bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal tides during the 2001 Martian global‐scale dust storm
Authors: Guzewich Scott D. , Wilson R. John , McConnochie Timothy H. , Toigo Anthony D. , Banfield Donald J. , Smith Michael D. 
Published: February 2014

AbstractThe 2001 (Mars Year 25) global dust storm radically altered the dynamics of the Martian atmosphere. Using observations from the Thermal Emission Spectrometer onboard the Mars Global Surveyor spacecraft and MarsWRF general circulation model simulations, we examine the changes to thermal tides and planetary waves caused by the storm. We find that the extratropical diurnal migrating tide is dramatically enhanced during the storm, particularly in the southern hemisphere, reaching amplitudes of more than 20 K. The tropical diurnal migrating tide is weakened to almost undetectable levels. The diurnal Kelvin waves are also significantly weakened, particularly during the period of global expansion at Ls = 200°–210°. In contrast, the westward propagating diurnal wavenumber 2 tide strengthens to 4–8 K at altitudes above 30 km. The wavenumber 1 stationary wave reaches amplitudes of 10–12 K at 50°–70°N, far larger than is typically seen during this time of year. The phase of this stationary wave and the enhancement of the diurnal wavenumber 2 tide appear to be responses to the high‐altitude westward propagating equatorial wavenumber 1 structure in dust mixing ratio observed during the storm in previous works. This work provides a global picture of dust storm wave dynamics that reveals the coupling between the tropics and high‐latitude wave responses. We conclude that the zonal distribution of thermotidal forcing from atmospheric aerosol concentration is as important to understanding the atmospheric wave response as the total global mean aerosol optical depth.
Carbon release from boreal peatland open water pools: Implication for the contemporary C exchange
Authors: Pelletier Luc , Strachan Ian B. , Garneau Michelle , Roulet Nigel T. 
Published: February 2014

AbstractWhile peatland ecosystems overall are long‐term net carbon (C) sinks, the open water pools that are characteristic of boreal peatlands have been found to be C sources to the atmosphere. However, the contribution of these pools to the ecosystem level C budget is often ignored even if they cover a significant area of the peatland surface. Here we examine the annual CO2 and CH4 ecosystem‐atmosphere exchange, including the release following ice melt, from pools in a boreal maritime peatland, in order to estimate the annual loss of C from these water bodies. Over a 16 month period, dissolved CO2 and CH4 were measured periodically in five pools while continuous measurements of CO2 were made in one pool using a nondispersive infrared (NDIR) sensor. Fluxes were calculated using the thin boundary layer model and the eddy covariance technique (spring release only). We calculated an annual C release from pools of 103.3 g C m−2 yr−1 of which 15% was released during the spring ice melt. This release is the same order of magnitude, but with the opposite sign, as the average net ecosystem carbon balance for pool‐free northern peatlands (−22 to −70 g C m−2 yr−1). We discuss the origin of the released C, as the magnitude of the release could have a significant impact on the contemporary C exchange of boreal peatlands.
Comparison of joint versus postprocessor approaches for hydrological uncertainty estimation accounting for error autocorrelation and heteroscedasticity
Authors: Evin Guillaume , Thyer Mark , Kavetski Dmitri , McInerney David , Kuczera George 
Published: February 2014

AbstractThe paper appraises two approaches for the treatment of heteroscedasticity and autocorrelation in residual errors of hydrological models. Both approaches use weighted least squares (WLS), with heteroscedasticity modeled as a linear function of predicted flows and autocorrelation represented using an AR(1) process. In the first approach, heteroscedasticity and autocorrelation parameters are inferred jointly with hydrological model parameters. The second approach is a two‐stage “postprocessor” scheme, where Stage 1 infers the hydrological parameters ignoring autocorrelation and Stage 2 conditionally infers the heteroscedasticity and autocorrelation parameters. These approaches are compared to a WLS scheme that ignores autocorrelation. Empirical analysis is carried out using daily data from 12 US catchments from the MOPEX set using two conceptual rainfall‐runoff models, GR4J, and HBV. Under synthetic conditions, the postprocessor and joint approaches provide similar predictive performance, though the postprocessor approach tends to underestimate parameter uncertainty. However, the MOPEX results indicate that the joint approach can be nonrobust. In particular, when applied to GR4J, it often produces poor predictions due to strong multiway interactions between a hydrological water balance parameter and the error model parameters. The postprocessor approach is more robust precisely because it ignores these interactions. Practical benefits of accounting for error autocorrelation are demonstrated by analyzing streamflow predictions aggregated to a monthly scale (where ignoring daily‐scale error autocorrelation leads to significantly underestimated predictive uncertainty), and by analyzing one‐day‐ahead predictions (where accounting for the error autocorrelation produces clearly higher precision and better tracking of observed data). Including autocorrelation into the residual error model also significantly affects calibrated parameter values and uncertainty estimates. The paper concludes with a summary of outstanding challenges in residual error modeling, particularly in ephemeral catchments.
Complete seismic release of tectonic strain and earthquake recurrence in the Apennines (Italy)
Authors: D'Agostino N. 
Published: February 2014

AbstractHere I compare estimates of tectonic strain rates from dense Global Positioning System measurements with the seismicity released in the last ~500 years in the Apennines (Italy). The rates of seismic moment accumulation from geodesy and of historical seismic release by earthquakes agree within the uncertainties, ruling out significant aseismic deformation. Within the considered 400 km long section of the Apennines, this balance yields an average recurrence interval of 30–75 years forMW≥6.5 events without requiring a future earthquake larger than those observed historically (MW~7). A minimum estimate of unreleased strain allowsMW≥6.5 andMW≥6.9 events to be released in ~35%and ~10%of the central‐southern Apennines, respectively. The definition of the seismic potential for smaller events is more uncertain, and their occurrence remains a significant threat throughout the Apennines.
A GRACE‐based water storage deficit approach for hydrological drought characterization
Authors: Thomas Alys C. , Reager John T. , Famiglietti James S. , Rodell Matthew 
Published: February 2014

AbstractWe present a quantitative approach for measuring hydrological drought occurrence and severity based on terrestrial water storage observations from NASA's Gravity Recovery and Climate Experiment (GRACE) satellite mission. GRACE measurements are applied by calculating the magnitude of the deviation of regional, monthly terrestrial water storage anomalies from the time series' monthly climatology, where negative deviations represent storage deficits. Monthly deficits explicitly quantify the volume of water required to return to normal water storage conditions. We combine storage deficits with event duration to calculate drought severity. Drought databases are referenced to identify meteorological drought events in the Amazon and Zambezi River basins and the southeastern United States and Texas regions. This storage deficit method clearly identifies hydrological drought onset, end, and duration; quantifies instantaneous severity and peak drought magnitude; and compares well with the meteorological drought databases. It also reveals information about the hydrological effects of meteorological drought on regional water storage.
Eye Movements Indicate the Temporal Organisation of Information Processing in Graph Comprehension
Authors: Körner Christof , Höfler Margit , Tröbinger Barbara , Gilchrist Iain D. 
Published: February 2014

SummaryHierarchical graphs (e.g. file system browsers and preference trees) represent objects (e.g. files and folders) as graph nodes and relations between them (e.g. sub‐folder relations) as lines. We investigated the temporal organisation of two processes that are necessary for comprehending such graphs—search for the graph nodes and reasoning about their relation. We tracked eye movements to change graphs while participants interpreted them. In Experiment 1, we masked the graph at a time when search processes had finished but reasoning was hypothetically ongoing. We observed a dramatic deterioration in comprehension compared with unmasked graphs. In Experiment 2, we changed the relation between critical graph nodes after search for them had finished, unbeknownst to participants. Participants mostly based their response on the graph as presented after the change. These results suggest that comprehension processes are organised in a sequential manner, an observation that can potentially be applied to the interactive presentation of graphs. Copyright © 2014 John Wiley & Sons, Ltd.
Price Discovery in the Chinese Corn Futures Market, With Comparisons to Soybean Futures
Authors: Yan Yunxian , Reed Michael 
Published: February 2014

ABSTRACTThe Chinese corn futures market is the second largest after the CBOT in terms of trading volume in contracts. In 2012, the trading volume of corn futures was 37 million contracts (or 378 million metric tons). The relationship between Chinese corn futures and spot prices is studied to gauge the price discovery process. Formal statistical tests are conducted based on Johansen's co‐integration, Granger causality and the Garbade‐Silber approach for the corn spot prices and futures prices. All empirical analysis is also performed for GMO and non‐GMO soybeans to provide a contrast with the corn futures market. The results suggest that Chinese corn futures prices guide the spot prices; that is, the corn futures market can serve as legitimate guide for future cash prices. This conclusion is valid for GMO futures market, but is not found to be the case for non‐GMO soybeans, where spot prices guide futures prices.
Ontogenetic changes in intralimb proportions in a Romano‐Christian period sample from the Dakhleh Oasis, Egypt
Authors: Bleuze Michele M. , Wheeler Sandra M. , Williams lana J. , Dupras Tosha L. 
Published: February 2014

ABSTRACTObjectivesThe purpose of this study is to document the appearance of adult patterns in intralimb indices during ontogeny in a skeletal sample from the Kellis 2 cemetery, Dakhleh Oasis, Egypt. In addition, this study explores evolvability in intralimb indices to understand relative differences in sensitivity to ecogeographic variables.MethodsBrachial and crural indices were compared across age cohorts with Welch's ANOVA tests andpost‐hocDunnett‐Tukey‐Kramer (DTK) pairwise multiple comparison tests. Spearman's rank correlation coefficients were used to examine developmental conservation and evolvability in intralimb proportions.ResultsBrachial and crural indices are greatest in the fetus/perinate cohort as compared to all other cohorts, decrease during infancy and early childhood, and increase during middle/late childhood. The adult pattern in the brachial index is first evident in infancy, but is not maintained throughout development. Conversely, the adult pattern in the crural index appears during early childhood and is maintained throughout development. The brachial index shows a higher degree of evolvability than the crural indexin utero.ConclusionsThe shifting pattern in intralimb proportions during development in the Kellis 2 sample is similar to that previously reported from globally diverse samples, which likely reflects the differential growth acceleration of proximal and distal intralimb skeletal elements during ontogeny. The brachial index may be more responsive to climatic conditions while the crural index may be more conserved due to functional demands. The data indicate that Kellis 2 juveniles were under strong selective pressures from climatic factors. Am. J. Hum. Biol. 26:221–228, 2014. © 2014 Wiley Periodicals, Inc.
Human body morphology, prevalence of nasopharyngeal potential bacterial pathogens, and immunocompetence handicap principal
Authors: Pawlowski Boguslaw , Nowak Judyta , Borkowska BARBARA , Drulis‐Kawa Zuzanna 
Published: February 2014

AbstractObjectiveBody height, body mass index (BMI) and waist‐to‐hip ratio (WHR) are the main traits characterizing human body morphology. Studies show that these traits are related to attractiveness and, therefore, according to an evolutionary point of view, are supposed to be honest signals of biological quality. If the immunocompetence handicap principal (IHP) is true, people with more attractive values of these traits should be more immunologically competent. To test this, we analyzed whether nasal and throat colonization with potentially pathogenic bacteria is related to body height and BMI in both sexes and to WHR in females.Methods: 103 healthy females and 90 healthy males (with the mean age of 21.4 and 22.8, respectively) participated in the study. The heights and weights were self‐reported and waist and hip circumferences measured. Six potentially pathogenic species (with the most commonStaphylococcus aureus) isolated from nasal and throat swabs were identified by colony morphology, standard biochemical assays, and latex tests. To compare carrier and noncarrier individuals, Kruskal‐Wallis test was used.ResultsColonized males had higher BMI than non‐colonized males (no difference for females) and colonized females had lower WHR's. Body height was not related to colonization in either sex.ConclusionsWe confirmed our hypothesis only for BMI in males. This result and a higher WHR in non‐colonized females indicate higher immunocompetence of those who bear the costs of higher levels of testosterone, which according to previous studies is correlated negatively to BMI in males and positively to WHR in females. Am. J. Hum. Biol. 26:305–310, 2014. © 2014 Wiley Periodicals, Inc.
A Computational Study of Allene Synthesis via the ZnI2‐Promoted Alleylation of Terminal Alkynes (ATA Reaction)
Authors: Zhang Xue 
Published: February 2014

AbstractA detailed mechanism of allene formation via the ZnI2‐promoted alleylation of terminal alkynes (ATA reaction) was investigated through DFT. The originally proposed pathway for this process was evaluated and accords perfectly with the calculated results. The formation of a propargylamine, the subsequent [1,5]‐hydride migration, and β‐elimination are the key steps of the whole process. The [1,5]‐hydride migration is the rate‐determining step. The main role of ZnI2 in the whole process is alkyne activation to facilitate the [1,5]‐hydride migration and the stabilization of the zwitterionic intermediate.
Synthesis of Substituted Quinolines by Iron(III)‐Catalyzed Three‐Component Coupling Reaction of Aldehydes, Amines, and Styrenes
Authors: Gandeepan Parthasarathy , Rajamalli P. , Cheng Chien‐Hong 
Published: February 2014

AbstractA practical and environmentally benign method for the synthesis of substituted quinolines via an FeCl3‐catalysed coupling reaction of aldehydes, amines, and styrenes in the presence of oxygen is described. The remarkable features of this quinoline synthesis include simple operation, mild reaction conditions, a wide substrate scope, a non‐toxic and inexpensive FeCl3 catalyst, readily available starting materials, the use of oxygen as an oxidant, and no hazardous byproducts.
Biocultural implications of oral pathology in an ancient Central California population
Authors: Griffin Mark C. 
Published: February 2014

ABSTRACTBioarchaeologists have long noted two unusual trends in the dentitions of prehistoric Native Californian populations: high rates of wear and low prevalence of caries. The Central California site of CA‐CCO‐548 offers a unique opportunity to examine the relationship between oral pathology and extreme dental wear in a large (n = 480), ancient (4,300–3,100 BP), and temporally well‐defined population sample. This study specifically examines three interrelated processes of the oral cavity in this population: dental wear, dental caries, and periodontal disease. The results show high levels of dental wear (average of 6.1, Smith system), low frequencies of carious lesions (2.5%), low frequencies of periodontal disease (17.8%), and high frequencies of periapical abscesses (10.7%). The pathological processes examined here have complicated multifactorial etiologies. However, they all share the common primary etiological agents of facultative pathogenic bacteria proliferation in the oral biofilm. Integration of the current etiological explanations for infections of the oral cavity, information from the ethnographic record pertaining to subsistence and activity patterns in Native Californian populations, and statistical analysis of specific disease and wear patterns leads to a novel explanation for the observed pattern of oral pathology in this population sample. Specifically, the introduction of antibacterial compounds through dietary items and non‐alimentary tooth use is suggested as the most likely explanation for the unusually low prevalence of dental caries and periodontal disease. Am J Phys Anthropol 154:171–188, 2014. © 2014 Wiley Periodicals, Inc.
Overlapping demyelinating syndromes and anti–N‐methyl‐D‐aspartate receptor encephalitis
Authors: Titulaer Maarten J. , Höftberger Romana , Iizuka Takahiro , Leypoldt Frank , McCracken Lindsey , Cellucci Tania , Benson Leslie A. , Shu Huidy , Irioka Takashi , Hirano Makito , Singh Gagandeep , Cobo Calvo Alvaro , Kaida Kenichi , Morales Pamela S. , Wirtz Paul W. , Yamamoto Tomotaka , Reindl Markus , Rosenfeld Myrna R. , Graus Francesc , Saiz Albert , Dalmau Josep 
Published: February 2014

ObjectiveTo report the clinical, radiological, and immunological association of demyelinating disorders with anti–N‐methyl‐D‐aspartate receptor (NMDAR) encephalitis.MethodsClinical and radiological analysis was done of a cohort of 691 patients with anti‐NMDAR encephalitis. Determination of antibodies to NMDAR, aquaporin‐4 (AQP4), and myelin oligodendrocyte glycoprotein (MOG) was performed using brain immunohistochemistry and cell‐based assays.ResultsTwenty‐three of 691 patients with anti‐NMDAR encephalitis had prominent magnetic resonance imaging (MRI) and/or clinical features of demyelination. Group 1 included 12 patients in whom anti‐NMDAR encephalitis was preceded or followed by independent episodes of neuromyelitis optica (NMO) spectrum disorder (5 cases, 4 anti‐AQP4 positive) or brainstem or multifocal demyelinating syndromes (7 cases, all anti‐MOG positive). Group 2 included 11 patients in whom anti‐NMDAR encephalitis occurred simultaneously with MRI and symptoms compatible with demyelination (5 AQ4 positive, 2 MOG positive). Group 3 (136 controls) included 50 randomly selected patients with typical anti‐NMDAR encephalitis, 56 with NMO, and 30 with multiple sclerosis; NMDAR antibodies were detected only in the 50 anti‐NMDAR patients, MOG antibodies in 3 of 50 anti‐NMDAR and 1 of 56 NMO patients, and AQP4 antibodies in 48 of 56 NMO and 1 of 50 anti‐NMDAR patients (p < 0.0001 for all comparisons with Groups 1 and 2). Most patients improved with immunotherapy, but compared with anti‐NMDAR encephalitis the demyelinating episodes required more intensive therapy and resulted in more residual deficits. Only 1 of 23 NMDAR patients with signs of demyelination had ovarian teratoma compared with 18 of 50 anti‐NMDAR controls (p = 0.011).InterpretationPatients with anti‐NMDAR encephalitis may develop concurrent or separate episodes of demyelinating disorders, and conversely patients with NMO or demyelinating disorders with atypical symptoms (eg, dyskinesias, psychosis) may have anti‐NMDAR encephalitis. Ann Neurol 2014;75:411–428
Phosphine‐Catalyzed Enantioselective γ‐Addition of 3‐Substituted Oxindoles to 2,3‐Butadienoates and 2‐Butynoates: Use of Prochiral Nucleophiles
Authors: Wang Tianli , Yao Weijun , Zhong Fangrui , Pang Guo Hao , Lu Yixin 
Published: February 2014

AbstractThe first phosphine‐catalyzed enantioselective γ‐addition with prochiral nucleophiles and 2,3‐butadienoates as the reaction partners has been developed. Both 3‐alkyl‐ and 3‐aryl‐substituted oxindoles could be employed in this process, which is catalyzed by a chiral phosphine that is derived from an amino acid, thus affording oxindoles that bear an all‐carbon quaternary center at the 3‐position in high yields and excellent enantioselectivity. The synthetic value of these γ‐addition products was demonstrated by the formal total synthesis of two natural products and by the preparation of biologically relevant molecules and structural scaffolds.
Das Zintl‐Klemm‐Konzept auf dem Prüfstand: eine theoretische und experimentelle Ladungsdichtestudie an der Zintl‐Phase CaSi
Authors: Kurylyshyn Iryna M. , Fässler Thomas F. , Fischer Andreas , Hauf Christoph , Eickerling Georg , Presnitz Manuel , Scherer Wolfgang 
Published: February 2014

AbstractDie Natur der chemischen Bindungen in CaSi, einem Paradebeispiel für eine Zintl‐Phase, wurde durch eine kombinierte Analyse der experimentellen und theoretischen Ladungsdichte untersucht, um das Zintl‐Klemm‐Konzept zu überprüfen. Das Vorliegen von kovalenten Si‐Si‐Wechselwirkungen, welche durch eine QTAIM‐Analyse aufgedeckt wurden, unterstützt dieses fundamentale Bindungskonzept. Durch den Einsatz einer experimentellen Ladungsdichtestudie und theoretischer Bandstrukturanalysen konnten wir jedoch klare Beweise dafür finden, dass die Kation‐Anion‐Wechselwirkung nicht als rein ionisch beschrieben werden kann, sondern auch partiell kovalenten Charakter aufweist. Zudem weichen die integrierten QTAIM‐Atomladungen der Ca‐Kationen und der Si‐Anionen mit ±1.28 e deutlich vom postulierten Idealwert von ±2 e ab, was in klarem Widerspruch zum ursprünglichen Zintl‐Klemm‐Konzept steht. Diese Beobachtungen liefern eine mögliche Erklärung für das unerwartete metallische Verhalten von CaSi.
Topochemische Pseudomorphose eines Chlorids in ein Bismutid
Authors: Kaiser Martin , Rasche Bertold , Ruck Michael 
Published: February 2014

AbstractDie heterogene Reaktion von Kristallen des erstmals synthetisierten Subhalogenids Bi12Rh3Cl2 mit einer n‐Butyllithium‐Lösung bei 70 °C führte zum vollständigen topochemischen Austausch der Chloridionen gegen Bismutatome und somit zur Transformation in den isostrukturellen, metastabilen Supraleiter Bi14Rh3. Bis auf einige Risse senkrecht zur a‐Achse blieb die Kristallmorphologie bei der Pseudomorphose unverändert. Detaillierte elektronenmikroskopische Untersuchungen der substituierten Kristalle lieferten keinen Hinweis auf Volumendefekte, die auf eine innere chemische Reaktion hindeuten würden. Demnach muss ein beträchtlicher Stofftransport durch die scheinbar dicht gepackte Kristallstruktur stattgefunden haben. Als Mechanismus für den effizienten Stofftransport wird eine zwischenzeitliche Aufweitung des dreidimensionalen Netzwerks aus kantenverknüpften [RhBi8]‐Würfeln und ‐Antiprismen angenommen. Der Ersatz der ionischen Wechselwirkung im Chlorid durch das metallische Bindungssystem der binären Verbindung schließt die Pseudolücke in der Zustandsdichte am Fermi‐Niveau. Aus einer Stabpackung leitfähiger, aber elektrisch isolierter Stränge von [RhBi8]‐Würfeln in Bi12Rh3Cl2 wird das dreidimensional metallische Bi14Rh3.