bluuebunny/crossref_metadata_2025_split huggingface dataset:
Slow Muscle Precursors Lay Down a Collagen XV Matrix Fingerprint to Guide Motor Axon Navigation
Authors: Guillon Emilie , Bretaud Sandrine , Ruggiero Florence 
Published: March 2016

The extracellular matrix (ECM) provides local positional information to guide motoneuron axons toward their muscle target. Collagen XV is a basement membrane component mainly expressed in skeletal muscle. We have identified two zebrafish paralogs of the humanCOL15A1gene,col15a1aandcol15a1b, which display distinct expression patterns. Here we show thatcol15a1bis expressed and deposited in the motor path ECM by slow muscle precursors also called adaxial cells. We further demonstrate that collagen XV-B deposition is both temporally and spatially regulated before motor axon extension from the spinal cord in such a way that it remains in this region after the adaxial cells have migrated toward the periphery of the myotome. Loss- and gain-of-function experiments in zebrafish embryos demonstrate thatcol15a1bexpression and subsequent collagen XV-B deposition and organization in the motor path ECM depend on a previously undescribed two-step mechanism involving Hedgehog/Gli andunplugged/MuSK signaling pathways.In silicoanalysis predicts a putative Gli binding site in thecol15a1bproximal promoter. Usingcol15a1bpromoter-reporter constructs, we demonstrate thatcol15a1bparticipates in the slow muscle genetic program as a direct target of Hedgehog/Gli signaling. Loss and gain ofcol15a1bfunction provoke pathfinding errors in primary and secondary motoneuron axons both at and beyond the choice point where axon pathway selection takes place. These defects result in muscle atrophy and compromised swimming behavior, a phenotype partially rescued by injection of asmyhc1:col15a1bconstruct. These reveal an unexpected and novel role for collagen XV in motor axon pathfinding and neuromuscular development.SIGNIFICANCE STATEMENTIn addition to the archetypal axon guidance cues, the extracellular matrix provides local information that guides motor axons from the spinal cord to their muscle targets. Many of the proteins involved are unknown. Using the zebrafish model, we identified an unexpected role of the extracellular matrix collagen XV in motor axon pathfinding. We show that the synthesis of collagen XV-B by slow muscle precursors and its deposition in the common motor path are dependent on a novel two-step mechanism that determines axon decisions at a choice point during motor axonogenesis. Zebrafish and humans use common molecular cues and regulatory mechanisms for the neuromuscular system development. And as such, our study revealsCOL15A1as a candidate gene for orphan neuromuscular disorders.
Prefrontal Cortex Structure Predicts Training-Induced Improvements in Multitasking Performance
Authors: Verghese Ashika , Garner K.G. , Mattingley Jason B. , Dux Paul E. 
Published: March 2016

The ability to perform multiple, concurrent tasks efficiently is a much-desired cognitive skill, but one that remains elusive due to the brain's inherent information-processing limitations. Multitasking performance can, however, be greatly improved through cognitive training (Van Selst et al., 1999, Dux et al., 2009). Previous studies have examined how patterns of brain activity change following training (for review, see Kelly and Garavan, 2005). Here, in a large-scale human behavioral and imaging study of 100 healthy adults, we tested whether multitasking training benefits, assessed using a standard dual-task paradigm, are associated with variability in brain structure. We found that the volume of the rostral part of the left dorsolateral prefrontal cortex (DLPFC) predicted an individual's response to training. Critically, this association was observed exclusively in a task-specific training group, and not in an active-training control group. Our findings reveal a link between DLPFC structure and an individual's propensity to gain from training on a task that taps the limits of cognitive control.SIGNIFICANCE STATEMENTCognitive “brain” training is a rapidly growing, multibillion dollar industry (Hayden, 2012) that has been touted as the panacea for a variety of disorders that result in cognitive decline. A key process targeted by such training is “cognitive control.” Here, we combined an established cognitive control measure, multitasking ability, with structural brain imaging in a sample of 100 participants. Our goal was to determine whether individual differences in brain structure predict the extent to which people derive measurable benefits from a cognitive training regime. Ours is the first study to identify a structural brain marker—volume of left hemisphere dorsolateral prefrontal cortex—associated with the magnitude of multitasking performance benefits induced by training at an individual level.
Requirement for Microglia for the Maintenance of Synaptic Function and Integrity in the Mature Retina
Authors: Wang Xu , Zhao Lian , Zhang Jun , Fariss Robert N. , Ma Wenxin , Kretschmer Friedrich , Wang Minhua , Qian Hao hua , Badea Tudor C. , Diamond Jeffrey S. , Gan Wen-Biao , Roger Jerome E. , Wong Wai T. 
Published: March 2016

Microglia, the principal resident immune cell of the CNS, exert significant influence on neurons during development and in pathological situations. However, if and how microglia contribute to normal neuronal function in the mature uninjured CNS is not well understood. We used the model of the adult mouse retina, a part of the CNS amenable to structural and functional analysis, to investigate the constitutive role of microglia by depleting microglia from the retina in a sustained manner using genetic methods. We discovered that microglia are not acutely required for the maintenance of adult retinal architecture, the survival of retinal neurons, or the laminar organization of their dendritic and axonal compartments. However, sustained microglial depletion results in the degeneration of photoreceptor synapses in the outer plexiform layer, leading to a progressive functional deterioration in retinal light responses. Our results demonstrate that microglia are constitutively required for the maintenance of synaptic structure in the adult retina and for synaptic transmission underlying normal visual function. Our findings on constitutive microglial function are relevant in understanding microglial contributions to pathology and in the consideration of therapeutic interventions that reduce or perturb constitutive microglial function.SIGNIFICANCE STATEMENTMicroglia, the principal resident immune cell population in the CNS, has been implicated in diseases in the brain and retina. However, how they contribute to the everyday function of the CNS is unclear. Using the model of the adult mouse retina, we examined the constitutive role of microglia by depleting microglia from the retina. We found that in the absence of microglia, retinal neurons did not undergo overt cell death or become structurally disorganized in their processes. However, connections between neurons called synapses begin to break down, leading to a decreased ability of the retina to transmit light responses. Our results indicate that retinal microglia contribute constitutively to the maintenance of synapses underlying healthy vision.
Integration of Visual and Proprioceptive Limb Position Information in Human Posterior Parietal, Premotor, and Extrastriate Cortex
Authors: Limanowski Jakub , Blankenburg Felix 
Published: March 2016

The brain constructs a flexible representation of the body from multisensory information. Previous work on monkeys suggests that the posterior parietal cortex (PPC) and ventral premotor cortex (PMv) represent the position of the upper limbs based on visual and proprioceptive information. Human experiments on the rubber hand illusion implicate similar regions, but since such experiments rely on additional visuo-tactile interactions, they cannot isolate visuo-proprioceptive integration. Here, we independently manipulated the position (palm or back facing) of passive human participants' unseen arm and of a photorealistic virtual 3D arm. Functional magnetic resonance imaging (fMRI) revealed that matching visual and proprioceptive information about arm position engaged the PPC, PMv, and the body-selective extrastriate body area (EBA); activity in the PMv moreover reflected interindividual differences in congruent arm ownership. Further, the PPC, PMv, and EBA increased their coupling with the primary visual cortex during congruent visuo-proprioceptive position information. These results suggest that human PPC, PMv, and EBA evaluate visual and proprioceptive position information and, under sufficient cross-modal congruence, integrate it into a multisensory representation of the upper limb in space.SIGNIFICANCE STATEMENTThe position of our limbs in space constantly changes, yet the brain manages to represent limb position accurately by combining information from vision and proprioception. Electrophysiological recordings in monkeys have revealed neurons in the posterior parietal and premotor cortices that seem to implement and update such a multisensory limb representation, but this has been difficult to demonstrate in humans. Our fMRI experiment shows that human posterior parietal, premotor, and body-selective visual brain areas respond preferentially to a virtual arm seen in a position corresponding to one's unseen hidden arm, while increasing their communication with regions conveying visual information. These brain areas thus likely integrate visual and proprioceptive information into a flexible multisensory body representation.
Interneurons Differentially Contribute to Spontaneous Network Activity in the Developing Hippocampus Dependent on Their Embryonic Lineage
Authors: Wester Jason C. , McBain Chris J. 
Published: March 2016

Spontaneously generated network activity is a hallmark of developing neural circuits, and plays an important role in the formation of synaptic connections. In the rodent hippocampus, this activity is observedin vitroas giant depolarizing potentials (GDPs) during the first postnatal week. Interneurons importantly contribute to GDPs, due to the depolarizing actions of GABA early in development. While they are highly diverse, cortical interneurons can be segregated into two distinct groups based on their embryonic lineage from either the medial or caudal ganglionic eminences (MGE and CGE). There is evidence suggesting CGE-derived interneurons are important for GDP generation; however, their contribution relative to those from the MGE has never been directly tested. Here, we optogenetically inhibited either MGE- or CGE-derived interneurons in a region-specific manner in mouse neonatal hippocampusin vitro. In CA1, where interneurons are the primary source of recurrent excitation, we found that those from the MGE strongly and preferentially contributed to GDP generation. Furthermore, in dual whole-cell patch recordings in neonatal CA1, MGE interneurons formed synaptic connections to and from neighboring pyramidal cells at a much higher rate than those from the CGE. These MGE interneurons were commonly perisomatic targeting, in contrast to those from the CGE, which were dendrite targeting. Finally, inhibiting MGE interneurons in CA1 suppressed GDPs in CA3 and vice versa; conversely, they could also trigger GDPs in CA1 that propagated to CA3 and vice versa. Our data demonstrate a key role for MGE-derived interneurons in both generating and coordinating GDPs across the hippocampus.SIGNIFICANCE STATEMENTDuring nervous system development, immature circuits internally generate rhythmic patterns of electrical activity that promote the establishment of synaptic connections. Immature interneurons are excitatory rather than inhibitory and actively contribute to the generation of these spontaneous network events, referred to as giant depolarizing potentials (GDPs) in the hippocampus. Interneurons can be generally separated into two distinct groups based on their origin in the embryo from the medial or caudal ganglionic eminences (MGE and CGE). Here we show that MGE interneurons play a dominant role in generating GDPs compared with their CGE counterparts. They accomplish this due to their high synaptic connectivity within the local circuitry. Finally, they can control network activity across large regions of the developing hippocampus.
A Multifaceted Approach to Improving Outcomes in the NICU: The Pediatrix 100 000 Babies Campaign
Authors: Ellsbury Dan L. , Clark Reese H. , Ursprung Robert , Handler Darren L. , Dodd Elizabeth D. , Spitzer Alan R. 
Published: March 2016

BACKGROUND AND OBJECTIVE:
Despite advances in neonatal medicine, infants requiring neonatal intensive care continue to experience substantial morbidity and mortality. The purpose of this initiative was to generate large-scale simultaneous improvements in multiple domains of care in a large neonatal network through a program called the “100,000 Babies Campaign.”

METHODS:
Key drivers of neonatal morbidity and mortality were identified. A system for retrospective morbidity and mortality review was used to identify problem areas for project prioritization. NICU system analysis and staff surveys were used to facilitate reengineering of NICU systems in 5 key driver areas. Electronic health record–based automated data collection and reporting were used. A quality improvement infrastructure using the Kotter organizational change model was developed to support the program.

RESULTS:
From 2007 to 2013, data on 422 877 infants, including a subset with birth weight of 501 to 1500 g (n = 58 555) were analyzed. Key driver processes (human milk feeding, medication use, ventilator days, admission temperature) all improved (P &lt; .0001). Mortality, necrotizing enterocolitis, retinopathy of prematurity, bacteremia after 3 days of life, and catheter-associated infection decreased. Survival without significant morbidity (necrotizing enterocolitis, severe intraventricular hemorrhage, severe retinopathy of prematurity, oxygen use at 36 weeks’ gestation) improved.

CONCLUSIONS:
Implementation of a multifaceted quality improvement program that incorporated organizational change theory and automated electronic health record–based data collection and reporting program resulted in major simultaneous improvements in key neonatal processes and outcomes.
Iron Supplementation in Pregnancy or Infancy and Motor Development: A Randomized Controlled Trial
Authors: Angulo-Barroso Rosa M. , Li Ming , Santos Denise C.C. , Bian Yang , Sturza Julie , Jiang Yaping , Kaciroti Niko , Richards Blair , Lozoff Betsy 
Published: March 2016

BACKGROUND AND OBJECTIVE:Insufficient iron levels for optimal fetal and infant development is a concern during pregnancy and infancy. The goal of this study was to assess the effects of iron supplementation in pregnancy and/or infancy on motor development at 9 months.METHODS:The study was a randomized controlled trial (RCT) of infancy iron supplementation linked to an RCT of pregnancy iron supplementation, conducted in Hebei, China. A total of 1482 infants were randomly assigned to receive placebo (n = 730) or supplemental iron (n = 752) from 6 weeks to 9 months. Gross motor development (assessed by using the Peabody Developmental Motor Scale, Second Edition, instrument) was the primary outcome. Neurologic integrity and motor quality were secondary outcomes.RESULTS:Motor outcome was available for 1196 infants, divided into 4 supplementation period groups: (1) placebo in pregnancy/placebo in infancy (n = 288); (2) placebo in pregnancy/iron in infancy (n = 305); (3) iron in pregnancy/placebo in infancy (n = 298); and (4) iron in pregnancy/iron in infancy (n = 305). Using the Peabody Developmental Motor Scale, instrument, iron supplementation in infancy but not pregnancy improved gross motor scores: overall, P &lt; .001; reflexes, P = .03; stationary, P &lt; .001; and locomotion, P &lt; .001. Iron supplementation in infancy improved motor scores by 0.3 SD compared with no supplementation or supplementation during pregnancy alone. Effects of iron supplementation in infancy alone were similar to effects with iron in both pregnancy and infancy.CONCLUSIONS:The RCT design supports the causal inference that iron supplementation in infancy, with or without iron supplementation in pregnancy, improved gross motor test scores at 9 months.
El libro de Fenggang Yang, Religion in China. Survival & Revival under Communist Rule
Authors: Martínez Esquivel Ricardo 
Published: March 2016

<p>El autor realiza una lectura crítica del libro <em>Religion in China. Survival &amp; Revival under Communist Rule </em>del especialista de origen chino Fenggang Yang (publicado en 2012), durante el gobierno de Mao Zedong y el Partido Comunista Chino y su marcado interés en la secularización del pueblo por medio del ateísmo.</p><div> </div>
十八岁出门远行 “Partir lejos de casa a los dieciocho” de Yu Hua余华
Authors: Rodríguez Durán Pablo 
Published: March 2016

<p>“Partir lejos de casa a los dieciocho” es un cuento que representa un tipo de corriente literaria, nacida a partir del desencanto con las manifestaciones artísticas del realismo socialista. En el estilo indeterminado de Yu Hua, puede entreverse la misma indeterminación en las emociones de un joven viajero, quien se encuentra en la transición de la infancia a la edad adulta. Una China convulsionada como escenario y un nuevo enfoque del individuo, en la literatura y en la vida.</p><div> </div>
Determination of Critical Stress for Dynamic Recrystallization of a High-Mn Austenitic TWIP Steel Micro-Alloyed with Vanadium
Authors: García-Mora Elvira , Mejía Ignacio , Reyes-Calderón Francisco , Cabrera José M. 
Published: March 2016

ABSTRACTWhen high strength and high ductility are required, the Twinning Induced Plasticity steels are an excellent choice. Their mechanical advantages are perfectly known in the automotive industry. Then, they are currently deeply studied. During the deformation at high temperature, TWIP steel experiences dynamic recrystallization. This mechanism results from dislocation interactions, and it depends of temperature, stress, strain, and strain rate. Experimental data give the maximum stress reached by the material, but the critical stress which determinates the DRX onset must be calculated from the strain hardening rate. Both stress and strain change simultaneously, and this variation gives the analytic data to determine σc, which is located at the inflection point of θ-σ plot. The main purpose of this paper was to study how the chemical composition and the experimental parameters (temperature and strain rate) affect the DRX, by the calculation and analysis of the σcvalues. Hot compression tests were applied to a pair of TWIP steels to compare the DRX onset and its relationship with the vanadium addition. The experimental variables were temperature and strain rate. The true stress–true strain plots were used to calculate σcby cutting data up to a previous point before the σpvalue, then, a polynomial fit and derivation were applied. The Zener-Hollomon parameter (Z) versus the stresses (peak and critical) plots show how the micro-alloying element vanadium improves the strain hardening in the analyzed TWIP steels.
Porous Silicon Nanostructured Materials for Sensing Applications: Molecular Assembling and Electrochemical or Optical Evaluation
Authors: Márquez J. , De la Cruz-Guzmán M. , Cházaro L.F. , Palestino G. 
Published: March 2016

ABSTRACTPorous silicon (PSi) combines the potential of miniaturization with a very large surface area. The PSi surface can be chemically modified resulting in a high sensitivity (low detection threshold) device for chemical and biomolecular sensing. In previous work, we have shown that redox proteins and fluorescent ligands can be infiltrated into PSi (PSiMc) structures. The hybrid devices have shown interesting new properties produced by the coupling of the individual properties of PSi nanostructures and the modifiers. In this work, we have obtained a PSiMc/redox protein bioelectrode, which presents a quasi-reversible electrochemical response. This effect was attributed to the semiconducting nature of the PSi substrate and to the functional groups of the crosslinking molecules (MPTS), which together produce a capacitive effect on the device. On the other hand, the chemical modification of PSiMc with fluorescent ligands allowed us to fabricate fluorescent PSi hybrid nanostructures, which were tested for the detection of environmental pollutants such as heavy metals (specifically Hg2+). We found that the selectivity of this optical device depends on the selected recognizing molecule. The captured metal induces the formation of a metallic complex that shows higher fluorescence compared with the sensor device. These results demonstrate the viability of using porous silicon as optical sensors and electrochemical biosensors. The infiltration of fluorescent recognizing molecules and proteins into the PSi matrix were evaluated by specular reflectance, FTIR spectroscopy, fluorescence spectroscopy and cyclic voltammetry.
Effect of Mechanical Activation on the Synthesis of Ba-Celsian and Sr-Celsian using Precursor Mixtures Containing Coal Fly Ash
Authors: Lopez-Badillo Claudia M. , López-Cuevas Jorge , Gutiérrez-Chavarría Carlos A. , Rodríguez-Galicia José L. , Múzquiz-Ramos Elia M. 
Published: March 2016

ABSTRACTBaAl2Si2O8 and SrAl2Si2O8 were synthesized by solid-state reaction of stoichiometric mixtures of either BaCO3 or SrCO3 with coal fly ash and Al2O3. The mixtures were mechanically activated in an attrition mill for up to 12 h and then reaction-sintered at 900-1300 °C, aiming to promote the formation of BaAl2Si2O8 and SrAl2Si2O8 as well as the conversion from their hexagonal (Hexacelsian) into their monoclinic (Celsian) forms, which is associated with improved mechanical properties in the sintered materials. Especially in the case of SrAl2Si2O8, the formation of Celsian was favored at relatively low sintering temperatures by increasing milling time. Although only the SrAl2Si2O8 composition was fully converted into Celsian, the Hexacelsian to Celsian conversions obtained for the mechanically-activated BaAl2Si2O8 composition were significantly higher than those previously reported in the literature for this compound. This could be attributed to the use of coal fly ash as raw material, which contains mineralizers that promote the mentioned conversion.
Numerical Simulation of Rotary Forging Inconel 718 Superalloy Applied to Aeronautical Components
Authors: Loyda A. , Hernández-Muñoz G.M. , Reyes-Osorio L.A. , Zambrano P. , Montemayor-Ibarra F. 
Published: March 2016

ABSTRACTNowadays the aeronautical industry keeps strict quality standards in its dimensional specifications, mechanical properties and microstructural characteristics. Therefore, the involved manufacturing processes require keeping high standards. The nickel based superalloys are present in many components of the jet engines, being the Inconel 718MR superalloy the most common, making up to 50% of the jet engine. This is designed to resist high temperatures, corrosion and creep. The process of rotary forging is a manufacturing process that is currently under scientific and technological development in the aeronautical industry. An Avrami model coupled with a commercial FEM platform (DEFORMTM 3D) was developed to evaluate the average grain size, as a function of the working conditions at 980 °C and 1000 °C. The results provide a better understanding of the influence of temperature in the grain size evolution during the rotary forging process, compared with previous reports.