5,810 research outputs found
Transient cavities and the excess chemical potentials of hard-spheroid solutes in dipolar hard sphere solvents
Monte Carlo computer simulations are used to study transient cavities and the
solvation of hard-spheroid solutes in dipolar hard sphere solvents. The
probability distribution of spheroidal cavities in the solvent is shown to be
well described by a Gaussian function, and the variations of fit parameters
with cavity elongation and solvent properties are analyzed. The excess chemical
potentials of hard-spheroid solutes with aspect ratios in the range , and with volumes between one and twenty times that of a solvent
molecule, are presented. It is shown that for a given molecular volume and
solvent dipole moment (or temperature) a spherical solute has the lowest excess
chemical potential and hence the highest solubility, while a prolate solute
with aspect ratio should be more soluble than an oblate solute with aspect
ratio . For a given solute molecule, the excess chemical potential
increases with increasing temperature; this same trend is observed in the case
of hydrophobic solvation. To help interpret the simulation results, comparison
is made with a scaled-particle theory that requires prior knowledge of a
solute-solvent interfacial tension and the pure-solvent equation of state,
which parameters are obtained from simulation results for spherical solutes.
The theory shows excellent agreement with simulation results over the whole
range of solute elongations considered.Comment: 10 pages, 10 figure
Arm cavity resonant sideband control for laser interferometric gravitational wave detectors
We present a new optical control scheme for a laser interferometric gravitational wave detector that has a high degree of tolerance to interferometer spatial distortions and noise on the input light. The scheme involves resonating the rf sidebands in an interferometer arm cavity
Ninja data analysis with a detection pipeline based on the Hilbert-Huang Transform
The Ninja data analysis challenge allowed the study of the sensitivity of
data analysis pipelines to binary black hole numerical relativity waveforms in
simulated Gaussian noise at the design level of the LIGO observatory and the
VIRGO observatory. We analyzed NINJA data with a pipeline based on the Hilbert
Huang Transform, utilizing a detection stage and a characterization stage:
detection is performed by triggering on excess instantaneous power,
characterization is performed by displaying the kernel density enhanced (KD)
time-frequency trace of the signal. Using the simulated data based on the two
LIGO detectors, we were able to detect 77 signals out of 126 above SNR 5 in
coincidence, with 43 missed events characterized by signal to noise ratio SNR
less than 10. Characterization of the detected signals revealed the merger part
of the waveform in high time and frequency resolution, free from time-frequency
uncertainty. We estimated the timelag of the signals between the detectors
based on the optimal overlap of the individual KD time-frequency maps, yielding
estimates accurate within a fraction of a millisecond for half of the events. A
coherent addition of the data sets according to the estimated timelag
eventually was used in a characterization of the event.Comment: Accepted for publication in CQG, special issue NRDA proceedings 200
Frequency noise and intensity noise of next-generation gravitational-wave detectors with RF/DC readout schemes
The sensitivity of next-generation gravitational-wave detectors such as
Advanced LIGO and LCGT should be limited mostly by quantum noise with an
expected technical progress to reduce seismic noise and thermal noise. Those
detectors will employ the optical configuration of resonant-sideband-extraction
that can be realized with a signal-recycling mirror added to the Fabry-Perot
Michelson interferometer. While this configuration can reduce quantum noise of
the detector, it can possibly increase laser frequency noise and intensity
noise. The analysis of laser noise in the interferometer with the conventional
configuration has been done in several papers, and we shall extend the analysis
to the resonant-sideband-extraction configuration with the radiation pressure
effect included. We shall also refer to laser noise in the case we employ the
so-called DC readout scheme.Comment: An error in Fig. 10 in the published version in PRD has been
corrected in this version; an erratum has been submitted to PRD. After
correction, this figure reflects a significant difference in the ways RF and
DC readout schemes are susceptible to laser noise. In addition, the levels of
mirror loss imbalances and input laser amplitude noise have also been updated
to be more realistic for Advanced LIG
Search for Gravitational Waves from Intermediate Mass Binary Black Holes
We present the results of a weakly modeled burst search for gravitational waves from mergers of non-spinning intermediate mass black holes (IMBH) in the total mass range 100-450 solar Mass and with the component mass ratios between 1:1 and 4:1. The search was conducted on data collected by the LIGO and Virgo detectors between November of 2005 and October of 2007. No plausible signals were observed by the search which constrains the astrophysical rates of the IMBH mergers as a function of the component masses. In the most efficiently detected bin centered on 88 + 88 solar Mass , for non-spinning sources, the rate density upper limit is 0.13 per Mpc(exp 3) per Myr at the 90% confidence level
The expression pattern of MUC1 (EMA) is related to tumour characteristics and clinical outcome of invasive ductal breast carcinoma
Aims: To clarify MUC1 patterns in invasive ductal breast carcinoma and to relate them to clinicopathological parameters, coexpression of other biological markers and prognosis. Methods and results: Samples from 243 consecutive patients with primary ductal carcinoma were incorporated into tissue microarrays (TMAs). Slides were stained for MUC1, oestrogen receptor (ER), progesterone receptor (PR), Her2/neu, p53 and cyclin D1. Apical membrane MUC1 expression was associated with smaller tumours (P = 0.001), lower tumour grades (P < 0.001), PR positivity (P = 0.003) and increased overall survival (OS; P = 0.030). Diffuse cytoplasmic MUC1 expression was associated with cyclin D1 positivity (P = 0.009) and increased relapse-free survival (RFS; P = 0.034). Negativity for MUC1 was associated with ER negativity (P = 0.004), PR negativity (P = 0.001) and cyclin D1 negativity (P = 0.009). In stepwise multivariate analysis MUC1 negativity was an independent predictor of both RFS [hazard ratio (HR) 3.5, 95% confidence interval (CI) 1.5, 8.5; P = 0.005] and OS (HR 14.7, 9 5% Cl 4.9, 44. 1; P < 0.001). Conclusions: The expression pattern of MUC1 in invasive ductal breast carcinoma is related to tumour characteristics and clinical outcome. In addition, negative MUC1 expression is an independent risk factor for poor RFS and OS, besides 'classical' prognostic indicators
A comparison of cultural ecosystem service survey methods within South England
AbstractAcross all societies, humans depend on goods received from nature, termed ecosystem services. However, cultural ecosystem services (CES), the non-material benefits people obtain from ecosystems, are often overlooked in land-use decision making due to their intangible nature. This study aimed to evaluate three possible survey methods for site-based CES data collection; language-based supervised surveys (in which interviewers conduct surveys in real-time, recording verbal responses), language-based unsupervised surveys (respondents complete written surveys without an interviewer), and image-based unsupervised surveys (respondents complete surveys via image selection without an interviewer). Language-based supervised surveys were found to be more efficient in collecting CES data than language-/image-based unsupervised surveys, with a mean completion rate over 1.5-fold greater than either unsupervised survey; furthermore, survey completion was over twice as fast, and less than a sixth of the monetary cost per respondent compared to unsupervised surveys. The site-based assessment developed in this study provides robust data, and is shown to provide rapid and useful feedback to land-use decision makers. We recommend that rapid, site-based assessment methods are utilised to collect the information required to support CES-related decision making
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