bluuebunny/crossref_metadata_2025_split huggingface dataset:
Targeted Neonatal Echocardiography Services
Authors: Finan Emer , Sehgal Arvind , Khuffash Afif El , McNamara Patrick J. 
Published: September 2014

ObjectivesTargeted neonatal echocardiography refers to a focused assessment of myocardial performance and hemodynamics directed by a specific clinical question. It has become the standard of care in many parts of the world, but practice is variable, and there has been a lack of standardized training and evaluation to date. Targeted neonatal echocardiography was first introduced to Canada in 2006. The purpose of this study was to examine the characteristics of targeted neonatal echocardiography practice and training methods in Canadian neonatal intensive care units (NICUs).MethodsA total of 142 Canadian neonatologists were invited to participate in an online survey, which was conducted in September 2010. The survey consisted of questions related to the availability of targeted neonatal echocardiography, clinical indications, benefits and risks, and training methods.ResultsThe overall survey response rate was 65%. Forty‐eight respondents (34%) indicated that targeted neonatal echocardiography was available in their units, and the program was introduced within the preceding 1 to 5 years. In centers where it was unavailable, lack of on‐site echocardiography expertise was cited as the major barrier to implementation. The most common indications for targeted neonatal echocardiography included evaluation of a hemodynamically significant ductus arteriosus, systemic or pulmonary blood flow, and response to cardiovascular treatments. Only 27% of respondents, working in centers where targeted neonatal echocardiography existed, actually performed the studies themselves; most individuals completed 11 to 20 studies per month. Almost half of the respondents said that training was available in their institutions, but methods of training and evaluation were inconsistent. Eighty‐seven percent of respondents reported no formalized process for assessment of ongoing competency after the initial training period.ConclusionsTargeted neonatal echocardiography is becoming more widely available and is gaining acceptance in Canadian NICUs. Although training is provided in many institutions, the process is not well established, and formal evaluation is rarely performed. This study emphasizes the need for development of standards for formalized training, evaluation, and quality assurance.
Resonant Tunneling Diodes
Authors: Maezawa Koichi 
Published: September 2014

AbstractRecent progress in epitaxial growth technology has made it possible to fabricate thin structures where quantum effects emerge. In these thin structures, the wave‐like nature of electrons dominates the current‐voltage characteristics. Electrons can penetrate barriers (tunneling), interfere, and make standing waves. A resonant tunneling diode (RTD) exploits such effects. RTDs are characterized by unique current‐voltage characteristics showing negative differential resistance (NDR). They consist of extremely thin semiconductor heterolayers with thicknesses of 1 to 10 nm.RTDs are attracting much attention because of their potential for high‐speed operation as well as for high functionality due to the NDR. RTDs with 1.4 THz oscillation and 1.5 ps switching have already been reported, and several functional RTD‐based circuits, which include multiple‐valued logic, a non‐linear logic gate, and a neuron‐like weighted‐sum function, have also been reported. These functions reduce the number of devices used, leading to lower power dissipation. Another advantage, one of the most important ones, is that RTDs can operate at room temperature. This differentiates RTDs from most other quantum effect devices, which can operate at only cryogenic temperatures. Thus RTDs are regarded as most practical quantum effect devices for ultra high‐speed analog and digital applications in the near future.
Sheared sheet intrusions as mechanism for lateral flank displacement on basaltic volcanoes: Applications to Réunion Island volcanoes
Authors: Cayol V. , Catry T. , Michon L. , Chaput M. , Famin V. , Bodart O. , Froger J.‐L. , Romagnoli C. 
Published: September 2014

AbstractField work carried out on the Piton des Neiges volcano (Réunion Island) suggests that the injection of magma along detachments could trigger flank failure by conjugate opening and shear displacement. We use 3‐D numerical models to compare the ability of purely opened sheet intrusions, sheared sheet intrusions, and normal faults to induce flank displacement on basaltic volcanoes. We assume that shear stress change on fractures results from stress anisotropy of the host rock under gravity. Exploring a large range of stress anisotropies, fracture dips, and fracture depth over length ratios, we determine that the amount of shear displacement is independent of the proximity to the ground surface. Sheared sheet intrusions are the most efficient slip medium on volcanoes. Consequently, the largest flank displacement is induced by the longest, deepest sheared intrusion dipping closest to 45° in a host rock with the highest stress anisotropy. Using our model in a forward way, we provide shear and normal displacements for buried fractures. Applying the model to a pile of sills at the Piton des Neiges volcano, we determine that the mean shear displacement caused by each intrusion was 3.7 m, leading to a total of a 180–260 m of lateral displacement for the 50 m high pile of sills. Using our model in an inverse way, we formulate a decision tree to determine some fracture characteristics and the host rock stress anisotropy from ratios of maximum surface displacements. This procedure provides a priori models, which can be used to bound the parameter space before it is explored through a formal inversion. Applying the decision tree to the 1.4 m coeruptive flank displacement recorded at Piton de la Fournaise in 2007, we find that it probably originated from a shallow eastward dipping subhorizontal normal fault.
Compaction creep of sands due to time‐dependent grain failure: Effects of chemical environment, applied stress, and grain size
Authors: Brzesowsky R. H. , Hangx S. J. T. , Brantut N. , Spiers C. J. 
Published: September 2014

AbstractTime‐dependent brittle creep plays a role in controlling compaction of sands and sandstones under upper crustal conditions, influencing phenomena such as production‐induced reservoir compaction, surface subsidence, and induced seismicity. Brittle creep also plays a role in determining the mechanical behavior of gouge‐rich faults. We performed uniaxial creep experiments on sand to investigate the effects of chemical environment (dry versus solution flooded), grain size (d = 196–378 µm), and applied effective stress (σa up to 30 MPa), at room temperature conditions favoring grain‐scale brittle processes. Creep measurements were complemented with acoustic emission (AE) detection and microstructural analysis to characterize the main creep mechanism. Wet samples showed much higher creep strains than dry‐tested samples. AE event counts showed a direct relation between grain failure and creep strain, with higher AE rates occurring in the wet samples. Therefore, we inferred that time‐dependent deformation was dominated by subcritical crack growth, resulting in grain failure accompanied by intergranular sliding rearrangements, and that crack growth in the presence of chemically active fluids was controlled by stress corrosion. The sensitivity of the compaction rate of the sands to d and σa can be expressed as where i ≈ 6 and j ≈ 21 under dry conditions and i ≈ 9 and j ≈ 15 under wet conditions. Our results were compared to a simple model based on Hertzian contact theory, linear elastic fracture mechanics, and subcritical crack growth. This model showed agreement between the observed stress and grain size sensitivities of creep, within a factor of 2.
Carbon dioxide fluxes of an urban tidal marsh in the Hudson‐Raritan estuary
Authors: Schäfer K. V. R. , Tripathee R. , Artigas F. , Morin T. H. , Bohrer G. 
Published: September 2014

AbstractNet ecosystem exchange (NEE) of tidal brackish wetlands in urban areas is largely unknown, albeit it is an important ecosystem service. High carbon dioxide (CO2) uptake of estuaries can potentially be achieved by creating conditions that foster CO2 uptake and sequestration. Thus, this study sought to assess NEE in a mesohaline tidal urban wetland that has been restored and determine the biophysical drivers of NEE in order to investigate uptake strength and drivers thereof. Beginning in 2009, NEE was measured using the eddy covariance technique in a restored urban estuarine wetland. Maximum NEE rates observed were −30 µmol m−2 s−1 under high light conditions in the summer. Monthly mean NEE showed this ecosystem to be a CO2 source in the winter, but a CO2 sink in summer. Conditional Granger causality showed the influence of net radiation on half daily to biweekly timescales on NEE and the influence of water level at half daily time scales. The overall productivity of this wetland is within the expected range of tidal brackish marshes and it was a sink for atmospheric CO2 in two out of the 3 years of this study and had a continued increase over the study period.
Efficiency of different heuristic approaches to calculation of electromagnetic diffraction by polyhedrons and other scatterers
Authors: Vesnik M. V. 
Published: September 2014

AbstractDifferent heuristic approaches, such as physical optics method, method of equivalent edge currents, and newly developed modified method of equivalent edge currents are exemplified in a problem of electromagnetic diffraction by a plane angular sector. Comparing with rigorous results has shown that for the problem of electromagnetic diffraction by polyhedrons physical optics method can lead to serious mistakes, method of equivalent edge currents gives a qualitatively correct solution and modified solution by equivalent edge currents method is the most close to a rigorous one. Results of this work can be extended to many scientific and engineering applications in various fields of physics and technology.
Exact versus Dupuit interface flow in anisotropic coastal aquifers
Authors: Bakker Mark 
Published: September 2014

AbstractThe Dupuit solution for interface flow toward the coast in a confined aquifer is compared to a new exact solution, which is obtained with the Hodograph method and conformal mapping. The position of the toe of the interface is a function of two dimensionless parameters: the ratio of the hydraulic gradient upstream of the interface where flow is one‐dimensional over the dimensionless density difference, and the ratio of the horizontal hydraulic conductivity over the vertical hydraulic conductivity. The Dupuit interface, which neglects resistance to vertical flow, is a very accurate approximation of the exact interface for isotropic aquifers. The difference in the position of the toe between the exact and Dupuit solutions increases when the vertical anisotropy increases. For highly anistropic aquifers, it is proposed to add an effective resistance layer along the bottom of the sea in Dupuit models. The resistance of the layer is chosen such that the head in the Dupuit model is equal to the head in the exact solution upstream of the interface where flow is one‐dimensional.
Particle Colliders
Authors: Rohlf James W. 
Published: September 2014

AbstractThe article contains sections titled:IntroductionBrief HistoryThe Birth of Particle CollidersIngredients of CollidersFamous CollidersStanford Positron Electron Accelerating RingPETRACERNProton–Antiproton ColliderFermilab Tevatron ColliderLarge Electron–Positron ProjectThe Energy Frontier:CERNLarge Hadron ColliderLHCBasic ParametersBeam DumpLHCLayoutCryogenicsInjection SchemeRadio Frequency AccelerationBeam VacuumSuperLHCThe Next FrontierInternational Linear ColliderCompact Linear ColliderVery Large Hadron Collider
Quantum Mechanics
Authors: Burgdörfer Joachim , Rotter Stefan 
Published: September 2014

AbstractQuantum mechanics (QM), also calledwave mechanics, is the modern theory of matter, of atoms, molecules, solids, and of the interaction of electromagnetic fields with matter. It supersedes the classical mechanics embodied in Newton's laws and contains them as a limiting case (the so‐called classical limit of QM). QM has proven to be an extremely successful theory, tested and confirmed to an outstanding degree of accuracy for physical systems ranging in size from subatomic partiles to macroscopic samples of matter, such as superconductors and superfluids. The present article gives a brief introduction into concepts, methods, and applications of mostly non‐relativistic quantum physics.
The Standard Model of Elementary Particles
Authors: Erler Jens 
Published: September 2014

AbstractIt is first reviewed how the concepts of a quantum field theories (QFT) and of local gauge invariance naturally arise, before they are applied to the electroweak model of leptons. This model is then extended to include quarks and the strong interaction, family replication and quark mixing, CP violation, as well as neutrino mass and mixing. Experimental tests, the determination of fundamental parameters, and constraints on and limitations of the minimal model and ideas that go beyond it are also covered.
Design and Application of Cyclotrons
Authors: Baartman Richard A. , Laxdal Robert E. , Mackenzie George H. , Rao Yi‐Nong 
Published: September 2014

AbstractThis chapter introduces fields of application for the cyclotron, some speculative, and gives illustrations of activity in some older fields of application. It describes some cyclotron technology and contains a discussion of the factors that may limit the intensity of the beam from cyclotrons.
Managing the Extreme Dataflow ofLHCExperiments
Authors: Neufeld Niko , Liko Dietrich 
Published: September 2014

AbstractThe Large Hardron Collider (LHC) will extend our knowledge of particles and their interactions to unprecedented energies. The physicists hope to obtain answers on questions ranging from the origin of mass to the nature of dark matter. The high interactions rates and the large number of detector channels result in an enormous amount of data produced in every second. New developments in the area of data acquisition have been necessary to be able to transport and filter these data with complex trigger systems. The selected data will be then recorded, resulting in datasets reaching several Petabytes. The resource requirements for the analysis of these data poses also new challenges in the offline analysis. A global computing infrastructure, the grid, has been developed to interconnect computing centers all over the world to provide these resources and to analyze the data. The article reviews these new computing challenges for LHC covering both the online and the offline aspects.
Synthesis of Allylarenes via Catalytic Decarboxylation of Allyl Benzoates
Authors: Pfister Kai F. , Grünberg Matthias F. , Gooßen Lukas J. 
Published: September 2014

AbstractA catalyst system consisting of the palladium(0) complex Pd2(dba)3 and tri(p‐tolyl)phosphine was found to efficiently promote the decarboxylation of allyl benzoates with formation of allylarenes. This catalytic CO activation followed by extrusion of carbon dioxide and CC bond formation represents a sustainable alternative to traditional waste‐intensive cross‐couplings. The scope of the transformation includes allyl and cinnamyl esters of various ortho‐substituted benzoic acids. For particularly activated substrates, the palladium catalyst can optionally be replaced by an inexpensive nickel complex.magnified image
Polymer Color Properties: Neural Network Modeling
Authors: Saeed U. , Alsadi J. , Ahmad S. , Rizvi G. , Ross D. 
Published: September 2014

AbstractThe prediction and optimization of polymer color properties is a complex problem with no easy method to predict color properties directly and accurately. The problem is especially complicated with the formulation of polymers to achieve the physical properties. By considering the formulation, the neural network has been implemented for prediction of color properties consisting of sigmoid hidden units and a linear output unit arranged in a feed forward back propagation architecture. An optimal design is accomplished for 15, 16, 17, 18, 19, and 20 hidden neurons with four different algorithms including gradient descent with momentum (GDM), resilient backpropagation (resilient backpropagation), scaled conjugate gradient (SCG), and Levenberg–Marquardt (LM) algorithm. The best result in terms of statistics is presented by the LM algorithm with 16 neurons in the designed artificial neural network (ANN) model. The degree of accuracy of the ANN model is proven acceptable in all statistical analysis and shown in results. However, it was concluded that ANN provides a possible method for the prediction of specific color tristimulus values.
Effect of Die Geometry on Drawdown Force of Polypropylene at Capillary Extrusion
Authors: SEEMORK JIRAPORN , SIRIPRUMPOONTHUM MONCHAI , LEE YOUNGJUN , NOBUKAWA SHOGO , YAMAGUCHI MASAYUKI 
Published: September 2014

ABSTRACTDrawdown force, defined as the force needed to stretch a polymer melt uniaxially at capillary extrusion, is investigated using isotactic polypropylene. In this study, we focus on the effect of die geometry on the drawdown force. As similar to the swell ratio, which decreases with increasing die length, the drawdown force is found to increase with the die length. A prolonged residence time in a long die leads to the marked orientation. Consequently, crystallization occurs rapidly after passing through a long die, which is confirmed by wide‐angle X‐ray measurements. Moreover, the rapid crystallization by the addition of a nucleating agent also enhances the drawdown force.
Self‐employed persons in Sweden ‐ mortality differentials by industrial sector and enterprise legal form: A five‐year follow‐up study
Authors: Toivanen Susanna , Mellner Christin , Vinberg Stig 
Published: September 2014

ObjectivesThis study investigated mortality differentials between self‐employed persons in Sweden, considering industrial sector, enterprise characteristics and socio‐demographic factors.MethodsData on 321,274 self‐employed persons were obtained from population registers in Sweden. Cox proportional hazards models were used to compare all‐cause and cause‐specific mortality rate ratios by industrial sector and enterprise legal form, adjusted for confounders.ResultsAll‐cause mortality was 10–32% higher in self‐employed persons in Manufacturing and Mining, Trade and Communication, and Not Specified and Other sectors than in Agriculture, Forestry, and Fishing. Mortality from cardiovascular disease was 23% higher in Trade and Communication, and from neoplasms 17–51% higher in Manufacturing and Mining, Not Specified, and Other. Mortality from suicide was 45–60% lower in Personal and Cultural Services, and in Not Specified. Mortality was 8–16% higher in sole proprietorship than limited partnership.ConclusionsFurther research of working conditions is warranted, considering industry and enterprise legal form. Am. J. Ind. Med. 58:21–32, 2015. © 2014 Wiley Periodicals, Inc.
A Cost‐Effective 3D Hydrogen Evolution Cathode with High Catalytic Activity: FeP Nanowire Array as the Active Phase
Authors: Jiang Ping , Liu Qian , Liang Yanhui , Tian Jingqi , Asiri Abdullah M. , Sun Xuping 
Published: September 2014

AbstractIron is the cheapest and one of the most abundant transition metals. Natural [FeFe]‐hydrogenases exhibit remarkably high activity in hydrogen evolution, but they suffer from high oxygen sensitivity and difficulty in scale‐up. Herein, an FeP nanowire array was developed on Ti plate (FeP NA/Ti) from its β‐FeOOH NA/Ti precursor through a low‐temperature phosphidation reaction. When applied as self‐supported 3D hydrogen evolution cathode, the FeP NA/Ti electrode shows exceptionally high catalytic activity and good durability, and it only requires overpotentials of 55 and 127 mV to afford current densities of 10 and 100 mA cm2, respectively. The excellent electrocatalytic performance is promising for applications as non‐noble‐metal HER catalyst with a high performance–price ratio in electrochemical water splitting for large‐scale hydrogen fuel production.
Conjugated‐Protein Mimics with Molecularly Imprinted Reconstructible and Transformable Regions that are Assembled Using Space‐Filling Prosthetic Groups
Authors: Takeuchi Toshifumi , Mori Takuya , Kuwahara Atsushi , Ohta Takeo , Oshita Azusa , Sunayama Hirobumi , Kitayama Yukiya , Ooya Tooru 
Published: September 2014

AbstractConjugated‐protein mimics were obtained using a new molecular imprinting strategy combined with post‐imprinting modifications. An antibiotic was employed as a model template molecule, and a polymerizable template molecule was designed, which was composed of the antibiotic and two different prosthetic groups attached through a disulfide bond and Schiff base formation. After co‐polymerization with a cross‐linker, the template molecule was removed together with the prosthetic groups, yielding the apo‐type scaffold. Through conjugation of the two different prosthetic groups at pre‐determined positions within the apo‐type scaffold, the apo cavity was transformed into a functionalized holo cavity, which enables the on/off switching of the molecular recognition ability, signal transduction activity for binding events, and photoresponsive activity.
Hoch Zinn‐selektive Stille‐Kupplung: Polymersynthese mit einem Stannol in der Hauptkette
Authors: Linshoeft Julian , Baum Evan J. , Hussain Andreas , Gates Paul J. , Näther Christian , Staubitz Anne 
Published: September 2014

AbstractDie Einbringung von Gruppe‐14‐Metallolen in halbleitende Polymere führt zu ungewöhnlichen optoelektronischen Eigenschaften. Polymere mit Stannol‐Einheiten waren bisher jedoch nicht zugänglich. Wir berichten über eine Syntheseroute zu einem wohldefinierten stannolhaltigen Polymer, dem ersten Beispiel dieser Klasse von π‐konjugierten Polymeren. Dies wurde erreicht durch die Entwicklung doppelt funktionalisierter Stannol‐Monomere und durch eine hochselektive Stille Kupplungsreaktion, welche das Zinn im Stannol unberührt lässt. Im Vergleich mit Poly(3‐n‐hexylthiophen) zeigt die Absorption des erhaltenen Polymers eine bemerkenswerte bathochrome Verschiebung.
Copper‐Catalyzed Oxidative Dimerizations of 3‐N‐Hydroxy‐aminoprop‐1‐enes to form 1,4‐Dihydroxy‐2,3‐diaminocyclohexanes with C2 Symmetry
Authors: Ghorpade Satish , Liu Rai‐Shung 
Published: September 2014

AbstractThis work describes the one‐step construction of complex and important molecular frameworks through copper‐catalyzed oxidations of cheap tertiary amines. Copper‐catalyzed aerobic oxidations of N‐hydroxyaminopropenes to form C2‐symmetric N‐ and O‐functionalized cyclohexanes are described. Such catalytic oxidations proceed with remarkable stereocontrol and high efficiency. Reductive cleavage of the two NO bonds of these products delivers 1,4‐dihydroxy‐2,3‐diaminocyclohexanes, which are important skeletons of several bioactive molecules.
Catalytic Enantioselective Synthesis of Atropisomeric Biaryls: A Cation‐Directed Nucleophilic Aromatic Substitution Reaction
Authors: Armstrong Roly J. , Smith Martin D. 
Published: September 2014

AbstractA catalytic enantioselective nucleophilic aromatic substitution reaction which yields axially chiral biaryl derivatives in excellent yields with e.r. values of up to 97:3 has been developed. This process uses a chiral counterion to direct the addition of thiophenolate to a prochiral dichloropyrimidine by a tandem desymmetrization/kinetic resolution mechanism. The products can be derivatized to a range of atropisomeric structures without any reduction in enantioenrichment, thus offering access to unexplored chiral biaryl architectures.