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1.
Phys Rev Lett ; 123(3): 031302, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31386435

RESUMO

We present new constraints on the dark matter-induced annual modulation signal using 1.7 years of COSINE-100 data with a total exposure of 97.7 kg yr. The COSINE-100 experiment, consisting of 106 kg of NaI(Tl) target material, is designed to carry out a model-independent test of DAMA/LIBRA's claim of WIMP discovery by searching for the same annual modulation signal using the same NaI(Tl) target. The crystal data show a 2.7 cpd/kg/keV background rate on average in the 2-6 keV energy region of interest. Using a χ-squared minimization method we observe best fit values for modulation amplitude and phase of 0.0092±0.0067 cpd/kg/keV and 127.2±45.9 d, respectively.

2.
Phys Rev Lett ; 122(13): 131802, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31012610

RESUMO

A search for inelastic boosted dark matter (IBDM) using the COSINE-100 detector with 59.5 days of data is presented. This relativistic dark matter is theorized to interact with the target material through inelastic scattering with electrons, creating a heavier state that subsequently produces standard model particles, such as an electron-positron pair. In this study, we search for this electron-positron pair in coincidence with the initially scattered electron as a signature for an IBDM interaction. No excess over the predicted background event rate is observed. Therefore, we present limits on IBDM interactions under various hypotheses, one of which allows us to explore an area of the dark photon parameter space that has not yet been covered by other experiments. This is the first experimental search for IBDM using a terrestrial detector.

3.
Eur Phys J C Part Fields ; 78(6): 490, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30956554

RESUMO

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.

4.
Bull. W.H.O. (Online) ; 88(12): 897-906, 2010.
Artigo em Inglês | AIM (África) | ID: biblio-1259857

RESUMO

Objective To study paediatric surgery rates in south-western Uganda; compare them to rates in England; and determine if existing surgical facilities and workforce meet World Health Organization (WHO) standards. Methods To obtain information on surgical facilities and workforce; we conducted a cross-sectional survey of all hospitals performing major surgery in 14 districts of south-western Uganda in 2007.2008. Using theatre logbook data; we determined the surgical rates; types of surgery performed and in-theatre surgical outcomes. Findings Of 72 hospitals surveyed; 29 were performing major surgery. None met WHO standards for essential surgery. There were 0.7 accredited surgeons per 100 000 population and no paediatric surgeons. Most anaesthetists were not physicians (accredited anaesthetist per 100 000 population: 1.1).The annual surgical rate for children aged . 14 years was 180 operations per 100 000 population; most were emergency procedures. The annual surgical rate for patients of all ages was 652 operations per 100 000 population; with a median of 422 per operating theatre (range: 60.3497) and of 226 per surgeon (range: 60.1748). Mission or nongovernmental organization (NGO) hospitals; which had 44of the hospital beds in the region; performed 3039 (55) of the paediatric operations. Externally funded surgeons performed 80of the 140 cleft lip and palate operations. Four in-theatre deaths occurred in children . 14 years old (in-theatre mortality: 7.7 deaths per 10 000 operations). Conclusion Access to all surgery; including paediatric surgery; is poor in south-western Uganda and investment in basic health-care facilities and surgical workforce and training is urgently needed. Mission and NGO hospitals make a valuable contribution to elective surgery; and externally funded surgeons make an important contribution to specialist surgery. In-theatre mortality was lower than reported for similar settings


Assuntos
Estudos Transversais , Pediatria , Procedimentos Cirúrgicos Operatórios
5.
Ann Endocrinol (Paris) ; 69(3): 244-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18486933

RESUMO

TSH-secreting adenomas are rare tumors, representing only 0.5 to 2.5% of pituitary adenomas. Their main clinical characteristics include signs of thyrotoxicosis, diffuse goiter and a compressive syndrome. Biologically, free T4 and T3 serum levels are elevated, contrasting with inadequate serum TSH levels and increased alpha chains. Magnetic resonance (MR) imaging shows a pituitary tumor, the main differential diagnosis being resistance to thyroid hormones. Treatment is based on surgery, possibly associated with somatostatin analogs and radiotherapy. Though the long-term evolution of this rare pathology seems to have improved, some clinical situations are still a challenge to treat. We report one such case that was resistant to both stereotactic radiotherapy and somatostatin analogs, but surprisingly improved with cabergoline. We suggest that cabergoline should be considered as an alternative treatment in cases of pituitary adenomas that resist traditional treatments.


Assuntos
Antineoplásicos/uso terapêutico , Ergolinas/uso terapêutico , Neoplasias Hipofisárias/tratamento farmacológico , Neoplasias Hipofisárias/metabolismo , Tireotropina/metabolismo , Adulto , Osso e Ossos/anormalidades , Osso e Ossos/patologia , Cabergolina , Humanos , Masculino , Neoplasias Hipofisárias/sangue , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
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