bluuebunny/crossref_metadata_2025_split huggingface dataset:
A global estimate of the full oceanic 13C Suess effect since the preindustrial
Authors: Eide Marie , Olsen Are , Ninnemann Ulysses S. , Eldevik Tor 
Published: February 2017

AbstractWe present the first estimate of the full global ocean 13C Suess effect since preindustrial times, based on observations. This has been derived by first using the method of Olsen and Ninnemann (2010) to calculate 13C Suess effect estimates on sections spanning the world ocean, which were next mapped on a global 1° × 1° grid. We find a strong 13C Suess effect in the upper 1000 m of all basins, with strongest decrease in the subtropical gyres of the Northern Hemisphere, where δ13C of dissolved inorganic carbon has decreased by more than 0.8‰ since the industrial revolution. At greater depths, a significant 13C Suess effect can only be detected in the northern parts of the North Atlantic Ocean. The relationship between the 13C Suess effect and the concentration of anthropogenic carbon varies strongly between water masses, reflecting the degree to which source waters are equilibrated with the atmospheric 13C Suess effect before sinking. Finally, we estimate a global ocean inventory of anthropogenic CO2 of 92 ± 46 Gt C. This provides an estimate that is almost independent of and consistent, within the uncertainties, with previous estimates.
Neogene paleoceanography of the eastern equatorial Pacific based on the radiolarian record of IODP drill sites off Costa Rica
Authors: Sandoval María I. , Boltovskoy Demetrio , Baxter Alan T. , Baumgartner Peter O. 
Published: February 2017

AbstractThe Integrated Ocean Drilling Program (IODP) Expedition 344 drilled cores following a transect across the convergent margin off Costa Rica. Two of the five sites (U1381 and U1414) are the subject of the present study. Major radiolarian faunal breaks and characteristic species groups were defined with the aid of cluster analysis, nodal analysis, and discriminant analysis of principal components. A middle‐late Miocene to Pleistocene age (radiolarian zones RN5 to RN16) was determined for the sites, which agrees with the nannofossil zonations and 40Ar/39Ar and tephra layers. Considering the northward movement of the Cocos plate (∼7.3 cm/yr), and a paleolatitude calculator, it is assumed that during the Miocene the two sites were located ∼1000 km to the southwest of their current position, slightly south of the equator. The radiolarian faunas retrieved were thus seemingly formed under the influence of different oceanic currents and sources of nutrients. Changes in the radiolarian assemblages at Site U1414 point at dissimilar environmental settings associated with the colder South Equatorial Current and the warmer Equatorial Countercurrent, as well as to coastal upwelling. These differences are best reflected by changes in the abundance of the morphotype Spongurus spp., with noticeably higher values during the Miocene, than in the Pliocene and the Pleistocene. Because Spongurus spp. is generally associated with cooler waters, these abundance variations (as well as those of several other species) suggest that during the Miocene the area had a stronger influence of colder waters than during younger periods. During the Pliocene and the lowermost Pleistocene, biogenic remains are scarce, presumably due to the terrigenous input, which could have diluted and affected the preservation of pelagic fossils, as well as to the displacement of the site to warmer waters. A typically tropical fauna characterized the Pleistocene, yet with widespread presence of colder water species, most probably indicative of the influence of coastal upwelling processes.
Seasonal and interannual variability of the Eastern Tropical Pacific Fresh Pool
Authors: Guimbard S. , Reul N. , Chapron B. , Umbert M. , Maes C. 
Published: February 2017

AbstractThe Eastern Pacific Fresh Pool (EPFP) is a large region of low sea surface salinity (SSS) defined by values lower than 34 practical salinity scale within (5°S–30°N, 75°W–180°W). The fresh pool dynamically responds to strong regional and seasonally varying ocean‐atmosphere‐land interactions (including monsoon rain, trade and gap winds, and strong currents). Using more than 5 years of Soil Moisture and Ocean Salinity (SMOS) satellite sea surface salinity (SSS) and complementary satellite wind, rain, currents, and sea surface temperature data together with a historical ensemble of in situ products, the present study explores the seasonal and interannual dynamics of the fresh pool over the period 2004–2015. An important interannual variability of the maximal surface extension of the EPFP over the past decade is revealed with two extreme events (2012, 2015) occurring during the SMOS satellite period. These extremes are found to be related to the El Niño‐Southern Oscillation (ENSO) phases and associated anomalies of precipitation, surface currents, and trade wind in the central Pacific. In 2012 (La Niña), stronger trade winds coupled with a deficit of precipitation induced a minimum extension of the pool during the rainy season. Whereas, during the strong El Niño 2014–2015, the EPFP extension reached an unprecedented maximum value. A modification of the atmospheric freshwater fluxes and ocean surface currents during winter 2014 is found to have favored the onset of this abnormal fresh event.
The study of droplet‐laden turbulent airflow over waved water surface by direct numerical simulation
Authors: Druzhinin O. A. , Troitskaya Yu. I. , Zilitinkevich S. S. 
Published: February 2017

AbstractThe objective of the present paper is to elucidate possible effects of sea spray on the momentum transfer in marine boundary layer under strong wind forcing conditions by performing direct numerical simulation (DNS) of turbulent, droplet‐laden airflow over a waved water surface. Three‐dimensional, turbulent Couette airflow is considered in DNS as a model of a constant‐flux layer in the atmospheric surface layer. Two‐dimensional stationary waves at the water surface are prescribed and assumed to be unaffected by the airflow and/or droplets. Droplets are considered as nondeformable spheres and tracked in a Lagrangian framework, and their impact on the carrier flow is modeled with the use of a point‐force approximation. The results show that drops dynamics and their impact on the carrier airflow is controlled by the drops velocity at injection, the ratio of drops gravitational settling velocity versus the product of air friction velocity and Karman constant (
), and the wave slope, ka. Drops injected into the flow with the surrounding airflow velocity reduce the turbulent air‐stress and increase mean air velocity as compared to the droplet‐free case. On the other hand, the opposite effect is observed for drops injected with velocity equal to the water surface velocity, which increase the turbulent air stress and reduce the mean wind velocity. This modification of the airflow by drops is most pronounced for the ratio
, increases with drops mass loading, and is reduced for steeper waves and smaller settling velocity.
On the response of the Lorenz energy cycle for the Southern Ocean to intensified westerlies
Authors: Wu Yang , Wang Zhaomin , Liu Chengyan 
Published: February 2017

AbstractThe potential impact of intensified westerlies on the Lorenz energy cycle for the Southern Ocean is examined by employing a global eddy‐permitting ocean‐sea ice model. Two idealized sensitivity experiments are designed for this purpose: one is driven by 1992 forcing with weaker westerlies and the other driven by 1998 forcing with stronger westerlies. The intensified westerlies lead to the most significant increase of about 30% in the eddy kinetic energy (EKE) reservoir, followed by the mean kinetic energy (MKE) reservoir increase (17.9%), eddy available potential energy (EAPE) reservoir increase (8.6%), and mean available potential energy (MAPE) reservoir increase (6.5%). In contrast, the increases in the generations of kinetic energy and available potential energy are quite similar, ranging from 21% for EAPE generation to 26% for MKE generation. There are considerably increased energy transfers from MKE to MAPE (about 75%) and from MAPE to EAPE (about 78%), reflecting greatly enhanced baroclinic instability pathway. The conversion rates are strongly influenced by large topography; in particular, a relatively large energy conversion from EKE to MKE exists in the regions associated with large topography, in contrast to the energy flow from MKE to EKE over the broad Southern Ocean. Under stronger wind forcing, all energy conversions are enhanced, and the increases in the conversion rates from EAPE to EKE and from EKE to MKE are more prominent than the increases from MKE to MAPE and from MAPE to EAPE near large topography.
Reconstructing diet in Napoleon's Grand Army using stable carbon and nitrogen isotope analysis
Authors: Holder Sammantha , Dupras Tosha L. , Jankauskas Rimantas , Williams Lana , Schultz John 
Published: February 2017

AbstractObjectivesHistorical evidence has provided information regarding disease and mortality in Napoleon Bonaparte's Grand Army, but dietary information beyond individual soldier accounts remains scarce. The purpose of this research is to reconstruct the diets of Napoleon's multiethnic army who were associated with the Russian Campaign of 1812.Materials and MethodsWe conducted stable carbon and nitrogen isotope ratio analysis on femoral bone collagen of 78 individuals recovered from a salvage excavation at the mass gravesite of Šiaurės miestelis in Vilnius, Lithuania. These individuals were later discovered to be Napoleonic soldiers and camp followers who participated in the 1812 Russian Campaign.ResultsStable carbon isotope ratios range from −19.2‰ to −11.8‰, with a mean of −17.8‰ ± 1.5‰ (1 σ). Stable nitrogen isotope ratios range from 7.1‰ to 13.6‰, with a mean of 10.5‰ ± 1.4‰ (1 σ). Both δ13C and δ15N values show a wide range of variation.DiscussionStable isotope data indicate considerable dietary variation in this population associated with a multiethnic and socially stratified military population. Diets ranged from predominantly C3‐based to predominantly C4‐based, with varying inputs of terrestrial, freshwater, and marine animal protein. Comparison with other European populations further denotes the exceptional range of dietary variation of soldiers and camp followers in Napoleon's army.
Blood–brain barrier breakdown in reversible cerebral vasoconstriction syndrome: Implications for pathophysiology and diagnosis
Authors: Lee Mi Ji , Cha Jihoon , Choi Hyun Ah , Woo Sook‐Young , Kim Seonwoo , Wang Shuu‐Jiun , Chung Chin‐Sang 
Published: February 2017

ObjectiveDiagnosis of reversible cerebral vasoconstriction syndrome (RCVS) is currently based on luminographic findings of vasoconstriction. In addition to vasoconstriction, the blood–brain barrier (BBB) breakdown has been postulated as a central mechanism of RCVS. Our aim was to document BBB breakdown in patients with RCVS and its role for the pathophysiology‐based diagnosis of RCVS.MethodsWe prospectively recruited 72 consecutive patients with thunderclap headache who did not have aneurysmal subarachnoid hemorrhage from April 2015 to July 2016 at the Samsung Medical Center. Based on the International Classification of Headache Disorders–3 beta criteria and neuroimaging, patients were classified as having RCVS (n = 41; “definite” in 29 imaging‐proven patients and “probable” in 12 imaging‐negative patients), other secondary causes (n = 7), and thunderclap headache of undetermined cause (n = 24). BBB breakdown was evaluated using contrast‐enhanced fluid‐attenuated inversion recovery magnetic resonance imaging.ResultsBBB breakdown was documented in 20 (69.0%) patients with definite RCVS, 3 (25.0%) patients with probable RCVS, and none with other secondary causes. BBB breakdown was present in RCVS patients with (n = 4) and without (n = 19) concomitant posterior reversible encephalopathy syndrome. In patients with RCVS, the extent of BBB breakdown was independently associated with neurological complications (multivariate odds ratio = 1.48 per 1 territorial increase, 95% confidence interval = 1.04–2.12, adjusted p = 0.032). Three (12.5%) patients with thunderclap headache of undetermined cause were newly classified as having RCVS by the presence of BBB breakdown.InterpretationThis is the first study to show BBB breakdown in patients with RCVS. This finding might broaden our understanding of the pathophysiology and clinical spectrum of RCVS. Ann Neurol 2017;81:454–466
Solid‐state NMR and EPR Spectroscopy of Mn2+‐Substituted ATP‐Fueled Protein Engines
Authors: Wiegand Thomas , Lacabanne Denis , Keller Katharina , Cadalbert Riccardo , Lecoq Lauriane , Yulikov Maxim , Terradot Laurent , Jeschke Gunnar , Meier Beat H. , Böckmann Anja 
Published: February 2017

AbstractParamagnetic metal ions deliver structural information both in EPR and solid‐state NMR experiments, offering a profitable synergetic approach to study bio‐macromolecules. We demonstrate the spectral consequences of Mg2+/ Mn2+ substitution and the resulting information contents for two different ATP:Mg2+‐fueled protein engines, a DnaB helicase from Helicobacter pylori active in the bacterial replisome, and the ABC transporter BmrA, a bacterial efflux pump. We show that, while EPR spectra report on metal binding and provide information on the geometry of the metal centers in the proteins, paramagnetic relaxation enhancements identified in the NMR spectra can be used to localize residues at the binding site. Protein engines are ubiquitous and the methods described herein should be applicable in a broad context.
Dielectric relaxations in phosphoric acid‐doped poly(2,5‐benzimidazole) and its composite membranes
Authors: Saleha Wasim F. G. , Ramesh Rahul , Nalajala Naresh , Ladewig Bradley P. , Neergat Manoj 
Published: February 2017

ABSTRACTPoly(2,5‐benzimidazole) (ABPBI)—a promising high‐temperature polymer electrolyte membrane—is characterized over a wide range of temperature (−50 to 220 °C) using broadband dielectric spectroscopy (BDS) to understand the various relaxation processes. The undoped ABPBI membrane shows two major secondary relaxations and a primary α relaxation. The effect of phosphoric acid (PA) and phosphotungstic acid grafted zirconium dioxide (PWA/ZrO2) nanoparticles on the chain relaxation and the proton conductivity is investigated. The phosphoric acid alters the relaxation trends, increases the number of free ions in the polymer matrix, and therefore the conductivity. The shift in the peak frequencies of different chain relaxation processes in the presence of PA and PWA/ZrO2 is attributed to the increase in free volume and the consequent easy motion of the polymer chains. The Fourier transform infra‐red (FTIR) spectroscopy of ABPBI and the acid‐doped composites show all the relevant peaks corresponding to CC, CN stretching, and phosphoric acid/phosphates, confirming the formation of ABPBI and doping with PA. The proton conductivity of the membranes is estimated from electrochemical impedance spectroscopy (EIS). To establish the effect of change in crystallinity on relaxations and proton conductivity, the undoped and PA‐doped membranes are characterized using thermogravimetric analysis and in situ XRD at high temperatures. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44867.
A reassessment of cervical surface anatomy via CT scan in an adult population
Authors: Shen Xin‐Hua , Xue Hua‐Dan , Chen Yu , Wang Man , Mirjalili S. Ali , Zhang Zhu‐Hua , Ma Chao 
Published: February 2017

Surface landmarks in the neck are important for orientations of cervical glands, arteries, veins, nerves, and vertebrae. Recent research suggests some orientations are not correct. What are the cervical landmark orientations in the Chinese population? In this study, two essential cervical anatomy planes, the thyroid cartilage and C7 planes, were assessed in living adult Chinese subjects using computed tomography (CT), and the hyoid, carotid bifurcation, cricoid cartilage, thyroid arteries, and vertebral artery were simultaneously positioned. After excluding patients with distorting pathology, a total of 108 cervical CT scans were examined. The thyroid cartilage plane commonly passed through the C5 (in males) or C4 (in females) vertebral level. The carotid artery bifurcated most commonly at C3 (left) or C4 (right), more than 10 mm above the thyroid cartilage plane bilaterally in most cases. Orientation of the carotid bifurcation according to the body or greater horn of the hyoid was more accurate. The superior thyroid artery was found a finger‐breadth below the thyroid cartilage plane, and the inferior thyroid artery in the C7 plane. The inferior border of the cricoid cartilage was most often at C7 (in males) or C6 (in females). The vertebral artery entered the C6 transverse foramen in more than 80% of scans. This reassessment of cervical surface anatomy using modern imaging tools in vivo provides both qualitative and quantitative information for surgeons in clinical practice. Clin. Anat. 30:330–335, 2017. © 2017 Wiley Periodicals, Inc.
Implementation of competency‐based curriculum: College of Philosophy, Universidad Nacional del Este, Paraguay
Authors: de las Nieves Pereira de Vallejos A. , Giménez Morel R.A. , Tusing J. 
Published: February 2017

BackgroundOur current knowledge‐based society demands that new information be quickly incorporated into daily practices, thus leading to a better and more equitable society. For universities, this involves preparing students by linking the skills developed through a major's curriculum directly to their application in the labor market. From 2011 to 2013, the College of Philosophy of the Universidad Nacional del Este, Paraguay instituted a competency‐based curriculum model in the first 3 years of study for Education Science, Communication Science, Psychology, Mathematics, Letters, Philosophy and History majors.AimsThe research team sought to evaluate faculty and student perceptions of the faculty's preparedness and ability to administer this new curriculum. Additionally, the impact on student learning and skill development was also assessed.MethodsBoth students and faculty completed a two‐part survey evaluating these topics and ten key respondents completed an additional in‐depth interview to provide a qualitative dimension to the research.ResultsThe research demonstrated that the new curriculum is open, participatory, contextualized, process‐oriented, dynamic, interdisciplinary and adaptable to changes and advances in the pedagogical disciplines as well as in society at large.ConclusionsThis new approach demands a lot of commitment from all participants as feedback is used to revise the teaching–learning process and to reevaluate which skills and competencies are in highest demand in both local and global labor markets.
Manual thrombectomy efficiency in relationship to the area at risk in patients with myocardial infarction with TIMI 0‐1 coronary flow: Insights from an all comers registry
Authors: Luz André , Silveira Inês , Brochado Bruno , Rodrigues Patrícia , João Sousa Maria , Santos Raquel , Trêpa Maria , Santos Mário , Silveira João , Torres Severo , Leite‐Moreira Adelino F. , Carvalho Henrique 
Published: February 2017

ObjectivesTo review the effectiveness of manual thrombectomy (MT) in a series of patients with ST‐elevation myocardial infarction (STEMI) exclusively presenting with TIMI 0‐1 flow undergoing percutaneous coronary intervention (PCI), in accordance to the angiographically estimated area at risk (AAR). Second, to assess major in‐hospital clinical events, emphasizing neurological outcomes.BackgroundThe routine utilization of MT in STEMI is not recommended. However, in recent trials, a significant proportion of patients had neither large thrombus burden nor a totally occluded coronary segment, neutralizing the expected benefits of MT. In addition, the efficiency of MT to remove thrombus has rarely been addressed. Finally, MT diminished distal embolization, which has been related to mortality.ResultsIn 850 consecutive STEMI‐patients, MT was utilized in 525 (62%) and it was considered efficient (TIMI 2‐3 flow after MT) in 445 (85%). We found a significant interaction between the AAR and the effectiveness of MT to reduce infarct size (P‐interaction = 0.014). In patients having AAR ≥ 28% (n = 184), efficient MT conferred lesser infarct size compared to inefficient MT (Ln‐transformed peak CK): 7.87 ± 0.86 versus 8.36 ± 0.41 IU/L, P = 0.005, with no impact for AAR <28%. Clinical outcomes including stroke between MT and PCI‐only groups were not different.ConclusionIn comparison with the group where MT was inefficient, efficient MT may modestly reduce final infarct size without a significant clinical benefit. In comparison with PCI‐only, no difference was found regarding stroke. © 2017 Wiley Periodicals, Inc.
Enhancing Photocatalytic Hydrogen Generation: the Impact of the Peripheral Ligands in Ru/Pd and Ru/Pt Complexes
Authors: Das Nivedita , Bindra Gurmeet Singh , Paul Avishek , Vos Johannes G. , Schulz Martin , Pryce Mary T. 
Published: February 2017

AbstractThe synthesis, photophysical properties and photocatalytic efficiency of a range of novel supramolecular assemblies of the type [Ru(dceb)2(μ‐bisbpy)MCl2][PF6]2 and [Ru(bpy)2(μ‐bisbpy)MCl2][PF6]2 (M=Pd or Pt, dceb=diethyl 2,2’‐bipyridine‐4,4’‐dicarboxylate, bpy=2,2’‐bipyridine and bisbpy=2,2’:5’,3’’:6’’,2’’’‐quaterpyridine) are reported. Photocatalytic hydrogen generation was dependent on the nature of the peripheral ligand, on the catalytic centre and on the amount of water present in the photocatalytic mixture. The best catalytic conditions were obtained with the dceb peripheral ligand (turnover numbers up to 513 after 18 h). The experimental data and DFT calculations on both the bpy‐ and dceb‐based compounds indicated that the peripheral dceb ligands participated in the photocatalytic process.
Synthesis of 2‐Aminofurans by Sequential [2+2] Cycloaddition–Nucleophilic Addition of 2‐Propyn‐1‐ols with Tetracyanoethylene and Amine‐Induced Transformation into 6‐Aminopentafulvenes
Authors: Shoji Taku , Nagai Daichi , Tanaka Miwa , Araki Takanori , Ohta Akira , Sekiguchi Ryuta , Ito Shunji , Mori Shigeki , Okujima Tetsuo 
Published: February 2017

AbstractSynthesis of 2‐aminofuran derivatives with an azulene or N,N‐dimethylanilino substituent was established by the formal [2+2] cycloaddition–retroelectrocyclization of 3‐(1‐azulenyl or N,N‐dimethylanilino)‐2‐propyn‐1‐ols with tetracyanoethylene, followed by intramolecular nucleophilic addition to the initially formed tetracyanobutadiene moiety of the internal hydroxyl group that come from 2‐propyn‐1‐ol. The reaction proceeds under mild conditions with short reaction period. The products of the reaction are readily available through a simple purification procedure. 2‐Aminofuran derivatives obtained by this reaction could be converted into 6‐aminofulvene derivatives upon reaction with various amines. The structures of 2‐aminofuran and 6‐aminopentafulvene with a N,N‐dimethylanilino substituent were confirmed by single‐crystal X‐ray structural analysis.
Intermediates Stabilized by Tris(triazolylmethyl)amines in the CuAAC Reaction
Authors: Chen Haoqing , Cai Chengzhi , Li Siheng , Ma Yong , Luozhong Sijin , Zhu Zhiling 
Published: February 2017

AbstractTris(triazolylmethyl)amine ligands (TL) are widely used to accelerate the CuI‐catalyzed azide‐alkyne cycloaddition (CuAAC) reaction, but its mechanistic role remains unclear. Using electrospray ionization mass spectrometry, we detected for the first time the trinuclear TL‐CuI3‐acetylide and the dinuclear TL‐CuI2‐acetylide complexes in aqueous solution. The apparent second‐order rate constants of their reaction with an azide were 27 and 783 m−1⋅s−1 when the alkyne was tethered to TL. In the catalytic system without the tether, the rate constant increased to >146 m−1⋅s−1 for the TL‐CuI3‐acetylide, but dropped about 14‐fold to approximately 55 m−1⋅s−1 for the TL‐CuI2‐acetylide. The results indicated that TL accelerated the reaction by stabilizing the CuI2‐ and CuI3‐acetylide and their azide‐adduct intermediates, but this role is largely weakened by excess alkyne and other competing ligands under catalytic conditions.