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91.
Knowledge of the mechanisms that regulate courtship and mating behavior in Psyttalia concolor (Szépligeti)–a koinobiont endophagous solitary parasitoid of the olive fruit fly, Bactrocera oleae (Rossi), and of other fruit flies–is essential to its mass rearing and management. Augmentative releases of P. concolor for olive fruit fly control started in the Mediterranean areas in the 1950s and still continue with limited success. We determined the influence of visual and chemical cues on courtship and mating behavior of this braconid and the possible effect of the mating status of males and females in the perception of these cues. Our results suggest that integration of visual and chemical stimuli are fundamental for mate location and courtship. Indeed, the optimal response of the male was achieved when physical and chemical cues were simultaneously presented and vision and olfaction worked synergistically. 相似文献
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Giovanni Benelli Elisa Donati Donato Romano Giacomo Ragni Gabriella Bonsignori Cesare Stefanini Angelo Canale 《Insect Science》2016,23(6):869-880
Variations in male body size are known to affect inter‐ and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor affecting signal strength and mate choice. We evaluated the effect of male size on courtship displays and mating success of the olive fruit fly, Bactrocera oleae (Diptera: Tephritidae). Wing vibrations performed during successful and unsuccessful courtships by large and small males were recorded by high‐speed videos and analyzed through frame‐by‐frame analysis. Mating success of large and small males was investigated. The effect of male–male competition on mating success was evaluated. Male body size affected both male courtship signals and mating outcomes. Successful males showed wing‐borne signals with high frequencies and short interpulse intervals. Wing vibrations displayed by successful large males during copulation attempt had higher frequencies over smaller males and unsuccessful large males. In no‐competition conditions, large males achieved higher mating success with respect to smaller ones. Allowing large and small males to compete for a female, large males achieve more mating success over smaller ones. Mate choice by females may be based on selection of the larger males, able to produce high‐frequency wing vibrations. Such traits may be indicative of “good genes,” which under sexual selection could means good social‐interaction genes, or a good competitive manipulator of conspecifics. 相似文献
95.
96.
Maurizio G. Paoletti Robert J. Blakemore Csaba Csuzdi Luca Dorigo Angelo Leandro Dreon Federico Gavinelli Francesca Lazzarini Nicola Manno Enzo Moretto David Porco Enrico Ruzzier Vladimiro Toniello Andrea Squartini Giuseppe Concheri Marina Zanardo Javier Alba-Tercedor 《PloS one》2016,11(3)
A new Italian earthworm morphologically close to the similarly large and anecic Eophila tellinii (Rosa, 1888) is described. Distribution of Eophila crodabepis sp. nov. extends over 750 km2 from East to West on the Asiago Plateau and Vittorio Veneto Hills, from North to South on mounts Belluno Prealps (Praderadego and Cesen), Asiago, Grappa and onto the Montello foothills. This range abuts that of Eophila tellinii in northern Friuli Venezia Giulia region. Known localities of both E. tellinii and E.crodabepis sp. nov. are mapped. mtDNA barcoding definitively separates the new western species from classical Eophila tellinii (Rosa, 1888). 相似文献
97.
Sensory reweighting is a characteristic of postural control functioning adopted to accommodate environmental changes. The use of mono or binocular cues induces visual reduction/increment of moving room influences on postural sway, suggesting a visual reweighting due to the quality of available sensory cues. Because in our previous study visual conditions were set before each trial, participants could adjust the weight of the different sensory systems in an anticipatory manner based upon the reduction in quality of the visual information. Nevertheless, in daily situations this adjustment is a dynamical process and occurs during ongoing movement. The purpose of this study was to examine the effect of visual transitions in the coupling between visual information and body sway in two different distances from the front wall of a moving room. Eleven young adults stood upright inside of a moving room in two distances (75 and 150 cm) wearing a liquid crystal lenses goggles, which allow individual lenses transition from opaque to transparent and vice-versa. Participants stood still during five minutes for each trial and the lenses status changed every one minute (no vision to binocular vision, no vision to monocular vision, binocular vision to monocular vision, and vice-versa). Results showed that farther distance and monocular vision reduced the effect of visual manipulation on postural sway. The effect of visual transition was condition dependent, with a stronger effect when transitions involved binocular vision than monocular vision. Based upon these results, we conclude that the increased distance from the front wall of the room reduced the effect of visual manipulation on postural sway and that sensory reweighting is stimulus quality dependent, with binocular vision producing a much stronger down/up-weighting than monocular vision. 相似文献
98.
Erinaldo Ubirajara Damasceno dos Santos Géssica Dayane Cordeiro de Lima Micheline de Lucena Oliveira Sandra de Andrade Heráclio Hildson Dornelas Angelo da Silva Sergio Crovella Maria de Mascena Diniz Maia Paulo Roberto Eleutério de Souza/ 《Memórias do Instituto Oswaldo Cruz》2016,111(3):174-180
Polymorphisms in chemokine receptors play an important role in the progression of
cervical intraepithelial neoplasia (CIN) to cervical cancer (CC). Our study examined
the association of CCR2-64I (rs1799864) andCCR5-Δ32
(rs333) polymorphisms with susceptibility to develop cervical lesion (CIN and CC) in
a Brazilian population. The genotyping of 139 women with cervical lesions and 151
women without cervical lesions for the CCR2-64I and
CCR5-Δ32 polymorphisms were performed using polymerase chain
reaction-restriction fragment length polymorphism. The individuals carrying
heterozygous or homozygous genotypes (GA+AA) for CCR2-64I
polymorphisms seem to be at lower risk for cervical lesion [odds ratio (OR) = 0.37, p
= 0.0008)]. The same was observed for the A allele (OR = 0.39, p = 0.0002), while no
association was detected (p > 0.05) with CCR5-Δ32 polymorphism.
Regarding the human papillomavirus (HPV) type, patients carrying the
CCR2-64Ipolymorphism were protected against infection by HPV type
16 (OR = 0.35, p = 0.0184). In summary, our study showed a protective effect
ofCCR2-64I rs1799864 polymorphism against the development of
cervical lesions (CIN and CC) and in the susceptibility of HPV 16 infection. 相似文献
99.
Elaine da Conceição Petronilho Magdalena do Nascimento Rennó Newton Gonçalves Castro Fernanda Motta R. da Silva Angelo da Cunha Pinto 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1069-1078
Analogs of pralidoxime, which is a commercial antidote for intoxication from neurotoxic organophosphorus compounds, were designed, synthesized, characterized, and tested as potential inhibitors or reactivators of acetylcholinesterase (AChE) using the Ellman’s test, nuclear magnetic resonance, and molecular modeling. These analogs include 1-methylpyridine-2-carboxaldehyde hydrazone, 1-methylpyridine-2-carboxaldehyde guanylhydrazone, and six other guanylhydrazones obtained from different benzaldehydes. The results indicate that all compounds are weak AChE reactivators but relatively good AChE inhibitors. The most effective AChE inhibitor discovered was the guanylhydrazone derived from 2,4-dinitrobenzaldehyde and was compared with tacrine, displaying similar activity to this reference material. These results indicate that guanylhydrazones as well as future similar derivatives may function as drugs for the treatment of Alzheimer's disease. 相似文献
100.
Among Tephritidae flies, the females display agonistic behavior to maintain single oviposition sites and reduce larval competition for food. In the olive fruit fly, Bactrocera oleae, female-female aggressive interactions are characterized by reciprocal wing waving, chasing, head butting and boxing with forelegs. Little is known on tephritid aggressive behaviors directed towards natural enemies, with special reference to parasitoids attacking their young instars. In this study, we quantified the aggressive behavior of B. oleae females guarding their oviposition site against the braconid parasitoid Psyttalia concolor. The fly aggressive behavior displayed against the parasitoids was compared that directed towards paper dummies mimicking P. concolor adults. When a P. concolor female came close (<20 mm) to a B. oleae female guarding the oviposition site, the 91.67% of the flies displayed wing-waving, the 63.34% chased the parasitoid, the 45% showed head-butting, while boxing was observed only in the 26.67% of the aggressions. When paper dummies were tested, only the 66.67% of the flies displayed wing-waving, the 8.33% performed chasing, followed by head butting (5.00%) and boxing (3.33%). B. oleae displayed longer aggression bouts towards live wasps over dummies. Overall, this is the first evidence pointing out that tephritid aggressive acts, besides their role in intraspecific interactions, were also highly effective to displace parasitic wasps from the fly oviposition site. Further research on potential consequences on fitness traits arising from the above-discussed behaviors, as well as on parasitoid learning-mediated responses to tephritid aggressions, is urgently required. 相似文献