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The mediating role of health behaviors in the association between depression, anxiety and cancer incidence: an individual participant data meta-analysis
- Kuan-Yu Pan, Lonneke van Tuijl, Maartje Basten, Judith J. M. Rijnhart, Alexander de Graeff, Joost Dekker, Mirjam I. Geerlings, Adriaan Hoogendoorn, Adelita V. Ranchor, Roel Vermeulen, Lützen Portengen, Adri C. Voogd, Jessica Abell, Philip Awadalla, Aartjan T. F. Beekman, Ottar Bjerkeset, Andy Boyd, Yunsong Cui, Philipp Frank, Henrike Galenkamp, Bert Garssen, Sean Hellingman, Monika Hollander, Martijn Huisman, Anke Huss, Melanie R. Keats, Almar A. L. Kok, Steinar Krokstad, Flora E. van Leeuwen, Annemarie I. Luik, Nolwenn Noisel, Yves Payette, Brenda W. J. H. Penninx, Susan Picavet, Ina Rissanen, Annelieke M. Roest, Judith G. M. Rosmalen, Rikje Ruiter, Robert A. Schoevers, David Soave, Mandy Spaan, Andrew Steptoe, Karien Stronks, Erik R. Sund, Ellen Sweeney, Alison Teyhan, Emma L. Twait, Kimberly D. van der Willik, Femke Lamers
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- Journal:
- Psychological Medicine , First View
- Published online by Cambridge University Press:
- 29 April 2024, pp. 1-14
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Background
Although behavioral mechanisms in the association among depression, anxiety, and cancer are plausible, few studies have empirically studied mediation by health behaviors. We aimed to examine the mediating role of several health behaviors in the associations among depression, anxiety, and the incidence of various cancer types (overall, breast, prostate, lung, colorectal, smoking-related, and alcohol-related cancers).
MethodsTwo-stage individual participant data meta-analyses were performed based on 18 cohorts within the Psychosocial Factors and Cancer Incidence consortium that had a measure of depression or anxiety (N = 319 613, cancer incidence = 25 803). Health behaviors included smoking, physical inactivity, alcohol use, body mass index (BMI), sedentary behavior, and sleep duration and quality. In stage one, path-specific regression estimates were obtained in each cohort. In stage two, cohort-specific estimates were pooled using random-effects multivariate meta-analysis, and natural indirect effects (i.e. mediating effects) were calculated as hazard ratios (HRs).
ResultsSmoking (HRs range 1.04–1.10) and physical inactivity (HRs range 1.01–1.02) significantly mediated the associations among depression, anxiety, and lung cancer. Smoking was also a mediator for smoking-related cancers (HRs range 1.03–1.06). There was mediation by health behaviors, especially smoking, physical inactivity, alcohol use, and a higher BMI, in the associations among depression, anxiety, and overall cancer or other types of cancer, but effects were small (HRs generally below 1.01).
ConclusionsSmoking constitutes a mediating pathway linking depression and anxiety to lung cancer and smoking-related cancers. Our findings underline the importance of smoking cessation interventions for persons with depression or anxiety.
Agricultural Research Service Weed Science Research: Past, Present, and Future
- Stephen L. Young, James V. Anderson, Scott R. Baerson, Joanna Bajsa-Hirschel, Dana M. Blumenthal, Chad S. Boyd, Clyde D. Boyette, Eric B. Brennan, Charles L. Cantrell, Wun S. Chao, Joanne C. Chee-Sanford, Charlie D. Clements, F. Allen Dray, Stephen O. Duke, Kayla M. Eason, Reginald S. Fletcher, Michael R. Fulcher, John F. Gaskin, Brenda J. Grewell, Erik P. Hamerlynck, Robert E. Hoagland, David P. Horvath, Eugene P. Law, John D. Madsen, Daniel E. Martin, Clint Mattox, Steven B. Mirsky, William T. Molin, Patrick J. Moran, Rebecca C. Mueller, Vijay K. Nandula, Beth A. Newingham, Zhiqiang Pan, Lauren M. Porensky, Paul D. Pratt, Andrew J. Price, Brian G. Rector, Krishna N. Reddy, Roger L. Sheley, Lincoln Smith, Melissa C. Smith, Keirith A. Snyder, Matthew A. Tancos, Natalie M. West, Gregory S. Wheeler, Martin M. Williams, Julie Wolf, Carissa L. Wonkka, Alice A. Wright, Jing Xi, Lew H. Ziska
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- Journal:
- Weed Science / Volume 71 / Issue 4 / July 2023
- Published online by Cambridge University Press:
- 16 August 2023, pp. 312-327
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The U.S. Department of Agriculture–Agricultural Research Service (USDA-ARS) has been a leader in weed science research covering topics ranging from the development and use of integrated weed management (IWM) tactics to basic mechanistic studies, including biotic resistance of desirable plant communities and herbicide resistance. ARS weed scientists have worked in agricultural and natural ecosystems, including agronomic and horticultural crops, pastures, forests, wild lands, aquatic habitats, wetlands, and riparian areas. Through strong partnerships with academia, state agencies, private industry, and numerous federal programs, ARS weed scientists have made contributions to discoveries in the newest fields of robotics and genetics, as well as the traditional and fundamental subjects of weed–crop competition and physiology and integration of weed control tactics and practices. Weed science at ARS is often overshadowed by other research topics; thus, few are aware of the long history of ARS weed science and its important contributions. This review is the result of a symposium held at the Weed Science Society of America’s 62nd Annual Meeting in 2022 that included 10 separate presentations in a virtual Weed Science Webinar Series. The overarching themes of management tactics (IWM, biological control, and automation), basic mechanisms (competition, invasive plant genetics, and herbicide resistance), and ecosystem impacts (invasive plant spread, climate change, conservation, and restoration) represent core ARS weed science research that is dynamic and efficacious and has been a significant component of the agency’s national and international efforts. This review highlights current studies and future directions that exemplify the science and collaborative relationships both within and outside ARS. Given the constraints of weeds and invasive plants on all aspects of food, feed, and fiber systems, there is an acknowledged need to face new challenges, including agriculture and natural resources sustainability, economic resilience and reliability, and societal health and well-being.
Ten new insights in climate science 2022
- Maria A. Martin, Emmanuel A. Boakye, Emily Boyd, Wendy Broadgate, Mercedes Bustamante, Josep G. Canadell, Edward R. Carr, Eric K. Chu, Helen Cleugh, Szilvia Csevár, Marwa Daoudy, Ariane de Bremond, Meghnath Dhimal, Kristie L. Ebi, Clea Edwards, Sabine Fuss, Martin P. Girardin, Bruce Glavovic, Sophie Hebden, Marina Hirota, Huang-Hsiung Hsu, Saleemul Huq, Karin Ingold, Ola M. Johannessen, Yasuko Kameyama, Nilushi Kumarasinghe, Gaby S. Langendijk, Tabea Lissner, Shuaib Lwasa, Catherine Machalaba, Aaron Maltais, Manu V. Mathai, Cheikh Mbow, Karen E. McNamara, Aditi Mukherji, Virginia Murray, Jaroslav Mysiak, Chukwumerije Okereke, Daniel Ospina, Friederike Otto, Anjal Prakash, Juan M. Pulhin, Emmanuel Raju, Aaron Redman, Kanta K. Rigaud, Johan Rockström, Joyashree Roy, E. Lisa F. Schipper, Peter Schlosser, Karsten A. Schulz, Kim Schumacher, Luana Schwarz, Murray Scown, Barbora Šedová, Tasneem A. Siddiqui, Chandni Singh, Giles B. Sioen, Detlef Stammer, Norman J. Steinert, Sunhee Suk, Rowan Sutton, Lisa Thalheimer, Maarten van Aalst, Kees van der Geest, Zhirong Jerry Zhao
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- Journal:
- Global Sustainability / Volume 5 / 2022
- Published online by Cambridge University Press:
- 10 November 2022, e20
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Non-technical summary
We summarize what we assess as the past year's most important findings within climate change research: limits to adaptation, vulnerability hotspots, new threats coming from the climate–health nexus, climate (im)mobility and security, sustainable practices for land use and finance, losses and damages, inclusive societal climate decisions and ways to overcome structural barriers to accelerate mitigation and limit global warming to below 2°C.
Technical summaryWe synthesize 10 topics within climate research where there have been significant advances or emerging scientific consensus since January 2021. The selection of these insights was based on input from an international open call with broad disciplinary scope. Findings concern: (1) new aspects of soft and hard limits to adaptation; (2) the emergence of regional vulnerability hotspots from climate impacts and human vulnerability; (3) new threats on the climate–health horizon – some involving plants and animals; (4) climate (im)mobility and the need for anticipatory action; (5) security and climate; (6) sustainable land management as a prerequisite to land-based solutions; (7) sustainable finance practices in the private sector and the need for political guidance; (8) the urgent planetary imperative for addressing losses and damages; (9) inclusive societal choices for climate-resilient development and (10) how to overcome barriers to accelerate mitigation and limit global warming to below 2°C.
Social media summaryScience has evidence on barriers to mitigation and how to overcome them to avoid limits to adaptation across multiple fields.
The Scientific Programme of Skylark to Mid-1960
- R. L. F. Boyd
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- The Aeronautical Journal / Volume 65 / Issue 608 / August 1961
- Published online by Cambridge University Press:
- 04 July 2016, pp. 531-532
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Today we are Interested in the scope of the research programme rather than the actual details of the physics. Further I shall discuss space research rather than just upper atmosphere research, because we include astronomy and this will be discussed by others as well.
Now I have, in fact, a formidable task, because I find I have something like twenty-three experiments to deal with in twenty minutes. What I am going to do therefore is to list the experiments that are going on, to tell you whether they have been carried out successfully, or are awaiting completion, and thus to try to give you some idea of the scope of the work which has been undertaken.
Contributors
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- By Julie M. Allen, Marina S. Ascunce, Ahidjo Ayouba, David Bass, Frida Ben-Ami, Frédéric Bordes, Bret M. Boyd, Rodney A. Bray, Aurélie Chambouvet, Philippe Christe, Julien Claude, Yves Desdevises, Carl W. Dick, Katharina Dittmar, Ashley Dowling, Bryan G. Falk, Martín García-Varela, Rebecca Rose Gray, Michael W. Hastriter, Hadas Hawlena, Tine Huyse, James C. Iles, Tania Jenkins, Boris R. Krasnov, Armand M. Kuris, Tommy L. F. Leung, D. Timothy J. Littlewood, Peter V. Markov, Camilo Mora, Serge Morand, Solon F. Morse, Steve Nadler, Sigrid Neuhauser, Roderic Page, Bruce D. Patterson, Martine Peeters, Gerardo Pérez-Ponce de León, Susan L. Perkins, Timothée Poisot, Robert Poulin, Oliver G. Pybus, David L. Reed, Thomas A. Richards, Klaus Rohde, Lajos Rózsa, Andrea Šimková, Arne Skorping, Melissa A. Toups, Piotr Tryjanowski, Maarten P. M. Vanhove, Zoltán Vas, Andrea Waeschenbach, Lucy A. Weinert, Michael F. Whiting, Quin Zhu
- Edited by Serge Morand, Université de Montpellier II, Boris R. Krasnov, Ben-Gurion University of the Negev, Israel, D. Timothy J. Littlewood, Natural History Museum, London
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- Book:
- Parasite Diversity and Diversification
- Published online:
- 05 March 2015
- Print publication:
- 26 February 2015, pp viii-xii
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- By George Aiken, Andy Baker, Thomas J. Boyd, Rasmus Bro, Robert F. Chen, Paula G. Coble, Robyn N. Conmy, Rose M. Cory, Carlos E. Del Castillo, Rossana Del Vecchio, Bryan D. Downing, Rachel S. Gabor, John R. Gilchrist, Diane M. McKnight, Matthew P. Miller, Kathleen R. Murphy, Christopher L. Osburn, Darren M. Reynolds, Robert G. M. Spencer, Colin A. Stedmon
- Edited by Paula G. Coble, University of South Florida, Jamie Lead, University of South Carolina, Andy Baker, Darren M. Reynolds, University of the West of England, Bristol, Robert G. M. Spencer, Florida State University
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- Book:
- Aquatic Organic Matter Fluorescence
- Published online:
- 05 June 2014
- Print publication:
- 14 July 2014, pp ix-x
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- By H. Elliott Albers, Reut Avinun, Karen L. Bales, Jorge A. Barraza, Michael T. Bowen, Sunny K. Boyd, Heather K. Caldwell, Elena Choleris, Amy E. Clipperton-Allen, Bruce S. Cushing, Monica B. Dhakar, Riccardo Dore, Richard P. Ebstein, Craig F. Ferris, Sara M. Freeman, James L. Goodson, Joshua J. Green, Haruhiro Higashida, Eric Hollander, Salomon Israel, Martin Kavaliers, Keith M. Kendrick, Ariel Knafo, Yoav Litvin, Olga Lopatina, David Mankuta, Iain S. McGregor, Richard H. Melloni, Inga D. Neumann, Jerome H. Pagani, Cort A. Pedersen, Donald W. Pfaff, Anna Phan, Benjamin J. Ragen, Amina Sarwat, Idan Shalev, Erica L. Stevenson, Bonnie Taylor, Richmond R. Thompson, Florina Uzefovsky, Erwin H. van den Burg, James C. Walton, Scott R. Wersinger, Nurit Yirmiya, Larry J. Young, W. Scott Young, Paul J. Zak
- Edited by Elena Choleris, University of Guelph, Ontario, Donald W. Pfaff, Rockefeller University, New York, Martin Kavaliers, University of Western Ontario
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- Book:
- Oxytocin, Vasopressin and Related Peptides in the Regulation of Behavior
- Published online:
- 05 April 2013
- Print publication:
- 11 April 2013, pp xi-xiv
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- By Luis G. Acevedo, Schahram Akbarian, Ioanna Andreou, Krishnarao Appasani, Raghu K. Appasani, Julia Arand, David M. Ashley, Alexander R. Ball, Yehudit Bergman, Marina Bibikova, Angela Bithell, Francesca Bonafè, Eric E. Bouhassira, Victoria L. Boyd, Noel J. Buckley, Lars Olov Bygren, Claudio M. Caldarera, Gemma Carvill, James W. F. Catto, Sarah Derks, Ewa Dudziec, Jeffrey D. Falk, Jian-Bing Fan, Joseph M. Fernandez, David E. Fisher, Emanuela Fiumana, Tamara B. Franklin, Fei Gao, Arkadiusz Gertych, Emanuele Giordano, David Goldman, Markus Grammel, Carlo Guarnieri, Kevin L. Gunderson, Victoria (Fatemeh) G. Haghighi, Xu Han, Yong-Mahn Han, Howard C. Hang, Aditi Hazra, Laura B.K. Herzing, Norbert Hochstein, Robin Holliday, Dorothee Honsel, Mary A. Jelinek, Guanyu Ji, Yan Jiang, Atsushi Kaneda, Richard A. Katz, Hyemin Kim, Richard Kroon, Tapas K. Kundu, Benoit Labonté, Daeyoup Lee, Konstantin Lepikhov, Andrea Linnemann-Florl, Dirk Loeffert, Dylan Maixner, Isabelle M. Mansuy, Andreas Missel, D. V. Mohankrishna, Joana Carvalho Moreira de Mello, Paolo G. Morselli, Rituparna Mukhopadhyay, Claudio Muscari, Takashi Nagano, Frank Narz, Shuji Ogino, Carlo M. Oranges, Shari Orlanski, Alice Pasini, Ralf Peist, Lygia V. Pereira, Andrey Poleshko, Claire Rougeulle, Thea Rütjes, Ana Sanz, Benjamin G. Schroeder, Gerald Schock, Kornel Schuebel, B. Ruthrotha Selvi, Hogyu Seo, Natalia Shalginskikh, Andrew Sharp, Jun S. Song, Lennart Suckau, Azim Surani, Jian Tajbakhsh, Gustavo Turecki, Céline Vallot, Manon van Engeland, Jörn Walter, Nicholas C. Wong, Mark Wossidlo, Honglong Wu, Yurong Xin, Zhixiang Yan, Yu-Ying Yang, Mingzhi Ye, Kyoko Yokomori, Sephorah Zaman, Weihua Zeng, Gerald Zon
- Edited by Krishnarao Appasani
- Foreword by Azim Surani, University of Cambridge
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- Book:
- Epigenomics
- Published online:
- 05 August 2012
- Print publication:
- 02 August 2012, pp x-xxiv
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- By Jane E. Adcock, Yahya Aghakhani, A. Anand, Eva Andermann, Frederick Andermann, Alexis Arzimanoglou, Sandrine Aubert, Nadia Bahi-Buisson, Carman Barba, Agatino Battaglia, Geneviève Bernard, Nadir E. Bharucha, Laurence A. Bindoff, William Bingaman, Francesca Bisulli, Thomas P. Bleck, Stewart G. Boyd, Andreas Brunklaus, Harry Bulstrode, Jorge G. Burneo, Laura Canafoglia, Laura Cantonetti, Roberto H. Caraballo, Fernando Cendes, Kevin E. Chapman, Patrick Chauvel, Richard F. M. Chin, H. T. Chong, Fahmida A. Chowdhury, Catherine J. Chu-Shore, Rolando Cimaz, Andrew J. Cole, Bernard Dan, Geoffrey Dean, Alessio De Ciantis, Fernando De Paolis, Rolando F. Del Maestro, Irissa M. Devine, Carlo Di Bonaventura, Concezio Di Rocco, Henry B. Dinsdale, Maria Alice Donati, François Dubeau, Michael Duchowny, Olivier Dulac, Monika Eisermann, Brent Elliott, Bernt A. Engelsen, Kevin Farrell, Natalio Fejerman, Rosalie E. Ferner, Silvana Franceschetti, Robert Friedlander, Antonio Gambardella, Hector H. Garcia, Serena Gasperini, Lorenzo Genitori, Gioia Gioi, Flavio Giordano, Leif Gjerstad, Daniel G. Glaze, Howard P. Goodkin, Sidney M. Gospe, Andrea Grassi, William P. Gray, Renzo Guerrini, Marie-Christine Guiot, William Harkness, Andrew G. Herzog, Linda Huh, Margaret J. Jackson, Thomas S. Jacques, Anna C. Jansen, Sigmund Jenssen, Michael R. Johnson, Dorothy Jones-Davis, Reetta Kälviäinen, Peter W. Kaplan, John F. Kerrigan, Autumn Marie Klein, Matthias Koepp, Edwin H. Kolodny, Kandan Kulandaivel, Ruben I. Kuzniecky, Ahmed Lary, Yolanda Lau, Anna-Elina Lehesjoki, Maria K. Lehtinen, Holger Lerche, Michael P. T. Lunn, Snezana Maljevic, Mark R. Manford, Carla Marini, Bindu Menon, Giulia Milioli, Eli M. Mizrahi, Manish Modi, Márcia Elisabete Morita, Manuel Murie-Fernandez, Vivek Nambiar, Lina Nashef, Vincent Navarro, Aidan Neligan, Ruth E. Nemire, Charles R. J. C. Newton, John O'Donavan, Hirokazu Oguni, Teiichi Onuma, Andre Palmini, Eleni Panagiotakaki, Pasquale Parisi, Elena Parrini, Liborio Parrino, Ignacio Pascual-Castroviejo, M. Scott Perry, Perrine Plouin, Charles E. Polkey, Suresh S. Pujar, Karthik Rajasekaran, R. Eugene Ramsey, Rahul Rathakrishnan, Roberta H. Raven, Guy M. Rémillard, David Rosenblatt, M. Elizabeth Ross, Abdulrahman Sabbagh, P. Satishchandra, Swati Sathe, Ingrid E. Scheffer, Philip A. Schwartzkroin, Rod C. Scott, Frédéric Sedel, Michelle J. Shapiro, Elliott H. Sherr, Michael Shevell, Simon D. Shorvon, Adrian M. Siegel, Gagandeep Singh, S. Sinha, Barbara Spacca, Waney Squier, Carl E. Stafstrom, Bernhard J. Steinhoff, Andrea Taddio, Gianpiero Tamburrini, C. T. Tan, Raymond Y. L. Tan, Erik Taubøll, Robert W. Teasell, Mario Giovanni Terzano, Federica Teutonico, Suzanne A. Tharin, Elizabeth A. Thiele, Pierre Thomas, Paolo Tinuper, Dorothée Kasteleijn-Nolst Trenité, Sumeet Vadera, Pierangelo Veggiotti, Jean-Pierre Vignal, J. M. Walshe, Elizabeth J. Waterhouse, David Watkins, Ruth E. Williams, Yue-Hua Zhang, Benjamin Zifkin, Sameer M. Zuberi
- Edited by Simon D. Shorvon, Frederick Andermann, Renzo Guerrini
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- Book:
- The Causes of Epilepsy
- Published online:
- 05 March 2012
- Print publication:
- 14 April 2011, pp ix-xvi
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- By Saleh H. Alwasel, Susan P. Bagby, David J. P Barker, Richard Boyd, Robert Boyd, Graham Burdge, Graham J Burton, Anthony M Carter, Irene Cetin, Zoe Cole, Cyrus Cooper, Hilary Critchley, Elaine Dennison, Susie Earl, Johan G Eriksson, Caroline H. D Fall, Anne C. Ferguson-Smith, Tom P. Fleming, Alison J. Forhead, Abigail L. Fowden, Dino Giussani, Laura Goodfellow, Nicholas Harvey, Christopher Holroyd, Joan Hunt, Alan A. Jackson, Thomas Jansson, Eric Jauniaux, Rosalind John, Eero Kajantie, Michelle Lampl, Karen Lillycrop, Charlie Loke, Samantha Louey, Per Magnus, Ashley Moffett, Lorna G. Moore, Terry Morgan, Clive Osmond, Perrie F. O'Tierney, Robert Pijnenborg, Lucilla Poston, Theresa L. Powell, Elizabeth J. Radford, Tessa J. Roseboom, Amanda Sferruzzi-Perri, Colin P. Sibley, Gordon C. S. Smith, Emanuela Taricco, Kent Thornburg, Benjamin Tycko, Owen R. Vaughan, Lisbeth Vercruysse
- Edited by Graham J. Burton, David J. P. Barker, Ashley Moffett, Kent Thornburg
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- Book:
- The Placenta and Human Developmental Programming
- Published online:
- 04 February 2011
- Print publication:
- 16 December 2010, pp vii-x
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Direct milk excretion of Campylobacter jejuni in a dairy cow causing cases of human enteritis
- K. E. Orr, N. F. Lightfoot, P. R. Sisson, B. A. Harkis, J. L. Tweddle, P. Boyd, A. Carroll, C. J. Jackson, D. R. A. Wareing, R. Freeman
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- Journal:
- Epidemiology & Infection / Volume 114 / Issue 1 / February 1995
- Published online by Cambridge University Press:
- 15 May 2009, pp. 15-24
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Consumption of milk contaminated with Campylobacter jejuni has been described as a cause of human enteritis. Although faecal contamination of milk with the organism has frequently been described, direct milk excretion of Campylobacter jejuni into milk has rarely been linked with cases of human infection. We describe the investigations undertaken following the isolation of Campylobacter jejuni from samples of unpasteurized milk prior to retail. Results of epidemiological investigations including typing of Campylobacter jejuni isolates using pyrolysis mass spectrometry, Penner and Lior serotyping, biotyping, phage typing and restriction fragment length polymorphism analysis provided convincing evidence implicating direct milk excretion of Campylobacter jejuni by one asymptomatic dairy cow as the source of the milk contamination and the cause of local cases of human enteritis.
Fertility of inseminations with two sperm concentrations in oestrus-synchronized cattle
- L. J. Boyd, G. F. Smith, P. D. P. Wood, J. Craven, D. R. Melrose, J. Williamson
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- Journal:
- Animal Production / Volume 17 / Issue 2 / October 1973
- Published online by Cambridge University Press:
- 02 September 2010, pp. 163-168
- Print publication:
- October 1973
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Two field trials were conducted to evaluate oestrus synchronization under farm conditions and to determine if increased sperm numbers per insemination would enhance fertility at the first synchronized oestrus. One hundred and seventy-seven previously unmated British Friesian females in 6 dairy herds and 236 suckler cows in 9 beef herds were used. Treated animals received 1·0 mg melengestrol acetate (MGA) daily for 14 days. Treated and control animals were inseminated with either 15 or 60 million sperm per first insemination.
Oestrus was synchronized in 94% of the treated dairy heifers and 66% of the treated suckler cows. Oestrus detection by herdsmen appeared to be much less precise in suckler herds than in the dairy herds.
First inseminations were given during a 21-day breeding period (commencing at withdrawal of MGA) to 97% of treated and 79% of control dairy heifers (P<0·01), and to 77% of the treated and 69% of the control suckler cows (P>0·05). On an average, first inseminations were given 10 days earlier to treated heifers and 7 days earlier to treated suckler cows than to their control counterparts. The 45-day non-return rate to first inseminations was 81% for control and 41% for treated dairy heifers (P< 0·001) and 69% for control and 46% for treated suckler cows (P>0·05).
Oestrus-synchronized animals required significantly more services than control animals during a 30-day breeding period. However, there was no difference between treated and control animals in the non-return rate to one or more services given during the prescribed 30-day breeding period.
Insemination with 15 or 60 million live sperm had no effect on the non-return rate of treated or control animals.