bluuebunny/crossref_metadata_2025 huggingface dataset:
What You Say Matters
Authors: Hoover Kristen
Published: March 2015

This Teaching Tip will explain an initiative, Global Book Hour, that engages families in a global literature read aloud. GBH integrates social studies, the visual and performing arts, healthy eating, and vocabulary development as children travel the world through high quality global children's literature. The program is a non‐traditional, rich literacy experience, and has multiple, strong community partners that include a grocery store and a laundromat. Because many of the children who attend GBH are immigrants and refugees, an added benefit of the read aloud and discussions is helping the children identify with characters in the story. Though this program is located in the community, it can be easily replicated in a school setting. In this article, the program is described, connections to the Common Core State Standards are identified, and suggestions for starting a GBH are included.
Re: Single fetal demise in monochorionic pregnancies: incidence and patterns of cerebral injury. J. M. M. van Klink, A. van Steenis, S. J. Steggerda, L. Genova, M. Sueters, D. Oepkes and E. Lopriore. Ultrasound Obstet Gynecol 2015; 45: 294–300
Authors: Jani J. C.
Published: March 2015

Linked Comment: Ultrasound Obstet Gynecol 2015; 45: 294–300
Re: High‐intensity focused ultrasound applied to the placenta using a toroidal transducer: a preliminary ex‐vivo study. J. Caloone, C. Huissoud, J. Vincenot, A. Kocot, C. Dehay, J. Y. Chapelon, R. C. Rudigoz and D. Melodelima. Ultrasound Obstet Gynecol 2015; 45: 313–319
Authors: Brezinka C.
Published: March 2015

Linked Comment: Ultrasound Obstet Gynecol 2015; 45: 313–319
A mist‐net method for capturing harlequin ducks on rivers
Authors: Smith Cyndi M. , Trimper Perry G. , Bate Lisa J. , Brodeur Serge , Hansen Warren K. , Robert Michel
Published: March 2015

Many sea ducks are captured during wing molt at intertidal areas; however, to study the breeding ecology of some species, researchers need to capture them on streams and rivers, which are often flowing with high water. In fast‐flowing and deep water, wading streams during net set‐up and extraction of birds is impossible to complete safely. Between 1995 and 2013, we captured 720 adult and 241 hatch‐year harlequin ducks (Histrionicus histrionicus) on 37 streams in eastern and western North America. We used a mist net extended across the stream with modified riggings that allowed above‐water retrieval of captured birds without technicians entering the stream. This method can be used across deep, fast water that is not wadable; requires equipment that is compact and easily transported; is suitable for remote areas; can be operated by a crew of 4–6 people; and has a low risk of injury to the birds. Care must be taken when using this method to capture large numbers of ducks simultaneously because it becomes difficult to keep the birds above the fast water. This capture method could be used for other ducks, and with different mesh sizes could also be used for other birds, such as American dippers (Cinclus americanus) and spotted sandpipers (Actitis macularius), at these inland locations. The mobility of this capture method means that species and individuals that are not of interest can be avoided by orienting the net to a horizontal position to allow non‐target species to pass by unhindered. © 2015 The Wildlife Society.
Synthesis, Crystal Structure, Fluorescence and Photocatalytic Properties of a Copper Compound with 2‐Phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene and Silicotungstic Acid
Authors: Xu Dongbo , Luo Bifu , Chen Min , Meng Suci , Wu Yunlong , Jiang Deli
Published: March 2015

The polyoxometalate compound [CuPTCP(H2O)2.5]2[SiW12O40]·10.5H2O (1) was synthesized under hydrothermal conditions using 2‐phenyl‐1H‐1,3,7,8‐tetraazacyclopenta[l]phenanthrene (PTCP) and Keggin‐type silicotungstic acid (H4SiW12O4) as neutral ligands. Compound 1 was characterized by single‐crystal X‐ray diffraction, elemental analysis, as well as IR and UV/Vis spectroscopy. It crystallizes in the orthorhombic space group Cmcm with a = 15.490(8) nm, b = 25.263(8) nm, c = 20.988(8) nm, α = 90°, β = 90°, γ = 90°, V = 8213(6) nm3, Z = 2. Compared with the ligand PTCP, the fluorescent spectra of compound 1 are different. Furthermore, the Rhodamine B (RhB) photodegration process by compound 1 as catalyst was studied. It could be shown that the DR% of compound 1 is more than twice that of pure silicotungstic acid.
Urmylation and tRNA thiolation functions of ubiquitin‐like Uba4·Urm1 systems are conserved from yeast to man
Authors: Jüdes André , Ebert Folke , Bär Christian , Thüring Kathrin L. , Harrer Aileen , Klassen Roland , Helm Mark , Stark Michael J.R. , Schaffrath Raffael
Published: March 2015

The ubiquitin‐like protein Urm1 from budding yeast and its E1‐like activator Uba4 have dual roles in protein urmylation and tRNA thiolation pathways. To study whether these are conserved among eukaryotes, we used gene shuffles to replace the yeast proteins by their human counterparts, hURM1 and hUBA4/MOCS3. As judged from biochemical and genetical assays, hURM1 and hUBA4 are functional in yeast, albeit at reduced efficiencies. They mediate urmylation of the peroxiredoxin Ahp1, a known urmylation target in yeast, and support tRNA thiolation. Similar to hUBA4, yeast Uba4 itself is modified by Urm1 and hURM1 suggesting target overlap between eukaryal urmylation pathways. In sum, our study shows that dual‐function ubiquitin‐like Urm1·Uba4 systems are conserved and exchangeable between human and yeast cells.
Identification of Methicillin-Susceptible or Methicillin-ResistantStaphylococcus aureusCarrier Status Preoperatively Using Polymerase Chain Reaction in Patients Undergoing Elective Surgery With Hardware Implantation
Authors: Bebko Serge P. , Byers Patricia , Green David M. , Awad Samir S.
Published: March 2015

We compared bedside polymerase chain reaction to culture for identifyingStaphylococcus aureusin patients about to undergo surgery with hardware implantation. Patients were screened forS. aureuscarrier status at the preoperative clinic and on the day of surgery. The sensitivity, specificity, positive and negative predictive values, and accuracy were calculated.

Infect Control Hosp Epidemiol2015;00(0): 1–4
The relation of feedback-seeking motives and emotion regulation strategies to front-line managers’ feedback source profiles: A person-centered approach
Authors: Qian Jing , Han Zhuo R , Guo Zhichao , Yang Fu , Wang Haiwan , Wang Qiuyue
Published: March 2015

Although the current literature offers some preliminary information about seeking feedback from various sources, a variable-centered approach has been adopted in which seeking feedback from supervisors and from subordinates was treated separately. We endeavored to extend this work through model-based cluster analysis, a person-centered approach, to identify distinct feedback source profiles in our sample of 209 front-line manager–supervisor dyads. Additionally, we aimed to explore whether such profiles differed between two feedback motives, perceived instrumental value and perceived image cost, as well as managers’ emotion regulation strategies. Results revealed six feedback source profiles and such profiles are associated not only with their perceived image cost and instrumental value but also with their emotion regulation strategies.
Effects of lexical semantics on acoustic prominence
Authors: LEWIS MOLLY L. , WATSON DUANE G.
Published: March 2015

abstract

This paper explores the representations underlying lexical semantics. In particular, we test whether a word’s meaning can affect a word’s articulation. In Experiment 1, participants produced high-effort (e.g.,yelling) and low-effort (e.g.,chatting) words that are semantically related to articulation, as well as words that are semantically unrelated to articulation (e.g.,kicking). We found that vocal words were produced with greater intensity than non-vocal words. In Experiment 2, we explored the specificity of this effect by investigating how words semantically related to the mouth, but unrelated to vocalization (e.g.,chewing) were articulated. Analyses revealed that mouth words did not differ from controls, and we replicated the vocal effects from Experiment 1, suggesting fine-grain motor activation from lexical semantics. Experiment 3 revealed that the semantics of a verb influences the prosodic intensity of a sentence prior to the onset of the verb. Together, these data suggest aspects of lexical meaning influence prosody, and that motor representations may underlie lexical semantics.
Presidential Particularism and Divide-the-Dollar Politics
Authors: KRINER DOUGLAS L. , REEVES ANDREW
Published: March 2015

When influencing the allocation of federal dollars across the country, do presidents strictly pursue maximally efficient outcomes, or do they systematically target dollars to politically influential constituencies? In a county-level analysis of federal spending from 1984 to 2008, we find that presidents are not universalistic, but particularistic—that is, they reliably direct dollars to specific constituents to further their political goals. As others have noted, presidents target districts represented by their co-partisans in Congress in the pursuit of influencevis-à-visthe legislature. But we show that, at much higher levels, presidents target both counties within swing states and counties in core states that strongly supported the president in recent elections. Swing state particularism is especially salient during presidential reelection years, and core partisan counties within swing states are most heavily rewarded. Rather than strictly pursuing visions of good public policy or pandering to the national median voter, our results suggest that presidents systematically prioritize the needs of politically important constituents.
Partisanship and the Allocation of Federal Spending: Do Same-Party Legislators or Voters Benefit from Shared Party Affiliation with the President and House Majority?
Authors: DYNES ADAM M. , HUBER GREGORY A.
Published: March 2015

Previous research finds that House majority members and members in the president's party garner additional federal spending in their districts. Using federal spending data in individual districts, we implement two research designs to distinguish elected officials enacting policies that benefit like-minded voters—the party in the electorate—from those that benefit same-party elected officials—the party in government. We find robust evidence that presidential partisanship is associated with large differences in spending correlated with voter preferences, but little evidence that presidents favor areas represented by their party in the House. By contrast, control of the House is associated with differences in spending by voter preferences and with modest increases in spending in districts held by members of the majority. These findings have important implications for understanding presidential influence, as well as the role of parties in the House and in coordinating between elected branches.
Examining the potential for climate change mitigation from zero tillage
Authors: MANGALASSERY S. , SJÖGERSTEN S. , SPARKES D. L. , MOONEY S. J.
Published: March 2015

The benefits of reduced and zero-tillage systems have been presented as reducing runoff, enhancing water retention and preventing soil erosion. There is also general agreement that the practice can conserve and enhance soil organic carbon (C) levels to some extent. However, their applicability in mitigating climate change has been debated extensively, especially when the whole profile of C in the soil is considered, along with a reported risk of enhanced nitrous oxide (N2O) emissions. The current paper presents a meta-analysis of existing literature to ascertain the climate change mitigation opportunities offered by minimizing tillage operations. Research suggests zero tillage is effective in sequestering C in both soil surface and sub-soil layers in tropical and temperate conditions. The C sequestration rate in tropical soils can be about five times higher than in temperate soils. In tropical soils, C accumulation is generally correlated with the duration of tillage. Reduced N2O emissions under long-term zero tillage have been reported in the literature but significant variability exists in the N2O flux information. Long-term, location-specific studies are needed urgently to determine the precise role of zero tillage in driving N2O fluxes. Considering the wide variety of crops utilized in zero-tillage studies, for example maize, barley, soybean and winter wheat, only soybean has been reported to show an increase in yield with zero tillage (7·7% over 10 years). In several cases yield reductions have been recorded e.g. c. 1–8% over 10 years under winter wheat and barley, respectively, suggesting zero tillage does not bring appreciable changes in yield but that the difference between the two approaches may be small. A key question that remains to be answered is: are any potential reductions in yield acceptable in the quest to mitigate climate change, given the importance of global food security?
Neck dissection: cause and effect
Authors: Hirshoren N , Ashqar F , Weinberger J M , Eliashar R
Published: March 2015

Objective:

This study aimed to evaluate changes in neck dissection procedures over time in a tertiary university hospital to determine their influence on residency training.

Methods:

Neck dissections performed in a recent decade (2003–2012) were retrospectively analysed and compared with those of an earlier decade (1981–1990).

Results:

Nowadays, neck dissections are most frequently performed for thyroid (2003–2012 vs 1981–1990: 60.7 per cent vs 25 per cent, p = 0.002) and less often for epithelial malignancies (23.2 per cent vs 53.5 per cent, p = 0.002). Compared with dissections for thyroid spread, more dissections for epithelial malignancies are extensive (epithelial vs thyroid malignancies, 66 per cent vs 4.9 per cent) and more are performed after chemoradiation failures (25.6 per cent vs 0 per cent).

Conclusion:

This study demonstrates changes in neck dissection procedures over time. There is an increasing preference for conservative treatment for epithelial cancers. In addition, there is a large increase in both the diagnosis and surgical treatment of thyroid cancer. This shift may have a great effect on residents’ learning curves and on their ability to achieve competency in performing neck dissections.
An introduction to reasoning over qualitative multi-attribute preferences
Authors: Nunes Ingrid , Miles Simon , Luck Michael , Lucena Carlos J. P.
Published: March 2015

Research on preferences has significantly increased in recent years, as it involves not only many subproblems to be investigated, such as elicitation, representation, and reasoning, but has also been the target of different research areas, for example, artificial intelligence and databases. In particular, much work has focused on qualitative preferences, because these are closer to the way people express their preferences in comparison with quantitative preferences. Against this background, a large number of approaches have been proposed, associated with heterogeneous areas, so that these approaches are usually just compared with those of the same area. In response, we present in this paper a survey of approaches toqualitative multi-attribute preference reasoning, covering different research areas. We introduce selected approaches that propose different techniques and algorithms, which take as input qualitative multi-attribute preference statements following a particular structure specified by the approach. We analyse each approach in a systematic way and discuss their commonalities and limitations.
A Robust Navigation Technique for Integration in the Guidance and Control of an Uninhabited Surface Vehicle
Authors: Annamalai A. , Motwani A. , Sharma S.K. , Sutton R. , Culverhouse P. , Yang C.
Published: March 2015

This paper proposes the novel use of a weighted Interval Kalman Filter (wIKF) in a robust navigational approach for integration with the guidance and control systems of an uninhabited surface vehicle named Springer. The waypoint tracking capability of this technique is compared with that of one that uses a conventional Kalman Filter (KF) navigational design, when the model of the sensing equipment used by the filter is incorrect. In this case, the KF fails to predict correctly the vehicle's heading, which consequently impacts negatively on the performance of its integrated navigation, guidance and control (NGC). However, the use of a wIKF technique that is immune to this kind of erroneous modelling endows the integrated NGC system with better accuracy and efficiency in completing a mission.
Hiroo Kanamori Receives 2014 William Bowie Medal
Authors:   AGU
Published: March 2015

Hiroo Kanamori was awarded the 2014 William Bowie Medal, AGU’s highest honor.
Smartphone App Seeks to Make Navigation Safer
Authors: O'Hanlon Larry
Published: March 2015

The app sends local magnetic field strength along with your phone's position and orientation to scientists, who use the data to fine-tune magnetic field models.
Measurements, Modeling, and Scaling of Inland Water Gas Exchange
Authors: Desai Ankur Rashmikant , Vessala Timo , Rantakari Miitta
Published: March 2015

Advancing the Science of Gas Exchange Between Fresh Waters and the Atmosphere; Hyytiälä Forestry Field Station, Korkeakoski, Finland, 15–19 September 2014
NSF Geosciences Report Provides Updated Roadmap
Authors: Showstack Randy
Published: March 2015

Core research programs and key imperatives are stressed in a new report by the National Science Foundation’s Advisory Committee for the Geosciences.
Probing Exoplanet Interiors Through Lab Simulations
Authors: Wendel JoAnna
Published: March 2015

Laser-driven experiments on silica help scientists learn more about planetary formation and evolution.
White House Budget Calls for Increased Science Funding
Authors: Showstack Randy
Published: March 2015

The FY 2016 federal budget proposal released by the White House would increase science funding and end austerity-driven budget cuts.
Working Together to Advance the Earth and Space Sciences
Authors: Finn Carol
Published: March 2015

Attendees at the American Geophysical Union’s 2014 Fall Meeting embodied the Union’s mission of “Earth and space science for the benefit of humanity.”
Virtual Programs Give Everyone Access to the 2014 Fall Meeting
Authors: Brown Virgil
Published: March 2015

Thousands of people across the world watched video recordings of the Fall Meeting’s Union lectures, named lectures, and oral presentations.
89 Geophysicists Honored at a Gala Tribute
Authors: Paredes Beth
Published: March 2015

Held on 17 December 2014, the American Geophysical Union’s Honors Tribute celebrated the breakthrough achievements, outstanding contributions, and service of select members.
Insulating state in tetralayers reveals an even–odd interaction effect in multilayer graphene
Authors: Grushina Anya L. , Ki Dong-Keun , Koshino Mikito , Nicolet Aurelien A. L. , Faugeras Clément , McCann Edward , Potemski Marek , Morpurgo Alberto F.
Published: March 2015

Close to charge neutrality, the electronic properties of graphene and its multilayers are sensitive to electron–electron interactions. In bilayers, for instance, interactions are predicted to open a gap between valence and conduction bands, turning the system into an insulator. In mono and (Bernal-stacked) trilayers, which remain conducting at low temperature, interactions do not have equally drastic consequences. It is expected that interaction effects become weaker for thicker multilayers, whose behaviour should converge to that of graphite. Here we show that this expectation does not correspond to reality by revealing the occurrence of an insulating state close to charge neutrality in Bernal-stacked tetralayer graphene. The phenomenology—incompatible with the behaviour expected from the single-particle band structure—resembles that observed in bilayers, but the insulating state in tetralayers is visible at higher temperature. We explain our findings, and the systematic even–odd effect of interactions in Bernal-stacked layers of different thickness that emerges from experiments, in terms of a generalization of the interaction-driven, symmetry-broken states proposed for bilayers.
High-resolution gene expression data from blastoderm embryos of the scuttle fly Megaselia abdita
Authors: Wotton Karl R , Jiménez-Guri Eva , Crombach Anton , Cicin-Sain Damjan , Jaeger Johannes
Published: March 2015

Gap genes are involved in segment determination during early development in dipteran insects (flies, midges, and mosquitoes). We carried out a systematic quantitative comparative analysis of the gap gene network across different dipteran species. Our work provides mechanistic insights into the evolution of this pattern-forming network. As a central component of our project, we created a high-resolution quantitative spatio-temporal data set of gap and maternal co-ordinate gene expression in the blastoderm embryo of the non-drosophilid scuttle fly, Megaselia abdita. Our data include expression patterns in both wild-type and RNAi-treated embryos. The data—covering 10 genes, 10 time points, and over 1,000 individual embryos—consist of original embryo images, quantified expression profiles, extracted positions of expression boundaries, and integrated expression patterns, plus metadata and intermediate processing steps. These data provide a valuable resource for researchers interested in the comparative study of gene regulatory networks and pattern formation, an essential step towards a more quantitative and mechanistic understanding of developmental evolution.
A reusable immobilization matrix for the biodegradation of phenol at 5000 mg/L
Authors: Li Najun , Jiang Jun , Chen Dongyun , Xu Qingfeng , Li Hua , Lu Jianmei
Published: March 2015

Bacteria-mediated degradation of toxins has been reported as a practical technique for the innocuous removal of toxic organic compounds from water. Specifically, immobilized and pre-acclimatized Pseudomonas putida has been shown to clear low levels of contaminants (less than 2000 mg/L) from wastewater, wherein the bacteria consumes toxic aromatic compounds as the only source of carbon and energy. Here we report the preparation of a high-capacity composite adsorbent as an immobilization matrix for pre-acclimatized P. putida that is capable of complete degradation of 5000 mg/L of phenol within 80 hours. The composite adsorbent, a n-Butyl acrylate (BA)-resin evenly coated on polyester fiber (PF), can quickly reduce the phenol concentration to a level that is suitable for the immobilized bacteria to start the biodegradation process. Furthermore, the composite adsorbent (PF-BA) is regenerated during the biodegradation process without any additional manipulations, therefore it is reusable. As a whole, we provide a general strategy for more efficient biodegradation for phenol, which can be generalized to other water-soluble toxic organics removal for waste water treatment.
WNT-1 inducible signaling pathway protein-1 enhances growth and tumorigenesis in human breast cancer
Authors: Chiang Kun-Chun , Yeh Chun-Nan , Chung Li-Chuan , Feng Tsui-Hsia , Sun Chi-Chin , Chen Miin-Fu , Jan Yi-Yin , Yeh Ta-Sen , Chen Shin-Cheh , Juang Horng-Heng
Published: March 2015

WNT1 inducible signaling pathway protein 1 (WISP1) plays a key role in many cellular functions in a highly tissue-specific manner; however the role of WISP1 in breast cancer is still poorly understood. Here, we demonstrate that WISP1 acts as an oncogene in human breast cancer. We demonstrated that human breast cancer tissues had higher WISP1 mRNA expression than normal breast tissues and that treatment of recombinant WISP1 enhanced breast cancer cell proliferation. Further, ectopic expression of WISP1 increased the growth of breast cancer cells in vitro and in vivo. WISP1 transfection also induced epithelial-mesenchymal-transition (EMT) in MCF-7 cells, leading to higher migration and invasion. During this EMT-inducing process, E-cadherin was repressed and N-cadherin, snail and β-catenin were upregulated. Filamentous actin (F-actin) remodeling and polarization were also observed after WISP1 transfection into MCF-7 cells. Moreover, forced overexpression of WISP1 blocked the expression of NDRG1, a breast cancer tumor suppressor gene. Our study provides novel evidence that WISP1-modulated NDRG1 gene expression is dependent on a DNA fragment (−128 to +46) located within the human NDRG1 promoter. Thus, we concluded that WISP1 is a human breast cancer oncogene and is a potential therapeutic target.
Crystal structure of Gib2, a signal-transducing protein scaffold associated with ribosomes in Cryptococcus neoformans
Authors: Ero Rya , Dimitrova Valya Tenusheva , Chen Yun , Bu Wenting , Feng Shu , Liu Tongbao , Wang Ping , Xue Chaoyang , Tan Suet Mien , Gao Yong-Gui
Published: March 2015

The atypical Gβ-like/RACK1 Gib2 protein promotes cAMP signalling that plays a central role in regulating the virulence of Cryptococcus neoformans. Gib2 contains a seven-bladed β transducin structure and is emerging as a scaffold protein interconnecting signalling pathways through interactions with various protein partners. Here, we present the crystal structure of Gib2 at a 2.2-Å resolution. The structure allows us to analyse the association between Gib2 and the ribosome, as well as to identify the Gib2 amino acid residues involved in ribosome binding. Our studies not only suggest that Gib2 has a role in protein translation but also present Gib2 as a physical link at the crossroads of various regulatory pathways important for the growth and virulence of C. neoformans.
The electronic structure of metal oxide/organo metal halide perovskite junctions in perovskite based solar cells
Authors: Dymshits Alex , Henning Alex , Segev Gideon , Rosenwaks Yossi , Etgar Lioz
Published: March 2015

Cross-sections of a hole-conductor-free CH3NH3PbI3 perovskite solar cell were characterized with Kelvin probe force microscopy. A depletion region width of about 45 nm was determined from the measured potential profiles at the interface between CH3NH3PbI3 and nanocrystalline TiO2, whereas a negligible depletion was measured at the CH3NH3PbI3/Al2O3 interface. A complete solar cell can be realized with the CH3NH3PbI3 that functions both as light harvester and hole conductor in combination with a metal oxide. The band diagrams were estimated from the measured potential profile at the interfaces and are critical findings for a better understanding and further improvement of perovskite based solar cells.
Disentangling the impacts of outcome valence and outcome frequency on the post-error slowing
Authors: Wang Lijun , Tang Dandan , Zhao Yuanfang , Hitchman Glenn , Wu Shanshan , Tan Jinfeng , Chen Antao
Published: March 2015

Post-error slowing (PES) reflects efficient outcome monitoring, manifested as slower reaction time after errors. Cognitive control account assumes that PES depends on error information, whereas orienting account posits that it depends on error frequency. This raises the question how the outcome valence and outcome frequency separably influence the generation of PES. To address this issue, we varied the probability of observation errors (50/50 and 20/80, correct/error) the “partner” committed by employing an observation-execution task and investigated the corresponding behavioral and neural effects. On each trial, participants first viewed the outcome of a flanker-run that was supposedly performed by a ‘partner’ and then performed a flanker-run themselves afterwards. We observed PES in the two error rate conditions. However, electroencephalographic data suggested error-related potentials (oERN and oPe) and rhythmic oscillation associated with attentional process (alpha band) were respectively sensitive to outcome valence and outcome frequency. Importantly, oERN amplitude was positively correlated with PES. Taken together, these findings support the assumption of the cognitive control account, suggesting that outcome valence and outcome frequency are both involved in PES. Moreover, the generation of PES is indexed by oERN, whereas the modulation of PES size could be reflected on the alpha band.
Use of TiO2 nanotube arrays as the adsorbents for preconcentration of triazine herbicides in environmental water samples prior to determination using high performance liquid chromatography
Authors: Zhou Qingxiang , Fang Zhi
Published: March 2015

A simple, sensitive and reliable method using ordered TiO2 nanotube arrays was developed for the determination of four triazine herbicides.
An improved dual-stage protocol to pre-concentrate mercury from airborne particles for precise isotopic measurement
Authors: Huang Qiang , Liu YuLong , Chen JiuBin , Feng XinBin , Huang WeiLin , Yuan ShengLiu , Cai HongMing , Fu XueWu
Published: March 2015

The Hg isotopic signature may provide insight into tracking the sources and pathways of both airborne particulate matter (PM) and particle-bound Hg (PHg) in the atmosphere.
A highly bioactive and biodegradable poly(glycerol sebacate)–silica glass hybrid elastomer with tailored mechanical properties for bone tissue regeneration
Authors: Zhao Xin , Wu Yaobin , Du Yuzhang , Chen Xiaofeng , Lei Bo , Xue Yumeng , Ma Peter X.
Published: March 2015

A highly bioactive and biodegradable PGS–Silica bioactive glass hybrid elastomer with tailored mechanical properties was developed for bone tissue regeneration application.
An entry to vinylcyclopropane through palladium-catalyzed intramolecular cyclopropanation of alkenes with unstabilized allylic tosylhydrazones
Authors: Yang Yang , Li Jinpeng , Du Biao , Yuan Changchun , Liu Bo , Qin Song
Published: March 2015

Intramolecular cyclopropanation of unstabilized allylic tosylhydrazones with different alkenes was developed in the presence of a Pd catalyst.
Rh-catalysed direct cyclisation of 1,4-naphthoquinone and 9,10-phenanthraquinone with alkyne: facile access to 1,8-dioxapyrenes and 1,12-dioxaperylenes as orange and red-emitting luminophores
Authors: Wang Jing , Qin Dekun , Lan Jingbo , Cheng Yangyang , Zhang Shuai , Guo Qiang , Wu Jie , Wu Di , You Jingsong
Published: March 2015

Rh-catalysed direct cyclisation of quinones with alkynes has been accomplished through C–H activation strategy.
Electrocatalytic water oxidation by CuII complexes with branched peptides
Authors: Pap József S. , Szyrwiel Łukasz , Srankó Dávid , Kerner Zsolt , Setner Bartosz , Szewczuk Zbigniew , Malinka Wiesław
Published: March 2015

Two CuII complexes with branched tetrapeptides undergo PCET and catalyse water oxidation, processes promoted by the presence of C-terminal histidine.
Synthesis of oxazolidine-2,4-diones by a tandem phosphorus-mediated carboxylative condensation–cyclization reaction using atmospheric carbon dioxide
Authors: Zhang Wen-Zhen , Xia Tian , Yang Xu-Tong , Lu Xiao-Bing
Published: March 2015

A novel access to oxazolidine-2,4-diones using atmospheric CO2and readily available substrates under mild and transition-metal-free conditions is developed.
Does thermal treatment merely make a H2O-saturated Nafion membrane lose its absorbed water at high temperature?
Authors: Feng Kai , Hou Lei , Tang Beibei , Wu Peiyi
Published: March 2015

Influences of thermal treatment on H2O-saturated Nafion microstructures are investigated by in situ FTIR, TGA, XRD and 2Dcos techniques.
Prospects and challenges of iron pyroelectrolysis in magnesium aluminosilicate melts near minimum liquidus temperature
Authors: Ferreira N. M. , Kovalevsky A. V. , Mikhalev S. M. , Costa F. M. , Frade J. R.
Published: March 2015

The work demonstrates high faradaic efficiency of the pyroelectrolysis process for iron extraction under electron-blocking conditions, and discusses the role and mechanisms of relevant parasitic electrochemical reactions.
Environmental and economic tradeoffs of using corn stover for liquid fuels and power production
Authors: Trivedi Parthsarathi , Malina Robert , Barrett Steven R. H.
Published: March 2015

Using agricultural residue biomass for electricity and heat production results in greater carbon dioxide emissions reductions than creating transportation biofuel.
Chromium deposition and poisoning of La0.8Sr0.2MnO3 oxygen electrodes of solid oxide electrolysis cells
Authors: Chen Kongfa , Hyodo Junji , Dodd Aaron , Ai Na , Ishihara Tatsumi , Jian Li , Jiang San Ping
Published: March 2015

The effect of the presence of an Fe–Cr alloy metallic interconnect on the performance and stability of La0.8Sr0.2MnO3 (LSM) oxygen electrodes is studied for the first time under solid oxide electrolysis cell (SOEC) operating conditions at 800 °C. The presence of the Fe–Cr interconnect accelerates the degradation and delamination processes of the LSM oxygen electrodes. The disintegration of LSM particles and the formation of nanoparticles at the electrode/electrolyte interface are much faster as compared to that in the absence of the interconnect. Cr deposition occurs in the bulk of the LSM oxygen electrode with a high intensity on the YSZ electrolyte surface and on the LSM electrode inner surface close to the electrode/electrolyte interface. SIMS, GI-XRD, EDS and XPS analyses clearly identify the deposition and formation of chromium oxides and strontium chromate on both the electrolyte surface and electrode inner surface. The anodic polarization promotes the surface segregation of SrO and depresses the generation of manganese species such as Mn2+. This is evidently supported by the observation of the deposition of SrCrO4, rather than (Cr,Mn)3O4 spinels as in the case under the operating conditions of solid oxide fuel cells. The present results demonstrate that the Cr deposition is essentially a chemical process, initiated by the nucleation and grain growth reaction between the gaseous Cr species and segregated SrO on LSM oxygen electrodes under SOEC operating conditions.
New efficient fused-ring spiro[benzoanthracene-fluorene] dopant materials for blue fluorescent organic light-emitting diodes
Authors: Cha Jae-Ryung , Lee Chil-Won , Gong Myoung-Seon
Published: March 2015

Novel fused-ring spirobenzoanthracene-fluorene blue dopants have been successfully designed and synthesized for the fluorescent sky-blue OLEDs using SBTF host and SBAF dopants.
Synthesis of 2,4-diarylsubstituted-pyridines through a Ru-catalyzed four component reaction
Authors: Bai Yang , Tang Lichang , Huang Huawen , Deng Guo-Jun
Published: March 2015

2,4-Diarylsubstituted pyridines were prepared from acetophenones, ammonium acetate and DMF under an oxygen atmosphere.
Concise asymmetric total synthesis of bruceolline J
Authors: Dethe Dattatraya H. , Kumar B Vijay
Published: March 2015

Concise biomimetic and asymmetric approach involving Sharpless asymmetric dihydroxylation and Lewis acid catalysed cyclopenta[b]annulation as key steps to synthesize (+)-bruceolline J.
Influence of matrix modulus on the mechanical and interfacial properties of carbon fiber filament wound composites
Authors: Zhang Qingjie , Liang Shengbiao , Sui Gang , Yang Xiaoping
Published: March 2015

High modulus resin matrix is proposed to be an essential prerequisite to carbon fiber filament wound composites with excellent mechanical and interfacial properties.
TBATB mediated debenzylative cross-coupling of aryl benzyl sulfides with electron rich compounds: synthesis of diaryl sulfides
Authors: Hazarika Sukanya , Gogoi Prasanta , Barman Pranjit
Published: March 2015

An efficient TBATB mediated debenzylative cross coupling of aryl benzyl sulfides with electron rich compounds provides diaryl sulfides in moderate to excellent yield.
Copper-catalyzed trifluoromethylation of organic zinc reagents with an electrophilic trifluoromethylating reagent
Authors: Wang Chang-Sheng , Wang Haoyang , Yao Cheng
Published: March 2015

Trifluoromethylation of aryl and alkyl zinc reagents under mild conditions was described.
The P-site A76 2′-OH acts as a peptidyl shuttle in a stepwise peptidyl transfer mechanism
Authors: Monajemi Hadieh , Mohd Zain Sharifuddin , Wan Abdullah Wan Ahmad Tajuddin
Published: March 2015

The P-site-A76-2′OH transfers the polypeptide chain to the A-site α-amine and A2451 facilitates this transfer by acting as proton shuttle.
Inhibition of the malate–aspartate shuttle in mouse pancreatic islets abolishes glucagon secretion without affecting insulin secretion
Authors: Stamenkovic Jelena A. , Andersson Lotta E. , Adriaenssens Alice E. , Bagge Annika , Sharoyko Vladimir V. , Gribble Fiona , Reimann Frank , Wollheim Claes B. , Mulder Hindrik , Spégel Peter
Published: March 2015

Altered secretion of insulin as well as glucagon has been implicated in the pathogenesis of Type 2 diabetes (T2D), but the mechanisms controlling glucagon secretion from α-cells largely remain unresolved. Therefore, we studied the regulation of glucagon secretion from αTC1-6 (αTC1 clone 6) cells and compared it with insulin release from INS-1 832/13 cells. We found that INS-1 832/13 and αTC1-6 cells respectively secreted insulin and glucagon concentration-dependently in response to glucose. In contrast, tight coupling of glycolytic and mitochondrial metabolism was observed only in INS-1 832/13 cells. Although glycolytic metabolism was similar in the two cell lines, TCA (tricarboxylic acid) cycle metabolism, respiration and ATP levels were less glucose-responsive in αTC1-6 cells. Inhibition of the malate–aspartate shuttle, using phenyl succinate (PhS), abolished glucose-provoked ATP production and hormone secretion from αTC1-6 but not INS-1 832/13 cells. Blocking the malate–aspartate shuttle increased levels of glycerol 3-phosphate only in INS-1 832/13 cells. Accordingly, relative expression of constituents in the glycerol phosphate shuttle compared with malate–aspartate shuttle was lower in αTC1-6 cells. Our data suggest that the glycerol phosphate shuttle augments the malate–aspartate shuttle in INS-1 832/13 but not αTC1-6 cells. These results were confirmed in mouse islets, where PhS abrogated secretion of glucagon but not insulin. Furthermore, expression of the rate-limiting enzyme of the glycerol phosphate shuttle was higher in sorted primary β- than in α-cells. Thus, suppressed glycerol phosphate shuttle activity in the α-cell may prevent a high rate of glycolysis and consequently glucagon secretion in response to glucose. Accordingly, pyruvate- and lactate-elicited glucagon secretion remains unaffected since their signalling is independent of mitochondrial shuttles.
Electron transfer by human wild-type and A287P mutant P450 oxidoreductase assessed by transient kinetics: functional basis of P450 oxidoreductase deficiency
Authors: Jin Yi , Chen Mo , Penning Trevor M. , Miller Walter L.
Published: March 2015

Cytochrome P450 oxidoreductase (POR) is a 2-flavin protein that transfers electrons from NADPH via its FAD and FMN moieties to all microsomal cytochrome P450 enzymes, including steroidogenic and drug-metabolizing P450s. Defects in the POR gene can cause POR deficiency (PORD), manifested clinically by disordered steroidogenesis, genital anomalies and skeletal malformations. We examined the POR mutant A287P, which is the most frequent cause of PORD in patients of European ancestry and partially disrupts most P450 activities in vitro. Flavin content analysis showed that A287P is deficient in FAD and FMN binding, although the mutation site is distant from the binding sites of both flavins. Externally added flavin partially restored the cytochrome c reductase activity of A287P, suggesting that flavin therapy may be useful for this frequent form of PORD. Transient kinetic dissection of the reaction of POR with NADPH and the reduction in cytochrome c by POR using stopped-flow techniques revealed defects in individual electron transfer steps mediated by A287P. A287P had impaired ability to accept electrons from NADPH, but was capable of a fast FMN → cytochrome c electron donation reaction. Thus the reduced rates of P450 activities with A287P may be due to deficient flavin and impaired electron transfer from NADPH.
Competition and Strategic Dilemmas in the Telecommunications Industry: Making the Triple Play
Authors: Dekleva Sasha , Zadony Markian
Published: March 2015

Southern Bell Corporation, now AT&T, decided to upgrade its existing networks by extending its optical fiber network only to the neighborhood nodes and use existing telephone twisted pair copper wires to connect nodes with households. Leaders of Verizon Communications, on the other hand, decided to extend their optical fiber network all the way to homes at much higher cost. The choice of which of the two approaches was a better business decision is the main dilemma in the case. The network upgrades were necessary to keep telecommunication operators competitive with cable television companies, which after they upgraded their networks started offering the ‘triple play,’ a combination of video programming, telephone, and Internet services. The case reviews the history of telecommunication and cable industries in the United States, which leads to exploration of the key issues including (i) whether, and if so how competition in the telecommunication industry is even possible, (ii) how much bandwidth do we really need, and (iii) what is the effect of various compression techniques, convergence of digital technologies, and what other countries are doing. The case (describing the state of the industry at about the start of 2011) addresses an issue affecting all of us as we decide what services to select for our entertainment and communication needs.
Magnetic nanoparticles with high specific absorption rate of electromagnetic energy at low field strength for hyperthermia therapy
Authors: Shubitidze Fridon , Kekalo Katsiaryna , Stigliano Robert , Baker Ian
Published: March 2015

Magnetic nanoparticles (MNPs), referred to as the Dartmouth MNPs, which exhibit high specific absorption rate at low applied field strength have been developed for hyperthermia therapy applications. The MNPs consist of small (2–5 nm) single crystals of gamma-Fe2O3 with saccharide chains implanted in their crystalline structure, forming 20–40 nm flower-like aggregates with a hydrodynamic diameter of 110–120 nm. The MNPs form stable (>12 months) colloidal solutions in water and exhibit no hysteresis under an applied quasistatic magnetic field, and produce a significant amount of heat at field strengths as low as 100 Oe at 99–164 kHz. The MNP heating mechanisms under an alternating magnetic field (AMF) are discussed and analyzed quantitatively based on (a) the calculated multi-scale MNP interactions obtained using a three dimensional numerical model called the method of auxiliary sources, (b) measured MNP frequency spectra, and (c) quantified MNP friction losses based on magneto-viscous theory. The frequency responses and hysteresis curves of the Dartmouth MNPs are measured and compared to the modeled data. The specific absorption rate of the particles is measured at various AMF strengths and frequencies, and compared to commercially available MNPs. The comparisons demonstrate the superior heating properties of the Dartmouth MNPs at low field strengths (<250 Oe). This may extend MNP hyperthermia therapy to deeper tumors that were previously non-viable targets, potentially enabling the treatment of some of the most difficult cancers, such as pancreatic and rectal cancers, without damaging normal tissue.
Intersystem-crossing and phosphorescence rates in fac-IrIII(ppy)3: A theoretical study involving multi-reference configuration interaction wavefunctions
Authors: Kleinschmidt Martin , van Wüllen Christoph , Marian Christel M.
Published: March 2015

We have employed combined density functional theory and multi-reference configuration interaction methods including spin–orbit coupling (SOC) effects to investigate the photophysics of the green phosphorescent emitter fac-tris-(2-phenylpyridine)iridium (fac-Ir(ppy)3). A critical evaluation of our quantum chemical approaches shows that a perturbational treatment of SOC is the method of choice for computing the UV/Vis spectrum of this heavy transition metal complex while multi-reference spin–orbit configuration interaction is preferable for calculating the phosphorescence rates. The particular choice of the spin–orbit interaction operator is found to be of minor importance. Intersystem crossing (ISC) rates have been determined by Fourier transformation of the time correlation function of the transition including Dushinsky rotations. In the electronic ground state, fac-Ir(ppy)3 is C3 symmetric. The calculated UV/Vis spectrum is in excellent agreement with experiment. The effect of SOC is particularly pronounced for the metal-to-ligand charge transfer (MLCT) band in the visible region of the absorption spectrum which does not only extend its spectral onset towards longer wavelengths but also experiences a blue shift of its maximum. Pseudo-Jahn-Teller interaction leads to asymmetric coordinate displacements in the lowest MLCT states. Substantial electronic SOC and a small energy gap make ISC an ultrafast process in fac-Ir(ppy)3. For the S1↝T1 non-radiative transition, we compute a rate constant of kISC = 6.9 × 1012 s−1 which exceeds the rate constant of radiative decay to the electronic ground state by more than six orders of magnitude, in agreement with the experimental observation of a subpicosecond ISC process and a triplet quantum yield close to unity. As a consequence of the geometric distortion in the T1 state, the T1 → S0 transition densities are localized on one of the phenylpyridyl moieties. In our best quantum chemical model, we obtain phosphorescence decay times of 264 μs, 13 μs, and 0.9 μs, respectively, for the T1,I, T1,II, and T1,III fine-structure levels in dichloromethane (DCM) solution. In addition to reproducing the correct orders of magnitude for the individual phosphorescence emission probabilities, our theoretical study gives insight into the underlying mechanisms. In terms of intensity borrowing from spin-allowed transitions, the low emission probability of the T1,I substate is caused by the mutual cancellation of contributions from several singlet states to the total transition dipole moment. Their contributions do not cancel but add up in case of the much faster T1,III → S0 emission while the T1,II → S0 emission is dominated by intensity borrowing from a single spin-allowed process, i.e., the S2 → S0 transition.
Electron dynamics upon ionization: Control of the timescale through chemical substitution and effect of nuclear motion
Authors: Vacher Morgane , Mendive-Tapia David , Bearpark Michael J. , Robb Michael A.
Published: March 2015

Photoionization can generate a non-stationary electronic state, which leads to coupled electron-nuclear dynamics in molecules. In this article, we choose benzene cation as a prototype because vertical ionization of the neutral species leads to a Jahn-Teller degeneracy between ground and first excited states of the cation. Starting with equal populations of ground and first excited states, there is no electron dynamics in this case. However, if we add methyl substituents that break symmetry but do not radically alter the electronic structure, we see charge migration: oscillations in the spin density that we can correlate with particular localized electronic structures, with a period depending on the gap between the states initially populated. We have also investigated the effect of nuclear motion on electron dynamics using a complete active space self-consistent field (CASSCF) implementation of the Ehrenfest method, most previous theoretical studies of electron dynamics having been carried out with fixed nuclei. In toluene cation for instance, simulations where the nuclei are allowed to move show significant differences in the electron dynamics after 3 fs, compared to simulations with fixed nuclei.