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Chapter 10 - Capacitation and Acrosome Reaction: Histochemical Techniques to Determine Acrosome Reaction
- Edited by Ashok Agarwal, Ralf Henkel, University of the Western Cape, South Africa, Ahmad Majzoub
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- Book:
- Manual of Sperm Function Testing in Human Assisted Reproduction
- Published online:
- 05 April 2021
- Print publication:
- 15 April 2021, pp 81-92
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Summary
Fertilization is an exceptionally specific cell recognition event that represents the culmination of a complex sequence of morphological and functional maturational events. In the case of the male gamete, this process is initiated by the commitment of spermatogonial stem cells to differentiate, sequentially forming spermatogonia, spermatocytes and eventually spermatozoa that are released into the lumen of the seminiferous tubules [1]. In addition to meiotic divisions, this process encompasses extensive cytoplasmic, organelle and nuclear remodeling events, thus establishing the unique and highly polarized architecture of the mature spermatozoon. A key aspect of this phase of development is the modification and repositioning of the Golgi apparatus to form a highly specialized secretory organelle, known as the acrosome, overlying the anterior aspect of the sperm head. Upon release from the testes the functionally immature spermatozoa enter the epididymis where they are progressively remodeled and acquire both motility and the potential to fertilize an oocyte [2]. This potential is eventually realized after passage through the female reproductive tract whereupon the ejaculated cells complete a suite of biochemical and biophysical changes known as capacitation [3]. These successive phases of functional maturation culminate in the acquired ability to release the acrosomal contents, during an event known as the acrosome reaction. This unique exocytotic event facilitates sperm passage through the outer vestments of the oocyte and is essential for successful in vivo fertilization in all mammalian species, including the human [4]. Consequently, failure of acrosomal exocytosis represents a common etiology in defective spermatozoa of male infertility patients that have failed in vitro fertilization (IVF) in a clinical setting; accounting for as much as 29 percent of unexplained male infertility cases [5, 6]. Much of our current mechanistic understanding of the acrosome reaction is grounded in the ability to stimulate this process in vitro using simple chemically defined media and the application of pharmacological interventions, and/or transgenic mouse models. Here, we discuss the biological significance of the acrosome reaction and the application of histochemical techniques that have been developed to study the progression and completion of this critical physiological event.
An ultra-wide bandwidth (704 to 4 032 MHz) receiver for the Parkes radio telescope
- George Hobbs, Richard N. Manchester, Alex Dunning, Andrew Jameson, Paul Roberts, Daniel George, J. A. Green, John Tuthill, Lawrence Toomey, Jane F. Kaczmarek, Stacy Mader, Malte Marquarding, Azeem Ahmed, Shaun W. Amy, Matthew Bailes, Ron Beresford, N. D. R. Bhat, Douglas C.-J. Bock, Michael Bourne, Mark Bowen, Michael Brothers, Andrew D. Cameron, Ettore Carretti, Nick Carter, Santy Castillo, Raji Chekkala, Wan Cheng, Yoon Chung, Daniel A. Craig, Shi Dai, Joanne Dawson, James Dempsey, Paul Doherty, Bin Dong, Philip Edwards, Tuohutinuer Ergesh, Xuyang Gao, JinLin Han, Douglas Hayman, Balthasar Indermuehle, Kanapathippillai Jeganathan, Simon Johnston, Henry Kanoniuk, Michael Kesteven, Michael Kramer, Mark Leach, Vince Mcintyre, Vanessa Moss, Stefan Osłowski, Chris Phillips, Nathan Pope, Brett Preisig, Daniel Price, Ken Reeves, Les Reilly, John Reynolds, Tim Robishaw, Peter Roush, Tim Ruckley, Elaine Sadler, John Sarkissian, Sean Severs, Ryan Shannon, Ken Smart, Malcolm Smith, Stephanie Smith, Charlotte Sobey, Lister Staveley-Smith, Anastasios Tzioumis, Willem van Straten, Nina Wang, Linqing Wen, Matthew Whiting
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- Journal:
- Publications of the Astronomical Society of Australia / Volume 37 / 2020
- Published online by Cambridge University Press:
- 08 April 2020, e012
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- Article
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We describe an ultra-wide-bandwidth, low-frequency receiver recently installed on the Parkes radio telescope. The receiver system provides continuous frequency coverage from 704 to 4032 MHz. For much of the band ( ${\sim}60\%$ ), the system temperature is approximately 22 K and the receiver system remains in a linear regime even in the presence of strong mobile phone transmissions. We discuss the scientific and technical aspects of the new receiver, including its astronomical objectives, as well as the feed, receiver, digitiser, and signal processor design. We describe the pipeline routines that form the archive-ready data products and how those data files can be accessed from the archives. The system performance is quantified, including the system noise and linearity, beam shape, antenna efficiency, polarisation calibration, and timing stability.
Contributors
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- By Yasir Abu-Omar, Matthew E. Atkins, Joseph E. Arrowsmith, Alan Ashworth, Rubia Baldassarri, Craig R. Bailey, David J. Barron, Christiana C. Burt, David Cardone, Coralie Carle, Jose Coddens, Alan M. Cohen, Simon Colah, Sarah Conolly, David J. Daly, Helen M. Daly, Stefan G. De Hert, Ravi J. De Silva, Mark Dougherty, John J. Dunning, Maros Elsik, Betsy Evans, Florian Falter, Nigel Farnum, Jens Fassl, Juliet E. Foweraker, Simon P. Fynn, Andrew I. Gardner, Margaret I. Gillham, Martin J. Goddard, Maximilien J. Gourdin, Jon Graham, Stephen J. Gray, Cameron Graydon, Fabio Guarracino, Roger M. O. Hall, Michael Haney, Charles W. Hogue, Ben W. Howes, Bevan Hughes, Siân I. Jaggar, David P. Jenkins, Jörn Karhausen, Todd Kiefer, Khalid Khan, Andrew A. Klein, John D. Kneeshaw, Andrew C. Knowles, Catherine V. Koffel, R. Clive Landis, Trevor W. R. Lee, Clive J. Lewis, Jonathan H. Mackay, Amod Manocha, Jonathan B. Mark, Sarah Marstin, William T. McBride, Kenneth H. McKinlay, Alan F. Merry, Berend Mets, Britta Millhoff, Kevin P. Morris, Samer A. M. Nashef, Andrew Neitzel, Stephane Noble, Rabi Panigrahi, Barbora Parizkova, J. M. Tom Pierce, Mihai V. Podgoreanu, Hans-Joachim Priebe, Paul Quinton, C. Ramaswamy Rajamohan, Doris M. Rassl, Tom Rawlings, Fiona E. Reynolds, Andrew J. Richardson, David Riddington, Andrew Roscoe, Paul H. M. Sadleir, Ving Yuen See Tho, Herve Schlotterbeck, Maura Screaton, Shitalkumar Shah, Harjot Singh, Jon H. Smith, M. L. Srikanth, Yeewei W. Teo, Kamen P. Valchanov, Jean-Pierre van Besouw, Isabeau A. Walker, Stephen T. Webb, Francis C. Wells, John Whitbread, Charles Willmott, Patrick Wouters
- Edited by Jonathan H. Mackay, Joseph E. Arrowsmith
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- Book:
- Core Topics in Cardiac Anesthesia
- Published online:
- 05 April 2012
- Print publication:
- 15 March 2012, pp x-xiii
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