3,057 research outputs found
Time-dependent gravity in southern California, May 1974 - Apr 1979
Gravity measurements were coordinated with the long baseline three dimensional geodetic measurements of the Astronomical Radio Interferometric Earth Surveying project which used radio interferometry with extra-galactic radio sources. Gravity data from 28 of the stations had a single reading standard deviation of 11 microgal which gives a relative single determination between stations a standard deviation of 16 microgal. The largest gravity variation observed, 80 microgal, correlated with nearby waterwell variations and with smoothed rainfall. Smoothed rainfall data appeared to be a good indicator of the qualitative response of gravity to changing groundwater levels at other suprasediment stations, but frequent measurement of gravity at a station was essential until the quantitative calibration of the station's response to groundwater variations was accomplished
Stress Buffer or Identity Threat?: Negative Media Portrayal, Public and Private Religious Involvement, and Mental Health in a National Sample of US Adults
Guided by the stress process tradition, complex links between religion and mental health have received growing attention from researchers. This study gauges individualsâ public and private religiosity, uses a novel measure of environmental stressânegative media portrayal of religionâand presents two divergent hypotheses: (1) religiosity as stress-exacerbating attachment to valued identities producing mental health vulnerability to threat and (2) religiosity as stress-buffering social psychological resource. To assess these hypotheses, we analyze three mental health outcomes (generalized anxiety, social anxiety, and general mental health problems) in national U.S. data from 2010 (N = 1,714). Our findings align with the stress-buffering perspective. Results show that individuals low in public and private religiosity tend to have worse mental health with greater negative media portrayal. High public or private religiosity tends to nullify the relationship between negative media portrayal and mental health
Fluctuations of prolonged grief disorder reactions in the daily life of bereaved people:An experience sampling study
IntroductionLoss-adaptation has been described as being characterized by âwaves of griefâ, whichmay result in a Prolonged Grief Disorder (PGD). Although this assumption about thefluctuating nature of grief is supported by theoretical work, it is not (yet) supported byempirical work. We are the first to explore to what extent PGD reactions fluctuate ineveryday life and whether fluctuations in PGD reactions are related to overall PGDlevels using experience sampling methodology (ESM).MethodsData from 38 bereaved individuals (74% women, on average 6 years post-loss, 47%lost a parent) were analyzed. For two weeks, five times per day, participants reportedon the severity of 11 PGD reactions in the past three hours (ESM-PGD). At baseline,overall PGD severity (B-PGD) in the past two weeks was assessed with telephone interviews using the Traumatic Grief InventoryâClinician Administered. Root MeanSquare of Successive Differences (RMSSD) were calculated to reflect fluctuations inESM-PGD. Spearman correlations between RMSSD values of the 11 ESM-PGDreactions and B-PGD scores were computed.ResultsMean B-PGD scores were below the clinical cut-off. Some fluctuations in ESM-PGDreactions were found, as indicated by varying RMSSD values, but also floor effectswere detected. B-PGD levels were related to RMSSD values for ESM-PGD (Ï between.37 and .68, all p < .05; and between .36 and .63 after removal of floor effects).DiscussionWe found that (some) ESM-PGD reactions fluctuated in everyday life. This may offernew theoretical insights into loss-adaptation, which may result in optimizing PGDtreatment
Squeezed-field injection for gravitational wave interferometers
In a recent table-top experiment, we demonstrated the compatibility of three advanced interferometer techniques for gravitational wave detection, namely power-recycling, detuned signal recycling and squeezed-field injection. The interferometer's signal-to-noise ratio was improved by up to 2.8 dB beyond the coherent state's shot-noise. This value was mainly limited by optical losses on the squeezed field. We present a detailed analysis of the optical losses in our experiment and provide an estimation of the possible nonclassical performance of a future squeezed-field enhanced GEO 600 detector
Squeezed light at sideband frequencies below 100 kHz from a single OPA
Quantum noise of the electromagnetic field is one of the limiting noise
sources in interferometric gravitational wave detectors. Shifting the spectrum
of squeezed vacuum states downwards into the acoustic band of gravitational
wave detectors is therefore of challenging demand to quantum optics
experiments. We demonstrate a system that produces nonclassical continuous
variable states of light that are squeezed at sideband frequencies below 100
kHz. A single optical parametric amplifier (OPA) is used in an optical noise
cancellation scheme providing squeezed vacuum states with coherent bright phase
modulation sidebands at higher frequencies. The system has been stably locked
for half an hour limited by thermal stability of our laboratory.Comment: 3 pages, 3 figure
High quality anti-relaxation coating material for alkali atom vapor cells
We present an experimental investigation of alkali atom vapor cells coated
with a high quality anti-relaxation coating material based on alkenes. The
prepared cells with single compound alkene based coating showed the longest
spin relaxation times which have been measured up to now with room temperature
vapor cells. Suggestions are made that chemical binding of a cesium atom and an
alkene molecule by attack to the C=C bond plays a crucial role in such
improvement of anti-relaxation coating quality
On the distillation and purification of phase-diffused squeezed states
Recently it was discovered that non-Gaussian decoherence processes, such as
phase-diffusion, can be counteracted by purification and distillation protocols
that are solely built on Gaussian operations. Here, we make use of this
experimentally highly accessible regime, and provide a detailed experimental
and theoretical analysis of several strategies for purification/distillation
protocols on phase-diffused squeezed states. Our results provide valuable
information for the optimization of such protocols with respect to the choice
of the trigger quadrature, the trigger threshold value and the probability of
generating a distilled state
- âŠ