98 research outputs found

    C. elegans EIF-3.K Promotes Programmed Cell Death through CED-3 Caspase

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    Programmed cell death (apoptosis) is essential for the development and homeostasis of metazoans. The central step in the execution of programmed cell death is the activation of caspases. In C. elegans, the core cell death regulators EGL-1(a BH3 domain-containing protein), CED-9 (Bcl-2), and CED-4 (Apaf-1) act in an inhibitory cascade to activate the CED-3 caspase. Here we have identified an additional component eif-3.K (eukaryotic translation initiation factor 3 subunit k) that acts upstream of ced-3 to promote programmed cell death. The loss of eif-3.K reduced cell deaths in both somatic and germ cells, whereas the overexpression of eif-3.K resulted in a slight but significant increase in cell death. Using a cell-specific promoter, we show that eif-3.K promotes cell death in a cell-autonomous manner. In addition, the loss of eif-3.K significantly suppressed cell death-induced through the overexpression of ced-4, but not ced-3, indicating a distinct requirement for eif-3.K in apoptosis. Reciprocally, a loss of ced-3 suppressed cell death induced by the overexpression of eif-3.K. These results indicate that eif-3.K requires ced-3 to promote programmed cell death and that eif-3.K acts upstream of ced-3 to promote this process. The EIF-3.K protein is ubiquitously expressed in embryos and larvae and localizes to the cytoplasm. A structure-function analysis revealed that the 61 amino acid long WH domain of EIF-3.K, potentially involved in protein-DNA/RNA interactions, is both necessary and sufficient for the cell death-promoting activity of EIF-3.K. Because human eIF3k was able to partially substitute for C. elegans eif-3.K in the promotion of cell death, this WH domain-dependent EIF-3.K-mediated cell death process has potentially been conserved throughout evolution

    Ultrasound-assisted extraction of natural products

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    Ultrasound-assisted extraction (USAE) is an interesting process to obtain high valuable compounds and could contribute to the increase in the value of some food by-products when used as sources of natural compounds. The main benefits will be a more effective extraction, thus saving energy, and also the use of moderate temperatures, which is beneficial for heat-sensitive compounds. For a successful application of the USAE, it is necessary to consider the influence of several process variables, the main ones being the applied ultrasonic power, the frequency, the extraction temperature, the reactor characteristics, and the solvent-sample interaction. The highest extraction rate is usually achieved in the first few minutes, which is the most profitable period. To optimize the process, rate equations and unambiguous process characterization are needed, aspects that have often been lacking. © 2011 Springer Science+Business Media, LLC.The authors thank the Generalitat Valenciana for their financial support in project PROMETEO/2010/062 and the Caja de Ahorros del Mediterraneo for M.D. Esclapez's pre-doctoral grant.Esclapez Vicente, MD.; García Pérez, JV.; Mulet Pons, A.; Cárcel Carrión, JA.; Esclapez, MD. (2011). Ultrasound-assisted extraction of natural products. Food Engineering Reviews. 3(2):108-120. https://doi.org/10.1007/s12393-011-9036-6S10812032Abad Romero B, Bou-Maroun E, Reparet JM, Blanquet J, Cayot N (2010) Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder. Food Chem 119:459–466Adewuyi YG (2001) Sonochemistry: environmental science and engineering applications. Ind Eng Chem Res 40:4681–4715Atchley AA, Crum LA (1988) Acoustic cavitation and bubble dynamics. In: Suslick KS (ed) Ultrasound, its chemical, physical, and biological effects. VHS Publishers, Weinheim, pp 1–64Arnold G, Leiteritz L, Zahn S, Rohm H (2009) Ultrasonic cutting of cheese: composition affects cutting work reduction and energy demand. Int Dairy J 19:314–320Barbero GF, Liazid A, Palma M, Barroso CG (2008) Ultrasound-assisted extraction of capsaicinoids from peppers. Talanta 75:1332–1337Benedito J, Carcel JA, Sanjuan N, Mulet A (2000) Use of ultrasound to assess Cheddar cheese characteristics. Ultrasonics 38:727–730Benedito J, Carcel JA, Rossello C, Mulet A (2001) Composition assessment of raw meat mixtures using ultrasonics. Meat Sci 57:365–370Bhaskaracharya RK, Kentish S, Ashokkumar M (2009) Selected applications of ultrasonics in food processing. Food Eng Rev 1:31–49Boonkird S, Phisalaphong C, Phisalaphong M (2008) Ultrasound-assisted extraction of capsaicinoids from Capsicum frutescens on a lab- and pilot-plant scale. Ultrason Sonochem 15:1075–1079Cárcel JA, Benedito J, Bon J, Mulet A (2007) High intensity ultrasound effects on meat brining. Meat Sci 76:611–619Cárcel JA, Benedito J, Rosselló C, Mulet A (2007) Influence of ultrasound intensity on mass transfer in apple immersed in a sucrose solution. J Food Eng 78:472–479Cavitus (2009) Grape colour and flavour extraction (Pat. Pend.) for red must extraction http://www.cavitus.com . Crafers. Accessed 10 Jan 2011Chea Chua S, Ping Tan C, Mirhosseini H, Ming Lai O, Long K, Sham Baharin B (2009) Optimization of ultrasound extraction condition of phospholipids from palm-pressed fiber. J Food Eng 92:403–409Chena R, Menga F, Zhang S, Liu Z (2009) Effects of ultrahigh pressure extraction conditions on yields and antioxidant activity of ginsenoside from ginseng. Sep Purif Technol 66:340–346Chivate MM, Pandit AB (1995) Quantification of cavitation intensity in fluid bulk. Ultrason Sonochem 2:19–25Da Porto C, Decorti D (2009) Ultrasound-assisted extraction coupled with under vacuum distillation of flavour compounds from spearmint (carvone-rich) plants: comparison with conventional hydrodistillation. Ultrason Sonochem 16:795–799Da Porto C, Decorti D, Kikic I (2009) Flavour compounds of Lavandula angustifolia L. to use in food manufacturing: Comparison of three different extraction methods. Food Chem 112:1072–1078Domínguez H, Núñez MJ, Lema JM (1994) Enzymatic pretreatment to enhance oil extraction from fruits and oilseeds: a review. Food Chem 49:271–286Dong J, Liu Y, Liang Z, Wanga W (2010) Investigation on ultrasound-assisted extraction of salvianolic acid B from Salvia miltiorrhiza root. Ultrason Sonochem 17:61–65Entezari MH, Kruus P (1994) Effect of frequency on sonochemical reactions. I: oxidation of iodide. Ultrason Sonochem 1:75–79Esclapez MD, Sáez V, Milán-Yáñez D, Tudela I, Louisnard O, González-García J (2010) Sonoelectrochemical treatment of water polluted with trichloroacetic acid: from sonovoltammetry to pre-pilot plant scale. Ultrason Sonochem 17:1010–1020Ferraro V, Cruz IB, Ferreira R, Malcata JFX, Pintado ME, Castro PML (2010) Valorisation of natural extracts from marine source focused on marine by-products: review. Food Res Int 43:2221–2233Fischer CH, Hart EJ, Henglein AJ (1986) Hydrogen/deuterium isotope exchange in the hydrogen deuteride-water system under the influence of ultrasound. Phys Chem 90:3059–3060Garcia-Noguera J, Weller CL, Oliveira FIP, Rodrigues S, Fernandes FAN (2010) Dual-stage sugar substitution in strawberries with a Stevia-based sweetener. Innovative Food Sci Emerg Technol 11:225–230García-Pérez JV, Cárcel JA, de la Fuente-Blanco S, Riera-Franco de Sarabia E (2006) Ultrasonic drying of foodstuff in a fluidized bed: parametric study. Ultrasonics 44:539–543García-Pérez JV, García-Alvarado MA, Carcel JA, Mulet A (2010) Extraction kinetics modeling of antioxidants from grape stalk (Vitis vinifera var. Bobal): Influence of drying conditions. J Food Eng 101:49–58González-García J, Sáez V, Tudela I, Díez-Garcia MI, Esclapez MD, Louisnard O (2010) Sonochemical treatment of water polluted by chlorinated organocompounds. A review. Water 2:28–74Handa SS, Preet S, Khanuja S, Longo G, Rakesh DD (2008) Extraction Technologies for Medicinal and Aromatic Plants. United Nations Industrial Development Organization and the International Centre for Science and High Technology, TriesteHemwimol S, Pavasant P, Shotipruk A (2006) Ultrasound-assisted extraction of anthraquinones from roots of Morinda citrifolia. Ultrason Sonochem 13:543–548Hielscher (2011) Teltow http:// www.hielscher.com . Accessed 10 Jan 2011Hu Y, Wang T, Wang M, Han S, Wan P, Fan M (2008) Extraction of isoflavonoids from Pueraria by combining ultrasound with microwave vacuum. Chem Engin Process 47:2256–2261Ince NH, Tezcanli G, Belen RK, Apikyan PG (2001) Ultrasound as a catalyzer of aqueous reaction systems: the state of the art and environmental applications. Appl Catal B 29:167–176Jadhav D, Rekha BN, Gogate PR, Rathod VK (2009) Extraction of vanillin from vanilla pods: a comparison study of conventional soxhlet and ultrasound assisted extraction. J Food Eng 93:421–426Ji J-b, Lu X-h, Cai M-q, Xu C-c (2006) Improvement of leaching process of Geniposide with ultrasound. Ultrason Sonochem 13:455–462Kanthale PM, Gogate PR, Pandit AB, Wilhelm AM (2003) Mapping of an ultrasonic horn: link primary and secondary effects of ultrasound. Ultrason Sonochem 10:331–335Karki B, Lamsal BP, Jung S, van Leeuwen JH, Pometto AL III, Grewell D, Khanal SK (2010) Enhancing protein and sugar release from defatted soy flakes using ultrasound technology. J Food Eng 96:270–278Kardos N, Luche J-L (2001) Sonochemistry of carbohydrate compounds. Carbohydr Res 332:115–131Kotronarou A, Mills G, Hoffmann MR (1991) Ultrasonic Irradiation of para-Nitrophenol in Aqueous Solution. J Phys Chem 95:3630–3638Kuijpers MWA, Kemmere MF, Keurentjes JTF (2002) Calorimetric study of the energy efficiency for ultrasound-induced radical formation. Ultrasonics 40:675–678Leighton TG (2007) What is ultrasound? Prog Biophys Mol Biol 93:3–83Leonelli C, Mason TJ (2010) Microwave and ultrasonic processing: now a realistic option for industry. Chem Eng Process 49:885–900Li H, Pordesimo L, Weiss J (2004) High intensity ultrasound-assisted extraction of oil from soybeans. Food Res Int 37:731–738Liu J, Li J-W, Tang J (2010) Ultrasonically assisted extraction of total carbohydrates from Stevia rebaudiana Bertoni and identification of extracts. Food Bioprod Process 88:215–221Lianfu Z, Zelong L (2008) Optimization and comparison of ultrasound/microwave assisted extraction (UMAE) and ultrasonic assisted extraction (UAE) of lycopene from tomatoes. Ultrason Sonochem 15:731–737Liazid A, Schwarz M, Varela RM, Palma M, Guillén DA, Brigui J, Macías FA, Barroso CG (2010) Evaluation of various extraction techniques for obtaining bioactive extracts from pine seeds. Food Bioprod Process 88:247–252Londoño-Londoño J, Rodrigues de Lima V, Lara O, Gil A, Crecsynski Pasa TB, Arango GJ, Ramirez Pineda JR (2010) Clean recovery of antioxidant flavonoids from citrus peel: optimizing an aqueous ultrasound-assisted extraction method. Food Chem 119:81–87Lou Z, Wang H, Zhang M, Wang Z (2010) Improved extraction of oil from chickpea under ultrasound in a dynamic system. J Food Eng 98:13–18Louisnard O, González-García J, Tudela I, Klima J, Sáez V, Vargas-Hernández Y (2009) FEM simulation of a sono-reactor accounting for vibrations of the boundaries. Ultrason Sonochem 16:250–259Luque de Castro MD, Priego-Capote F (2007) Analytical Applications of Ultrasound, Vol. 26, Techniques and Instrumentation in Analytical Chemistry. Elsevier Science, AmsterdamMa Y, Ye X, Hao Y, Xu G, Xu G, Liu D (2008) Ultrasound-assisted extraction of hesperidin from Penggan (Citrus reticulata) peel. Ultrason Sonochem 15:227–232Ma Y, Chen J-C, Liu Dong-Hong, Ye X-Q (2009) Simultaneous extraction of phenolic compounds of citrus peel extracts: effect of ultrasound. Ultrason Sonochem 16:57–62Makino K, Mossoba MM, Riesz P (1982) Chemical effects of ultrasound on aqueous solutions. Evidence for hydroxyl and hydrogen free radicals (.cntdot. OH and. cntdot. H) by spin trapping. J Chem Soc 104:3537–3539Margulis MA, Margulis IM (2003) Calorimetric method for measurement of acoustic power absorbed in a volume of liquid. Ultrason Sonochem 10:343–345Martin CJ, Law ANR (1983) Design of thermistor probes for measurement of ultrasound intensity distributions. Ultrasonics 21:85–90Mason TJ, Lorimer JP, Bates DM, Zhao Y (1994) Dosimetry in sonochemistry: the use of aqueous terephthalate ion as a fluorescence monitor. Ultrason Sonochem 1:91–95Meinhardt (2011) Leipzig. http://www.meinhardt-ultraschall.de . Accessed 10 Jan 2011Montalbo-Lomboy M, Khanal SK, van Leeuwen JH, Raman DR, Dunn L Jr, Grewell D Jr (2010) Ultrasonic pretreatment of corn slurry for saccharification: a comparison of batch and continuous Systems. Ultrason Sonochem 17:939–946Mulet A, Cárcel JA, Sanjuán N, Bon J (2003) New food drying technologies. Use of ultrasound. Food Sci Technol Int 9:215–221Naguleswaran S, Vasanthan T (2010) Dry milling of field pea (Pisum sativum L.) groats prior to wet fractionation influences the starch yield and purity. Food Chem 118:627–633Orozco-Solano M, Ruiz-Jiménez J, Luque de Castro MD (2010) Ultrasound-assisted extraction and derivatization of sterols and fatty alcohols from olive leaves and drupes prior to determination by gas chromatography–tandem mass spectrometry. J Chromatogr A 1217:1227–1235Patist A, Bates D (2008) Ultrasonic innovations in the food industry: from the laboratory to commercial production. Innovative Food Sci Emerg Technol 9:147–154Price GJ (1990) The use of ultrasound for the controlled degradation of polymer solutions. In: Mason TJ (ed) Advances in sonochemistry, vol 1. Jai Press, Cambridge, pp 231–287Riener J, Noci G, Cronin DA, Morgan DJ, Lyng JG (2010) A comparison of selected quality characteristics of yoghurts prepared from thermosonicated and conventionally heated milks. Food Chem 119:1108–1113Riera E, Golás Y, Blanco A, Gallego JA, Blasco M, Mulet A (2004) Mass transfer enhancement in supercritical fluids extraction by means of power ultrasound. Ultrason Sonochem 11:241–244Riera E, Blanco A, García J, Benedito J, Mulet A, Gallego-Juárez JA, Blasco M (2010) High-power ultrasonic system for the enhancement of mass transfer in supercritical CO2 extraction processes. Physics Procedia 3:141–146Roldán-Gutiérrez JM, Ruiz-Jiménez J, Luque de Castro MD (2008) Ultrasound-assisted dynamic extraction of valuable compounds from aromatic plants and flowers as compared with steam distillation and superheated liquid extraction. Talanta 75:1369–1375Romdhane M, Gourdon C (2002) Investigation in solid–liquid extraction: influence of ultrasound. Chem Eng J 87:11–19Rong L, Kojima Y, Koda S, Nomura H (2008) Simple quantification of ultrasonic intensity using aqueous solution of phenolphthalein. Ultrason Sonochem 8:11–15Sáez V, Frias-Ferrer A, Iniesta J, Gonzalez-Garcıa J, Aldaz A, Riera E (2005) Chacterization of a 20 kHz sonoreactor. Part I: analysis of mechanical effects by classical and numerical methods. Ultrason Sonochem 12:59–65Sáez V, Frias-Ferrer A, Iniesta J, Gonzalez-Garcıa J, Aldaz A, Riera E (2005) Characterization of a 20 kHz sonoreactor. Part II: analysis of chemical effects by classical and electrochemical methods. Ultrason Sonochem 12:67–72Sahena F, Zaidul ISM, Jinap S, Karim AA, Abbas KA, Norulaini NAN, Omar AKM (2009) Application of supercritical CO2 in lipid extraction–A review. J Food Eng 95:240–253Science Direct Database (2011) www.sciencedirect.com (Data of consulting: February 2011)Soria AC, Villamiel M (2010) Effect of ultrasound on the technological properties and bioactivity of food: a review. Trends Food Sci Technol 21:323–331Starmans DAJ, Nijhuis HH (1996) Extraction of secondary metabolites from plant material: a review. Trends Food Sci Technol 7:191–197Sivakumar V, Lakshmi Anna J, Vijayeeswarri J, Swaminathan G (2009) Ultrasound assisted enhancement in natural dye extraction from beetroot for industrial applications and natural dyeing of leather. Ultrason Sonochem 16:782–789Stanisavljevic IT, Lazic ML, Veljkovic VB (2007) Ultrasonic extraction of oil from tobacco (Nicotiana tabacum L.) seeds. Ultrason Sonochem 14:646–652Sun Y, Liu D, Chen J, Ye X, Yu D (2011) Effects of different factors of ultrasound treatment on the extraction yield of the all-trans-b-carotene from citrus peels. Ultrason Sonochem 18:243–249Suslick KS (2001) Sonoluminescence and sonochemistry. In: Meyers RA (ed) Encyclopedia of physical science and technology, vol 17, 3rd edn. Academic Press, San Diego, pp 363–376Trabelsi F, Ait-Iyazidi H, Berlan J, Fabre PL, Delmas H, Wilhelm AM (1996) Electrochemical determination of the active zones in a high-frequency ultrasonic reactor. Ultrason Sonochem 3:125–130Veillet S, Tomao V, Chemat F (2010) Ultrasound assisted maceration: an original procedure for direct aromatisation of olive oil with basil. Food Chem 123:905–911Velickovic DT, Milenovic DM, Ristic MS, Veljkovic VB (2008) Ultrasonic extraction of waste solid residues from the Salvia sp. Essential oil hydrodistillation. Biochem Eng J 42:97–104Vercet A, Burgos J, Crelier S, Lopez-Buesa P (2001) Inactivation of proteases and lipases by ultrasound. Innovative Food Sci Emerg Technol 2:139–150Vilkhu K, Mawson R, Simons L, Bates D (2008) Applications and opportunities for ultrasound assisted extraction in the food industry—A review. Innovative Food Sci Emerg Technol 9:161–169Vinatoru M (2001) An overview of the ultrasonically assisted extraction of bioactive principles from herbs. Ultrason Sonochem 8:303–313Virot M, Tomao V, Le Bourvellec C, Renard CMCG, Chemat F (2010) Towards the industrial production of antioxidants from food processing by-products with ultrasound-assisted extraction. Ultrason Sonochem 17:1066–1074Wang J, Sun B, Cao Y, Tian Y, Li X (2008) Optimisation of ultrasound-assisted extraction of phenolic compounds from wheat bran. Food Chem 106:804–810Wang L, Weller CL (2006) Recent advances in extraction of nutraceuticals from plants. Trends Food Sci Technol 17:300–312Wei X, Chen M, Xiao Ja, Liu Y, Yu L, Zhang H, Wang Y (2010) Composition and bioactivity of tea flower polysaccharides obtained by different methods. Carbohydr Polym 79:418–422Weissler A, Cooper HW, Snyder S (1950) Chemical effects of ultrasonic waves: oxidation of potassium iodide solution by carbon tetrachloride. J Am Chem Soc 72:1769–1775Wulff-Pérez M, Torcello-Gómez A, Gálvez-Ruíz MJ, Martín-Rodríguez A (2009) Stability of emulsions for parenteral feeding: preparation and characterization of o/w nanoemulsions with natural oils and Pluronic f68 as surfactant. Food Hydrocolloids 23:1096–1102Yang B, Yang H, Li J, Li Z, Jiang Y (2011) Amino acid composition, molecular weight distribution and antioxidant activity of protein hydrolysates of soy sauce lees. Food Chem 124:551–555Yang Y, Zhang F (2008) Ultrasound-assisted extraction of rutin and quercetin from Euonymus alatus (Thunb.) Sieb. Ultrason Sonochem 15:308–313Zhang Z-S, Wang L-J, Li D, Jiao S-S, Chena XD, Maoa Z-H (2008) Ultrasound-assisted extraction of oil from flaxseed. Sep Purif Technol 62:192–198Zhang H-F, Yang X-H, Zhao L-D, Wang Y (2009) Ultrasonic-assisted extraction of epimedin C from fresh leaves of Epimedium and extraction mechanism. 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    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

    Localization and broadband follow-up of the gravitational-wave transient GW150914

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    A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the GW data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network circulars, giving an overview of the participating facilities, the GW sky localization coverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-up campaign are being disseminated in papers by the individual teams

    Mapping geographical inequalities in oral rehydration therapy coverage in low-income and middle-income countries, 2000-17

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    Background Oral rehydration solution (ORS) is a form of oral rehydration therapy (ORT) for diarrhoea that has the potential to drastically reduce child mortality; yet, according to UNICEF estimates, less than half of children younger than 5 years with diarrhoea in low-income and middle-income countries (LMICs) received ORS in 2016. A variety of recommended home fluids (RHF) exist as alternative forms of ORT; however, it is unclear whether RHF prevent child mortality. Previous studies have shown considerable variation between countries in ORS and RHF use, but subnational variation is unknown. This study aims to produce high-resolution geospatial estimates of relative and absolute coverage of ORS, RHF, and ORT (use of either ORS or RHF) in LMICs. Methods We used a Bayesian geostatistical model including 15 spatial covariates and data from 385 household surveys across 94 LMICs to estimate annual proportions of children younger than 5 years of age with diarrhoea who received ORS or RHF (or both) on continuous continent-wide surfaces in 2000-17, and aggregated results to policy-relevant administrative units. Additionally, we analysed geographical inequality in coverage across administrative units and estimated the number of diarrhoeal deaths averted by increased coverage over the study period. Uncertainty in the mean coverage estimates was calculated by taking 250 draws from the posterior joint distribution of the model and creating uncertainty intervals (UIs) with the 2 center dot 5th and 97 center dot 5th percentiles of those 250 draws. Findings While ORS use among children with diarrhoea increased in some countries from 2000 to 2017, coverage remained below 50% in the majority (62 center dot 6%; 12 417 of 19 823) of second administrative-level units and an estimated 6 519 000 children (95% UI 5 254 000-7 733 000) with diarrhoea were not treated with any form of ORT in 2017. Increases in ORS use corresponded with declines in RHF in many locations, resulting in relatively constant overall ORT coverage from 2000 to 2017. Although ORS was uniformly distributed subnationally in some countries, within-country geographical inequalities persisted in others; 11 countries had at least a 50% difference in one of their units compared with the country mean. Increases in ORS use over time were correlated with declines in RHF use and in diarrhoeal mortality in many locations, and an estimated 52 230 diarrhoeal deaths (36 910-68 860) were averted by scaling up of ORS coverage between 2000 and 2017. Finally, we identified key subnational areas in Colombia, Nigeria, and Sudan as examples of where diarrhoeal mortality remains higher than average, while ORS coverage remains lower than average. Interpretation To our knowledge, this study is the first to produce and map subnational estimates of ORS, RHF, and ORT coverage and attributable child diarrhoeal deaths across LMICs from 2000 to 2017, allowing for tracking progress over time. Our novel results, combined with detailed subnational estimates of diarrhoeal morbidity and mortality, can support subnational needs assessments aimed at furthering policy makers' understanding of within-country disparities. Over 50 years after the discovery that led to this simple, cheap, and life-saving therapy, large gains in reducing mortality could still be made by reducing geographical inequalities in ORS coverage. Copyright (c) 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

    Gravitational Waves and Gamma-Rays from a Binary Neutron Star Merger: GW170817 and GRB 170817A

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    On 2017 August 17, the gravitational-wave event GW170817 was observed by the Advanced LIGO and Virgo detectors, and the gamma-ray burst (GRB) GRB 170817A was observed independently by the Fermi Gamma-ray Burst Monitor, and the Anti-Coincidence Shield for the Spectrometer for the International Gamma-Ray Astrophysics Laboratory. The probability of the near-simultaneous temporal and spatial observation of GRB 170817A and GW170817 occurring by chance is 5.0×1085.0\times {10}^{-8}. We therefore confirm binary neutron star mergers as a progenitor of short GRBs. The association of GW170817 and GRB 170817A provides new insight into fundamental physics and the origin of short GRBs. We use the observed time delay of (+1.74±0.05)s(+1.74\pm 0.05)\,{\rm{s}} between GRB 170817A and GW170817 to: (i) constrain the difference between the speed of gravity and the speed of light to be between 3×1015-3\times {10}^{-15} and +7×1016+7\times {10}^{-16} times the speed of light, (ii) place new bounds on the violation of Lorentz invariance, (iii) present a new test of the equivalence principle by constraining the Shapiro delay between gravitational and electromagnetic radiation. We also use the time delay to constrain the size and bulk Lorentz factor of the region emitting the gamma-rays. GRB 170817A is the closest short GRB with a known distance, but is between 2 and 6 orders of magnitude less energetic than other bursts with measured redshift. A new generation of gamma-ray detectors, and subthreshold searches in existing detectors, will be essential to detect similar short bursts at greater distances. Finally, we predict a joint detection rate for the Fermi Gamma-ray Burst Monitor and the Advanced LIGO and Virgo detectors of 0.1-1.4 per year during the 2018-2019 observing run and 0.3-1.7 per year at design sensitivity

    Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model

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    We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO's second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h095%=3.47×10-25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering. © 2019 American Physical Society

    Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model

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    We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO’s second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h95%0=3.47×10−25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering

    First Measurement of the Hubble Constant from a Dark Standard Siren using the Dark Energy Survey Galaxies and the LIGO/Virgo Binary-Black-hole Merger GW170814

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    We present a multi-messenger measurement of the Hubble constant H 0 using the binary–black-hole merger GW170814 as a standard siren, combined with a photometric redshift catalog from the Dark Energy Survey (DES). The luminosity distance is obtained from the gravitational wave signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO)/Virgo Collaboration (LVC) on 2017 August 14, and the redshift information is provided by the DES Year 3 data. Black hole mergers such as GW170814 are expected to lack bright electromagnetic emission to uniquely identify their host galaxies and build an object-by-object Hubble diagram. However, they are suitable for a statistical measurement, provided that a galaxy catalog of adequate depth and redshift completion is available. Here we present the first Hubble parameter measurement using a black hole merger. Our analysis results in H0=7532+40kms1Mpc1{H}_{0}={75}_{-32}^{+40}\,\mathrm{km}\,{{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1}, which is consistent with both SN Ia and cosmic microwave background measurements of the Hubble constant. The quoted 68% credible region comprises 60% of the uniform prior range [20, 140] km s−1 Mpc−1, and it depends on the assumed prior range. If we take a broader prior of [10, 220] km s−1 Mpc−1, we find {H}_{0 {78}_{-24}^{+96}\,\mathrm{km}\,{{\rm{s}}}^{-1}\,{\mathrm{Mpc}}^{-1} (57% of the prior range). Although a weak constraint on the Hubble constant from a single event is expected using the dark siren method, a multifold increase in the LVC event rate is anticipated in the coming years and combinations of many sirens will lead to improved constraints on H 0
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