hyperpallium (HI), and densocellular part of hyperpallium (HD). HD also connects with the hippocampus and olfactory system. Because HD is subjacent to HI, the two have been treated as one structure in many studies, and the fiber connections of HD have been examined by afferents and efferents originating outside HD. However, to clarify the difference between these two layers, they need to be treated separately. In the present study, the fiber connections of HD and HI were analyzed with tract‐tracing techniques using a combination of injections of cholera toxin subunit B (CTB) for retrograde tracing and biotinylated dextran amine (BDA) for anterograde tracing. When the two tracers were bilaterally injected in HD, a major reciprocal connection was seen with the dorsolateral subdivision (DL) of the hippocampal formation. When CTB and BDA were bilaterally injected in HI, strong reciprocal connections were found between HI and HA. Next, projection neurons in HD and HI were examined by double staining for CTB combined with vesicular glutamate transporter 2 (vGluT2) mRNA in situ hybridization. After CTB was injected in DL or HA, many neurons revealed CTB+/vGluT2+ in HD or HI, respectively. Furthermore, in situ hybridization showed that DL and HA contained neurons expressing various subunits of ionotropic glutamate receptors: AMPA, kainate, and NMDA types. These results suggest that glutamatergic neurons in HD and HI project primarily to DL and HA, respectively.
SybilTrap: A graph‐based semi‐supervised Sybil defense scheme for online social networks
Authors: Al‐Qurishi Muhammad , Rahman Sk Md Mizanur , Alamri Atif , Mostafa Mohamed A. , Al‐Rubaian Majed , Hossain M. Shamim , Gupta B.B.
Published: September 2017

Sybil attacks are increasingly prevalent in online social networks. A malicious user can generate a huge number of fake accounts to produce spam, impersonate other users, commit fraud, and reach many legitimate users. For security reasons, such fake accounts have to be detected and deactivated immediately. Various defense schemes have been proposed to deal with fake accounts. However, most identify fake accounts using only the structure of social graphs, leading to poor performance. In this paper, we propose a new and scalable defense scheme, SybilTrap. SybilTrap uses a semi‐supervised technique that automatically integrates the underlying features of user activities with the social structure into one system. Unlike other machine learning–based approaches, the proposed defense scheme works on unlabeled data, and it is effective in detecting targeted attacks, because it manipulates different levels of features of user profiles. We evaluate SybilTrap on a dataset collected from Twitter. We show that our proposed scheme is able to accurately detect Sybil nodes as well as huge conspiracies among them.
Murine Retrovirally‐Transduced Bone Marrow Engraftment Models of MLL‐Fusion‐Driven Acute Myelogenous Leukemias (AML)
Authors: Stubbs Matthew C. , Krivtsov Andrei V.
Published: September 2017

MLL‐rearranged leukemia represents approximately 5% to 10% of adult acute myelogenous leukemia (AML) and nearly half of all infant/pediatric acute leukemia cases. These leukemias have a poor prognosis, and there are no approved therapeutic options. The rearrangement in the MLL gene leads to aberrant expression of MLL‐fusion proteins. These are transforming in murine bone marrow and, in particular, on stem cells and myeloid progenitors derived from bone marrow or fetal liver. The commonality of the MLL fusions is the in‐frame fusion of 8 to 11 N‐terminal exons of MLL1 (KMT2a) with the C‐terminus of a partner fusion gene. Currently, over 80 different fusion partners are known. The protocols detailed in this unit focus on bone marrow–derived models only, using one particular MLL fusion, MLL‐AF9. These models have proven effective for drug screening to predict clinical response. © 2017 by John Wiley & Sons, Inc.
Endothelial‐to‐mesenchymal transition in cardiovascular diseases: Developmental signaling pathways gone awry
Authors: Sánchez‐Duffhues Gonzalo , García de Vinuesa Amaya , ten Dijke Peter
Published: September 2017

The process named endothelial‐to‐mesenchymal transition (EndMT) was observed for the first time during the development of the chicken embryo several decades ago. Of interest, accumulating evidence suggests that EndMT plays a critical role in the onset and progression of multiple postnatal cardiovascular diseases. EndMT is controlled by a set of developmental signaling pathways, very similar to the process of epithelial‐to‐mesenchymal transition, which determine the activity of several EndMT transcriptional effectors. Once activated, these EndMT effectors regulate the expression of endothelial‐ and mesenchymal‐specific genes, in part by interacting with specific motifs in promoter regions, eventually leading to the down‐regulation of endothelial‐specific features and acquisition of a fibroblast‐like phenotype. Important technical advances in lineage tracing methods combined with experimental mouse models demonstrated the pathophysiological importance of EndMT for human diseases. In this review, we discuss the major signal transduction pathways involved in the activation and regulation of the EndMT program. Furthermore, we will review the latest discoveries on EndMT, focusing on cardiovascular diseases, and in particular on its role in vascular calcification, pulmonary arterial hypertension, and organ fibrosis. Developmental Dynamics 247:492–508, 2018. © 2017 Wiley Periodicals, Inc.
Nitrogen uptake and transfer in a soybean/maize intercropping system in the karst region of southwest China
Authors: Zhang Hao , Zeng Fuping , Zou Zhigang , Zhang Zhenqian , Li Youzhi
Published: September 2017

Nitrogen (N) deficiency occurs in over 80% of karst soil of southwest China, which restricts regional agricultural production. To test whether N fixed by legumes becomes available to nonfixing companion species, N fluxes between soybean and maize under no, partial, and total restriction of root contact were measured on a karst site in southwest China. N content and its transfer between soybean and maize intercrops were explored in a 2‐year plot experiment, with N movement between crops monitored using 15N isotopes. Mesh barrier (30 μm) and no restrictions barrier root separation increased N uptake of maize by 1.28%–3.45% and 3.2%–3.45%, respectively. N uptake by soybean with no restrictions root separation was 1.23 and 1.56 times higher than that by mesh and solid barriers, respectively. In the unrestricted root condition, N transfer from soybean to maize in no restrictions barrier was 2.34–3.02 mg higher than that of mesh barrier. Therefore, it was implied that soybean/maize intercropping could improve N uptake and transfer efficiently in the karst region of southwest China.
Immune mechanisms in heart failure
Authors: Zhang Yingying , Bauersachs Johann , Langer Harald F.
Published: September 2017

Elevated levels of circulating pro‐inflammatory biomarkers in patients with both ischaemic and non‐ischaemic heart failure (HF) correlate with disease severity and prognosis. Experimental studies have shown activation of immune response mechanisms in the heart to provoke cardiac adverse remodelling and cause left ventricular dysfunction. Consequently, most of the clinical trials targeting elements of the immune response in HF attempted to modulate the inflammatory response. Surprisingly, clinical studies targeting immune effectors were either neutral or even increased pre‐specified clinical endpoints, and some studies resulted in worsening of HF. This review discusses immune mediators involved in the pathogenesis and progression of HF and potential therapeutic applications targeting inflammation in HF. Besides more obvious settings featuring immune activation such as inflammatory or ischaemic cardiomyopathy, the relevance of immune activation in acute or chronic HF of other origins, including volume overload or valvular heart disease, is highlighted. Understanding how cell‐specific and molecular mechanisms of the immune response interfere with cardiac remodelling in HF may open new avenues to design biomarkers or druggable targets.
Model Studies for the Preparation of Oxepanes and Fused Compounds by Tandem [4+3] Cycloaddition/Ring‐Opening Metathesis/Cross Metathesis
Authors: Disetti Paolo , Piras Linda , Moccia Maria , Saviano Michele , Adamo Mauro F. A.
Published: September 2017

Functionalised medium‐sized ether rings were prepared in an efficient manner by [4+3] cycloaddition followed by ring‐opening metathesis. This procedure provided medium‐sized rings, which were shown to be useful for the assembly of fused bicyclic structures present in complex natural compounds. The potential of the chemistry described in this paper to be used in synthesis has been demonstrated by the preparation of functionalised large cyclic ethers and bicyclic structures.
Conversion of glucose‐xylose mixtures to pyruvate using a consortium of metabolically engineered Escherichia coli
Authors: Maleki Neda , Safari Mohammad , Eiteman Mark A.
Published: September 2017

Two strains of Escherichia coli were engineered to accumulate pyruvic acid from two sugars found in lignocellulosic hydrolysates by knockouts in the aceE, ppsA, poxB, and ldhA genes. Additionally, since glucose and xylose are typically consumed sequentially due to carbon catabolite repression in E. coli, one strain (MEC590) was engineered to grow only on glucose while a second strain (MEC589) grew only on xylose. On a single substrate, each strain generated pyruvate at a yield of about 0.60 g/g in both continuous culture and batch culture. In a glucose‐xylose mixture under continuous culture, a consortium of both strains maintained a pyruvate yield greater than 0.60 g/g when three different concentrations of glucose and xylose were sequentially fed into the system. In a fed‐batch process, both sugars in a glucose‐xylose mixture were consumed simultaneously to accumulate 39 g/L pyruvate in less than 24 h at a yield of 0.59 g/g.
Investigating the Predictive Validity ofTOEFL iBT®Test Scores and Their Use in Informing Policy in a United Kingdom University Setting
Authors: Harsch Claudia , Ushioda Ema , Ladroue Christophe
Published: September 2017

The project examined the predictive validity of theTOEFL iBT®test with a focus on the relationship between TOEFL iBT scores and students' subsequent academic success in postgraduate studies in one leading university in the United Kingdom, paying specific attention to the role of linguistic preparedness as perceived by students and tutors. We employed a mixed‐methods approach to enrich traditionally quantitatively oriented studies with a qualitative perspective. For the sample of 504 students who entered the university for postgraduate studies in the years 2011–2013 on the basis of a TOEFL iBT score, we analyzed the relation between TOEFL iBT scores and final academic award by correlation and regression analyses, taking into consideration discipline, nationality, and additional language support. For the qualitative strand, students entering the university in 2013 on the basis of a TOEFL iBT score were invited to complete questionnaires and interviews, as were their English for academic purposes and academic tutors. A total 48 students and 58 tutors participated, with 25 students and 36 tutors being interviewed at 3 points over the course of the year. Our findings show that students entering the university on the basis of TOEFL iBT scores feel well prepared and generally regard the test as an effective means of preparation for their academic studies in a U.K. setting. They cope well with linguistic demands, and a vast majority graduate successfully. Our findings support the appropriateness of the university's entrance policy with regard to setting minimum test score requirements, thus underpinning the predictive validity of TOEFL iBT in a U.K. setting.
Energy‐efficient multigroup communication
Authors: Riker André , Fonseca Carlos M. , Curado Marilia , Monteiro Edmundo
Published: September 2017

Wireless devices are widely used to monitor and control multiple groups within the context of machine‐to‐machine applications. The Constrained Application Protocol provides communication capabilities for applications that demand periodic monitoring of multiple groups. Because of the energy constraints of the devices used, a key challenge is to extend the network lifetime. Data aggregation solutions have been proposed to reduce the amount of network traffic and increase energy efficiency. However, for periodic monitoring of multiple groups, current data aggregation solutions do not exploit the potential of combining multiple payloads in a single message. In addition, solutions in literature are unable to take advantage of the communication interactions that occur when there is traffic originating from different groups. To fill this gap, this paper focuses on a nontraditional data aggregation approach, named two‐tier aggregation, that applies the idea of inserting many payloads in 1 message to efficiently gather data from multiple groups, introducing novelty on how the messages are assembled. An integer linear programming model is proposed to maximize the network lifetime in multiple group scenarios. The proposed formulation guarantees the energy efficiency of two‐tier aggregation and defines an upper bound for the heuristics. The evaluation shows the lifetime upper bound obtained by the proposed integer linear programming model on different network sizes and compares it to state‐of‐the‐art heuristic solutions.
Constructing a long‐term monthly climate data set in central Asia
Authors: Zhou Hang , Aizen Elena , Aizen Vladimir
Published: September 2017

We compiled and merged in situ observation data from several sources, creating a comprehensive unified monthly air temperature and precipitation data set with 457 stations in central Asia (CA). Stations with a valid data rate higher than 80% were selected, and the remaining gaps in selected station time series were filled with an iterative‐principal component analysis (PCA) gap‐filling method. The result is a gap‐filled station data set for the period 1951–2010, with 369 and 381 stations for air temperature and precipitation, respectively. The cross‐validation shows that the iterative‐PCA gap‐filling algorithm provides stable and trustworthy estimations of gaps, with mean root mean squared error (RMSE) of 0.03 °C (in the range of 0.01–0.13 °C) for air temperature, and mean RMSE of 0.60 mm (in the range of 0.10–1.99 mm) for precipitation. A gridded data set was created by interpolating the gap‐filled station data set with the geographically weighted regression method. Comparison of the gridded data set with the National Centers for Environmental Prediction (NCEP) reanalysis data set shows that though both data sets present the long‐term mean climate situation similarly, the gridded data set exhibits less annual and monthly variability. And the gridded data set has stronger correlations with stations time series than the reanalysis data set (mean correlations are 0.994 vs 0.975 for air temperature, and 0.787 vs 0.515 for precipitation), especially for precipitation in high mountain stations. The gridded data set is more suitable for climate and hydrological studies in CA, especially in high mountains regions.
A simple method to assess the added value using high‐resolution climate distributions: application to the EURO‐CORDEX daily precipitation
Authors: Soares Pedro M. M. , Cardoso Rita M.
Published: September 2017

Regional climate models (RCMs) are used with increasing resolutions seeking to represent in an improved way regional to local‐scale atmospheric phenomena. The EURO‐CORDEX simulations at 0.11° and simulations exploiting finer grid spacing approaching the convective‐permitting regimes are representative examples. These climate runs are computationally very demanding and do not always show improvements, which depend on the region, variable and object of study. The gains or losses associated with the use of higher resolution in relation to the forcing model (global climate model or reanalysis), or to different resolution RCM simulations, are widely known as added value. Its characterization is a long‐standing issue, and many different added‐value measures have been proposed.

In the current study, a new method is proposed to assess the added value of finer‐resolution simulations, in comparison to its forcing data or coarser‐resolution counterparts. This approach builds on a probability density function (PDF) matching score, giving a normalized measure of the difference between diverse resolution PDFs, mediated by the observational ones. The distribution added value (DAV) is an objective added‐value measure that can be applied to any variable, region or temporal scale, from hindcast or historical (non‐synchronous) simulations. The DAVs metric and its application to the EURO‐CORDEX hindcast daily precipitation data are presented here. Generally, the EURO‐CORDEX simulations at both resolutions (0.44° and 0.11°) display a clear added value in relation to ERA‐Interim, with maximum values around 30% in summer and 20% in the intermediate seasons. When both RCM resolutions are directly compared, only three of five models (0.11°) show added value, with a maximum of ∼10%. The regions with the larger DAVs are areas where convection is relevant, e.g. Alps and Iberia. When looking at the extreme PDF tail, the higher‐resolution improvement is generally greater than the low resolution for seasons and regions.
Does applying quantile mapping to subsamples improve the bias correction of daily precipitation?
Authors: Reiter Philipp , Gutjahr Oliver , Schefczyk Lukas , Heinemann Günther , Casper Markus
Published: September 2017

Quantile mapping (QM) is routinely applied in many climate change impact studies for the bias correction (BC) of daily precipitation data. It corrects the complete distribution, but does not correct for errors in the annual cycle. Therefore, QM is often applied separately to temporal subsamples of the data (e.g. each calendar month), which reduces the calibration sample size. The question arises whether this sample size reduction negates the benefit from applying QM to temporal subsamples. We applied four QM methods in a cross‐validation approach to 40 years of daily precipitation data from 10 regional climate model (RCM) hindcast runs, without and with (semi‐annual, seasonal, and monthly) subsampling. QM subsampling improved the BC of daily RCM precipitation; less distinct for independent data but considerably for the calibration data. The optimal subsampling timescale for the correction of independent data depended on the chosen QM method and ranged between semi‐annual and monthly. Overall, a sub‐annual QM improves the forcing for climate change impact studies and thus their reliability.
Sturm‐Picone comparison theorems for nonlinear impulsive differential equations with discontinuous solutions
Authors: Kayar Z. , Masiha S. K.
Published: September 2017

The nonlinear versions of Sturm‐Picone comparison theorem as well as Leighton's variational lemma and Leighton's theorem for regular and singular nonlinear impulsive differential equations with discontinuous solutions having fixed moments of impulse actions are established. Although discontinuity of the solutions causes some difficulties, these new comparison theorems cover the old ones where impulse effects are dropped.
Predicting Drug Concentration‐Time Profiles in Multiple CNS Compartments Using a Comprehensive Physiologically‐Based Pharmacokinetic Model
Authors: Yamamoto Yumi , Välitalo Pyry A. , Huntjens Dymphy R. , Proost Johannes H. , Vermeulen An , Krauwinkel Walter , Beukers Margot W. , van den Berg Dirk‐Jan , Hartman Robin , Wong Yin Cheong , Danhof Meindert , van Hasselt John G. C. , de Lange Elizabeth C. M.
Published: September 2017

Drug development targeting the central nervous system (CNS) is challenging due to poor predictability of drug concentrations in various CNS compartments. We developed a generic physiologically based pharmacokinetic (PBPK) model for prediction of drug concentrations in physiologically relevant CNS compartments. System‐specific and drug‐specific model parameters were derived from literature and in silico predictions. The model was validated using detailed concentration‐time profiles from 10 drugs in rat plasma, brain extracellular fluid, 2 cerebrospinal fluid sites, and total brain tissue. These drugs, all small molecules, were selected to cover a wide range of physicochemical properties. The concentration‐time profiles for these drugs were adequately predicted across the CNS compartments (symmetric mean absolute percentage error for the model prediction was <91%). In conclusion, the developed PBPK model can be used to predict temporal concentration profiles of drugs in multiple relevant CNS compartments, which we consider valuable information for efficient CNS drug development.
Epitaxial Growth of Thick Polar and Semipolar InN Films on Yttria‐Stabilized Zirconia Using Pulsed Sputtering Deposition
Authors: Kobayashi Atsushi , Oseki Masaaki , Ohta Jitsuo , Fujioka Hiroshi
Published: September 2017

We grew thick InN films on yttria‐stabilized zirconia (YSZ) substrates by high‐growth‐rate pulsed sputtering deposition. X‐ray diffraction analysis revealed that the in‐plane orientation distribution of the InN (0001) films on YSZ decreased as the film thickness increased. The edge dislocation density of the 9.0‐µm‐thick InN film grown at a rate of 6 µm h−1 is calculated to be 1.7 × 109 cm−2, and the atomically flat surface exhibited a step‐and‐terrace structure. In addition, the crystallinity of semipolar InN is improved by increasing the film thickness. These results indicate that high‐growth‐rate pulsed sputtering deposition can be used to prepare InN substrates for the fabrication of high‐speed electron devices and InGaN‐based, long‐wavelength light‐emitting devices.
Hysteresis of MnFePSi Spherical Powder Ensembles Studied by Magneto‐Optical Imaging
Authors: Funk Alexander , Zeilinger Michael , Dötz Florian , Soldatov Ivan , Schäfer Rudolf , Waske Anja
Published: September 2017

Temperature‐dependent magneto‐optical imaging is applied to study the thermal hysteresis of magnetocaloric MnFePSi spherical powder‐packed beds across their magneto‐elastic transition. Cooling and heating imaging series are used to analyze the transition of such a complex powder ensemble. The magnetization versus temperature behavior reconstructed from these local measurements shows very good agreement with integral measurements of the magnetization of the whole packed bed. Hence, local magneto‐optical imaging measurements represent the ensemble behavior well if the number of measurements is large enough. Furthermore, we analyzed the Curie temperature (TC) distribution of layers with different TC values and observed that the spread of TC within one layer is larger than the spacing between different layers, leading to a gradual switching behavior of the layer ensemble. Additionally, high resolution light microscopy was applied to observe the transition of individual particles, and correlate it to the local magnetic measurements.
Prioritizing key success factors of software projects using fuzzy AHP
Authors: Yaghoobi Tahere
Published: September 2017

The main purpose of most software projects is to build an effective and efficient product that satisfies the user's requirements under constraints of basic available resources. Thus, recognizing the critical features that may affect developing the application could be imperative. In this study, we apply the fuzzy analytic hierarchy process (AHP) to the issue of ordering key success factors (KSFs) for software development projects. To do this, we first simplified the constrained fuzzy AHP method, and then from systematic literature reviews, a preliminary list of potential KSFs that influences software development projects was identified and compiled. Subsequently, on the basis of the criteria of the frequency of citation in previous studies, closely related and similar functionality, the preliminary list was consolidated into a final set of 15 possible KSFs and considered at 4 perspectives of project management, development team, product, and processes. Pairwise comparisons, required by fuzzy AHP method, were done by 22 experienced professional internal stakeholders to determine the preference weights of factors and perspectives in terms of natural language expressions. The results reveal that project management has the highest importance in comparison with other 3 perspectives, and the factor of efficient project management skills/methodologies is the major. The procedure used in this paper is simple and accurate to implement and concludes both relative weights and rankings of alternatives in a fuzzy environment.
Isomeric Effects of Solution Processed Ladder‐Type Non‐Fullerene Electron Acceptors
Authors: Li Yongxi , Zhong Lian , Lin Jiu‐Dong , Wu Fu‐Peng , Bin Hai‐Jun , Zhang Zhanjun , Xu Lai , Jiang Zuo‐Quan , Zhang Zhi‐Guo , Liu Feng , Russell Thomas P. , Li Yongfang , Liao Liang‐Sheng , Forrest Stephen R.
Published: September 2017

The role of electronic structure and thin film morphology is investigated in determining charge transfer and electron coupling due to orbital interactions in two isomeric non‐fullerene acceptors with the structure of acceptor‐donor‐acceptor. Differences are found in the distribution of electron density of the highest occupied molecular and lowest unoccupied molecular orbitals, whose bonding interactions result in improved intermolecular interactions and hence, molecular stacking. When combined with a large band gap polymer donor, solution‐processed organic photovoltaic cells are demonstrated with power conversion efficiencies as high as 10.5 ± 0.4%, and with absorption extending to wavelengths of 800 nm. Due to strong internal organization driven by the planar molecular structure and strong intermolecular interactions, no post‐deposition processing such as solvent vapor or thermal annealing is required. To our knowledge, these are the highest efficiencies for as‐cast solution‐based devices employing non‐fullerene acceptors.
A sample carrier for measuring discrete powdered samples with an ITRAX XRF core scanner
Authors: Ohlendorf Christian
Published: September 2017

The elemental composition of discrete powdered sediment samples can be measured by the energy‐dispersive X‐ray fluorescence (XRF) system that is installed in XRF core scanners. Because an appropriate sample carrier for powdered samples is currently not available, for example, for the ITRAX XRF core scanner, such a carrier is presented in this technical note. The designed sample carrier can hold 30 sample cups with a volume of 0.88 cm3 each. A maximum of 5 sample carriers, that is, 150 samples, can be measured in one run. The sample cups and carriers are optimized for a measurement procedure with a step size of 5 mm and variable count times up to 100 s per sample. With this setting, data are collected from an area of 100 mm2 in the center of the sample thereby ensuring a good representativeness of the signal because potential sample inhomogeneity is accounted for. Because the described sample carrier system allows rapid element analyses of discrete powdered environmental samples with an XRF core scanner, it may in some cases represent a time‐ and cost‐efficient alternative to conventional XRF analyses.
Comparative Study of Interfacial and Biological Properties in d‐Glycerate‐Derived Surfactants
Authors: Sato Shun , Nagata Shota , Kitamoto Dai , Takahashi Yutaka , Kondo Yukishige , Habe Hiroshi
Published: September 2017

The effects of hydrophobic chain length on the interfacial and biological properties of diacyl d‐glyceric acid (d‐GA) sodium salts were evaluated based on interfacial tension analyses, dynamic light scattering (DLS), and antitrypsin activity. Of the four synthesized d‐GA‐derived surfactants [dihexanoyl d‐GA sodium salt (diC6GA‐Na), dioctanoyl d‐GA sodium salt (diC8GA‐Na), didecanoyl d‐GA sodium salt (diC10GA‐Na), and dilauroyl d‐GA sodium salt (diC12GA‐Na)], only those with C6, C8, and C10 acyl chains were investigated because diC12GA‐Na were insoluble at room temperature. Together with our previous results, surface tensions at the critical micelle concentration (CMC) were 33.9 mN/m for diC6GA‐Na, 25.5 mN/m for diC8GA‐Na, and 27.9 mN/m for diC10GA‐Na. Evaluation of assembly size via DLS and optical microscopy revealed that diC8GA‐Na and diC10GA‐Na formed large associates with average sizes ranging from 50 to 200 μm at concentrations 4–5 times greater than their CMC, whereas diC6GA‐Na did not form such associates. In tryptic hydrolysis studies using Nα‐benzoyl‐dl‐arginine‐4‐nitroanilide as a substrate, diC8GA‐Na exhibited an inhibitory effect on trypsin (trypsin specific activity: 0.26 ± 0.045 U/mg‐protein) greater than that of diC10GA‐Na (0.39 ± 0.10 U/mg‐protein), whereas diC6GA‐Na did not show antitrypsin activity. These results show that diC8GA‐Na was the most bioactive of the evaluated diacyl d‐glycerate surfactants.