The sensitivity of gravitational wave interferometric detectors is ultimately limited by the quantum noise, which arises from the quantum nature of light and it is driven by vacuum fluctuations of ...the optical field entering from the dark port of the interferometer. One way to improve the sensitivity of gravitational wave interferometers is to inject squeezed vacuum into the dark port. This has been already demonstrated for the main gravitational wave detectors (GEO, Advanced LIGO and Advanced VIRGO). We are studying tricks to produce a "frequency- dependent squeezing": a standard method is to filter the squeezed optical field with one or more optical cavities (300 m long cavities). An alternative method using a pair of squeezed EPR (Einstein-Podolsky-Rosen) entangled beams to produce frequency-dependent squeezing by a non-degenerate OPO (Optical Parametric Oscillator) will be discussed in this paper. This method promises to achieve a frequency-dependent optimization of the injected squeezed light fields without the need for an external filter cavity.
Summary
We studied factors to determine the receipt of osteoporosis treatment in individuals with osteoporosis. Treatment was associated with age, gender, race, body mass index (BMI), family history, ...arthritis and thyroid problems, daily glucocorticoid use, number of prescriptions and healthcare visits, and insurance type.
Introduction
Osteoporosis is underrecognized and undertreated. Few studies have examined factors associated with osteoporosis treatment in a large, national sample of men and women.
Methods
We aggregated National Health and Nutrition Examination Survey (NHANES) data from 2005 to 2010 and created a subsample which included individuals 50 years or older who were identified to have osteoporosis either by self-report data or by bone density measurements. The primary outcome was the receipt of osteoporosis treatment either from self-report or from prescription records. Covariates included sociodemographics, clinical characteristics, and access to healthcare variables. Logistic regression analyses were performed to determine factors that associate with osteoporosis treatment.
Results
From a sample of 31,0134 participants, 1,133 subjects (3.65 %) met the study criteria. Treatment was associated with age (odds ratio (OR) = 1.14), gender (OR = 13.25), race (OR = 2.23, White vs. Black; OR = 1.76, other vs. Black), BMI (OR = 1.67, normal vs. obese; OR = 2.68, overweight vs. obese), family history of osteoporosis (OR = 1.94), arthritis (OR = 1.43), daily glucocorticoid use (OR = 1.43), number of prescriptions (OR = 1.01), and number of healthcare visits in the past year (OR = 1.44, 4–9 vs. 0–3 visits). All odds ratios were statistically significant.
Conclusion
A large number of individuals diagnosed with osteoporosis above the age of 50 remain untreated. It is important for healthcare providers to better assess older adults with osteoporosis, including individuals who frequently receive medical care.
Third-generation gravitational wave observatories will extend the lower frequency limit of the observation band toward 2 Hz, where new sources of gravitational waves, in particular intermediate-mass ...black holes (IMBH), will be detected. In this frequency region, seismic noise will play an important role, mainly through the so-called Newtonian noise, i.e., the gravity-mediated coupling between ground motion and test mass displacements. The signal lifetime of such sources in the detector is of the order of tens of seconds. In order to determine whether a candidate site to host the Einstein Telescope observatory is particularly suitable to observe such sources, it is necessary to estimate the probability distributions that, in the characteristic time scale of the signal, the sensitivity of the detector is not perturbed by Newtonian noise. In this paper, a first analysis is presented, focused on the Sos Enattos site (Sardinia, Italy), a candidate to host the Einstein Telescope. Starting from a long data set of seismic noise, this distribution is evaluated considering both the presently designed triangular ET configuration and also the classical ”L” configuration.
In this paper, we summarize the present state-of-the-art on the proof-of-principle experiment of frequency-dependent squeezing implemented through EPR entanglement for Virgo gravitational-wave ...detector and we introduce Virgo subsystem proposal for frequency-dependent squeezing, obtained with a compact apparatus and without the costs required by the infrastructure for the filter cavity.
Objectives
To examine the association between self‐reported sleep duration and osteoporosis in a national sample of the U.S. elderly population.
Design
Population‐based cross‐sectional study.
Setting
...Four‐year National Health and Nutrition Examination Survey data from two survey cycles between 2005–06 and 2007–08.
Participants
Men and women aged 50 and older with data in the surveys and medical examination data files (N = 5,288).
Measurements
Osteoporosis diagnosis was based on bone mineral density measurement and self‐report. Sleep duration was ascertained from the sleep survey. Simple and multiple logistic regression models were used to evaluate the association between these two factors.
Results
Shorter sleep duration (<6 hours) was found to be significantly associated with osteoporosis after adjusting for potential covariates (odds ratio (OR) = 1.59, 95% confidence interval (CI) = 1.07–2.37). After stratifying according to age group, this association remained significant (OR = 1.80, 95% CI = 1.20–2.68) only in the older age group (>65).
Conclusion
These results underscore the possible linkage between sleep and osteoporosis and the need for additional research on this topic.
In the Advanced Virgo+ interferometric gravitational-wave detector, the length control of the Fabry-Pérot cavities in the arms and of the detuned filter cavity, used for generating ...frequency-dependent squeezing, uses an auxiliary green beam at half of the operation laser wavelength (1064 nm). While operating the filter cavity with such a bichromatic control scheme for tens of hours, we observed that the mirror reflection phase shift of the fields at the two wavelengths responds differently to temperature changes in the mirrors, causing a change in the relative resonance condition of the two beams. In this paper we show that this thermal detuning effect can be explained by considering the thermomechanical properties of the mirror coating. Our experimental measurements are in good agreement with the theoretical predictions and allow us to drive requirements on the bicolor coating design and mirror temperature stability for long-term stable cavity control.
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