19,853 research outputs found
Configurational Temperature in Membrane Simulations Using Dissipative Particle Dynamics
The use of excessively long timesteps in dissipative particle dynamics
simulations may produce simulation artifacts due to the generation of
configurations which are not representative of the desired canonical ensemble.
The configurational temperature, amongst other quantities, may be used to
assess the extent of the deviation from equilibrium. This paper presents
results for simulations of models of water, and lipid bilayer membranes, to
illustrate the nature of the problems.Comment: 13 pages, 7 figures, RevTex
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Offshoring the Nation's water
When the ten regional water authorities in England and Wales were floated on the London Stock Exchange in 1989, a shift in ownership inevitably followed from the privatization of household water. The public listing of shares in water companies initially created a wide distribution of ownership across the UK population, with preference given to those who paid the water bills. Controls were put in place to ensure that no one individual or company could monopolize the shareholdings, with the UK government retaining a ‘golden share’ precisely to avoid such an outcome. Once those shares were relinquished by the government in 1994, however, the ownership of the nation’s water started to shift abroad, with foreign investors largely attracted by the low risk, stable returns on offer. Some two decades on, with seven of the ten water authorities now in foreign ownership, the contrast from the idea of a British shareholding public that drove the early UK privatisations could not be greater
Realizing the Potential of Marine Biotechnology : Challenges and Opportunities
A paid open access option is available for this journal. Author's final version or publisher's version/PDF Authors may deposit in funding agency designated repository after 12 monthsPeer reviewedPublisher PD
A note on muscle composition and colour of Holstein-Friesian, Piedmontese × Holstein-Friesian and Romagnola × Holstein-Friesian steers.
peer-reviewedHolstein-Friesian (HF), Piedmontese × Holstein-Friesian (PM) and Romagnola ×
Holstein-Friesian (RO) steers were compared for muscle composition and colour. A
total of 120 steers in a 3 breed types (HF, PM and RO) × 2 feeding levels (low and
high) × 2 finishing periods (short, S and extended, E) factorial experiment were used.
Three samples of m. longissimus were taken for chemical analysis, measurement of drip
loss and Hunterlab colour measurements. Muscle moisture and protein concentrations
were lower, and lipid concentration was higher for HF than for PM and RO, which were
similar. There were no effects of feeding level on chemical composition, but after blooming
all colour values except hue were lower for the higher feeding level. The E finishing
period reduced moisture, protein, drip-loss, L (lightness), a (redness) and chroma
values. It is concluded that PM and RO had similar muscle composition but HF had
a higher lipid concentration. Feeding level had few effects on muscle composition, but
extended finishing increased all measures of fatness and reduced colour values
Characterising submonolayer deposition via visibility graphs
We use visibility graphs as a tool to analyse the results of kinetic Monte
Carlo (kMC) simulations of submonolayer deposition in a one-dimensional point
island model. We introduce an efficient algorithm for the computation of the
visibility graph resulting from a kMC simulation and show that from the
properties of the visibility graph one can determine the critical island size,
thus demonstrating that the visibility graph approach, which implicitly
combines size and spatial data, can provide insights into island nucleation and
growth processes
Clinical features of pneumonia in extreme old age
The clinical features of 70 people over the age of 85 with radiologically positive pneumonia were studied. It was shown that the classical presenting symptoms of pneumonia were often absent and 81 % had one or more acute ’geriatric’ features such as acute confusion, recent onset of falls, recent worsening immobility or recent onset of incontinence, at the time of presentation. An increased risk of mortality was associated with acute confusion, dementia, central cyanosis and long term immobility. Well kept body temperature and respiratory rate charts provide a useful early warning of possible pneumonia in very elderly in patients and the finding of a raised body temperature with a raised respiratory rate should always prompt the need to rule out lower respiratory tract infection.peer-reviewe
Ecology of fishes in Upper Newport Bay, California: seasonal dynamics and community structure
A total of 366 bimonthly (January 1978-January 1979) samples taken with six types of gear (otter trawl, gill net, bag seine, small seine, drop net, square enclosure - all
with replication except the gill net) at four stations in
upper Newport Bay, California yielded 51,816 fishes belonging to 46 species and weighing over 353 kg. Atherinops affinis (topsmelt) was the most abundant species accounting for 76% of total individuals. Seven species, all of low trophic levels, made up over 97% of the total catch. Mugil cephalus (striped mullet) ranked first in biomass (= 36% of the total) with six species accounting for more than 80% of the total biomass. The largest number of individuals (71%) was collected with the bag seine, the greatest number of species (35) was captured with the otter trawl and the largest percentage of the biomass (56%)was obtained with the gill net. Species richness, number of individuals and biomass were lowest in January (1978 or 1979) or March and highest in July (numbers, biomass) or September (species). Bimonthly diversity (H') values ranged from 0.48 to 2.17 (overall value 1.05) and tended to be inversely related to abundance levels. Species richness was greatest at Station 4 (the lowermost station) and least at Station 1 (the uppermost station). Numbers of individuals and biomass peaked at Station 2 and reached lowest levels at Station 1.
Length-frequency analysis of six of the most abundant
species indicated utilization of the upper bay by two or
more stages in the life history of these species.
More than 92,000 eggs belonging to seven taxa and an
unknown category and 426 larvae from 20 taxa were collected
with a 0.5 m net mounted on an epibenthic sled during the
same bimonthly periods and at the same stations as the
juvenile/adult samples. Most of the eggs were collected at
Station 2 in May with the numbers overwhelmingly dominated
by those of Anchoa compressa (deepbody anchovy) (99.7% of
total numbers). The most abundant larva was that of
Clevelandia ios (arrow goby). Nearly 60% of the total
larval catch was made up of members of the family Gobiidae.
Larval taxa and individuals were fewest in January (1978).
The number of taxa was highest in March, September and
January (1979) whereas larval numbers peaked in May. The
number of taxa and of individual larvae varied only slightly
among the four stations.
Asymptotic species accumulation curves indicated adequate sampling of juvenile/adult fishes. Cluster analysis
produced eight species groups of resident and periodic
species that variously utilize the three main habitats
(channel, inshore, pannes) in the upper bay. Species
richness and abundance were positively correlated with both
temperature and salinity. Temperature, salinity and depth
of capture were frequently correlated with individual species abundances and were used in combination to partially explain the spatial utilization of species and species groups.
The upper bay fish community is important and worthy of
preservation for at least three reasons: 1) it contains
species assemblages not duplicated in any other coastal
environment; 2) it contains life history stages of a
variety of coastal fish species; and 3) it contains large
populations of small, low-trophic level species and juveniles of other species which serve as forage for larger, predatory species that are frequently of economic importance. Members of the fish community respond noticeably to altered environmental conditions such as the heavy rainfall (and accompanying low salinity and high turbidity) that occurred during the early months of 1978. The short and long term, as yet often unpredictable, fluctuations in the populations emphasize the need for periodic monitoring and for the development of a mathematical model of the fish community if it is to be thoroughly understood and properly managed. (102pp.
Maximally Symmetric Spin-Two Bitensors on and
The transverse traceless spin-two tensor harmonics on and may be
denoted by . The index labels the (degenerate) eigenvalues
of the Laplacian and the other indices. We compute the bitensor
where are distinct
points on a sphere or hyperboloid of unit radius. These quantities may be used
to find the correlation function of a stochastic background of gravitational
waves in spatially open or closed Friedman-Robertson-Walker cosmologies.Comment: 12 pages, RevTeX, uuencoded compressed .tex file, minor typos
correcte
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