bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychological problems, protective factors and health‐related quality of life in youth affected by violence: The burden of the multiply victimised
Authors: Schlack Robert , Ravens‐Sieberer Ulrike , Petermann Franz
Published: April 2013

This study investigates self‐rated mental health in terms of psychological problems, protective factors and health‐related quality of life (HRQOL) in a nationally representative sample of adolescents (n = 6813) aged 11–17 involved in violence with varying frequency. Using MANCOVA and ANCOVA, youth with single and multiple histories of violent victimisation and violence perpetration were contrasted with non‐involved comparisons. The results show that even low levels of violence involvement were associated with more problems, fewer protective factors and impaired HRQOL. Multiply victimised youth – not perpetrating victims – stood out with internalising, peer and hyperactivity/inattention problems. Discriminant function analysis separated non‐involved from violence‐affected youth, and multiply victimised from not multiply victimised youth. Externalising behaviours, family issues, male sex and school functioning predicted group separation on the first function (proportion variance explained 80.0%), while internalising and peer issues were predictive for the second function (PVE 14.2%). Implications for prevention, intervention and research are discussed.
Optimal shapes for anguilliform swimmers at intermediate Reynolds numbers
Authors: van Rees Wim M. , Gazzola Mattia , Koumoutsakos Petros
Published: April 2013

We investigate the optimal morphologies for fast and efficient anguilliform swimmers at intermediate Reynolds numbers, by combining an evolution strategy with three-dimensional viscous vortex methods. We show that anguilliform swimmer shapes enable the trapping and subsequent acceleration of regions of fluid transported along the entire body by the midline travelling wave. A sensitivity analysis of the optimal morphological traits identifies that the width thickness in the anterior of the body and the height of the caudal fin are critical factors for both speed and efficiency. The fastest swimmer without a caudal fin, however, still retains 80 % of its speed, showing that the entire body is used to generate thrust. The optimal shapes share several features with naturally occurring morphologies, but their overall appearances differ. This demonstrates that engineered swimmers can outperform biomimetic swimmers for the criteria considered here.
THE PRINCIPLE OF DEMOCRACY IN THE CASE LAW OF THE EUROPEAN COURT OF JUSTICE
Authors: Lenaerts Koen
Published: April 2013

This article seeks to explore the way in which the Court of Justice of the European Union (‘CJEU’) has interpreted and applied the principle of democracy. It examines first the democratization process upon which the EU has embarked since the adoption of the Treaty of Maastricht and how that transformation was a positive reaction to those voices arguing that the EU suffers from a ‘democratic deficit’. Next, it is argued that the CJEU has understood the principle of democracy in a way which is respectful of the two sources of democratic legitimacy at EU level, namely the Member States and the peoples of Europe. Accordingly, that understanding of the principle of democracy is illustrated by some relevant examples taken from the case law of the CJEU and the European General Court (‘EGC’). Those examples show that the CJEU has strived to protect the prerogatives of the European Parliament, the only political institution of the EU whose members have, since 1979, been elected for a term of five years by direct universal suffrage in a free and secret ballot. Yet, they also show that the principle of democracy is not limited to protecting parliamentary prerogatives. That principle, like all EU constitutional principles, pervades the whole of EU law and, as such, must be read in light of societal changes. As democracy within the EU is not limited to the participation by the European Parliament in the legislative process but also encompasses other forms of governance, in particular rule-making by administrative agencies and the achievement of consensus by social partners, it is for the EU judiciary to make sure that those other forms of governance remain as democratic as possible. This can be achieved, inter alia, by making sure that they enjoy sufficient representation or are subject to parliamentary control. Furthermore, the CJEU and the EGC also take into account new mechanisms which seek to strengthen the principle of democracy, such as the principle of transparency. In so doing, they aim to enhance the democratic legitimacy of the EU by providing sufficient means for EU citizens to hold their representatives accountable. Finally, it is contended that the principle of democracy, as interpreted by the CJEU, draws inspiration from national democracies. In so doing, the CJEU strives to place national and supranational democracies in a mutually reinforcing relationship.
Locke's Inverted Quarantine: Discipline, Panopticism, and the Making of the Liberal Subject
Authors: Baltes John
Published: April 2013

Some Thoughts Concerning Educationoffers the theory of governance theTwo Treatiseslack. Education is the key to Lockean politics: self-government and public order require virtuous citizens, and these citizens, as Locke suggested in theEssayand explains in theEducation, are made rather than found, constructed from the ground up by discipline. Through early and careful practices of education, they are enmeshed in a net of habit and custom that naturalizes the moral commitments they are taught, rendering the process, and the artifice, invisible. Locke entangles his subjects in an architecture of power of which they become the bearers, thereby providing the foundation for public order and limited government. Locke's disciplinary liberalism allows us to better appreciate late modern subjectivity as an achievement, rather than a given of political life, albeit an achievement that involves some uncomfortable compromises and a willingness to accept, if not laud, our disciplinary commitments.
Excavations in the Acheulean Levels at the Earlier Stone Age Site of Canteen Koppie, Northern Province, South Africa
Authors: McNabb John , Beaumont Peter
Published: April 2013

The fluvial gravels of the river Vaal in South Africa have long been known as a source for Earlier Stone Age (ESA) artefacts. Most were discovered through the open cast mining for diamonds that has left very littlein situfluvial sediment remaining today. The site of Canteen Koppie is an internationally famous location with a reputation for prolific Acheulean artefacts, especially handaxes and the enigmatic prepared core and Levallois-like technology known as Victoria West. Our understanding of this site, and most other Vaal locations, is almost solely based on highly selected artefact collections. Here, we report on the first controlled excavations ever to be conducted at Canteen Koppie. The deposits are likely to date to the Early and Middle Pleistocene, and our excavations sample the full depth of the stratigraphic sequence. The lower units, first identified in these excavations, add a considerable time depth to the Acheulean occupation of the site, making this the longest chrono-stratigraphic sequence in South Africa to our knowledge. Given the current international interest in the origins of Levallois/prepared core technology (PCT), its occurrence in Unit 2b Upper, and its presence alongside Victoria West technology in Unit 2a has significant implications for debates on the role of Victoria West in the origins of PCT. From the Canteen Koppie evidence, Levallois and Victoria West are clearly rooted in the Acheulean.
Bogs, Bodies and Burnt Mounds: Visits to the Soar Wetlands in the Neolithic and Bronze Age
Authors: Ripper Susan , Beamish Matthew , Bayliss A. , Ramsey C. Bronk , Brown A. , Collins M. , Cooper N. J. , Cook G. , Cook J. , Gouldwell A. , Greig J. , Hatton J. , Marshall P.D. , Meadows J. , Monckton A. , Van Der Plicht H. , Smith D. , Tetlow E.
Published: April 2013

The recording and analysis of a burnt mound and adjacent palaeochannel deposits on the floodplain of the River Soar in Leicestershire revealed that the burnt mound was in use, possibly for a number of different purposes, at the transition from the Neolithic to the Bronze Age. An extensive radiocarbon dating programme indicated that the site was revisited. Human remains from the palaeochannel comprised the remains of three individuals, two of whom pre-dated the burnt mound by several centuries while the partial remains of a third, dating from the Late Bronze Age, provided evidence that this individual had met a violent death. These finds, along with animal bones dating to the Iron Age, and the remains of a bridge from the early medieval period, suggest that people were drawn to this location over a long period of time.
Modelling distribution and potential overlap between Boreal Owl Aegolius funereus and Black Woodpecker Dryocopus martius: implications for management and monitoring plans
Authors: BRAMBILLA MATTIA , BASSI ENRICO , BERGERO VALENTINA , CASALE FABIO , CHEMOLLO MARCO , FALCO RICCARDO , LONGONI VIOLETTA , SAPORETTI FABIO , VIGANÒ ENRICO , VITULANO SEVERINO
Published: April 2013

Correlative species distribution models (SDMs) are increasingly widespread in the conservation literature. They can be used for a variety of purposes, including addressing practical conservation tasks on the basis of a spatially explicit assessment of environmental suitability for target taxa, which in turn allows for a transparent evaluation of needs and opportunities. Here we used the maximum entropy method (by means of the software MaxEnt) to model distribution of the rare Boreal Owl Aegolius funereus and the Black Woodpecker Dryocopus martius, which excavates the nest-holes used by the owl for breeding. We believe that monitoring surveys for Boreal Owl should consider areas suitable for both species as priority sites, whereas the provision of nest-boxes for the owl may be particularly desirable in habitat patches that are suitable for that species but not for the keystone species whose nest-holes represent the usual nest site for the owl. Finally, areas suitable for both species can represent priority areas for the conservation of forest birds in the Alps, as both species have been reported as umbrella and/or keystone species. Our example provides a possible framework to model management and monitoring opportunities in other species or species pairs, but such an approach can be used to infer the need for particular management options when both limiting factors and species distribution can be spatially modelled, and also to model the areas where different target species are more likely to overlap and interact. The use of distribution models as tools to address practical conservation tasks should also be encouraged in order to accomplish practical tasks according to sound knowledge and transparent methods.
NON-EVOLUTIONARY DEGENERATION IN ARTHUR MACHEN'S SUPERNATURAL TALES
Authors: Jackson Kimberly
Published: April 2013

Welsh author Arthur Machen (1863–1947) wrote his most popular supernatural tales between 1890 and 1900, a period in which European culture felt itself to be on the decline and in which “decadent” art and literature rose up both as a reflection of and a contribution to this perceived cultural deterioration. While Machen's works have received little critical attention, a recent revival of interest in fin-de-siècle decadence has brought his supernatural tales into the literary limelight. Noteworthy examples of this interest include Julian North's treatment of The Great God Pan in Michael St. John's Romancing Decay: Ideas of Decadence in European Culture and Christine Ferguson's analysis of the same work in her PMLA article “Decadence as Scientific Fulfillment.” Indeed, Machen's supernatural tales could enhance and complicate any exposition of decadent literature and culture; they offer a unique vision of descent into the primordial that differs from the moral and psychological treatment of decadence in other popular works of the time, such as Wilde's The Picture of Dorian Gray and Stevenson's Strange Case of Dr. Jekyll and Mr. Hyde. Like Stevenson and Wilde, Machen employs themes of transgression and metamorphosis to illustrate his characters’ deviations from human nature. However, the forces at work in Machen's tales do not arise from the recesses of the human mind in its modern conception, nor do his protagonists sin primarily against society and the arbitrary nature of its morals and values. Instead, Machen locates mythic forces at work within his contemporary society to highlight a much older form of transgression and to challenge notions of degeneration that held currency at the end of the nineteenth century.
SPATIAL HETEROGENEITY IN SIMPLE DETERMINISTIC SIR MODELS ASSESSED ECOLOGICALLY
Authors: WATERS E. K. , SIDHU H. S. , MERCER G. N.
Published: April 2013

Patchy or divided populations can be important to infectious disease transmission. We first show that Lloyd’s mean crowding index, an index of patchiness from ecology, appears as a term in simple deterministic epidemic models of the SIR type. Using these models, we demonstrate that the rate of movement between patches is crucial for epidemic dynamics. In particular, there is a relationship between epidemic final size and epidemic duration in patchy habitats: controlling inter-patch movement will reduce epidemic duration, but also final size. This suggests that a strategy of quarantining infected areas during the initial phases of a virulent epidemic might reduce epidemic duration, but leave the population vulnerable to future epidemics by inhibiting the development of herd immunity.
A MODIFIED PROJECTED CONJUGATE GRADIENT ALGORITHM FOR UNCONSTRAINED OPTIMIZATION PROBLEMS
Authors: HUANG SHUAI , WAN ZHONG , DENG SONGHAI
Published: April 2013

We propose a modified projected Polak–Ribière–Polyak (PRP) conjugate gradient method, where a modified conjugacy condition and a method which generates sufficient descent directions are incorporated into the construction of a suitable conjugacy parameter. It is shown that the proposed method is a modification of the PRP method and generates sufficient descent directions at each iteration. With an Armijo-type line search, the theory of global convergence is established under two weak assumptions. Numerical experiments are employed to test the efficiency of the algorithm in solving some benchmark test problems available in the literature. The numerical results obtained indicate that the algorithm outperforms an existing similar algorithm in requiring fewer function evaluations and fewer iterations to find optimal solutions with the same tolerance.
Agree or Disagree?
Authors: Pretsch Johanna , Heckmann Nina , Flunger Barbara , Schmitt Manfred
Published: April 2013

Consensus obtained in personality judgments based on thin slices of behavior was examined by manipulating the shared meaning of the traits being judged, the accountability for the judgments, and the amount of target information. 160 judges rated a total of 60 teachers on the Big Five personality dimensions. Consensus was approached from a judge and from a target perspective. A shared meaning had a negative effect on consensus in Extraversion ratings. Accountability had a consistently negative effect across consensus perspectives. A positive effect for amount of target information was found for Neuroticism. Additionally, it was shown that, under different conditions, judgments were based more or less on shared stereotypes. Results suggest that the degree to which we agree on our judgments of others can easily be manipulated by external influences, thus involving significant practical implication for various contexts.
Impairments in Mental Model Construction and Benefits of Defocused Attention
Authors: von Hecker Ulrich , Sedek Grzegorz , Brzezicka Aneta
Published: April 2013

In this article, we examine the hypothesis that cognitive deficits in subclinical depression become especially evident in tasks that require the integration of piecemeal information into more coherent mental representations, such as mental models. It is argued that in states of subclinical depression, attempts at integrative thinking or problem solving are limited by cognitive exhaustion which prevents the use of effective cognitive strategies. This basic argument is illustrated by paradigms addressing the construction of mental models based on sentiment or linear order information. It is shown that subclinical depression is associated with a distinct deficit in integrative reasoning, but no deficits in non-integrative processing such as initial information sampling or memory retrieval. Recent evidence of a neurophysiological correlate of this specific deficit in subclinical depression is discussed in terms of the moderating role of frontal alpha asymmetry, and in terms of a specific pattern of parietal brain activation during processing of mental models. Also, a distinctive, not deficit-related, facet of depressed cognitive symptoms is proposed, indicating a possible adaptive value of defocused attention in subclinically depressed mood. This defocused attention approach is supported by experimental and eyetracking research, and by recent theoretical models and empirical evidence showing performance benefits in depression for some cognitive and creative tasks.
Zymogen activation of neurotrypsin and neurotrypsin-dependent agrin cleavage on the cell surface are enhanced by glycosaminoglycans
Authors: Gisler Claudio , Lüscher Daniel , Schätzle Philipp , Dürr Stephanie , Baici Antonio , Galliciotti Giovanna , Reif Raymond , Bolliger Marc F. , Kunz Beat , Sonderegger Peter
Published: April 2013

The serine peptidase neurotrypsin is stored in presynaptic nerve endings and secreted in an inactive zymogenic form by synaptic activity. After activation, which requires activity of postsynaptic NMDA (N-methyl-D-aspartate) receptors, neurotrypsin cleaves the heparan sulfate proteoglycan agrin at active synapses. The resulting C-terminal 22-kDa fragment of agrin induces dendritic filopodia, which are considered to be precursors of new synapses. In the present study, we investigated the role of GAGs (glycosaminoglycans) in the activation of neurotrypsin and neurotrypsin-dependent agrin cleavage. We found binding of neurotrypsin to the GAG side chains of agrin, which in turn enhanced the activation of neurotrypsin by proprotein convertases and resulted in enhanced agrin cleavage. A similar enhancement of neurotrypsin binding to agrin, neurotrypsin activation and agrin cleavage was induced by the four-amino-acid insert at the y splice site of agrin, which is crucial for the formation of a heparin-binding site. Non-agrin GAGs also contributed to binding and activation of neurotrypsin and, thereby, to agrin cleavage, albeit to a lesser extent. Binding of neurotrypsin to cell-surface glycans locally restricts its conversion from zymogen into active peptidase. This provides the molecular foundation for the local action of neurotrypsin at or in the vicinity of its site of synaptic secretion. By its local action at synapses with correlated pre- and post-synaptic activity, the neurotrypsin–agrin system fulfils the requirements for a mechanism serving experience-dependent modification of activated synapses, which is essential for adaptive structural reorganizations of neuronal circuits in the developing and/or adult brain.
Comparison of ryegrass and red clover on the fermentation pattern, microbial community and efficiency of diet utilisation in the rumen simulation technique (Rusitec)
Authors: Belanche A. , Lee M. R. F. , Moorby J. M. , Newbold C. J.
Published: April 2013

An in vitro experiment was designed to investigate the effects of incubating two forages with a different energy/nitrogen (N) ratio [perennial ryegrass (GR) vs red clover (RC)] on the efficiency of N utilisation by rumen microbes. Second-cut forages were incubated in artificial rumen fermenters (n = 8). Ryegrass represented a supply of quickly available N and energy for the rumen microorganism which led to a rapid fermentation and bacterial growth 2–4 h after feeding. Ryegrass also promoted greater numbers of anaerobic fungi, methanogens and cellulolytic bacteria, which tended to increase neutral detergent fibre disappearance, gas production, volatile fatty acid and methane production than observed using RC diets. On the contrary, RC provided slowly degradable N and energy, which led to a relatively slow bacterial growth (4–8 h after feeding). In terms of diet utilisation, RC diets promoted a higher N outflow (mainly as undegraded-N) and efficiency of microbial protein synthesis per organic matter disappeared. Even so, microbial protein yield was similar on both diets indicating a better N capture by microorganisms fed GR than in those fed RC diets. The use of 15N-labelled forages demonstrated that this high ammonia incorporation by bacteria-fed GR occurred mainly during the early fermentation coinciding with the highest bacterial growth. In conclusion, this experiment demonstrated that the use of isotopic labelling combined with molecular techniques provided an insight into forage utilisation by the rumen microbes; GR diets led to a better efficiency of N utilisation compared with RC; moreover the lower N outflow on GR diets may be partially compensated for a higher proportion of microbial protein leaving the system and the greater volatile fatty acid production. These findings seem to indicate that RC grazing may increase the N pollution compared with GR without substantial improvements on the rumen function, however this must be confirmed in vivo.
Behaviour, illness and management during the periparturient period in dairy cows
Authors: Sepúlveda-Varas P. , Huzzey J. M. , Weary D. M. , von Keyserlingk M. A. G.
Published: April 2013

The periparturient period, typically defined as the period immediately before and after calving, is a challenging time for dairy cattle that must cope with physiological, metabolic and endocrine changes, as well as a variety of environmental and management-related stressors. These challenges likely contribute to the high incidence of disease observed during the weeks following parturition. Changes in behaviour during the period around parturition can be used to identify animals that are ill or at risk of disease. The aim of this review is to summarise current knowledge on the behavioural changes of dairy cattle during the periparturient period and how these changes relate to illness. We provide an overview of the concept of sickness behaviour and describe the normal changes in feeding behaviour, social behaviour, and resting behaviour around parturition and how these behaviours differ between animals that become ill after parturition and those that remain healthy. We also review the literature on behavioural responses to common farm management practices around parturition drawing on examples related to early cow–calf separation, space restriction, social re-grouping, and housing conditions. This review focuses primarily on indoor group-housed dairy cattle as the majority of research has been focussed in this area; however, literature related to pasture-based dairy production, other farm animal species, and rodents is also discussed. Reduced feeding time and intake, increased standing time, restlessness, and a reluctance or inability to successfully compete for access to important resources are examples of the behavioural changes that have been associated with illness after calving. Using behaviour to identify sick cattle and those at increased risk of becoming ill will facilitate prompt treatment and provide opportunities to identify management changes that prevent disease, improving overall herd health and animal welfare.
A method for estimating the economic value of changes in the risk of breech strike
Authors: Horton Brian
Published: April 2013

An economic model of the costs of sheep flystrike has been modified to examine the effect of a given change in the risk of breech strike as if it applied to the entire wool-producing industry, rather than to individual wool producers. Within each region (high rainfall, sheep/cereal and pastoral zones), the model sets the proportion of the sheep population in low, medium and high risk categories and calculates the estimated level of strike for untreated sheep in those groups. The costs related to breech strike can be calculated according to the original model. The risk of breech strike can then be adjusted to any required level, the proportion of sheep in each category adjusted and the costs recalculated according to the adjusted risk. The model estimated that a 50% reduction in the risk of breech strike would decrease the number of sheep requiring preventive treatment to about one-third of previous levels, but only provide a small reduction in costs related to struck sheep, due to the large increase in the number of sheep no longer receiving preventive treatment. There would be only small reductions in costs related to crutching and mulesing sheep unless much larger reductions in strike risk occurred. The overall benefit of a 50% reduction in the risk of strike would be $0.23–0.27 per sheep. If this reduction in strike risk occurred across all regions this could provide a benefit to the Australian sheep industry of $15 million. The model found that if mulesing was not used in any of the sheep then the use of preventive treatment would increase so that 93% rather than only 60% received chemical treatment, and reduction of the risk of breech strike by 50% provided benefits of $0.40 per sheep. Therefore, the estimated benefits would be greater than $0.27 per sheep in situations where the current level of risk is very high.
Evaluation of an electronic system for automatic calving detection on a dairy farm
Authors: Marchesi G. , Leonardi S. , Tangorra F. M. , Calcante A. , Beretta E. , Pofcher E. , Lazzari M.
Published: April 2013

Precise calving monitoring is important for reducing the effects of dystocia in cows and calves. The C6 birth control system is an electronic device that detects the time of the expulsion phase during calving. Several 53 Holstein were fitted on Day 280 ± 5 of gestation with the C6 birth control system, which was left in place until confirmation of calving. Sensitivity and PPV of the system were calculated as 100 and 95%, respectively. The partum events occurring at the group fitted with the system where compared with the analogous occurred at 59 animals without device. When alarmed by the system farm staff were in the calving barn during the expulsion phase in 100% of cases. On the contrary the cows without the device were assisted only in 17% of cases (P < 0.001).
Genetic relationships between live animal scan traits and carcass traits of Australian Angus bulls and heifers
Authors: Börner Vinzent , Johnston David J. , Graser Hans-Ulrich
Published: April 2013

Genetic parameters of four ultrasound live-scan traits and five carcass traits of Australian Angus cattle were examined with regard to sex and age of the scanned individuals. Live-scans were subdivided according to whether the observation was obtained from a bull or a heifer. In addition, two age subset (‘young’ and ‘old’) within sex were formed by k-means clustering around two centres within sex according to the age at scanning. REML estimates for heritabilities, genetic, residual and phenotypic correlations for each trait and trait combination were derived from a series of uni-, bi- and tri-variate analysis. Statistically significant age effects could be found for heritablities of scan intra-muscular fat content in heifers and scan fat depth at P8 site and scan rib fat depth in bulls, and for genetic correlations between the scan traits fat depth at P8 site, rib fat depth and eye muscle area. However, differences in heritablities between age sets within sex did not exceed 0.05, and genetic correlations between scan traits of ‘young’ and ‘old’ animals were at least 0.9. Differences between genetic correlations of abattoir carcass traits and ‘young’ and ‘old’ live-scan traits, respectively, were not significant due to high standard errors but up to 0.44. The larger of these differences were found for combinations of scan-traits and non-target carcass traits and not for combination of scan-traits and their actual carcass target traits. Thus, although some results suggest an age effect on the genetic parameters of scan traits, the extent of this effect is of limited impact on breeding value accuracy and genetic gain of scan traits. Furthermore, a possible age effect on correlations to economically important carcass traits need to be underpinned by more carcass traits observations in order to get unambiguous results allowing to draw consequences of scanning younger individuals for accuracy of breeding values and genetic gain in carcass traits.
Inhibition of tumor growth and metastasis by a self-therapeutic nanoparticle
Authors: Arvizo Rochelle R. , Saha Sounik , Wang Enfeng , Robertson J. David , Bhattacharya Resham , Mukherjee Priyabrata
Published: April 2013

Although biomedical applications of nanotechnology, which typically involve functionalized nanoparticles, have taken significant strides, biological characterization of unmodified nanoparticles remains underinvestigated. Herein we demonstrate that unmodified gold nanoparticles (AuNPs) inhibit the proliferation of cancer cells in a size- and concentration-dependent manner by abrogating MAPK-signaling. In addition, these AuNPs reverse epithelial-mesenchymal transition (EMT) in cancer cells by reducing secretion of a number of proteins involved in EMT, up-regulating E-Cadherin, and down-regulating Snail, N-Cadherin, and Vimentin. Inhibition of MAPK signaling and reversal of EMT upon AuNP treatment inhibits tumor growth and metastasis in two separate orthotopic models of ovarian cancer. Western blot analyses of tumor tissues reveal up-regulation of E-Cadherin and down-regulation of Snail and phospho-MAPK, confirming the reversal of EMT and inhibition of MAPK signaling upon AuNP treatment. The ability of a single self-therapeutic nanoparticle to abrogate signaling cascades of multiple growth factors is distinctive and purports possible medical applications as potential antitumor and antimetastatic agent.
Sphingosine-1-phosphate-mediated osteoclast precursor monocyte migration is a critical point of control in antibone-resorptive action of active vitamin D
Authors: Kikuta Junichi , Kawamura Shunsuke , Okiji Fumie , Shirazaki Mai , Sakai Sadaoki , Saito Hitoshi , Ishii Masaru
Published: April 2013

The migration and positioning of osteoclast precursor monocytes are controlled by the blood-enriched lipid mediator sphingosine-1-phosphate (S1P) and have recently been shown to be critical points of control in osteoclastogenesis and bone homeostasis. Here, we show that calcitriol, which is the hormonally active form of vitamin D, and its therapeutically used analog, eldecalcitol, inhibit bone resorption by modulating this mechanism. Vitamin D analogs have been used clinically for treating osteoporosis, although the mode of its pharmacologic action remains to be fully elucidated. In this study, we found that active vitamin D reduced the expression of S1PR2, a chemorepulsive receptor for blood S1P, on circulating osteoclast precursor monocytes both in vitro and in vivo. Calcitriol- or eldecalcitol-treated monocytoid RAW264.7 cells, which display osteoclast precursor-like properties, migrated readily to S1P. Concordantly, the mobility of circulating CX3CR1+osteoclast precursor monocytes was significantly increased on systemic administration of active vitamin D. These results show a mechanism for active vitamin D in controlling the migratory behavior of circulating osteoclast precursors, and this action should be conducive to limiting osteoclastic bone resorption in vivo.
Penis size interacts with body shape and height to influence male attractiveness
Authors: Mautz Brian S. , Wong Bob B. M. , Peters Richard A. , Jennions Michael D.
Published: April 2013

Compelling evidence from many animal taxa indicates that male genitalia are often under postcopulatory sexual selection for characteristics that increase a male’s relative fertilization success. There could, however, also be direct precopulatory female mate choice based on male genital traits. Before clothing, the nonretractable human penis would have been conspicuous to potential mates. This observation has generated suggestions that human penis size partly evolved because of female choice. Here we show, based upon female assessment of digitally projected life-size, computer-generated images, that penis size interacts with body shape and height to determine male sexual attractiveness. Positive linear selection was detected for penis size, but the marginal increase in attractiveness eventually declined with greater penis size (i.e., quadratic selection). Penis size had a stronger effect on attractiveness in taller men than in shorter men. There was a similar increase in the positive effect of penis size on attractiveness with a more masculine body shape (i.e., greater shoulder-to-hip ratio). Surprisingly, larger penis size and greater height had almost equivalent positive effects on male attractiveness. Our results support the hypothesis that female mate choice could have driven the evolution of larger penises in humans. More broadly, our results show that precopulatory sexual selection can play a role in the evolution of genital traits.
Zif268
/
egr1
gene controls the selection, maturation and functional integration of adult hippocampal newborn neurons by learning
Authors: Veyrac Alexandra , Gros Alexandra , Bruel-Jungerman Elodie , Rochefort Christelle , Kleine Borgmann Felix B. , Jessberger Sebastian , Laroche Serge
Published: April 2013

New neurons are continuously added to the dentate gyrus of the adult mammalian brain. During the critical period of a few weeks after birth when newborn neurons progressively mature, a restricted fraction is competitively selected to survive in an experience-dependent manner, a condition for their contribution to memory processes. The mechanisms that control critical stages of experience-dependent functional incorporation of adult newborn neurons remain largely unknown. Here, we identify a unique transcriptional regulator of the functional integration of newborn neurons, the inducible immediate early gene
zif268/egr1
. We show that newborn neurons in
zif268
-KO mice undergo accelerated death during the critical period of 2–3 wk around their birth and exhibit deficient neurochemical and morphological maturation, including reduced GluR1 expression, increased NKCC1/KCC2b chloride cotransporter ratio, altered dendritic development, and marked spine growth defect. Investigating responsiveness of newborn neurons to activity-dependent expression of
zif268
in learning, we demonstrate that in the absence of
zif268
, training in a spatial learning task during this critical period fails to recruit newborn neurons and promote their survival, leading to impaired long-term memory. This study reveals a previously unknown mechanism for the control of the selection, functional maturation, and experience-dependent recruitment of dentate gyrus newborn neurons that depends on the inducible immediate early gene
zif268
, processes that are critical for their contribution to hippocampal-dependent long-term memory.
Protein chemical synthesis by serine and threonine ligation
Authors: Zhang Yinfeng , Xu Ci , Lam Hiu Yung , Lee Chi Lung , Li Xuechen
Published: April 2013

An efficient method has been developed for the salicylaldehyde ester-mediated ligation of unprotected peptides at serine (Ser) or threonine (Thr) residues. The utility of this peptide ligation approach has been demonstrated through the convergent syntheses of two therapeutic peptides––ovine-corticoliberin and Forteo––and the human erythrocyte acylphosphatase protein (∼11 kDa). The requisite peptide salicylaldehyde ester precursor is prepared in an epimerization-free manner via Fmoc–solid-phase peptide synthesis.
Warming-induced upslope advance of subalpine forest is severely limited by geomorphic processes
Authors: Macias-Fauria Marc , Johnson Edward A.
Published: April 2013

Forests are expected to expand into alpine areas because of climate warming, causing land-cover change and fragmentation of alpine habitats. However, this expansion will only occur if the present upper treeline is limited by low-growing season temperatures that reduce plant growth. This temperature limitation has not been quantified at a landscape scale. Here, we show that temperature alone cannot realistically explain high-elevation tree cover over a >100-km
2
area in the Canadian Rockies and that geologic/geomorphic processes are fundamental to understanding the heterogeneous landscape distribution of trees. Furthermore, upslope tree advance in a warmer scenario will be severely limited by availability of sites with adequate geomorphic/topographic characteristics. Our results imply that landscape-to-regional scale projections of warming-induced, high-elevation forest advance into alpine areas should not be based solely on temperature-sensitive, site-specific upper-treeline studies but also on geomorphic processes that control tree occurrence at long (centuries/millennia) timescales.
An experimental displacement and over 50 years of tag-recoveries show that monarch butterflies are not true navigators
Authors: Mouritsen Henrik , Derbyshire Rachael , Stalleicken Julia , Mouritsen Ole Ø. , Frost Barrie J. , Norris D. Ryan
Published: April 2013

Monarch butterflies (Danaus plexippus) breeding in eastern North America are famous for their annual fall migration to their overwintering grounds in Mexico. However, the mechanisms they use to successfully reach these sites remain poorly understood. Here, we test whether monarchs are true navigators who can determine their location relative to their final destination using both a “compass” and a “map”. Using flight simulators, we recorded the orientation of wild-caught monarchs in southwestern Ontario and found that individuals generally flew in a southwest direction toward the wintering grounds. When displaced 2,500 km to the west, the same individuals continued to fly in a general southwest direction, suggesting that monarchs use a simple vector-navigation strategy (i.e., use a specific compass bearing without compensating for displacement). Using over 5 decades of field data, we also show that the directional concentration and the angular SD of recoveries from tagged monarchs largely conformed to two mathematical models describing the directional distribution of migrants expected under a vector-navigation strategy. A third analysis of tagged recoveries shows that the increasing directionality of migration from north to south is largely because of the presence of geographic barriers that guide individuals toward overwintering sites. Our work suggests that monarchs breeding in eastern North America likely combine simple orientation mechanisms with geographic features that funnel them toward Mexican overwintering sites, a remarkable achievement considering that these butterflies weigh less than a gram and travel thousands of kilometers to a site they have never seen.
Prochlorococcus
can use the Pro1404 transporter to take up glucose at nanomolar concentrations in the Atlantic Ocean
Authors: Muñoz-Marín María del Carmen , Luque Ignacio , Zubkov Mikhail V. , Hill Polly G. , Diez Jesús , García-Fernández José Manuel
Published: April 2013

Prochlorococcus
is responsible for a significant part of CO
2
fixation in the ocean. Although it was long considered an autotrophic cyanobacterium, the uptake of organic compounds has been reported, assuming they were sources of limited biogenic elements. We have shown in laboratory experiments that
Prochlorococcus
can take up glucose. However, the mechanisms of glucose uptake and its occurrence in the ocean have not been shown. Here, we report that the gene Pro1404 confers capability for glucose uptake in
Prochlorococcus marinus
SS120. We used a cyanobacterium unable to take up glucose to engineer strains that express the Pro1404 gene. These recombinant strains were capable of specific glucose uptake over a wide range of glucose concentrations, showing multiphasic transport kinetics. The
K

s

constant of the high affinity phase was in the nanomolar range, consistent with the average concentration of glucose in the ocean. Furthermore, we were able to observe glucose uptake by
Prochlorococcus
in the central Atlantic Ocean, where glucose concentrations were 0.5–2.7 nM. Our results suggest that
Prochlorococcus
are primary producers capable of tuning their metabolism to energetically benefit from environmental conditions, taking up not only organic compounds with key limiting elements in the ocean, but also molecules devoid of such elements, like glucose.
Structure of the Leanyer orthobunyavirus nucleoprotein–RNA complex reveals unique architecture for RNA encapsidation
Authors: Niu Fengfeng , Shaw Neil , Wang Yao E. , Jiao Lianying , Ding Wei , Li Xiaomin , Zhu Ping , Upur Halmurat , Ouyang Songying , Cheng Genhong , Liu Zhi-Jie
Published: April 2013

Negative-stranded RNA viruses cover their genome with nucleoprotein (N) to protect it from the human innate immune system. Abrogation of the function of N offers a unique opportunity to combat the spread of the viruses. Here, we describe a unique fold of N from Leanyer virus (LEAV,
Orthobunyavirus
genus, Bunyaviridae family) in complex with single-stranded RNA refined to 2.78 Å resolution as well as a 2.68 Å resolution structure of LEAV N–ssDNA complex. LEAV N is made up of an N- and a C-terminal lobe, with the RNA binding site located at the junction of these lobes. The LEAV N tetramer binds a 44-nucleotide-long single-stranded RNA chain. Hence, oligomerization of N is essential for encapsidation of the entire genome and is accomplished by using extensions at the N and C terminus. Molecular details of the oligomerization of N are illustrated in the structure where a circular ring-like tertiary assembly of a tetramer of LEAV N is observed tethering the RNA in a positively charged cavity running along the inner edge. Hydrogen bonds between N and the C2 hydroxyl group of ribose sugar explain the specificity of LEAV N for RNA over DNA. In addition, base-specific hydrogen bonds suggest that some regions of RNA bind N more tightly than others. Hinge movements around F20 and V125 assist in the reversal of capsidation during transcription and replication of the virus. Electron microscopic images of the ribonucleoprotein complexes of LEAV N reveal a filamentous assembly similar to those found in phleboviruses.
Redesign of a cross-reactive antibody to dengue virus with broad-spectrum activity and increased in vivo potency
Authors: Tharakaraman Kannan , Robinson Luke N. , Hatas Andrew , Chen Yi-Ling , Siyue Liu , Raguram S. , Sasisekharan V. , Wogan Gerald N. , Sasisekharan Ram
Published: April 2013

Significance

Dengue virus infects more than 200 million people each year, and incidence of severe disease is increasing with no effective countermeasures. We demonstrate in this paper the engineering of an antibody that binds to all four serotypes of dengue virus with potent activity in vitro and in vivo. We also outline a distinct and widely applicable approach to antibody engineering that provides important information on the paratope/epitope interface in the absence of crystal structure data, enabling identification of antibody amino acids that could be mutated. We demonstrate experimentally the alteration of both specificity (enabling cross-serotype binding) and affinity of the engineered antibody.
Passive Integrated Transponder (PIT) Tracking versus Snorkeling: Quantification of Fright Bias and Comparison of Techniques in Habitat Use Studies
Authors: Ellis Theoren R. , Linnansaari Tommi , Cunjak Richard A.
Published: April 2013

Quantitative assessment of day and night fright bias (i.e., flight response) of Atlantic Salmon Salmo salar parr during passive integrated transponder (PIT) tracking surveys was carried out during summer (water temperature, 18–22°C) and autumn (water temperature, <3°C). In addition, PIT‐tracking and snorkeling survey methods were compared to assess whether the two methods result in similar habitat use data for Atlantic Salmon parr at the same study site. During summer fright bias surveys, 0–15% of parr displayed a flight response to PIT‐tracking techniques in the riffle–run–pool habitat types commonly used by Atlantic Salmon parr; 24–25% displayed a flight response in relatively unused, shallow, calm water habitats. No flight responses were observed in autumn surveys with colder water temperatures in any habitat type. Larger numbers of salmon parr were observed using PIT tracking regardless of stream discharge. Furthermore, significant differences in habitat use frequency curves between these two methods were observed due largely to higher Atlantic Salmon parr abundances being detected by PIT tracking in shallow water depths at lower discharges and the ability to detect inactive salmon parr hiding within the substrate. PIT tracking was found to be a valid method for habitat assessment and provides more reliable habitat use data than traditional snorkeling methods in small streams.
Development of a Sperm Cryopreservation Protocol for Redside Dace: Implications for Genome Resource Banking
Authors: Butts Ian A. E. , Mokdad Ali , Trippel Edward A. , Pitcher Trevor E.
Published: April 2013

Populations of Redside DaceClinostomus elongatushave declined in many areas across the species’ North American range. Therefore, the development of sperm cryopreservation technology would provide an invaluable means of preserving genetic diversity in populations that are in imminent danger of extirpation. We developed cryopreservation protocols by testing the effects of diluent (buffered sperm motility‐inhibiting saline solution [BSMIS]; BSMIS + glycine; sucrose; and Hanks’ balanced salt solution [HBSS]), cryoprotectant (dimethyl sulfoxide [DMSO]; propylene glycol [PG]; N,N‐dimethylacetamide [DMA]; and methanol), freezing rate (1, 5, and 10°C/min), and male‐to‐male variation on sperm quality. Incubating sperm in extenders affected motility; BSMIS + glycine + methanol, BSMIS + glycine + PG, and HBSS + methanol were the only treatments for which motility was not significantly different from that of fresh sperm. Sperm frozen with sucrose had higher motility than sperm frozen with BSMIS + glycine, and sperm frozen with DMSO had higher motility than sperm frozen with methanol. Freezing rates were evaluated for BSMIS + glycine, HBSS, and sucrose; all diluents were frozen with DMSO. The effect of freezing rate was not significant for BSMIS + glycine or for HBSS, but an effect was detected for sucrose, with sperm frozen at 5°C/min or 10°C/min having higher motility than sperm frozen at 1°C/min. The effect of extender was not significant at 1°C/min or 5°C/min, but an effect was detected at 10°C/min such that sperm frozen with sucrose had the highest motility. Male‐to‐male variability was evaluated by using sucrose + DMSO and a freezing rate of 10°C/min. For these males, the sperm motility recovery index ranged from 6.67% to 79.27%, and the sperm velocity recovery index ranged from 21.37% to 57.33%. Our findings demonstrate that cryopreservation of Redside Dace sperm in a sucrose + DMSO extender at a freezing rate of 10°C/min is adequate for preserving genetic diversity via sperm banks.