bluuebunny/crossref_metadata_2025 huggingface dataset:
Resource Sustainability
Authors: Atwood David A.
Published: December 2015

In an analysis of the sustainability of elements, abundance must be considered alongside, and integrated with, other considerations such as the costs for production, environmental effects, and social impacts. This article outlines the basic concepts and components that must be considered for the sustainability of the lighter metals. This article attempts to provide an inorganic chemistry evaluation of the metals within the following metallurgical classifications: (i) non‐ferrous metals (Mg and Al), (ii) specialty metals (Li and Be), and (iii) common metals (Na, K, and Ca), and integrate them generally with the terminology of “Endangered Elements.”
Interrelationships between the Lightest Metals
Authors: Boyde Nicholas C. , Hanusa Timothy P.
Published: December 2015

As defined here, the “lightest” metals are those pretransition metals of lowest atomic number; that is, lithium, beryllium, sodium, magnesium, aluminum, potassium, and calcium (atomic no. 3–20); they have relatively low densities (0.53–2.70 g cm−3), but are not a set of the least dense metals. This article considers various attributes that link these metals together, starting with their primordial nucleosynthesis, and the problem of the cosmic abundance of lithium. It is believed that the relatively low natural abundance of both lithium and beryllium on the Earth is ultimately a consequence of peculiarities in their formation. Apart from these two, however, the “lightest” metals are extremely common elements on the Earth: Al is the most abundant metal in the crust (over 8% by weight), and the metals Ca, Mg, Na, and K constitute the fifth through eighth most abundant elements in the crust. It is perhaps not surprising that their ions (Ca2+, Mg2+, Na+, and K+) are the most encountered metal species in biological systems.

Although long used in the form of their compounds, the metals were not isolated as the free elements until the early nineteenth century (the last produced was beryllium, in 1828). They have been recognized as sharing similar chemical properties since the time they were discovered, leading to the articulation of the “(iso)diagonal rule”, which highlights the similarities between lithium and magnesium compounds, and between those of beryllium and aluminum. The metals' mechanical properties vary considerably; the stiffness of beryllium (it possesses the smallest Poisson ratio of any bulk element) leads to its supporting the highest velocity of sound of any metal; in contrast, lithium, sodium, and potassium are so soft that many of their elastic properties are difficult to measure accurately. Various alloys of the metals have extremely important properties, from the aluminum–magnesium alloys used in the aerospace industry to the beryllium copper alloys used to make nonsparking tools. Essential to life and indisputably important to modern society, the range of applications of “the lightest metals” can only be expected to grow during the twenty‐first century.
Low Oxidation State Chemistry
Authors: Hill Michael S.
Published: December 2015

The low oxidation state chemistry of the seven lightest metallic elements is described, with an emphasis on the introduction of bulky ligands to provide sufficient kinetic stability to allow the synthesis of well‐defined compounds, which are isolable under normal conditions of temperature and pressure. Although no stable low oxidation state compound of lithium has yet been described, a variety of sodium and potassium derivatives containing the alkali metal in the −1 oxidation have been unambiguously characterized. These “alkalides” display the general constitution, [LM]+[M]−(or [LM′]+[M]−in which the metals are dissimilar), where the stability toward disproportionation is provided by the presence of a cation‐encapsulating crown ether or cryptand ligand. In a similar manner, recent advances in Mg(I) chemistry that have allowed the synthesis of several stable compounds of the form LMg–MgL through the reduction of Mg(II) halide starting materials are dependent on the steric demands of chelating β‐diketiminato and guanidinato monoanions. A broad reaction chemistry, toward both organic and inorganic substrates, has begun to emerge for these soluble molecular two‐electron reductants that has allowed the isolation of a variety of unusual molecular types. No compounds of beryllium in an unambiguous oxidation state less than +2 have yet to be reported, however; Ca(I) is represented by a single paramagnetic “inverse sandwich” species in which the two alkaline earth centers are bridged by a sterically demanding arene dianion. In contrast to these relatively narrow advances for the lighter s‐block metals, aluminum displays a relatively rich low oxidation chemistry in which a plethora of formally Al(II) and Al(I) species have been described. The isolation of molecular Al–Al‐bonded compounds, which engage in similar two‐electron reduction reactivity to that now described for Mg(I), is again dependent on the selection of anionic supporting ligands with appropriate steric demands. Similarly, Al(I) species bearing a chemically active lone pair are now well precedented and have enabled the synthesis of a variety of oligomeric and monomeric species that are prone to oxidation to Al(III) or may be used as two‐electron bases toward a range of Lewis acid centers. Kinetically stabilized aluminum cluster species containing Al in formal oxidation states <1 have also been described through the reaction of metastable Al(I)X solutions with appropriately bulky ligands during the process of Al(I) disproportionation to Al(III) and metallic aluminum.
Cation–π Interactions
Authors: An Yi , Wheeler Steven E.
Published: December 2015

Cation–π interactions involving alkali metal cations are ubiquitous in modern chemical research, impacting everything from the structure of proteins to the activity of catalysis. Here, we survey the role of cation–π interactions involving alkali metal cations in chemistry, biology, and materials science, focusing on their structural and functional significance as well as means by which the strength of these noncovalent interactions can be tuned. In the process, we discuss recent advances in our understanding of the nature of these interactions through applications of spectroscopy and computational chemistry.
Beryllium Metal Toxicology: A Current Perspective
Authors: Civic Terence M.
Published: December 2015

Insoluble forms of beryllium comprise the entire commercial market for beryllium. As with many metals, the toxicity profile of soluble beryllium compounds differs from that of pure beryllium metal. However, this scientific fact is not generally recognized in assessments or reviews of beryllium metal toxicology. The literature does not generally reveal data for beryllium metal relative to genotoxicity, skin irritation, skin sensitization, or even oral toxicity. It is apparent that studies of toxicity endpoints observed in animals, including carcinogenicity, are almost entirely focused on soluble beryllium compounds with limited data on beryllium metal alone. It is also well known that the evidence relating to carcinogenicity of beryllium metal in humans is subject to uncertainty. This article is intended to provide the reader an evidence‐based perspective on beryllium metal toxicity and contrast that to the toxicity of soluble beryllium compounds.
Lithium‐Ion Batteries: Fundamentals and Safety
Authors: Buchmann Isidor
Published: December 2015

Rechargeable batteries with lithium metal on the anode can in principle provide extraordinarily high energy densities, but it was discovered in the mid‐1980s that cycling such batteries produced unwanted dendrites on the anode. The inherent instability of lithium metal, especially during charging, shifted research to a nonmetallic platform using lithium ions (Li
+
). Li‐ion batteries come in many varieties but differ most often in the cathode materials; common examples include lithium cobalt oxide (lithium cobaltate), lithium manganese oxide (also known as spinel or lithium manganate), lithium iron phosphate, as well as lithium nickel manganese cobalt (or NMC), and lithium nickel cobalt aluminum oxide (or NCA). Originally, coal‐derived coke was used as the anode, but since 1997, most Li‐ion manufacturers have shifted to graphite to attain a flatter discharge curve; graphite stores lithium ions well when the battery is charged and has long‐term cycle stability. Although lower in specific energy than lithium‐metal, Li‐ion technology is safe, provided cell manufacturers and battery packers follow appropriate measures in keeping voltage and currents to secure levels. Li‐ion is a low‐maintenance battery type, an advantage many other chemistries cannot claim. The nominal cell voltage of 3.60 V can directly power cell phones and digital cameras, offering simplifications and economic efficiencies over multicell designs. Cost reduction, increase in specific energy, and the absence of toxic material have served to make Li‐ion the universally accepted battery for portable applications, first in the consumer industry and now increasingly also in heavy industry, including electric powertrains for vehicles.
Li‐Ion Batteries and Beyond: Future Design Challenges
Authors: Hwa Yoon , Cairns Elton J.
Published: December 2015

Light metals have been widely used as electrode materials for batteries owing to their low standard redox potential, their low equivalent weight, large specific capacity, and great abundance. Both primary and secondary cells including light metals as electrode material have influenced all aspects of our lives, e.g., electrically operated toys, power tools, and portable electronics such as cell phones, smart pads, and laptop computers. Among all battery systems, rechargeable lithium (Li) ion cells have been used most widely in recent years owing to their high specific power, high energy density, and ambient temperature operation. However, Li‐ion cells are facing difficult challenges in satisfying the emerging market for advanced applications demanding high‐performance rechargeable batteries for applications such as electric vehicles, high‐performance portable electronics, and large‐scale electrical energy storage systems. Unfortunately, current Li‐ion cells cannot satisfy demands such as low cost, much improved safety, larger energy density, faster charge/discharge rates, and longer service life, so intensive effort is necessary to develop the next generation of cells. In this article, the limitations of current Li‐ion cells and various advanced materials for each component of the Li‐ion cell, in addition to other promising candidates for cells beyond Li ion, such as the Li/S cell and Na‐ and Mg‐based rechargeable cells, and metal/air cells are discussed.
High‐Pressure Synthesis of Hydrogen Storage Materials
Authors: Saitoh Hiroyuki , Takagi Shigeyuki , Aoki Katsutoshi , Orimo Shin‐ichi
Published: December 2015

Development of safe, efficient, and low‐cost hydrogen storage is a key technological issue that must be realized to generate a hydrogen‐based nonpolluting energy cycle and ultimately a feasible hydrogen economy. Lightweight hydrogen storage is also desired for automotive applications. As hydrogen becomes extremely reactive under high pressure, high‐pressure synthesis is a powerful method for fabricating novel hydrides. In situ synchrotron radiation X‐ray diffraction measurements enable optimal synthetic conditions to be determined quickly. Theoretical calculations can be used to predict the thermodynamic stability of the target material before initiating a high‐pressure synthesis, and they also provide crystallographic and electronic structural information about the target material. This article covers high‐pressure synthetic studies of novel metal hydrides using a cubic‐type multi‐anvil apparatus. The experimental details of high‐pressure generation, hydrogenation of metals under high pressure and high temperature, and in situ synchrotron radiation X‐ray diffraction measurements are presented. Synthetic studies on aluminum‐based interstitial hydrides and lithium‐containing complex hydrides are offered as successful examples of high‐pressure synthesis. Aluminum‐based interstitial hydrides, which were thought to be difficult to obtain, are shown to be accessible using high‐pressure techniques. Theoretically predicted Li4FeH6has been synthesized under high pressure and high temperature. In situ synchrotron radiation X‐ray diffraction measurements reveal the reaction conditions required for its formation and its thermodynamic stability.
One‐Dimensional Nanostructure‐Enhanced Catalysis
Authors: Wang Sibo , Ren Zheng , Guo Yanbing , Gao Pu‐Xian
Published: December 2015

The increasingly severe concerns about energy shortage and environmental pollution pose great challenges to the sustainable development of the global ecosystem and to human welfare. In search of solutions, during the past decade, nanostructure‐based catalysis has emerged as a major approach that can provide efficient energy utilization, conversion, and storage, as well as environmental remediation and cleaning. Specifically, one‐dimensional (1D) nanostructures, usually in the form of nanorods, nanotubes, and nanowires, have drawn great attention in catalysis owing to their superior properties relative to other nanostructured counterparts. The fast development of synthetic methods for producing 1D nanostructured materials has greatly contributed to the successful discovery and rational design of various energy and environmentally relevant catalysts with high activity, selectivity, and stability. For instance, in 1D heterostructured catalysts, the populated active sites due to their high surface‐to‐volume ratios and tailored synergistic effects between dissimilar nanostructured components lead to significant enhancement of catalytic performance. Moreover, the generation of three‐dimensional (3D) assemblies of 1D nanostructures makes 1D nanocatalysis a promising technology platform for various cost‐effective and sustainable industrial applications. In this article, we systematically introduce the latest progress on the synthesis of 1D nanostructured catalysts and their applications for air pollutant removal, photocatalytic water treatment and splitting, and electrocatalysis for energy conversion and storage. The nanostructures described here often rely critically on compounds of the lightest metals as supporting materials, either as pure oxides (i.e., alumina) or as mixed metal species.
Aryllithiums and Hetaryllithiums: Generation and Reactivity
Authors: Slocum D. W.
Published: December 2015

Aryllithiums and hetaryllithiums are of great utility to the chemical community. Not only do they serve as intermediates in the synthesis of various pharmaceuticals, but they also can be used in routes to polymers, inorganic complexes, natural products, and materials. Their versatility is well known.

In the late 1930s, simultaneous research discoveries of Georg Wittig and Henry Gilman began to appear. Eventually, these two pioneers delineated some of the parameters of both the ortho‐lithiation and halogen/lithium exchange reactions. Amplification of aspects of the ortho‐lithiation reaction over the next 25 years was provided by J. D. Roberts and C. R. Hauser with articulation of the “Complex‐Induced Proximity Effect” by Roberts and the directing groups –CH2NMe2and –CONHR by Hauser. Another 10 years passed before significant addition to the capabilities of the X/Li (X = halogen, halide) exchange took place. This is attributed to W. Parham and is known as the Parham cyclization. In many respects, this advancement in the overall usefulness of the halogen/lithium exchange has become a most important component of the incorporation of the exchange into synthetic procedures.

As details of the equilibria of alkyllithium reagents in various ether and hydrocarbon solvents began to emerge, advances in mechanistic understanding of both ortho‐lithiation and the exchange were made. These advances have made the production of aryllithiums and hetaryllithiums of significant value to the synthetic chemist. Recent discoveries promise to provide safer, more efficient process conditions, thereby making both protocols more attractive for scaled processes.

With all these advances, understanding of both reactions remains incomplete. Future research promises even greater control and fine‐tuning of the variables in each reaction such that they become of even greater utility. Although other main group metal and transition metal ortho‐metalations are known, the specificity and overall economy of aryllithium and hetaryllithium generation should bring about even greater involvement of these intermediates in future research and scaled production.
Occurrence of Magnesia Minerals and Production of Magnesium Chemicals and Metal
Authors: Shand Mark A.
Published: December 2015

The formation and occurrence of magnesium containing mineral sources is discussed with a focus on magnesite, magnesium brines, and dolomite. Production of synthetic magnesia from seawater and magnesium chloride containing brines is also outlined, all of which can be used as feedstocks for the production of magnesium metal. The production of metallic magnesium through the two primary production routes, namely metallothermic and electrolytic and their variants, is also discussed.
Lithium Pharmacology
Authors: Janicak Philip G. , Cutler Bradley R.
Published: December 2015

Lithium is an important treatment option for psychiatry. Although less clear, lithium's history also indicates a potential therapeutic role in other disorders. Presently, a lack of understanding regarding its mechanism(s) of action hamper clarification of this agent's optimal medical application and the development of more effective and better‐tolerated alternatives. Despite these issues, lithium provides practitioners and patients a potentially life‐saving therapeutic option in managing more severe mood disorders. This review considers the historical development of lithium; its pharmacokinetics; theoretical mechanism(s) of action; supportive clinical trial data, particularly for bipolar and related mood disorders; potential risks; and optimal use in clinical practice.
Group additive kinetic modeling for carbon‐centered radical addition to oxygenates and β‐scission of oxygenates
Authors: Paraskevas Paschalis D. , Sabbe Maarten K. , Reyniers Marie‐Françoise , Marin Guy B. , Papayannakos Nikos G.
Published: December 2015

A consistent set of 32 group additive values is determined for the Arrhenius parameters of carbon‐centered radical addition to oxygenates and the reverse β‐scission of oxygenate compounds, covering a wide temperature range (300–2500 K). These values are derived based on a training set of 66 reactions for which the Arrhenius parameters are calculated using the CBS‐QB3 method in the high‐pressure limit, including corrections for hindered internal rotation. The accuracy of the model is established by comparing model predictions with an ab initio (AI) validation set containing 24 reactions. The mean factor of deviation between the group additively calculated and the AI rate coefficients is 3, for both radical additions and β‐scissions. Therefore, the developed group additive model, constituting an extension of the existing model for carbon‐centered radical additions and β‐scissions of hydrocarbons, can be safely applied for an accurate prediction of kinetics of the corresponding reactions involving oxygenate compounds. © 2015 American Institute of Chemical Engineers AIChE J, 62: 802–814, 2016
Microstructure relaxation process of polyhexafluoropropylene after swelling in supercritical carbon dioxide
Authors: Belov N. A. , Alentiev A. Yu. , Ronova I. A. , Sinitsyna O. V. , Nikolaev A. Yu. , Zharov A. A.
Published: December 2015

This paper studies the process of relaxation of a polymer after swelling in supercritical carbon dioxide. Polyhexafluoropropylene (PHFP) was chosen as the object for investigation. The relaxation process was monitored by a change of the permeability coefficients for a number of gases. Thin polymeric films of PHFP were modified by different treatments: drying to a constant weight, annealing at a temperature slightly higher than the glass‐transition temperature, and swelling in supercritical carbon dioxide. The permeability coefficients of six gases, He, H2, O2 N2, CO2, and CH4, were measured after each stage of the treatment. It was shown that the permeability coefficients in the films were increased by 2.4 times for He, 3.6 for H2, 5.9 for O2, 8.1 for N2, 6.7 for CO2, and 10.9 for methane. The permeability coefficients of the same gases were measured 50 days later after swelling in supercritical carbon dioxide. A decrease in the permeability coefficient demonstrated that the relaxation process had taken place. Nevertheless, the values exceeded the initial ones for annealed samples by 2.0 times for He, 2.4 for H2, 1.8 for O2, 1.7 for N2, 1.7 for CO2, and 1.3 for methane. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43105.
Preparation and performance analysis of barium titanate incorporated in corn starch‐based polymer electrolytes for electric double layer capacitor application
Authors: Teoh K. H. , Lim Chin‐Shen , Liew Chiam Wen , Ramesh S.
Published: December 2015

Polymer electrolyte membranes composing of corn starch as host polymer, lithium perchlorate (LiClO4) as salt, and barium titanate (BaTiO3) as composite filler are prepared using solution casting technique. Ionic conductivity is enhanced on addition of BaTiO3 by reducing the crystallinity and increasing the amorphous phase content of the polymer electrolyte. The highest ionic conductivity of 1.28 × 10−2 S cm−1 is obtained for 10 wt % BaTiO3 filler in corn starch‐LiClO4 polymer electrolytes at 75°C. Glass transition temperature (Tg) of polymer electrolytes decreases as the amount of BaTiO3 filler is increased, as observed in differential scanning calorimetry analysis. Scanning electron microscopy and thermogravimetric analysis are employed to characterize surface morphological and thermal properties of BaTiO3‐based composite polymer electrolytes. The electrochemical properties of the electric double‐layer capacitor fabricating using the highest ionic conductivity polymer electrolytes is investigated using cyclic voltammetry and charge‐discharge analysis. The discharge capacitance obtained is 16.22 F g−1. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43275.
Polypropylene composites obtained from self‐reinforced hybrid fiber system
Authors: Andrzejewski Jacek , Tutak Nicole , Szostak Marek
Published: December 2015

The purpose of the study was to obtain a composite material with the self‐reinforced structure, which processing provide increased mechanical properties. The composites used in presented work were prepared from the two types of fiber mixtures, both were based on polypropylene fibers, the difference was in used cellulose or wood flour filler. Composites were prepared using the hot compaction method. The presented research describes the effect of the composite composition and processing conditions. The results include the static tension measurements, tensile impact tests and thermal analysis, including: DSC and DMTA. The structure has been studies using the SEM observations. Results of presented studies confirm the self‐reinforcing effect in obtained hybrid composites. It provides in the comparison to the standard wood polymer composites to the higher level of material reinforcement with lower amount of natural filler. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43283.
Glass fiber coated with graphene constructed through electrostatic self‐assembly and its application in poly(lactic acid) composite
Authors: Yin Xiande , Bao Jianjun
Published: December 2015

A method to construct glass fiber/graphene material via the electrostatic self‐assembly was proposed. The graphene oxide (GO) nanosheets were firstly prepared from graphite according to Hummer's methods. Oppositely charged GO is successfully introduced to the surface of the GF cationized by 3‐aminopropyltriethoxysilane (APTES) treatment in the solution with mild agitation. Sequently, glass fibers coated with graphene (GF/CRG) were obtained after chemical reduction. The graphene content was characterized by TGA and XPS tests and the value of about 0.7 wt % was obtained. Composites of poly(lactic acid) and GF/CRG were prepared through melt blending. Thermogravimetric analysis (TGA) results shows that more than 50% graphene remains on the surface of GF after processing, which indicates a strong binding between GF and graphene. GF/CRG has significant influences on crystallization and mechanical property of PLA: the crystallinity of PLA increases from 27.61 to 51.29%; the tensile strength of the PLA–GF/CRG composite is about 63% larger than the pure PLA at the GF/CRG content of 10 wt %. This new method can apply to making composites with high performance. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43296.
The effects of research resources on international collaboration in the astronomy community
Authors: Chang Han‐Wen , Huang Mu‐Hsuan
Published: December 2015

This study examines whether an institution's research resources affect its centrality and relationships in international collaboration among 606 astronomical institutions worldwide. The findings support our theoretical hypotheses that an institution's research resources are positively related to its central position in the network. Astronomical institutions with superior resources, such as being equipped with international observational facilities and having substantial research manpower, tend to have more foreign partners (high degree centrality) and play an influential role (high betweenness centrality) in the international collaboration network. An institution becomes more and more active in international collaborations as its research population expands. In terms of the relationship, which is captured by an actor institution's co‐authorship preference for each partner in the network, the effect of research resources is not as significant as expected. We found that astronomical institutions are not necessarily preferentially co‐authoring with partners that have better research resources. In addition, this study indicates that geographic closeness (or “geographic proximity”) largely affects the occurrence of international collaboration. The investigated institutions apparently prefer partners from neighboring countries. This finding gives an indication of the phenomenon of “regional homophily” in the international collaboration network.
Understanding eye movements on mobile devices for better presentation of search results
Authors: Kim Jaewon , Thomas Paul , Sankaranarayana Ramesh , Gedeon Tom , Yoon Hwan‐Jin
Published: December 2015

Compared to the early versions of smart phones, recent mobile devices have bigger screens that can present more web search results. Several previous studies have reported differences in user interaction between conventional desktop computer and mobile device‐based web searches, so it is imperative to consider the differences in user behavior for web search engine interface design on mobile devices. However, it is still unknown how the diversification of screen sizes on hand‐held devices affects how users search. In this article, we investigate search performance and behavior on three different small screen sizes: early smart phones, recent smart phones, and phablets. We found no significant difference with respect to the efficiency of carrying out tasks, however participants exhibited different search behaviors: less eye movement within top links on the larger screen, fast reading with some hesitation before choosing a link on the medium, and frequent use of scrolling on the small screen. This result suggests that the presentation of web search results for each screen needs to take into account differences in search behavior. We suggest several ideas for presentation design for each screen size.
Statistically related coupled modes of South Asian summer monsoon interannual variability in the tropics
Authors: Syed F. S. , Kucharski F.
Published: December 2015

Statistically coupled patterns of South Asian Summer Monsoon (SASM) interannual variability in the tropical oceans have been explored. Maximum covariance analysis (MCA) performed between global tropical sea surface temperature (SST) and SASM precipitation shows that El‐Niño southern oscillation (ENSO) is the leading mode in the tropics, whereas the eastern pole of the Indian Ocean Dipole contributes to the second global mode and is the leading mode in the Indian Ocean. South tropical Atlantic SST variability is contributing to the second and third mode in the tropics and is the leading mode in the tropical Atlantic MCA coupled with SASM.
Investigation of an extreme Koshava wind episode of 30 January–4 February 2014
Authors: Romanić Djordje , Ćurić Mladjen , Zarić Miroljub , Lompar Miloš , Jovičić Ilija
Published: December 2015

An extreme Koshava episode (EKE) from 30 January to 4 February 2014 has been studied. Koshava is a local windstorm in Southeast Europe. EKE was characterized by wind gusts above 45 m s−1 and deep snowdrifts. Strong Eurasian anticyclone in combination with large temperature gradient between the anticyclone region and the Mediterranean caused the EKE. The anticyclone had the probability of occurrence of 0.1%. Koshava layer was either statically stable or adiabatic. The event was numerically modelled using two mesoscale models: WRF‐NMM and NMMB. Wind directions were forecasted more accurately than the mean speed and gusts.
Integrated optimization of location and signal timings for midblock pedestrian crosswalk
Authors: Yu Chunhui , Ma Wanjing , Yang Xiaoguang
Published: December 2015

Finding the optimal location and signal timing plan is one of the most critical operational issues for a signalized midblock crosswalk on an arterial section, which is increasingly being installed in highly populated areas in developing countries such as China. This paper presents a multiobjective optimization model and an efficient solution algorithm for a one‐ or two‐stage midblock crosswalk on an arterial section. The proposed model aims to produce the optimal location and corresponding signal settings to balance the trade‐off between pedestrian delays and vehicular bandwidth when the signals of the crosswalk and adjacent intersections are coordinated. The proposed model has three distinguishing features: (i) the costs for both pedestrians and vehicles are considered in a unified framework; (ii) the location and signal settings of the midblock crosswalk are simultaneously optimized; and (iii) a multiobjective optimization approach is developed to study the effectiveness of the midblock crosswalk under conditions in which the priorities between pedestrian and vehicle flows differ. A nondominated sorting genetic algorithm II (NSGA II)‐based algorithm is developed to solve the model efficiently. The results of the case study showed that the proposed model would help traffic practitioners, researchers, and authorities properly locate and signalize a one‐ or two‐stage midblock pedestrian crosswalk on an arterial section. Copyright © 2015 John Wiley & Sons, Ltd.
Binder‐ and Carbon‐free Porous Thick Tin Foil Electrode via a Spontaneous Electrochemical and Chemical Process
Authors: Mun Junyoung , Ryu Ji Heon
Published: December 2015

In this work, a porous Sn foil electrode that is free of binder and conducting agent is prepared for use in lithium ion batteries via a spontaneous method that consists of electrochemical lithiation followed by a chemical de‐lithiation process. In lithium ion battery, conventional Sn foil cannot electrochemically accommodate lithium ions despite the low current density of 50 mA/g used for cycling because of the high kinetic hindrances resulting from the poor diffusion of lithium between the electrolyte and the electrode. In this work, the surface morphology of Sn foil is modified to be porous to ensure the lithium diffusion pathway from the electrolyte to the electrode using a facile method that does not require special electrochemical equipment. The obtained porous Sn foil exhibits a voltage plateau that corresponds to Li/Sn alloying and a reversible specific capacity that exceeds 300 mAh/g. The crystal structures, surface morphologies, and electrochemical characteristics of the prepared samples are investigated using X‐ray diffraction, scanning electron microscopy, and electrochemical analyses.
The comparative pharmacokinetics of four bioactive ingredients after administration of Ramulus Cinnamomi–Radix Glycyrrhizae herb pair extract, Ramulus Cinnamomi extract and Radix Glycyrrhizae extract
Authors: Wang Shengnan , Sun Lijiao , Gu Liqiang , Zhang Yuanyuan , Zhao Simin , Zhao Long‐shan , Bi Kai‐shun , Chen Xiaohui
Published: December 2015

Ramulus Cinnamomi (RC)–Radix Glycyrrhizae (RG) is a classic herb pair, which is commonly used as a fixed form to treat cardiovascular disease in the clinic. Our work aimed to compare the pharmacokinetic difference of cinnamic acid, liquiritin, isoliquiritigenin and glycyrrhetinic acid in rats after oral administration of the RC–RG herb pair extracts [Guizhigancao Decoction (GGD) and Lingguizhugan Decoction (LGZGD)] and the single RC or RG extract. A HPLC‐MS method was developed and validated to study comparative pharmacokinetics. The pharmacokinetic parameters (Cmax, AUC, MRT) of four compounds between the RC–RG herb pair group and the single herb (RC or RG) group showed significant differences (p < 0.05). Compared with the single herb (RC or RG) group, higher peak concentration, slower elimination and larger exposure could be observed after giving the RC–RG herb‐pair extracts. The pharmacokinetic differences might indicate the relativity of remedy in the RC–RG herb pair and provide scientific information for rational administration of the drug in the clinic. Copyright © 2016 John Wiley & Sons, Ltd.
Growth of human mesenchymal stem cells (MSCs) on films of enzymatically modified chitosan
Authors: Aljawish Abdulhadi , Muniglia Lionel , Chevalot Isabelle
Published: December 2015

Mesenchymal stem cells (MSCs) are known to be an attractive cell source for tissue engineering and regenerative medicine. One of the main limiting steps for clinical use or biotechnological purposes is the expansion step. The research of compatible biomaterials for MSCs expansion is recently regarded as an attractive topic. The aim of this study was to create new functional biomaterial for MSCs expansion by evaluating the impact of chitosan derivative films modified by enzymatic approach. First, chitosan particles were enzymatically modified with ferulic acid (FA) or ethyl ferulate (EF) under an eco‐friendly procedure. Then, films of chitosan and its modified derivatives were prepared and evaluated by physicochemical and biological properties. Results showed that the enzymatic grafting of FA or EF onto chitosan significantly increased hydrophobic and antioxidant properties of chitosan films. The MSCs cell viability on chitosan derivative films also increased depending on the film thickness and the quantity of grafted phenols. Furthermore, the cytotoxicity test showed the absence of toxic effect of chitosan derivative films towards MSCs cells. Cell morphology showed a well attached and spread phenotype of MSCs cells on chitosan derivative films. On the other hand, due to the higher phenol content of FA‐chitosan films, their hydrophobic, antioxidant properties and cell adhesion were improved in comparison with those of EF‐chitosan films. Finally, this enzymatic process can be considered as a promising process to favor MSCs cell growth as well as to create useful biomaterials for biomedical applications especially for tissue engineering. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:491–500, 2016
Modular Equipment for Chemical Process Development and Small‐Scale Production in Multipurpose Plants
Authors: Kockmann Norbert
Published: December 2015

Small‐scale, continuous‐flow processes are currently discussed in the chemical industry for rapid process development and manufacturing of small product amounts. This contribution describes an equipment toolbox system for continuously operated chemical reactors consisting of microfluidic chip or plate reactors for rapid mixing, capillary or coil tube reactors for defined mixing and residence time, as well as continuously stirred tank reactors. The involved phases of the physico‐chemical system determine the successfully deployed elements or modules and therefore enable the setup of a flexible multipurpose plant. The platform strategy with modules of similar flow throughput as well as temperature or pressure range allow for consistent scale‐up. Several examples show the current development level, while first experiences from plant engineering indicate the implementation status and open issues.
Enantioselective Benzylic Hydroxylation Catalysed by P450 Monooxygenases: Characterisation of a P450cam Mutant Library and Molecular Modelling
Authors: Eichler Anja , Gricman Łukasz , Herter Susanne , Kelly Paul P. , Turner Nicholas J. , Pleiss Jürgen , Flitsch Sabine L.
Published: December 2015

Cytochrome P450 monooxygenases can catalyse the stereoselective C−H activation of a very broad range of substrates. Prediction and control of enantioselectivity of this enzyme class is of great interest for the synthesis of high‐value chiral molecules. Here we have used a combination of molecular dynamics simulations and experimental screening to study the enantioselectivity of a library of active‐site mutants of chimeric P450cam‐RhFRed towards the benzylic hydroxylation of structurally related regioisomers of ethylmethylbenzene. Small variations either in substrate structure or in enzyme active site architecture were shown to lead to dramatic changes in enantioselectivity; this was broadly in agreement with computational predictions. In addition to validating computational approaches, these studies have provided us with a deeper understanding of effects that might control stereoselectivity in these biooxidation reactions.
Experience and complications associated with use of guide extension catheters in percutaneous coronary intervention
Authors: Waterbury Thomas M. , Sorajja Paul , Bell Malcolm R. , Lennon Ryan J. , Mathew Verghese , Singh Mandeep , Sandhu Gurpreet S. , Gulati Rajiv
Published: December 2015

Objectives

To investigate the utility and safety of the GuideLiner “mother‐and‐child” catheter system during transradial and transfemoral percutaneous coronary intervention (PCI).

Background

In patients with complex coronary anatomy, stent delivery can be challenging and result in procedural failure and complications. The GuideLiner is a coaxial guide extension system designed to enable deep vessel engagement and facilitate device delivery. The purpose of this study was to evaluate procedural success and safety in a series of GuideLiner‐facilitated PCI.

Methods

Single center retrospective study of PCI utilizing the GuideLiner catheter between February 2010 and October 2014. Patients who underwent PCI without GuideLiner use during the same time period were used as controls for comparison.

Results

A total of 363 cases of GuideLiner‐facilitated PCI were identified from 6,088 unique PCI procedures performed during this same time period. Patients in the GuideLiner group were older (mean age 71.5 vs. 67.8, P < 0.001) and had more multivessel disease (72% vs. 63%, P = 0.001) compared with controls. Type C lesions were present in 78% of GuideLiner cases. Procedural success resulting in successful device delivery with the GuideLiner catheter was 80.2%. Stent deformation associated with GuideLiner use occurred in 2.2% (8/363), with the incidence of this complication decreasing over device iterations. Coronary dissection attributed to GuideLiner occurred in 3.3% (12/363) and became less frequent over the study period.

Conclusions

In this consecutive series of GuideLiner supported PCI, the guide extension system enabled procedural success in the majority. A decline in device‐associated complications over time may be attributed to operator learning curve, patient selection, and improvement in catheter design. © 2015 Wiley Periodicals, Inc.
Preliminary results of adjunctive use of endoanchors in the treatment of short neck and pararenal abdominal aortic aneurysms
Authors: Galiñanes Edgar Luis , Hernandez Eduardo , Krajcer Zvonimir
Published: December 2015

Objectives

To present our initial experience with the use of EndoAnchors for endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs) with little to no infrarenal landing zone.

Background

EndoAnchors have been reported to assist in the prevention and treatment of type 1a endoleaks in patients with hostile aortic necks who undergo EVAR.

Methods

Between July 2013 and July 2014, nine patients with AAAs and short proximal aortic necks (i.e., 0–10 mm in length) underwent EVAR. In five patients, utilization of the chimney graft technique was necessary. A mean of 2.5 (range 1–4) visceral vessels underwent chimney graft. The prophylactic use of EndoAnchors was utilized in all 9 patients. The decision to use the EndoAnchors was made in the preoperative planning phase.

Results

Technical success was achieved in 100% of cases. In two cases, type 1a endoleaks were noted before the deployment of any EndoAnchors. In both cases, a final angiogram depicted resolution of the type 1a endoleak after insertion of the EndoAnchors. Mean follow‐up time was 8 months. At 30 days, 3 months, and 6 months, 100% of the endografts remained patent and free from type 1a endoleaks. No adverse renal complications or mortality was reported.

Conclusions

EndoAnchors are an applicable adjunct to EVAR as treatment for short infrarenal neck and pararenal AAAs. Further investigations are needed to determine the durability of this novel application. © 2015 Wiley Periodicals, Inc.
A hospital‐wide system to ensure rapid treatment time across the entire spectrum of emergency percutaneous intervention
Authors: Khot Umesh N. , Johnson‐Wood Michele L. , VanLeeuwen Robert , Ramsey Curtis , Khot Monica B.
Published: December 2015

Objectives

This study's aim was to describe a hospital‐wide system to deliver rapid door‐to‐balloon time across the entire spectrum of emergency percutaneous intervention.

Background

Many patients needing emergency PCI are excluded from door‐to‐balloon public reporting metric; these groups do not achieve door‐to‐balloon times ≤90 min and have increased mortality rates. Methods: We prospectively implemented a protocol for patients with STEMI or other emergency indication for catheterization mandating (1) emergency department physician or cardiologist activation of the catheterization lab and (2) immediate patient transfer to an immediately available catheterization lab by an in‐house nursing transfer team.

Results

From September 1, 2005 to December 31, 2008, 526 consecutive patients underwent emergency PCI. Median door‐to‐balloon time was 68 min with 85.7% ≤90 min overall. Important subgroups included primary emergency department (62.5 min), cardiorespiratory arrest (71 min), cardiogenic shock (68 min), need for temporary pacemaker or balloon pump (67 min), initial ECG without ST‐elevation (66.5 min), transfer from another ED (84 min), in‐hospital (70 min), and activation indications other than STEMI (68 min). Patients presenting to primary ED and in transfer were compared to historical controls. Treatment ≤90 min increased (28%–85%,P < 0.0001). Mean infarct size decreased, as did hospital length‐of‐stay and admission total hospital costs. Acute myocardial infarction all‐cause 30‐day unadjusted mortality and risk‐standardized mortality ratios were substantially lower than national averages.

Conclusion

A hospital‐wide systems approach applied across the entire spectrum of emergency PCI leads to rapid door‐to‐balloon time, reduced infarct size and hospitals costs, and low myocardial infarction 30‐day all‐cause mortality. © 2015 Wiley Periodicals, Inc.
SCAI expert consensus statement: Evaluation, management, and special considerations of cardio‐oncology patients in the cardiac catheterization laboratory (Endorsed by the Cardiological Society of India, and Sociedad Latino Americana de Cardiologıa Intervencionista)
Authors: Iliescu Cezar , Grines Cindy L. , Herrmann Joerg , Yang Eric H. , Cilingiroglu Mehmet , Charitakis Konstantinos , Hakeem Abdul , Toutouzas Konstantinos , Leesar Massoud A. , Marmagkiolis Konstantinos
Published: December 2015

In the United States alone, there are currently approximately 14.5 million cancer survivors, and this number is expected to increase to 20 million by 2020. Cancer therapies can cause significant injury to the vasculature, resulting in angina, acute coronary syndromes (ACS), stroke, critical limb ischemia, arrhythmias, and heart failure, independently from the direct myocardial or pericardial damage from the malignancy itself. Consequently, the need for invasive evaluation and management in the cardiac catheterization laboratory (CCL) for such patients has been increasing. In recognition of the need for a document on special considerations for cancer patients in the CCL, the Society for Cardiovascular Angiography and Interventions (SCAI) commissioned a consensus group to provide recommendations based on the published medical literature and on the expertise of operators with accumulated experience in the cardiac catheterization of cancer patients. © 2015 Wiley Periodicals, Inc.
Enhanced Aerogen–π Interaction by a Cation–π Force
Authors: Miao Junjian , Song Bo , Gao Yi
Published: December 2015

The interaction between a noble gas atom and an aromatic π‐electron system, which mainly originates from the London dispersion force, is very weak and has not attracted enough attention yet. Herein, we reported a type of notably enhanced aerogen–π interaction between cation–π systems and noble gas atoms. The binding strength of a divalent cation–π system with a xenon atom is comparable to a moderate hydrogen bond (up to ca. 7 kcal mol−1), whereas krypton and argon atoms produce slightly weaker interactions. Energy‐decomposition analysis reveals that the induction interaction is responsible for the stabilization of divalent cation–π⋅Xe species besides the dispersion interaction. Our results might be helpful to increase the understanding of some unsolved mysteries of aerogens.
Scaffold Optimisation of Tetravalent Antagonists of the Mannose Binding Lectin
Authors: Goti Giulio , Palmioli Alessandro , Stravalaci Matteo , Sattin Sara , De Simoni Maria‐Grazia , Gobbi Marco , Bernardi Anna
Published: December 2015

Antagonists of mannose binding lectin (MBL) have shown a protective role against brain reperfusion damage after acute ischemic stroke. Here we describe the design and streamlined synthesis of glycomimetic MBL antagonists based on a new tetravalent dendron scaffold. The dendron was developed by optimisation of a known polyester structure previously demonstrated to be very efficient for ligand presentation to MBL. Replacement of a labile succinyl ester bond with a more robust amide functionality, use of a longer and more hydrophilic linker, fast modular synthesis and orthogonal functionalisation at the focal point are the main features of the new scaffold. The glycoconjugate constructs become stable to silica gel chromatography and to water solutions at physiological pH, while preserving water solubility and activity in an SPR assay against the murine MBL‐C isoform. Higher‐order constructs were easily assembled, as demonstrated by the synthesis of a 16‐valent dendrimer, which leads to two orders of magnitude increase in activity over the tetravalent version against MBL‐C.