bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of glucose/xylose cofermentation of poplar hydrolysates processed by different pretreatment technologies
Authors: Lu Yulin , Warner Ryan , Sedlak Miroslav , Ho Nancy , Mosier Nathan S. 
Published: March 2009

AbstractThe inhibitory effects of furfural and acetic acid on the fermentation of xylose and glucose to ethanol in YEPDX medium by a recombinant Saccharomyces cerevisiae strain (LNH‐ST 424A) were investigated. Initial furfural concentrations below 5 g/L caused negligible inhibition to glucose and xylose consumption rates in batch fermentations with high inoculum (4.5–6.0 g/L). At higher initial furfural concentrations (10–15 g/L) the inhibition became significant with xylose consumption rates especially affected. Interactive inhibition between acetic acid and pH were observed and quantified, and the results suggested the importance of conditioning the pH of hydrolysates for optimal fermentation performance. Poplar biomass pretreated by various CAFI processes (dilute acid, AFEX, ARP, SO2‐catalyzed steam explosion, and controlled‐pH) under respective optimal conditions was enzymatically hydrolyzed, and the mixed sugar streams in the hydrolysates were fermented. The 5‐hydroxymethyl furfural (HMF) and furfural concentrations were low in all hydrolysates and did not pose negative effects on fermentation. Maximum ethanol productivity showed that 0–6.2 g/L initial acetic acid does not substantially affect the ethanol fermentation with proper pH adjustment, confirming the results from rich media fermentations with reagent grade sugars. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Substance misuse amongst young people in non‐school settings: challenges to practitioners and policy makers
Authors: McCrystal Patrick 
Published: March 2009

AbstractOver the past two decades the levels of substance misuse amongst children and young people have increased at a global level generally and within the UK in particular. Some school aged young people are considered to be at an increased risk to substance misuse, particularly those outside mainstream school. However, the literature on substance use by these young people remains comparatively limited. This paper explores this issue through an investigation of cannabis use trends amongst the High Risk Booster Sample of the Belfast Youth Development Study, a longitudinal study of adolescent substance use. It focuses upon the cannabis use patterns of young people excluded from school and those attending Emotional and Behavioural Difficulty units from the age of 11–16 years, groups who are historically categorised as vulnerable to substance misuse. The experience of these young people provides evidence to highlight the contemporary challenges facing policy makers and practitioners when addressing substance use and misuse use amongst these young people. Copyright © 2009 John Wiley & Sons, Ltd.
X‐Ray Structure Investigation of (20S)‐20‐O‐β‐D‐Glucopyranosyl‐protopanaxadiol and Antitumor Effect on Lewis Lung Carcinoma in vivo
Authors: Zhou Wei , Feng Meiqing , Li Xinwei , Yan Qin , Zhou Chaoqun , Li Jiyang , Zhou Pei 
Published: March 2009

Abstractmagnified image(20S)‐20‐O‐β‐D‐Glucopyranosyl‐protopanaxadiol (1) has been isolated as a metabolite of ginseng saponins by Paecilomyces bainier. The compound crystallizes in the monoclinic space group P21 with unit cell parameters a=11.523(6) Å, b=12.383(6) Å, c=14.233(7) Å, β=96.862(9)°, and Z=2. The crystal structure has been solved by direct methods and refined to R=0.0536 for 4569 observed reflections. In the crystal structure, the water and methanol molecules link the molecules into infinite supramolecular layers through hydrogen bonds. The antitumor property of 1 was tested in vivo towards the inhibition of Lewis lung carcinoma growth. The results indicated that the antitumor effect of 1 was ordinary on monotherapy. However, comparing the antitumor activity of 1 plus cyclophosphamide (CTX) with that of CTX alone, the combination effect was significantly superior and synergistic. This may due to immunoloregulation activity of 1 by improving the WBC, IL‐2 and INF‐γ degraded by CTX.
Secondary Metabolites in Bryophytes: An Ecological Aspect
Authors: Xie Chun‐Feng , Lou Hong‐Xiang 
Published: March 2009

Abstractmagnified imageBryophytes frequently grow in an unfavorable environment as the earliest land plants, and inevitably biosynthesize secondary metabolites against biotic or abiotic stress. They not only defend against the plant competition, microbial attack, and insect or animal predation, but also function in UV protection, drought tolerance, and freezing survival. This review covers the ecological aspect of secondary metabolites in bryophytes and is taxonomically presented according to the ecological significances.
Screening of Volatile Composition of Lavandula hybridaReverchon II Honey Using Headspace Solid‐Phase Microextraction and Ultrasonic Solvent Extraction
Authors: Jerković Igor , Marijanović Zvonimir 
Published: March 2009

Abstractmagnified imageThe volatiles of unifloral Lavandula hybrida Reverchon II honey were isolated by means of headspace solid‐phase microextraction (HS‐SPME) and ultrasonic solvent extraction (USE) and analyzed by gas chromatography and mass spectrometry (GC, GC/MS). A total of 23 compounds were identified in the headspace with hexan‐1‐ol, hexanal, acetic acid, hotrienol, and 2‐phenylacetaldehyde as the principal components. Three solvents of different polarity were used for USE, and a total of 53 compounds were identified. The extracts with pentane/Et2O 1 : 2 (v/v) were the most representative for USE method containing the majority of the honey floral origin compounds and potential biomarkers (hexanol, acetic acid, butane‐1,3‐diol, butane‐2,3‐diol, benzoic acid, coumarin, and 2‐phenylacetic acid). The total number of identified compounds (USE and HS‐SPME) was 59. In general, the comparison with volatiles of other lavandin honeys of different geographic origins indicated several similarities, while acetic and formic acids were identified with high percentages in L. hybrida Reverchon II honey.
Cellular Automata Models of the Influences on Solute Diffusion through Water
Authors: Kier Lemont B. , Cheng Cho‐Kun , Nelson Jean D. 
Published: March 2009

Abstractmagnified imageA cellular automata (CA) model of liquid water has been used to study self‐diffusion and the diffusion of a solute. The influences of temperature and solute hydropathic state are modeled as variables in this process. The self‐diffusion model correlates very well with earlier experimental data. The diffusion of a solute experiences variation with temperature and its hydropathic states. These influences are found to relate to models of free hydroxy groups and the average cavity cluster size in bulk water. These preliminary models serve as the basis for modeling solute diffusion for specific contaminants of interest (such as heavy metals like uranium) in a water system, and addressing its migration patterns with water relative to temperature.
Simulations in Evolution. II. Relative Fitness and the Propagation of Mutants
Authors: Testa Bernard , Bojarski Andrzej J. 
Published: March 2009

Abstractmagnified imageIn Neo‐Darwinism, variation and natural selection are the two evolutionary mechanisms which propel biological evolution. Our previous article presented a histogram model [1] consisting in populations of individuals whose number changed under the influence of variation and/or fitness, the total population remaining constant. Individuals are classified into bins, and the content of each bin is calculated generation after generation by an Excel spreadsheet. Here, we apply the histogram model to a stable population with fitness F1=1.00 in which one or two fitter mutants emerge. In a first scenario, a single mutant emerged in the population whose fitness was greater than 1.00. The simulations ended when the original population was reduced to a single individual. The histogram model was validated by excellent agreement between its predictions and those of a classical continuous function (Eqn. 1) which predicts the number of generations needed for a favorable mutation to spread throughout a population. But in contrast to Eqn. 1, our histogram model is adaptable to more complex scenarios, as demonstrated here. In the second and third scenarios, the original population was present at time zero together with two mutants which differed from the original population by two higher and distinct fitness values. In the fourth scenario, the large original population was present at time zero together with one fitter mutant. After a number of generations, when the mutant offspring had multiplied, a second mutant was introduced whose fitness was even greater. The histogram model also allows Shannon entropy (SE) to be monitored continuously as the information content of the total population decreases or increases. The results of these simulations illustrate, in a graphically didactic manner, the influence of natural selection, operating through relative fitness, in the emergence and dominance of a fitter mutant.
Balloon dilation of pulmonary valve stenosis in infants less than 3 kg: A 20‐year experience
Authors: Karagoz Tevfik , Asoh Kentaro , Hickey Edward , Chaturvedi Rajiv , Lee Kyong‐Jin , Nykanen David , Benson Lee 
Published: March 2009

AbstractObjectives: This study focused on the anatomical features and outcomes of percutaneous pulmonary valve balloon dilation (PVD) in newborns ≤3 kg in weight. Background: Although PVD is the treatment of choice for isolated pulmonary valve stenosis, there are no studies detailing technical, anatomical, and outcome variables in the smallest of infants undergoing the procedure. Methods: A retrospective, consecutive review of all initial and follow‐up echocardiograms, catheterization data, cineangiograms, and surgical records of all neonates less than 3 kg. Results: Fifty infants underwent 55 PVD's, median age 7 days and weight 2.7 kg. Congestive heart failure and/or cyanosis were present in 55%, 46% prostaglandin dependent, with 28% having a hypoplastic right ventricle. The pulmonary valve diameter median z‐score was −2.6, (range −5.8 to 1.2, P < 0.0001 vs. normal). The procedure was accomplished in all but one child, using a balloon to annulus ratio of 1.3 (range 1.1 to 1.7). There was a reduction in both the peak right ventricular systolic pressure (P < 0.0001) and outflow gradient (P < 0.0001). There was no procedure related mortality, although six children died in long‐term follow‐up (14%). Reintervention was necessary in 15 infants within 8 months of the procedure. Pulmonary regurgitation, present in 36% after the procedure, showed a gradual increase over time while outflow gradients decreased and valve annular dimensions increased toward normal. Conclusions: In infants ≤3 kg, PVD is safe and effective. A large proportion remains free from surgery (76% at 10 years). Small valve annular dimensions show catch up growth with time. © 2009 Wiley‐Liss, Inc.
Radial versus femoral approach for high‐speed rotational atherectomy
Authors: Watt Jonathan , Oldroyd Keith G. 
Published: March 2009

AbstractObjective: The aim of this study was to compare in‐hospital outcomes for patients undergoing high‐speed rotational atherectomy (HSRA) via the radial and femoral route. Background: Transradial access is often avoided for HSRA because of concern over limitations on guide catheter size. No studies have compared a radial and femoral approach for HSRA. Methods: This is a retrospective comparison of in‐hospital outcomes for 151 consecutive patients (75 radial, 76 femoral) undergoing HSRA. Results: Significantly smaller diameter guide catheters (6.3 ± 0.5 Fr vs. 7.1 ± 0.8 Fr, P < 0.001) and burrs (1.6 ± 0.2 mm vs. 1.7 ± 0.2 mm, P = 0.02) were used in the radial compared with the femoral group. Procedural success (93.3% vs. 94.7%, P = 0.75), procedure time (108.7 ± 30.5 min vs. 112.8 ± 35.0 min, P = 0.45), and patient radiation exposure (12125 ± 8373 vs. 12118 ± 7831 cGy cm2, P = 1.00) were similar in radial and femoral groups. There was a trend in favor of radial artery access for major access site bleeding complications (0.0% vs. 5.3%, P = 0.12). The incidence of in‐hospital death or myocardial infarction was low in both groups. Conclusion: This study shows that radial artery access is a feasible, safe, and effective approach for HSRA. Overall complication rates are low and radial access may be associated with a lower risk of major bleeding complications compared with a femoral approach. © 2009 Wiley‐Liss, Inc.
Semipreparative HPLC enantioseparation, chiroptical properties, and absolute configuration of two novel cyclooxygenase‐2 inhibitors
Authors: Cirilli Roberto , Fiore Stefano , La Torre Francesco , Maccioni Elias , Secci Daniela , Sanna Maria Luisa , Faggi Cristina 
Published: March 2009

AbstractA direct semipreparative HPLC enantioseparation of two chiral thiazolidinone derivatives having cyclooxygenase‐2 inhibition activity was performed on the Chiralpak IA chiral stationary phase. Semipreparative amounts of enantiopure forms were collected using acetonitrile‐ethanol‐trifluoroacetic acid mixtures as mobile phase. The absolute configuration of both compounds was unequivocally established by single‐crystal X‐ray diffraction method and correlated to the chiroptical properties of isolated enantiomers. Chirality, 2010. © 2009 Wiley‐Liss, Inc.
Estimation of thermodynamically consistent reaction rate coefficients
Authors: Anselmo Kenneth J. , Upadhye Ravindra S. 
Published: March 2009

AbstractThis note points out the importance of incorporating thermodynamic constraints in phenomenological models of cyclic reaction networks. We present a case study where the parameters of the postulated model are estimated with and without the necessary constraints, and show that ignoring the constraints can cause thermodynamically inconsistent parametric estimates.
Behavior of fine particles in a spouted bed consisting of fine and coarse particles
Authors: Ishikura T. , Shinohara H. , Tanaka I. 
Published: March 2009

AbstractThe elutriation of fines from a spouted bed of fine and coarse particles has been studied. Equations for correlating elutriation rate coefficients are proposed. Three different regions associated with particle behavior have been identified in a way to permit calculation of elutriation rate at any column height. Measurements of cross‐sectionally averaged holdup of particles and local particle velocity have been used to interpret the decrease in elutriation rate along the freeboard. The known concept of a Transport Disengaging Height (T.D.H.) has been employed.
Differential thermal analysis of reaction kinetics in pseudo‐isothermal state Part 1. Simple reaction
Authors: Matsuda Hitoki , Goto Shigeo 
Published: March 2009

AbstractA new method for the evaluation of kinetic parameters is proposed, in which differential thermal analysis (DTA) is carried out under psuedo‐isothermal conditions, that is, both sample and reference materials are not heated and the temperatures remain as isothermal as possible. The hydrolysis of acetic anhydride was used as a model of simple reaction for the DTA experiment. The kinetic parameters such as the rate constant, the heat of reaction and the activation energy, evaluated from the proposed method were in good agreement with those obtained from conventional titration measurements. Systematic errors in the rate constant evaluation are discussed in order to enable the kinetic parameters to be evaluated accurately.
Computation of the near‐optimal temperature and initiator policies for a batch polymerization reactor
Authors: Thomas Isabelle M. , Kiparissides Costas 
Published: March 2009

AbstractOptimal control theory is applied to a batch polymerization reactor for PMMA to calculate the near‐optimal temperature and initiator policies that are required to produce a polymer with a desired final conversion, and desired number average and weight average molecular weights. The two‐point boundary value problem that results from the application of the Pontryagin minimum principle to the mathematical model of the reactor is solved by the discretization control method. According to this, the total reaction time is divided into N equal subintervals. It is assumed that the control variables remain constant in each interval and the Hamiltonian is minimized by a first‐order gradient technique. It is shown that the introduction of the “target set” concept, which is well suited to industrial practice, simplifies the numerical solution of the TPBV problem. Results of the simulations demonstrate the potential gains possible from the application of the optimal control theory to the batch polymerization of PMMA.
On the mechanism of hydrodeoxygenation of ortho substituted phenols
Authors: Furimsky E. , Mikhlin J.A. , Jones D.Q. , Adley T. , Baikowitz H. 
Published: March 2009

AbstractHydrodeoxygenation reactivities of four ortho‐substituted phenols and of the unsubstituted phenol were compared at 350°C in the presence of a cobalt molybdate catalyst. The order of reactivities was established as: tert‐butyl phenol >phenol >methyl phenol> ethyl phenol >dimethyl phenol.The order of resistance of phenolic rings to hydrogenation was observed as: dimethyl phenol methyl phenol >ethyl phenol >tert butyl phenol >phenol.
Evolutionary synthesis method of energy integrated distillation separation process
Authors: Muraki Masaaki , Hayakawa Toyohiko 
Published: March 2009

AbstractA two‐stage evolutionary method is developed to synthesize an optimal energy integrated distillation separation process: the search of the separation sequence, and the introduction of energy integration to the given separation sequence. For the former an evolutionary procedure first generating initial separation sequences and then evolving them is developed. For the latter an evolutionary procedure, first indicating the direction of the evolution by the thermodynamic analysis and then estimating it based on the objective function, is developed. An example problem of a five‐component separation demonstrates the effectiveness of this proposed method.
Measurement of band emissivity of porous spheres at high temperatures
Authors: Barua S. K. , Wynnyckyj J. R. , Rankin W. J. 
Published: March 2009

AbstractA relatively simple technique has been developed to measure the band emissivity of spherical solids at high temperatures. The technique involves measuring the surface temperature of a sphere when in thermal equilibrium with a furnace enclosure, followed by isolating it from the enclosure by means of a shield. The emissivity is evaluated from the drop in energy flux from the pellet consequent upon changing the enclosure from an effectively black‐body to a freely radiating one. The value of the band emissivity is validated by simulating the experimental cooling curve using independently measured values of the effective thermal conductivity and total emissivity of the solid to obtain internal consistency. In this way highly accurate values of band emissivity are obtained.The technique was applied to pellets of both reacted and unreacted mixtures of calcined‐dolomite and silicon, as used in the commercial production of magnesium.
Effect of gas sparging on the rate of mass transfer at fixed beds of horizontally stacked screens
Authors: Katkout F. A. , Zatout A. A. , Farag H. A. , Sedahmed G. H. 
Published: March 2009

AbstractRates of mass transfer at air sparged fixed beds of stacked screens were measured by an electrochemical technique. Variables studied were air superficial velocity, physical properties of the solution and bed thickness. The liquid mass transfer coefficient was found to increase with air superficial velocity up to a certain point and then remain almost constant with further increase in velocity. The increase in the mass transfer coefficient as a result of air sparging ranged from 2.8 to 10 times the natural convection value depending on the operating conditions. Increasing bed thickness was found to decrease the mass transfer coefficient at a given air superficial velocity. Mass transfer data at fixed beds were correlated by the equation:j = 0.268 (Re · Fr)−0.25 (L/d)−0.35.For a single horizontal screen the data were correlated by the equation:j = 0.275 (Re · Fr)−0.21.
A Simple quasi‐steady analysis of turbulent flow freezing transients and comparison with experiments
Authors: Thomason S. B. , Mulligan J. C. , Hill J. M. 
Published: March 2009

AbstractA simple quasi‐steady analysis is developed to predict transient heat transfer and pressure drop as an internal turbulent flow freezes when tube‐wall temperature is suddenly lowered. Heat transfer correlations by Sparrow‐Hallman‐Siegel and Kays, and the Blasius friction relation are modified for this analysis. Experimental data are compared and reasonable agreement exists when relatively uniform tube‐wall temperatures existed in the experimental apparatus; and indications are that the ice was of minimal thickness under those conditions. Analytical predictions did not agree well with experiments when the tube‐wall temperatures in the apparatus exhibited significant nonuniformity, or when thick frozen shells existed.
Catalyst mixing in bubble column slurry reactors
Authors: Chidambaram M. 
Published: March 2009

AbstractThe reported experimental data of Pandit and Joshi (1984) on axial and radial steady‐state catalyst concentration in a semibatch bubble column slurry reactor is interpreted by the dispersion model. The elliptic partial differential equation with its associated boundary conditions is solved analytically for catalyst concentration by the method of separation of variables. The proposed model adequately fits the experimental data.
Free convection heat transfer over a horizontal plate at low prandtl number
Authors: Singh P. , Narayan K. A. 
Published: March 2009

AbstractBoundary layer equations for free convection heat transfer along a semi‐infinite horizontal plate are derived by giving more importance to the energy equation. The equations are obtained for low Prandtl number and two separate polynomials are used to approximate the temperature and velocity profiles in these regions. The rate of heat transfer is compared with the available analytical and numerical results based on conventional boundary layer equations.
A magic angle spinning 27A1 NMR study of the adsorption of CL2 on γ‐alumina
Authors: Rohner Markus Ch. , Sharma Virendra K. , Richarz Werner 
Published: March 2009

AbstractMagic angle spinning 27Al NMR studies of a γ‐alumina show that the proportion of octahedrally coordinated aluminum ions increases after the adsorption of gaseous chlorine. The relative increase of the octahedrally coordinated aluminum ions is greater at higher temperatures and occurs due to preferential conversion of the tetrahedrally coordinated aluminum ions in the surface.
Modelling of butene‐1 dehydrogenation in a fixed bed reactor — bed and pellet profiles
Authors: Acharya D. R. , Hughes R. 
Published: March 2009

AbstractA homogeneous model incorporating the Dumez & Froment kinetics has been proposed for the butene‐1 dehydrogenation reaction over a commercial chromia‐alumina catalyst. The model predicts bed and pellet concentration and temperature profiles. While the temperature profiles obtained suggest a temperature minimum in the reactor, the pellet remains nearly isothermal. Under the condition used in this study, a series type of coke deposition is obtained. A comparison between experimental results obtained using the neutron attenuation technique and theoretical coke profiles reveals excellent agreement and confirms the validity of the model and the kinetics employed.