23 research outputs found

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    A review of mixed-potential type zirconia-based gas sensors

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    Intravenous magnesium sulfate for the management of severe hand, foot, and mouth disease with autonomic nervous system dysregulation in Vietnamese children: study protocol for a randomized controlled trial

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    Over the last 15 years, hand, foot, and mouth disease (HFMD) has emerged as a major public health burden across the Asia-Pacific region. A small proportion of HFMD patients, typically those infected with enterovirus 71 (EV71), develop brainstem encephalitis with autonomic nervous system (ANS) dysregulation and may progress rapidly to cardiopulmonary failure and death. Although milrinone has been reported to control hypertension and support myocardial function in two small studies, in practice, a number of children still deteriorate despite this treatment. Magnesium sulfate (MgSO4) is a cheap, safe, and readily available medication that is effective in managing tetanus-associated ANS dysregulation and has shown promise when used empirically in EV71-confirmed severe HFMD cases.We describe the protocol for a randomized, placebo-controlled, double-blind trial of intravenous MgSO4 in Vietnamese children diagnosed clinically with HFMD plus ANS dysregulation with systemic hypertension. A loading dose of MgSO4 or identical placebo is given over 20 min followed by a maintenance infusion for 72 h according to response, aiming for Mg levels two to three times the normal level in the treatment arm. The primary endpoint is a composite of disease progression within 72 h defined as follows: development of pre-specified blood pressure criteria necessitating the addition of milrinone, the need for ventilation, shock, or death. Secondary endpoints comprise these parameters singly, plus other clinical endpoints including the following: requirement for other inotropic agents; duration of hospitalization; presence of neurological sequelae at discharge in survivors; and neurodevelopmental status assessed 6 months after discharge. The number and severity of adverse events observed in the two treatment arms will also be compared. Based on preliminary data from a case series, and allowing for some losses, 190 patients (95 in each arm) will allow detection of a 50 % reduction in disease progression with 90 % power at a two-sided 5 % significance level.Given the large numbers of HFMD cases currently being seen in hospitals in Asia, if MgSO4 is shown to be effective in controlling ANS dysregulation and preventing severe HFMD complications, this finding would be important to pediatric care throughout the region.ClinicalTrials.gov Identifier: NCT01940250 (Registered 22 August 2013)

    The energy expenditure at critically ill patients

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    The aim of this study was to determine energy expenditure and to find relations between resting energy expenditure (REE) and selected parameters in 14 polytraumatic patients in the ICU of University Hospital in Hradec Kralove, which were easily measurable and usable for REE prediction. In this study 7 men (age 36 ± 18 years) and 7 women (age 58 ± 28 years) with polytrauma were examined. The assessment of REE was measured via indirect calorimetry (IC) method. The examination also included bioimpedance analysis (BIA). BIA was useful especially for obtaining values of overhydration (OH), lean tissue mass (LTM) and metabolically active body cell mass (BCM). Average REE-IC (measured by IC) was 2116 ± 516 kcal·day-1 in men and 1450 ± 407 kcal·day-1 in women (P = 0.018). Statistically significant difference between men's and women's population was also found in these relations: calculation of basal energy expenditure according to Harris-Bennedict equation without (P = 0.001) and with deduction of OH from body weight (P = 0.001), at "breathing energy expenditure" (REE related to respiratory rate) (P = 0.018) and at (REE related to heart rate) "heart rate energy expenditure" (P = 0.038). REE-IC related to kilogram of BCM with and without deduction of overhydration was shown as statistically significant..

    Oral health status of Vietnamese children: Findings from the National Oral Health Survey of Vietnam 1999

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    The National Oral Health Survey of Vietnam 1999 was conducted to inform policy development. Aims. The aims were to describe the oral health status, to analyze its socioeconomic distribution, and to evaluate change over time in the oral health of Vietnamese children. Methods. A multistaged stratified sampling process was employed. Children aged 6 to 17 years were examined by trained and calibrated dental examiners. A parental questionnaire was used. Drinking water was analyzed. Results. Preventive oral health behaviors and dental care utilization were infrequent. The decayed, missing, and filled surfaces referring to primary dentition (dmfs) and permanent dentition (DMFS) scores (SD) were 8.9 (11.3) and 2.5 (4.4), respectively. Primary caries experience was associated with fluoride level in drinking water, age, gender, residential status, and geographical location. Permanent caries was also associated with dental visiting and parental education. There was an increase in the prevalence of dental caries in the Vietnamese child population compared with 10 years earlier. Conclusion. The oral health of Vietnamese children was characterized by high level of dental caries with variation among socioeconomic groups. It suggests the need for a population oral health program that includes measures to target high-need children.Loc Giang Do, Andrew John Spencer, Kaye Frances Roberts-Thomson, Hai Dinh Trinh and Thuy Thanh Nguye
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