bluuebunny/crossref_metadata_2025_split huggingface dataset:
Potassium‐rich sandstones within the Gale impact crater, Mars: The APXS perspective
Authors: Thompson L. M. , Schmidt M. E. , Spray J. G. , Berger J. A. , Fairén A. G. , Campbell J. L. , Perrett G. M. , Boyd N. , Gellert R. , Pradler I. , VanBommel S. J. 
Published: September 2016

AbstractThe Alpha Particle X‐ray spectrometer (APXS) on board the Curiosity rover at the Kimberley location within Gale crater, Mars, analyzed basaltic sandstones that are characterized by potassium enrichments of 2 to 8 times estimates for average Martian crust. They are the most potassic rocks sampled on Mars to date. They exhibit elevated Fe, Mg, Mn and Zn and depleted Na, Al, and Si. These compositional characteristics are common to other potassic sedimentary rocks analyzed by APXS at Gale but distinct from other landing sites and Martian meteorites. CheMin and APXS analysis of a drilled sample indicate mineralogy dominated by sanidine, Ca‐rich and Ca‐poor clinopyroxene, magnetite, olivine, and andesine. The anhydrous mineralogy of the Kimberley sample, and the normative mineralogy derived from APXS of other Bathurst class rocks, together indicate provenance from one or more potassium‐rich magmatic or impact‐generated source rocks on the rim of Gale crater or beyond. Elevated Zn, Ge, and Cu suggest that a localized area of the source region(s) experienced hydrothermal alteration, which was subsequently eroded, dispersed, and diluted throughout the unaltered sediment during transport and deposition. The identification of the basaltic, high potassium Bathurst class and other distinct rock compositional classes by the APXS, attests to the diverse chemistry of crustal rocks within and in the vicinity of Gale crater. We conclude that weathering, transport, and diagenesis of the sediment did not occur in a warm and wet environment, but instead under relatively cold and wet conditions, perhaps more fitting with processes typical of glacial/periglacial environments.
On the possibility of viscoelastic deformation of the large south polar craters and true polar wander on the asteroid Vesta
Authors: Karimi Saman , Dombard Andrew J. 
Published: September 2016

AbstractThe asteroid Vesta, located within the inner asteroid belt, is a differentiated body with a prominent rotational bulge. NASA's Dawn mission revealed the presence of two large, relatively shallow impact craters in the south polar region, one with a high‐standing central peak. The shallowness and prominent central peak are reminiscent of large craters on some icy satellites that may have experienced strong topographic relaxation. The location of these basins near the south pole is also unusual and suggests true polar wander, which requires relaxation of the rotational bulge. Thus, we use the finite element method and a viscoelastic rheology to examine the feasibility of relaxation processes operating on Vesta. Given the plausible thermal state of Vesta by the decay of long‐lived radioactive elements, we find that the lithosphere is not compliant enough to allow strong relaxation of the large south polar craters, and thus the peculiar morphology is possibly a product of the formation of these large basins at a planetary scale. Additionally, the asteroid has not been warm enough to permit the relaxation of the rotational bulge. Consequently, these craters both happened to form near the south pole, as unlikely as that is.
Catalytic Cycloisomerization–Fluorination Sequence of N‐Propargyl Amides by Iodoarene/HF⋅Pyridine/Selectfluor Systems
Authors: Asari Naoki , Takemoto Yusuke , Shinomoto Yukino , Yagyu Takuma , Yoshimura Akira , Zhdankin Viktor V. , Saito Akio 
Published: September 2016

AbstractAs a first example of metal‐free and catalytic fluorinative transformations of alkynes, we developed a cycloisomerization–fluorination sequence of N‐propargyl amides catalyzed by an iodine(III) species. The iodine(III) catalyst is in situ generated from iodoarene as a precatalyst with Selectfluor as a fluorinating oxidant in the presence of HF⋅pyridine.
Delayed massive epistaxis from traumatic intracranial aneurysm after blunt facial injury
Authors: Nakamura Hajime , Fujinaka Toshiyuki , Tasaki Osamu , Yoshimine Toshiki 
Published: September 2016

CasesTraumatic intracranial aneurysm following blunt head injury is uncommon but can be induced by extension of skull base fracture and causes unexpected hemorrhagic complications. We present two cases of traumatic intracranial aneurysm in the paraclinoid area that was revealed by delayed massive epistaxis. Lack of initial neurological deficits omitted screening for cerebrovascular injury.OutcomeInternal trapping was carried out using endovascular techniques in both cases, with extracranial–intracranial bypass in one case. No recurrent bleeding occurred in either case.ConclusionTo prevent unexpected delayed life‐threatening hemorrhagic accidents, careful assessment of skull‐base fracture is prerequisite, even in cases of mild facial injury.
Tandem Ring‐Opening–Ring‐Closing Metathesis for Functional Metathesis Catalysts
Authors: Nagarkar Amit A. , Yasir Mohammad , Crochet Aurelien , Fromm Katharina M. , Kilbinger Andreas F. M. 
Published: September 2016

AbstractUse of a tandem ring‐opening–ring‐closing metathesis (RORCM) strategy for the synthesis of functional metathesis catalysts is reported. Ring opening of 7‐substituted norbornenes and subsequent ring‐closing metathesis forming a thermodynamically stable 6‐membered ring lead to a very efficient synthesis of new catalysts from commercially available Grubbs’ catalysts. Hydroxy functionalized Grubbs’ first‐ as well as third‐generation catalysts have been synthesized. Mechanistic studies have been performed to elucidate the order of attack of the olefinic bonds. This strategy was also used to synthesize the ruthenium methylidene complex.
Hochgenaue Berechnung der Kohäsionsenergie von festem Argon mit Abweichungen im J/mol‐Bereich
Authors: Schwerdtfeger Peter , Tonner Ralf , Moyano Gloria E. , Pahl Elke 
Published: September 2016

AbstractWir präsentieren Rechnungen der Kohäsionsenergie von Argon in der kubisch und hexagonal dichtesten Kugelpackung mit einer noch nie zuvor erreichten Genauigkeit im Bereich von 5 J mol−1 (dies entspricht 0.05 % der gesamten Kohäsionsenergie). Dieselbe relative Genauigkeit im Vergleich zu experimentellen Daten wurde auch für die Gitterkonstante des flächenzentrierten Gitters mit einer absoluten Abweichung von ungefähr 0.003 Å erreicht. Die hohe Genauigkeit wurde durch die Verwendung von wellenfunktionsbasierten Methoden im Rahmen einer Mehrkörperentwicklung der Wechselwirkungsenergie ermöglicht. Statische Beiträge der Zwei‐, Drei‐ und Vierkörperfragmente des Kristalls, die jeweils mit einer Genauigkeit von unter 1 J mol−1 berechnet wurden, wurden durch harmonische und anharmonische Nullpunktschwingungskorrekturen ergänzt. Für Edelgas‐Festkörper erreicht die Computerchemie hiermit experimentelle Genauigkeit oder übertrifft diese sogar.
Stereo‐ and Regioselective Alkyne Hydrometallation with Gold(III) Hydrides
Authors: Pintus Anna , Rocchigiani Luca , Fernandez‐Cestau Julio , Budzelaar Peter H. M. , Bochmann Manfred 
Published: September 2016

AbstractThe hydroauration of internal and terminal alkynes by gold(III) hydride complexes [(C^N^C)AuH] was found to be mediated by radicals and proceeds by an unexpected binuclear outer‐sphere mechanism to cleanly form trans‐insertion products. Radical precursors such as azobisisobutyronitrile lead to a drastic rate enhancement. DFT calculations support the proposed radical mechanism, with very low activation barriers, and rule out mononuclear mechanistic alternatives. These alkyne hydroaurations are highly regio‐ and stereospecific for the formation of Z‐vinyl isomers, with Z/E ratios of >99:1 in most cases.
Mechanistic Insight into the Nitric Oxide Dioxygenation Reaction of Nonheme Iron(III)–Superoxo and Manganese(IV)–Peroxo Complexes
Authors: Hong Seungwoo , Kumar Pankaj , Cho Kyung‐Bin , Lee Yong‐Min , Karlin Kenneth D. , Nam Wonwoo 
Published: September 2016

AbstractReactions of nonheme FeIII–superoxo and MnIV–peroxo complexes bearing a common tetraamido macrocyclic ligand (TAML), namely [(TAML)FeIII(O2)]2− and [(TAML)MnIV(O2)]2−, with nitric oxide (NO) afford the FeIII–NO3 complex [(TAML)FeIII(NO3)]2− and the MnV–oxo complex [(TAML)MnV(O)]− plus NO2−, respectively. Mechanistic studies, including density functional theory (DFT) calculations, reveal that MIII–peroxynitrite (M=Fe and Mn) species, generated in the reactions of [(TAML)FeIII(O2)]2− and [(TAML)MnIV(O2)]2− with NO, are converted into MIV(O) and .NO2 species through O−O bond homolysis of the peroxynitrite ligand. Then, a rebound of FeIV(O) with .NO2 affords [(TAML)FeIII(NO3)]2−, whereas electron transfer from MnIV(O) to .NO2 yields [(TAML)MnV(O)]− plus NO2−.
Rotationally Active Ligands: Dialing‐Up the Co‐conformations of a [2]Rotaxane for Metal Ion Binding
Authors: Baggi Giorgio , Loeb Stephen J. 
Published: September 2016

AbstractA novel [2]rotaxane was constructed that has a bidentate N,N′‐chelate as part of a rigid, H‐shaped axle and a 24‐membered crown ether macrocycle containing six ether O‐atoms and an olefinic group as the wheel. This unique topology produces a ligand with the ability to dial‐up different donor sets for complexation to metal ions by simply rotating the wheel about the axle. The solution and solid‐state structures of the free ligand and complexes with Li+ and Cu+ show how the ligand adopts different rotational co‐conformations for each. The Li+ ion uses the N,N′‐chelate and O‐donors while the Cu+ center is coordinated to both O‐donors and the olefinic group. This concept of rotationally active ligands should be possible with a wide variety of donor sets and could find broad application in areas of coordination chemistry, such as catalysis and metal sequestration.
Synthesis, structures, and density functional theory computational study of thiophene‐containing and fluorodecorated imine‐linked polymers
Authors: Altarawneh Suha S. , Jazzazi Taghreed M. A. , Ababneh Taher S. , Al Shboul Tareq M. A. , Al Jaafreh Ibtesam Y. 
Published: September 2016

ABSTRACTA new series of extended–conjugated and thermally stable thiophene‐containing imine‐linked polymers were synthesized via a Schiff‐base condensation reaction between aryl aldehydes and 2,6‐diaminopyridine building blocks. The backbones of the polymers were functionalized with phenyl, fluorosubstituted phenyl, thienyl, and pyridyl aromatic rings. The successful synthesis was confirmed with spectrochemical characterization techniques, including IR, 1H‐NMR, 13C‐NMR, and elemental analyses. The electronic properties of the polymers were investigated with ultraviolet–visible (UV–vis) absorption spectroscopy; the properties were collected experimentally and calculated with density functional theory (DFT) in the gas phase. The maximum absorption calculated from DFT was higher than the experimental values by about 60 nm; this was attributed to the absence of the solvent effect in the DFT case. The frontier molecular orbital ((HOMO) highest occupied molecular orbital and (LUMO) lowest unoccupied molecular orbital), optical band gap (Eg), and total energy (ET) values of the optimized structures were calculated. Apparently, there was a significant relation between the number of thiophene rings and the resulting Eg and ET values. As the number of thiophene rings in the polymer chain increased, Eg and ET decreased, and the thermal stability of the polymers increased. Eg and the absorption band edges were determined experimentally from the UV–vis and transmittance spectra, respectively. Poly(terthienyl–azomethine–pyridine–azomethine), with the highest thiophene content, had the lowest experimental and calculated Eg values (2.10 and 2.63 eV, respectively). In contrast, upon fluorination, poly[(2,5‐dithienyl–1,4‐difluorobenzene)–azomethine–pyridine–azomethine] exhibited the highest Eg (2.81 eV) and absorption band edges (2.94 eV), whereas the thermal stability decreased to 250 °C. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44331.
Production and characterization of films containing poly(hydroxybutyrate) (PHB) blended with esterified alginate (ALG‐e) and poly(ethylene glycol) (PEG)
Authors: Ribeiro Lopes Jamilly , Azevedo dos Reis Rodrigo , Almeida Luís Eduardo 
Published: September 2016

ABSTRACTAlternative materials have long been studied and developed to replace conventional skin dressings with the emergence of new biopolymers and development of polymeric film fabrication techniques. As a new material for polymeric dressings, films of poly(hydroxybutyrate) (PHB) blended with esterified alginate (ALG‐e) and poly(ethyleneglycol) was studied. The esterification of sodium alginate (ALG‐e) generated a material with some amphiphilic characteristics and increased compatibility with the PHB. PEG was added as plasticizer in PHB/ALG‐e films was also tested, since PEG is often used in blends with PHB to improve flexibility and reduce hydrophobicity. At the amounts studied, it was found that both PEG and ALG‐e increase the degree of crystallinity, but a decrease was observed in the hydrophobic nature of PHB films. At the maximum concentration of ALG‐e and PEG used an increase in water vapor permeability and a decrease in tensile strength was reached due to the synergistic effect caused by better homogenization of PEG and ALG‐e in the PHB matrix. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44362.
Imperilled species in aquatic ecosystems: emerging threats, management and future prognoses
Authors: Gangloff Michael M. , Edgar Graham J. , Wilson Ben 
Published: September 2016

Abstract

Earth's aquatic habitats are some of its most important ecosystems and support populations of many of its most imperilled species. The future demands of Earth's growing human populations will increasingly stress its aquatic resources on multiple spatial and temporal scales, as highlighted by numerous authors when predicting trends in biodiversity in many key aquatic hotspots.
Identifying key stressors and understanding potential linkages between these stressors are important first steps to mitigating human impacts on at‐risk aquatic resources. Here, an overview is provided of the established and emerging threats to aquatic biodiversity at local, regional and global scales, including emerging diseases, expanding influence of invasive species, new industries, and the accelerating trajectory of climate change, as well as perspectives on potential management strategies.
Copyright © 2016 John Wiley & Sons, Ltd.
Connecting the shifting currents of aquatic science and policy
Authors: Ormerod S. J. , Ray G. Carleton 
Published: September 2016

Abstract

The interface between science and policy is often contentious and characterized by mutual suspicion, yet is critical to both halves of the divide. The application of science to real‐world problems is ultimately one of the greatest markers of scientific achievement, while policy‐makers can reduce the risks of failure by drawing on good evidence. The disproportionately large resource value of inland waters and marine systems together make synergies between science and policy particularly pertinent.
Aquatic science has shaped major policy or regulatory legislation, with examples such as the US Clean Water Act (1972) and EU Water Framework Directive (2000/60/EC) deeply rooted in evidence. Modern policy examples are also emerging that can respond to the need for resilience to global change, the protection of natural capital and the sustainable management of ecosystem services. However, practical applications so far remain rudimentary.
There have been extensive uses of aquatic conservation science to evaluate the outcomes from past policy implementation. Examples are the role of the EU Large Combustion Plants Directive (88/609/EEC), EU Urban Wastewater Treatment Directive (91/271/EEC) and the US Clean Water Act (1972) in restoring polluted, acidified, and urbanized fresh waters. However, larger‐scale and longer‐term data are required to reveal such policy effects more fully. Evaluations of policies to address recent problems in marine waters affected by climate change, acidification, or anoxia are far less complete.
The authors suggest that aquatic scientists can play a pivotal role in identifying gaps or failings in policy or regulatory practice, and we urge our colleagues in aquatic conservation to recognize this role with conviction. A specific policy need is identified – to recognize more fully the importance of connectivity among land, inland waters, and seas to avoid high environmental costs, to capture conservation benefits, and to build resilience in aquatic ecosystems as, arguably, the world's most important environments.
Copyright © 2016 John Wiley & Sons, Ltd.
Revisiting the Vomeronasal System From an Integrated Perspective
Authors: Salazar Ignacio , Barrios Arthur W. , SáNchez‐Quinteiro Pablo 
Published: September 2016

ABSTRACT“Olfactory subsystems” is a relatively new terminology to refer to the different regions of the nasal cavity featuring olfactory sensory neurons. In mice, the olfactory chemical cues are detected in four well delimited areas: the main olfactory epithelium, the septal organ, Grüneberg's ganglion, and the sensory epithelium of the vomeronasal organ. Nevertheless, such distribution is by no means exhibited by all mammals. In microsmatic mammals –humans included– the only existing olfactory subsystem is the main olfactory epithelium. This raises the question of whether the lack of certain olfactory structures in those species implies that they are unable to identify certain olfactory signals, or on the contrary, their main olfactory epithelium assumes such role. It would be interesting to determine, in the context of biomedical research, if the sense of smell in humans is fully or partially endowed with the wide range of functions assigned to the vomeronasal system in mice. If it is not, presumptive implications of the lack of such functions should be addressed in human health and well‐being. Anat Rec, 299:1488–1491, 2016. © 2016 Wiley Periodicals, Inc.
Landing Auto‐Pilots for Aircraft Motion in Longitudinal Plane using Adaptive Control Laws Based on Neural Networks and Dynamic Inversion
Authors: Lungu Mihai , Lungu Romulus 
Published: September 2016

AbstractThis paper presents two new automatic landing systems (ALSs) for aircraft motion in longitudinal plane; the model of the landing geometry determines the flight trajectory and the aircraft calculated altitude; the flight trajectory during landing consists of two parts: the glide slope and the flare. Both designed ALSs have an adaptive system (ACS) for the aircraft output's control; for the first ALS, the output vector consists of the flying altitude and the longitudinal velocity, while, for the second ALS, the output variables are the pitch angle and the longitudinal velocity of aircraft. The second variant of ALS also contains an altitude controller providing the calculated pitch angle. The calculated altitude (for the first ALS), the calculated pitch angle (for the second ALS), and the desired flight velocity are provided to the ACS by means of a block consisting of two reference models. ACS is based on the dynamic inversion concept and contains an adaptive controller which includes a linear dynamic compensator, a state observer, a neural network, and a Pseudo Control Hedging block. The paper is focused both on the design of the two ALSs and on their complex software implementation and validation.
Verbundverhalten von Vollgewindeschrauben in Brettschichtholzbauteilen
Authors: Ayoubi Mazen 
Published: September 2016

AbstractZur Beschreibung des Verbundverhaltens und der Kraftübertragung von selbstbohrenden Vollgewindeschrauben bei großen Verbund‐ und Einbindelängen in Brettschichtholzbauteilen wurden experimentelle, analytische und numerische Untersuchungen am Lehrstuhl für Tragkonstruktionen der RWTH Aachen in Zusammenarbeit mit dem Institut für Bauforschung (ibac) der RWTH Aachen durchgeführt. Die experimentellen Untersuchungen umfassen mehr als 160 Pull‐Out‐Versuche sowie 84 Lasteinleitungsversuche, darüber hinaus Versuche zum Einfluss eines Längsrisses sowie einer eingebetteten Schraubenspitze auf das Verbundtragverhalten. Die parallel durchgeführten numerischen und analytischen Untersuchungen bilden die Basis zur Erstellung von Modellen zur Beschreibung des Tragverhaltens und der Kraftübertragung zwischen Schraube und Holz. Die gewonnenen Erkenntnisse ermöglichen die Bestimmung eines Bemessungsansatzes unter besonderer Berücksichtigung der Anisotropie des Holzes. In diesem Beitrag werden die Untersuchungsergebnisse, die im Rahmen des von der Deutschen Forschungsgemeinschaft (DFG) geförderten Projekts [1] ermittelt wurden, dargestellt. Teil 1 behandelt die experimentellen Untersuchungen [2], Teil 2 die analytischen und numerischen Betrachtungen sowie die Herleitung eines Verbundmodells zur Berechnung der Verankerungslänge.
Genauigkeit. Zur Ausbildung einer epistemischen Tugend im ,langen 19. Jahrhundert‘
Authors: Krajewski Markus 
Published: September 2016

AbstractExactitude. The Genesis of an Epistemic Virtue in the ‘Long Nineteenth Century’. The article examines the genesis of exactitude as an epistemic virtue in both scholarly and scientific contexts in the 19th century, mainly in Prussia. Starting with an influential historiographic work on ancient metrology three semantic fields of accuracy, exactitude and precision are differentiated and pursued in their etymologies as well as applications. The historic situation between 1790 and 1860 is identified as the crucial period when the exactness of the exact sciences as well as the notion of accuracy in the humanities start to diverge from one another in order to develop an epistemic virtue each on its own.
Die Neuordnung pflanzengeografischen Wissens als „Transitzone“ Wallacea. Ein amerikanisches Expansionsprojekt auf den Philippinen, 1902–1928
Authors: Walch Sonja 
Published: September 2016

AbstractThe Reshaping of Phytogeographical Knowledge as the “Transition zone” Wallacea: An American Expansion Project in the Philippines, 1902–1928. This paper examines the development of a concept that to this day plays an important role in biogeography: the region Wallacea. Focussing on the work of the American tropical botanist Elmer D. Merrill in the Philippines, I argue that his research on the geographical movement and settlement of Philippine plants reflects a shift in the United States’ scientific and cultural understanding of the Pacific area towards a notion of “American tropics”. While inventorying plants for the American administration from 1901 to 1923, the composition of Philippine flora prompted Merrill to question biogeographical regionalization in Wallace's Malay Archipelago. Not being able to situate the Philippine flora within “Asian” or “Australasian” biota, Merrill described the islands as an area of trans‐regional plant migration. Together with the paleontologist Roy E. Dickerson, he later conceptualized the region Wallacea as biogeographical “transition zone” between the Philippines and Australia. In addition to the scientific conceptualization, Wallacea constitutes a space between two biogeographical subregions, whose flora was considered as being part of both, but could not be unambiguously attributed to either of these regions. In this respect, the plants resembled the inhabitants of the United States’ insular overseas territories, who were legally defined neither as aliens nor as citizens. In this sense, Wallacea embodies epistemic as well as geopolitical boundaries, while its case also illustrates some of the ways in which colonial interests in the usability of plants found expression in botanical research during the early period of American overseas expansion.