bluuebunny/crossref_metadata_2025_split huggingface dataset:
Higher Order Difference Schemes for the First and Third Boundary Value Problem to \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{1}{r}\;\frac{{\rm d}}{{{\rm d}r}}\left({r\frac{{{\rm d}u}}{{{\rm d}r}}} \right)\; + \;f\left( r\right) \; = \;0 $\end{document}
Authors: Stoyan Gisbert 
Published: May 2007

AbstractFirstly, the exact difference scheme is constructed for the problem posed in [0, R1]. Then, this is used to get a third order difference scheme. For the problem considered in [R0, R1], R0 > 0, the accuracy of the scheme is also O(h3) (without assumptions on R0/h). In the case of 0 < R0 = O(1) and the first boundary value problem, accuracy increases to be O(h4). The paper contains an ALGOL program implementing the described scheme and some numerical results.
Lineare konstitutive Gleichungen der viskoelastischen Cosseratfläche
Authors: Rothert H. 
Published: May 2007

AbstractBei der Untersuchung des physikalischen Verhaltens deformierbarer Werkstoffe hat sich in letzter Zeit das lebhafte Interesse für Stoffe mit wirklichkeitsnahem rheologischem Verhalten in einer Vielzahl von Veröffentlichungen dokumentiert. Hier wird erstmals der Versuch unternommen, konstitutive Gleichungen für anisotrope zweidimensionale Kontinua aus linear viskoelastischem Werkstoff im Rahmen einer nicht‐isothermen Cosserattheorie anzugeben. In einer geschlossenen Ableitungskette wird ein Weg aufgezeigt, der von einer geeigneten Repräsentation der freien Helmholtzschen Energie und des Wärmeflusses unter Berücksichtigung der Hauptsätze der Thermodynamik bis zu numerisch auswertbaren Gleichungssystemen reicht.
Representations and Fundamental Singular Solutions in Micropolar Fluid
Authors: Ramkissoon H. , Majumdar S. R. 
Published: May 2007

AbstractWith the aid of elementary matrix operations, simple representations are obtained for the equations governing the slow, steady motion of micropolar fluids. These representations lead to the construction of the fundamental solutions for a concentrated force as well as a concentrated couple in both a planar domain and three dimensional space. The basic solutions and the reciprocity theorem yield integral representations for the velocity and rotation vectors.
Theory of Flat Slabs with Edges Free or Supported by Walls
Authors: Ono K. 
Published: May 2007

AbstractAssuming that uniformly distributed load or horizontal forces are applied, the bending of a long plate or flat slab which is supported by several or many rows of equidistant columns is studied. As for the boundary conditions the following two cases are considered. (1) The opposite two edges are free, (2) The opposite two edges are supported and clamped to the walls. The capitals of the columns are assumed to be clamped to the slab and the resisting couples applied to the slab from the columns are also considered.
Numerical Solutions and Mathematical Theorems for Divergent, Compressible Plasma Flows
Authors: Liron N. , Wilhelm H. E. 
Published: May 2007

AbstractThe boundary‐value problem for the ordinary nonlinear differential equation of second order, resulting from the self‐similar transformation of the partial differential equations for a polytropic, compressible plasma flow in a diffuser with azimuthal magnetic field, is integrated rigorously by numerical methods. Typical velocity profiles of symmetrical outflows are given for various Reynolds, Hartmann, and polytropic numbers. Mathematical theorems are derived which prove that the selfsimilar transformation of the plasma fields of the form F(r, θ) = (r)G(θ) cannot represent pure inflows, mixed in‐ and outflows and asymmetrical flows, i.e., is applicable exclusively to symmetrical outflows without backflow regions (within the polytropic approximation).
Über die Stabilisierung von freien leitenden Grenzschichten im transversalen Magnetfeld
Authors: Plaschko P. 
Published: May 2007

AbstractEs wurde eine theoretische Untersuchung der MHD‐Stabilität von freien Grenzschichten im transversalen Magnetfeld durchgeführt. Die linearisierten MHD‐Stabilitätsgleichungen werden im Grenzfalle sehr kleiner magnetischer Reynolds‐zahlen und unter Beschränkung auf ebene Störungen aufgestellt und aus ihnen eine neue Art von Übergangsbedingung, die die Stetigkeit eines aus hydrodynamischen und magnetischen Zusatzdruck gebildeten Druckes fordert, gewonnen. Für transversale Magnetfelder ist die Verwendung beliebiger Geschwindigkeitsprofile nur für sehr kleine Wechselwirkungsparameter gestattet. Für größere Werte des Wechselwirkungsparameters wird ein mit dem nichtmagnetischen Grenzfall konsistentes Geschwindigkeitsprofil angegeben und die ihm entsprechende Eigenwertgleichung einer Isolator‐Leiter‐Sprung Schicht aufgestellt. Es wird gezeigt, daß sich die Instabilitäten im Pumpen‐ bzw. Generatorbetrieb besser stabilisieren lassen als im Leerlaufbetrieb, dessen Verhalten dem in einem longitudinalen Feld entspricht.
Ein Beulproblem für die eingespannte Kreisplatte mit Unterstützungen
Authors: Miersemann E. 
Published: May 2007

AbstractDas unten beschriebene Beulproblem für die eingespannte Kreisplatte führt auf eine Variationsungleichung mit einem Eigenwertparameter. Unter gewissen Voraussetzungen für die Unterstützungen existieren höhere Eigenwerte dieser Ungleichung.
Comments on an Exact Solution of the FALKNER‐SKAN Equation
Authors: Moulden T. H. 
Published: May 2007

AbstractThis note discusses the entire solution space for the Falkner‐Skan equation when the pressure gradient parameter takes the value β = ‐1. In this sense, the work is a direct extension of the results of Yang and Chien [11]. Various solution branches resulting from the non‐uniqueness of the boundary value problem are examined in detail. Wake type solutions of the equation are not discussed.
The preparation and purification of monoglycerides. II. Direct esterification of fatty acids with glycerol
Authors: Choudhury R. Basu Roy 
Published: May 2007

AbstractStudies have been made on the direct esterification reaction with various saturated and unsaturated fatty acids using more than theoretical concentration of glycerol (for maximum monoglyceride production) at 180C reaction temperature and in presence and absence of alkaline catalyst. The results show that the maximum monoglyceride formed is in the range of 55舑60% of the fatty product at equilibrium stage of the reaction. The alkaline catalyst substantially increases the initial rate of reaction without appreciably lowering the time required for reaching the equilibrium concentration of monoglyceride in the resulting reaction mixture. Catalyst helps in depressing diglyceride formation.
Limitations of the periodate oxidation method for the determination of monoglycerides in fats and oils
Authors: Kummerow F. A. , Daubert B. F. 
Published: May 2007

SummaryPeriodate values were determined on a variety of fats and oils before and after saponification by the periodic acid oxidation method of Handschumaker and Linteris.The values obtained indicate that the method is not specific for monoglycerides in natural fats and oils. Therefore previous reports of the natural occurrence of monoglycerides in fats and oils, where the periodate method has been used, may be open to question.
Polyphosphates as synergistic antioxidants
Authors: Watts Betty M. 
Published: May 2007

Summary and ConclusionsThe antioxidant activities of a number of synergists were measured in aqueous fat systems at several pH values. A group of polyphosphates not previously investigated was most promising of the synergists tried. Orthophosphates were ineffective but antioxidant activity increased from pyrophosphate through tri and “heptaphosphate” and finally to the most active “hexametaphosphate” and Maddrell's salt. Citrate compared with triphosphate and pyrophosphate in antioxidant activity; all other synergists tried were less effective than pyrophosphate.Relatively large molar concentrations of orthophosphates interfered markedly with the antioxidant activity of citrate and the higher polyphosphates.The polyphosphates also inhibited rancidity in the presence of added copper and iron but did not eliminate the catalytic effect of the metals.Antioxidant activity of the phosphates in dry fats did not parallel their activity in aqueous fat systems.Properties of polyphosphates which might affect their use as antioxidants in foods are discussed.
Germination and free fatty acids in seed stock lots of cottonseed
Authors: Hoffpauir Carroll L. , Poe Sam E. , Wiles L. U. , Hicks Martha 
Published: May 2007

SummaryThe relationship of the free fatty acid content in the oil to the percentage germination for 254 samples of cottonseed of different varieties indicates that the free fatty acid content may be used as a practical screening index for use in selecting lots of cottonseed to be reserved for seeding purposes and subsequent testing for germination. The percentage germination decreases in general with increasing free fatty acid content. The mathematical probability that a given lot of seed will exceed a specified minimum germination value decreases markedly as the free fatty acid content of the oil increases. Insofar as practical, it is suggested that cottonseed reserved for seeding have a low free fatty acid content, less than 0.75% in the oil if at all possible.
The raw linseed oil acetone foots test. I. A centrifuge tube and method for rapid determination
Authors: Freyer Egbert , Shelburne Victor B. 
Published: May 2007

SummaryA rapid method, requiring less than one hour to apply, has been developed for determining the acetone foots content of linseed oils using centrifugal force to compact the foots layer instead of the force of gravity. Application of the method requires the use of a centrifuge tube of novel design. Conditions known to affect the results obtained by the A.S.T.M. gravity test have been investigated as they apply to the centrifuge test and found to have little or no effect on the results of the latter test. Correlation of the percentage of centrifugal foots under stated conditions with percentage of foots by the gravity method has been determined for both the heated and chilled tests. Under the conditions chosen for the centrifugal test the magnitude of the heated test result is about the same as the processing shrink sustained when these foots are removed in practice. The reproducibility of the method, based on this work, is equal to or better than the gravity test now in use for trading linseed oil.
Density‐composition data for cottonseed oil‐solvent mixtures
Authors: Magne Frank C. , Hughes Edwin J. , Skau Evald L. 
Published: May 2007

SummaryComplete density‐composition‐temperature data have been reported for binary systems of a refined cottonseed oil with methyl pentane, diethyl ether, trichloro‐ethylene, and tetrachloroethylene from the point of incipient phase separation to within 10° to 15°C. of the boiling point of the solvent. These data can be used to calculate the density knowing the composition and temperature or, conversely, the composition knowing the density and temperature.An equation has been derived which makes it possible to adjust these data so that they apply with reasonable accuracy to other refined and crude cottonseed oils and even to soybean or peanut oil systems with the same solvents.
The utilization of the seeds of the wild perennial gourds
Authors: Bolley Don S. , McCormack Ralph H. , Curtis Laurence C. 
Published: May 2007

ConclusionsThe experiments described above indicate that the seeds from three species of wild perennial gourds,Cucurbita foetidissima, C. digitata, andC. palmata, have a potential value. Drying oils, high protein flour, and chemically purified protein may easily be obtained from the seeds by standard procedures used for other oil seeds. While theC. digitata andC. palmata oils are different than other natural drying oils, their evaluation would place them in the class with linseed oil for general use in protective coatings.C. foetidissima lacks the conjugated triene component so is a somewhat “softer” drying oil, more smilar to soybean. The wild gourds should continue to receive serious consideration as an oil seed crop, particularly for arid and semi‐arid land.
Pregnancy‐induced hypertension and infant mortality in triplets
Authors: Chen X.K. , Wen S.W. , Smith G.N. , Yang Q. , Walker M.C. 
Published: May 2007

AbstractObjective: To assess the effects of pregnancy‐induced hypertension on infant mortality in triplets stratified by gestational age at birth. Methods: A retrospective cohort study was conducted using the linked 1995–2000 US birth/infant death database. Generalized estimating equations were used to evaluate the observed association. Results: Pregnancy‐induced hypertension was associated with lesser neonatal mortality (odds ration [OR]: 0.34, 95% CI: 0.21, 0.54), postneonatal mortality (OR: 0.54, 95% CI: 0.30, 0.99) and infant mortality (OR, 0.37, 95% CI: 0.25, 0.55) in triplets. It was also associated with a decreased risk of neonatal death (OR, 0.38; 95% CI, 0.21–0.67), postneonatal death (OR, 0.45; 95% CI, 0.21–0.97), and infant death (OR, 0.39; 95% CI, 0.24–0.64) in early preterm triplets, whereas the association was not significant in late preterm or in full‐term triplets. Conclusion: Pregnancy‐induced hypertension is associated with a decreased risk of infant mortality in triplets. This effect varies with gestational age at birth.
Psyttalia ponerophaga (Hymenoptera: Braconidae) as a potential biological control agent of olive fruit fly Bactrocera oleae (Diptera: Tephritidae) in California
Authors: Sime K.R. , Daane K.M. , Kirk A. , Andrews J.W. , Johnson M.W. , Messing R.H. 
Published: May 2007

AbstractThe olive fruit fly, Bactrocera oleae (Rossi), is a newly invasive, significant threat to California's olive industry. As part of a classical biological control programme, Psyttalia ponerophaga (Silvestri) was imported to California from Pakistan and evaluated in quarantine. Biological parameters that would improve rearing and field-release protocols and permit comparisons to other olive fruit fly biological control agents were measured. Potential barriers to the successful establishment of P. ponerophaga, including the geographic origins of parasitoid and pest populations and constraints imposed by fruit size, were also evaluated as part of this investigation. Under insectary conditions, all larval stages except neonates were acceptable hosts. Provided a choice of host ages, the parasitoids' host-searching and oviposition preferences were a positive function of host age, with most offspring reared from hosts attacked as third instars. Immature developmental time was a negative function of tested temperatures, ranging from 25.5 to 12.4 days at 22 and 30°C, respectively. Evaluation of adult longevity, at constant temperatures ranging from 15 to 34°C, showed that P. ponerophaga had a broad tolerance of temperature, living from 3 to 34 days at 34 and 15°C, respectively. Lifetime fecundity was 18.7±2.8 adult offspring per female, with most eggs deposited within 12 days after adult eclosion. Olive size affected parasitoid performance, with lower parasitism levels on hosts feeding in larger olives. The implications of these findings are discussed with respect to field manipulation and selection of parasitoid species for olive fruit fly biological control in California and worldwide.
Genetic structure and molecular variability ofSpodoptera frugiperda(Lepidoptera: Noctuidae) collected in maize and cotton fields in Brazil
Authors: Martinelli S. , Clark P.L. , Zucchi M.I. , Silva-Filho M.C. , Foster J.E. , Omoto C. 
Published: May 2007

AbstractThe purpose of this research was to evaluate the genetic similarity and structure of the fall armyworm,Spodoptera frugiperda(J.E. Smith), populations associated with maize and cotton crops in Brazil using amplified fragment length polymorphisms. Mean genetic similarity among populations was 0.45. The unweighted pair group method with arithmetic mean analysis dendrograms did not separate populations ofS. frugiperdainto clusters related to the host plant in which the insects were collected. No genetic variation was observed among maize and cotton populations ofS. frugiperda, suggesting that the same populations are injuring both crops in Brazil. This research validates the need for stewardship of crop-protection methods for managingS. frugiperdato reduce the incidence of pesticide resistance, due to the spatial and temporal overlapping of maize and cotton crops in some regions in Brazil.
Genetic differentiation ofCulex pipiens(Diptera: Culicidae) in China
Authors: Cui F. , Qiao C.-L. , Shen B.-C. , Marquine M. , Weill M. , Raymond M. 
Published: May 2007

AbstractThe population genetic structures ofCulex pipiensLinnaeus were evaluated in China over a 2000 km transect that encompasses the two subspecies,C. p. pallensandC. p. quinquefasciatus. Four polymorphic allozyme loci were investigated in 1376 mosquitoes sampled from 20 populations across four provinces. These loci were not statistically dependent with no apparent heterozygote deficit or excess. On a regional scale (intra-province), a low (Fst=0.007–0.016) and significant genetic differentiation was found, with no clear geographical pattern. On a wider scale (inter-province), the genetic differentiation was higher (Fst=0.059), and an isolation by distance emerged. The results are compared with previous population genetic surveys of this mosquito species in different geographic areas over the world. The overall pattern suggests thatCulex pipiensrequires considerable distance (500–1000 km) to show isolation by distance, irrespective of the subspecies (C. p. pipiens,C. p. quinquefasciatusandC. p. pallens) or the geographic location.
Identification of priority areas for plant conservation in Madagascar using Red List criteria: rare and threatened Pandanaceae indicate sites in need of protection
Authors: Callmander Martin W. , Schatz George E. , Lowry II Porter P. , Laivao Michel O. , Raharimampionona Jeannie , Andriambololonera Sylvie , Raminosoa Tantely , Consiglio Trisha K. 
Published: May 2007

AbstractA major problem in establishing effective protocols for conserving Madagascar's biodiversity is the lack of reliable information for the identification of priority sites in need of protection. Analyses of field data and information from herbarium collections for members of the plant family Pandanaceae (85 spp. of Pandanus; 6 spp. of Martellidendron) showed how risk of extinction assessments can inform conservation planning. Application of IUCN Red List categories and criteria showed that 91% of the species are threatened. Mapping occurrence revealed centres of richness and rarity as well as gaps in Madagascar's existing protected area network. Protection of 10 additional sites would be required to encompass the 19 species currently lacking representation in the reserve network, within which east coast littoral forests are particularly under represented and important. The effect of scale on assessments of risk of extinction was explored by applying different grid cell sizes to estimate area of occupancy. Using a grid cell size within the range suggested by IUCN overestimates threatened status if based solely upon specimen data. For poorly inventoried countries such as Madagascar measures of range size based on such data should be complemented with field observations to determine population size, sensitivity to disturbance, and specific threats to habitat and therefore potential population decline. The analysis of such data can make an important contribution to the conservation planning process by identifying threatened species and revealing the highest priority sites for their conservation.
Priority setting for conservation in south-west Cameroon based on large mammal surveys
Authors: Forboseh P. F. , Sunderland T. C. H. , Eno-Nku M. 
Published: May 2007

AbstractThe forests of the Cameroon-Nigeria transboundary region have been highlighted as a high conservation priority, yet many of the extant forest remnants remain relatively unknown, particularly with regard to the occurrence of large mammals. Between 2002 and 2004 we surveyed the large mammal fauna of the Mone and Ejagham Forest Reserves and the Upper Banyang, Nkwende Hills and Etinde forests of south-west Cameroon. Our objective was to document the extant large mammal species as an important step in the review of government priorities to identify key sites within the region for conservation and management. We reviewed the available literature on mammal distribution and then surveyed the forests for mammal and human signs. Despite a growing illegal commercial trade in wildlife, particularly for bushmeat, many sites retain populations of one or more threatened and locally rare large mammal species of significant conservation importance. Moreover, the sites collectively complement each other in terms of their representation of the threatened large mammal fauna. An emphasis on the enforcement of wildlife legislation and minimizing logging impact are of primary importance for the conservation of large mammals in these and other forest remnants in south-west Cameroon. In addition, at some sites, there already exists community interest in active wildlife management.
Not rare, but threatened: the endemic Madagascar flying fox Pteropus rufus in a fragmented landscape
Authors: Jenkins Richard K. B. , Racey Paul A. , Andriafidison Daudet , Razafindrakoto Noromampiandra , Razafimahatratra Emilienne , Rabearivelo Andriamanana , Ratsimandresy Zo , Andrianandrasana Rabe H. , Razafimanahaka H. Julie 
Published: May 2007

AbstractThe endemic Madagascar flying fox Pteropus
rufus is threatened by habitat loss at roost sites and hunting for
bushmeat. There is no conservation plan for this species, even though it is
categorized on the IUCN Red List as Vulnerable and plays an important role as a
seed disperser. In the Mangoro valley of central eastern Madagascar we monitored
roost occupancy and abundance of P. rufus on
15 occasions at six sites over a 12-month period and conducted a detailed
assessment of eight roosts during July 2004. There was considerable monthly
variation in bat abundance and only two sites contained bats during every visit.
Three sites were occupied only between September and March and may act as
maternity or nursery roosts. Evidence of hunting was found at three roosts, and
fire and forest clearance are ubiquitous threats. Two roosts were in Eucalyptus plantations and six were in small (2.2 -
28.7 ha) isolated fragments of degraded, mid elevation dense humid forest. All
roosts were outside protected areas but were within 20 km of relatively intact
forest. Faecal analysis revealed a diet of native forest tree species,
cultivated fruits and Eucalyptus flowers.
P. rufus in the Mangoro valley, and
elsewhere in Madagascar, appears to survive in human-impacted environments by
the inclusion of exotic plants in its diet and the ability to move between
roosts. We provide conservation recommendations for P.
rufus at both local and national levels.
The importance of north-west Madagascar for marine turtle conservation
Authors: Metcalf Jessica , Hampson Katie , Andriamizava Alain , Andrianirina Rivo , Ramiarisoa Claudine , Sondotra Henriot , Cairnes Tom , Gray Anna 
Published: May 2007

AbstractThe coast of north-west Madagascar is an important nesting and feeding ground for marine turtles, but little is known about populations in this area. From July to December 2000 we documented nesting activity of, and investigated threats to, green Chelonia mydas and hawksbill Eretmochelys imbricata turtles at three sites along this coast: Nosy Iranja, the Radama Islands, and the Nosy Hara archipelago. Levels of nesting activity varied between sites, with green and hawksbill turtle nesting concentrated in different areas. The principal threats identified were opportunistic exploitation of nesting females and incidental capture in fishing nets. Commercial importance of marine turtles was negligible, suggesting conservation measures such as targeted environmental education could have beneficial impacts on these populations. Evidence for high levels of nesting activity reported here indicate that education efforts in these areas should be a conservation priority.