bluuebunny/crossref_metadata_2025 huggingface dataset:
Free Unsolvated Formaldehyde in Solutions: Influence of Temperature, Solvent Permittiity, and Total Formaldehyde Concentration
Authors: Silaev Michael M.
Published: September 2015

A mechanism of the initiated nonbranched-chain process of forming 1,2-alkanediols and carbonyl compounds in alcohol-formaldehyde systems is suggested. The quasi-steady-state treatment is used to obtain kinetic equations that can describe the nonmonotonic (with a maximum) dependences of the formation rates of the products on the concentration of free unsolvated formaldehyde. The experimental concentration of the free unsolvated form of formaldehyde are given at the different temperatures, solvent permittivity and total concentrations of formaldehyde in water and alcohols. An empirical equation for calculating the free formaldehyde concentration in alcohol-formaldehyde (including water/ethanediol-formaldehyde) systems at various temperatures and total formaldehyde concentrations and an equation for evaluating solvent concentrations in these systems were derived.
Une arme à double tranchant : le déploiement du portrait de la reine dans les édifices gouvernementaux et dans les caricatures québécoises
Authors: Desforges Josée
Published: September 2015

Since the recent increase in the number of representations of Queen Elizabeth II in Canadian government buildings, Quebec cartoonists have seized the motif of the royal portrait to denounce the Harper government’s uses of the sovereign’s image. Drawing on Louis Marin’s definition of representation, this article considers the powers granted by the state to the Queen’s portrait and highlights its critique in Quebec caricatures. Indeed, while the portrait of the Queen allows the Prime Minister to legitimize his authority, its satirical representations denounce the government’s re-actualization of an absent monarchy. The royal portrait is then satirized both as a powerless object and as a weapon threatening to overshadow other Canadian political and religious symbols.
Repeat Offenders: Reprinting Visual Satire Across France’s Long Eighteenth Century
Authors: Desplanque Kathryn
Published: September 2015

Dans cet article, nous nous penchons sur deux caricatures françaises du XVIIIe siècle et sur leurs différents tirages parus au courant des XVIIIe et XIXe siècles : Triomphe des Arts Modernes ou Carnaval de Jupiter, d’auteur inconnu, et L’Assemblée de Brocanteurs, attribuée au comte de Caylus. Empruntant aux méthodologies des études de la culture matérielle et visuelle, nous examinons la signification cachée du geste éditorial qui consiste à produire de nouveaux tirages de ces plaques de cuivre, geste riche de similarités avec la nature même de la satire et avec la matérialité de l’estampe. En déchiffrant l’iconographie dense de chaque image et en examinant les différences dans le fonctionnement de chaque estampe selon la date du tirage, nous traitons de la tendance de ces caricatures à citer de façon parasitique les cibles de leurs attaques. Par ailleurs, nous mobilisons l’interprétation de Miriam Hansen de l’essai de Walter Benjamin, « L’Oeuvre d’art à l’époque de sa reproductibilité technique », afin d’analyser l’importance de la matérialité de l’estampe par rapport au statut de chaque nouveau tirage et de réfléchir aux notions d’« image » vs « chose », et d’éloignement vs proximité.
The Theophilus Relief at Souillac and the Eleventh-Century Reforms of the Church
Authors: Krindle C. Ruth
Published: September 2015

Le relief de Théophile situé sur le mur occidental de la nef de l’église de Souillac (vers 1120–1140) est plus qu’une simple illustration de la légende théophilienne : il communique un message aux moines instruits. Puisant parmi certains thèmes moins connus de la légende, ce relief met en garde contre les desseins diaboliques sous-jacents à la nomination des dignitaires haut placés de l’Église. Soutenue par une analyse d’ensembles sculptés provenant des environs de Souillac, notre interprétation replace le relief de Théophile dans le contexte historique de la période de la réforme de l’Église qui venait de s’achever – réforme qui toucha principalement des questions relatives à la nomination du haut clergé alors que la vente par les simonistes de dignités ecclésiastiques fut éradiquée et la papauté prit en charge la sélection des métropolitains et évêques.
Bridging a gap in iron-sulfur cluster assembly
Authors: McCarthy Erin L. , Booker Squire J.
Published: September 2015

The cellular machinery that incorporates iron-sulfur clusters into proteins is directed to particular targets by adaptor proteins.
A Study of Chinese Reverse Mergers in United States Capital Markets
Authors: DuVal Charles W. , Quilliam Will
Published: September 2015

This article examines Chinese reverse mergers (RMs), historically a popular method for Chinese companies to enter the United States capital markets. The authors develop a regression model to identify the characteristics associated with successful Chinese RM companies and compare their long term performance to other benchmarks, to include U.S. reverse mergers, Chinese cross-listed firms and the Russell 2000.
The Construction of Organizational Structure : Connections with Autopoietic Systems Theory
Authors: Dissanayake Kumudinei , Takahashi Masayasu
Published: September 2015

This study aimed to conceptualize the formation of organizational structures from the constructionist perspective. Avoiding the extremisms in equilibrium- and processbased

theories, it adopts a recursivity-based approach, and draws most of its theoretical foundation from autopoietic systems theory. This study finds that organizations possess a "system organization,” formed through the shared sense of their actors and a “structural configuration,” which is founded on this shared sense. Based on the shared sense, this structural configuration is shaped by both formal organizational architecture and the temporal and contextual interactive processes of organizational actors. It suggests that organizational structures are unique constructions, subject to temporal and contextual variation.
Consumer Complaining Behavior: The Case of a South American Country, Chile
Authors: Valenzuela Fredy , Pearson David , Epworth Roger , Llanos Orlando , Vilches Sonia
Published: September 2015

Complaining behaviour is a topic that has not been studied much in South America. Considering this, the aim of this investigation was to determine the customers complaining behaviour of a South American country, Chile. To do so, a survey was done, which was applied to a random sample of 498 Chileans. Results show that Chileans do not consider complaining as a right, they have a regular opinion of the way companies are handling complaints, and that the product characteristics is the dimension that has the biggest influence on their complaining behaviour. In addition those Chilean consumers who have complained in the past have a more positive attitude toward complaining than those who have never done it.
Technological Innovativeness and Organizational Culture in Hong Kong
Authors: Wong Gary Y. F. , Fung Richard Y. K.
Published: September 2015

This paper attempts to explore the relationship between technological innovativeness and organizational culture in Hong Kong. It measures both technical and administrative innovations status of organizations. A questionnaire survey is conducted to collect information from various industries in Hong Kong. Also included is the temporal information of innovations. The research uses path analysis to measure the impacts of three organizational factors on innovativeness. Organizational characteristics, organizational climate and organizational context are the factors that used in the research. As shown in the research, learning ability, centralization, specialization, external orientation, formalization, sufficient slack, achievement orientation and risk orientation are influencing the innovativeness in various perspectives.
How do organizations implement downsizing? – An Australian and New Zealand study
Authors: Gandolfi Franco
Published: September 2015

The Australian and New Zealand banking industries have been cutting their workforces steadily since the mid-1990s. With further rounds of workforce downsizing predicted, it was of considerable interest and importance to examine the implementation strategies that large Australian and New Zealand banks have adopted in their latest downsizing endeavors. This study has revealed three major findings. First, Australian banks tended to primarily adopt workforce reduction strategies, whereas New Zealand banks employed a mixture of organization redesign strategies, workforce reduction strategies, and systemic strategies. Second, Australian banks were perceived to have considerable depth in their downsizing, whereas New Zealand banks had more breadth in their overall strategies. Third, Australian banks favored to adopt reorientation approaches, whereas New Zealand banks were more inclined to embrace reinforcement (convergence) approaches. It remains unclear as to why large Australian and New Zealand banks have diverged in their approaches and strategies to downsizing and in their differing selection of available implementation strategies. Government interference, executive remuneration, industrial relations demands, competitive national and international market pressures, and the downsizing history of individual industries and organizations, on the one hand, and differences in national cultures and cultural values on the other, may have influenced the adoption of downsizing implementation strategies. At the same time, it has also been shown that downsizing has engendered negative financial, organizational, and social consequences in both Australia and New Zealand.
The Role of Personality Traits in UTAUT Model under Online Stocking
Authors: Wang Hsing-I , Yang Heng-Li
Published: September 2015

The introduction of a new science and technology will fully reflect its value and its potential to create value only when individuals are willing to accept and adopt it in their daily works. The theory of acceptance and use of new technology has been widely discussed for decades and is still attracting scholars to work toward developing a comprehensive model. The reasons are because of various latent variables that might affect the model, and moreover, the way how the variables interfere the model has not reached an agreement. This research combines the theory of personality traits with the unified theory of acceptance and use of technology. The purposes are to examine the roles that personality traits play in UTAUT model under the context of online stocking.
IT—Enabled Supply Chain Management
Authors: Salo Jari , Karjaluoto Heikki
Published: September 2015

Supply chain management and information technology are two areas of research, which have attracted a lot of attention in academic and practitioner’s camps over the last decades. The discussion related to the deployment of information technology and electronic commerce in supply chain management has fostered a discussion about information technology enabled supply chains. The authors pinpoint, there is a lack of research which integrates this highly inconsistent and fragmented field. In this paper, the authors attempt to present a critical summary of the discussion of information technology enabled supply chain and supply chain management and attempt to provide a framework that helps managers and practitioners to tackle this phenomenon. It can be stated that management of information technology enabled supply chain is a complex process and that top managerial support is always welcome. Finally, we present limitations of the study and highlight some ideas for future research in this area.

Keywords: Marketing, supply chain management, information technology
The Use of Secondary Data in Unveiling the Potential of Ethnic Markets
Authors: Chan Alvin M. , Ahmed Farid
Published: September 2015

While there is an increasing number of companies realizing the potential that the diverse ethnic markets in Australia possess, majority still do not see the potential. When compared to the United States, ethnic marketing in Australia is still in a developmental stage. For many marketers, the problem is in knowing where to start. Looking from the practitioner’s perspective, this paper demonstrates how to apply readily available secondary data in identifying the potential of the ethnic markets in Australia for selected goods and services. By showing where and how to start, we hope that more marketers in Australia will see the potential of ethnic marketing and in the long run ethnic marketing will be an integral part of any marketing campaign run by a company. Marketers should reassess the usefulness and importance of secondary data in facilitating their formulation of strategic marketing decisions in different marketing mix areas.
Can a School Organization be Transformed into a Learning Organization?
Authors: Gandolfi Franco
Published: September 2015

Organizations that have transformed into Learning Organizations have a strong tendency to focus upon continuous improvement and have the ability to cope with major change more successfully and effectively. The concept of the Learning Organization is not confined to a particular type, size, and form of organization, and also includes school organizations. Empirical and anecdotal evidence suggests that little research on school organization as Learning Organizations has been conducted and documented. It has been shown that there is currently no Taiwanese school organization at any level that claims to have become a genuine Learning Organization. This research paper presents an analysis of selected Learning Organization methodologies that are deemed to be effective in assisting in the process of transforming a school organization into a Learning Organization – business process reengineering (BPR), dialogue, scenario analysis, and learning histories. It also reviews various Learning Organization improvement models and models of educational cultural change and learning. The paper proposes a blueprint to transform school organizations into Learning Organizations – the “Learning Organization model for school organizations”.
Controls on biogenic silica burial in the Southern Ocean
Authors: Chase Zanna , Kohfeld Karen E. , Matsumoto Katsumi
Published: September 2015

Understanding the controls on opal export in the Southern Ocean can inform both the prediction of how the leakage of silicic acid from the Southern Ocean responds to climate and the interpretation of paleo‐proxies. We have compiled a database of 185 230Thorium‐normalized opal burial rates and 493 opal concentration measurements in Southern Ocean sediments and matched these with environmental climatologies. By subdividing the Southern Ocean on the basis of oceanographic regions and interpolating the opal burial rates, we estimate a total biogenic Si burial south of 40°S of 2.3 ± 1.0 Tmol Si yr−1. In both the seasonally ice‐covered and permanently ice‐free regions we can explain 73% of opal burial variability from surface ocean properties. Where sea ice is present for at least part of the year, the length of the ice‐free season determines the upper limit of opal burial in the underlying sediments. In the ice‐free regions of the Southern Ocean, the supply of silicic acid through winter mixing is the most important factor. Our results do not support a strong role of iron in controlling opal burial. We do however find that satellite‐derived net primary production increases with increasing (modeled) dust delivery. These findings support the decoupling between carbon and opal fluxes in the Southern Ocean. When corrected for opal dissolution, the observed opal fluxes are in reasonable agreement with fluxes simulated using an ocean biogeochemical model. However, the results suggest current preservation algorithms for opal could be improved by incorporating the composition of particle flux, not only its magnitude.
Quantitative estimates of Asian dust input to the western Philippine Sea in the mid‐late Quaternary and its potential significance for paleoenvironment
Authors: Xu Zhaokai , Li Tiegang , Clift Peter D. , Lim Dhongil , Wan Shiming , Chen Hongjin , Tang Zheng , Jiang Fuqing , Xiong Zhifang
Published: September 2015

We present a new high‐resolution multiproxy data set of Sr‐Nd isotopes, rare earth element, soluble iron, and total organic carbon data from International Marine Global Change Study Core MD06‐3047 located in the western Philippine Sea. We integrate our new data with published clay mineralogy, rare earth element chemistry, thermocline depth, and δ13C differences between benthic and planktonic foraminifera, in order to quantitatively constrain Asian dust input to the basin. We explore the relationship between Philippine Sea and high‐latitude Pacific eolian fluxes, as well as its significance for marine productivity and atmospheric CO2 during the mid‐late Quaternary. Three different indices indicate that Asian dust contributes between ∼15% and ∼50% to the detrital fraction of the sediments. Eolian dust flux in Core MD06‐3047 is similar to that in the polar southern Pacific sediment. Coherent changes for most dust flux maximum/minimum indicate that dust generation in interhemispheric source areas might have a common response to climatic variation over the mid‐late Quaternary. Furthermore, we note relatively good coherence between Asian dust input, soluble iron concentration, local marine productivity, and even global atmospheric CO2 concentration over the entire study interval. This suggests that dust‐borne iron fertilization of marine phytoplankton might have been a periodic process operating at glacial/interglacial time scales over the past 700 ka. We suggest that strengthening of the biological pump in the Philippine Sea, and elsewhere in the tropical western Pacific during the mid‐late Quaternary glacial periods may contribute to the lowering of atmospheric CO2 concentrations during ice ages.
Erosion patterns and mantle sources of topographic change across the southern African Plateau derived from the shallow and deep records of kimberlites
Authors: Stanley Jessica R. , Flowers Rebecca M. , Bell David R.
Published: September 2015

Flow in the sublithospheric mantle is increasingly invoked as a mechanism to explain both modern and past surface topography, but the importance of this phenomenon and its influence at different localities are debated. Southern Africa is an elevated continental shield proposed to represent dynamically supported topography. However, this region is also characterized by a complex lithospheric architecture variably affected by Cretaceous heating, thinning, and metasomatic alteration. We used apatite (U‐Th)/He thermochronometry on 15 Cretaceous kimberlites from an ∼600 km long transect across the Kaapvaal Craton, combined with information from xenoliths in these pipes, to determine the plateau interior erosion history. The goal was to determine the relationships with lithospheric modification patterns and thereby better isolate the sublithospheric contribution to elevation. The results document a wave of erosion from west to east across the craton from ∼120 to <60 Ma, initially focused along paleorivers and then retreating as a scarp across the landscape. This spatially variable erosion event was associated with limited modification of the Archean cratonic lithospheric mantle as recorded by mantle xenoliths and xenocrysts, implying that dynamic buoyancy sources may be required to explain the elevations. In contrast, off‐craton to the southwest, a more pronounced regional erosion phase at ∼110–90 Ma was coincident with significant modification of the Proterozoic lithospheric mantle. This relationship suggests that lithospheric processes were more important contributors to erosion and topographic change off‐craton than on‐craton. Together, these results suggest that lithospheric architecture can have an important control on the surface expression of mantle dynamics.
Late Miocene to recent plate tectonic history of the southern Central America convergent margin
Authors: Morell Kristin D.
Published: September 2015

New plate reconstructions constrain the tectonic evolution of the subducting Cocos and Nazca plates across the southern Central American subduction zone from late Miocene to recent. Because of the strong relationships between lower and upper (Caribbean) plate dynamics along this margin, these constraints have wide‐ranging implications for the timing and growth of upper plate deformation and volcanism in southern Central America. The reconstructions outline three important events in the Neogene history of this margin: (1) the coeval development of the Panama Triple Junction with the initiation of oblique subduction of the Nazca plate at ∼8.5 Ma; (2) the initiation of seamount and rough crust subduction beginning at ∼3–4 Ma; and (3) Cocos Ridge subduction from ∼2 to 3 Ma. A comparison of these events with independent geologic, geomorphic, volcanic, and stratigraphic data sets reveals that the timing, rates, and origin of subducting crust directly impacted the Neogene growth of upper plate deformation and volcanism in southern Central America. These analyses constrain the timing, geometry, and causes of a number of significant tectonic and volcanic processes, including rapid Plio‐Quaternary arc‐fore arc contraction due to Cocos Ridge subduction, the detachment of the Panama microplate at ∼1–3 Ma, and the late Miocene cessation of mantle‐wedge‐derived volcanism across ∼300 km of the subduction zone.
Toward the reconciliation of seismological and petrological perspectives on oceanic lithosphere heterogeneity
Authors: Kennett B. L. N. , Furumura T.
Published: September 2015

The character of the high‐frequency seismic phases Po and So, observed after propagation for long distances in the oceanic lithosphere, requires the presence of scattering from complex structure in 3‐D. Current models use stochastic representations of seismic structure in the oceanic lithosphere. The observations are compatible with quasi‐laminate features with horizontal correlation length around 10 km and vertical correlation length 0.5 km, with a uniform level of about 2% variation through the full thickness of the lithosphere. Such structures are difficult to explain with petrological models, which would favor stronger heterogeneity at the base of the lithosphere associated with underplating from frozen melts. Petrological evidence mostly points to smaller‐scale features than suggested by seismology. The models from the different fields have been derived independently, with various levels of simplification. Fortunately, it is possible to gently modify the seismological model toward stronger basal heterogeneity, but there remains a need for some quasi‐laminate structure throughout the mantle component of the oceanic lithosphere. The new models help to bridge the gulf between the different viewpoints, but ambiguities remain.
A statistical survey of reconnection exhausts in the solar wind based on the Riemannian decay of current sheets
Authors: Sasunov Yu. L. , Semenov V. S. , Heyn M. F. , Erkaev N. V. , Kubyshkin I. V. , Slivka K. Yu. , Korovinskiy D. B. , Khodachenko M. L.
Published: September 2015

We present a statistical study of the magnetic reconnection exhausts in solar wind. Observational data are compared with the analytical model based on the Riemann analysis of tangential discontinuity decay forced by finite X‐line reconnection of skewed magnetic fields. Statistical analysis is based on 51 events of the solar wind reconnection listed in Phan et al. (2009). The best agreement of the observed and analytically predicted values is achieved for the rotational angle of the tangential magnetic field component with correlation coefficient reaching the value of 0.97. The lowest correlation coefficient of 0.87 is obtained for the exhaust flow plasma temperature. It is found that proton temperature increases at the exhaust boundary while electron temperature stays unchanged. This may indicate that heating and acceleration processes operate on the proton scale. Exhaust boundaries are identified as tangential discontinuities, except one particular event, where Alfvén discontinuity and slow shock were detected instead. Hence, the impulsive reconnection may be supposed in that case rather than steady state one. Exhaust regions extending up to 690RE, registered in some observations, do not necessarily imply X‐lines of similar length. They could be explained alternatively by reconnection of skewed magnetic fields. The numerical modeling of the interplanetary coronal mass ejection (ICME) propagating in the solar wind reveals that the resistance force, impeding the ICME motion, may be reduced significantly (three times in our simulations) by means of the magnetic reconnection at the leading edge. Thus, reconnection may substantially increase ICME velocity and travel distance.
Excitation of dayside chorus waves due to magnetic field line compression in response to interplanetary shocks
Authors: Zhou Chen , Li Wen , Thorne Richard M. , Bortnik Jacob , Ma Qianli , An Xin , Zhang Xiao‐jia , Angelopoulos Vassilis , Ni Binbin , Gu Xudong , Fu Song , Zhao Zhengyu
Published: September 2015

The excitation of magnetospheric whistler‐mode chorus in response to interplanetary (IP) shocks is investigated using wave data from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) spacecraft. As an example, we show a typical chorus wave excitation following an IP shock event that was observed by THEMIS in the postnoon sector near the magnetopause on 3 August 2010. We then analyze characteristic changes during this event and perform a survey of similar events during the period 2008–2014 using the THEMIS and OMNI data set. Our statistical analysis demonstrates that the chorus wave excitation/intensification in response to IP shocks occurs only at high L shells (L > 8) on the dayside. We analyzed the variations of magnetic curvature following the arrival of the IP shock and found that IP shocks lead to more homogeneous background magnetic field configurations in the near‐equatorial dayside magnetosphere; and therefore, the threshold of nonlinear chorus wave growth is likely to be reduced, favoring chorus wave generation. Our results provide the observational evidence to support the concept that the geomagnetic field line configuration plays a key role in the excitation of dayside chorus.
Quantifying hydrate solidification front advancing using method of characteristics
Authors: You Kehua , DiCarlo David , Flemings Peter B.
Published: September 2015

We develop a one‐dimensional analytical solution based on the method of characteristics to explore hydrate formation from gas injection into brine‐saturated sediments within the hydrate stability zone. Our solution includes fully coupled multiphase and multicomponent flow and the associated advective transport in a homogeneous system. Our solution shows that hydrate saturation is controlled by the initial thermodynamic state of the system and changed by the gas fractional flow. Hydrate saturation in gas‐rich systems can be estimated by
when Darcy flow dominates, where cl0 is the initial mass fraction of salt in brine, and cle is the mass fraction of salt in brine at three‐phase (gas, liquid, and hydrate) equilibrium. Hydrate saturation is constant, gas saturation and gas flux decrease, and liquid saturation and liquid flux increase with the distance from the gas inlet to the hydrate solidification front. The total gas and liquid flux is constant from the gas inlet to the hydrate solidification front and decreases abruptly at the hydrate solidification front due to gas inclusion into the hydrate phase. The advancing velocity of the hydrate solidification front decreases with hydrate saturation at a fixed gas inflow rate. This analytical solution illuminates how hydrate is formed by gas injection (methane, CO2, ethane, propane) at both the laboratory and field scales.
Acoustic signals generated in inclined granular flows
Authors: Tan Danielle S. , Jenkins James T. , Keast Stephen C. , Sachse Wolfgang H.
Published: September 2015

Spontaneous avalanching in specific deserts produces a low‐frequency sound known as “booming.” This creates a puzzle, because avalanches down the face of a dune result in collisions between sand grains that occur at much higher frequencies. Reproducing this phenomenon in the laboratory permits a better understanding of the underlying mechanisms for the generation of such lower frequency acoustic emissions, which may also be relevant to other dry granular flows. Here we report measurements of low‐frequency acoustical signals, produced by dried “sounding” sand (sand capable of booming in the desert) flowing down an inclined chute. The amplitude of the signal diminishes over time but reappears upon drying of the sand. We show that the presence of this sound in the experiments may provide supporting evidence for a previously published “waveguide” explanation for booming. Also, we propose a model based on kinetic theory for a sheared inclined flow in which the flowing layer exhibits “breathing” modes superimposed on steady shearing. The predicted oscillation frequency is of a similar order of magnitude as the measurements, indicating that small perturbations can sustain oscillations of a low frequency. However, the frequency is underestimated, which indicates that the stiffness has been underestimated. Also, the model predicts a discrete spectrum of frequencies, instead of the broadband spectrum measured experimentally.
Multi‐instrument, high‐resolution imaging of polar cap patch transportation
Authors: Thomas E. G. , Hosokawa K. , Sakai J. , Baker J. B. H. , Ruohoniemi J. M. , Taguchi S. , Shiokawa K. , Otsuka Y. , Coster A. J. , St.‐Maurice J.‐P. , McWilliams K. A.
Published: September 2015

Transionospheric radio signals in the high‐latitude polar cap are susceptible to degradation when encountering sharp electron density gradients associated with discrete plasma structures, or patches. Multi‐instrument measurements of polar cap patches are examined during a geomagnetic storm interval on 22 January 2012. For the first time, we monitor the transportation of patches with high spatial and temporal resolution across the polar cap for 1–2 h using a combination of GPS total electron content (TEC), all‐sky airglow imagers (ASIs), and Super Dual Auroral Radar Network (SuperDARN) HF radar backscatter. Simultaneous measurements from these data sets allow for continuous tracking of patch location, horizontal extent, and velocity despite adverse observational conditions for the primary technique (e.g., sunlit regions in the ASI data). Spatial collocation between patch‐like features in relatively coarse but global GPS TEC measurements and those mapped by high‐resolution ASI data was very good, indicating that GPS TEC can be applied to track patches continuously as they are transported across the polar cap. In contrast to previous observations of cigar‐shaped patches formed under weakly disturbed conditions, the relatively narrow dawn‐dusk extent of patches in the present interval (500–800 km) suggests association with a longitudinally confined plasma source region, such as storm‐enhanced density (SED) plume. SuperDARN observations show that the backscatter power enhancements corresponded to the optical patches, and for the first time we demonstrate that the motion of the optical patches was consistent with background plasma convection velocities.
Total Synthesis and Neuritogenic Activity Evaluation of Ganglioside PNG‐2A from the Starfish Protoreaster nodosus
Authors: Goto Kenta , Suzuki Tatsuya , Tamai Hideki , Ogawa Junya , Imamura Akihiro , Ando Hiromune , Ishida Hideharu , Kiso Makoto
Published: September 2015

The total synthesis of ganglioside PNG‐2A from the starfish Protoreaster nodosus and its neuritogenic activity toward neuron‐like cells is described. The unique galactose‐enriched glycan moiety, in which an 8‐O‐methyl sialic acid residue is sandwiched between galactose residues, was constructed through an efficient 8‐O‐methylation and subsequent di‐tert‐butylsilylene‐assisted α‐glycosylation at the 4‐OH of the sialic acid residue with a Galfβ(1,3)Gal donor. In vitro biological evaluation in a rat adrenal pheochromocytoma (PC12) cell line revealed that the synthesized PNG‐2A potentiated the neurite outgrowth of PC12 cells in the presence of nerve growth factor (NGF).
Metall‐Ligand‐Kooperation
Authors: Khusnutdinova Julia R. , Milstein David
Published: September 2015

Die Metall‐Ligand‐Kooperation (MLC) hat sich zu einem wichtigen Konzept in der Übergangsmetallkatalyse in synthetischen und biologischen Systemen entwickelt. MLC bedeutet, dass sowohl das Metall als auch der Ligand direkt an der Bindungsaktivierung beteiligt sind, im Gegensatz zur klassischen Übergangsmetallkatalyse, wo der Ligand (z. B. Phosphan) nur als “Zuschauer” agiert und sämtliche Schlüsseltransformationen am Metallzentrum ablaufen. In diesem Aufsatz diskutieren wir Beispiele von Metall‐Ligand‐Kooperationen, bei denen 1) sowohl das Metall als auch der Ligand im Verlauf der Bindungsaktivierung chemisch modifiziert werden und 2) die Bindungsaktivierung zu unmittelbaren Änderungen in der ersten Koordinationsschale führt, selbst wenn das reaktive Zentrum im Liganden nicht direkt an das Metall bindet. Die Bedeutung der Metall‐Ligand‐Kooperation für effiziente Katalyseprozesse, aber auch für die Katalysatordeaktivierung, wird besprochen.
Synthese und stereochemische Bestimmung von krypto‐optisch‐aktivem 2H6‐Neopentan
Authors: Masarwa Ahmad , Gerbig Dennis , Oskar Liron , Loewenstein Aharon , Reisenauer Hans Peter , Lesot Philippe , Schreiner Peter R. , Marek Ilan
Published: September 2015

Die Bestimmung der absoluten Konfiguration chiraler Molekülen gilt als das Herzstück der asymmetrischen Synthese. Hier untersuchen wir die spektroskopischen Grenzen der chiralen Differenzierung mit NMR‐Spektroskopie in chiral ausrichtenden Medien und mit Schwingungszirkulardichroismus‐Spektroskopie anhand des sechsfach deuterierten chiralen Neopentans. Da dessen Chiralität nur auf kleinen Massenunterschieden beruht, erweist sich die Strukturbestimmung als besonders schwierig. Wir synthetisierten beide Enantiomere des 2H6‐1 getrennt über einen kurzen Weg, der sich vielfach funktionalisierter Intermediate bedient. Die Bestimmung der Konfiguration der Vorstufen von 2H6‐1 erfolgte mithilfe von NMR‐Spektroskopie in chiral ausrichtenden Medien. Trotz der nur sehr geringfügig dichroitischen Beschaffenheit von 1 konnte die endgültige Konfiguration nur durch VCD‐Spektroskopie bestimmt werden. Ab‐initio‐ und Dichtefunktionalrechnungen ermöglichten die eindeutige Zuordnung beider Enantiomere.
Turning Cucurbit[8]uril into a Supramolecular Nanoreactor for Asymmetric Catalysis
Authors: Zheng Lifei , Sonzini Silvia , Ambarwati Masyitha , Rosta Edina , Scherman Oren A. , Herrmann Andreas
Published: September 2015

Chiral macromolecules have been widely used as synthetic pockets to mimic natural enzymes and promote asymmetric reactions. An achiral host, cucurbit[8]uril (CB[8]), was used for an asymmetric Lewis acid catalyzed Diels–Alder reaction. We achieved a remarkable increase in enantioselectivity and a large rate acceleration in the presence of the nanoreactor by using an amino acid as the chiral source. Mechanistic and computational studies revealed that both the amino acid–Cu2+ complex and the dienophile substrate are included inside the macrocyclic host cavity, suggesting that contiguity and conformational constraints are fundamental to the catalytic process and rate enhancement. These results pave the way towards new studies on asymmetric reactions catalyzed in confined achiral cavities.
Highly Efficient Near‐Infrared Delayed Fluorescence Organic Light Emitting Diodes Using a Phenanthrene‐Based Charge‐Transfer Compound
Authors: Wang Shipan , Yan Xianju , Cheng Zong , Zhang Hongyu , Liu Yu , Wang Yue
Published: September 2015

Significant efforts have been made to develop high‐efficiency organic light‐emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) emitters with blue, green, yellow, and orange–red colors. However, efficient TADF materials with colors ranging from red, to deep‐red, to near‐infrared (NIR) have been rarely reported owing to the difficulty in molecular design. Herein, we report the first NIR TADF molecule TPA‐DCPP (TPA=triphenylamine; DCPP=2,3‐dicyanopyrazino phenanthrene) which has a small singlet–triplet splitting (ΔEST) of 0.13 eV. Its nondoped OLED device exhibits a maximum external quantum efficiency (EQE) of 2.1 % with a Commission International de L′Éclairage (CIE) coordinate of (0.70, 0.29). Moreover, an extremely high EQE of nearly 10 % with an emission band at λ=668 nm has been achieved in the doped device, which is comparable to the most‐efficient deep‐red/NIR phosphorescent OLEDs with similar electroluminescent spectra.
Formation of Frustrated Lewis Pairs in Ptx‐Loaded Zeolite NaY
Authors: Lee Heeju , Choi Yong Nam , Lim Dae‐Woon , Rahman Md. Mahbubur , Kim Yong‐Il , Cho In Hwa , Kang Hyun Wook , Seo Jung‐Hye , Jeon Cheolho , Yoon Kyung Byung
Published: September 2015

The formation of a frustrated Lewis pair consisting of sodium hydride (Na+H−) and a framework‐bound hydroxy proton O(H+) is reported upon H2 treatment of zeolite NaY loaded with Pt nanoparticles (Ptx/NaY). Frustrated Lewis pair formation was confirmed using in situ neutron diffraction and spectroscopic measurements. The activity of the intrazeolite NaH as a size‐selective catalyst was verified by the efficient esterification of acetaldehyde (a small aldehyde) to form the corresponding ester ethyl acetate, whereas esterification of the larger molecule benzaldehyde was unsuccessful. The frustrated Lewis pair (consisting of Na+H− and O(H+)) generated within zeolite NaY may be a useful catalyst for various catalytic reactions which require both H− and H+ ions, such as catalytic hydrogenation or dehydrogenation of organic compounds and activation of small molecules.
Reversible Photoswitching of a Spin‐Crossover Molecular Complex in the Solid State at Room Temperature
Authors: Rösner Benedikt , Milek Magdalena , Witt Alexander , Gobaut Benoît , Torelli Piero , Fink Rainer H. , Khusniyarov Marat M.
Published: September 2015

Spin‐crossover metal complexes are highly promising magnetic molecular switches for prospective molecule‐based devices. The spin‐crossover molecular photoswitches developed so far operate either at very low temperatures or in the liquid phase, which hinders practical applications. Herein, we present a molecular spin‐crossover iron(II) complex that can be switched between paramagnetic high‐spin and diamagnetic low‐spin states with light at room temperature in the solid state. The reversible photoswitching is induced by alternating irradiation with ultraviolet and visible light and proceeds at the molecular level.
A Low‐Valent Iron Imido Heterocubane Cluster: Reversible Electron Transfer and Catalysis of Selective C–C Couplings
Authors: Lichtenberg Crispin , Garcia Rubio Inés , Viciu Liliana , Adelhardt Mario , Meyer Karsten , Jeschke Gunnar , Grützmacher Hansjörg
Published: September 2015

Enzymes and cofactors with iron–sulfur heterocubane core structures, [Fe4S4], are often found in nature as electron transfer reagents in fundamental catalytic transformations. An artificial heterocubane with a [Fe4N4] core is reported that can reversibly store up to four electrons at very negative potentials. The neutral [Fe4N4] and the singly reduced low‐valent [Fe4N4]− heterocubanes were isolated and fully characterized. The low‐valent species bears one unpaired electron, which is localized predominantly at one iron center in the electronic ground state but fluctuates with increasing temperatures. The electrons stored or released by the [Fe4N4]/[Fe4N4]− redox couple can be used in reductive or oxidative CC couplings and even allow catalytic one‐pot reactions, which show a remarkably enhanced selectivity in the presence of the [Fe4N4] heterocubanes.
A Photonic Crystal Protein Hydrogel Sensor for Candida albicans
Authors: Cai Zhongyu , Kwak Daniel H. , Punihaole David , Hong Zhenmin , Velankar Sachin S. , Liu Xinyu , Asher Sanford A.
Published: September 2015

We report two‐dimensional (2D) photonic crystal (PC) sensing materials that selectively detect Candida albicans (C. albicans). These sensors utilize Concanavalin A (Con A) protein hydrogels with a 2D PC embedded on the Con A protein hydrogel surface, that multivalently and selectively bind to mannan on the C. albicans cell surface to form crosslinks. The resulting crosslinks shrink the Con A protein hydrogel, reduce the 2D PC particle spacing, and blue‐shift the light diffracted from the PC. The diffraction shifts can be visually monitored, measured with a spectrometer, or determined from the Debye diffraction ring diameter. Our unoptimized hydrogel sensor has a detection limit of around 32 CFU/mL for C. albicans. This sensor distinguishes between C. albicans and those microbes devoid of cell‐surface mannan such as the gram‐negative bacterium E. coli. This sensor provides a proof‐of‐concept for utilizing recognition between lectins and microbial cell surface carbohydrates to detect microorganisms in aqueous environments.
Rhodium(III)‐Catalyzed Amidation of Unactivated C(sp3)H Bonds
Authors: Wang He , Tang Guodong , Li Xingwei
Published: September 2015

Nitrogenation by direct functionalization of CH bonds represents an important strategy for constructing CN bonds. Rhodium(III)‐catalyzed direct amidation of unactivated C(sp3)H bonds is rare, especially under mild reaction conditions. Herein, a broad scope of C(sp3)H bonds are amidated under rhodium catalysis in high efficiency using 3‐substituted 1,4,2‐dioxazol‐5‐ones as the amide source. The protocol broadens the scope of rhodium(III)‐catalyzed C(sp3)H activation chemistry, and is applicable to the late‐stage functionalization of natural products.
Rhodium(II) Proximity‐Labeling Identifies a Novel Target Site on STAT3 for Inhibitors with Potent Anti‐Leukemia Activity
Authors: Minus Matthew B. , Liu Wei , Vohidov Farrukh , Kasembeli Moses M. , Long Xin , Krueger Michael J. , Stevens Alexandra , Kolosov Mikhail I. , Tweardy David J. , Sison Edward Allan R. , Redell Michele S. , Ball Zachary T.
Published: September 2015

Nearly 40 % of children with acute myeloid leukemia (AML) suffer relapse arising from chemoresistance, often involving upregulation of the oncoprotein STAT3 (signal transducer and activator of transcription 3). Herein, rhodium(II)‐catalyzed, proximity‐driven modification identifies the STAT3 coiled‐coil domain (CCD) as a novel ligand‐binding site, and we describe a new naphthalene sulfonamide inhibitor that targets the CCD, blocks STAT3 function, and halts its disease‐promoting effects in vitro, in tumor growth models, and in a leukemia mouse model, validating this new therapeutic target for resistant AML.
Asymmetric Synthesis of Hydrocarbazoles Catalyzed by an Octahedral Chiral‐at‐Rhodium Lewis Acid
Authors: Huang Yong , Song Liangliang , Gong Lei , Meggers Eric
Published: September 2015

A bis‐cyclometalated chiral‐at‐metal rhodium complex catalyzes the Diels–Alder reaction between N‐Boc‐protected 3‐vinylindoles (Boc=tert‐butyloxycarbonyl) and β‐carboxylic ester‐substituted α,β‐unsaturated 2‐acyl imidazoles with good‐to‐excellent regioselectivity (up to 99:1) and excellent diastereoselectivity (>50:1 d.r.) as well as enantioselectivity (92–99 % ee) under optimized conditions. The rhodium catalyst serves as a chiral Lewis acid to activate the 2‐acyl imidazole dienophile by two‐point binding and overrules the preferred regioselectivity of the uncatalyzed reaction.
Pragmatic staging of oesophageal cancer using decision theory involving selective endoscopic ultrasonography, PET and laparoscopy
Authors: Findlay J M , Bradley K M , Maile E J , Braden B , Maw J , Phillips-Hughes J , Gillies R S , Maynard N D , Middleton M R
Published: September 2015

Background

Following CT, guidelines for staging oesophageal and gastro-oesophageal junction (GOJ) cancer recommend endoscopic ultrasonography (EUS), PET–CT and laparoscopy for T3–T4 GOJ tumours. These recommendations are based on generic utilities, but it is unclear whether the test risk outweighs the potential benefit for some patients. This study sought to quantify investigation risks, benefits and utilities, in order to develop pragmatic, personalized staging recommendations.

Methods

All patients with a histological diagnosis of oesophageal or GOJ cancer staged between May 2006 and July 2013 comprised a development set; those staged from July 2013 to July 2014 formed the prospective validation set. Probability thresholds of altering management were calculated and predictive factors identified. Algorithms and models (decision tree analysis, logistic regression, artificial neural networks) were validated internally and independently.

Results

Some 953 patients were staged following CT, by [18F]fluorodeoxyglucose PET–CT (918), EUS (798) and laparoscopy (458). Of these patients, 829 comprised the development set (800 PET–CT, 698 EUS, 397 laparoscopy) and 124 the validation set (118 PET–CT, 100 EUS, 61 laparoscopy). EUS utility in the 71·8 per cent of patients with T2–T4a disease on CT was minimal (0·4 per cent), its risk exceeding benefit. EUS was moderately accurate for pT1 N0 disease. A number of factors predicted metastases on PET–CT and laparoscopy, although none could inform an algorithm. PET–CT altered management in 23·0 per cent, and laparoscopy in 7·1 per cent, including those with T2 and distal oesophageal tumours.

Conclusion

Although EUS provided additional information on T and N category, its risk outweighed potential benefit in patients with T2–T4a disease on CT. Laparoscopy seemed justified for distal oesophageal tumours of T2 or greater.
Successful treatment of fetal hemolytic disease due to glucose phosphate isomerase deficiency (GPI) using repeated intrauterine transfusions: a case report
Authors: Adama van Scheltema Phebe N. , Zhang Ai , Ball Lynne M. , Steggerda Sylke J. , van Wijk Richard , Fransen van de Putte Dietje E. , van Kamp Inge L.
Published: September 2015

Key Clinical Message

Hemolytic anemia due to GPI deficiency can be severe and life threatening during fetal life. When parents decline invasive testing, ultrasound monitoring of fetuses at risk is feasible. Intrauterine transfusion can be effective for the treatment of severe fetal anemia due to GPI deficiency.
Congenital isolated Iso–Kikuchi syndrome in a newborn
Authors: Valerio Enrico , Favot Francesca , Mattei Ilaria , Cutrone Mario
Published: September 2015

Key Clinical Message

Classic CO (also called Iso–Kikuchi syndrome) represents a benign, isolated condition associated with normal patient outcome. Nevertheless, clinical follow‐up and/or further clinically‐based tests are needed to exclude other nail diseases associated with multisystem pathology; complete family history is also important to determine sporadic or hereditary transmission of such condition.
Nonsurgical management of multiple splenic abscesses in an obese patient that underwent laparoscopic sleeve gastrectomy: case report and review of literature
Authors: Schiavo Luigi , Scalera Giuseppe , De Sena Gabriele , Ciorra Francesca R. , Pagliano Pasquale , Barbarisi Alfonso
Published: September 2015

Key Clinical Message

Sleeve gastrectomy (SG) is a surgical weight‐loss procedure. Splenic abscess is a rare complication of SG. Four cases of splenic abscess after SG have been reported, all managed by surgical intervention. We report the first documented case of multiple splenic abscesses following SG managed conservatively by an integrated medical treatment.