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Significant Preference (significant + preference)
Selected AbstractsIntersensory redundancy educates selective attention in bobwhite quail embryosDEVELOPMENTAL SCIENCE, Issue 6 2006Robert Lickliter We assessed whether exposure to amodal properties in bimodal stimulation (e.g. rhythm, rate, duration) could educate attention to amodal properties in subsequent unimodal stimulation during prenatal development. Bobwhite quail embryos were exposed to an individual bobwhite maternal call under several experimental and control conditions during the day prior to hatching. Experimental groups received redundant auditory and visual exposure to the temporal features of an individual maternal call followed by unimodal auditory exposure to the same call immediately or after a 2-hr or 4-hr delay. Control groups received (1) the same exposure but in the reverse sequence (unimodal , redundant bimodal), (2) asynchronous bimodal , unimodal, (3) only unimodal exposure, or (4) only bimodal exposure. All experimental groups showed a significant preference for the familiar maternal call over a novel maternal call when tested 2 days after hatching, whereas none of the control groups showed a significant preference for the familiar call. These results indicate that intersensory redundancy can direct attention to amodal properties in bimodal stimulation and educate attention to the same amodal properties in subsequent unimodal stimulation where no intersensory redundancy is available. [source] Odor-mediated patch choice in the parasitoid Venturia canescens: temporal decision dynamicsENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2009Yin-Quan Liu Abstract Parasitoids foraging for hosts in a heterogeneous environment would greatly benefit if they could decide already from a distance in which areas search for resources would be most profitable and to avoid areas of low fitness returns. Interestingly, the temporal dynamics of the decision process in parasitoid patch choice have rarely been investigated. In a Y-tube olfactometer, we tested whether thelytokous and arrhenotokous females of the parasitoid wasp Venturia canescens (Gravenhorst) (Hymenoptera: Ichneumonidae) respond to differences in cues indicating the quality of a host-containing patch and choose more profitable patches. Special attention was given to the time it took females to make their choices (patch choice time) when differences in patch quality were either qualitative (absence vs. presence of hosts and kairomone) or quantitative (various concentrations of hosts and kairomone, and presence of competitors). We found that both thelytokous and arrhenotokous wasps only chose the higher-quality patch based on odor cues when the difference was qualitative. When patches differed only with respect to the number of hosts, or the presence or absence of competing female parasitoids, no significant preference could be found in females of either strain of the parasitoid. In contrast, both the time until females reached the junction of the Y-tube olfactometer (response time) and the time until females decided for either patch (decision time) varied with parasitoid strain and odor treatment. Thelytokous wasps were faster than arrhenotokous wasps in their response time and in their decision time. However, females of both strains responded faster with increasing number of total hosts releasing kairomone. Yet, decision time for patches did not significantly vary as a function of patch quality offered to Venturia wasps. [source] Cardioventilatory Coupling in Resting Human SubjectsEXPERIMENTAL PHYSIOLOGY, Issue 6 2003Y. C. Tzeng In 48 conscious resting subjects we examined the temporal coupling of heart beat timing and the onset of inspiration (cardioventilatory coupling), and the relationship between coupling and spectral indices of autonomic function. Using the proportional Shannon entropy (SH,) of the RI -1 interval (interval between inspiration and the preceding ECG R wave) as a measure of coupling we detected statistically significant coupling in 32 of the 48 subjects. This was confirmed by visual inspection of time series plots of RI intervals, in which coupling was evident as horizontal banding. Coupling resulted in a significant preference for whole number heart rate/respiratory frequency ratios. The strongest coupling was associated with low ventilatory frequency and high heart rate variability in the high (0.15-0.40 Hz) and low (0.04-0.15 Hz) frequency ranges, but was not related to blood pressure variability, or to a spectral measure of baroreflex sensitivity (,-index, low frequency range). There was no difference in coupling strength between males and females. We have previously described cardioventilatory coupling in spontaneously breathing anaesthetised subjects. The current study extends those observations by demonstrating that the qualitative features of coupling seen during anaesthesia are also observed in the conscious state. We conclude that the role of coupling in normal physiological respiratory control needs to be more widely explored. [source] Intake, liveweight gain and feed preference by steers fed combinations of lucerne and Westerwolds ryegrass silagesGRASS & FORAGE SCIENCE, Issue 1 2002E. Charmley Nutritive value and voluntary intake of legumes are generally considered to be higher than those of grasses when ensiled at similar digestibility, although high levels of soluble protein can result in low N utilization by animals and high losses to the environment. The objectives of this experiment were to describe the optimum combination of Westerwolds ryegrass (Lolium multiflorum Lam. cv. Aubade) and lucerne (Medicago sativa L. cv. AC Caribou) silages to maximize liveweight gain of steers fed silage, determine chemical components that are important and ascertain whether steers selected the optimum mixture when given a choice. Both silages contained similar concentrations of dry matter (DM), acid-detergent fibre (ADF) and organic acids, but lucerne silage had higher concentrations of N, soluble-N and ammonia-N. Westerwolds ryegrass silage contained more neutral-detergent fibre (NDF). In a 12-week experiment, voluntary intake by Hereford steers was not influenced when the proportion of the two silages was changed from 1 to 0 in 0·25 increments. However, liveweight gain and feed efficiency increased linearly (P < 0·001) as the proportion of ryegrass silage fed was increased. When preconditioned to either of the two silages, steers showed a significant preference for ryegrass over lucerne (P < 0·05). When conditioned to a mixture of both silages, no preference was elicited. It is suggested that extensive solubilization and deamination of protein in the lucerne silage may have caused the preference for Westerwolds ryegrass silage and the higher liveweight gains on diets containing higher proportions of Westerwolds ryegrass silage. [source] A randomised comparison of oral desmopressin lyophilisate (MELT) and tablet formulations in children and adolescents with primary nocturnal enuresisINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 9 2007H. Lottmann Summary Aims:, Desmopressin is a useful treatment for primary nocturnal enuresis (PNE), a common childhood condition that can persist into adolescence. This open-label, randomised, cross-over study evaluated the preference of children and adolescents with PNE for sublingual desmopressin oral lyophilisate (MELT) vs. tablet treatment, and the efficacy, safety, compliance and ease of use associated with each formulation. In total, 221 patients aged 5,15 years who were already receiving desmopressin tablets were randomised 1 : 1 to receive desmopressin treatment in the order MELT/tablet (n = 110) or tablet/MELT (n = 111) for 3 weeks each. Each formulation was administered in bioequivalent doses (0.2/0.4 mg tablets , 120/240 ,g MELT). Following treatment, patients were questioned regarding treatment preference. Diary card data and 100 mm Visual Analogue Scale scores were also recorded. Results:, Overall, patients preferred the MELT formulation to the tablet (56% vs. 44%; p = 0.112). This preference was age dependent (p = 0.006); patients aged < 12 years had a statistically significant preference for desmopressin MELT (p = 0.0089). Efficacy was similar for both formulations (MELT: 1.88 ± 1.94 bedwetting episodes/week; tablet: 1.90 ± 1.85 episodes/week). Ease of use of both formulations was high. Compliance (, 80%) was 94.5% for MELT patients vs. 88.9% for the tablet (p = 0.059). No serious/severe adverse events were reported. Conclusions:, There was an overall preference for the MELT, and a statistically significant preference for desmopressin MELT in children aged 5,11 years. Desmopressin MELT had similar levels of efficacy and safety at lower dosing levels than the tablet, and therefore facilitates early initiation of PNE treatment in children aged 5,6 years. [source] Aerobic Oxidation of Primary Aliphatic Alcohols to Aldehydes Catalyzed by a Palladium(II) Polyoxometalate CatalystADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 2-3 2010Delina Barats Abstract A hexadecyltrimethylammonium salt of a "sandwich" type polyoxometalate has been used as a ligand to attach a palladium(II) center. This Pd-POM compound was an active catalyst for the fast aerobic oxidation of alcohols. The unique property of this catalyst is its significant preference for the oxidation of primary versus secondary aliphatic alcohols. Since no kinetic isotope effect was observed for the dehydrogenation step, this may be the result of the intrinsically higher probability for oxidation of primary alcohols attenuated by steric factors as borne out by the higher reactivity of 1-octanol versus 2-ethyl-1-hexanol. The reaction is highly selective to aldehyde with little formation of carboxylic acid; autooxidation is inhibited. No base is required to activate the alcohol. The fast reactions appear to be related to the electron-acceptor nature of the polyoxometalate ligand that may also facilitate alcohol dehydrogenation in the absence of base. [source] Perception of the Ebbinghaus illusion in 5- to 8-month-old infantsJAPANESE PSYCHOLOGICAL RESEARCH, Issue 1 2010YUKA YAMAZAKI Abstract The Ebbinghaus illusion is a geometric illusion based on a size-contrast between a central circle and surrounding circles. A central circle surrounded by small inducing circles is perceived as being larger than a central circle surrounded by large inducing circles. In the present study we investigated 5- to 8-month-old infants' perception of the Ebbinghaus illusion using a preferential-looking paradigm. We measured the preference between a central circle surrounded by small inducing circles (overestimated figure) and a central circle surrounded by large inducing circles (underestimated figure). Infants showed a significant preference for the overestimated figure when the central circle was flashing, but not when it was static. Furthermore, there was no preference between the two figures when the central circles were removed. These results suggest that infants' preference reflects their perception of the size illusion of the central circle. There is a possibility that 5- to 8-month-old infants perceive the Ebbinghaus illusion. [source] Ovipositional discrimination by Microplitis rufiventris females between healthy and granulosis virus-infected Spodoptera littoralis larvaeJOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2004E. M. Hegazi Abstract: Ovipositional choice tests by Microplitis rufiventris females (Hym., Braconidae) between granulosis virus-infected (GVI) and non-infected (NI) Spodoptera littoralis larvae (Lep., Noctuidae), were assessed using discriminatory methods for re-isolating the NI and virus-infected hosts after removing the female parasitoid. When M. rufiventris females were given a choice between NI and GVI S. littoralis hosts, the adult females exhibited marked preference (P < 0.01) for the NI (i.e. higher quality) hosts. In this case, M. rufiventris females and S. littoralis GV (SlGV) did not significantly compete for the same type of host larvae and are, generally, compatible. However, when the choice was given between two low qualities of S. littoralis hosts, i.e. virus-free previously parasitized hosts and viral-infected hosts a significant preference (P < 0.01) of the parasitoid females for the GVI larvae was observed. In this case, the parasitoid would be at a disadvantage when competing with GV for the same host. However, the parasitoid could be used as an additional tool for the dissemination of biocontrol viruses within different pest populations, i.e. hosts other than S. littoralis. Importantly, the results showed different strategies of parasitoid female in egg-laying management. When M. rufiventris female was given a choice between healthy and SlGVI hosts, the female deposited more eggs than when she was given a choice between two low qualities of host larvae. The results of the study may have implications in pest management strategies using M. rufiventris and SlGV against S. littoralis larvae. [source] Geographic variation in the function of ornaments in the common yellowthroat Geothlypis trichasJOURNAL OF AVIAN BIOLOGY, Issue 1 2008Peter O. Dunn We used controlled aviary experiments to study the role of male ornaments in male-male competition and female choice in the common yellowthroat Geothlypis trichas, a sexually dichromatic warbler. Previous aviary studies in Wisconsin, USA, indicated that males with larger black facial masks were dominant over males with smaller masks and preferred by females in mate choice experiments. In this study, we replicated those experiments in a population in New York, USA, where male mating success was related more consistently to the size of the yellow bib (throat, breast, and belly) than to the size of the mask. Similar to the study in Wisconsin, we found that males with larger masks were more likely to be dominant in New York, however, we found that males with larger bibs were preferred by females in New York, and there was no significant preference for males with larger masks. These results are consistent with the hypothesis that carotenoid-based ornaments are selected by female choice and melanin-based ornaments are selected by male-male competition. However, the pattern of female choice appears to vary between New York and Wisconsin. This geographic difference could be related to a variety of environmental factors (habitat, carotenoid and parasite abundance) that affect the costs and benefits of choosing males with particular ornaments in each location. [source] The effect of sex and shoal size on shoaling behaviour in Danio rerioJOURNAL OF FISH BIOLOGY, Issue 5 2005N. Ruhl Male and female zebra fish Danio rerio were given choices of shoals that differed in sex and size. Male zebra fish preferred to associate with female shoals over male shoals, but had no preference when given a choice between a mixed-sex shoal and either a male or female shoal. Female zebra fish showed no significant preference when given a choice between male and females shoals, nor between mixed-sex shoals and either male or female shoals. When given choices between shoals of differing size, females preferred to associate with the larger shoal, whether or not they were composed of males or females. Males, however, had no preference for larger shoals over smaller shoals, whether or not they were composed of males or females. These results showed that male zebra fish were capable of distinguishing between males and females solely on the basis of visual cues. Furthermore, these results demonstrated a significant difference between the shoaling choices of male and female zebra fish, which may indicate a difference in the function of shoaling for the two sexes. [source] Differential defoliation of Eucalyptus grandis arises from indiscriminant oviposition and differential larval survivalAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2009M. L. Henery Abstract 1,The influence of six open-pollinated families (OPFs) of Eucalyptus grandis on both the growth and development of larvae and the oviposition preference of a paropsine chrysomelid (Paropsis atomaria) was investigated. The OPFs had previously been identified as differing in their susceptibility to defoliation by P. atomaria in forestry progeny trials. 2,Oviposition preference for resistant and susceptible foliage was tested using binary choice tests. These tests did not demonstrate any significant preference for either resistant or susceptible open-pollinated material indicating that adult host preference for susceptible trees was not a likely cause of differential defoliation. 3,Quantification and analysis of growth and development parameters for all larval stages of P. atomaria showed that feeding on genetic material identified as resistant resulted in a significant reduction of relative growth rate of first instar larvae and an alteration to normal feeding behaviour. There was also a trend towards increased larval mortality on resistant E. grandis. 4,We argue that although the magnitude of these effects was minor, interactions with additional biotic and abiotic sources of mortality in the field have the potential, when magnified over successive generations, to result in significant variation in defoliation of host genotypes in the field. [source] Interactions between the stem-mining weevils Ceutorhynchus napi Gyll. and Ceutorhynchus pallidactylus (Marsh.) (Coleoptera: Curculionidae) in oilseed rapeAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2004Georg Dechert Abstract 1,The rape stem weevil Ceutorhynchus napi Gyll. and the cabbage stem weevil Ceutorhynchus pallidactylus (Marsh.) share the same habitat and food resource within the stems of oilseed rape, Brassica napus L. var. oleifera. Interactions occurring between these two sympatric species on this host were studied under both field and laboratory conditions. 2,The oviposition preference of C. pallidactylus and the within-plant distribution of eggs and larvae were examined in field plots of oilseed rape. Female C. pallidactylus tended to lay their eggs in plants already infested by eggs and larvae of C. napi rather than in uninfested plants. The within-plant distribution of the egg batches of C. pallidactylus did not differ significantly between uninfested plants and those preinfested by C. napi. Ovipositing females of C. napi and C. pallidactylus generally showed a significant preference for plants with larger stem diameter. 3,Laboratory choice tests provided further evidence for the oviposition preference of C. pallidactylus. Females laid significantly more eggs in leaves of plants that had been previously infested by C. napi than in leaves of previously uninfested plants. 4,Larvae of C. pallidactylus showed a significant shift of their feeding niche towards the stem base when feeding in individual plants attacked by both species. This possibly indicates ressource partitioning between C. pallidactylus and C. napi. The within-plant distribution of C. napi larvae was not affected by the simultaneous attack of C. pallidactylus. 5,The size of the head capsule of full-grown larvae of C. napi and C. pallidactylus was not significantly correlated with the diameter of the stem of their host plant or with the number of conspecific larvae within individual plants. [source] Pigment study by Raman microscopy of 23 paintings by the Portuguese artist Henrique Pousão (1859,1884)JOURNAL OF RAMAN SPECTROSCOPY, Issue 11 2007Andreia M. Correia Abstract Twenty-three paintings by Henrique Pousão,a 19th century Portuguese painter,belonging to the collection of Museu Nacional Soares dos Reis, Porto, Portugal, were analysed by Raman microscopy. The fine focus of a 100× objective allowed the visualisation and individual identification of small grains. As a result, thirty-seven compounds, namely, anatase, barium white, basic lead sulfate, brochantite, cadmium red, cadmium yellow, calcium carbonate, carbon-based black, celadonite, chrome green, chrome orange, chrome yellow, cobalt blue, cochineal lake, copper sulfide, emerald green, iron(III) oxyhydroxide, iron(III) oxide, kaolinite, lead antimonate yellow, lead carbonate, lead white, lead sulfate, madder lake, malachite, Prussian blue, quartz, realgar/pararealgar, red lead, rutile, Scheele's green, strontium yellow, ultramarine blue, vermilion, viridian, zinc white and zinc yellow, were identified. Not all these compounds are pigments; some are extenders, others trace components and others probably products of reactions between pigments. Special attention was given to the Raman characterisation of celadonite, chrome orange, basic lead sulfate and lead antimonate yellow. Complementary techniques were used to confirm the identities of certain pigments and to characterise reference samples. Pousão, whose work has not previously been studied spectroscopically, was found to have used a remarkably wide range of pigments over his painting periods, without showing significant preference for any particular set of pigments. Copyright © 2007 John Wiley & Sons, Ltd. [source] Spatial ecology of the mulgara in arid Australia: impact of fire history on home range size and burrow useJOURNAL OF ZOOLOGY, Issue 4 2007G. Körtner Abstract Knowledge about the spatial ecology of small mammals in relation to fire history in arid zones in general and Australia in particular is limited. Here, we report data on the spatial ecology of the brush-tailed mulgara Dasycercus blythi in the hummock grasslands of Uluru , Kata Tjuta National Park during winter 2006, the beginning of the breeding season for this species. About 73% of the study area had been burnt in 2002 and spinifex cover was sparse. Mulgaras Marsupialia: Dasyuridae (six males and three females) were implanted with radio-transmitters and monitored daily for between 6 and 55 days. All mulgaras appeared to use defined home ranges, which overlapped extensively with those of several neighbours. Spatial overlap occurred between as well as within sexes. On average, males (25.5 ha) occupied significantly larger home ranges than females (10.8 ha). Mulgaras used a number of burrows within home ranges and several were used by more than one individual. Moreover, occasionally, two individuals used the same burrow simultaneously. Home ranges and burrows encompassed both mature spinifex Triodia basedowii and open regrowth areas and mulgaras did not exhibit a significant preference for either habitat type. However, three males were killed by introduced-predators and they all lived predominantly in the open regrowth area. We conclude that mulgaras do not select the dense cover of mature spinifex habitat, and might be subjected to increased risk from introduced predators, especially following fire. [source] Prey capture efficiency in brown capuchin monkeys (Cebus apella) is influenced by sex and corpus callosum morphologyAMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2010Kaitlyn Hellner-Burris Abstract The diet of capuchin monkeys consists largely of fruits, but these monkeys commonly prey upon insects and other invertebrates as well as vertebrates such as lizards, birds, and fish. Capturing small fast-moving prey requires the ability to process complex visuospatial information such as motion detection, shape, and pursuit. Here we report the results of an experimental investigation into whether capuchins display sex differences in prey capture efficiency, and whether these differences are associated with the morphology of regions of the corpus callosum (CC) involved in visuospatial ability. We examined the prey capture behavior of seven capuchin subjects (four female, three male) in the laboratory by providing subjects opportunities to fish. Additionally, we obtained structural magnetic resonance images from these subjects to determine if spatial-ability was related to CC anatomy. Over 30 fishing trials, we recorded the number of prey capture attempts, success rate in capturing fish, and hand techniques used in these attempts. Males were significantly faster and more successful than females at capturing prey. In addition, males had smaller total CC:brain ratios than females. Males displayed a left hand bias, as well as significant unimanual usage, whereas females displayed no significant preference for hand usage. Individual capture times were correlated with total CC:brain ratio. Taken together, our results suggest a relationship between prey capture efficiency, sex, and the degree of brain lateralization. Am. J. Primatol. 72:502,508, 2010. © 2010 Wiley-Liss, Inc. [source] Determinants of preferred intertidal feeding habitat for Eastern Curlew: A study at two spatial scalesAUSTRAL ECOLOGY, Issue 2 2007PAUL G. FINN Abstract Broadscale habitat use by Eastern Curlews (Numenius madagascariensis) in their non-breeding range in eastern Australia was assessed using low tide surveys on feeding grounds, where 60 skilled volunteers made repeated counts of the birds on intertidal flats, across 41% (9500 ha) of the intertidal habitat within Moreton Bay, Australia. We analysed 32 defined sections of intertidal flat, of roughly equal area (mostly 200,400 ha), which varied greatly in their curlew density (2,47 birds per 100 ha) and also in substrate and other environmental features. Sites with the least resistant substrates had densities three times those with the most resistant substrates. Of 10 environmental characteristics measured for each site, substrate resistance was the best predictor of curlew density (r2 = 0.45). Characteristics that were poor predictors included distance to the nearest roost, level of human disturbance and distance to urban settlement. For a finer-scale assessment, microhabitat use and feeding behaviour were recorded during low tide within 12 intertidal flats, which varied in size (23,97 ha), substrate, topography and other features. Across all flats, curlews strongly preferred to feed relatively close (0,50 m) to the low-water line. They fed on a variety of substrates (including sand, sandy-mud, mud and seagrass) in broadly similar proportions to their occurrence in the habitat. There was a statistically significant preference for sand, although its magnitude was not strong. These results indicate that curlews select habitat most strongly at a between-flat rather than within-flat scale. [source] Changes in the Vif protein of HIV-1 associated with the development of resistance to inhibitors of viral proteaseJOURNAL OF MEDICAL VIROLOGY, Issue 2 2005Melanie A. Adekale Abstract The protease (PR) and virus infectivity factor (vif) gene sequences of a cohort of HIV-1 infected patients showing evidence of developing protease inhibitor (PI) resistance whilst undergoing highly active antiretroviral therapy (HAART) have been determined. The PR sequences showed the presence of the classical mutations associated with resistance to PIs. The sequence of the Vif protein showed less variation in samples from PI treated patients than in specimens prepared from treatment-naïve patients. In addition a number of amino acid positions within Vif showed highly significant preferences for a particular amino acid in the PI-treated cohort compared to the untreated control cohort. J. Med. Virol. 75:195,201, 2005. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||||||||