Exposure to agricultural pesticide impairs visual lateralization in a larval coral reef fish

Lateralization, i.e. the preferential use of one side of the body, may convey fitness benefits for organisms within rapidly-changing environments, by optimizing separate and parallel processing of different information between the two brain hemispheres. In coral reef-fishes, the movement of larvae from planktonic to reef environments (recruitment) represents a major life-history transition. This transition requires larvae to rapidly identify and respond to sensory cues to select a suitable habitat that facilitates survival and growth. This \u27recruitment\u27 is critical for population persistence and resilience. In aquarium experiments, larval Acanthurus triostegus preferentially used their right-eye to investigate a variety of visual stimuli. Despite this, when held in in situ cages with predators, those larvae that previously favored their left-eye exhibited higher survival. These results support the "brain\u27s right-hemisphere" theory, which predicts that the right-eye (i.e. left-hemisphere) is used to categorize stimuli while the left-eye (i.e. right-hemisphere) is used to inspect novel items and initiate rapid behavioral-responses. While these experiments confirm that being highly lateralized is ecologically advantageous, exposure to chlorpyrifos, a pesticide often inadvertently added to coral-reef waters, impaired visual-lateralization. This suggests that chemical pollutants could impair the brain function of larval fishes during a critical life-history transition, potentially impacting recruitment success

Boat noise prevents soundscape-based habitat selection by coral planulae

Understanding the relationship between coral reef condition and recruitment potential is vital for the development of effective management strategies that maintain coral cover and biodiversity. Coral larvae (planulae) have been shown to use certain sensory cues to orient towards settlement habitats (e.g. the odour of live crustose coralline algae - CCA). However, the influence of auditory cues on coral recruitment, and any effect of anthropogenic noise on this process, remain largely unknown. Here, we determined the effect of protected reef (MPA), exploited reef (non-MPA) soundscapes, and a source of anthropogenic noise (boat) on the habitat preference for live CCA over dead CCA in the planula of two common Indo-Pacific coral species (Pocillopora damicornis and Acropora cytherea). Soundscapes from protected reefs significantly increased the phonotaxis of planulae of both species towards live CCA, especially when compared to boat noise. Boat noise playback prevented this preferential selection of live CCA as a settlement substrate. These results suggest that sources of anthropogenic noise such as motor boat can disrupt the settlement behaviours of coral planulae. Acoustic cues should be accounted for when developing management strategies aimed at maximizing larval recruitment to coral reefs

Consistency in the supply of larval fishes among coral reefs in French Polynesia

For marine fishes with a bipartite life cycle, pelagic larval dispersal can shape the distribution, connectivity, composition and resilience of adult populations. Numerous studies of larval dispersal, and associated settlement and recruitment processes, have examined the relationship between population connectivity and oceanographic features. However, relatively little is known about spatial and temporal variation in the abundance of larvae settling among different reefs and the extent to which the species assemblage of larvae settling at one location is reflective of the assemblage in neighbouring areas. Here, using crest nets, which provide a non-selective measure of the total abundance and assemblage of larvae settling to a reef (i.e. larval supply), we collected larval coral reef fishes at five locations surrounding two spatially disparate French Polynesian islands: Moorea and Nengo-Nengo. Overall, larval settlement patterns were correlated with the lunar cycle, with larval abundance peaking during the new moon. Although there were some spatial differences in larval supply among the five monitored sites, settlement patterns were largely consistent, even at the species level, irrespective of factors such as coastline orientation or distance between sites. This study provides further insights into the mechanisms driving patterns of dispersal and settlement of larval fishes over large spatial scales

Assessment of ecological status of the lagoon of Bora-Bora Island (French Polynesia)

International audienceIn the South Pacific, an important island has been forgotten and neglected from monitoring and research programs on marine biodiversity: Bora-Bora, often called the ‘Pearl of the Pacific’. To fill this gap in our knowledge, we have analyzed the only two datasets available to date on the biodiversity of Bora-Bora’s reefs: Reef Checks’ program, conducted on 18 sites inside the lagoon in 2006 and 2018; and Biodiversity’s monitoring program, conducted on 31 lagoon sites in 2019. Both monitoring programs showed that the corals in Bora-Bora lagoon are in good health. The living coral cover has been stable on all recorded geomorphological zones between 2006 and 2019. In contrast, there was a strong decrease in the density of all macro-invertebrate species recorded (i.e. giant clams, sea-urchins, sea-cucumbers, sea-snails). For giant clams, three human-related causes of extraction were identified: collecting activities of tourists, local inhabitants and occasional major predation by large groups of people visiting from other islands for local festivities. Lastly, both monitoring programs showed that all commercial families (i.e. Acanthuridae, Scaridae, Serranidae) increased in density over time. This may be because the larval recruitment of fish seems to be sufficient to offset the loss of adults from local fishing. Overall, our monitoring programs, conducted on coral, macro-invertebrates and fish, suggest that the luxury tourism industry developed at Bora-Bora contributed to the maximization of the economic and social benefits of coral reefs while preserving Bora-Bora’s natural sites, ecosystems and the socio-cultural balance

Boat noise prevents soundscape-based habitat selection by coral planulae

Understanding the relationship between coral reef condition and recruitment potential is vital for the development of effective management strategies that maintain coral cover and biodiversity. Coral larvae (planulae) have been shown to use certain sensory cues to orient towards settlement habitats (e.g. the odour of live crustose coralline algae - CCA). However, the influence of auditory cues on coral recruitment, and any effect of anthropogenic noise on this process, remain largely unknown. Here, we determined the effect of protected reef (MPA), exploited reef (non-MPA) soundscapes, and a source of anthropogenic noise (boat) on the habitat preference for live CCA over dead CCA in the planula of two common Indo-Pacific coral species (Pocillopora damicornis and Acropora cytherea). Soundscapes from protected reefs significantly increased the phonotaxis of planulae of both species towards live CCA, especially when compared to boat noise. Boat noise playback prevented this preferential selection of live CCA as a settlement substrate. These results suggest that sources of anthropogenic noise such as motor boat can disrupt the settlement behaviours of coral planulae. Acoustic cues should be accounted for when developing management strategies aimed at maximizing larval recruitment to coral reefs

Lipoprotein(a) and Benefit of PCSK9 Inhibition in Patients With Nominally Controlled LDL Cholesterol

International audienceBackground: Guidelines recommend nonstatin lipid-lowering agents in patients at very high risk for major adverse cardiovascular events (MACE) if low-density lipoprotein cholesterol (LDL-C) remains ≥70 mg/dL on maximum tolerated statin treatment. It is uncertain if this approach benefits patients with LDL-C near 70 mg/dL. Lipoprotein(a) levels may influence residual risk.Objectives: In a post hoc analysis of the ODYSSEY Outcomes (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) trial, the authors evaluated the benefit of adding the proprotein subtilisin/kexin type 9 inhibitor alirocumab to optimized statin treatment in patients with LDL-C levels near 70 mg/dL. Effects were evaluated according to concurrent lipoprotein(a) levels.Methods: ODYSSEY Outcomes compared alirocumab with placebo in 18,924 patients with recent acute coronary syndromes receiving optimized statin treatment. In 4,351 patients (23.0%), screening or randomization LDL-C was 13.7 mg/dL or ≤13.7 mg/dL; corresponding adjusted treatment hazard ratios were 0.82 (95% CI: 0.72-0.92) and 0.89 (95% CI: 0.75-1.06), with Pinteraction = 0.43.Conclusions: In patients with recent acute coronary syndromes and LDL-C near 70 mg/dL on optimized statin therapy, proprotein subtilisin/kexin type 9 inhibition provides incremental clinical benefit only when lipoprotein(a) concentration is at least mildly elevated. (ODYSSEY Outcomes: Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab; NCT01663402)

Relation of Lipoprotein(a) Levels to Incident Type 2 Diabetes and Modification by Alirocumab Treatment

none1691siOBJECTIVE: In observational data, lower levels of lipoprotein(a) have been associated with greater prevalence of type 2 diabetes. Whether pharmacologic lowering of lipoprotein(a) influences incident type 2 diabetes is unknown. We determined the relationship of lipoprotein(a) concentration with incident type 2 diabetes and effects of treatment with alirocumab, a PCSK9 inhibitor. RESEARCH DESIGN AND METHODS: In the ODYSSEY OUTCOMES trial alirocumab was compared with placebo in patients with acute coronary syndrome. Incident diabetes was determined from laboratory, medication, and adverse event data. RESULTS: Among 13,480 patients without diabetes at baseline, 1,324 developed type 2 diabetes over a median 2.7 years. Median baseline lipoprotein(a) was 21.9 mg/dL. With placebo, 10 mg/dL lower baseline lipoprotein(a) was associated with hazard ratio 1.04 (95% CI 1.02-1.06, P < 0.001) for incident type 2 diabetes. Alirocumab reduced lipoprotein(a) by a median 23.2% with greater absolute reductions from higher baseline levels and no overall effect on incident type 2 diabetes (hazard ratio 0.95, 95% CI 0.85-1.05). At low baseline lipoprotein(a) levels, alirocumab tended to reduce incident type 2 diabetes, while at high baseline lipoprotein(a) alirocumab tended to increase incident type 2 diabetes compared with placebo (treatment-baseline lipoprotein(a) interaction P = 0.006). In the alirocumab group, a 10 mg/dL decrease in lipoprotein(a) from baseline was associated with hazard ratio 1.07 (95% CI 1.03-1.12; P = 0.0002) for incident type 2 diabetes. CONCLUSIONS: In patients with acute coronary syndrome, baseline lipoprotein(a) concentration associated inversely with incident type 2 diabetes. Alirocumab had neutral overall effect on incident type 2 diabetes. However, treatment-related reductions in lipoprotein(a), more pronounced from high baseline levels, were associated with increased risk of incident type 2 diabetes. Whether these findings pertain to other therapies that reduce lipoprotein(a) is undetermined.restrictedSchwartz G.G.; Szarek M.; Bittner V.A.; Bhatt D.L.; Diaz R.; Goodman S.G.; Jukema J.W.; Loy M.; Manvelian G.; Pordy R.; White H.D.; Steg P.G. ODYSSEY OUTCOMES Committees and Investigators: Gregory G Schwartz, Philippe Gabriel Steg, Deepak L Bhatt, Vera A Bittner, Rafael Diaz, Shaun G Goodman, Robert A Harrington, J Wouter Jukema, Michael Szarek, Harvey D White, Andreas M Zeiher, Pierluigi Tricoci, Matthew T Roe, Kenneth W Mahaffey, Jay M Edelberg, Corinne Hanotin, Guillaume Lecorps, Angèle Moryusef, Robert Pordy, William J Sasiela, Jean-François Tamby, Philip E Aylward, Heinz Drexel, Peter Sinnaeve, Mirza Dilic, Renato D Lopes, Nina N Gotcheva, Juan-Carlos Prieto, Huo Yong, Patricio López-Jaramillo, Ivan Pećin, Zeljko Reiner, Petr Ostadal, Margus Viigimaa, Markku S Nieminen, Vakhtang Chumburidze, Nikolaus Marx, Nicolas Danchin, Evangelos Liberopoulos, Pablo Carlos Montenegro Valdovinos, Hung-Fat Tse, Robert Gabor Kiss, Denis Xavier, Doron Zahger, Marco Valgimigli, Takeshi Kimura, Hyo Soo Kim, Sang-Hyun Kim, Andrejs Erglis, Aleksandras Laucevicius, Sasko Kedev, Khalid Yusoff, Gabriel Arturo Ramos López, Marco Alings, Sigrun Halvorsen, Roger M Correa Flores, Andrzej Budaj, Joao Morais, Maria Dorobantu, Yuri Karpov, Arsen D Ristic, Terrance Chua, Jan Murin, Zlatko Fras, Anthony J Dalby, José Tuñón, H Asita de Silva, Emil Hagström, Ulf Landmesser, Chern-En Chiang, Piyamitr Sritara, Sema Guneri, Alexander Parkhomenko, Kausik K Ray, Patrick M Moriarty, Robert Vogel, Bernard Chaitman, Sheryl F Kelsey, Anders G Olsson, Jean-Lucien Rouleau, Maarten L Simoons, Karen Alexander, Chiara Meloni, Robert Rosenson, Eric J G Sijbrands, Pierluigi Tricoci, John H Alexander, Luciana Armaganijan, Akshay Bagai, Maria Cecilia Bahit, J Matthew Brennan, Shaun Clifton, Adam D DeVore, Shalonda Deloatch, Sheila Dickey, Keith Dombrowski, Grégory Ducrocq, Zubin Eapen, Patricia Endsley, Arleen Eppinger, Robert W Harrison, Connie Ng Hess, Mark A Hlatky, Joseph Dedrick Jordan, Joshua W Knowles, Bradley J Kolls, David F Kong, Sergio Leonardi, Linda Lillis, David J Maron, Jill Marcus, Robin Mathews, Rajendra H Mehta, Robert J Mentz, Humberto Graner Moreira, Chetan B Patel, Sabrina Bernardez-Pereira, Lynn Perkins, Thomas J Povsic, Etienne Puymirat, William Schuyler Jones, Bimal R Shah, Matthew W Sherwood, Kenya Stringfellow, Darin Sujjavanich, Mustafa Toma, Charlene Trotter, Sean Van Diepen, Matthew D Wilson, Andrew T Yan, Lilia B Schiavi, Marcelo Garrido, Andrés F Alvarisqueta, Sonia A Sassone, Anselmo P Bordonava, Alberto E Alves De Lima, Jorge M Schmidberg, Ernesto A Duronto, Orlando C Caruso, Leonardo P Novaretto, Miguel Angel Hominal, Oscar R Montaña, Alberto Caccavo, Oscar A Gomez Vilamajo, Alberto J Lorenzatti, Luis R Cartasegna, Gustavo A Paterlini, Ignacio J Mackinnon, Guillermo D Caime, Marcos Amuchastegui, Oscar Salomone, Oscar R Codutti, Horacio O Jure, Julio O E Bono, Adrian D Hrabar, Julio A Vallejos, Rodolfo A Ahuad Guerrero, Federico Novoa, Cristian A Patocchi, Cesar J Zaidman, Maria E Giuliano, Ricardo D Dran, Marisa L Vico, Gabriela S Carnero, Pablo N Guzman, Juan C Medrano Allende, Daniela F Garcia Brasca, Miguel H Bustamante Labarta, Sebastian Nani, Eduardo D S Blumberg, Hugo R Colombo, Alberto Liberman, Victorino Fuentealba, Hector L Luciardi, Gabriel D Waisman, Mario A Berli, Ruben O Garcia Duran, Horacio G Cestari, Hugo A Luquez, Jorge A Giordano, Silvia S Saavedra, Gerardo Zapata, Osvaldo Costamagna, Susana Llois, Jonathon H Waites, Nicholas Collins, Allan Soward, Chris L S Hii, James Shaw, Margaret A Arstall, John Horowitz, Daniel Ninio, James F Rogers, David Colquhoun, Romulo E Oqueli Flores, Philip Roberts-Thomson, Owen Raffel, Sam J Lehman, Constantine Aroney, Steven G M Coverdale, Paul J Garrahy, Gregory Starmer, Mark Sader, Patrick A Carroll, Ronald Dick, Robert Zweiker, Uta Hoppe, Kurt Huber, Rudolf Berger, Georg Delle-Karth, Bernhard Frey, Franz Weidinger, Dirk Faes, Kurt Hermans, Bruno Pirenne, Attilio Leone, Etienne Hoffer, Mathias C M Vrolix, Luc De Wolf, Bart Wollaert, Marc Castadot, Karl Dujardin, Christophe Beauloye, Geert Vervoort, Harry Striekwold, Carl Convens, John Roosen, Emanuele Barbato, Marc Claeys, Frank Cools, Ibrahim Terzic, Fahir Barakovic, Zlatko Midzic, Belma Pojskic, Emir Fazlibegovic, Mehmed Kulić, Azra Durak-Nalbantic, Dusko Vulic, Adis Muslibegovic, Boris Goronja, Gilmar Reis, Luciano Sousa, Jose C Nicolau, Flavio E Giorgeto, Ricardo P Silva, Lilia Nigro Maia, Rafael Rech, Paulo R F Rossi, Maria José A G Cerqueira, Norberto Duda, Renato Kalil, Adrian Kormann, José Antonio M Abrantes, Pedro Pimentel Filho, Ana Priscila Soggia, Mayler O N de Santos, Fernando Neuenschwander, Luiz C Bodanese, Yorghos L Michalaros, Freddy G Eliaschewitz, Maria H Vidotti, Paulo E Leaes, Roberto V Botelho, Sergio Kaiser, Euler Roberto Fernandes Manenti, Dalton B Precoma, Jose C Moura Jorge, Pedro G Silva, Jose A Silveira, Wladmir Saporito, Jose A Marin-Neto, Gilson S Feitosa, Luiz Eduardo F Ritt, Juliana A de Souza, Fernando Costa, Weimar K S B Souza, Helder J L Reis, Leandro Machado, José Carlos Aidar Ayoub, Georgi V Todorov, Fedya P Nikolov, Elena S Velcheva, Maria L Tzekova, Haralambi O Benov, Stanislav L Petranov, Haralin S Tumbev, Nina S Shehova-Yankova, Dimitar T Markov, Dimitar H Raev, Mihail N Mollov, Kostadin N Kichukov, Katya A Ilieva-Pandeva, Raya Ivanova, Maryana Gospodinov, Valentina M Mincheva, Petar V Lazov, Bojidar I Dimov, Manohara Senaratne, James Stone, Jan Kornder, Stephen Pearce, Danielle Dion, Daniel Savard, Yves Pesant, Amritanshu Pandey, Simon Robinson, Gilbert Gosselin, Saul Vizel, Gordon Hoag, Ronald Bourgeois, Anne Morisset, Eric Sabbah, Bruce Sussex, Simon Kouz, Paul MacDonald, Ariel Diaz, Nicolas Michaud, David Fell, Raymond Leung, Tycho Vuurmans, Christopher Lai, Frank Nigro, Richard Davies, Gustavo Nogareda, Ram Vijayaraghavan, John Ducas, Serge Lepage, Shamir Mehta, James Cha, Robert Dupuis, Peter Fong, Sohrab Lutchmedial, Josep Rodes-Cabau, Hussein Fadlallah, David Cleveland, Thao Huynh, Iqbal Bata, Adnan Hameed, Cristian Pincetti, Sergio Potthoff, Monica Acevedo, Arnoldo Aguirre, Margarita Vejar, Mario Yañez, Guillermo Araneda, Mauricio Fernandez, Luis Perez, Paola Varleta, Fernando Florenzano, Laura Huidobro, Carlos A Raffo, Claudia Olivares, Leonardo Nahuelpan, Humberto Montecinos, Jiyan Chen, Yugang Dong, Weijian Huang, Jianzhong Wang, Shi'An Huang, Zhuhua Yao, Xiang Li, Lan Cui, Wenhua Lin, Yuemin Sun, Jingfeng Wang, Jianping Li, Xuelian Zhang, Hong Zhu, Dandan Chen, Lan Huang, Shaohong Dong, Guohai Su, Biao Xu, Xi Su, Xiaoshu Cheng, Jinxiu Lin, Wenxia Zong, Huanming Li, Yi Feng, Dingli Xu, Xinchun Yang, Yuannan Ke, Xuefeng Lin, Zheng Zhang, Zeqi Zheng, Zhurong Luo, Yundai Chen, Chunhua Ding, Yi Zhong, Yang Zheng, Xiaodong Li, Daoquan Peng, Shuiping Zhao, Ying Li, Xuebo Liu, Meng Wei, Shaowen Liu, Yihua Yu, Baiming Qu, Weihong Jiang, Yujie Zhou, Xingsheng Zhao, Zuyi Yuan, Ying Guo, Xiping Xu, Xubo Shi, Junbo Ge, Guosheng Fu, Feng Bai, Weiyi Fang, Xiling Shou, Xiangjun Yang, Jian'An Wang, Meixiang Xiang, Yingxian Sun, Qinghua Lu, Ruiyan Zhang, Jianhua Zhu, Yizhou Xu, Zhongcai Fan, Tianchang Li, Chun Wu, Nicolas Jaramillo, Gregorio Sanchez Vallejo, Diana C Luna Botia, Rodrigo Botero Lopez, Dora I Molina De Salazar, Alberto J Cadena Bonfanti, Carlos Cotes Aroca, Juan Diego Higuera, Marco Blanquicett, Sandra I Barrera Silva, Henry J Garcia Lozada, Julian A Coronel Arroyo, Jose L Accini Mendoza, Ricardo L Fernandez Ruiz, Alvaro M Quintero Ossa, Fernando G Manzur Jatin, Aristides Sotomayor Herazo, Jeffrey Castellanos Parada, Rafael Suarez Arambula, Miguel A Urina Triana, Angela M Fernandez Trujillo, Maja Strozzi, Siniša Car, Melita Jerić, Davor Miličić, Martina Lovrić Benčić, Hrvoje Pintarić, Đeiti Prvulović, Jozica Šikić, Viktor Peršić, Dean Mileta, Kresimir Štambuk, Zdravko Babić, Vjekoslav Tomulic, Josip Lukenda, Stanka Mejic-Krstulovic, Boris Starcevic, Jindrich Spinar, David Horak, Zdenek Velicka, Josef Stasek, David Alan, Vilma Machova, Ales Linhart, Vojtech Novotny, Vladimir Kaucak, Richard Rokyta, Robert Naplava, Zdenek Coufal, Vera Adamkova, Ivo Podpera, Jiri Zizka, Zuzana Motovska, Ivana Marusincova, Premysl Svab, Petr Heinc, Jiri Kuchar, Petr Povolny, Jiri Matuska, Steen H Poulsen, Bent Raungaard, Peter Clemmensen, Lia E Bang, Ole May, Morten Bøttcher, Jens D Hove, Lars Frost, Gunnar Gislason, John Larsen, Peter Betton Johansen, Flemming Hald, Peter Johansen, Jørgen Jeppesen, Tonny Nielsen, Kjeld S Kristensen, Piotr Maria Walichiewicz, Jens D Lomholdt, Ib C Klausen, Peter Kaiser Nielsen, Flemming Davidsen, Lars Videbaek, Mai Soots, Veiko Vahula, Anu Hedman, Üllar Soopõld, Kaja Märtsin, Tiina Jurgenson, Arved Kristjan, Juhani K Airaksinen, Saila Vikman, Heikki Huikuri, Pierre Coste, Emile Ferrari, Olivier Morel, Gilles Montalescot, Jacques Machecourt, Gilles Barone-Rochette, Jacques Mansourati, Yves Cottin, Florence Leclercq, Abdelkader Belhassane, Nicolas Delarche, Franck Boccara, Franck Paganelli, Jérôme Clerc, Francois Schiele, Victor Aboyans, Vincent Probst, Jacques Berland, Thierry Lefèvre, Bernard Citron, Irakli Khintibidze, Tamaz Shaburishvili, Zurab Pagava, Ramaz Ghlonti, Zaza Lominadze, George Khabeishvili, Rayyan Hemetsberger, Kemala Edward, Ursula Rauch-Kröhnert, Matthias Stratmann, Karl-Friedrich Appel, Ekkehard Schmidt, Heyder Omran, Christoph Stellbrink, Thomas Dorsel, Emmanouil Lianopoulos, Hans Friedrich Vöhringer, Roger Marx, Andreas Zirlik, Detlev Schellenberg, Thomas Heitzer, Ulrich Laufs, Christian Werner, Nikolaus Marx, Stephan Gielen, Sebastian Nuding, Bernhard Winkelmann, Steffen Behrens, Karsten Sydow, Mahir Karakas, Gregor Simonis, Thomas Muenzel, Nikos Werner, Stefan Leggewie, Dirk Böcker, Rüdiger Braun-Dullaeus, Nicole Toursarkissian, Michael Jeserich, Matthias Weißbrodt, Tim Schaeufele, Joachim Weil, Heinz Völler, Johannes Waltenberger, Mohammed Natour, Susanne Schmitt, Dirk Müller-Wieland, Stephan Steiner, Lothar Heidenreich, Elmar Offers, Uwe Gremmler, Holger Killat, Werner Rieker, Sotiris Patsilinakos, Athanasios Kartalis, Athanassios Manolis, Dimitrios Sionis, Geargios Chachalis, Ioannis Skoumas, Vasilios Athyros, Panagiotis Vardas, Frangkiskos Parthenakis, Dimitrios Alexopoulos, Georgios Hahalis, John Lekakis, Apostolos Hatzitolios, Sergio R Fausto Ovando, Juan L Arango Benecke, Edgar R Rodriguez De Leon, Bryan P Y Yan, David C W Siu, Tibor Turi, Bela Merkely, Imre Ungi, Geza Lupkovics, Lajos Nagy, András Katona, István Édes, Gábor Müller, Iván Horvath, Tibor Kapin, Zsolt Szigeti, József Faluközy, Mukund Kumbla, Manjinder Sandhu, Sharath Annam, Naveen Reddy Proddutur, Reddy Regella, Rajendra K Premchand, Ajaykumar Mahajan, Sudhir Pawar, Atul D Abhyanakar, Prafulla Kerkar, Ravishankar A Govinda, Abraham Oomman, Dhurjati Sinha, Sachin N Patil, Dhiman Kahali, Jitendra Sawhney, Abhijeet B Joshi, Sanjeev Chaudhary, Pankaj Harkut, Santanu Guha, Sanjay Porwal, Srimannarayana Jujjuru, Ramesh B Pothineni, Minguel R Monteiro, Aziz Khan, Shamanna S Iyengar, Jasprakash Singh Grewal, Manoj Chopda, Mahesh C Fulwani, Aparna Patange, Patil Sachin, Vijay K Chopra, Naresh K Goyal, Rituparna Shinde, Gajendra V Manakshe, Nitin Patki, Sumeet Sethi, Vengatesh Munusamy, Sunil Karna, Sunil Thanvi, Srilakshmi Adhyapak, Chandrakant Patil, Ulhas Pandurangi, Rishabh Mathur, Jugal Gupta, Suhas Kalashetti, Ajit Bhagwat, Bagirath Raghuraman, Shiv Kumar Yerra, Prasant Bhansali, Rohidas Borse, Patil Rahul, Srihari Das, Vinay Kumar, Jabir Abdullakutty, Shireesh Saathe, Priya Palimkar, Shireesh Sathe, Shaul Atar, Michael Shechter, Morris Mosseri, Yaron Arbel, Chorin Ehud, Havakuk Ofer, Chaim Lotan, Uri Rosenschein, Amos Katz, Yaakov Henkin, Adi Francis, Marc Klutstein, Eugenia Nikolsky, Robert Zukermann, Yoav Turgeman, Majdi Halabi, Alon Marmor, Ran Kornowski, Michael Jonas, Offer Amir, Yonathan Hasin, Yoseph Rozenman, Shmuel Fuchs, Vered Zvi, Osamah Hussein, Dov Gavish, Zvi Vered, Yoseph Caraco, Mazen Elias, Naveh Tov, Efrat Wolfovitz, Michael Lishner, Nizar Elias, Giancarlo Piovaccari, Annamaria De Pellegrin, Raffaella Garbelotto, Gabriele Guardigli, Valgimigli Marco, Giovanni Licciardello, Carla Auguadro, Filippo Scalise, Claudio Cuccia, Alessandro Salvioni, Giuseppe Musumeci, Michelle Senni, Paolo Calabrò, Salvatore Novo, Pompilio Faggiano, Marco Metra, Nicoletta B De Cesare, Sergio Berti, Claudio Cavallini, Enrico Puccioni, Marcello Galvani, Maurizio Tespili, Piermarco Piatti, Michela Palvarini, Giuseppe De Luca, Roberto Violini, Alessandro De Leo, Zoran Olivari, Pasquale Perrone Filardi, Maurizio Ferratini, Vittorio Racca, Kazuoki Dai, Yuji Shimatani, Haruo Kamiya, Kenji Ando, Yoshihiro Takeda, Yoshihiro Morino, Yoshiki Hata, Kazuo Kimura, Koichi Kishi, Ichiro Michishita, Hiroki Uehara, Toshinori Higashikata, Atsushi Hirayama, Keiji Hirooka, Yasuji Doi, Satoru Sakagami, Shuichi Taguchi, Akihiro Koike, Hiroyuki Fujinaga, Shinji Koba, Ken Kozuma, Tomohiro Kawasaki, Yujiro Ono, Masatoshi Shimizu, Yousuke Katsuda, Atsuyuki Wada, Toshiro Shinke, Takeshi Kimura, Junya Ako, Kenshi Fujii, Toshiyuki Takahashi, Tomohiro Sakamoto, Koichi Nakao, Yutaka Furukawa, Hiroshi Sugino, Ritsu Tamura, Toshiaki Mano, Masaaki Uematsu, Noriaki Utsu, Kashima Ito, Takuya Haraguchi, Katsuhiko Sato, Yasunori Ueda, Akira Nishibe, Kazuteru Fujimoto, Motomaru Masutani, Jung Han Yoon, Hack-Lyoung Kim, Hun Sik Park, In-Ho Chae, Moo Hyun Kim, Myung Ho Jeong, Seungwoon Rha, Chongjin Kim, Hyo-Soo Kim, Hae Young Kim, Taekjong Hong, Seung-Jea Tahk, Youngkwon Kim, Arija Busmane, Natalija Pontaga, Aldis Strelnieks, Iveta Mintale, Iveta Sime, Zaneta Petrulioniene, Roma Kavaliauskiene, Ruta Jurgaitiene, Gintare Sakalyte, Rimvydas Slapikas, Sigute Norkiene, Nerijus Misonis, Aleksandras Kibarskis, Raimondas Kubilius, Stojko Bojovski, Nensi Lozance, Aleksandar Kjovkaroski, Snezana Doncovska, Tiong Kiam Ong, Sazzli Kasim, Oteh Maskon, Balachandran Kandasamy, Houng B Liew, Wan Mohd Izani Wan Mohamed, Armando García Castillo, Jorge Carrillo Calvillo, Pedro Fajardo Campos, Juan Carlos Núñez Fragoso, Edmundo Alfredo Bayram Llamas, Marco Antonio Alcocer Gamba, Jaime Carranza Madrigal, Luis Gerardo González Salas, Enrique López Rosas, Belinda González Díaz, Eduardo Salcido Vázquez, Alfredo Nacoud Ackar, Guillermo Antonio Llamas Esperón, Carlos Rodolfo Martínez Sánchez, María Guerrero De Leon, Rodrigo Suarez Otero, Guillermo Fanghänel Salmón, Jesús Antonio Pérez Ríos, José Angel Garza Ruíz, Robert W Breedveld, Margriet Feenema-Aardema, Alida Borger-Van Der Burg, Pieter A M Hoogslag, Harry Suryapranata, Antonius Oomen, Paulus Van Haelst, Jacobijne J Wiersma, Dirk Basart, Ruud M A Van Der Wal, Peter Zwart, Pascalle Monraats, Henricus Van Kesteren, Ioannis Karalis, Johan Jukema, Gerardus J E Verdel, Bart R G Brueren, Roland P T Troquay, Eric P Viergever, Nadea Y Y Al-Windy, Gerard L Bartels, Jan H Cornel, Walter R M Hermans, Johannes P R Herrman, Robert J Bos, Reginald G E J Groutars, Coenraad C Van Der Zwaan, Refik Kaplan, Raymond Lionarons, Eelko Ronner, Bjorn E Groenemeijer, Patrick N A Bronzwaer, Anho A H Liem, Bernard J W M Rensing, Marcel J J A Bokern, Remco Nijmeijer, Ferry M R J Hersbach, Frank F Willems, Antonius T M Gosselink, Saman Rasoul, John Elliott, Gerard Wilkins, Raewyn Fisher, Douglas Scott, Hamish Hart, Ralph Stewart, Scott Harding, Ian Ternouth, Nicholas Fisher, Samuel Wilson, Denise Aitken, Russell Anscombe, Laura Davidson, Tadeusz Tomala, Ottar Nygård, Jon Arne Sparby, Kjell Andersen, Lars Gullestad, Jarle Jortveit, Peter S Munk, Erlend Gyllensten Singsaas, Ulf Hurtig, Jorge R Calderon Ticona, Julio R Durand Velasquez, Sandra A Negron Miguel, Enrique S Sanabria Perez, Jesus M Carrion Chambilla, Carlos A Chavez Ayala, Reynaldo P Castillo Leon, Rolando J Vargas Gonzales, Jose D Hernandez Zuniga, Luis A Camacho Cosavalente, Jorge E Bravo Mannucci, Javier Heredia Landeo, Nassip C Llerena Navarro, Yudy M Roldan Concha, Víctor E Rodriguez Chavez, Henry A Anchante Hernandez, Carlos A Zea Nunez, Walter Mogrovejo Ramos, Arthur Ferrolino, Rosa Allyn G Sy, Louie Tirador, Rody G Sy, Generoso Matiga, Raul Martin Coching, Alisa Bernan, Gregorio Rogelio, Dante D Morales, Edgar Tan, Dennis Jose Sulit, Adrian Wlodarczak, Krystyna Jaworska, Grzegorz Skonieczny, Lidia Pawlowicz, Pawel Wojewoda, Benita Busz-Papiez, Janusz Bednarski, Aleksander Goch, Pawel Staneta, Elzbieta Dulak, Krzysztof Saminski, Wlodzimierz Krasowski, Wanda Sudnik, Aleksander Zurakowski, Marcin Skorski, Beata Miklaszewicz, Jacek Kubica, Jan Andrzej Lipko, Edyta Kostarska-Srokosz, Marek Piepiorka, Anna Drzewiecka, Ryszard Sciborski, Arkadiusz Stasiewski, Tomasz Blicharski, Leszek Bystryk, Michal Szpajer, Marek Korol, Tomasz Czerski, Ewa Mirek-Bryniarska, Jacek Gniot, Andrzej Lubinski, Jerzy Gorny, Edward Franek, Grzegorz Raczak, Hanna Szwed, Pedro Monteiro, Jose Mesquita Bastos, Helder H Pereira, Dinis Martins, Filipe Seixo, Carlos Mendonça, Ana Botelho, Francisca Caetano, Bogdan Minescu, Octavian Istratoaie, Dan N Tesloianu, Gabriel Cristian, Silviu Dumitrescu, Cristian G C Podoleanu, Mircea C A Constantinescu, Cristina M Bengus, Constantin Militaru, Doina Rosu, Irinel R Parepa, Adrian V Matei, Tom M Alexandru, Mihaela Malis, Ioan Coman, Rodica Stanescu-Cioranu, Doina Dimulescu, Yury Shvarts, Olga Orlikova, Zhanna Kobalava, Olga L Barbarash, Valentin Markov, Nadezhda Lyamina, Alexander Gordienko, Konstantin Zrazhevsky, Alexander Y Vishnevsky, Victor Gurevich, Raisa Stryuk, Nikita V Lomakin, Igor Bokarev, Tatiana Khlevchuk, Sergey Shalaev, Larisa Khaisheva, Petr Chizhov, Inna Viktorova, Natalya Osokina, Vladimir Shchekotov, Evgenia Akatova, Galina Chumakova, Igor Libov, Mikhail I Voevoda, Tatyana V Tretyakova, Evgeny Baranov, Sergey Shustov, Sergey Yakushin, Ivan Gordeev, Niiaz Khasanov, Olga Reshetko, Tatiana Sotnikova, Olga Molchanova, Konstantin Nikolaev, Liudmila Gapon, Elena Baranova, Zaur Shogenov, Elena Kosmachova, Yuriy Karpov, Anton Povzun, Liudmila Egorova, Vadim V Tyrenko, Igor G Ivanov, Masterov Ilya, Sergey Kanorsky, Dragan Simic, Nikola Ivanovic, Goran Davidovic, Nebojsa Tasic, Milika R Asanin, Stevo Stojic, Svetlana R Apostolovic, Stevan Ilic, Biljana Putnikovic Tosic, Aleksandar Stankovic, Aleksandra Arandjelovic, Slavica Radovanovic, Branislava Todic, Jovan Balinovac, Dragan V Dincic, Petar Seferovic, Ana Karadzic, Slobodan Dodic, Sinisa Dimkovic, Tamara Jakimov, Kian-Keong Poh, Hean Yee Ong, Justin Tang I-Shing, Karol Micko, Jan Nociar, Daniel Pella, Peter Fulop, Marian Hranai, Juraj Palka, Juraj Mazur, Ivan Majercák, Andrej Dzupina, František Fazekas, Jozef Gonsorcik, Viliam Bugan, Juraj Selecky, Gabriel Kamensky, Jaroslava Strbova, Rudolf Smik, Andrej Dukat, Peter Olexa, Ivan Žuran, Janez Poklukar, Nataša Černič Šuligoj, Matija Cevc, Henry P Cyster, Naresh Ranjith, Clive Corbett, Junaid Bayat, Ellen Makoali Makotoko, Hendrik du Toit Theron, Ilse E Kapp, Matthys M de V Basson, Hanlie Lottering, Dina Van Aswegen, Louis J Van Zyl, Peter J Sebastian, Thayabran Pillay, Jan A Saaiman, Patrick J Commerford, Soraya Cassimjee, Garda Riaz, Iftikhar O Ebrahim, Mahomed Sarvan, Joseph H Mynhardt, Helmuth Reuter, Rajendran Moodley, Manuel Vida, Angel R Cequier Fillat, Vicente Bodí Peris, Francisco Fuentes Jimenez, Francisco Marín, Jose M Cruz Fernández, Rafael Jesus Hidalgo Urbano, Blas Gil-Extremera, Pablo Toledo, Fernando Worner Diz, David Garcia-Dorado, Andres Iñiguez, José Tuñón Fernández, Jose R Gonzalez-Juanatey, Javier Fernandez Portales, Fernando Civeira Murillo, Laia Matas Pericas, Jose Luis Zamorano, Manuel De Mora Martin, Jordi Bruguera Cortada, Joaquin J Alonso Martin, Jose Maria Serrano Antolin, José R De Berrazueta Fernández, José Antonio Vázquez de Prada, Jose Francisco Díaz Fernández, José Alberto García Lledó, Juan Cosín Sal

Variational approximation for importance sampling and statistical inference on social influence

Monte Carlo methods are widely used in statistical computing area to solve different problems. Social network analysis plays an importance role in many fields. In this dissertation, we focus on improving the efficiency of importance sampling, detecting the degrees of influence in networks, and exploring properties of generalized Erd\H{o}s-R\'enyi model. In the first part of the thesis, we propose an importance sampling algorithm with proposal distribution obtained from variational approximation. This method combines the strength of both importance sampling and the variational method. On one hand, this method avoids the bias from variational approximation. On the other hand, variational approximation provides a way to design the proposal distribution for the importance sampling algorithm. Theoretical justification of the proposed method is provided. Numerical results show that using variational approximation as the proposal can improve the performance of importance sampling and sequential importance sampling. In the second part of the thesis, we propose a sequential hypothesis testing procedure to detect the degrees of influence in a network. We build a multivariate Bernoulli model to represent the status of each node in the network with different degrees of influence. A double bootstrap strategy is used to resolve the uncertainty from by estimating nuisance parameters in hypothesis testing. Theoretical justification of the proposed method is provided to show that the hypothesis testing is powerful for larger networks. Simulation studies show that our method can preserve the levels and improve the powers in hypothesis testing. We also apply our proposed method on two real network data to explore the degree of influence for various features. In the third part of the thesis, we propose a random graph model for undirected networks with small-world properties, namely with a high clustering coefficient and a low average path length. We generalize the regular Erd\H{o}s-R\'enyi dyadic random graph by considering higher-order motif, which is triadic graph. We show some properties of our proposed model, analyze the probability of multi-edges, and compare the local clustering coefficient with ER model. In addition, we also provide some conditions about phase transition including connectivity threshold and the existence of giant components