bluuebunny/crossref_metadata_2025 huggingface dataset:
Australian immigration detention and the silencing of practitioners
Authors: Pearman April , Olinga-Shannon Stephanie
Published: February 2018

In recent years, the Australian Government has framed the arrival of asylum seekers by boat as a national security risk and the policy of stopping ‘unauthorised maritime arrivals’ has been used extensively byvarious political parties in their election campaign platforms (Phillips, 2017). Click on the pdf to read more.
Landscape connectivity among remnant populations of guanaco (Lama guanicoe Müller, 1776) in an arid region of Chile impacted by global change
Authors: Espinosa Herazo Mara Ines , Gouin Nicolas , Squeo Porcile Francisco Antonio , López Aspe David , Bertin Angéline
Published: February 2018

Connectivity between populations plays a key role in the long-term persistence of species in fragmented habitats. It is an issue of concern for the preservation of biodiversity in drylands since landscapes in water limited environments are characterized by low habitat cover, high habitat fragmentation and harsh matrices, and are being rapidly degraded at the global scale. In this study, we modelled landscape connectivity between the 11 remnant coastal and Andean populations of the guanaco Lama guanicoe, an emblematic herbivore indigenous to South America, in Chile's arid Norte Chico. We first produced a habitat surface model to derive a regional surface resistance map; and we then used circuit theory to map functional connectivity, investigate the degree of isolation of the populations, and identify those that most contribute to the network patch connectivity. Predicted suitable habitat for L. guanicoe represented about 25% of the study region (i.e. 29,173 km2), and was heterogeneously distributed along a continuous stretch along the Andes, and discontinuous patches along the coast. As a result, we found that high connectivity current flows in the mid and high Andes formed a wide continuous connectivity corridor enabling connectivity between all the high Andean populations. Coastal populations, in contrast, were predicted to be more isolated. They only connect to medium and high altitude populations, and for two of them, animal movement was linked to the effectiveness of wildlife crossings. Based on the degree of connectivity, population size, and local threats, the coastal and the northernmost populations were identified as being most vulnerable, while the Andean populations appeared to be least at risk, even when located near areas of mining activity. Collectively, our results suggest that functional connectivity is an issue of concern for L. guanicoe in Chile’s Norte Chico, and that future conservation and management plans should adopt a landscape strategy aiming at conserving the functional connectivity between the coastal and Andean populations, and at protecting the habitat patches likely to act as stepping stones within the connectivity network.
The Role of Crustal Strength in Controlling Magmatism and Melt Chemistry During Rifting and Breakup
Authors: Armitage John J. , Petersen Kenni D. , Pérez‐Gussinyé Marta
Published: February 2018

The strength of the crust has a strong impact on the evolution of continental extension and breakup. Strong crust may promote focused narrow rifting, while wide rifting might be due to a weaker crustal architecture. The strength of the crust also influences deeper processes within the asthenosphere. To quantitatively test the implications of crustal strength on the evolution of continental rift zones, we developed a 2‐D numerical model of lithosphere extension that can predict the rare Earth element (REE) chemistry of erupted lava. We find that a difference in crustal strength leads to a different rate of depletion in light elements relative to heavy elements. By comparing the model predictions to rock samples from the Basin and Range, USA, we can demonstrate that slow extension of a weak continental crust can explain the observed depletion in melt chemistry. The same comparison for the Main Ethiopian Rift suggests that magmatism within this narrow rift zone can be explained by the localization of strain caused by a strong lower crust. We demonstrate that the slow extension of a strong lower crust above a mantle of potential temperature of
can fit the observed REE trends and the upper mantle seismic velocity for the Main Ethiopian Rift. The thermo‐mechanical model implies that melt composition could provide quantitative information on the style of breakup and the initial strength of the continental crust.
Radiation Belt “Dropouts” and Drift‐Bounce Resonances in Broadband Electromagnetic Waves
Authors: Chaston C. C. , Bonnell J. W. , Wygant J. R. , Reeves G. D. , Baker D. N. , Melrose D. B.
Published: February 2018

Observations during the main phase of geomagnetic storms reveal an anticorrelation between the occurrence of broadband low‐frequency electromagnetic waves and outer radiation belt electron flux. We show that the drift‐bounce motion of electrons in the magnetic field of these waves leads to rapid electron transport. For observed spectral energy densities it is demonstrated that the wave magnetic field can drive radial diffusion via drift‐bounce resonance on time scales less than a drift orbit. This process may provide outward transport sufficient to account for electron “dropouts” during storm main phase and more generally modulate the outer radiation belt during geomagnetic storms.
Incoherent Scatter Spectra Based On Monte Carlo Simulations of Ion Velocity Distributions Under Strong Ion Frictional Heating
Authors: Goodwin L. V. , St.‐Maurice J.‐P. , Akbari H. , Spiteri R. J.
Published: February 2018

Under strong electric field conditions often found at high latitudes, the ion velocity distribution of the weakly ionized F region plasma can differ enough from a Maxwellian shape to substantially change incoherent scatter (IS) spectra and thus the analysis of those spectra. With the goal to provide a quantitative and reliable description of the IS spectra, this study directly uses for the first time an advanced Monte Carlo calculation of the ion velocity distribution to derive IS spectra for a range of electric fields and aspect angles. For most cases the spectra associated with NO+ maintains a shape that closely resembles that of a spectrum derived from a Maxwellian distribution with the same line‐of‐sight ion temperature as the equivalent Monte Carlo simulated distribution. This study also fully characterizes the spectral shape as well as the ion temperature and its anisotropy for two different models of the resonant charge exchange between O+ and O. It confirms that the distortions from the Maxwellian shape can be substantial for this particular interaction. The distortions are also such that along the magnetic field direction, the extracted apparent electron temperature is always greater than the real temperature. This work also includes a determination of the stability of the plasma against magnetic field‐aligned electrostatic instabilities. It is found that the NO+ distribution is always stable, whereas the O+ distribution may or may not be stable, depending on the model chosen for the resonant charge exchange cross section in collisions with the background atomic oxygen gas.
Reliability and Validity of Three Versions of the Brief Fear of Negative Evaluation Scale in Patients With Systemic Sclerosis: A Scleroderma Patient‐Centered Intervention Network Cohort Study
Authors: Fox Rina S. , Kwakkenbos Linda , Carrier Marie‐Eve , Mills Sarah D. , Gholizadeh Shadi , Jewett Lisa R. , Roesch Scott C. , Merz Erin L. , Assassi Shervin , Furst Daniel E. , Gottesman Karen , Mayes Maureen D. , Thombs Brett D. , Malcarne Vanessa L. ,   and the SPIN Investigators
Published: February 2018

Objective

Fear of negative evaluation is a common concern among individuals with visible differences but has received limited attention in systemic sclerosis (SSc), which can involve substantial changes to appearance. The Brief Fear of Negative Evaluation Scale (BFNE) was specifically designed to evaluate fear of negative evaluation. There are currently 3 versions of the BFNE with strong demonstrated measurement properties: two 8‐item versions (BFNE‐S, BFNE‐8) and one 12‐item version (BFNE‐II). The present study evaluated these versions in SSc, and identified the most appropriate version for use among SSc patients.

Methods

Participants were 1,010 patients with SSc enrolled in the Scleroderma Patient‐Centered Intervention Network cohort. Multiple group confirmatory factor analysis, Cronbach's alpha, and Pearson's product‐moment correlations were used to evaluate structural validity, internal consistency reliability, and convergent and divergent validity, respectively.

Results

Confirmatory factor analysis demonstrated that 1‐factor models fit acceptably well for the 12‐item BFNE‐II, the 8‐item BFNE‐S, and the 8‐item BFNE‐8. Additionally, all Cronbach's alphas demonstrated excellent internal consistency reliability (BFNE‐II = 0.98, BFNE‐S = 0.97, BFNE‐8 = 0.96), and all versions had comparable associations with measures of social anxiety, body‐related attitudes, depression, age, and education.

Conclusion

Psychometric support was found for all 3 versions of the BFNE, although the longer 12‐item BFNE‐II did not improve measurement compared to the shorter 8‐item versions (BFNE‐S and BFNE‐8). Of these 2, the BFNE‐S has been more widely studied, with strong validity data in a greater number of populations. Therefore, the BFNE‐S is recommended to assess fear of negative evaluation among patients with SSc.
High‐Cycle Fatigue Behavior and Damage Mechanism of Multiphase Al–Si Piston Alloy at Room and Elevated Temperatures
Authors: Liu Haiquan , Pang Jianchao , Wang Meng , Li Shouxin , Zhang Zhefeng
Published: February 2018

Microstructure evolution, tensile properties, fatigue crack initiation and propagation behaviors, and corresponding damage mechanisms of a multiphase cast Al–Si alloy used for pistons at room temperature (RT), 350 and 425 °C are investigated. The results show that tensile and fatigue strengths decrease with the increase of temperature. Casting defects such as pores and oxide films are the most preferential sites for fatigue initiation at all the temperatures. The preferential propagation path for fatigue crack is mainly through the Al matrix and second phases at room temperature, through Al matrix at 350 °C, and along grain boundary and phase/matrix interface at 425 °C. This may be attributed to the reduction of strengths of matrix and phase/matrix interface at elevated temperatures. Relationship between fatigue strength and defect size is also discussed using critical stress intensity factor and probability distribution of defect size.
Enantioselective Cyanosilylation of Alkynyl Ketones Catalyzed by Combined Systems Consisting of Chiral Ruthenium(II) Complex and Lithium Phenoxide
Authors: Ohkuma Takeshi , Kurono Nobuhito , Sakaguchi Yusuke , Yamauchi Kohei , Yurino Taiga
Published: February 2018

Asymmetric cyanosilylation of alkynyl ketones with the catalyst systems consisting of amino acid/2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl (BINAP)/ruthenium(II) complex and lithium phenoxide (Ru⋅Li cat.) was studied. The reaction was conducted in tert‐butyl methyl ether (TBME) at −78 °C with a substrate‐to‐catalyst molar ratio (S/C) as high as 2000. A series of simple and functionalized ketones was converted into the alkynyl tertiary cyanohydrin derivatives in up to 99% ee. Appropriate selection of an amino‐acid ligand of the catalyst according to the substrate structure was crucially important to achieve high enantioselectivity and a wide scope of substrates. Transformation of the chiral cyanohydrin product into a functionalized lactone was also examined.

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Radical Alkyne peri‐Annulation Reactions for the Synthesis of Functionalized Phenalenes, Benzanthrenes, and Olympicene
Authors: Tsvetkov Nikolay P. , Gonzalez‐Rodriguez Edgar , Hughes Audrey , dos Passos Gomes Gabriel , White Frankie D. , Kuriakose Febin , Alabugin Igor V.
Published: February 2018

Radical cyclization reactions at a peri position were used for the synthesis of polyaromatic compounds. Depending on the choice of reaction conditions and substrate, this flexible approach led to Bu3Sn‐substituted phenalene, benzanthrene, and olympicene derivatives. Subsequent reactions with electrophiles provided synthetic access to previously inaccessible functionalized polyaromatic compounds.
Predicting the Helical Sense of Poly(phenylacetylene)s from their Electron Circular Dichroism Spectra
Authors: Fernández Berta , Rodríguez Rafael , Rizzo Antonio , Quiñoá Emilio , Riguera Ricardo , Freire Félix
Published: February 2018

The calculated ECD spectrum (time‐dependent density functional theory TD‐DFT) for small oligomers of polyphenylacetylenes (PPAs) show a very good match with the experimental spectra of the PPA polymers, particularly with the first Cotton band associated to the helical sense of the internal polyenic backbone. This has been proven with a series of PPAs representative of cis‐cisoidal, cis‐transoidal, compressed and stretched polyene backbones, with identical or opposite internal/external rotational senses and allows the prediction of the helical sense of the internal helix of a PPA directly from its CD spectra.
Evaluation of the Catalytic Relevance of the CO‐Bound States of V‐Nitrogenase
Authors: Lee Chi Chung , Wilcoxen Jarett , Hiller Caleb J. , Britt R. David , Hu Yilin
Published: February 2018

Binding and activation of CO by nitrogenase is a topic of interest because CO is isoelectronic to N2, the physiological substrate of this enzyme. The catalytic relevance of one‐ and multi‐CO‐bound states (the lo‐CO and hi‐CO states) of V‐nitrogenase to C−C coupling and N2 reduction was examined. Enzymatic and spectroscopic studies demonstrate that the multiple CO moieties in the hi‐CO state cannot be coupled as they are, suggesting that C−C coupling requires further activation and/or reduction of the bound CO entity. Moreover, these studies reveal an interesting correlation between decreased activity of N2 reduction and increased population of the lo‐CO state, pointing to the catalytic relevance of the belt Fe atoms that are bridged by the single CO moiety in the lo‐CO state. Together, these results provide a useful framework for gaining insights into the nitrogenase‐catalyzed reaction via further exploration of the utility of the lo‐CO conformation of V‐nitrogenase.
Toward Thiophene‐Annulated Graphene Nanoribbons
Authors: Miao Dandan , Daigle Maxime , Lucotti Andrea , Boismenu‐Lavoie Joël , Tommasini Matteo , Morin Jean‐François
Published: February 2018

Narrow thiophene‐edged graphene nanoribbons (GNRs) were prepared from polychlorinated thiophene‐containing poly(p‐phenylene)s using the photochemical, metal‐free cyclodehydrochlorination (CDHC) reaction. 1H NMR and Raman spectroscopy confirmed the structures of the GNRs. The regioselectivity of the CDHC reaction allows the preparation of both laterally symmetrical and unsymmetrical GNRs and, consequently, the modulation of their optical and electronic properties.
Water‐Assisted Size and Shape Control of CsPbBr3 Perovskite Nanocrystals
Authors: Zhang Xiaoyu , Bai Xue , Wu Hua , Zhang Xiangtong , Sun Chun , Zhang Yu , Zhang Wei , Zheng Weitao , Yu William W. , Rogach Andrey L.
Published: February 2018

Lead‐halide perovskites are well known to decompose rapidly when exposed to polar solvents, such as water. Contrary to this common‐place observation, we have found that through introducing a suitable minor amount of water into the reaction mixture, we can synthesize stable CsPbBr3 nanocrystals. The size and the crystallinity, and as a result the band gap tunability of the strongly emitting CsPbBr3 nanocrystals correlate with the water content. Suitable amounts of water change the crystallization environment, inducing the formation of differently shaped perovskites, namely spherical NCs, rectangular nanoplatelets, or nanowires. Bright CsPbBr3 nanocrystals with the photoluminescence quantum yield reaching 90 % were employed for fabrication of inverted hybrid inorganic/organic light‐emitting devices, with the peak luminance of 4428 cd m−2 and external quantum yield of 1.7 %.
Development of microsatellite markers for the wind cave–associated shrub Lonicera alpigena subsp. glehnii (Caprifoliaceae)
Authors: Miyazaki Taisuke , Kimura Takuma , Kamata Kentaro , Maki Masayuki
Published: February 2018

Premise of the Study

Microsatellite markers were developed for the wind cave–associated shrub Lonicera alpigena subsp. glehnii to conduct phylogeographic studies on the species.

Methods and Results

Based on the sequence data obtained by 454 sequencing, a total of 81 primer pairs were designed and 18 successfully amplified the microsatellite regions. These markers were highly variable (i.e., average number of alleles per locus = 6.2 [range = 2–15]; average expected heterozygosity per locus = 0.489 [range = 0.149–0.729]). Cross‐species amplification of the primers was tested in 10 congeneric taxa (L. caerulea var. emphyllocalyx, L. chamissoi, L. chrysantha, L. gracilipes var. glandulosa, L. japonica, L. kurobushiensis, L. morrowii, L. ramosissima, L. sachalinensis, and L. strophiophora), and six to 11 primers amplified the microsatellite markers.

Conclusions

The microsatellite markers developed in this study will be useful for phylogeographic studies and conservation genetics of L. alpigena subsp. glehnii as well as congeneric species.
Characterization and transferability of microsatellites for Gentiana lawrencei var. farreri (Gentianaceae)
Authors: Sun Shan‐Shan , Fu Peng‐Cheng , Cheng Yan‐Wei , Zhou Xiao‐Jun , Han Jian‐Min
Published: February 2018

Premise of the Study

Microsatellite markers were developed for a medicinal herb, Gentiana lawrencei var. farreri (Gentianaceae), for the future assessment of population genetic structure and potential hybridization events with related taxa.

Methods and Results

Using the 454 FLX+ sequencing platform, we obtained 81,717 clean reads with an average length of 291 bp. A total of 3031 primer pairs were designed, and 96 were selected for validation. A set of 20 fluorescently labeled primer pairs was further selected and screened for polymorphisms in three G. lawrencei var. farreri populations and one G. veitchiorum population. Among the four populations, the average number of alleles per locus was 15.2. Finally, a set of 17 unlinked loci were determined to be in Hardy–Weinberg equilibrium after two linked loci were removed.

Conclusions

The identified simple sequence repeat markers will be useful for genetic diversity and evolution studies in G. lawrencei var. farreri and related taxa.
Long‐Term Safety and Efficacy of Belimumab in Patients With Systemic Lupus Erythematosus
Authors: Furie Richard A. , Wallace Daniel J. , Aranow Cynthia , Fettiplace James , Wilson Barbara , Mistry Prafull , Roth David A. , Gordon David
Published: February 2018

Objective

We undertook this US multicenter continuation study (GlaxoSmithKline study BEL112233; ClinicalTrials.gov identifier: NCT00724867) to assess long‐term safety and efficacy of belimumab in patients with systemic lupus erythematosus (SLE) who completed the Study of Belimumab in Subjects with SLE 76‐week trial (ClinicalTrials.gov identifier: NCT00410384).

Methods

Patients continued to receive the same belimumab dose plus standard therapy; patients previously receiving placebo received 10 mg/kg belimumab. The primary outcome measure was long‐term safety of belimumab (frequency of adverse events [AEs] and damage assessed using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index [SDI], evaluated every 48 weeks [1 study year]). Other assessments included the SLE Responder Index (SRI), flare rates (using the modified SLE Flare Index [SFI]), prednisone use, and B cell levels.

Results

Of 268 patients, 140 completed the study and 128 withdrew. The mean ± SD score on the Safety of Estrogens in Lupus Erythematosus National Assessment version of the SLE Disease Activity Index (SELENA–SLEDAI) at baseline was 7.8 ± 3.86. The mean ± SD SDI score increased by 0.4 ± 0.68 from its value at baseline (1.2 ± 1.51). The overall incidence of treatment‐related and serious AEs remained stable or declined through study year 7. An SRI response was achieved by 41.9% and 75.6% of patients at the study year 1 and study year 7 midpoints, respectively. At the study year 7 midpoint, relative to baseline, 78.2% had achieved a ≥4‐point reduction in the SELENA–SLEDAI score, 98.4% had no new British Isles Lupus Assessment Group (BILAG) A organ domain score and no more than 1 new BILAG B organ domain score, 93.7% had no worsening in the physician's global assessment of disease activity, 20.6% had experienced ≥1 severe SFI flare, the mean decrease in prednisone dose was 31.4%, and the median change in CD20+ B cell numbers was −83.2%.

Conclusion

These long‐term exposure results confirm the previously observed safety and efficacy profiles of belimumab in patients with SLE.
Bedarfsplanung und Grundlagenermittlung für WU‐Betonbauwerke
Authors: Bastert Heinrich , Fingerloos Frank , Kiltz Denis
Published: February 2018

Bei wasserundurchlässigen Bauwerken aus Beton, sog. WU‐Betonbauwerken, übernimmt die Betonkonstruktion neben der tragenden auch die abdichtende Funktion gegenüber einer Feuchtebeanspruchung von außen. Die WU‐Wanne als im Erdreich eingebettetes wasserundurchlässiges Bauwerk aus Beton hat sich – nicht zuletzt durch Richtlinien, Merkblätter und zahlreiche Fachveröffentlichungen – als bewährte Bauweise etabliert. Daneben haben sich in den letzten Jahren WU‐Dächer als weitere mögliche wasserundurchlässige Betonbauteile immer mehr durchgesetzt.

WU‐Betonbauwerke sind komplexe Baukonstruktionen, die eine enge Abstimmung zwischen den Bauherrenwünschen, der Planung und der Bauausführung erfordern. Hieraus ergibt sich, dass bereits bei der Konzeption von WU‐Betonbauwerken die Anforderungen des Bauherrn berücksichtigt werden müssen. Zur systematischen Erfassung dieser Anforderungen bietet sich ein methodisches Vorgehen im Rahmen einer Bedarfsplanung für WU‐Betonbauwerke an, die sich darüber hinaus zur umfassenden Beratung des Bauherrn und zur anschließenden Dokumentation der Planungsziele auf Basis definierter Bauherrenwünsche eignet.
Toward sustainable consumption: Investigating the determinants of green buying behaviour of Indian consumers
Authors: Jaiswal Deepak , Singh Bhagwan
Published: February 2018

Green buying behaviour can stimulate firms and society in the pursuit of sustainability while balancing the demand and supply side of the business cycle with addressing the ecological and social benefits. The objective of this paper is to understand and test the integrative model of green buying behaviour in the Indian and Asian context of sustainable consumption. The model is tested by applying structural equation modeling of path analysis using the total of 410 valid responses. The data were collected from Uttar Pradesh (India) through a structured questionnaire using the purposive convenient sampling. The results validate that “green purchase behaviour” is significantly determined by “green purchase intention,” which in turn significantly and positively influenced by “attitude towards green products.” The results also revealed that the measure of “environmental concern” and “perceived consumer effectiveness” were found to be positive and significant predictor of attitude towards green products, however, “perceived environmental knowledge” was not significantly related to attitude towards green products and perceived consumer effectiveness in the model. The discussion and implications are manifested towards sustainable consumption in the context of emerging target markets.
Green supply chain management and financial performance: The mediating roles of operational and environmental performance
Authors: Feng Mengying , Yu Wantao , Wang Xingyu , Wong Chee Yew , Xu Maozeng , Xiao Zhi
Published: February 2018

This study investigates the mediating effects of environmental and operational performance on the relationship between green supply chain management (GSCM) and financial performance. The proposed relationships are analyzed using survey data from a sample of 126 automobile manufacturers in China. The results suggest that GSCM as an integral supply chain strategy is significantly and positively associated with both environmental and operational performance, which then indirectly leads to improved financial performance. The results indicate the possible complementarity effects between various internal and external GSCM practices.
Perforations and how to manage: The coronary interventionalist and peripheral interventionalist working together for a solution
Authors: Heuser Richard R.
Published: February 2018

Key Points

Perforations can occur in both peripheral and coronary interventional procedures potentially resulting in severe morbidity

A readily available therapeutic option to treat perforations should be present in every cath lab that does coronary and peripheral procedures

The use of a coagulated thrombus injection can be an effective treatment option, but if a major vessel is affected that must remain patent, one viable option is to administer the patients’ own clotted blood to recanalize the vessel without permanent sequelae
Heparin use for diagnostic cardiac catheterization with a radial artery approach: An international survey of practice patterns
Authors: Bossard Matthias , Lavi Shahar , Rao Sunil V. , Cohen David J. , Cantor Warren J. , Bainey Kevin R. , Valettas Nicholas , Jolly Sanjit S. , Mehta Shamir R.
Published: February 2018

Objectives

We aimed to describe global practice patterns of unfractionated heparin (UFH) use for diagnostic transradial cardiac catheterization.

Background

The use of the radial artery approach for cardiac catheterization is increasing globally. Limited contemporary data exist to support the use or optimal dosing of UFH to prevent radial artery occlusion (RAO) and other thromboembolic complications.

Methods

We performed a web‐based international survey of 450 interventional cardiologists from 34 countries. We collected information regarding the experience and use of UFH for diagnostic transradial cardiac catheterization.

Results

The survey was conducted between June and July 2016 and was completed by 227 (50.4%) interventional cardiologists. Overall, 83.3% performed >75% of their coronary angiograms via a radial approach, with the plurality (41.9%) having 10–20 years of clinical experience. Of all respondents, 7.5% did not use UFH for routine diagnostic transradial heart catheterization. Of the 92.5% who did use UFH, it was preferentially administered intra‐arterially by 60% and intravenously by 40%. The majority (62.6%) of interventionalists used a fixed UFH dose with 5,000 IU being the most common dose (used in 48%). For those using a weight‐based UFH (50 IU/kg) dosing regimen for diagnostic procedures (36.1%), the administered UFH dose ranged from 2,000 up to 10,000 IU.

Conclusions

Despite the lack of firm evidence, the majority of interventional cardiologists who participated in the survey use UFH to prevent RAO for diagnostic transradial coronary angiography. However, there exist large practice disparities with regards to dose and route of administration. Given this knowledge gap, a dedicated randomized trial is warranted.
Cost‐Effective Palladium‐Doped Cu Bimetallic Materials to Tune Selectivity and Activity by using Doped Atom Ensembles as Active Sites for Efficient Removal of Acetylene from Ethylene
Authors: Zhang Riguang , Zhao Bo , Ling Lixia , Wang Anjie , Russell Christopher K. , Wang Baojun , Fan Maohong
Published: February 2018

The catalytic activity and selectivity of cost‐effective noble‐metal‐doped common metal materials strongly depend on the doped atom ensemble in specific arrangements to provide active sites. In this study, aiming at insight into the doped atom ensembles as active sites for tuning the selectivity and activity towards the target reaction, different doped noble metal Pd atom ensembles for cost‐effective Pd‐doped Cu catalysts act as active sites to investigate the activity and selectivity towards the efficient removal of acetylene from ethylene by using density functional theory calculations. The results show that an ensemble composed of one surface and its joint sublayer Pd atoms in the Cu catalyst as active sites enhance both the selectivity and activity of C2H4 formation caused by adjusting the catalyst surface electronic structure. Moreover, the surface d‐band center of the Pd‐doped Cu catalyst can act as an effective “descriptor” for the rapid screening of catalytic activity in the design of improved catalysts with the noble‐metal‐doped common metal. Further, the ensemble composed of one surface and its joint sublayer doped Pd atoms as active sites in the cost‐effective Pd‐doped Cu bimetallic catalysts is an efficient approach to finely tune the activity and selectivity towards the efficient removal of acetylene from ethylene.
Conserved Histidine Adjacent to the Proximal Cluster Tunes the Anaerobic Reductive Activation of Escherichia coli Membrane‐Bound [NiFe] Hydrogenase‐1
Authors: Flanagan Lindsey A. , Chidwick Harriet S. , Walton Julia , Moir James W. B. , Parkin Alison
Published: February 2018

[NiFe] hydrogenases are electrocatalysts that oxidize H2 at a rapid rate without the need for precious metals. All membrane‐bound [NiFe] hydrogenases (MBH) possess a histidine residue that points to the electron‐transfer iron sulfur cluster closest (“proximal”) to the [NiFe] H2‐binding active site. Replacement of this amino acid with alanine induces O2 sensitivity, and this has been attributed to the role of the histidine in enabling the reversible O2‐induced over‐oxidation of the [Fe4S3Cys2] proximal cluster possessed by all O2‐tolerant MBH. We have created an Escherichia coli Hyd‐1 His‐to‐Ala variant and report O2‐free electrochemical measurements at high potential that indicate the histidine‐mediated [Fe4S3Cys2] cluster‐opening/closing mechanism also underpins anaerobic reactivation. We validate these experiments by comparing them to the impact of an analogous His‐to‐Ala replacement in Escherichia coli Hyd‐2, a [NiFe]‐MBH that contains a [Fe4S4] center.
Seriation, the method out of a chemist's mind
Authors: Tóth Gergely , Amari‐Amir Sasan
Published: February 2018

Seriation is the practice of performing row and column permutations on data matrices to reveal clusters and hidden patterns within and between them. Seriation has been a known problem to tackle in the literature for over a century except chemical data where there are a fewer than a handful of researchers who have knowingly worked on this technique. The aim of this paper is to give seriation examples on chemical data and to propose the systematic use of seriation as a possible intuitive tool between data preprocessing and explanatory data analysis. Seriation itself performs the descriptive and exploratory data evaluations at a qualitative level with more limited efficiency than the specialized methods, but it may suggest to use clustering, variable selection, principal component analysis, and modeling. Different databases were used to check the versatility of seriation methods: benchmark ones on iris and wine, radioactivity data of sand mines, coin metal compositions, bioactivity of anticancer compounds, features of essential oils, and a reaction kinetic mechanism of biofuel combustion.
Ternary Mixed‐Valence Organotin Copper Selenide Clusters
Authors: Rinn Niklas , Guggolz Lukas , Lange Jurek , Chatterjee Sangam , Block Theresa , Pöttgen Rainer , Dehnen Stefanie
Published: February 2018

Reactions of the organotin selenide chloride clusters [(R1SnIV)3Se4Cl] (A, R1=CMe2CH2C(O)Me) or [(R1SnIV)4Se6] (B) with [Cu(PPh3)3−xClx] yield cluster compounds with different inorganic, mixed‐valence core structures: [Cu4SnIISnIV6Se12], [Cu2SnII2SnIV4Se8Cl2], [Cu2SnIISnIV4Se8], [Cu2SnII2SnIV2Se4Cl4], and [Cu2SnIV2Se4]. Five of the compounds, namely [(CuPPh3)2{(R1SnIV)2Se4}] (1), [(CuPPh3)2SnII{(R2SnIV)2Se4}2] (2), [(CuPPh3)2(SnIICl)2{(RSnIV)2Se4}2] (3) [(CuPPh3)2(SnIICu2){(R1SnIV)2Se4}3] (4), and [Cu(CuPPh3)(SnIICu2){(R1SnIV)2Se4}3] (5) are structurally closely related. They are based on [(CuPPh3)2{(RSnIV)2Se4}n] aggregates comprising [(RSnIV)2Se4] and [CuPPh3] building units, which are linked by further metal atoms. A sixth compound, [(CuPPh3)2(SnIICl)2{(R1SnIVCl)Se2}2] (6), differs from the others by containing [(RSnIVCl)Se2] units instead, which affects the absorption properties. The compounds were analyzed by single‐crystal X‐ray diffraction, NMR and 119Sn Mössbauer spectroscopy, DFT calculations as well as optical absorption experiments.
Ethers as Oxygen Donor and Carbon Source in Non‐hydrolytic Sol–Gel: One‐Pot, Atom‐Economic Synthesis of Mesoporous TiO2–Carbon Nanocomposites
Authors: Escamilla‐Pérez Angel Manuel , Louvain Nicolas , Boury Bruno , Brun Nicolas , Mutin P. Hubert
Published: February 2018

Mesoporous TiO2–carbon nanocomposites were synthesized using an original non‐hydrolytic sol–gel (NHSG) route, based on the reaction of simple ethers (diisopropyl ether or tetrahydrofuran) with titanium tetrachloride. In this atom‐economic, solvent‐free process, the ether acts not only as an oxygen donor but also as the sole carbon source. Increasing the reaction temperature to 180 °C leads to the decomposition of the alkyl chloride by‐product and to the formation of hydrocarbon polymers, which are converted to carbon by pyrolysis under argon. The carbon–TiO2 nanocomposites and their TiO2 counterparts (obtained by calcination) were characterized by nitrogen physisorption, XRD, solid state 13C NMR and Raman spectroscopies, SEM, and TEM. The nanocomposites are mesoporous with surface areas of up to 75 m2 g−1 and pore sizes around 10 nm. They are composed of aggregated anatase nanocrystals coated by an amorphous carbon film. Playing on the nature of the ether and on the reaction temperature allows control over the carbon content in the nanocomposites. The nature of the ether also influences the size of the TiO2 crystallites and the morphology of the nanocomposite. To further characterize the carbon coating, the behavior of the carbon‐TiO2 nanocomposites and bare TiO2 samples toward lithium insertion–deinsertion was investigated in half‐cells. This simple NHSG approach should provide a general method for the synthesis of a wide range of carbon–metal oxide nanocomposites.
Sensitive and Selective Detection of Phosgene, Diphosgene, and Triphosgene by a 3,4‐Diaminonaphthalimide in Solutions and the Gas Phase
Authors: Wang Shao‐Lin , Zhong Lin , Song Qin‐Hua
Published: February 2018

Phosgene and its substitutes, diphosgene and triphosgene, are highly toxic and widely used chemicals, so it is necessary to investigate their reactivity and develop facile, sensitive, and specific methods for detecting them. In this work, we have developed a new 1,8‐naphthalimide‐based fluorescent chemosensor, Phos‐2, which exhibits high sensitivity (detection limits: 0.2–0.7 nm), high selectivity to phosgene and its substitutes over nitric oxide (NO), various acyl chlorides, and nerve agent mimics in solutions. Based on investigation of the reaction kinetics of Phos‐2 with phosgene and its substitutes, a two‐step sensing mechanism was clarified. The second‐order rate constants (k2) of Phos‐2 reveal that the relative rate constants of phosgene, diphosgene, and triphosgene are 40:4:1. Moreover, a Phos‐2 test paper has been fabricated as a low‐cost, sensitive (≈5 ppm from observation by the naked eye or 0.1 ppm from a measurement), and efficient method for visual detection of a low concentration of phosgene in the gas phase.
Covalent Immobilization of (−)‐Riboflavin on Polymer Functionalized Silica Particles: Application in the Photocatalytic E→Z Isomerization of Polarized Alkenes
Authors: Metternich Jan B. , Sagebiel Sven , Lückener Anne , Lamping Sebastian , Ravoo Bart Jan , Gilmour Ryan
Published: February 2018

The covalent immobilization of the biomimetic, photo‐organocatalyst (−)‐riboflavin on silica micro‐ and nanoparticles via atom transfer radical polymerization (ATRP) is disclosed. Given the effectiveness of (−)‐riboflavin as a versatile, environmentally benign photocatalyst, an immobilization strategy based on acrylate‐linker modification of the catalyst core and controlled polymerization on initiator pre‐functionalized silica particles has been developed. Validation of this approach is demonstrated in the E→Z isomerization of a benchmark cinnamonitrile (Z/E up to 88:12) with 0.97 mol % catalyst loading. Characterization of the immobilized photocatalyst supports covalent embedding of the catalyst in the polymeric brushes on the silica particle surface.
The Interaction Modes of Haloimidazolium Salts in Solution
Authors: Schulz Nils , Sokkar Pandian , Engelage Elric , Schindler Severin , Erdelyi Mate , Sanchez‐Garcia Elsa , Huber Stefan M.
Published: February 2018

Invited for the cover of this issue is the group of Elsa Sanchez‐Garcia at the Universität Duisburg‐Essen and Stefan M. Huber at the Ruhr‐University Bochum. The image depicts the crystal structure of an iodoimidazolium salt showing one of the possible interactions. Read the full text of the article at 10.1002/chem.201705032.
Supramolecular Recognition of Three Way Junction DNA by a Cationic Calix[3]carbazole
Authors: Yang Zhaozheng , Chen Yan , Li Gang , Tian Zhangmin , Zhao Liang , Wu Xi , Ma Qi , Liu Mingzhe , Yang Peng
Published: February 2018

Invited for the cover of this issue is the group of Peng Yang at the Shenyang Pharmaceutical University. The image depicts how the calix[3]carbazole interacts with three way junctions DNA. Read the full text of the article at 10.1002/chem.201705564.
Arene‐Ligand‐Free Ruthenium(II/III) Manifold for meta‐C−H Alkylation: Remote Purine Diversification
Authors: Fumagalli Fernando , Warratz Svenja , Zhang Shou‐Kun , Rogge Torben , Zhu Cuiju , Stückl A. Claudia , Ackermann Lutz
Published: February 2018

meta‐Selective C−H alkylations of bioactive purine derivatives were accomplished by versatile ruthenium catalysis. Thus, the arene‐ligand‐free complex [Ru(OAc)2(PPh3)2] enabled remote C−H functionalizations with ample scope and excellent levels of chemo‐ and positional selectivities. Detailed experimental and computational mechanistic studies provided strong support for a facile C−H activation within a ruthenium(II/III) manifold.
Mutual inversion of flurbiprofen enantiomers in various rat and mouse strains
Authors: de Bruin Natasja , Ferreirós Nerea , Schmidt Mike , Hofmann Martine , Angioni Carlo , Geisslinger Gerd , Parnham Michael John
Published: February 2018

Flurbiprofen (F) is a nonsteroidal anti‐inflammatory drug (NSAID) used therapeutically as the racemate of (R)‐enantiomer and (S)‐enantiomer. The inversion of RF to SF and vice versa was investigated in C57Bl/6 and SJL mice and Dark Agouti and Lewis rats. The enzyme α‐methylacyl‐CoA racemase (AMACR) is involved in the chiral inversion pathway that converts members of the 2‐arylpropionic acid NSAIDs from the R‐enantiomer to the S‐enantiomer. We studied C57Bl/6 mice deficient in AMACR postulating that they should show reduced inversion of RF to SF. In line with the data of others in mice, (R)‐inversion to (S)‐inversion was relatively high in both the C57Bl/6 and SJL mice (fraction inverted, FI = 37.7% and 24.7%, respectively). In contrast, in AMACR deficient mice, there was no measurable peak for SF after administration of RF. The results in both rat strains (Dark Agouti and Lewis rats, FI = 1.4% and 4.1%, respectively) confirm the low chiral inversion of the enantiomers of flurbiprofen in the rat, as observed by other authors in the Sprague‐Dawley strain (<5%). From the present results, we conclude that for the study of flurbiprofen enantiomers, the rat is more suitable than the mouse as a model for the human in which (R)‐inversion to (S)‐inversion is negligible.
Wie unordentlich sind Proteine?
Authors: Groß Michael
Published: February 2018

Mehr als 100.000 Proteinstrukturen sind zwischen in atomarer Auflösung bekannt, alle Aminosäuren schön ordentlich aufgereiht und zu einer dreidimensionalen Raumstruktur gefaltet, deren Architektur die biologische Funktion ermöglicht. Doch seit 20 Jahren mehren sich die Beispiele dafür, dass auch ungeordnete Proteine in der Zelle nicht nur vorkommen, sondern sogar wichtige Aufgaben erfüllen können.
A STUDY ON SPECTRAL MOMENTS OF GRAVITY FIELD WITH APPLICATION TO CRUSTAL STRUCTURE IMAGING OF TARIM BASIN
Authors: Wen‐Cai YANG , Yan‐Yun SUN , Zun‐Ze HOU , Chang‐Qing YU
Published: February 2018

Modern geophysical techniques provide great amount data of geophysical field that contain rich information about crustal structures, which can be extracted for geo‐mapping based on theory of mathematical physics. This paper shows that the high‐order spectral moments of regional gravity data include information of geometrical contour surface, which can be used for selection, positioning and classification of some types of geological structures. By using second‐order spectral moments of Bouguer gravity data, one can calculate their statistical unvaried quantities and the ridge‐like parameter, which characterizes the crustal deformation belts and can be used for mapping regional distribution of the deformation belts. The boundaries between areas of strong or weak ridge‐like parameters represent boundaries of different structural units. We can further compute the second‐order spectral moments of the statistical unvaried quantities to calculate the boundary parameter, which may be used for tracing and positioning the structural boundaries after some enhancement are added. This paper gives all the formula for computing the ridge and the boundary parameters, and testing results on crustal structural analysis in Tarim basin, Northwest China. As the results, deep High‐ and Low‐density belts within the Tarim basin are located precisely, providing important basic images for oil/gas exploration in the basin.
THE ADVANCEMENT OF LUNAR GRAVITY MODEL DUE TO THE DEVELOPMENT OF SPACE TRACKING TECHNIQUES
Authors: Fei LI , Wei‐Feng HAO , Jian‐Guo YAN , Xian‐Yuan SHAO , Mao YE , Chi XIAO
Published: February 2018

Based on the three modes of lunar spacecraft tracking techniques: Earth‐based tracking mode, high‐low satellite‐to‐satellite tracking mode and low‐low satellite‐to‐satellite tracking mode, the development of lunar gravity models could be divided into 4 stages. First, we introduce the principle, technical characteristics of the different tracking modes, and the representative gravity models, and then make comments on these models’ precision. Further, through the comparison of gravity anomaly precision, characteristics and orbit determination precision from different stages’ lunar gravity field models, we conclude that: the advancement of space tracking techniques has significantly improved the precision of lunar gravity model and effectively promotes the understanding of lunar interior structure and the reliability of lunar satellite orbit determination. Finally, we analyze the deficiency of current lunar gravity models and give a perspective of future space tracking techniques.
Temperature‐responsive Catalyst for the Coupling Reaction of Carbon Dioxide and Propylene Oxide
Authors: Zhuo Chunwei , Qin Yusheng , Wang Xianhong , Wang Fosong
Published: February 2018

The selective synthesis of polypropylene carbonate (PPC) and cyclic propylene carbonate (CPC) from coupling reaction of CO2 and propylene oxide (PO) is a long term pursuing target. Here we report that a temperature controllable porphyrin aluminum catalyst using 5,10,15,20‐tetra(1,2,3,4,5,6, 7,8‐octahydro‐1,4:5,8‐dimethanoanthracen‐9‐yl)porphyrin as ligand, once in conjunction with suitable onium salt, achieved single cycloaddition or copolymerization reaction. Only cycloaddition reaction happened at temperature above 75 °C to produce 100% CPC, whereas copolymerization became dominant to afford PPC with selectivity over 99% at 25 °C, and the obtained PPC showed over 99% carbonate linkage and 92% head‐to‐tail structure. Based on systematic analysis of the electronic and steric feature in the porphyrin ligand, it was found that the electronic feature of the substituent in porphyrin ligand was decisive for PPC selectivity, porphyrin ligand bearing strong electron‐donating substituents displayed a significantly reduced tolerance towards increased temperature with respect to PPC formation. Therefore, temperature‐responsive catalyst could be designed by suitable modification in porphyrin ligand, and such accurate synthesis of target product by one catalyst may create a useful and facile platform for selective PPC or CPC production.
Reassessing the value of high‐volume cancer care in the era of precision medicine
Authors: Cole Alexander P. , Sun Maxine , Lipsitz Stuart R. , Sood Akshay , Kibel Adam S. , Trinh Quoc‐Dien
Published: February 2018

The ethical and economic discussions regarding the extreme costs of many new cancer therapies are familiar. The authors have long held that changes in cancer care delivery also are an important strategy, yielding large benefits at potentially far lower costs. To put this into context, the authors performed an analysis to compare the overall survival of patients receiving a complex oncologic surgery, radical cystectomy, at high‐volume and low‐volume centers. Propensity score weighting was performed to simulate random allocation into high‐volume versus low‐volume centers, as would be the case in a prospective trial. On average, patients undergoing surgery at high‐volume centers survived 15 months longer than those treated at low‐volume centers (57.0 months vs 41.8 months). Although there certainly are caveats in contrasting the survival benefit of different care settings with anticancer agents, this differential clearly rivals or exceeds the benefit of many expensive, recently approved agents. As the debate regarding the costs of cancer therapies continues, it is worth remembering that investments in simple systems‐based changes to improve cancer care delivery remain an important and likely cost‐effective strategy with which to improve the survival of patients with cancer. Cancer 2018;124:1319‐21. © 2018 American Cancer Society.
Comparative analysis of the transcriptome of injured nerve segments reveals spatiotemporal responses to neural damage in mice
Authors: Shin Jung Eun , Ha Hongseok , Cho Eun Hye , Kim Yoon Ki , Cho Yongcheol
Published: February 2018

Nerves are particularly vulnerable to damage due to their unique structure with meter‐long axons. In the peripheral nervous system neurons and Schwann cells can activate the injury‐response program that directs axons to either regenerate or degenerate after traumatic nerve injury. However, the differences between the genetic programs driving nerve regeneration and degeneration have not yet been described extensively. To understand these differences, in this study we have compared the injury‐induced transcriptomic changes between the regenerating proximal segment and the degenerating distal segment of a transected nerve, at different post‐injury time points. We analyzed the spatiotemporal dynamics of the mouse transcriptome using a sciatic nerve‐injury model by means of RNA sequencing. The results of the differentially regulated genes (DEGs) analysis show that some DEG groups are similarly regulated in both proximal and distal segments, and primarily display a positive correlation. However, some DEG groups are exclusively regulated in either the proximal or the distal segment, suggesting that these DEG groups constitute a genetic network for distinguishing the regenerative and degenerative responses. In addition, our gene ontology analysis revealed an enrichment of particular biological processes in different phases and locations. Thus, our data provide a spatiotemporal profile of the transcriptomes that are differentially regulated in either regenerating or degenerating nerves, in vivo. The specific biological processes enriched in the DEG groups might delineate the injury‐responsive program that induces contrasting regenerative and degenerative responses in different nerve segments.