bluuebunny/crossref_metadata_2025 huggingface dataset:
L’impact de la scolarisation post-secondaire sur les représentations sociales des jeunes Québécois
Authors: Bernier Léon
Published: July 2012

Par une approche longitudinale utilisant une technique d’analyse multivariée, l’étude vise à spécifier l’impact du milieu collégial québécois sur les représentations sociales des jeunes. Incluant deux variables d’appartenance sociale, le sexe et le statut socio-économique d’origine, la démarche adoptée se dédouble pour comparer d’une part les jeunes qui ont quitté le système scolaire après la fin du secondaire à ceux qui ont poursuivi leurs études collégiales, et d’autre part les étudiants du secteur collégial professionnel à ceux du secteur général. Les résultats démontrent qu’à ces trois cheminements scolaires correspondent des univers d’attitudes distincts, que la distanciation est déjà instaurée avant la fin des études secondaires, et que le passage par le milieu collégial vient surtout renforcer et clarifier des différences résultant d’étapes antérieures dans le processus de socialisation. Un concept interprétatif est introduit, celui de réseau culturel.
Recherches linguistiques appliquées à l’enseignement du français langue maternelle en Ontario
Authors: Mougeon Raymond , Beniak Édouard
Published: July 2012

Nous présentons les résultats principaux d’une série de recherches linguistiques sur le français d’élèves franco-ontariens. Ensuite, dans le détail, nous décrivons les principes et la nature du matériel pédagogique destiné à l’enseignement du français langue maternelle en Ontario dont ces recherches permettent l’élaboration. Nous terminons par un examen des rôles respectifs que peuvent et doivent jouer les enseignants et la société pour d’une part augmenter l’efficacité du matériel pédagogique et d’autre part assurer le maintien du français chez les jeunes Franco-ontariens.
La formation pratique dans la formation initiale des enseignants
Authors: Caisse Maurice
Published: July 2012

Dans le cadre de la formation de base des maîtres, cet article propose une définition de la formation pratique à partir de trois éléments majeurs : la participation de l’étudiant-maître à des activités de formation pratique, la supervision et l’identification des objectifs. L’auteur classe ensuite les activités de formation pratique en fonction des milieux où elles se déroulent; il précise la place et l’importance qu’on devrait accorder à la formation pratique au sein de la formation initiale des enseignants et en identifie les responsables. Il suggère enfin de confier, dans l’Université, la responsabilité des activités de formation pratique en éducation et le développement de la recherche dans ce champ à une structure à laquelle des professeurs seraient rattachés.
Une contribution à un cadre théorique sur l’insertion professionnelle des jeunes
Authors: Laflamme Claude
Published: July 2012

Après avoir présenté quelques facteurs qui influencent l’insertion professionnelle des jeunes travailleurs, nous examinons quelques théories économiques (capital humain, quête d’emploi, double marché du travail) qui nous éclairent sur cette situation d’insertion professionnelle. L’examen critique de ces facteurs et de ces théories permet, dans une certaine mesure, de montrer la complexité de la situation et d’inciter à adopter une approche sociologique de l’insertion professionnelle. À ce titre, les facteurs d’insertion professionnelle sont interprétés comme des faits de socialisation quand ils relèvent du système d’enseignement et comme des faits d’organisation quand ils font rapport au marché du travail.
Le caractère masculin de l’éducation
Authors: Solar Claudie
Published: July 2012

La lecture de l’éducation qui est proposée dans cet article tend à faire ressortir son caractère masculin; c’est-à-dire que celle-ci, dans sa structure, son mode de fonctionnement, ses programmes, ses contenus et ses fondements, a été pensée par et pour les hommes. L’argumentation se fonde sur une analyse de l’éducation des filles francophones au Québec.
La contribution des manuels de sciences à l’acquisition d’une culture scientifique
Authors: Souque Jean-Pascal
Published: July 2012

Le présent article porte sur les représentations de la science véhiculées par le système scolaire et sur le rôle que peuvent jouer les manuels de sciences dans la construction de ces représentations. Deux dimensions de ces représentations sont examinées : la nature de la science et l’histoire des sciences. Constatant le manque de recherches à ce propos, l’article montre le potentiel de certaines méthodologies qualitatives, comme l’analyse philosophique, pour y rémédier.
L’apprentissage adulte : la phase de la maturité
Authors: Gagnon Rodolphe
Published: July 2012

Ce texte porte sur la nature de l’apprentissage de l’individu d’âge mûr. Après l’exploration des phases du développement de l’adulte et leur mise en rapport avec l’apprentissage, on présente et analyse un programme professionnel — le HOS du Fielding Institute — qui s’appuie sur une théorie de l’apprentissage appropriée au mitan de la vie.
Subcellular localization of adenylate kinases in Plasmodium falciparum
Authors: Ma Jipeng , Rahlfs Stefan , Jortzik Esther , Heiner Schirmer R. , Przyborski Jude M. , Becker Katja
Published: July 2012

PfAK2
and
SERP
colocalize by fluorescence microscopy (View interaction)
Assessment of endometrial volume and vascularization using transvaginal 3D power Doppler angiography in women with postmenopausal bleeding
Authors: Rossi Alberto , Forzano Leonardo , Romanello Irene , Fachechi Giorgio , Marchesoni Diego
Published: July 2012

Objective

To compare the usefulness of 3D power Doppler angiography (3D‐PDA) and endometrial thickness measurement by 2D Doppler ultrasound in the distinction of benign from malignant disease in postmenopausal women with abnormal uterine bleeding (AUB) and an endometrial thickness greater than 4.5 mm.

Methods

Forty‐eight women with AUB and an endometrial thickness greater than 4.5 mm on 2D ultrasound underwent 3D‐PDA. The endometrium and a 5‐mm subendometrial “shell” were evaluated at rotation angles of 9° and 30°. Endometrial volume, vascularity index, flow index, and vascularization flow index were obtained.

Results

The histologic findings were normal or benign for 38 women (79%) and malignant for 10 (21%). All vascular indices were significantly higher in the group with malignancies except for the vascularization flow index. There were no differences in the values obtained using the 9° or the 30° angle. Receiver‐operating characteristics curves were traced for all indices. The vascularity index had the best area under the curve (0.78), 77.8% sensitivity, and 82.6% specificity. The areas under the curve were smaller for the shell than for the endometrium.

Conclusion

3D‐PDA was not found better than 2D ultrasound at distinguishing benign from malignant disease in women with AUB and an endometrial thickness greater than 4.5 mm.
Finite-sample-size effects on convection in mushy layers
Authors: Zhong J.-Q. , Fragoso A. T. , Wells A. J. , Wettlaufer J. S.
Published: July 2012

We report theoretical and experimental investigations of the flow instability responsible for mushy-layer convection with chimneys, drainage channels devoid of solid, during steady-state solidification of aqueous ammonium chloride. Under certain growth conditions a state of steady mushy-layer growth with no flow is unstable to the onset of convection, resulting in the formation of chimneys. We present regime diagrams to quantify the state of the flow as a function of the initial liquid concentration, the porous-medium Rayleigh number, and the sample width. For a given liquid concentration, increasing both the porous-medium Rayleigh number and the sample width drove a transition from a weakly convecting chimney free state to a state of mushy-layer convection with fully developed chimneys. Increasing the concentration ratio stabilized the system and suppressed the formation of chimneys. As the initial liquid concentration increased, onset of convection and formation of chimneys occurred at larger values of the porous-medium Rayleigh number, but the critical cell widths for chimney formation are far less sensitive to the liquid concentration. At the highest liquid concentration, the mushy-layer mode of convection did not occur in the experiment. The formation of multiple chimneys and the morphological transitions between these states are discussed. The experimental results are interpreted in terms of a previous theoretical analysis of finite amplitude convection with chimneys, with a single value of the mushy-layer permeability consistent with the liquid concentrations considered in this study.
Turbulent–laminar coexistence in wall flows with Coriolis, buoyancy or Lorentz forces
Authors: Brethouwer G. , Duguet Y. , Schlatter P.
Published: July 2012

Direct numerical simulations of subcritical rotating, stratified and magneto-hydrodynamic wall-bounded flows are performed in large computational domains, focusing on parameters where laminar and turbulent flow can stably coexist. In most cases, a regime of large-scale oblique laminar-turbulent patterns is identified at the onset of transition, as in the case of pure shear flows. The current study indicates that this oblique regime can be shifted up to large values of the Reynolds number$\mathit{Re}$by increasing the damping by the Coriolis, buoyancy or Lorentz force. We show evidence for this phenomenon in three distinct flow cases: plane Couette flow with spanwise cyclonic rotation, plane magnetohydrodynamic channel flow with a spanwise or wall-normal magnetic field, and open channel flow under stable stratification. Near-wall turbulence structures inside the turbulent patterns are invariably found to scale in terms of viscous wall units as in the fully turbulent case, while the patterns themselves remain large-scale with a trend towards shorter wavelength for increasing$\mathit{Re}$. Two distinct regimes are identified: at low Reynolds numbers the patterns extend from one wall to the other, while at large Reynolds number they are confined to the near-wall regions and the patterns on both channel sides are uncorrelated, the core of the flow being highly turbulent without any dominant large-scale structure.
Spatial optimal growth in three-dimensional compressible boundary layers
Authors: Tempelmann David , Hanifi Ardeshir , Henningson Dan S.
Published: July 2012

This paper represents a continuation of the work by Tempelmann et al. (J. Fluid Mech., vol. 646, 2010b, pp. 5–37) on spatial optimal growth in incompressible boundary layers over swept flat plates. We present an extension of the methodology to compressible flow. Also, we account for curvature effects. Spatial optimal growth is studied for boundary layers over both flat and curved swept plates with adiabatic and cooled walls. We find that optimal growth increases for higher Mach numbers. In general, extensive non-modal growth is observed for all boundary layer cases even in subcritical regions, i.e. where the flow is stable with respect to modal crossflow disturbances. Wall cooling, despite stabilizing crossflow modes, destabilizes disturbances of non-modal nature. Curvature acts similarly on modal as well as non-modal disturbances. Convex walls have a stabilizing effect on the boundary layer whereas concave walls have a destabilizing effect. The physical mechanisms of optimal growth in all studied boundary layers are found to be similar to those identified for incompressible flat-plate boundary layers.
Perturbation response and pinch-off of vortex rings and dipoles
Authors: O’Farrell Clara , Dabiri John O.
Published: July 2012

The nonlinear perturbation response of two families of vortices, the Norbury family of axisymmetric vortex rings and the Pierrehumbert family of two-dimensional vortex pairs, is considered. Members of both families are subjected to prolate shape perturbations similar to those previously introduced to Hill’s spherical vortex, and their response is computed using contour dynamics algorithms. The response of the entire Norbury family to this class of perturbations is considered, in order to bridge the gap between past observations of the behaviour of thin-cored members of the family and that of Hill’s spherical vortex. The behaviour of the Norbury family is contrasted with the response of the analogous two-dimensional family of Pierrehumbert vortex pairs. It is found that the Norbury family exhibits a change in perturbation response as members of the family with progressively thicker cores are considered. Thin-cored vortices are found to undergo quasi-periodic deformations of the core shape, but detrain no circulation into their wake. In contrast, thicker-cored Norbury vortices are found to detrain excess rotational fluid into a trailing vortex tail. This behaviour is found to be in agreement with previous results for Hill’s spherical vortex, as well as with observations of pinch-off of experimentally generated vortex rings at long formation times. In contrast, the detrainment of circulation that is characteristic of pinch-off is not observed for Pierrehumbert vortex pairs of any core size. These observations are in agreement with recent studies that contrast the formation of vortices in two and three dimensions. We hypothesize that transitions in vortex formation, such as those occurring between wake shedding modes and in vortex pinch-off more generally, might be understood and possibly predicted based on the observed perturbation responses of forming vortex rings or dipoles.
Using surfactants to stabilize two-phase pipe flows of core–annular type
Authors: Bassom Andrew P. , Blyth M. G. , Papageorgiou D. T.
Published: July 2012

The stability of a core–annular fluid arrangement consisting of two concentric fluid layers surrounding a solid cylindrical rod on the axis of a circular pipe is examined when the interface between the two fluid layers is covered with an insoluble surfactant. The motion is driven either by an imposed axial pressure gradient or by the movement of the rod at a prescribed constant velocity. In the basic state the fluid motion is unidirectional and the interface between the two fluids is cylindrical. A linear stability analysis is performed for arbitrary layer thicknesses and arbitrary Reynolds number. The results show that the flow can be fully stabilized, even at zero Reynolds number, if the base flow shear rate at the interface is set appropriately. This result is confirmed by an asymptotic analysis valid when either of the two fluid layers is thin in comparison to the gap between the pipe wall and the rod. It is found that for a thin inner layer the flow can be stabilized if the inner fluid is more viscous than the outer fluid, and the opposite holds true for a thin outer layer. It is also demonstrated that traditional core–annular flow, for which the rod is absent, may be stabilized at zero Reynolds number if the annular layer is sufficiently thin. Finally, weakly nonlinear simulations of a coupled set of partial differential evolution equations for the interface position and surfactant concentration are conducted with the rod present in the limit of a thin inner layer or a thin outer layer. The ensuing dynamics are found to be sensitive to the size of the curvature of the undisturbed interface.
Maximum likelihood estimation of individual inbreeding coefficients and null allele frequencies
Authors: HALL NATHAN , MERCER LAINA , PHILLIPS DAISY , SHAW JONATHAN , ANDERSON AMY D.
Published: July 2012

In this paper, we developed and compared several expectation–maximization (EM) algorithms to find maximum likelihood estimates of individual inbreeding coefficients using molecular marker information. The first method estimates the inbreeding coefficient for a single individual and assumes that allele frequencies are known without error. The second method jointly estimates inbreeding coefficients and allele frequencies for a set of individuals that have been genotyped at several loci. The third method generalizes the second method to include the case in which null alleles may be present. In particular, it is able to jointly estimate individual inbreeding coefficients and allele frequencies, including the frequencies of null alleles, and accounts for missing data. We compared our methods with several other estimation procedures using simulated data and found that our methods perform well. The maximum likelihood estimators consistently gave among the lowest root-mean-square-error (RMSE) of all the estimators that were compared. Our estimator that accounts for null alleles performed particularly well and was able to tease apart the effects of null alleles, randomly missing genotypes and differing degrees of inbreeding among members of the datasets we analysed. To illustrate the performance of our estimators, we analysed previously published datasets on mice (Mus musculus) and white-tailed deer (Odocoileus virginianus).
Sequential cohort study comparing chlorine dioxide wipes with automated washing for decontamination of flexible nasendoscopes
Authors: Phua C Q , Mahalingappa Y , Karagama Y
Published: July 2012

Introduction:

Flexible nasoendoscope is an important tool in otorhinolaryngology practice. The endoscope needs to be decontaminated prior to use in the next patient. The 2005 ENT-UK guidance for cleaning fibre-optic laryngoscopes stated that the ideal disinfecting agent and process should be effective and have low capital and maintenance costs.

Objective:

To compare the efficacy and cost-effectiveness of chlorine dioxide wipes versus automated washer, for decontamination of flexible nasendoscopes.

Methods:

A sequential cohort,in vitrostudy was performed to test the efficacy of chlorine dioxide wipes and automated washer. Costs were also calculated.

Results:

After deliberate bacterial contamination of the nasendoscope and subsequent decontamination, swab samples from the endoscope showedStaphylococcus epidermidisgrowth in 2 per cent (1/50 swabs) of the chlorine dioxide wipe group and in 28 per cent (14/50 swabs) of the automated washer group (p = 0.00). Based on a projected 10-year cost calculation, the automated washer was cheaper.

Conclusion:

Further studies are required to test whether these results are replicable. A similar study should be performed using real patients, to check the significance of improper decontamination.
Traumatic tympanic membrane perforation by a needlefish: case report
Authors: Bijoor P , Rourke T , Thomson H
Published: July 2012

Objectives:

We report a unique case of traumatic tympanic membrane perforation caused by a needlefish beak. We describe the mechanism of injury, the clinical findings and the treatment.

Case report:

An 11-year-old boy presented with otorrhoea and hearing loss secondary to a traumatic tympanic membrane perforation by a needlefish. The perforation was repaired by performing a myringoplasty, with satisfactory post-operative audiological results.

Conclusion:

To our knowledge, this is the first reported case of its kind. It is recommended that careful examination of the middle-ear space should always be carried out prior to and during myringoplasty if there is a possibility of a foreign body.
Hoarseness secondary to haemodialysis: case report and literature review
Authors: Santhirakumar M , Phua C Q , Karagama Y
Published: July 2012

Introduction:

Hoarseness is common and can have a major impact on patients’ quality of life. We report a rare case of hoarseness secondary to haemodialysis.

Case report:

A 62-year-old man described developing transient hoarseness after haemodialysis sessions, which he underwent three times weekly. Fibre-optic nasendoscopy showed incomplete glottis closure due to bowing of the vocal folds. A computed tomography scan of the neck and thorax was unremarkable. Speech therapy was unhelpful. The renal physicians concluded that no change could be made to his dialysis regime. The patient subsequently underwent injection laryngoplasty with calcium hydroxylapatite, with marked improvement of his symptoms.

Discussion:

A literature search found one relevant article reporting that 60 per cent of patients suffered post-dialysis hoarseness and decreased vocal fold thickness. It is postulated that dialysis causes dehydration of Reinke's space, affecting vocal fold thickness and the patient's voice.

Conclusion:

Hoarseness caused by haemodialysis is uncharted territory. Further research is required to determine its prevalence and contributing factors.
Differential diagnosis of recurrent or bilateral peripheral facial palsy
Authors: Oosterveer D M , Bénit C P , de Schryver E L L M
Published: July 2012

Objective:

To describe the differential diagnosis of recurrent or bilateral peripheral facial palsy.

Method:

Case report and literature review.

Results:

Two patients with recurrent, alternating, peripheral facial palsy are described. In both patients, additional investigation was performed to search for a specific diagnosis. In the first patient, only a positive family history was found, indicating a possible familial susceptibility. In the other patient, diabetes mellitus and hypertension were identified as risk factors.

Conclusion:

There is an important and extensive differential diagnosis of recurrent or bilateral facial palsy. However, in a large proportion of patients the cause remains unknown.
Rapidly progressing giant invasive prolactinoma
Authors: Care R H , Sunkaraneni V S , Theaker J , Harries P G
Published: July 2012

Objective:

We report an extremely rare case of a giant invasive prolactinoma presenting as a nasopharyngeal tumour.

Method:

Case report and literature review regarding giant prolactinoma.

Results:

Giant prolactinoma is a rare form of prolactinoma which accounts for 0.5–4.4 per cent of all pituitary tumours. It is more common in men and generally presents with symptoms of endocrine disturbance or neurological deficit.

Conclusion:

To our knowledge, this is the first report of giant prolactinoma presenting with symptoms of sinusitis and nasopharyngeal tumour.
Diagnosis and treatment of depression following routine screening in patients with coronary heart disease or diabetes: a database cohort study
Authors: Burton C. , Simpson C. , Anderson N.
Published: July 2012

Background

Depression is common in chronic illness and screening for depression has been widely recommended. There have been no large studies of screening for depression in routine care for patients with chronic illness.

Method

We performed a retrospective cohort study to examine the timing of new depression diagnosis or treatment in relation to annual screening for depression in patients with coronary heart disease (CHD) or diabetes. We examined a database derived from 1.3 million patients registered with general practices in Scotland for the year commencing 1 April 2007. Eligible patients had either CHD or diabetes, were screened for depression during the year and either received a new diagnosis of depression or commenced a new course of antidepressant (excluding those commonly used to treat diabetic neuropathy). Analysis was by the self-controlled case-series method with the outcome measure being the relative incidence (RI) in the period 1–28 days after screening compared to other times.

Results

A total of 67358 patients were screened for depression and 2269 received a new diagnosis or commenced treatment. For the period after screening, the RI was 3.03 [95% confidence interval (CI) 2.44–3.78] for diagnosis and 1.78 (95% CI 1.54–2.05) for treatment. The number needed to screen was 976 (95% CI 886–1104) for a new diagnosis and 687 (95% CI 586–853) for new antidepressant treatment.

Conclusions

Systematic screening for depression in patients with chronic disease in primary care results in a significant but small increase in new diagnosis and treatment in the following 4 weeks.
Heterogeneity in fishers' and managers' preferences towards management restrictions and benefits in Kenya
Authors: MCCLANAHAN TIMOTHY R. , ABUNGE CAROLINE A. , CINNER JOSHUA E.
Published: July 2012

Increasing the chances that resource users engage in and comply with management regulations is a continual problem for many conservation initiatives globally. This is particularly common when resource users perceive more personal costs than benefits from specific management actions. Analysis of interviews with managers and fishers from 22 landing sites along the coast of Kenya indicated how key stakeholders perceived the scale of benefits and costs from different management strategies. Potential underlying causes of divergent perceptions towards different management tools were evaluated, including marine protected areas, no-take fisheries closures, gear use, minimum size of fish caught and species restrictions. The analysis identified three distinct opinion groups: (1) a group of nine landing sites that scaled their preference for most management restrictions neutral to low, with exceptions for minimum sizes of captured fish and gear restrictions; (2) a group of eight landing sites that scaled their preference for the above and species restrictions and closed season higher, and were more neutral about closures and marine protected areas; and (3) a group containing four landing sites and the managers’ offices that rated their preference for the above and closed areas and marine protected areas as high. Logistic regression was used to examine whether these groups differed in wealth, education, age, perceptions of disparity in benefits, dependence on fishing and distance to government marine protected areas. The most frequent significant factor was the resource users’ perceived disparity between the benefits of the management to themselves and their communities, with the benefits to the government. Consequently, efforts to reduce this real or perceived disparity are likely to increase adoption and compliance rates. Most widespread positively-viewed restrictions, such as gear use and minimum size of fish, should be promoted at the national level while other restrictions may be more appropriately implemented at the community level.
One-Year Follow-up of Non-institutionalized Dependent Older Adults: Mortality, Hospitalization, and Mobility
Authors: Sarria Cabrera Marcos Aparecido , Gomes Dellaroza Mara Solange , Trelha Celita Salmaso , Cecilio Celso Henrique , Souza Sara Ellias de
Published: July 2012

Les aînés dépendants qui ne sont pas institutionnalisées présentent une forte morbidité et mortalité, exigent des soins de leurs familles et consomment de ressources primaires de soins de santé. Pour élargir les connaissances en ce qui concerne ce groupe, nous avons effectué une étude prospective d’un an, basée sur la population de cohorte de 130 personnes âgées dépendantes et non-institutionnalisées (60 ans et plus). Cette étude a été stratifiée en fonction du degré de la mobilité: la marche indépendante (groupe A), l’utilisation des aides pour la marche (groupe B), et alité ou confiné au fauteuil roulant (groupe C). Les résultats analysés étaient les suivants: la mort, l’hospitalisation, et l’incapacité de se déplacer. La mortalité totale était au pourcentage de 8.5 (p = 0,05). Le taux global d’hospitalisation était au pourcentage de 34,6, les principales causes étant l’AVC et la pneumonie. La mortalité totale était de 8,5 pour cent (p = 0,05). Le taux global d’hospitalisation était de 34,6 pour cent, les principales causes étant l’AVC et la pneumonie. À la fin d’un an, la proportion de sujets classés comme capables de marcher d’une façon indépendante a baissé (57% contre 43%, p = 0,03). Nous pourrions déduire qu’il y avait un taux élevé de mortalité et d’hospitalisation dans ce groupe de personnes âgées dépendantes, et une proportion croissante de gens handicapés après un an.
Note on the Smallest Root of the Independence Polynomial
Authors: CSIKVÁRI PÉTER
Published: July 2012

One can define the independence polynomial of a graph G as follows. Let ik(G) denote the number of independent sets of size k of G, where i0(G)=1. Then the independence polynomial of G is I(G,x)=∑k=0n(−1)kik(G)xk. In this paper we give a new proof of the fact that the root of I(G,x) having the smallest modulus is unique and is real.
Sperm motility initiation by egg jelly of the anuran,Discoglossus pictusmay be mediated by sperm motility-initiating substance of the internally-fertilizing newt,Cynops pyrrhogaster
Authors: Takayama-Watanabe Eriko , Campanella Chiara , Kubo Hideo , Watanabe Akihiko
Published: July 2012

The egg jelly ofDiscoglossus pictuscontains sperm motility-activating activity, the molecular basis of which has not been studied.Discoglossus pictussperm initiated motility immediately after immersion in egg-jelly extract, as well as after immersion in hyposmotic solution, which initiates sperm motility in the external fertilization of anuran amphibians. Sequential treatment of theD. pictussperm with these two solutions revealed the predominant effect of hyposmolality in initiation of motility. The motility initiation induced by jelly extract was suppressed by a monoclonal antibody (mAb) that is specific for the 34 kDa sperm motility-initiating substance (SMIS) in the egg jelly of the newt,Cynops pyrrhogaster.Immunoblotting using the anti-SMIS mAb revealed several antigenic proteins that included major ones with sizes of 18- and 34-kDa inD. pictusjelly extract. Scanning electron microscopic observation revealed that granules of jelly matrix, in which SMIS localizes and which have a critical role in the internal fertilization ofC. pyrrhogaster, were not observed near the surface of theD. pictusegg jelly. These results suggest that sperm motility-activating activity in egg jelly ofD. pictusmay be mediated by SMIS homologous proteins that act through a mechanism that is partially different from that ofC. pyrrhogaster.
Time Trek: a 13.7 km long nature trail leading through the history of the Universe and the Earth
Authors: Lehto Kirsi , Lehto Harry J. , Brozinski Ari , Gardner Esko , Eklund Olav , Rajala Kirsi , Räsänen Matti , Sääksjärvi Ilari , Vainio Laura , Vuorisalo Timo
Published: July 2012

With the aim to visualize the span of time since the formation of our Universe we have set up a nature and hiking trail called ‘Time Trek’. The 13.7 km length of the trail corresponds to the age of the Universe, and portrays its history including events important for Earth and life. One kilometre corresponds to a billion years, and one metre to a million years of time. The trek combines astronomical, physical, geological and biological time lines, and presents a holistic view of the history of time. It helps people to comprehend the causal and temporal connections of different phenomena. To the trekker, it offers a concrete experience of the lengths and proportions of different time periods, which otherwise are very difficult to understand.
A Novel Population of α-Smooth Muscle Actin-Positive Cells Activated in a Rat Model of Stroke: An Analysis of the Spatio-Temporal Distribution in Response to Ischemia
Authors: Sharma Varun , Ling Tina W , Rewell Sarah S , Hare David L , Howells David W , Kourakis Angela , Wookey Peter J
Published: July 2012

In a rat model of stroke, the spatio-temporal distribution of α-smooth muscle actin-positive, (αSMA+) cells was investigated in the infarcted hemisphere (ipsilateral) and compared with the contralateral hemisphere. At day 3 postischemia, αSMA+ cells were concentrated in two main loci within the ipsilateral hemisphere (Area A) in the medial corpus callosum and (Area B) midway through the striatum adjacent to the lateral ventricle. By day 7 and further by day 14, fewer αSMA+ cells remained in Areas A and B but a steady increase in the peri-infarct was observed. αSMA+ cells also expressed glial acidic fibrillary protein [GFAP: αSMA+/GFAP+ (29%); αSMA+/GFAP– (71%) phenotypes] and feline leukemia virus C receptor 2 (FLVCR2), but not ED1(microglia) and established markers of pericytes normally located in vascular wall. αSMA+ cells were also located close to the subventricular zones (SVZ) adjacent to Areas A and B. In conclusion, αSMA + cells have been identified in a spatial and temporal sequence from the SVZ, at intermediate loci and in the vicinity of the peri-infarct. It is hypothesized that novel populations of αSMA+ precursors of pericytes are born on the SVZ, migrate into the peri-infarct region and are incorporated into new vessels of the peri-infarct regions.
Spectral analysis of x-ray emission created by intense laser irradiation of copper materials
Authors: Huntington C. M. , Kuranz C. C. , Malamud G. , Drake R. P. , Park H.-S. , Maddox B. R.
Published: July 2012

We have measured the x-ray emission, primarily from Kα,Kβ, and Heα lines, of elemental copper foil and “foam” targets irradiated with a mid-1016 W/cm2 laser pulse. The copper foam at 0.1 times solid density is observed to produce 50% greater Heα line emission than copper foil, and the measured signal is well-fit by a sum of three synthetic spectra generated by the atomic physics code FLYCHK. Additionally, spectra from both targets reveal characteristic inner shell Kα transitions from hot electron interaction with the bulk copper. However, only the larger-volume foam target produced significant Kβ radiation, confirming a lower bulk temperature in the higher volume sample.
Wettability of pristine and alkyl-functionalized graphane
Authors: Vanzo Davide , Bratko Dusan , Luzar Alenka
Published: July 2012

Graphane is a hydrogenated form of graphene with high bandgap and planar structure insensitive to a broad range of chemical substitutions. We describe an atomistic simulation approach to predict wetting properties of this new material. We determine the contact angle to be 73°. The lower hydrophobicity compared to graphene is explained by the increased planar density of carbon atoms while we demonstrate that the presence of partial charges on carbon and hydrogen atoms plays only a minor role. We further examine the effects of graphane functionalization by alkyl groups of increasing chain lengths. The gradual increase in contact angle with chain length offers a precise control of surface wettability. A saturated contact angle of 114° is reached in butylated form. We find the saturation of contact angle with respect to the length of the functional groups to coincide with the loss of water's ability to penetrate the n-alkyl molecular brush and interact with carbon atoms of the underlying lattice. Since no experimental data have yet become available, our modeling results provide the first estimate of the wettability of graphane. The results also show how its alkyl functionalization provides the basis for a variety of chemical modifications to tune hydrophilicity while preserving the planar geometry of the substrate.
Efficient method to include nuclear quantum effects in the determination of phase boundaries
Authors: Brito B. G. A. , Antonelli A.
Published: July 2012

We developed a methodology to assess nuclear quantum effects in phase boundaries calculations that is based on the dynamical integration of Clausius-Clapeyron equation using path integral simulations. The technique employs non-equilibrium simulations that are very efficient. The approach was applied to the calculation of the melting line of Ne in an interval of pressures ranging from 1 to 3366 bar. Our results show a very good agreement with both experimental findings and results from previous calculations. The methodology can be applied to solid and liquid phases, without limitations regarding anharmonicities. The method allows the computation of coexistence lines for wide intervals of pressure and temperature using, in principle, a single simulation.
Free energy decomposition analysis of bonding and nonbonding interactions in solution
Authors: Su Peifeng , Liu Hui , Wu Wei
Published: July 2012

A free energy decomposition analysis algorithm for bonding and nonbonding interactions in various solvated environments, named energy decomposition analysis–polarizable continuum model (EDA-PCM), is implemented based on the localized molecular orbital-energy decomposition analysis (LMO-EDA) method, which is recently developed for interaction analysis in gas phase [P. F. Su and H. Li, J. Chem. Phys. 130, 074109 (2009)]10.1063/1.3077917. For single determinant wave functions, the EDA-PCM method divides the interaction energy into electrostatic, exchange, repulsion, polarization, desolvation, and dispersion terms. In the EDA-PCM scheme, the homogeneous solvated environment can be treated by the integral equation formulation of PCM (IEFPCM) or conductor-like polarizable continuum model (CPCM) method, while the heterogeneous solvated environment is handled by the Het-CPCM method. The EDA-PCM is able to obtain physically meaningful interaction analysis in different dielectric environments along the whole potential energy surfaces. Test calculations by MP2 and DFT functionals with homogeneous and heterogeneous solvation, involving hydrogen bonding, vdW interaction, metal-ligand binding, cation-π, and ionic interaction, show the robustness and adaptability of the EDA-PCM method. The computational results stress the importance of solvation effects to the intermolecular interactions in solvated environments.
Nonadiabatic dynamics in open quantum-classical systems: Forward-backward trajectory solution
Authors: Hsieh Chang-Yu , Kapral Raymond
Published: July 2012

A new approximate solution to the quantum-classical Liouville equation is derived starting from the formal solution of this equation in forward-backward form. The time evolution of a mixed quantum-classical system described by this equation is obtained in a coherent state basis using the mapping representation, which expresses N quantum degrees of freedom in a 2N-dimensional phase space. The solution yields a simple dynamics in which a set of N coherent state coordinates evolves in forward and backward trajectories, while the bath coordinates evolve under the influence of the mean potential that depends on these forward and backward trajectories. It is shown that the solution satisfies the differential form of the quantum-classical Liouville equation exactly. Relations to other mixed quantum-classical and semi-classical schemes are discussed.
Study of nitrogen incorporation into GaInNAs: The role of growth temperature in molecular beam epitaxy
Authors: Korpijärvi V.-M. , Aho A. , Laukkanen P. , Tukiainen A. , Laakso A. , Tuominen M. , Guina M.
Published: July 2012

GaInNAs has an important impact on developing GaAs-based optoelectronics and multijunction solar cells, but the complex nature of the nitrogen incorporation into GaInAs is still not fully understood. By combining x-ray diffraction, photoluminescence, reflection high-energy electron diffraction, and photoelectron spectroscopy measurements, we show that nitrogen incorporation is enhanced with increasing growth temperature in the range of 300–450 °C. We study the growth front and show that the surface reconstruction is (1 × 3) regardless of growth temperature in this range. The enhanced nitrogen incorporation can be modeled as a thermally activated process with activation energy of about 0.1 eV.
Correlation of structure and dielectric properties of silver selenomolybdate glasses
Authors: Deb B. , Ghosh A.
Published: July 2012

Structure and dielectric properties of the glasses of compositions yAg2O-(1-y)(xSeO2-(1-x)MoO3) with varying modifier oxide and glass formers ratio have been reported in this paper. Fourier transform infrared (FTIR) spectroscopy has been employed to investigate the effect of SeO2 content on the glass network structure. The existence of different characteristic absorption bands corresponding to the vibration of SeO32− anions, isolated MoO6 units and crystalline molybdate octahedra, has been ascertained from FTIR spectra. It has been observed that the modification of the glass network structure occurs with change of SeO2 content, which reveals the dual role of SeO2 as a network modifier and a network former depending on composition. The dielectric constant as well as dielectric strength increases gradually with the increase of SeO2 content for low modifier oxide content (y), whereas they show a maximum for intermediate and highly modified glasses. The variation of the dielectric parameters correlates directly to the relative proportion of vibration mode of SeO32− ions, which is observed to vary in a similar fashion to dielectric parameters and is, thus in turn, related to the dual behavior of SeO2 as a modifier and a former depending on composition.
Longitudinal optical phonon-plasmon coupled modes of degenerate Al-doped ZnO films
Authors: Ding K. , Hu Q. C. , Lin W. W. , Huang J. K. , Huang F.
Published: July 2012

We have investigated the interaction between carriers and polar phonons by using Raman scattering spectroscopy in highly conductive Al-doped ZnO films grown by metalorganic chemical vapor deposition. Different from the longitudinal optical phonon-plasmon coupled modes (LOPPCM) observed in nondegenerate ZnO, an A1(LO)-like mode appears at the low frequency side of the uncoupled A1(LO) mode, and it monotonically shifts to higher frequencies and approaches to the uncoupled A1(LO) mode as Al composition increases. Based on line shape calculations, the A1(LO)-like mode is assigned to the large wave-vector LOPPCM arising from nonconserving scattering dominated by the Al impurity-induced Fröhlich mechanism. Benefiting from the nonmonotonic Al composition dependence of the electron density, it is revealed that the LOPPCM depends mainly on the doping level but not the carrier concentration.
Mild exercise increases dihydrotestosterone in hippocampus providing evidence for androgenic mediation of neurogenesis
Authors: Okamoto Masahiro , Hojo Yasushi , Inoue Koshiro , Matsui Takashi , Kawato Suguru , McEwen Bruce S. , Soya Hideaki
Published: July 2012

Mild exercise activates hippocampal neurons through the glutamatergic pathway and also promotes adult hippocampal neurogenesis (AHN). We hypothesized that such exercise could enhance local androgen synthesis and cause AHN because hippocampal steroid synthesis is facilitated by activated neurons viaN-methyl-D-aspartate receptors. Here we addressed this question using a mild-intense treadmill running model that has been shown to be a potent AHN stimulator. A mass-spectrometric analysis demonstrated that hippocampal dihydrotestosterone increased significantly, whereas testosterone levels did not increase significantly after 2 wk of treadmill running in both orchidectomized (ORX) and sham castrated (Sham) male rats. Furthermore, analysis of mRNA expression for the two isoforms of 5α-reductases (srd5a1,srd5a2) and for androgen receptor (AR) revealed that both increased in the hippocampus after exercise, even in ORX rats. All rats were injected twice with 5′-bromo-2′deoxyuridine (50 mg/kg body weight, i.p.) on the day before training. Mild exercise significantly increased AHN in both ORX and Sham rats. Moreover, the increase of doublecortin or 5′-bromo-2′deoxyuridine/NeuN-positive cells in ORX rats was blocked by s.c. flutamide, an AR antagonist. It was also found that application of an estrogen receptor antagonist, tamoxifen, did not suppress exercise-induced AHN. These results support the hypothesis that, in male animals, mild exercise enhances hippocampal synthesis of dihydrotestosterone and increases AHN via androgenenic mediation.
Erosion of case and agreement in Hindi heritage speakers
Authors: Montrul Silvina , Bhatt Rakesh , Bhatia Archna
Published: July 2012

Recent research has identified several vulnerable areas in heritage language grammars, among which morphosyntax is among the most affected. In this study, we report on the morphosyntactic competence of Hindi heritage speakers living in the U.S and show that these speakers have representational problems with ergative, accusative and dative case morphology, albeit to different degrees. Hindi is a split ergative language with a complex interaction of case and agreement. Transitive predicates in perfective aspect co-occur with subjects marked with ergative case (-ne) and object agreement. Animate specific direct objects are marked with the particle -ko, and so are the indirect objects and dative subjects. 21 Hindi native speakers and 28 Hindi heritage speakers completed a sociolinguistic questionnaire, a Hindi cloze test, an oral narrative task and a bimodal acceptability judgment task. The results showed significant differences between the fluent native speakers and the heritage speakers on all measures.
Microscale 1–3-type lead-free piezoelectric/ferrite composites fabricated by a modified dice-and-fill method
Authors: Xu Ying , Li Jing-Feng , Ma Jing , Nan Ce-Wen
Published: July 2012

This paper introduces a facile method to fabricate magnetoelectric (ME) composites with microscale lead-free piezoceramic pillars embedded in a ferrite matrix without high-temperature co-sintering. The microscale piezoceramic pillars with a sectional width of about 150 µm were obtained from lead-free piezoceramic discs by a dicing method. The spacing between the pillars was backfilled with cobalt ferrite (CFO) nanoparticles, and then a liquid epoxy was infiltrated into the backfilled spacing to bond the filled particles and the pillars. The ME property of the resultant 1–3-type piezoelectric/ferrite composites was verified and found to be significantly dependent on the filling density of the CFO powder, which could be adjusted by repeating the filling step. A maximum ME voltage response of up to 302 µV Oe−1 was obtained in a 700 µm high composite with pillars of 150 µm width and 200 µm spacing. The present method provides a potential way to fabricate finescale multiferroic composites for microdevice applications.
Human punishment is motivated by inequity aversion, not a desire for reciprocity
Authors: Raihani N. J. , McAuliffe K.
Published: July 2012

Humans involved in cooperative interactions willingly pay a cost to punish cheats. However, the proximate motives underpinning punitive behaviour are currently debated. Individuals who interact with cheats experience losses, but they also experience lower payoffs than the cheating partner. Thus, the negative emotions that trigger punishment may stem from a desire to reciprocate losses or from inequity aversion. Previous studies have not disentangled these possibilities. Here, we use an experimental approach to ask whether punishment is motivated by inequity aversion or by a desire for reciprocity. We show that humans punish cheats only when cheating produces disadvantageous inequity, while there is no evidence for reciprocity. This finding challenges the notion that punishment is motivated by a simple desire to reciprocally harm cheats and shows that victims compare their own payoffs with those of partners when making punishment decisions.
Identification of potential biophysical and molecular signalling mechanisms underlying hyaluronic acid enhancement of cartilage formation
Authors: Responte Donald J. , Natoli Roman M. , Athanasiou Kyriacos A.
Published: July 2012

This study determined the effects of exogenous hyaluronic acid (HA) on the biomechanical and biochemical properties of self-assembled bovine chondrocytes, and investigated biophysical and genetic mechanisms underlying these effects. The effects of HA commencement time, concentration, application duration and molecular weight were examined using histology, biomechanics and biochemistry. Additionally, the effects of HA application on sulphated glycosaminoglycan (GAG) retention were assessed. To investigate the influence of HA on gene expression, microarray analysis was conducted. HA treatment of developing neocartilage increased compressive stiffness onefold and increased sulphated GAG content by 35 per cent. These effects were dependent on HA molecular weight, concentration and application commencement time. Additionally, applying HA increased sulphated GAG retention within self-assembled neotissue. HA administration also upregulated 503 genes, including multiple genes associated with TGF-β1 signalling. Increased sulphated GAG retention indicated that HA could enhance compressive stiffness by increasing the osmotic pressure that negatively charged GAGs create. The gene expression data demonstrate that HA treatment differentially regulates genes related to TGF-β1 signalling, revealing a potential mechanism for altering matrix composition. These results illustrate the potential use of HA to improve cartilage regeneration efforts and better understand cartilage development.