Using data from the 1991 Peru Demographic Health Survey, a linked Situation Analysis, and a unique region-level data set, this paper examines the determinants of fertility in rural Peru before and ...after the 1985 enactment of its National Policy on Population. The empirical framework combines a model of the timing and spacing of conceptions with a model of the timing of the placement of family planning services in communities in order to control for non-random placement of services. Results show the program helped reduce fertility post 1985. The magnitude of the effects is quantified with simulations.
The direct search for dark matter in the form of weakly interacting massive particles (WIMP) is performed by detecting nuclear recoils produced in a target material from the WIMP elastic scattering. ...The experimental identification of the direction of the WIMP-induced nuclear recoils is a crucial asset in this field, as it enables unmistakable modulation signatures for dark matter. The Recoil Directionality (ReD) experiment was designed to probe for such directional sensitivity in argon dual-phase time projection chambers (TPC), that are widely considered for current and future direct dark matter searches. The TPC of ReD was irradiated with neutrons at the INFN Laboratori Nazionali del Sud. Data were taken with nuclear recoils of known directions and kinetic energy of 72 keV, which is within the range of interest for WIMP-induced signals in argon. The direction-dependent liquid argon charge recombination model by Cataudella et al. was adopted and a likelihood statistical analysis was performed, which gave no indications of significant dependence of the detector response to the recoil direction. The aspect ratio
R
of the initial ionization cloud is
R
<
1.072
with 90 % confidence level.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The activation of materials due to exposure to cosmic rays may become an important background source for experiments investigating rare event phenomena. DarkSide-20k, currently under construction at ...the Laboratori Nazionali del Gran Sasso, is a direct detection experiment for galactic dark matter particles, using a two-phase liquid-argon Time Projection Chamber (TPC) filled with 49.7 tonnes (active mass) of Underground Argon (UAr) depleted in 39Ar. Despite the outstanding capability of discriminating γ/β background in argon TPCs, this background must be considered because of induced dead time or accidental coincidences mimicking dark-matter signals and it is relevant for low-threshold electron-counting measurements. Here, the cosmogenic activity of relevant long-lived radioisotopes induced in the experiment has been estimated to set requirements and procedures during preparation of the experiment and to check that it is not dominant over primordial radioactivity; particular attention has been paid to the activation of the 120 t of UAr used in DarkSide-20k. Expected exposures above ground and production rates, either measured or calculated, have been considered in detail. From the simulated counting rates in the detector due to cosmogenic isotopes, it is concluded that activation in copper and stainless steel is not problematic. The activity of 39Ar induced during extraction, purification and transport on surface is evaluated to be 2.8% of the activity measured in UAr by DarkSide-50 experiment, which used the same underground source, and thus considered acceptable. Other isotopes in the UAr such as 37Ar and 3H are shown not to be relevant due to short half-life and assumed purification methods.
Aria is a plant hosting a
350
m
cryogenic isotopic distillation column, the tallest ever built, which is being installed in a mine shaft at Carbosulcis S.p.A., Nuraxi-Figus (SU), Italy. Aria is one ...of the pillars of the argon dark-matter search experimental program, lead by the Global Argon Dark Matter Collaboration. It was designed to reduce the isotopic abundance of
39
Ar
in argon extracted from underground sources, called Underground Argon (UAr), which is used for dark-matter searches. Indeed,
39
Ar
is a
β
-emitter of cosmogenic origin, whose activity poses background and pile-up concerns in the detectors. In this paper, we discuss the requirements, design, construction, tests, and projected performance of the plant for the isotopic cryogenic distillation of argon. We also present the successful results of the isotopic cryogenic distillation of nitrogen with a prototype plant.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Future liquid-argon DarkSide-20k and Argo detectors, designed for direct dark matter search, will be sensitive also to core-collapse supernova neutrinos, via coherent elastic ...neutrino-nucleus scattering. This interaction channel is flavor-insensitive with a high-cross section, enabling for a high-statistics neutrino detection with target masses of ∼50 t and ∼360 t for DarkSide-20k and Argo respectively.
Thanks to the low-energy threshold of ∼0.5 keV
nr
achievable by exploiting the ionization channel, DarkSide-20k and Argo have the potential to discover supernova bursts throughout our galaxy and up to the Small Magellanic Cloud, respectively, assuming a 11-M
☉
progenitor star. We report also on the sensitivity to the neutronization burst, whose electron neutrino flux is suppressed by oscillations when detected via charged current and elastic scattering. Finally, the accuracies in the reconstruction of the average and total neutrino energy in the different phases of the supernova burst, as well as its time profile, are also discussed, taking into account the expected background and the detector response.
Using data from the Russia Longitudinal Monitoring Survey, we provide information regarding changes in individual and household economic indicators, as well as alcohol consumption and nutritional ...status in Russia during 1992–1996. During this period, there have been declines in income and expenditure, and substantial increases in the prevalence of poverty. At the same time, per capita alcohol consumption has risen significantly, as has the prevalence of obesity. We discuss the significance of these findings within the context of the current mortality crisis in Russia.
This paper examines the gender gap in wages in Russia from 1992 to 1995. It uses data on prime aged men and women from the Russia Longitudinal Monitoring Survey (RLMS) and focuses on those living in ...urban areas. Differences in hours of work appear to explain about one half of the gender differential, but there is still a large differential in average hourly wages between men and women. Observable differences in characteristics between men and women explain almost none of the differential or the changes through time.
This paper presents results of super(131)I thyroid activity measurements in 30 members of the nuclear medicine personnel of the Department of Endocrinology and Nuclear Medicine Holy Cross Cancer ...Centre in Kielce, Poland. A whole-body spectrometer equipped with two semiconductor gamma radiation detectors served as the basic research instrument. In ten out of 30 examined staff members, the determined super(131)I activity was found to be above the detection limit (DL = 5 Bq of super(131)I in the thyroid). The measured activities ranged from (5 plus or minus 2) Bq to (217 plus or minus 56) Bq. The highest activities in thyroids were detected for technical and cleaning personnel, whereas the lowest values were recorded for medical doctors. Having measured the activities, an attempt has been made to estimate the corresponding annual effective doses, which were found to range from 0.02 to 0.8 mSv. The highest annual equivalent doses have been found for thyroid, ranging from 0.4 to 15.4 mSv, detected for a cleaner and a technician, respectively. The maximum estimated effective dose corresponds to 32% of the annual background dose in Poland, and to circa 4% of the annual limit for the effective dose due to occupational exposure of 20 mSv per year, which is in compliance with the value recommended by the International Commission on Radiological Protection.
This paper presents results of 131I thyroid activity measurements in 30 members of the nuclear medicine personnel of the Department of Endocrinology and Nuclear Medicine Holy Cross Cancer Centre in ...Kielce, Poland. A whole-body spectrometer equipped with two semiconductor gamma radiation detectors served as the basic research instrument. In ten out of 30 examined staff members, the determined 131I activity was found to be above the detection limit (DL = 5 Bq of 131I in the thyroid). The measured activities ranged from (5 ± 2) Bq to (217 ± 56) Bq. The highest activities in thyroids were detected for technical and cleaning personnel, whereas the lowest values were recorded for medical doctors. Having measured the activities, an attempt has been made to estimate the corresponding annual effective doses, which were found to range from 0.02 to 0.8 mSv. The highest annual equivalent doses have been found for thyroid, ranging from 0.4 to 15.4 mSv, detected for a cleaner and a technician, respectively. The maximum estimated effective dose corresponds to 32% of the annual background dose in Poland, and to circa 4% of the annual limit for the effective dose due to occupational exposure of 20 mSv per year, which is in compliance with the value recommended by the International Commission on Radiological Protection.
Poor sleep is associated with negative health outcomes among older adults, yet little is known about napping in this population and research has not distinguished between planned and spontaneous ...naps, or duration. This study examines napping using a retrospective cohort of Medicare beneficiaries >65 years of age enrolled in year four of National Health and Aging Trends Study who reported regular napping (n=1,016). Regressions examined the relationships between sociodemographic and clinical characteristics and napping outcomes, specifically unplanned or extended (i.e., >60 minutes) naps. Survey weighting was used for all analyses.
Among Medicare beneficiaries who nap, 58.7% reported unplanned naps and 18.5% regularly take extended naps. Unplanned napping was associated with older age, non-white race, non-married status, poorer self-reported health, and shorter nighttime sleep duration. For example, individuals 75–84 years of age had 2.1 higher odds of unplanned naps compared to those aged 65–74. Male sex, poorer self-reported health, and a greater number of chronic conditions were associated with higher odds of extended naps. Those with the worst self-reported health were 2.8 times more likely to take long naps than those reporting the best health. Pain and depression were not associated with either outcome.
We found that ~4.3 million older adults in the U.S. regularly nap without meaning to, and ~1.4 million individuals routinely took extended naps. Furthermore, different constellations of risk factors are associated with unplanned and extended napping. Research examining the impact of unplanned and extended napping is warranted to optimize sleep and other health outcomes.
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