bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the binding properties and structural stability of an opsin in the chytridSpizellomyces punctatususing comparative and molecular modeling
Authors: Ahrendt Steven R. , Medina Edgar Mauricio , Chang Chia-en A. , Stajich Jason E.
Published: April 2017

Background

Opsin proteins are seven transmembrane receptor proteins which detect light. Opsins can be classified into two types and share little sequence identity: type 1, typically found in bacteria, and type 2, primarily characterized in metazoa. The type 2 opsins (Rhodopsins) are a subfamily of G-protein coupled receptors (GPCRs), a large and diverse class of seven transmembrane proteins and are generally restricted to metazoan lineages. Fungi use light receptors including opsins to sense the environment and transduce signals for developmental or metabolic changes. Opsins characterized in the Dikarya (Ascomycetes and Basidiomycetes) are of the type 1 bacteriorhodopsin family but the early diverging fungal lineages have not been as well surveyed. We identified by sequence similarity a rhodopsin-like GPCR in genomes of early diverging chytrids and examined the structural characteristics of this protein to assess its likelihood to be homologous to animal rhodopsins and bind similar chromophores.

Methods

We used template-based structure modeling, automated ligand docking, and molecular modeling to assess the structural and binding properties of an identified opsin-like protein found inSpizellomyces punctatus, a unicellular, flagellated species belonging to Chytridiomycota, one of the earliest diverging fungal lineages. We tested if the sequence and inferred structure were consistent with a solved crystal structure of a type 2 rhodopsin from the squidTodarodes pacificus.

Results

Our results indicate that theSpizellomycesopsin has structural characteristics consistent with functional animal type 2 rhodopsins and is capable of maintaining a stable structure when associated with the retinaldehyde chromophore, specifically the 9-cis-retinal isomer. Together, these results support further the homology ofSpizellomycesopsins to animal type 2 rhodopsins.

Discussion

This represents the first test of structure/function relationship of a type 2 rhodopsin identified in early branching fungal lineages, and provides a foundation for future work exploring pathways and components of photoreception in early fungi.
Agerinia marandati sp. nov., a new early Eocene primate from the Iberian Peninsula, sheds new light on the evolution of the genus Agerinia
Authors: Femenias-Gual Joan , Minwer-Barakat Raef , Marigó Judit , Poyatos-Moré Miquel , Moyà-Solà Salvador
Published: April 2017

Background

The Eocene was the warmest epoch of the Cenozoic and recorded the appearance of several orders of modern mammals, including the first occurrence of Euprimates. During the Eocene, Euprimates were mainly represented by two groups, adapiforms and omomyiforms, which reached great abundance and diversity in the Northern Hemisphere. Despite this relative abundance, the record of early Eocene primates from the European continent is still scarce and poorly known, preventing the observation of clear morphological trends in the evolution of the group and the establishment of phylogenetic relationships among different lineages. However, knowledge about the early Eocene primates from the Iberian Peninsula has been recently increased through the description of new material of the genus Agerinia from several fossil sites from Northeastern Spain.

Methods

Here we present the first detailed study of the euprimate material from the locality of Masia de l’Hereuet (early Eocene, NE Spain). The described remains consist of one fragment of mandible and 15 isolated teeth. This work provides detailed descriptions, accurate measurements, high-resolution figures and thorough comparisons with other species of Agerinia as well with other Eurasian notharctids. Furthermore, the position of the different species of Agerinia has been tested with two phylogenetic analyses.

Results

The new material from Masia de l’Hereuet shows several traits that were previously unknown for the genus Agerinia, such as the morphology of the upper and lower fourth deciduous premolars and the P2, and the unfused mandible. Moreover, this material clearly differs from the other described species of Agerinia, A. roselli and A. smithorum, thus allowing the erection of the new species Agerinia marandati. The phylogenetic analyses place the three species of Agerinia in a single clade, in which A. smithorum is the most primitive species of this genus.

Discussion

The morphology of the upper molars reinforces the distinction of Agerinia from other notharctids like Periconodon. The analysis of the three described species of the genus, A. smithorum, A. marandati and A. roselli, reveals a progressive change in several morphological traits such as the number of roots and the position of the P1 and P2, the molarization of the P4, the reduction of the paraconid on the lower molars and the displacement of the mental foramina. These gradual modifications allow for the interpretation that these three species, described from the early Eocene of the Iberian Peninsula, are part of a single evolutionary lineage. The stratigraphical position of Masia de l’Hereuet and Casa Retjo-1 (type locality of A. smithorum) and the phylogenetic analyses developed in this work support this hypothesis.
Pitfalls associated with evaluating enzymatic quorum quenching activity: the case of MomL and its effect onPseudomonas aeruginosaandAcinetobacter baumanniibiofilms
Authors: Zhang Yunhui , Brackman Gilles , Coenye Tom
Published: April 2017

Background

The enzymatic degradation of quorums sensing (QS) molecules (called quorum quenching, QQ) has been considered as a promising anti-virulence therapy to treat biofilm-related infections and combat antibiotic resistance. The recently-discovered QQ enzyme MomL has been reported to efficiently degrade differentN-acyl homoserine lactones (AHLs) of various Gram-negative pathogens. Here we investigated the effect of MomL on biofilms formed by two important nosocomial pathogens,Pseudomonas aeruginosaandAcinetobacter baumannii.

Methods

MomL was expressed inE.coliBL21 and purified. The activity of MomL on AHLs with hydroxyl substituent was tested. Biofilms ofP. aeruginosaPAO1 andAcinetobacterstrains were formed in 96-well microtiter plates. Biofilm formation was evaluated by crystal violet staining, plating and fluorescence microscopy. The effect of MomL on biofilm susceptibility to antibiotics was also tested. We further evaluated MomL in dual-species biofilms formed byP. aeruginosaandA. baumannii, and in biofilms formed in a wound model. The effect of MomL on virulence ofA. baumanniiwas also tested in theCaenorhabditis elegansmodel.

Results

MomL reduced biofilm formation and increased biofilm susceptibility to different antibiotics in biofilms ofP. aeruginosaPAO1 andA. baumanniiLMG 10531 formed in microtiter platesin vitro. However, no significant differences were detected in the dual-species biofilm and in wound model biofilms. In addition, MomL did not affect virulence ofA. baumanniiin theC. elegansmodel. Finally, the effect of MomL on biofilm ofAcinetobacterstrains seems to be strain-dependent.

Discussion

Our results indicate that although MomL showed a promising anti-biofilm effect againstP. aeruginosaandA. baumaniibiofilms formed in microtiter plates, the effect on biofilm formation under conditions more likely to mimic the real-life situation was much less pronounced or even absent. Our data indicate that in order to obtain a better picture of potential applicability of QQ enzymes for the treatment of biofilm-related infections, more elaborate model systems need to be used.
Real-Time Needs, Real-Time Care: Creating Adaptive Systems of Community-Based Care for Emerging Adults
Authors: Sukhera Javeed , Lynch Jill , Wardrop Nancy , Miller Kristina
Published: April 2017

Research indicates a decline in mental health service utilization between the ages of 16 to 25, leaving emerging adults with mental illness at risk for worsening outcomes. The authors utilized a community-based participatory research (CBPR) approach to explore the mental health landscape for youth aged 16–25 in London, Canada. Interviews and focus groups (n = 30) with community and hospital system leaders, youth and caregivers were transcribed and coded using an approach informed by constructivist grounded theory. There was consensus regarding difficulties in the current system including wait times and crisis-driven services leading to powerlessness among youth and caregivers. Solutions include delivery of services through a flexible, real-time system that emphasizes patient and caregiver engagement, youth centric services and recovery-oriented care across the hospital/community continuum. The results highlight that disparate stakeholders agree regarding the need for transformational change shifting away from traditional medical models.
The transient topside layer and associated current sheet in the ionosphere of Mars
Authors: Kopf Andrew J. , Gurnett Donald A. , DiBraccio Gina A. , Morgan David D. , Halekas Jasper S.
Published: April 2017

Radar soundings from the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on board the Mars Express spacecraft have shown that transient layers exist in the dayside upper ionosphere of Mars. The most prominent of these features is a second layer at an altitude near 200 km, well above that of the main photoionization layer. While the general properties of this layer have been studied previously, the inner workings of this layer, and the mechanisms that drive it, are only now becoming clear. With the addition of solar wind, particle, and magnetic field instruments carried by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft, a more detailed analysis has now been completed. Results show the existence of local current sheets in the upper Martian ionosphere in conjunction with the appearance of the second layer. These currents reveal an important magnetic aspect to the transient layer and point to a variety of possible explanations for its formation, including the Kelvin‐Helmholtz instability, magnetic flux ropes, x‐type magnetic reconnection, and solar wind magnetic field rotations.
The thermo‐hydro‐mechanical behavior of the argillaceous Cobourg Limestone
Authors: Selvadurai A. P. S. , Najari M.
Published: April 2017

The Cobourg Limestone is a low‐permeability argillaceous rock that forms a part of the Paleozoic sedimentary sequence found in southern Ontario, Canada. The limestone has a heterogeneous fabric consisting of nodular regions of calcite and dolomite and argillaceous partings of a similar composition but with a low clay content, which gives the appearance of nominal stratifications. The thermo‐hydro‐mechanical (THM) behavior of the rock is of interest to the proposals for using sedimentary formations as candidate rocks for siting deep geological repositories for the storage of heat‐emitting nuclear fuel waste. The paper presents the results of experiments where THM processes were initiated in an intact cylindrical sample of the Cobourg Limestone containing a central cylindrical fluid‐filled cavity. Biot's classical theory of poroelasticity, extended to include thermal effects, is used to examine the THM response of the fluid cavity due to boundary heating of the cylinder. The rise and decay of thermally induced cavity fluid pressure is used to examine the applicability of the THM modeling. The experiments were conducted on cylindrical samples of the Cobourg Limestone with their axes either along or normal to the nominal planes of the argillaceous partings.
Tide‐induced residual circulation in a bay with laterally asymmetric depth
Authors: Kim Bong‐Gwan , Cho Yang‐Ki
Published: April 2017

The tide‐induced residual current is a crucial determinant of the distribution of sediment in a tidally dominated bay. There have been only a few studies of residual currents in bays with laterally asymmetric depth, although the residual circulation in bays with symmetric lateral depth variation has been studied extensively. Gomso Bay is a typical bay with laterally asymmetric depth. The bay is characterized by a deep channel to the north and a wide shoal to the south. This study reports the tide‐induced residual current in Gomso Bay and explains its dynamics using numerical and analytical models. The results from the models are consistent with observations. Residual flows show a clockwise gyre inside the bay and counterclockwise circulation near the mouth. Three physical causes induce residual circulation: (1) bottom friction coupled with a tidal height, (2) advection causing inward residual transport, and (3) a pressure gradient due to a surface slope induced by subtidal flow. The maximum inward residual current is shifted toward the wider shoal. This is caused by across‐channel advection due to the laterally asymmetric depth.
Intraseasonal‐to‐semiannual variability of sea‐surface height in the astern, equatorial Indian Ocean and southern Bay of Bengal
Authors: Cheng Xuhua , McCreary Julian P. , Qiu Bo , Qi Yiquan , Du Yan
Published: April 2017

Intraseasonal‐to‐semiannual variability of sea‐surface height (SSH) in the eastern, equatorial Indian Ocean (EEIO) and southern Bay of Bengal (BoB) is investigated using altimetric data, and solutions to 1½ layer (first baroclinic mode) and linear, continuously stratified (LCS; multibaroclinic‐mode) models. The amplitude and dominant periods of SSH variability differ regionally. Large‐amplitude variability is found along the west coast of Sumatra, in a zonal band across the BoB centered along 5°N, east of Sri Lanka, and in the northwestern BoB, respectively. Along the Sumatran west coast, SSH variability peaks at 30–60, 90, and 180 days. Along 5°N and east of Sri Lanka, the 30–60 day variability is dominant. Sensitivity experiments using a nonlinear version of the 1½ layer model forced by realistic winds reproduce the observed patterns of intraseasonal variability in the southern BoB. At 30–60 days, the solutions show that eddies (nonlinear Rossby waves) propagating from the east, rather than local wind forcing, account for most of the variance east of Sri Lanka; furthermore, they demonstrate that the variance is significantly enhanced by the nonlinear transfer of 90–120 day energy into the intraseasonal band of 30–60 days. The LCS solutions show that the first two baroclinic modes explain most of the SSH variance at 90–180 days. The second baroclinic mode dominates the SSH variance at 180 days, a consequence of basin resonance and strong wind forcing.
Characteristics of ion distribution functions in dipolarizing flux bundles: Event studies
Authors: Runov A. , Angelopoulos V. , Artemyev A. , Birn J. , Pritchett P. L. , Zhou X.‐Z.
Published: April 2017

Taking advantage of multipoint observations from a repeating configuration of the five Time History of Events and Macroscale Interactions during Substorms (THEMIS) probes separated by 1 to 2 Earth radii (RE) along X, Y, and Z in the geocentric solar magnetospheric system (GSM), we study ion distribution functions collected by the probes during three dipolarizing flux bundle (DFB) events observed at geocentric distances 9 < R < 14 RE. By comparing these probes' observations, we characterize changes in the ion distribution functions with respect to probe separation along the X and Y GSM directions and |Bx| levels, which characterize the distance from the neutral sheet. We found that the characteristics of the ion distribution functions strongly depended on the |Bx| level, whereas changes with respect to X and Y were minor. In all three events, ion distribution functions f(v) observed inside DFBs were organized by magnetic and electric fields. The probes near the magnetic equator observed perpendicular anisotropy of the phase space density in the range between thermal energy and twice the thermal energy, although the distribution in the ambient plasma sheet was isotropic. The anisotropic ion distribution in DFBs injected toward the inner magnetosphere may provide the free energy for waves and instabilities, which are important elements of particle energization.
Effect of maleic anhydride‐grafted polypropylene on the flow orientation of short glass fiber in molten polypropylene and on tensile properties of composites
Authors: Uematsu Hideyuki , Suzuki Yu , Iemoto Yoshiyuki , Tanoue Shuichi
Published: April 2017

Composites of polypropylene (PP) and PP blended with maleic anhydride‐grafted polypropylene (MAPP) reinforced with short glass fibers were prepared via extrusion compounding and injection molding techniques. The fiber length did not significantly change irrespective of the presence of MAPP after compounding and injection molding. However, the tensile strength of PP/fiber showed significant improvement after MAPP addition. The interfacial shear strength between PP and fiber increased with the addition of MAPP. Examination of the failure surface of a dumbbell specimen after tensile testing confirmed that the fiber highly orientated in the flow direction in the PP/MAPP matrix. The tensile strength enhancement was attributed to the improvement of the interfacial shear strength between PP and fiber. Moreover, in the injection molding process, there was high orientation of the fiber in the flow direction when there was MAPP. We concluded that the presence of MAPP causes increased orientation of the fiber.
Atomic‐Scale Study of Cation Ordering in Potassium Tungsten Bronze Nanosheets
Authors: Li Luying , Jiang Fan , Tu Fanfan , Jia Shuangfeng , Gao Yihua , Wang Jianbo
Published: April 2017

It has long been accepted that the formation of superlattices in hexagonal‐based potassium tungsten bronzes is attributed to K vacancies only, together with small displacements of W cations. Here, the superlattices within potassium tungsten bronze nanosheets both structurally and spectroscopically at atomic resolution using comprehensive transmission electron microscopy techniques are studied. The multidimensional chemical analyses are realized by energy‐dispersive X‐ray spectroscopy, electron energy‐loss spectroscopy, and X‐ray photoelectron spectroscopy, the atomic‐scale structures are characterized using aberration‐corrected scanning transmission electron microscopy with high‐angle annular‐dark‐field detector. The observed superstructures are mainly attributed to small amount of W vacancies within single atomic layer, which would recover to more uniform distributions of W vacancies with lower concentrations at higher temperature. The band regions of different orientation from the matrix tend to regulate the superstructures to be pinned along the same direction, forming domains of highly ordered structures. The characterization of cation ordering and recovery processes of nanostructures from chemical and structural point of view at atomic resolution enables rational design of optoelectronic devices with controlled physical properties.
Spectral diffusion and scaling of many‐body delocalization transitions
Authors: Gornyi I. V. , Mirlin A. D. , Polyakov D. G. , Burin A. L.
Published: April 2017

We analyze the role of spectral diffusion in the problem of many‐body delocalization in quantum dots and in extended systems. The spectral diffusion parametrically enhances delocalization, modifying the scaling of the delocalization threshold with the interaction coupling constant.

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Synthesis, structure and in vitro anticancer, DNA binding and cleavage activity of palladium (II) complexes based on isatin thiosemicarbazone derivatives
Authors: Ali Amna Qasem , Teoh Siang Guan , Eltayeb Naser Eltaher , Khadeer Ahamed Mohamed B. , Abdul Majid A.M.S. , Almutaleb Arabya A.A.
Published: April 2017

Six novel palladium(II) complexes of a thiosemicarbazone Schiff base with isatin moiety (PdL1 to PdL6) were synthesized by the reaction of palladium(II) with the following: (Z)‐2‐(2‐oxoindolin‐3‐ylidene)‐N‐phenylhydrazinecarbothioamide (L1H), (Z)‐2‐(5‐methyl‐2‐oxoindolin‐3‐ylidene)‐N‐phenylhydrazinecarbothioamide (L2H), (Z)‐2‐(5‐fluoro‐2‐oxoindolin‐3‐ylidene)‐N‐phenylhydrazinecarbothioamide (L3H), (Z)‐N‐methyl‐2‐(5‐nitro‐2‐oxoindolin‐3‐ylidene)hydrazinecarbothioamide (L4H), (Z)‐N‐methyl‐2‐(5‐methyl‐2‐oxoindolin‐3‐ylidene)hydrazinecarbothioamide (L5H) and (Z)‐N‐ethyl‐2‐(5‐methyl‐2‐oxoindolin‐3‐ylidene)hydrazinecarbothioamide (L6H). The structures of these complexes were characterized using elemental analysis and infrared, UV–visible, 1H NMR and mass spectroscopies. The structure of PdL5 was further characterized using single‐crystal X‐ray diffraction. The interaction of these complexes with calf thymus DNA was characterized with a high intrinsic binding constant (Kb = 5.78 × 104 to 1.79 × 106 M−1), which reflected the intercalative activity of these complexes towards calf thymus DNA. This result was also confirmed from viscosity data. Electrophoresis studies revealed that complexes PdL1 to PdL6 could cleave DNA via an oxidative pathway in the presence of an external agent. Data obtained from an in vitro anti‐proliferative study clearly established the anticancer potency of these compounds against the human colorectal carcinoma cell line HCT 116.
Novel structures of Zn(II) biometal cation with the biologically active substituted acetic acid and nitrogen donor ligands: Synthesis, spectral, phosphate diester catalytic hydrolysis and anti‐microbial studies
Authors: Abu Ali Hijazi , Kamel Shayma , Abu Shamma Amani
Published: April 2017

The complexes [Zn(methoxyacetate)21,10‐phenanthroline] 1 and [Zn2(phenylacetate)4(quinoline)2] 2, were prepared and characterized by IR‐spectroscopy, UV–Visible spectroscopy, 1H and 13C NMR spectroscopy, single crystal X‐ray diffraction. BNPP hydrolysis of the complexes and their parent nitrogen ligands were scanned, the results indicated that the hydrolysis rates of BNPP were 4.5 × 104 and 6.2 × 105 for (1) and (2), respectively. In addition, anti‐bacterial activities were scanned to investigate the effect of complexation on their activity against Gram‐positive (S. epidermidis, S. aureus, E. faecalis, M. luteus and B. Subtilis) and Gram‐negative (K. pneumonia, E. coli, P. Mirabilis and P. Aeruginosa) bacteria using agar well‐diffusion method. Complex 1 showed high activity against G−and G+ bacteria except against E. faecalis and P. Aeruginosa. Complex 2 did not show any activity against G− or G+ bacteria.
Long‐term memory in older children/adolescents and adults with autism spectrum disorder
Authors: Williams Diane L. , Minshew Nancy J. , Goldstein Gerald , Mazefsky Carla A.
Published: April 2017

This study extends prior memory reports in autism spectrum disorders (ASD) by investigating memory for narratives after longer recall periods and by examining developmental aspects of narrative memory using a cross‐sectional design. Forty‐seven older children/adolescents with ASD and 31 youth with typical development (TD) and 39 adults with ASD and 45 TD adults were compared on memory for stories from standardized measures appropriate for each age group at three intervals (immediate, 30 min, and 2 day). Both the youth with and without ASD had difficulty with memory for story details with increasing time intervals. More of the youths with ASD performed in the range of impairment when recalling the stories 2 days later as compared to the TD group. The adults with ASD had more difficulty on memory for story details with increasing delay and were poorer at recall of thematic information (needed to create a gist) across the three delay conditions as compared to the TD group. Analyses of the individual results suggested that memory for details of most of the adults with ASD was not impaired when applying a clinical standard; however, a significant percentage of the adults with ASD did not make use of thematic information to organize the narrative information, which would have helped them to remember the stories. The youth with and without ASD performed similarly when both were at a stage of development when memory for details is the primary strategy. The adults with ASD had difficulty with use organizational strategies to support episodic memory. Autism Res 2017, 10: 1523–1532. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.
The forgotten implications of low oil prices on biofuels
Authors: Reboredo Fernando Henrique , Lidon Fernando Cebola , Ramalho José Cochicho , Pessoa Maria Fernanda
Published: April 2017

The sudden drop of oil prices since mid‐2014 has echoed in the news due to implications at national and international levels. For unknown reasons, the effects of quasi permanent low oil prices on biofuels were ignored. With current oil prices, biofuels are not competitive with gasoline, thus the blend wall of regular cars will not rise as soon as expected, and the ethanol's market saturation and the high prices of capital and operational costs are factors that do not contribute to boost consumption. Objections to biofuels subsidies, as well as arguments against the rise of food prices as a consequence of biofuel production from feed crops instead of agricultural and forestry wastes, will become more valid than ever. However, to fulfil biofuel policies regarding energy independence and decarbonization, and in the face of the failure of important advanced biofuel projects, huge public expenditures (incentives/subsidies), extended biofuel mandates, improvement in biofuel technologies, and security for investments through coherent and stable policies are needed. Furthermore, it is advisable to maintain a sustainable conventional biofuel industry to facilitate the transition to advanced biofuels. Citizens must be aware of the indirect costs of fossil fuels (coal mining, pollution, and energy security) and realize that the deployment of biofuels is both a question of opportunity and a challenge. The devastating effect of low oil prices on biofuels and on unconventional oil's exploitation and the constraints to biofuel developments, are still in the horizon, especially when OPEC will no longer act as the swing oil producer. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
An integrated network analysis identifies how ArcAB enables metabolic oscillations in the nitric oxide detoxification network of Escherichia coli
Authors: Sacco Sarah A. , Adolfsen Kristin J. , Brynildsen Mark P.
Published: April 2017

The virulences of many pathogens depend on their abilities to detoxify the immune antimicrobial nitric oxide (NO•). The functions of bacterial NO• detoxification machinery depend on oxygen (O2), with O2 inhibiting some enzymes, whereas others use it as a substrate. Previously, Escherichia coli NO• detoxification was found to be highly attenuated under microaerobic conditions and metabolic oscillations were observed. The oscillations in [NO•] and [O2] were found to result from the inhibitory action of NO• on aerobic respiration, the catalytic inactivation of NO• by Hmp (an NO• dioxygenase), and an imbalanced competition for O2 between Hmp and cytochrome terminal oxidase activity. Here the authors investigated the role of the ArcAB two component system (TCS) in microaerobic NO• detoxification. The authors observed that wild‐type, ΔarcA, and ΔarcB had comparable initial NO• clearance times; however, the mutant cultures failed to exhibit [NO•] and [O2] oscillations. Using an approach that employed experimentation and computational modeling, the authors found that the loss of oscillations in ΔarcA was due to insufficient induction of cytochrome bd‐I expression. Collectively, these results establish ArcAB as a TCS that influences NO• detoxification in E. coli within the physiologically‐relevant microaerobic regime.
Virchow's node together with an Irish node
Authors: Toh Yoon Ezekiel Wong , Nishihara Kazuki
Published: April 2017

Key Clinical Message

Classical lymphadenopathies, such as Virchow's node (left supraclavicular lymph node metastasis) and Irish node (left axillary lymph node metastasis), are important findings that may indicate the presence of gastric cancer and other gastrointestinal malignancies.
Bottom‐up Design of High‐Performance Pt Electrocatalysts Supported on Carbon Nanotubes with Homogeneous Ionomer Distribution
Authors: Yang Zehui , Li Jing , Ling Ying , Zhang Quan , Yu Xinxin , Cai Weiwei
Published: April 2017

Homogeneous ionomer networks are primarily important for the enhancement of fuel cell performance. Here, we report a bottom‐up design of platinum (Pt) electrocatalysts with homogeneous ionomer layers, in which Pt nanoparticles are deposited on carbon nanotubes (CNTs) after sequentially wrapping with polybenzimidazole (PBI) and end‐capped hyperbranched sulfonated macromolecules (E‐HBM) (CNT/PBI/E‐HBM/Pt). E‐HBM, which are proton conductive macromolecules, are homogeneously coated on CNTs owing to the base–acid interaction between PBI and E‐HBM. The durability and oxygen reduction reaction (ORR) results indicate that CNT/PBI/E‐HBM/Pt exhibits higher Pt stability and ORR activity compared with the electrocatalyst without E‐BHM. The Nafion ionomer‐free membrane electrode assembly (MEA) fabricated from CNT/PBI/E‐HBM/Pt (704 mW cm−2) shows higher power density than the MEA from CNT/PBI/Pt with Nafion ionomer (30 wt %, 603 mW cm−2) owing to the unique bottom‐up design resulting in high Pt utilization efficiency.
A Water‐Stable Dual‐Channel Luminescence Sensor for UO22+ Ions Based on an Anionic Terbium(III) Metal–Organic Framework
Authors: Ye Junwei , Bogale Raji F. , Shi Yangwei , Chen Yanzhen , Liu Xigang , Zhang Siqi , Yang Yaoyao , Zhao Jianzhang , Ning Guiling
Published: April 2017

A stable 3D TbIII‐based metal–organic framework [Tb(BPDC)2]⋅(CH3)2NH2 (DUT‐101) was synthesized, and it is the first efficient dual‐channel luminescence sensor for aqueous UO22+ ions. DUT‐101 contains an anionic three‐dimensional framework and protonated dimethylamine molecules embedded within the channels. The intense green emission of DUT‐101 could be highly selectively and sensitively quenched by UO22+ ions even in the presence of other competing metal ions. A possible sensing mechanism was proposed based on both suppression of luminescence resonance energy transfer and enhancement of intermolecular electron transfer. Furthermore, visual green fluorescent test papers based on DUT‐101 were fabricated and could be used to discriminate UO22+ ions among various metal ions.
Tumor Targeting with an isoDGR–Drug Conjugate
Authors: Zanella Simone , Angerani Simona , Pina Arianna , López Rivas Paula , Giannini Clelia , Panzeri Silvia , Arosio Daniela , Caruso Michele , Gasparri Fabio , Fraietta Ivan , Albanese Clara , Marsiglio Aurelio , Pignataro Luca , Belvisi Laura , Piarulli Umberto , Gennari Cesare
Published: April 2017

Herein we report the first example of an isoDGR–drug conjugate (2), designed to release paclitaxel selectively within cancer cells expressing integrin αVβ3. Conjugate 2 was synthesized by connecting the isoDGR peptidomimetic 5 with paclitaxel via the lysosomally cleavable Val–Ala dipeptide linker. Conjugate 2 displayed a low nanomolar affinity for the purified integrin αVβ3 receptor (IC50=11.0 nm). The tumor targeting ability of conjugate 2 was assessed in vitro in anti‐proliferative assays on two isogenic cancer cell lines characterized by different integrin αVβ3 expression: human glioblastoma U87 (αVβ3+) and U87 β3‐KO (αVβ3−). The isoDGR‐PTX conjugate 2 displayed a remarkable targeting index (TI=9.9), especially when compared to the strictly related RGD‐PTX conjugate 4 (TI=2.4).
Catalyst Screening and Reactor Modeling for Oxidative Methane Coupling to Increase the Heating Value of Biogas
Authors: Friedel Marcus , Nitzsche Jörg , Krause Hartmut
Published: April 2017

Die Einspeisung von Biogas in das Erdgasnetz kann einen entscheidenden Anteil zum Gelingen der Energiewende beitragen, da Biogas hierdurch für verschiedene Sektoren (Mobilität, Industrie und Gaskraftwerke) nutzbar wird. Die in der Regel vor der Einspeisung durchgeführte Brennwertanhebung mit Flüssiggas verursacht jedoch hohe Kosten und Abhängigkeiten von fossilen Energieträgern. Um eine unabhängige Brennwertanhebung zu ermöglichen wird derzeit das Verfahren der oxidativen Kopplung von Methan zur Erzeugung höherer Kohlenwasserstoffe aus Biogas untersucht.
miR‐130A as a diagnostic marker to differentiate malignant mesothelioma from lung adenocarcinoma in pleural effusion cytology
Authors: Cappellesso Rocco , Galasso Marco , Nicolè Lorenzo , Dabrilli Paolo , Volinia Stefano , Fassina Ambrogio
Published: April 2017

BACKGROUND

Malignant pleural mesothelioma is a rare tumor with a dismal prognosis, usually presenting with recurrent effusions. However, the majority of malignant pleural effusions are due to lung adenocarcinoma (AdC). The distinction between these tumors has considerable therapeutic and medicolegal implications and can be very challenging both histologically and cytologically. Appropriate immunohistochemistry (IHC) is required to support the diagnosis. MicroRNA (miRNA) expression analysis could be a viable diagnostic tool for distinguishing between these tumors. The purpose of the current study was to assess the reliability of miRNAs as diagnostic markers to differentiate epithelioid malignant mesothelioma (MM) from lung AdC.

METHODS

Bioinformatic analysis of publicly searchable data sets regarding miRNA expression profiling was performed to select the most significant differentially expressed miRNAs. These were analyzed by quantitative polymerase chain reaction on histologic (41 MM cases and 40 lung AdC cases) and cytological (26 MM cases and 27 lung AdC cases) specimens and the diagnostic performances were assessed.

RESULTS

miR‐130a, miR‐193a, miR‐675, miR‐141, miR‐205, and miR‐375 were found to be the best distinguishing markers. Of these, only miR‐130a was significantly overexpressed in MM compared with lung AdC (P =.029 in histologic and P =.014 in cytological samples). miR‐130a demonstrated a sensitivity of 77%, a specificity of 67%, a positive predictive value of 69%, a negative predictive value of 75%, and an accuracy of 72% in identifying MM.

CONCLUSIONS

The diagnostic performances of miR‐130a expression analysis and IHC appear to be similar. miR‐130a quantification could be used reliably as second‐level diagnostic tool to differentiate MM from lung AdC in pleural effusion cytology, mainly in those cases with ambiguous or negative IHC. Further validation is needed. Cancer Cytopathol 2017;125:635‐43. © 2017 American Cancer Society.
Pyrrolo[3,2‐b]pyrrole as the Central Core of the Electron Donor for Solution‐Processed Organic Solar Cells
Authors: Domínguez Rocío , Montcada Núria F. , de la Cruz Pilar , Palomares Emilio , Langa Fernando
Published: April 2017

A series of three small‐molecule acceptor–donor–acceptor (A‐D‐A) compounds with a tetraaryl‐1,4‐dihydropyrrolo[3,2‐b]pyrrole as the central building block were synthesized and fully characterized. These molecules present high thermal stability and suitable HOMO–LUMO energy levels making them feasible electron‐donor materials in bulk heterojunction organic solar cells (BHJ‐OSC). Moreover, theoretical work predicts of a lack of planarity and no π–π stacking, furthermore. The electron density of the HOMO is distributed on the pyrrole–pyrrole moiety and that of the LUMO is delocalized, in contrast, on the phenyl groups. The organic solar cells deliver an open‐circuit voltage of 0.99 V. However, the overall efficiency is limited due to the low charge mobility measured for holes, 10−9 cm2 V−1 s−1.
Carbon doped GaN layers grown by Pseudo‐Halide Vapour Phase Epitaxy
Authors: Siche Dietmar , Zwierz Radoslaw , Kachel Krzysztof , Jankowski Nadja , Nenstiel Christian , Callsen Gordon , Bickermann Matthias , Hoffmann Axel
Published: April 2017

Pseudo‐Halide Vapour Phase Epitaxy (PHVPE) was utilized to grow thick carbon doped GaN layers to study their suitability as semi‐insulating (SI) substrates. With in‐situ waste gas analysis by FTIR spectroscopy, the carbon doping from the HCN precursor gas was indirectly controlled in a wide range up to 5 × 1019 cm–3. The grown layers were characterized by Scanning Electron Microscopy (SEM), Secondary Ion Mass Spectroscopy (SIMS), Photoluminescence (PL), Micro‐Raman‐Spectroscopy, Hall effect measurement, and High Resolution X‐Ray Diffractometry (HRXRD). Similar to the impurity incorporation (O, Si, Mg and Zn), carbon distribution proved to be inhomogeneous, due to its increased incorporation on facets of so‐called V‐pits.
Individual‐based analysis of hair corticosterone reveals factors influencing chronic stress in the American pika
Authors: Waterhouse Matthew D. , Sjodin Bryson , Ray Chris , Erb Liesl , Wilkening Jennifer , Russello Michael A.
Published: April 2017

Glucocorticoids are often measured in wildlife to assess physiological responses to environmental or ecological stress. Hair, blood, saliva, or fecal samples are generally used depending on the timescale of the stress response being investigated and species‐specific considerations. Here, we report the first use of hair samples to measure long‐term corticosterone levels in the climate‐sensitive American pika (Ochotona princeps). We validated an immunoassay‐based measurement of corticosterone extracted from hair samples and compared corticosterone estimates obtained from plasma, hair, and fecal samples of nine pikas. To demonstrate an ecological application of this technique, we characterized physiological stress in 49 pikas sampled and released at eight sites along two elevational transects. Microclimate variation was measured at each site using both ambient and subsurface temperature sensors. We used an information theoretic approach to compare support for linear, mixed‐effects models relating corticosterone estimates to microclimate, body size, and sex. Corticosterone was measured accurately in pika hair samples after correcting for the influence of sample mass on corticosterone extraction efficiency. Hair‐ and plasma‐based estimates of corticosterone were weakly correlated. The best‐supported model suggested that corticosterone was lower in larger, male pikas, and at locations with higher ambient temperatures in summer. Our results are consistent with a general negative relationship between body mass and glucocorticoid concentration observed across mammalian species, attributed to the higher mass‐specific metabolic rates of smaller bodied animals. The higher corticosterone levels in female pikas likely reflected the physiological demands of reproduction, as observed in a wide array of mammalian species. Additionally, we establish the first direct physiological evidence for thermal stress in the American pika through nonlethal sampling of corticosterone. Interestingly, our data suggest evidence for cold stress likely induced during the summer molting period. This technique should provide a useful tool to researchers wishing to assess chronic stress in climate‐sensitive mammals.
Thermostable 1D Lanthanide 4‐Phenylbenzoate Polymers [Ln(4‐phbz)3]n (Ln = Sm, Eu, Gd, Tb, Dy, Ho) with Isolated Metal Chains: Synthesis, Structure, Luminescence, and Magnetic Properties
Authors: Evstifeev Igor S. , Efimov Nikolay N. , Varaksina Evgenia A. , Taydakov Ilya V. , Mironov Vladimir S. , Dobrokhotova Zhanna V. , Aleksandrov Grygory G. , Kiskin Mikhail A. , Eremenko Igor L.
Published: April 2017

New 1D polymers, with the general formula [Ln(4‐phbz)3]n, where Ln = Sm, Eu, Gd, Tb, Dy, Ho, and 4‐phbz is the 4‐phenylbenzoate anion, were synthesized by the reaction of Ln(NO3)3·xH2O, 4‐phenylbenzoic acid, and dry KOH. Thermal analysis shows that [Eu(4‐phbz)3]n is thermally stable under an inert gas up to 350 °C, and it melts at 297 °C. It is shown that the 4‐phenylbenzoate anion [E(T1) ≈ 22500 cm–1] in [Ln(4‐phbz)3]n can play the role of an antenna and sensitize the luminescence of Eu3+ and Tb3+ ions. Analysis of the magnetic data of the [Gd(4‐phbz)3]n complex reveals weak antiferromagnetic coupling between Gd3+ ions (J = –0.053 cm–1). The [Dy(4‐phbz)3]n compound shows noticeable frequency‐dependent χ′′ signals, indicating slow magnetic relaxation and single‐molecule magnet behavior, with an energy barrier of ΔEeff/kB = 5 K.
Enantioselective Synthesis of Chiral Pyrazolo[3,4‐d]azepin‐7(2H,4H,8H)‐one Derivatives through a Sequential Michael Addition and Reductive Ring‐Closing Strategy
Authors: Xu Yan , Sun Panpan , Song Qing , Lai Xiaoyan , Liu Wei , Xia Tao , Huang Yiyong , Shen Yongcun
Published: April 2017

The asymmetric Michael addition of ethyl (5‐oxo‐1‐phenyl‐4,5‐dihydro‐1H‐pyrazol‐3‐yl)acetate to nitroalkenes catalyzed by a squaramide organocatalyst to give chiral pyrazoles was studied. Subsequent one‐pot reductive ring closing in the same pot gave a series of biologically important chiral pyrazolones with seven‐membered lactam frameworks in good yields with excellent enantioselectivities (up to 99 % ee).
Enantioselective synthesis and sensory properties of 3‐methylthiodecanal
Authors: Jiang Yaolin , Liu Hao , Liu Yongguo , Yang Shaoxiang , Sun Baoguo , Tian Hongyu
Published: April 2017

The enantioselective synthesis of two enantiomers of 3‐methylthiodecanal was described, in which the optically active 1‐undecen‐4‐ols prepared by asymmetric catalytic addition of n‐octanal with allyltributylstannane went through oxidation of double bond and nucleophilic substitution of hydroxy group via mesylate to afford the target molecules with about 90% ee values. Odour properties and approximate thresholds were determined by means of GC/Olfactory. The data indicated that two enantiomers of 3‐methylthiodecanal presented distinctive odour feature from each other and also a slight difference in odour intensity.
Investigation of volatile components and identification of the most potent odour‐active component in fermented meat sauce
Authors: Ohata Motoko , Zhou Lanxi , Higuchi Kaori , Nagai Tsugumi , Kasamatsu Hiroko , Arihara Keizo
Published: April 2017

The present study investigated the volatile constituents of fermented meat sauce (FMS) and identified some of the potent odour‐active components. The FMS was prepared by fermenting a mixture of ground pork, koji, and salt for 12 months. After 12 months' fermentation, four potent odour components: 3‐hydroxy‐4,5‐dimethyl‐2(5H)‐furanone (sotolon), 4‐hydroxy‐2(or 5)‐ethyl‐5(or 2)‐methyl‐3(2H)‐furanone (ethyl furaneol), 4‐hydroxy‐2,5‐dimethyl‐3(2H)‐furanone, and 3‐methylbutanoic acid, were found in FMS by gas chromatography‐olfactometry analysis. The most characteristic components were sotolon and ethyl furaneol and contributed strongly to the FMS odour. These two components were detected in the FMS after 6 and 9 months' fermentation, respectively; especially sotolon concentration was 147.43 mg/l after 12 months' fermentation. These components were generated by fermentation and might play an important role in the FMS odour after 12 months' fermentation.
An HPLC method for the detection of hydro peroxides derived from linalyl acetate in citrus oils, using post‐column luminol‐mediated chemiluminescence detection
Authors: Calandra Michael J. , Wang Ying
Published: April 2017

Linalyl acetate is an unsaturated terpene commonly found in many essential oils, and it is easily oxidized by atmospheric oxygen to form hydroperoxides. The hydroperoxides of linalyl acetate are known to be sensitizers capable of causing allergic contact dermatitis. The standard iodometric titration methods (peroxide value [POV] methods) typically used to measure hydroperoxide levels in essential oils provide only a total level of all oxidizing species, including hydroperoxides. These POV methods are not capable of species differentiation and therefore may not reliably correlate well with the dermatological sensitizing potency of a particular sample. This laboratory has previously reported a high‐performance liquid chromatographic method using a post‐column chemiluminescent reaction to detect hydroperoxides derived from limonene and linalool. Herein we report that this same method is also useful for the detection of hydroperoxides derived from linalyl acetate.
Valuing productivity costs using the friction‐cost approach: Estimating friction‐period estimates by occupational classifications for the UK
Authors: Kigozi Jesse , Jowett Sue , Lewis Martyn , Barton Pelham , Coast Joanna
Published: April 2017

The friction cost approach has been proposed as an alternative to the human capital approach in estimating productivity costs. However, it is difficult, in practice, to apply this approach due to limited availability of context‐specific data. Using national and firm‐level data on vacancy durations sourced from 4 organisations, we estimated vacancy durations, and consequently, length of friction period for the United Kingdom disaggregated by occupational classification. We found comparable estimates to previously reported friction periods elsewhere. The disaggregated friction period analysis confirmed occupational class has an effect on the estimated length of the friction period. The research presents estimates on vacancy durations and friction periods necessary to use the friction cost approach in a practical way in economic evaluations.
Ventral, but not dorsal, hippocampus inactivation impairs reward memory expression and retrieval in contexts defined by proximal cues
Authors: Riaz Sadia , Schumacher Anett , Sivagurunathan Seyon , Van Der Meer Matthijs , Ito Rutsuko
Published: April 2017

The hippocampus (HPC) has been widely implicated in the contextual control of appetitive and aversive conditioning. However, whole hippocampal lesions do not invariably impair all forms of contextual processing, as in the case of complex biconditional context discrimination, leading to contention over the exact nature of the contribution of the HPC in contextual processing. Moreover, the increasingly well‐established functional dissociation between the dorsal (dHPC) and ventral (vHPC) subregions of the HPC has been largely overlooked in the existing literature on hippocampal‐based contextual memory processing in appetitively motivated tasks. Thus, the present study sought to investigate the individual roles of the dHPC and the vHPC in contextual biconditional discrimination (CBD) performance and memory retrieval. To this end, we examined the effects of transient post‐acquisition pharmacological inactivation (using a combination of GABAA and GABAB receptor agonists muscimol and baclofen) of functionally distinct subregions of the HPC (CA1/CA3 subfields of the dHPC and vHPC) on CBD memory retrieval. Additional behavioral assays including novelty preference, light‐dark box and locomotor activity test were also performed to confirm that the respective sites of inactivation were functionally silent. We observed robust deficits in CBD performance and memory retrieval following inactivation of the vHPC, but not the dHPC. Our data provides novel insight into the differential roles of the ventral and dorsal HPC in reward contextual processing, under conditions in which the context is defined by proximal cues.
The Role of the Nuclear Envelope Protein MAN1 in Mesenchymal Stem Cell Differentiation
Authors: Bermeo Sandra , Al‐Saedi Ahmed , Kassem Moustapha , Vidal Christopher , Duque Gustavo
Published: April 2017

Mutations in MAN1, a protein of the nuclear envelope, cause bone phenotypes characterized by hyperostosis. The mechanism of this pro‐osteogenic phenotype remains unknown. We increased and decreased MAN1 expression in mesenchymal stem cells (MSC) upon which standard osteogenic and adipogenic differentiation were performed. MAN1 knockdown increased osteogenesis and mineralization. In contrast, osteogenesis remained stable upon MAN1 overexpression. Regarding a mechanism, we found that low levels of MAN1 facilitated the nuclear accumulation of regulatory smads and smads‐related complexes, with a concurrently high expression of nuclear β‐Catenin. In addition, we found adipogenesis to be decreased in both conditions, although predominantly affected by MAN1 overexpression. Finally, lamin A, a protein of the nuclear envelope that regulates MSC differentiation, was unaffected by changes in MAN1. In conclusion, our studies demonstrated that lower levels of MAN1 in differentiating MSC are associated with higher osteogenesis and lower adipogenesis. High levels of MAN1 only affected adipogenesis. These effects could have an important role in the understanding of the role of the proteins of the nuclear envelope in bone formation. J. Cell. Biochem. 118: 4425–4435, 2017. © 2017 Wiley Periodicals, Inc.