bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimating the mean speed of laminar overland flow using dye injection‐uncertainty on rough surfaces
Authors: Dunkerley David 
Published: August 2002

AbstractA common method for estimating mean flow speeds in studies of surface runoff is to time the travel of a dye cloud across a measured flow path. Motion of the dye front reflects the surface flow speed, and a correction must be employed to derive a value for the profile mean speed, which is always lower. Whilst laminar flow conditions are widespread in the interrill zone, few data are available with which to establish the relationship linking surface and profile mean speeds, and there are virtually none for the flow range 100 < Re < 500 (Re = Reynolds number) which is studied here. In laboratory experiments on a glued sand board, mean flow speeds were estimated from both dye speeds and the volumetric flow relation
v = Q/
wd with
d measured using a computer‐controlled needle gauge at 64 points. In order to simulate conditions applicable to many dryland soils, the board was also roughened with plant litter and with ceramic tiles (to simulate surface stone cover). Results demonstrate that in the range 100 < Re < 500, there is no consistent relation between surface flow speeds and the profile mean. The mean relationship is
v = 0·56 v
surf, which departs significantly from the theoretical smooth‐surface relation
v = 0·67 v
surf, and exhibits a considerable scatter of values that show a dependence on flow depth. Given the inapplicability of any fixed conversion factor, and the dependence on flow depth, it is suggested that the use of dye timing as a method for estimating
v be abandoned in favour of precision depth measurement and the use of the relation
v = Q/
wd, at least within the laminar flow range tested. Copyright © 2001 John Wiley & Sons, Ltd.
Mapping the geochemistry of the northern Rub' Al Khali using multispectral remote sensing techniques
Authors: White Kevin , Goudie Andrew , Parker Adrian , Al‐Farraj Asma 
Published: August 2002

AbstractSpatial variations in sand sea geochemistry relate to mixing of different sediment sources and to variations in weathering. Due to problems of accessibility, adequate spatial coverage cannot be achieved using field surveys alone. However, maps of geochemical composition produced from remotely sensed data can be calibrated against limited field data and the results extrapolated over large, inaccessible areas. This technique is applied to part of the Rub' Al Khali in the northern United Arab Emirates. Trend surface analysis of the results suggests that the sand sea at this location can be modelled as an east–west mixing zone of two spectral components: terrestrial reddened quartz sands and marine carbonate sands. Optical dating of these sediments suggests that dune emplacement occurred rapidly around 10 ka BP, when sea level was rising rapidly. The spatial distribution of mineralogical components suggests that this phase of dune emplacement resulted from coastal dune sands being driven inland during marine transgression, thereby becoming mixed with rubified terrestrial sands. Copyright © 2001 John Wiley & Sons, Ltd.
Implications of model uncertainty for the mapping of hillslope‐scale soil erosion predictions
Authors: Brazier Richard E. , Beven Keith J. , Anthony Steven G. , Rowan John S. 
Published: August 2002

AbstractAn integrated modelling approach (MIRSED) which utilizes the process‐based soil erosion model WEPP (Water Erosion Prediction Project) is presented for the assessment of hillslope‐scale soil erosion at five sites throughout England and Wales. The methodology draws upon previous uncertainty analysis of the WEPP hillslope soil erosion model by the authors to qualify model results within an uncertainty framework. A method for incorporating model uncertainty from a range of sources is discussed as a first step towards using and learning from results produced through the GLUE (Generalized Likelihood Uncertainty Estimation) technique. Results are presented and compared to available observed data, which illustrate that levels of uncertainty are significant and must be taken into account if a meaningful understanding of output from models such as WEPP is to be achieved. Furthermore, the collection of quality, observed data is underlined for two reasons: as an essential tool in the development of soil erosion modelling and also to allow further constraint of model uncertainty. Copyright © 2001 John Wiley & Sons, Ltd.
Laboratory simulation of clast abrasion
Authors: Lewin J. , Brewer P. A. 
Published: August 2002

AbstractExperimental abrasion of river‐bed materials has been widely undertaken, producing ‘downstream’ fining rates that generally are believed to be much less than those observed in the field. A conclusion commonly adopted has been that sorting processes are more effective than abrasion processes. A comparative evaluation of results from an abrasion tank and a tumbling barrel are presented, which show that abrasion patterns and rates differ according to the equipment used, clast size and shape, the clast charge (barrel) and water velocity and bed material (tank). Abrasion is a composite process, and the effects achieved appear to be dominated by percussion in the tank and grinding in the barrel. Breakage, crushing and sandblasting are not modelled effectively, nor are effects achieved on clasts when they form part of the bed. Comparisons are made with other equipment used, the very limited amount of direct field abrasion monitoring, and with the probable suite of processes that may occur under field conditions. Also reviewed are the problems that arise when laboratory weight‐loss abrasion coefficients are used or converted into ones of size diminution, as usually derived from field observations of down‐channel trends. It is concluded that field abrasion rates generally have been underestimated, as the processes involved are at best only selectively represented by the experimental equipment so far used, and because the results obtained experimentally are capable of misinterpretation when related to field trends. Copyright © 2002 John Wiley & Sons, Ltd.
Flame retardant properties of EVA‐nanocomposites and improvements by combination of nanofillers with aluminium trihydrate
Authors: Beyer Günter 
Published: August 2002

AbstractFlame retardant nanocomposites are synthesized by melt‐blending ethylene–vinyl acetate copolymers (EVA) with modified layered silicates (montmorillonites). Thermogravimetric analysis performed under different atmospheres (nitrogen and air) demonstrated a clear increase in the thermal stability of the layered silicate‐based nanocomposites. The use of the cone calorimeter to investigate the fire properties of the materials indicated that the nanocomposites caused a large decrease in heat release. The char‐formation is the main factor important for improvement and its function is outlined. Further improvements of the flame retardancy by combinations of nanofillers and traditional FR‐additives on the basis of metal hydroxides were also studied. Copyright © 2002 John Wiley & Sons, Ltd.
Antibacterial activity of volatile secondary metabolites from Caribbean soft corals of the genus Gorgonia
Authors: Roussis Vassilios , Chinou Ioanna B. , Tsitsimpikou Christina , Vagias Constantinos , Petrakis Panos V. 
Published: August 2002

AbstractThe volatile secondary metabolites of Caribbean corals from three species of the genus Gorgonia were studied. The main constituents of the gorgonian species G. ventalina, G. flabelum and G. mariae were identified and 12 metabolites were isolated and identified. The in vitro antibacterial activity of the volatile constituents was also studied against six Gram‐positive or ‐negative bacteria exhibiting a wide spectrum of antibacterial activities. Furanotriene, dihydro‐α‐santalen‐12‐one and E‐nerolidol showed the most interesting antibacterial action. Copyright © 2001 John Wiley & Sons, Ltd.
Volatile constituents of Vietnamese pummelo, orange, tangerine and lime peel oils
Authors: Minh Tu N. T. , Thanh L. X. , Une A. , Ukeda H. , Sawamura M. 
Published: August 2002

AbstractThe compositions of Vietnamese pummelo (Citrus grandis Osbeck), orange (C. sinensis Osbeck), tangerine (C. reticulata Blanco var. tangerine) and lime (C. limonia Osbeck) peel oil samples have been investigated by GC and GC–MS. The essential oils were extracted by the cold‐pressing method. Hydrocarbons, followed by aldehydes and alcohols, were the most abundant compounds in all four kinds of samples. Their percentages, respectively, were >98.7%, >97.6%, >98.6% and >95.4% in hydrocarbons; >0.3%, 0.4%, >0.3% and 1.1% in total aldehydes; 0.2%, 0.5%, 0.4% and 0.7% in alcohols. In Vietnamese pummelo oil, γ‐terpinene was not detected, while terpinolene was detected in small amounts and nootkatone only at a level of <0.05%. Orange oil composition was comparable to that of other sweet orange oils. δ‐3‐Carene was detected at a level of 0.1%. Tangerine oil is easily distinguished from other citrus oils by its content of various aliphatic aldehydes. Lime oil presented a very different composition from the other oils studied. Its limonene content was substantially lower than that of pummelo, orange and tangerine oils, whereas γ‐terpinene, β‐pinene and α‐pinene occurred in higher proportions, moreover, the sesquiterpene hydrocarbon fraction of this oil is qualitatively more complex and quantitatively more abundant than in the other oils. Copyright © 2002 John Wiley & Sons, Ltd.
Numerical simulation of mold filling in injection molding using a three‐dimensional finite volume approach
Authors: Chang Rong‐yeu , Yang Wen‐hsien 
Published: August 2002

AbstractThis work presents an implicit finite volume approach to simulate the three‐dimensional mold filling problems encountered during the injection molding. The described numerical model deals with the three‐dimensional isothermal flow of incompressible, high‐viscous Newtonian fluids with moving interfaces. The collocated finite volume method and the SIMPLE segregated algorithm are used to discretize and solve the Navier–Stokes equation. In addition, a bounded compressive high‐resolution differencing scheme is adopted to solve the advection equation to capture the interface on a Eulerian framework. This approach effectively solves the flow field in terms of CPU time and memory storage as well as the complicated three‐dimensional melt front topology. Several two‐ and three‐dimensional examples are presented to validate the presented approach and illustrate its capabilities. This method can more accurately predict the critical three‐dimensional phenomena encountered during mold filling than the existing Hele–Shaw analysis model. The presented numerical approach has been proven to be a highly effective and flexible tool for simulating mold filling problems. Copyright © 2001 John Wiley & Sons, Ltd.
High‐order filtering for control volume flow simulation
Authors: De Stefano G. , Denaro F. M. , Riccardi G. 
Published: August 2002

AbstractA general methodology is presented in order to obtain a hierarchy of high‐order filter functions, starting from the standard top‐hat filter, naturally linked to control volumes flow simulations. The goal is to have a new filtered variable better represented in its high resolved wavenumber components by using a suitable deconvolution. The proposed formulation is applied to the integral momentum equation, that is the evolution equation for the top‐hat filtered variable, by performing a spatial reconstruction based on the approximate inversion of the averaging operator. A theoretical analysis for the Burgers' model equation is presented, demonstrating that the local de‐averaging is an effective tool to obtain a higher‐order accuracy. It is also shown that the subgrid‐scale term, to be modeled in the deconvolved balance equation, has a smaller absolute importance in the resolved wavenumber range for increasing deconvolution order. A numerical analysis of the procedure is presented, based on high‐order upwind and central fluxes reconstruction, leading to congruent control volume schemes. Finally, the features of the present high‐order conservative formulation are tested in the numerical simulation of a sample turbulent flow: the flow behind a backward‐facing step. Copyright © 2001 John Wiley & Sons, Ltd.
Efficient computation of natural convection in a concentric annulus between an outer square cylinder and an inner circular cylinder
Authors: Shu C. , Zhu Y. D. 
Published: August 2002

AbstractIn this work, the natural convection in a concentric annulus between a cold outer square cylinder and a heated inner circular cylinder is simulated using the differential quadrature (DQ) method. The vorticity‐stream function formulation is used as the governing equation, and the coordinate transformation technique is introduced in the DQ computation. It is shown in this paper that the outer square boundary can be approximated by a super elliptic function. As a result, the coordinate transformation from the physical domain to the computational domain is set up by an analytical expression, and all the geometrical parameters can be computed exactly. Numerical results for Rayleigh numbers range from 104 to 106 and aspect ratios between 1.67 and 5.0 are presented, which are in a good agreement with available data in the literature. It is found that both the aspect ratio and the Rayleigh number are critical to the patterns of flow and thermal fields. The present study suggests that a critical aspect ratio may exist at high Rayleigh number to distinguish the flow and thermal patterns. Copyright © 2002 John Wiley & Sons, Ltd.
Numerical simulation of laminar flow and heat transfer over banks of staggered cylinders
Authors: Roychowdhury D. Ghosh , Das Sarit Kumar , Sundararajan T. 
Published: August 2002

AbstractA study is conducted to investigate forced convective flow and heat transfer over a bank of staggered cylinders. Using a novel numerical formulation based on a non‐orthogonal collocated grid in a physical plane, the effects of Reynolds number and cylinder spacing on the flow and heat transfer behaviour are systematically studied. It is observed that both the Reynolds number and cylinder spacing influence the recirculatory vortex formation and growth in the region between the cylinders; in turn, the rates of heat transfer between the fluid and the staggered cylinders are affected. As the cylinder spacing decreases, the size and length of eddies reduce. For sufficiently small spacings, eddy formation is completely suppressed even at high Reynolds number. Pressure drop and Nusselt number predictions based on numerical study are in excellent agreement with available correlations. The study provides useful insight on the detailed flow and heat transfer phenomena for the case of a bank of staggered cylinders. Copyright © 2002 John Wiley & Sons, Ltd.
The Demand for Hedging with Futures and Options
Authors: Frechette Darren L. 
Published: August 2002

AbstractThe optimal hedging portfolio is shown to include both futures and options under a variety of circumstances when the marginal cost of hedging is nonzero. Futures and options are treated as substitute goods, and the properties of the resulting hedging demand system are explained. The overall optimal hedge ratio is shown to increase when the marginal cost of trading options is reduced. The overall optimal hedge ratio is shown to decrease when the marginal cost of trading futures is decreased. One implication is that hedging demand can be stimulated by a reduction in the perceived cost of trading options through the education of hedgers about options and the initiation of programs such as the Dairy Options Pilot Program. The demand approach is applied to estimate optimal hedge ratios for dairy producers hedging corn inputs in five regions of Pennsylvania. © 2001 John Wiley & Sons, Inc. Jrl Fut Mark 21:693–712, 2001
Clustering and psychological barriers: the importance of numbers
Authors: Mitchell Jason 
Published: August 2002

AbstractThe contemporary press frequently makes mention of, and identifies significance with, specific numerical values in financial markets. This focus has been suggested to result in clustering. Furthermore, these symbolic numbers are often referred to as psychological barriers. These effects are identified as a widespread phenomenon permeating into the economic decision making and financial market environments. This article outlines various arguments and rationale from the cultural, economic, and behavioral literature why clustering and other effects such as psychological barriers may be expected in financial markets. Evidence across a variety of literatures suggests that financial market clustering derives from a variety of sources. There is evidence from a cultural and conventional basis to suggest that number preference exists and that there is a natural tendency to round that derives from the development of the modern decimal system. The literature also provides valid behavioral and economic reasons as to why these effects may occur. However, no evidence is found to support the notion that clustering or barriers in financial markets would occur as a result of a natural order or as a product of the number progression or simply from the numbers themselves. © 2001 John Wiley & Sons, Inc. Jrl Fut Mark 21:395–428, 2001
Novel ERBB4 juxtamembrane splice variants are frequently expressed in childhood medulloblastoma
Authors: Gilbertson Richard , Hernan Roberto , Pietsch Torsten , Pinto Lais , Scotting Paul , Allibone Richard , Ellison David , Perry Robert , Pearson Andrew , Lunec John 
Published: August 2002

AbstractWe recently reported a significant relationship between tumor cell expression of the ERBB4 receptor, the most recently described member of the epidermal growth factor receptor family, and aggressive tumor phenotype in childhood medulloblastoma. Two alternative juxtamembrane (JM) isoforms of the ERBB4 receptor have been described. Termed JMa and JMb, these variants possess different receptor processing and ligand‐binding characteristics. In the current study, we employed an RT‐PCR and sequencing strategy to determine the pattern of ERBB4 JM isoform expression in a large (n = 78) series of pediatric medulloblastomas. JMa and JMb transcript expression was detected in 53% and 28% of tumor samples, respectively. In addition, two novel ERBB4 JM isoforms, which we have termed JMc and JMd, were isolated from 10% and 36% of tumors, respectively. Sequence analysis revealed the JMc transcript to contain a deletion of the entire JM region. In contrast, JMd includes an extended coding region, retaining both the JMa and JMb sequences. Neither of these novel isoforms was detected in normal human adult cerebellum, but expression of JMd was observed in developing fetal cerebellum, suggesting that this later isoform may represent an ERBB4 transcript restricted to primitive neuroectoderm‐derived tissue. To confirm that the four ERBB4 JM isoforms arise by alternative RNA splicing, we sequenced the intron‐exon junctions of the human ERBB4 gene within the JM region. This demonstrated the four ERBB4 JM variants to be encoded by two short exons containing the JMb and JMa sequences positioned in the order 5′ to 3′ and separated by a 121 bp intron. © 2001 Wiley‐Liss, Inc.
An ins(X;11)(q24;q23) fuses the MLL and the Septin 6/KIAA0128 gene in an infant with AML‐M2
Authors: Borkhardt Arndt , Teigler‐Schlegel Andrea , Fuchs Uta , Keller Claudia , König Margit , Harbott Jochen , Haas Oskar A. 
Published: August 2002

AbstractThe MLL (HRX, ALL‐1 HTRX) gene at chromosome band 11q23 frequently is rearranged in acute lymphoblastic and myeloblastic leukemia. To date, more than 40 different 11q23 abnormalities have been described on the cytogenetic level, and at least 25 of the respective fusion partner genes are cloned. The vast majority of the respective reciprocal translocations generate a chimeric 5′‐MLL/partner‐3′ gene on the derivative 11q23. In this work, we report a unique ins(X;11)(q24;q23) in an infant with acute myeloid leukemia (AML‐M2) that fuses the human KIAA0128 gene at Xq24 with MLL. In contrast to the typical reciprocal MLL translocations, however, we provide evidence that the 5′‐MLL/KIAA0128‐3′ fusion resides on Xq24 rather than on 11q23. The KIAA0128 gene encodes the human Septin 6 protein, which contains an ATP‐GTP binding motif and three nuclear targeting sequences in its carboxy terminus. The maintenance of the reading frame of the 5′‐MLL/KIAA0128‐3′ mRNA fusion allows for the formation of a novel chimeric protein. Septin 6 is the third member of the Septins that is fused to the MLL protein; the other two are hCDCrel at 22q11 and MSF at 17q25. © 2001 Wiley‐Liss, Inc.
SNRPN methylation patterns in germ cell tumors as a reflection of primordial germ cell development
Authors: Bussey Kimberly J. , Lawce Helen J. , Himoe Eleanor , Shu Xiao Ou , Heerema Nyla A. , Perlman Elizabeth J. , Olson Susan B. , Magenis R. Ellen 
Published: August 2002

AbstractStudies examining altered imprinted gene expression in cancer compare the observed expression pattern to the normal expression pattern for a given tissue of origin, usually the somatic expression pattern for the imprinted gene. Germ cell tumors (GCTs), however, require a developmental stage‐dependent comparison. To explore using methylation as an indicator of germ cell development, we determined the pattern of methylation at the 5′ untranslated region of SNRPN in 89 GCTs from both children and adults. Fifty‐one of 84 tumors (60.7%) (12/30 (40%) of cultured pediatric GCTs, 23/36 (63.9%) of frozen adult GCTs, and 16/23 (69.5%) of frozen pediatric GCTs, with five samples having results from both cultured and uncultured material) demonstrated a nonsomatic methylation pattern after dual digestion with XbaI, NotI, and Southern blot analysis. In contrast, only 2 of 18 (11%) control samples (16 non‐GCTs and 2 normal ovaries) exhibited a nonsomatic pattern. In both cases, the result was shown to be due to copy number differences between maternal and paternal homologs, unlike the GCTs in which there was no evidence of an uneven homolog number. A comparison of the data for only the gonadal GCTs and the control data showed a highly significant difference in the proportion of tumors with methylation alterations at this locus (P = 0.0000539). Since there is no published evidence of the involvement of SNRPN methylation changes in the development of malignancy, the data suggest that the methylation pattern of SNRPN in GCTs reflects that of the primordial germ cell giving rise to the tumor. © 2001 Wiley‐Liss, Inc.
Biomantle formation and artifact translocation in upland sandy soils: An example from the Holly Springs National Forest, north‐central Mississippi, U.S.A.
Authors: Peacock Evan , Fant David W. 
Published: August 2002

AbstractTest excavations at prehistoric site 22MR539 in the North Central Hills uplands of Mississippi have provided evidence of the effects of bioturbation on artifacts within the soil. Artifact distribution and size data are compared to soil particle size and organic content to determine the soil developmental pathway. Progressive soil formation factors have formed a biomantle over a currently forming artifact stone line, while regressive factors have moved artifacts to a depth of more than 50 cm below surface over approximately 2000 years. The single‐component, short‐term nature of 22MR539 and many similar sites recorded in the area provide an ideal situation to further explore biological and mechanical factors in site formation in an upland setting. © 2002 John Wiley & Sons, Inc.