bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of typical contours in object processing by children
Authors: Derȩgowski J. B. , Parker D. M. , Dziurawiec S.
Published: July 2011

Draughtsmen depicting objects often do so by means of outlines derived in a systematic manner from the objects' surfaces. These outlines represent those points on a solid's surface where the surface appears to change rapidly; a line joining these points of maximum change is here termed a typical contour. Previous research (Dziurawiec & Deregowski, 1992) has shown that children's distorted drawings of animal models may be explained by the child's tendency to depict typical contours for different regions of an object, e.g. head, trunk, tail, and bring these together in a single drawing. The present paper extends this research to the role of typical contours in the discrimination and recognition of unfamiliar solids. In Expt 1 results collected from 108 nursery school children indicate that learning to discriminate between unfamiliar models is significantly improved when the models' typical contours are presented in the participants' fronto‐parallel plane. In Expt 2 data collected from a further 107 nursery school children established that when all views of an unfamiliar object are available, nursery school children readily abstract the typical contours and use them as an aid to subsequent recognition. The utility of the typical contours approach, previously demonstrated for object depiction, is confirmed for object recognition.
Hidden‐feature inclusions in children's drawings: The effects of age and model familiarity
Authors: Krascum Ruth , Tregenza Clair , Whitehead Paul
Published: July 2011

Two experiments examined factors affecting the frequency of hidden‐feature inclusions in children's drawings. In the first study, 4‐ to 6‐year‐olds and 7‐ to 9‐year‐olds were presented with a cup and a novel object to draw; in both cases the feature of primary functional importance was occluded. When the cup was named and examined prior to drawing only the younger children showed a high incidence of commission errors. When the novel object was named and examined and its function explained, by contrast, commission errors occurred very frequently in both age groups. In the second study, 4‐ to 5‐year‐olds and 8‐year‐olds were asked to draw two novel objects. As for Expt 1, naming and visual inspection accompanied by an explanation of function were found to provoke commission errors by both younger and older children. When the description of function was omitted, however, commission errors were almost entirely restricted to the younger participants. The present results demonstrate that model novelty may tempt children to include hidden features in their drawings beyond the age when commission errors are normally expected for familiar objects. One explanation of these findings is that the features included in children's drawings of a novel object represent those properties that are salient in the formation of a new concept.
Children's overestimation of the knowledge to be gained from seeing
Authors: Robinson E. J. , Thomas G. V. , Parton A. , Nye R.
Published: July 2011

In three investigations children aged 4–9 years were given a sequence of trials on each of which they experienced pairs of objects which looked the same but felt different (such as full and empty cereal packets) or felt the same and looked different (such as chocolate bars with different coloured wrappers). On each trial the experimenter chose one of the items from a pair and children predicted whether they themselves, or another person or doll, would know which one it was just by seeing it. In two of the three investigations, even the youngest children showed clear evidence of discriminating in their knowledge judgments between the two types of pairs, but nevertheless children frequently overestimated the knowledge to be gained from seeing. Errors of overestimation when the visual input was ambiguous as to feel were correlated with those made when the visual input was ambiguous as to size, suggesting the children's problem was not specific to understanding about the modality‐specific aspect of knowledge. Furthermore, making it easier for children to isolate the visual input from an object from the non‐visual was ineffective in reducing errors of overestimation. These results provide no evidence that children had difficulty imagining or isolating the visual aspect of the chosen object, but suggest that they may fail to realize when the input is ambiguous.
Security and symbolic play: The relation between security of attachment and executive capacity
Authors: Meins Elizabeth , Russell James
Published: July 2011

The study reported here investigated the relationship between security of attachment and children's solo and instructed symbolic play. Participants were 43 (27 secure and 16 insecure) 21/2‐year‐olds, whose security of attachment had been assessed in infancy. No differences were found in the sophistication of solo symbolic play between the secure and insecure groups, but the securely attached children were better able to incorporate an experimenter's suggestions into their sequences of pretence. In addition, the securely attached children were found to have greater ‘executive capacity’ scores (Belsky, Garduque & Hrncir, 1984). These data show that securely attached children are better able to benefit from the play suggestions of an unfamiliar adult, and thus extend the findings of Slade (1987) on maternal enhancement of children's play. The relationship between security of attachment and response to suggestions for symbolic play is discussed within a Vygotskian framework, and the possibility that these results are evidence for the greater social responsiveness and flexibility of securely attached children is addressed.
Eye‐direction detection: A dissociation between geometric and joint attention skills in autism
Authors: Leekam Susan , Baron‐Cohen Simon , Perrett Dave , Milders Maarten , Brown Sarah
Published: July 2011

This study examined differences between children with autism and control children in the ability to follow another person's direction of gaze. In Expt 1, children with autism, Down syndrome and normally developing children were given two tasks. The gaze monitoring task (GMT) measured the child's spontaneous tendency to follow gaze direction in response to another person's change of head and eye movement. The visual perspective taking task (VPT) measured the child's ability to compute and report what the other person was looking at, when instructed to do so. Results showed that the majority of Down syndrome and normal children passed both tasks. In contrast, children with autism failed the GMT. This failure could not have been due to a lack of the relevant geometric skill, as they passed the VPT. This geometric skill was examined further in Expt 2, using a fine discrimination task which tested children's ability to discriminate degrees of change in the orientation of gaze. Children with autism were well within their developmental age level on this task. These results indicate a dissociation between (impaired) spontaneous monitoring and (intact) geometric analysis of gaze‐direction.
Three‐year follow‐up of normal fear in children and adolescents aged 7 to 18 years
Authors: Gullone Eleonora , King Neville J.
Published: July 2011

Normative fears of 273 children and adolescents aged between 7 and 18 years were examined over a three‐year period. Respondents' gender and initial fear scores were found to be better predictors of follow‐up fear scores than age suggesting a trait component to fearfulness and underlining the pervasive influence of gender on fearfulness. Also, the results yielded a general decrease in fearfulness between initial and follow‐up assessment which was most marked for the 7‐ to 10‐year‐olds. At approximately 11 years of age a degree of stability for all fears, with the exception of psychic stress‐related fears, became apparent. In contrast, for these fears there was a general increase over time. Older children and boys reported fewer fears and a lower intensity of fearfulness than younger children and girls, respectively. The most common fears related to death and danger and were relatively stable over time.
Security of attachment and maternal tutoring strategies: Interaction within the zone of proximal development
Authors: Meins Elizabeth
Published: July 2011

The study investigated the relationship between children's security of attachment and mothers' ability to tutor their children within the ‘region of sensitivity to instruction’ (Wood & Middleton, 1975). Thirty‐seven mothers and their 3‐year‐olds who had been classified as securely or insecurely attached in infancy participated on a box construction task. Compared with mothers in the insecure group, mothers of securely attached children used proportionately more positive feedback, less negative feedback and tended to use physical intervention only if the child requested their help. Mothers whose children were securely attached were also more likely to use feedback from their children's performance in gauging the level of specificity of their succeeding instructions. Although the differences in the use of positive and negative feedback between the secure and insecure group mothers may be explained in terms of socio‐economic status (SES), there were no SES‐based differences on the measures of physical intervention or sensitivity to feedback. The results are discussed with reference to the securely attached child's posited greater autonomy, and the possibility that mothers of securely attached children are better able to recognize their child's level of competence resulting in them pitching their interventions at an appropriate level.
Gender biases in children's memory for expected and unexpected objects in real‐world settings
Authors: Carelli Maria Grazia , Mäntylä Timo
Published: July 2011

Children's memory for unexpected and expected objects in real‐world settings were examined in three experiments. The setting of Expt 1 reflected male interests (a doctor's examination room), whereas the setting of Expt 2 was more compatible with female interests (a beauty salon). In both studies, 6‐ and 9‐year old boys and girls viewed objects that were consistent or inconsistent with expectations about each environment. The results of the experiments showed a consistency effect in that recognition memory for unexpected was better than that for expected objects for both age groups. However, the magnitude of the consistency effect interacted with age and gender, so that older boys, but not older girls, showed an absence of the consistency effect in the doctor's setting (Expt 1), whereas older girls showed a similar pattern in the beauty‐salon setting (Expt 2). Experiment 3 provided independent evidence for the assumption that the two settings induced gender‐related biases. The findings of the study indicate that the effects of expectancies on school‐age children's episodic remembering are sensitive to gender‐related biases, and that these schematic effects may be more complex and dynamic than proposed by the general schema‐theoretic formulations of the consistency effect.
Children's attributions of moral emotions to victimizers: Some data, doubts and suggestions
Authors: Lourenço Orlando
Published: July 2011

The main goal of this research was to re‐examine contradictions between several published studies of age‐related changes in children's attributions of moral emotions to transgressors, and to analyse the robustness of young children's tendency to fall into the happy victimizer pattern (is. to expect a wrongdoer to feel good rather than bad after having committed n certain moral transgression). Ninety children of three age levels (ie. 4‐, 6‐ and 8‐year‐olds) were first confronted with two stories involving a wrongdoer, and then judged how the story's character felt. Next, the children were presented with additional opportunities designed to lessen the incidence of young children's attributions of positive (is. immoral) emotions to the victimizer. Although a developmental trend from positive to negative emotions was evident, children at all ages were more likely to attribute positive rather than negative emotions to the victimizer. However, older children changed their initial attributions of positive feelings into negative emotions more often than did younger children. These results are discussed in comparison with the findings of related studies, and also in relation to theoretical accounts of young children's morality.
Emotions, conflicts and aggression during preschoolers' freeplay
Authors: Arsenio William F. , Lover Anthony
Published: July 2011

This study addressed the connections among preschoolers' emotion displays and their aggressive and non‐aggressive peer disputes. Observers recorded 37 4 &1/2; to 5&1/2;‐year‐olds' discrete emotion displays and emotional intensity, and several aspects of their dispute‐related behaviour during freeplay using standardized checklists. Overall, children's baseline emotions (i.e. outside of disputes) and their emotions during disputes were somewhat interrelated, and these emotion displays were associated with children's participation in disputes with their peers, and to a lesser degree their continued post‐dispute interactions. Emotion intensity was also related to rates of peer disputes. These findings were qualified, however, by the type of dispute (aggressive vs. non‐aggressive conflicts) and the context of participants' emotions (baseline vs. dispute‐related emotions). Overall, emotions were most clearly linked with children's initiation of aggression, and a combination of percentage baseline anger, aggression‐related anger, and aggression‐related happiness predicted nearly a quarter of the variance in children's initiation of aggression.
Models and rulers in dynamical development
Authors: Rose Samuel P. , Fischer Kurt W.
Published: July 2011

Non‐linear dynamics holds enormous promise for transforming the field of development, moving it from rich but loose descriptions of developmental processes toward powerfully explicated dynamical models of change that are closely linked to empirical data about growth functions. The study of cusp catastrophes in developmental transitions provides an example of the beginning of this transformation. For the dynamics revolution to live up to its promise, researchers need not only to build on the tools that are explained in this special issue but also to move beyond catastrophe models of transition to deal with a fuller range of developmental processes, including hierarchical‐growth and predator‐prey models. If researchers are to ground these models effectively in observations, they must focus on building sound rulers of development to replace the poorly constructed scales that are the norm in the study of cognitive development. The papers in this special issue point the way towards achieving important parts of this agenda.
Young children's understanding of the non‐physical nature of thoughts and the physical nature of the brain
Authors: Watson Julanne K. , Gelman Susan A. , Wellman Henry M.
Published: July 2011

Two studies addressed pre‐schoolers' understanding of the non‐physical nature of thinking, as well as their understanding of the physical nature of the brain. Specifically, we considered whether young children understand that entities such as thought‐about items are mental, not physical, versus the possibility that they think mental entities are physical but simply inaccessible. In addition, we considered the possibility that children may conceive of the brain, a physiological but mentally involved organ, as not physical, instead of the adult‐like belief that the brain is physical. Mental entities were compared to real physical and inaccessible entities, namely swallowed items, and the brain was compared to the stomach. Study 1 showed that although correct responses increased with age, 3‐year‐olds, as well as 4‐ and 5‐year‐olds, clearly understood that the thought‐about objects were not physically in the head, whereas swallowed objects were physically inside the body. Study 2 extended and replicated these results in another sample of 3‐year‐olds, using more stringent methods. Three‐year‐olds in both studies performed at chance in judging the brain as a physically present object, but both 4‐ and 5‐year‐olds understood that the brain, like the stomach, is a physical object inside the body.
Context dependency in parental speech
Authors: Reissland Nadja
Published: July 2011

Twelve children, six girls and six boys, were videotaped at two ages: first at a mean age of 11:16 months, second at a mean age of 15:16 months, with a parent in their home while having a meal with a spoon (non‐play situation) and feeding a doll with a spoon (play situation). It was found that parents reliably differentiated between play and non‐play situations by using interaction and instruction frames, respectively. A discriminant function analysis of the relative frequency of seven speech acts used within each frame resulted in the correct classification of 60.42 per cent of the children. These findings are discussed in the light of theories of children's learning in context (Snow, Perlmann & Nathan, 1987), specifically their learning about pretend and real situations (Harris & Kavanaugh, 1993).
Poor readers' ability to detect speech rhythm and perceive rapid speech
Authors: Wood Clare , Terrell Colin
Published: July 2011

Recent research indicates that the rhythmic properties of speech may indicate to the infant listener where word boundaries are most likely to occur. However, rhythmic awareness is not included in present discussions of phonological awareness. It is suggested that skills which develop in early infancy to facilitate speech perception (i.e. awareness of rhythm) may have an impact upon later phonological development and literacy. This paper outlines a cross‐sectional study, designed to examine whether poor readers do show a specific insensitivity to rhythm in speech, and whether they also exhibit signs of inefficient speech perception. Thirty primary school children identified as poor readers were matched for age and gender, and for reading age and gender with two groups of children reading at a level comparable with their chronological age (“normal” readers) (N = 90). All children completed a battery of tasks, including an assessment of rapid speech perception, rhythmic awareness, rhyme detection and phoneme deletion. The results suggest that poor readers do experience a developmental delay on rhythmic awareness, although there is no significant difference in the children's ability to perceive speech once vocabulary is taken into account. Suggestions are made regarding the need to consider non‐segmental skills in definitions of phonological awareness, and how this may contribute to our understanding of phonological development.
Distinguishing between memories for thoughts and deeds: The role of prospective processing in children's source monitoring
Authors: Foley Mary Ann , Ratner Hilary Horn
Published: July 2011

The source monitoring abilities of children and adults were compared by asking both age groups to distinguish between memories for performed and imagined actions. The identity of the person performing actions (self vs. other), as well as the identity of the person imagined (self vs. other) were varied to create four kinds of performhagine conditions. Results showed that 6‐year‐olds performed worse than adults in all four conditions, and they were more likely than adults to claim an imagined action was actually performed (Expt 1). This bias to claim an imagined action was performed was more pronounced for children who imagined themselves going through the motions of performing actions compared to those who imagined seeing themselves (Expt 2). Action similarity played a role in source monitoring, but only under some conditions. The results point to the importance of prospective processing for children's source monitoring, and suggest that systematic investigation of the goal‐directed nature of actions in source monitoring is needed.
Infant gaze following based on eye direction
Authors: Moore Chris , Corkum Valerie
Published: July 2011

This experiment investigates the role of eye direction in infant joint visual attention. Sixty‐three infants aged from 8 to 19 months participated in a training study in which they were shown adult eye turns in association with the appearance of an interesting sight to one or the other side. It was only at 18–19 months of age that infants showed a reliable ability to use the adult eye turns to predict the side of appearance of the target. this finding suggests that before 18 months of age, infants do not recognize the significance of eye direction for joint visual attention.
Self‐monitoring in poor and good reading comprehenders and their use of strategy
Authors: Cataldo M. Giulia , Cornoldi Cesare
Published: July 2011

The present research examines the ability of 6th‐ and 7th‐grade poor and good comprehenders to monitor their comprehension during reading and also examines their consequent activation of strategies. In particular, we considered the process of search through the text, that is moving up and down the text in order to find relevant information to respond to subsequent questions. In order to study this process, good and poor comprehenders were invited to read a descriptive passage and to respond to questions, some of which were embedded in the text and some of which were at the end of the text. Half of the participants in each group were also required to give a confidence rating of their response accuracy. Both groups benefited from the embedded questions, thus revealing that a specific search process affects the difficulty in responding to questions. Further, poor comprehenders were able to monitor their accuracy (i.e. know how well they understand). Finally the monitoring requirement did not have a positive influence on comprehension.

A second experiment tested whether the poorer performance of poor comprehenders for the questions at the end of the text was due to an inability to search through the text in order to find the required information or to a deficit in strategy utilization. When explicitly invited to search through the text, poor comprehenders were able to search and improve their performance, suggesting that their failure with the final questions in Expt 1 was at least partially due to a deficit in strategy utilization.
Handedness, footedness, eyedness and earedness in the Colorado Adoption Project
Authors: Saudino K. , McManus I. C.
Published: July 2011

Dominance of hand, foot, ear and eye was examined in the Colorado Adoption Project (CAP) to examine whether previously reported familial trends in lateralization are the result of genetic or environmental processes. Despite a relatively large sample size for an adoption study, and evidence that the measures of lateralization were typical of those found in other studies, no significant familial trends were found in any of the measures of direction of lateralization. Nevertheless, effects found for handedness were of a similar magnitude to that shown elsewhere in the literature and it was concluded that this adoption study alone did not have sufficient statistical power to partition variance into genetic and environmental components. Other studies taken alone are also likely to suffer from the same problem, and therefore the question is only likely to be definitively resolved by combining data from a number of studies by means of meta‐analysis.

Degree of lateralization was also examined and no evidence was found for familial trends in handedness, footedness, eyedness or earedness. Power analysis suggested that the present data were sufficient to detect effects similar to those previously reported for handedness and that this result was best interpreted as a true failure of replication of familial association for handedness. The study is also the first to examine degree of eyedness, earedness and footedness, and finds no evidence for familial associations.
Congenital visual impairment and ‘theory of mind’
Authors: Minter Maggie , Hobson R. Peter , Bishop Martin
Published: July 2011

On theoretical grounds, Hobson (1990) suggested that lack of vision might delay the emergence of so‐called ‘theory of mind’ in congenitally blind children. This prediction was tested using tactile versions of theory of mind tasks devised by Perner, Leekam & Wimmer (1987) and Wimmer & Perner (1983). Twenty‐one visually impaired children were group matched for chronological age and verbal intelligence with 21 sighted children. All of the children who participated in the study had mental ages over the age of 4 years. Visually impaired children's performance on the two theory of mind tasks was significantly poorer than that of their sighted peers, but most of the children could make some adjustment to another person's false beliefs. The possible sources and implications of these findings are discussed with reference to accounts of ‘theory of mind’ development.
The role of similarity in developmental differences in source monitoring
Authors: Day Kylie , Howie Pauline , Markham Roslyn
Published: July 2011

Previous developmental studies of source monitoring have suggested that young children's discriminative difficulties are confined to certain tasks. Various explanations for these findings have been offered. The present study examined three factors that may account for some developmental differences in source monitoring performance: action similarity, person similarity, and involvement of the self. Six‐ and 12‐year‐old children carried out source monitoring tasks in which performed and imagined actions were either similar or dissimilar, and the agents of performed and imagined actions were either different or the same. Within the same actor condition, the agent was (i) always the self, or (ii) always another person. Strong effects of age and action similarity were found, but the results failed to support unequivocally the unique importance for developmental trends of any one of the three factors we investigated. The results suggest that multiple factors may contribute to age differences in source monitoring, either individually or in combination, including various dimensions of similarity, as well as the role of the self.
Executive function in preschoolers: Links with theory of mind and verbal ability
Authors: Hughes Claire
Published: July 2011

Fifty preschool children (mean age 3:11 years) took part in an investigation of the relations between children's executive function performance, their understanding of mind and their language skills. The study demonstrates the feasibility of testing rudimentary executive function skills among preschoolers, using an original battery of tasks. The results were consistent with those from studies of older children (e.g. Welsh, Pennington & Groisser, 1991), in that three aspects of executive function were distinguished: working memory, attentional flexibility and inhibitory control. In addition, specific links were found between executive function and theory‐of‐mind performance, even when age and both verbal and non‐verbal ability were taken into account. In particular, children's deceptive abilities were closely related to success on tests of inhibitory control. The implications of these results for our understanding of deceit are discussed.
Presynaptic Ca2+ influx and vesicle exocytosis at the mouse endbulb of Held: a comparison of two auditory nerve terminals
Authors: Lin Kun‐Han , Oleskevich Sharon , Taschenberger Holger
Published: July 2011

Non‐technical summary  The release of neurotransmitter from presynaptic nerve endings is triggered by Ca2+ influx through voltage‐gated Ca2+ channels (VGCCs) that open when an action potential (AP) invades the presynaptic terminal. The functional properties of VGCCs expressed in presynaptic terminals remain elusive because most terminals are too small to be accessible to electrophysiological recordings. We performed direct presynaptic recordings to characterize Ca2+ channels and transmitter release in a large mammalian presynaptic terminal, the endbulb of Held. Endbulb terminals are formed by the endings of auditory nerve fibres that contact bushy cells located in the anterior ventral cochlear nucleus. We find that endbulb terminals are endowed with >1000 readily releasable vesicles and express an average number of >6000 VGCCs. About half of the VGCCs open during a single AP. Thus, multiple Ca2+ channels control the release of a single transmitter vesicle at the endbulb of Held.
Neurovascular protection by ischaemic tolerance: role of nitric oxide
Authors: Iadecola Costantino , Kahles Timo , Gallo Eduardo F. , Anrather Josef
Published: July 2011

Abstract  Nitric oxide (NO) has emerged as a key mediator in the mechanisms of ischaemic tolerance induced by a wide variety of preconditioning stimuli. NO is involved in the brain protection that develops either early (minutes–hours) or late (days–weeks) after the preconditioning stimulus. However, the sources of NO and the mechanisms underlying the protective effects differ substantially. While in early preconditioning NO is produced by the endothelial and neuronal isoform of NO synthase, in delayed preconditioning NO is synthesized by the inducible or ‘immunological’ isoform of NO synthase. Furthermore, in early preconditioning, NO acts through the canonical cGMP pathway, possibly through protein kinase G and opening of mitochondrial KATP channels. In late preconditioning, the protection is mediated by peroxynitrite formed by the reaction of NO with superoxide derived from the enzyme NADPH oxidase. The mechanisms by which peroxynitrite exerts its protective effect may include improvement of post‐ischaemic cerebrovascular function, leading to enhancement of blood flow to the ischaemic territory, and expression of prosurvival genes resulting in cytoprotection. The evidence suggests that NO can engage highly effective and multifunctional prosurvival pathways, which could be exploited for the prevention and treatment of cerebrovascular pathologies.
SIRT‐1 and vascular endothelial dysfunction with ageing in mice and humans
Authors: Donato Anthony J. , Magerko Katherine A. , Lawson Brooke R. , Durrant Jessica R. , Lesniewski Lisa A. , Seals Douglas R.
Published: July 2011

Non‐technical summary  Advancing age is a major risk factor for the development of cardiovascular disease. A key characteristic of older arteries that may lead to cardiovascular disease is reduced endothelial function, characterized by blunted endothelium‐dependent dilatation. Sirtuins, specifically sirtuin‐1, are proteins linked to increases in lifespan and lower incidence of age‐related diseases. We hypothesized that diminished sirtuin‐1 with advancing age may alter regulation of a key endothelium dilatory enzyme, nitric oxide synthase. Our findings provide novel translational evidence that sirtuin‐1 expression and activity contribute to arterial endothelial dysfunction with ageing and that this may be due to altered nitric oxide synthase activation. Importantly, our results provide further compelling support for sirtuin‐1 as a potential therapeutic target for lifestyle and pharmacological interventions aimed at the prevention and treatment of arterial ageing and age‐associated cardiovascular diseases.
The influence of carbohydrate–protein co‐ingestion following endurance exercise on myofibrillar and mitochondrial protein synthesis
Authors: Breen Leigh , Philp Andrew , Witard Oliver C. , Jackman Sarah R. , Selby Anna , Smith Ken , Baar Keith , Tipton Kevin D.
Published: July 2011

Non‐technical summary  A single bout of exercise stimulates the production of new muscle proteins. Furthermore, ingesting protein in close proximity to exercise enhances the metabolic response. Long‐term exercise training promotes muscle adaptation, and the mode of exercise performed determines the type of proteins that are made. To date, the types of proteins that are made when protein is ingested after endurance exercise are not known. We report that when well‐trained male cyclists ingest protein with a carbohydrate drink after a high‐intensity ride, production of proteins responsible for muscle contraction is increased. Proteins responsible for aerobic energy production are not responsive to protein feeding. Furthermore, specific signals within the muscle that control protein synthesis are responsive to protein ingestion, providing a potential mechanism to underpin our primary findings. These results suggest that protein feeding after intense endurance exercise may be important in maintaining the structural quality and power generating capacity of the muscle.
Relationship Between Oxide-Ion Conductivity and Ordering of Oxygen Vacancy in the Ln2Zr2O7 (Ln = La, Nd, Eu) System Using High Temperature XRD
Authors: Hagiwara Takeshi , Yamamura Hiroshi , Nishino Hanako
Published: July 2011

The pyrochlore-type Ln2Zr2O7 (Ln = La, Nd, Eu) systems were refined by Rietveld analyses of XRD data combined with the MEM-based pattern fitting at RT, 873, 1073, and 1273 K. All the samples kept a single cubic phase of the pyrochlore-type structure in the temperature range up to 1273 K. The oxide-ion conductivities of the present systems were discussed on a basis of ordering of oxygen vacancy in the pyrochlore-type structure. Theoxide-ion conduction of Eu2Zr2O7 was ascribed to diffusion of oxygen along the 〈100〉 direction, while the hole conduction of La2Zr2O7 occurred along the 〈110〉 direction, according to the charge density map estimated by the MEM analysis.
Tribological Behavior of Heat Treated Ni-rich NiTi Alloys
Authors: Aliasgarian R. , Ghasemi H. M. , Abedini M.
Published: July 2011

Effects of heat treatments and applied loads on the tribological behavior of Ti-56.5 wt. % Ni and Ti-57.5 wt. % Ni alloys were investigated. Wear tests were performed on a pin-on-disk tribometer under normal loads of 20 N and 60 N at a sliding speed of 0.3 m/s. The results indicated that the alloys aged at 700 °C showed lower hardness comparing to the alloys aged at 400 °C. Under an applied load of 20 N, the samples aged at 700 °C showed better wear behavior in comparison with the samples aged at 400 °C with a higher hardness. This could be attributed to higher toughness of the samples aged at 700 °C. The results also showed that the wear of the samples aged at 400 °C decreased with the increase in normal load. However, there was an increase in the wear of the samples aged at 700 °C with the increase of load. Formation and stability of tribological layers on the contacting surfaces could be the main reason for the reduction of the wear of the samples aged at 400 °C with the increase in normal load.
Aeration in Lubrication With Application to Drag Torque Reduction
Authors: Aphale Chinar R. , Schultz William W. , Ceccio Steven L.
Published: July 2011

The aeration of an oil film flowing between the faces of two closely spaced circular plates (one stationary, and one rotating) is examined experimentally, numerically, and with an improved lubrication model. The gap between the plates is small compared to their radii, making lubrication theory appropriate for modeling the flow. However, standard lubrication boundary conditions suggested by Reynolds (1886, "On the Theory of Lubrication and its Application to Mr. Beauchamp Tower’s Experiments, Including an Experimental Determination of the Viscosity of Olive Oil," Philos. Trans. R. Soc. London, 177, pp. 157-234) of p = 0 and pn = 0 (Dirichlet and Neumann conditions on pressure) at the gas-liquid interface do not allow for the inclusion of a contact line model, a phenomenon that is important in the inception of aeration. Hence, the standard theory does not adequately predict the experimentally observed onset of aeration. In the present work, we modify the Neumann boundary condition to include both interfacial tension effects and the dynamics of the interface contact angle. The resulting one-dimensional Cartesian two-phase model is formulated to incorporate the prescribed contact line condition and tracks the interface shape and its motion. This model is then implemented in an axisymmetric, two-dimensional model of the rotating disk flow and used to predict the onset of aeration for varying surface tension and static contact angles. The results of the modified lubrication model are compared with experimental observations and with a numerical computation of the aerating flow using a volume of fluid method.
Separating Obesity from Hypertension
Authors: Foley John F.
Published: July 2011

NF-κB signaling in distinct neurons in the hypothalamus forms the link between obesity and hypertension.
Linking Endocytosis and Tumorigenicity
Authors: Thompson Heather M.
Published: July 2011

Activation of receptor tyrosine kinases may not be enough for oncogenesis; excess signaling from endosomes may also be required.
Targeting Glioma Stem Cells
Authors: Gough Nancy R.
Published: July 2011

Nitric oxide synthase-2 is a proliferation-promoting marker of glioma stem cells.
Regulating ROS for Tumorigenicity
Authors: Adler Elizabeth M.
Published: July 2011

Oncogenes can activate a reactive oxygen species-detoxification program to promote tumorigenesis.
PTEN Under Arrest
Authors: Wong Wei
Published: July 2011

The lipid phosphatase-dependent and independent functions of PTEN are activated and inhibited, respectively, by the adaptor protein β-arrestin.
Candida albicans Adhesion to and Invasion and Damage of Vaginal Epithelial Cells: Stage-Specific Inhibition by Clotrimazole and Bifonazole
Authors: Wächtler Betty , Wilson Duncan , Hube Bernhard
Published: July 2011

Clotrimazole and bifonazole are highly effective antifungal agents against mucosal
Candida albicans
infections. Here we examined the effects of low levels of clotrimazole and bifonazole on the ability of
C. albicans
to adhere, invade, and damage vaginal epithelial cells. Although adhesion and invasion were not affected, damage was greatly reduced upon azole treatment. This clearly indicates that low levels of azoles influence specific activities of
C. albicans
during distinct stages of vaginal epithelium infections.
Analysis of the Resistome of a Multidrug-Resistant NDM-1-Producing Escherichia coli Strain by High-Throughput Genome Sequencing
Authors: Poirel Laurent , Bonnin Rémy A. , Nordmann Patrice
Published: July 2011

The resistome of the multidrug-resistant
Escherichia coli
strain 271 carrying the plasmid-mediated
bla
NDM-1
carbapenemase gene was analyzed by high-throughput genome sequencing. The p271A plasmid carrying the
bla
NDM-1
gene was 35.9 kb in size and possessed an IncN-type backbone that harbored a novel replicase gene. Acquisition of the
bla
NDM-1
gene on plasmid p271A had been likely the result of a cointegration event involving the transposase of Tn
5403
. The expression of
bla
NDM-1
was associated with the insertion sequence IS
Aba125
likely originating from
Acinetobacter baumannii. E. coli
271 accumulated multiple resistance determinants, including five β-lactamase genes (comprising the extended-spectrum β-lactamase CTX-M-15), two 16S RNA methylase ArmA- and RmtB-encoding genes, and the
qepA
gene encoding an efflux pump involved in resistance to fluoroquinolones. These resistance genes were located on three additional plasmids, of 160 kb (IncA/C), 130 kb (IncF), and 110 kb (IncI1). In addition, several chromosomally encoded resistance determinants were identified, such as topoisomerase mutations, porin modifications and truncations, and the intrinsic
ampC
gene of
E. coli
that was weakly expressed. The multidrug resistance pattern observed for
E. coli
271 was therefore the result of combined chromosome- and plasmid-encoded mechanisms.
In Vitro
Activity against Staphylococcus aureus of a Novel Antimicrobial Agent, PRF-119, a Recombinant Chimeric Bacteriophage Endolysin
Authors: Idelevich Evgeny A. , von Eiff Christof , Friedrich Alexander W. , Iannelli Domenico , Xia Guoqing , Peters Georg , Peschel Andreas , Wanninger Ingrid , Becker Karsten
Published: July 2011

Antistaphylococcal activity of the novel chimeric endolysin PRF-119 was evaluated with the microdilution method. The MIC
50
and MIC
90
of 398 methicillin-susceptible
Staphylococcus aureus
isolates were 0.098 μg/ml and 0.391 μg/ml, respectively (range, 0.024 to 0.780 μg/ml). Both the MIC
50
and MIC
90
values of 776 methicillin-resistant
S. aureus
isolates were 0.391 μg/ml (range, 0.024 to 1.563 μg/ml). All 192 clinical isolates of coagulase-negative staphylococci exhibited MIC values of >50 μg/ml. In conclusion, PRF-119 exhibited very good activity specifically against
S. aureus
.
Sertaconazole Nitrate Shows Fungicidal and Fungistatic Activities against Trichophyton rubrum, Trichophyton mentagrophytes, and Epidermophyton floccosum, Causative Agents of Tinea Pedis
Authors: Carrillo-Muñoz Alfonso J. , Tur-Tur Cristina , Cárdenes Delia C. , Estivill Dolors , Giusiano Gustavo
Published: July 2011

The fungistatic and fungicidal activities of sertaconazole against dermatophytes were evaluated by testing 150 clinical isolates of causative agents of tinea pedis,
Trichophyton rubrum
,
Trichophyton mentagrophytes
, and
Epidermophyton floccosum
. The overall geometric means for fungistatic and fungicidal activities of sertaconazole against these isolates were 0.26 and 2.26 μg/ml, respectively, although values were higher for
T. mentagrophytes
than for the others. This is the first comprehensive demonstration of the fungicidal activity of sertaconazole against dermatophytes.
Spread of IS
CR1
Elements Containing
bla
DHA-1
and Multiple Antimicrobial Resistance Genes Leading to Increase of Flomoxef Resistance in Extended-Spectrum-β-Lactamase-Producing Klebsiella pneumoniae
Authors: Lee Chen-Hsiang , Liu Jien-Wei , Li Chia-Chin , Chien Chun-Chih , Tang Ya-Fen , Su Lin-Hui
Published: July 2011

Increasing resistance to quinolones, aminoglycosides, and/or cephamycins in extended-spectrum-β-lactamase (ESBL)-producing
Enterobacteriaceae
exacerbates the already limited antibiotic treatment options for infections due to these microbes. In this study, the presence of resistance determinants for these antimicrobial agents was examined by PCR among ESBL-producing
Klebsiella pneumoniae
(ESBL-KP) isolates that caused bacteremia. Pulsed-field gel electrophoresis was used to differentiate the clonal relationship among the isolates studied. Transferability and the location of the resistance genes were analyzed by conjugation experiments, followed by DNA-DNA hybridization. Among the 94 ESBL-KP isolates studied, 20 isolates of flomoxef-resistant ESBL-KP were identified. They all carried a DHA-1 gene and were genetically diverse. CTX-M genes were found in 18 of the isolates. Among these DHA-1/CTX-M-producing
K. pneumoniae
isolates, IS
CR1
was detected in 13 (72%) isolates,
qnr
genes (1
qnrA
and 17
qnrB
genes) were detected in 18 (100%),
aac(6
′
)-Ib-cr
was detected in 11 (61%), and 16S rRNA methylase (all
armA
genes) was detected in 14 (78%). Four transconjugants were available for further analysis, and
qnrB4
,
aac(6
′
)-Ib-cr
,
armA
, and
bla
DHA-1
were all identified on these self-transferable
bla
CTX-M
-carrying plasmids. The genetic environments of IS
CR1
associated with
armA
,
bla
DHA-1
, and
qnrB4
genes in the four transconjugants were identical. Replicon-type analysis revealed a FIIA plasmid among the four self-transferable plasmids, although the other three were nontypeable. The cotransfer of multiple resistance genes with the IS
CR1
element-carrying plasmids has a clinical impact and warrants close monitoring and further study.
Mutation of RNA Polymerase β Subunit (
rpoB
) Promotes hVISA-to-VISA Phenotypic Conversion of Strain Mu3
Authors: Matsuo Miki , Hishinuma Tomomi , Katayama Yuki , Cui Longzhu , Kapi Maria , Hiramatsu Keiichi
Published: July 2011

The clinical vancomycin-intermediate
Staphylococcus aureus
(VISA) strain Mu50 carries two mutations in the
vraSR
and
graRS
two-component regulatory systems (TCRSs), namely,
vraS(I5N
) and
graR(N197S
) (hereinafter designated
graR
*). The clinical heterogeneously vancomycin-intermediate
S. aureus
(hVISA) strain Mu3 shares with Mu50 the mutation in
vraS
that encodes the VraS two-component histidine kinase. Previously, we showed that introduction of the plasmid p
graR
*, carrying the mutated two-component response regulator
graR
*, converted the hVISA strain Mu3 into VISA (vancomycin MIC = 4 mg/liter). Subsequently, however, we found that the introduction of a single copy of
graR
* into the Mu3 chromosome by a gene replacement method did not confer on Mu3 the VISA phenotype. The gene-replaced strain Mu3
graR
* thus obtained remained hVISA (MIC ≤ 2 mg/liter), although a small increase in vancomycin MIC was observed compared to that of the parent strain Mu3. Reevaluation of the Mu3 and Mu50 genomes revealed the presence of another mutation responsible for the expression of the VISA phenotype in Mu50. Here, we demonstrate that in addition to the two regulator mutations, a third mutation found in the Mu50
rpoB
gene, encoding the RNA polymerase β subunit, was required for Mu3 to achieve the level of vancomycin resistance of Mu50. The selection of strain Mu3
graR
* with rifampin gave rise to
rpoB
mutants with various levels of increased vancomycin resistance. Furthermore, 3 (33%) of 10 independently isolated VISA strains established from the heterogeneous subpopulations of Mu3
graR
* were found to possess
rpoB
mutations with or without an accompanying rifampin-resistance phenotype. The data indicate that a sizable proportion of the resistant hVISA cell subpopulations is composed of spontaneous
rpoB
mutants with various degrees of increased vancomycin resistance.
Determination of Posaconazole Levels in Toenails of Adults with Onychomycosis following Oral Treatment with Four Regimens of Posaconazole for 12 or 24 Weeks
Authors: Krishna Gopal , Ma Lei , Martinho Monika , Prasad Pratapa , Wahl Janice , Tavakkol Amir
Published: July 2011

Pharmacokinetic data from a randomized, parallel-group, multicenter study are presented. Adults with toenail onychomycosis (
n
= 146) received posaconazole (100 mg, 200 mg, or 400 mg) once daily (QD) for 24 weeks or 400 mg QD for 12 weeks. The posaconazole concentration in the great toenail exhibited a dose-related increase starting at week 2 for 24 weeks and a mean toenail-to-plasma concentration ratio of approximately 3:1 at the end of treatment for the 400-mg 24-week dose.
Emergence of Ertapenem Resistance in an Escherichia coli Clinical Isolate Producing Extended-Spectrum β-Lactamase AmpC
Authors: Guillon Hélène , Tande Didier , Mammeri Hedi
Published: July 2011

Escherichia coli
isolate MEV, responsible for a bloodstream infection, was resistant to penicillins, cephalosporins, and ertapenem. Molecular and biochemical characterization revealed the production of a novel, chromosome-borne, extended-spectrum AmpC (ESAC) β-lactamase with a Ser-282 duplication and increased carbapenemase activity. This study demonstrates for the first time that chromosome-borne ESAC β-lactamases can contribute to the emergence of ertapenem resistance in
E. coli
clinical isolates.