bluuebunny/crossref_metadata_2025 huggingface dataset:
A Titanium(IV)‐Based Metal–Organic Framework Featuring Defect‐Rich Ti‐O Sheets as an Oxidative Desulfurization Catalyst
Authors: Smolders Simon , Willhammar Tom , Krajnc Andraž , Sentosun Kadir , Wharmby Michael T. , Lomachenko Kirill A. , Bals Sara , Mali Gregor , Roeffaers Maarten B. J. , De Vos Dirk E. , Bueken Bart
Published: May 2019

While titanium‐based metal–organic frameworks (MOFs) have been widely studied for their (photo)catalytic potential, only a few TiIV MOFs have been reported owing to the high reactivity of the employed titanium precursors. The synthesis of COK‐47 is now presented, the first Ti carboxylate MOF based on sheets of TiIVO6 octahedra, which can be synthesized with a range of different linkers. COK‐47 can be synthesized as an inherently defective nanoparticulate material, rendering it a highly efficient catalyst for the oxidation of thiophenes. Its structure was determined by continuous rotation electron diffraction and studied in depth by X‐ray total scattering, EXAFS, and solid‐state NMR. Furthermore, its photoactivity was investigated by electron paramagnetic resonance and demonstrated by catalytic photodegradation of rhodamine 6G.
Spectroscopic and single‐crystal X‐ray diffraction studies of enantiomeric copper(II) Schiff base one‐dimensional coordination polymers with 4‐(2‐aminoethyl)benzenesulfonamide appendage: Comprehensive biological evaluation (DNA binding, cleavage, superoxide dismutase mimetic activity, topoisomerase I inhibition and cytotoxicity)
Authors: Afsan Zeenat , Roisnel Thierry , Tabassum Sartaj , Arjmand Farukh
Published: May 2019

New chiral Cu(II)‐based one‐dimensional coordination polymers [l‐C25H27CuN3O6S] (1a) and [d‐C25H27CuN3O6S] (1b) were designed and synthesized by in situ reaction of Schiff base (o‐vanillin and l‐/d‐phenylalanine) and appended ligand 4‐(2‐aminoethyl)benzenesulfonamide incorporated with Cu(II) ion. The enantiomeric complexes 1a and 1b were fully characterized using various spectroscopic techniques and single‐crystal X‐ray diffraction studies. The enantiomeric analogues 1a and 1b crystallized in chiral monoclinic P21 space group with z = 2 exhibiting a distorted square pyramidal environment around Cu(II) metal centre coordinated to N2O3 donor atoms with apical position occupied by adjacent bridging carboxylate oxygen, resulting in one‐dimensional polymeric chain structures. Comprehensive biological studies of 1a and 1b (DNA binding, superoxide dismutase (SOD), topoisomerase I and cytotoxic activity) were performed which revealed that 1a showed better prospects as a therapeutic drug candidate as compared to 1b as quantified by their comparative DNA binding (Kb, K and Ksv values), SOD mimetic activity (IC50 values of 0.160 and 0.198, respectively) and anticancer properties.
Effect of height of flotation column on flow field
Authors: Su Wenbing , Yan Xiaokang , Wang Lijun , Zhang Haijun , Cao Yijun
Published: May 2019

Cyclonic‐static microbubble flotation column (FCSMC) is a sorting equipment for micro fine‐grained minerals. The column height is an important factor affecting the flotation efficiency, which will directly affect the flow field and separation performance. In this study, particle image velocimetry measurement on single phase of lab‐scale FCSMC with diameter D of 0.1 m was tested to verify the accuracy of the turbulent model used in computational fluid dynamics simulation. Then the FCSMC with different upper column and lower column height were simulated and analyzed. Results show that the axial velocity and tangential velocity play a major role in FCSMC. With the increasing of the upper column height, both tangential velocity and centrifugal intensity decrease, which help to get a static environment for column flotation unit. But too high upper column height will affect the separation of the cyclone flotation unit due to small centrifugal intensity. When the lower column height‐to‐diameter ratio H2/D increases from 1 to 4, it has no obvious effect on column flotation unit, but does effect on the flow field of the cyclone flotation unit. As the lower column height increases, the upward overflow is more prominent and the region becomes larger. Peculiarly, tangential velocity is large under too small lower column height, like H2/D = 1, but is bad for the separation of large size tailings due to low distance and great suction. Within the scope of this study, the lower column height range is more suitable for H2/D = 2–3.
Reinforced properties of polybenzoxazine‐based nanocomposites with siloxane benzoxazine‐modified halloysite nanotubes
Authors: Li Jing , Shen Zhiqiang , Li Huanxin , Xu Li , Song Huaijun , Guan Gang , Liu Guoji
Published: May 2019

Siloxane benzoxazine monomer (Ba‐s) was synthesized using phenol, 3‐aminopropyltriethoxysilane (KH‐550), and paraformaldehyde, and then introduced onto halloysite nanotubes (HNTs) surface as a coupling agent to obtain functionalized HNTs (mHNTs). 1, 6‐hexanediamine/phenol benzoxazine (Ba‐h) was selected as a matrix to blend with mHNTs at the mass ratios of 1:0, 9:1, 7:1, 6:1, 4:1,7:3, and 3:2, respectively. The ring‐opening copolymerization behaviors of the nanocomposites were investigated by differential scanning calorimetry. The results implied that the polymerization temperature of Ba‐h was decreased by the grafted HNTs. The results of thermogravimetric analysis and dynamic mechanical analysis displayed that the obtained copolymers exhibit different degrees of improvement in the thermal stability and mechanical properties of Ba‐h. These enhancements are attributed to the homogeneous dispersion of HNTs and the strong matrix‐nanoparticle interactions based on SEM and TEM results. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47882.
High‐density polyethylene membranes embedded with carboxylated and polyethylene glycol‐grafted nanodiamond to be used in membrane bioreactors
Authors: Kivi Masoud Azimian , Alinia Hossein , Jafarzadeh Yoones , Yegani Reza
Published: May 2019

In this work, neat and modified nanodiamond (ND) particles were embedded into high‐density polyethylene (HDPE) membranes to improve hydrophilicity and antifouling properties. The membranes were prepared via thermally induced phase separation (TIPS) method and used for pharmaceutical wastewater treatment in membrane bioreactors (MBR) system. To prevent the agglomeration of ND, it was modified using two methods: thermal carboxylation (ND‐COOH) and grafting with polyethylene glycol (ND‐PEG). Membranes with different concentration of ND‐COOH and ND‐PEG nanoparticles ranging from 0.00 to 1.00 wt % were prepared and characterized using a set of analyses including water contact angle, pure water flux, tensile strength, differential scanning calorimeter, field emission scanning electron microscopy, and energy dispersive X‐ray spectroscopy. It was found that the optimum contents of ND‐COOH and ND‐PEG nanoparticles were 0.50 wt % and 0.75 wt %, respectively. The interfacial interaction between nanoparticles and HDPE matrix was studied based on Pukanzsky model. To examine the performance of membranes, critical flux, filtration experiment in the MBR, and fouling analysis of membranes were carried out. The results showed that among the fabricated membranes, 0.75 wt % HDPE/ND‐PEG membrane had the highest water flux and the best antifouling properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47914.
Enantioselective synthesis and biological investigation of tetrahydro‐β‐carboline‐based HDAC6 inhibitors with improved solubility
Authors: Grünstein Elisabeth , Sellmer Andreas , Mahboobi Siavosh
Published: May 2019

Aberrant epigenetic changes in DNA methylation and histone modification by acetylation or deacetylation regulate the pathogenesis of many diseases. Especially selective inhibitors are getting more and more attention. We recently reported on a new class of potent and selective anti‐inflammatory and antirheumatic histone deacetylase 6 (HDAC6) inhibitors (e.g., Marbostat‐100). The attachment of a morpholinoethoxy part to the head group dramatically enhances the solubility, in particular the solubility in aqueous solutions, of the lead compound Marbostat‐100. Here, we present the enantioselective synthesis of small‐molecule compounds based on the tetrahydro‐β‐carboline core system with improved solubility, and the influence of the stereochemistry on the biological activity. The enantiomers were synthesized in good enantiomeric excess (ee) purity and were potent and selective HDAC6 inhibitors, whereas theS‐derivativeS‐21is clearly the eutomer. The potency of our selective HDAC6 inhibitors is demonstrated byKivalues in the range of 0.5–2 nM toward HDAC6, and the selectivity was proved in cellular assays by Western blot analysis taking ac‐tubulin as surrogate parameter.
Framing experts' (dis)agreements about uncertain environmental events
Authors: Løhre Erik , Sobkow Agata , Hohle Sigrid Møyner , Teigen Karl Halvor
Published: May 2019

Agreements and disagreements between expert statements influence lay people's beliefs. But few studies have examined what is perceived as a disagreement. We report six experiments where people rated agreement between pairs of probabilistic statements about environmental events, attributed to two different experts or to the same expert at two different points in time. The statements differed in frame, by focusing on complementary outcomes (45% probability that smog will have negative health effects vs. 55% probability that it will not have such effects), in probability level (45% vs. 55% probability of negative effects), or in both respects. Opposite frames strengthened disagreement when combined with different probability levels. Approximate probabilities can be “framed” in yet another way by indicating reference values they are “over” or “under”. Statements that use different directional verbal terms (over vs. under 50%) indicated greater disagreement than statements with the same directional term but different probability levels (over 50% vs. over 70%). Framing and directional terms similarly affected consistency judgments when both statements were issued by the same expert at different occasions. The effect of framing on perceived agreement was significant for medium (10 and 20 percentage points) differences between probabilities, whereas the effect of directional term was stable for numerical differences up to 40 percentage points. To emphasize agreement between different estimates, they should be framed in the same way. To accentuate disagreements or changes of opinion, opposite framings should be used.
Moisture effects on robustness of sorghum grain protein near‐infrared spectroscopy calibration
Authors: Peiris Kamaranga H. S. , Bean Scott R. , Chiluwal Anuj , Perumal Ramasamy , Jagadish S. V. Krishna
Published: May 2019

Background and objectives

A near‐infrared (NIR) spectroscopy method was developed for rapid and nondestructive evaluation of protein content of intact sorghum grains. Effect of grain sample moisture variation on the robustness of protein calibration was investigated.

Findings

An initial NIR protein calibration model with sorghum grains in 7.28%–11.57% moisture content range with coefficient of determination (R2) of 0.94 and standard error of cross‐validation (SECV) of 0.41%, predicted protein content of an external validation set of different varieties with R2 = 0.90, root‐mean‐square error of prediction (RMSEP) = 0.42% and bias = −0.02%. However, when grains with a wider range of moisture content (7.50%–17.75%) were used for validation, prediction errors increased with R2 = 0.72 RMSEP = 0.87% and bias = −0.32%. Inclusion of grains with a wider moisture range to the calibration set improved the performance of the calibration model with a R2 = 0.83, RMSEP = 0.67% with a bias of −0.04%.

Conclusions

Variation of moisture content in grains affected the performance of the NIR protein calibration model. Likewise, inclusion of moisture variation in the calibration sample set improved the robustness of the model.

Significance and novelty

In addition to the traits of interest, variation of other physical or chemical traits should also be considered for inclusion into the calibration sample set to improve the robustness of NIR calibration models. This is especially important when NIR spectroscopy methods are developed for evaluation of breeding populations as the future grain samples from numerous crosses may be substantially diverse.
Molybdenum Selenide Electrocatalysts for Electrochemical Hydrogen Evolution Reaction
Authors: Zhang Kaili , Li Yahao , Deng Shengjue , Shen Shenghui , Zhang Yan , Pan Guoxiang , Xiong Qinqin , Liu Qi , Xia Xinhui , Wang Xiuli , Tu Jiangping
Published: May 2019

Rational construction and smart modification of cost‐effective and high‐performance electrocatalysts are of great importance for the development of high‐efficiency electrochemical hydrogen evolution reaction (HER). Molybdenum selenide (MoSe2)‐based nanocomposites are considered as one of the most promising electrocatalysts for HER, owing to its superior catalytic activity, long‐term stability, and relatively low cost. In this Review, we summarize the recent progress on MoSe2‐based electrocatalysts for HER including synthesis methods, electrochemical properties and catalytic mechanisms. The mechanism of HER and influencing factors of MoSe2‐based electrocatalysts are briefly reviewed. Additionally, the benefits and the difficulties of different synthetic methods are also summarized. Furthermore, diverse modification strategies to increase electrocatalytic activity of MoSe2 are thoroughly discussed. Finally, the challenges and outlook on the advancement of MoSe2‐based electrocatalysts are presented.
A Generalized Kinetic Framework Applied to Whole‐Cell Bioelectrocatalysis in Bioflow Reactors Clarifies Performance Enhancements for Geobacter Sulfurreducens Biofilms
Authors: Zarabadi Mir Pouyan , Couture Manon , Charette Steve J. , Greener Jesse
Published: May 2019

A common kinetic framework for studies of whole‐cell catalysis is vital for understanding and optimizing bioflow reactors. In this work, we demonstrate the applicability of a flow‐adapted version of Michaelis‐Menten kinetics to an electrocatalytic bacterial biofilm. A three‐electrode microfluidic biofilm flow reactor measured increased turnover rates by as much as 50 % from a Geobacter sulfurreducens biofilm as flow rate was varied. Based on parameters from the applied kinetic framework, flow‐induced increases to turnover rate, catalytic efficiency and device reaction capacity could be linked to an increase in catalytic biomass. This study demonstrates that a standardized kinetic framework is critical for quantitative measurements of new living catalytic systems in flow reactors and for benchmarking against well‐studied catalytic systems such as enzymes.
Solution Synthesis of Porous Silicon Particles as an Anode Material for Lithium Ion Batteries
Authors: Wang Fei , Sun Lin , Zi Wenwen , Zhao Baoxun , Du Hongbin
Published: May 2019

Nanostructured silicon‐based materials with porous structures have recently been found to be impressive anode materials with high capacity and cycling performance for lithium‐ion batteries. However, the current methods of preparing porous silicon have generally been confronted with the requirement for multiple steps and complex synthesis. In the present study, porous silicon with high surface area was prepared by using a high yielding and simple reaction in which commercial magnesium powder readily reacts with HSiCl3 with the help of an amine catalyst under mild conditions. The obtained porous silicon was coated with a nitrogen‐doped carbon layer and used as the anode for lithium‐ion batteries. The porous Si‐carbon nanocomposites exhibited excellent cycling performance with a retained discharge capacity of 1300 mA h g−1 after 200 cycles at 1 A g−1 and a discharge capacity of 750 mA h g−1 at a current density of 2 A g−1 after 250 cycles. Remarkably, the Coulombic efficiency was maintained at nearly 100 % throughout the measurements.
1,4‐Dehydrogenation with a Two‐Coordinate Cyclic (Alkyl)(amino)silylene
Authors: Koike Taichi , Kosai Tomoyuki , Iwamoto Takeaki
Published: May 2019

Cyclic (alkyl)(amino)silylene (CAASi) 1 has been found to successfully dehydrogenate 1,4‐dihydroaromatic compounds containing various substituents to afford the corresponding aromatic compounds. The observed high substrate generality proves 1 to be a potential 1,4‐dehydrogenation reagent for organic compounds. For the reaction with 9,10‐dimethyl‐9,10‐dihydroanthracene, silylene 1 activated not only benzylic C−H bonds but also aromatic C−H bonds to yield a silaacenaphthene derivative, which is an unprecedented reaction of silylenes. The results of the experimental and computational study of the reaction of CAASi 1 with 9,10‐dihydroanthracene and 1,4‐cyclohexadiene are consistent with the notion that 1,4‐dehydrogenation with CAASi 1 proceeds mainly through a stepwise hydrogen‐abstraction mechanism.
Strategies for the Synthesis of Chiral Carbon‐Bridged Group IV ansa‐Metallocenes
Authors: Bau Michael A. , Wiesler Stefan , Younas Sara L. , Streuff Jan
Published: May 2019

This minireview provides a survey of the various synthetic approaches to chiral ansa‐metallocenes of Ti, Zr, and Hf containing a carbon‐based bridge. The individual strategies to install substitution patterns at either the cyclopentadienyl framework or the bridging unit are highlighted with focus on the progress made towards a direct preparation of single complex stereoisomers. The review further includes the discussion of potential problems such as the formation of undesired diastereomers, the threat of racemization of enantiopure material, and synthetic challenges originating from the synthesis, purification, and isolation of the target complexes. The review has been written with the goal in mind to facilitate the design and synthesis of new chiral ansa‐metallocene derivatives for emerging research areas in asymmetric catalysis and organometallic chemistry.
Laser‐Induced Wurtz‐Type Syntheses with a Metal‐Free Photoredox Catalytic Source of Hydrated Electrons
Authors: Kohlmann Tim , Kerzig Christoph , Goez Martin
Published: May 2019

Upon irradiation with ns laser pulses at 355 nm, 2‐aminoanthracene in SDS micelles readily produces hydrated electrons. These “super‐reductants” rapidly attack substrates such as chloro‐organics and convert them into carbon‐centred radicals through dissociative electron transfer. For a catalytic cycle, the aminoanthracene needs to be restored from its photoionization by‐product, the radical cation, by a sacrificial donor. The ascorbate monoanion can only achieve this across the micelle–water interface, but the monoanion of ascorbyl palmitate results in a fully micelle‐contained regenerative electron source. The shielding by the micelle in the latter case not only increases the life of the catalyst but also strongly suppresses the interception of the carbon‐centred radicals by the hydrogen‐donating ascorbate moiety; and in conjunction with the high local concentrations effected by the pulsed laser, termination by radical dimerization thus dominates. We have obtained a complete and consistent picture through monitoring the individual steps and the assembled system by flash photolysis on fast and slow timescales, from microseconds to minutes; and in preparative studies on a variety of substrates, we have achieved up to quantitative dimerization with a turnover on the order of 1 mmol per hour.
A Multifunctional, Charge‐Neutral, Chiral Octahedral M12L12 Cage
Authors: Boer Stephanie A. , White Keith F. , Slater Benjamin , Emerson Adrian J. , Knowles Gregory P. , Donald William A. , Thornton Aaron W. , Ladewig Bradley P. , Bell Toby D. M. , Hill Matthew R. , Chaffee Alan L. , Abrahams Brendan F. , Turner David R.
Published: May 2019

A chiral, octahedral M12L12 cage, which is charge neutral and contains an internal void of about 2000 Å3, is reported. The cage was synthesised as an enantiopure complex by virtue of amino‐acid‐based dicarboxylate ligands, which assemble around copper paddlewheels at the vertices of the octahedron. The cage persists in solution with retention of the fluorescence properties of the parent acid. The solid‐state structure contains large pores both within and between the cages, and displays permanent porosity for the sorption of gases with retention of crystallinity. Initial tests show some enantioselectivity of the cage towards guests in solution.
The clinical outcomes of patients who developed typical atrial flutter on class 1C anti arrhythmic medications treated with hybrid approach
Authors: Grossman Lior , Katz Moshe , Beinart Roy , Nof Eyal
Published: May 2019

Introduction

A common approach to patients, who developed atrial flutter secondary to treatment with class 1C anti‐arrhythmic drugs for atrial fibrillation (AF) (1C flutter), is a hybrid approach: ablation of the Cavo‐Tricuspid isthmus (CTI) and continuation 1C medical treatment to prevent recurrence of AF. We aim to explore the clinical outcome of patients treated in this approach.

Methods and Results

Two hundred and four consecutive patients who underwent ablation for typical AFL at a tertiary medical center between 2010 and 2016 were enrolled and followed up. The clinical outcome of patient treated by the hybrid approach (treatment group; n = 67) was compared to patient without history of AF (control group; n = 137). The primary endpoint was time to occurrence of AF. Twenty‐eight (41.8%) patients in treatment group had AF occurrence in 1 year, including 9 (13.4%) patients who needed to escalate anti‐arrhythmic drug treatment to class III, and 11 (16.4%) patients who underwent AF ablation. In comparison, only 21 (15.3%) patients in control group had occurrence during the first year after ablation. The median time from ablations till AF occur was 106 ± 481 days in treatment group, and 403 ± 668 days in control group (P < .01).

Conclusions

There is a relatively high rate of AF recurrence in patients treated with the hybrid approach during the first year after CTI ablation. An alternative approach should be considered in this selected population.
Visible‐Light‐Driven Plasmonic Photocatalysis Enhanced by Charge Accumulation
Authors: Kao Kun‐Che , Nishi Hiroyasu , Tatsuma Tetsu
Published: May 2019

Plasmon‐induced charge separation (PICS) at the interface between a plasmonic material and semiconductor is employed to drive photocatalytic reactions for conversion and storage of solar energy. Most of the conventional photoelectrodes based on PICS have an n‐M type structure with an interface between n‐type semiconductor (typically TiO2) and plasmonic metal (typically Au) nanoparticles. Here we develop n‐M‐p type photoelectrodes by coating the TiO2/Au photoelectrode with Ni(OH)2 or CrOx, which can collect and store positive charges. Both of the photoelectrodes show efficient PICS under visible light and accumulate positive charges released from resonant Au nanoparticles. The accumulated charges can be used for oxidation of organic species such as ethanol in the dark. The TiO2/AuNP/Ni(OH)2 photoelectrode exhibits an oxygen evolution ability under visible light with a certain bias voltage.
Rendering differential performance preference through intelligent network edge in cloud data centers
Authors: Shen Dian , Zhou Pengcheng , Gao Yidan , Guo Xiaolin , Xiong Runqun
Published: May 2019

Sharing the network infrastructure, the performance of emerging distributed applications and services in data centers is directly impacted by the network. As these applications are becoming more and more demanding, it is challenging to satisfy their requirements of low latency, high throughput, and low packet loss rate simultaneously. Prior approaches typically resort to flow control or scheduling mechanisms, prioritizing flows according to their demands. However, none of the methods can solely satisfy the various demands of data center applications. Addressing this challenge, we propose tasch, a preference aware flow scheduling mechanism equipped in the software network edge (ie, end‐host networking). This mechanism utilizes multiple separate queues for flows with different preferences, which guarantees low packet delay for latency‐sensitive flows and provides bandwidth guarantees for throughput‐sensitive flows. A coordinating algorithm is presented to share the network resource among multiple queues with pareto‐optimality. tasch is implemented as a thin and plugable kernel module in Linux based hypervisors, which lies between the complicated physical network and tenants VMs. Subsequently, based on the flow traces of real‐world applications, extensive experiments were conducted to verify the effectiveness of network management mechanism.
Tracking Conformational Changes in Calmodulin in vitro, in Cell Extract, and in Cells by Electron Paramagnetic Resonance Distance Measurements
Authors: Dalaloyan Arina , Martorana Andrea , Barak Yoav , Gataulin Diana , Reuveny Eitan , Howe Andrew , Elbaum Michael , Albeck Shira , Unger Tamar , Frydman Veronica , Abdelkader Elwy H. , Otting Gottfried , Goldfarb Daniella
Published: May 2019

It is an open question whether the conformations of proteins sampled in dilute solutions are the same as in the cellular environment. Here we address this question by double electron‐electron resonance (DEER) distance measurements with Gd(III) spin labels to probe the conformations of calmodulin (CaM) in vitro, in cell extract, and in human HeLa cells. Using the CaM mutants N53C/T110C and T34C/T117C labeled with maleimide‐DOTA‐Gd(III) in the N‐ and C‐terminal domains, we observed broad and varied interdomain distance distributions. The in vitro distance distributions of apo‐CaM and holo‐CaM in the presence and absence of the IQ target peptide can be described by combinations of closed, open, and collapsed conformations. In cell extract, apo‐ and holo‐CaM bind to target proteins in a similar way as apo‐ and holo‐CaM bind to IQ peptide in vitro. In HeLa cells, however, in the presence or absence of elevated in‐cell Ca2+ levels CaM unexpectedly produced more open conformations and very broad distance distributions indicative of many different interactions with in‐cell components. These results show‐case the importance of in‐cell analyses of protein structures.
Controlling the Uptake of Diarylethene‐Based Cell‐Penetrating Peptides into Cells Using Light
Authors: Schober Tim , Wehl Ilona , Afonin Sergii , Babii Oleg , Iampolska Anna , Schepers Ute , Komarov Igor V. , Ulrich Anne S.
Published: May 2019

We report on diarylethene (DAE)‐containing photoswitchable cell‐penetrating peptides (CPPs) capable of photocontrolled cell entry. We demonstrate in vitro that reversible photoisomerization of a DAE fragment in the backbones of non‐cytotoxic cyclic peptides influences their binding to cell membranes and subsequent CPP‐mediated cargo internalization. Benign red light can be used to activate cell entry of our compounds. We suggest that the observed differences in cell uptake of the two photoisomers are due to changes in the molecular flexibility achieved upon DAE photoisomerization.
Effects of Polar Substituents and Media on the Performance of N,N′‐Di‐tert‐Butoxycarbonyl‐Indigos as Photoswitches
Authors: Koeppe Benjamin , Schröder Vincent R. F.
Published: May 2019

The N,N′‐di‐tert‐butoxycarbonylindigo parent compound and four symmetrically substituted derivatives alternatively containing methoxy and nitro substituents in positions 5 and 6 were synthesized. The photochromic behavior was studied in solvents ranging in polarity from toluene to acetonitrile/water mixtures and characterized in terms of trans and cis isomer spectra, conversion quantum yields and thermal half‐lives of the metastable cis isomers. The half‐lives at 21 °C varied from a few seconds (5‐nitro in polar solvents) to several days (6‐methoxy in apolar media) and can be described by the substituents’ Hammett constants. Spectroscopic and photochemical parameters, in contrast, are governed largely by the substituents’ resonance effects according to a scheme well known from thioindigos and these are termed here favorable and unfavorable resonance effects (FRE and URE, respectively). The title photoswitches show little propensity to quenching by protons and may be operated in aqueous media.
Cyclometalated Platinum(II) Complexes with Mesoionic Dibenzofuranyl‐1,2,3‐triazol‐4‐ylidene Ligands: Synthesis, Characterization and Photophysical Properties
Authors: Soellner Johannes , Strassner Thomas
Published: May 2019

Platinum(II) complexes with mesoionic
*‐cyclometalating 1,2,3‐triazolylidene ligands are highly efficient phosphorescent emitters. Herein we report a series of this type bearing dibenzofuranyl‐substituted carbenes along with different β‐diketonate auxiliary ligands. They show luminescence in the green region of the visible spectrum and quantum yields of up to 78 % at room temperature. The proposed molecular structures were verified by NMR spectroscopy and X‐ray diffraction experiments which prove the formation of the mesoionic carbene. Additionally, DFT calculations and cyclic voltammetry measurements were used to rationalize the observed photophysical properties of the reported complexes.
Acute Metabolic Switch Assay Using Glucose/Galactose Medium in HepaRG Cells to Detect Mitochondrial Toxicity
Authors: Kamalian Laleh , Douglas Oisin , Jolly Carol E. , Snoeys Jan , Simic Damir , Monshouwer Mario , Williams Dominic P. , Park B. Kevin , Chadwick Amy E.
Published: May 2019

Using galactose instead of glucose in the culture medium of hepatoma cell lines, such as HepG2 cells, has been utilized for a decade to unmask the mitochondrial liability of chemical compounds. A modified glucose‐galactose assay on HepG2 cells, reducing the experimental period for screening of mitochondrial toxicity to 2 to 4 hr, has been previously reported. HepaRG cells are one of the few cell lines that retain some of the important characteristics of human hepatocytes, offering advantages of working with a cell line, therefore, are considered an alternative for HepG2 cells in drug toxicity screening. A method is described here using HepaRG cells in an acute metabolic switch assay utilizing specific glucose/galactose media, a combined ATP‐protein‐LDH assay measuring three endpoints from one 96‐well plate, and a criteria to label a compound as a mitochondrial toxin. © 2019 by John Wiley & Sons, Inc.
A Reliable Preclinical Model to Study the Impact of Cigarette Smoke in Development and Disease
Authors: Aedo Geraldine , Miranda Miguel , Chávez Myra N. , Allende Miguel L. , Egaña José T.
Published: May 2019

The World Health Organization has estimated that, worldwide, cigarette smoking has caused more than 100 million deaths in the last century, a number that is expected to increase in the future. Understanding cigarette smoke toxicity is key for research and development of proper public health policies. The current challenge is to establish a reliable preclinical model to evaluate the effects of cigarette smoke. In this work, we describe a simple method that allows for quantifying the toxic effects of cigarette smoke using zebrafish. Here, viability of larvae and adult fish, as well as the effects of cigarette smoke extracts on vascular development and tissue regeneration, can be easily assayed. © 2019 by John Wiley & Sons, Inc.
Self‐assessment of eating disorder recovery: Absence of eating disorder psychopathology is not essential
Authors: Slof‐Op 't Landt Margarita C.T. , Dingemans Alexandra E. , de la Torre Y Rivas Jésus , van Furth Eric F.
Published: May 2019

Objective

The definition of recovery in eating disorders (EDs) according to researchers is not necessarily similar to the patient definition. This study aimed to explore the concept of recovery as assessed by those affected by an ED themselves.

Method

Participants from the Netherlands Eating disorder Registry (NER) who reported an (former) ED diagnosis (n = 814) assessed their own recovery level: current ED, partial or full recovery. Furthermore, research‐based criteria (Bardone‐Cone et al., Behaviour Research and Therapy, 2010, 48, 194–202) were applied to define recovery. Within the self‐assessed full recovery group (n = 179), participants who also fulfilled the research‐based criteria were compared to those who were only recovered based on self‐assessment in the following domains: ED psychopathology, psychiatric comorbidity, quality of life, and social and societal participation.

Results

Ninety‐six of the participants (54%) who considered themselves recovered did not fulfill the research‐based definition. The two recovery groups did not significantly differ in psychiatric comorbidity, quality of life, and social and societal participation.

Discussion

Absence of ED characteristics was not essential for individuals to consider themselves recovered. Although the self‐assessed recovery status may be subjective, it does advocate the use of additional health indicators besides ED psychopathology when defining recovery.
Insect and plant traits drive local and landscape effects on herbivory in grassland fragments
Authors: Rossetti Maria Rosa , Rösch Verena , Videla Martín , Tscharntke Teja , Batáry Péter
Published: May 2019

Herbivory is one of the most important antagonistic insect–plant interactions and can be influenced by factors at local and landscape scales. Landscape fragmentation may reduce herbivory directly (i.e., decreasing abundance and species richness of herbivores), but also indirectly increase herbivory (i.e., releasing herbivores from top‐down control). At a local scale, reduced plant diversity may enhance herbivory through lessened associated resistance, while resource availability (i.e., higher vegetation height and cover) may promote herbivory. Few studies have simultaneously considered the influence of local and landscape variables on insect herbivory. We evaluate effects of landscape (fragment size, connectivity, and arable land percentage) and local factors (plant cover and height and plant species richness) on insect herbivory in fragmented calcareous grasslands. Further, we ask whether these effects depend on feeding traits of herbivores (chewers vs. suckers) and habitat specialization of plants (specialists vs. generalists). Results show that herbivory was best explained by models including variables at both local and landscape scales. However, local factors were more important than landscape variables. Herbivory was in all cases positively related to height of herbs (i.e., taller and more heterogeneous food resources), whereas the effect of plant species richness varied with feeding traits of herbivores. Herbivory by chewers, which are commonly more generalist feeders, was negatively affected by plant species richness, supporting the idea of associated plant resistance. In contrast, herbivory by suckers, which tend to be more specialized, increased with plant richness. Although there was little influence of landscape scale, herbivory on specialist plants was significantly higher in smaller grasslands probably as a consequence of herbivore release from natural enemies. Functional redundancy among herbivore species would allow to maintain overall herbivory in fragmented calcareous grasslands. This study highlights the need to consider different herbivore and plant traits for a better understanding of herbivory responses to local and landscape factors.
Intravenous immunoglobulin (IVIg) or IVIg‐treated macrophages reduce DSS‐induced colitis by inducing macrophage IL‐10 production
Authors: Kozicky Lisa K. , Menzies Susan C. , Hotte Naomi , Madsen Karen L. , Sly Laura M.
Published: May 2019

Intravenous immunoglobulin (IVIg) is used to treat immune‐mediated diseases but its mechanism of action is poorly understood. We have reported that co‐treatment with IVIg and lipopolysaccharide activates macrophages to produce large amounts of anti‐inflammatory IL‐10 in vitro. Thus, we asked whether IVIg‐treated macrophages or IVIg could reduce intestinal inflammation in mice during dextran sulfate sodium (DSS)‐induced colitis by inducing macrophage IL‐10 production in vivo. Adoptive transfer of IVIg‐treated macrophages reduces intestinal inflammation in mice and collagen accumulation post‐DSS. IVIg treatment also reduces DSS‐induced intestinal inflammation and its activity is dependent on the Fc portion of the antibody. Ex vivo, IVIg induces IL‐10 production and reduces IL‐12/23p40 and IL‐1β production in colon explant cultures. Co‐staining tissues for mRNA, we demonstrate that macrophages are the source of IL‐10 in IVIg‐treated mice; and using IL‐10‐GFP reporter mice, we demonstrate that IVIg induces IL‐10 production by intestinal macrophages. Finally, IVIg‐mediated protection is lost in mice deficient in macrophage IL‐10 production (LysMcre+/−IL‐10fl/fl mice). Together, our data demonstrate a novel, in vivo mechanism of action for IVIg. IVIg‐treated macrophages or IVIg could be used to treat people with intestinal inflammation and may be particularly useful for people with inflammatory bowel disease, who are refractory to therapy.
Synthetic and Structural Investigations on the System Na1–xEux[Li3‐2xSi1‐xAl3xO4‐4xN4x]
Authors: Dutzler Daniel , Seibald Markus , Baumann Dominik , Ruegenberg Freia , Huppertz Hubert
Published: May 2019

During the investigation of a solid‐solution series between the alkali lithosilicate Na[Li3SiO4] and the hypothetical nitridolithoaluminate Eu[LiAl3N4] with the generalized sum formula Na1–xEux[Li3–2xSi1‐xAl3xO4–4xN4x], a hitherto unknown oxo‐nitride has been synthesized. The new material with the composition Na1–xEux[Li3–2xSi1‐xAl3xO4–4xN4x] (x = 0.22) crystallizes in the tetragonal space group I4/m (no. 87) with a = 7.704(2) and c = 3.1584(6) Å. To the best of our knowledge this is the first synthesis of a litho‐alumo‐oxo‐nitridosilicate containing either alkali‐, or rare‐earth metals. Upon excitation of this novel compound with near UV to blue light, a broadband amber emission with a maximum at 612 nm and a full width at half maximum of 2835 cm‐1 (≈ 105 nm) is observed. Furthermore, single‐crystals of the solid‐solution series could be synthesized on the oxygen‐rich side between 0 < x < 0.2. The thereby received phosphors crystallize in the Na[Li3SiO4]‐structure type and their emission maxima can be shifted in the spectral range from 469 nm up to 588 nm.
Effective Synthesis and Modification of α‐Cyclodextrin‐Based [3]Rotaxanes Enabling Versatile Molecular Design
Authors: Akae Yosuke , Sogawa Hiromitsu , Takata Toshikazu
Published: May 2019

One‐pot synthesis of various α‐cyclodextrin‐(α‐CD‐) based [3]rotaxanes in water and their structural modifications are discussed in detail. Pseudo[3]rotaxane was prepared from α‐CD and α,ω‐diaminododecane in water (above 100 g, quantitative yield in a 1 L flask). Successive urea‐forming end‐capping reactions with isocyanate in water selectively afforded [3]rotaxane with head‐to‐head structured α‐CDs. The yields were varied by bulkiness and functionality of end‐capping agents. Significant modifications of the axle end and wheel OH group of the [3]rotaxanes were performed by the Suzuki coupling with arylboronic acids and by the perfect acylation with acid anhydrides, respectively.
Heterocycle Synthesis through Pd‐Catalyzed Carbonylative Coupling
Authors: Perrone Serena , Troisi Luigino , Salomone Antonio
Published: May 2019

Heterocyclic chemistry is one of the most important and attractive areas of organic chemistry. It involves the preparation of compounds endowed with very high structural diversity and plays a central role in a multitude of highly developed areas: fine chemicals, drugs, flavors, dyes, engineered materials, and many other kinds of products contain at least one heterocyclic ring in their molecular structure. Therefore, the discovery of new methods for heterocycle synthesis is a significant objective of modern organic chemists, especially if prepared in environmentally benign and synthetically efficient ways. In this context, this minireview focuses on the synergy of two green strategies, namely multicomponent reactions and palladium‐catalyzed carbonylations, for the construction of a wide variety of heterocyclic systems. These processes are of considerable interest because they combine synthetic efficiency with respect for the environment.
A Simple and Efficient Flow Preparation of Pyocyanin a Virulence Factor of Pseudomonas aeruginosa
Authors: Mortzfeld Frederik B. , Pietruszka Jörg , Baxendale Ian R.
Published: May 2019

The synthesis of the naturally occurring toxin pyocyanin has been realized in a short 4 step sequence. The key photochemical reaction and isolation of the final product have been facilitated by the use of flow chemistry techniques and immobilised reagents. Using these procedures gram quantities of pyocyanin were easily prepared in high yield and purity.
A roadmap to integrate astrocytes into Systems Neuroscience
Authors: Kastanenka Ksenia V. , Moreno‐Bote Rubén , De Pittà Maurizio , Perea Gertrudis , Eraso‐Pichot Abel , Masgrau Roser , Poskanzer Kira E. , Galea Elena
Published: May 2019

Systems neuroscience is still mainly a neuronal field, despite the plethora of evidence supporting the fact that astrocytes modulate local neural circuits, networks, and complex behaviors. In this article, we sought to identify which types of studies are necessary to establish whether astrocytes, beyond their well‐documented homeostatic and metabolic functions, perform computations implementing mathematical algorithms that sub‐serve coding and higher‐brain functions. First, we reviewed Systems‐like studies that include astrocytes in order to identify computational operations that these cells may perform, using Ca2+ transients as their encoding language. The analysis suggests that astrocytes may carry out canonical computations in a time scale of subseconds to seconds in sensory processing, neuromodulation, brain state, memory formation, fear, and complex homeostatic reflexes. Next, we propose a list of actions to gain insight into the outstanding question of which variables are encoded by such computations. The application of statistical analyses based on machine learning, such as dimensionality reduction and decoding in the context of complex behaviors, combined with connectomics of astrocyte–neuronal circuits, is, in our view, fundamental undertakings. We also discuss technical and analytical approaches to study neuronal and astrocytic populations simultaneously, and the inclusion of astrocytes in advanced modeling of neural circuits, as well as in theories currently under exploration such as predictive coding and energy‐efficient coding. Clarifying the relationship between astrocytic Ca2+ and brain coding may represent a leap forward toward novel approaches in the study of astrocytes in health and disease.
Microglia roles in synaptic plasticity and myelination in homeostatic conditions and neurodevelopmental disorders
Authors: Bar Ela , Barak Boaz
Published: May 2019

Microglia are the immune cells of the brain, involved in synapse formation, circuit sculpting, myelination, plasticity, and cognition. Being active players during early development as well as in adulthood, microglia affect other cells directly by their long processes and unique receptors and indirectly by secreting growth factors and cytokines. In this review, we discuss the roles of microglia in neurodevelopmental disorders, synaptic plasticity, myelination, and homeostatic conditions throughout human and mouse development. Within these processes, we specifically focus on the contribution of altered microglial interactions with neurons and oligodendrocytes, altered cytokine and growth factor activities, and alterations in the complement system. We conclude by highlighting future perspectives and providing an overview of future research on microglia.
Size at birth and cognitive ability in late life: A systematic review
Authors: Krishna Murali , Jones Steven , Maden Michelle , DU Bharath , MC Ramya , Kumaran Kalyanaraman , Karat Samuel Christraprasad , Fall Caroline H.D.
Published: May 2019

Introduction

Recent evidence suggests that growth restriction in utero may lead to neurocognitive disorders in late life, either through impaired brain development or adverse metabolic programming.

Methods

Systematic review of literature investigating the relationship between size at birth and cognitive abilities in late life. The search, data extraction, and rating for the quality of reporting were conducted independently by two researchers.

Results

Of 533 selected studies, 11 were included in this systematic review and 10 of these were from high‐income setting. Of these 11 studies, eight indicated that lower birth weight is a risk factor for lower cognitive function in late life, at least in high‐income countries. The reported effect sizes were small and it was not possible to conduct meta‐analyses because of clinical heterogeneity

Discussion

A modest association of lower birth weight with lower cognitive abilities in late life is consistent with persisting effects of the prenatal environment on brain function. As with all observational studies, confounding is an alternative explanation. Further studies are required to elucidate the mechanisms.
Associations of gestational age and birth anthropometric indicators with brain white matter maturation in full‐term neonates
Authors: Jin Chao , Li Yanyan , Li Xianjun , Liu Congcong , Wang Miaomiao , Cheng Yannan , Zheng Jie , Yang Jian
Published: May 2019

Newborn assessments, including gestational age (GA) and anthropometric measurements (birth weight, crown‐heel length, head circumference) are routinely performed in pediatric settings, being used as important indicators in assessing neonatal development. Close associations of these birth indicators with later cognitive abilities were also reported. However, specific associations of these indicators with white matter (WM) development during the neonatal period remain unclear, as well as the extent to which they influence WM maturation. To address this issue, 51 full‐term neonates (GA range, 37–42 weeks) with no abnormalities on MRI were retrospectively recruited. Specific correlations between birth indicators and WM maturation, quantified by diffusion tensor imaging (DTI)‐metrics (fractional anisotropy, mean diffusivity, axial diffusivity, radial diffusivity), were identified by using DTI tract‐based spatial statistics and automated fiber‐tract quantification. Our findings suggest that (a) higher GA, birth weight, and crown‐heel length may indicate greater WM maturation in full‐term neonates, while head circumference presented weak correlation with WM maturation during early newborn period; (b) among the four indicators examined, GA was the one most associated with WM maturation. We believe that this study advances our knowledge of specific correlations between birth indicators and neonatal brain development and provides a valuable reference for future neonatal studies.
Affordable and low‐maintenance obstetric devices
Authors: Ayres‐de‐Campos Diogo , Stones William , Theron Gerhard ,   the FIGO Safe Motherhood and Newborn Health Commitee
Published: May 2019

Objective

Adequate obstetric care requires the availability of essential diagnostic and management equipment; however, for centers with budget restrictions, the acquisition and maintenance of these devices can pose major challenges. The purpose of the present paper is to disseminate knowledge about the availability of affordable and low‐maintenance obstetric devices, which might help to save lives in low‐ and medium‐resource countries.

Method

Over the course of 2015–2018, the International Federation of Gynecology and Obstetrics (FIGO) Safe Motherhood and Newborn Health Committee acquired information from different clinical and commercial sources regarding the availability of affordable and low‐maintenance essential obstetric devices.

Results

The Committee identified several devices that met the criteria of low cost and ease of maintenance: a winding handheld Doppler device for intermittent auscultation; a portable continuous fetal heart rate monitor; a validated semi‐automated blood pressure monitor; the Foley catheter balloon for labor induction in women with an unfavorable cervix; reusable metal and plastic vacuum cups and manual pumps; an intrauterine tamponade balloon; and the non‐pneumatic anti‐shock garment.

Conclusion

Several affordable and low‐maintenance obstetric devices are currently available that offer the potential to save lives in resource‐constrained settings.