bluuebunny/crossref_metadata_2025_split huggingface dataset:
MCMC design-based non-parametric regression for rare event. Application to nested risk computations
Authors: Fort Gersende , Gobet Emmanuel , Moulines Eric 
Published: February 2017

Abstract
We design and analyze an algorithm for estimating the mean of a
function of a conditional expectation when the outer expectation is related
to a rare event. The outer expectation is evaluated through the average along
the path of an ergodic Markov chain generated by a Markov chain Monte Carlo
sampler. The inner conditional expectation is computed as a non-parametric
regression, using a least-squares method with a general function
basis and a design given by the sampled Markov chain. We
establish non-asymptotic bounds for the

L
2

${L_{2}}$

-empirical risks associated to
this least-squares regression; this generalizes the error bounds usually
obtained in the case of i.i.d. observations. Global error bounds are also
derived for the nested expectation problem. Numerical results in the context
of financial risk computations illustrate the performance of the algorithms.
Dynamic Shaping of the Defensive Peripersonal Space through Predictive Motor Mechanisms: When the “Near” Becomes “Far”
Authors: Bisio Ambra , Garbarini Francesca , Biggio Monica , Fossataro Carlotta , Ruggeri Piero , Bove Marco 
Published: February 2017

The hand blink reflex is a subcortical defensive response, known to dramatically increase when the stimulated hand is statically positioned inside the defensive peripersonal space (DPPS) of the face. Here, we tested in a group of healthy human subjects the hand blink reflex in dynamic conditions, investigating whether the direction of the hand movements (up-to/down-from the face) could modulate it. We found that, on equal hand position, the response enhancement was present only when the hand approached to (and not receded from) the DPPS of the face. This means that, when the hand is close to the face but the subject is planning to move the hand down, the predictive motor system can anticipate the consequence of the movement: the “near” becomes “far.” We found similar results both in passive movement condition, when only afferent (visual and proprioceptive) information can be used to estimate the final state of the system, and in motor imagery task, when only efferent (intentional) information is available to predict the consequences of the movement. All these findings provide evidence that the DPPS is dynamically shaped by predictive mechanisms run by the motor system and based on the integration of feedforward and sensory feedback signals.SIGNIFICANCE STATEMENTThe defensive peripersonal space (DPPS) has a crucial role for survival, and its modulation is fundamental when we interact with the environment, as when we move our arms. Here, we focused on a defensive response, the hand blink reflex, known to increase when a static hand is stimulated inside the DPPS of the face. We tested the hand blink reflex in dynamic conditions (voluntary, passive, and imagined movements) and we found that, on equal hand position, the response enhancement was present only when the hand approached to (and not receded from) the DPPS of the face. This suggests that, through the integration of efferent and afferent signals, the safety boundary around the body is continuously shaped by the predictive motor system.
Diencephalic Size Is Restricted by a Novel Interplay Between GCN5 Acetyltransferase Activity and Retinoic Acid Signaling
Authors: Wilde Jonathan J. , Siegenthaler Julie A. , Dent Sharon Y.R. , Niswander Lee A. 
Published: February 2017

Diencephalic defects underlie an array of neurological diseases. Previous studies have suggested that retinoic acid (RA) signaling is involved in diencephalic development at late stages of embryonic development, but its roles and mechanisms of action during early neural development are still unclear. Here we demonstrate that mice lacking enzymatic activity of the acetyltransferase GCN5 ((Gcn5hat/hat)), which were previously characterized with respect to their exencephalic phenotype, exhibit significant diencephalic expansion, decreased diencephalic RA signaling, and increased diencephalic WNT and SHH signaling. Using a variety of molecular biology techniques in both cultured neuroepithelial cells treated with a GCN5 inhibitor and forebrain tissue from (Gcn5hat/hat) embryos, we demonstrate that GCN5, RARα/γ, and the poorly characterized protein TACC1 form a complex in the nucleus that binds specific retinoic acid response elements in the absence of RA. Furthermore, RA triggers GCN5-mediated acetylation of TACC1, which results in dissociation of TACC1 from retinoic acid response elements and leads to transcriptional activation of RA target genes. Intriguingly, RA signaling defects caused byin vitroinhibition of GCN5 can be rescued through RA-dependent mechanisms that require RARβ. Last, we demonstrate that the diencephalic expansion and transcriptional defects seen in (Gcn5hat/hat) mutants can be rescued with gestational RA supplementation, supporting a direct link between GCN5, TACC1, and RA signaling in the developing diencephalon. Together, our studies identify a novel, nonhistone substrate for GCN5 whose modification regulates a previously undescribed, tissue-specific mechanism of RA signaling that is required to restrict diencephalic size during early forebrain development.SIGNIFICANCE STATEMENTChanges in diencephalic size and shape, as well as SNPs associated with retinoic acid (RA) signaling-associated genes, have been linked to neuropsychiatric disorders. However, the mechanisms that regulate diencephalic morphogenesis and the involvement of RA signaling in this process are poorly understood. Here we demonstrate a novel role of the acetyltransferase GCN5 in a previously undescribed mechanism of RA signaling in the developing forebrain that is required to maintain the appropriate size of the diencephalon. Together, our experiments identify a novel nonhistone substrate of GCN5, highlight an essential role for both GCN5 and RA signaling in early diencephalic development, and elucidate a novel molecular regulatory mechanism for RA signaling that is specific to the developing forebrain.
Structural and Functional Cortical Connectivity Mediating Cross Education of Motor Function
Authors: Ruddy Kathy L. , Leemans Alexander , Woolley Daniel G. , Wenderoth Nicole , Carson Richard G. 
Published: February 2017

Cross-education (CE) is the process whereby training with one limb leads to subsequent improvement in performance by the opposite untrained limb. We used multimodal neuroimaging in humans to investigate the mediating neural mechanisms by relating quantitative estimates of functional and structural cortical connectivity to individual levels of interlimb transfer. Resting-state (rs)-fMRI and diffusion weighted imaging (DWI) scans were undertaken before unilateral ballistic wrist flexion training. The rs-fMRI sequence was repeated immediately afterward. The increase in performance of the untrained limb was 83.6% of that observed for the trained limb and significantly greater than that of a control group who undertook no training. Functional connectivity in the resting motor network between right and left supplementary motor areas (SMA) was elevated after training. These changes were not, however, correlated with individual levels of transfer. Analysis of the DWI data using constrained spherical deconvolution-based tractography indicated that fractional anisotropy and apparent fiber density in tracts connecting bilateral SMA were negatively correlated with and predictive of transfer. The findings suggest that interhemispheric interactions between bilateral SMA play an instrumental role in CE and that the structural integrity of the connecting white matter pathways influences the level of transfer.SIGNIFICANCE STATEMENTStrength or skill training with one limb also brings about improvements in the performance of the opposite, untrained limb. This phenomenon, termed cross-education (CE), has obvious potential for the rehabilitation of functional capacity that has been lost through brain insult or musculoskeletal injury. The neural mechanisms that give rise to CE are, however, poorly understood. We used a combination of neuroimaging methods to investigate the pathways in the human brain that mediate CE. We determined that the supplementary motor area (SMA) plays an important role in the interlimb transfer of performance gains and demonstrate that the quality of the white matter fibers connecting right and left SMA predicts the benefit that an individual derives from CE.
Desigualdades en la continuidad de la atención ambulatoria de población desplazada en Colombia, 2012–2013
Authors: Henríquez-Mendoza Giana María 
Published: February 2017

Objetivo Establecer desigualdades en la continuidad de la atención ambulatoria de la población desplazada con diagnóstico de depresión.Métodos Estudio transversal a partir del registro clínico, del periodo entre el 1 de junio de 2012 y 30 de junio de 2013, sobre las personas con diagnóstico de depresión y clasificadas según desplazamiento. Se usó el odds ratio para la asociación entre tipo de población y control profesional ambulatorio, ajustado por sexo, edad, afiliación y región.Resultados Sobre 74 713 registros: 3 149 de desplazados y 71 564 no desplazados; se encontró 24 % más atención ambulatoria en los no desplazados (OR: 1,24 p<0.001; IC 1,10-1,39), la ventaja fue mayor al ajustar por afiliación al sistema. En el grupo de desplazados se encontró mayor atención ambulatoria en los hombres frente a las mujeres (OR: 1,40 p<0.001 IC: 1,08-1,83). Fue mayor también la desventaja para aquellas, con respecto a mujeres no desplazadas (OR: 1,26 p<0.001 IC: 1,10-1,44). Si bien estos resultados se obtuvieron en la atención de depresión leve y moderada, no en grave, la primera fue diagnosticada en el 92 % de las personas.Discusión El registro de prestaciones demostró desigualdades en la continuidad de la atención ambulatoria y aunque su calidad ha mejorado, su cobertura todavía es incompleta. En el primer año con plan único del Sistema de Salud, parece que las coberturas no lograron por sí solas evitar diferencias en la atención de la población desplazada. Se necesita mejorar el registro y la interoperabilidad, para políticas de salud con enfoque de equidad.
Synthesis and characterization of periodic porous benzene-silica hybrid powders with cubic and hexagonal symmetries
Authors: Goletto Valérie , Bled Anne-Claire , Trimmel Gregor , Man Michel Wong Chi , Woo Hee-Gweon , Durand Dominique , Babonneau Florence 
Published: February 2017

AbstractOrganosilica powders with uniformly distributed bridging benzene groups have been synthesized from the condensation of bis- or tris-(triethoxysilyl)benzene in the presence of cetyltrimethylammoniumbromide. The syntheses were performed under strong acidic conditions and the organic groups were always incorporated without cleavage of the Si-C bonds as indicated by solid state MAS NMR studies. Depending on the nature of the precursors, materials with different ordering were obtained: a 2D-hexagonal (p6m) phase was formed from the 1,3-bis(triethoxysilyl)benzene, whereas the 1,4-bis(triethoxysilyl)benzene lead to a cubic Pm3n phase. The surfactant was removed either by solvent extraction or by controlled calcination, which did not affect the mesostructure of the materials.
Formation of hybrid colloids by suspension polycondensation in the presence of hydrophilic block copolymers
Authors: Gerardin Corine , Buissette Valérie , Gaudemet François , Anthony Olivier , Sanson Nicolas , Direnzo Francesco , Fajula François 
Published: February 2017

AbstractDouble hydrophilic block copolymers were used to control the growth of inorganic particles and directly prepare hybrid colloidal suspensions. Colloids of metal hydrous oxides were obtained by forced hydrolysis of metal ions in presence of the copolymers. The block copolymers contain a metal-complexing polyelectrolyte block and a stabilizing neutral block. The role of the first block is to ensure a controlled growth of the inorganic phase, while simultaneously, the second block ensures the colloidal stabilization. Phase diagrams presenting the conditions under which precipitation is inhibited are established. The nanoparticles are then characterized in terms of sizes, morphologies and surface charges. The main parameters controlling the size were identified: the copolymer-to-metal ratio and the metal prehydrolysis ratio. The synthesis steps were characterized. First, a key step of induced micellization of the hydrophilic copolymers leads to hybrid core-shell assemblies. The second step consists in mineralization of the micellar core. The suspension polycondensation leads to hairy particles whose morphologies depend on the nature of the metal and on synthesis parameters.
Periodic Mesoporous Organosilicas PMOs with Different Organic Bridging Groups: Synthesis and Characterization
Authors: Rebbin Vivian , Muth Olaf , Fröba Michael 
Published: February 2017

AbstractWe present results on new periodic mesoporous organosilicas synthesized with 1,4-bis(triethoxysilyl)benzene (BTEB), 1,2-bis(trimethoxysilyl)ethane (BTME) and bis[3-(trimethoxysilyl)propyl]amine (BTMPA). The materials show high inner surfaces up to 830 m2/g and pore diameters in the range of 2.7 to 3.7 nm depending on the structure directing agent used. In case of BTEB as precursor and triblock copolymer Pluronic P123 as structure directing agent exceptional thick pore walls were obtained (7.2 nm). Characterization was carried out by P-XRD, nitrogen physisorption analysis, thermoanalytical methods and IR spectroscopy.
Phase Transformations of Anatase TiO2 on Cation Intercalation from First Principles Simulation.
Authors: Koudriachova Marina V. , Harrison Nicholas M. , Leeuw Simon W. de 
Published: February 2017

AbstractThe phase transformations of anatase on Li-, H- and Na- intercalation are analyzed, for a variety of different insertion concentrations, using first principle calculations. Predicted structures are based on symmetry unconstrained optimization of all internal degrees of freedom and the unit cell shape and volume. The maximum insertion concentrations are determined, the phase stability of the predicted structures examined and the mechanism of the phase transformations discussed.
Large Scale Statistics for Computational Verification of Grain Growth Simulations with Experiments
Authors: Demirel Melik C. , Kuprat Andrew P. , George Denise C. , Straub Galen K. , Misra Amit , Alexander Kathleen , Rollett Anthony D. 
Published: February 2017

AbstractIt is known that by controlling microstructural development, desirable properties of materials can be achieved. The main objective of our research is to understand and control interface dominated material properties, and finally, to verify experimental results with computer simulations. We have previously showed a strong similarity between small-scale grain growth experiments and anisotropic three-dimensional simulations obtained from the Electron Backscattered Diffraction (EBSD) measurements [1]. Using the same technique, we obtained 5170-grain data from an Aluminum-film (120μm thick) with a columnar grain structure. Experimentally obtained starting microstructure and grain boundary properties are input for the three-dimensional grain growth simulation. In the computational model, minimization of the interface energy is the driving force for the grain boundary motion. The computed evolved microstructure is compared with the final experimental microstructure, after annealing at 550°C.
Роль кишкової мікробіоти в розвитку порушень ліпідного та вуглеводного обміну при стеатозі печінки у дітей
Authors: Zavgorodnya N.Yu. , Zygalo E.V. , Lukianenko O.Yu. , Babii S.A. 
Published: February 2017

У 34 дітей із різним ступенем стеатозу печінки був досліджений за допомогою водневого дихального тесту стан мікробіоти тонкого кишечника. Виявлений у третини дітей із стеатозом печінки (переважно третього ступеня) синдром надмірного бактеріального росту сприяв розвитку інсулінорезистентності, дисліпідемії, зокрема, ІІа типу (у 34,0 % дітей), ІІb типу (34,0 %), IV типу (17,0 %) та ізольованого зниження рівня холестерину ліпопротеїнів високої щільності (17,0 %).
Relações entre os movimentos reformistas educacionais do ensino de ciências nos Estados Unidos e Brasil na década de 1960
Authors: Azevedo Maicon , Selles Sandra , Lima-Tavares Daniele 
Published: February 2017

O presente artigo examina as relações entre dois movimentos educacionais que visaram reformar o ensino de Ciências em nível secundário nos Estados Unidos e no Brasil na década de 1960. O estudo apoia-se em referenciais do campo do currículo, em especial, na história das disciplinas escolares. Mobilizando esses referenciais, analisa-se o manual pedagógico de auxílio ao professor de Biologia (Biology Teachers’s Handbook), produzido em 1963 no âmbito de um dos projetos de reforma do currículo das escolas secundárias norte-americanas, e o Biological Sciences Curriculum Study (BSCS), que é traduzido e adaptado no contexto do movimento de renovação do ensino de ciências no Brasil neste período. A despeito das distinções entre a reforma norteamericana, da influência que exerce no ensino de Ciências brasileiro, e, sobretudo, da hegemonia exercida sobre o Brasil, argumenta-se em favor de bases epistemológicas comuns que sustentam o ideário reformista nesses países. Sob a liderança de Jerome Bruner e Joseph Schwab e com o protagonismo de eminentes cientistas, esta reforma anuncia uma ruptura das ideias escolanovistas de Dewey. Entretanto, a análise do manual sugere que esse ideário é ressignificado sem abandonar completamente suas bases.
Severe carotid stenosis and delay of reperfusion in endovascular stroke treatment: an Interventional Management of Stroke-III study
Authors: Gogela Steven L. , Gozal Yair M. , Zhang Bin , Tomsick Thomas A. , Ringer Andrew J. , Broderick Joseph P. , Khatri Pooja , Abruzzo Todd A. 
Published: February 2017

OBJECTIVEThe impact of extracranial carotid stenosis on interventional revascularization of acute anterior circulation stroke is unknown. The authors examined the effects of high-grade carotid stenosis on the results of endovascular treatment of patients in the Interventional Management of Stroke (IMS)-III trial.METHODSThe 278 patients in the endovascular arm of the IMS-III trial were categorized according to the degree of carotid stenosis as determined by angiography. In comparing patients with severe stenosis or occlusion (≥ 70%) to those without severe stenosis (< 70%), the authors evaluated the time to endovascular reperfusion, modified Thrombolysis in Cerebrovascular Infarction (mTICI) scores, 24-hour mean infarct volumes, symptomatic intracerebral hemorrhage rates, and modified Rankin Scale (mRS) scores at 90 days.RESULTSCompared with the 249 patients with less than 70% stenosis, patients with severe stenosis (n = 29) were found to have a significantly longer mean time to reperfusion (105.7 vs 77.7 minutes, p = 0.004); differences in mTICI scores, infarct volumes, hemorrhage rates, and mRS scores at 90 days did not reach statistical significance. Multiple regression analysis revealed that severe carotid stenosis (p < 0.0001) and higher baseline National Institutes of Health Stroke Scale (NIHSS) scores (p = 0.004) were associated with an increase in time to reperfusion. Older age (p < 0.0001), higher NIHSS score (p < 0.0001), and the absence of reperfusion (p = 0.001) were associated with worse clinical outcomes.CONCLUSIONSSevere ipsilateral ICA stenosis was associated with a significantly longer time to reperfusion in the IMS-III trial. Although these findings may not translate directly to modern devices, this 28-minute delay in reperfusion has significant implications, raising concern over the treatment of tandem ICA stenosis and downstream large-vessel occlusion.
Utility of MRI-based disproportionately enlarged subarachnoid space hydrocephalus scoring for predicting prognosis after surgery for idiopathic normal pressure hydrocephalus: clinical research
Authors: Shinoda Narihide , Hirai Osamu , Hori Shinya , Mikami Kazuyuki , Bando Toshiaki , Shimo Daisuke , Kuroyama Takahiro , Kuramoto Yoji , Matsumoto Masato , Ueno Yasushi 
Published: February 2017

OBJECTIVEThe presence of disproportionately enlarged subarachnoid space hydrocephalus (DESH) on brain imaging is a recognized finding of idiopathic normal pressure hydrocephalus (iNPH), but the features of DESH can vary across patients. The aim of this study was to evaluate the utility of MRI-based DESH scoring for predicting prognosis after surgery.METHODSIn this single-center, retrospective cohort study, the DESH score was determined by consensus between a group of neurosurgeons, neurologists, and a neuroradiologist based on the preoperative MRI findings of the patients with suspected iNPH. The DESH score was composed of the following 5 items, each scored from 0 to 2 (maximum score 10 points): ventriculomegaly, dilated sylvian fissures, tight high convexity, acute callosal angle, and focal sulcal dilation. The association between the DESH score and improvement of the scores on the modified Rankin Scale (mRS), iNPH Grading Scale (iNPHGS), Mini–Mental State Examination (MMSE), Trail Making Test-A (TMT-A), and Timed 3-Meter Up and Go Test (TUG-t) was examined. The primary end point was improvement in the mRS score at 1 year after surgery, and the secondary outcome measures were the iNPHGS, MMSE, TMT-A, and TUG-t scores at 1 year after surgery. Improvement was determined as improvement of 1 or more levels on mRS, ≥ 1 point on iNPHGS, ≥ 3 points on MMSE, a decrease of > 30% on TMT-A, and a decrease of > 10% on TUG-t.RESULTSThe mean DESH score for the 50 patients (mean age 77.6 ± 5.9 years) reviewed in this study was 5.58 ± 2.01. The mean rate of change in the mRS score was −0.50 ± 0.93, indicating an inverse correlation between the DESH score and rate of change in the mRS score (r = −0.749). Patients who showed no improvement in mRS score tended to have a low DESH score as well as low preoperative MMSE and TMT-A scores. There were no differences in the areas of deep white matter hyperintensity and periventricular hyperintensity on the images between patients with and without an improved mRS score (15.6% vs 16.7%, respectively; p = 1.000). The DESH score did differ significantly between patients with and without improved scores on the iNPHGS (6.39 ± 1.76 vs 4.26 ± 1.69, respectively; p < 0.001), MMSE (6.63 ± 1.82 vs 5.09 ± 1.93; p = 0.010), TMT-A (6.32 ± 1.97 seconds vs 5.13 ± 1.93 seconds; p = 0.042), and TUG-t (6.48 ± 1.81 seconds vs 4.33 ± 1.59 seconds; p < 0.001).CONCLUSIONSMRI-based DESH scoring is useful for the prediction of neurological improvement and prognosis after surgery for iNPH.