bluuebunny/crossref_metadata_2025 huggingface dataset:
“Zoom-In”—A Targeted Database Search for Identification of Glycation Modifications Analyzed by Untargeted Tandem Mass Spectrometry
Authors: Bhonsle Hemangi S. , Korwar Arvind M. , Kesavan Suresh K. , Bhosale Santosh D. , Bansode Sneha B. , Kulkarni Mahesh J.
Published: February 2013

Post-translational modifications (PTMs) are very important to biological function, however their identification and characterization is technically challenging. In this study, we have identified glycation modifications by nano LC-MSE, a data independent acquisition work flow, followed by database search using the Protein Lynx Global Server (PLGS). PLGS search with a complete human protein database hardly identified glycation modifications in a glycated human serum albumin (HSA), which was detected to be glycated by western blotting with advanced glycation end products (AGE) antibody and fluorescence spectroscopy. To overcome this difficulty, “Zoom-In” approach, a targeted database search was used to identify glycation modifications in a glycated HSA, which were further manually validated. This approach was useful for identification of glycation modifications from untargeted tandem mass spectrometry workflow such as MSE, but may require the development of a new algorithm or an upgrade of the existing software.
Vibration Control of Vehicle Seat Integrating with Chassis Suspension and Driver Body Model
Authors: Du Haiping , Li Weihua , Zhang Nong
Published: February 2013

Vehicle seat suspension is one of very important components to provide ride comfort, in particular, commercial vehicles, to reduce driver fatigue due to long hours driving. This paper presents a study on active control of seat suspension to reduce vertical vibration transmitted from uneven road profile to driver body. The control problem will be firstly studied by proposing an integrated seat suspension model which includes vehicle chassis suspension, seat suspension, and driver body model. This is a new concept in the field of study because most of the current active and semi-active seat suspension studies only consider seat suspension or seat suspension with human body model, and road disturbance is generally assumed to be applied to the cabin floor directly. Controller design based an integrated model will enable the seat suspension to perform in a scenario where vibration caused by road disturbance is transmitted from wheel to seat frame and ride comfort performance is evaluated in terms of human body instead of seat frame acceleration. A static output feedback controller is then designed for the seat suspension with using measurement available signals. Driver mass variation and actuator saturation are also considered in the controller design process. The conditions for designing such a controller are derived in terms of linear matrix inequalities (LMIs). Finally, numerical simulations are used to validate the effectiveness of the proposed control strategy. It is shown from the driver body acceleration responses under both bump and random road disturbances that the newly designed seat suspension can improve vehicle ride comfort regardless of driver body mass variation.
Modal Power Flow Analysis of a Damaged Orthotropic Plate
Authors: Wong Waion , Cheung Yanlung , Cheng Li
Published: February 2013

The effect of the change of structural integrity to the change of the reactive power flow of a vibrating structure at resonance is explored both analytically and numerically. When an undamped structure undergoes free vibration at one of its natural frequencies, the reactive component is of modal pattern and it can be used as a new modal signature. The reactive power flow in this case can thus be termed as modal power flow. The instantaneous energy density associated with the vibration mode consists of a static component and a dynamic component, related to the mean total and Lagrangian energy densities, respectively. The modal power flow is relevant to the latter but independent of the former. The inverse problem of detecting structural damage due to the identification of variation of modal power flow pattern is investigated. Modal power flow of an orthotropic composite plate with a region of reduced stiffness in the plate is analyzed. Numerical tests show that the proposed method is effective for detection of the damage and the modal power flow is more sensitive to the change of plate stiffness than the strain mode shape in the test cases.
State Estimation and Joint Actuator Fault Reconstruction for Planar One-Legged Articulated Hopping Robots Using an Extended Kalman Filter Approach
Authors: Pan Shuwen , Shi Mengjia , Liu Zhitao , Zhang Ju
Published: February 2013

When joint actuator faults of the legged robot systems occur, it is important to estimate the states and unknown faults (inputs) accurately for the emergent operation of the control system to protect the robot per se and the surrounding environment. The traditional extended Kalman filter (EKF) is a routine method for state estimation, however, it requires that all the input data are measured. In this paper, an extended Kalman filter with fault reconstruction, referred to as EKF-FR, is proposed to estimate the states as well as unknown joint actuator faults (inputs) for the planar one-legged articulated hopping robot system, which owns the fundamental dynamic characteristics for advanced legged robots. The major merit of the proposed EKF-FR approach lies in the fact that the unknown faults (inputs) are reconstructed by designing an input-output linearization controller with asymptotical stability based on the nonlinear robot system, hence the proposed approach is with more accuracy in comparison with the ones based on the Jacobian linearized systems, such as the extended Kalman filter with unknown inputs (EKF-UI). Simulation results for two single-fault cases demonstrate the effectiveness of the proposed EKF-FR algorithm.
Effectiveness of “Detuned” TMD's for Beam-Like Footbridges
Authors: Werkle Horst , Butz Christiane , Tatar Roxana
Published: February 2013

The dynamic properties of Tuned Mass Dampers (TMD's) used to reduce the vibrations of footbridges are generally based on the optimization criterion of Den Hartog. However the spring, mass and damper of a TMD may possess slight fabrication tolerances or change its damping element properties due to temperature, which can result in a detuning of a TMD. The study presented deals with the influence of a detuning on the performance of a TMD. A simplified model for beam-like footbridges under pedestrian loading is proposed. It is shown that a 2-DOF-system in harmonic stationary motion represents a good approximation of the beam structure under transient time-dependent load. Graphs are given to assess the increase of acceleration and the decrease of effectiveness due to detuning. A case study on a footbridge with a span of 45 m demonstrates its accuracy.
Two-Step Method for Instability Damage Detection in Tower Body of Transmission Structures
Authors: Qu Weilian , Song Wanjun , Xia Yong , Xu Youlin , Qin Wenke , Jiang Zhicai
Published: February 2013

Instability damage may occur in some members of the transmission tower subjected to the downburst, and eventually the damage accumulation may further lead to the failure of the tower. Therefore, it is extremely essential to identify and repair the damaged major vertical members in tower body timely. The relationship surface of instable member among axial compression force, bending moment at the end and axial stiffness is determined. The results show that the axial stiffness of the instability members reduces to zero gradually. Accordingly, a two-step detection method of the major vertical member instability damage is presented. The first step detection is used to find the possible buckling damaged regions by using wavelet packet energy curvature change rate index. The second step is used to identify location of buckling damaged major member that appears in the possible damaged subregions based on the theory of modal strain energy and interval estimation. Finally, the proposed method is applied to a realistic transmission tower and experimental verified with a steel tube tower. The results indicate that the two-step detection method is effective and feasible.
FEM Calibrated ARMAX Model Updating Method for Time Domain Damage Identification
Authors: Wang Ying , Khoo Suiyang , Li An-Jui , Hao Hong
Published: February 2013

Due to environmental loads, mechanical damages, structural aging and human factors, civil infrastructure inevitably deteriorate during their service lives. Since their damage may claim human lives and cause significant economic losses, how to identify damages and assess structural conditions timely and accurately has drawn increasingly more attentions from structural engineering community worldwide. In this study, a fast and sensitive time domain damage identification method will be developed. To do this, a finite element model of a steel pipe laid on the soil is built and the structural responses are simulated under different damage scenarios. Based on the simulated data, an Auto Regressive Moving Average Exogenous (ARMAX) model is then built and calibrated. The calibrated ARMAX model is used to identify different damage scenarios through model updating process using clonal selection algorithm (CSA). The results demonstrate the application potential of the proposed method in identifying the pipeline conditions. To further verify its performance, laboratory tests of a steel pipe laid on the soil with and without soil support (free span damage) are carried out. The identification results of pipe-soil system show that the proposed method is capable of identifying damagein a complex structural system. Therefore, it can be applied to identifying pipeline conditions.
Wheel-Set Hunting Movement and its Contribution to Coupling Vibration of Vehicle-Bridge System
Authors: Cheng Q. , Zhang N. , Xia H. , Zhang T. , Du X.T.
Published: February 2013

Wheel-set hunting is an important and random lateral movement when wheel-set running on the track. Firstly a vehicle-bridge dynamic interaction model is established, in which the lateral wheel-rail interaction is defined by Kalker linear creep theory with the calculation of detailed wheel-rail contact adhesion geometric parameters and creep force. Then with the case of a high speed train passing a 32 m simply-supported beam bridge, the wheel-set hunting movement is calculated according to the relative vehicle and bridge lateral movement. And the characteristics of wheel-set hunting with different train speed and bridge stiffness are discussed. Then a simple lateral wheel-rail interaction is defined with close contact and no elastic deformation, and the contribution of hunting movement to coupling vibration of vehicle-bridge system is summarized in this method. The results show that the wheel-set hunting movement could be neglected when analyzing the bridge response, but it should be considered when analyzing the vehicle response in the vehicle-bridge interaction.
Nanoscale processes simulated by transforms and image processing methods
Authors: Mirchin N. , Peled A. , Azoulay J.
Published: February 2013

A simulation method was developed to display images of nano-particles and their dynamic 2D growth on surfaces, due to mechanisms such as adsorption, diffusion and coalescence. In this method a mathematical Fourier frequency tranforms (FT) of a 2D image density functions representing the nanostructure and image processing are combined to obtain a continuos visualization of thin film depositon process. These images are then convoluted using FT of spatiotemporal integrodifferential equations involving the physical driving forces models in the frequency domain. Using an appropriate prediction models we were able to solve the spatiotemporal evolutional equations. Thus the surface growth and restructuring effects taking place during the photo-deposition processes were investigated. In particular, the dynamic changes of the photo-deposited nanoparticles morphology during sub-monolayer growth were simulated. The simulation and scanning electron microscopy (SEM) micrographs of a-Se photo deposited thin films during monolayer formation were discuussed and were found to be good accordance and complementary.
Overexpression of initiator methionine tRNA leads to global reprogramming of tRNA expression and increased proliferation in human epithelial cells
Authors: Pavon-Eternod Mariana , Gomes Suzana , Rosner Marsha R. , Pan Tao
Published: February 2013

Transfer RNAs (tRNAs) are typically considered housekeeping products with little regulatory function. However, several studies over the past 10 years have linked tRNA misregulation to cancer. We have previously reported that tRNA levels are significantly elevated in breast cancer and multiple myeloma cells. To further investigate the cellular and physiological effects of tRNA overexpression, we overexpressed tRNAiMet in two human breast epithelial cell lines. We then determined tRNA abundance changes and performed phenotypic characterization. Overexpression of tRNAiMet significantly altered the global tRNA expression profile and resulted in increased cell metabolic activity and cell proliferation. Our results extend the relevance of tRNA overexpression in human cells and underscore the complexity of cellular regulation of tRNA expression.
Use of Aerosolized Tissue Plasminogen Activator in the Treatment of Plastic Bronchitis
Authors: Lubcke Nicole L , Nussbaum Vicki M , Schroth Mary
Published: February 2013

OBJECTIVE

To present a case of nebulized tissue plasminogen activator (t-PA) treatment for symptomatic plastic bronchitis in a pediatric patient years after a Fontan procedure.

CASE SUMMARY

A 13-year-old boy with a history of corrected congenital heart disease was admitted to the pediatric intensive care unit after 2 weeks of worsening respiratory distress. A chest radiograph and subsequent bronchoscopy revealed extensive mucus plugging due to plastic bronchitis. Casts reaccumulated quickly after manual removal of the mucus and a regimen of aerosolized t-PA was initiated to break down the casts and prevent further cast formation over the 17-day hospital course. The treatment was successful and the patient was discharged home without evidence of bronchial casts.

DISCUSSION

Plastic bronchitis is a potentially devastating condition in which pulmonary infiltrates line the bronchial tree, forming casts and prohibiting effective oxygen exchange. There are few effective treatment options for this condition. The use of aerosolized t-PA for the treatment of plastic bronchitis has been reported to be safe and effective in 4 cases but no consistent regimen, dose, or duration of treatment has been established.

CONCLUSIONS

t-PA can be nebulized and inhaled for successful inhibition of bronchial cast formation. More information to determine the most effective dose and duration of therapy is needed to effectively improve the lives of people with plastic bronchitis.
A fractional Yamabe flow and some applications
Authors: Jin Tianling , Xiong Jingang
Published: February 2013

We introduce a fractional Yamabe flow involving nonlocal conformally invariant operators on the conformal infinity of asymptotically hyperbolic manifolds, and show that on the conformal spheres

(

𝕊
n

,

[

g

𝕊
n

]

)

$(\mathbb {S}^n,[g_{\mathbb {S}^n}])$

, it converges to the standard sphere up to a Möbius diffeomorphism. These arguments can be applied to obtain extinction profiles of solutions of some fractional porous medium equations.
In the end, we use this fractional fast diffusion equation, together with its extinction profile and some estimates of its extinction time, to improve a Sobolev inequality via a quantitative estimate of the remainder term.
Synthesis and chemistry of structurally unique hexasubstituted pyrazolines
Authors: Baumstark Alfons L. , Vasquez Pedro C. , McTush-Camp Davita
Published: February 2013

A review focused on our contributions to the synthesis and chemistry of hexasubstituted pyrazolines is presented. The development of a synthetic route to pentasubstituted 2H-pyrazoles 1 provides the key starting materials that are used in the synthesis of several unique series of highly substituted pyrazolines 2–6. Thermolysis of pyrazolines 2–4 allows the facile synthesis of hexasubstituted cyclopropanes. Autoxidation of pentasubstituted 2H-pyrazoles 1 in acetone produces a series of hydroperoxy substituted pyrazolines 5 which are effective oxygen-atom transfer reagents. The thermal decomposition of 5 produces β-keto radicals, the transformation of which in the presence of oxygen provides a good route for the synthesis of 3-hydroxy-1,2-dioxolanes. The reaction of tosyl chloride with a pentasubstituted 2H-pyrazole yields a chloro-substituted pyrazoline 6 rather than the expected N-tosyl product. Thermolysis of 6 yields products, the structure of which is consistent with the formation of an unstable intermediate chloro-substituted cyclopropane.
Unique continuation and continuous dependence results for a severely ill-posed integrodifferential parabolic problem with a memory term in the principal part of the differential operator
Authors: Lorenzi Alfredo , Messina Francesca
Published: February 2013

We prove uniqueness and continuous dependence results for a severely ill-posed linear integrodifferential
boundary-value parabolic problem with no initial condition. This latter condition is replaced with an additional
boundary information prescribing the temperature on an open subset of the geometric domain .

The integral operators entering the equation are defined by integrals of Volterra type with respect to time. In particular, the class of integrodifferential equations dealt with in this paper include those occurring in the linear
theory of heat flow in a rigid body consisting of a material with thermal memory.
Dexras1, a Small GTPase, Is Required for Glutamate-NMDA Neurotoxicity
Authors: Chen Yong , Khan Reas S. , Cwanger Alyssa , Song Ying , Steenstra Catherine , Bang Sookhee , Cheah Jaime H. , Dunaief Joshua , Shindler Kenneth S. , Snyder Solomon H. , Kim Sangwon F.
Published: February 2013

Dexras1, a small G-protein localized predominantly to the brain, is transcriptionally upregulated by the synthetic glucocorticoid dexamethasone. It has close homology to the Ras subfamily but differs in that Dexras1 contains an extended 7 kDa C-terminal tail. Previous studies in our laboratory showed that NMDA receptor activation, via NO and Dexras1, physiologically stimulates DMT1, the major iron importer. A membrane-permeable iron chelator substantially reduces NMDA excitotoxicity, suggesting that Dexras1-mediated iron influx plays a crucial role in NMDA/NO-mediated cell death. We here report that iron influx is elicited by nitric oxide but not by other proapoptotic stimuli, such as H2O2or staurosporine. Deletion of Dexras1 in mice attenuates NO-mediated cell death in dissociated primary cortical neurons and retinal ganglion cellsin vivo. Thus, Dexras1 appears to mediate NMDA-elicited neurotoxicity via NO and iron influx.
CCAAT Enhancer Binding Protein δ Plays an Essential Role in Memory Consolidation and Reconsolidation
Authors: Arguello Amy A. , Ye Xiaojing , Bozdagi Ozlem , Pollonini Gabriella , Tronel Sophie , Bambah-Mukku Dhananjay , Huntley George W. , Platano Daniela , Alberini Cristina M.
Published: February 2013

A newly formed memory is temporarily fragile and becomes stable through a process known as consolidation. Stable memories may again become fragile if retrieved or reactivated, and undergo a process of reconsolidation to persist and strengthen. Both consolidation and reconsolidation require an initial phase of transcription and translation that lasts for several hours. The identification of the critical players of this gene expression is key for understanding long-term memory formation and persistence. In rats, the consolidation of inhibitory avoidance (IA) memory requires gene expression in both the hippocampus and amygdala, two brain regions that process contextual/spatial and emotional information, respectively; IA reconsolidation requiresde novogene expression in the amygdala. Here we report that, after IA learning, the levels of the transcription factor CCAAT enhancer binding protein δ (C/EBPδ) are significantly increased in both the hippocampus and amygdala. These increases are essential for long-term memory consolidation, as their blockade via antisense oligodeoxynucleotide-mediated knockdown leads to memory impairment. Furthermore, C/EBPδ is upregulated and required in the amygdala for IA memory reconsolidation. C/EBPδ is found in nuclear, somatic, and dendritic compartments, and a dendritic localization of C/EBPδ mRNA in hippocampal neuronal cultures suggests that this transcription factor may be translated at synapses. Finally, the induction of long-term potentiation at CA3-CA1 synapses by tetanic stimuli in acute slices, a cellular model of long-term memory, leads to an accumulation of C/EBPδ in the nucleus. We conclude that the transcription factor C/EBPδ plays a critical role in memory consolidation and reconsolidation.
P2X7 Receptor Channels Allow Direct Permeation of Nanometer-Sized Dyes
Authors: Browne Liam E. , Compan Vincent , Bragg Laricia , North R. Alan
Published: February 2013

P2X receptors are widely distributed in the nervous system, and P2X7 receptors have roles in neuropathic pain and in the release of cytokines from microglia. They are trimeric membrane proteins, which open an integral ion channel when ligated by extracellular ATP. This channel is preferentially permeable to small cations (sodium, potassium, calcium) but also allows permeation of larger cations such asN-methyl-d-glucamine. ATP also leads to entry of fluorescent dyes in many cells expressing P2X7 receptors, but controversy persists as to whether such large molecules pass directly through the open ion channel or enter the cell by a different route. We measured cellular fluorescence and membrane currents in individual human embryonic kidney cells expressing rat P2X7 receptors. Introduction of positive side chains by mutagenesis into the inner half of the pore-forming second transmembrane domain of the receptor (T348K, D352N, D352K) increased relative permeability of chloride ions. It also promoted entry of the large (>1 nm) negative dye fluorescein-5-isothiocyanate while decreasing entry of the structurally similar but positive dye ethidium. Furthermore, larger cysteine-reactive methanethiosulfonates [sulforhodamine-methanethiosulfonate and 2-((biotinoyl)amino)ethyl methanethiosulfonate] reduced both ATP-evoked currents and dye entry when applied to open P2X7[G345C] receptors. The results demonstrate that the open channel of the P2X7 receptor can allow passage of molecules with sizes up to 1.4 nm.
Serotonin Modulates Striatal Responses to Fairness and Retaliation in Humans
Authors: Crockett Molly J. , Apergis-Schoute Annemieke , Herrmann Benedikt , Lieberman Matthew D. , Müller Ulrich , Robbins Trevor W. , Clark Luke
Published: February 2013

Humans are willing to incur personal costs to punish others who violate social norms. Such “costly punishment” is an important force for sustaining human cooperation, but the causal neurobiological determinants of punishment decisions remain unclear. Using a combination of behavioral, pharmacological, and neuroimaging techniques, we show that manipulating the serotonin system in humans alters costly punishment decisions by modulating responses to fairness and retaliation in the striatum. Following dietary depletion of the serotonin precursor tryptophan, participants were more likely to punish those who treated them unfairly, and were slower to accept fair exchanges. Neuroimaging data revealed activations in the ventral and dorsal striatum that were associated with fairness and punishment, respectively. Depletion simultaneously reduced ventral striatal responses to fairness and increased dorsal striatal responses during punishment, an effect that predicted its influence on punishment behavior. Finally, we provide behavioral evidence that serotonin modulates specific retaliation, rather than general norm enforcement: depleted participants were more likely to punish unfair behavior directed toward themselves, but not unfair behavior directed toward others. Our findings demonstrate that serotonin modulates social value processing in the striatum, producing context-dependent effects on social behavior.
Phosphorylation and Feedback Regulation of Metabotropic Glutamate Receptor 1 by Calcium/Calmodulin-Dependent Protein Kinase II
Authors: Jin Dao-Zhong , Guo Ming-Lei , Xue Bing , Fibuch Eugene E. , Choe Eun Sang , Mao Li-Min , Wang John Q.
Published: February 2013

The metabotropic glutamate receptor 1 (mGluR1) is a Gαq-protein-coupled receptor and is distributed in broad regions of the mammalian brain. As a key element in excitatory synaptic transmission, the receptor regulates a wide range of cellular and synaptic activities. In addition to regulating its targets, the receptor itself is believed to be actively regulated by intracellular signals, although underlying mechanisms are essentially unknown. Here we found that a synapse-enriched protein kinase, Ca2+/calmodulin-dependent protein kinase IIα (CaMKIIα), directly binds to the intracellular C terminus (CT) of mGluR1a. This binding is augmented by Ca2+in vitro. The direct interaction promotes CaMKIIα to phosphorylate mGluR1a at a specific threonine site (T871). In rat striatal neurons, the mGluR1 agonist triggers the receptor-associated phosphoinositide signaling pathway to induce Ca2+-dependent recruitment of CaMKIIα to mGluR1a–CT. This enables the kinase to inhibit the response of the receptor to subsequent agonist exposure. Our data identify an agonist-induced and Ca2+-dependent protein–protein interaction between a synaptic kinase and mGluR1, which constitutes a feedback loop facilitating desensitization of mGluR1a.
Parietal Oscillations Code Nonvisual Reach Targets Relative to Gaze and Body
Authors: Buchholz Verena N. , Jensen Ole , Medendorp W. Pieter
Published: February 2013

Recent blood oxygenation level-dependent (BOLD) imaging work has suggested flexible coding frames for reach targets in human posterior parietal cortex, with a gaze-centered reference frame for visually guided reaches and a body-centered frame for proprioceptive reaches. However, BOLD activity, which reflects overall population activity, is insensitive to heterogeneous responses at the neuronal level and temporal dynamics between neurons. Neurons could synchronize in different frequency bands to form assemblies operating in different reference frames. Here we assessed the reference frames of oscillatory activity in parietal cortex during reach planning to nonvisible tactile stimuli. Under continuous recording of magneto-encephalographic data, subjects fixated either to the left or right of the body midline, while a tactile stimulus was presented to a nonvisible fingertip, located either to the left or right of gaze. After a delay, they had to reach toward the remembered stimulus location with the other hand. Our results show body-centered and gaze-centered reference frames underlying the power modulations in specific frequency bands. Whereas beta-band activity (18–30 Hz) in parietal regions showed body-centered spatial selectivity, the high gamma band (>60 Hz) demonstrated a transient remapping into gaze-centered coordinates in parietal and extrastriate visual areas. This gaze-centered coding was sustained in the low gamma (<60 Hz) and alpha (∼10 Hz) bands. Our results show that oscillating subpopulations encode remembered tactile targets for reaches relative to gaze, even though neither the sensory nor the motor output processes operate in this frame. We discuss these findings in the light of flexible control mechanisms across modalities and effectors.
Locus Coeruleus Stimulation Recruits a Broad Cortical Neuronal Network and Increases Cortical Perfusion
Authors: Toussay Xavier , Basu Kaustuv , Lacoste Baptiste , Hamel Edith
Published: February 2013

The locus coeruleus (LC), the main source of brain noradrenalin (NA), modulates cortical activity, cerebral blood flow (CBF), glucose metabolism, and blood–brain barrier permeability. However, the role of the LC–NA system in the regulation of cortical CBF has remained elusive. This rat study shows that similar proportions (∼20%) of cortical pyramidal cells and GABA interneurons are contacted by LC–NA afferents on their cell soma or proximal dendrites. LC stimulation induced ipsilateral activation (c-Fos upregulation) of pyramidal cells and of a larger proportion (>36%) of interneurons that colocalize parvalbumin, somatostatin, or nitric oxide synthase compared with pyramidal cells expressing cyclooxygenase-2 (22%,p< 0.05) or vasoactive intestinal polypeptide-containing interneurons (16%,p< 0.01). Concurrently, LC stimulation elicited larger ipsilateral compared with contralateral increases in cortical CBF (52 vs 31%,p< 0.01). These CBF responses were almost abolished (−70%,p< 0.001) by cortical NA denervation with DSP-4 [N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride] and were significantly reduced by α- and β-adrenoceptor antagonists (−40%,p< 0.001 and −30%,p< 0.05, respectively). Blockade of glutamatergic or GABAergic neurotransmission with NMDA or GABAAreceptor antagonists potently reduced the LC-induced hyperemic response (−56%,p< 0.001 or −47%,p< 0.05). Moreover, inhibition of astroglial metabolism (−35%,p< 0.01), vasoactive epoxyeicosatrienoic acids (EETs; −60%,p< 0.001) synthesis, large-conductance, calcium-operated (BK, −52%,p< 0.05), and inward-rectifier (Kir, −40%,p< 0.05) K+channels primarily impaired the hyperemic response. The data demonstrate that LC stimulation recruits a broad network of cortical excitatory and inhibitory neurons resulting in increased cortical activity and that K+fluxes and EET signaling mediate a large part of the hemodynamic response.
Histone-Methyltransferase MLL2 (KMT2B) Is Required for Memory Formation in Mice
Authors: Kerimoglu Cemil , Agis-Balboa Roberto C. , Kranz Andrea , Stilling Roman , Bahari-Javan Sanaz , Benito-Garagorri Eva , Halder Rashi , Burkhardt Susanne , Stewart Adrian Francis , Fischer Andre
Published: February 2013

The consolidation of long-term memories requires differential gene expression. Recent research has suggested that dynamic changes in chromatin structure play a role in regulating the gene expression program linked to memory formation. The contribution of histone methylation, an important regulatory mechanism of chromatin plasticity that is mediated by the counteracting activity of histone-methyltransferases and histone-demethylases, is, however, not well understood. Here we show that mice lacking the histone-methyltransferase myeloid/lymphoid or mixed-lineage leukemia 2 (mll2/kmt2b) gene in adult forebrain excitatory neurons display impaired hippocampus-dependent memory function. Consistent with the role of KMT2B in gene-activation DNA microarray analysis revealed that 152 genes were downregulated in the hippocampal dentate gyrus region of mice lackingkmt2b. Downregulated plasticity genes showed a specific deficit in histone 3 lysine 4 di- and trimethylation, while histone 3 lysine 4 monomethylation was not affected. Our data demonstrates that KMT2B mediates hippocampal histone 3 lysine 4 di- and trimethylation and is a critical player for memory formation.
Dendritic End Inhibition in Large-Field Visual Neurons of the Fly
Authors: Elyada Yishai M. , Haag Juergen , Borst Alexander
Published: February 2013

The extraction of optic flow fields by visual systems is crucial for course stabilization during locomotion, and relies on feedforward and lateral integration of visual inputs. Here we report a novel form of systemic, motion-sensitive lateral suppression in the dendrites of large, flow-field-selective neurons in the fly's visual lobes. Usingin vivoCalcium-imaging and intracellular recordings, we demonstrate that responses in dendrites, but not axon terminals, are end inhibited by flanking gratings both in the vertical and horizontal systems. We show evidence for a mechanism involving wide-field dendritic inhibition that exceeds the retinotopic spatial extent of the dendrites. Using compartmental modeling, we point out a possible function in enhancing selectivity for optic flow fields. Our results suggest that lateral suppression is a common element serving similar functional requirements in different visual systems.
Temporal Evolution of Pattern Disparity Processing in Humans
Authors: Quaia Christian , Sheliga Boris M. , Optican Lance M. , Cumming Bruce G.
Published: February 2013

Stereo matching, i.e., the matching by the visual system of corresponding parts of the images seen by the two eyes, is inherently a 2D problem. To gain insights into how this operation is carried out by the visual system, we measured, in human subjects, the reflexive vergence eye movements elicited by the sudden presentation of stereo plaids. We found compelling evidence that the 2D pattern disparity is computed by combining disparities first extracted within orientation selective channels. This neural computation takes 10–15 ms, and is carried out even when subjects perceive not a single plaid but rather two gratings in different depth planes (transparency). However, we found that 1D disparities are not always effectively combined: When spatial frequency and contrast of the gratings are sufficiently different pattern disparity is not computed, a result that cannot be simply attributed to the transparency of such stimuli. Based on our results, we propose that a narrow-band implementation of the IOC (Intersection of Constraints) rule (Fennema and Thompson, 1979; Adelson and Movshon, 1982), preceded by cross-orientation suppression, underlies the extraction of pattern disparity.
Emergence of Population Bursts from Simultaneous Activation of Small Subsets of preBötzinger Complex Inspiratory Neurons
Authors: Kam Kaiwen , Worrell Jason W. , Ventalon Cathie , Emiliani Valentina , Feldman Jack L.
Published: February 2013

During rhythmic movements, central pattern generators (CPGs) trigger bursts of motor activity with precise timing. However, the number of neurons that must be activated within CPGs to generate motor output is unknown. In the mammalian breathing rhythm, a fundamentally important motor behavior, the preBötzinger Complex (preBötC) produces synchronous population-wide bursts of activity to control inspiratory movements. We probed mechanisms underlying inspiratory burst generation in the preBötC using holographic photolysis of caged glutamate in medullary slices from neonatal mice. With stimulation parameters determined to confine photoactivation to targeted neurons, simultaneous excitation of 4–9 targeted neurons could initiate ectopic, endogenous-like bursts with delays averaging 255 ms, placing a critical and novel boundary condition on the microcircuit underlying respiratory rhythmogenesis.
Spontaneous Optic Nerve Compression in the Osteopetrotic (op/op) Mouse: A Novel Model of Myelination Failure
Authors: Kondo Yoichi , Ramaker Jenna M. , Radcliff Abigail B. , Baldassari Simona , Mayer Joshua A. , Ver Hoeve James N. , Zhang Chuan-Li , Chiu Shing-Yan , Colello Raymond J. , Duncan Ian D.
Published: February 2013

We report a focal disturbance in myelination of the optic nerve in the osteopetrotic (op/op) mouse, which results from a spontaneous compression of the nerve resulting from stenosis of the optic canal. The growth of theop/opoptic nerve was significantly affected, being maximally suppressed at postnatal day 30 (P30; 33% of age matched control). Myelination of the nerve in the optic canal was significantly delayed at P15, and myelin was almost completely absent at P30. The size of nerves and myelination were conserved both in the intracranial and intraorbital segments at P30, suggesting that the axons in the compressed site are spared in all animals at P30. Interestingly, we observed recovery both in the nerve size and the density of myelinated axons at 7 months in almost half of the optic nerves examined, although some nerves lost axons and became atrophic.In vivoandex vivoelectrophysiological examinations of P30op/opmice showed that nerve conduction was significantly delayed but not blocked with partial recovery in some mice by 7 months. Transcardial perfusion of FITC-labeled albumin suggested that local ischemia was at least in part the cause of this myelination failure. These results suggest that the primary abnormality is dysmyelination of the optic nerve in early development. This noninvasive model system will be a valuable tool to study the effects of nerve compression on the function and survival of oligodendrocyte progenitor cells/oligodendrocytes and axons and to explore the mechanism of redistribution of oligodendrocyte progenitor cells with compensatory myelination.
Natural and Drug Rewards Act on Common Neural Plasticity Mechanisms with ΔFosB as a Key Mediator
Authors: Pitchers Kyle K. , Vialou Vincent , Nestler Eric J. , Laviolette Steven R. , Lehman Michael N. , Coolen Lique M.
Published: February 2013

Drugs of abuse induce neuroplasticity in the natural reward pathway, specifically the nucleus accumbens (NAc), thereby causing development and expression of addictive behavior. Recent evidence suggests that natural rewards may cause similar changes in the NAc, suggesting that drugs may activate mechanisms of plasticity shared with natural rewards, and allowing for unique interplay between natural and drug rewards. In this study, we demonstrate that sexual experience in male rats when followed by short or prolonged periods of loss of sex reward causes enhanced amphetamine reward, indicated by sensitized conditioned place preference for low-dose (0.5 mg/kg) amphetamine. Moreover, the onset, but not the longer-term expression, of enhanced amphetamine reward was correlated with a transient increase in dendritic spines in the NAc. Next, a critical role for the transcription factor ΔFosB in sex experience-induced enhanced amphetamine reward and associated increases in dendritic spines on NAc neurons was established using viral vector gene transfer of the dominant-negative binding partner ΔJunD. Moreover, it was demonstrated that sexual experience-induced enhanced drug reward, ΔFosB, and spinogenesis are dependent on mating-induced dopamine D1 receptor activation in the NAc. Pharmacological blockade of D1 receptor, but not D2 receptor, in the NAc during sexual behavior attenuated ΔFosB induction and prevented increased spinogenesis and sensitized amphetamine reward. Together, these findings demonstrate that drugs of abuse and natural reward behaviors act on common molecular and cellular mechanisms of plasticity that control vulnerability to drug addiction, and that this increased vulnerability is mediated by ΔFosB and its downstream transcriptional targets.
Spatiotemporal Coordination of Slow-Wave Ongoing Activity across Auditory Cortical Areas
Authors: Farley Brandon J. , Noreña Arnaud J.
Published: February 2013

Natural acoustic stimuli contain slow temporal fluctuations, and the modulation of ongoing slow-wave activity by bottom-up and top-down factors plays essential roles in auditory cortical processing. However, the spatiotemporal pattern of intrinsic slow-wave activity across the auditory cortical modality is unknown. Usingin vivovoltage-sensitive dye imaging in anesthetized guinea pigs, we measured spectral tuning to acoustic stimuli across several core and belt auditory cortical areas, and then recorded spontaneous activity across this defined network. We found that phase coherence in spontaneous slow-wave (delta-theta band) activity was highest between regions of core and belt areas that had similar frequency tuning, even if they were distant. Further, core and belt regions with high phase coherence were phase shifted. Interestingly, phase shifts observed during spontaneous activity paralleled latency differences for evoked activity. Our findings suggest that the circuits underlying this intrinsic source of slow-wave activity support coordinated changes in excitability between functionally matched but distributed regions of the auditory cortical network.
Electrolysis of Alcohols in High Temperature-High Pressure Water
Authors: Yuksel Asli , Sasaki Mitsuru , Goto Motonobu
Published: February 2013

The design of clean, efficient and environmentally friendly routes that reduce the waste production and fuel emissions of pollutants into the atmosphere, produce clean, affordable, and renewable energy sources to lessen energy consumption and toxicity on the environment, has become a central issue of chemical research both in industry and academia. One of the approaches being used in green chemistry practices is to use water as a solvent and reaction medium where possible. Much of this work deals with liquid water at temperatures exceeding the normal boiling point which is denoted as sub-critical water.

Electrochemical reaction, usually operated at atmospheric condition in water, is generally slow, although it has advantages over chemical reaction such as suppression of side reaction by tuning operating conditions. Since sub-critical water (7 MPa and 250 °C) has remarkable properties such as high ion product and low dielectric constant, it could be a suitable reaction media.

We have been studying electrolysis of organic compounds in sub-critical water as waste treatment and molecular degradation technologies. Electrolysis in sub-critical water could degrade harmful and thermally stable organic compounds into innocuous compounds such as hydrogen and water. In this research, we focused on the investigation of the electrochemical reactions of alcohols in sub-critical water to evaluate possibility for the selective production of hydrogen and value-added chemicals.

Electrochemical reactions were carried out in sub-critical water using a specially designed autoclave made of SS 316 with a volume of 500 mL. For comparison, thermal degradation experiments of alcohols were also conducted without any direct current loading at identical conditions. Here we employed glycerol and 1-butanol as model compounds of alcohols.

As a result of 1-butanol experiments, butanal and butyric acid were produced via partial oxidation at 250 °C and by applying 1-3 A of direct current while no oxidation products were observed at the hydrothermal degradation run. As a gaseous product, hydrogen gas was generated according to the electrochemical reaction mechanism. In the case of glycerol experiments, the main gaseous product was hydrogen gas, whereas glycolaldehyde, lactic acid, and formic acid were generated as the main liquid products at 280 °C. Results indicated that greater than 92% of the glycerol could be decomposed under optimum conditions by hydrothermal electrolysis technique.

This presented research will help to degrade stable organic materials in an environmentally friendly way and without need for secondary treatment processes. It will also address the need for novel more efficient techniques for the degradation of stable organic compounds in aqueous conditions and it will advance the use of water as a reaction medium in an efficient way without any organic solvent.
Fabrication of DLC-Based Micro-Gear Patterns by Room-Temperature Curing Nanoimprint Lithography Using Glass-Like Carbon Molds
Authors: Kiyohara Shuji , Ikegaki Tomu , Ito Chigaya , Ishikawa Ippei , Tanoue Hideto , Takikawa Hirofumi , Taguchi Yoshio , Sugiyama Yoshinari , Omata Yukiko , Kurashima Yuichi
Published: February 2013

The fabrication of diamond-like carbon (DLC) micro-gear by room temperature curing nanoimprint lithography (RTC-NIL) using glass-like carbon (GC) molds as applications to the DLC-based medical MEMS (Micro Electronic Mechanical Systems) was investigated. The DLC film which has excellent properties similar to chemical vapor deposited (CVD) diamond films was used as the patterning material. We propose GC as mold material because GC has higher etching selectivity than a diamond film. The etching selectivity of polysiloxane film against a GC substrate is about 5 times as high as that of a diamond film. Therefore we fabricated the GC molds that have micro-gear patterns with 30 µm-tip diameter and 500 nm-tooth thickness. We carried out the RTC-NIL process using the GC micro-gear molds under the following optimum conditions. 1 min-time from spin-coating to imprint: t1, 0.5 MPa-imprinting pressure: P and 5 min-holding time: t2, and then the imprinted polysiloxane pattern on DLC film was processed with an electron cyclotron resonance (ECR) oxygen ion shower. However, we were not able to fabricate micro-gear patterns in high accuracy because of a remaining residual layer on the DLC film. Therefore we propose the removing process for the residual layer with trifluoromethane (CHF3) ion shower under the optimum conditions of 300 eV-ion energy and 4 min-etching time. As a result, we succeeded to fabricate concave DLC-based micro-gear patterns in high accuracy which has 30 µm-tip diameter and 1 µm-depth.
Production of Silicon by Solid Oxide Membrane-Based Electrolysis Process
Authors: Jiang Yihong , Xu JiaPeng , Guan Xiaofei , Pal Uday B. , Basu Soumendra N.
Published: February 2013

The solid oxide membrane (SOM) electrolysis process has been successfully tested on a laboratory scale to produce silicon directly from silica in a cost-effective and eco-friendly way. A one-end-closed yttria-stabilized zirconia (YSZ) tube was employed to separate a molten salt containing dissolved silica from a liquid metal anode placed inside the YSZ tube. When an applied electric potential between a liquid tin cathode in the molten salt and the anode exceeds the dissociation potential of silica, oxygen ions are transported out of the molten salt through the YSZ membrane and oxidized at the anode while the silicon cations in the flux are reduced to silicon on the surface of the liquid tin cathode. A potentiodynamic scan (PDS) was performed to determine the dissociation potential of silica in the molten salt system. Electrolysis was performed at 1.05 V for 8 hours. The presence of high-purity silicon crystals on the surface of liquid tin cathode was confirmed by scanning electron microscopy (SEM) and electron dispersive X-ray spectroscopy (EDS).
Governança global e transferência de política: influências do Protocolo de Cartagena na Política Nacional de Biossegurança
Authors: Fontoura Yuna , Guedes Ana Lucia
Published: February 2013

No contexto de governança global, analisamos o tema da transferência de política, no qual a formulação de políticas públicas é influenciada por experiências de contextos políticos diferentes. Neste sentido, questionamos de que forma o Protocolo de Cartagena influenciou a formulação da Política Nacional de Biossegurança (PNB). A pesquisa empírica foi realizada por meio de entrevistas semiestruturadas com respondentes qualificados, que atuaram direta ou indiretamente na formulação da PNB. No tratamento dos dados adotamos uma abordagem qualitativa, por meio da utilização da análise de conteúdo. Os resultados revelam que houve transferência de política no formato de aprendizado (ou lesson drawing) do Protocolo de Cartagena à PNB.
O papel da Crabi no assentamento dos ribeirinhos atingidos pela construção da hidrelétrica de Salto Caxias no estado do Paraná
Authors: Derrosso Giuliano , Ichikawa Elisa Yoshie
Published: February 2013

Este artigo tem como objetivo discutir a forma com que o movimento social Comissão Regional dos Atingidos por Barragens do Rio Iguaçu (Crabi) atuou no assentamento dos sujeitos deslocados pela construção da hidrelétrica de Salto Caxias. Mediante entrevistas e dados secundários foi investigada a ampla participação da população neste movimento, o que se refletiu em melhores condições para o assentamento. O senso de luta coletiva fomentado pela criação e mobilização da Crabi permeou os processos de reconstrução da vida dos sujeitos deslocados pela Usina, e a efetiva participação deles fez com que fossem conquistadas melhores condições de enfrentamento da situação vivida.