bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Rapid Cytoplasmic Mechanism for PI3 Kinase Regulation by the Nuclear Thyroid Hormone Receptor, TRβ, and Genetic Evidence for Its Role in the Maturation of Mouse Hippocampal Synapses In Vivo
Authors: Martin Negin P. , Marron Fernandez de Velasco Ezequiel , Mizuno Fengxia , Scappini Erica L. , Gloss Bernd , Erxleben Christian , Williams Jason G. , Stapleton Heather M. , Gentile Saverio , Armstrong David L. 
Published: June 2014

Abstract
Several rapid physiological effects of thyroid hormone on mammalian cells in vitro have been shown to be mediated by the phosphatidylinositol 3-kinase (PI3K), but the molecular mechanism of PI3K regulation by nuclear zinc finger receptor proteins for thyroid hormone and its relevance to brain development in vivo have not been elucidated. Here we show that, in the absence of hormone, the thyroid hormone receptor TRβ forms a cytoplasmic complex with the p85 subunit of PI3K and the Src family tyrosine kinase, Lyn, which depends on two canonical phosphotyrosine motifs in the second zinc finger of TRβ that are not conserved in TRα. When hormone is added, TRβ dissociates and moves to the nucleus, and phosphatidylinositol (3, 4, 5)-trisphosphate production goes up rapidly. Mutating either tyrosine to a phenylalanine prevents rapid signaling through PI3K but does not prevent the hormone-dependent transcription of genes with a thyroid hormone response element. When the rapid signaling mechanism was blocked chronically throughout development in mice by a targeted point mutation in both alleles of Thrb, circulating hormone levels, TRβ expression, and direct gene regulation by TRβ in the pituitary and liver were all unaffected. However, the mutation significantly impaired maturation and plasticity of the Schaffer collateral synapses on CA1 pyramidal neurons in the postnatal hippocampus. Thus, phosphotyrosine-dependent association of TRβ with PI3K provides a potential mechanism for integrating regulation of development and metabolism by thyroid hormone and receptor tyrosine kinases.
Biochemical and Cell Biological Properties of the Human Prohormone Convertase 1/3 Ser357Gly Mutation: A PC1/3 Hypermorph
Authors: Blanco Elias H. , Peinado Juan R. , Martín Martín G. , Lindberg Iris 
Published: June 2014

AbstractSatiety and appetite signaling are accomplished by circulating peptide hormones. These peptide hormones require processing from larger precursors to become bioactive, often by the proprotein convertase 1/3 (PC1/3). Several subcellular maturation steps are necessary for PC1/3 to achieve its optimal enzymatic activity. Certain PC1/3 variants found in the general population slightly attenuate its enzymatic activity and are associated with obesity and diabetes. However, mutations that increase PC1/3 activity and/or affect its specificity could also have physiological consequences. We here present data showing that the known human Ser357Gly PC1/3 mutant (PC1/3S357G) represents a PC1/3 hypermorph. Conditioned media from human embryonic kidney-293 cells transfected with PC1/3WT and PC1/3S357G were collected and enzymatic activity characterized. PC1/3S357G exhibited a lower calcium dependence; a higher pH optimum (neutral); and a higher resistance to peptide inhibitors than the wild-type enzyme. PC1/3S357G exhibited increased cleavage to the C-terminally truncated form, and kinetic parameters of the full-length and truncated mutant enzymes were also altered. Lastly, the S357G mutation broadened the specificity of the enzyme; we detected PC2-like specificity on the substrate proCART, the precursor of the cocaine- and amphetamine regulated transcript neuropeptide known to be associated with obesity. The production of another anorexigenic peptide normally synthesized only by PC2, αMSH, was increased when proopiomelanocortin was coexpressed with PC1/3S357G. Considering the aberrant enzymatic profile of PC1/3S357G, we hypothesize that this enzyme possesses unusual processing activity that may significantly change the profile of circulating peptide hormones.
Regulation of GLUT Transporters by Flavonoids in Androgen-Sensitive and -Insensitive Prostate Cancer Cells
Authors: Gonzalez-Menendez Pedro , Hevia David , Rodriguez-Garcia Aida , Mayo Juan C. , Sainz Rosa M. 
Published: June 2014

AbstractCancer cells show different metabolic requirements from normal cells. In prostate cancer, particularly, glycolytic metabolism differs in androgen-responsive and nonresponsive cells. In addition, some natural compounds with antiproliferative activities are able to modify glucose entry into cells by either modulating glucose transporter (GLUT) expression or by altering glucose binding. The aim of this work was to study the regulation of some GLUTs (GLUT1 and GLUT4) in both androgen-sensitive (LNCaP) and -insensitive (PC-3) prostate cancer cells by 4 structurally different flavonoids (ie, genistein, phloretin, apigenin, and daidzein). Glucose uptake was measured using nonradiolabeled 2-deoxyglucose. The evaluation of protein levels as well as subcellular distribution of GLUT1/4 were analyzed by Western blot and immunocytochemistry, respectively. Androgen-insensitive LNCaP-R and androgen-sensitive PC-3-AR cells were used to study the effect of androgen signaling. Additionally, a docking simulation was employed to compare interactions between flavonoids and XylE, a bacterial homolog of GLUT1 to -4. Results show for the first time the presence of functionally relevant GLUT4 in prostate cancer cells. Furthermore, differences in GLUT1 and GLUT4 levels and glucose uptake were found, without differences on subcellular distribution, after incubation with flavonoids. Docking simulation showed that all compounds interact with the same location of transporters. More importantly, differences between androgen-sensitive and -insensitive prostate cancer cells were found in both GLUT protein levels and glucose uptake. Thus, phenotypic characteristics of prostate cancer cells are responsible for the different effects of these flavonoids in glucose uptake and in GLUT expression rather than their structural differences, with the most effective in reducing cell growth being the highest in modifying glucose uptake and GLUT levels.
Shape and position of the node and notochord along the bilateral plane of symmetry are regulated by cell–extracellular matrix interactions
Authors: Pulina Maria , Liang Dong , Astrof Sophie 
Published: June 2014

ABSTRACT
The node and notochord (and their equivalents in other species) are essential signaling centers, positioned along the plane of bilateral symmetry in developing vertebrate embryos. However, genes and mechanisms regulating morphogenesis of these structures and their placement along the embryonic midline are not well understood. In this work, we provide the first evidence that the position of the node and the notochord along the bilateral plane of symmetry are under genetic control and are regulated by integrin α5β1 and fibronectin in mice. We found that the shape of the node is often inverted in integrin α5-null and fibronectin-null mutants, and that the positioning of node and the notochord is often skewed away from the perceived plane of embryonic bilateral of symmetry. Our studies also show that the shape and position of the notochord are dependent on the shape and embryonic placement of the node. Our studies suggest that fibronectin regulates the shape of the node by affecting apico-basal polarity of the nodal cells. Taken together, our data indicate that cell–extracellular matrix interactions mediated by integrin α5β1 and fibronectin regulate the geometry of the node as well as the placement of the node and notochord along the plane of bilateral symmetry in the mammalian embryo.
Fission yeast mtr1p regulates interphase microtubule cortical dwell-time
Authors: Carlier-Grynkorn Frédérique , Ji Liang , Fraisier Vincent , Lombard Berangère , Dingli Florent , Loew Damarys , Paoletti Anne , Ronot Xavier , Tran Phong T. 
Published: June 2014

ABSTRACT
The microtubule cytoskeleton plays important roles in cell polarity, motility and division. Microtubules inherently undergo dynamic instability, stochastically switching between phases of growth and shrinkage. In cells, some microtubule-associated proteins (MAPs) and molecular motors can further modulate microtubule dynamics. We present here the fission yeast mtr1+, a new regulator of microtubule dynamics that appears to be not a MAP or a motor. mtr1-deletion (mtr1Δ) primarily results in longer microtubule dwell-time at the cell tip cortex, suggesting that mtr1p acts directly or indirectly as a destabilizer of microtubules. mtr1p is antagonistic to mal3p, the ortholog of mammalian EB1, which stabilizes microtubules. mal3Δ results in short microtubules, but can be partially rescued by mtr1Δ, as the double mutant mal3Δ mtr1Δ exhibits longer microtubules than mal3Δ single mutant. By sequence homology, mtr1p is predicted to be a component of the ribosomal quality control complex. Intriguingly, deletion of a predicted ribosomal gene, rps1801, also resulted in longer microtubule dwell-time similar to mtr1Δ. The double-mutant mal3Δ rps1801Δ also exhibits longer microtubules than mal3Δ single mutant alone. Our study suggests a possible involvement of mtr1p and the ribosome complex in modulating microtubule dynamics.
State-to-State Reaction Dynamics in Collision of Deuterium Molecule with Excited-State Nitrogen Atom
Authors: Lü Rui , Chu Tian-shu , Chang Zhi-shang , Zhang Wen-qing 
Published: June 2014

Abstract
The collision dynamics of deuterium molecule with excited-state nitrogen atom has been investigated at a state-to-state dynamic level by using the real wave packet method. The energy-dependent behavior of the differential and integral cross sections, especially from the reactant quantum states of v = 0, j = 0 to the product quantum states of j′ = 0–7, v′ = 0–5, is presented and discussed for total energies up to 0.4 eV. The present study predicted noninverted vibrational populations and inverted rotational populations in product rovibrational distributions. Comparison of the theoretical total differential cross section with the previous experimental measurement has also been presented and discussed.
La docencia universitaria en Argentina Obstáculos en la carrera académica
Authors: García de Fanelli Ana , Moguillansky Marina 
Published: June 2014

El artículo analiza el funcionamiento de los mecanismos de acceso y promoción de los docentes dentro de las universidades nacionales de Argentina. Para ello se realizaron 156 entrevistas en profundidad con docentes de siete universidades nacionales y dos campos disciplinarios, biología y administración. Los docentes destacan la existencia de fallas en los concursos públicos como uno de los principales obstáculos, tanto respecto al acceso a cargos de mayor categoría como de superior dedicación horaria. Las observaciones críticas apuntan a la inestabilidad laboral, la dependencia de los concursos con respecto al presupuesto y su politización, los criterios de evaluación de los candidatos, la composición de los jurados y la competencia y sus efectos en el ambiente laboral.Algunas universidades han tratado de superar los problemas que acarrean los concursos públicos a través de la incorporación de la “carrera docente” asegurando estabilidad en el cargo vía un sistema de evaluación permanente del desempeño docente. Al hacerlo han tenido que enfrentar nuevas restricciones: fondos insuficientes para garantizar las promociones, complejos sistemas de evaluación con resistencias de los docentes y altos costos de gestión y estancamiento de la estructura ocupacional tras la garantía de estabilidad de los cargos.
Rheological Characteristics of a New Kind of Friction-Promoting Grease
Authors: Ma Wan , Zhu Zhencai , Peng Yuxing , Chen Guoan 
Published: June 2014

Abstract
The main objective of this work was to study the rheological characteristics of a newly developed friction-promoting grease (FPG) in China that has been widely used for the lubrication and protection of multi-rope friction hoists. A stereo microscope was used to determine the microstructure of the grease. A series of rheological tests were performed on a cone-plate rheometer to investigate the thixotropic shear-thinning behavior under several constant temperature conditions and examine the changes in the apparent viscosity when the temperature is increased while the shear rate is kept constant. Experimental results indicated that within the temperature range of 20°C to 30°C, a lower temperature could lead to a stronger thixotropy of the FPG. Within the temperature range of 20°C to 160°C, a lower temperature could result in a greater yield stress and a more intense shear-thinning behavior of the FPG, which was in good agreement with Sisko’s model. It should be noted that at 170°C and 180°C, the apparent viscosity showed a slightly ascending trend at low shear rates and a stable value was gradually approached as the shear rate increased. Under a constant shear rate, the apparent viscosity remained stable after decreasing and then finally increased with an increase in the temperature.
Estimation of the Dynamic Properties of Epoxy Glass Fabric Composites with Natural Rubber Particle Inclusions
Authors: H. Ravi Sankar  , R.R. Srikant  , P. Vamsi Krishna  , V. Bhujanga Rao  , P. Bangaru Babu  
Published: June 2014

Conventional materials are being replaced in the field of engineering by composite materials, due to their tailorable properties and high specific properties. These materials are extensively used in structural applications. Damping is one of the important properties of the materials used in structures, and needs to be enhanced in order to reduce structural vibrations. In the present work, the improvement of the material damping of glass fabric epoxy composites with particle rubber inclusions is studied. The effect of particle size on the damping and stiffness parameters at different frequencies and temperatures is studied experimentally. Considerable enhancement in damping without significant reduction in stiffness is observed at lower particle sizes. The damping property in both bending and shear modes is more with 0.254 mm rubber particle inclusions among the selected sizes. A lower reduction in stiffness is observed with the inclusion of lower particle sizes (0.254 mm and 0.09 mm) when compared with higher particle sizes. An ANN-based prediction model is developed to predict these properties for a given frequency/temperature and particle size. The predicted values are very close to the experimental values with an maximum error of 5%.
Pattern Development for Manufacturing Applications with Fused Deposition Modelling – A Case Study
Authors: H. K. Garg  , R. Singh  
Published: June 2014

The purpose of this paper is to examine the suitability of fused deposition modelling (FDM), for the production of a pattern that can be used in direct manufacturing applications. In this work, the benchmark was identified and its best part orientation in a FDM machine was located through experimentation. Control charts and process capability histogram were drawn to assess the process capability of the FDM process. The micro hardness of the prepared sample was measured to check the suitability of the process for investment casting applications. Further dimensional accuracy of patterns was established by IT grades as per the ISO standard UNI EN 20286-I (1995). It was observed that the performance indices for all the dimensions in the present study are greater than 1. The study of photo micrographs using SEM gave an insight into the properties of the component (produced by FDM). This study highlights that the tolerance grades for ABS plastics are consistent with the permissible range of tolerance grades as per the ISO standard UNI EN 20286-I (1995) and DIN16901 standard.
Effect of Ta2O5 Doping on the Microstructure and Dielectric Properties of BaTiO3 Based Ceramics
Authors: Mousharraf Adnan , Islam Md. Fakhrul 
Published: June 2014

The main focus of the research was to correlate composition and sintering parameters with the microstructure and dielectric properties of Ta2O5 doped BaTiO3 ceramics. The samples were sintered using both single and two-stage sintering techniques. Thereafter SEM and XRD techniques were used to examine the structure of the samples with a particular focus on the incorporation of Ta5+ ions into the BaTiO3 crystal lattice. The SEM analysis focused on measuring the grain size and investigating the grain size distribution of the sintered samples. Finally, the dielectric properties were analysed and the relationship between the properties and structure of the doped BaTiO3 was established. From the research it can be stated that two-stage sintering yielded the best dielectric properties. The best stable value of the room temperature dielectric constant (k) of 19000 was obtained for the 1.5 mole % Ta2O5 doped BaTiO3 sample sintered at 13200C for 0hrs and 12800C for 6hrs, due to the combination of a high percent theoretical density (%TD) and optimum grain size. At a temperature range of 300 to 600C, this combination of composition and sintering parameters yielded a dielectric constant in the range of 18000–19000.
Nucleoporin FG Domains Facilitate mRNP Remodeling at the Cytoplasmic Face of the Nuclear Pore Complex
Authors: Adams Rebecca L , Terry Laura J , Wente Susan R 
Published: June 2014

Abstract
Directional export of messenger RNA (mRNA) protein particles (mRNPs) through nuclear pore complexes (NPCs) requires multiple factors. In Saccharomyces cerevisiae, the NPC proteins Nup159 and Nup42 are asymmetrically localized to the cytoplasmic face and have distinct functional domains: a phenylalanine-glycine (FG) repeat domain that docks mRNP transport receptors and domains that bind the DEAD-box ATPase Dbp5 and its activating cofactor Gle1, respectively. We speculated that the Nup42 and Nup159 FG domains play a role in positioning mRNPs for the terminal mRNP-remodeling steps carried out by Dbp5. Here we find that deletion (Δ) of both the Nup42 and Nup159 FG domains results in a cold-sensitive poly(A)+ mRNA export defect. The nup42ΔFG nup159ΔFG mutant also has synthetic lethal genetic interactions with dbp5 and gle1 mutants. RNA cross-linking experiments further indicate that the nup42ΔFG nup159ΔFG mutant has a reduced capacity for mRNP remodeling during export. To further analyze the role of these FG domains, we replaced the Nup159 or Nup42 FG domains with FG domains from other Nups. These FG “swaps” demonstrate that only certain FG domains are functional at the NPC cytoplasmic face. Strikingly, fusing the Nup42 FG domain to the carboxy-terminus of Gle1 bypasses the need for the endogenous Nup42 FG domain, highlighting the importance of proximal positioning for these factors. We conclude that the Nup42 and Nup159 FG domains target the mRNP to Gle1 and Dbp5 for mRNP remodeling at the NPC. Moreover, these results provide key evidence that character and context play a direct role in FG domain function and mRNA export.
Neuronal Remodeling During Metamorphosis Is Regulated by the alan shepard (shep) Gene in Drosophila melanogaster
Authors: Chen Dahong , Qu Chunjing , Bjorum Sonia M , Beckingham Kathleen M , Hewes Randall S 
Published: June 2014

Abstract
Peptidergic neurons are a group of neuronal cells that synthesize and secrete peptides to regulate a variety of biological processes. To identify genes controlling the development and function of peptidergic neurons, we conducted a screen of 545 splice-trap lines and identified 28 loci that drove expression in peptidergic neurons when crossed to a GFP reporter transgene. Among these lines, an insertion in the alan shepard (shep) gene drove expression specifically in most peptidergic neurons. shep transcripts and SHEP proteins were detected primarily and broadly in the central nervous system (CNS) in embryos, and this expression continued into the adult stage. Loss of shep resulted in late pupal lethality, reduced adult life span, wing expansion defects, uncoordinated adult locomotor activities, rejection of males by virgin females, and reduced neuropil area and reduced levels of multiple presynaptic markers throughout the adult CNS. Examination of the bursicon neurons in shep mutant pharate adults revealed smaller somata and fewer axonal branches and boutons, and all of these cellular phenotypes were fully rescued by expression of the most abundant wild-type shep isoform. In contrast to shep mutant animals at the pharate adult stage, shep mutant larvae displayed normal bursicon neuron morphologies. Similarly, shep mutant adults were uncoordinated and weak, while shep mutant larvae displayed largely, although not entirely, normal locomotor behavior. Thus, shep played an important role in the metamorphic development of many neurons.
Characterization of Localized Electrochemical Properties of Si3N4-TiC Ceramic Nanocomposite Using Dual-Electrode Scanning Probes
Authors: Liu Bernard Haochih , Cheng Jui-Teng 
Published: June 2014

ABSTRACTScanning probe microscopy, having the capability of nano-positioning and nanomanipulation, enables the characterization of material properties at a very small scale. In our previous work, the investigation of localized electrochemical reactions in Si3N4-TiC ceramic nanocomposites had been demonstrated using a single conductive scanning probe in a scanning impedance microscope (SIM). The results have provided experimental evidence that links the relations among microstructural heterogeneity, electrochemical property, and sintering behavior of spark plasma sintered ceramics. This single-probe SIM measurement gave through-body electrochemical information of specific surface feature of interest; however, the characterization of across-surface material properties in nanoscale is still much desired and unavailable.To further investigate the heterogeneity of materials, we have designed and developed a dual-electrode scanning probe (DESP), which is capable of localized electrochemical characterization across the surface of a material. These probes were designed based on computer simulation and iterations, and fabricated using common semiconductor processing techniques. The span of two probes (electrodes) in our first prototypes was 10∼15 microns, which can be further reduced with optimized parameters. The DESP probes have been evaluated on Si3N4-TiC nanocomposites to demonstrate their functionality in topography scanning and in-situ impedance measurement. The impedance spectroscopy revealed two distinct impedance patterns for measurements across TiC-rich and Si3N4-rich surface regions. The design, fabrication, and evaluation of DESP were discussed in addition to the analysis of Si3N4-TiC nanocomposites.
Reserves and Parameter Estimation using Rate-Transient and Decline Curve Analysis
Authors: Obe E. Akinlolu , Onyekonwu Mike O. 
Published: June 2014

Abstract
Traditional decline curve analysis enables estimation of reserves whilst pressure transient analysis enables the calculation well and reservoir parameters. The combination of both methods should enable the simultaneous estimation of reserves and well and reservoir parameters. However in the Niger delta, due to disruption of operations for a number of reasons, it is becoming increasing difficult to obtain required bottom hole pressure surveys for analytical purposes.
The paper’s objective is to design a methodology for obtaining reserves and reservoir/well parameters, with decline data and a minimum of BHP data. Combining rate-transient analysis with decline curve analysis allows us to attempt this.
In this paper, solutions of this combination have been applied to typical Niger Delta wells using Fetkovich, Blasingame and Agarwal-Gardner type curve. Satisfactory and reliable results comparable with the well-known and understood method of well test analysis were achieved. Furthermore, the author developed dimensionless type curves using available field data for the specific reservoirs, and for use in other wells.
From this work, it has been demonstrated that with the recent advancements in decline curve analysis, reliable results can be obtained, comparable to pressure transient analysis. Hence it should be increasingly attractive, especially in the Niger Delta, where BHP data is not current for many wells.