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Cosmology with Phase 1 of the Square Kilometre Array Red Book 2018: Technical specifications and performance forecasts
- Part of
- Square Kilometre Array Cosmology Science Working Group:, David J. Bacon, Richard A. Battye, Philip Bull, Stefano Camera, Pedro G. Ferreira, Ian Harrison, David Parkinson, Alkistis Pourtsidou, Mário G. Santos, Laura Wolz, Filipe Abdalla, Yashar Akrami, David Alonso, Sambatra Andrianomena, Mario Ballardini, José Luis Bernal, Daniele Bertacca, Carlos A. P. Bengaly, Anna Bonaldi, Camille Bonvin, Michael L. Brown, Emma Chapman, Song Chen, Xuelei Chen, Steven Cunnington, Tamara M. Davis, Clive Dickinson, José Fonseca, Keith Grainge, Stuart Harper, Matt J. Jarvis, Roy Maartens, Natasha Maddox, Hamsa Padmanabhan, Jonathan R. Pritchard, Alvise Raccanelli, Marzia Rivi, Sambit Roychowdhury, Martin Sahlén, Dominik J. Schwarz, Thilo M. Siewert, Matteo Viel, Francisco Villaescusa-Navarro, Yidong Xu, Daisuke Yamauchi, Joe Zuntz
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 37 / 2020
- Published online by Cambridge University Press:
- 06 March 2020, e007
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- Article
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We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 of the Square Kilometre Array (SKA1) and the science that they will enable. We highlight three main surveys: a medium-deep continuum weak lensing and low-redshift spectroscopic HI galaxy survey over 5 000 deg2; a wide and deep continuum galaxy and HI intensity mapping (IM) survey over 20 000 deg2 from $z = 0.35$ to 3; and a deep, high-redshift HI IM survey over 100 deg2 from $z = 3$ to 6. Taken together, these surveys will achieve an array of important scientific goals: measuring the equation of state of dark energy out to $z \sim 3$ with percent-level precision measurements of the cosmic expansion rate; constraining possible deviations from General Relativity on cosmological scales by measuring the growth rate of structure through multiple independent methods; mapping the structure of the Universe on the largest accessible scales, thus constraining fundamental properties such as isotropy, homogeneity, and non-Gaussianity; and measuring the HI density and bias out to $z = 6$ . These surveys will also provide highly complementary clustering and weak lensing measurements that have independent systematic uncertainties to those of optical and near-infrared (NIR) surveys like Euclid, LSST, and WFIRST leading to a multitude of synergies that can improve constraints significantly beyond what optical or radio surveys can achieve on their own. This document, the 2018 Red Book, provides reference technical specifications, cosmological parameter forecasts, and an overview of relevant systematic effects for the three key surveys and will be regularly updated by the Cosmology Science Working Group in the run up to start of operations and the Key Science Programme of SKA1.
22 - Inguinal and umbilical hernias
- from Part IV - Abdomen
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- By Emma J. Parkinson, Department of Paediatric Surgery, Institute of Child Health, London, UK, Agostino Pierro, Department of Paediatric Surgery, Institute of Child Health, London, UK
- Edited by Mark D. Stringer, Keith T. Oldham, Pierre D. E. Mouriquand
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- Book:
- Pediatric Surgery and Urology
- Published online:
- 08 January 2010
- Print publication:
- 09 November 2006, pp 286-295
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Summary
Inguinal hernia
The patent processus vaginalis is the common element in the pathogenesis of both congenital indirect inguinal hernia and congenital hydrocele. A wide patent processus creates a hernia by permitting the passage of intra-abdominal organs into the hernia sac, a hydrocele has a narrower processus permitting the passage of intraperitoneal fluid only. An inguinal hernia commonly presents as a reducible groin mass emerging from the external inguinal ring, lateral to the pubic tubercle, and may extend into the scrotum.
Congenital indirect inguinal hernias are one of the most common surgical conditions in infancy with a peak incidence in the first three months of life, occurring in approximately 3.5 to 5% of full-term neonates. In premature infants the incidence increases further, up to approximately 30%.
Boys have an increased incidence (male to female ratio between 8:1 and 12:1). In both sexes the incidence of right-sided inguinal hernia is higher than left (right 64%, left 29%, bilateral 7%). Consequently, patients presenting initially with a left-sided hernia have a higher probability of developing a metachronous hernia.
Specific abnormalities predispose to the development of inguinal hernia early in life. Prematurity is the most important risk factor (Table 22.1). These conditions represent part of a whole spectrum of incomplete obliteration of the processus vaginalis which leads to the potential development of both hydroceles and inguinal hernias.
Historical aspects
There is evidence from 1552 BC that the Egyptians described inguinal hernias controlled by external pressure.