Single Barrel Research Articles

ナノ電気化学セル顕微鏡を用いた電極表面の局所電気化学測定

Scanning electrochemical cell microscopy with a single barrel nanopipette (nanoSECCM), which is one of scanning electrochemical microscope (SECM) families, is a powerful tool for analyzing electrochemical activities (e.g. redox reaction and lithium-ion (de) intercalation processes) at localized area. A glass nano-pipette is used as a probe of nanoSECCM filled with electrolyte and a reference electrode. As the pipette is in proximity of sample surface, a meniscus is created. Through the meniscus, electrochemical activities can be obtained at localized area on the sample. Further, as the pipette scans the sample surface, electrochemical activities can be also visualized. Our experiments demonstrate that nanoSECCM is applicable to investigation of current response related to lithium-ion transport, redox cycling on various types of electrodes.

Test bench operation of a plasma fuelling device at IPR

A single barrel pellet injection system has been developed at Institute for plasma research (IPR). It is an in-situ pipe gun type injector, in which, a solid hydrogen pellet formed at freezing zone is accelerated to high speed by using high pressure propellant gas. The pellet injection system is equipped with a GM-cycle cryogenic refrigerator for pellet formation, a fast opening valve for pellet acceleration and diagnostic system to measure the ejected pellet parameter. A pellet is formed in-situ in the gun barrel connected to cryogenic refrigerator maintained at a temperature < 10 K. With proper thermal heat load minimization on cryo region, solid hydrogen pellets are obtained. In test bench operation various sized cylindrical pellets of dimension (length x diameter) 1.6 mm × 1.8 mm and 4 mm × 4.25 mm are produced. The ejected pellet speed is varied over a range from 700 to 1000 m/s by regulating propellant pressure. Whereas, the speed of a pellet is measured by time of flight based light gate diagnostic system, pellet quality and its size are estimated from fast camera imaging system. The reliability of pellet formation and injection in present experimental system is greater than 95%.

Investigations on the Wind Vibration Coefficient of Single Layer Lattice Barrel Vault Structures

Wind actions on the structures consist of two parts, the average action and the fluctuation action. The fluctuation action will cause the structures vibrating and enlarge the wind action of the structures. This paper investigates the wind vibration coefficient for the single layer lattice barrel vault structures. In the analysis, the simulation velocity-time curve of wind is developed and the finite element methods are used to analyze the wind-induced vibration responses of the lattice barrel vault structures. The influence of the rise to span ratio, the length to width ratio of the structure, and the different average velocity of the wind are investigated. Based on the numerical analysis results, the formula of the wind vibration coefficient for the single layer lattice barrel vault structure is suggested for the wind resistance design of the structures.

O-030 Preliminary French Registry Clinical Experience with the Barrel Bifurcation Vascular Reconstruction Device

Background/purposeEndovascular Stent-assisted coiling is a well establish technique for treatment of wide-necked intracranial aneurysms. However, it remains a challenge to successfully treat complex wide-necked bifurcate aneurysms by using a single-stent...

Functional significance of cortical NMDA receptors in somatosensory information processing

N-methyl-d-aspartate receptor (NMDAR)-mediated activity is required for whisker-related neural patterning in the rodent brain. Deletion of the essential NMDAR subunit NR1 gene in excitatory cortical neurons prevents whisker-specific barrel formation and impairs thalamocortical afferent patterning. We used electrophysiological and voltage-sensitive dye imaging methods to assess synaptic and sensory evoked cortical activity and immunohistochemistry to examine immediate early gene expression following whisker stimulation in cortex-specific NR1 knockout (CxNR1KO) mice. In mutant mice, layer IV neurons lacked NMDAR-mediated excitatory postsynaptic currents, and temporal summation of excitatory postsynaptic potentials (EPSPs) was impaired. Barrel neurons showed both phasic and tonic responses to whisker deflection. The averaged tonic response in CxNR1KO mice was significantly less than that in control mice due to impaired EPSP temporal summation. Electrophysiological estimation of the number of thalamic neurons innervating single barrel neurons indicated a significant increase in CxNR1KO mice. Similarly, voltage-sensitive dye optical signals in response to whisker stimulation were widespread. Immediate early gene expression following whisker stimulation also showed a diffuse expression pattern in the CxNR1KO cortex compared with whisker-specific expression patterns in controls. Thus, when NMDAR function is impaired, spatial discrimination of whisker inputs is severely compromised, and sensory stimulation evokes diffuse, topographically misaligned activity in the barrel cortex.

Genome sequence and functional genomic analysis of the oil-degrading bacterium Oleispira antarctica.

Ubiquitous bacteria from the genus Oleispira drive oil degradation in the largest environment on Earth, the cold and deep sea. Here we report the genome sequence of Oleispira antarctica and show that compared with Alcanivorax borkumensis—the paradigm of mesophilic hydrocarbonoclastic bacteria—O. antarctica has a larger genome that has witnessed massive gene-transfer events. We identify an array of alkane monooxygenases, osmoprotectants, siderophores and micronutrient-scavenging pathways. We also show that at low temperatures, the main protein-folding machine Cpn60 functions as a single heptameric barrel that uses larger proteins as substrates compared with the classical double-barrel structure observed at higher temperatures. With 11 protein crystal structures, we further report the largest set of structures from one psychrotolerant organism. The most common structural feature is an increased content of surface-exposed negatively charged residues compared to their mesophilic counterparts. Our findings are relevant in the context of microbial cold-adaptation mechanisms and the development of strategies for oil-spill mitigation in cold environments.

Direct Writing of Conducting Polymers

Described herein is a new printing method-direct writing of conducting polymers (CPs)-based on pipette-tip localized continuous electrochemical growth. A single barrel micropipette containing a metal wire (Pt) is filled with a mixture of monomer, supporting electrolyte, and an appropriate solvent. A droplet at the tip of the pipette contacts the substrate, which becomes the working electrode of a micro-electrochemical cell confined to the tip droplet and the pipette. The metallic wire in the pipette acts as both counter and reference electrode. Electropolymerization forms the CP on the working electrode in a pattern controlled by the movement of the pipette. In this study, various width poly(pyrrole) 2D and 3D structures are extruded and characterized in terms of microcyclic voltammetry, Raman spectroscopy, and scanning electron microscopy.

A Review of Newly Developed Firearms that can Fire Multiple Ammunition Types

Firearms have been able to fire multiple calibers and gauges of ammunition for years by means of multiple barrels, switching barrels, switching revolver cylinders, and in some cases firing a limited number of similar ammunition types through a single barrel and cylinder combination. Recently, however, several firearms have been made that can fire a wide variety of relatively dissimilar cartridges without multiple barrels or modifications to the firearm. The most prominent examples of these firearms include the Taurus Judge, the Smith &amp; Wesson 460XVR, and the Smith &amp; Wesson Governor. An awareness of the ability of certain types of firearms to fire multiple ammunition types can benefit a forensic pathologist's ability to interpret gunshot wounds.

Glancing angle deposition on a roll: Towards high-throughput nanostructured thin films

Increasing the throughput of the powerful single-step glancing angle deposition (GLAD) method using a prototype simplified roll-to-roll (R2R) system has been explored. While the conventional GLAD technique is popular for fabricating nanostructured devices in a single deposition step, it is not a high-output process. To evaluate the feasibility of large area GLAD deposition, the authors examined the geometrical considerations required to eventually achieve GLAD in a roll-to-roll manufacturing system. Nominal deposition and rotation angles were mathematically translated to their effective R2R counterparts, allowing for deposition recipes of the archetype GLAD nanostructures (slanted posts, vertical posts, and square spirals) and the mechanics of the phi-sweep technique to be converted to this space. Representative structures were then deposited, and the phi-sweep technique successfully applied, in a prototype single barrel roller R2R experimental system. This prototype system provides a foundation for moving GLAD from the laboratory to mass production.

Water Supply and Stormwater Management Benefits of Residential Rainwater Harvesting in U.S. Cities

AbstractThis article presents an analysis of the projected performance of urban residential rainwater harvesting systems in the United States (U.S.). The objectives are to quantify for 23 cities in seven climatic regions (1) water supply provided from rainwater harvested at a residential parcel and (2) stormwater runoff reduction from a residential drainage catchment. Water‐saving efficiency is determined using a water‐balance approach applied at a daily time step for a range of rainwater cistern sizes. The results show that performance is a function of cistern size and climatic pattern. A single rain barrel (190 l [50 gal]) installed at a residential parcel is able to provide approximately 50% water‐saving efficiency for the nonpotable indoor water demand scenario in cities of the East Coast, Southeast, Midwest, and Pacific Northwest, but &lt;30% water‐saving efficiency in cities of the Mountain West, Southwest, and most of California. Stormwater management benefits are quantified using the U.S. Environmental Protection Agency Storm Water Management Model. The results indicate that rainwater harvesting can reduce stormwater runoff volume up to 20% in semiarid regions, and less in regions receiving greater rainfall amounts for a long‐term simulation. Overall, the results suggest that U.S. cities and individual residents can benefit from implementing rainwater harvesting as a stormwater control measure and as an alternative source of water.

Manufacturing and Using Piggy-back Multibarrel Electrodes for &lt;em&gt;In vivo&lt;/em&gt; Pharmacological Manipulations of Neural Responses

In vivo recordings from single neurons allow an investigator to examine the firing properties of neurons, for example in response to sensory stimuli. Neurons typically receive multiple excitatory and inhibitory afferent and/or efferent inputs that integrate with each other, and the ultimate measured response properties of the neuron are driven by the neural integrations of these inputs. To study information processing in neural systems, it is necessary to understand the various inputs to a neuron or neural system, and the specific properties of these inputs. A powerful and technically relatively simple method to assess the functional role of certain inputs that a given neuron is receiving is to dynamically and reversibly suppress or eliminate these inputs, and measure the changes in the neuron's output caused by this manipulation. This can be accomplished by pharmacologically altering the neuron's immediate environment with piggy-back multibarrel electrodes. These electrodes consist of a single barrel recording electrode and a multibarrel drug electrode that can carry up to 4 different synaptic agonists or antagonists. The pharmacological agents can be applied iontophoretically at desired times during the experiment, allowing for time-controlled delivery and reversible reconfiguration of synaptic inputs. As such, pharmacological manipulation of the microenvironment represents a powerful and unparalleled method to test specific hypotheses about neural circuit function. Here we describe how piggy-back electrodes are manufactured, and how they are used during in vivo experiments. The piggy-back system allows an investigator to combine a single barrel recording electrode of any arbitrary property (resistance, tip size, shape etc) with a multibarrel drug electrode. This is a major advantage over standard multi-electrodes, where all barrels have more or less similar shapes and properties. Multibarrel electrodes were first introduced over 40 years ago 1-3, and have undergone a number of design improvements 2,3 until the piggy-back type was introduced in the 1980s 4,5. Here we present a set of important improvements in the laboratory production of piggy-back electrodes that allow for deep brain penetration in intact in vivo animal preparations due to a relatively thin electrode shaft that causes minimal damage. Furthermore these electrodes are characterized by low noise recordings, and have low resistance drug barrels for very effective iontophoresis of the desired pharmacological agents.

Manufacturing and Using Piggy-back Multibarrel Electrodes for &lt;em&gt;In vivo&lt;/em&gt; Pharmacological Manipulations of Neural Responses

In vivo recordings from single neurons allow an investigator to examine the firing properties of neurons, for example in response to sensory stimuli. Neurons typically receive multiple excitatory and inhibitory afferent and/or efferent inputs that integrate with each other, and the ultimate measured response properties of the neuron are driven by the neural integrations of these inputs. To study information processing in neural systems, it is necessary to understand the various inputs to a neuron or neural system, and the specific properties of these inputs. A powerful and technically relatively simple method to assess the functional role of certain inputs that a given neuron is receiving is to dynamically and reversibly suppress or eliminate these inputs, and measure the changes in the neuron's output caused by this manipulation. This can be accomplished by pharmacologically altering the neuron's immediate environment with piggy-back multibarrel electrodes. These electrodes consist of a single barrel recording electrode and a multibarrel drug electrode that can carry up to 4 different synaptic agonists or antagonists. The pharmacological agents can be applied iontophoretically at desired times during the experiment, allowing for time-controlled delivery and reversible reconfiguration of synaptic inputs. As such, pharmacological manipulation of the microenvironment represents a powerful and unparalleled method to test specific hypotheses about neural circuit function.Here we describe how piggy-back electrodes are manufactured, and how they are used during in vivo experiments. The piggy-back system allows an investigator to combine a single barrel recording electrode of any arbitrary property (resistance, tip size, shape etc) with a multibarrel drug electrode. This is a major advantage over standard multi-electrodes, where all barrels have more or less similar shapes and properties. Multibarrel electrodes were first introduced over 40 years ago 1-3, and have undergone a number of design improvements 2,3 until the piggy-back type was introduced in the 1980s 4,5. Here we present a set of important improvements in the laboratory production of piggy-back electrodes that allow for deep brain penetration in intact in vivo animal preparations due to a relatively thin electrode shaft that causes minimal damage. Furthermore these electrodes are characterized by low noise recordings, and have low resistance drug barrels for very effective iontophoresis of the desired pharmacological agents.

Characterizing the buckling behavior of cylindrical hollow and hybrid specimens by experimental upsetting tests

In the research of the compound forging of steel-aluminum parts mostly the upsetting test is used. In this paper the factors influencing the buckling behavior during the upsetting of mono hollow cylinders and hybrid steel-aluminum specimens are examined and characterized by two parameters. The buckle ratio is used as a measurement for the uniformity of the part geometry in radial direction and the buckle distance provides information about the part geometry in axial direction. The results gained by the upsetting of hollow cylinders show that the reproducibility depends on the wall thickness of the hollow steel cylinder. Above a forming temperature of T = 750 °C a transformation from mode II (double barrel profile) to mode I (single barrel profile) occurs. Furthermore, it could be shown, that the strain rate has no influence on the buckling behavior in both the upsetting of hollow cylinders as well as the upsetting of hybrid specimens. The results gained by the upsetting of hybrid steel aluminum specimens show that with increasing forming temperature the hybrid specimens with a wall thickness of the steel casing of s = 1 mm form more homogeneously in radial direction. In addition the scatter of the results decreases with increasing forming temperature.

“The Black and Cruel Demon” and Its Transformations of Space:

“The Black and Cruel Demon” and Its Transformations of Space:

Non Public Spaces

Non Public Spaces Imre Szeman (bio) Invisible Oil. Ernst Logar. Springer. http://www.springer.com. 94 pages; cloth, $39.95. How could oil ever be invisible? During the second half of 2011, oil was constantly in the news, mainly as a consequence of the protracted public and political debate over U.S. approval of TransCanada Corporation's Keystone XL pipeline. The new year promises to bring little relief from oil news, whether because of the role that the Keystone XL will undoubtedly play in the 2012 U.S. presidential election, or due to the start of hearings in Canada about the Northern Gateway pipeline, or because of the myriad other stories that will inevitably arise in relation to oil: rising prices at the pumps, sizable investments in new explorations, geopolitical wrangling to secure energy supply, reports of enormous corporate profits, and further news about the ecological devastation wrought by oil economies. Though we rarely set eyes on its physical substance despite the depths of our dependence on it, the ongoing drama of power, profit, and violence that surrounds oil is very much part of daily life. Yet despite the public prominence of this commodity, Austrian artist Ernst Logar is right to insist on oil's invisibility. Invisible Oil documents Logar's exhibit of the same name held at Peacock Visual Arts in 2008 in Aberdeen, Scotland. Consisting of large format photo and text pieces and a series of innovative installations, Invisible Oil continues Logar's ongoing artistic exploration of the social mechanisms and historical truisms (from money in 2009's Monetary Interventions in Public Space to the concept of sustainability in 2010's Sustainable Transformation) that animate and enable life in late capitalism. Logar's object here is oil, but oil as it is lived in Aberdeen, a community that has experienced the destabilizing effects of being near the epicenter of a major oil field. The city's economy was on the decline in the 1960s until the opening up of the North Sea oil fields in the 1970s in the wake of the OPEC crisis led to an economic revival. It has also brought with it inflation, crime (Aberdeen has the second highest crime rate in Scotland), problems with income distribution, and, now that the North Sea is a decade past peak production, a looming economic and social crisis. The book is interspersed with photos that Logar took of the city of Aberdeen while he was an artist in residence there in 2008 that provide some helpful visual context for the issues that he investigates. However, these photos are not included in the exhibit that this book documents, which is just as well: to my mind, the pieces included in the show engage in a more ambitious and critical interrogation of the consequences of life with oil than such city scenes could ever do. The primary exhibit space of Invisible Oil consists of images mounted on three sides of a rectangular room. At the center of the room sits a huge Lucite drum on a metal plinth. The drum contains a single barrel of oil: forty-two gallons sourced by Logar from a Scottish refinery, crude whose origins lie not in the North Sea, but in Venezuela—an immediate sign of the global networks along which this commodity circulates. Along one wall is a series of responses (either on letterhead or email printouts) from oil companies to the artist's requests for access to three sites: the well-head of an offshore rig, a lab where crude oil is analyzed, and a company's conference room. These letters reveal the original name of Logar's project to be "Non Public Spaces"; the photos that he had hoped to take were clearly intended to render visible sites deemed to be essential to the production of oil but which are hidden from view, despite their power in shaping publics in Aberdeen and elsewhere. With one exception (one company gave him access to their lab, photos of which are included in another section of Invisible Oil), none agreed to his request; it was only a single company that answered his request for a barrel of oil as well. Perversely, one might want...

Localization of single barrel column by means of a volumetric current source density analysis in the somatosensory cortex of rat

Localization of single barrel column by means of a volumetric current source density analysis in the somatosensory cortex of rat

Design and performance of a punch mechanism based pellet injector for alternative injection in the large helical device

A low speed single barrel pellet injector, using a mechanical punch device has been developed for alternative injection in the large helical device. A pellet is injected by the combined operation of a mechanical punch and a pneumatic propellant system. The pellet shape is cylindrical, 3 mm in diameter and 3 mm in length. Using this technique the speed of the pellet can be controlled flexibly in the range of 100-450 m/s, and a higher speed can be feasible for a higher gas pressure. The injector is equipped with a guide tube selector to direct the pellet to different injection locations. Pellets are exposed to several curved parts with the curvature radii R(c) = 0.8 and 0.3 m when they are transferred in guided tubes to the respective injection locations. Pellet speed variation with pressure at different pellet formation temperatures has been observed. Pellet intactness tests through these guide tubes show a variation in the intact speed limit over a range of pellet formation temperatures from 6.5 to 9.8 K. Pellet speed reduction of less than 6% has been observed after the pellet moves through the curved guide tubes.

Uncoupling Dendrite Growth and Patterning: Single-Cell Knockout Analysis of NMDA Receptor 2B

N-methyl-D-aspartate receptors (NMDARs) play important functions in neural development. NR2B is the predominant NR2 subunit of NMDAR in the developing brain. Here we use mosaic analysis with double markers (MADM) to knock out NR2B in isolated single cells and analyze its cell-autonomous function in dendrite development. NR2B mutant dentate gyrus granule cells (dGCs) and barrel cortex layer 4 spiny stellate cells (bSCs) have similar dendritic growth rates, total length, and branch number as control cells. However, mutant dGCs maintain supernumerary primary dendrites resulting from a pruning defect. Furthermore, while control bSCs restrict dendritic growth to a single barrel, mutant bSCs maintain dendritic growth in multiple barrels. Thus, NR2B functions cell autonomously to regulate dendrite patterning to ensure that sensory information is properly represented in the cortex. Our study also indicates that molecular mechanisms that regulate activity-dependent dendrite patterning can be separated from those that control general dendrite growth and branching.

The integration and engineering of the ATLAS SemiConductor Tracker Barrel

The ATLAS SemiConductor Tracker (SCT) was built in three sections: a barrel and two end-caps. This paper describes the design, construction and final integration of the barrel section. The barrel is constructed around four nested cylinders that provide a stable and accurate support structure for the 2112 silicon modules and their associated services. The emphasis of this paper is directed at the aspects of engineering design that turned a concept into a fully-functioning detector, as well as the integration and testing of large sub-sections of the final SCT barrel detector. The paper follows the chronology of the construction. The main steps of the assembly are described with the results of intermediate tests. The barrel service components were developed and fabricated in parallel so that a flow of detector modules, cooling loops, opto-harnesses and Frequency-Scanning-Interferometry (FSI) alignment structures could be assembled onto the four cylinders. Once finished, each cylinder was conveyed to the next site for the mounting of modules to form a complete single barrel. Extensive electrical and thermal function tests were carried out on the completed single barrels. In the next stage, the four single barrels and thermal enclosures were combined into the complete SCT barrel detector so that it could be integrated with the Transition Radiation Tracker (TRT) barrel to form the central part of the ATLAS inner detector. Finally, the completed SCT barrel was tested together with the TRT barrel in noise tests and using cosmic rays.

Thalamocortical transformations of periodic stimuli: the effect of stimulus velocity and synaptic short-term depression in the vibrissa–barrel system

Recent works on the response of barrel neurons to periodic deflections of the rat vibrissae have shown that the stimulus velocity is encoded in the corti cal spike rate (Pinto et al., Journal of Neurophysiology, 83(3), 1158-1166, 2000; Arabzadeh et al., Journal of Neuroscience, 23(27), 9146-9154, 2003). Other studies have reported that repetitive pulse stimulation produces band-pass filtering of the barrel response rate centered around 7-10 Hz (Garabedian et al., Journal of Neurophysiology, 90, 1379-1391, 2003) whereas sinusoidal stimulation gives an increasing rate up to 350 Hz (Arabzadeh et al., Journal of Neuroscience, 23(27), 9146-9154, 2003). To explore the mechanisms underlying these results we propose a simple computational model consisting in an ensemble of cells in the ventro-posterior medial thalamic nucleus (VPm) encoding the stimulus velocity in the temporal profile of their response, connected to a single barrel cell through synapses showing short-term depression. With sinusoidal stimulation, encoding the velocity in VPm facilitates the response as the stimulus frequency increases and it causes the velocity to be encoded in the cortical rate in the frequency range 20-100 Hz. Synaptic depression does not suppress the response with sinusoidal stimulation but it produces a band-pass behavior using repetitive pulses. We also found that the passive properties of the cell membrane eventually suppress the response to sinusoidal stimulation at high frequencies, something not observed experimentally. We argue that network effects not included here must be important in sustaining the response at those frequencies.