Passive Prey Discrimination in Surface Predatory Behaviour of Bait-Attracted White Sharks from Gansbaai, South Africa

5noopenBetween the years 2008 and 2013, six annual research expeditions were carried out at Dyer Island (Gansbaai, South Africa) to study the surface behaviour of white sharks in the presence of two passive prey: tuna bait and a seal-shaped decoy. Sightings were performed from a commercial cage-diving boat over 247 h; 250 different white sharks, with a mean total length (TL) of 308 cm, were observed. Of these, 166 performed at least one or more interactions, for a total of 240 interactions with bait and the seal-shaped decoy. In Gansbaai, there is a population of transient white sharks consisting mainly of immature specimens throughout the year. Both mature and immature sharks preferred to prey on the seal-shaped decoy, probably due to the dietary shift that occurs in white sharks whose TL varies between 200 cm and 340 cm. As it is widely confirmed that white sharks change their diet from a predominantly piscivorous juvenile diet to a mature marine mammalian diet, it is possible that Gansbaai may be a hunting training area and that sharks show a discriminate food choice, a strategy that was adopted by the majority of specimens thanks to their ability to visualize energetically richer prey, after having been attracted by the odorous source represented by the tuna bait.openMicarelli, Primo; Chieppa, Federico; Pacifico, Antonio; Rabboni, Enrico; Reinero, Francesca RomanaMicarelli, Primo; Chieppa, Federico; Pacifico, Antonio; Rabboni, Enrico; Reinero, Francesca Roman

Spermatozoa capture HIV-1 through heparan sulfate and efficiently transmit the virus to dendritic cells

Semen is the main vector for HIV-1 dissemination worldwide. It contains three major sources of infectious virus: free virions, infected leukocytes, and spermatozoa-associated virions. We focused on the interaction of HIV-1 with human spermatozoa and dendritic cells (DCs). We report that heparan sulfate is expressed in spermatozoa and plays an important role in the capture of HIV-1. Spermatozoa-attached virus is efficiently transmitted to DCs, macrophages, and T cells. Interaction of spermatozoa with DCs not only leads to the transmission of HIV-1 and the internalization of the spermatozoa but also results in the phenotypic maturation of DCs and the production of IL-10 but not IL-12p70. At low values of extracellular pH (∼6.5 pH units), similar to those found in the vaginal mucosa after sexual intercourse, the binding of HIV-1 to the spermatozoa and the consequent transmission of HIV-1 to DCs were strongly enhanced. Our observations support the notion that far from being a passive carrier, spermatozoa acting in concert with DCs might affect the early course of sexual transmission of HIV-1 infection

ANALISI DEL COMPORTAMENTO PREDATORIO SU PREDE PASSIVE DEI GRANDI SQUALI BIANCHI IN SUD AFRICA

Il presente lavoro di tesi si basa su osservazioni del comportamento predatorio dello squalo bianco Carcharodon carcharias effettuate negli anni 2008- 2012 durante spedizioni appositamente organizzate nella Riserva Naturale di Dyer Island, in Sud Africa dall’Unità di Studio e Ricerca sugli Squali bianchi del Centro Studi Squali dell’Aquarium Mondo Marino di Massa Marittima e sponsorizzata dall’Associazione Posidonia, l’Università della Calabria e di Siena. La riserva comprende due isole (Geyser Rock e Dyer Island), che ospitano un’importante popolazione di otarie del Capo (Arctocephalus pusillus pusillus) che, assieme a pinguini e varie specie di uccelli, costituiscono prede preferenziali per gli squali bianchi. Le osservazioni, effettuate da un’imbarcazione apposita dotata anche di gabbia antisqualo per l’osservazione dall’acqua, si sono concentrate sui differenti moduli predatori di superficie (Martin. 2003, Micarelli et al. 2006, Sperone et al 2012) che si manifestano in presenza di due tipi di prede passive (Micarelli et al. 2006): un’esca di tonno (“bait”) e uno zimbello riproducente la sagoma di un piccolo di otaria. L’attività di ricerca è stata indirizzata a valutare: • La presenza di differenti moduli comportamentali in individui dei due sessi e in individui maturi e immaturi, valutando il grado di variabilità interindividuale nei comportamenti esibiti. • La possibile preferenza mostrata degli squali tra i due tipi di esca presentati, valutando se gli animali esibivano una vera e propria scelta alimentare o eseguivano attacchi indiscriminati verso i due obiettivi

Prijedor, Bosnia. Making Sense of Emptiness. Un workshop, e una prima analisi etnosemiotica, negli spazi urbani del post-conflitto

Presentazione di analisi e osservazione etno-semiotica svolta sul campo, in occasione di un workshop organizzato presso la città di Prijedor, in Bosnia; sul tema della memoria e del post-conflitto

Erratum to: Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition) (Autophagy, 12, 1, 1-222, 10.1080/15548627.2015.1100356

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