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Hydrologic Data for Urban Studies in The Austin, Texas, Metropolitan Area, 1982
The technical report mentions Waller Creek as a main stream in the study area, but a preliminary search provides no results to specific data from the site.Hydrologic investigations of urban watersheds in Texas were begun by the U.S. Geological Survey in 1954. Studies are now in progress in Austin, and Houston. Studies have been completed in the Dallas, Fort Worth, and San Antonio areas.
The Geological Survey, in cooperation with the Texas Department of Water Resources, began hydrologic studies in the Austin urban area in 1954. In cooperation with the city of Austin, the program was expanded in 1975 to include additional streamflow and rainfall gaging stations, and the collection of surface water-quality data. In 1978, the program was expanded to include a ground-water resources study of the South Austin metropolitan area in the Balcones Fault Zone.Waller Creek Working Grou
Combining observations with acoustic swath bathymetry and backscatter to map seabed sediment texture classes: the empirical best linear unbiased predictor
Seabed sediment texture can be mapped by geostatistical prediction from limited direct observations such as grab-samples. A geostatistical model can provide local estimates of the probability of each texture class so the most probable sediment class can be identified at any unsampled location, and the uncertainty of this prediction can be quantified. In this paper we show, in a case study off the northeast coast of England, how swath bathymetry and backscatter can be incorporated into a geostatistical linear mixed model (LMM) as fixed effects (covariates).
Parameters of the LMM were estimated by maximum likelihood which allowed us to show that both covariates provided useful information. In a cross-validation, each observation was predicted from the rest using the LMMs with (i) no covariates, or (ii) bathymetry and backscatter as covariates. The proportion of cases in which the most probable class according to the prediction corresponded to the observed class was increased (from 58% to 65% of cases) by including the covariates which also increased the information content of the predictions, measured by the entropy of the class probabilities. A qualitative assessment of the geostatistical results shows that the model correctly predicts, for example, the occurrence of coarser sediment over discrete glacial sediment landforms, and muddier sediment in relatively quiescent, localized deep water environments. This demonstrates the potential for assimilating geophysical data with direct observations by the LMM, and could offer a basis for a routine mapping procedure which incorporates these and other ancillary information such as manually-interpreted geological and geomorphological maps
Regulation of AE2-mediated Cl− Transport by Intracellular or by Extracellular pH Requires Highly Conserved Amino Acid Residues of the AE2 NH2-terminal Cytoplasmic Domain
We reported recently that regulation by intracellular pH (pHi) of the murine Cl−/HCO3− exchanger AE2 requires amino acid residues 310–347 of the polypeptide's NH2-terminal cytoplasmic domain. We have now identified individual amino acid residues within this region whose integrity is required for regulation of AE2 by pH. 36Cl− efflux from AE2-expressing Xenopus oocytes was monitored during variation of extracellular pH (pHo) with unclamped or clamped pHi, or during variation of pHi at constant pHo. Wild-type AE2–mediated 36Cl− efflux was profoundly inhibited by acid pHo, with a value of pHo(50) = 6.87 ± 0.05, and was stimulated up to 10-fold by the intracellular alkalinization produced by bath removal of the preequilibrated weak acid, butyrate. Systematic hexa-alanine [(A)6]bloc substitutions between aa 312–347 identified the greatest acid shift in pHo(50) value, ∼0.8 pH units in the mutant (A)6342–347, but only a modest acid-shift in the mutant (A)6336–341. Two of the six (A)6 mutants retained normal pHi sensitivity of 36Cl− efflux, whereas the (A)6 mutants 318–323, 336–341, and 342–347 were not stimulated by intracellular alkalinization. We further evaluated the highly conserved region between aa 336–347 by alanine scan and other mutagenesis of single residues. Significant changes in AE2 sensitivity to pHo and to pHi were found independently and in concert. The E346A mutation acid-shifted the pHo(50) value to the same extent whether pHi was unclamped or held constant during variation of pHo. Alanine substitution of the corresponding glutamate residues in the cytoplasmic domains of related AE anion exchanger polypeptides confirmed the general importance of these residues in regulation of anion exchange by pH. Conserved, individual amino acid residues of the AE2 cytoplasmic domain contribute to independent regulation of anion exchange activity by pHo as well as pHi
Phytohemagglutinin-Induced Mitotic Index in Blood Lymphocytes: A Potential Biomarker for Breast Cancer Risk
Background Cell proliferation is associated with the pathogenesis of cancer because it provides opportunities for accumulating genetic mutations. However, biomarkers of cell proliferation in response to environmental stimuli have not been adequately explored for breast cancer risk. Methods In a case-control study of 200 breast cancer patients and 360 healthy controls, we investigated the association between phytohemagglutinin (PHA)-induced mitotic index in blood lymphocyte and breast cancer risk. Results Having high mitotic index (>3.19%) was associated with an increased risk of breast cancer, with adjusted odds ratios (95% confidence interval) of 1.54 (1.03–2.30) and 2.03 (1.18–3.57) for all women and post-menopausal women, respectively. Mitotic index was correlated with some reproductive factors and body mass index in controls. Conclusions Our data suggest increased PHA-induced mitotic index in blood lymphocytes is associated with an increased breast cancer risk and that this association may be modulated by reproductive and other hormones
Second-order corrections to noncommutative spacetime inflation
We investigate how the uncertainty of noncommutative spacetime affects on
inflation. For this purpose, the noncommutative parameter is taken to
be a zeroth order slow-roll parameter. We calculate the noncommutative power
spectrum up to second order using the slow-roll expansion. We find corrections
arisen from a change of the pivot scale and the presence of a variable
noncommutative parameter, when comparing with the commutative power spectrum.
The power-law inflation is chosen to obtain explicit forms for the power
spectrum, spectral index, and running spectral index. In cases of the power
spectrum and spectral index, the noncommutative effect of higher-order
corrections compensates for a loss of higher-order corrections in the
commutative case. However, for the running spectral index, all higher-order
corrections to the commutative case always provide negative spectral indexes,
which could explain the recent WMAP data.Comment: 15 pages, no figure, version published in PR
Second-order corrections to slow-roll inflation in the brane cosmology
We calculate the power spectrum, spectral index, and running spectral index
for the RS-II brane inflation in the high-energy regime using the slow-roll
expansion. There exist several modifications. As an example, we take the
power-law inflation by choosing an inverse power-law potential. When comparing
these with those arisen in the standard inflation, we find that the power
spectrum is enhanced and the spectral index is suppressed, while the running
spectral index becomes zero as in the standard inflation. However, since
second-order corrections are rather small, these could not play a role of
distinguishing between standard and brane inflations.Comment: 6 page
Are they ‘worth their weight in gold’? Sport for older adults: benefits and barriers of their participation for sporting organisations
The ageing global population has led to an increased focus on health for older adults. However, older adults have not been a specific priority for some sporting organisations (SOs). Thus, there is an emerging opportunity for this age group to be considered within international sport policy. The aim of this study was to understand the benefits and barriers that SOs encounter when engaging older adults. Eight focus group interviews (n = 49) were held with representatives of Australian national sporting organisations (NSOs), and older adults who were either sport club or non-sport club members. The socioecological model domains, interpersonal, organisational and policy, were used as a framework for thematic analysis, and organisational capacity building concepts were utilised to explain the findings. Common perceived benefits included interpersonal benefits (intergenerational opportunities and role models) and organisational benefits (volunteering, financial contributions and maximised facility usage) for engaging older adults. Common perceived barriers included interpersonal barriers (competing priorities and perceived societal expectations), organisational barriers (lack of appropriate playing opportunities, lack of facility access and lack of club capacity) and policy barriers (strategic organisational focus on children and elite sport and risk management). Whilst participation in sport is not common for older adults, their involvement can be invaluable for sport clubs. It is not anticipated that any policy focus on older adults will significantly increase active participation for this age group. However, any increase in older adults’ sport participation either through actively playing, supporting family and friends and/or volunteering will contribute to the positive health of individuals, sport clubs and the community.Peer reviewedFinal Accepted Versio
Electromagnetic field angular momentum in condensed matter systems
Various electromagnetic systems can carry an angular momentum in their {\bf
E} and {\bf B} fields. The electromagnetic field angular momentum (EMAM) of
these systems can combine with the spin angular momentum to give composite
fermions or composite bosons. In this paper we examine the possiblity that an
EMAM could provide an explanation of the fractional quantum Hall effect (FQHE)
which is complimentary to the Chern-Simons explanation. We also examine a toy
model of a non-BCS superconductor (e.g. high superconductors) in terms of
an EMAM. The models presented give a common, simple picture of these two
systems in terms of an EMAM. The presence of an EMAM in these systems might be
tested through the observation of the decay modes of a charged, spin zero
unstable particle inside one of these systems.Comment: 17 pages, no figures, to be published in Phys. Rev.
Anisotropic magnetization, specific heat and resistivity of RFe2Ge2 single crystals
We have grown RFe2Ge2 single crystals for R = Y and ten members of the
lanthanide series (Pr, Nd, Sm, Gd-Tm, Lu) using Sn flux as the solvent. The
method yields clean, high quality crystal plates as evidenced by residual
resistivities and RRR values in the range of 3-12 uOhm cm and 20-90
respectively. The crystals are also virtually free of magnetic impurities or
secondary phases, allowing the study of the intrinsic anisotropic magnetic
behavior of each compound. Characterization was made with X-Ray diffraction,
and temperature and field dependent magnetization, specific heat and
resistivity. Very strong anisotropies arising mostly from CEF effects were
observed for all magnetic rare earths except Gd. Antiferromagnetic ordering
occurred at temperatures between 16.5 K (Nd) and 1.1 K (Ho) that roughly scale
with the de Gennes factor for the heavy rare earths. For some members there is
also a lower temperature transition associated with changes in the magnetic
structure. Tm did not order down to 0.4 K, and appears to be a van Vleck
paramagnet. All members which ordered above 2 K showed a metamagnetic
transition at 2 K for fields below 70 kOe. The calculated effective moments per
rare earth atom are close to the expected free ion values of R^3+ except for Sm
which displays anomalous behavior in the paramagnetic state. The non-magnetic
members of this series (Y, Lu) are characterized by an unusually large
electronic specific heat coefficient (gamma ~ 60 mJ/mol K^2) and
temperature-independent susceptibility term (chi_0 ~ 0.003 emu/mol), indicative
of a relatively large density of states at the Fermi surface.Comment: 34 pages, 13 figures, 1 table, submitted to J. Magn. Magn. Mate
Nonlocal Equation of State in Anisotropic Static Fluid Spheres in General Relativity
We show that it is possible to obtain credible static anisotropic spherically
symmetric matter configurations starting from known density profiles and
satisfying a nonlocal equation of state. These particular types of equation of
state describe, at a given point, the components of the corresponding
energy-momentum tensor not only as a function at that point, but as a
functional throughout the enclosed configuration. To establish the physical
plausibility of the proposed family of solutions satisfying nonlocal equation
of state, we study the constraints imposed by the junction and energy
conditions on these bounded matter distributions.
We also show that it is possible to obtain physically plausible static
anisotropic spherically symmetric matter configurations, having nonlocal
equations of state\textit{,}concerning the particular cases where the radial
pressure vanishes and, other where the tangential pressures vanishes. The later
very particular type of relativistic sphere with vanishing tangential stresses
is inspired by some of the models proposed to describe extremely magnetized
neutron stars (magnetars) during the transverse quantum collapse.Comment: 21 pages, 1 figure, minor changes in the text, references added, two
new solutions studie
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