bluuebunny/crossref_metadata_2025_split huggingface dataset:
Activation Timecourse of Ventral Visual Stream Object-recognition Areas: High Density Electrical Mapping of Perceptual Closure Processes
Authors: Doniger Glen M. , Foxe John J. , Murray Micah M. , Higgins Beth A. , Snodgrass Joan Gay , Schroeder Charles E. , Javitt Daniel C. 
Published: July 2002

Abstract
Object recognition is achieved even in circumstances when only partial information is available to the observer. Perceptual closure processes are essential in enabling such recognitions to occur. We presented successively less fragmented images while recording high-density event-related potentials (ERPs), which permitted us to monitor brain activity during the perceptual closure processes leading up to object recognition. We reveal a bilateral ERP component (Ncl) that tracks these processes (onsets ∼ 230 msec, maximal at ∼290 msec). Scalp-current density mapping of the Ncl revealed bilateral occipito-temporal scalp foci, which are consistent with generators in the human ventral visual stream, and specifically the lateral-occipital or LO complex as defined by hemodynamic studies of object recognition.
Electrophysiological Correlates of the Retrieval of Emotional and Non-emotional Context
Authors: Maratos Elizabeth J. , Rugg Michael D. 
Published: July 2002

Abstract
In two experiments, words were presented in negatively or neutrally valenced sentences. At test, subjects made old/new recognition judgments to these words. In Experiment 2 only, for words judged old, subjects also indicated whether the words had been studied in a neutral or a negative context. In Experiment 1, left parietal old/new event-related brain potential (ERP) effects were larger and more sustained when elicited by words that had been studied in negative sentences, and a right frontal old/new effect was elicited by these words exclusively. In Experiment 2, the left parietal and right frontal effects elicited by old words correctly assigned to their study context were equivalent in size regardless of the nature of the context; a third ERP old/new effect, maximal over posterior scalp regions, was seen only for words from negative contexts. The findings indicate that incidental retrieval of emotional context gives rise to greater activation in neural systems supporting conscious recollection than does retrieval of nonemotional context. When contextual retrieval is intentional, recollection of emotional and non-emotional information are associated with equivalent engagement of these systems. The findings from Experiment 2 suggest that additional neural circuitry may be activated selectively by emotionally valenced episodic information.
An fMRI Study on the Time-Limited Role of the Medial Temporal Lobe in Long-Term Topographical Autobiographic Memory
Authors: Niki Kazuhisa , Luo Jing 
Published: July 2002

Abstract
The time-limited role of the medial temporal lobe (MTL) in human long-term memory is well known. However, there is still no direct neuroimaging evidence to confirm it. In this fMRI study, nine subjects were scanned while asked to recall the places they visited more than seven years ago (remote memories); and the places they visited recently (recent memories). We observed robust and dominant MTL activity peaking in the left parahippocampal gyrus when recent memories were contrasted with remote memories. This result provided direct evidence for the time-limited role of the MTL in long-term topographical autobiographic memory. Further analysis revealed that this MTL activity was not due to the fact that the retrieval of recent memories was accompanied by more details. When detailed recent memories were contrasted with detailed remote memories, there was still MTL activity peaking in the left parahippocampal gyrus. The effects of details in remote memories are also discussed.
Detecting and Estimating Signals in Noisy Cable Structures, II: Information Theoretical Analysis
Authors: Manwani Amit , Koch Christof 
Published: July 2002

This is the second in a series of articles that seek to recast classical single-neuron biophysics in information-theoretical terms. Classical cable theory focuses on analyzing the voltage or current attenuation of a synaptic signal as it propagates from its dendritic input location to the spike initiation zone. On the other hand, we are interested in analyzing the amount of information lost about the signal in this process due to the presence of various noise sources distributed throughout the neuronal membrane. We use a stochastic version of the linear one-dimensional cable equation to derive closed-form expressions for the second-order moments of the fluctuations of the membrane potential associated with different membrane current noise sources: thermal noise, noise due to the random opening and closing of sodium and potassium channels, and noise due to the presence of “spontaneous” synaptic input. We consider two different scenarios. In the signal estimation paradigm, the time course of the membrane potential at a location on the cable is used to reconstruct the detailed time course of a random, band-limited current injected some distance away. Estimation performance is characterized in terms of the coding fraction and the mutual information. In the signal detection paradigm, the membrane potential is used to determine whether a distant synaptic event occurred within a given observation interval. In the light of our analytical results, we speculate that the length of weakly active apical dendrites might be limited by the information loss due to the accumulated noise between distal synaptic input sites and the soma and that the presence of dendritic nonlinearities probably serves to increase dendritic information transfer.
WHY DID NOAH SEND OUT A RAVEN?
Authors:   Moberly
Published: July 2002

AbstractA survey of ancient and modern interpretations of Genesis viii 7 reveals the consistent assumption that the raven must perform the same function as the dove, which makes the presence of the raven puzzling - why two birds? Traditional commentators explain the raven in symbolic and moralizing terms, while modern commentators generally see it as a traditio-historical fragment. It is here proposed that the raven has a different task from that of the dove, in that its flying to and fro above the waters is a symbolic replication of God's action through the ruah (Genesis viii 1) whereby the waters recede. This is related to the concept of imitatio Dei in Priestly thought.
THE DISTRIBUTION OF GROOMING AMONG FEMALE PRIMATES: TESTING HYPOTHESES WITH THE SHANNON-WIENER DIVERSITY INDEX
Authors: Di Bitetti Mario S. 
Published: July 2002

AbstractThe Shannon-Wiener diversity index (H) has been used to characterize grooming relationships among adult female primates. To make comparisons among different groups, the value of H has been divided by the maximum value it can reach for a particular group size. This ratio, the grooming diversity ratio (GDR), has been used to test predictions from hypotheses that may explain the distribution of social relationships among adult female primates. Using grooming data from different primate populations and random computer simulations I show that the mean value of H and GDR are positively affected by the ln of the mean number of grooming bouts recorded per dyad (LnMNBD) and negatively by the coefficient of variation in the frequency of grooming bouts recorded for the females within a group (CV). These two variables reflect the combined effect of sampling effort and the rate of interactions among individuals (and their variance) and should be statistically controlled to make sensible use of H or GDR. After controlling for LnMNBD and CV, I found no significant effect of female group size, the degree of female involvement in inter-group encounters and the patterns of female dispersal on the mean value of GDR. The socioecological model of female social relationships (Sterck et al., 1997) predicts that groups categorized as resident-egalitarian should have higher GDRs than resident-nepotistic ones. I find some support for this prediction when using a data set where some species contributed more than one data point but not when using mean values per species as in the previous analyses. This result may be confounded by a phylogenetic effect: langurs seem to have more diverse relationships than other primates. Data from more species are necessary to corroborate these results and to disentangle the effect of phylogeny from that of the social categories since most monkey groups characterized as resident-egalitarian were langurs.
BEHAVIOUR OF DOMESTIC PIGS IN A VISUAL PERSPECTIVE TAKING TASK
Authors: Held Suzanne , Mendl Michael , Devereux Claire , Byrne Richard 
Published: July 2002

Abstract
Animals with visual perspective taking abilities should differ in their responses to individuals that do and individuals that do not have visual access to some critical event. We investigated whether domestic pigs show behaviour consistent with this ability. Ten subjects were trained to move from a start box into one of four corridors that they had seen a human enter with a bucket for baiting. They received a food reward for choosing the correct corridor. In unrewarded probe tests, the subjects' view of the corridors was blocked, but they could see a 'seeing' companion pig who had visual access to the baiting event, and another, whose view was also blocked, located in start boxes to their left and right. After the companions had been released and entered corridors, the subject was released and which companion it followed was recorded. Eight pigs followed companions less frequently than expected by chance, probably due to specific corridor or centre/side preferences. However, one subject showed no positional bias, and a significant preference for following the 'seeing' companion, consistent with the ability to take another's visual perspective. Our design rules out learning of a correct response during the experiment, by testing subjects in unrewarded probe trials, and by using companions that were equally trained and unaware of the subject's task. However, we cannot rule out the possibility that previously learned contingencies were used to solve the problem. We therefore consider that this apparent visual perspective taking ability does not necessarily imply any ability to understand knowledge states.
SILK MEDIATED DEFENSE BY AN ORB WEB SPIDER AGAINST PREDATORY MUD-DAUBER WASPS
Authors: Blackledge Todd , Wenzel John 
Published: July 2002

AbstractStabilimenta are zigzag and spiral designs of seemingly conspicuous silk included at the centers of many spider webs. We examined the association of stabilimenta with the ability of spiders to defend themselves against predatory mud-dauber wasps. We found that Argiope trifasciata (Araneae, Araneidae) were significantly more likely to survive attacks by Chalybion caeruleum and Sceliphron caementarium (Hymenoptera, Sphecidae) when spiders included stabilimenta in webs. This association could not be explained by factors such as differences in sizes or conditions of spiders nor locations of webs. We suggest that stabilimenta may function to delay pursuit of spiders as they drop from webs by physically blocking wasps, camouflaging spiders or distracting attacking wasps. Stabilimenta may function in a role very similar to the retreats built by many other genera of spiders and appear to be an adaptation to reduce the predation pressure faced by spiders that have evolved foraging habits at highly exposed diurnal web sites.
SEXUAL HARASSMENT AS A COST FOR MOLLY FEMALES: BIGGER MALES COST LESS
Authors: Schlupp Ingo , McKnab Ryan , Ryan Michael 
Published: July 2002

AbstractFemales of many species receive male attention that reflects a conflict between the sexes over reproduction. Here we demonstrate that female sailfin mollies (Poecilia latipinna) suffer such a cost via a reduction of their feeding time in the presence of males. Female sailfin mollies spend significantly more time feeding when accompanied by an Amazon molly (P.formosa) or a sailfin molly female than when accompanied by a male sailfin molly. Furthermore, we show that male sexual harassment is size dependent and that small males impose a greater cost on females.
HUNGER SUPPRESSES THE ONSET AND THE FREEZING COMPONENT OF THE ANTIPREDATOR RESPONSE TO CONSPECIFIC SKIN EXTRACT IN PINTADO CATFISH
Authors: Giaquinto Percília , Volpato Gilson 
Published: July 2002

Abstract
Although the skin of an injured conspecific releases alarm substance in some fish species, it has been shown that such damage induces feeding behaviour rather than an alarm reaction under conditions of food scarcity. We studied chemical communication associated with this paradox in a Brazilian catfish, the pintado (Pseudoplatystoma coruscans). In preliminary tests pintado were confirmed to demonstrate an alarm reaction to conspecific skin extract. In the experiment we investigated whether skin extract of pintado induces either alarm response (panic or alert component) or feeding in hungry conspecifics. Fish feed-deprived for eight days and fed control fish were exposed to either conspecific skin extract or distilled water (as a control). Alarm reaction was restricted to the skin extract treatment and occurred in the fish irrespective of their hunger state, but the components of this response were significantly affected by hungry. Fed fish showed a complete alarm reaction (dashing and freezing behaviours). Feed-deprived fish exhibited only part of this biphasic response, the dashing component. We conclude that chemicals from injured fish elicit an alarm reaction, which is partially inhibited by feeding motivation.
INTRA- AND INTERINDIVIDUAL VARIATION IN THE CONTACT CALLS OF SPECTACLED PARROTLETS (FORPUS CONSPICILLATUS)
Authors: Wanker Ralf , Fischer Judith 
Published: July 2002

Abstract
The ability to discriminate individuals or different social classes of individuals is important for the evolution of social behaviour. In animal societies with ample social relationships selection will often favour the capacity to signal and perceive the identity and the membership to a certain social class. Spectacled parrotlets (Forpus conspicillatus, Psittacidae, Psittaciformes) live in a complex system of social relationships throughout their lives and are able to recognize their mates and their siblings on the basis of their contact calls. Here we attempt to identify the acoustic parameters that might be used in individual recognition and recognition of social categories. Therefore we analysed recordings of contact calls with reference to the variation of certain acoustical parameters. There was significant interindividual variation in the peak frequency, maximum frequency, duration, energy, bandwidth and minimum frequency in the contact calls of spectacled parrotlets. Discriminant function analysis has shown individual and social subunit specific calls but also that individuals of different social classes share some calls. From our results we hypothesize that spectacled parrotlets could use at least six acoustical cues in their contact calls that might encode information about the individual, the age class, the pair, the pairing status and the family.
BEHAVIORAL SYNCHRONY IN IBEX GROUPS: EFFECTS OF AGE, SEX AND HABITAT
Authors: Ruckstuhl Kathreen , Neuhaus Peter 
Published: July 2002

AbstractSynchrony of activities is usually high in foraging groups, possibly to maintain group cohesion. Individuals with different levels of activity budgets, however, may have a hard time synchronizing their behavior to each other without incurring a cost. We predicted that the age and sex structure of a group would affect synchronization levels within a group because of differing individual activity budgets. Individuals in same-sex-age groups were hypothesized to show higher levels of activity synchrony than individuals in mixed sex-age groups. We investigated activity synchrony in adult male, adult female, subadult, and mixed sex-age groups of Alpine ibex - one of the most sexually dimorphic ruminant species. Activity budgets and movement rates were measured to calculate synchrony of activities between group members in June and July 1999. Adult males were more synchronized with group peers than either females or subadults of both sexes. However, while adult males were synchronized in 81% when in bachelor (adult male) groups, they were only synchronized in 65% of the time when in mixed sex-age groups. Adult females were synchronized 61% of their time when in mixed sex-age groups and 69% when in female groups. Individual subadult males displayed higher synchrony when in bachelor or female groups than when in mixed sex-age or subadult mixed-sex groups. Subadult groups and mixed sex-age groups showed the lowest degree of synchrony of all group types. In general, animals in groups of same body-sized individuals were more synchronized with their group members than animals in mixed body-size groups. Two and three year-old males did not adjust their time spent lying to the group but their time spent walking. They also tended to change their time spent grazing and standing according to group type. Among subadults, females spent more time foraging than males but less time lying and standing. There was no difference in time spent walking. Bachelor and subadult groups had the greatest movement rates while female groups were relatively sedentary within escape terrain. Individuals in escape terrain did only marginally synchronize their behavior to each other likely because groups did not move much and synchrony was presumably less important. We conclude that habitat type, group movement rates, and a group's sex-age composition may affect the extent to which an individual will synchronize its activities to the other group members.
THE 'WHINNY' OF SPIDER MONKEYS: INDIVIDUAL RECOGNITION BEFORE SITUATIONAL MEANING
Authors: Teixidor Patricia , Byrne Richard 
Published: July 2002

Abstract
When spider monkeys (Ateles geoffroyi) are dispersed and moving through wooded areas in the dry forest of Santa Rosa National Park in Costa Rica, they give loud calls, whinnies, that can be heard over long distances and appear to be answered with the same call from other monkeys. We examined the circumstances in which this vocalization was emitted and the responses elicited from other group members. A total of 105 h of continuous recordings on emission of whinnies, 113 h of individual focal samples and 291 spectrograms were analyzed from a study group with 15 identified subjects. Whinnies emitted in different circumstances caused different reactions. Whinnies provoked by the sight of an observer were never responded to in any particular way, while those given during resting or feeding sometimes caused an active response of approach or calling. Most strikingly, whinnies given during group movement provoked hearers to approach or call significantly more often than either those given while feeding or resting. Playback experiments found one response, 'scan', to differ according to the original circumstances of emission of the broadcast call: monkeys scanned more in the direction of the sound when hearing feeding rather than group movement whinnies.
DOES THE BEHAVIOUR OF THE NEONATE INFLUENCE THE EXPRESSION OF MATERNAL BEHAVIOUR IN SHEEP?
Authors: Dwyer  , Lawrence  
Published: July 2002

Abstract
Maternal care is provided in response to cues from the offspring. The role of offspring stimuli in determining the quality of maternal care was assessed using the sheep (Ovis aries) as a model. The effects of variation in lamb behaviour on the expression of maternal behaviour in a hill (Scottish Blackface) and a lowland (Suffolk) breed of ewe was examined by embryo transfer of single embryos between the two breeds to give the four possible combinations of ewe and lamb. Labour was significantly shorter for both breeds of ewe when delivering Blackface lambs than Suffolk lambs. Blackface lambs were also significantly more active than the Suffolk lambs in the first 3 days after birth; there was no effect of maternal breed. Despite these differences in both length of labour and lamb activity at birth with lamb breed, the behaviours of the ewe associated with the onset of maternal care (e.g. licking the lamb, allowing the lamb to the udder, absence of aggressive behaviours) were unaffected by the breed of lamb. Suffolk ewes, however, were more likely to show an aversive reaction to their lamb, spent less time licking the lamb and were more likely to move as the lamb approached the udder. There was a significant influence of ewe breed on lamb sucking behaviour. Suffolk ewes received significantly more sucking attempts than Blackface ewes from both breeds of lamb. A higher sucking rate on Suffolk ewes continued over the first 3 days after birth. Other behaviours, such as playing, were specific to lamb breed and not affected by ewe behaviour at this time. These data suggest that offspring behaviour had no effect on the onset of bonding behaviours of the ewe. Neonatal lamb activity was also largely independent of the behaviour of their dam. However, sucking behaviour of the lamb was modified by ewe behaviour and this may affect the strength of the bond between ewe and lamb.
Influence of Chicks and Food Quality on Food Calling in Broody Domestic Hens
Authors: Wauters A.M. , Richard-Yris M.A. , Pierre J.S. , Lunel  , Richard J.P. 
Published: July 2002

Abstract
The aim of this study was to understand the relationship between production of food calls by maternal hens and both food quality and social context. Nineteen broody hens were tested in twenty experiments combining four different food contexts with five social situations in which they could receive different levels of stimuli from their chicks. Results revealed that the food call rates of broody hens were positively correlated with food quality (or motivational state with regard to food). They were also influenced by the caller's social context: presence of chicks, behaviour of chicks and separation from chicks modified food call production. These results are therefore consistent with previous reports on food calling by cockerels.
Evaluation of the energy barrier for dehydration of homoionic (Li, Na, Cs, Mg, Ca, Ba, Alx(OH)yz+ and La)-montmorillonite by a differentiation method
Authors: Zabat M. , Van Damme H. 
Published: July 2002

AbstractThe thermal energy necessary for the removal of molecular water from Li+-, Na+-, Cs+-, Mg2+-, Ca2+-, Ba2+-, Alx(OH)yz+- and La3+-homoionic montmorillonite powders was determined by thermogravimetric analysis under atmospheric pressure. The weight loss curves and their derivatives exhibit one or several features related to the various populations of water molecules. The activation energy for water removal, which is the sum of the adsorption energy and the activation energy for diffusion, was calculated in each case using a simple first-order differentiation method. The results allow the physisorbed water and the water coordinated to the cations to be clearly separated. For the later population and with the exception of the Na-clay, a good correlation was found between the temperatures and activation energies for water removal and the polarizing power of the cations. Comparison with the results of mechanical tests performed on similar samples suggests that the creep of smectite clays is not controlled by mobility of the individual water molecules but by the mobility of the interlayer cations surrounded by their hydration shell.