bluuebunny/crossref_metadata_2025_split huggingface dataset:
Near-contact motion of surfactant-covered spherical drops
Authors: CRISTINI VITTORIO , BŁAWZDZIEWICZ J. , LOEWENBERG MICHAEL 
Published: July 2002

A lubrication analysis is presented for the near-contact axisymmetric
motion of
spherical drops covered with an insoluble non-diffusing surfactant. Detailed
results
are presented for the surfactant distribution, the interfacial velocity,
and the gap width
between the drop surfaces. The effect of surfactant is characterized by
a dimensionless
force parameter: the external force normalized by Marangoni stresses. Critical
values
of the force parameter have been established for drop coalescence and separation.

Surfactant-covered drops are stable to rapid coalescence for external forces
less than
4πkTac0, where c0 is the
surfactant concentration at the edge of the near-contact
region and a is the reduced drop radius.For subcritical forces, the behaviour of surfactant-covered drops is
described by two
time scales: a fast time scale characteristic of near-contact motion between
drops with
clean interfaces and a slow time scale associated with rigid particles.
The surfactant
distribution evolves on the short time scale until Marangoni stresses approximately

balance the external force. Supercritical values of the external force
cannot be balanced;
coalescence and separation occur on the fast time scale. The coalescence
time
normalized by the result for drops with clean interfaces is independent
of the viscosity
ratio and initial gap width.Under subcritical force conditions, a universal long-time behaviour
is attained on
the slow time scale. At long times, the surfactant distribution scales
with the
near-contact region and the surface velocity is directed inward which impedes
the drop
approach and accelerates their separation compared to rigid particles.
For drops
pressed together with a sufficiently large subcritical force, a shrinking
surfactant-free
clean spot forms.Surfactant-covered drops exhibit an elastic response to unsteady external
forces
because of energy stored in the surfactant distribution.
Three-dimensional analysis of the steady-state
shape and small-amplitude oscillation of a
bubble in uniform and non-uniform electric fields
Authors: LEE S. M. , KANG I. S. 
Published: July 2002

A three-dimensional analysis is performed to investigate
the effects of an electric field
on the steady deformation and small-amplitude oscillation of a bubble in
dielectric
liquid. To deal with a general class of electric fields, an electric field
near the bubble is
approximately represented by the sum of a uniform field and a linear field.
Analytical
results have been obtained for steady deformation and modification of oscillation

frequency by using the domain perturbation method with the angular momentum

operator approach.It has been found that, to the first order, the steady shape of a bubble
in an
arbitrary electric field can be represented by a linear combination of
a finite number
of spherical harmonics Yml,

where 0[les ]l[les ]4 and [mid ]m[mid ][les ]l. For the oscillation
about
the deformed steady shape, the overall frequency modification from the
value of
free oscillation about a spherical shape is obtained by considering two
contributions
separately: (i) that due to the deformed steady shape (indirect effect),
and (ii) that
due to the direct effect of an electric field. Both the direct and indirect
effects of
an electric field split the (2l+1)-fold degenerate frequency of

Yml modes, in the case

of free oscillation about a spherical shape, into different frequencies
that depend on
m. However, when the average is taken over the
(2l+1) values of m, the frequency
splitting due to the indirect effect via the deformed steady shape preserves
the average
value, while the splitting due to the direct effect of an electric field
does not.The oscillation characteristics of a bubble in a uniform electric field
under the
negligible compressibility assumption are compared with those of a conducting
drop
in a uniform electric field. For axisymmetric oscillation modes, deforming
the steady
shape into a prolate spheroid has the same effect of decreasing the oscillation
frequency
in both the drop and the bubble. However, the electric field has different
effects on
the oscillation about a spherical shape. The oscillation frequency increases
with the
increase of electric field in the case of a bubble, while it decreases
in the case of a drop.
This fundamental difference comes from the fact that the electric field
outside the
bubble exerts a suppressive surface force while the electric field outside
the conducting
drop exerts a pulling force on the surface.
An energy criterion for the linear stability of conservative flows
Authors: DAVIDSON P. A. 
Published: July 2002

We investigate the linear stability of inviscid flows which are subject to a conservative
body force. This includes a broad range of familiar conservative systems, such as
ideal MHD, natural convection, flows driven by electrostatic forces and axisymmetric,
swirling, recirculating flow. We provide a simple, unified, linear stability criterion valid
for any conservative system. In particular, we establish a principle of maximum action
of the formformula herewhere η is the Lagrangian displacement,e is a measure of the disturbance energy,
T and V are the kinetic and potential energies, and L is the Lagrangian. Here d
represents a variation of the type normally associated with Hamilton's principle,
in which the particle trajectories are perturbed in such a way that the time of
flight for each particle remains the same. (In practice this may be achieved by
advecting the streamlines of the base flow in a frozen-in manner.) A simple test
for stability is that e is positive definite and this is achieved if L(η) is a maximum
at equilibrium. This captures many familiar criteria, such as Rayleigh's circulation
criterion, the Rayleigh–Taylor criterion for stratified fluids, Bernstein's principle for
magnetostatics, Frieman & Rotenberg's stability test for ideal MHD equilibria, and
Arnold's variational principle applied to Euler flows and to ideal MHD. There
are three advantages to our test: (i) d2T(η) has a particularly simple quadratic
form so the test is easy to apply; (ii) the test is universal and applies to any
conservative system; and (iii) unlike other energy principles, such as the energy-Casimir method or the Kelvin–Arnold variational principle, there is no need to
identify all of the integral invariants of the flow as a precursor to performing the
stability analysis. We end by looking at the particular case of MHD equilibria. Here
we note that when u and B are co-linear there exists a broad range of stable steady
flows. Moreover, their stability may be assessed by examining the stability of an
equivalent magnetostatic equilibrium. When u and B are non-parallel, however, the
flow invariably violates the energy criterion and so could, but need not, be unstable. In
such cases we identify one mode in which the Lagrangian displacement grows linearly
in time. This is reminiscent of the short-wavelength instability of non-Beltrami Euler
flows.
Multilingualism in Metropolitan London
Authors: Salverda Reinier 
Published: July 2002

A description and discussion of the vast linguistic diversity in the capital of the United Kingdom.LONDON today is an enormous Tower of Babel, where in addition to the common language, English, many other languages are spoken. On Tuesday 13 March 2001, as part of the Lunch Hour Lecture Series at University College London, Professor Reinier Salverda discussed the linguistic diversity of contemporary London, presenting recent data on the other languages spoken there, as well as focussing on the social aspects of this linguistic diversity, in particular issues of language policy and language management. The following is a slightly adapted version of that presentation.
USING A BALANCING PROCEDURE IN MULTICENTER CLINICAL TRIALS
Authors: Rovers Maroeska M. , Straatman Huub , Zielhuis Gerhard A. , Ingels Koen , van der Wilt Gert-Jan 
Published: July 2002

Objective: A basic issue in randomized controlled trials (RCTs) is
whether we can safely assume comparability between groups at baseline with
respect to all potentially important prognostic factors. In other words, did
randomization work sufficiently well? In small trials balanced allocation
procedures are employed, whereas in large-scale trials simple randomization
will do. The question is: When should balancing be considered?Methods: We performed a simulation study in which we varied the
number of categories in the prognostic factors and the number of patients.Results: Simulation showed that, in all instances, a balancing
procedure almost always led to perfect or almost perfect balance, while the
imbalance with simple randomization was larger. To study the effect of
balanced and random allocation on subgroup analyses in our OME trial, we
compared the quotient of the width of the confidence intervals (CI). The
widest CI in random allocation over the 13 hospitals was on average 13% wider
than in balanced allocation.Conclusion: Investigators should always consider balanced
allocation, especially in categories with a low number of patients and when
subgroup analysis over many categories is requested.
Foraging behaviour and food availability of the mahogany gliderPetaurus gracilis(Petauridae: Marsupialia)
Authors: Jackson Stephen M. 
Published: July 2002

AbstractThe mahogany gliderPetaurus gracilisis an endangered species of gliding possum that is only found within a limited distribution in North Queensland, Australia. The foraging behaviour of the mahogany glider was examined to determine how it changes seasonally, by extensive observations of radio‐collared animals over a 2‐year period. A total of 440 h was spent following mahogany gliders, of which 222 h of feeding behaviour was observed. Nectar and pollen were clearly the most important food items, comprising between 50 and 99+ (mean 72.8+) of the observed feeding time when available. Nectar and pollen were consumed almost exclusively from Myrtaceae species withEucalyptus,CorymbiaandMelaleucabeing eaten. Casual observations of a number of faecal samples showed thatc.80+ of pollen grains were digested suggesting that pollen is a major source of protein. Other food items consumed included sap fromAlbizia proceraandAcacia mangium, insects, lerps and honeydew,Acaciaarils and fruit from mistletoes. In using these food items, the mahogany glider relied on complex seasonal cycles of food availability, requiring a high diversity of plants, with each species having distinct periods when it provides food during the year.
Home range and use of space by Chalinolobus tuberculatus, a temperate rainforest bat from New Zealand
Authors: O'Donnell Colin F. J. 
Published: July 2002

AbstractFifty radio‐tagged long‐tailed bats Chalinolobus tuberculatus, belonging to three social groups numbering on average 72–132 bats each, ranged over an area of 11 700 ha in Nothofagus rainforest in the Eglinton Valley, Fiordland, New Zealand, during the austral summers of 1993–96. Bats were followed for 12.7 ± 6.3 (sd) days. Home‐range sizes were among the largest published for Microchiroptera. Median minimum convex polygons (100+ MCPs) for adult males were 1589 ha (max = 5629 ha), 1361 ha for post‐lactating females, and 657 ha for non‐reproductive females. Ranges of lactating females (median = 330 ha), were significantly smaller. Juveniles that were volant for < 2 weeks had the smallest ranges (median = 237 ha) but movements increased significantly after c. 2 weeks to a median of 2006 ha. Movements were frequent and rapid within the range (790 ± 471 sd m/15 min) and average range lengths were 3.3–10.9 km (max = 19 km). Despite their large home ranges, bats concentrated their activity (85+ of fixes) in small core areas that represented a mean of 5.7 ± 1.5+ (sd) of the 100+ MCPs. Ranges of roosting sites were also small, averaging 9.4 ± 1.8+ (sd) of total range size. Bats followed similar movement patterns each night but core areas only overlapped by 43 ± 14+ (sd) from one night to the next. Moderately low levels of overlap of home ranges (31–68+) and of core areas (23–56+) among individuals of the same reproductive class suggest a degree of spatial segregation among bats from the same roosting group. A prediction that C. tuberculatus has large ranges to minimize overlap between foraging bats, reflecting scarcity of food, requires testing. Range sizes were probably underestimates of seasonal, annual, and life‐time range requirements. Nevertheless, large range size and the degree of individual spacing implies that conservation areas designed for bats should be large and that protection of roosting areas alone would not be sufficient to protect bat populations.
The regions of conservation importance for grouse, partridges and pheasants in China
Authors: Chang-qing Ding , Guang-mei Zheng 
Published: July 2002

China is a large country, occupying 9,600,000 km2. It lies between longitudes 73°40′E and 135° 05′E, a distance of some 5,200 km. Mountainous in the west and flat in the east, the land surface of China slopes downward from west to east in a three-step staircase and can be divided into moist, semi-moist, semi-arid and arid regions from the east coast to the inland north-west respectively. From north to south, China covers frigid, temperate, subtropical and tropical zones. All of this variation in geographical and climate conditions combine to give it a high diversity of fauna and flora.The country is rich in Galliformes. Sixty-one species of two families (Tetraonidae and Phasianidae) are found in the country (Cheng 1994), which is about 22% of the 277 Galliformes species of the world (Sibley and Monroe 1990). In recent decades, as a result of big changes in the environments and the increasing human activities, the ranges of Chinese Galliformes have decreased and the population densities have declined (Zheng and Zhang 1993). The status of the country's Galliformes was assessed in the mid 1990s as part of two global reviews: through the compilation of IUCN/World Pheasant Association (WPA) action plans for pheasants (McGowan and Garson 1995) and partridges (McGowan et al., 1995), and through the revision of BirdLife International's list of threatened bird species (Collar et al. 1994). Both assessments considered that a high proportion of the world's threatened Galliformes occurred in China.
Categorical logic of names and abstraction in action calculi
Authors: PAVLOVIĆ DUšKO 
Published: July 2002

Milner's action calculus implements abstraction in monoidal
categories, so that familiar
λ-calculi can be subsumed together with the π-calculus and the
Petri nets. Variables are
generalised to names, which allow only a restricted form of substitution.In the present paper, the well-known categorical semantics of the
λ-calculus is generalised to
the action calculus. A suitable functional completeness theorem for
symmetric monoidal
categories is proved: we determine the conditions under which the abstraction
is definable.
Algebraically, the distinction between the variables and the names boils
down to the
distinction between the transcendental and the algebraic elements. The
former lead to
polynomial extensions, like, for example, the ring ℤ[x];
the latter lead to algebraic
extensions like ℤ[√2] or ℤ[i].Building upon the work of P. Gardner, we introduce action categories,
and show that they
are related to the static action calculus in exactly the same way as
cartesian closed categories
are related to the λ-calculus. Natural examples of this structure
arise
from allegories and cartesian bicategories. On the other hand, the free
algebras
for any commutative Moggi
monad form an action category. The general correspondence of action calculi
and Moggi
monads will be worked out in a sequel to this work.
How it all began: the monetary and financial architecture of Europe during the first global capital markets, 1648–1815
Authors: NEAL LARRY 
Published: July 2002

Larry Neal, How it all began: the monetary and financial architecture of Europe during the first global capital markets, 1648–1815The Treaty of Westphalia created the modern nation-state system of Europe and set the stage for the long-term success of financial capitalism. The new sovereign states experimented with competing monetary regimes during their wars over the next century and two-thirds while they extended and perfected the financial innovations in war finance developed during the Thirty Years War. The Dutch maintained fixed exchange rates, the French insisted on exercising monetary independence, while the English placed priority on free movement of international capital. In struggling with the
trilemma of choosing among the goals of maintaining fixed exchange rates, monetary independence and free movement of capital, the governments of early modern Europe learned many valuable lessons. By the time of the Napoleonic wars, the
innovations that emphasised reliance on financial markets rather than on financial institutions proved their superiority.
Detection of hail by means of polarimetric radar data and hailpads: results from four storms
Authors: Nanni S , Mezzasalma P , Alberoni P P 
Published: July 2002

AbstractHailfall is one of the most dangerous and damaging phenomena associated with severe thunderstorms. Its remote identification is still under investigation, especially by means of polarimetric radar data. The need to use polarimetric measurements is a limit to operational implementation of the techniques developed up till now. The routine sampling of radar allows the computation of the differential hail signal HDR (Aydin et al., 1986) every 15 minutes. The assessment of the HDR is performed by comparison with the ground truth from a hailpad network. The spatial resolution of this network is quite coarse (one pad per 16 km2) for the collection of all the hail shafts, as they generally have a small horizontal extent and are short lived. Such bounds have been considered in the analysis of four large hailfalls recorded in 1997. This study reveals also the limitation on radar hail detection arising from the frequent occurrence of strong differential attenuation. Nevertheless, to identify regions where a sharp rain–hail transition occurs, polarimetric measurements work much better than algorithms based only on horizontal reflectivity. Results show that use of HDR gives a high probability of correct hail detection as well as an acceptable number of false alarms. Copyright © 2000 Royal Meteorological Society
The hurricane‐like Mediterranean cyclone of January 1995
Authors: Pytharoulis Ioannis , Craig George C , Ballard Susan P 
Published: July 2002

AbstractThe development of a hurricane‐like vortex over the Mediterranean Sea was studied using (mainly) the UK Met. Office Unified Model. The Mediterranean cyclone formed in the morning of 15 January 1995 over the sea between Greece and Sicily. Strong convection was observed prior to its genesis. During the longest part of the cyclone's lifetime, strong surface fluxes and, as a result, deep convection existed in its vicinity. Its track was influenced by the surface fluxes and the flow in the wider region. The forecast of the mesoscale and limited‐area models reproduced the general characteristics of the actual system as they appeared at the surface and upper‐air charts and at the satellite imagery. The investigation of the cyclone's characteristics gave strong evidence (including an ‘eye’ and a warm core) to support the initial assertion that it was similar to tropical cyclones and some polar lows. Baroclinic instability does not seem particularly important, although the cyclone formed at the edge of a baroclinic zone. A numerical experiment showed the vortex did not develop in the absence of surface heat and moisture fluxes. Another experiment showed that sensible and latent heat fluxes were equally important in its development. Copyright © 2000 Royal Meteorological Society
The Large-Scale Organization of the Centromeric Region inBetaSpecies
Authors: Gindullis Frank , Desel Christine , Galasso Incoronata , Schmidt Thomas 
Published: July 2002

In higher eukaryotes, the DNA composition of centromeres displays a high degree of variation, even between chromosomes of a single species. However, the long-range organization of centromeric DNA apparently follows similar structural rules. In our study, a comparative analysis of the DNA at centromeric regions ofBetaspecies, including cultivated and wild beets, was performed using a set of repetitive DNA sequences. Our results show that these regions inBetagenomes have a complex structure and consist of variable repetitive sequences, including satellite DNA, Ty3-gypsy-like retrotransposons, and microsatellites. Based on their molecular characterization and chromosomal distribution determined by fluorescent in situ hybridization (FISH), centromeric repeated DNA sequences were grouped into three classes. By high-resolution multicolor-FISH on pachytene chromosomes and extended DNA fibers we analyzed the long-range organization of centromeric DNA sequences, leading to a structural model of a centromeric region of the wild beet speciesBeta procumbens. The chromosomal mutants PRO1 and PAT2 contain a single wild beet minichromosome with centromere activity and provide, together with cloned centromeric DNA sequences, an experimental system toward the molecular isolation of individual plant centromeres. In particular, FISH to extended DNA fibers of the PRO1 minichromosome and pulsed-field gel electrophoresis of large restriction fragments enabled estimations of the array size, interspersion patterns, and higher order organization of these centromere-associated satellite families. Regarding the overall structure,Betacentromeric regions show similarities to their counterparts in the few animal and plant species in which centromeres have been analyzed in detail.[The sequence data described in this paper have been submitted to the EMBL data library under accession nos.AJ278751,AJ278752, andAJ243337.
Pharmacological Analysis of Nod Factor-Induced Calcium Spiking inMedicago truncatula. Evidence for the Requirement of Type IIA Calcium Pumps and Phosphoinositide Signaling
Authors: Engstrom Eric M. , Ehrhardt David W. , Mitra Raka M. , Long Sharon R. 
Published: July 2002

Abstract
Bacterial Nod factors trigger a number of cellular responses in root hairs of compatible legume hosts, which include periodic, transient increases in cytosolic calcium levels, termed calcium spiking. We screened 13 pharmaceutical modulators of eukaryotic signal transduction for effects on Nod factor-induced calcium spiking. The purpose of this screening was 2-fold: to implicate enzymes required for Nod factor-induced calcium spiking in Medicago sp., and to identify inhibitors of calcium spiking suitable for correlating calcium spiking to other Nod factor responses to begin to understand the function of calcium spiking in Nod factor signal transduction. 2-Aminoethoxydiphenylborate, caffeine, cyclopiazonic acid (CPA), 2,5-di-(t-butyl)-1,4-hydroquinone, and U-73122 inhibit Nod factor-induced calcium spiking. CPA and U-73122 are inhibitors of plant type IIA calcium pumps and phospholipase C, respectively, and implicate the requirement for these enzymes in Nod factor-induced calcium spiking. CPA and U-73122 inhibit Nod factor-induced calcium spiking robustly at concentrations with no apparent toxicity to root hairs, making CPA and U-73122 suitable for testing whether calcium spiking is causal to subsequent Nod factor responses.