1,450 research outputs found
Prediction Possibility in the Fractal Overlap Model of Earthquakes
The two-fractal overlap model of earthquake shows that the contact area
distribution of two fractal surfaces follows power law decay in many cases and
this agrees with the Guttenberg-Richter power law. Here, we attempt to predict
the large events (earthquakes) in this model through the overlap time-series
analysis. Taking only the Cantor sets, the overlap sizes (contact areas) are
noted when one Cantor set moves over the other with uniform velocity. This
gives a time series containing different overlap sizes. Our numerical study
here shows that the cumulative overlap size grows almost linearly with time and
when the overlapsizes are added up to a pre-assigned large event (earthquake)
and then reset to `zero' level, the corresponding cumulative overlap sizes
grows upto some discrete (quantised) levels. This observation should help to
predict the possibility of `large events' in this (overlap) time series.Comment: 6 pages, 6 figures. To be published as proc. NATO conf. CMDS-10,
Soresh, Israel, July 2003. Eds. D. J. Bergman & E. Inan, KLUWER PUB
Estimating Entropy of Liquids from Atom-Atom Radial Distribution Functions: Silica, Beryllium Fluoride and Water
Molecular dynamics simulations of water, liquid beryllium fluoride and silica
melt are used to study the accuracy with which the entropy of ionic and
molecular liquids can be estimated from atom-atom radial distribution function
data. All three systems are known to display similar liquid-state thermodynamic
and kinetic anomalies due to a region of anomalous excess entropy behaviour
where entropy rises on isothermal compression. The pair correlation entropy is
demonstrated to be sufficiently accurate that the density-temperature regime of
anomalous behaviour as well as the strength of the entropy anomaly can be
predicted reliably for both ionic melts as well as different rigid-body pair
potentials for water. Errors in the total thermodynamic entropy for ionic melts
due to the pair correlation approximation are of the order of 10% or less for
most state points but can be significantly larger in the anomalous regime at
very low temperatures. In the case of water, as expected given the rigid-body
constraints for a molecular liquids, the pair correlation approximation causes
significantly larger errors, between 20 and 30%, for most state points.
Comparison of the excess entropy, Se, of ionic melts with the pair correlation
entropy, S2, shows that the temperature dependence of Se is well described by T
??2=5 scaling across both the normal and anomalous regimes, unlike in the case
of S2. As a function of density, the Se(rho) curves shows only a single maximum
while the S2(rho) curves show both a maximum and a minimum. These differences
in the behaviour of S2 and Se are due to the fact that the residual
multiparticle entropy, delta(S) = Se - S2, shows a strong negative correlation
with tetrahedral order in the anomalous regime.Comment: 30 pages, 8 figure
Recommended from our members
Urinary incontinence related to perineal muscle strength in the first trimester of pregnancy: cross-sectional study
Objective To analyze pelvic floor muscle strength (PFMS), urinary continence and quality of life related to urinary incontinence (UI) of women in the first trimester of pregnancy. Method Cross-sectional study with a sample of 500 women who started prenatal care in a complementary healthcare facility in Guarulhos, state of São Paulo, from 2012 and 2013. Pelvic floor muscle strength was evaluated through perineometry. The pregnant women who presented UI answered the International Consultation on Incontinence Questionnaire-Short Form (ICIQ-SF). Results It was found that maternal age (OR=1.06; CI95% 1.02-1.11) and prior UI (OR=15.12; 95%CI 8.19-27.92) are the variables that, in tandem, best explain the occurrence of UI at the beginning of pregnancy. The mean score on the ICIQ-SF was 8.2 (SD=3.9), considered a moderate impact on quality of life. Conclusion Older pregnant women with prior UI are more likely to have UI in the first trimester of pregnancy.
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Consequences of Kaizen Practices in MSMEs in the Philippines: The Case of the Manufacturing Productivity Extension Program (MPEX)
The Manufacturing Productivity Extension Program (MPEX) is a fully subsidized public-instigated productivity improvement program directed toward the micro, small, and medium enterprise (MSME) sector. While not advertised and packaged as a Kaizen initiative, it has all the elements of the Kaizen philosophy. Based on survey responses from 64 MPEX beneficiaries and 47 non-MPEX beneficiaries, the study showed that MPEX increased the number of product lines implying that Kaizen practice leads to product innovation among firms. Due to data and confounding issues, significant difference in productivity in terms of number of workers and sales per worker was not established. Firm asset size was implied to influence the capability to implement Kaizen. Regulatory compliance and customer demand requirements and entrepreneurial capacity are catalysts for enabling, adopting, and sustaining Kaizen implementation
JLab Measurements of the 3He Form Factors at Large Momentum Transfers
The charge and magnetic form factors, FC and FM, of 3He have been extracted
in the kinematic range 25 fm-2 < Q2 < 61 fm-2 from elastic electron scattering
by detecting 3He recoil nuclei and electrons in coincidence with the High
Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The
measurements are indicative of a second diffraction minimum for the magnetic
form factor, which was predicted in the Q2 range of this experiment, and of a
continuing diffractive structure for the charge form factor. The data are in
qualitative agreement with theoretical calculations based on realistic
interactions and accurate methods to solve the three-body nuclear problem
Measurement of GEp/GMp in ep -> ep to Q2 = 5.6 GeV2
The ratio of the electric and magnetic form factors of the proton, GEp/GMp,
was measured at the Thomas Jefferson National Accelerator Facility (JLab) using
the recoil polarization technique. The ratio of the form factors is directly
proportional to the ratio of the transverse to longitudinal components of the
polarization of the recoil proton in the elastic
reaction. The new data presented in this article span the range 3.5 < Q2 < 5.6
GeV2 and are well described by a linear Q2 fit. Also, the ratio QF2p/F1p
reaches a constant value above Q2=2 GeV2.Comment: 6 pages, 4 figures Added two names to the main author lis
Solution structure of a repeated unit of the ABA-1 nematode polyprotein allergen of ascaris reveals a novel fold and two discrete lipid-binding sites
Parasitic nematode worms cause serious health problems in humans and other animals. They can induce allergic-type immune responses, which can be harmful but may at the same time protect against the infections. Allergens are proteins that trigger allergic reactions and these parasites produce a type that is confined to nematodes, the nematode polyprotein allergens (NPAs). These are synthesized as large precursor proteins comprising repeating units of similar amino acid sequence that are subsequently cleaved into multiple copies of the allergen protein. NPAs bind small lipids such as fatty acids and retinol (Vitamin A) and probably transport these sensitive and insoluble compounds between the tissues of the worms. Nematodes cannot synthesize these lipids, so NPAs may also be crucial for extracting nutrients from their hosts. They may also be involved in altering immune responses by controlling the lipids by which the immune and inflammatory cells communicate. We describe the molecular structure of one unit of an NPA, the well-known ABA-1 allergen of Ascaris and find its structure to be of a type not previously found for lipid-binding proteins, and we describe the unusual sites where lipids bind within this structur
Multifunctionality of silver closo-boranes
Silver compounds share a rich history in technical applications including photography, catalysis, photocatalysis, cloud seeding and as antimicrobial agents. Here we present a class of silver compounds (Ag2B10H10 and Ag2B12H12) that are semiconductors with a bandgap at 2.3?eV in the green visible light spectrum. The silver boranes have extremely high ion conductivity and dynamic-anion facilitated Ag(+) migration is suggested based on the structural model. The ion conductivity is enhanced more than two orders of magnitude at room temperature (up to 3.2?mS?cm(-1)) by substitution with AgI to form new compounds. Furthermore, the closo-boranes show extremely fast silver nano-filament growth when excited by electrons during transmission electron microscope investigations. Ag nano-filaments can also be reabsorbed back into Ag2B12H12. These interesting properties demonstrate the multifunctionality of silver closo-boranes and open up avenues in a wide range of fields including photocatalysis, solid state ionics and nano-wire production
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