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The COSINE-100 dark matter search experiment is an array of NaI(Tl) crystal detectors located in the Yangyang Underground Laboratory (Y2L). To understand measured backgrounds in the NaI(Tl) crystals we have performed Monte Carlo simulations using the Geant4 toolkit and developed background models for each crystal that consider contributions from both internal and external sources, including cosmogenic nuclides. The background models are based on comparisons of measurement data with Monte Carlo simulations that are guided by a campaign of material assays and are used to evaluate backgrounds and identify their sources. The average background level for the six crystals (70 kg total mass) that are studied is 3.5 counts/day/keV/kg in the (2-6) keV energy interval. The dominant contributors in this energy region are found to be 210 Pb and 3 H.

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Safflower (Carthamus tinctorius L.) seeds have long been clinically used in Korea to promote bone formation and prevent osteoporosis. However, the beneficial effect has not been scientifically evaluated. Thus, in the present study we investigated whether phytoestrogen rich safflower seeds reduce bone loss in ovariectomized rats. Female Sprague-Dawley rats were subjected to bilateral ovariectomy or sham surgery. One week after the operation, ovariectomized rats were either fed a diet containing defatted safflower seeds or injected with 17b-estradiol (E2) for 4 weeks. As expected, ovariectomy resulted in a dramatic reduction in trabecular bone mass of the proximal tibia, increase in deposition of marrow fat, and in uterine atrophy. E2 treatment almost completely prevented bone loss as well as marrow adiposity, as examined by scanning electron microscopy and histomorphometry. Safflower seeds partially prevented ovariectomy-induced bone loss and slightly reduced marrow adiposity. Safflower seeds, in contrast to E2, exerted very weak uterotrophic action. In an attempt to elucidate the underlying mechanisms, effect of polyphenolic compounds extracted from safflower seeds on proliferation of osteoblast-like cells was also assessed in vitro. The mixed polyphenolic compounds stimulated growth of ROS 17/2.8 osteoblast-like cells in a dose-dependent manner (5-100 mg/ml), as potently as E2 and genistein. The present data provide the first direct in vivo evidence that safflower seeds have a protecting effect on bone loss caused by estrogen deficiency, without substantial effect on the uterus. The beneficial effect of safflower seeds may be mediated, at least in part, by the stimulating effect of polyphenolic compounds on proliferation of osteoblasts.

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There is a long standing debate about whether or not the annual modulation signal reported by the DAMA/LIBRA collaboration is induced by Weakly Interacting Massive Particles (WIMP) in the galaxy's dark matter halo scattering from nuclides in their NaI(Tl) crystal target/detector. This is because regions of WIMP-mass vs. WIMP-nucleon crosssection parameter space that can accommodate the DAMA/LIBRA-phase1 modulation signal in the context of the standard WIMP dark matter galactic halo and isospin-conserving (canonical), spin-independent (SI) WIMP-nucleon interactions have been excluded by many of other dark matter search experiments including COSINE-100, which uses the same NaI(Tl) target/detector material. Moreover, the recently released DAMA/LIBRA-phase2 results are inconsistent with an interpretation as WIMP-nuclide scattering via the canonical SI interaction and prefer, instead, isospin-violating or spin-dependent interactions. Dark matter interpretations of the DAMA/LIBRA signal are sensitive to the NaI(Tl) scintillation efficiency for nuclear recoils, which is characterized by so-called quenching factors (QF), and the QF values used in previous studies differ significantly from recently reported measurements, which may have led to incorrect interpretations of the DAMA/LIBRA signal. In this article, the compatibility of the DAMA/LIBRA and COSINE-100 results, in light of the new QF measurements is examined for different possible types of WIMP-nucleon interactions. The resulting allowed parameter space regions associated with the DAMA/LIBRA signal are explicitly compared with 90% confidence level upper limits from the initial 59.5 day COSINE-100 exposure. With the newly measured QF values, the allowed 3σ regions from the DAMA/LIBRA data are still generally excluded by the COSINE-100 data.