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Cues
Kinds of Cues Terms modified by Cues Selected AbstractsCarbon use efficiency depends on growth respiration, maintenance respiration, and relative growth rate.PLANT CELL & ENVIRONMENT, Issue 9 2003A case study with lettuce ABSTRACT Carbon use efficiency (CUE, the ratio between the amount of carbon incorporated into dry matter to the amount of carbon fixed in gross photosynthesis) is an important parameter in estimating growth rate from photosynthesis data or models. It previously has been found to be relatively constant among species and under different environmental conditions. Here it is shown that CUE can be expressed as a function of the relative growth rate (rGR) and the growth (gr) and maintenance respiration coefficients (mr): 1/CUE = 1 + gr + mr/rGR. Net daily carbon gain (Cdg), rGR, and CUE were estimated from whole-plant gas exchange measurements on lettuce (Lactuca sativa L.) ranging from 24 to 66 d old. Carbon use efficiency decreased from 0.6 to 0.2 with increasing dry mass, but there was no correlation between CUE and Cdg. The decrease in CUE with increasing dry mass was correlated with a simultaneous decrease in rGR. From the above equation, gr and mr were estimated to be 0.48 mol mol,1 and 0.039 g glucose g,1 dry matter d,1, respectively. Based on the gr estimate, the theoretical upper limit for CUE of these plants was 0.68. The importance of maintenance respiration in the carbon balance of the plants increased with increasing plant size. Maintenance accounted for 25% of total respiration in small plants and 90% in large plants. [source] CUE,REACTIVITY IN RODENTS,HOW PREDICTABLE?ADDICTION, Issue 10 2009MOHAMMED SHOAIB No abstract is available for this article. [source] Growth and maintenance respiration for individual plants in hierarchically structured canopies of Medicago sativa and Helianthus annuus: the contribution of current and old assimilatesNEW PHYTOLOGIST, Issue 2 2004Markus Lötscher Summary ,,Respiratory costs of Medicago sativa and Helianthus annuus individuals growing in hierarchically structured stands in a controlled environment were analysed with regard to the daily rate of carbon (C) assimilation. ,,Net assimilation of new C (An, g C d,1) and respiration rates of new (Rnew, g C d,1) and old C (Rold, g C d,1) were assessed by 13CO2 labelling and gas exchange measurements. ,,Specific respiration rate of old C (rold, g C g,1 C d,1) decreased exponentially with increasing shoot biomass, but was not affected by the instantaneous relative growth rate (,wi). The growth coefficient g (Rnew: An) was c. 0.32. In the most severely shaded subordinate plants, g was < 0.2, but low g stimulated rold. The contribution of Rnew to total respiraton (fR, new) and the carbon use efficiency CUE (1 , R/(An +Rnew)) were c. 0.68 and 0.62 for ,wi > 0.1, respectively. For ,wi < 0.1, fR, new and CUE decreased with decreasing ,wi in both dominant and subordinate plants. ,,The results suggest that Rold was closely related to maintenance, whereas Rnew was primarily involved in growth. [source] Carbon use efficiency depends on growth respiration, maintenance respiration, and relative growth rate.PLANT CELL & ENVIRONMENT, Issue 9 2003A case study with lettuce ABSTRACT Carbon use efficiency (CUE, the ratio between the amount of carbon incorporated into dry matter to the amount of carbon fixed in gross photosynthesis) is an important parameter in estimating growth rate from photosynthesis data or models. It previously has been found to be relatively constant among species and under different environmental conditions. Here it is shown that CUE can be expressed as a function of the relative growth rate (rGR) and the growth (gr) and maintenance respiration coefficients (mr): 1/CUE = 1 + gr + mr/rGR. Net daily carbon gain (Cdg), rGR, and CUE were estimated from whole-plant gas exchange measurements on lettuce (Lactuca sativa L.) ranging from 24 to 66 d old. Carbon use efficiency decreased from 0.6 to 0.2 with increasing dry mass, but there was no correlation between CUE and Cdg. The decrease in CUE with increasing dry mass was correlated with a simultaneous decrease in rGR. From the above equation, gr and mr were estimated to be 0.48 mol mol,1 and 0.039 g glucose g,1 dry matter d,1, respectively. Based on the gr estimate, the theoretical upper limit for CUE of these plants was 0.68. The importance of maintenance respiration in the carbon balance of the plants increased with increasing plant size. Maintenance accounted for 25% of total respiration in small plants and 90% in large plants. [source] RESPONSES TO SMOKING CUES ARE RELEVANT TO SMOKING AND RELAPSEADDICTION, Issue 10 2009SAUL SHIFFMAN No abstract is available for this article. [source] CUES MUST INCREASE SMOKING BEHAVIOUR TO BE CLINICALLY RELEVANTADDICTION, Issue 10 2009KENNETH A. PERKINS No abstract is available for this article. [source] PLASTICITY TO LIGHT CUES AND RESOURCES IN ARABIDOPSIS THALIANA: TESTING FOR ADAPTIVE VALUE AND COSTSEVOLUTION, Issue 6 2000Lisa A. Dorn Abstract Plants shaded by neighbors or overhead foliage experience both a reduction in the ratio of red to far red light (R:FR), a specific cue perceived by phytochrome, and reduced photosynthetically active radiation (PAR), an essential resource. We tested the adaptive value of plasticity to crowding and to the cue and resource components of foliage shade in the annual plant Arabidopsis thaliana by exposing 36 inbred families from four natural populations to four experimental treatments: (1) high density, full sun; (2) low density, full sun; (3) low density, neutral shade; and (4) low density, low R:FR-simulated foliage shade. Genotypic selection analysis within each treatment revealed strong environmental differences in selection on plastic life-history traits. We used specific contrasts to measure plasticity to density and foliage shade, to partition responses to foliage shade into phytochrome-mediated responses to the R:FR cue and responses to PAR, and to test whether plasticity was adaptive (i.e., in the same direction as selection in each environment). Contrary to expectation, we found no evidence for adaptive plasticity to density. However, we observed both adaptive and maladaptive responses to foliage shade. In general, phytochrome-mediated plasticity to the R:FR cue of foliage shade was adaptive and counteracted maladaptive growth responses to reduced PAR. These results support the prediction that active developmental responses to environmental cues are more likely to be adaptive than are passive resource-mediated responses. Multiple regression analysis detected a few costs of adaptive plasticity and adaptive homeostasis, but such costs were infrequent and their expression depended on the environment. Thus, costs of plasticity may occasionally constrain the evolution of adaptive responses to foliage shade in Arabidopsis, but this constraint may differ among environments and is far from ubiquitous. [source] CONSUMER ASSESSMENT OF THE SAFETY OF RESTAURANTS: THE ROLE OF INSPECTION NOTICES AND OTHER INFORMATION CUESJOURNAL OF FOOD SAFETY, Issue 4 2006SPENCER HENSON ABSTRACT This paper explores the ways in which consumers assess the safety of food in restaurants and other eating-out establishments, and the resulting impact on restaurant choice. The analysis builds on the existing literature on restaurant choice more generally and a growing body of studies on the impact of official inspection information on the perceived safety of restaurants. Based on a two-stage consumer study in the City of Hamilton in Ontario, Canada, involving focus groups and a postal survey, the research highlights how consumers base their assessment of food safety in restaurants using a range of visible indicators of the experience and/or credence characteristics associated with foodborne illness. These include their observed judgments of restaurant hygiene, the overall quality of the restaurant, external information, including official inspection certificates, and the level of patronage. The use of these broad groups of indicators varies across consumer subgroups according to gender, age, level of education and recollections of past incidences when a restaurant was closed and/or convicted for food safety reasons. [source] When What You See Isn't What You Get: Alcohol Cues, Alcohol Administration, Prediction Error, and Human Striatal DopamineALCOHOLISM, Issue 1 2009Karmen K. Yoder Background:, The mesolimbic dopamine (DA) system is implicated in the development and maintenance of alcohol drinking; however, the exact mechanisms by which DA regulates human alcohol consumption are unclear. This study assessed the distinct effects of alcohol-related cues and alcohol administration on striatal DA release in healthy humans. Methods:, Subjects underwent 3 PET scans with [11C]raclopride (RAC). Subjects were informed that they would receive either an IV Ringer's lactate infusion or an alcohol (EtOH) infusion during scanning, with naturalistic visual and olfactory cues indicating which infusion would occur. Scans were acquired in the following sequence: (1) Baseline Scan: Neutral cues predicting a Ringer's lactate infusion, (2) CUES Scan: Alcohol-related cues predicting alcohol infusion in a Ringer's lactate solution, but with alcohol infusion after scanning to isolate the effects of cues, and (3) EtOH Scan: Neutral cues predicting Ringer's, but with alcohol infusion during scanning (to isolate the effects of alcohol without confounding expectation or craving). Results:, Relative to baseline, striatal DA concentration decreased during CUES, but increased during EtOH. Conclusion:, While the results appear inconsistent with some animal experiments showing dopaminergic responses to alcohol's conditioned cues, they can be understood in the context of the hypothesized role of the striatum in reward prediction error, and of animal studies showing that midbrain dopamine neurons decrease and increase firing rates during negative and positive prediction errors, respectively. We believe that our data are the first in humans to demonstrate such changes in striatal DA during reward prediction error. [source] THE ROLE OF AUDITORY CUES IN MODULATING THE PERCEIVED CRISPNESS AND STALENESS OF POTATO CHIPSJOURNAL OF SENSORY STUDIES, Issue 5 2004MASSIMILIANO ZAMPINI ABSTRACT We investigated whether the perception of the crispness and staleness of potato chips can be affected by modifying the sounds produced during the biting action. Participants in our study bit into potato chips with their front teeth while rating either their crispness or freshness using a computer-based visual analog scale. The results demonstrate that the perception of both the crispness and staleness was systematically altered by varying the loudness and/or frequency composition of the auditory feedback elicited during the biting action. The potato chips were perceived as being both crisper and fresher when either the overall sound level was increased, or when just the high frequency sounds (in the range of 2 kHz,20 kHz) were selectively amplified. These results highlight the significant role that auditory cues can play in modulating the perception and evaluation of foodstuffs (despite the fact that consumers are often unaware of the influence of such auditory cues). The paradigm reported here also provides a novel empiric methodology for assessing such multisensory contributions to food perception. [source] UNEQUAL ATTENDANCE: THE RELATIONSHIPS BETWEEN RACE, ORGANIZATIONAL DIVERSITY CUES, AND ABSENTEEISMPERSONNEL PSYCHOLOGY, Issue 4 2007DEREK R. AVERY Although prior evidence has demonstrated racial differences in employee absenteeism, no existing research explains this phenomenon. The present study examined the roles of 2 diversity cues related to workplace support,perceived organizational value of diversity and supervisor,subordinate racial/ethnic similarity,in explicating this demographic difference among 659 Black, White, and Hispanic employees of U.S. companies. Blacks reported significantly more absences than their White counterparts, but this difference was significantly more pronounced when employees believed their organizations placed little value on diversity. Moreover, in a form of expectancy violation, the Black,White difference was significant only when employees had racially similar supervisors (and thus would expect their companies to value diversity) and perceived that the organization placed little value on diversity. [source] Decomposition Cascades of Dicoordinate Copper(I) ChalcogenidesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 33 2007Heiko Jacobsen Abstract Cu,E, Si,E, and Cu,P bond energies of R3PCuESiR3 and CuESiR3 complexes (E = O, S, Se) have been investigated using PBE density-functional calculations, and including empirical corrections for dispersive interactions (DFT-D). The bond energies have been used to investigate likely pathways of molecular decomposition. The energy profile for thermal decomposition is to a large degree independent of the nature of the phosphane ligands and silyl groups. Oxides, sulfides, and selenides have qualitatively the same thermal decomposition profile. Thermal decomposition is not likely to produce copper chalcogenide units CuE, but elemental copper Cu instead. Consideration of intermolecular van der Waals attraction suggests that the linear geometry of system tBu3PCuOSiPh3 as found in the crystal is most likely due to crystal packing and intermolecular forces.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Haptic Cues for Image DisambiguationCOMPUTER GRAPHICS FORUM, Issue 3 2000G. Faconti Haptic interfaces represent a revolution in human computer interface technology since they make it possible for users to touch and manipulate virtual objects. In this work we describe a cross-model interaction experiment to study the effect of adding haptic cues to visual cues when vision is not enough to disambiguate the images. We relate the results to those obtained in experimental psychology as well as to more recent studies on the subject. [source] The Importance of Visual Cues for Nocturnal Species: Eagle Owl Fledglings Signal with White Mouth FeathersETHOLOGY, Issue 10 2007Vincenzo Penteriani Complex begging display by bird offspring has predominantly been investigated in diurnal species, which have conspicuous gape colours or plumage features. In nocturnal species, in contrast, such visual communication has received little attention because the assumption is that they exclusively rely on vocal communication. Here, we use a field experiment to investigate whether eagle owls, Bubo bubo, communicate through visual signals at night. We artificially decreased the brightness of the white feathers surrounding fledgling eagle owls' mouths during the post-fledging dependence period, and investigated the effect of this treatment by comparing the condition of these birds to that of birds who received a control treatment. Several physiological parameters considered in our analyses indicate that control owlets were in better condition than owlets with brightness-reduced mouth feathers, which suggests that they received more or better food from feeding parents who discriminated between those young. Brightness-dependent reactions of parent owls suggest that visual signalling may be more widely employed than previously thought, and studying birds at night may reveal sophisticated strategies of animal communication. [source] Multiple Cues in Status Signalling: The Role of Wingbars in Aggressive Interactions of Male House SparrowsETHOLOGY, Issue 10 2006Veronika Bókony During aggressive interactions, animals may signal their competitive ability by various ornaments referred to as badges of status. The use of a single badge predicting dominance rank occurs in many vertebrate species. However, animals often display multiple ornaments that may convey information about either different or the same aspects of the signaller's quality, or alternatively, may serve as signal amplifiers. We observed the fighting behaviour of male house sparrows in two captive flocks to investigate whether they may use multiple cues in status signalling during aggressive interactions. Beside the status-signalling bib, male sparrows possess a conspicuous white wingbar that they often display upon aggressive encounters. We tested whether bib size and the wingbar's conspicuousness (i.e. its achromatic contrast with the neighbouring dark feathers) or its area predicted success in various aspects of fighting. We found that bib size strongly predicted overall fighting success (i.e. proportion of fights won) and defence success (i.e. proportion of successful defences out of all attacks received). Wingbar conspicuousness was positively related to defence success after controlling for the effect of bib size in multivariate analyses. Furthermore, displaying the wings also tended to improve the birds' success in defence but not in attack. Wingbar area was unrelated to any measured aspect of fighting ability. We suggest that bib size and wingbar conspicuousness may convey multiple messages on fighting abilities, specifically on overall aggressiveness and defending potential, respectively. Alternatively, wingbars may serve as amplifiers for the wing displays of aggressive motivation. Thus, male sparrows may use multiple cues in assessing the competitive ability of opponents during social interactions. [source] Female Attraction to Conspecific Chemical Cues in the Palmate Newt Triturus helveticusETHOLOGY, Issue 8 2005Jean Secondi Although chemosignals are largely used in sexual communication in urodeles, olfactometer studies in newts provided contrasting results about the sex specificity of female behavioural responses. Because long-range sexual advertisement is believed to be costly, some species might restrain this activity to close interactions with conspecifics. We tested chemical-mediated sexual attraction in female palmate newt (Triturus helveticus) by measuring the attraction to male and female odours in a linear water olfactometer. Unexpectedly, females were attracted towards conspecifics regardless of sex. They did not show attraction towards Limnaea stagnalis, a common sympatric aquatic gastropod. These results do not support the use of long-range male sexual signalling in the palmate newt. Instead, conspecific attraction is likely to promote aggregation of males and females in breeding ponds. Observations in the field and in the laboratory tend to support the aggregative behaviour of this species. We discuss the possible function of conspecific attraction in this context. Heading towards any conspecific would increase the probability of finding potential mates. Chemical cues do not need to be sex-specific at that stage so that long-range sexual advertisement might be unnecessary. This work emphasizes the need for studies investigating the evolutionary relationships between sexual signalling systems and population-distribution patterns. [source] Nest Hydrocarbons as Cues for Philopatry in a Paper WaspETHOLOGY, Issue 5 2005A. Sumana Philopatric behavior has been demonstrated in a wide taxonomic spread of animals. In temperate environments, overwintered Polistes wasp foundresses often return to their natal nest prior to initiating colony construction. Previous research has shown that these spring foundresses can identify the natal nest in the absence of landmark and gross morphological cues. Hydrocarbons are essential recognition cues for Polistes nest and nestmate discrimination, but cuticular hydrocarbon profiles can become homogenized when foundresses overwinter in mixed colony groups. We examined the hydrocarbon profiles of Polistes dominulus foundresses and nests before and after an overwintering period, and found that the hydrocarbon profiles of nests remain unique over time and that this uniqueness is influenced by the original foundresses. Our data raise the possibility that in returning to the natal nest, foundresses reacquire their colony-specific signature, which may play a role in the formation of cooperative associations. [source] Homing in German Cockroaches, Blattella germanica (L.) (Insecta: Dictyoptera): Multi-Channelled Orientation CuesETHOLOGY, Issue 10 2004Colette Rivault Cockroaches use navigational cues to elaborate their return path to the shelter. Our experiments investigated how individuals weighted information to choose where to search for the shelter in situations where path integration, visual and olfactory cues were conflicting. We showed that homing relied on a complex set of environmental stimuli, each playing a particular part. Path integration cues give cockroaches an estimation of the position of their goal, visual landmarks guide them to that position from a distance, while olfactory cues indicate the end of the path. Cockroaches gave the greatest importance to the first cues they encountered along their return path. Nevertheless, visual cues placed beyond aggregation pheromone deposits reduced their arrest efficiency and induced search in the area near the visual cues. [source] Population and Species Divergence of Chemical Cues that Influence Male Recognition of Females in Desmognathine SalamandersETHOLOGY, Issue 7 2003Paul Verrell Growing evidence indicates that males may be more discriminating of mating partners than often has been assumed. In the North American Ocoee dusky salamander, Desmognathus ocoee (Plethodontidae: Desmognathinae), sexual incompatibility among conspecific populations is high in encounters staged in the laboratory, at least in part because males fail to recognize ,other' females as appropriate targets for courtship. I used Y-mazes to test the hypothesis that males of D. ocoee discriminate between substrate-borne chemical cues produced by ,own' (homotypic) and ,other' (heterotypic) females. Males of four populations discriminated in favor of substrates soiled by homotypic females over clean (control) substrates (expt 1), suggesting that females produce chemical cues of sociosexual significance to males. Furthermore, males from these populations discriminated in favor of substrates soiled by homotypic females vs. substrates soiled by heterotypic females (expt 2), both conspecific and heterospecific (D. carolinensis and D. orestes). Thus, differences among populations and species in female chemical cues appear to affect the chemotactic responses of males. I suggest that, together with differences in behavioral signals and responses exhibited during courtship, differences in female chemical cues likely contribute to sexual incompatibility among populations and taxa of desmognathine salamanders. [source] Responses of Snow Voles, Chionomys nivalis, Towards Conspecific Cues Reflect Social Organization during Overwintering PeriodsETHOLOGY, Issue 11 2002Juan J. Luque-Larena Among microtine rodents, reaction to chemical cues from conspecifics is assumed to reflect social and spatial relationships. Generally, strong attraction of particular odours correlates with non-aggressive behaviour and high spatial tolerance towards odour donors, whereas weak attraction correlates with greater levels of aggression and spatial segregation. In the present study, we examined whether winter odour preferences of the snow vole Chionomys nivalis, a rock-dwelling microtine principally found at high-mountainous regions, differ from that of other vole species, owing to their different social organization during overwintering periods. The social structure of C. nivalis over the winter period is relatively unusual among vole species in that they become nomadic and solitary. In odour choice trials under laboratory conditions, we found that both males and females avoided zones with conspecific odours of both sexes in comparison with unscented control zones or own odours. These results are consistent with the elevated levels of intraspecific aggression and spatial isolation of C. nivalis during overwintering periods. Furthermore, scent-elicited self-grooming increased when their own odour was offered against conspecific cues. This, in combination with an active avoidance of conspecific odours, might functionally contribute to minimize direct confrontations between solitary individuals, thereby reducing the risks of aggressive encounters during overwintering periods. [source] Avoidance of Chemical Alarm Cues Released from Autotomized Tails of Ravine Salamanders (Plethodon richmondi)ETHOLOGY, Issue 4 2001Jeffery A. Hucko The ability of animals to detect and avoid areas containing chemical alarm cues from conspecifics is well documented in aquatic species. The ability to detect chemical alarm cues in terrestrial organisms has not been tested until recently. In this study, we tested the ability of the ravine salamander (Plethodon richmondi) to detect and avoid areas containing chemicals released from the autotomized tails of conspecifics and sympatric zigzag salamanders (P. dorsalis). We also ascertained whether any avoidance response could be attributed to the size or sex of the animal. Our results suggest that ravine salamanders avoid substrates containing odors released from the autotomized tails of conspecifics, but not of heterospecific salamanders and that this response occurs independent of the size and/or sex of the animal. By avoiding areas where a conspecific has recently been injured, an organism could reduce its chances of encountering a predator and thus increase its chances of survival. [source] The representation of Kanizsa illusory contours in the monkey inferior temporal cortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 10 2008Gy. Sáry Abstract Stimulus reduction is an effective way to study visual performance. Cues such as surface characteristics, colour and inner lines can be removed from stimuli, revealing how the change affects recognition and neural processing. An extreme reduction is the removal of the very stimulus, defining it with illusory lines. Perceived boundaries without physical differences between shape and background are called illusory (or subjective) contours. Illusory and real contours activate early stages of the macaque visual pathway in similar ways. However, data relating to the processing of illusory contours in higher visual areas are scarce. We recently reported how illusory contours based on abutting-line gratings affect neurones in the monkey inferotemporal cortex, an area essential for object and shape vision. We now present data on how inferotemporal cortical neurones of monkeys react to another type of shapes, the Kanizsa figures. A set of line drawings, silhouettes, their illusory contour-based counterparts, and control shapes have been presented to awake, fixating rhesus monkeys while single-cell activity was recorded in the anterior part of the inferotemporal cortex. Most of the recorded neurones were responsive and selective to shapes presented as illusory contours. Shape selectivity was proved to be different for line drawings and illusory contours, and also for silhouettes and illusory contours. Neuronal response latencies for Kanizsa figures were significantly longer than those for line drawings and silhouettes. These results reveal differences in processing for Kanizsa figures and shapes having real contours in the monkey inferotemporal cortex. [source] Lunar cycles and reproductive activity in reef fishes with particular attention to rabbitfishesFISH AND FISHERIES, Issue 4 2004Akihiro Takemura Abstract Cues from the moon influence synchrony in growth, feeding, migration, behaviour and reproduction of many reef fishes. Compared with comprehensive studies on the annual and daily activities of fish, few physiological studies have paid attention to the importance of lunar cues in reproductive activities. We review mutual and interesting relationships between fish reproduction and environmental changes induced by the moon, with particular emphasis on the reproductive activity of the rabbitfishes (Siganidae). Rabbitfish species exhibit, in nature, a definitive reproductive season, which differs among the tropical areas. During the reproductive season, synchronous spawning of rabbitfish is associated with a particular lunar phase. The lunar phase used by the respective species is similar in different regions on the earth. Histological observations revealed that gonads develop synchronously towards a peak around the spawning lunar phase, after which the gonads return to spent condition. Concomitant with gonadal development, sex steroid hormones were produced under the influence of gonadotropin (GtH). Injections of human chronic gonadotropin (hCG) to the fish that are undergoing active spermatogenesis accelerated testicular maturation. These results suggest that hormonal response in maturing the gonads in rabbitfish is under the regulation of GtH, and that pituitary secretion of GtH according to the lunar cycle accounts for the lunar rhythm in gonadal development. We speculate that the cues from the moon can be recognized by the higher parts of the hypothalamus,pituitary,gonadal axis. Possible relationships between exogenous environmental factors and the lunar-reproductive rhythm are also discussed. [source] Multiple predator-avoidance behaviours of the freshwater snail Physella heterostropha pomila: responses vary with riskFRESHWATER BIOLOGY, Issue 3 2000Thomas M. McCarthy Summary 1We examined the predator-avoidance behaviour, exhibited in response to chemical cues, of two populations of the snail Physella heterostropha pomila. Snails were subjected to four treatments simulating different degrees of predation risk: control water (low risk), or water from tanks containing nonforaging crayfish (intermediate risk), crushed conspecifics (high risk) or crayfish consuming conspecifics (high risk). Data were analysed using three-way ANOVA models (population × predator chemicals × injured conspecific chemicals). 2Physella increased its avoidance behaviour as risk increased. Crayfish cue elicited a significantly greater response than from controls. Cues from injured conspecifics elicited the strongest response. 3Physella exhibited several types of avoidance behaviour, including burial into the substratum, moving to the water surface, and crawling out of the water. The type of cue present influenced response type. Cues from crayfish reduced burial and increased movement to the water surface or out of the water. Cues from injured-conspecifics significantly increased crawling completely out of the water. 4The two populations differed in the type and degree of response exhibited. One population exhibited significantly greater ,reactivity' (i.e. any avoidance behaviour) in response to foraging crayfish, and more burial and crawl-out behaviours were exhibited in high-risk treatments. [source] Mechanical Gradient Cues for Guided Cell Motility and Control of Cell Behavior on Uniform SubstratesADVANCED FUNCTIONAL MATERIALS, Issue 18 2009Barbara Cortese Abstract A novel method for the fabrication and the use of simple uniform poly(dimethylsiloxane) PDMS substrates for controlling cell motility by a mechanical gradient is reported. The substrate is fabricated in PDMS using soft lithography and consists of a soft membrane suspended on top of a patterned PDMS substrate. The difference in the gradient stiffness is related to the underlying pattern. It is shown experimentally that these uniform substrates can modulate the response of cell motility, thus enabling patterning on the surfaces with precise cell motility. Because of the uniformity of the substrate, cells can spread equally and a directional movement to stiffer regions is clearly observed. Varying the geometry underlying the membrane, cell patterning and movement can be quantitatively characterized. This procedure is capable of controlling cell motility with high fidelity over large substrate areas. The most significant advance embodied in this method is that it offers the use of mechanical features to control cell adhesion and not topographical or chemical variations, which has not been reported so far. This modulation of the response of cell motility will be useful for the design and fabrication of advanced planar and 3D biological assemblies suitable for applications in the field of biotechnology and for tissue-engineering purposes. [source] The Development of Affect Specificity in Infants' Use of Emotion CuesINFANCY, Issue 5 2008Nicole Gendler Martin This study examined the emergence of affect specificity in infancy. In this study, infants received verbal and facial signals of 2 different, negatively valenced emotions (fear and sadness) as well as neutral affect via a television monitor to determine if they could make qualitative distinctions among emotions of the same valence. Twenty 12- to 14-month-olds and 20 16- to 18-month-olds were examined. Results suggested that younger infants showed no evidence of referential specificity, as they responded similarly to both the target and distracter toys, and showed no evidence of affect specificity, showing no difference in play between affect conditions. Older infants, in contrast, showed evidence both of referential and affect specificity. With respect to affect specificity, 16- to 18-month-olds touched the target toy less in the fear condition than in the sad condition and showed a larger proportion of negative facial expressions in the sad condition versus the fear condition. These findings suggest a developmental emergence after 15 months of age for affect specificity in relating emotional messages to objects. [source] Relevance of Cues for Assessing Hallucinated Voice ExperiencesINTERNATIONAL JOURNAL OF NURSING TERMINOLOGIES AND CLASSIFICATION, Issue 3 2003Margaret England PhD PURPOSE. To assess psychiatric nurses' views of the importance of itemized content represented on an Inventory of Voice Experiences (IVE) for ongoing assessment of atypical auditory sense perception in people who hear voices. METHODS. Over 6 months, 317 experienced psychiatric nurses rated 58 assessment cues for hallucinated voice experiences. Cronbach's alpha, Cohen's kappa, and Bartko's intraclass correlation coefficients were used to measure concordance of the nurses' judgments against two hypothetical standards derived for purposes of the study. FINDINGS. There was moderate support for both the internal consistency of the nurses' judgments concerning the importance of itemized content represented on the WE and overall equivalence of the content. There was modest-to-moderate concordance of the nurses' original and subsequent judgments but a lack of concordance of the nurses' judgments with equally weighted judgments of the principal investigator even though the judgments of the investigator were based on extant literature and published reports of voice hearers. CONCLUSIONS. Results may reflect the effects of repeated testing, but it also is possible that some nurses did not have enough knowledge or professional experience to quantify judgments about the importance of hallucinated voice descriptions tied to the items on the WE. The findings are being used to refine the IVE. PRACTICE IMPLICATIONS. Findings provide nurses with opportunities for discerning specific characteristics, antecedents, and consequences of voice hearing along with their implications for health and well-being. Discernment of this information will facilitate identification of more specific and meaningful options for helping voice hearers manage their voices. Search terms: Auditory hallucinations, schizophrenia [source] A Novel Mitogen-Activated Protein Kinase Gene in Maize (Zea mays), ZmMPK3, is Involved in Response to Diverse Environmental CuesJOURNAL OF INTEGRATIVE PLANT BIOLOGY, Issue 5 2010Jinxiang Wang In search for components of mitogen-activated protein kinase (MAPK) cascades in maize (Zea mays) involved in response to abscisic acid (ABA) stimulus, a novel MAPK gene, ZmMPK3, from ABA-treated maize leaves cDNA was isolated and characterized. The full length of the ZmMPK3 gene is 1 520 bp and encodes a 376 amino acid protein with a predicted molecular mass of 43.5 kD and a pI of 5.83. ZmMPK3 contains all 11 MAPK conserved subdomains and the phosphorylation motif TEY. Amino acid sequence alignment revealed that ZmMPK3 shared high identity with group-A MAPK in plants. A time course (30,360 min) experiment using a variety of signal molecules and stresses revealed that the transcripts level of ZmMPK3 accumulated markedly and rapidly when maize seedlings were subjected to exogenous signaling molecules: ABA, H2O2, jasmonic acid and salicylic acid, various abiotic stimuli such as cold, drought, ultraviolet light, salinity, heavy metal and mechanical wounding. Its transcription was also found to be tissue-specific regulated. Here, we show that ABA and H2O2 induced a significant increase in the ZmMPK3 activity using immunoprecipitation and in-gel kinase assay. Furthermore, the results showed that the ZmMPK3 protein is localized mainly to the nucleus. These results suggest that the ZmMPK3 may play an important role in response to environmental stresses. [source] Ethical Considerations for Administering Alcohol or Alcohol Cues to Treatment-Seeking Alcoholics in a Research Setting: Can the Benefits to Society Outweigh the Risks to the Individual?ALCOHOLISM, Issue 9 2009A commentary in the context of the National Advisory Council on Alcohol Abuse, Alcoholism, Recommended Council Guidelines on Ethyl Alcohol Administration in Human Experimentation (2005) First page of article [source] When What You See Isn't What You Get: Alcohol Cues, Alcohol Administration, Prediction Error, and Human Striatal DopamineALCOHOLISM, Issue 1 2009Karmen K. Yoder Background:, The mesolimbic dopamine (DA) system is implicated in the development and maintenance of alcohol drinking; however, the exact mechanisms by which DA regulates human alcohol consumption are unclear. This study assessed the distinct effects of alcohol-related cues and alcohol administration on striatal DA release in healthy humans. Methods:, Subjects underwent 3 PET scans with [11C]raclopride (RAC). Subjects were informed that they would receive either an IV Ringer's lactate infusion or an alcohol (EtOH) infusion during scanning, with naturalistic visual and olfactory cues indicating which infusion would occur. Scans were acquired in the following sequence: (1) Baseline Scan: Neutral cues predicting a Ringer's lactate infusion, (2) CUES Scan: Alcohol-related cues predicting alcohol infusion in a Ringer's lactate solution, but with alcohol infusion after scanning to isolate the effects of cues, and (3) EtOH Scan: Neutral cues predicting Ringer's, but with alcohol infusion during scanning (to isolate the effects of alcohol without confounding expectation or craving). Results:, Relative to baseline, striatal DA concentration decreased during CUES, but increased during EtOH. Conclusion:, While the results appear inconsistent with some animal experiments showing dopaminergic responses to alcohol's conditioned cues, they can be understood in the context of the hypothesized role of the striatum in reward prediction error, and of animal studies showing that midbrain dopamine neurons decrease and increase firing rates during negative and positive prediction errors, respectively. We believe that our data are the first in humans to demonstrate such changes in striatal DA during reward prediction error. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||