bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling 2 m air temperatures over mountain glaciers: Exploring the influence of katabatic cooling and external warming
Authors: Ayala A. , Pellicciotti F. , Shea J. M. 
Published: March 2015

AbstractAir temperature is one of the most relevant input variables for snow and ice melt calculations. However, local meteorological conditions, complex topography, and logistical concerns in glacierized regions make the measuring and modeling of air temperature a difficult task. In this study, we investigate the spatial distribution of 2 m air temperature over mountain glaciers and propose a modification to an existing model to improve its representation. Spatially distributed meteorological data from Haut Glacier d'Arolla (Switzerland), Place (Canada), and Juncal Norte (Chile) Glaciers are used to examine approximate flow line temperatures during their respective ablation seasons. During warm conditions (off‐glacier temperatures well above 0°C), observed air temperatures in the upper reaches of Place Glacier and Haut Glacier d'Arolla decrease down glacier along the approximate flow line. At Juncal Norte and Haut Glacier d'Arolla, an increase in air temperature is observed over the glacier tongue. While the temperature behavior over the upper part can be explained by the cooling effect of the glacier surface, the temperature increase over the glacier tongue may be caused by several processes induced by the surrounding warm atmosphere. In order to capture the latter effect, we add an additional term to the Greuell and Böhm (GB) thermodynamic glacier wind model. For high off‐glacier temperatures, the modified GB model reduces root‐mean‐square error up to 32% and provides a new approach for distributing air temperature over mountain glaciers as a function of off‐glacier temperatures and approximate glacier flow lines.
Z‐Selektive Kreuzmetathese mit Ruthenium‐Katalysatoren: Anwendung in der Synthese und mechanistische Aspekte
Authors: Herbert Myles B. , Grubbs Robert H. 
Published: March 2015

AbstractDie Olefin‐Kreuzmetathese ist eine besonders nützliche Reaktion, die intensiv in der Synthese von komplexen Verbindungen genutzt wurde. Bis vor kurzem war es jedoch nicht möglich, Z‐Olefine mit dieser Methode herzustellen. Mit der Entdeckung und Entwicklung dreier Klassen von Ruthenium‐Katalysatoren wurde die Synthese von Z‐Olefinen mittels Kreuzmetathese nun ermöglicht und wird zunehmend populärer. Insbesondere Ruthenium‐Komplexe mit cyclometallierten NHC‐Liganden, die in unserem Labor entwickelt wurden, konnten erfolgreich in verschiedenen Kreuzmetathesen eingesetzt werden. Sie zeichnen sich durch eine hohe Aktivität und nahezu vollständige Z‐Selektivität aus. Dieser Kurzaufsatz gibt einen Überblick über die bisher untersuchten Kreuzmetathesereaktionen.
Sensitivity of PBL parameterization schemes of Weather Research Forecasting Model and coupling with AERMOD in the dispersion of NOX over Visakhapatnam (India)
Authors: Boadh Rahul , Satyanarayana A. N. V. , Rama Krishna T. V. B. P. S. , Madala Srikanth 
Published: March 2015

AbstractAn attempt has been made to develop a pre‐processor coupler for offline coupling of atmospheric mesoscale model (WRF) with a dispersion model (AERMOD) to estimate the ground level concentrations due to industrial sources over a coastal city, Visakhapatnam, India. To integrate AERMOD in standalone mode, surface and upper meteorological observations and various planetary boundary layer (PBL) parameters with good temporal resolution are required, that are absent for most locations in India. We have developed an integrated WRF‐AERMOD modeling system that gets required PBL parameters the pre‐processor coupler. Using this model, evaluation of the dispersion of nitrogen oxides (NOX) over Visakhapatnam during summer month with emission inventory of elevated point sources of various industries is conducted. Sensitivity studies of PBL schemes of WRF after validation reveal that the non‐local schemes, Yonsei University (YSU) followed by Asymmetric Convective Model version 2 (ACM2), captured well the characteristic variations of surface meteorological variables, vertical atmospheric structure. After validating with monitored air quality data, it is found that the integrated model with YSU followed by ACM2 is good in simulating ground level concentrations of NOX. The present work advocates that the developed modeling system is useful for better assessment of pollution dispersion over coastal regions. © 2015 Curtin University of Technology and John Wiley & Sons, Ltd.
Partially‐observable stochastic hybrid systems (poshss) state estimation and optimal control
Authors: Liu Weiyi , Hwang Inseok 
Published: March 2015

AbstractThis paper discusses the state estimation and optimal control problem of a class of partially‐observable stochastic hybrid systems (POSHS). The POSHS has interacting continuous and discrete dynamics with uncertainties. The continuous dynamics are given by a Markov‐jump linear system and the discrete dynamics are defined by a Markov chain whose transition probabilities are dependent on the continuous state via guard conditions. The only information available to the controller are noisy measurements of the continuous state. To solve the optimal control problem, a separable control scheme is applied: the controller estimates the continuous and discrete states of the POSHS using noisy measurements and computes the optimal control input from the state estimates. Since computing both optimal state estimates and optimal control inputs are intractable, this paper proposes computationally efficient algorithms to solve this problem numerically. The proposed hybrid estimation algorithm is able to handle state‐dependent Markov transitions and compute Gaussian‐ mixture distributions as the state estimates. With the computed state estimates, a reinforcement learning algorithm defined on a function space is proposed. This approach is based on Monte Carlo sampling and integration on a function space containing all the probability distributions of the hybrid state estimates. Finally, the proposed algorithm is tested via numerical simulations.
Automatic Control of Aircraft in Lateral‐Directional Plane During Landing
Authors: Lungu Romulus , Lungu Mihai 
Published: March 2015

AbstractThe paper focuses on the automatic control of aircraft in the lateral‐directional plane during the landing approach phase, taking into account crosswind and sensor errors. Two new automatic landing systems are designed using the H‐inf control, dynamic inversion, optimal observers, and reference models. To validate them, we use the dynamics associated with the landing of a light airplane, we software implement the theoretical results, and analyze the accuracy of the results and the precision standards’ achievement with respect to the requirements of the Federal Aviation Administration for lateral error during the lateral‐directional motion of the aircraft during the landing approach phase.
Kinetic Study of Catalytic Steam Gasification of Biomass by Using Reactive Flash Volatilisation
Authors: Chan Fan Liang , Umeki Kentaro , Tanksale Akshat 
Published: March 2015

AbstractReactive flash volatilisation is an autothermal process to convert biomass into tar‐free synthesis gas under steam‐rich conditions. This article studies the kinetics of reactive flash volatilisation by using Ni, PtNi, RuNi, ReNi, and RhNi catalysts supported on alumina. The rates of mass loss of cellulose, xylan, and lignin were measured and compared with those of the synthetic biomass mixture and pinewood sawdust. The kinetic parameters were calculated with and without catalysts by using a wire‐mesh isothermal thermogravimetric analyser in an equimolar steam/N2 atmosphere and high heating rates of 8.6×102, 1.1×103, and 1.3×104 °C min−1 at 700, 750, and 800 °C, respectively. The results revealed three distinct regimes of the rate of mass loss: pyrolytic decomposition, reforming, and char gasification. The catalysts increased the rate of mass loss in the reforming regime. RhNi and RuNi supported catalysts showed higher reforming rates than other catalysts. This study provides direct evidence of the in situ catalytic removal of tar during gasification of biomass.
Impact of Metabolic Syndrome on Development of Contrast‐Induced Nephropathy After Elective Percutaneous Coronary Intervention Among Nondiabetic Patients
Authors: Ozcan Ozgur Ulas , Adanir Er Hacer , Gulec Sadi , Ustun Elif Ezgi , Gerede Demet Menekse , Goksuluk Huseyin , Tulunay Kaya Cansin , Erol Cetin 
Published: March 2015

ABSTRACTBackgroundIdentifying patients who are vulnerable to development of contrast‐induced nephropathy (CIN) is essential because of its association with prolonged hospitalization, increased cost, and increased in‐hospital and long‐term mortality rates.HypothesisIndividual components of metabolic syndrome (MetS) are well‐established risk factors for kidney injury. Nondiabetic patients diagnosed with MetS might be at an increased risk of developing CIN after elective percutaneous coronary intervention (PCI).MethodsA total of 599 nondiabetic patients were enrolled, of whom 313 met the MetS criteria and 286 were included in the control group. Patients were evaluated for development of CIN after elective PCI.ResultsContrast‐induced nephropathy occurred in 9.3% (29 of 313) of the MetS group and 4.9% (14 of 286) of the control group (P = 0.04). The multivariable regression model revealed that baseline glomerular filtration rate < 30 mL/min, multivessel intervention, and MetS increased and use of statin decreased the probability of CIN independent from confounding factors (odds ratio [OR]: 7.84, 95% confidence interval [CI]: 3.46‐24.36, P < 0.01 for baseline glomerular filtration rate < 30 mL/min; OR: 0.82, 95% CI: 0.42‐0.96, P = 0.02 for statin use; OR: 2.64, 95% CI: 1.46‐6.56, P < 0.01 for multivessel intervention; and OR: 1.66, 95% CI: 1.12‐2.61, P = 0.03 for MetS).ConclusionsMetabolic syndrome is a risk factor for CIN in patients with stable coronary artery disease who undergo elective PCI. We suggest that clinicians recognize the patients with MetS before elective coronary interventions.
The effective phase of soft RF pulses
Authors: Hennel Franciszek 
Published: March 2015

ABSTRACTIn this article, the seemingly trivial relation between the spin nutation phase and the phase of radiofrequency (RF) pulses used in NMR is discussed, which in the case of soft (selective) pulses appears more subtle. Unlike hard pulses applied at a common carrier frequency, soft pulses usually have different frequency offsets in the same sequence and their nutation phase cannot be directly linked with the RF phase shift, as the phase shift has no absolute meaning for waves of different frequency. The problem is further complicated in MRI, where RF pulses are accompanied by a time‐dependent slice selection field gradient leading to surprising effects, for example, when two consecutive pulses of identical frequency and phase rotate the spins around different axes depending on slice position. A rule is described that lets the effective nutation phase be derived from the time course the RF phase. Ways to control this time course using various options of digital synthesis are presented. The discussion is illustrated by two popular MRI sequences—fast spin echo (RARE) and balanced steady‐state free precession (true FISP)—whose phase sensitivity easily leads to a pitfall when the frequency synthesis is not programmed with sufficient care. © 2015 Wiley Periodicals, Inc. Concepts Magn Reson Part A 43A: 127–137, 2015.
A single phantom to mimic 1H MR spectra of different tissues
Authors: Boizán Alejandro Bordelois , Gambarota Giulio , Noury Fanny , Saint‐Jalmes Hervé 
Published: March 2015

ObjectTo design and build a single phantom, encompassing various elementary tubes, that mimics the 1H magnetic resonance (MR) spectra of liver, prostate, muscle and brain.Materials and MethodsHigh‐resolution NMR tubes were filled with water and the metabolite of interest, at a concentration of 50 mM, or with dairy cream or oil. The tubes (5 mm outer diameter) were placed into a plastic support, the ensemble was positioned in the center of a cuboid container filled with water. Simulations of the magnetic field inhomogeneity arising from the susceptibility variations in the current phantom were also performed. MR localized spectroscopy was performed on a 1.5 T clinical scanner.ResultsMR spectra of voxels positioned in four different locations of the phantom closely mimicked the resonance peaks of liver, prostate, muscle and brain in vivo MR spectra. In particular, for the muscle spectrum, the intramyocellular lipid (IMCL) and extramyocellular lipid (EMCL) resonances were obtained using dairy cream and oil, respectively. Simulations of the magnetic field inhomogeneity in the phantom showed that in the case of an NMR tube length five times greater than the thickness of the volume of interest, it is not necessary to fill the container with water. However, to ensure a good reception level and shim settings, the NMR tubes were immersed in water.ConclusionsA single phantom of new design, that is easily built and highly reconfigurable, is here presented, to mimic the in vivo MR spectra of liver, prostate, muscle, brain and other models as needed. © 2015 Wiley Periodicals, Inc. Concepts Magn Reson Part A 43A: 138–145, 2015.
A comprehensive discussion of HMBC pulse sequences. III. Solving the problem of missing and weakly observed long‐range correlations
Authors: Furrer Julien 
Published: March 2015

ABSTRACTThe intensity of long‐range correlations observed with the classical HMBC pulse sequence using static optimization of the long‐range coupling delay is directly related to the size of the coupling constant and is often set as a compromise. As such, some long‐range correlations might appear with a reduced intensity or might even be completely absent from the spectra. After a short introduction, this third manuscript will give a detailed review of some selected HMBC variants dedicated to improve the detection of long‐range correlations, such as the ACCORD‐HMBC, CIGAR‐HMBC, and Broadband HMBC experiments. Practical details about the accordion optimization, which affords a substantial improvement in both the number and intensity of the long‐range correlations observed, but introduces a modulation in F1, will be discussed. The incorporation of the so‐called constant time variable delay in the CIGAR‐HMBC experiment, which can trigger or even completely suppress 1H–1H coupling modulation inherent to the utilization of the accordion principle, will be also discussed. The broadband HMBC scheme, which consists of recording a series of HMBC spectra with different delays set as a function of the long‐range heteronuclear coupling constant ranges and transverse relaxation times T2, is also examined. © 2015 Wiley Periodicals, Inc. Concepts Magn Reson Part A 43A: 177–206, 2015.
Twenty‐four‐hour heart rate lowering with ivabradine in chronic heart failure: insights from the SHIFT Holter substudy
Authors: Böhm Michael , Borer Jeffrey S. , Camm John , Ford Ian , Lloyd Suzanne M. , Komajda Michel , Tavazzi Luigi , Talajic Mario , Lainscak Mitja , Reil Jan‐Christian , Ukena Christian , Swedberg Karl 
Published: March 2015

AbstractAimsAnalysis of 24‐h Holter recordings was a pre‐specified substudy of SHIFT (Systolic Heart Failure Treatment with the If Inhibitor Ivabradine Trial) for exploring the heart rhythm safety of ivabradine and to determine effects of ivabradine on 24‐h, daytime, and night‐time heart rate (HR) compared with resting office HR.Methods and resultsThe 24‐h Holter monitoring was performed at baseline and 8 months after randomization to ivabradine (n = 298) or matching placebo (n = 304) titrated maximally to 7.5 mg b.i.d. in patients with baseline HR ≥70 b.p.m. Patients received guideline‐based optimized heart failure therapy including ACE inhibitors and/or ARBs in 93% and beta‐blockers at maximally tolerated doses in 93%. After 8 months, HR over 24 h decreased by 9.5 ± 10.0 b.p.m. with ivabradine, from 75.4 ± 10.3 b.p.m. (P < 0.0001), and by 1.2 ± 8.9 b.p.m. with placebo, from 74.8 ± 9.7 b.p.m. (P < 0.0001 for difference vs. ivabradine). HR reduction with ivabradine was similar in resting office and in 24‐h, awake, and asleep recordings, with beneficial effects on HR variability and no meaningful increases in supraventricular or ventricular arrhythmias. At 8 months, 21.3% on ivabradine vs. 8.5% on placebo had ≥1 episode of HR <40 b.p.m. (P < 0.0001). No episode of HR <30 b.p.m. was recorded; 3 (1.2%) patients had RR intervals >2.5 s on ivabradine vs. 4 (1.6%) patients on placebo. No RR intervals >3 s were identified in patients taking ivabradine.ConclusionIvabradine safely and significantly lowers HR and improves HR variability in patients with systolic heart failure, without inducing significant bradycardia, ventricular arrhythmias, or supraventricular arrhythmias.
Synthesis and Characterization of 4‐, 5‐, and 6‐Coordinate Tris(1‐ethyl‐4‐isopropylimidazolyl‐κN)phosphine Cobalt(II) Complexes
Authors: Easley Chanel R. , Li Jia , Banerjee Atanu , Panda Manashi , Brennessel William W. , Loloee Reza , Colacio Enrique , Chavez Ferman A. 
Published: March 2015

AbstractThe synthesis and characterization of [Co(T1Et4iPrIP)X2] {T1Et4iPrIP = tris(1‐ethyl‐4‐isopropylimidazolyl)phosphine; X = OTf– (1), Cl– (2), Br– (3)} and [Co(T1Et4iPrIP)(CH3CN)3](OTf)2 (4) were investigated. In compounds 1 and 4, T1Et4iPrIP binds in a tridentate fashion, whereas 2 and 3 feature bidentate ligation. Compound 1 additionally coordinates two triflate ligands to complete a distorted square pyramidal geometry. Compound 4 also binds three acetonitrile ligands to afford a distorted octahedral geometry. Compounds 2 and 3 exhibit a distorted tetrahedral geometry for which the ligands comprise two imidazole nitrogen atoms and two halides. Bidentate coordination by using a tris(imidazolyl)phosphine ligand is unprecedented. Compounds 2 and 3 can be derived from 1 by the addition of either Cl– or Br– salts, respectively, whereas 4 can be generated by dissolving 1 in acetonitrile. DFT studies indicate that the HOMO–LUMO gaps of all compounds are comparable; however, steric factors stabilize the formation of 2 and 3 over 1 in the presence of halide ligands.
Dithiooxamide as an Effective Sulfur Surrogate for Odorless High‐Yielding Carbon–Sulfur Bond Formation in Wet PEG200 as an Eco‐Friendly, Safe, and Recoverable Solvent
Authors: Firouzabadi Habib , Iranpoor Nasser , Gorginpour Forough , Samadi Arash 
Published: March 2015

AbstractIn this study, we have employed dithiooxamide, a solid, odorless, and commercially available compound, as a sulfur surrogate for the preparation of dialkyl sulfides from available alkyl halides in high yields. This sulfur transfer agent was also used for a copper‐catalyzed high‐yielding preparation of diaryl sulfides from their available aryl halides and for the preparation of thia‐Michael adducts in high yields. All the reactions were performed under odorless conditions in wet PEG200 (PEG = polyethylene glycol), which is an eco‐friendly, safe, and recoverable solvent. The protocols were easily applicable to large‐scale operation.
Iodine‐Doped Cobalt Phthalocyanine Supported on Multiwalled Carbon Nanotubes for Electrocatalysis of Oxygen Reduction Reaction
Authors: Nyoni Stephen , Mashazi Philani , Nyokong Tebello 
Published: March 2015

Abstract4‐(4,6‐Diaminopyrimidin‐2‐ylthio) phthalocyaninatocobalt(II) (CoPyPc) was iodine doped, and its electrocatalytic properties explored. Physical characterization techniques such as UV‐vis, X‐ray photoelectron, electron paramagnetic resonance and infra‐red spectroscopy were used. Cyclic voltammetry, electrochemical impedance spectroscopy and rotating disk electrode were used for electrochemical characterization of electrodes modified with the prepared phthalocyanine and its nanocomposites. The electrocatalytic effect of a new iodine‐doped cobalt phthalocyanine derivative supported on multiwalled carbon nanotubes was then investigated towards oxygen reduction reaction. The electrocatalytic activity of the iodine‐doped cobalt phthalocyanine was found to be superior in terms of current over the undoped phthalocyanine nanocomposite.
A Novel Strategy of Electrochemically Treated ZrOCl2 Doped Carbon Paste Electrode for Sensitive Determination of Daidzein
Authors: Li Ying , Li Yinfeng , Gao Jian , Wang Lu , Zou Lina , Ye Baoxian 
Published: March 2015

AbstractA novel electrochemically treated ZrOCl2 doped carbon paste composite electrode was easily prepared by directly incorporating ZrOCl2 into graphite powder after with an electrochemical treatment for the first time. This sensor showed sensitive voltammetric sensing for daidzein. The surface morphology and electrochemical properties of the electrode were investigated by scanning electron microscopy and cyclic voltammetry. The electrochemical behavior of daidzein was investigated in detail. Under the optimized conditions, the response currents were linearly related to daidzein concentrations in the range of 3×10−8 to 2×10−6 mol L−1 with a detection limit of 1×10−8 mol L−1 in phosphate buffer solution with pH 2.5. The proposed sensor was also applied to the determination of daidzein in pueraria, pharmaceutical preparations and human uric sample with satisfactory results.
Modified Glassy Carbon Rotating Disk Electrode for Determination of Heterogeneous Reaction Rate Constant of H2O2 Decomposition
Authors: Amirfakhri Seyed Javad , Meunier Jean‐Luc , Berk Dimitrios 
Published: March 2015

AbstractModified glassy carbon RDE method is introduced in this work for the determination of heterogeneous reaction rate constant of H2O2 decomposition. This method is based on the analysis of RDE voltammograms of H2O2 reduction on a glassy carbon electrode covered with a catalyst layer. As a case study, the rate constant of H2O2 decomposition on nitrogen doped graphene is determined by using both glassy carbon and gold RDE methods. A good agreement is observed between the results of these two methods indicating the reliability of the glassy carbon method. Moreover, advantages and limitations of the glassy carbon method are discussed.
Omne Vivum Ex Vivo … Omne? How to Feed an Inanimate Evolvable Chemical System so as to Let it Self‐evolve into Increased Complexity and Life‐like Behaviour
Authors: Strazewski Peter 
Published: March 2015

Abstract“What I cannot create, I do not understand.” Richard Feynman’s bon mot seems almost tailored for experimental systems chemists to realise an important step in the chemical sciences: the creation of living synthetic cells from the entirely inanimate. The underlying idea needs to be simple so the system can develop naturally. This proposal aims at the realisation, viz. finding sets of experimentally feasible initial conditions, exploring varied compositions and analysing their outcomes, of a fully synthetic chemical micro‐compartmented and evolvable macromolecular system being fed with monomers and small molecular weight, high energy compounds, to keep the system permanently out of thermodynamic equilibrium and let it self‐evolve, thus gaining: 1) import‐export control of macromolecules across the compartment membranes; 2) food‐dependent increase in macromolecular size, i.e., polymer length inside the compartments; 3) sustained production of new macromolecules through the establishment of a (or several) de novo genetic code(s); leading to 4) the emergence of replicating macromolecular populations; and 5) the emergence of self‐evolved synthetic living cells.