bluuebunny/crossref_metadata_2025_split huggingface dataset:
Canopy edge flow: A momentum balance analysis
Authors: Moltchanov Sharon , Bohbot‐Raviv Yardena , Duman Tomer , Shavit Uri 
Published: February 2015

AbstractCanopy flow models are often dedicated to ideal, infinite, homogenous systems. However, real canopy systems have physical boundaries, where the flow enters and leaves patches of vegetation, generating a complex pressure field and velocity variations. Here we focus our study on the canopy entry region by examining the terms involved in the double (space and time) averaged momentum equations and their relative contribution to the total momentum balance. The estimation of each term is made possible by particle image velocimetry (PIV) measurements in a model canopy constructed of randomly distributed thin glass plates. The instantaneous velocity fields were used to calculate the mean velocities, pressure, drag, Reynolds stresses, and dispersive stresses. It was found that within the entry region, the pressure gradient, the drag forces, and dispersive stresses are the three most significant terms that affect the balance in the streamwise momentum equation. In the vertical direction, the dispersive stresses are also significant and their contribution to the total momentum cannot be ignored. The study shows that dispersive stresses are initially formed around canopy edges; at both the entry region and the canopy top boundary. They start as a sink term, extracting momentum from the flow, and then become a source term that contributes momentum to the flow until they eventually decay at some short penetration distance into the canopy. These results reveal a new understanding on the evolution of momentum within the entry region, necessary in any closure modeling of flow in real canopies.
Prolonged river water pollution due to variable‐density flow and solute transport in the riverbed
Authors: Jin Guangqiu , Tang Hongwu , Li Ling , Barry D. A. 
Published: February 2015

AbstractA laboratory experiment and numerical modeling were used to examine effects of density gradients on hyporheic flow and solute transport under the condition of a solute pulse input to a river with regular bed forms. Relatively low‐density gradients due to an initial salt pulse concentration of 1.55 kg m−3 applied in the experiment were found to modulate significantly the pore‐water flow and solute transport in the riverbed. Such density gradients increased downward flow and solute transport in the riverbed by factors up to 1.6. This resulted in a 12.2% increase in the total salt transfer from the water column to the riverbed over the salt pulse period. As the solute pulse passed, the effect of the density gradients reversed, slowing down the release of the solute back to the river water by a factor of 3.7. Numerical modeling indicated that these density effects intensified as salt concentrations in the water column increased. Simulations further showed that the density gradients might even lead to unstable flow and result in solute fingers in the bed of large bed forms. The slow release of solute from the bed back to the river led to a long tail of solute concentration in the river water. These findings have implications for assessment of impact of pollution events on river systems, in particular, long‐term effects on both the river water and riverbed due to the hyporheic exchange.
Iterative learning control for nonlinear dynamic systems with randomly varying trial lengths
Authors: Li Xuefang , Xu Jian‐Xin , Huang Deqing 
Published: February 2015

SummaryIn this paper, we introduce an iterative learning control (ILC) scheme based on an iteratively moving average operator for nonlinear dynamic systems with randomly varying trial lengths. By using the iteratively moving average operator, the proposed ILC algorithm overcomes the limitation of traditional ILC that all trial lengths must be identical. It is shown that for nonlinear affine and non‐affine systems, the proposed learning algorithm works effectively to nullify the tracking error. In the end, two illustrative examples are presented to demonstrate the performance and the effectiveness of the proposed ILC scheme for nonlinear dynamic systems. Copyright © 2015 John Wiley & Sons, Ltd.
Synthesis and Characterization of New Polyureas with Improved Thermal Stability from a Novel Ether Keto Diamine
Authors: Esfahanizadeh Mahshid , Sabbaghian Elahe , Mehdipour‐Ataei Shahram , Jalilian Seyedmehrdad , Babanzadeh Samal 
Published: February 2015

ABSTRACTA novel diamine monomer was prepared in three steps: first, a nucleophilic substitution reaction between hydroquinone and 1‐flouro‐4‐nitrobenzene afforded a nitro compound. Second, the nitro group of this compound was converted to an amino group via reduction in the presence of hydrazine hydrate. In the last step, the reaction of this compound with 4,4'‐diflouro benzophenone led to the synthesis of a novel ether keto diamine. Characterization of all materials was carried out by conventional spectroscopic methods and elemental analysis. A series of new polyureas was prepared via the polymerization reaction of the synthesized diamine with three commercially available diisocyanates including 4,4'‐diphenylmethan diisocyanate, toluene‐2,4‐diisocyanate, and isophoronediisocyanate in N‐methyl‐2‐pyrrolidone. The resulted polyureas were characterized by infrared spectroscopy and elemental analysis. The inherent viscosities of these polyureas ranged from 0.59 to 0.62 dL/g measured at a concentration of 0.5 g/dL. The resulting polyureas were soluble in dipolar aprotic solvents. The thermal properties of the polymers were investigated by differential scanning calorimetry and thermogravimetric analysis. The results indicated that their glass transition temperature values were between 171 and 198°C and at the 10% weight loss of polymers, glass transition temperature was about 325–368°C showing improved thermal stability in comparison with common polyureas. Thermal stability features of the polyurea were also confirmed by means of the pyrolysis‐gas chromatography/mass spectrometry method.
An Efficient and Green Synthesis of 1‐Indanone and 1‐Tetralone via Intramolecular Friedel–Crafts Acylation Reaction
Authors: Tran Phuong Hoang , Huynh Vy Hieu , Hansen Poul Erik , Chau Duy‐Khiem Nguyen , Le Thach Ngoc 
Published: February 2015

AbstractMetal‐triflate‐catalyzed intramolecular Friedel–Crafts acylation of 3‐arylpropanoic and 4‐arylbutanoic acids in triflate‐anion ionic liquids under monomodal microwave irradiation is reported. The environmentally benign synthetic procedure allows the formation of cyclic ketones in good yields within a short reaction time. The catalytic metal triflate in triflate‐anion ionic liquids can be easily recovered and reused several times without significant loss of the catalytic performance.
Cu3(hexaiminotriphenylene)2: An Electrically Conductive 2D Metal–Organic Framework for Chemiresistive Sensing
Authors: Campbell Michael G. , Sheberla Dennis , Liu Sophie F. , Swager Timothy M. , Dincă Mircea 
Published: February 2015

AbstractThe utility of metal–organic frameworks (MOFs) as functional materials in electronic devices has been limited to date by a lack of MOFs that display high electrical conductivity. Here, we report the synthesis of a new electrically conductive 2D MOF, Cu3(HITP)2 (HITP=2,3,6,7,10,11‐hexaiminotriphenylene), which displays a bulk conductivity of 0.2 S cm−1 (pellet, two‐point‐probe). Devices synthesized by simple drop casting of Cu3(HITP)2 dispersions function as reversible chemiresistive sensors, capable of detecting sub‐ppm levels of ammonia vapor. Comparison with the isostructural 2D MOF Ni3(HITP)2 shows that the copper sites are critical for ammonia sensing, indicating that rational design/synthesis can be used to tune the functional properties of conductive MOFs.
Industrial melt index prediction with the ensemble anti‐outlier just‐in‐time Gaussian process regression modeling method
Authors: Liu Yi , Gao Zengliang 
Published: February 2015

ABSTRACTSeveral data‐driven soft sensors have been applied for online quality prediction in polymerization processes. However, industrial data samples often follow a non‐Gaussian distribution and contain some outliers. Additionally, a single model is insufficient to capture all of the characteristics in multiple grades. In this study, the support vector clustering (SVC)‐based outlier detection method was first used to better handle the nonlinearity and non‐Gaussianity in data samples. Then, SVC was integrated into the just‐in‐time Gaussian process regression (JGPR) modeling method to enhance the prediction reliability. A similar data set with fewer outliers was constructed to build a more reliable local SVC–JGPR prediction model. Moreover, an ensemble strategy was proposed to combine several local SVC–JGPR models with the prediction uncertainty. Finally, the historical data set was updated repetitively in a reasonable way. The prediction results in the industrial polymerization process show the superiority of the proposed method in terms of prediction accuracy and reliability. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41958.
Phosphor settling induced mechanical degradation of silicone/phosphor composite in light emitting diode packages
Authors: Chen Xing , Wang Simin , Chen Mingxiang , Liu Sheng 
Published: February 2015

ABSTRACTSilicone/phosphor composite is a functional material used in light emitting diode (LED) packages. In this article, effect of phosphor settling on mechanical properties and microstructure of phosphor/silicone composite is investigated experimentally and numerically. Test samples of silicones with various degrees of phosphor settling were prepared and uniaxial tensile tests were conducted. The results indicate that, for specific volume fraction of phosphor, phosphor sedimentation tends to reduce the strength and elongation of overall composite. And with increasing degree of sedimentation, the weakening effect becomes more significant. The fractographs of the test samples indicate that cracks initiate around the bottom area where phosphor particles settle. Numerical investigations, which were conducted by random unit cell model with graded particle distribution, demonstrate that strain localization and stress concentration are significant where phosphor particles concentrate. It can be concluded that, to reduce mechanical degradation, phosphor sedimentation should be minimized in silicone/phosphor composite for LED packages. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42006.
Randomized, Double‐Blind, Dose‐Escalation Trial of Triptorelin for Ovary Protection in Childhood‐Onset Systemic Lupus Erythematosus
Authors: Brunner Hermine I. , Silva Clovis A. , Reiff Andreas , Higgins Gloria C. , Imundo Lisa , Williams Calvin B. , Wallace Carol A. , Aikawa Nadia E. , Nelson Shannen , Klein‐Gitelman Marisa S. , Rose Susan R. 
Published: February 2015

ObjectiveTo determine the dose of triptorelin that is sufficient to maintain complete ovarian suppression in female patients with childhood‐onset systemic lupus erythematosus (SLE) who require cyclophosphamide therapy, to determine the length of time needed to achieve ovarian suppression after initiation of triptorelin treatment, and to investigate the safety of triptorelin.MethodsIn this randomized, double‐blind, placebo‐controlled, dose‐escalation study, female patients ages <21 years were randomized 4:1 to receive triptorelin (n = 25) or placebo (n = 6). The starting doses of triptorelin were 25, 50, 75, and 100 μg/kg, and the dose was escalated until complete ovarian suppression was maintained. The primary outcome was the weight‐adjusted dose of triptorelin that provided complete ovarian suppression in at least 90% of the patients, as determined by gonadotropin‐releasing hormone agonist stimulation testing. The secondary outcome was the period of time required to achieve ovarian suppression, as measured by unstimulated follicle‐stimulating hormone and luteinizing hormone levels after the initiation of triptorelin treatment.ResultsTreatment with triptorelin at a weight‐adjusted dose of 120 μg/kg body weight provided sustained complete ovarian suppression in 90% of the patients. After administration of the initial dose of triptorelin, 22 days were required to achieve complete ovarian suppression. The rates of adverse events (AEs) and serious adverse events (SAEs) per 100 patient‐months of followup were not higher in the triptorelin group compared with the placebo group (for AEs, 189 versus 362; for SAEs, 2.1 versus 8.5).ConclusionHigh doses of triptorelin are needed to achieve and maintain complete ovarian suppression, but such doses appear to be well tolerated in adolescent female patients with childhood‐onset SLE. Our data suggest that a lag time of 22 days after initiation of triptorelin treatment is required before cyclophosphamide therapy is started or continued.
Nitrate reductase, nitrite reductase, glutamine synthetase, and glutamate synthase expression and activity in response to different nitrogen sources in nitrogen‐starved wheat seedlings
Authors: Balotf Sadegh , Kavoosi Gholamreza , Kholdebarin Bahman 
Published: February 2015

AbstractThe objective of this study was to examine the expression and activity of nitrate reductase (NR, EC 1.7.1.1), nitrite reductase (NiR, EC 1.7.2.2), glutamine synthetase (GS, EC 6.3.1.2), and glutamate synthase (GOGAT, EC 1.4.7.1) in response to potassium nitrate, ammonium chloride, and ammonium nitrate in nitrogen‐starved wheat seedlings. Plants were grown in standard nutrient solution for 17 days and then subjected to nitrogen starvation for 7 days. The starved plants were supplied with potassium nitrate ammonium nitrate and ammonium chloride (50 mM) for 4 days and the leaves were harvested. The relative expression of NR, NiR, GS, and GOGAT as well as the enzyme activities were investigated. Nitrogen starvation caused a significant decrease both in transcript levels and in NR, NiR, GS, and GOGAT activities. Potassium nitrate and ammonium nitrate treatments restored NR, NiR, GS, and GOGAT expressions and activities. Ammonium chloride increased only the expressions and activities of GS and GOGAT in a dose‐dependent manner. The results of our study highlight the differential effects between the type and the amount of nitrogen salts on NR, NiR, GS, and GOGAT activities in wheat seedlings while potassium nitrate being more effective.
Age Differences in Risk: Perceptions, Intentions and Domains
Authors: Bonem Emily M. , Ellsworth Phoebe C. , Gonzalez Richard 
Published: February 2015

AbstractAlthough it is commonly assumed that older people are more cautious and risk averse than their younger counterparts, the research on age differences in risk taking is mixed. While some research has found that older adults are less risk seeking, other research has found the opposite or no differences. One explanation is that age differences vary across risk domains. In two studies, we surveyed three adult age groups ranging in age from 18 to 83 on their risk perceptions and intentions of risky behaviors across several domains. Our studies showed that compared with young adults, older adults tend to see more risk in behaviors in health and ethical domains but less risk in behaviors from the social domain. A similar pattern occurred for participants' intentions of engaging in the risky behaviors. Older adults rated risky behaviors from health and ethical domains as less enjoyable and less likely to produce gains than young adults, whereas they rated risky behaviors from the social domain as more enjoyable, less unpleasant, and less likely to produce losses than young adults. These results suggest that age differences in risk preferences may vary across domains and may result from differing motivations. Copyright © 2015 John Wiley & Sons, Ltd.
Do Bettors Correctly Perceive Odds? Three Studies of How Bettors Interpret Betting Odds as Probabilistic Information
Authors: Andersson Patric , Nilsson Håkan 
Published: February 2015

AbstractThis paper reports on three studies investigating how accurately bettors (=people who regularly bet on sports events) interpret the probabilistic information implied by betting odds. All studies were based on data collected by web surveys prompting a total of 186 experienced bettors to convert sets of representative odds into frequency judgments. Bayesian statistical methods were used to analyze the data. From the results, the following conclusions were made: (i) On the whole, the bettors produced well‐calibrated judgments, indicating that they have realistic perceptions of odds. (ii) Bettors were unable to consciously adjust judgments for different margins. (iii) Although their interval judgments often covered the estimates implied by the odds, the bettors tended to overestimate the variation of expected profitable bets between months. The results are consistent with prior research showing that people tend to make accurate probability judgments when faced with tasks characterized by constant and clear feedback. Copyright © 2015 John Wiley & Sons, Ltd.
Assessing protein conformational sampling and structural stability via de novo design and molecular dynamics simulations
Authors: Cunha Keila C. , Rusu Victor H. , Viana Isabelle F. T. , Marques Ernesto T. A. , Dhalia Rafael , Lins Roberto D. 
Published: February 2015

ABSTRACTMolecular dynamics and de novo techniques, associated to quality parameter sets, have excelled at determining the structure of small proteins with high accuracy. To achieve a detailed description of protein conformations, these methods must critically assess the thermodynamic features of the molecular ensembles. Here, a comparison of the conformational ensemble generated by molecular dynamics and de novo techniques were carried out for six Top7‐based proteins carrying gp41 HIV‐1 epitopes. The native Top7, a highly stable computationally designed protein, was used as benchmark. Structural stability, flexibility, and secondary structure content were assessed. The consistency of the latter was compared to experimental circular dichroism spectra for all proteins. While both methods are capable to identify the stable from unstable chimeric proteins, the sampled conformational space and flexibility differ significantly in both methods. Molecular dynamics simulations seem to better describe secondary structure content and identify regions responsible for conformational instability. The de novo method, as implemented in Rosetta—a prime tool for protein design, overestimates secondary structure content. On the other hand, its empirical energy function is capable to predict the threshold for protein stability. © 2015 Wiley Periodicals, Inc. Biopolymers 103: 351–361, 2015.
Selective solid‐phase extraction of artificial chemicals from milk samples using multiple‐template surface molecularly imprinted polymers
Authors: Zhang Jing , Ni Yan‐li , Wang Ling‐ling , Ma Jin‐qin , Zhang Zhi‐qi 
Published: February 2015

AbstractA novel multiple‐template surface molecularly imprinted polymer (MTMIP) was synthesized using ofloxacin and 17β‐estradiol as templates and modified monodispersed poly(glycidylmethacrylate‐co‐ethylene dimethacrylate) (PGMA/EDMA) beads as the support material. Static adsorption, solid‐phase extraction and high‐performance liquid chromatography were performed to investigate the adsorption properties and selective recognition characteristics of the polymer templates and their structural analogs. The maximum binding capacities of ofloxacin and 17β‐estradiol on the MTMIP were 9.0 and 6.6 mg/g, respectively. Compared with the corresponding nonimprinted polymer, the MTMIP exhibited a much higher adsorption performance and selectivity toward three quinolones and three estrogens, which are common drug residues in food. The MTMIP served as a simple and effective pretreatment method and could be successfully applied to the simultaneous analysis of multiple target components in complex samples. Furthermore, the MTMIP may find useful applications as a solid‐phase absorbent in the simultaneous determination of trace quinolones and estrogens in milk samples, as the recoveries were in the range 77.6–98.0%. Copyright © 2015 John Wiley & Sons, Ltd.
Purification and characterization of organic solvent stable serine alkaline protease from newly isolated Bacillus circulans M34
Authors: Sari Esma , Loğoğlu Elif , Öktemer Atilla 
Published: February 2015

AbstractA protease from newly isolated Bacillus circulans M34 was purified by Q‐Sepharose anion exchange chromatography and Sepharose–bacitracin affinity chromatography followed by (NH4)2SO4 precipitation. The molecular mass of the purified enzyme was determined using SDS–PAGE. The optimum pH and temperature for protease activity were 11 and 50°C, respectively. The effect of various metal ions on protease activity was investigated. Alkaline protease from Bacillus circulans M34 wase activated by Zn2+, Cu2+ and Co2+ up to 31%. The purified protease was found to be stable in the organic solvents, surfactants and oxidizing agent. The substrate specificity of purified protease was investigated towards different substrates. The protease was almost completely inhibited by the serine protease inhibitor phenylmethanesulfonyl fluoride. The kinetic parameters of the purified protease, maximum rate (Vmax) and Michaelis constant (Km), were determined using a Lineweaver–Burk plot. Copyright © 2015 John Wiley & Sons, Ltd.
Simultaneous quantification of curdione, furanodiene and germacrone in rabbit plasma using liquid chromatography–tandem mass spectrometry and its application to a pharmacokinetic study
Authors: Wang Baolian , Yang Shuang , Sheng Li , Li Yan 
Published: February 2015

ABSTRACTA simple, rapid and sensitive method was developed for the simultaneous quantification of curdione, furanodiene and germacrone in rabbit plasma using a LC‐MS/MS analysis. The plasma sample preparation was a simple deproteinization by the addition of 3 vols of acetonitrile followed by centrifugation. The analytes and internal standard (IS) costunolide were separated on a Zorbax SB‐C18 column (3.5 µm, 2.1 × 100 mm) with mobile phase of methanol–water (90:10, v/v) containing 0.1% formic acid at a flow rate of 0.3 mL/min with an operating temperature of 25°C. Detection was carried out by atmospheric pressure chemical ionization in positive ion selected reaction monitoring mode. Linear detection responses were obtained for the three test compounds ranging from 5 to 5000 ng/mL and the lower limits of quantitation were 5‐10ng/mL. The intra‐ and inter‐day precisions (relative standard deviations) were within 9.4% for all analytes, while the deviation of assay accuracies was within ±10.0%. The average recoveries of analytes were >80.0%. All analytes were proved to be stable during all sample storage, preparation and analytical procedures. The method was successfully applied to the pharmacokinetic study of the three compounds after vaginal drug delivery of Baofukang suppository to rabbit. Copyright © 2015 John Wiley & Sons, Ltd.