761 resultados para Mate poaching


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Several hormonal and physiological changes that occur during pregnancy directly affect gastrointestinal motility (GI), however, very little is known about the relationship between the electrical and mechanical activities of the stomach and its implications. The aim of this study was to compare the female sex hormones, with profiles of gastrointestinal motility using AC biosusceptometry (BAC) in pregnant rats. Seven female Wistar rats (weighing 250-350 g) were used and all procedures were approved by the local Ethics Committee of animal. Laparotomy was performed on anesthetized rats and a magnetic marker (3.5 mm in diameter and 3.0 mm height) was implanted in the distal stomach. After 10 days of recuperation, the mice were put to mate until confirmation of pregnancy. Fed animals were anesthetized (mg pentobarbital 30 / kg) and kept supine for recording the signal with a sensor 30 min BAC placed on the abdominal surface on days 0, 7, 14 and 20 of gestation. Statistical analysis was performed by Student's t test statistical Newman-Keuls and a P value of .05 was considered statistically significant. The frequency of contraction of the stomach was 74 mHz ± 3, 67 ± 7 mHz, 59 mHz ± 6 (p <0.05 vs day -1) and 71 ± 5 mHz on days -0, -7, -14, and -20, respectively. The values of 44 ± 15 pg / mL and 31 ± 9 pg / ml 25 ± 6 pg / ml, 22 ± 9 pg / ml on days -0, -7, -14 and -20, respectively, obtained by 17ß- estradiol were not statistically significant. The values of progesterone were 13 ± 6 pg / ml at 54 ± 15 pg / ml, 127 ± 42 pg / ml (p <0.05 vs day-1), 22 ± 13 pg / mL on day -0, - 7, -14 and -20, respectively. A linear correlation (Pearson's test) between the lower frequency gastric and increased levels of progesterone was 80% (p <0.0000001). Until then, the relationship between changes in motility and hormone were not described in detail, but with the work that we were able to demonstrate the high correlation between progesterone concentration ...

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Homogamy has been suggested as crucial for human mate preferences and mate choice. People are attracted to and choose romantic partners that are similar to them in socio-demographic, physical, and psychological traits. However, only a few studies have shown homogamy in preferences for evolved sex-typical traits. Here, we have investigated male and female preferences for the level of cognitive masculinity-femininity (MF). We tested whether self-reported MF positively correlates with preferences for MF. One hundred men and one hundred women from Brazil filled in questionnaires on their own level of cognitive MF and preferred level of cognitive MF in their ideal partner. Half of the respondents were asked to indicate their preferences for long-term, and the other half for short-term relationships. We found a positive correlation between self-ascribed and preferred level of cognitive MF in women (P = 0.002), but no significant correlation in men (P = 0.309). There was no significant effect of the temporal context of the relationship, but there was a positive correlation between self-ascribed and preferred level of cognitive MF only in women answering about long-term partner. By subtracting the preferred from the selfascribed level of cognitive MF, we created a self-similarity index. We found that women desire potential mates more self-similar and more masculine than men (P < 0.001) and that in men there is greater variation in the self-similarity index than in women. Our results thus add to previous evidence on the role of homogamy in human mating, by showing preferences for self-similarity also in cognitive MF for women, especially for long-term partner preferences. Future studies should cross-culturally test whether the higher self-similar preference found in women is universal.

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The aim of this study is to investigate and analyze the conceptions of sexuality and female sexual behavior and conduct, formed from the merger of information and securities purchased under the eyes, rules and guidelines established relations with the Holy Office during his visit to Inquisitorial Brazil in the late sixteenth century. It is a survey of historical methodology in which we used as the exploratory research and literature. In the sixteenth century the Church increases the pressure to change the sexual mores that were free in the Middle Ages, a fact which influences the rules and regulations that are adopted by the Holy Office regarding the person's sex life. The first structure was based on Brazilian sexual alliance between Indians and settlers, which led to sugar, by the Portuguese, the customs of the land, which included sexual practices free since the Indians were out of Christian influence. Supported by the absence of white women, the settlers took them wives of the earth, usually more than one, creating conflict with the Jesuits who condemned Indian polygamy. In this context, in 1591, landed on Brazilian soil Heitor Furtado de Mendonca, and with it, the First Visitation of the Holy Office to investigate, arguing, exploring feelings and behaviors, to discover the true facts, finally, to demonstrate the errors Faith and punish them with the rigor of ecclesiastical law. His passing opens us to visualize traces of sexuality in the current "Tropic" a racist, misogynist world where black women and degraded land could be subject to the wishes of the white man, with whom he could mate at will. Alone and forgotten, women have not found the colony margin to denounce or to speak and were stigmatized by the look of travelers and writers have been through here.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Mouse embryo production by superstimulation is a multifactorial process. To minimize the number of sacrificed animals and to maximize the results of the superstimulatory treatment, it should be possible to predict the risk of do not get embryos from such a treated animal. This work aimed to evaluate if the variables - hormone concentration and the timing of its administration, the copulatory plug presence and individual male used to mating – could be predictive factors on the mouse embryo production. Females were distributed in four groups (cross-over design) related to scheduled superstimulation treatment (1300h or 1700h) and eCG/hCG administered concentration (5 or 10IU). After the hCG treatment, females were put to mate. On the next morning it was verified the presence of a copulatory plug (D0.5). Embryo recovery was performed from D2.5 to D4.5 by flushing the oviducts and uterine horns. Total structures recovered (TSR) and the viable embryos (VE) were classified by its morphology. Viability rate (VR) was calculated with VE in relation to TSR (x100). Group comparison was analyzed with 5% of significance. There were no significant differences among groups, even when only main effects were analyzed (hormone concentration and timing of its administration). There was significant difference in VR from animals with or without plug and from the worst and best males used. It was concluded that neither the hormone concentration nor timing of its administration - or their association – was significant as predictive factors for the embryo production. However, the plug presence was related to higher VR.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pós-graduação em Educação Escolar - FCLAR

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The turtle retina has been extensively used for the study of chromatic processing mechanisms. Color opponency has been previously investigated with trichromatic paradigms, but behavioral studies show that the turtle has ail ultraviolet (UV) channel and a tetrachromatic visual system. Our laboratory has been working ill the characterization of neuronal responses in the retina of vertebrates using stimuli in the UV-visible range of the electromagnetic spectrum. In the present investigation, we recorded color-opponent responses from turtle amacrine and ganglion cells to UV and visible stimuli and extended our previous results that UV color-opponency is present at the level of the inner nuclear layer. We recorded from 181 neurons, 36 of which were spectrally opponent. Among these, there were 10 amacrine (5%), and 26 ganglion cells (15%). Morphological identification of color-opponent neurons was possible for two ganglion cell classes (G17 and G22) and two amacrine cell classes (A22 and A23b). There was a variety of cell response types and a potential for complex processing of chromatic stimuli, with intensity- and wavelength-dependent response components. Ten types of color opponency were found in ganglion cells and by adding previous results from our laboratory, 12 types of opponent responses have been found. The majority of the ganglion cells were R+UVBG- and RG+UVB-color-opponents but there were other less frequent types of chromatic opponency. This study confirms the participation of a UV channel in the processing of color opponency in the turtle inner retina and shows that the turtle visual system has the retinal mechanisms to allow many possible chromatic combinations.

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The courtship behavior in calopterygid damselflies is well documented; however, the behavior of the large Neotropical genus Mnesarete is still unknown. Thus, here we present the first description of male-female interactions in Mnesarete pudica, a common damselfly in the Neotropical Savanna. The male-female interactions were composed of courtship displays, mounting, and chasing. The courtship behavior lasted 5.23 +/- 1.65 s and is very different from other calopterygids, consisting of hovering flights and the cross display made in front of females rather than on the oviposition site. The arrival and presence of females on a male territory are not sufficient to initiate sexual interactions; the male usually interacts with the female only after a patrolling flight. The females may present three distinct behaviors in response to male approach: (a) warding off signal (31.53%), (b) escape (28.83%), (c) and wing flipping (39.64%), which seems to stimulate male courtship. Females also may sit still, which induces males to react as if females were signaling they are willing to mate. In this paper, we also suggest that male courtship behavior is mediated by female signals.

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Preliminary observations of the harvestman Leiobunum vittatum found that individuals rub their bodies against the substrate, presenting the possibility of chemical marking. To determine whether or not L. vittatum individuals can detect substrate-borne chemical cues, we compared responses of L. vittatum males and females to substrate-borne male and female cues. We found that individuals of L. vittatum do respond to conspecific cues and that their responses are sex-specific. In response to substrate-borne conspecific cues, male L. vittatum spent more time, engaged in more scraping with their sensory legs I, and engaged in pedipalpal tapping more often in the presence versus absence of conspecific cues (male and female equally). Furthermore, in the presence of conspecific cues, males engaged in two behaviors never observed in females-(a) "fast approach" and (b) "jerking", the latter of which was never observed in the presence of cricket cues. In contrast to males, females did not spend more time on conspecific cues, but did spend more time tapping their pedipalps in the presence of male vs female cues, suggesting an ability to distinguish between them. A final experiment explored the possibility that females could discriminate among males of varying histories of agonistic interactions based upon their chemical cues. We found no support for this hypothesis. Our results demonstrate that L. vitattum do respond to conspecific cues, and introduce the possibility that intraspecific communication may be mediated in part by chemical cues.

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We investigated the possibility of reproductive interference between two sibling spider species, Paratrechalea azul and Paratrechalea ornata, which occur syntopically and reproduce synchronously. Males of both species offer a nuptial gift composed of prey wrapped in silk to females. Through laboratory experiments, we evaluated possible asymmetries in the outcome of heterospecific encounters between males and females, and investigated whether chemical signalling could function as a premating barrier between the two species. Males of P. azul were unable to discriminate conspecific from heterospecific female draglines, which resulted in wasted time and energy in nuptial gift construction. Males of P. ornata incurred a higher cost for discrimination mistakes because most of them were attacked by heterospecific females; 95% lost the nuptial gift upon the attack and 33% were preyed upon. This pattern is probably a consequence of differences in body size between males and females of each species. Both species showed erroneous female choice, but only P. ornata females courted heterospecific males, which are considerably larger than conspecific males and may resemble high-quality mating partners. Males of P. ornata also made discrimination mistakes, but at a much lower frequency compared to P. azul males. The selective pressure for precise recognition of conspecific female signs is probably stronger on P. ornata males because misdirected courtship may increase their chances of encountering predatory heterospecific females. This study provides the first detailed evidence of reproductive interference between two reproductively isolated spider species, showing that the costs paid by individuals of different sexes and different species are highly asymmetric. (C) 2012 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

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The effects of pregestational and gestational low-to-moderate physical training on insulin secretion in undernourished mothers were evaluated. Virgin female Wistar rats were divided into four groups as follows: control (C, n = 5); trained (T, n = 5); low-protein diet (LP, n = 5); trained with a low-protein diet (T + LP, n = 5). Trained rats ran on a treadmill over a period of 4 weeks before mate (5 days week(-1) and 60 min day(-1), at 65% of VO2max). At pregnancy, the intensity and duration of the exercise were reduced. Low-protein groups were provided with an 8% casein diet, and controls were provided with a 17% casein diet. At third day after delivery, mothers and pups were killed and islets were isolated by collagenase digestion of pancreas and incubated for a further 1 h with medium containing 5.6 or 16.7 mM glucose. T mothers showed increased insulin secretion by isolated islets incubated with 16.7 mM glucose, whereas LP group showed reduced secretion of insulin by isolated islets when compared with both C and LP + T groups. Physical training before and during pregnancy attenuated the effects of a low-protein diet on the secretion of insulin, suggesting a potential role for compensation of insulin resistance and preventing gestational diabetes mellitus.