bluuebunny/crossref_metadata_2025 huggingface dataset:
Tandem Coupling of Azide with Isonitrile and Boronic Acid: Facile Access to Functionalized Amidines
Authors: Zhang Zhen , Huang Baoliang , Qiao Guanyu , Zhu Liu , Xiao Fan , Chen Feng , Fu Bin , Zhang Zhenhua
Published: March 2017

Amidine is a notable nitrogen‐containing structural motif found in bioactive natural products and pharmaceuticals. Herein, a novel rhodium(I)‐catalyzed tandem reaction of readily accessible azides with isonitriles and boronic acids via a carbodiimide intermediate is achieved. This protocol offers an alternative approach toward N‐sulfonyl‐, N‐acyl‐, and N‐ phosphoryl‐functionalized, as well as general N‐aryl and N‐alkyl amidines with broad substrate scope. In addition, functionalized guanidines can also been synthesized when amines are used instead. The accomplishment of estrone‐derived amidine and glibenclamide bioisosteres further reveals the practical utility of this strategy.
Brønsted Acid Catalysis in Visible‐Light‐Induced [2+2] Photocycloaddition Reactions of Enone Dithianes
Authors: Brenninger Christoph , Pöthig Alexander , Bach Thorsten
Published: March 2017

1,3‐Dithiane‐protected enones (enone dithianes) were found to undergo an intramolecular [2+2] photocycloaddition under visible‐light irradiation (λ=405 nm) in the presence of a Brønsted acid (7.5–10 mol %). Key to the success of the reaction is presumably the formation of colored thionium ions, which are intermediates of the catalytic cycle. Cyclobutanes were thus obtained in very good yields (78–90 %). It is also shown that the dithiane moiety can be reductively or oxidatively removed without affecting the photochemically constructed ring skeleton.
Comparative study of PEO and PVA hydrogels for removal of methylene blue dye from wastewater
Authors: Teixeira Raquel S. P. , Correa Rodrigo J. , Bello Forero Josué S. , Silva Mariana G. S. , Oliveira Ronaldo C. S. , Souza Rodrigo S.
Published: March 2017

In this study, poly(vinyl alcohol) (PVA) and poly(ethylene oxide) (PEO) hydrogels were synthesized and evaluated as adsorbent for dye removal from wastewater using methylene blue (MB) in aqueous solution as probe. PEO samples were photochemically prepared by varying irradiation time (1–16 h), while PVA samples were synthetized with different concentration of glutaraldehyde (GA) (0.03–0.48%). The obtained hydrogels were obtained through the analysis of a swelling test, scanning electron microscopy, and adsorption studies. PEO hydrogels adsorption capacity was dependent on the irradiation time, while the PVA hydrogel adsorption capacity reduces with GA concentration. Both hydrogels demonstrated a Langmuir isotherm adsorption model at the equilibrium and pseudo‐second order kinetic fits properly. pH studies showed that when pH reaches 12, the adsorbed MB amount is close to 8 and 2 times higher than pH = 2 both hydrogels. Photochemical preparation of hydrogels shows an easier way of tuning their properties in order to maximize dye removal. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45043.
Synthesis and CO2 adsorption behavior of amine‐functionalized porous polystyrene adsorbent
Authors: Liu Fenglei , Chen Shuixia , Gao Yanting , Xie Yufang
Published: March 2017

A solid amine adsorbent was prepared by modifying a porous polystyrene resin (XAD‐4) with chloroacetyl chloride through a Friedel–Crafts acylation reaction, followed by aminating with tetraethylenepentamine (TEPA). The adsorption behavior of CO2 from a simulated flue gas on the solid amine adsorbent was evaluated. Factors that could determine the CO2 adsorption performance of the adsorbents such as amine species, adsorption temperature, and moisture were investigated. The experimental results showed that the solid amine adsorbent modified with TEPA (XAD‐4‐TEPA), which had a longer chain, showed an amine efficiency superior to the other two amine species with shorter chains. The CO2 adsorption capacity decreased obviously as the temperature increased because the reaction between CO2 and amine groups was an exothermic reaction, and its adsorption amount reached 1.7 mmol/g at 10 °C in dry conditions. The existence of water could significantly increase the CO2 adsorption amount of the adsorbent by promoting the chemical adsorption of CO2 on XAD‐4‐TEPA. The adsorbent kept almost the same adsorption amount after 10 cycles of adsorption–desorption. All of these results indicated that amine‐functionalized XAD‐4 resin was a promising CO2 adsorbent. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45046.
Dehydration of industrial isopropanol (IPA) waste by pervaporation and vapor permeation membranes
Authors: Zuo Jian , Hua Dan , Maricar Verma , Ong Yee Kang , Chung Tai‐Shung
Published: March 2017

We have investigated the feasibility of using polymeric membranes for the dehydration of industrial isopropanol (IPA) waste from MSD International GmbH by pervaporation and vapor permeation in this study. Four types of membranes were employed. They were (1) thin‐film composite hollow fiber consisting of a polyamide selective layer and a polyetherimide Ultem® substrate, (2) dual‐layer hollow fiber comprising an outer cellulose triacetate (CTA) layer and an inner Ultem® substrate, and (3) two commercially available Sulzer flat‐sheet membranes. The dual‐layer hollow fiber shows the most balanced separation performance in terms of flux and separation factor for the dehydration of industrial IPA waste because it has a porous substructure and a thin dense selective layer. Under vapor permeation tests at 125 °C, it has a flux of 13.41 kg/m2 h and a separation factor of 1332. This study demonstrates the great potential of using polymeric membranes to dehydrate industrial IPA waste for pharmaceutical and electronic industries. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45086.
Exploration on polypropylene carbonate polymer for gel polymer electrolyte preparation and dye‐sensitized solar cell application
Authors: Farhana N. K. , Khanmirzaei Mohammad H. , Ramesh S. , Ramesh K.
Published: March 2017

Gel polymer electrolytes (GPEs) with incorporation of polypropylene carbonate (PPC) polymer and different weight percentages of sodium iodide (NaI) salt are prepared. Ethylene carbonate and propylene carbonate are used as plasticizers. The maximum ionic conductivity of 2.01 mS cm−1 is achieved at room temperature. Temperature‐dependent ionic conductivity study is performed. The GPEs are studied for structural properties using Fourier transform infrared (FTIR). The FTIR analysis confirms that complexation between PPC and NaI has occurred. By using GPEs, dye‐sensitized solar cells (DSSC) are fabricated under the one Sun light intensity. The highest energy conversion efficiency of 6.38% is achieved with incorporation of 60 wt % of NaI. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45091.
Radiological and Microsurgical Anatomy for Variation of the Mandible: Comparative Study of Human and Macaca fascicularis
Authors: Iwanaga Joe , Watanabe Koichi , Saga Tsuyoshi , Tabira Yoko , Hirasaki Eishi , Fisahn Christian , Tubbs R. Shane , Kusukawa Jingo , Yamaki Koh‐Ichi
Published: March 2017

Recent studies using cone‐beam computer tomography (CBCT) have added to our understanding of anatomical variation in the mandible of humans. However, the distribution of nerves cannot be revealed by CBCT. There have been investigations of the distribution of nerves relating to the mandible, but some proposed causes of these variations remain controversial. In this study, we observed a total of 10 sides from five mandibles of Macaca fascicularis of unknown age and sex using CBCT and dissection under stereomicroscopy. Nine of the 10 sides had two mental foramina in each side. Innervation by the mental nerves depended on the locations of those foramina. The long branch to the mandibular angle ran with a branch of the facial artery, which joined the mental artery in all 10 sides. Five specimens had a median perforating canal in the mandibular bone. In addition, a branch of the sublingual artery, which joined with the small branches of the submental artery, entered the mandibular bone from the median lingual foramen. This foramen was located in the lower part of the mandibular symphysis and passed via the median perforating canal to exit from the median labial foramen, also located in the lower part of the mandibular symphysis. We speculate that the median perforating canal of the mandible, rarely found in humans, is the remnant of the feeding artery of the fetal mandible, and in M. fascicularis is seen in all specimens because they have no mental protuberance. Anat Rec, 300:1464–1471, 2017. © 2017 Wiley Periodicals, Inc.
De Novo Synthesis of Mono‐ and Oligosaccharides via Dihydropyran Intermediates
Authors: Song Wangze , Wang Shuojin , Tang Weiping
Published: March 2017

The importance of carbohydrates is evident by their essential role in all living systems. Their syntheses have attracted attention from chemists for over a century. Most chemical syntheses in this area focus on the preparation of carbohydrates from naturally occurring monosaccharides. De novo chemical synthesis of carbohydrates from feedstock starting materials has emerged as a complementary method for the preparation of diverse mono‐ and oligosaccharides. In this review, the history of de novo carbohydrate synthesis is briefly discussed and particular attention is given to methods that address the formation of glycosidic bonds for potential de novo synthesis of oligosaccharides. Almost all methods of this kind involve the formation of dihydropyran intermediates. Recent progress in forming dihydropyrans by Achmatowicz rearrangement, hetero‐Diels–Alder cycloaddition, ring‐closing metathesis, and other methods is also elaborated.
Fault Detection and Isolation Method Based on H−/H∞ Unknown Input Observer Design in Finite Frequency Domain
Authors: Zhou Meng , Wang Zhenhua , Shen Yi
Published: March 2017

This paper proposes an actuator fault detection and isolation strategy based on a bank of unknown input observers with finite frequency specifications. In order to deal with actuator fault diagnosis problem, a bank of H−/H∞ unknown input observers are designed to generate residuals, which are insensitive to the corresponding faults but sensitive to the other actuators faults, and meanwhile robust against the unknown disturbances. In this paper, the actuator faults and unknown disturbances are considered to belong to finite frequency domains, and two finite frequency performance indices are used to measure the fault sensitivity and the disturbance robustness of the residuals. Furthermore, some parameters for extra design of freedom are introduced in the H−/H∞ unknown input observers design. Based on the generalised Kalman‐Yakubovich‐Popov (GKYP) lemma, the design conditions of the H−/H∞ unknown input observer are derived and formulated as linear matrix inequalities (LMIs). Finally, a VTOL aircraft model is used to demonstrate the performance of the proposed fault diagnosis scheme.
Observer‐based Fault Estimators Using Iterative Learning Scheme for Linear Time‐delay Systems with Intermittent Faults
Authors: Feng Li , Zhang Ke , Chai Yi , Yang Zhimin , Xu Shuiqing
Published: March 2017

This paper deals with the fault estimation problem for a class of linear time‐delay systems with intermittent fault and measurement noise. Different from existing observer‐based fault estimation schemes, in the proposed design, an iterative learning observer is constructed by using the integrated errors composed of state predictive error and tracking error in the previous iteration. First of all, Lyapunov function including the information of time delay is proposed to guarantee the convergence of system output. Subsequently, a novel fault estimation law based on iterative learning scheme is presented to estimate the size and shape of various fault signals. Upon system output convergence analysis, we proposed an optimal function to select appropriate learning gain matrixes such that tracking error converges to zero, simultaneously to ensure the robustness of the proposed iterative learning observer which is influenced by measurement noise. Note that, an improved sufficient condition for the existence of such an estimator is established in terms of the linear matrix inequality (LMI) by the Schur complements and Young relation. In addition, the results are both suit for the systems with time‐varying delay and the systems with constant delay. Finally, three numerical examples are given to illustrate the effectiveness of the proposed methods and two comparability examples are provided to prove the superiority of the algorithm.
Distributed Adjacency Weight Design for Second‐order Consensus in Wireless Sensor and Actuator Networks
Authors: Chen Zhenping , Huang Yourui , Li Dequan , Tang Chaoli
Published: March 2017

The energy supply for sensors in wireless sensor and actuator networks (WSANs) is usually limited, we therefore focus on how to design the adjacency weights for achieving second‐order consensus with less communication energy consumption in a distributed way, and investigate this issue from both the viewpoints of the rate of convergence and the sparsity of the network. We also derived the conditions on the consensus control parameter and the updating period for the proposed consensus protocol to ensure the convergence. It is shown that, by removing some properly chosen links, the sparsity of the resulting network can produce a positive effect on the energy efficiency of WSANs. Finally, simulation results are presented to verify the effectiveness of the proposed algorithm.
Nuclear codon reassignments in the genomics era and mechanisms behind their evolution
Authors: Kollmar Martin , Mühlhausen Stefanie
Published: March 2017

The canonical genetic code ubiquitously translates nucleotide into peptide sequence with several alterations known in viruses, bacteria, mitochondria, plastids, and single‐celled eukaryotes. A new hypothesis to explain genetic code changes, termed tRNA loss driven codon reassignment, has been proposed recently when the polyphyly of the yeast codon reassignment events has been uncovered. According to this hypothesis, the driving force for genetic code changes are tRNA or translation termination factor loss‐of‐function mutations or loss‐of‐gene events. The free codon can subsequently be captured by all tRNAs that have an appropriately mutated anticodon and are efficiently charged. Thus, codon capture most likely happens by near‐cognate tRNAs and tRNAs whose anticodons are not part of the recognition sites of the respective aminoacyl‐tRNA‐synthetases. This hypothesis comprehensively explains the CTG codon translation as alanine in Pachysolen yeast together with the long known translation of the same codon as serine in Candida albicans and related species, and can also be applied to most other known reassignments.
Meta-analysis of prophylactic abdominal drainage in pancreatic surgery
Authors: Hüttner F J , Probst P , Knebel P , Strobel O , Hackert T , Ulrich A , Büchler M W , Diener M K
Published: March 2017

Background

Intra-abdominal drains are frequently used after pancreatic surgery whereas their benefit in other gastrointestinal operations has been questioned. The objective of this meta-analysis was to compare abdominal drainage with no drainage after pancreatic surgery.

Methods

PubMed, the Cochrane Library and Web of Science electronic databases were searched systematically to identify RCTs comparing abdominal drainage with no drainage after pancreatic surgery. Two independent reviewers critically appraised the studies and extracted data. Meta-analyses were performed using a random-effects model. Odds ratios (ORs) were calculated to aggregate dichotomous outcomes, and weighted mean differences for continuous outcomes. Summary effect measures were presented together with their 95 per cent confidence intervals.

Results

Some 711 patients from three RCTs were included. The 30-day mortality rate was 2·0 per cent in the drain group versus 3·4 per cent after no drainage (OR 0·68, 95 per cent c.i. 0·26 to 1·79; P = 0·43). The morbidity rate was 65·6 per cent in the drain group and 62·0 per cent in the no-drain group (OR 1·17, 0·86 to 1·60; P = 0·31). Clinically relevant pancreatic fistulas were seen in 11·5 per cent of patients in the drain group and 9·5 per cent in the no-drain group. Reinterventions, intra-abdominal abscesses and duration of hospital stay also showed no significant difference between the two groups.

Conclusion

Pancreatic resection with, or without abdominal drainage results in similar rates of mortality, morbidity and reintervention.
Toward A Place‐Based Understanding of Business Sustainability: The Role of Green Competitors and Green Locales in Firms' Voluntary Environmental Engagement
Authors: DeBoer Jennifer , Panwar Rajat , Rivera Jorge
Published: March 2017

Management research has extensively considered who, what, when, why, which and how aspects pertaining to firms' voluntary environmental practices, yet the where aspect, which would consider the role of a firm's location on its environmental practices, has received remarkably less attention. We explore three research questions relating social and physical attributes of a firm's location with its engagement in a voluntary environmental program (VEP). Drawing on a sample of hotels participating in a Costa Rican VEP, we find that the number of VEP certified competitors (i.e. green competitors) and firm proximity to a sacrosanct environment (i.e. a green locale) are positively related to a firm's level of VEP engagement. We also find an interaction effect such that the relationship between the number of VEP certified competitors and the level of VEP engagement is positively moderated by firm proximity to a green locale. We argue that firms' voluntary environmental engagement can be enhanced by developing green clusters amid green corridors. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Long‐term clinical outcomes of successful revascularization with drug‐eluting stents for chronic total occlusions: A systematic review and meta‐analysis
Authors: Gao Lei , Wang Yabin , Liu Yuqi , Cao Feng , Chen Yundai
Published: March 2017

Objectives

To determine whether successful percutaneous coronary intervention (PCI) using drug‐eluting stents (DESs) have beneficial effects on long‐term outcomes in patients with chronic total occlusions (CTOs) compared with failed PCIs for CTOs.

Background

Several observational studies have evaluated the long‐term clinical outcomes of successful PCIs using DESs for CTOs. However, the results of these studies were inconsistent and inconclusive. Methods: We searched five online electronic databases to identify all the publications assessing the long‐term outcomes of successful and failed PCIs using DESs for CTOs. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated by STATA software.

Results

A total of nine studies involving 5958 CTO patients who underwent successful PCI and 1511 CTO patients who underwent failed PCI were included in this meta‐analysis. The results of the analysis indicated that successful CTO PCIs using DESs were associated with lower long‐term all‐cause mortality(OR = 0.55, 95% CI = 0.45–0.67, P < 0.001), lower risk of myocardial infarction (OR = 0.45, 95% CI = 0.23–0.74, P = 0.002), lower risk of major adverse cardiac events (MACEs, OR = 0.44, 95% CI = 0.27–0.72, P = 0.001), and less incidence of subsequent coronary artery bypass grafting (OR = 0.10, 95% CI = 0.05–0.21, P < 0.001) than failed CTO PCIs. However, there was no difference in the incidence of target vessel revascularization (OR = 1.06, 95% CI = 0.17–6.60, P > 0.05) between the two groups.

Conclusion

Successful CTO PCI using DESs can reduce long‐term all‐cause mortality and the risks of MI, MACEs, and CABG in patients with CTOs. © 2017 Wiley Periodicals, Inc.
Catalytic Effect of Potassium Compounds in Soot Oxidation
Authors: Rinkenburger Alexander , Toriyama Takaaki , Yasuda Kazuhiro , Niessner Reinhard
Published: March 2017

The combustion temperatures of soot in particulate filters can be decreased to exhaust gas temperatures by using catalysts. In addition to oxidic catalysts, alkali metal salts are very effective catalysts. Although soot is one of the world's most unwanted byproducts, combustion is still not fully understood. In this study, different soot mixed internally with salt samples were produced. All salts lead to a marked, salt‐ and salt‐content‐dependent decrease of the temperature‐programmed oxidation temperatures of maximum CO + CO2 emissions (Tmax), with K2CO3 being one of the most effective catalysts that leads to a decrease of the Tmax of up to 300 °C. Structural parameters of the internally mixed soot derived by using Raman microspectroscopy, SEM, and scanning mobility particle size analysis did not change significantly; BET areas showed slight trends to lower areas with increased salt content, but no substantial correlations were observed. In contrast, a correlation of the oxidation reactivity to the number distribution of the measured actual fringe lengths by using high‐resolution transmission electron microscopy and the peak areas measured by using EPR spectroscopy was found. Salts lead to a narrowing of the actual fringe length number distributions to lower sizes and to reduced EPR peak areas. This demonstrates that the salts influence the nanostructure of the graphene planes by shortening the planes and further substantiates that soot oxidation is at least partly based on electron transfer and not only oxygen transfer. EPR spectroscopy measurements indicate that the oxidation mechanism is based on a temperature‐dependent chemical equilibrium, which depends on the K+/anion binding strength.
How Does CeIII Nitrate Dissolve in a Protic Ionic Liquid? A Combined Molecular Dynamics and EXAFS Study
Authors: Serva Alessandra , Migliorati Valentina , Spezia Riccardo , D'Angelo Paola
Published: March 2017

A diluted solution of Ce(NO3)3 in the protic ionic liquid (IL) ethylammonium nitrate (EAN) was investigated using molecular dynamics (MD) simulations and extended X‐ray absorption fine structure (EXAFS) spectroscopy. For the first time polarizable effects were included in the MD force field to describe a heavy metal ion in a protic IL, but, unlike water, they were found to be unessential. The CeIII ion first solvation shell is formed by nitrate ions arranged in an icosahedral structure, and an equilibrium between monodentate and bidentate ligands is present in the solution. By combining distance and angular distribution functions it was possible to unambiguously identify this peculiar coordination geometry around the ions dissolved in solution. The metal ions are solvated within the polar domains of the EAN nanostructure and the dissolved salt induces almost no reorganization of the pre‐existing structure of EAN upon solubilization.
Self‐Assembled Multivalent (SAMul) Polyanion Binding—Impact of Hydrophobic Modifications in the Micellar Core on DNA and Heparin Binding at the Peripheral Cationic Ligands
Authors: Albanyan Buthaina , Laurini Erik , Posocco Paola , Pricl Sabrina , Smith David K.
Published: March 2017

This paper reports a small family of cationic surfactants designed to bind polyanions such as DNA and heparin. Each molecule has the same hydrophilic cationic ligand and a hydrophobic aliphatic group with eighteen carbon atoms with one, two, or three alkene groups within the hydrophobic chain (C18‐1, C18‐2 and C18‐3). Dynamic light scattering indicates that more alkenes lead to geometric distortion, giving rise to larger self‐assembled multivalent (SAMul) nanostructures. Mallard Blue and Ethidium Bromide dye displacement assays demonstrate that heparin and DNA have markedly different binding preferences, with heparin binding most effectively to C18‐1, and DNA to C18‐3, even though the molecular structural differences of these SAMul systems are buried in the hydrophobic core. Multiscale modelling suggests that adaptive heparin maximises enthalpically favourable interactions with C18‐1, while shape‐persistent DNA forms a similar number of interactions with each ligand display, but with slightly less entropic cost for binding to C18‐3—fundamental thermodynamic differences in SAMul binding of heparin or DNA. This study therefore provides unique insight into electrostatic molecular recognition between highly charged nanoscale surfaces in biologically relevant systems.
Cyclic Bis‐porphyrin‐Based Flexible Molecular Containers: Controlling Guest Arrangements and Supramolecular Catalysis by Tuning Cavity Size
Authors: Mondal Pritam , Sarkar Sabyasachi , Rath Sankar Prasad
Published: March 2017

Three cyclic zinc(II) bis‐porphyrins (CB) with highly flexible linkers are employed as artificial molecular containers that efficiently encapsulate/coordinate various aromatic aldehydes within their cavities. Interestingly, the arrangements of guests and their reactivity inside the molecular clefts are significantly influenced by the cavity size of the cyclic containers. In the presence of polycyclic aromatic aldehydes, such as 3‐formylperylene, as a guest, the cyclic bis‐porphyrin host with a smaller cavity (CB1) forms a 1:1 sandwich complex. Upon slightly increasing the spacer length and thereby the cavity size, the cyclic host (CB2) encapsulates two molecules of 3‐formylperylene that are also stacked together due to strong π–π interactions between them and CH–π interactions with the porphyrin rings. However, in the cyclic host (CB3) with an even larger cavity, two metal centers of the bis‐porphyrin axially coordinate two molecules of 3‐formylperylene within its cavity. Different arrangements of guest inside the cyclic bis‐porphyrin hosts are investigated by using UV/Vis, ESI‐MS, and 1H NMR spectroscopy, along with X‐ray structure determination of the host–guest complexes. Moreover, strong binding of guests within the cyclic bis‐porphyrin hosts support the robust nature of the host–guest assemblies in solution. Such preferential binding of the bis‐porphyrinic cavity towards aromatic aldehydes through encapsulation/coordination has been employed successfully to catalyze the Knoevenagel condensation of a series of polycyclic aldehydes with active methylene compounds (such as Meldrum's acid and 1, 3‐dimethylbarbituric acid) under ambient conditions. Interestingly, the yields of the condensed products significantly increase upon increasing spacer lengths of the cyclic bis‐porphyrins because more substrates can then be encapsulated within the cavity. Such controllable cavity size of the cyclic containers has profound implications for constructing highly functional and modular enzyme mimics.
Structural, Photophysical, and Magnetic Circular Dichroism Studies of Three Rigidified meso‐Pentafluorophenyl‐Substituted Hexaphyrin Analogues
Authors: Ishida Masatoshi , Furuyama Taniyuki , Lim Jong Min , Lee Sangsu , Zhang Zhan , Ghosh Sudip K. , Lynch Vincent M. , Lee Chang‐Hee , Kobayashi Nagao , Kim Dongho , Sessler Jonathan L.
Published: March 2017

Detailed electronic, structural, photophysical, and redox studies of a series of meso‐pentafluorophenyl‐substituted hexaphyrins, namely amethyrin (1), rosarin (2), and rubyrin (3), are described. In prior work, it was found that the electronic states of the antiaromatic hexapyrrolic macrocycle, [24]rosarin 2, could be modified by exposure to several Brønsted acids (e.g., HCl, HBr and HI) to produce either one‐ and two‐electron reduced species, or both. In an effort to gain further insights into the reactivity of hexaphyrins possessing different π‐conjugation pathways, the β‐dodecamethyl‐substituted [24]amethyrin 1 was prepared and its electronic structure was analyzed along with that of the o‐phenylene‐bridged [26]rubyrin 3 and rosarin 2 The [4n] and [4n+2] π‐conjugated formulations of 2 and 3, respectively, were inferred from steady‐state, fs‐transient absorption and two photon absorption measurements. Similar photophysical analyses lead to the conclusion that 1 is best considered as nonaromatic or weakly antiaromatic. Magnetic circular dichroism (MCD) spectroscopic analyses of hexaphyrins 1 and 3, as well as comparisons to 2, and theoretical perimeter MO diagram analyses provided support for the electronic assignments. In contrast to what was found for 2, simple protonation of 1 and 3 by halohydric acids did not induce an evident, redox‐based change in the electronic structure of the macrocycle.
Anionic Derivatives of Perfluorinated Trimethylgold
Authors: Pérez‐Bitrián Alberto , Martínez‐Salvador Sonia , Baya Miguel , Casas José M. , Martín Antonio , Menjón Babil , Orduna Jesús
Published: March 2017

The homoleptic compound [PPh4][CF3AuCF3] cleanly undergoes photoinduced oxidative addition of CF3I to afford the organogold(III) derivative [PPh4][(CF3)3AuI] in good yield and under mild conditions. This compound provides a convenient entry to the chemistry of the perfluorinated (CF3)3Au fragment, the properties of which were analyzed with the aid of DFT methods and compared with those of the homologous non‐fluorinated (CH3)3Au moiety. It was found that reductive elimination of CX3−CX3 in the former (X=F) requires a much higher energy barrier than in the latter (X=H) and is therefore considerably less favored. This can be considered as one of the main features underlying the significantly higher stability associated to the (CF3)3Au fragment and its derivatives. This unsaturated, 14‐electron species can be stabilized by coordination of any of the halide ligands, including fluoride. In fact, the whole series of anionic [PPh4][(CF3)3AuX] complexes (X=F, Cl, Br, I, CN) has now been isolated and conveniently characterized. Evidence for intermolecular decomposition pathways upon thermolysis in the condensed phase is presented.
Cancer‐Specific, Intracellular, Reductive Activation of Anticancer PtIV Prodrugs
Authors: Reshetnikov Viktor , Daum Steffen , Mokhir Andriy
Published: March 2017

Because cellular uptake of anticancer PtII and PtIV drugs occurs by different mechanisms, the latter ones can exhibit substantial activity towards cells, which have either intrinsic or acquired resistance towards PtII drugs. However, this positive effect is diminished due to reductive activation of PtIV drugs in extracellular space that can be one of the reasons why they have not yet been approved for clinical use despite over 60 clinical trials conducted worldwide. Herein, we suggest a solution to this problem by achieving highly specific intracellular versus extracellular prodrug reduction. In particular, we prepared a hybrid PtIV prodrug containing two pro‐reductants. This hybrid was uptaken by cells, the pro‐reductants were activated in the cancer‐specific microenvironment (high H2O2), and reduced PtIV by two one‐electron transfers. The drug formed in this way induced cell death both in cisplatin‐sensitive and resistant cell lines, but remained nontoxic to normal cells.
Design, Synthesis, Biological Evaluation and SARs of Novel Anthranilic Diamides Derivatives Containing Amide, Carbamate, Urea, and Thiourea Moieties
Authors: Liu Jingbo , Li Yuxin , Zhang Xiulan , Cheng Dandan , Wei Wei , Wu Changchun , Xie Yongtao , Xiong Lixia , Li Zhengming
Published: March 2017

In order to discover potential ryanodine receptor insecticides, 21 novel anthranilic diamides analogues (C, D, E, and F) containing amide, carbamate, urea, and thiourea moieties were designed and synthesized based on bioisosteric approach. The biological assays against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella) indicated that these compounds displayed moderate to excellent activities. Especially, compound D1 showed 100% larvicidal activities against oriental armyworm at 1.0 mg•L−1, equivalent to the standard chlorantraniliprole (100%, 1.0 mg•L−1). Moreover, the larvicidal activity of D1 against diamondback moth was 100% at 0.1 mg•L−1, more effective than that of chlorantraniliprole (90%, 0.1 mg•L−1). Therefore, D1 can be used as a new lead structure for the development of insecticidal agents. The preliminary structure‐activity relationship showed that the introduction od carbamate groups into 4‐position on the benzene ring of the N‐phenylpyrazole moiety has a positive effect on the larvicidal activities.
Synthesis of β‐tubulin occurs within chromatoid body of round spermatids
Authors: Fujii Yuki , Fujita Hideaki , Yokota Sadaki
Published: March 2017

mRNAs for proteins required in elongated spermatids are considered to be transcribed at an early stage and stored in cytoplasm, presumably in chromatoid body (CB), one type of nuage component (a unique structure that appears and disappears during spermatogenesis), because transcription of genes does not occur at late stages. In elongated spermatids, a large amount of tubulin molecules is required to form microtubules of manchette and flagellum. To investigate the possible role of CB in translation of tubulin mRNA, we performed immunofluorescence and immunoelectron microscopic localization studies of α‐ and β‐tubulin in rat spermatogenic cells. β‐tubulin was detected in CB, but α‐tubulin was not. Other nuage components present in pachytene spermatocytes (ISPG, IMC, SB) were negative for both α‐ and β‐tubulin. Our findings suggest that: (i) β‐tubulin in round spermatids is translated within the CB, whereas α‐tubulin is not; (ii) αβ‐heterodimers are formed outside CB and incorporated into microtubules of manchette and flagellum.
Improving Nonspecific Binding and Solubility: Bicycloalkyl Groups and Cubanes as para‐Phenyl Bioisosteres
Authors: Auberson Yves P. , Brocklehurst Cara , Furegati Markus , Fessard Thomas C. , Koch Guido , Decker Andrea , La Vecchia Luigi , Briard Emmanuelle
Published: March 2017

Bicycloalkyl groups have been previously described as phenyl group bioisosteres. This article describes the synthesis of new building blocks allowing their introduction into complex molecules, and explores their use as a means to modify the physicochemical properties of drug candidates and improve the quality of imaging agents. In particular, the replacement of an aromatic ring with a bicyclo[1.1.1]pentane‐1,3‐diyl (BCP) group improves aqueous solubility by at least 50‐fold, and markedly decreases nonspecific binding (NSB) as measured by CHI(IAM), the chromatographic hydrophobicity index on immobilized artificial membranes. Structural variations with the bicyclo[2.2.2]octane‐1,4‐diyl group led to more lipophilic molecules and did not show the same benefits regarding NSB or solubility, whereas substitutions with cubane‐1,4‐diyl showed improvements for both parameters. These results confirm the potential advantages of both BCP and cubane motifs as bioisosteric replacements for optimizing para‐phenyl‐substituted molecules.
Nanostructured Multilayer Films Assembled from Poly(dopamine)‐Coated Carbon Nanotubes for Controlling Cell Behavior
Authors: Li Bo‐chao , Ren Ke‐feng , Zhang He , Jia Fan , Wang Jin‐lei , Chang Hao , Wang Yun‐bing , Ji Jian
Published: March 2017

Nano‐topographic surfaces have been used as an effective tool to control cell behavior such as adhesion and proliferation. In this study, multilayer films with nano‐topographic features were fabricated by alternatively assembling poly(l‐lysine) (PLL) and poly(dopamine)‐coated carbon nanotubes (CNTs@PDA) layers. The growth of PLL/CNTs@PDA film presented a perfect linear relationship with the number of bilayers. A nanostructured morphology with interpenetrating CNT networks was observed by scanning electron microscopy (SEM). Adhesion and proliferation of endothelial cells (ECs) and smooth muscle cells (SMCs) on the PLL/CNTs@PDA multilayer films have been evaluated. The films support initial adhesion of both ECs and SMCs. Interestingly, the PLL/CNTs@PDA multilayer films were found to promote proliferation of SMCs and inhibited proliferation of ECs. Further, pheochromocytoma (PC12) cells were employed to evaluate the influence of PLL/CNTs@PDA multilayer films on the outgrowth of synapses. We found that the nanostructured surface significantly promoted the synapses of PC12 cell growth and formation. Our findings suggest that cytophilic surfaces with the nanostructured morphology have diverse effects on different cells, which sheds light on new design of biomaterial surfaces in cell‐based applications.
Application of Azulene in Constructing Organic Optoelectronic Materials: New Tricks for an Old Dog
Authors: Xin Hanshen , Gao Xike
Published: March 2017

Azulene, as an isomer of naphthalene, has received increasing interest due to its unique chemical structure and unusual photophysical properties, including a large dipole moment of 1.08 D, a narrow energy gap between the HOMO and LUMO, and abnormal fluorescence (anti‐Kasha's rule) from the second excited state to the ground state. In this Minireview, the general strategies and representative synthetic methods for the preparation and functionalization of azulene and its derivatives are presented, and then the application of azulene‐based optoelectronic materials in organic field‐effect transistors and solar cells is discussed. Finally, the challenges and outlook on developing azulene‐based optoelectronic materials are discussed, together with several key points on molecular design and synthesis.
Understanding the Changes to Biomass Surface Characteristics after Ammonia and Organosolv Pretreatments by Using Time‐of‐Flight Secondary‐Ion Mass Spectrometry (TOF‐SIMS)
Authors: Tolbert Allison K. , Yoo Chang Geun , Ragauskas Arthur J.
Published: March 2017

Surface characteristic changes to poplar after ammonia and organosolv pretreatments were investigated by means of time‐of‐flight secondary‐ion mass spectrometry (TOF‐SIMS) analysis. Whereas normalized total polysaccharides and lignin contents on the surface differed from bulk chemical compositions, the surface cellulose ions detected by TOF‐SIMS showed the same value trend as the cellulose content in the biomass. In addition, the lignin syringyl/guaiacyl ratio according to TOF‐SIMS results showed the same trend as the ratio measured by means of NMR spectroscopic analysis, even though the ratio scales for each method were different. A similar correlation was determined between the surface cellulose and glucose release after enzymatic hydrolysis. These results demonstrate that surface characterization using TOF‐SIMS can provide important information about the effects of pretreatment on biomass properties and its hydrolysis.
Decarboxylative Alkynylation of Biomass‐Derived Compounds by Metal‐Free Visible Light Photocatalysis
Authors: Schwarz Johanna , König Burkhard
Published: March 2017

A mild method for decarboxylative C−C bond formation between natural carboxylic acids and alkynes is reported. Activation of a very broad scope of carboxylic acids derived from renewable resources is achieved by esterification to N‐(acyloxy)phthalimides. The cross‐coupling with acetylenic sulfones proceeds under irradiation with green light (528 nm) in the presence of the organic photocatalyst eosin Y and provides a metal‐free, environmentally friendly and inexpensive alternative to known decarboxylative alkynylations.
Integrating Eco‐Innovations and Stakeholder Engagement for Sustainable Development and a Social License to Operate
Authors: Provasnek Anna Katharina , Sentic Anton , Schmid Erwin
Published: March 2017

Eco‐innovations of corporations are seen to contribute to the mitigation of negative impacts on the natural environment. However, despite environmental gains, some eco‐innovations fail in the marketplace while others succeed. We propose a framework that reflects the connection between eco‐innovations and their social license to operate. Corporations can increase the market success of eco‐innovations if they can gain a social license to operate based on fair and trustworthy stakeholder engagement shaped by the context of their societal environment. Eco‐innovations can be transformed following management steps of an internal and external evaluation, the analysis of companies' interactional status, and conformation activities for the introduction of sustainability‐oriented innovations. We conclude that the successful transformation of eco‐innovations requires the inclusion of social factors, such as stakeholders' multiple claims, to secure a social license to operate and thereby even reduce costs by avoiding sketchy corporate social responsibility measures. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment
Eco‐Efficient Synthesis of Highly Porous CoCO3 Anodes from Supercritical CO2 for Li+ and Na+ Storage
Authors: Li Hui‐Ying , Tseng Chuan‐Ming , Yang Cheng‐Hsien , Lee Tai‐Chou , Su Ching‐Yuan , Hsieh Chien‐Te , Chang Jeng‐Kuei
Published: March 2017

An eco‐efficient synthetic route for the preparation of high‐performance carbonate anodes for Li+ and Na+ batteries is developed. With supercritical CO2 (scCO2) as the precursor, which has gas‐like diffusivity, extremely low viscosity, and near‐zero surface tension, CoCO3 particles are uniformly formed and tightly connected on graphene nanosheets (GNSs). This synthesis can be conducted at 50 °C, which is considerably lower than the temperature required for conventional preparation methods, minimizing energy consumption. The obtained CoCO3 particles (ca. 20 nm in diameter), which have a unique interpenetrating porous structure, can increase the number of electroactive sites, promote electrolyte accessibility, shorten ion diffusion length, and readily accommodate the strain generated upon charging/discharging. With a reversible capacity of 1105 mAh g−1, the proposed CoCO3/GNS anode shows an excellent rate capability, as it can deliver 745 mAh g−1 in 7.5 min. More than 98 % of the initial capacity is retained after 200 cycles. These properties are clearly superior to those of previously reported CoCO3‐based electrodes for Li+ storage, indicating the merit of our scCO2‐based synthesis, which is facile, green, and can be easily scaled up for mass production.
Ghost of invasion past: legacy effects on community disassembly following eradication of an invasive ecosystem engineer
Authors: Reynolds Pamela L. , Glanz Jess , Yang Sylvia , Hann Courtney , Couture Jessica , Grosholz Edwin
Published: March 2017

By changing ecosystem processes and altering the physical landscape, invasive ecosystem engineers can have substantial impacts on ecosystem functions and human economies and may facilitate other non‐native species. Eradication programs in terrestrial and aquatic systems aim to reverse the impacts of invasive species and return the system to its pre‐invasion conditions. Despite an extensive focus on the impacts of both native and non‐native ecosystem engineers, the consequences of removing invasive ecosystem engineers, particularly in coastal ecosystems, are largely unknown. In this study, we quantified changes in a benthic community following the eradication of the invasive ecosystem engineer, hybrid cordgrassSpartina, in San Francisco Bay, California. We used field experimental manipulations to test for persistent effects of both aboveground and belowground structural modifications of the invasive plant on the benthic community. We found significant effects of the invasive plant more than four years following eradication. Experimental modification of the above‐ vs. belowground structure of this ecosystem engineer revealed taxonomic specific effects resulting in hysteresis in the recovery of the benthic food webs. We found that these “legacy effects” resulted from two specific mechanisms: (1) delayed breakdown of belowground structures (stems, roots) and (2) persistence of other invasive species whose invasion was facilitated by the ecosystem engineer. Both of these mechanisms are likely to occur in similar systems where belowground structures breakdown more slowly or where other associated long‐lived invaders persist. Our work is among the first to quantify the slow rate of change in food web and community processes and the persistent legacy effects of an invasive ecosystem engineer in a coastal ecosystem. We suggest that this delayed transition to pre‐invasion conditions could resemble an alternate state that would be misidentified without a sufficient monitoring interval or recovery duration, with consequences for future management and restoration activity planning.
Atlantic frugivory: a plant–frugivore interaction data set for the Atlantic Forest
Authors: Bello Carolina , Galetti Mauro , Montan Denise , Pizo Marco A. , Mariguela Tatiane C. , Culot Laurence , Bufalo Felipe , Labecca Fabio , Pedrosa Felipe , Constantini Rafaela , Emer Carine , Silva Wesley R. , da Silva Fernanda R. , Ovaskainen Otso , Jordano Pedro
Published: March 2017

The data set provided here includes 8,320 frugivory interactions (records of pairwise interactions between plant and frugivore species) reported for the Atlantic Forest. The data set includes interactions between 331 vertebrate species (232 birds, 90 mammals, 5 fishes, 1 amphibian, and 3 reptiles) and 788 plant species. We also present information on traits directly related to the frugivory process (endozoochory), such as the size of fruits and seeds and the body mass and gape size of frugivores. Data were extracted from 166 published and unpublished sources spanning from 1961 to 2016. While this is probably the most comprehensive data set available for a tropical ecosystem, it is arguably taxonomically and geographically biased. The plant families better represented are Melastomataceae, Myrtaceae, Moraceae, Urticaceae, and Solanaceae. Myrsine coriacea, Alchornea glandulosa, Cecropia pachystachya, and Trema micrantha are the plant species with the most animal dispersers (83, 76, 76, and 74 species, respectively). Among the animal taxa, the highest number of interactions is reported for birds (3,883) followed by mammals (1,315). The woolly spider monkey or muriqui, Brachyteles arachnoides, and Rufous‐bellied Thrush, Turdus rufiventris, are the frugivores with the most diverse fruit diets (137 and 121 plants species, respectively). The most important general patterns that we note are that larger seeded plant species (>12 mm) are mainly eaten by terrestrial mammals (rodents, ungulates, primates, and carnivores) and that birds are the main consumers of fruits with a high concentration of lipids. Our data set is geographically biased, with most interactions recorded for the southeast Atlantic Forest.