bluuebunny/crossref_metadata_2025 huggingface dataset:
Motives for lifestyle and exercise activities: A comparison using the theory of planned behaviour
Authors: Bellows‐Riecken Kai H. , Rhodes Ryan E. , Hoffert Krista M.
Published: October 2008

Regular exercise and lifestyle physical activity are often used interchangeably or combined in physical activity messaging based on evidence for their relatively equivalent health outcomes. However, differences between their motivational correlates are relatively unexplored. The purpose of this study was to compare the motives towards lifestyle physical activity and exercise and their relationship with behaviour using the Theory of Planned Behaviour (TPB). The participants were a sample of undergraduate students (n=150) who completed measures of the TPB framed in terms of exercise and lifestyle physical activity and self‐reported physical activity measures with similar framing. Results identified marked differences between the instrumental attitudes towards the two activities showing instrumental attitudes towards exercise to be higher (P<0.01; d=0.68). Most importantly, exercise had larger TPB–behaviour correlations (P<0.01; q=0.15–0.20) compared with lifestyle physical activity, but follow‐up analyses by intensity (strenuous, moderate, mild) showed that these differences were only present at strenuous intensity. Our results suggest that the correlates for the two types of physical activity may differ. Although more research is necessary, this may affect the efficacy of promotion campaigns that do not tailor content exclusively for either exercise or lifestyle physical activity.
Childhood single skinfold thickness is a better predictor for adult relative fat mass in females than the body mass index: Data from a 30‐year longitudinal growth study
Authors: Taeymans Jan , Hebbelinck Marcel , Borms Jan , Clarys Peter , Duquet William ,   (IN MEMORIAM)
Published: October 2008

Information on the prediction of adult relative fat mass (percent body fat,%BF) using measures from pre‐pubertal ages and early childhood is scarce. In the present longitudinal study, we assess the development of different anthropometric indicators of percent body fat during childhood, adolescence, and adulthood in 37½‐year‐old females stratified for low and high percent body fat. Consequently, we study the predictability of percent body fat based on simple anthropometric measurements during childhood and adolescence.

Anthropometric data from the Belgian longitudinal experimental growth study “LEGS” were used. Beginning in 1969, five yearly cohorts of about 100 individuals each (mean age 6 years) were recruited in public kindergartens. Of the original 515 participants (260 males, 255 females) that were measured annually from age 6 to 18 years, 59 males and 60 females agreed to participate in a follow‐up study in 2004. During the follow‐up measurements, the participants were invited for a body‐composition assessment by bioelectrical impedance analysis (BIA). We stratified the participants into low (%BF‐BIA < 35%) and high (%BF‐BIA≥35%) relative fat mass samples. Pearson correlations were calculated and used as tracking coefficients. Multiple stepwise linear regression was applied with anthropometric variables at each age separately as predictors for adult percent body fat, expressed as%BF‐BIA, %BF‐Segal, and %BF‐D&W (Durnin & Womersley, 1974).

The results indicate that a single skinfold thickness during adolescence is a better predictor for adult percent body fat than adolescent body mass index. Additionally, our results suggest that this holds during childhood as early as from age 8 onwards. The use of single skinfold measurements as predictors for adult adiposity and obesity is supported by other arguments, including: (1) body mass index as a proxy for overweight does not discriminate between fat mass and fat‐free mass, and (2) an excess of adipose tissue is more strongly associated with morbidity than the body mass index.
The prevalence and recovery of concussed male and female collegiate athletes
Authors: Bloom Gordon A. , Loughead Todd M. , Shapcott Erin J. B. , Johnston Karen M. , Delaney J. Scott
Published: October 2008

The aims of the present study were two‐fold: (1) to examine whether gender and explanatory style influence the number of concussions an athlete has sustained and the amount of time to recover from this type of injury; and (2) to determine whether gender and the type of sport influence the number of and recovery from concussion injuries. University varsity athletes (n=170) who had sustained at least one concussion over the previous 12 months from six sports completed both the Sport History Questionnaire (Delaney, Lacroix, Leclerc, & Johnston, 2000), used to measure concussions, and the Attributional Style Questionnaire (Peterson et al., 1982), used to measure explanatory style. Overall, males sustained more concussions than female athletes (F 1,153=43.92, P<0.05). Regarding the type of concussion, male athletes sustained more unrecognized concussions than female athletes (F 1,168=6.18, P<0.05), but there was no difference between the sexes for recognized concussions (F 1,168=0.44, P>0.05). Male basketball players took longer to recover (mean=6.17 days) than female basketball players (mean=1.15 days). In contrast, female hockey players took longer to recover (mean=9.56 days) than male hockey players (mean=1.00 day). Finally, gender did not influence an athlete's explanatory style.
Interconnected Histories: Holocaust and Empire in the Cultural Imaginary
Authors: Silverman Max
Published: October 2008

Interconnections between fascism and colonialism and between antisemitism and colonial racism, perceived by post-war theorists of racialized violence such as Hannah Arendt and Aimé Césaire, have for a long time fascinated a number of writers and filmmakers in post-war France, yet their works are not often received from this point of view. This article considers Georges Perec's
W ou le souvenir d'enfance
(1975) and Patrick Modiano's
Dora Bruder
(1997) to show how these are not simply post-Holocaust works but contain an overlapping vocabulary, imagery and, ultimately, history of racism, dehumanization and apocalyptic violence which embraces the Holocaust and Empire. It also argues that the interconnections sought by the post-war generation of theorists of modern forms of violence can be more clearly exposed in imaginative works (rather than historical or sociological works) because these blur the frontiers between the literary imagination, memory and history. Repetitions, substitutions and transformations — the very substance of the literary imagination — open up an alternative history (though one announced by Arendt and others), which challenges the compartmentalization of metropolitan history, colonial history and the history of European genocide.
L'Usage de la photographie chez Annie Ernaux
Authors: Cottille-Foley Nora
Published: October 2008

A la suite d'une expérience personnelle tragique — un cancer du sein qui a failli lui coûter la vie, Annie Ernaux publie en mars 2005 un livre surprenant,
L'Usage de la photo
. Jouant sur l'expérimentation littéraire, Ernaux emprunte le pacte référentiel à l'autobiographie, le processus d'analyse en cours à l'autoportrait, ainsi que les caractéristiques propres à la photographie et à la photobiographie pour se lancer dans un questionnement sur le cancer et sur la mort, qu'elle conduit tantôt sur le mode de l'enquête policière, tantôt sur le mode de l'interrogation métaphysique. Choses fortuites, les photographies successives de vêtements abandonnés après l'acte amoureux forment un kaléidoscope de formes et de couleurs qui doivent susciter l'analyse et finalement mener à une révélation épiphanique. Les vêtements vides, à la fois anthropomorphiques et inanimés, l'inquiétante étrangeté d'un tableau de Chirico ornant les murs dépouillés d'un appartement modeste, et une réflexion sur l'épithète argentique qualifiant un type de photographie tombant en désuétude servent tous à suggérer l'étrange relation de l'absence à la présence, évoquant finalement le mystère de la mort. Empruntant la dialectique manichéenne, Ernaux utilise l'image du Saint Suaire pour renforcer le lien entre le corps et l'écriture, désignant
L'Usage de la photo
comme le cénotaphe devant contenir
in absentia
l'analogon corps-corpus de son œuvre. Le texte mène ultimement à la révélation épiphanique d'une re-co-naissance — reconnaissance pour la valeur de la vie, connaissance des mystères de l'absence, co-naissance tout à la fois du texte à deux voix et de Marie à l'écriture. L'article s'inspire des thèses de Philippe Lejeune, Michel Beaujour, Gilles Mora et Roland Barthes en ce qui concerne la discussion des genres littéraires et l'exploitation des caractéristiques inhérentes à la photographie. Les essais de Didi-Huberman informent l'analyse de la relation du fortuit à l'écriture expérimentale et ont fourni l'image du kaléidoscope comme modèle théorique.
Contrasted patterns of age-specific reproduction in long-lived seabirds
Authors: Berman M , Gaillard J.-M , Weimerskirch H
Published: October 2008

While the number of studies providing evidence of actuarial senescence is increasing, and covers a wide range of taxa, the process of reproductive senescence remains poorly understood. In fact, quite high reproductive output until the last years of life has been reported in several vertebrate species, so that whether or not reproductive senescence is widespread remains unknown. We compared age-specific changes of reproductive parameters between two closely related species of long-lived seabirds: the small-sized snow petrelPagodroma nivea, and the medium-sized southern fulmarFulmarus glacialoides. Both are sympatric in Antarctica. We used an exceptional dataset collected over more than 40 years to assess age-specific variations of both breeding probability and breeding success. We found contrasted age-specific reproductive patterns between the two species. Reproductive senescence clearly occurred from 21 years of age onwards in the southern fulmar, in both breeding probability and success, whereas we did not report any decline in the breeding success of the snow petrel, although a very late decrease in the proportion of breeders occurred at 34 years. Such a contrasted age-specific reproductive pattern was rather unexpected. Differences in life history including size or migratory behaviour are the most likely candidates to account for the difference we reported in reproductive senescence between these sympatric seabird species.
Global associations between terrestrial producer and vertebrate consumer diversity
Authors: Jetz Walter , Kreft Holger , Ceballos Gerardo , Mutke Jens
Published: October 2008

In both ecology and conservation, often a strong positive association is assumed between the diversity of plants as primary producers and that of animals, specifically primary consumers. Such a relationship has been observed at small spatial scales, and a begetting of diversity by diversity is expected under various scenarios of co-evolution and co-adaptation. But positive producer–consumer richness relationships may also arise from similar associations with past opportunities for diversification or contemporary environmental conditions, or from emerging properties of plant diversity such as vegetation complexity or productivity. Here we assess whether the producer–consumer richness relationship generalizes from plot to regional scale and provide a first global test of its strength for vascular plants and endothermic vertebrates. We find strong positive richness associations, but only limited congruence of the most diverse regions. The richness of both primary and higher-level consumers increases with plant richness at similar strength and rate. Environmental conditions emerge as much stronger predictors of consumer richness, and after accounting for environmental differences little variation is explained by plant diversity. We conclude that biotic interactions and strong local associations between plants and consumers only relatively weakly scale up to broad geographical scales and to functionally diverse taxa, for which environmental constraints on richness dominate.
Experimental evolution of a microbial predator's ability to find prey
Authors: Hillesland Kristina L , Velicer Gregory J , Lenski Richard E
Published: October 2008

Foraging theory seeks to explain how the distribution and abundance of prey influence the evolution of predatory behaviour, including the allocation of effort to searching for prey and handling them after they are found. While experiments have shown that many predators alter their behaviour phenotypically within individual lifetimes, few have examined the actual evolution of predatory behaviour in light of this theory. Here, we test the effects of prey density on the evolution of a predator's searching and handling behaviours using a bacterial predator,
Myxococcus xanthus
. Sixteen predator populations evolved for almost a year on agar surfaces containing patches of
Escherichia coli
prey at low or high density. Improvements in searching rate were significantly greater in those predators that evolved at low prey density. Handling performance also improved in some predator populations, but prey density did not significantly affect the magnitude of these gains. As the predators evolved greater foraging proficiency, their capacity diminished to produce fruiting bodies that enable them to survive prolonged periods of starvation. More generally, these results demonstrate that predators evolve behaviours that reflect at least some of the opportunities and limitations imposed by the distribution and abundance of their prey.
De novo mRNA synthesis is required for both consolidation and reconsolidation of fear memories in the amygdala
Authors: Duvarci Sevil , Nader Karim , LeDoux Joseph E.
Published: October 2008

Memory consolidation is the process by which newly learned information is stabilized into long-term memory (LTM). Considerable evidence indicates that retrieval of a consolidated memory returns it to a labile state that requires it to be restabilized. Consolidation of new fear memories has been shown to require de novo RNA and protein synthesis in the lateral nucleus of the amygdala (LA). We have previously shown that de novo protein synthesis in the LA is required for reconsolidation of auditory fear memories. One key question is whether protein synthesis during reconsolidation depends on already existing mRNAs or on synthesis of new mRNAs in the amygdala. In the present study, we examined the effect of mRNA synthesis inhibition during consolidation and reconsolidation of auditory fear memories. We first show that intra-LA infusion of two different mRNA inhibitors dose-dependently impairs long-term memory but leaves short-term memory (STM) intact. Next, we show that intra-LA infusion of the same inhibitors dose-dependently blocks post-reactivation long-term memory (PR-LTM), whereas post-reactivation short-term memory (PR-STM) is left intact. Furthermore, the same treatment in the absence of memory reactivation has no effect. Together, these results show that both consolidation and reconsolidation of auditory fear memories require de novo mRNA synthesis and are equally sensitive to disruption of de novo mRNA synthesis in the LA.
A limited role for the hippocampus in the modulation of novel-object preference by contextual cues
Authors: Piterkin Pavel , Cole Emily , Cossette Marie-Pierre , Gaskin Stephane , Mumby Dave G.
Published: October 2008

Recent evidence suggests that rats require an intact hippocampus in order to recognize familiar objects when they encounter them again in a different context. The two experiments reported here further examined how changes in context affect rats' performance on the novel-object preference (NOP) test of object-recognition memory, and how those effects interact with the effects of HPC damage. Rats with HPC lesions and control rats received NOP testing in either the same context in which they had previously encountered sample objects, or in a different but equally familiar context. In Experiment 1, the two contexts had very few overlapping cues within or outside the apparatus; thus, the differences between them were global. Consistent with previous results, control rats showed a novel-object preference in both the unchanged and (globally) changed contexts, whereas rats with HPC lesions displayed a preference only in the unchanged context. In Experiment 2, the context shift included only local features proximal to the test objects. The main results were the reverse of Experiment 1—rats with HPC lesions displayed a novel-object preference in both the unchanged and (locally) changed contexts, whereas control rats displayed a preference only in the unchanged context. The findings are consistent with the view that HPC damage does not cause a general inability to recognize objects, nor an inability to encode or store a representation of the context in which the objects are encountered. They suggest instead that HPC damage impairs the ability to remember specific locations of familiar objects within a particular context.
Fear relevancy, strategy use, and probabilistic learning of cue-outcome associations
Authors: Thomas Laura A. , LaBar Kevin S.
Published: October 2008

The goal of this study was to determine how the fear relevancy of outcomes during probabilistic classification learning affects behavior and strategy use. Novel variants of the “weather prediction” task were created, in which cue cards predicted either looming fearful or neutral outcomes in a between-groups design. Strategy use was examined by goodness-of-fit estimates of response patterns across trial blocks to mathematical models of simple, complex, and nonidentifiable strategies. Participants in the emotional condition who were fearful of the outcomes had greater skin conductance responses compared with controls and performed worse, used suboptimal strategies, and had less insight into the predictive cue features during initial learning. In contrast, nonfearful participants in the emotional condition used more optimal strategies than the other groups by the end of the two training days. Results have implications for understanding how individual differences in fear relevancy alter the impact of emotion on feedback-based learning.
Role of the phosphoinositide 3-kinase-Akt-mammalian target of the rapamycin signaling pathway in long-term potentiation and trace fear conditioning memory in rat medial prefrontal cortex
Authors: Sui Li , Wang Jing , Li Bao-Ming
Published: October 2008

Phosphatidylinositol 3-kinase (PI3K) and its downstream targets, including Akt (also known as protein kinase B, PKB), mammalian target of rapamycin (mTOR), the 70-kDa ribosomal S6 kinase (p70S6k), and the eukaryotic initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1), may play important roles in long-term synaptic plasticity and memory in many brain regions, such as the hippocampus and the amygdala. The present study investigated the role of the PI3K/Akt-mTOR signaling pathway in the medial prefrontal cortex (mPFC), also a crucial neural locus for the control of cognition and emotion. Western blot analysis of mPFC tissues showed an activation of phosphorylation of Akt at the Ser473 residues, mTOR, p70S6k, and 4E-BP1 in response to long-term potentiation (LTP)-inducing high-frequency stimulation (HFS). Infusion of PI3K inhibitors (wortmannin and LY294002) and an mTOR inhibitor (rapamycin) into the mPFC in vivo suppressed HFS-induced LTP as well as the phosphorylation of PI3K/Akt-mTOR signaling pathway. In parallel, these inhibitors interfered with the long-term retention of trace fear memory examined 3 d and 6 d after the trace fear conditioning training, whereas short-term trace fear memory and object recognition memory were kept intact. These results provide evidence of involvement of activation of the PI3K/Akt-mTOR signaling pathway in the mPFC for LTP and long-term retention of trace fear memory.
The neural correlates of reward-related trial-and-error learning: An fMRI study with a probabilistic learning task
Authors: Koch Kathrin , Schachtzabel Claudia , Wagner Gerd , Reichenbach Jürgen R. , Sauer Heinrich , Schlösser Ralf
Published: October 2008

This fMRI study investigated the neural correlates of reward-related trial-and-error learning in association with changing degrees of stimulus–outcome predictabilities. We found that decreasing predictability was associated with increasing activation in a frontoparietal network. Only maximum predictability was associated with signal decreases across the learning process. The receipt of monetary reward revealed activation in the striatum and associated frontoparietal regions. Present data indicate that during reward-related learning, high uncertainty forces areas relevant for cognitive control to remain activated. In contrast, learning on the basis of predictable stimulus–outcome associations enables the brain to reduce resources in association with the processes of prediction.
Persistent ERK activation maintains learning-induced long-lasting modulation of synaptic connectivity
Authors: Cohen-Matsliah Sivan Ida , Seroussi Yaron , Rosenblum Kobi , Barkai Edi
Published: October 2008

Pyramidal neurons in the piriform cortex from olfactory-discrimination (OD) trained rats undergo synaptic modifications that last for days after learning. A particularly intriguing modification is reduced paired-pulse facilitation (PPF) in the synapses interconnecting these cells; a phenomenon thought to reflect enhanced synaptic release. The molecular machinery underlying this prolonged physiological modulation of synaptic connectivity is yet to be described. We have recently shown that extracellular regulated kinase (ERK) pathway and protein kinase C (PKC) are also required for learning-induced enhancement of intrinsic neuronal excitability. Here we examine whether these signal-transduction cascades are instrumental for the learning-induced, long-lasting PPF reduction. Days after learning completion, PD98059, a selective inhibitor of MEK, the upstream kinase of ERK, increased PPF in neurons from trained, but not in neurons from naïve and pseudo-trained rats. Consequently, the differences in PPF between neurons from trained rats and controls were abolished. The level of activated ERK in synaptoneurosomes was significantly higher in piriform cortex samples prepared from trained rats. Notably, ERK activation revealed that PPF reduction lags behind ERK activation by 2 d. Similarly, the PKC blocker, GF-109203X, enhanced PPF in neurons from trained rats only, thus abolishing the differences between groups. Interestingly, the PKC activator, OAG, had no effect, indicating that PKC activation is required, but not sufficient for long-lasting PPF reduction. Our data show that persistent ERK activation has a key role in maintaining learning-induced PPF reduction for days. This time frame of compartmental ERK-dependent synaptic modulation suggests a novel role for ERK in cortical function.
Age-related declines in general cognitive abilities of Balb/C mice are associated with disparities in working memory, body weight, and general activity
Authors: Matzel Louis D. , Grossman Henya , Light Kenneth , Townsend David , Kolata Stefan
Published: October 2008

A defining characteristic of age-related cognitive decline is a deficit in general cognitive performance. Here we use a testing and analysis regimen that allows us to characterize the general learning abilities of young (3–5 mo old) and aged (19–21 mo old) male and female Balb/C mice. Animals’ performance was assessed on a battery of seven diverse learning tasks. Aged animals exhibited deficits in five of the seven tasks and ranked significantly lower than their young counterparts in general learning abilities (aggregate performance across the battery of tasks). Aging added variability to common core performance (i.e., general learning ability), which translated into increased variability on the individual cognitive tasks. Relatedly, general learning abilities did not differ between the two ages among the best quartile of learners (i.e., cognitive abilities were spared in a subsample of the aged animals). Additionally, working memory capacity (resistance to interference) and duration (resistance to decay) accounted for significantly more of the variability in general learning abilities in aged relative to young animals. Tests of 15 noncognitive performance variables indicated that an increase in body weight (and an associtaed decrease in general activity) was characteristic of those aged animals which exhibited deficient general learning abilities. These results suggest the possibility that general cognitive deficits in aged animals reflect a failure of specific components of the working memory system, and may be related to variations in body weight and an associated decrease in activity.
Clinical trial: the effect of Johrei on symptoms of patients with functional chest pain
Authors: GASIOROWSKA A. , NAVARRO‐RODRIGUEZ T. , DICKMAN R. , WENDEL C. , MOTY B. , POWERS J. , WILLIS M. R. , KOENIG K. , IBUKI Y. , THAI H. , FASS R.
Published: October 2008

Background  Patients with functional chest pain (FCP) represent a therapeutic challenge for practising physicians.

Aim  To determine the efficacy of Johrei as compared to wait‐list in improving symptoms of FCP patients.

Methods  Patients with chest pain of noncardiac origin for at least 3 months were enrolled into the study. All patients had to have negative upper endoscopy, pH testing and oesophageal manometry prior to randomization. Subsequently, patients were randomized to either Johrei or wait‐list control. Patients received 18 Johrei sessions from a Johrei practitioner for 6 weeks.

Results  A total of 21 FCP patients enrolled into the Johrei group and 18 into the wait‐list group. There was no difference in symptom intensity score between Johrei group and wait‐list group at baseline (20.28 vs. 23.06, P = N.S.). However, there was a significant pre‐ and post‐treatment reduction in symptom intensity in the Johrei group (20.28 vs. 7.0, P = 0.0023). There was no significant reduction in symptom intensity score between baseline and at the end of the study in the wait‐list group (23.06 vs. 20.69, P = N.S.).

Conclusion  This pilot study shows that Johrei may have a role in improving FCP symptoms; however, future studies are needed to compare Johrei treatment with sham Johrei or supportive care.
Systematic review on the effectiveness of caffeine abstinence on the quality of sleep
Authors: Sin Celia WM , Ho Jacqueline SC , Chung Joanne WY
Published: October 2008

Aim.  The aim of the present study is to review the effects of caffeine abstinence on the quality of sleep.

Background.  Insomnia is a common problem and abstinence from caffeine is the most popular component in sleep hygiene advice. However, there have been inconsistent results relating to the effectiveness of caffeine abstinence in improving sleep.

Design.  Systematic review.

Methods.  We browsed several electronic databases and reference lists of articles about the correlation of caffeine consumption and sleep deprivation. We selected the articles according to predefined inclusion and exclusion criteria. Two reviewers assessed the quality of trials, which were selected according to the Jadad quality assessment scale. We included the trials scoring three or above in the systematic review and extracted their data. We assessed the heterogeneity of the studies before we considered whether or not to combine the studies’ results.

Results.  Three randomised control trials fulfilled the selection criteria among which two trials scored ≥3 on the Jadad scale. We included these two trials in our systematic review. The designs and outcome measurements of these two trials were not homogeneous, therefore, we did not combine their results. Instead, we conducted a critical appraisal. In one trial, caffeine abstinence was associated with significant lengthening of sleep duration (p < 0·01) and better sleep quality (p < 0·05). In another trial, subjects had less difficulty falling asleep on days when they drank decaffeinated coffee (p < 0·05).

Conclusions.  The results showed that caffeine abstinence for a whole day could improve sleep quality. Thus, health practitioners were recommended to include caffeine abstinence in the instructions for sleep hygiene.

Relevance to clinical practice.  This study demonstrates the effectiveness of caffeine abstinence in improving sleep quality. It provides evidence for the practice of including caffeine abstinence in sleep hygiene advice.
Modulation of syllable period‐selective phonotaxis by prothoracic neurones in crickets (Acheta domesticus): juvenile hormone, picrotoxin and photoinactivation of the ON1 neurones
Authors: ATKINS GORDON , KILMER JASON , SCALFANI MICHEAL , NAVIA BENJAMIN , STOUT JOHN
Published: October 2008

Abstract In response to model calling songs (CSs), the phonotaxis of female Acheta domesticus ranges from being very selective to unselective. Within 15 min of nanoinjecting juvenile hormone III (JHIII) or picrotoxin (PTX) into the prothoracic ganglion, females become more selective for syllable period (SP) than in pre‐tests. Controls for JHIII experiments, including nanoinjection of acetone into the prothoracic ganglion or nanoinjection of JHIII into the metathoracic ganglion, do not influence selectivity. Similarly, nanoinjection of saline into the prothoracic ganglion and nanoinjection of PTX outside of the prothoracic ganglion does not change the overall selectivity of the female’s phonotaxis. These results indicate that circuits in the prothoracic ganglion modulate the SP‐selectivity of phonotaxis.

Photoinactivating both of the ON1 prothoracic auditory interneurones in old females that were previously unselective for SP also results in greater SP‐selectivity during phonotaxis. Evidence suggesting that ON1 has this effect via its inhibitory input to L3 (another prothoracic auditory neurone) includes: photoinactivation of one ON1 neurone causes angular errors in the female’s orientation to CSs at 85 dB (above the threshold of the L3), stimulation with 60 dB CSs (above the threshold of ON1 but below the threshold of L3) does not induce errors in angular orientation, inactivation of ON1 in old crickets results in greater angular errors (85 dB stimulus) than it does when ON1 is inactivated in young females, and photoinactivation of ON1 increases the firing rate of the L3 neurone.
High nocturnal CO2 emanation guides the sand fly Phlebotomus papatasi to sugar‐rich plants
Authors: SCHLEIN YOSEF , JACOBSON RAYMOND L.
Published: October 2008

Abstract In arid areas, Phlebotomus papatasi obtains essential carbohydrates by feeding on green tissues of plants. There is a great variation in sugar content, metabolic rates and dark respiration between conspecific plants, and also between branches and leaves of the same plant. It is hypothesized that high nocturnal release of CO2 may guide the sand flies to rich sugar sources. Comparisons of Ph. papatasi feeding on branches of different plant species demonstrate a significant positive correlation between the level of sugar in leaves, the rate of sand fly feeding on them and the size of ingested sugar meals. Mean nocturnal CO2 emanation of low‐sugar Ricinus communis branches is 26.5 ppm and that of sugar rich branches is 86.3 ppm above room level. Low‐sugar Capparis spinosa branches release 45.0 ppm and the emission from sugar rich branches is 76.0 ppm above room level. Branches with similar emissions, placed behind net partitions, are used in no‐choice orientation experiments: R. communis branches releasing high CO2 levels are approached by 53.7% of the flies compared with 3.0% of flies that orientate to low CO2 branches. Capparis spinosa with high CO2 emission are approached by 9.8% of the flies compared with 0.95% of flies that orientate to low CO2 branches.
Competition strategies and correlated selection on responses to polyandry in the seed beetle Callosobruchus maculatus
Authors: GUEDES RAUL NARCISO C. , SMITH ROBERT H.
Published: October 2008

Abstract Polyandry reflected in multiple mating with different mates is regarded as favoured by natural selection in males but not necessarily in females, where conflicting effects on fitness components can occur. The present study aims to provide empirical evidence to predict which fitness components may be affected in this sexual conflict using a species that demonstrates potential between‐population variation in their resolution: the cowpea weevil Callosobruchus maculatus. Two strains showing contrasting competition outcomes (scramble × contest) and contrasting life‐history strategies based on trade‐offs between longevity and fecundity are crossed for subsequent selection based on larval‐competition strategy, expecting the production of a correlated response to multiple (polyandrous) mating. Such a response is expected because the scramble strain shows high fecundity (and lower longevity) and would benefit from multiple mating, in contrast with the contest strain, which shows high juvenile mortality. The scramble‐selected lines would evolve a response of increased fecundity and reduced longevity under multiple and potentially polyandrous mating but the contest‐selected lines would not respond to multiple (polyandrous) mating. Instead, both scramble‐ and contest‐selected lines show increased fecundity and reduced longevity with multiple (polyandrous) matings, which did not affect egg weight. Indirect benefits of multiple (polyandrous) mating appear to be relevant for lines showing contest competition among juveniles.
Exhaustion of the chloroplast protein synthesis capacity by massive expression of a highly stable protein antibiotic
Authors: Oey Melanie , Lohse Marc , Kreikemeyer Bernd , Bock Ralph
Published: October 2008

Plastids (chloroplasts) possess an enormous capacity to synthesize and accumulate foreign proteins. Here we have maximized chloroplast protein production by over‐expressing a proteinaceous antibiotic against pathogenic group A and group B streptococci from the plastid genome. The antibiotic, a phage lytic protein, accumulated to enormously high levels (>70% of the plant’s total soluble protein), and proved to be extremely stable in chloroplasts. This massive over‐expression exhausted the protein synthesis capacity of the chloroplast such that the production of endogenous plastid‐encoded proteins was severely compromised. Our data suggest that this is due to translational rather than transcriptional limitation of gene expression. We also show that the chloroplast‐produced protein antibiotic efficiently kills the target bacteria. These unrivaled expression levels, together with the chloroplast’s insensitivity to enzymes that degrade bacterial cell walls and the elimination of the need to remove bacterial endotoxins by costly purification procedures, indicate that this is an effective plant‐based production platform for next‐generation antibiotics, which are urgently required to keep pace with rapidly emerging bacterial resistance.
BC10, a DUF266‐containing and Golgi‐located type II membrane protein, is required for cell‐wall biosynthesis in rice (Oryza sativa L.)
Authors: Zhou Yihua , Li Shengben , Qian Qian , Zeng Dali , Zhang Mu , Guo Longbiao , Liu Xiangling , Zhang Baocai , Deng Lingwei , Liu Xinfang , Luo Guanzheng , Wang Xiujie , Li Jiayang
Published: October 2008

Glycosyltransferases (GTs) are one of the largest enzyme groups required for the synthesis of complex wall polysaccharides and glycoproteins in plants. However, due to the limited number of related mutants that have observable phenotypes, the biological function(s) of most GTs in cell‐wall biosynthesis and assembly have remained elusive. We report here the isolation and in‐depth characterization of a brittle rice mutant, brittle culm 10 (bc10). bc10 plants show pleiotropic phenotypes, including brittleness of the plant body and retarded growth. The BC10 gene was cloned through a map‐based approach, and encodes a Golgi‐located type II membrane protein that contains a domain designated as ‘domain of unknown function 266’ (DUF266) and represents a multiple gene family in rice. BC10 has low sequence similarity with the domain to a core 2 β‐1,6‐N‐acetylglucosaminyltransferase (C2GnT), and its in vitro enzymatic activity suggests that it functions as a glycosyltransferase. Monosaccharide analysis of total and fractioned wall residues revealed that bc10 showed impaired cellulose biosynthesis. Immunolocalization and isolation of arabinogalactan proteins (AGPs) in the wild‐type and bc10 showed that the level of AGPs in the mutant is significantly affected. BC10 is mainly expressed in the developing sclerenchyma and vascular bundle cells, and its deficiency causes a reduction in the levels of cellulose and AGPs, leading to inferior mechanical properties.
Unique glycine‐activated riboswitch linked to glycine–serine auxotrophy in SAR11
Authors: Tripp H. James , Schwalbach Michael S. , Meyer Michelle M. , Kitner Joshua B. , Breaker Ronald R. , Giovannoni Stephen J.
Published: October 2008

The genome sequence of the marine bacterium ‘Candidatus Pelagibacter ubique’ and subsequent analyses have shown that while it has a genome as small as many obligate parasites, it nonetheless possesses a metabolic repertoire that allows it to grow as one of the most successful free‐living cells in the ocean. An early report based on metabolic reconstruction indicated that SAR11 cells are prototrophs for all amino acids. However, here we report experimental evidence that ‘Cand. P. ubique’ is effectively auxotrophic for glycine and serine. With glucose and acetate added to seawater to supply organic carbon, the addition of 125 nM to 1.5 μM glycine to growth medium containing all other nutrients in excess resulted in a linear increase in maximum cell density from 1.14 × 106 cells ml−1 to 8.16 × 106 cells ml−1 (R2 =  0.992). Serine was capable of substituting for glycine at 1.5 μM. ‘Cand. P. ubique’ contains a glycine‐activated riboswitch preceding malate synthase, an unusual genomic context that is conserved in the SAR11 group. Malate synthase plays a critical role in central metabolism by enabling TCA intermediates to be regenerated through the glyoxylate cycle. In vitro analysis of this riboswitch indicated that it responds solely to glycine but not close structural analogues, such as glycine betaine, malate, glyoxylate, glycolate, alanine, serine or threonine. We conclude that ‘Cand. P. ubique’ is therefore a glycine–serine auxotroph that appears to use intracellular glycine level to regulate its use of carbon for biosynthesis and energy. Comparative genomics and metagenomics indicate that these conclusions may hold throughout much of the SAR11 clade.
Testing for endemism, genotypic diversity and species concepts in Antarctic terrestrial microalgae of the Tribonemataceae (Stramenopiles, Xanthophyceae)
Authors: Rybalka Nataliya , Andersen Robert A. , Kostikov Igor , Mohr Kathrin I. , Massalski Andrzej , Olech Maria , Friedl Thomas
Published: October 2008

The genetic diversity of all available culture strains of the Tribonemataceae (Stramenopiles, Xanthophyceae) from Antarctica was assessed using the chloroplast‐encoded psbA /rbcL spacer region sequences, a highly variable molecular marker, to test for endemism when compared with their closest temperate relatives. There was no species endemic for Antarctica, and no phylogenetic clade corresponded to a limited geographical region. However, species of the Tribonemataceae may have Antarctic populations that are distinct from those of other regions because the Antarctic strain spacer sequences were not identical to sequences from temperate regions. Spacer sequences from five new Antarctic isolates were identical to one or more previously available Antarctic strains, indicating that the Tribonemataceae diversity in Antarctic may be rather limited. Direct comparisons of the spacer sequences and phylogenetic analyses of the more conserved rbcL gene revealed that current morphospecies were inadequate to describe the actual biodiversity of the group. For example, the genus Xanthonema, as currently circumscribed, was paraphyletic. Fortunately, the presence of distinctive sequence regions within the psbA/rbcL spacer, together with differences in the rbcL phylogeny, provided significant autoapomorphic criteria to re‐define the Tribonemataceae species.
Going with the Grain in African Development?
Authors: Kelsall Tim
Published: October 2008

In view of the disappointing performance of the Good Governance agenda in Africa, policy‐makers are asking whether better results could be obtained with approaches that attempt to ‘work with the grain’ of African societies. This article explores what this might mean. It identifies a core set of beliefs and values – concerning power, accountability and social morality – that have proved extremely durable and remain powerful drivers of behaviour across sub‐Saharan Africa. It finds that, in general, Western institutions sit ill with these traditions. The question is, therefore, how to redirect development efforts so that they stop working against, and start to build upon, the extant notions of moral obligation and interpersonal accountability in the region.
Agro‐Food Preferences in the EU's GSP Scheme: An Analysis of Changes Between 2004 and 2006
Authors: DeMaria Federica , Drogué Sophie , Matthews Alan
Published: October 2008

This article examines the extent to which the 2006 revisions to the EU's Generalised System of Preferences improved market‐access opportunities for developing‐country agro‐food exports. It shows that they resulted in only a slight increase in the percentage preferential margin, but that there has been a significant increase in the value of preferential trade and of the preferential margin enjoyed by exporters. This was accompanied by changes in the ranking of beneficiaries. Countries such as China, Brazil, Argentina, India and South Africa maintained their significant shares of GSP agro‐food exports, but other countries such as Thailand and Vietnam have now emerged as major GSP beneficiaries.
The Linkages Between FDI and Domestic Investment: Unravelling the Developmental Impact of Foreign Investment in Sub‐Saharan Africa
Authors: Ndikumana Léonce , Verick Sher
Published: October 2008

While the recent increase in foreign direct investment (FDI) to African countries is a welcome development, the impact of these resource inflows on economic development remains in doubt. This article argues that a key channel is its effects on domestic factor markets, especially domestic investment, and analyses the two‐way linkages between FDI and domestic investment in sub‐Saharan Africa. The results suggest, first, that FDI crowds in domestic investment and, secondly, that private investment is a driver of FDI, implying that African countries will gain much from improving the domestic climate. Moreover, there are alternatives to resource endowments as a means of attracting foreign investment to non‐resource‐rich countries.
The Conundrum of Low Saving Rates in Latin America
Authors: Reinhardt Nola
Published: October 2008

Despite extensive economic reforms during the late 1980s/early 1990s, Latin America's saving rates remain low. This article examines the saving behaviour of 18 Latin American countries in the 1976‐2000 period and compares it with that of 25 other developing countries. It finds that lower inflation, income growth and increased real interest rates on deposits have not had the expected effects on saving rates in Latin America. Instead, the determinants of saving behaviour appear to differ between the two groups of countries, and saving rates are affected by a degree of inertia. Although more research is needed, this indicates that the focus of the neoliberal economic reforms of the 1980s was misplaced.
Understanding learner acceptance of learning objects: The roles of learning object characteristics and individual differences
Authors: Lau Siong‐Hoe , Woods Peter C.
Published: October 2008

Many organisations and institutions have integrated learning objects into their e‐learning systems to make the instructional resources more efficient. Like any other information systems, this trend has made user acceptance of learning objects an increasingly critical issue as a high level of learner satisfaction and acceptance reflects that the users are more willing to continue to use the technology. In this study, an extended version of technology acceptance model (TAM) with two external variables (learning object characteristics and individual differences) was developed to investigate the underlying factors and causal relationships in predicting learners' acceptance of learning objects. This study called for the respondents to progress through two phases of learning object participation: introduction and direct‐use experience to investigate the students' perceptions in terms of usefulness and ease of use while utilising learning objects. The findings show that both perceived usefulness and perceived ease of use are determinants of behavioural intention to use learning objects. Learning object characteristics influence both perceived usefulness and perceived ease of use of learning objects; individual differences appear to have no influence upon intention to use learning objects.
Rubrics for designing and evaluating online asynchronous discussions
Authors: Penny Lana , Murphy Elizabeth
Published: October 2008

The purpose of the study reported on in this paper was to identify performance criteria and ratings in rubrics designed for the evaluation of learning in online asynchronous discussions (OADs) in post‐secondary contexts. We analysed rubrics collected from Internet sources. Using purposive sampling, we reached saturation with the selection of 50 rubrics. Using keyword analysis and subsequent grouping of keywords into categories, we identified 153 performance criteria in 19 categories and 831 ratings in 40 categories. We subsequently identified four core categories as follows: cognitive (44.0%), mechanical (19.0%), procedural/managerial (18.29%) and interactive (17.17%). Another 1.52% of ratings and performance criteria were labelled vague and not assigned to any core category.
Facilitating Asian students' critical thinking in online discussions
Authors: Chiu Yi‐Ching Jean
Published: October 2008

The purpose of the study reported here is to illustrate how an approach based on a culturally appropriate ‘shepherd metaphor’ has helped Asian students to cross cultural boundaries and to engage in critical thinking online. Asian students are under different levels of influence from the Confucian Heritage Culture, which cultivates students to revere authority, maintain harmony and avoid conflicts in public. This has a significant impact on Asian students' cultural readiness to verbalise critical thinking. This paper partially reports research undertaken in a large English as a Foreign Language reading class in Taiwan, in which ‘shepherd leadership’ was practised. Shepherd leadership involves knowing students individually, offering cognitive modelling, exercising leadership and discipleship, encouraging student leadership and calling on silent students personally to get them to participate. This approach, concentrating on Asian students' affective needs, cognitive modelling, passing leadership to students and reaching out to silent ones, was found effective.