Sample records for structured bipolar plate

  1. Novel Structured Metal Bipolar Plates for Low Cost Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Conghua

    Bipolar plates are an important component in fuel cell stacks and accounts for more than 75% of stack weight and volume, and 20% of the stack cost. The technology development of metal bipolar plates can effectively reduce the fuel cells stack weight and volume over 50%. The challenge is to protect metal plate from corrosion at low cost for the broad commercial applications. While most of today’s PEM fuel cell metallic bipolar plate technologies use some precious metal, the focus of this SBIR project is to develop a low cost, novel nano-structured metal bipolar plate coating technology without using anymore » precious metal. The technology must meet the performance and cost requirements for automobile applications.« less

  2. Novel Structured Metal Bipolar Plates for Low Cost Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Conghua

    2013-08-15

    Bipolar plates are an important component in fuel cell stacks and accounts for more than 75% of stack weight and volume, and 20% of the stack cost. The technology development of metal bipolar plates can effectively reduce the fuel cells stack weight and volume over 50%. The challenge is to protect metal plate from corrosion at low cost for the broad commercial applications. While most of today’s PEM fuel cell metallic bipolar plate technologies use some precious metal, the focus of this SBIR project is to develop a low cost, novel nano-structured metal bipolar plate technology without using any preciousmore » metal. The technology will meet the performance and cost requirements for automobile applications. Through the Phase I project, TreadStone has identified the corrosion resistant and electrically conductive titanium oxide for the metal bipolar plate surface protection for automotive PEM fuel cell applications. TreadStone has overcome the manufacturing issues to apply the coating on metal substrate surface, and has demonstrated the feasibility of the coated stainless steel plates by ex-situ evaluation tests and the in-situ fuel cell long term durability test. The test results show the feasibility of the proposed nano-structured coating as the low cost metal bipolar plates of PEM fuel cells. The plan for further technology optimization is also outlined for the Phase II project.« less

  3. The Investigation and Development of Low Cost Hardware Components for Proton-Exchange Membrane Fuel Cells - Final Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    George A. Marchetti

    1999-12-15

    Proton exchange membrane (PEM) fuel cell components, which would have a low-cost structure in mass production, were fabricated and tested. A fuel cell electrode structure, comprising a thin layer of graphite (50 microns) and a front-loaded platinum catalyst layer (600 angstroms), was shown to produce significant power densities. In addition, a PEM bipolar plate, comprising flexible graphite, carbon cloth flow-fields and an integrated polymer gasket, was fabricated. Power densities of a two-cell unit using this inexpensive bipolar plate architecture were shown to be comparable to state-of-the-art bipolar plates.

  4. Lightweight Stacks of Direct Methanol Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram; Valdez, Thomas

    2004-01-01

    An improved design concept for direct methanol fuel cells makes it possible to construct fuel-cell stacks that can weigh as little as one-third as much as do conventional bipolar fuel-cell stacks of equal power. The structural-support components of the improved cells and stacks can be made of relatively inexpensive plastics. Moreover, in comparison with conventional bipolar fuel-cell stacks, the improved fuel-cell stacks can be assembled, disassembled, and diagnosed for malfunctions more easily. These improvements are expected to bring portable direct methanol fuel cells and stacks closer to commercialization. In a conventional bipolar fuel-cell stack, the cells are interspersed with bipolar plates (also called biplates), which are structural components that serve to interconnect the cells and distribute the reactants (methanol and air). The cells and biplates are sandwiched between metal end plates. Usually, the stack is held together under pressure by tie rods that clamp the end plates. The bipolar stack configuration offers the advantage of very low internal electrical resistance. However, when the power output of a stack is only a few watts, the very low internal resistance of a bipolar stack is not absolutely necessary for keeping the internal power loss acceptably low.

  5. Carbon composite bipolar plate for high-temperature proton exchange membrane fuel cells (HT-PEMFCs)

    NASA Astrophysics Data System (ADS)

    Lee, Dongyoung; Lee, Dai Gil

    2016-09-01

    A carbon/epoxy composite bipolar plate is an ideal substitute for the brittle graphite bipolar plate for lightweight proton exchange membrane fuel cells (PEMFCs) because of its high specific strength and stiffness. However, conventional carbon/epoxy composite bipolar plates are not applicable for high-temperature PEMFCs (HT-PEMFCs) because these systems are operated at higher temperatures than the glass transition temperatures of conventional epoxies. Therefore, in this study, a cyanate ester-modified epoxy is adopted for the development of a carbon composite bipolar plate for HT-PEMFCs. The composite bipolar plate with exposed surface carbon fibers is produced without any surface treatments or coatings to increase the productivity and is integrated with a silicone gasket to reduce the assembly cost. The developed carbon composite bipolar plate exhibits not only superior electrical properties but also high thermo-mechanical properties. In addition, a unit cell test is performed, and the results are compared with those of the conventional graphite bipolar plate.

  6. 2017 Bipolar Plate Workshop Summary Report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kopasz, John P.; Benjamin, Thomas G.; Schenck, Deanna

    The Bipolar Plate (BP) Workshop was held at USCAR1 in Southfield, Michigan on February 14, 2017 and included 63 participants from industry, government agencies, universities, and national laboratories with expertise in the relevant fields. The objective of the workshop was to identify research and development (R&D) needs, in particular early-stage R&D, for bipolar plates for polymer electrolyte membrane (PEM) fuel cells for transportation applications. The focus of the workshop was on materials, manufacturing, and design aspects of bipolar plates with the goal of meeting DOE’s 2020 bipolar plate targets. Of special interest was the cost target of ≤$3/kW for themore » bipolar plate.« less

  7. Bipolar plates for PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Middelman, E.; Kout, W.; Vogelaar, B.; Lenssen, J.; de Waal, E.

    The bipolar plates are in weight and volume the major part of the PEM fuel cell stack, and are also a significant contributor to the stack costs. The bipolar plate is therefore a key component if power density has to increase and costs must come down. Three cell plate technologies are expected to reach targeted cost price levels, all having specific advantages and drawbacks. NedStack has developed a conductive composite materials and a production process for fuel cell plates (bipolar and mono-polar). The material has a high electric and thermal conductivity, and can be processed into bipolar plates by a proprietary molding process. Process cycle time has been reduced to less than 10 s, making the material and process suitable for economical mass production. Other development work to increase material efficiency resulted in thin bipolar plates with integrated cooling channels, and integrated seals, and in two-component bipolar plates. Total thickness of the bipolar plates is now less than 3 mm, and will be reduced to 2 mm in the near future. With these thin integrated plates it is possible to increase power density up to 2 kW/l and 2 kW/kg, while at the same time reducing cost by integrating other functions and less material use.

  8. Catalytic bipolar interconnection plate for use in a fuel cell

    DOEpatents

    Lessing, Paul A.

    1996-01-01

    A bipolar interconnection plate for use between adjacent fuel cell units in a stacked fuel cell assembly. Each plate is manufactured from an intermetallic composition, examples of which include NiAl or Ni.sub.3 Al which can catalyze steam reforming of hydrocarbons. Distributed within the intermetallic structure of the plate is a ceramic filler composition. The plate includes a first side with gas flow channels therein and a second side with fuel flow channels therein. A protective coating is applied to the first side, with exemplary coatings including strontium-doped or calcium-doped lanthanum chromite. To produce the plate, Ni and Al powders are combined with the filler composition, compressed at a pressure of about 10,000-30,000 psi, and heated to about 600.degree.-1000.degree. C. The coating is then applied to the first side of the completed plate using liquid injection plasma deposition or other deposition techniques.

  9. Catalytic bipolar interconnection plate for use in a fuel cell

    DOEpatents

    Lessing, P.A.

    1996-03-05

    A bipolar interconnection plate is described for use between adjacent fuel cell units in a stacked fuel cell assembly. Each plate is manufactured from an intermetallic composition, examples of which include NiAl or Ni{sub 3}Al which can catalyze steam reforming of hydrocarbons. Distributed within the intermetallic structure of the plate is a ceramic filler composition. The plate includes a first side with gas flow channels therein and a second side with fuel flow channels therein. A protective coating is applied to the first side, with exemplary coatings including strontium-doped or calcium-doped lanthanum chromite. To produce the plate, Ni and Al powders are combined with the filler composition, compressed at a pressure of about 10,000--30,000 psi, and heated to about 600--1000 C. The coating is then applied to the first side of the completed plate using liquid injection plasma deposition or other deposition techniques. 6 figs.

  10. Highly conductive thermoplastic composites for rapid production of fuel cell bipolar plates

    DOEpatents

    Huang, Jianhua [Blacksburg, VA; Baird, Donald G [Blacksburg, VA; McGrath, James E [Blacksburg, VA

    2008-04-29

    A low cost method of fabricating bipolar plates for use in fuel cells utilizes a wet lay process for combining graphite particles, thermoplastic fibers, and reinforcing fibers to produce a plurality of formable sheets. The formable sheets are then molded into a bipolar plates with features impressed therein via the molding process. The bipolar plates formed by the process have conductivity in excess of 150 S/cm and have sufficient mechanical strength to be used in fuel cells. The bipolar plates can be formed as a skin/core laminate where a second polymer material is used on the skin surface which provides for enhanced conductivity, chemical resistance, and resistance to gas permeation.

  11. Lightweight bipolar storage battery

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1992-01-01

    An apparatus [10] is disclosed for a lightweight bipolar battery of the end-plate cell stack design. Current flow through a bipolar cell stack [12] is collected by a pair of copper end-plates [16a,16b] and transferred edgewise out of the battery by a pair of lightweight, low resistance copper terminals [28a,28b]. The copper terminals parallel the surface of a corresponding copper end-plate [16a,16b] to maximize battery throughput. The bipolar cell stack [12], copper end-plates [16a,16b] and copper terminals [28a,28b] are rigidly sandwiched between a pair of nonconductive rigid end-plates [20] having a lightweight fiber honeycomb core which eliminates distortion of individual plates within the bipolar cell stack due to internal pressures. Insulating foam [30] is injected into the fiber honeycomb core to reduce heat transfer into and out of the bipolar cell stack and to maintain uniform cell performance. A sealed battery enclosure [ 22] exposes a pair of terminal ends [26a,26b] for connection with an external circuit.

  12. Development of a brazing process for the production of water- cooled bipolar plates made of chromium-coated metal foils for PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Mueller, M.; Hoehlich, D.; Scharf, I.; Lampke, T.; Hollaender, U.; Maier, H. J.

    2016-03-01

    Beside lithium batteries, PEM fuel cells are the most promising strategy as a power source to achieve the targets for introducing and increasing the usage of electric vehicles. Due to limited space and weight problems, water cooled, metallic bipolar plates in a fuel cell metal stack are preferred in motor vehicles. These plates are stamped metal sheets with a complex structure, interconnected media-tight. To meet the multiple tasks and requirements in use, complex and expensive combinations of materials are currently in use (carbon fiber composites, graphite, gold-plated nickel, stainless and acid resistant steel). The production of such plates is expensive as it is connected with considerable effort or the usage of precious metals. As an alternative, metalloid nitrides (CrN, VN, W2N, etc.) show a high chemical resistance, hardness and a good conductivity. So this material category meets the basic requirements of a top layer. However, the standard methods for their production (PVD, CVD) are expensive and have a slow deposition rate and a lower layer thicknesses. Because of these limitations, a full functionality over the life cycle of a bipolar plate is not guaranteed. The contribution shows the development and quantification of an alternative production process for bipolar plates. The expectation is to get significant advantages from the combination of chromium electrodeposition and thermochemical treatment to form chromium nitrides. Both processes are well researched and suitable for series production. The thermochemical treatment of the chromium layer also enables a process-integrated brazing.

  13. Development of an Anti-Corrosion Conductive Nano Carbon Coating Layer on Metal Bipolar Plates.

    PubMed

    Yeo, Kiho; Kim, Juyong; Kim, Jongryoul

    2018-09-01

    For automotive applications of polymer electrolyte membrane fuel cells, the enhancement of the corrosion resistance of metal bipolar plates has been a critical issue with regard to the lifespan of fuel cell stacks. In this paper, we present a novel method for increasing the lifespan by means of a conductive carbon coating on bipolar plates. Conductive carbon films were plasma coated onto metal bipolar plates in a vacuum at various temperatures. As a result, 316L stainless plates with a 10-nm-thick carbon coating layer on a 20-nm-thick CrN undercoat layer showed-contact resistance of 10.71 mΩcm2@10 kgf/cm2 and a corrosion current of 0.5 μA/cm2@0.6 V. This thin coating layer with high conductivity and excellent corrosion resistance suggests a new, effective coating method for the mass production of metal bipolar plates.

  14. Effect of filler content on the properties of expanded- graphite-based composite bipolar plates for application in polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Masand, Aakash; Borah, Munu; Pathak, Abhishek K.; Dhakate, Sanjay R.

    2017-09-01

    Minimization of the weight and volume of a hydrogen-based PEM fuel cell stack is an essential area of research for the development and commercialization of PEMFCs for various applications. Graphite-based composite bipolar plates have significant advantages over conventional metallic bipolar plates due to their corrosion resistivity and low cost. On the other hand, expanded graphite is seen to be a potential candidate for facilitating the required electrical, thermal and mechanical properties of bipolar plates with a low density. Therefore, in the present study, the focus is on minimization of the high loading of graphite and optimizes its composition to meet the target properties of bipolar plates as per the USDOE target. Three types of expanded graphite (EG)-phenolic-resin-based composite bipolar plates were developed by partially replacing the expanded graphite content with natural graphite (NG) and carbon black as an additional filler. The three types of composite plate with the reinforcing constituent ratio EG:NG:R (25:25:50) give a bending strength of 49 MPa, a modulus of ~6 GPa, electrical conductivity  >100 S cm-1, a shore hardness of 55 and a bulk density of 1.55 g/cc. The 50 wt% loading of resin is sufficient to wet the 50 wt% filler content in the composite plate. This study gives an insight into using hybrid reinforcements in order to achieve the desired properties of bipolar plates.

  15. Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems

    NASA Technical Reports Server (NTRS)

    Mittelsteadt, Cortney K.; Braff, William

    2009-01-01

    In a substantial improvement over present alkaline systems, an advanced hybrid bipolar plate for a unitized fuel cell/electrolyzer has been developed. This design, which operates on pure feed streams (H2/O2 and water, respectively) consists of a porous metallic foil filled with a polymer that has very high water transport properties. Combined with a second metallic plate, the pore-filled metallic plates form a bipolar plate with an empty cavity in the center.

  16. Performance evaluation and characterization of metallic bipolar plates in a proton exchange membrane (PEM) fuel cell

    NASA Astrophysics Data System (ADS)

    Hung, Yue

    Bipolar plate and membrane electrode assembly (MEA) are the two most repeated components of a proton exchange membrane (PEM) fuel cell stack. Bipolar plates comprise more than 60% of the weight and account for 30% of the total cost of a fuel cell stack. The bipolar plates perform as current conductors between cells, provide conduits for reactant gases, facilitate water and thermal management through the cell, and constitute the backbone of a power stack. In addition, bipolar plates must have excellent corrosion resistance to withstand the highly corrosive environment inside the fuel cell, and they must maintain low interfacial contact resistance throughout the operation to achieve optimum power density output. Currently, commercial bipolar plates are made of graphite composites because of their relatively low interfacial contact resistance (ICR) and high corrosion resistance. However, graphite composite's manufacturability, permeability, and durability for shock and vibration are unfavorable in comparison to metals. Therefore, metals have been considered as a replacement material for graphite composite bipolar plates. Since bipolar plates must possess the combined advantages of both metals and graphite composites in the fuel cell technology, various methods and techniques are being developed to combat metallic corrosion and eliminate the passive layer formed on the metal surface that causes unacceptable power reduction and possible fouling of the catalyst and the electrolyte. The main objective of this study was to explore the possibility of producing efficient, cost-effective and durable metallic bipolar plates that were capable of functioning in the highly corrosive fuel cell environment. Bulk materials such as Poco graphite, graphite composite, SS310, SS316, incoloy 800, titanium carbide and zirconium carbide were investigated as potential bipolar plate materials. In this work, different alloys and compositions of chromium carbide coatings on aluminum and SS316 substrates were also tested for suitability in performing as PEM fuel cell bipolar plates. Interfacial contact resistance and accelerated corrosion resistance tests were carried out for various bulk materials and chromium carbide coatings. Results of the study showed that chromium carbide protective coatings had relatively low interfacial contact resistance and moderate corrosion resistance in comparison to other metals. Single fuel cells with 6.45cm2 and 50cm2 active areas were fabricated and tested for performance and lifetime durability using chromium carbide coated aluminum bipolar plates and graphite composite bipolar plates as a control reference. Polarization curves and power curves were recorded from these single cells under various load conditions. The results showed that coated aluminum bipolar plates had an advantage of anchoring the terminals directly into the plates resulting in higher power density of the fuel cell. This was due to the elimination of additional ICR to the power stack caused by the need for extra terminal plates. However, this study also revealed that direct terminal anchoring was efficient and useable only with metallic bipolar plates but was inapplicable to graphite composite plates due to the poor mechanical strength and brittleness of the graphite composite material. In addition, the 1000 hour lifetime testing of coated aluminum single cells conducted at 70°C cell temperature under cyclic loading condition showed minimal power degradation (<5%) due to metal corrosion. Surface characterization was also conducted on the bipolar plates and MEAs to identify possible chemical change to their surfaces during the fuel cell operation and the electrochemical reaction. The single cell performance evaluation was complemented by an extended study on the fuel cell stack level. For the latter, a ten-cell graphite composite stack with a 40 cm2 active area was fabricated and evaluated for the effect of humidity and operating temperature on the stack performance. Graphite plates were selected for this study to eliminate any possible metal corrosion. A finite element analysis (FEA) model of a bipolar plate was developed to evaluate the effect of air cooling system design parameters and different bipolar plate materials on maintaining the PEM power stack at a safe operating temperature of 80°C or less. In the final stage of this work, a three-cell metallic stack with a 50 cm2 active area and coated aluminum bipolar plates was fabricated based on the positive results that were obtained from earlier studies. The three-cell stack was successfully operated and tested for 750 hours at different temperatures and power densities. This laboratory testing coupled with characterization studies showed that small amounts of aluminum oxide were observed on the coating surface due to localized imperfections in the coating and a lack of protection in the uncoated areas, such as internal manifolds and mounting plates. However, the scanning electron microscopy (SEM) and the energy dispersive x-ray spectroscopy (EDX) showed that coating thickness, chemistry, and surface morphology remained consistent after 750 hours of operation.

  17. Scale-up of Carbon/Carbon Bipolar Plates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    David P. Haack

    2009-04-08

    This project was focused upon developing a unique material technology for use in PEM fuel cell bipolar plates. The carbon/carbon composite material developed in this program is uniquely suited for use in fuel cell systems, as it is lightweight, highly conductive and corrosion resistant. The project further focused upon developing the manufacturing methodology to cost-effectively produce this material for use in commercial fuel cell systems. United Technology Fuel Cells Corp., a leading fuel cell developer was a subcontractor to the project was interested in the performance and low-cost potential of the material. The accomplishments of the program included the developmentmore » and testing of a low-cost, fully molded, net-shape carbon-carbon bipolar plate. The process to cost-effectively manufacture these carbon-carbon bipolar plates was focused on extensively in this program. Key areas for cost-reduction that received attention in this program was net-shape molding of the detailed flow structures according to end-user design. Correlations between feature detail and process parameters were formed so that mold tooling could be accurately designed to meet a variety of flow field dimensions. A cost model was developed that predicted the cost of manufacture for the product in near-term volumes and long-term volumes (10+ million units per year). Because the roduct uses lowcost raw materials in quantities that are less than competitive tech, it was found that the cost of the product in high volume can be less than with other plate echnologies, and can meet the DOE goal of $4/kW for transportation applications. The excellent performance of the all-carbon plate in net shape was verified in fuel cell testing. Performance equivalent to much higher cost, fully machined graphite plates was found.« less

  18. Preparation of corrosion-resistant and conductive trivalent Cr-C coatings on 304 stainless steel for use as bipolar plates in proton exchange membrane fuel cells by electrodeposition

    NASA Astrophysics Data System (ADS)

    Wang, Hsiang-Cheng; Sheu, Hung-Hua; Lu, Chen-En; Hou, Kung-Hsu; Ger, Ming-Der

    2015-10-01

    In this study, Cr-C-coated bipolar plates are produced by electroplating on the SS304 plates with a machined flow channel. The resulting plates were tested using potentiodynamic and potentiostatic measurements in simulated PEMFC environments, which show that the bipolar plate coated with Cr-C exhibited good anticorrosion performance. The corrosive current density of the Cr-C coating formed for a plating time of 10 min for 10 h exhibits a low stable value of 1.51 × 10-10 A/cm2 during the potentiostatic test in a 0.5 M H2SO4 + 2 ppm HF solution at 70 °C with an air purge, indicating that the Cr-C coating plated for 10 min is stable in a cathode environment. The interfacial contact resistance (ICR) of the bipolar plate with the Cr-C coating clearly improved, presenting an ICR of 19.52 mΩ cm2 at a pressure of 138 N/cm2. The results from scanning electron microscopy (SEM) and ICR before and after the corrosion tests indicate that the bipolar plate with the Cr-C coating is electrochemically stable. In this study, the maximum power density (212.41 mW/cm2) is obtained at a cell temperature of 80 °C and a gas flow rate of 300 standard cubic centimeters per minute (sccm) when Cr-C coated SS304 bipolar plates were used.

  19. Highly conductive composites for fuel cell flow field plates and bipolar plates

    DOEpatents

    Jang, Bor Z; Zhamu, Aruna; Song, Lulu

    2014-10-21

    This invention provides a fuel cell flow field plate or bipolar plate having flow channels on faces of the plate, comprising an electrically conductive polymer composite. The composite is composed of (A) at least 50% by weight of a conductive filler, comprising at least 5% by weight reinforcement fibers, expanded graphite platelets, graphitic nano-fibers, and/or carbon nano-tubes; (B) polymer matrix material at 1 to 49.9% by weight; and (C) a polymer binder at 0.1 to 10% by weight; wherein the sum of the conductive filler weight %, polymer matrix weight % and polymer binder weight % equals 100% and the bulk electrical conductivity of the flow field or bipolar plate is at least 100 S/cm. The invention also provides a continuous process for cost-effective mass production of the conductive composite-based flow field or bipolar plate.

  20. Electrochemical Device Comprising Composite Bipolar Plate and Method of Using the Same

    NASA Technical Reports Server (NTRS)

    Mittelsteadt, Cortney K. (Inventor); Braff, William A. (Inventor)

    2013-01-01

    An electrochemical device and methods of using the same. In one embodiment, the electrochemical device may be used as a fuel cell and/or as an electrolyzer and includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, chemically-inert, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, as well as a fluid chamber and a non-porous an electrically-conductive plate.

  1. Electrochemical Device Comprising Composite Bipolar Plate and Method of Using the Same

    NASA Technical Reports Server (NTRS)

    Mittelsteadt, Cortney K. (Inventor); Braff, William A. (Inventor)

    2017-01-01

    An electrochemical device and methods of using the same. In one embodiment, the electrochemical device may be used as a fuel cell and/or as an electrolyzer and includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, chemically-inert, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, as well as a fluid chamber and a non-porous an electrically-conductive plate.

  2. Enhanced Corrosion Resistance and Interfacial Conductivity of TiC x/a-C Nanolayered Coatings via Synergy of Substrate Bias Voltage for Bipolar Plates Applications in PEMFCs.

    PubMed

    Yi, Peiyun; Zhang, Weixin; Bi, Feifei; Peng, Linfa; Lai, Xinmin

    2018-06-06

    Proton-exchange membrane fuel cells are one kind of renewable and clean energy conversion device, whose metallic bipolar plates are one of the key components. However, high interfacial contact resistance and poor corrosion resistance are still great challenges for the commercialization of metallic bipolar plates. In this study, we demonstrated a novel strategy for depositing TiC x /amorphous carbon (a-C) nanolayered coatings by synergy of 60 and 300 V bias voltage to enhance corrosion resistance and interfacial conductivity. The synergistic effects of bias voltage on the composition, microstructure, surface roughness, electrochemical corrosion behaviors, and interfacial conductivity of TiC x /a-C coatings were explored. The results revealed that the columnar structures in the inner layer were suppressed and the surface became rougher with the 300 V a-C layer outside. The composition analysis indicated that the sp 2 content increased with an increase of 300 V sputtering time. Due to the synergy strategy of bias voltage, lower corrosion current densities were achieved both in potentiostatic polarization (1.6 V vs standard hydrogen electrode) and potentiodynamic polarization. With the increase of 300 V sputtering time, the interfacial conductivity was improved. The enhanced corrosion resistance and interfacial conductivity of the TiC x /a-C coatings would provide new opportunities for commercial bipolar plates.

  3. Woven-grid sealed quasi-bipolar lead-acid battery construction and fabricating method

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E. (Inventor)

    1989-01-01

    A quasi-bipolar lead-acid battery construction includes a plurality of bipolar cells disposed in side-by-side relation to form a stack, and a pair of monoplanar plates at opposite ends of the stack, the cell stack and monopolar plates being contained within a housing of the battery. Each bipolar cell is loaded with an electrolyte and composed of a bipolar electrode plate and a pair of separator plates disposed on opposite sides of the electrode plate and peripherally sealed thereto. Each bipolar electrode plate is composed of a partition sheet and two bipolar electrode elements folded into a hairpin configuration and applied over opposite edges of the partition sheet so as to cover the opposite surfaces of the opposite halves thereof. Each bipolar electrode element is comprised of a woven grid with a hot-melt strip applied to a central longitudinal region of the grid along which the grid is folded into the hairpin configuration, and layers of negative and positive active material pastes applied to opposite halves of the grid on opposite sides of the central hot-melt strip. The grid is made up of strands of conductive and non-conductive yarns composing the respective transverse and longitudinal weaves of the grid. The conductive yarn has a multi-stranded glass core surrounded and covered by a lead sheath, whereas the non-conductive yarn has a multi-stranded glass core surrounded and covered by a thermally activated sizing.

  4. Bipolar battery construction

    NASA Technical Reports Server (NTRS)

    Edwards, Dean B. (Inventor); Rippel, Wally E. (Inventor)

    1981-01-01

    A lightweight, bipolar battery construction for lead acid batteries in which a plurality of thin, rigid, biplates each comprise a graphite fiber thermoplastic composition in conductive relation to lead stripes plated on opposite flat surfaces of the plates, and wherein a plurality of nonconductive thermoplastic separator plates support resilient yieldable porous glass mats in which active material is carried, the biplates and separator plates with active material being contained and maintained in stacked assembly by axial compression of the stacked assembly. A method of assembling such a bipolar battery construction.

  5. Development of fuel cell bipolar plates from graphite filled wet-lay thermoplastic composite materials

    NASA Astrophysics Data System (ADS)

    Huang, Jianhua; Baird, Donald G.; McGrath, James E.

    A method with the potential to produce economical bipolar plates with high electrical conductivity and mechanical properties is described. Thermoplastic composite materials consisting of graphite particles, thermoplastic fibers and glass or carbon fibers are generated by means of a wet-lay (paper-making) process to yield highly formable sheets. The sheets are then stacked and compression molded to form bipolar plates with gas flow channels. Poly(phenylene sulfide) (PPS) based wet-lay composite plates have in-plane conductivity of 200-300 S cm -1, tensile strength of 57 MPa, flexural strength of 96 MPa and impact strength (unnotched) of 81 J m -1 (1.5 ft-lb in. -1). These values well exceed industrial as well as Department of Energy requirements or targets and have never been reached before for composite bipolar plates. The use of wet-lay sheets also makes it possible to choose different components including polymer, graphite particle and reinforcement for the core and outer layers of the plate, respectively, to optimize the properties and/or reduce the cost of the plate. The through-plane conductivity (around 20 S cm -1) and half-cell resistance of the bipolar plate indicate that the through-plane conductivity of the material needs some improvement.

  6. Influence of Sintering Temperature on Mechanical and Physical properties of Mill Scale based Bipolar Plates for PEMFC

    NASA Astrophysics Data System (ADS)

    Khaerudini, Deni S.; Berliana, Rina; Prakoso, Gatra B.; Insiyanda, Dita R.; Alva, Sagir

    2018-03-01

    This work concerns the utilization of mill scale, a by-product of iron and steel formed during the hot rolling of steel, as a potential material for use as bipolar plates in proton exchange membrane fuel cells (PEMFCs). On the other hand, mill scale is considered a very rich in iron source having characteristic required such as for current collector in bipolar plate and would significantly contribute to lower the overall cost of PEMFC based fuel cell systems. In this study, the iron reach source of mill scale powder, after sieving of 150 mesh, was mechanically alloyed with the aluminium source containing 30 wt.% using a shaker mill for 3 h. The mixed powders were then pressed at 300 MPa and sintered at various temperatures of 400, 450 and 500 °C for 1 h under inert gas atmosphere. The structural changes of powder particles during mechanical alloying and after sintering were studied by x-ray diffractometry, scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), microhardness measurement, and density - porosity analysis. The details of the performance variation of three different sintering conditions can be preliminary explained by the metallographic and crystallographic structure and phase analysis as well as sufficient mechanical strength of the sintered materials was presented in this report.

  7. Pleated metal bipolar assembly

    DOEpatents

    Wilson, Mahlon S.; Zawodzinski, Christine

    2001-01-01

    A thin low-cost bipolar plate for an electrochemical cell is formed from a polymer support plate with first flow channels on a first side of the support plate and second flow channels on a second side of the support plate, where the first flow channels and second flow channels have intersecting locations and have a depth effective to form openings through the support plate at the intersecting locations. A first foil of electrically conductive material is pressed into the first flow channels. A second foil of electrically conductive material pressed into the second flow channels so that electrical contact is made between the first and second foils at the openings through the support plate. A particular application of the bipolar plate is in polymer electrolyte fuel cells.

  8. High surface area bio-waste based carbon as a superior electrode for vanadium redox flow battery

    NASA Astrophysics Data System (ADS)

    Maharjan, Makhan; Bhattarai, Arjun; Ulaganathan, Mani; Wai, Nyunt; Oo, Moe Ohnmar; Wang, Jing-Yuan; Lim, Tuti Mariana

    2017-09-01

    Activated carbon (AC) with high surface area (1901 m2 g-1) is synthesized from low cost bio-waste orange (Citrus sinensis) peel for vanadium redox flow battery (VRB). The composition, structure and electrochemical properties of orange peel derived AC (OP-AC) are characterized by elemental analyzer, field emission-scanning electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy. CV results show that OP-AC coated bipolar plate demonstrates improved electro-catalytic activity in both positive and negative side redox couples than the pristine bipolar plate electrode and this is ascribed to the high surface area of OP-AC which provides effective electrode area and better contact between the porous electrode and bipolar plate. Consequently, the performance of VRB in a static cell shows higher energy efficiency for OP-AC electrode than the pristine electrode at all current densities tested. The results suggest the OP-AC to be a promising electrode for VRB applications and can be incorporated into making conducting plastics electrode to lower the VRB cell stack weight and cost.

  9. Electrochemical Device Comprising an Electrically-Conductive, Selectively-Permeable Membrane

    NASA Technical Reports Server (NTRS)

    Laicer, Castro S. T. (Inventor); Mittelsteadt, Cortney K. (Inventor); Harrison, Katherine E. (Inventor); McPheeters, Bryn M. (Inventor)

    2017-01-01

    An electrochemical device, such as a fuel cell or an electrolyzer. In one embodiment, the electrochemical device includes a membrane electrode assembly (MEA), an anodic gas diffusion medium in contact with the anode of the MEA, a cathodic gas diffusion medium in contact with the cathode, a first bipolar plate in contact with the anodic gas diffusion medium, and a second bipolar plate in contact with the cathodic gas diffusion medium. Each of the bipolar plates includes an electrically-conductive, non-porous, liquid-permeable, substantially gas-impermeable membrane in contact with its respective gas diffusion medium, the membrane including a solid polymer electrolyte and a non-particulate, electrically-conductive material, such as carbon nanotubes, carbon nanofibers, and/or metal nanowires. In addition, each bipolar plate also includes an electrically-conductive fluid chamber in contact with the electrically-conductive, selectively-permeable membrane and further includes a non-porous and electrically-conductive plate in contact with the fluid chamber.

  10. Current density and catalyst-coated membrane resistance distribution of hydro-formed metallic bipolar plate fuel cell short stack with 250 cm2 active area

    NASA Astrophysics Data System (ADS)

    Haase, S.; Moser, M.; Hirschfeld, J. A.; Jozwiak, K.

    2016-01-01

    An automotive fuel cell with an active area of 250 cm2 is investigated in a 4-cell short stack with a current and temperature distribution device next to the bipolar plate with 560 current and 140 temperature segments. The electrical conductivities of the bipolar plate and gas diffusion layer assembly are determined ex-situ with this current scan shunt module. The applied fuel cell consists of bipolar plates constructed of 75-μm-thick, welded stainless-steel foils and a graphitic coating. The electrical conductivities of the bipolar plate and gas diffusion layer assembly are determined ex-situ with this module with a 6% deviation in in-plane conductivity. The current density distribution is evaluated up to 2.4 A cm-2. The entire cell's investigated volumetric power density is 4.7 kW l-1, and its gravimetric power density is 4.3 kW kg-1 at an average cell voltage of 0.5 V. The current density distribution is determined without influencing the operating cell. In addition, the current density distribution in the catalyst-coated membrane and its effective resistivity distribution with a finite volume discretisation of Ohm's law are evaluated. The deviation between the current density distributions in the catalyst-coated membrane and the bipolar plate is determined.

  11. Low hydrostatic head electrolyte addition to fuel cell stacks

    DOEpatents

    Kothmann, Richard E.

    1983-01-01

    A fuel cell and system for supply electrolyte, as well as fuel and an oxidant to a fuel cell stack having at least two fuel cells, each of the cells having a pair of spaced electrodes and a matrix sandwiched therebetween, fuel and oxidant paths associated with a bipolar plate separating each pair of adjacent fuel cells and an electrolyte fill path for adding electrolyte to the cells and wetting said matrices. Electrolyte is flowed through the fuel cell stack in a back and forth fashion in a path in each cell substantially parallel to one face of opposite faces of the bipolar plate exposed to one of the electrodes and the matrices to produce an overall head uniformly between cells due to frictional pressure drop in the path for each cell free of a large hydrostatic head to thereby avoid flooding of the electrodes. The bipolar plate is provided with channels forming paths for the flow of the fuel and oxidant on opposite faces thereof, and the fuel and the oxidant are flowed along a first side of the bipolar plate and a second side of the bipolar plate through channels formed into the opposite faces of the bipolar plate, the fuel flowing through channels formed into one of the opposite faces and the oxidant flowing through channels formed into the other of the opposite faces.

  12. Additive manufactured bipolar plate for high-efficiency hydrogen production in proton exchange membrane electrolyzer cells

    DOE PAGES

    Yang, Gaoqiang; Mo, Jingke; Kang, Zhenye; ...

    2017-05-06

    Additive manufacturing (AM) technology is capable of fast and low-cost prototyping from complex 3D digital models. To take advantage of this technology, a stainless steel (SS) plate with parallel flow field served as a combination of a cathode bipolar plate and a current distributor; it was fabricated using selective laser melting (SLM) techniques and investigated in a proton exchange membrane electrolyzer cell (PEMEC) in-situ for the first time. The experimental results show that the PEMEC with an AM SS cathode bipolar plate can achieve an excellent performance for hydrogen production for a voltage of 1.779 V and a current densitymore » of 2.0 A/cm 2. The AM SS cathode bipolar plate was also characterized by SEM and EDS, and the results show a uniform elemental distribution across the plate with very limited oxidization. As a result, this research demonstrates that AM method could be a route to aid cost-effective and rapid development of PEMECs.« less

  13. Additive manufactured bipolar plate for high-efficiency hydrogen production in proton exchange membrane electrolyzer cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Gaoqiang; Mo, Jingke; Kang, Zhenye

    Additive manufacturing (AM) technology is capable of fast and low-cost prototyping from complex 3D digital models. To take advantage of this technology, a stainless steel (SS) plate with parallel flow field served as a combination of a cathode bipolar plate and a current distributor; it was fabricated using selective laser melting (SLM) techniques and investigated in a proton exchange membrane electrolyzer cell (PEMEC) in-situ for the first time. The experimental results show that the PEMEC with an AM SS cathode bipolar plate can achieve an excellent performance for hydrogen production for a voltage of 1.779 V and a current densitymore » of 2.0 A/cm 2. The AM SS cathode bipolar plate was also characterized by SEM and EDS, and the results show a uniform elemental distribution across the plate with very limited oxidization. As a result, this research demonstrates that AM method could be a route to aid cost-effective and rapid development of PEMECs.« less

  14. PEM fuel cell bipolar plate material requirements for transportation applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Borup, R.L.; Stroh, K.R.; Vanderborgh, N.E.

    1996-04-01

    Cost effective bipolar plates are currently under development to help make proton exchange membrane (PEM) fuel cells commercially viable. Bipolar plates separate individual cells of the fuel cell stack, and thus must supply strength, be electrically conductive, provide for thermal control of the fuel stack, be a non-porous materials separating hydrogen and oxygen feed streams, be corrosion resistant, provide gas distribution for the feed streams and meet fuel stack cost targets. Candidate materials include conductive polymers and metal plates with corrosion resistant coatings. Possible metals include aluminium, titanium, iron/stainless steel and nickel.

  15. Corrosion test cell for bipolar plates

    DOEpatents

    Weisbrod, Kirk R.

    2002-01-01

    A corrosion test cell for evaluating corrosion resistance in fuel cell bipolar plates is described. The cell has a transparent or translucent cell body having a pair of identical cell body members that seal against opposite sides of a bipolar plate. The cell includes an anode chamber and an cathode chamber, each on opposite sides of the plate. Each chamber contains a pair of mesh platinum current collectors and a catalyst layer pressed between current collectors and the plate. Each chamber is filled with an electrolyte solution that is replenished with fluid from a much larger electrolyte reservoir. The cell includes gas inlets to each chamber for hydrogen gas and air. As the gases flow into a chamber, they pass along the platinum mesh, through the catalyst layer, and to the bipolar plate. The gas exits the chamber through passageways that provide fluid communication between the anode and cathode chambers and the reservoir, and exits the test cell through an exit port in the reservoir. The flow of gas into the cell produces a constant flow of fresh electrolyte into each chamber. Openings in each cell body is member allow electrodes to enter the cell body and contact the electrolyte in the reservoir therein. During operation, while hydrogen gas is passed into one chamber and air into the other chamber, the cell resistance is measured, which is used to evaluate the corrosion properties of the bipolar plate.

  16. Development of a Woven-Grid Quasi-Bipolar Battery

    NASA Technical Reports Server (NTRS)

    Tokumaru, P.; Rippel, W.; Zambrano, T.

    1998-01-01

    This report describes an analytical and experimental investigation of AeroVironment's Quasi-Bipolar battery concept. The modelling/battery design part of the study demonstrates that there is a trade-off between thermal and specified electrical performance. Even so, quasi-bipolar batteries can be designed, with ten times better thermal uniformity, that meet or exceed current state-of-the-art hybrid-electric vehicle battery pack performance, even using the same active materials. The thermal uniformity, power, and energy for these quasi-bipolar battery packs is projected to be very good. The experimental part of the investigation demonstrates the concept of the quasi-bipolar plate applied to a lead foil current collector wrapping around two sides of an inexpensive plastic film core. Approximately 50 quasi-biplate samples were fabricated using a hot laminating press. Hot lamination with "texture" between the plastic and lead shows some promise as a low cost method for fabricating the plates. Five of these plates were assembled into two cells plus one two-cell battery. Data from these test cells were compared with existing data for similar true bipolar batteries. The positive side of the plates exhibited corrosion where not protected by the active material.

  17. Highly conductive, multi-layer composite precursor composition to fuel cell flow field plate or bipolar plate

    DOEpatents

    Jang, Bor Z [Centerville, OH; Zhamu, Aruna [Centerville, OH; Guo, Jiusheng [Centerville, OH

    2011-02-15

    This invention provides a moldable, multiple-layer composite composition, which is a precursor to an electrically conductive composite flow field plate or bipolar plate. In one preferred embodiment, the composition comprises a plurality of conductive sheets and a plurality of mixture layers of a curable resin and conductive fillers, wherein (A) each conductive sheet is attached to at least one resin-filler mixture layer; (B) at least one of the conductive sheets comprises flexible graphite; and (C) at least one resin-filler mixture layer comprises a thermosetting resin and conductive fillers with the fillers being present in a sufficient quantity to render the resulting flow field plate or bipolar plate electrically conductive with a conductivity no less than 100 S/cm and thickness-direction areal conductivity no less than 200 S/cm.sup.2.

  18. Bipolar electrocautery: A rodent model of Sunderland third-degree nerve injury.

    PubMed

    Moradzadeh, Arash; Brenner, Michael J; Whitlock, Elizabeth L; Tong, Alice Y; Luciano, Janina P; Hunter, Daniel A; Myckatyn, Terence M; Mackinnon, Susan E

    2010-01-01

    To determine the Sunderland classification of a bipolar electrocautery injury. Twenty-two rats received crush (a reproducible Sunderland second-degree injury) or bipolar electrocautery injury and were evaluated for functional, histomorphometric, and immunohistochemical recovery at 21 or 42 days. Animal experiments were performed between July 3 and December 12, 2007. Axonal regeneration and end plate reinnervation were evaluated in double transgenic cyan fluorescent protein-conjugated Thy1 and green fluorescent protein-conjugated S100 mice. Compared with crush injury, bipolar electrocautery injury caused greater disruption of myelin and neurofilament architecture at the injury site and decreased nerve fiber counts and percentage of neural tissue distal to the injury (P =.007). Complete functional recovery was seen after crush but not bipolar electrocautery injury. Serial live imaging demonstrated axonal regeneration at week 1 after crush and at week 3 after bipolar electrocautery injury. Qualitative assessment of motor end plate reinnervation at 42 days demonstrated complete neuromuscular end plate reinnervation in the crush group and only limited reinnervation in the bipolar electrocautery group. Bipolar electrocautery injury in a rodent model resulted in a Sunderland third-degree injury, characterized by gradual, incomplete recovery without intervention.

  19. Fuel cell design and assembly

    DOEpatents

    Myerhoff, Alfred

    1984-01-01

    The present invention is directed to a novel bipolar cooling plate, fuel cell design and method of assembly of fuel cells. The bipolar cooling plate used in the fuel cell design and method of assembly has discrete opposite edge and means carried by the plate defining a plurality of channels extending along the surface of the plate toward the opposite edges. At least one edge of the channels terminates short of the edge of the plate defining a recess for receiving a fastener.

  20. Corrosion resistant metallic bipolar plate

    DOEpatents

    Brady, Michael P [Oak Ridge, TN; Schneibel, Joachim H [Knoxville, TN; Pint, Bruce A [Knoxville, TN; Maziasz, Philip J [Oak Ridge, TN

    2007-05-01

    A corrosion resistant, electrically conductive component such as a bipolar plate for a PEM fuel cell includes 20 55% Cr, balance base metal such as Ni, Fe, or Co, the component having thereon a substantially external, continuous layer of chromium nitride.

  1. Titanium Carbide Bipolar Plate for Electrochemical Devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaConti, Anthony B.; Griffith, Arthur E.; Cropley, Cecelia C.

    Titanium carbide comprises a corrosion resistant, electrically conductive, non-porous bipolar plate for use in an electrochemical device. The process involves blending titanium carbide powder with a suitable binder material, and molding the mixture, at an elevated temperature and pressure.

  2. Integral gas seal for fuel cell gas distribution assemblies and method of fabrication

    DOEpatents

    Dettling, Charles J.; Terry, Peter L.

    1985-03-19

    A porous gas distribution plate assembly for a fuel cell, such as a bipolar assembly, includes an inner impervious region wherein the bipolar assembly has good surface porosity but no through-plane porosity and wherein electrical conductivity through the impervious region is maintained. A hot-pressing process for forming the bipolar assembly includes placing a layer of thermoplastic sealant material between a pair of porous, electrically conductive plates, applying pressure to the assembly at elevated temperature, and allowing the assembly to cool before removing the pressure whereby the layer of sealant material is melted and diffused into the porous plates to form an impervious bond along a common interface between the plates holding the porous plates together. The distribution of sealant within the pores along the surface of the plates provides an effective barrier at their common interface against through-plane transmission of gas.

  3. Method of fabricating an integral gas seal for fuel cell gas distribution assemblies

    DOEpatents

    Dettling, Charles J.; Terry, Peter L.

    1988-03-22

    A porous gas distribution plate assembly for a fuel cell, such as a bipolar assembly, includes an inner impervious region wherein the bipolar assembly has good surface porosity but no through-plane porosity and wherein electrical conductivity through the impervious region is maintained. A hot-pressing process for forming the bipolar assembly includes placing a layer of thermoplastic sealant material between a pair of porous, electrically conductive plates, applying pressure to the assembly at elevated temperature, and allowing the assembly to cool before removing the pressure whereby the layer of sealant material is melted and diffused into the porous plates to form an impervious bond along a common interface between the plates holding the porous plates together. The distribution of sealant within the pores along the surface of the plates provides an effective barrier at their common interface against through-plane transmission of gas.

  4. Titanium carbide bipolar plate for electrochemical devices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    LaConti, Anthony B.; Griffith, Arthur E.; Cropley, Cecelia C.

    A corrosion resistant, electrically conductive, non-porous bipolar plate is made from titanium carbide for use in an eletrochemical device. The process involves blending titanium carbide powder with a suitable binder material, and molding the mixture, at an elevated temperature and pressure.

  5. Development of the anode bipolar plate/membrane assembly unit for air breathing PEMFC stack using silicone adhesive bonding

    NASA Astrophysics Data System (ADS)

    Kim, Minkook; Lee, Dai Gil

    2016-05-01

    Polymer electrolyte membrane fuel cells (PEMFC) exhibit a wide power range, low operating temperature, high energy density and long life time. These advantages favor PEMFC for applications such as vehicle power sources, portable power, and backup power applications. With the push towards the commercialization of PEMFC, especially for portable power applications, the overall balance of plants (BOPs) of the systems should be minimized. To reduce the mass and complexity of the systems, air-breathing PEMFC stack design with open cathode channel configuration is being developed. However, the open cathode channel configuration incurs hydrogen leakage problem. In this study, the bonding strength of a silicon adhesive between the Nafion membrane and the carbon fiber/epoxy composite bipolar plate was measured. Then, an anode bipolar plate/membrane assembly unit which was bonded with the silicone adhesive was developed to solve the hydrogen leakage problem. The reliability of the anode bipolar plate/membrane assembly unit was estimated under the internal pressure of hydrogen by the FE analysis. Additionally, the gas sealability of the developed air breathing PEMFC unit cell was experimentally measured. Finally, unit cell performance of the developed anode bipolar plate/membrane assembly unit was tested and verified under operating conditions without humidity and temperature control.

  6. Design of metallic bipolar plates for PEM fuel cells.

    DOT National Transportation Integrated Search

    2012-01-01

    This project focused on the design and production of metallic bipolar plates for use in PEM fuel cells. Different metals were explored : and stainless steel was found out to be best suited to our purpose. Following the selection of metal, it was calc...

  7. Brazed bipolar plates for PEM fuel cells

    DOEpatents

    Neutzler, Jay Kevin

    1998-01-01

    A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprising corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant.

  8. Requirements and testing methods for surfaces of metallic bipolar plates for low-temperature PEM fuel cells

    NASA Astrophysics Data System (ADS)

    Jendras, P.; Lötsch, K.; von Unwerth, T.

    2017-03-01

    To reduce emissions and to substitute combustion engines automotive manufacturers, legislature and first users aspire hydrogen fuel cell vehicles. Up to now the focus of research was set on ensuring functionality and increasing durability of fuel cell components. Therefore, expensive materials were used. Contemporary research and development try to substitute these substances by more cost-effective material combinations. The bipolar plate is a key component with the greatest influence on volume and mass of a fuel cell stack and they have to meet complex requirements. They support bending sensitive components of stack, spread reactants over active cell area and form the electrical contact to another cell. Furthermore, bipolar plates dissipate heat of reaction and separate one cell gastight from the other. Consequently, they need a low interfacial contact resistance (ICR) to the gas diffusion layer, high flexural strength, good thermal conductivity and a high durability. To reduce costs stainless steel is a favoured material for bipolar plates in automotive applications. Steel is characterized by good electrical and thermal conductivity but the acid environment requires a high chemical durability against corrosion as well. On the one hand formation of a passivating oxide layer increasing ICR should be inhibited. On the other hand pitting corrosion leading to increased permeation rate may not occur. Therefore, a suitable substrate lamination combination is wanted. In this study material testing methods for bipolar plates are considered.

  9. Fabrication process analysis and experimental verification for aluminum bipolar plates in fuel cells by vacuum die-casting

    NASA Astrophysics Data System (ADS)

    Jin, Chul Kyu; Kang, Chung Gil

    2011-10-01

    There are various methods for the fabrication of bipolar plates, but these are still limited to machining and stamping processes. High-pressure die casting (HPDC) is an ideal process for the manufacture of bipolar plates This study aims to investigate the formability of bipolar plates for polymer electrolyte membrane fuel cells (PEMFCs) fabricated by vacuum HPDC of an Al-Mg alloy (ALDC6). The cavity of the mold consisted of a thin-walled plate (200 mm × 200 mm × 0.8 mm) with a layer of serpentine channel (50 mm × 50 mm). The location and direction of the channel in the final mold design was determined by computational simulation (MAGMA soft). In addition, simulation results for different conditions of plunger stroke control were compared to those from actual die-casting experiments. Under a vacuum pressure of 35 kPa and for injection speeds of 0.3 and 2.5 m s-1 in the low and high speed regions, respectively, the samples had few casting defects. In addition, the hardness was higher and porosity in microstructure was less than those of the samples made under other injection speed conditions. In case of thin-walled plates, vacuum die casting is beneficial in terms of formability compared to conventional die casting.

  10. Manufacturing and Performance Assessment of Stamped, Laser Welded, and Nitrided FeCrV Stainless Steel Bipolar Plates for Proton Exchange Membrane Fuel Cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brady, Michael P; Abdelhamid, Mahmoud; Dadheech, G

    A manufacturing and single-cell fuel cell performance study of stamped, laser welded, and gas nitrided ferritic stainless steel foils in an advanced automotive bipolar plate assembly design was performed. Two developmental foil compositions were studied: Fee20Cre4V and Fee23Cre4V wt.%. Foils 0.1 mm thick were stamped and then laser welded together to create single bipolar plate assemblies with cooling channels. The plates were then surface treated by pre-oxidation and nitridation in N2e4H2 based gas mixtures using either a conventional furnace or a short-cycle quartz lamp infrared heating system. Single-cell fuel cell testing was performed at 80 C for 500 h atmore » 0.3 A/cm2 using 100% humidification and a 100%/40% humidification cycle that stresses the membrane and enhances release of the fluoride ion and promotes a more corrosive environment for the bipolar plates. Periodic high frequency resistance potential-current scans during the 500 h fuel cell test and posttest analysis of the membrane indicated no resistance increase of the plates and only trace levels of metal ion contamination.« less

  11. Brazed bipolar plates for PEM fuel cells

    DOEpatents

    Neutzler, J.K.

    1998-07-07

    A liquid-cooled, bipolar plate separating adjacent cells of a PEM fuel cell comprises corrosion-resistant metal sheets brazed together so as to provide a passage between the sheets through which a dielectric coolant flows. The brazement comprises a metal which is substantially insoluble in the coolant. 6 figs.

  12. Optimization Design of Bipolar Plate Flow Field in PEM Stack

    NASA Astrophysics Data System (ADS)

    Wen, Ming; He, Kanghao; Li, Peilong; Yang, Lei; Deng, Li; Jiang, Fei; Yao, Yong

    2017-12-01

    A new design of bipolar plate flow field in proton exchange membrane (PEM) stack was presented to develop a high-performance transfer efficiency of the two-phase flow. Two different flow fields were studied by using numerical simulations and the performance of the flow fields was presented. the hydrodynamic properties include pressure gap between inlet and outlet, the Reynold’s number of the two types were compared based on the Navier-Stokes equations. Computer aided optimization software was implemented in the design of experiments of the preferable flow field. The design of experiments (DOE) for the favorable concept was carried out to study the hydrodynamic properties when changing the design parameters of the bipolar plate.

  13. The bipolar plate of AISI 1045 steel with chromized coatings prepared by low-temperature pack cementation for proton exchange membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Bai, Ching-Yuan; Wen, Tse-Min; Hou, Kung-Hsu; Ger, Ming-Der

    The low-temperature pack chromization, a reforming pack cementation process, is employed to modify AISI 1045 steel for the application of bipolar plates in PEMFC. The process is conducted to yield a coating, containing major Cr-carbides and minor Cr-nitrides, on the substrate in view of enhancing the steel's corrosion resistance and lowering interfacial contact resistance between the bipolar plate and gas diffusion layer. Electrical discharge machining and rolling approach are used as the pretreatment to produce an activated surface on the steel before pack chromization process to reduce operating temperatures and increase deposition rates. The rolled-chromized steel shows the lowest corrosion current density, 3 × 10 -8 A cm -2, and the smallest interfacial contact resistance, 5.9 mΩ cm 2, at 140 N cm -2 among all tested steels. This study clearly states the performance of 1045 carbon steel modified by activated and low-temperature pack chromization processes, which possess the potential to be bipolar plates in the application of PEMFC.

  14. Bipolar resistive switching in metal-insulator-semiconductor nanostructures based on silicon nitride and silicon oxide

    NASA Astrophysics Data System (ADS)

    Koryazhkina, M. N.; Tikhov, S. V.; Mikhaylov, A. N.; Belov, A. I.; Korolev, D. S.; Antonov, I. N.; Karzanov, V. V.; Gorshkov, O. N.; Tetelbaum, D. I.; Karakolis, P.; Dimitrakis, P.

    2018-03-01

    Bipolar resistive switching in metal-insulator-semiconductor (MIS) capacitor-like structures with an inert Au top electrode and a Si3N4 insulator nanolayer (6 nm thick) has been observed. The effect of a highly doped n +-Si substrate and a SiO2 interlayer (2 nm) is revealed in the changes in the semiconductor space charge region and small-signal parameters of parallel and serial equivalent circuit models measured in the high- and low-resistive capacitor states, as well as under laser illumination. The increase in conductivity of the semiconductor capacitor plate significantly reduces the charging and discharging times of capacitor-like structures.

  15. Composite bipolar plate for electrochemical cells

    DOEpatents

    Wilson, Mahlon S.; Busick, Deanna N.

    2001-01-01

    A bipolar separator plate for fuel cells consists of a molded mixture of a vinyl ester resin and graphite powder. The plate serves as a current collector and may contain fluid flow fields for the distribution of reactant gases. The material is inexpensive, electrically conductive, lightweight, strong, corrosion resistant, easily mass produced, and relatively impermeable to hydrogen gas. The addition of certain fiber reinforcements and other additives can improve the properties of the composite material without significantly increasing its overall cost.

  16. Enhancing the corrosion resistance of the 2205 duplex stainless steel bipolar plates in PEMFCs environment by surface enriched molybdenum

    NASA Astrophysics Data System (ADS)

    Jinlong, Lv; Zhuqing, Wang; Tongxiang, Liang; Ken, Suzuki; Hideo, Miura

    Surface molybdenum enrichment on 2205 duplex stainless steel was obtained by the ball milling technique. The electrochemical results showed molybdenum enrichment on the surface of 2205 duplex stainless steel improved its corrosion resistance in a typical proton exchange membrane fuel cell environment. This was mainly attributed to higher molybdenum content in the passive film formed on 2205 duplex stainless steel after ball milling. The decreased donor and acceptor concentrations improved significantly the corrosion resistance of surface molybdenum-enriched 2205 duplex stainless steel bipolar plates in the simulated cathodic proton exchange membrane fuel cells environment. In addition, the interfacial contact resistance of the 2205 duplex stainless steel bipolar plates slightly decreased due to surface molybdenum enrichment.

  17. Nickel hydrogen bipolar battery electrode design

    NASA Technical Reports Server (NTRS)

    Puglisi, V. J.; Russell, P.; Verrier, D.; Hall, A.

    1985-01-01

    The preferred approach of the NASA development effort in nickel hydrogen battery design utilizes a bipolar plate stacking arrangement to obtain the required voltage-capacity configuration. In a bipolar stack, component designs must take into account not only the typical design considerations such as voltage, capacity and gas management, but also conductivity to the bipolar (i.e., intercell) plate. The nickel and hydrogen electrode development specifically relevant to bipolar cell operation is discussed. Nickel oxide electrodes, having variable type grids and in thicknesses up to .085 inch are being fabricated and characterized to provide a data base. A selection will be made based upon a system level tradeoff. Negative (hydrpogen) electrodes are being screened to select a high performance electrode which can function as a bipolar electrode. Present nickel hydrogen negative electrodes are not capable of conducting current through their cross-section. An electrode was tested which exhibits low charge and discharge polarization voltages and at the same time is conductive. Test data is presented.

  18. Surface modification by carbon ion implantation for the application of ni-based amorphous alloys as bipolar plate in proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Kim, Min-Uk; Kim, Do-Hyang; Han, Seung-hee; Fleury, Eric; Seok, Hyun-Kwang; Cha, Pil-Ryung; Kim, Yu-Chan

    2011-04-01

    Ni-based amorphous alloys with surface modification by carbon ion implantation are proposed as an alternative bipolar plate material for polymer electrolyte membrane fuel cells (PEMFCs). Both Ni60Nb20Ti10Zr10 alloys with and without carbon ion implantation have corrosion resistance as good as graphite as well as much lower contact resistance than 316L stainless steel in the PEMFC environment. The formation of conductive surface carbide due to carbon ion implantation results in a decrease in the contact resistance to a level comparable to that of graphite. This combination of excellent properties indicates that carbon ion implanted Ni-based amorphous alloys can be potential candidate materials for bipolar plates in PEMFCs.

  19. Bipolar batteries based on Ebonex ® technology

    NASA Astrophysics Data System (ADS)

    Loyns, A. C.; Hill, A.; Ellis, K. G.; Partington, T. J.; Hill, J. M.

    Continuing work by Atraverda on the production of a composite-laminate form of the Ebonex ® material, that can be cheaply formulated and manufactured to form substrate plates for bipolar lead-acid batteries, is described. Ebonex ® is the registered trade name of a range of titanium suboxide ceramic materials, typically Ti 4O 7 and Ti 5O 9, which combine electrical conductivity with high corrosion and oxidation resistance. Details of the structure of the composite, battery construction techniques and methods for filling and forming of batteries are discussed. In addition, lifetime and performance data obtained by Atraverda from laboratory bipolar lead-acid batteries and cells are presented. Battery production techniques for both conventional monopolar and bipolar batteries are reviewed. The findings indicate that substantial time and cost savings may be realised in the manufacture of bipolar batteries in comparison to conventional designs. This is due to the fewer processing steps required and more efficient formation. The results indicate that the use of Ebonex ® composite material as a bipolar substrate will provide lightweight and durable high-voltage lead-acid batteries suitable for a wide range of applications including advanced automotive, stationary power and portable equipment.

  20. Characterization of Thermal and Mechanical Properties of Polypropylene-Based Composites for Fuel Cell Bipolar Plates and Development of Educational Tools in Hydrogen and Fuel Cell Technologies

    ERIC Educational Resources Information Center

    Lopez Gaxiola, Daniel

    2011-01-01

    In this project we developed conductive thermoplastic resins by adding varying amounts of three different carbon fillers: carbon black (CB), synthetic graphite (SG) and multi-walled carbon nanotubes (CNT) to a polypropylene matrix for application as fuel cell bipolar plates. This component of fuel cells provides mechanical support to the stack,…

  1. Bipolar plate/diffuser for a proton exchange membrane fuel cell

    DOEpatents

    Besmann, Theodore M.; Burchell, Timothy D.

    2001-01-01

    A combination bipolar plate/diffuser fuel cell component includes an electrically conducting solid material having: a porous region having a porous surface; and a hermetic region, the hermetic region defining at least a portion of at least one coolant channel, the porous region defining at least a portion of at least one reactant channel, the porous region defining a flow field medium for diffusing the reactant to the porous surface.

  2. Bipolar plate/diffuser for a proton exchange membrane fuel cell

    DOEpatents

    Besmann, Theodore M.; Burchell, Timothy D.

    2000-01-01

    A combination bipolar plate/diffuser fuel cell component includes an electrically conducting solid material having: a porous region having a porous surface; and a hermetic region, the hermetic region defining at least a portion of at least one coolant channel, the porous region defining at least a portion of at least one reactant channel, the porous region defining a flow field medium for diffusing the reactant to the porous surface.

  3. Fabrication of gas impervious edge seal for a bipolar gas distribution assembly for use in a fuel cell

    DOEpatents

    Kaufman, Arthur; Werth, John

    1986-01-01

    A bipolar gas reactant distribution assembly for use in a fuel cell is disclosed, the assembly having a solid edge seal to prevent leakage of gaseous reactants wherein a pair of porous plates are provided with peripheral slits generally parallel to, and spaced apart from two edges of the plate, the slit being filled with a solid, fusible, gas impervious edge sealing compound. The plates are assembled with opposite faces adjacent one another with a layer of a fusible sealant material therebetween the slits in the individual plates being approximately perpendicular to one another. The plates are bonded to each other by the simultaneous application of heat and pressure to cause a redistribution of the sealant into the pores of the adjacent plate surfaces and to cause the edge sealing compound to flow and impregnate the region of the plates adjacent the slits and comingle with the sealant layer material to form a continuous layer of sealant along the edges of the assembled plates.

  4. Surface characteristic of chemically converted graphene coated low carbon steel by electro spray coating method for polymer electrolyte membrane fuel cell bipolar plate.

    PubMed

    Kim, Jungsoo; Kim, Yang Do; Nam, Dae Geun

    2013-05-01

    Graphene was coated on low carbon steel (SS400) by electro spray coating method to improve its properties of corrosion resistance and contact resistance. Exfoliated graphite was made of the graphite by chemical treatment (Chemically Converted Graphene, CCG). CCG is distributed using dispersing agent, and low carbon steel was coated with diffuse graphene solution by electro spray coating method. The structure of the CCG was analyzed using XRD and the coating layer of surface was analyzed using SEM. Analysis showed that multi-layered graphite structure was destroyed and it was transformed in to fine layers graphene structure. And the result of SEM analysis on the surface and the cross section, graphene layer was uniformly formed with 3-5 microm thickness on the surface of substrate. Corrosion resistance test was applied in the corrosive solution which is similar to the polymer electrolyte membrane fuel cell (PEMFC) stack inside. And interfacial contact resistance (ICR) test was measured to simulate the internal operating conditions of PEMFC stack. As a result of measuring corrosion resistance and contact resistance, it could be confirmed that low carbon steel coated with CCG was revealed to be more effective in terms of its applicability as PEMFC bipolar plate.

  5. Cost and performance prospects for composite bipolar plates in fuel cells and redox flow batteries

    NASA Astrophysics Data System (ADS)

    Minke, Christine; Hickmann, Thorsten; dos Santos, Antonio R.; Kunz, Ulrich; Turek, Thomas

    2016-02-01

    Carbon-polymer-composite bipolar plates (BPP) are suitable for fuel cell and flow battery applications. The advantages of both components are combined in a product with high electrical conductivity and good processability in convenient polymer forming processes. In a comprehensive techno-economic analysis of materials and production processes cost factors are quantified. For the first time a technical cost model for BPP is set up with tight integration of material characterization measurements.

  6. Bipolarly stacked electrolyser for energy and space efficient fabrication of supercapacitor electrodes

    NASA Astrophysics Data System (ADS)

    Liu, Xiaojuan; Wu, Tao; Dai, Zengxin; Tao, Keran; Shi, Yong; Peng, Chuang; Zhou, Xiaohang; Chen, George Z.

    2016-03-01

    Stacked electrolysers with titanium bipolar plates are constructed for electrodeposition of polypyrrole electrodes for supercapacitors. The cathode side of the bipolar Ti plates are pre-coated with activated carbon. In this new design, half electrolysis occurs which significantly lowers the deposition voltage. The deposited electrodes are tested in a symmetrical unit cell supercapacitor and an asymmetrical supercapacitor stack. Both devices show excellent energy storage performances and the capacitance values are very close to the design value, suggesting a very high current efficiency during the electrodeposition. The electrolyser stack offers multi-fold benefits for preparation of conducting polymer electrodes, i.e. low energy consumption, facile control of the electrode capacitance and simultaneous preparation of a number of identical electrodes. Therefore, the stacked bipolar electrolyser is a technology advance that offers an engineering solution for mass production of electrodeposited conducting polymer electrodes for supercapacitors.

  7. High rate lithium/thionyl chloride bipolar battery development

    NASA Technical Reports Server (NTRS)

    Russell, Philip G.; Goebel, F.

    1994-01-01

    Presented in viewgraph format are results and accomplishments on the development of lithium/thionyl chloride bipolar batteries. Results include the development of manufacturing capability for producing large quantities of uniform cathodes and bipolar plates; the development of assembly, sealing, and activation procedures for fabrication of battery modules containing up to 150 cells in bipolar configuration; and the successful demonstration of a 10.7 kW 150-cell module with constant power pulse discharge, 20 second pulse, and 10 percent duty cycle.

  8. Development of the Ni-based Metallic glassy bipolar plates for Proton Exchange Membrane Fuel Cell (PEMFC)

    NASA Astrophysics Data System (ADS)

    Yamaura, S.; Yokoyama, M.; Kimura, H. M.; Inoue, A.

    2009-01-01

    Alloy optimization in the Ni80-xCrxP16B4 (x = 9-30 at%) alloy system was conducted in order to achieve low Tg, Tx and a large ΔTx. From this study, the Ni65Cr15P16B4 glassy alloy was found to be the optimal alloy. The static and potentiodynamic corrosion behaviours of this alloy were measured. As a result of polarization measurements, it was found that the current density of the non-polished glassy alloy sample was smaller than that of a SUS316L sample. By contrast, the current density of the surface-polished glassy sample was slightly larger than that of the SUS316L sample in the voltage range of 0.3-0.8 V. A bipolar plate was successfully produced by hot-pressing the glassy alloy sheet in a supercooled liquid state. The I-V characteristics of a single cell with the glassy bipolar plates were measured.

  9. Thin graphite bipolar plate with associated gaskets and carbon cloth flow-field for use in an ionomer membrane fuel cell

    DOEpatents

    Marchetti, George A.

    2003-01-03

    The present invention comprises a thin graphite plate with associated gaskets and pieces of carbon cloth that comprise a flow-field. The plate, gaskets and flow-field comprise a "plate and gasket assembly" for use in an ionomer membrane fuel cell, fuel cell stack or battery.

  10. Design concepts of high power bipolar rechargeable lithium battery

    NASA Technical Reports Server (NTRS)

    Shen, David H.; Halpert, Gerald

    1993-01-01

    The present study shows that current bipolar Li/TiS2 batteries using a 0.38 mm thick TiS2 bipolar plate can yield moderate specific power and also high specific energy battery. The computer design studies project that a 100 V, 10 A h bipolar Li/TiS2 battery can achieve 150 W h/kg, 210 W h/l, and 150 W/kg. The unoptimized experimental bipolar Li/TiS2 batteries (3 cells, 90 mA h) exhibited 47 W h/kg, 90 W h/l, and 140 W/kg. Preliminary results on the cycleability of the bipolar batteries are demonstrated. The results also show that enhanced rate capability can be achieved by using pulse discharge and longer rest period between pulses.

  11. Degradation of graphene coated copper in simulated proton exchange membrane fuel cell environment: Electrochemical impedance spectroscopy study

    NASA Astrophysics Data System (ADS)

    Ren, Y. J.; Anisur, M. R.; Qiu, W.; He, J. J.; Al-Saadi, S.; Singh Raman, R. K.

    2017-09-01

    Metallic materials are most suitable for bipolar plates of proton exchange membrane fuel cell (PEMFC) because they possess the required mechanical strength, durability, gas impermeability, acceptable cost and are suitable for mass production. However, metallic bipolar plates are prone to corrosion or they can passivate under PEMFC environment and interrupt the fuel cell operation. Therefore, it is highly attractive to develop corrosion resistance coating that is also highly conductive. Graphene fits these criteria. Graphene coating is developed on copper by chemical vapor deposition (CVD) with an aim to improving corrosion resistance of copper under PEMFC condition. The Raman Spectroscopy shows the graphene coating to be multilayered. The electrochemical degradation of graphene coated copper is investigated by electrochemical impedance spectroscopy (EIS) in 0.5 M H2SO4 solution at room temperature. After exposure to the electrolyte for up to 720 h, the charge transfer resistance (Rt) of the graphene coated copper is ∼3 times greater than that of the bare copper, indicating graphene coatings could improve the corrosion resistance of copper bipolar plates.

  12. Test Results of a Ten Cell Bipolar Nickel-hydrogen Battery

    NASA Technical Reports Server (NTRS)

    Cataldo, R. L.

    1984-01-01

    A study was initiated to design and evaluate a new design concept for nickel-hydrogen cells. This concept involved constructing a battery in a bipolar stack with cells consisting of a one plate for each nickel and hydrogen electrode. Preliminary designs at the system level of this concept promised improvements in both volumetric and gravimetric energy densities, thermal management, life extension, costs, and peak power capability over more conventional designs. Test results were most encouraging. This preprototype battery, built with less than ideal components and hardware, exceeded expectations. A total of 2000 LEO cycles at 80 percent depth of discharge were accrued. A cycle life goal of 30,000 cycles appears achievable with minor design changes. These improvements include advanced technology nickel electrodes, insulated bipolar plates and specifically designed frames to minimize shunt currents. The discharge rate capability of this design exceeds 25C. At the 10C discharge rate, 80% of the battery capacity can be withdrawn in six minutes. This data shows that the bipolar design is well suited for those applications requiring high peak power pulses.

  13. Effect of formation temperature on properties of graphite/stannum composite for bipolar plate

    NASA Astrophysics Data System (ADS)

    Selamat, Mohd Zulkefli; Yusuf, Muhammad Yusri Md; Wer, Tio Kok; Sahadan, Siti Norbaya; Malingam, Sivakumar Dhar; Mohamad, Noraiham

    2016-03-01

    Bipolar plates are key components in Proton Exchange Membrane (PEM) fuel cells. They carry current away from the cell and withstand the clamping force of the stack assembly. Therefore, PEM fuel cell bipolar plates must have high electrical conductivity and adequate mechanical strength, in addition to being light weight and low cost in terms of both applicable materials and production methods. In this research, the raw materials used to fabricate the high performance bipolar plate are Graphite (Gr), Stannum (Sn) and Polypropylene (PP). All materials used was in powder form and Gr and Sn act as fillers and the PP acts as binder. The ratio of fillers (Gr/Sn) and binder (PP) was fixed at 80:20. For the multi-conductive filler, small amount of Sn, which is 10 up to 20wt% (from the total weight of fillers 80%) have been added into Gr/Sn/PP composite. The fillers were mixed by using the ball mill machine. The second stage of mixing process between the mixer of fillers and binder is also carried out by using ball mill machine before the compaction process by the hot press machine. The effect of formation temperatures (160°C-170°C) on the properties of Gr/Sn/PP composite had been studied in detail, especially the electrical conductivity, bulk density, hardness and microstructure analysis of Gr/Sn/PP composite. The result shows that there are significant improvement in the electrical conductivity and bulk density, which are exceeding the US-DoE target with the maximum value of 265.35 S/cm and 1.682g/cm3 respectively.

  14. Unsplit bipolar pulse forming line

    DOEpatents

    Rhodes, Mark A [Pleasanton, CA

    2011-05-24

    A bipolar pulse forming transmission line module and system for linear induction accelerators having first, second, third, and fourth planar conductors which form a sequentially arranged interleaved stack having opposing first and second ends, with dielectric layers between the conductors. The first and second planar conductors are connected to each other at the first end, and the first and fourth planar conductors are connected to each other at the second end via a shorting plate. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short at the first end a high voltage from the third planar conductor to the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  15. Measurement of effective bulk and contact resistance of gas diffusion layer under inhomogeneous compression - Part I: Electrical conductivity

    NASA Astrophysics Data System (ADS)

    Vikram, Ajit; Chowdhury, Prabudhya Roy; Phillips, Ryan K.; Hoorfar, Mina

    2016-07-01

    This paper describes a measurement technique developed for the determination of the effective electrical bulk resistance of the gas diffusion layer (GDL) and the contact resistance distribution at the interface of the GDL and the bipolar plate (BPP). The novelty of this study is the measurement and separation of the bulk and contact resistance under inhomogeneous compression, occurring in an actual fuel cell assembly due to the presence of the channels and ribs on the bipolar plates. The measurement of the electrical contact resistance, contributing to nearly two-third of the ohmic losses in the fuel cell assembly, shows a non-linear distribution along the GDL/BPP interface. The effective bulk resistance of the GDL under inhomogeneous compression showed a decrease of nearly 40% compared to that estimated for homogeneous compression at different compression pressures. Such a decrease in the effective bulk resistance under inhomogeneous compression could be due to the non-uniform distribution of pressure under the ribs and the channels. This measurement technique can be used to identify optimum GDL, BPP and channel-rib structures based on minimum bulk and contact resistances measured under inhomogeneous compression.

  16. Comparison of characteristics of fluorine doped zinc and gallium tin oxide composite thin films deposited on stainless steel 316 bipolar plate by electron cyclotron resonance-metal organic chemical vapor deposition for proton exchange membrane fuel cells.

    PubMed

    Park, Jihun; Hudaya, Chairul; Lee, Joong Kee

    2011-09-01

    In order to replace the brittle graphite bipolar plates currently used for the PEMFC stack, coated SUS 316 was employed. As a metallic bipolar plate, coated SUS 316 can provide higher mechanical strength, better durability to shocks and vibration, less permeability, improved thermal and bulk electrical conductivity, as well as being thinner and lighter. To enhance the interfacial contact resistance and corrosion resistance of SUS 316, the deposition of GTO:F and ZTO:F composite films was carried out by ECR-MOCVD. The surface morphology of the films consisted of tiny elliptically shaped grains with a thickness of 1 microm. The corrosion current for GTO:F was 0.13 Acm(-2) which was much lower than that of bare SUS 316 (50.16 Acm(-2)). The GTO:F coated film had the smallest corrosion current due to the formation of a tight surface morphology with very few pin-holes. The GTO:F coated film exhibited the highest cell voltage and power density due to its lower ICR values.

  17. Effect of manufacturing process sequence on the corrosion resistance characteristics of coated metallic bipolar plates

    NASA Astrophysics Data System (ADS)

    Dur, Ender; Cora, Ömer Necati; Koç, Muammer

    2014-01-01

    Metallic bipolar plate (BPP) with high corrosion and low contact resistance, durability, strength, low cost, volume, and weight requirements is one of the critical parts of the PEMFC. This study is dedicated to understand the effect of the process sequence (manufacturing then coating vs. coating then manufacturing) on the corrosion resistance of coated metallic bipolar plates. To this goal, three different PVD coatings (titanium nitride (TiN), chromium nitride (CrN), zirconium nitride (ZrN)), with three thicknesses, (0.1, 0.5, 1 μm) were applied on BPPs made of 316L stainless steel alloy before and after two types of manufacturing (i.e., stamping or hydroforming). Corrosion test results indicated that ZrN coating exhibited the best corrosion protection while the performance of TiN coating was the lowest among the tested coatings and thicknesses. For most of the cases tested, in which coating was applied before manufacturing, occurrence of corrosion was found to be more profound than the case where coating was applied after manufacturing. Increasing the coating thickness was found to improve the corrosion resistance. It was also revealed that hydroformed BPPs performed slightly better than stamped BPPs in terms of the corrosion behavior.

  18. Development of new sealed bipolar lead-acid battery

    NASA Technical Reports Server (NTRS)

    Attia, Alan I.; Rowlette, J. J.

    1987-01-01

    New light weight composite bipolar plates which can withstand the corrosive environment of the lead acid battery have made possible the construction of a sealed bipolar lead acid battery that promises to achieve very high specific power levels and substantially higher energy densities than conventional lead acid batteries. Performance projections based on preliminary experimental results show that the peak specific power of the battery can be as high as 90 kW/kg, and that a specific power of 5 kW/kg can be sustained over several thousand pulses.

  19. The development of a new sealed bipolar lead-acid battery

    NASA Technical Reports Server (NTRS)

    Attia, A. I.; Rowlette, J. J.

    1988-01-01

    New light weight composite bipolar plates which can withstand the corrosive environment of the lead acid battery have made possible the construction of a sealed bipolar lead acid battery that promises to achieve very high specific power levels and substantially higher energy densities than conventional lead acid batteries. Performance projections based on preliminary experimental results show that the peak specific power of the battery can be as high as 90 kW/kg, and that a specific power of 5 kW/kg can be sustained over several thousand pulses.

  20. Micro-Tubular Fuel Cells

    NASA Technical Reports Server (NTRS)

    Kimble, Michael C.; Anderson, Everett B.; Jayne, Karen D.; Woodman, Alan S.

    2004-01-01

    Micro-tubular fuel cells that would operate at power levels on the order of hundreds of watts or less are under development as alternatives to batteries in numerous products - portable power tools, cellular telephones, laptop computers, portable television receivers, and small robotic vehicles, to name a few examples. Micro-tubular fuel cells exploit advances in the art of proton-exchange-membrane fuel cells. The main advantage of the micro-tubular fuel cells over the plate-and-frame fuel cells would be higher power densities: Whereas the mass and volume power densities of low-pressure hydrogen-and-oxygen-fuel plate-and-frame fuel cells designed to operate in the targeted power range are typically less than 0.1 W/g and 0.1 kW/L, micro-tubular fuel cells are expected to reach power densities much greater than 1 W/g and 1 kW/L. Because of their higher power densities, micro-tubular fuel cells would be better for powering portable equipment, and would be better suited to applications in which there are requirements for modularity to simplify maintenance or to facilitate scaling to higher power levels. The development of PEMFCs has conventionally focused on producing large stacks of cells that operate at typical power levels >5 kW. The usual approach taken to developing lower-power PEMFCs for applications like those listed above has been to simply shrink the basic plate-and-frame configuration to smaller dimensions. A conventional plate-and-frame fuel cell contains a membrane/electrode assembly in the form of a flat membrane with electrodes of the same active area bonded to both faces. In order to provide reactants to both electrodes, bipolar plates that contain flow passages are placed on both electrodes. The mass and volume overhead of the bipolar plates amounts to about 75 percent of the total mass and volume of a fuel-cell stack. Removing these bipolar plates in the micro-tubular fuel cell significantly increases the power density.

  1. Simulation and Experimental Study of Bipolar Plate on the Performance PEM Fuel cell

    NASA Astrophysics Data System (ADS)

    Chinnasa, Pornchai; Khamsuk, Pattama; Seechalee, Sarunya; Swatsitang, Ekaphan

    2017-09-01

    This research is a simulated and experimental study on effects of bipolar electrodes of a PEM fuel cell on its power conversion efficiency. The PEM fuel cell structure consists of bipolar electrodes, proton exchange membrane with catalysts, flow channels of gases. This research used fuel cell of 49 cm2 in active area as a research sample and the Comsol 4.4 was employed to simulate flow channels which are serpentine pattern for anode and parallel pattern for cathode. The parameters used were calculated effects of such parameters using Comsol 4.4. After the calculation has been completed, the prototype of the PEM fuel cell were fabricated using graphite plate as electrodes which had the channel height of 0.20 cm, proton exchange membrane using carbon-platinum catalyst. Finally, further it was found that the effect of temperature on the power conversion efficiency is not severely. And for anode, the concentration of hydrogen gas was reduced 64 wt% due to the reaction whereas in parallel channel of cathode the oxygen concentration was reduced by only 6 wt% from 23 wt% at the entrance to 17 wt% at the end. The maximum power output of the prototype operated under such condition was 0.28 W/cm2 calculated from maximum power output voltage (Vmp) of 0.70 V and maximum power output current density of 0.42 A/cm2 which was in good agreement with that simulated using Comsol 4.4 which revealed the power output of 0.29 W/cm2.

  2. Fully printed and integrated electrolyzer cells with additive manufacturing for high-efficiency water splitting

    DOE PAGES

    Yang, Gaoqiang; Mo, Jingke; Kang, Zhenye; ...

    2018-02-20

    Using additive manufacturing (AM) technology, a fundamental material and structure innovation was proposed to significantly increase the energy efficiency, and to reduce the weight, volume and component quantity of proton exchange membrane electrolyzer cells (PEMECs). Four conventional parts (liquid/gas diffusion layer, bipolar plate, gasket, and current distributor) in a PEMEC were integrated into one multifunctional AM plate without committing to tools or molds for the first time. In addition, since the interfacial contact resistances between those parts were eliminated, the comprehensive in-situ characterizations of AM cells showed that an excellent energy efficiency of up to 86.48% was achieved at 2more » A/cm2 and 80 degrees C, and the hydrogen generation rate was increased by 61.81% compared to the conventional cell. More importantly, the highly complex inner structures of the AM integrated multifunctional plates also exhibit the potential to break limitations of conventional manufacture methods for hydrogen generation and to open a door for the development of other energy conversion devices, including fuel cells, solar cells and batteries.« less

  3. Fully printed and integrated electrolyzer cells with additive manufacturing for high-efficiency water splitting

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Gaoqiang; Mo, Jingke; Kang, Zhenye

    Using additive manufacturing (AM) technology, a fundamental material and structure innovation was proposed to significantly increase the energy efficiency, and to reduce the weight, volume and component quantity of proton exchange membrane electrolyzer cells (PEMECs). Four conventional parts (liquid/gas diffusion layer, bipolar plate, gasket, and current distributor) in a PEMEC were integrated into one multifunctional AM plate without committing to tools or molds for the first time. In addition, since the interfacial contact resistances between those parts were eliminated, the comprehensive in-situ characterizations of AM cells showed that an excellent energy efficiency of up to 86.48% was achieved at 2more » A/cm2 and 80 degrees C, and the hydrogen generation rate was increased by 61.81% compared to the conventional cell. More importantly, the highly complex inner structures of the AM integrated multifunctional plates also exhibit the potential to break limitations of conventional manufacture methods for hydrogen generation and to open a door for the development of other energy conversion devices, including fuel cells, solar cells and batteries.« less

  4. Low-Cost and Durable Bipolar Plates for Proton Exchange Membrane Electrolyzers

    NASA Astrophysics Data System (ADS)

    Lettenmeier, P.; Wang, R.; Abouatallah, R.; Saruhan, B.; Freitag, O.; Gazdzicki, P.; Morawietz, T.; Hiesgen, R.; Gago, A. S.; Friedrich, K. A.

    2017-03-01

    Cost reduction and high efficiency are the mayor challenges for sustainable H2 production via proton exchange membrane (PEM) electrolysis. Titanium-based components such as bipolar plates (BPP) have the largest contribution to the capital cost. This work proposes the use of stainless steel BPPs coated with Nb and Ti by magnetron sputtering physical vapor deposition (PVD) and vacuum plasma spraying (VPS), respectively. The physical properties of the coatings are thoroughly characterized by scanning electron, atomic force microscopies (SEM, AFM); and X-ray diffraction, photoelectron spectroscopies (XRD, XPS). The Ti coating (50 μm) protects the stainless steel substrate against corrosion, while a 50-fold thinner layer of Nb decreases the contact resistance by almost one order of magnitude. The Nb/Ti-coated stainless steel bipolar BPPs endure the harsh environment of the anode for more than 1000 h of operation under nominal conditions, showing a potential use in PEM electrolyzers for large-scale H2 production from renewables.

  5. Low-Cost and Durable Bipolar Plates for Proton Exchange Membrane Electrolyzers

    PubMed Central

    Lettenmeier, P.; Wang, R.; Abouatallah, R.; Saruhan, B.; Freitag, O.; Gazdzicki, P.; Morawietz, T.; Hiesgen, R.; Gago, A. S.; Friedrich, K. A.

    2017-01-01

    Cost reduction and high efficiency are the mayor challenges for sustainable H2 production via proton exchange membrane (PEM) electrolysis. Titanium-based components such as bipolar plates (BPP) have the largest contribution to the capital cost. This work proposes the use of stainless steel BPPs coated with Nb and Ti by magnetron sputtering physical vapor deposition (PVD) and vacuum plasma spraying (VPS), respectively. The physical properties of the coatings are thoroughly characterized by scanning electron, atomic force microscopies (SEM, AFM); and X-ray diffraction, photoelectron spectroscopies (XRD, XPS). The Ti coating (50 μm) protects the stainless steel substrate against corrosion, while a 50-fold thinner layer of Nb decreases the contact resistance by almost one order of magnitude. The Nb/Ti-coated stainless steel bipolar BPPs endure the harsh environment of the anode for more than 1000 h of operation under nominal conditions, showing a potential use in PEM electrolyzers for large-scale H2 production from renewables. PMID:28294119

  6. Bipolar pulse forming line

    DOEpatents

    Rhodes, Mark A.

    2008-10-21

    A bipolar pulse forming transmission line module for linear induction accelerators having first, second, third, fourth, and fifth planar conductors which form an interleaved stack with dielectric layers between the conductors. Each conductor has a first end, and a second end adjacent an acceleration axis. The first and second planar conductors are connected to each other at the second ends, the fourth and fifth planar conductors are connected to each other at the second ends, and the first and fifth planar conductors are connected to each other at the first ends via a shorting plate adjacent the first ends. The third planar conductor is electrically connectable to a high voltage source, and an internal switch functions to short a high voltage from the first end of the third planar conductor to the first end of the fourth planar conductor to produce a bipolar pulse at the acceleration axis with a zero net time integral. Improved access to the switch is enabled by an aperture through the shorting plate and the proximity of the aperture to the switch.

  7. Corrosion-resistant, electrically-conductive plate for use in a fuel cell stack

    DOEpatents

    Carter, J David [Bolingbrook, IL; Mawdsley, Jennifer R [Woodridge, IL; Niyogi, Suhas [Woodridge, IL; Wang, Xiaoping [Naperville, IL; Cruse, Terry [Lisle, IL; Santos, Lilia [Lombard, IL

    2010-04-20

    A corrosion resistant, electrically-conductive, durable plate at least partially coated with an anchor coating and a corrosion resistant coating. The corrosion resistant coating made of at least a polymer and a plurality of corrosion resistant particles each having a surface area between about 1-20 m.sup.2/g and a diameter less than about 10 microns. Preferably, the plate is used as a bipolar plate in a proton exchange membrane (PEMFC) fuel cell stack.

  8. Evaluation of coated metallic bipolar plates for polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Yoon, Wonseok; Huang, Xinyu; Fazzino, Paul; Reifsnider, Kenneth L.; Akkaoui, Michael A.

    Metallic bipolar plates for polymer electrolyte membrane (PEM) fuel cells typically require coatings for corrosion protection. Other requirements for the corrosion protective coatings include low electrical contact resistance, good mechanical robustness, low material and fabrication cost. The authors have evaluated a number of protective coatings deposited on stainless steel substrates by electroplating and physical vapor deposition (PVD) methods. The coatings are screened with an electrochemical polarization test for corrosion resistance; then the contact resistance test was performed on selected coatings. The coating investigated include Gold with various thicknesses (2 nm, 10 nm, and 1 μm), Titanium, Zirconium, Zirconium Nitride (ZrN), Zirconium Niobium (ZrNb), and Zirconium Nitride with a Gold top layer (ZrNAu). The substrates include three types of stainless steel: 304, 310, and 316. The results show that Zr-coated samples satisfy the DOE target for corrosion resistance at both anode and cathode sides in typical PEM fuel cell environments in the short-term, but they do not meet the DOE contact resistance goal. Very thin gold coating (2 nm) can significantly decrease the electrical contact resistance, however a relatively thick gold coating (>10 nm) with our deposition method is necessary for adequate corrosion resistance, particularly for the cathode side of the bipolar plate.

  9. The effect of surface charge, negative and bipolar ionization on the deposition of airborne bacteria.

    PubMed

    Meschke, S; Smith, B D; Yost, M; Miksch, R R; Gefter, P; Gehlke, S; Halpin, H A

    2009-04-01

    A series of experiments were conducted to evaluate the effect of surface charge and air ionization on the deposition of airborne bacteria. The interaction between surface electrostatic potential and the deposition of airborne bacteria in an indoor environment was investigated using settle plates charged with electric potentials of 0, +/-2.5kV and +/-5kV. Results showed that bacterial deposition on the plates increased proportionally with increased potential to over twice the gravitational sedimentation rate at +5kV. Experiments were repeated under similar conditions in the presence of either negative or bipolar air ionization. Bipolar air ionization resulted in reduction of bacterial deposition onto the charged surfaces to levels nearly equal to gravitational sedimentation. In contrast, diffusion charging appears to have occurred during negative air ionization, resulting in an even greater deposition onto the oppositely charged surface than observed without ionization. Static charges on fomitic surfaces may attract bacteria resulting in deposition in excess of that expected by gravitational sedimentation or simple diffusion. Implementation of bipolar ionization may result in reduction of bacterial deposition. Fomitic surfaces are important vehicles for the transmission of infectious organisms. This study has demonstrated a simple strategy for minimizing charge related deposition of bacteria on surfaces.

  10. Sobol's sensitivity analysis for a fuel cell stack assembly model with the aid of structure-selection techniques

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Cho, Chongdu; Piao, Changhao; Choi, Hojoon

    2016-01-01

    This paper presents a novel method for identifying the main parameters affecting the stress distribution of the components used in assembly modeling of proton exchange membrane fuel cell (PEMFC) stack. This method is a combination of an approximation model and Sobol's method, which allows a fast global sensitivity analysis for a set of uncertain parameters using only a limited number of calculations. Seven major parameters, i.e., Young's modulus of the end plate and the membrane electrode assembly (MEA), the contact stiffness between the MEA and bipolar plate (BPP), the X and Y positions of the bolts, the pressure of each bolt, and the thickness of the end plate, are investigated regarding their effect on four metrics, i.e., the maximum stresses of the MEA, BPP, and end plate, and the stress distribution percentage of the MEA. The analysis reveals the individual effects of each parameter and its interactions with the other parameters. The results show that the X position of a bolt has a major influence on the maximum stresses of the BPP and end plate, whereas the thickness of the end plate has the strongest effect on both the maximum stress and the stress distribution percentage of the MEA.

  11. Thermal Simulation of Switching Pulses in an Insulated Gate Bipolar Transistor (IGBT) Power Module

    DTIC Science & Technology

    2015-02-01

    executed with SolidWorks Flow Simulation , a computational fluid-dynamics code. The graph in Fig. 2 shows the timing and amplitudes of power pulses...defined a convective flow of air perpendicular to the bottom surface of the mounting plate, with a velocity of 10 ft/s. The thermal simulations were...Thermal Simulation of Switching Pulses in an Insulated Gate Bipolar Transistor (IGBT) Power Module by Gregory K Ovrebo ARL-TR-7210

  12. Effect of graphite addition into mill scale waste as a potential bipolar plates material of proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Khaerudini, D. S.; Prakoso, G. B.; Insiyanda, D. R.; Widodo, H.; Destyorini, F.; Indayaningsih, N.

    2018-03-01

    Bipolar plates (BPP) is a vital component of proton exchange membrane fuel cells (PEMFC), which supplies fuel and oxidant to reactive sites, remove reaction products, collects produced current and provide mechanical support for the cells in the stack. This work concerns the utilization of mill scale, a by-product of iron and steel formed during the hot rolling of steel, as a potential material for use as BPP in PEMFC. On the other hand, mill scale is considered a very rich in iron source having characteristic required such as for current collector in BPP and would significantly contribute to lower the overall cost of PEMFC based fuel cell systems. In this study, the iron reach source of mill scale powder, after sieving of 150 mesh, was mechanically alloyed with the carbon source containing 5, 10, and 15 wt.% graphite using a shaker mill for 3 h. The mixed powders were then pressed at 300 MPa and sintered at 900 °C for 1 h under inert gas atmosphere. The structural changes of powder particles during mechanical alloying and after sintering were studied by X-ray diffractometry, optical microscopy, scanning electron microscopy, and microhardness measurement. The details of the presence of iron, carbon, and iron carbide (Fe-C) as the products of reactions as well as sufficient mechanical strength of the sintered materials were presented in this report.

  13. Bipolar Ag-Zn battery

    NASA Astrophysics Data System (ADS)

    Giltner, L. John

    1994-02-01

    The silver-zinc (AgZn) battery system has been unique in its ability to safely satisfy high power demand applications with low mass and volume. However, a new generation of defense, aerospace, and commercial applications will impose even higher power demands. These new power demands can be satisfied by the development of a bipolar battery design. In this configuration the power consuming, interelectrode current conductors are eliminated while the current is then conducted via the large cross-section electrode substrate. Negative and positive active materials are applied to opposite sides of a solid silver foil substrate. In addition to reducing the weight and volume required for a specified power level, the output voltage performance is also improved as follows. Reduced weight through: elimination of the plastic cell container; elimination of plate leads and intercell connector; and elimination of internal plate current collector. Increased voltage through: elimination of resistance of current collector; elimination of resistance of plate lead; and elimination of resistance of intercell connector. EPI worked previously on development of a secondary bipolar silver zinc battery. This development demonstrated the electrical capability of the system and manufacturing techniques. One difficulty with this development was mechanical problems with the seals. However, recent improvements in plastics and adhesives should eliminate the major problem of maintaining a seal around the periphery of the bipolar module. The seal problem is not as significant for a primary battery application or for a requirement for only a few discharge cycles. A second difficulty encountered was with activation (introducing electrolyte into the cell) and with venting gas from the cell without loss of electrolyte. During previous work, the following projections for energy density were made from test data for a high power system which demonstrated in excess of 50 discharge/charge cycles. Projected system power = 100 kilowatts; discharge time = 30 seconds; discharge current density = 1.75 amps/sq in.; system weight = 86 lbs (9.7 WH/lb); and system volume = 1071 cu. in. (.78 WH/cu. in.). EPI is currently working on a development program to produce a bipolar silver-zinc battery design for NASA. The potential application would be to power electromechanical actuators for space launch vehicles.

  14. Bipolar Ag-Zn battery

    NASA Technical Reports Server (NTRS)

    Giltner, L. John

    1994-01-01

    The silver-zinc (AgZn) battery system has been unique in its ability to safely satisfy high power demand applications with low mass and volume. However, a new generation of defense, aerospace, and commercial applications will impose even higher power demands. These new power demands can be satisfied by the development of a bipolar battery design. In this configuration the power consuming, interelectrode current conductors are eliminated while the current is then conducted via the large cross-section electrode substrate. Negative and positive active materials are applied to opposite sides of a solid silver foil substrate. In addition to reducing the weight and volume required for a specified power level, the output voltage performance is also improved as follows. Reduced weight through: elimination of the plastic cell container; elimination of plate leads and intercell connector; and elimination of internal plate current collector. Increased voltage through: elimination of resistance of current collector; elimination of resistance of plate lead; and elimination of resistance of intercell connector. EPI worked previously on development of a secondary bipolar silver zinc battery. This development demonstrated the electrical capability of the system and manufacturing techniques. One difficulty with this development was mechanical problems with the seals. However, recent improvements in plastics and adhesives should eliminate the major problem of maintaining a seal around the periphery of the bipolar module. The seal problem is not as significant for a primary battery application or for a requirement for only a few discharge cycles. A second difficulty encountered was with activation (introducing electrolyte into the cell) and with venting gas from the cell without loss of electrolyte. During previous work, the following projections for energy density were made from test data for a high power system which demonstrated in excess of 50 discharge/charge cycles. Projected system power = 100 kilowatts; discharge time = 30 seconds; discharge current density = 1.75 amps/sq in.; system weight = 86 lbs (9.7 WH/lb); and system volume = 1071 cu. in. (.78 WH/cu. in.). EPI is currently working on a development program to produce a bipolar silver-zinc battery design for NASA. The potential application would be to power electromechanical actuators for space launch vehicles.

  15. Design and simulation of novel flow field plate geometry for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Ruan, Hanxia; Wu, Chaoqun; Liu, Shuliang; Chen, Tao

    2016-10-01

    Bipolar plate is one of the many important components of proton exchange membrane fuel cell (PEMFC) stacks as it supplies fuel and oxidant to the membrane-electrode assembly (MEA), removes water, collects produced current and provides mechanical support for the single cells in the stack. The flow field design of a bipolar plate greatly affects the performance of a PEMFC. It must uniformly distribute the reactant gases over the MEA and prevent product water flooding. This paper aims at improving the fuel cell performance by optimizing flow field designs and flow channel configurations. To achieve this, a novel biomimetic flow channel for flow field designs is proposed based on Murray's Law. Computational fluid dynamics based simulations were performed to compare three different designs (parallel, serpentine and biomimetic channel, respectively) in terms of current density distribution, power density distribution, pressure distribution, temperature distribution, and hydrogen mass fraction distribution. It was found that flow field designs with biomimetic flow channel perform better than that with convectional flow channel under the same operating conditions.

  16. A micro-CL system and its applications

    NASA Astrophysics Data System (ADS)

    Wei, Zenghui; Yuan, Lulu; Liu, Baodong; Wei, Cunfeng; Sun, Cuili; Yin, Pengfei; Wei, Long

    2017-11-01

    The computed laminography (CL) method is preferable to computed tomography for the non-destructive testing of plate-like objects. A micro-CL system is developed for three-dimensional imaging of plate-like objects. The details of the micro-CL system are described, including the system architecture, scanning modes, and reconstruction algorithm. The experiment results of plate-like fossils, insulated gate bipolar translator module, ball grid array packaging, and printed circuit board are also presented to demonstrate micro-CL's ability for 3D imaging of flat specimens and universal applicability in various fields.

  17. A micro-CL system and its applications.

    PubMed

    Wei, Zenghui; Yuan, Lulu; Liu, Baodong; Wei, Cunfeng; Sun, Cuili; Yin, Pengfei; Wei, Long

    2017-11-01

    The computed laminography (CL) method is preferable to computed tomography for the non-destructive testing of plate-like objects. A micro-CL system is developed for three-dimensional imaging of plate-like objects. The details of the micro-CL system are described, including the system architecture, scanning modes, and reconstruction algorithm. The experiment results of plate-like fossils, insulated gate bipolar translator module, ball grid array packaging, and printed circuit board are also presented to demonstrate micro-CL's ability for 3D imaging of flat specimens and universal applicability in various fields.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng

    An electrically conductive laminate composition for fuel cell flow field plate or bipolar plate applications. The laminate composition comprises at least a thin metal sheet having two opposed exterior surfaces and a first exfoliated graphite composite sheet bonded to the first of the two exterior surfaces of the metal sheet wherein the exfoliated graphite composite sheet comprises: (a) expanded or exfoliated graphite and (b) a binder or matrix material to bond the expanded graphite for forming a cohered sheet, wherein the binder or matrix material is between 3% and 60% by weight based on the total weight of the firstmore » exfoliated graphite composite sheet. Preferably, the first exfoliated graphite composite sheet further comprises particles of non-expandable graphite or carbon in the amount of between 3% and 60% by weight based on the total weight of the non-expandable particles and the expanded graphite. Further preferably, the laminate comprises a second exfoliated graphite composite sheet bonded to the second surface of the metal sheet to form a three-layer laminate. Surface flow channels and other desired geometric features can be built onto the exterior surfaces of the laminate to form a flow field plate or bipolar plate. The resulting laminate has an exceptionally high thickness-direction conductivity and excellent resistance to gas permeation.« less

  19. Fuel cell with metal screen flow-field

    DOEpatents

    Wilson, M.S.; Zawodzinski, C.

    1998-08-25

    A polymer electrolyte membrane (PEM) fuel cell is provided with electrodes supplied with a reactant on each side of a catalyzed membrane assembly (CMA). The fuel cell includes a metal mesh defining a rectangular flow-field pattern having an inlet at a first corner and an outlet at a second corner located on a diagonal from the first corner, wherein all flow paths from the inlet to the outlet through the square flow field pattern are equivalent to uniformly distribute the reactant over the CMA. In a preferred form of metal mesh, a square weave screen forms the flow-field pattern. In a particular characterization of the present invention, a bipolar plate electrically connects adjacent fuel cells, where the bipolar plate includes a thin metal foil having an anode side and a cathode side; a first metal mesh on the anode side of the thin metal foil; and a second metal mesh on the cathode side of the thin metal foil. In another characterization of the present invention, a cooling plate assembly cools adjacent fuel cells, where the cooling plate assembly includes an anode electrode and a cathode electrode formed of thin conducting foils; and a metal mesh flow field there between for distributing cooling water flow over the electrodes to remove heat generated by the fuel cells. 11 figs.

  20. Fuel cell with metal screen flow-field

    DOEpatents

    Wilson, Mahlon S.; Zawodzinski, Christine

    2001-01-01

    A polymer electrolyte membrane (PEM) fuel cell is provided with electrodes supplied with a reactant on each side of a catalyzed membrane assembly (CMA). The fuel cell includes a metal mesh defining a rectangular flow-field pattern having an inlet at a first corner and an outlet at a second corner located on a diagonal from the first corner, wherein all flow paths from the inlet to the outlet through the square flow field pattern are equivalent to uniformly distribute the reactant over the CMA. In a preferred form of metal mesh, a square weave screen forms the flow-field pattern. In a particular characterization of the present invention, a bipolar plate electrically connects adjacent fuel cells, where the bipolar plate includes a thin metal foil having an anode side and a cathode side; a first metal mesh on the anode side of the thin metal foil; and a second metal mesh on the cathode side of the thin metal foil. In another characterization of the present invention, a cooling plate assembly cools adjacent fuel cells, where the cooling plate assembly includes an anode electrode and a cathode electrode formed of thin conducting foils; and a metal mesh flow field therebetween for distributing cooling water flow over the electrodes to remove heat generated by the fuel cells.

  1. Fuel cell with metal screen flow-field

    DOEpatents

    Wilson, Mahlon S.; Zawodzinski, Christine

    1998-01-01

    A polymer electrolyte membrane (PEM) fuel cell is provided with electrodes supplied with a reactant on each side of a catalyzed membrane assembly (CMA). The fuel cell includes a metal mesh defining a rectangular flow-field pattern having an inlet at a first corner and an outlet at a second corner located on a diagonal from the first corner, wherein all flow paths from the inlet to the outlet through the square flow field pattern are equivalent to uniformly distribute the reactant over the CMA. In a preferred form of metal mesh, a square weave screen forms the flow-field pattern. In a particular characterization of the present invention, a bipolar plate electrically connects adjacent fuel cells, where the bipolar plate includes a thin metal foil having an anode side and a cathode side; a first metal mesh on the anode side of the thin metal foil; and a second metal mesh on the cathode side of the thin metal foil. In another characterization of the present invention, a cooling plate assembly cools adjacent fuel cells, where the cooling plate assembly includes an anode electrode and a cathode electrode formed of thin conducting foils; and a metal mesh flow field therebetween for distributing cooling water flow over the electrodes to remove heat generated by the fuel cells.

  2. Anodic Behaviour of High Nitrogen-Bearing Steel in PEMFC Environments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, H.; Turner, J. A.

    2008-02-01

    High nitrogen-bearing stainless steels, AISI Type 201 and AL219, were investigated in simulated polymer electrolyte membrane fuel cell (PEMFC) environments to assess the use of these materials in fuel cell bipolar plate applications. Both steels exhibit better corrosion behavior than 316L steel in the same environments. Type 201 steel shows similar but lower interfacial contact resistance (ICR) than 316L, while AL219 steel shows higher ICR than 316L. X-ray photoelectron spectroscopy (XPS) analysis shows that the air-formed films on Type 201 and AL219 are composed of iron oxides, chromium oxide, and manganese oxide. Iron oxides dominate the composition of the air-formedmore » film, specially the outer layer. Chromium oxide dominates passive films. Surface film thicknesses were estimated. The results suggest that high nitrogen-bearing stainless steels are promising materials for PEMFC bipolar plates.« less

  3. Surface modified stainless steels for PEM fuel cell bipolar plates

    DOEpatents

    Brady, Michael P [Oak Ridge, TN; Wang, Heli [Littleton, CO; Turner, John A [Littleton, CO

    2007-07-24

    A nitridation treated stainless steel article (such as a bipolar plate for a proton exchange membrane fuel cell) having lower interfacial contact electrical resistance and better corrosion resistance than an untreated stainless steel article is disclosed. The treated stainless steel article has a surface layer including nitrogen-modified chromium-base oxide and precipitates of chromium nitride formed during nitridation wherein oxygen is present in the surface layer at a greater concentration than nitrogen. The surface layer may further include precipitates of titanium nitride and/or aluminum oxide. The surface layer in the treated article is chemically heterogeneous surface rather than a uniform or semi-uniform surface layer exclusively rich in chromium, titanium or aluminum. The precipitates of titanium nitride and/or aluminum oxide are formed by the nitriding treatment wherein titanium and/or aluminum in the stainless steel are segregated to the surface layer in forms that exhibit a low contact resistance and good corrosion resistance.

  4. Iron-based alloy and nitridation treatment for PEM fuel cell bipolar plates

    DOEpatents

    Brady, Michael P [Oak Ridge, TN; Yang, Bing [Oak Ridge, TN; Maziasz, Philip J [Oak Ridge, TN

    2010-11-09

    A corrosion resistant electrically conductive component that can be used as a bipolar plate in a PEM fuel cell application is composed of an alloy substrate which has 10-30 wt. % Cr, 0.5 to 7 wt. % V, and base metal being Fe, and a continuous surface layer of chromium nitride and vanadium nitride essentially free of base metal. A oxide layer of chromium vanadium oxide can be disposed between the alloy substrate and the continuous surface nitride layer. A method to prepare the corrosion resistant electrically conductive component involves a two-step nitridization sequence by exposing the alloy to a oxygen containing gas at an elevated temperature, and subsequently exposing the alloy to an oxygen free nitrogen containing gas at an elevated temperature to yield a component where a continuous chromium nitride layer free of iron has formed at the surface.

  5. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Selamat, Mohd Zulkefli, E-mail: azulkeflis@utem.edu.my; Yusuf, Muhammad Yusri Md, E-mail: yusri.cheras@gmail.com; Wer, Tio Kok, E-mail: to91@hotmail.my

    Bipolar plates are key components in Proton Exchange Membrane (PEM) fuel cells. They carry current away from the cell and withstand the clamping force of the stack assembly. Therefore, PEM fuel cell bipolar plates must have high electrical conductivity and adequate mechanical strength, in addition to being light weight and low cost in terms of both applicable materials and production methods. In this research, the raw materials used to fabricate the high performance bipolar plate are Graphite (Gr), Stannum (Sn) and Polypropylene (PP). All materials used was in powder form and Gr and Sn act as fillers and the PPmore » acts as binder. The ratio of fillers (Gr/Sn) and binder (PP) was fixed at 80:20. For the multi-conductive filler, small amount of Sn, which is 10 up to 20wt% (from the total weight of fillers 80%) have been added into Gr/Sn/PP composite. The fillers were mixed by using the ball mill machine. The second stage of mixing process between the mixer of fillers and binder is also carried out by using ball mill machine before the compaction process by the hot press machine. The effect of formation temperatures (160°C-170°C) on the properties of Gr/Sn/PP composite had been studied in detail, especially the electrical conductivity, bulk density, hardness and microstructure analysis of Gr/Sn/PP composite. The result shows that there are significant improvement in the electrical conductivity and bulk density, which are exceeding the US-DoE target with the maximum value of 265.35 S/cm and 1.682g/cm{sup 3} respectively.« less

  6. Bipolar disorder type I and II show distinct relationships between cortical thickness and executive function.

    PubMed

    Abé, C; Rolstad, S; Petrovic, P; Ekman, C-J; Sparding, T; Ingvar, M; Landén, M

    2018-06-15

    Frontal cortical abnormalities and executive function impairment co-occur in bipolar disorder. Recent studies have shown that bipolar subtypes differ in the degree of structural and functional impairments. The relationships between cognitive performance and cortical integrity have not been clarified and might differ across patients with bipolar disorder type I, II, and healthy subjects. Using a vertex-wise whole-brain analysis, we investigated how cortical integrity, as measured by cortical thickness, correlates with executive performance in patients with bipolar disorder type I, II, and controls (N = 160). We found focal associations between executive function and cortical thickness in the medial prefrontal cortex in bipolar II patients and controls, but not in bipolar I disorder. In bipolar II patients, we observed additional correlations in lateral prefrontal and occipital regions. Our findings suggest that bipolar disorder patients show altered structure-function relationships, and importantly that those relationships may differ between bipolar subtypes. The findings are line with studies suggesting subtype-specific neurobiological and cognitive profiles. This study contributes to a better understanding of brain structure-function relationships in bipolar disorder and gives important insights into the neuropathophysiology of diagnostic subtypes. © 2018 The Authors Acta Psychiatrica Scandinavica Published by John Wiley & Sons Ltd.

  7. Progressive neurostructural changes in adolescent and adult patients with bipolar disorder.

    PubMed

    Lisy, Megan E; Jarvis, Kelly B; DelBello, Melissa P; Mills, Neil P; Weber, Wade A; Fleck, David; Strakowski, Stephen M; Adler, Caleb M

    2011-06-01

    Several lines of evidence suggest that bipolar disorder is associated with progressive changes in gray matter volume (GMV), particularly in brain structures involved in emotional regulation and expression. The majority of these studies however, have been cross-sectional in nature. In this study we compared baseline and follow-up scans in groups of bipolar disorder and healthy subjects. We hypothesized bipolar disorder subjects would demonstrate significant GMV changes over time. A total of 58 bipolar disorder and 48 healthy subjects participated in structural magnetic resonance imaging (MRI). Subjects were rescanned 3-34 months after their baseline MRI. MRI images were segmented, normalized to standard stereotactic space, and compared voxel-by-voxel using statistical parametrical mapping software (SPM2). A model was developed to investigate differences in GMV at baseline, and associated with time and episodes, as well as in comparison to healthy subjects. We observed increases in GMV in bipolar disorder subjects across several brain regions at baseline and over time, including portions of the prefrontal cortex as well as limbic and subcortical structures. Time-related changes differed to some degree between adolescent and adult bipolar disorder subjects. The interval between scans positively correlated with GMV increases in bipolar disorder subjects in portions of the prefrontal cortex, and both illness duration and number of depressive episodes were associated with increased GMV in subcortical and limbic structures. Our findings support suggestions that widely observed progressive neurofunctional changes in bipolar disorder patients may be related to structural brain abnormalities in anterior limbic structures. Abnormalities largely involve regions previously noted to be integral to emotional expression and regulation, and appear to vary by age. © 2011 John Wiley and Sons A/S.

  8. Meta-Analysis of Amygdala Volumes in Children and Adolescents with Bipolar Disorder

    ERIC Educational Resources Information Center

    Pfeifer, Jonathan C.; Welge, Jeffrey; Strakowski. Stephen M.; Adler, Caleb M.; Delbello, Melissa P.

    2008-01-01

    The size of amygdala of bipolar youths and adults is investigated using neuroimaging studies. Findings showed that smaller volumes of amygdala were observed in youths with bipolar youths compared with children and adolescents without bipolar disorder. The structural amygdala abnormalities in bipolar youths are examined further.

  9. Bipolar battery plate

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1987-01-01

    A liquid-impermeable plate (10) having through-plate conductivity with essentially zero resistance comprises an insulator sheet (12) having a series of spaced perforations (14) each of which contains a metal element (16) sealingly received into the perforation (14). A low-cost plate can readily be manufactured by punching a thermoplastic sheet (40) such as polypropylene with a punching tool (52), filling the apertures with led spheres (63) having a diameter smaller than the holes (50) but larger than the thickness of the sheet, sweeping excess spheres (62) off the sheet with a doctor blade (60) and then pressing a heated platen (74) onto the sheet to swage the spheres into a cylindrical shape and melt the surrounding resin to form a liquid-impermeable collar (4) sealing the metal into the sheet.

  10. Fuel cell plates with improved arrangement of process channels for enhanced pressure drop across the plates

    DOEpatents

    Spurrier, Francis R.; Pierce, Bill L.; Wright, Maynard K.

    1986-01-01

    A plate for a fuel cell has an arrangement of ribs defining an improved configuration of process gas channels and slots on a surface of the plate which provide a modified serpentine gas flow pattern across the plate surface. The channels are generally linear and arranged parallel to one another while the spaced slots allow cross channel flow of process gas in a staggered fashion which creates a plurality of generally mini-serpentine flow paths extending transverse to the longitudinal gas flow along the channels. Adjacent pairs of the channels are interconnected to one another in flow communication. Also, a bipolar plate has the aforementioned process gas channel configuration on one surface and another configuration on the opposite surface. In the other configuration, there are not slots and the gas flow channels have a generally serpentine configuration.

  11. Thermal conductivity of a graphite bipolar plate (BPP) and its thermal contact resistance with fuel cell gas diffusion layers: Effect of compression, PTFE, micro porous layer (MPL), BPP out-of-flatness and cyclic load

    NASA Astrophysics Data System (ADS)

    Sadeghifar, Hamidreza; Djilali, Ned; Bahrami, Majid

    2015-01-01

    This paper reports on measurements of thermal conductivity of a graphite bipolar plate (BPP) as a function of temperature and its thermal contact resistance (TCR) with treated and untreated gas diffusion layers (GDLs). The thermal conductivity of the BPP decreases with temperature and its thermal contact resistance with GDLs, which has been overlooked in the literature, is found to be dominant over a relatively wide range of compression. The effects of PTFE loading, micro porous layer (MPL), compression, and BPP out-of-flatness are also investigated experimentally. It is found that high PTFE loadings, MPL and even small BPP out-of-flatness increase the BPP-GDL thermal contact resistance dramatically. The paper also presents the effect of cyclic load on the total resistance of a GDL-BPP assembly, which sheds light on the behavior of these materials under operating conditions in polymer electrolyte membrane fuel cells.

  12. Defective neuronal migration and inhibition of bipolar to multipolar transition of migrating neural cells by Mesoderm-Specific Transcript, Mest, in the developing mouse neocortex.

    PubMed

    Ji, Liting; Bishayee, Kausik; Sadra, Ali; Choi, Seunghyuk; Choi, Wooyul; Moon, Sungho; Jho, Eek-Hoon; Huh, Sung-Oh

    2017-07-04

    Brain developmental disorders such as lissencephaly can result from faulty neuronal migration and differentiation during the formation of the mammalian neocortex. The cerebral cortex is a modular structure, where developmentally, newborn neurons are generated as a neuro-epithelial sheet and subsequently differentiate, migrate and organize into their final positions in the cerebral cortical plate via a process involving both tangential and radial migration. The specific role of Mest, an imprinted gene, in neuronal migration has not been previously studied. In this work, we reduced expression of Mest with in utero electroporation of neuronal progenitors in the developing embryonic mouse neocortex. Reduction of Mest levels by shRNA significantly reduced the number of neurons migrating to the cortical plate. Also, Mest-knockdown disrupted the transition of bipolar neurons into multipolar neurons migrating out of the sub-ventricular zone region. The migrating neurons also adopted a more tangential migration pattern upon knockdown of the Mest message, losing their potential to attach to radial glia cells, required for radial migration. The differentiation and migration properties of neurons via Wnt-Akt signaling were affected by Mest changes. In addition, miR-335, encoded in a Mest gene intron, was identified as being responsible for blocking the default tangential migration of the neurons. Our results suggest that Mest and its intron product, miR-335, play important roles in neuronal migration with Mest regulating the morphological transition of primary neurons required in the formation of the mammalian neocortex. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. Miniature electrometer preamplifier effectively compensates for input capacitance

    NASA Technical Reports Server (NTRS)

    Burrous, C. N.; Deboo, G. J.

    1966-01-01

    Negative capacitance preamplifier using a dual MOS /Metal Oxide Silicon/ transistor in conjunction with bipolar transistors is used with intracellular microelectrodes in recording bioelectric potentials. Applications would include use as a pickup plate video amplifier in storage tube tests and for pH and ionization chamber measurements.

  14. An investigation of the typical corrosion parameters used to test polymer electrolyte fuel cell bipolar plate coatings, with titanium nitride coated stainless steel as a case study

    NASA Astrophysics Data System (ADS)

    Orsi, A.; Kongstein, O. E.; Hamilton, P. J.; Oedegaard, A.; Svenum, I. H.; Cooke, K.

    2015-07-01

    Stainless steel bipolar plates (BPP) for polymer electrolyte membrane fuel cells (PEMFCs) have good manufacturability, durability and low costs, but inadequate corrosion resistance and elevated interfacial contact resistance (ICR) in the fuel cell environment. Thin film coatings of titanium nitride (TiN) of 1 μm in thickness, were deposited by means of physical vapour deposition (PVD) process on to stainless steel (SS) 316L substrates and were evaluated, in a series of tests, for their level of corrosion protection and ICR. In the ex-situ corrosion tests, variables such as applied potential, experimental duration and pH of the sulphate electrolyte at 80 °C were altered. The ICR values were found to increase after exposure to greater applied potentials and electrolytes of a higher pH. In terms of experimental duration, the ICR increased most rapidly at the beginning of each experiment. It was also found that the oxidation of TiN was accelerated after exposure to electrolytes of a higher pH. When coated BPPs were incorporated into an accelerated fuel cell test, the degradation of the fuel cell cathode resembled the plates that were tested at the highest anodic potential (1.4 VSHE).

  15. Investigation of the effects of process sequence on the contact resistance characteristics of coated metallic bipolar plates for polymer electrolyte membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Turan, Cabir; Cora, Ömer Necati; Koç, Muammer

    2013-12-01

    In this study, results of an investigation on the effects of manufacturing and coating process sequence on the contact resistance (ICR) of metallic bipolar plates (BPP) for polymer electrolyte membrane fuel cells (PEMFCs) are presented. Firstly, uncoated stainless steel 316L blanks were formed into BPP through hydroforming and stamping processes. Then, these formed BPP samples were coated with three different PVD coatings (CrN, TiN and ZrN) at three different thicknesses (0.1, 0.5 and 1 μm). Secondly, blanks of the same alloy were coated first with the same coatings, thickness and technique; then, they were formed into BPPs of the same shape and dimensions using the manufacturing methods as in the first group. Finally, these two groups of BPP samples were tested for their ICR to reveal the effect of process sequence. ICR tests were also conducted on the BPP plates both before and after exposure to corrosion to disclose the effect of corrosion on ICR. Coated-then-formed BPP samples exhibited similar or even better ICR performance than formed-then-coated BPP samples. Thus, manufacturing of coated blanks can be concluded to be more favorable and worth further investigation in quest of making cost effective BPPs for mass production of PEMFC.

  16. The thermodynamics of bipolarity: a bifurcation model of bipolar illness and bipolar character and its psychotherapeutic applications.

    PubMed

    Sabelli, H C; Carlson-Sabelli, L; Javaid, J I

    1990-11-01

    Two models dominate current formulations of bipolar illness: the homeostatic model implicit in Freud's psychodynamics and most neuroamine deficit/excess theories; and the oscillatory model of exaggerated biological rhythms. The homeostatic model is based on the closed systems approach of classic thermodynamics, while the oscillatory model requires the open systems approach of modern thermodynamics. Here we present a thermodynamic model of bipolarity that includes both homeostatic and oscillatory features and adds the most important feature of open systems thermodynamics: the creation of novel structures in bifurcation processes. According to the proposed model, bipolarity is the result of exaggerated biological energy that augments homeostatic, oscillatory and creative psychological processes. Only low-energy closed systems tend to rest ("point attractor") and entropic disorder. Open processes containing and exchanging energy fluctuate between opposite states ("periodic attractors"); they are characteristic of most physiological rhythms and are exaggerated in bipolar subjects. At higher energies, their strong fluctuations destroy pre-existing patterns and structures, produce turbulence ("chaotic attractors"), which sudden switches between opposite states, and create new and more complex structures. Likewise, high-energy bipolars develop high spontaneity, great fluctuations between opposite moods, internal and interpersonal chaos, and enhanced creativity (personal, artistic, professional) as well as psychopathology (personality deviations, psychotic delusions). Offered here is a theoretical explanation of the dual--creative and destructive--nature of bipolarity in terms of the new enantiodromic concept of entropy generalized by process theory. Clinically, this article offers an integrative model of bipolarity that accounts for many clinical features and contributes to a definition of the bipolar personality.

  17. Factor analysis of regional brain activation in bipolar and healthy individuals reveals a consistent modular structure.

    PubMed

    Fleck, David E; Welge, Jeffrey A; Eliassen, James C; Adler, Caleb M; DelBello, Melissa P; Strakowski, Stephen M

    2018-07-01

    The neurophysiological substrates of cognition and emotion, as seen with fMRI, are generally explained using modular structures. The present study was designed to probe the modular structure of cognitive-emotional processing in bipolar and healthy individuals using factor analysis and compare the results with current conceptions of the neurophysiology of bipolar disorder. Exploratory factor analysis was used to assess patterns of covariation among brain regions-of-interest activated during the Continuous Performance Task with Emotional and Neutral Distractors in healthy and bipolar individuals without a priori constraints on the number or composition of latent factors. Results indicated a common cognitive-emotional network consisting of prefrontal, medial temporal, limbic, parietal, anterior cingulate and posterior cingulate modules. However, reduced brain activation to emotional stimuli in the frontal, medial temporal and limbic modules was apparent in the bipolar relative to the healthy group, potentially accounting for emotional dysregulation in bipolar disorder. This study is limited by a relatively small sample size recruited at a single site. The results have yet to be validated on a larger independent sample. Although the modular structure of cognitive-emotional processing is similar in bipolar and healthy individuals, activation in response to emotional/neutral cues varies. These findings are not only consistent with recent conceptions of mood regulation in bipolar disorder, but also suggest that regional activation can be considered within tighter modular structures without compromising data interpretation. This demonstration may serve as a template for data reduction in future region-of-interest analyses to increase statistical power. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. The bipolar silicon microstrip detector: A proposal for a novel precision tracking device

    NASA Astrophysics Data System (ADS)

    Horisberger, R.

    1990-03-01

    It is proposed to combine the technology of fully depleted silicon microstrip detectors fabricated on n doped high resistivity silicon with the concept of the bipolar transistor. This is done by adding a n ++ doped region inside the normal p + implanted region of the reverse biased p + n diode. Teh resulting structure has amplifying properties and is referred to as bipolar pixel transistor. The simplest readout scheme of a bipolar pixel array by an aluminium strip bus leads to the bipolar microstrip detector. The bipolar pixel structure is expected to give a better signal-to-noise performance for the detection of minimum ionizing charged particle tracks than the normal silicon diode strip detector and therefore should allow in future the fabrication of thinner silicon detectors for precision tracking.

  19. Association between childhood dimensions of attention deficit hyperactivity disorder and adulthood clinical severity of bipolar disorders.

    PubMed

    Etain, Bruno; Lajnef, M; Loftus, J; Henry, C; Raust, A; Gard, S; Kahn, J P; Leboyer, M; Scott, J; Bellivier, F

    2017-04-01

    Clinical features of attention deficit hyperactivity disorder can be frequently observed in cases with bipolar disorders and associated with greater severity of bipolar disorders. Although designed as a screening tool for attention deficit hyperactivity disorder, the Wender Utah Rating Scale could, given its factorial structure, be useful in investigating the early history of impulsive, inattentive or mood-related symptoms among patients with bipolar disorders. We rated the Wender Utah Rating Scale in 276 adult bipolar disorder cases and 228 healthy controls and tested its factorial structure and any associations with bipolar disorder phenomenology. We confirmed a three-factor structure for the Wender Utah Rating Scale (' impulsivity/temper', ' inattentiveness' and ' mood/self-esteem'). Cases and controls differed significantly on Wender Utah Rating Scale total score and sub-scale scores ( p-values < 10 -5 ). About 23% of bipolar disorder cases versus 5% of controls were classified as ' WURS positive' (odds ratio = 5.21 [2.73-9.95]). In bipolar disorders, higher Wender Utah Rating Scale score was associated with earlier age at onset, severity of suicidal behaviors and polysubstance misuse; multivariate analyses, controlling for age and gender, confirmed the associations with age at onset ( p = 0.001) and alcohol and substance misuse ( p = 0.001). Adults with bipolar disorders who reported higher levels of childhood symptoms on the Wender Utah Rating Scale presented a more severe expression of bipolar disorders in terms of age at onset and comorbidity. The Wender Utah Rating Scale could be employed to screen for attention deficit hyperactivity disorder but also for ' at-risk behaviors' in adult bipolar disorder cases and possibly for prodromal signs of early onset in high-risk subjects.

  20. Differential pattern of semantic memory organization between bipolar I and II disorders.

    PubMed

    Chang, Jae Seung; Choi, Sungwon; Ha, Kyooseob; Ha, Tae Hyon; Cho, Hyun Sang; Choi, Jung Eun; Cha, Boseok; Moon, Eunsoo

    2011-06-01

    Semantic cognition is one of the key factors in psychosocial functioning. The aim of this study was to explore the differences in pattern of semantic memory organization between euthymic patients with bipolar I and II disorders using the category fluency task. Study participants included 23 euthymic subjects with bipolar I disorder, 23 matched euthymic subjects with bipolar II disorder and 23 matched control subjects. All participants were assessed for verbal learning, recall, learning strategies, and fluency. The combined methods of hierarchical clustering and multidimensional scaling were used to compare the pattern of semantic memory organization among the three groups. Quantitative measures of verbal learning, recall, learning strategies, and fluency did not differ between the three groups. A two-cluster structure of semantic memory organization was identified for the three groups. Semantic structure was more disorganized in the bipolar I disorder group compared to the bipolar II disorder. In addition, patients with bipolar II disorder used less elaborate strategies of semantic memory organization than those of controls. Compared to healthy controls, strategies for categorization in semantic memory appear to be less knowledge-based in patients with bipolar disorders. A differential pattern of semantic memory organization between bipolar I and II disorders indicates a higher risk of cognitive abnormalities in patients with bipolar I disorder compared to patients with bipolar II disorder. Exploring qualitative nature of neuropsychological domains may provide an explanatory insight into the characteristic behaviors of patients with bipolar disorders. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Conductive and corrosion behaviors of silver-doped carbon-coated stainless steel as PEMFC bipolar plates

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Xu, Hong-feng; Fu, Jie; Tian, Ying

    2016-07-01

    Ni-Cr enrichment on stainless steel SS316L resulting from chemical activation enabled the deposition of carbon by spraying a stable suspension of carbon nanoparticles; trace Ag was deposited in situ to prepare a thin continuous Ag-doped carbon film on a porous carbon-coated SS316L substrate. The corrosion resistance of this film in 0.5 mol·L-1 H2SO4 solution containing 5 ppm F- at 80°C was investigated using polarization tests. The results showed that the surface treatment of the SS316L strongly affected the adhesion of the carbon coating to the stainless steel. Compared to the bare SS316L, the Ag-doped carbon-coated SS316L bipolar plate was remarkably more stable in both the anode and cathode environments of proton exchange membrane fuel cell (PEMFC) and the interface contact resistance between the specimen and Toray 060 carbon paper was reduced from 333.0 mΩ·cm2 to 21.6 mΩ·cm2 at a compaction pressure of 1.2 MPa.

  2. Impact of heat and water management on proton exchange membrane fuel cells degradation in automotive application

    NASA Astrophysics Data System (ADS)

    Nandjou, F.; Poirot-Crouvezier, J.-P.; Chandesris, M.; Blachot, J.-F.; Bonnaud, C.; Bultel, Y.

    2016-09-01

    In Proton Exchange Membrane Fuel Cells, local temperature is a driving force for many degradation mechanisms such as hygrothermal deformation and creep of the membrane, platinum dissolution and bipolar plates corrosion. In order to investigate and quantify those effects in automotive application, durability testing is conducted in this work. During the ageing tests, the local performance and temperature are investigated using in situ measurements of a printed circuit board. At the end of life, post-mortem analyses of the aged components are conducted. The experimental results are compared with the simulated temperature and humidity in the cell obtained from a pseudo-3D multiphysics model in order to correlate the observed degradations to the local conditions inside the stack. The primary cause of failure in automotive cycling is pinhole/crack formation in the membrane, induced by high variations of its water content over time. It is also observed that water condensation largely increases the probability of the bipolar plates corrosion while evaporation phenomena induce local deposits in the cell.

  3. Probing Formability Improvement of Ultra-thin Ferritic Stainless Steel Bipolar Plate of PEMFC in Non-conventional Forming Process

    NASA Astrophysics Data System (ADS)

    Bong, Hyuk Jong; Barlat, Frédéric; Lee, Myoung-Gyu

    2016-08-01

    Formability increase in non-conventional forming profiles programmed in the servo-press was investigated using finite element analysis. As an application, forming experiment on a 0.15-mm-thick ferritic stainless steel sheet for a bipolar plate, a primary component of a proton exchange membrane fuel cell, was conducted. Four different forming profiles were considered to investigate the effects of forming profiles on formability and shape accuracy. The four motions included conventional V motion, holding motion, W motion, and oscillating motion. Among the four motions, the holding motion, in which the slide was held for a certain period at the bottom dead point, led to the best formability. Finite element simulations were conducted to validate the experimental results and to probe the formability improvement in the non-conventional forming profiles. A creep model to address stress relaxation effect along with tool elastic recovery was implemented using a user-material subroutine, CREEP in ABAQUS finite element software. The stress relaxation and variable contact conditions during the holding and oscillating profiles were found to be the main mechanism of formability improvement.

  4. Bipolar battery plate

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1985-01-01

    A liquid-impermeable plate (10) having throughplate conductivity with essentially zero resistance comprises an insulator sheet (12) having a series of spaced perforations (14) each of which contains a metal element (16) sealingly received into the perforation (14). A low-cost plate can readily be manufactured by punching a thermoplastic sheet (40) such as polypropylene with a punching tool (52), filling the apertures with lead spheres (63) having a diameter smaller than the holes (50) but larger than the thickness of the sheet, sweeping excess spheres (62) off the sheet with a doctor blade (60) and then pressing a heated platen (74) onto the sheet to swage the spheres into a cylindrical shape and melt the surrounding resin to form a liquid-impermeable collar (4) sealing the metal into the sheet.

  5. Electric field with bipolar structure during magnetic reconnection without a guide field

    NASA Astrophysics Data System (ADS)

    Guo, Jun

    2014-05-01

    We present a study on the polarized electric field during the collisionless magnetic reconnection of antiparallel fields using two dimensional particle-in-cell simulations. The simulations demonstrate clearly that electron holes and electric field with bipolar structure are produced during magnetic reconnection without a guide field. The electric field with bipolar structure can be found near the X-line and on the separatrix and the plasma sheet boundary layer, which is consistent with the observations. These structures will elongate electron's time staying in the diffusion region. In addition, the electric fields with tripolar structures are also found in our simulation.

  6. BDNF and BMI effects on brain structures of bipolar offspring: results from the global mood and brain science initiative.

    PubMed

    Mansur, R B; Brietzke, E; McIntyre, R S; Cao, B; Lee, Y; Japiassú, L; Chen, K; Lu, R; Lu, W; Li, T; Xu, G; Lin, K

    2017-12-01

    To compare brain-derived neurotrophic factor (BDNF) levels between offspring of individuals with bipolar disorders (BD) and healthy controls (HCs) and investigate the effects of BDNF levels and body mass index (BMI) on brain structures. Sixty-seven bipolar offspring and 45 HCs were included (ages 8-28). Structural images were acquired using 3.0 Tesla magnetic resonance imaging. Serum BDNF levels were measured using enzyme-linked immunosorbent assay. Multivariate and univariate analyses of covariance were conducted. Significantly higher BDNF levels were observed among bipolar offspring, relative to HCs (P > 0.025). Offspring status moderated the association between BDNF and BMI (F 1 =4.636, P = 0.034). After adjustment for relevant covariates, there was a trend for a significant interaction of group and BDNF on neuroimaging parameters (Wilks'λ F 56,94 =1.463, P = 0.052), with significant effects on cerebellar white matter and superior and middle frontal regions. Brain volume and BDNF were positively correlated among HCs and negatively correlated among bipolar offspring. Interactions between BDNF and BMI on brain volumes were non-significant among HCs (Wilks'λ F 28,2 =2.229, P = 0.357), but significant among bipolar offspring (Wilks'λ F 28,12 =2.899, P = 0.028). Offspring status and BMI moderate the association between BDNF levels and brain structures among bipolar offspring, underscoring BDNF regulation and overweight/obesity as key moderators of BD pathogenesis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Investigations on the corrosion resistance of metallic bipolar plates (BPP) in proton exchange membrane fuel cells (PEMFC) - understanding the effects of material, coating and manufacturing

    NASA Astrophysics Data System (ADS)

    Dur, Ender

    Polymer Electrolyte Membrane Fuel Cell (PEMFC) systems are promising technology for contributing to meet the deficiency of world`s clean and sustainable energy requirements in the near future. Metallic bipolar plate (BPP) as one of the most significant components of PEMFC device accounts for the largest part of the fuel cell`s stack. Corrosion for metallic bipolar plates is a critical issue, which influences the performance and durability of PEMFC. Corrosion causes adverse impacts on the PEMFC`s performance jeopardizing commercialization. This research is aimed at determining the corrosion resistance of metallic BPPs, particularly stainless steels, used in PEMFC from different aspects. Material selection, coating selection, manufacturing process development and cost considerations need to be addressed in terms of the corrosion behavior to justify the use of stainless steels as a BPP material in PEMFC and to make them commercially feasible in industrial applications. In this study, Ti, Ni, SS304, SS316L, and SS 430 blanks, and BPPs comprised of SS304 and SS316L were examined in terms of the corrosion behavior. SS316L plates were coated to investigate the effect of coatings on the corrosion resistance performance. Stamping and hydroforming as manufacturing processes, and three different coatings (TiN, CrN, ZrN) applied via the Physical Vapor Deposition (PVD) method in three different thicknesses were selected to observe the effects of manufacturing processes, coating types and coating thicknesses on the corrosion resistance of BPP, respectively. Uncoated-coated blank and formed BPP were subjected to two different corrosion tests: potentiostatic and potentiodynamic. Some of the substantial results: 1- Manufacturing processes have an adverse impact on the corrosion resistance. 2- Hydroformed plates have slightly higher corrosion resistance than stamped samples. 3- BPPs with higher channel size showed better corrosion resistance. 4- Since none of the uncoated samples meet the 2015 target of the U.S. Department of Energy, surface coating is required. 5- ZrN and CrN coated BPPs exhibited higher corrosion resistance meeting DOE target while TiN coated samples had the lowest corrosion resistance. Higher coating thicknesses improved the corrosion resistance of the BPPs. 6- Process sequence between coating and manufacturing is not significant for hydroforming case (ZrN and CrN) and stamping case (CrN) in terms of the corrosion resistance. In other words, coating the BPP`s substrate material before manufacturing process does not always decrease the corrosion resistance of the BPPs.

  8. Commercial phosphoric acid fuel cell system technology development

    NASA Technical Reports Server (NTRS)

    Prokopius, P. R.; Warshay, M.; Simons, S. N.; King, R. B.

    1979-01-01

    Reducing cost and increasing reliability were the technology drivers in both the electric utility and on-site integrated energy system applications. The longstanding barrier to the attainment of these goals was materials. Differences in approaches and their technological features, including electrodes, matrices, intercell cooling, bipolar/separator plates, electrolyte management, fuel selection, and system design philosophy were discussed.

  9. Brain structural changes in schizoaffective disorder compared to schizophrenia and bipolar disorder.

    PubMed

    Amann, B L; Canales-Rodríguez, E J; Madre, M; Radua, J; Monte, G; Alonso-Lana, S; Landin-Romero, R; Moreno-Alcázar, A; Bonnin, C M; Sarró, S; Ortiz-Gil, J; Gomar, J J; Moro, N; Fernandez-Corcuera, P; Goikolea, J M; Blanch, J; Salvador, R; Vieta, E; McKenna, P J; Pomarol-Clotet, E

    2016-01-01

    Brain structural changes in schizoaffective disorder, and how far they resemble those seen in schizophrenia and bipolar disorder, have only been studied to a limited extent. Forty-five patients meeting DSM-IV and RDC criteria for schizoaffective disorder, groups of patients with 45 matched schizophrenia and bipolar disorder, and 45 matched healthy controls were examined using voxel-based morphometry (VBM). Analyses comparing each patient group with the healthy control subjects found that the patients with schizoaffective disorder and the patients with schizophrenia showed widespread and overlapping areas of significant volume reduction, but the patients with bipolar disorder did not. A subsequent analysis compared the combined group of patients with the controls followed by extraction of clusters. In regions where the patients differed significantly from the controls, no significant differences in mean volume between patients with schizoaffective disorder and patients with schizophrenia in any of five regions of volume reduction were found, but mean volumes in the patients with bipolar disorder were significantly smaller in three of five. The findings provide evidence that, in terms of structural gray matter brain abnormality, schizoaffective disorder resembles schizophrenia more than bipolar disorder. © 2015 The Authors. Acta Psychiatrica Scandinavica Published by John Wiley & Sons Ltd.

  10. Olfactocentric paralimbic cortex morphology in adolescents with bipolar disorder

    PubMed Central

    Wang, Fei; Kalmar, Jessica H.; Womer, Fay Y.; Edmiston, Erin E.; Chepenik, Lara G.; Chen, Rachel; Spencer, Linda

    2011-01-01

    The olfactocentric paralimbic cortex plays a critical role in the regulation of emotional and neurovegetative functions that are disrupted in core features of bipolar disorder. Adolescence is thought to be a critical period in both the maturation of the olfactocentric paralimbic cortex and in the emergence of bipolar disorder pathology. Together, these factors implicate a central role for the olfactocentric paralimbic cortex in the development of bipolar disorder and suggest that abnormalities in this cortex may be expressed by adolescence in the disorder. We tested the hypothesis that differences in olfactocentric paralimbic cortex structure are a morphological feature in adolescents with bipolar disorder. Subjects included 118 adolescents (41 with bipolar disorder and 77 healthy controls). Cortical grey matter volume differences between adolescents with and without bipolar disorder were assessed with voxel-based morphometry analyses of high-resolution structural magnetic resonance imaging scans. Compared with healthy comparison adolescents, adolescents with bipolar disorder demonstrated significant volume decreases in olfactocentric paralimbic regions, including orbitofrontal, insular and temporopolar cortices. Findings in these regions survived small volume correction (P < 0.05, corrected). Volume decreases in adolescents with bipolar disorder were also noted in inferior prefrontal and superior temporal gyri and cerebellum. The findings suggest that abnormalities in the morphology of the olfactocentric paralimbic cortex may contribute to the bipolar disorder phenotype that emerges in adolescence. The morphological development of the olfactocentric paralimbic cortex has received little study. The importance of these cortices in emotional and social development, and support for a central role for these cortices in the development of bipolar disorder, suggest that study of the development of these cortices in health and in bipolar disorder is critically needed. PMID:21666263

  11. Olfactocentric paralimbic cortex morphology in adolescents with bipolar disorder.

    PubMed

    Wang, Fei; Kalmar, Jessica H; Womer, Fay Y; Edmiston, Erin E; Chepenik, Lara G; Chen, Rachel; Spencer, Linda; Blumberg, Hilary P

    2011-07-01

    The olfactocentric paralimbic cortex plays a critical role in the regulation of emotional and neurovegetative functions that are disrupted in core features of bipolar disorder. Adolescence is thought to be a critical period in both the maturation of the olfactocentric paralimbic cortex and in the emergence of bipolar disorder pathology. Together, these factors implicate a central role for the olfactocentric paralimbic cortex in the development of bipolar disorder and suggest that abnormalities in this cortex may be expressed by adolescence in the disorder. We tested the hypothesis that differences in olfactocentric paralimbic cortex structure are a morphological feature in adolescents with bipolar disorder. Subjects included 118 adolescents (41 with bipolar disorder and 77 healthy controls). Cortical grey matter volume differences between adolescents with and without bipolar disorder were assessed with voxel-based morphometry analyses of high-resolution structural magnetic resonance imaging scans. Compared with healthy comparison adolescents, adolescents with bipolar disorder demonstrated significant volume decreases in olfactocentric paralimbic regions, including orbitofrontal, insular and temporopolar cortices. Findings in these regions survived small volume correction (P < 0.05, corrected). Volume decreases in adolescents with bipolar disorder were also noted in inferior prefrontal and superior temporal gyri and cerebellum. The findings suggest that abnormalities in the morphology of the olfactocentric paralimbic cortex may contribute to the bipolar disorder phenotype that emerges in adolescence. The morphological development of the olfactocentric paralimbic cortex has received little study. The importance of these cortices in emotional and social development, and support for a central role for these cortices in the development of bipolar disorder, suggest that study of the development of these cortices in health and in bipolar disorder is critically needed.

  12. Force-balance model of suppression of multipolar division in cancer cells with extra centrosomes

    NASA Astrophysics Data System (ADS)

    Zhu, Jie

    2013-03-01

    Cancer cells often possess extra centrosomes which have the potential to cause cell death due to catastrophic multipolar division. Many cancer cells, however, are able to escape multipolar mitosis by clustering the extra centrosomes to form bipolar spindles. The mechanism of centrosome clustering is therefore of great interest to the development of anti-cancer drugs because the de-clustering of extra centrosomes provides an appealing way to eliminate cancer cells while keeping healthy cells intact. We present a physical model assuming 1) dynamic centrosomal microtubules interact with chromosomes by both pushing on chromosome arms and pulling along kinetochores; 2) these microtubules interact with force generators associated with actin/adhesion structures at the cell boundary; and 3) motors act on anti-parallel microtubules from different centrosomes. We find via computer simulations that chromosomes tend to aggregate near the cell center while centrosomes can be either clustered to form bipolar spindles or scattered to form multipolar spindles, depending on the strengths of relative forces, cell shape and adhesion geometry. The model predictions agree with data from cells plated on adhesive micropatterns and from biochemically or genetically perturbed cells. Furthermore, our model is able to explain various microtubule distributions in interphase cells on patterned substrates. This work was supported by NSF

  13. The validity and internal structure of the Bipolar Depression Rating Scale: data from a clinical trial of N-acetylcysteine as adjunctive therapy in bipolar disorder.

    PubMed

    Berk, Michael; Dodd, Seetal; Dean, Olivia M; Kohlmann, Kristy; Berk, Lesley; Malhi, Gin S

    2010-10-01

    Berk M, Dodd S, Dean OM, Kohlmann K, Berk L, Malhi GS. The validity and internal structure of the Bipolar Depression Rating Scale: data from a clinical trial of N-acetylcysteine as adjunctive therapy in bipolar disorder. The phenomenology of unipolar and bipolar disorders differ in a number of ways, such as the presence of mixed states and atypical features. Conventional depression rating instruments are designed to capture the characteristics of unipolar depression and have limitations in capturing the breadth of bipolar disorder. The Bipolar Depression Rating Scale (BDRS) was administered together with the Montgomery Asberg Rating Scale (MADRS) and Young Mania Rating Scale (YMRS) in a double-blind randomised placebo-controlled clinical trial of N-acetyl cysteine for bipolar disorder (N = 75). A factor analysis showed a two-factor solution: depression and mixed symptom clusters. The BDRS has strong internal consistency (Cronbach's alpha = 0.917), the depression cluster showed robust correlation with the MADRS (r = 0.865) and the mixed subscale correlated with the YMRS (r = 0.750). The BDRS has good internal validity and inter-rater reliability and is sensitive to change in the context of a clinical trial.

  14. Development and validation of a screening instrument for bipolar spectrum disorder: the Mood Disorder Questionnaire.

    PubMed

    Hirschfeld, R M; Williams, J B; Spitzer, R L; Calabrese, J R; Flynn, L; Keck, P E; Lewis, L; McElroy, S L; Post, R M; Rapport, D J; Russell, J M; Sachs, G S; Zajecka, J

    2000-11-01

    Bipolar spectrum disorders, which include bipolar I, bipolar II, and bipolar disorder not otherwise specified, frequently go unrecognized, undiagnosed, and untreated. This report describes the validation of a new brief self-report screening instrument for bipolar spectrum disorders called the Mood Disorder Questionnaire. A total of 198 patients attending five outpatient clinics that primarily treat patients with mood disorders completed the Mood Disorder Questionnaire. A research professional, blind to the Mood Disorder Questionnaire results, conducted a telephone research diagnostic interview by means of the bipolar module of the Structured Clinical Interview for DSM-IV. A Mood Disorder Questionnaire screening score of 7 or more items yielded good sensitivity (0.73) and very good specificity (0.90). The Mood Disorder Questionnaire is a useful screening instrument for bipolar spectrum disorder in a psychiatric outpatient population.

  15. Phosphoric Acid Fuel Cell Technology Status

    NASA Technical Reports Server (NTRS)

    Simons, S. N.; King, R. B.; Prokopius, P. R.

    1981-01-01

    A review of the current phosphoric acid fuel cell system technology development efforts is presented both for multimegawatt systems for electric utility applications and for multikilowatt systems for on-site integrated energy system applications. Improving fuel cell performance, reducing cost, and increasing durability are the technology drivers at this time. Electrodes, matrices, intercell cooling, bipolar/separator plates, electrolyte management, and fuel selection are discussed.

  16. Dry compliant seal for phosphoric acid fuel cell

    DOEpatents

    Granata, Jr., Samuel J.; Woodle, Boyd M.

    1990-01-01

    A dry compliant overlapping seal for a phosphoric acid fuel cell preformed f non-compliant Teflon to make an anode seal frame that encircles an anode assembly, a cathode seal frame that encircles a cathode assembly and a compliant seal frame made of expanded Teflon, generally encircling a matrix assembly. Each frame has a thickness selected to accommodate various tolerances of the fuel cell elements and are either bonded to one of the other frames or to a bipolar or end plate. One of the non-compliant frames is wider than the other frames forming an overlap of the matrix over the wider seal frame, which cooperates with electrolyte permeating the matrix to form a wet seal within the fuel cell that prevents process gases from intermixing at the periphery of the fuel cell and a dry seal surrounding the cell to keep electrolyte from the periphery thereof. The frames may be made in one piece, in L-shaped portions or in strips and have an outer perimeter which registers with the outer perimeter of bipolar or end plates to form surfaces upon which flanges of pan shaped, gas manifolds can be sealed.

  17. Electropolymerization of camphorsulfonic acid doped conductive polypyrrole anti-corrosive coating for 304SS bipolar plates

    NASA Astrophysics Data System (ADS)

    Jiang, Li; Syed, Junaid Ali; Gao, Yangzhi; Zhang, Qiuxiang; Zhao, Junfeng; Lu, Hongbin; Meng, Xiangkang

    2017-12-01

    Conductive polymer coating doped with large molecular organic acid is an alternative method used to protect stainless steel (SS) bipolar plates in proton exchange membrane fuel cells (PEMFCs). However, it is difficult to select the proper doping acid, which improves the corrosion resistance of the coating without affecting its conductivity. In this study, large spatial molecular group camphorsulfonic acid (CSA) doped polypyrrole (PPY) conductive coating was prepared by galvanostatic electropolymerization on 304SS. The electrochemical properties of the coating were evaluated in 0.1 M H2SO4 solution in order to simulate the PEMFC service environment. The results indicate that the coating increased the corrosion potential and shifted Ecorr towards more positive value, particularly the jcorr value of PPY-CSA coated 304SS was dropped from 97.3 to 0.00187 μA cm-2. The long-term immersion tests (660 h) show that the PPY-CSA coating exhibits better corrosion resistance in comparison with the small acid (SO42-) doped PPY-SO42- or PPY/PPY-SO42- coatings. Moreover, the PPY-CSA coating presents low contact resistance and maintains strong corrosion resistance during the prolonged exposure time due to barrier effect and anodic protection.

  18. Fuel cell plates with skewed process channels for uniform distribution of stack compression load

    DOEpatents

    Granata, Jr., Samuel J.; Woodle, Boyd M.

    1989-01-01

    An electrochemical fuel cell includes an anode electrode, a cathode electrode, an electrolyte matrix sandwiched between electrodes, and a pair of plates above and below the electrodes. The plate above the electrodes has a lower surface with a first group of process gas flow channels formed thereon and the plate below the electrodes has an upper surface with a second group of process gas flow channels formed thereon. The channels of each group extend generally parallel to one another. The improvement comprises the process gas flow channels on the lower surface of the plate above the anode electrode and the process gas flow channels on the upper surface of the plate below the cathode electrode being skewed in opposite directions such that contact areas of the surfaces of the plates through the electrodes are formed in crisscross arrangements. Also, the plates have at least one groove in areas of the surfaces thereof where the channels are absent for holding process gas and increasing electrochemical activity of the fuel cell. The groove in each plate surface intersects with the process channels therein. Also, the opposite surfaces of a bipolar plate for a fuel cell contain first and second arrangements of process gas flow channels in the respective surfaces which are skewed the same amount in opposite directions relative to the longitudinal centerline of the plate.

  19. Three-Dimensional Mapping of Hippocampal Anatomy in Adolescents with Bipolar Disorder

    ERIC Educational Resources Information Center

    Bearden, Carrie E.; Soares, Jair C.; Klunder, Andrea D.; Nicoletti, Mark; Dierschki, Nicole; Hayashi, Kiralee M.; Narr, Katherine L.; Bhrambilla, Paolo; Sassi, Roberto B.; Axelson, David; Ryan, Neal; Birmaher, Boris; Thompson, Paul M.

    2008-01-01

    The article discusses the use of three-dimensional mapping methods in children and adolescents with bipolar disorder to find out if localized alterations in hippocampal structure are exhibited. It also explores the developmental differences where the patient with bipolar disorder showed increasing hippocampal size with increasing age.

  20. Brain structure-function associations in multi-generational families genetically enriched for bipolar disorder.

    PubMed

    Fears, Scott C; Schür, Remmelt; Sjouwerman, Rachel; Service, Susan K; Araya, Carmen; Araya, Xinia; Bejarano, Julio; Knowles, Emma; Gomez-Makhinson, Juliana; Lopez, Maria C; Aldana, Ileana; Teshiba, Terri M; Abaryan, Zvart; Al-Sharif, Noor B; Navarro, Linda; Tishler, Todd A; Altshuler, Lori; Bartzokis, George; Escobar, Javier I; Glahn, David C; Thompson, Paul M; Lopez-Jaramillo, Carlos; Macaya, Gabriel; Molina, Julio; Reus, Victor I; Sabatti, Chiara; Cantor, Rita M; Freimer, Nelson B; Bearden, Carrie E

    2015-07-01

    Recent theories regarding the pathophysiology of bipolar disorder suggest contributions of both neurodevelopmental and neurodegenerative processes. While structural neuroimaging studies indicate disease-associated neuroanatomical alterations, the behavioural correlates of these alterations have not been well characterized. Here, we investigated multi-generational families genetically enriched for bipolar disorder to: (i) characterize neurobehavioural correlates of neuroanatomical measures implicated in the pathophysiology of bipolar disorder; (ii) identify brain-behaviour associations that differ between diagnostic groups; (iii) identify neurocognitive traits that show evidence of accelerated ageing specifically in subjects with bipolar disorder; and (iv) identify brain-behaviour correlations that differ across the age span. Structural neuroimages and multi-dimensional assessments of temperament and neurocognition were acquired from 527 (153 bipolar disorder and 374 non-bipolar disorder) adults aged 18-87 years in 26 families with heavy genetic loading for bipolar disorder. We used linear regression models to identify significant brain-behaviour associations and test whether brain-behaviour relationships differed: (i) between diagnostic groups; and (ii) as a function of age. We found that total cortical and ventricular volume had the greatest number of significant behavioural associations, and included correlations with measures from multiple cognitive domains, particularly declarative and working memory and executive function. Cortical thickness measures, in contrast, showed more specific associations with declarative memory, letter fluency and processing speed tasks. While the majority of brain-behaviour relationships were similar across diagnostic groups, increased cortical thickness in ventrolateral prefrontal and parietal cortical regions was associated with better declarative memory only in bipolar disorder subjects, and not in non-bipolar disorder family members. Additionally, while age had a relatively strong impact on all neurocognitive traits, the effects of age on cognition did not differ between diagnostic groups. Most brain-behaviour associations were also similar across the age range, with the exception of cortical and ventricular volume and lingual gyrus thickness, which showed weak correlations with verbal fluency and inhibitory control at younger ages that increased in magnitude in older subjects, regardless of diagnosis. Findings indicate that neuroanatomical traits potentially impacted by bipolar disorder are significantly associated with multiple neurobehavioural domains. Structure-function relationships are generally preserved across diagnostic groups, with the notable exception of ventrolateral prefrontal and parietal association cortex, volumetric increases in which may be associated with cognitive resilience specifically in individuals with bipolar disorder. Although age impacted all neurobehavioural traits, we did not find any evidence of accelerated cognitive decline specific to bipolar disorder subjects. Regardless of diagnosis, greater global brain volume may represent a protective factor for the effects of ageing on executive functioning. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. "Is it menopause or bipolar?": a qualitative study of the experience of menopause for women with bipolar disorder.

    PubMed

    Perich, Tania; Ussher, Jane; Parton, Chloe

    2017-11-16

    Menopause can be a time of change for women and may be marked by disturbances in mood. For women living with a mental illness, such as bipolar disorder, little is known about how they experience mood changes during menopause. This study aimed to explore how women with bipolar disorder constructed mood changes during menopause and how this impacted on treatment decisions. Semi-structured interviews were undertaken with fifteen women who reported they had been diagnosed with bipolar disorder. Data was analysed using thematic analysis guided by a social constructionist framework. Themes identified included 'Constructions of mood change: menopause or bipolar disorder?',' Life events, bipolar disorder and menopause coming together'; 'Treatment choices for mood change during menopause'. The accounts suggested that women related to the experience of mood changes during menopause through the lens of their existing framework of bipolar disorder, with implications for understanding of self and treatment choices.

  2. Inferring pathobiology from structural MRI in schizophrenia and bipolar disorder: Modeling head motion and neuroanatomical specificity.

    PubMed

    Yao, Nailin; Winkler, Anderson M; Barrett, Jennifer; Book, Gregory A; Beetham, Tamara; Horseman, Rachel; Leach, Olivia; Hodgson, Karen; Knowles, Emma E; Mathias, Samuel; Stevens, Michael C; Assaf, Michal; van Erp, Theo G M; Pearlson, Godfrey D; Glahn, David C

    2017-08-01

    Despite over 400 peer-reviewed structural MRI publications documenting neuroanatomic abnormalities in bipolar disorder and schizophrenia, the confounding effects of head motion and the regional specificity of these defects are unclear. Using a large cohort of individuals scanned on the same research dedicated MRI with broadly similar protocols, we observe reduced cortical thickness indices in both illnesses, though less pronounced in bipolar disorder. While schizophrenia (n = 226) was associated with wide-spread surface area reductions, bipolar disorder (n = 227) and healthy comparison subjects (n = 370) did not differ. We replicate earlier reports that head motion (estimated from time-series data) influences surface area and cortical thickness measurements and demonstrate that motion influences a portion, but not all, of the observed between-group structural differences. Although the effect sizes for these differences were small to medium, when global indices were covaried during vertex-level analyses, between-group effects became nonsignificant. This analysis raises doubts about the regional specificity of structural brain changes, possible in contrast to functional changes, in affective and psychotic illnesses as measured with current imaging technology. Given that both schizophrenia and bipolar disorder showed cortical thickness reductions, but only schizophrenia showed surface area changes, and assuming these measures are influenced by at least partially unique sets of biological factors, then our results could indicate some degree of specificity between bipolar disorder and schizophrenia. Hum Brain Mapp 38:3757-3770, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  3. Prevalences of autoimmune diseases in schizophrenia, bipolar I and II disorder, and controls.

    PubMed

    Cremaschi, Laura; Kardell, Mathias; Johansson, Viktoria; Isgren, Anniella; Sellgren, Carl M; Altamura, A Carlo; Hultman, Christina M; Landén, Mikael

    2017-12-01

    Previous studies on the relationship between autoimmune diseases, schizophrenia, and bipolar disorder are mainly based on hospital discharge registers with insufficient coverage of outpatient data. Furthermore, data is scant on the prevalence of autoimmune diseases in bipolar subgroups. Here we estimate the self-reported prevalences of autoimmune diseases in schizophrenia, bipolar disorder type I and II, and controls. Lifetime prevalence of autoimmune diseases was assessed through a structured interview in a sample of 9076 patients (schizophrenia N = 5278, bipolar disorder type I N = 1952, type II N = 1846) and 6485 controls. Comparative analyses were performed using logistic regressions. The prevalence of diabetes type 1 did not differ between groups. Hyperthyroidism, hypothyroidism regardless of lithium effects, rheumatoid arthritis, and polymyalgia rheumatica were most common in bipolar disorder. Systemic lupus erythematosus was less common in bipolar disorder than in the other groups. The rate of autoimmune diseases did not differ significantly between bipolar subgroups. We conclude that prevalences of autoimmune diseases show clear differences between schizophrenia and bipolar disorder, but not between the bipolar subgroups. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Bipolar nickel-hydrogen battery design

    NASA Technical Reports Server (NTRS)

    Koehler, C. W.; Applewhite, A. Z.; Kuo, Y.

    1985-01-01

    The initial design for the NASA-Lewis advanced nickel-hydrogen battery is discussed. Fabrication of two 10-cell boilerplate battery stacks will soon begin. The test batteries will undergo characterization testing and low Earth orbit life cycling. The design effectively deals with waste heat generated in the cell stack. Stack temperatures and temperature gradients are maintained to acceptable limits by utilizing the bipolar conduction plate as a heat path to the active cooling fluid panel external to the edge of the cell stack. The thermal design and mechanical design of the battery stack together maintain a materials balance within the cell. An electrolyte seal on each cell frame prohibits electrolyte bridging. An oxygen recombination site and electrolyte reservoir/separator design does not allow oxygen to leave the cell in which it was generated.

  5. Engineered Graphene Materials: Synthesis and Applications for Polymer Electrolyte Membrane Fuel Cells.

    PubMed

    He, Daping; Tang, Haolin; Kou, Zongkui; Pan, Mu; Sun, Xueliang; Zhang, Jiujun; Mu, Shichun

    2017-05-01

    Engineered graphene materials (EGMs) with unique structures and properties have been incorporated into various components of polymer electrolyte membrane fuel cells (PEMFCs) such as electrode, membrane, and bipolar plates to achieve enhanced performances in terms of electrical conductivity, mechanical durability, corrosion resistance, and electrochemical surface area. This research news article provides an overview of the recent development in EGMs and EGM-based PEMFCs with a focus on the effects of EGMs on PEMFC performance when they are incorporated into different components of PEMFCs. The challenges of EGMs for practical PEMFC applications in terms of production scale, stability, conductivity, and coupling capability with other materials are also discussed and the corresponding measures and future research trends to overcome such challenges are proposed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Ionomer equivalent weight structuring in the cathode catalyst layer of automotive fuel cells: Effect on performance, current density distribution and electrochemical impedance spectra

    NASA Astrophysics Data System (ADS)

    Herden, Susanne; Hirschfeld, Julian A.; Lohri, Cyrill; Perchthaler, Markus; Haase, Stefan

    2017-10-01

    To improve the performance of proton exchange membrane fuel cells, membrane electrode assemblies (MEAs) with segmented cathode electrodes have been manufactured. Electrodes with a higher and lower ionomer equivalent weight (EW) were used and analyzed using current density and temperature distribution, polarization curve, temperature sweep and electrochemical impedance spectroscopy measurements. These were performed using automotive metallic bipolar plates and operating conditions. Measurement data were used to manufacture an optimized segmented cathode electrode. We were able to show that our results are transferable from a small scale hardware to automotive application and that an ionomer EW segmentation of the cathode leads to performance improvement in a broad spectrum of operating conditions. Furthermore, we confirmed our results by using in-situ electrochemical impedance spectroscopy.

  7. NASA Tech Briefs, April 2009

    NASA Technical Reports Server (NTRS)

    2009-01-01

    Topics covered include: Direct-Solve Image-Based Wavefront Sensing; Use of UV Sources for Detection and Identification of Explosives; Using Fluorescent Viruses for Detecting Bacteria in Water; Gradiometer Using Middle Loops as Sensing Elements in a Low-Field SQUID MRI System; Volcano Monitor: Autonomous Triggering of In-Situ Sensors; Wireless Fluid-Level Sensors for Harsh Environments; Interference-Detection Module in a Digital Radar Receiver; Modal Vibration Analysis of Large Castings; Structural/Radiation-Shielding Epoxies; Integrated Multilayer Insulation; Apparatus for Screening Multiple Oxygen-Reduction Catalysts; Determining Aliasing in Isolated Signal Conditioning Modules; Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems; Spectrum Analyzers Incorporating Tunable WGM Resonators; Quantum-Well Thermophotovoltaic Cells; Bounded-Angle Iterative Decoding of LDPC Codes; Conversion from Tree to Graph Representation of Requirements; Parallel Hybrid Vehicle Optimal Storage System; and Anaerobic Digestion in a Flooded Densified Leachbed.

  8. Interaction between BDNF rs6265 Met allele and low family cohesion is associated with smaller left hippocampal volume in pediatric bipolar disorder.

    PubMed

    Zeni, Cristian Patrick; Mwangi, Benson; Cao, Bo; Hasan, Khader M; Walss-Bass, Consuelo; Zunta-Soares, Giovana; Soares, Jair C

    2016-01-01

    Genetic and environmental factors are implicated in the onset and evolution of pediatric bipolar disorder, and may be associated to structural brain abnormalities. The aim of our study was to assess the impact of the interaction between the Brain-Derived Neurotrophic Factor (BDNF) rs6265 polymorphism and family functioning on hippocampal volumes of children and adolescents with bipolar disorder, and typically-developing controls. We evaluated the family functioning cohesion subscale using the Family Environment Scale-Revised, genotyped the BDNF rs6265 polymorphism, and performed structural brain imaging in 29 children and adolescents with bipolar disorder, and 22 healthy controls. We did not find significant differences between patients with BD or controls in left or right hippocampus volume (p=0.44, and p=0.71, respectively). However, we detected a significant interaction between low scores on the cohesion subscale and the presence of the Met allele at BNDF on left hippocampal volume of patients with bipolar disorder (F=3.4, p=0.043). None of the factors independently (BDNF Val66Met, cohesion scores) was significantly associated with hippocampal volume differences. small sample size, cross-sectional study. These results may lead to a better understanding of the impact of the interaction between genes and environment factors on brain structures associated to bipolar disorder and its manifestations. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Multimodal Neuroimaging of Frontolimbic Structure and Function Associated With Suicide Attempts in Adolescents and Young Adults With Bipolar Disorder.

    PubMed

    Johnston, Jennifer A Y; Wang, Fei; Liu, Jie; Blond, Benjamin N; Wallace, Amanda; Liu, Jiacheng; Spencer, Linda; Cox Lippard, Elizabeth T; Purves, Kirstin L; Landeros-Weisenberger, Angeli; Hermes, Eric; Pittman, Brian; Zhang, Sheng; King, Robert; Martin, Andrés; Oquendo, Maria A; Blumberg, Hilary P

    2017-07-01

    Bipolar disorder is associated with high risk for suicidal behavior that often develops in adolescence and young adulthood. Elucidation of involved neural systems is critical for prevention. This study of adolescents and young adults with bipolar disorder with and without a history of suicide attempts combines structural, diffusion tensor, and functional MR imaging methods to investigate implicated abnormalities in the morphology and structural and functional connectivity within frontolimbic systems. The study had 26 participants with bipolar disorder who had a prior suicide attempt (the attempter group) and 42 participants with bipolar disorder without a suicide attempt (the nonattempter group). Regional gray matter volume, white matter integrity, and functional connectivity during processing of emotional stimuli were compared between groups, and differences were explored for relationships between imaging modalities and associations with suicide-related symptoms and behaviors. Compared with the nonattempter group, the attempter group showed significant reductions in gray matter volume in the orbitofrontal cortex, hippocampus, and cerebellum; white matter integrity in the uncinate fasciculus, ventral frontal, and right cerebellum regions; and amygdala functional connectivity to the left ventral and right rostral prefrontal cortex. In exploratory analyses, among attempters, there was a significant negative correlation between right rostral prefrontal connectivity and suicidal ideation and between left ventral prefrontal connectivity and attempt lethality. Adolescent and young adult suicide attempters with bipolar disorder demonstrate less gray matter volume and decreased structural and functional connectivity in a ventral frontolimbic neural system subserving emotion regulation. Among attempters, reductions in amygdala-prefrontal functional connectivity may be associated with severity of suicidal ideation and attempt lethality.

  10. Cortical complexity in bipolar disorder applying a spherical harmonics approach.

    PubMed

    Nenadic, Igor; Yotter, Rachel A; Dietzek, Maren; Langbein, Kerstin; Sauer, Heinrich; Gaser, Christian

    2017-05-30

    Recent studies using surface-based morphometry of structural magnetic resonance imaging data have suggested that some changes in bipolar disorder (BP) might be neurodevelopmental in origin. We applied a novel analysis of cortical complexity based on fractal dimensions in high-resolution structural MRI scans of 18 bipolar disorder patients and 26 healthy controls. Our region-of-interest based analysis revealed increases in fractal dimensions (in patients relative to controls) in left lateral orbitofrontal cortex and right precuneus, and decreases in right caudal middle frontal, entorhinal cortex, and right pars orbitalis, and left fusiform and posterior cingulate cortices. While our analysis is preliminary, it suggests that early neurodevelopmental pathologies might contribute to bipolar disorder, possibly through genetic mechanisms. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  11. Bipolar resistive switching in room temperature grown disordered vanadium oxide thin-film devices

    NASA Astrophysics Data System (ADS)

    Wong, Franklin J.; Sriram, Tirunelveli S.; Smith, Brian R.; Ramanathan, Shriram

    2013-09-01

    We demonstrate bipolar switching with high OFF/ON resistance ratios (>104) in Pt/vanadium oxide/Cu structures deposited entirely at room temperature. The SET (RESET) process occurs when negative (positive) bias is applied to the top Cu electrode. The vanadium oxide (VOx) films are amorphous and close to the vanadium pentoxide stoichiometry. We also investigated Cu/VOx/W structures, reversing the position of the Cu electrode, and found the same polarity dependence with respect to the top and bottom electrodes, which suggests that the bipolar nature is linked to the VOx layer itself. Bipolar switching can be observed at 100 °C, indicating that it not due to a temperature-induced metal-insulator transition of a vanadium dioxide second phase. We discuss how ionic drift can lead to the bipolar electrical behavior of our junctions, similar to those observed in devices based on several other defective oxides. Such low-temperature processed oxide switches could be of relevance to back-end or package integration processing schemes.

  12. Cross-national prevalence and cultural correlates of bipolar I disorder.

    PubMed

    Johnson, Kaja R; Johnson, Sheri L

    2014-07-01

    Bipolar disorder has been consistently related to heightened sensitivity to reward. Greater reward sensitivity predicts the onset of disorder, a more severe course, and conversion from milder to severe forms. No studies consider whether cultural factors related to reward sensitivity influence the course of bipolar disorder. This study examines the relationship of reward-relevant cultural values to global prevalence rates of bipolar I disorder. Lifetime prevalence of bipolar I disorder for 17 countries was drawn from epidemiological studies that used structured diagnostic interviews of large community samples. Bivariate correlations were used to assess the relationship of bipolar disorder prevalence with national scores on four reward-relevant cultural dimensions (Power Distance, Individualism, Long-Term Orientation, and Performance Orientation). The prevalence of bipolar I disorder was correlated in the predicted manner with Power Distance and Individualism, and with Long-Term Orientation and Performance Orientation after outliers were removed. Findings provide evidence for a cultural model of reward sensitivity in bipolar disorder.

  13. New insights into the endophenotypic status of cognition in bipolar disorder: genetic modelling study of twins and siblings.

    PubMed

    Georgiades, Anna; Rijsdijk, Fruhling; Kane, Fergus; Rebollo-Mesa, Irene; Kalidindi, Sridevi; Schulze, Katja K; Stahl, Daniel; Walshe, Muriel; Sahakian, Barbara J; McDonald, Colm; Hall, Mei-Hua; Murray, Robin M; Kravariti, Eugenia

    2016-06-01

    Twin studies have lacked statistical power to apply advanced genetic modelling techniques to the search for cognitive endophenotypes for bipolar disorder. To quantify the shared genetic variability between bipolar disorder and cognitive measures. Structural equation modelling was performed on cognitive data collected from 331 twins/siblings of varying genetic relatedness, disease status and concordance for bipolar disorder. Using a parsimonious AE model, verbal episodic and spatial working memory showed statistically significant genetic correlations with bipolar disorder (rg = |0.23|-|0.27|), which lost statistical significance after covarying for affective symptoms. Using an ACE model, IQ and visual-spatial learning showed statistically significant genetic correlations with bipolar disorder (rg = |0.51|-|1.00|), which remained significant after covarying for affective symptoms. Verbal episodic and spatial working memory capture a modest fraction of the bipolar diathesis. IQ and visual-spatial learning may tap into genetic substrates of non-affective symptomatology in bipolar disorder. © The Royal College of Psychiatrists 2016.

  14. Reduced Amygdalar Gray Matter Volume in Familial Pediatric Bipolar Disorder

    ERIC Educational Resources Information Center

    Chang, Kiki; Karchemskiy, Asya; Barnea-Goraly, Naama; Garrett, Amy; Simeonova, Diana Iorgova; Reiss, Allan

    2005-01-01

    Objective: Subcortical limbic structures have been proposed to be involved in the pathophysiology of adult and pediatric bipolar disorder (BD). We sought to study morphometric characteristics of these structures in pediatric subjects with familial BD compared with healthy controls. Method: Twenty children and adolescents with BD I (mean age = 14.6…

  15. Performance evaluation of a bipolar electrolysis/electrocoagulation (EL/EC) reactor to enhance the sludge dewaterability.

    PubMed

    Gharibi, Hamed; Sowlat, Mohammad Hossein; Mahvi, Amir Hossein; Keshavarz, Morteza; Safari, Mohammad Hossein; Lotfi, Saeedeh; Bahram Abadi, Mahnaz; Alijanzadeh, Azim

    2013-01-01

    The present study aimed to evaluate the performance of a bipolar electrolysis/electrocoagulation reactor designed to enhance the sludge dewaterability. The reactor was 15 L in volume, with two series of plates used in it; Ti/RuO(2) plates for the electrolysis of the sludge, and also aluminum and iron plates for electrocoagulation process. The dewaterability of the sludge was determined in terms of its capillary suction time (CST) and specific resistance to filtration (SRF), while the degree of sludge disintegration was determined based on the value of degree of sludge disintegration (DD(SCOD)). The maximum reduction in CST and SRF was observed at a detention time of 20 min and a voltage of 30 V. However, increasing of both detention time and voltage significantly increased the values of CST and SRF even to an extent that they both exceeded those of the untreated sludge. The optimal degree of sludge disintegration achieved by the present study was 2.5%, which was also achieved at a detention time of 20 min and a voltage of 30V. As reported previously, increased DD(SCOD) values led to increasing CST and SRF values, due primarily to the disruption of the sludge flocs. According to the results from the present study, it can be concluded that simultaneous application of electrocoagulation and electrolysis is effective in enhancing the sludge dewaterability, because electrocoagulation helps to achieve a higher degree of sludge disintegration while maintaining the desired sludge dewaterability. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Interactions between bipolar disorder and antisocial personality disorder in trait impulsivity and severity of illness.

    PubMed

    Swann, A C; Lijffijt, M; Lane, S D; Steinberg, J L; Moeller, F G

    2010-06-01

    We investigated trait impulsivity in bipolar disorder and antisocial personality disorder (ASPD) with respect to severity and course of illness. Subjects included 78 controls, 34 ASPD, 61 bipolar disorder without Axis II disorder, and 24 bipolar disorder with ASPD, by Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (SCID-I and -II). Data were analyzed using general linear model and probit analysis. Barratt Impulsiveness Scale (BIS-11) scores were higher in ASPD (effect sizes 0.5-0.8) or bipolar disorder (effect size 1.45) than in controls. Subjects with both had more suicide attempts and previous episodes than bipolar disorder alone, and more substance-use disorders and suicide attempts than ASPD alone. BIS-11 scores were not related to severity of crimes. Impulsivity was higher in bipolar disorder with or without ASPD than in ASPD alone, and higher in ASPD than in controls. Adverse effects of bipolar disorder in ASPD, but not of ASPD in bipolar disorder, were accounted for by increased impulsivity.

  17. Relation between Amygdala Structure and Function in Adolescents with Bipolar Disorder

    ERIC Educational Resources Information Center

    Kalmar, Jessica H.; Wang, Fei; Chepenik, Lara G.; Womer, Fay Y.; Jones, Monique M.; Pittman, Brian; Shah, Maulik P.; Martin, Andres; Constable, R. Todd; Blumberg, Hilary P.

    2009-01-01

    Adolescents with bipolar disorder showed decreased amygdala volume and increased amygdala response to emotional faces. Amygdala volume is inversely related to activation during emotional face processing.

  18. A 10-Year Prospective Study of Prodromal Patterns for Bipolar Disorder among Amish Youth

    ERIC Educational Resources Information Center

    Shaw, Jon A.; Egeland, Janice A.; Endicott, Jean; Allen, Cleona R.; Hostetter, Abram M.

    2005-01-01

    Objective: Prospective study of well children at risk of bipolarity to identify the frequency and pattern of potentially prodromal symptoms/behaviors for bipolar disorder type I (BPI) disorder. Method: A total of 110 at-risk children with a BPI parent and 112 children with well parents were studied. Ten-year data collection used structured and…

  19. Corrosion resistant PEM fuel cell

    DOEpatents

    Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen Joel; Doll, Gary Lynn

    2001-07-17

    The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.

  20. Corrosion resistant PEM fuel cell

    DOEpatents

    Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen Joel; Doll, Gary Lynn

    2002-01-01

    The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.

  1. Corrosion resistant PEM fuel cell

    DOEpatents

    Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen J.; Doll, Gary L.

    1997-01-01

    The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.

  2. Protective coatings on stainless steel bipolar plates for proton exchange membrane (PEM) electrolysers

    NASA Astrophysics Data System (ADS)

    Gago, A. S.; Ansar, S. A.; Saruhan, B.; Schulz, U.; Lettenmeier, P.; Cañas, N. A.; Gazdzicki, P.; Morawietz, T.; Hiesgen, R.; Arnold, J.; Friedrich, K. A.

    2016-03-01

    Proton exchange membrane (PEM) electrolysis is a promising technology for large H2 production from surplus electricity from renewable sources. However, the electrolyser stack is costly due to the manufacture of bipolar plates (BPP). Stainless steel can be used as an alternative, but it must be coated. Herein, dense titanium coatings are produced on stainless steel substrates by vacuum plasma spraying (VPS). Further surface modification of the Ti coating with Pt (8 wt% Pt/Ti) deposited by physical vapour deposition (PVD) magnetron sputtering reduces the interfacial contact resistance (ICR). The Ti and Pt/Ti coatings are characterised by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and X-ray photoelectron microscopy (XPS). Subsequently, the coatings are evaluated in simulated and real PEM electrolyser environments, and they managed to fully protect the stainless steel substrate. In contrast, the absence of the thermally sprayed Ti layer between Pt and stainless steel leads to pitting corrosion. The Pt/Ti coating is tested in a PEM electrolyser cell for almost 200 h, exhibiting an average degradation rate of 26.5 μV h-1. The results reported here demonstrate the possibility of using stainless steel as a base material for the stack of a PEM electrolyser.

  3. Quasi-bipolar battery construction and method of fabricating

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E. (Inventor); Edwards, Dean B. (Inventor)

    1982-01-01

    A lightweight, battery construction for lead acid batteries in which biplates are formed from a continuous strip of thermoplastic material, one face of the strip being provided with a plurality of electrically isolated lead strip arrays, each having a transverse axis about which the strip is folded or pleated to provide pleated biplate walls. The pleated continuous strip is sealed along edge longitudinal portions to provide chambers for receiving a plurality of non-conductive thermoplastic separator-plates and to contain electrolyte liquid. Separator-plates support resilient yieldable porous glass mats and scrim fabric in which active material is carried. The assembly of pleated biplates and separator-plates is maintained in pressure relation by exterior resilient means. A method of making such a continuous pleated biplate construction and of assembling one or more battery modules which may be connected in series or in parallel. A biplate construction having continuously wound lead stripes attached to a substrate.

  4. Qualitative and semiquantitative Fourier transformation using a noncoherent system.

    PubMed

    Rogers, G L

    1979-09-15

    A number of authors have pointed out that a system of zone plates combined with a diffuse source, transparent input, lens, and focusing screen will display on the output screen the Fourier transform of the input. Strictly speaking, the transform normally displayed is the cosine transform, and the bipolar output is superimposed on a dc gray level to give a positive-only intensity variation. By phase-shifting one zone plate the sine transform is obtained. Temporal modulation is possible. It is also possible to redesign the system to accept a diffusely reflecting input at the cost of introducing a phase gradient in the output. Results are given of the sine and cosine transforms of a small circular aperture. As expected, the sine transform is a uniform gray. Both transforms show unwanted artifacts beyond 0.1 rad off-axis. An analysis shows this is due to unwanted circularly symmetrical moire patterns between the zone plates.

  5. Piezoelectric and dielectric performance of poled lead zirconate titanate subjected to electric cyclic fatigue

    NASA Astrophysics Data System (ADS)

    Wang, Hong; Matsunaga, Tadashi; Lin, Hua-Tay; Mottern, Alexander M.

    2012-02-01

    Poled lead zirconate titanate (PZT) material as a single-layer plate was tested using a piezodilatometer under electric cyclic loading in both unipolar and bipolar modes. Its responses were evaluated using unipolar and bipolar measurements on the same setup. The mechanical strain and charge density loops exhibited various variations when the material was cycled for more than 108 cycles. The various quantities including loop amplitude, hysteresis, switchable polarization, and coercive field were characterized accordingly under the corresponding measurement conditions. At the same time, the offset polarization and bias electric field of the material were observed to be changed and the trend was found to be related to the measurement conditions also. Finally, the piezoelectric and dielectric coefficients were analyzed and their implications for the application of interest have been discussed.

  6. Bipolar lead-acid batteries for electrical actuation applications

    NASA Technical Reports Server (NTRS)

    Pierce, Douglas C.; Gentry, William O.; Hall, David

    1994-01-01

    This document presents in viewgraph format information on bipolar battery development at Johnson Controls, Incorporated. The organization structure, goals, progress to date, future plans, and battery parameters and electrical properties are given.

  7. Cross-Sectional and Longitudinal Abnormalities in Brain Structure in Children with Severe Mood Dysregulation or Bipolar Disorder

    ERIC Educational Resources Information Center

    Adleman, Nancy E.; Fromm, Stephen J.; Razdan, Varun; Kayser, Reilly; Dickstein, Daniel P.; Brotman, Melissa A.; Pine, Daniel S.; Leibenluft, Ellen

    2012-01-01

    Background: There is debate as to whether chronic irritability (operationalized as severe mood dysregulation, SMD) is a developmental form of bipolar disorder (BD). Although structural brain abnormalities in BD have been demonstrated, no study compares neuroanatomy among SMD, BD, and healthy volunteers (HV) either cross-sectionally or over time.…

  8. Bipolar battery

    DOEpatents

    Kaun, Thomas D.

    1992-01-01

    A bipolar battery having a plurality of cells. The bipolar battery includes: a negative electrode; a positive electrode and a separator element disposed between the negative electrode and the positive electrode, the separator element electrically insulating the electrodes from one another; an electrolyte disposed within at least one of the negative electrode, the positive electrode and the separator element; and an electrode containment structure including a cup-like electrode holder.

  9. Parenting practices in middle childhood mediate the relation between growing up with a parent having bipolar disorder and offspring psychopathology from childhood into early adulthood.

    PubMed

    Iacono, Vanessa; Beaulieu, Leah; Hodgins, Sheilagh; Ellenbogen, Mark A

    2018-05-01

    The offspring of parents with bipolar disorder (OBD) are at high risk for developing mental disorders. In addition to genetic factors, environmental risk is purported to be associated with these negative outcomes. However, few studies have examined this relation. Using concurrent and longitudinal data, we examined if support, structure, and control provided by parents in middle childhood mediated the relation between having a parent with or without bipolar disorder, and offspring mental health. The sample included 145 offspring (77 OBD, 68 controls) aged 4 to 14 years and their parents. Parent and teacher ratings of child behavior were collected, and diagnostic assessments were conducted in offspring 12 years later (n = 101). Bootstrapping analyses showed that low levels of structure mediated the relation between having a parent with bipolar disorder and elevated internalizing and externalizing difficulties during middle childhood. For the longitudinal outcomes, parental control emerged as the strongest mediator of the relation between parents' bipolar disorder and offspring psychopathology. Suboptimal childrearing may have different immediate and enduring consequences on mental health outcomes in the OBD. Parental structure has robust effects on emotional and behavioral problems in middle childhood, while levels of control promote psychological adjustment in the OBD as they mature.

  10. Review of Heterojunctin Bipolar Transistor Structure, Applications, and Reliability

    NASA Technical Reports Server (NTRS)

    Lee, C.; Kayali, S.

    1993-01-01

    Heterojunction Bipolar Transistors (HBTs) are increasingly employed in high frequency, high linerity, and high efficiency applications. As the utilization of these devices becomes more widespread, their operation will be viewed with more scrutiny.

  11. Dysfunctional Cognitions among Offspring of Individuals with Bipolar Disorder.

    PubMed

    Ruggero, Camilo J; Bain, Kathleen M; Smith, Patrick M; Kilmer, Jared N

    2015-07-01

    Individuals with bipolar disorder often endorse dysfunctional beliefs consistent with cognitive models of bipolar disorder (Beck, 1976; Mansell, 2007). The present study sought to assess whether young adult offspring of those with bipolar disorder would also endorse these beliefs, independent of their own mood episode history. Participants (N = 89) were young adult college students with a parent with bipolar disorder (n = 27), major depressive disorder (MDD; n = 30), or no mood disorder (n = 32). Semi-structured interviews of the offspring were used to assess diagnoses. Dysfunctional beliefs related to Beck and colleagues' (2006) and Mansell's (2007) cognitive models were assessed. Unlike offspring of parents with MDD or no mood disorder, those with a parent with bipolar disorder endorsed significantly more dysfunctional cognitions associated with extreme appraisal of mood states, even after controlling for their own mood diagnosis. Once affected by a bipolar or depressive disorder, offspring endorsed dysfunctional cognitions across measures. Dysfunctional cognitions, particularly those related to appraisals of mood states and their potential consequences, are evident in young adults with a parent who has bipolar disorder and may represent targets for psychotherapeutic intervention.

  12. Relationship between body mass index and hippocampal glutamate/glutamine in bipolar disorder.

    PubMed

    Bond, David J; da Silveira, Leonardo Evangelista; MacMillan, Erin L; Torres, Ivan J; Lang, Donna J; Su, Wayne; Honer, William G; Lam, Raymond W; Yatham, Lakshmi N

    2016-02-01

    We previously reported that patients with early-stage bipolar disorder, but not healthy comparison controls, had body mass index (BMI)-related volume reductions in limbic brain areas, suggesting that the structural brain changes characteristic of bipolar disorder were more pronounced with increased weight. To determine whether the most consistently reported neurochemical abnormality in bipolar disorder, increased glutamate/glutamine (Glx), was also more prominent with higher BMI. We used single-voxel proton magnetic resonance spectroscopy to measure hippocampal Glx in 51 patients with first-episode mania (mean BMI = 24.1) and 28 healthy controls (mean BMI = 23.3). In patients, but not healthy controls, linear regression demonstrated that higher BMI predicted greater Glx. Factorial ANCOVA showed a significant BMI × diagnosis interaction, confirming a distinct effect of weight on Glx in patients. Together with our volumetric studies, these results suggest that higher BMI is associated with more pronounced structural and neurochemical limbic brain changes in bipolar disorder, even in early-stage patients with low obesity rates. © The Royal College of Psychiatrists 2016.

  13. Corrosion resistant PEM fuel cell

    DOEpatents

    Li, Y.; Meng, W.J.; Swathirajan, S.; Harris, S.J.; Doll, G.L.

    1997-04-29

    The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell`s operating environment. Stainless steels rich in Cr, Ni, and Mo are particularly effective protective interlayers. 6 figs.

  14. Three Dimensional Forming Simulation of the Shielded Slot Plate for the MCFC Using a Ductile Fracture Criterion

    NASA Astrophysics Data System (ADS)

    Lee, C. H.; Yang, D. Y.; Lee, S. R.; Chang, I. G.; Lee, T. W.

    2011-08-01

    The shielded slot plate, which has a sheared corrugated trapezoidal pattern, is a component of the metallic bipolar plate for the molten carbonate fuel cell (MCFC). In order to increase the efficiency of the fuel cell, the unit cell of the shielded slot plate should have a relatively large upper area. Additionally, defects from the forming process should be minimized. In order to simulate the slitting process, whereby sheared corrugated patterns are formed, ductile fracture criteria based on the histories of stress and strain are employed. The user material subroutine VUMAT is employed for implementation of the material and ductile fracture criteria in the commercial FEM software ABAQUS. The variables of the ductile fracture criteria were determined by comparing the simulation results and the experimental results of the tension test and the shearing test. Parametric studies were conducted to determine the critical value of the ductile fracture criterion. Employing these ductile fracture criteria, the three dimensional forming process of the shielded slot plate was numerically simulated. The effects of the slitting process in the forming process of the shielded slot plate were analyzed through a FEM simulation and experimental studies. Finally, experiments involving microscopic and macroscopic observations were conducted to verify the numerical simulations of the 3-step forming process.

  15. Investigations on the micro-scale surface interactions at the tool and workpiece interface in micro-manufacturing of bipolar plates for proton exchange membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Peker, Mevlut Fatih

    Micro-forming studies have been more attractive in recent years because of miniaturization trend. One of the promising metal forming processes, micro-stamping, provides durability, strength, surface finish, and low cost for metal products. Hence, it is considered a prominent method for fabricating bipolar plates (BPP) with micro-channel arrays on large metallic surfaces to be used in Proton Exchange Membrane Fuel Cells (PEMFC). Major concerns in micro-stamping of high volume BPPs are surface interactions between micro-stamping dies and blank metal plates, and tribological changes. These concerns play a critical role in determining the surface quality, channel formation, and dimensional precision of bipolar plates. The surface quality of BPP is highly dependent on the micro-stamping die surface, and process conditions due to large ratios of surface area to volume (size effect) that cause an increased level of friction and wear issues at the contact interface. Due to the high volume and fast production rates, BPP surface characteristics such as surface roughness, hardness, and stiffness may change because of repeated interactions between tool (micro-forming die) and workpiece (sheet blank of interest). Since the surface characteristics of BPPs have a strong effect on corrosion and contact resistance of bipolar plates, and consequently overall fuel cell performance, evolution of surface characteristics at the tool and workpiece should be monitored, controlled, and kept in acceptable ranges throughout the long production cycles to maintain the surface quality. Compared to macro-forming operations, tribological changes in micro-forming process are bigger challenges due to their dominance and criticality. Therefore, tribological size effect should be considered for better understanding of tribological changes in micro-scale. The integrity of process simulation to the experiments, on the other hand, is essential. This study describes an approach that aims to investigate the surface topography changes during long-run micro-stamping of BPPs, and establish relationships between surface roughness--corrosion resistance and surface roughness-contact resistance characteristics of BPPs. Formability levels of formed BPPs and repeatability characteristics of the process were investigated. In addition, blank thickness changes, von-Mises stress, plastic strain levels and distributions of micro-stamping process were determined via finite element analysis (FEA). Test results revealed that the surface roughness change for the stamping dies and BPPs was unsteady (no trend) due to the continuous change of surface topography (i.e. asperity deformation). Sub-micron range local plastic deformations on stamping dies led to surface topography changes on BPP in long-run manufacturing case. As surface defects trigger corrosion, the correlation between surface roughness and corrosion resistance of BPPs was found to be direct. Increasing number of surface irregularities (asperities) lowered contact surface area that resulted in increased contact resistance. ZrN coated BPPs, on the other hand, did not change surface roughness, however; it improved the protection of BPPs against corrosion significantly. In addition, ZrN coating increased the conductivity of BPPs and reduced the contact resistance between BPP and gas diffusion layer (GDL), at certain extent. As dimensional stability and repeatability was confirmed in forming of both uncoated and coated BPPs during the long run manufacturing, different formability levels were achieved for coated and uncoated samples. Lower channel height values were obtained for coated plates because of the different surface hardness of uncoated and coated plates. In tribological size effect part of study, micro stamping experiments using three different dies with distinct channel height values at different stamping force levels were performed. It was concluded that decrease in forming die dimensions led to increase in coefficient of friction as previously reported by other researchers as one of the consequences of tribological size effect. On the other hand, coefficient of friction values were not affected by the force levels used in the experiments and simulations, whereas plastic strain, equivalent stress, and formability levels were increased with increasing stamping force, as expected. In essence, this study proposed a methodology to investigate the long-run manufacturing effects on dimensional stability and surface characteristics of micro-stamped sheets. It also correlates these parameters to fuel cell performance measures such as interfacial contact and corrosion resistance.

  16. Develop and test fuel cell powered on-site integrated total energy systems: Phase 3, full-scale power plant development

    NASA Technical Reports Server (NTRS)

    Kaufman, A.; Pudick, S.; Wang, C. L.; Werth, J.; Whelan, J. A.

    1985-01-01

    Two 25 cell stacks of the 13 inch x 23 inch cell size (about 4kW) remain on test after 4000 hours and 2900 hours, respectively, using simulated reformate fuel. These tests are focusing on the durability of fuel cell stack components developed through the end of 1983. Also, these stacks are serving as forerunners of a 25kW stack that will contain 175 cells of the same size and will employ the same technology base. The stack technology development program has focused on a new, low cost bipolar plate edge seal technique and evaluation of advanced cathode catalysts, an electrolyte replenishment system, and nonmetallic cooling plates in small stacks.

  17. Bipolar resistive switching in graphene oxide based metal insulator metal structure for non-volatile memory applications

    NASA Astrophysics Data System (ADS)

    Singh, Rakesh; Kumar, Ravi; Kumar, Anil; Kashyap, Rajesh; Kumar, Mukesh; Kumar, Dinesh

    2018-05-01

    Graphene oxide based devices have attracted much attention recently because of their possible application in next generation electronic devices. In this study, bipolar resistive switching characteristics of graphene oxide based metal insulator metal structure were investigated for nonvolatile memories. The graphene oxide was prepared by the conventional Hummer's method and deposited on ITO coated glass by spin-coating technique. The dominant mechanism of resistive switching is the formation and rupture of the conductive filament inside the graphene oxide. The conduction mechanism for low and high resistance states are dominated by two mechanism the ohmic conduction and space charge limited current (SCLC) mechanism, respectively. Atomic Force Microscopy, X-ray diffraction, Cyclic-Voltammetry were conducted to observe the morphology, structure and behavior of the material. The fabricated device with Al/GO/ITO structure exhibited reliable bipolar resistive switching with set & reset voltage of -2.3 V and 3V respectively.

  18. Dermatoglyphics in relation to brain volumes in twins concordant and discordant for bipolar disorder.

    PubMed

    Vonk, R; van der Schot, A C; van Baal, G C M; van Oel, C J; Nolen, W A; Kahn, R S

    2014-12-01

    Palmar and finger dermatoglyphics are formed between the 10th and the 17th weeks of gestation and their morphology can be influenced by genetic or environmental factors, interfering with normal intrauterine development. As both the skin and the brain develop from the same embryonal ectoderm, dermatoglyphic alterations may be informative for early abnormal neurodevelopmental processes in the brain. We investigated whether dermatoglyphic alterations are related to structural brain abnormalities in bipolar disorder and to what extent they are of a genetic and of an environmental origin. Dermatoglyphics and volumetric data from structural MRI were obtained in 53 twin pairs concordant or discordant for bipolar disorder and 51 healthy matched control twin pairs. Structural equation modeling was used. Bipolar disorder was significantly positively associated with palmar a-b ridge count (ABRC), indicating higher ABRC in bipolar patients (rph=.17 (CI .04-.30)). Common genes appear to be involved because the genetic correlation with ABRC was significant (rph-A=.21 (CI .05-.36). Irrespective of disease, ABRC showed a genetically mediated association with brain volume, indicated by a significant genetic correlation rph-A of respectively -.36 (CI -.52 to -.22) for total brain, -.34 (CI -.51 to -.16) total cortical volume, -.27 (CI -.43 to -.08) cortical gray matter and -.23 (CI -.41 to -.04) cortical white matter. In conclusion, a genetically determined abnormal development of the foetal ectoderm between the 10th and 15th week of gestation appears related to smaller brain volumes in (subjects at risk for) bipolar disorder. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

  19. High Temperature Thermal Stability and Oxidation Resistance of Magnetron-sputtered Homogeneous CrAlON Coatings on 430 Steel

    NASA Astrophysics Data System (ADS)

    Kayani, A.; Wickey, K. J.; Nandasiri, M. I.; Moore, A.; Garratt, E.; AlFaify, S.; Gao, X.; Smith, R. J.; Buchanan, T. L.; Priyantha, W.; Kopczyk, M.; Gannon, P. E.; Gorokhovsky, V. I.

    2009-03-01

    The requirements of low cost and high-temperature corrosion resistance for bipolar interconnect plates in solid oxide fuel cell stacks has directed attention to the use of metal plates with oxidation resistant coatings. We have investigated the performance of steel plates with homogenous coatings of CrAlON (oxynitrides). The coatings were deposited using RF magnetron sputtering, with Ar as a sputtering gas. Oxygen in these coatings was not intentionally added. Oxygen might have come through contaminated nitrogen gas bottle, leak in the chamber or from the partial pressure of water vapors. Nitrogen was added during the growth process to get oxynitride coating. The Cr/Al composition ratio in the coatings was varied in a combinatorial approach. The coatings were subsequently annealed in air for up to 25 hours at 800° C. The composition of the coated plates and the rate of oxidation were characterized using Rutherford backscattering (RBS) and nuclear reaction analysis (NRA). From our results, we conclude that Al rich coatings are more susceptible to oxidation than Cr rich coatings.

  20. Bipolar Electrode Sample Preparation Devices

    NASA Technical Reports Server (NTRS)

    Song, Hongjun (Inventor); Wang, Yi (Inventor); Pant, Kapil (Inventor)

    2017-01-01

    An analyte selection device can include: a body defining a fluid channel having a channel inlet and channel outlet; a bipolar electrode (BPE) between the inlet and outlet; one of an anode or cathode electrically coupled with the BPE on a channel inlet side of the BPE and the other of the anode or cathode electrically coupled with the BPE on a channel outlet side of the BPE; and an electronic system operably coupled with the anode and cathode so as to polarize the BPE. The fluid channel can have any shape or dimension. The channel inlet and channel outlet can be longitudinal or lateral with respect to the longitudinal axis of the channel. The BPE can be any metallic member, such as a flat plate on a wall or mesh as a barrier BPE. The anode and cathode can be located at a position that polarizes the BPE.

  1. Brain Structural Effects of Psychopharmacological Treatment in Bipolar Disorder

    PubMed Central

    McDonald, Colm

    2015-01-01

    Bipolar disorder is associated with subtle neuroanatomical deficits including lateral ventricular enlargement, grey matter deficits incorporating limbic system structures, and distributed white matter pathophysiology. Substantial heterogeneity has been identified by structural neuroimaging studies to date and differential psychotropic medication use is potentially a substantial contributor to this. This selective review of structural neuroimaging and diffusion tensor imaging studies considers evidence that lithium, mood stabilisers, antipsychotic medication and antidepressant medications are associated with neuroanatomical variation. Most studies are negative and suffer from methodological weaknesses in terms of directly assessing medication effects on neuroanatomy, since they commonly comprise posthoc assessments of medication associations with neuroimaging metrics in small heterogenous patient groups. However the studies which report positive findings tend to form a relatively consistent picture whereby lithium and antiepileptic mood stabiliser use is associated with increased regional grey matter volume, especially in limbic structures. These findings are further supported by the more methodologically robust studies which include large numbers of patients or repeated intra-individual scanning in longitudinal designs. Some similar findings of an apparently ameliorative effect of lithium on white matter microstructure are also emerging. There is less support for an effect of antipsychotic or antidepressant medication on brain structure in bipolar disorder, but these studies are further limited by methodological difficulties. In general the literature to date supports a normalising effect of lithium and mood stabilisers on brain structure in bipolar disorder, which is consistent with the neuroprotective characteristics of these medications identified by preclinical studies. PMID:26412064

  2. Brain Structural Effects of Psychopharmacological Treatment in Bipolar Disorder.

    PubMed

    McDonald, Colm

    2015-01-01

    Bipolar disorder is associated with subtle neuroanatomical deficits including lateral ventricular enlargement, grey matter deficits incorporating limbic system structures, and distributed white matter pathophysiology. Substantial heterogeneity has been identified by structural neuroimaging studies to date and differential psychotropic medication use is potentially a substantial contributor to this. This selective review of structural neuroimaging and diffusion tensor imaging studies considers evidence that lithium, mood stabilisers, antipsychotic medication and antidepressant medications are associated with neuroanatomical variation. Most studies are negative and suffer from methodological weaknesses in terms of directly assessing medication effects on neuroanatomy, since they commonly comprise posthoc assessments of medication associations with neuroimaging metrics in small heterogenous patient groups. However the studies which report positive findings tend to form a relatively consistent picture whereby lithium and antiepileptic mood stabiliser use is associated with increased regional grey matter volume, especially in limbic structures. These findings are further supported by the more methodologically robust studies which include large numbers of patients or repeated intra-individual scanning in longitudinal designs. Some similar findings of an apparently ameliorative effect of lithium on white matter microstructure are also emerging. There is less support for an effect of antipsychotic or antidepressant medication on brain structure in bipolar disorder, but these studies are further limited by methodological difficulties. In general the literature to date supports a normalising effect of lithium and mood stabilisers on brain structure in bipolar disorder, which is consistent with the neuroprotective characteristics of these medications identified by preclinical studies.

  3. A prospective study of diagnostic conversion of major depressive disorder to bipolar disorder in pregnancy and postpartum.

    PubMed

    Sharma, Verinder; Xie, Bin; Campbell, M Karen; Penava, Debbie; Hampson, Elizabeth; Mazmanian, Dwight; Pope, Carley J

    2014-02-01

    The aim of the present study was to determine the rate of, and risk factors for, a change in diagnosis from major depressive disorder to bipolar disorder, and from bipolar II disorder to bipolar I disorder in pregnancy and postpartum. Patients with a prior history of major depressive disorder or bipolar II disorder were recruited between 24 and 28 weeks' gestation and followed through to one year postpartum. Diagnostic interviews were conducted using the Structured Clinical Interview for DSM-IV at study intake and repeated using the Mini-International Psychiatric Interview at one, three, six, and 12 months after childbirth. Fisher's exact test was used to assess the association between various risk factors and diagnostic switch. A total of 146 participants completed the intake interview and at least one follow-up interview postpartum. Of these, 92 were diagnosed with major depressive disorder and 54 with bipolar II disorder at intake. Six women (6.52%) experienced a diagnostic change from major depressive disorder to bipolar II disorder during the first six months after childbirth. There were no cases of switching to bipolar I disorder, but in one participant the diagnosis changed from bipolar II disorder to bipolar I disorder during the three months after childbirth. Bipolar switch was associated with a family history of bipolar disorder. The postpartum period appears to be a time of high risk for a new onset of hypomania in women with major depressive disorder. Our rate of diagnostic switching to bipolar II disorder (6.52%) is at least 11- to 18-fold higher than the rates of switching in similar studies conducted in both men and women. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. Investigating brain community structure abnormalities in bipolar disorder using path length associated community estimation.

    PubMed

    Gadelkarim, Johnson J; Ajilore, Olusola; Schonfeld, Dan; Zhan, Liang; Thompson, Paul M; Feusner, Jamie D; Kumar, Anand; Altshuler, Lori L; Leow, Alex D

    2014-05-01

    In this article, we present path length associated community estimation (PLACE), a comprehensive framework for studying node-level community structure. Instead of the well-known Q modularity metric, PLACE utilizes a novel metric, Ψ(PL), which measures the difference between intercommunity versus intracommunity path lengths. We compared community structures in human healthy brain networks generated using these two metrics and argued that Ψ(PL) may have theoretical advantages. PLACE consists of the following: (1) extracting community structure using top-down hierarchical binary trees, where a branch at each bifurcation denotes a collection of nodes that form a community at that level, (2) constructing and assessing mean group community structure, and (3) detecting node-level changes in community between groups. We applied PLACE and investigated the structural brain networks obtained from a sample of 25 euthymic bipolar I subjects versus 25 gender- and age-matched healthy controls. Results showed community structural differences in posterior default mode network regions, with the bipolar group exhibiting left-right decoupling. Copyright © 2013 Wiley Periodicals, Inc.

  5. Suicide attempts and clinical features of bipolar patients.

    PubMed

    Berkol, Tonguç D; İslam, Serkan; Kırlı, Ebru; Pınarbaşı, Rasim; Özyıldırım, İlker

    2016-06-01

    To identify clinical predictors of suicide attempts in patients with bipolar disorder. This study included bipolar patients who were treated in the Psychiatry Department, Haseki Training and Research Hospital, Istanbul, Turkey, between 2013 and 2014; an informed consent was obtained from the participants. Two  hundred and eighteen bipolar patients were assessed by using the structured clinical interview for Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) Axis-I (SCID-I) in order to detect all possible psychiatric comorbid diagnoses. Clinical predictors of suicide attempts were examined in attempters and non-attempters. The study design was retrospective. The lifetime suicide attempt rate for the entire sample was 19.2%. Suicide attempters with bipolar disorder had more lifetime comorbidity of eating disorder. Female gender and family history of mood disorder were significant predictors for suicide attempts. There was no difference between groups in terms of bipolar disorder subtype, onset age of bipolar disorder, total number of episodes, first and predominant episode type, suicide history in first degree relatives, severity of episodes, and hospitalization and being psychotic. Our study revealed that female gender, family history of mood disorder, and eating disorder are more frequent in bipolar patients with at least one suicide attempt.

  6. Brain structure–function associations in multi-generational families genetically enriched for bipolar disorder

    PubMed Central

    Schür, Remmelt; Sjouwerman, Rachel; Service, Susan K.; Araya, Carmen; Araya, Xinia; Bejarano, Julio; Knowles, Emma; Gomez-Makhinson, Juliana; Lopez, Maria C.; Aldana, Ileana; Teshiba, Terri M.; Abaryan, Zvart; Al-Sharif, Noor B.; Navarro, Linda; Tishler, Todd A.; Altshuler, Lori; Bartzokis, George; Escobar, Javier I.; Glahn, David C.; Thompson, Paul M.; Lopez-Jaramillo, Carlos; Macaya, Gabriel; Molina, Julio; Reus, Victor I.; Sabatti, Chiara; Cantor, Rita M.; Freimer, Nelson B.; Bearden, Carrie E.

    2015-01-01

    Recent theories regarding the pathophysiology of bipolar disorder suggest contributions of both neurodevelopmental and neurodegenerative processes. While structural neuroimaging studies indicate disease-associated neuroanatomical alterations, the behavioural correlates of these alterations have not been well characterized. Here, we investigated multi-generational families genetically enriched for bipolar disorder to: (i) characterize neurobehavioural correlates of neuroanatomical measures implicated in the pathophysiology of bipolar disorder; (ii) identify brain–behaviour associations that differ between diagnostic groups; (iii) identify neurocognitive traits that show evidence of accelerated ageing specifically in subjects with bipolar disorder; and (iv) identify brain–behaviour correlations that differ across the age span. Structural neuroimages and multi-dimensional assessments of temperament and neurocognition were acquired from 527 (153 bipolar disorder and 374 non-bipolar disorder) adults aged 18–87 years in 26 families with heavy genetic loading for bipolar disorder. We used linear regression models to identify significant brain–behaviour associations and test whether brain–behaviour relationships differed: (i) between diagnostic groups; and (ii) as a function of age. We found that total cortical and ventricular volume had the greatest number of significant behavioural associations, and included correlations with measures from multiple cognitive domains, particularly declarative and working memory and executive function. Cortical thickness measures, in contrast, showed more specific associations with declarative memory, letter fluency and processing speed tasks. While the majority of brain–behaviour relationships were similar across diagnostic groups, increased cortical thickness in ventrolateral prefrontal and parietal cortical regions was associated with better declarative memory only in bipolar disorder subjects, and not in non-bipolar disorder family members. Additionally, while age had a relatively strong impact on all neurocognitive traits, the effects of age on cognition did not differ between diagnostic groups. Most brain–behaviour associations were also similar across the age range, with the exception of cortical and ventricular volume and lingual gyrus thickness, which showed weak correlations with verbal fluency and inhibitory control at younger ages that increased in magnitude in older subjects, regardless of diagnosis. Findings indicate that neuroanatomical traits potentially impacted by bipolar disorder are significantly associated with multiple neurobehavioural domains. Structure–function relationships are generally preserved across diagnostic groups, with the notable exception of ventrolateral prefrontal and parietal association cortex, volumetric increases in which may be associated with cognitive resilience specifically in individuals with bipolar disorder. Although age impacted all neurobehavioural traits, we did not find any evidence of accelerated cognitive decline specific to bipolar disorder subjects. Regardless of diagnosis, greater global brain volume may represent a protective factor for the effects of ageing on executive functioning. PMID:25943422

  7. On the effects of assembly compression on the performance of liquid-feed DMFCs under methanol-limiting conditions: A 2D numerical study

    NASA Astrophysics Data System (ADS)

    García-Salaberri, P. A.; Vera, M.

    2015-07-01

    The influence of assembly compression on the performance of liquid-feed DMFCs under methanol-limiting conditions is explored by means of a 2D/1D multiphysics across-the-channel model. The numerical formulation incorporates a comprehensive 2D description of the anode GDL, including two-phase phenomena, non-uniform anisotropic transport properties, and electrical contact resistances at the GDL/BPP interface. GDL effective properties are evaluated using empirical data corresponding to Toray® carbon paper. A simplified but physically sound 1D description, locally coupled to the 2D anode GDL model, is adopted to describe transport processes in the MPLs, membrane and cathode GDL, whereas the catalyst layers are treated as infinitely thin surfaces. Good agreement is found between the numerical results and previous experimental data. The interplay between assembly compression, bipolar plate material, and channel configuration is also investigated. The results show that there is an optimum GDL compression ratio in terms of overall power density, the optimal compression level being strongly dependent on bipolar plate material. Beyond the optimum, the detrimental effect of compression is larger in non-parallel flow fields due to the additional reduction of methanol transported by under-rib convection. The results suggest that, under certain conditions, this transport mechanism could be more important than diffusion in the anode of liquid-feed DMFCs.

  8. Development of a Planar Heterojunction Bipolar Transistor for Very High Speed Logic.

    DTIC Science & Technology

    1983-12-01

    AD- R136 341 DEVELOPMENT OF A PLANAR HETEROJUNCTION BIPOLAR i/i TRANSISTOR FOR VERV HIGH S..(U) CALIFORNIA UNIV SANTA BARBARA DEPT OF ELECTRICAL AND...GaAs material systems . Emphasis has been placed on growth and char- acterization of the above heterojunctions by Holecular Beam Epitaxy and on the...GaAs material system is used to fabricate discrete single heterojunction bipolar transistor structures. Conventional mesa-etch tech- niques will be used

  9. Brain structure in schizophrenia vs. psychotic bipolar I disorder: A VBM study.

    PubMed

    Nenadic, Igor; Maitra, Raka; Langbein, Kerstin; Dietzek, Maren; Lorenz, Carsten; Smesny, Stefan; Reichenbach, Jürgen R; Sauer, Heinrich; Gaser, Christian

    2015-07-01

    While schizophrenia and bipolar disorder have been assumed to share phenotypic and genotypic features, there is also evidence for overlapping brain structural correlates, although it is unclear whether these relate to shared psychotic features. In this study, we used voxel-based morphometry (VBM8) in 34 schizophrenia patients, 17 euthymic bipolar I disorder patients (with a history of psychotic symptoms), and 34 healthy controls. Our results indicate that compared to healthy controls schizophrenia patients show grey matter deficits (p<0.05, FDR corrected) in medial and right dorsolateral prefrontal, as well as bilaterally in ventrolateral prefrontal and insular cortical areas, thalamus (bilaterally), left superior temporal cortex, and minor medial parietal and parietooccipital areas. Comparing schizophrenia vs. bipolar I patients (p<0.05, FDR corrected) yielded a similar pattern, however, there was an additional significant reduction in schizophrenia patients in the (posterior) hippocampus bilaterally, left dorsolateral prefrontal cortex, and left cerebellum. Compared to healthy controls, the deficits in bipolar I patients only reached significance at p<0.001 (uncorr.) for a minor parietal cluster, but not for prefrontal areas. Our results suggest that the more extensive prefrontal, thalamic, and hippocampal deficits that might set apart schizophrenia and bipolar disorder might not be related to mere appearance of psychotic symptoms at some stage of the disorders. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Multimodal Neuroimaging of Fronto-limbic Structure and Function Associated with Suicide Attempts in Adolescents and Young Adults with Bipolar Disorder

    PubMed Central

    Johnston, Jennifer A. Y.; Wang, Fei; Liu, Jie; Blond, Benjamin N.; Wallace, Amanda; Liu, Jiacheng; Spencer, Linda; Cox Lippard, Elizabeth T.; Purves, Kirstin L.; Landeros-Weisenberger, Angeli; Hermes, Eric; Pittman, Brian; Zhang, Sheng; King, Robert; Martin, Andrés; Oquendo, Maria A.; Blumberg, Hilary P.

    2018-01-01

    Objective Bipolar disorder is associated with high risk for suicide behavior that often develops in adolescence/young adulthood. Elucidation of involved neural systems is critical for prevention. This study of adolescents/young adults with bipolar disorder with and without history of suicide attempts combines structural, diffusion tensor and functional magnetic resonance imaging methods to investigate implicated abnormalities in structural and functional connectivity within fronto-limbic systems. Method Participants with bipolar disorder included 26 with a prior suicide attempt and 42 without attempts. Regional gray matter volume, white matter integrity and functional connectivity during processing of emotional stimuli were compared between groups and differences were explored for relationships between imaging modalities and associations with suicide-related symptoms and behaviors. Results Compared to the non-attempter group, the attempter group showed reductions in gray matter volume in orbitofrontal cortex, hippocampus and cerebellum; white matter integrity in uncinate fasciculus, ventral frontal and right cerebellum regions; and amygdala functional connectivity to left ventral and right rostral prefrontal cortex (p<0.05, corrected). In exploratory analyses, among attempters, right rostral prefrontal connectivity was negatively correlated with suicidal ideation (p<0.05), and left ventral prefrontal connectivity was negatively correlated with attempt lethality (p<0.05). Conclusions Adolescent/young adult suicide attempters with bipolar disorder demonstrate less gray matter volume and decreased structural and functional connectivity in a ventral fronto-limbic neural system subserving emotion regulation. Among suicide attempters, reductions in amygdala-prefrontal functional connectivity may be associated with severity of suicide ideation and attempt lethality. PMID:28135845

  11. Perceptual switch rates with ambiguous structure-from-motion figures in bipolar disorder.

    PubMed

    Krug, Kristine; Brunskill, Emma; Scarna, Antonina; Goodwin, Guy M; Parker, Andrew J

    2008-08-22

    Slowing of the rate at which a rivalrous percept switches from one configuration to another has been suggested as a potential trait marker for bipolar disorder. We measured perceptual alternations for a bistable, rotating, structure-from-motion cylinder in bipolar and control participants. In a control task, binocular depth rendered the direction of cylinder rotation unambiguous to monitor participants' performance and attention during the experimental task. A particular direction of rotation was perceptually stable, on average, for 33.5s in participants without psychiatric diagnosis. Euthymic, bipolar participants showed a slightly slower rate of switching between the two percepts (percept duration 42.3s). Under a parametric analysis of the best-fitting model for individual participants, this difference was statistically significant. However, the variability within groups was high, so this difference in average switch rates was not big enough to serve as a trait marker for bipolar disorder. We also found that low-level visual capacities, such as stereo threshold, influence perceptual switch rates. We suggest that there is no single brain location responsible for perceptual switching in all different ambiguous figures and that perceptual switching is generated by the actions of local cortical circuitry.

  12. Trait-Related Cortical-Subcortical Dissociation in Bipolar Disorder: Analysis of Network Degree Centrality.

    PubMed

    Zhou, Qian; Womer, Fay Y; Kong, Lingtao; Wu, Feng; Jiang, Xiaowei; Zhou, Yifang; Wang, Dahai; Bai, Chuan; Chang, Miao; Fan, Guoguang; Xu, Ke; He, Yong; Tang, Yanqing; Wang, Fei

    2017-05-01

    Bipolar disorder is a systemic brain disorder. Accumulated evidence suggested that cortical-subcortical imbalance could be a trait-related pathogenic factor of bipolar disorder. Degree centrality, a robust index of focal connectivity in which the number of direct connections from one node to all nodes is counted, has not previously been studied in bipolar disorder as a whole. Resting state functional magnetic resonance imaging was performed on 52 patients with DSM-IV bipolar I disorder and 70 healthy controls recruited between September 2009 and July 2014. Degree centrality was calculated within cerebral gray matter for each subject and compared between patients with bipolar disorder and healthy controls. Hub distributions of both groups were explored. Effects of medication exposure and mood state on degree centrality, as well as cortical-subcortical degree centrality correlations, were explored. Compared to healthy controls, patients with bipolar disorder exhibited significant decrease in degree centrality in cortical regions, including the middle temporal pole, inferior temporal gyrus, and ventral prefrontal cortex, but showed significant increase in degree centrality mainly in subcortical regions, including caudate, thalamus, parahippocampal gyrus, hippocampi, anterior cingulate, insula, and amygdala, and a small portion of cortical regions, such as superior and middle frontal gyrus (P < .05, corrected). Spatial distributions of the 2 groups were very similar. No significant effects of medication exposure or mood state on degree centrality were found. Patients with bipolar disorder also showed significant decrease in cortical-subcortical degree centrality correlation (P = .003). These findings further contribute to the mounting evidence of cortical-subcortical dissociation in bipolar disorder pathophysiology. In addition, this study supports the continued development and implementation of graph-based techniques to enhance our understanding of the underlying neural mechanisms in mental disorders such as bipolar disorder, which are increasingly viewed as systemic brain disorders rather than disorders arising from disruption within a single structure or a limited number of structures. Due to the heterogeneity of our sample, as well as the small sample size of each medication and mood state subgroups, further investigation is needed to support our findings. © Copyright 2016 Physicians Postgraduate Press, Inc.

  13. Linear induction accelerator

    DOEpatents

    Buttram, M.T.; Ginn, J.W.

    1988-06-21

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  14. Impact of a cis-associated gene expression SNP on chromosome 20q11.22 on bipolar disorder susceptibility, hippocampal structure and cognitive performance.

    PubMed

    Li, Ming; Luo, Xiong-jian; Landén, Mikael; Bergen, Sarah E; Hultman, Christina M; Li, Xiao; Zhang, Wen; Yao, Yong-Gang; Zhang, Chen; Liu, Jiewei; Mattheisen, Manuel; Cichon, Sven; Mühleisen, Thomas W; Degenhardt, Franziska A; Nöthen, Markus M; Schulze, Thomas G; Grigoroiu-Serbanescu, Maria; Li, Hao; Fuller, Chris K; Chen, Chunhui; Dong, Qi; Chen, Chuansheng; Jamain, Stéphane; Leboyer, Marion; Bellivier, Frank; Etain, Bruno; Kahn, Jean-Pierre; Henry, Chantal; Preisig, Martin; Kutalik, Zoltán; Castelao, Enrique; Wright, Adam; Mitchell, Philip B; Fullerton, Janice M; Schofield, Peter R; Montgomery, Grant W; Medland, Sarah E; Gordon, Scott D; Martin, Nicholas G; Rietschel, Marcella; Liu, Chunyu; Kleinman, Joel E; Hyde, Thomas M; Weinberger, Daniel R; Su, Bing

    2016-02-01

    Bipolar disorder is a highly heritable polygenic disorder. Recent enrichment analyses suggest that there may be true risk variants for bipolar disorder in the expression quantitative trait loci (eQTL) in the brain. We sought to assess the impact of eQTL variants on bipolar disorder risk by combining data from both bipolar disorder genome-wide association studies (GWAS) and brain eQTL. To detect single nucleotide polymorphisms (SNPs) that influence expression levels of genes associated with bipolar disorder, we jointly analysed data from a bipolar disorder GWAS (7481 cases and 9250 controls) and a genome-wide brain (cortical) eQTL (193 healthy controls) using a Bayesian statistical method, with independent follow-up replications. The identified risk SNP was then further tested for association with hippocampal volume (n = 5775) and cognitive performance (n = 342) among healthy individuals. Integrative analysis revealed a significant association between a brain eQTL rs6088662 on chromosome 20q11.22 and bipolar disorder (log Bayes factor = 5.48; bipolar disorder P = 5.85 × 10(-5)). Follow-up studies across multiple independent samples confirmed the association of the risk SNP (rs6088662) with gene expression and bipolar disorder susceptibility (P = 3.54 × 10(-8)). Further exploratory analysis revealed that rs6088662 is also associated with hippocampal volume and cognitive performance in healthy individuals. Our findings suggest that 20q11.22 is likely a risk region for bipolar disorder; they also highlight the informative value of integrating functional annotation of genetic variants for gene expression in advancing our understanding of the biological basis underlying complex disorders, such as bipolar disorder. © The Royal College of Psychiatrists 2016.

  15. Mechanisms underlying the benefits of anticonvulsants over lithium in the treatment of bipolar disorder.

    PubMed

    Corrado, Alisa C; Walsh, John P

    2016-02-10

    Close to 3% of the world's population suffers from bipolar disease (I and II). Of this 3%, bipolar disease affects largely women (∼ 3 : 2 compared with men). The median age of diagnosis is 25 in women and even lower in men. A diagnosis of bipolar disease is an expensive psychiatric diagnosis, costing patients more than twice as much money as a diagnosis of unipolar depression. Bipolar I is characterized by one or more manic or mixed episodes, with both mania and depression occurring each day for at least 1 week, whereas bipolar II is characterized by one or more major depressive episode and at least one episode of hypomania. Bipolar I is the more severe diagnosis. A wide range of medications are available to help patients maintain a healthy lifestyle, including lithium, antidepressants, and anticonvulsants. Improved methods for identifying bipolar disease, including a more structured approach and a more complete use of medical records, have increased the rate of diagnosis, especially in children, which underscores the need for innovation in development and in practice of new treatment options for treating bipolar disease. Although lithium has been the 'gold standard' for treating bipolar disorder for decades, new research into other forms of treatment has shown anticonvulsants to be a particularly useful therapy for treating bipolar disease. Anticonvulsants have remarkable mood-stabilization abilities and they do not lead to serious side effects, which increases the tolerability, and consequently, patient adherence to this form of treatment. Recent studies have shown that anticonvulsants improve behavior in bipolar disease by modulating the balance of excitatory and inhibitory synapses through a number of complementary molecular cascades that affect gene expression and cell survival.

  16. ON Cone Bipolar Cell Axonal Synapses in the OFF Inner Plexiform Layer of the Rabbit Retina

    PubMed Central

    Lauritzen, J. Scott; Anderson, James R.; Jones, Bryan W.; Watt, Carl B.; Mohammed, Shoeb; Hoang, John V.; Marc, Robert E.

    2012-01-01

    Analysis of the rabbit retinal connectome RC1 reveals that the division between the ON and OFF inner plexiform layer (IPL) is not structurally absolute. ON cone bipolar cells make non-canonical axonal synapses onto specific targets and receive amacrine cell synapses in the nominal OFF layer, creating novel motifs, including inhibitory crossover networks. Automated transmission electron microscope (ATEM) imaging, molecular tagging, tracing, and rendering of ≈ 400 bipolar cells reveals axonal ribbons in 36% of ON cone bipolar cells, throughout the OFF IPL. The targets include GABA-positive amacrine cells (γACs), glycine-positive amacrine cells (GACs) and ganglion cells. Most ON cone bipolar cell axonal contacts target GACs driven by OFF cone bipolar cells, forming new architectures for generating ON-OFF amacrine cells. Many of these ON-OFF GACs target ON cone bipolar cell axons, ON γACs and/or ON-OFF ganglion cells, representing widespread mechanisms for OFF to ON crossover inhibition. Other targets include OFF γACs presynaptic to OFF bipolar cells, forming γAC-mediated crossover motifs. ON cone bipolar cell axonal ribbons drive bistratified ON-OFF ganglion cells in the OFF layer and provide ON drive to polarity-appropriate targets such as bistratified diving ganglion cells (bsdGCs). The targeting precision of ON cone bipolar cell axonal synapses shows that this drive incidence is necessarily a joint distribution of cone bipolar cell axonal frequency and target cell trajectories through a given volume of the OFF layer. Such joint distribution sampling is likely common when targets are sparser than sources and when sources are coupled, as are ON cone bipolar cells. PMID:23042441

  17. Planar solid oxide fuel cell with staged indirect-internal air and fuel preheating and reformation

    DOEpatents

    Geisbrecht, Rodney A; Williams, Mark C

    2003-10-21

    A solid oxide fuel cell arrangement and method of use that provides internal preheating of both fuel and air in order to maintain the optimum operating temperature for the production of energy. The internal preheat passes are created by the addition of two plates, one on either side of the bipolar plate, such that these plates create additional passes through the fuel cell. This internal preheat fuel cell configuration and method reduce the requirements for external heat exchanger units and air compressors. Air or fuel may be added to the fuel cell as required to maintain the optimum operating temperature through a cathode control valve or an anode control valve, respectively. A control loop comprises a temperature sensing means within the preheat air and fuel passes, a means to compare the measured temperature to a set point temperature and a determination based on the comparison as to whether the control valves should allow additional air or fuel into the preheat or bypass manifolds of the fuel cell.

  18. Identifying early indicators in bipolar disorder: a qualitative study.

    PubMed

    Benti, Liliane; Manicavasagar, Vijaya; Proudfoot, Judy; Parker, Gordon

    2014-06-01

    The identification of early markers has become a focus for early intervention in bipolar disorder. Using a retrospective, qualitative methodology, the present study compares the early experiences of participants with bipolar disorder to those with unipolar depression up until their first diagnosed episode. The study focuses on differences in early home and school environments as well as putative differences in personality characteristics between the two groups. Finally we a compare and contrast prodromal symptoms in these two populations. Thirty-nine participants, 20 diagnosed with unipolar depression and 19 diagnosed with bipolar disorder, took part in the study. A semi-structured interview was developed to elicit information about participants' experiences prior to their first episode. Participants with bipolar disorder reported disruptive home environments, driven personality features, greater emotion dysregulation and adverse experiences during the school years, whereas participants with depression tended to describe more supportive home environments, and more compliant and introvert personality traits. Retrospective data collection and no corroborative evidence from other family members. No distinction was made between bipolar I and bipolar II disorder nor between melancholic and non-melancholic depression in the sample. Finally the study spanned over a 12-month period which does not allow for the possibility of diagnostic reassignment of some of the bipolar participants to the unipolar condition. These findings indicate that there may be benefits in combining both proximal and distal indicators in identifying a bipolar disorder phenotype which, in turn, may be relevant to the development of early intervention programs for young people with bipolar disorder.

  19. A compact bipolar pulse-forming network-Marx generator based on pulse transformers.

    PubMed

    Zhang, Huibo; Yang, Jianhua; Lin, Jiajin; Yang, Xiao

    2013-11-01

    A compact bipolar pulse-forming network (PFN)-Marx generator based on pulse transformers is presented in this paper. The high-voltage generator consisted of two sets of pulse transformers, 6 stages of PFNs with ceramic capacitors, a switch unit, and a matched load. The design is characterized by the bipolar pulse charging scheme and the compact structure of the PFN-Marx. The scheme of bipolar charging by pulse transformers increased the withstand voltage of the ceramic capacitors in the PFNs and decreased the number of the gas gap switches. The compact structure of the PFN-Marx was aimed at reducing the parasitic inductance in the generator. When the charging voltage on the PFNs was 35 kV, the matched resistive load of 48 Ω could deliver a high-voltage pulse with an amplitude of 100 kV. The full width at half maximum of the load pulse was 173 ns, and its rise time was less than 15 ns.

  20. New materials for polymer electrolyte membrane fuel cell current collectors

    NASA Astrophysics Data System (ADS)

    Hentall, Philip L.; Lakeman, J. Barry; Mepsted, Gary O.; Adcock, Paul L.; Moore, Jon M.

    Polymer Electrolyte Membrane Fuel cells for automotive applications need to have high power density, and be inexpensive and robust to compete effectively with the internal combustion engine. Development of membranes and new electrodes and catalysts have increased power significantly, but further improvements may be achieved by the use of new materials and construction techniques in the manufacture of the bipolar plates. To show this, a variety of materials have been fabricated into flow field plates, both metallic and graphitic, and single fuel cell tests were conducted to determine the performance of each material. Maximum power was obtained with materials which had lowest contact resistance and good electrical conductivity. The performance of the best material was characterised as a function of cell compression and flow field geometry.

  1. Metrology for Fuel Cell Manufacturing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stocker, Michael; Stanfield, Eric

    2015-02-04

    The project was divided into three subprojects. The first subproject is Fuel Cell Manufacturing Variability and Its Impact on Performance. The objective was to determine if flow field channel dimensional variability has an impact on fuel cell performance. The second subproject is Non-contact Sensor Evaluation for Bipolar Plate Manufacturing Process Control and Smart Assembly of Fuel Cell Stacks. The objective was to enable cost reduction in the manufacture of fuel cell plates by providing a rapid non-contact measurement system for in-line process control. The third subproject is Optical Scatterfield Metrology for Online Catalyst Coating Inspection of PEM Soft Goods. Themore » objective was to evaluate the suitability of Optical Scatterfield Microscopy as a viable measurement tool for in situ process control of catalyst coatings.« less

  2. [Differences in Subjective Experience Between Unipolar and Bipolar Depression].

    PubMed

    Fierro, Marco; Bustos, Andrés; Molina, Carlos

    2016-01-01

    It is important to make distinction between bipolar and unipolar depression because treatment and prognosis are different. Since the diagnosis of the two conditions is purely clinical, find symptomatic differences is useful. Find differences in subjective experience (first person) between unipolar and bipolar depression. Phenomenological-oriented qualitative exploratory study of 12 patients (7 with bipolar depression and 5 with unipolar depression, 3 men and 9 women). We used a semi-structured interview based on Examination of Anomalous Self-Experience (EASE). The predominant mood in bipolar depression is emotional dampening, in unipolar is sadness. The bodily experience in bipolar is of a heavy, tired body; an element that inserts between the desires of acting and performing actions and becomes an obstacle to the movement. In unipolar is of a body that feels more comfortable with the stillness than activity, like laziness of everyday life. Cognition and the stream of consciousness: in bipolar depression, compared with unipolar, thinking is slower, as if to overcome obstacles in their course. There are more difficult to understand what is heard or read. Future perspective: in bipolar depression, hopelessness is stronger and broader than in unipolar, as if the very possibility of hope was lost. Qualitative differences in predominant mood, bodily experience, cognition and future perspective were found between bipolar and unipolar depression. Copyright © 2015 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  3. Bipolar disorder: a neural network perspective on a disorder of emotion and motivation.

    PubMed

    Wessa, Michèle; Kanske, Philipp; Linke, Julia

    2014-01-01

    Bipolar disorder (BD) is a severe, chronic disease with a heritability of 60-80%. BD is frequently misdiagnosed due to phenomenological overlap with other psychopathologies, an important issue that calls for the identification of biological and psychological vulnerability and disease markers. Altered structural and functional connectivity, mainly between limbic and prefrontal brain areas, have been proposed to underlie emotional and motivational dysregulation in BD and might represent relevant vulnerability and disease markers. In the present laboratory review we discuss functional and structural neuroimaging findings on emotional and motivational dysregulation from our research group in BD patients and healthy individuals at risk to develop BD. As a main result of our studies, we observed altered orbitofrontal and limbic activity and reduced connectivity between dorsal prefrontal and limbic brain regions, as well as reduced integrity of fiber tracts connecting prefrontal and subcortical brain structures in BD patients and high-risk individuals. Our results provide novel insights into pathophysiological mechanisms of bipolar disorder. The current laboratory review provides a specific view of our group on altered brain connectivity and underlying psychological processes in bipolar disorder based on our own work, integrating relevant findings from others. Thereby we attempt to advance neuropsychobiological models of BD.

  4. Linear induction accelerator and pulse forming networks therefor

    DOEpatents

    Buttram, Malcolm T.; Ginn, Jerry W.

    1989-01-01

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities.

  5. A New Electrospray Aerosol Generator with High Particle Transmission Efficiency

    PubMed Central

    Fu, Huijing; Patel, Anand C.; Holtzman, Michael J.; Chen, Da-Ren

    2012-01-01

    A new single-capillary electrospray (ES) aerosol generator has been developed for monodisperse particle production with maximal transmission efficiency. The new generator consists of both a spray chamber in a point-to-orifice-plate configuration and a charge reduction chamber that can hold up to 4 Nuclespot ionizers (Model P-2042, NRD Inc.). The 2 chambers are partitioned by an orifice plate. To optimize the particle transmission efficiency of the prototype, a systematic study was performed on the generator by varying the system setup and operation. Two key dimensions of the generator setup, the orifice diameter and the distance from the capillary tip to the orifice plate, were varied. Fluorescence analysis was applied to characterize the loss of ES-generated particles at different locations of the prototype. It was found that particle loss in the generator could be reduced by either increasing the orifice diameter or decreasing the distance between the capillary tip and the orifice plate. Increasing either the total radioactivity of the ionizers or the flowrate of the particle carrier gas also further decreased the particle loss in the system. The maximum particle transmission efficiency of 88.0% was obtained with the spray chamber fully opened to the charge reduction chamber, the capillary tip at the same level as the orifice plate, and 4 bipolar ionizers installed. PMID:22829715

  6. Use of bipolar radiofrequency catheter ablation in treatment of cardiac arrhythmias.

    PubMed

    Soucek, Filip; Starek, Zdenek

    2018-05-23

    Background Arrhythmia management is a complex process involving both pharmacological and non-pharmacological approaches. Radiofrequency ablation is the pillar of non-pharmacological arrhythmia treatment. Unipolar ablation is considered to be the gold standard in the treatment of the majority of arrhythmias; however, its efficacy is limited to specific cases. In particular, the creation of deep or transmural lesions to eliminate intramurally originating arrhythmias remains inadequate. Bipolar ablation is proposed as an alternative to overcome unipolar ablation boundaries. Results Despite promising results gained from in vitro and animal studies showing that bipolar ablation is superior in creating transmural lesions, the use of bipolar ablation in daily clinical practice is limited. Several studies have been published showing that bipolar ablation is effective in the treatment of clinical arrhythmias after failed unipolar ablation, however there is inconsistency regarding safety of bipolar ablation within the available research papers. According to research evidence the most common indications for bipolar ablation use are ventricular originating rhythmic disorders in patients with structural heart disease resistant to standard radiofrequency ablation. Conclusions To allow wider clinical application the efficiency and safety of bipolar ablation need to be verified in future studies. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Status of commercial phosphoric acid fuel cell system development

    NASA Technical Reports Server (NTRS)

    Warshay, M.; Prokopius, P. R.; Simons, S. N.; King, R. B.

    1981-01-01

    In both the electric utility and onsite integrated energy system applications, reducing cost and increasing reliability are the main technology drivers. The longstanding barrier to the attainment of these goals, which manifests itself in a number of ways, was materials. The differences in approach among the three major participants (United Technologies Corporation, Westinghouse Electric Corporation/Energy Research Corporation, and Engelhard Industries) and their unique technological features, including electrodes, matrices, intercell cooling, bipolar/separator plates, electrolyte management, fuel selection and system design philosophy are discussed.

  8. Technology development for phosphoric acid fuel cell powerplant, phase 2

    NASA Technical Reports Server (NTRS)

    Christner, L.

    1979-01-01

    A technique for producing an acid inventory control member by spraying FEP onto a partially screened carbon paper backing is discussed. Theoretical analysis of the acid management indicates that the vapor composition of 103% H3PO4 is approximately 1.0 ppm P4O10. An SEM evaluation of corrosion resistance of phenolic resins and graphite/phenolic resin composites in H3PO4 at 185 C shows specific surface etching. Carbonization of graphite/phenolic bipolar plates is achieved without blistering.

  9. A new lead-acid battery for high pulse power applications

    NASA Technical Reports Server (NTRS)

    Rowlette, J. J.; Attia, A. I.

    1987-01-01

    The development of new electronically conductive materials which can withstand the environment of the positive plates has made possible the construction of a high pulse power sealed bipolar lead-acid battery. The new battery is described and its advantages over other electrochemical systems are outlined. Performance projections show that the peak specific power of the battery can be as high as 90 kW/kg, and that a specific power of 5 kW/kg can be sustained over several thousand pulses.

  10. Asia Pacific Research Initiative for Sustainable Energy Systems 2011 (APRISES11)

    DTIC Science & Technology

    2017-09-29

    created during a single run , highlighting rapid prototyping capabilities. NRL’s overall goal was to evaluate whether 3D printed metallic bipolar plates...varying the air flow to evaluate the effect on peak power. These runs are displayed in Figure 2.1.17. The reactants were connected in co-flow with the...way valve allows the operator to either run the gas through a humidifier (PermaPure Model FCl 25-240-7) or a bypass loop. On the humidifier side of

  11. Mapping vulnerability to bipolar disorder: a systematic review and meta-analysis of neuroimaging studies

    PubMed Central

    Fusar-Poli, Paolo; Howes, Oliver; Bechdolf, Andreas; Borgwardt, Stefan

    2012-01-01

    Background Although early interventions in individuals with bipolar disorder may reduce the associated personal and economic burden, the neurobiologic markers of enhanced risk are unknown. Methods Neuroimaging studies involving individuals at enhanced genetic risk for bipolar disorder (HR) were included in a systematic review. We then performed a region of interest (ROI) analysis and a whole-brain meta-analysis combined with a formal effect-sizes meta-analysis in a subset of studies. Results There were 37 studies included in our systematic review. The overall sample for the systematic review included 1258 controls and 996 HR individuals. No significant differences were detected between HR individuals and controls in the selected ROIs: striatum, amygdala, hippocampus, pituitary and frontal lobe. The HR group showed increased grey matter volume compared with patients with established bipolar disorder. The HR individuals showed increased neural response in the left superior frontal gyrus, medial frontal gyrus and left insula compared with controls, independent from the functional magnetic resonance imaging task used. There were no publication biases. Sensitivity analysis confirmed the robustness of these results. Limitations As the included studies were cross-sectional, it remains to be determined whether the observed neurofunctional and structural alterations represent risk factors that can be clinically used in preventive interventions for prodromal bipolar disorder. Conclusion Accumulating structural and functional imaging evidence supports the existence of neurobiologic trait abnormalities in individuals at genetic risk for bipolar disorder at various scales of investigation. PMID:22297067

  12. Beyond bipolar conceptualizations and measures: the case of attitudes and evaluative space.

    PubMed

    Cacioppo, J T; Gardner, W L; Berntson, G G

    1997-01-01

    All organisms must be capable of differentiating hostile from hospitable stimuli to survive. Typically, this evaluative discrimination is conceptualized as being bipolar (hostile-hospitable). This conceptualization is certainly evident in the area of attitudes, where the ubiquitous bipolar attitude measure, by gauging the net affective predisposition toward a stimulus, treats positive and negative evaluative processes as equivalent, reciprocally activated, and interchangeable. Contrary to conceptualizations of this evaluative process as bipolar, recent evidence suggests that distinguishable motivational systems underlie assessments of the positive and negative significance of a stimulus. Thus, a stimulus may vary in terms of the strength of positive evaluative activation and the strength of negative evaluative activation it evokes. Low activation of positive and negative evaluative processes by a stimulus reflects attitude neutrality or indifference, whereas high activation of positive and negative evaluative processes reflects attitude ambivalence. As such, attitudes can be represented more completely within a bivariate space than along a bipolar continuum. Evidence is reviewed showing that the positive and negative evaluative processes underlying many attitudes are distinguishable (stochastically and functionally independent), are characterized by distinct activation functions (positivity offset and negativity bias principles), are related differentially to attitude ambivalence (corollary of ambivalence asymmetries), have distinguishable antecedents (heteroscedacity principle), and tend to gravitate from a bivariate toward a bipolar structure when the underlying beliefs are the target of deliberation or a guide for behavior (principle of motivational certainty). The implications for society phenomena such as political elections and democratic structures are discussed.

  13. Sleep loss as a trigger of mood episodes in bipolar disorder: individual differences based on diagnostic subtype and gender.

    PubMed

    Lewis, Katie Swaden; Gordon-Smith, Katherine; Forty, Liz; Di Florio, Arianna; Craddock, Nick; Jones, Lisa; Jones, Ian

    2017-09-01

    Background Sleep loss may trigger mood episodes in people with bipolar disorder but individual differences could influence vulnerability to this trigger. Aims To determine whether bipolar subtype (bipolar disorder type I (BP-I) or II (BD-II)) and gender were associated with vulnerability to the sleep loss trigger. Method During a semi-structured interview, 3140 individuals (68% women) with bipolar disorder (66% BD-I) reported whether sleep loss had triggered episodes of high or low mood. DSM-IV diagnosis of bipolar subtype was derived from case notes and interview data. Results Sleep loss triggering episodes of high mood was associated with female gender (odds ratio (OR) = 1.43, 95% CI 1.17-1.75, P < 0.001) and BD-I subtype (OR = 2.81, 95% CI 2.26-3.50, P < 0.001). Analyses on sleep loss triggering low mood were not significant following adjustment for confounders. Conclusions Gender and bipolar subtype may increase vulnerability to high mood following sleep deprivation. This should be considered in situations where patients encounter sleep disruption, such as shift work and international travel. © The Royal College of Psychiatrists 2017.

  14. Bipolar patients' quality of life in mixed states: a preliminary qualitative study.

    PubMed

    Lee Mortensen, Gitte; Vinberg, Maj; Lee Mortensen, Steen; Balslev Jørgensen, Martin; Eberhard, Jonas

    2015-01-01

    Approximately 20% of patients with bipolar disorder experience mixed states. Mixed states are associated with more comorbidity, poorer treatment response and prognosis, increased relapse rate, and decreased functioning. This study aimed to produce in-depth knowledge about bipolar patients' quality of life (QoL) and functioning related to mixed states. This study used qualitative research methods. A semi-structured interview guide based on a literature study was applied in interviews with 6 remitted bipolar I patients having experienced mixed states. A medical anthropological approach was applied to analyse the data. Participants described mixed states as worse than other bipolar disorder states and their residual symptoms were prolonged. Mixed states affected the functioning of patients in key life domains such as self-esteem, family, love and social life, physical well-being, and working capability. Mixed states may severely affect the QoL and functioning of bipolar patients. Our results indicate that improving these should be a main goal of patient treatment. With an aim of adequately identifying and treating mixed states, our findings highlight the need for knowledge about this particularly severe expression of bipolar disorder. These results should be confirmed in a larger sample of patients with varying socioeconomic status.

  15. Sleep loss as a trigger of mood episodes in bipolar disorder: individual differences based on diagnostic subtype and gender

    PubMed Central

    Lewis, Katie Swaden; Gordon-Smith, Katherine; Forty, Liz; Di Florio, Arianna; Craddock, Nick; Jones, Lisa; Jones, Ian

    2017-01-01

    Background Sleep loss may trigger mood episodes in people with bipolar disorder but individual differences could influence vulnerability to this trigger. Aims To determine whether bipolar subtype (bipolar disorder type I (BP-I) or II (BD-II)) and gender were associated with vulnerability to the sleep loss trigger. Method During a semi-structured interview, 3140 individuals (68% women) with bipolar disorder (66% BD-I) reported whether sleep loss had triggered episodes of high or low mood. DSM-IV diagnosis of bipolar subtype was derived from case notes and interview data. Results Sleep loss triggering episodes of high mood was associated with female gender (odds ratio (OR) = 1.43, 95% CI 1.17–1.75, P < 0.001) and BD-I subtype (OR = 2.81, 95% CI 2.26–3.50, P < 0.001). Analyses on sleep loss triggering low mood were not significant following adjustment for confounders. Conclusions Gender and bipolar subtype may increase vulnerability to high mood following sleep deprivation. This should be considered in situations where patients encounter sleep disruption, such as shift work and international travel. PMID:28684405

  16. Screening for bipolar disorders in Spanish-speaking populations: sensitivity and specificity of the Bipolar Spectrum Diagnostic Scale-Spanish Version.

    PubMed

    Vázquez, Gustavo Héctor; Romero, Ester; Fabregues, Fernando; Pies, Ronald; Ghaemi, Nassir; Mota-Castillo, Manuel

    2010-01-01

    Bipolar disorder is commonly misdiagnosed, perhaps more so in Latin American and Spanish-speaking populations than in the United States. The Bipolar Spectrum Diagnostic Scale (BSDS) is a 19-item screening instrument designed to assist in screening for all types of bipolar disorder. The authors investigated the sensitivity of a Spanish-language version of the BSDS in a cohort of 65 outpatients with a diagnosis of bipolar disorder, based on a semi-structured interview and Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria. To determine specificity, we assessed a control group of 36 outpatients with diagnosis of unipolar major depressive disorder. The overall sensitivity of the BSDS Spanish version with bipolar disorders types I, II, and NOS was 0.70, which was slightly lower than the sensitivity in the study using the English version of the BSDS (0.76). The specificity was 0.89. When the threshold was decreased from 13 to 12, the sensitivity of the Spanish BSDS increased to 0.76 and specificity dropped to 0.81. The Spanish version of the BSDS is promising as a screening instrument in Spanish-speaking populations. Copyright 2010 Elsevier Inc. All rights reserved.

  17. A critical appraisal of neuroimaging studies of bipolar disorder: toward a new conceptualization of underlying neural circuitry and roadmap for future research

    PubMed Central

    Phillips, Mary L; Swartz, Holly A.

    2014-01-01

    Objective This critical review appraises neuroimaging findings in bipolar disorder in emotion processing, emotion regulation, and reward processing neural circuitry, to synthesize current knowledge of the neural underpinnings of bipolar disorder, and provide a neuroimaging research “roadmap” for future studies. Method We examined findings from all major studies in bipolar disorder that used fMRI, volumetric analyses, diffusion imaging, and resting state techniques, to inform current conceptual models of larger-scale neural circuitry abnormalities in bipolar disorder Results Bipolar disorder can be conceptualized in neural circuitry terms as parallel dysfunction in bilateral prefrontal cortical (especially ventrolateral prefrontal cortical)-hippocampal-amygdala emotion processing and emotion regulation neural circuitries, together with an “overactive” left-sided ventral striatal-ventrolateral and orbitofrontal cortical reward processing circuitry, that result in characteristic behavioral abnormalities associated with bipolar disorder: emotional lability, emotional dysregulation and heightened reward sensitivity. A potential structural basis for these functional abnormalities are gray matter decreases in prefrontal and temporal cortices, amygdala and hippocampus, and fractional anisotropy decreases in white matter tracts connecting prefrontal and subcortical regions. Conclusion Neuroimaging studies of bipolar disorder clearly demonstrate abnormalities in neural circuitries supporting emotion processing, emotion regulation and reward processing, although there are several limitations to these studies. Future neuroimaging research in bipolar disorder should include studies adopting dimensional approaches; larger studies examining neurodevelopmental trajectories in bipolar disorder and at-risk youth; multimodal neuroimaging studies using integrated systems approaches; and studies using pattern recognition approaches to provide clinically useful, individual-level data. Such studies will help identify clinically-relevant biomarkers to guide diagnosis and treatment decision-making for individuals with bipolar disorder. PMID:24626773

  18. Bipolar disorder and the risk of fracture: A nationwide population-based cohort study.

    PubMed

    Su, Jian-An; Cheng, Bi-Hua; Huang, Yin-Cheng; Lee, Chuan-Pin; Yang, Yao-Hsu; Lu, Mong-Liang; Hsu, Chung-Yao; Lee, Yena; McIntyre, Roger S; Chin Lin, Tzu; Chin-Hung Chen, Vincent

    2017-08-15

    The co-primary aims are: 1) to compare the risk of fracture between adults with bipolar disorder and those without bipolar disorder; and 2) to assess whether lithium, anticonvulsants and antipsychotics reduce risk of fracture among individuals with bipolar disorder. The analysis herein is a population-based retrospective cohort study, utilizing the National Health Insurance (NHI) medical claims data collected between 1997 and 2013 in Taiwan. We identified 3705 cases with incident diagnoses of bipolar disorder during study period and 37,050 matched controls without bipolar diagnoses. Incident diagnosis of fracture was operationalized as any bone fracture after the diagnosis of bipolar disorder or after the matched index date for controls. Bipolar patients had significantly higher risk of facture when compared to matched controls (17.6% versus 11.7%, respectively p<0.001). The hazard ratio (HR) was 1.33 (95% confidence interval [CI]=1.23-1.48, p<0.001) after adjusting for covariates. Persons with bipolar disorder and a prior history of psychiatric hospitalization were had higher risk for bone fracture than those without prior history of psychiatric hospitalization when compared to match controls. Higher cumulative dose of antipsychotics or mood stabilizers did not increase the risk of fracture. The diagnoses of bipolar disorder were not confirmed with structured clinical interview. Drug adherence, exact exposure dosage, smoking, lifestyle, nutrition and exercise habits were unable to be assessed in our dataset. Bipolar disorder is associated with increased risk of fracture, and higher cumulative dose of mood stabilizers and antipsychotics did not further increase the risk of fracture. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The bipolar assembly domain of the mitotic motor kinesin-5

    PubMed Central

    Acar, Seyda; Carlson, David B.; Budamagunta, Madhu S.; Yarov-Yarovoy, Vladimir; Correia, John J.; Niñonuevo, Milady R.; Jia, Weitao; Tao, Li; Leary, Julie A.; Voss, John C.; Evans, James E.; Scholey, Jonathan M.

    2013-01-01

    An outstanding unresolved question is how does the mitotic spindle utilize microtubules and mitotic motors to coordinate accurate chromosome segregation during mitosis? This process depends upon the mitotic motor, kinesin-5, whose unique bipolar architecture, with pairs of motor domains lying at opposite ends of a central rod, allows it to crosslink microtubules within the mitotic spindle and to coordinate their relative sliding during spindle assembly, maintenance and elongation. The structural basis of kinesin-5’s bipolarity is, however, unknown, as protein asymmetry has so far precluded its crystallization. Here we use electron microscopy of single molecules of kinesin-5 and its subfragments, combined with hydrodynamic analysis plus mass spectrometry, circular dichroism and site-directed spin label electron paramagnetic resonance spectroscopy, to show how a staggered antiparallel coiled-coil ‘BASS’ (bipolar assembly) domain directs the assembly of four kinesin-5 polypeptides into bipolar minifilaments. PMID:23299893

  20. Magnetohydrodynamic models of bipolar knotty jet in henize 2-90

    NASA Technical Reports Server (NTRS)

    Lee, C.; Sahai, R.

    2004-01-01

    A remarkably linear, bipolar, knotty jet was recently discovered in Hen 2-90, an object classified as a young planetary nebula. Using two-dimensional, magnetohydrodynamic simulations, we investigate periodic variations in jet density and velocity as the mechanism for producing the jet and its knotty structures.

  1. High temperature oxidation resistance of magnetron-sputtered homogeneous CrAlON coatings on 430 steel

    NASA Astrophysics Data System (ADS)

    Garratt, E.; Wickey, K. J.; Nandasiri, M. I.; Moore, A.; AlFaify, S.; Gao, X.; Kayani, A.; Smith, R. J.; Buchanan, T. L.; Priyantha, W.; Kopczyk, M.; Gannon, P. E.

    2009-11-01

    The requirements of low cost and high-temperature corrosion resistance for bipolar interconnect plates in solid oxide fuel cell stacks has directed attention to the use of metal plates with oxidation resistant coatings. We have investigated the performance of steel plates with homogenous coatings of CrAlON (oxynitrides). The coatings were deposited using RF magnetron sputtering, with Ar as a sputtering gas. Oxygen in these coatings was not intentionally added. Oxygen might have come through contaminated nitrogen gas bottle, leak in the chamber or from the partial pressure of water vapors. Nitrogen was added during the growth process to get oxynitride coating. The Cr/Al composition ratio in the coatings was varied in a combinatorial approach. The coatings were subsequently annealed in air for up to 25 hours at 800 oC. The composition of the coated plates and the rate of oxidation were characterized using Rutherford backscattering (RBS) and nuclear reaction analysis (NRA). Surface characterization was carried out using Atomic Force Microscopy (AFM) and surfaces of the coatings were found smooth on submicron scale. From our results, we conclude that Al rich coatings are more susceptible to oxidation than Cr rich coatings.

  2. Prevalence and correlates of bipolar disorders in patients with eating disorders.

    PubMed

    Tseng, Mei-Chih Meg; Chang, Chin-Hao; Chen, Kuan-Yu; Liao, Shih-Cheng; Chen, Hsi-Chung

    2016-01-15

    To investigate the prevalence and correlates of bipolar disorders in patients with eating disorders (EDs), and to examine differences in effects between major depressive disorder and bipolar disorder on these patients. Sequential attendees were invited to participate in a two-phase survey for EDs at the general psychiatric outpatient clinics. Patients diagnosed with EDs (n=288) and controls of comparable age, sex, and educational level (n=81) were invited to receive structured interviews for psychiatric co-morbidities, suicide risks, and functional level. All participants also completed several self-administered questionnaires assessing general and eating-related pathology and impulsivity. Characteristics were compared between the control, ED-only, ED with major depressive disorder, and ED with bipolar disorder groups. Patients with all ED subtypes had significantly higher rates of major depressive disorder (range, 41.3-66.7%) and bipolar disorder (range, 16.7-49.3%) than controls did. Compared to patients with only EDs, patients with comorbid bipolar disorder and those with comorbid major depressive disorder had significantly increased suicidality and functional impairments. Moreover, the group with comorbid bipolar disorder had increased risks of weight dysregulation, more impulsive behaviors, and higher rates of psychiatric comorbidities. Participants were selected in a tertiary center of a non-Western country and the sample size of individuals with bipolar disorder in some ED subtypes was small. Bipolar disorders were common in patients with EDs. Careful differentiation between bipolar disorder and major depressive disorder in patients with EDs may help predict associated psychopathology and provide accurate treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Resistive switching: An investigation of the bipolar–unipolar transition in Co-doped ZnO thin films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Santos, Daniel A.A., E-mail: danielandrade.ufs@gmail.com; Department of Physics, University at Buffalo, The State University of New York, Buffalo, NY 14260; Zeng, Hao

    2015-06-15

    Highlights: • A purely bipolar behavior on a Co-doped ZnO thin film has been demonstrated. • We have shown what can happen if a unipolar test is performed in a purely bipolar device. • An explanation for how a sample can show a purely bipolar switching behavior was suggested. • An important open issue about resistive switching effect was put in debate. - Abstract: In order to investigate the resistive switching effect we built devices in a planar structure in which two Al contacts were deposited on the top of the film and separated by a small gap using amore » shadow mask. Therefore, two samples of 10% Co-doped ZnO thin films were sputtered on glass substrate. High resolution X-ray diffraction (HRXRD) revealed a highly c-axis oriented crystalline structure, without secondary phase. The high resolution scanning electron microscopy (HRSEM) showed a flat surface with good coverage and thickness about 300 nm. A Keithley 2425 semiconductor characterization system was used to perform the resistive switching tests in the bipolar and unipolar modes. Considering only the effect of compliance current (CC), the devices showed a purely bipolar behavior since an increase in CC did not induce a transition to unipolar behavior.« less

  4. Bipolar disorder diagnosis: challenges and future directions

    PubMed Central

    Phillips, Mary L; Kupfer, David J

    2018-01-01

    Bipolar disorder refers to a group of affective disorders, which together are characterised by depressive and manic or hypomanic episodes. These disorders include: bipolar disorder type I (depressive and manic episodes: this disorder can be diagnosed on the basis of one manic episode); bipolar disorder type II (depressive and hypomanic episodes); cyclothymic disorder (hypomanic and depressive symptoms that do not meet criteria for depressive episodes); and bipolar disorder not otherwise specified (depressive and hypomanic-like symptoms that do not meet the diagnostic criteria for any of the aforementioned disorders). Bipolar disorder type II is especially difficult to diagnose accurately because of the difficulty in differentiation of this disorder from recurrent unipolar depression (recurrent depressive episodes) in depressed patients. The identification of objective biomarkers that represent pathophysiologic processes that differ between bipolar disorder and unipolar depression can both inform bipolar disorder diagnosis and provide biological targets for the development of new and personalised treatments. Neuroimaging studies could help the identification of biomarkers that differentiate bipolar disorder from unipolar depression, but the problem in detection of a clear boundary between these disorders suggests that they might be better represented as a continuum of affective disorders. Innovative combinations of neuroimaging and pattern recognition approaches can identify individual patterns of neural structure and function that accurately ascertain where a patient might lie on a behavioural scale. Ultimately, an integrative approach, with several biological measurements using different scales, could yield patterns of biomarkers (biosignatures) to help identify biological targets for personalised and new treatments for all affective disorders. PMID:23663952

  5. Genetic structure of personality factors and bipolar disorder in families segregating bipolar disorder.

    PubMed

    Hare, Elizabeth; Contreras, Javier; Raventos, Henriette; Flores, Deborah; Jerez, Alvaro; Nicolini, Humberto; Ontiveros, Alfonso; Almasy, Laura; Escamilla, Michael

    2012-02-01

    Bipolar disorder (BPD) has been associated with variations in personality dimensions, but the nature of this relationship has been unclear. In this study, the heritabilities of BPD and the Big Five personality factors and the genetic correlations between BPD and personality factors are reported. The participants in this study were 1073 individuals from 172 families of Mexican or Central American ancestry. Heritabilities and genetic correlations were calculated under a polygenic model using the maximum-likelihood method of obtaining variance components implemented in the SOLAR software package. Heritabilities of 0.49, 0.43, and 0.43 were found for the narrowest phenotype (schizoaffective bipolar and bipolar I), the intermediate phenotype (schizoaffective bipolar, bipolar I, and bipolar II), and the broadest phenotype (schizoaffective bipolar, bipolar I, bipolar II, and recurrent depression), respectively. For the Big Five personality factors, heritabilities were 0.25 for agreeableness, 0.24 for conscientiousness, 0.24 for extraversion, 0.23 for neuroticism, and 0.32 for openness to experience. For the narrowest phenotype, a significant negative correlation (-0.32) with extraversion was found. For the broadest phenotype, negative correlations were found for agreeableness (-0.35), conscientiousness (-0.39), and extraversion (-0.44). A positive correlation (0.37) was found with neuroticism. It is not possible to determine whether aspects of personality are factors in the development of bipolar disorder or vice versa. The short form of the NEO does not provide the ability to examine in detail which facets of extraversion are most closely related to bipolar disorder or to compare our results with studies that have used the long version of the scale. This study establishes a partial genetic basis for the Big Five personality factors in this set of families, while the environmental variances demonstrate that non-genetic factors are also important in their influence on bipolar and personality phenotypes. BPD may be most associated with decreased extraversion (less interaction with one's surroundings) because patients spend more time in depressive than manic states. Copyright © 2011. Published by Elsevier B.V.

  6. Structural and functional changes in the somatosensory cortex in euthymic females with bipolar disorder.

    PubMed

    Minuzzi, Luciano; Syan, Sabrina K; Smith, Mara; Hall, Alexander; Hall, Geoffrey Bc; Frey, Benicio N

    2017-12-01

    Current evidence from neuroimaging data suggests possible dysfunction of the fronto-striatal-limbic circuits in individuals with bipolar disorder. Somatosensory cortical function has been implicated in emotional recognition, risk-taking and affective responses through sensory modalities. This study investigates anatomy and function of the somatosensory cortex in euthymic bipolar women. In total, 68 right-handed euthymic women (bipolar disorder = 32 and healthy controls = 36) between 16 and 45 years of age underwent high-resolution anatomical and functional magnetic resonance imaging during the mid-follicular menstrual phase. The somatosensory cortex was used as a seed region for resting-state functional connectivity analysis. Voxel-based morphometry was used to evaluate somatosensory cortical gray matter volume between groups. We found increased resting-state functional connectivity between the somatosensory cortex and insular cortex, inferior prefrontal gyrus and frontal orbital cortex in euthymic bipolar disorder subjects compared to healthy controls. Voxel-based morphometry analysis showed decreased gray matter in the left somatosensory cortex in the bipolar disorder group. Whole-brain voxel-based morphometry analysis controlled by age did not reveal any additional significant difference between groups. This study is the first to date to evaluate anatomy and function of the somatosensory cortex in a well-characterized sample of euthymic bipolar disorder females. Anatomical and functional changes in the somatosensory cortex in this population might contribute to the pathophysiology of bipolar disorder.

  7. Technical Assistance to Developers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rockward, Tommy; Borup, Rodney L.; Garzon, Fernando H.

    2012-07-17

    This task supports the allowance of technical assistance to fuel-cell component and system developers as directed by the DOE. This task includes testing of novel materials and participation in the further development and validation of single cell test protocols. This task also covers technical assistance to DOE Working Groups, the U.S. Council for Automotive Research (USCAR) and the USCAR/DOE Driving Research and Innovation for Vehicle efficiency and Energy sustainability (U.S. Drive) Fuel Cell Technology Team. Assistance includes technical validation of new fuel cell materials and methods, single cell fuel cell testing to support the development of targets and test protocols,more » and regular advisory participation in other working groups and reviews. This assistance is made available to PEM fuel cell developers by request and DOE Approval. The objectives are to: (1) Support technically, as directed by DOE, fuel cell component and system developers; (2) Assess fuel cell materials and components and give feedback to developers; (3) Assist the DOE Durability Working Group with the development of various new material durability Testing protocols; and (4) Provide support to the U.S. Council for Automotive Research (USCAR) and the USCAR/DOE Fuel Cell Technology Team. FY2012 specific technical objectives are: (1) Evaluate novel MPL materials; (2) Develop of startup/ shutdown protocol; (3) Test the impact of hydrophobic treatment on graphite bi-polar plates; (4) Perform complete diagnostics on metal bi-polar plates for corrosion; and (5) Participate and lead efforts in the DOE Working Groups.« less

  8. Unified planar process for fabricating heterojunction bipolar transistors and buried-heterostructure lasers utilizing impurity-induced disordering

    NASA Astrophysics Data System (ADS)

    Thornton, R. L.; Mosby, W. J.; Chung, H. F.

    1988-12-01

    We describe results on a novel geometry of heterojunction bipolar transistor that has been realized by impurity-induced disordering. This structure is fabricated by a method that is compatible with techniques for the fabrication of low threshold current buried-heterostructure lasers. We have demonstrated this compatibility by fabricating a hybrid laser/transistor structure that operates as a laser with a threshold current of 6 mA at room temperature, and as a transistor with a current gain of 5.

  9. Component variations and their effects on bipolar nickel-hydrogen cell performance

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.; Gahn, Randall F.; Gonzalez-Sanabria, Olga D.; Cataldo, Robert L.; Gemeiner, Russel P.

    1987-01-01

    A 50 cell bipolar nickel-hydrogen battery was assembled to demonstrate the feasibility of constructing a high voltage stack of cells. Various component combinations were tested in this battery. The battery had approximately 1 ampere-hour of capacity and was constructed from components with an active area of 2 x 2 inches. The components were parametrically varied to give a comparison of nickel electrodes, hydrogen electrodes, separators, fill procedures and electrolyte reservoir plate thicknesses. Groups of five cells were constructed using the same components; ten combinations were tested in all. The battery was thoroughly characterized at various change and discharge rates as well as with various pulse patterns and rates. Over a period of 1400 40-percent DOD LEO cycles some of the groups began to exhibit performance differences. In general, only separator variations had a significant effect on cell performance. It also appears that shunt currents may have been operating within the stack, resulting in electrolyte transfer from one cell to another, thus contributing to cell performance variations.

  10. Component variations and their effects on bipolar nickel-hydrogen cell performance

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.; Gahn, Randall F.; Gonzalez-Sanabria, Olga D.; Cataldo, Robert L.; Gemeiner, Russel P.

    1987-01-01

    A 50 cell bipolar nickel-hydrogen battery was assembled to demonstrate the feasibility of constructing a high voltage stack of cells. Various component combinations were tested in this battery. The battery had approximately 1 ampere-hour of capacity and was constructed from components with an active area of 2" X 2". The components were parametrically varied to give a comparison of nickel electrodes, hydrogen electrodes, separators, fill procedures and electrolyte reservoir plate thicknesses. Groups of five cells were constructed using the same components; ten combinations were tested in all. The battery was thoroughly characterized at various change and discharge rates as well as with various pulse patterns and rates. Over a period of 1400 40% DOD LEO cycles some of the groups began to exhibit performance differences. In general, only separator variations had a significant effect on cell performance. It also appears that shunt currents may have been operating within the stack, resulting in electrolyte transfer from one cell to another, thus contributing to cell performance variations.

  11. The Transient Intermediate Plexiform Layer, a Plexiform Layer-like Structure Temporarily Existing in the Inner Nuclear Layer in Developing Rat Retina.

    PubMed

    Park, Hyung Wook; Kim, Hong-Lim; Park, Yong Soo; Kim, In-Beom

    2018-02-01

    The retina is a highly specialised part of the brain responsible for visual processing. It is well-laminated; three layers containing five different types of neurons are compartmentalised by two synaptic layers. Among the retinal layers, the inner nuclear layer (INL) is composed of horizontal, bipolar, and amacrine cell types. Bipolar cells form one sublayer in the distal half of the IPL, while amacrine cells form another sublayer in the proximal half, without any border-like structure. Here, we report that a plexiform layer-like structure exists temporarily in the border between the bipolar and amacrine sublayers in the INL in the rat retina during retinal development. This transient intermediate plexiform layer (TIPL) appeared at postnatal day (PD) 7 and then disappeared around PD 12. Most apoptotic cells in the INL were found near the TIPL. These results suggest that the TIPL may contribute to the formation of sublayers and the cell number limit in the INL.

  12. Temperament in the clinical differentiation of depressed bipolar and unipolar major depressive patients.

    PubMed

    Mendlowicz, Mauro V; Akiskal, Hagop S; Kelsoe, John R; Rapaport, Mark H; Jean-Louis, Girardin; Gillin, J Christian

    2005-02-01

    To examine differences in temperament profiles between patients with recurrent unipolar and bipolar depression. Depressed individuals with recurrent major depressive disorder (MDD) (n = 94) and those with bipolar (n = 59) disorders (about equally divided between types I and II) were recruited by newspaper advertisement, radio and television announcements, flyers and newsletters, and word of mouth. All patients were interviewed using the Structured Clinical Interview for DSM III-R (SCID) and had the severity of their depressive episode assessed by means of the 17-item Hamilton Rating Scale for Depression. All patients filled out the TEMPS-A, a validated instrument. Temperament differences between bipolar and MDD patients were examined using MANCOVA. Overall significant effect of the fixed factor (bipolar vs. unipolar) was noted for the temperament scores [Hotelling's F((5,142)) = 2.47, p < 0.05]. Overall effects were found for age [F((5,142)) = 2.40, p < 0.05], but not for gender and severity of depression [F((5,142)) = 1.65, p = 0.15 and F((5,142)) = 0.66, p = 0.66, respectively]. Dependent variables included the five subscales of the TEMPS-A, but only the cyclothymic temperament scores showed significant between-group differences. Small bipolar subsample cell sizes did not permit to test the specificity of the findings for bipolar II vs. bipolar I patients. The finding that the clyclothymic subscale is significantly elevated in the bipolar vs. the unipolar depressive group supports the theoretical assumptions upon which the scale is based, and suggests that it might become a useful tool for clinical and research purposes.

  13. Sustained unemployment in psychiatric outpatients with bipolar depression compared to major depressive disorder with comorbid borderline personality disorder.

    PubMed

    Zimmerman, Mark; Martinez, Jennifer H; Young, Diane; Chelminski, Iwona; Dalrymple, Kristy

    2012-12-01

    The morbidity associated with bipolar disorder is, in part, responsible for repeated calls for improved detection and recognition. No such clinical commentary exists for improved detection of borderline personality disorder in depressed patients. Clinical experience suggests that borderline personality disorder is as disabling as bipolar disorder; however, no studies have directly compared the two disorders. For this reason we undertook the current analysis from the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project comparing unemployment and disability rates in patients with bipolar disorder and borderline personality disorder. Patients were interviewed with semi-structured interviews. We compared three non-overlapping groups of depressed patients: (i) 181 patients with DSM-IV major depressive disorder and borderline personality disorder, (ii) 1068 patients with major depressive disorder without borderline personality disorder, and (iii) 84 patients with bipolar depression without borderline personality disorder. Compared to depressed patients without borderline personality disorder, depressed patients with borderline personality disorder were significantly more likely to have been persistently unemployed. A similar difference was found between patients with bipolar depression and major depressive disorder without borderline personality disorder. No differences were found between patients with bipolar depression and depression with borderline personality disorder. Both bipolar disorder and borderline personality disorder were associated with impaired occupational functioning and thus carry a significant public health burden. Efforts to improve detection of borderline personality disorder in depressed patients might be as important as the recognition of bipolar disorder. © 2012 John Wiley and Sons A/S.

  14. Iowa gambling task performance in euthymic bipolar I disorder: A meta-analysis and empirical study

    PubMed Central

    Edge, Michael D.; Johnson, Sheri L.; Ng, Tommy; Carver, Charles S.

    2013-01-01

    Background The Iowa Gambling Task (IGT) has been recommended as an index of reward sensitivity, which is elevated in bipolar disorder. We conducted a meta-analysis of IGT performance in euthymic bipolar I disorder compared with control participants. Findings indicated that people with bipolar disorder make more risky choices than control participants, though the effect is small (g=0.35). It is not clear which of the many processes involved in IGT performance are involved in producing the observed group difference. Methods Fifty-five euthymic people with bipolar disorder and 39 control participants completed the IGT. The Expectancy Valence Model was used to examine differences in IGT. We also examined whether variation in IGT performance within the bipolar group was related to current mood, illness course, impulsivity, or demographics. Results Bipolar and control groups did not differ on the total number of risky choices, rate of learning, or any of the parameters of the Expectancy Valence Model. IGT performance in bipolar disorder was not related to any of the examined individual differences. Limitations It is possible that there are group differences that are too small to detect at our sample size or that are not amenable to study via the Expectancy Valence Model. Conclusions We were unable to identify group differences on the IGT or correlates of IGT performance within bipolar disorder. Though the IGT may serve as a useful model for decision-making, its structure may make it unsuitable for behavioral assessment of reward sensitivity independent of punishment sensitivity. PMID:23219060

  15. Connectome Signatures of Neurocognitive Abnormalities in Euthymic Bipolar I Disorder

    PubMed Central

    Ajilore, Olusola; Vizueta, Nathalie; Walshaw, Patricia; Zhan, Liang; Leow, Alex; Altshuler, Lori L.

    2015-01-01

    Objectives Connectomics have allowed researchers to study integrative patterns of neural connectivity in humans. Yet, it is unclear how connectomics may elucidate structure-function relationships in bipolar I disorder (BPI). Expanding on our previous structural connectome study, here we used an overlapping sample with additional psychometric and fMRI data to relate structural connectome properties to both fMRI signals and cognitive performance. Methods 42 subjects completed a neuropsychological (NP) battery covering domains of processing speed, verbal memory, working memory, and cognitive flexibility. 32 subjects also had fMRI data performing a Go/NoGo task. Results Bipolar participants had lower NP performance across all domains, but only working memory reached statistical significance. In BPI participants, processing speed was significantly associated with both white matter integrity (WMI) in the corpus callosum and interhemispheric network integration. Mediation models further revealed that the relationship between interhemispheric integration and processing speed was mediated by WMI, and processing speed mediated the relationship between WMI and working memory. Bipolar subjects had significantly decreased BA47 activation during NoGo vs. Go. Significant predictors of BA47 fMRI activations during the Go/NoGo task were its nodal path length (left hemisphere) and its nodal clustering coefficient (right hemisphere). Conclusions This study suggests that structural connectome changes underlie abnormalities in fMRI activation and cognitive performance in euthymic BPI subjects. Results support that BA47 structural connectome changes may be a trait marker for BPI. Future studies are needed to determine if these “connectome signatures” may also confer a biological risk and/or serve as predictors of relapse. PMID:26228398

  16. BrainAGE score indicates accelerated brain aging in schizophrenia, but not bipolar disorder.

    PubMed

    Nenadić, Igor; Dietzek, Maren; Langbein, Kerstin; Sauer, Heinrich; Gaser, Christian

    2017-08-30

    BrainAGE (brain age gap estimation) is a novel morphometric parameter providing a univariate score derived from multivariate voxel-wise analyses. It uses a machine learning approach and can be used to analyse deviation from physiological developmental or aging-related trajectories. Using structural MRI data and BrainAGE quantification of acceleration or deceleration of in individual aging, we analysed data from 45 schizophrenia patients, 22 bipolar I disorder patients (mostly with previous psychotic symptoms / episodes), and 70 healthy controls. We found significantly higher BrainAGE scores in schizophrenia, but not bipolar disorder patients. Our findings indicate significantly accelerated brain structural aging in schizophrenia. This suggests, that despite the conceptualisation of schizophrenia as a neurodevelopmental disorder, there might be an additional progressive pathogenic component. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  17. High-frequency output characteristics of AlGaAs/GaAs heterojunction bipolar transistors for large-signal applications

    NASA Astrophysics Data System (ADS)

    Chen, J.; Gao, G. B.; Ünlü, M. S.; Morkoç, H.

    1991-11-01

    High-frequency ic- vce output characteristics of bipolar transistors, derived from calculated device cutoff frequencies, are reported. The generation of high-frequency output characteristics from device design specifications represents a novel bridge between microwave circuit design and device design: the microwave performance of simulated device structures can be analyzed, or tailored transistor device structures can be designed to fit specific circuit applications. The details of our compact transistor model are presented, highlighting the high-current base-widening (Kirk) effect. The derivation of the output characteristics from the modeled cutoff frequencies are then presented, and the computed characteristics of an AlGaAs/GaAs heterojunction bipolar transistor operating at 10 GHz are analyzed. Applying the derived output characteristics to microwave circuit design, we examine large-signal class A and class B amplification.

  18. Measuring pathology using the PANSS across diagnoses: Inconsistency of the positive symptom domain across schizophrenia, schizoaffective, and bipolar disorder.

    PubMed

    Anderson, Ariana E; Mansolf, Maxwell; Reise, Steven P; Savitz, Adam; Salvadore, Giacomo; Li, Qingqin; Bilder, Robert M

    2017-12-01

    Although the Positive and Negative Syndrome Scale (PANSS) was developed for use in schizophrenia (SZ), antipsychotic drug trials use the PANSS to measure symptom change also for bipolar (BP) and schizoaffective (SA) disorder, extending beyond its original indications. If the dimensions measured by the PANSS are different across diagnoses, then the same score change for the same drug condition may have different meanings depending on which group is being studied. Here, we evaluated whether the factor structure in the PANSS was consistent across schizophrenia (n = 3647), bipolar disorder (n = 858), and schizoaffective disorder (n = 592). Along with congruency coefficients, Hancock's H, and Jaccard indices, we used target rotations and statistical tests of invariance based on confirmatory factor models. We found the five symptom dimensions measured by the 30-item PANSS did not generalize well to schizoaffective and bipolar disorders. A model based on an 18-item version of the PANSS generalized better across SZ and BP groups, but significant problems remained in generalizing some of the factors to the SA sample. Schizophrenia and bipolar disorder showed greater similarity in factor structure than did schizophrenia and schizoaffective disorder. The Anxiety/Depression factor was the most consistent across disorders, while the Positive factor was the least consistent. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The Expanding Bipolar Conic Shell of the Symbiotic Star AG Peg

    NASA Astrophysics Data System (ADS)

    Lee, Seong-Jae; Hyung, Siek

    2018-06-01

    Symbiotic stars are the most interesting since some systems are believed to host the most massive white dwarf, like SN Ia progenitors. Most recently, Lee and Hyung (2018, LH18) proposed a bipolar conic shell structure for the observed high expansion Hα and Hβ line profiles and other double peak lines observed in 1998 September (phase φ = 10.24): the physical conditions for the white dwarf luminosity and the ionized HII zone, responsible for double Gaussian optical lines including Balmer and Lyman line fluxes, were taken from the P-I model with gas density, nH = 109.85 cm-3 , while the column density for the scattering neutral zone was derived from the broader line components based on the result by Monte Carlo simulations. In this investigation, we examined whether the expanding shells of the bipolar conical geometry as proposed by LH18 would be able to form the other Hα and Hβ line profiles observed in other phases, φ = 11.56 and 11.98 (in 2001 August and 2002 August). We look into the kinematical property of the bipolar conic shell structure responsible for the HII and HI zones and then we discuss the secular variation of the broad line feature and the origin of the bipolar cone, i.e., part of a common envelope formed through the mass inflows from the giant star.

  20. Relationship between structural abnormalities in the cerebellum and dementia, posttraumatic stress disorder and bipolar disorder.

    PubMed

    Baldaçara, Leonardo; Borgio, João Guilherme Fiorani; Araújo, Célia; Nery-Fernandes, Fabiana; Lacerda, Acioly Luiz Taveres; Moraes, Walter André Dos Santos; Montaño, Maria Beatriz Marcondes Macedo; Rocha, Marlos; Quarantini, Lucas C; Schoedl, Aline; Pupo, Mariana; Mello, Marcelo F; Andreoli, Sergio B; Miranda-Scippa, Angela; Ramos, Luiz Roberto; Mari, Jair J; Bressan, Rodrigo Affonseca; Jackowski, Andrea Parolin

    2012-01-01

    New evidence suggests that the cerebellum has structural and functional abnormalities in psychiatric disorders. In this research, the goal was to measure the volume of the cerebellum and its subregions in individuals with psychiatric disorders and to relate these findings to their symptoms. Patients with different degrees of cognitive impairment (Epidemiology of the Elderly - UNIFESP) and patients with post-traumatic stress disorder (PTSD) from population studies were analyzed. Also, patients with bipolar disorder from an outpatient clinic (Center for the Study of Mood and Anxiety Disorders, Universidade Federal da Bahia) were recruited for this study. All subjects underwent a 1.5T structural magnetic resonance scan. Volumetric measures and symptom measurements, by psychometric scales, were performed and compared between patients and controls. The cerebellum volume was reduced in patients with cognitive impairment without dementia and with dementia, in patients with PTSD, and in patients with bipolar disorder compared to controls. In dementia and PTSD, the left cerebellar hemisphere and vermis volume were reduced. In bipolar disorder, volumes of both hemispheres and the vermis were reduced. In the first two studies, these cerebellar volumetric reductions correlated with symptoms of the disease. The exact nature of cerebellar involvement in mental processes is still not fully understood. However, abnormalities in cerebellar structure and its functions have been reported in some of these diseases. Future studies with larger samples are needed to clarify these findings and investigate whether they are important for treatment and prognosis.

  1. Differential impairment of social cognition factors in bipolar disorder with and without psychotic features and schizophrenia.

    PubMed

    Thaler, Nicholas S; Allen, Daniel N; Sutton, Griffin P; Vertinski, Mary; Ringdahl, Erik N

    2013-12-01

    While it is well-established that patients with schizophrenia and bipolar disorder exhibit deficits in social cognition, few studies have separately examined bipolar disorder with and without psychotic features. The current study addressed this gap by comparing patients with bipolar disorder with (BD+) and without (BD-) psychotic features, patients with schizophrenia (SZ), and healthy controls (NC) across social cognitive measures. Principal factor analysis on five social cognition tasks extracted a two-factor structure comprised of social/emotional processing and theory of mind. Factor scores were compared among the four groups. Results identified differential patterns of impairment between the BD+ and BD- group on the social/emotional processing factor while all clinical groups performed poorer than controls on the theory of mind factor. This provides evidence that a history of psychosis should be taken into account while evaluating social cognition in patients with bipolar disorder and also raises hypotheses about the relationship between social cognition and psychosis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Preparation and characterization of mono-sheet bipolar membranes by pre-irradiation grafting method for fuel cell applications

    NASA Astrophysics Data System (ADS)

    Guan, Yingjie; Fang, Jun; Fu, Tao; Zhou, Huili; Wang, Xin; Deng, Zixiang; Zhao, Jinbao

    2016-09-01

    A new method for the preparation of the mono-sheet bipolar membrane applied to fuel cells was developed based on the pre-irradiation grafting technology. A series of bipolar membranes were successfully prepared by simultaneously grafting of styrene onto one side of the poly(ethylene-co-tetrafluoroethylene) base film and 1-vinylimidazole onto the opposite side, followed by the sulfonation and alkylation, respectively. The chemical structures and microstructures of the prepared membranes were investigated by ATR-FTIR and SEM-EDS. The TGA measurements demonstrated the prepared bipolar membranes have reasonable thermal stability. The ion exchange capacity, water uptake and ionic conductivity of the membranes were also characterized. The H2/O2 single fuel cells using these membranes were evaluated and revealed a maximum power density of 107 mW cm-2 at 35 °C with unhumidified hydrogen and oxygen. The preliminary performances suggested the great prospect of these membranes in application of bipolar membrane fuel cells.

  3. Extreme Appraisals of Internal States and Bipolar Symptoms: The Hypomanic Attitudes and Positive Predictions Inventory

    ERIC Educational Resources Information Center

    Dodd, Alyson L.; Mansell, Warren; Morrison, Anthony P.; Tai, Sara

    2011-01-01

    The Hypomanic Attitudes and Positive Predictions Inventory (HAPPI; W. Mansell, 2006) was developed to assess multiple, extreme, self-relevant appraisals of internal states. The present study aimed to validate the HAPPI in a clinical sample. Participants (N = 50) with a diagnosis of bipolar disorder (confirmed by a structured clinical interview)…

  4. Performance of the rebuilt SUERC single-stage accelerator mass spectrometer

    NASA Astrophysics Data System (ADS)

    Shanks, Richard P.; Ascough, Philippa L.; Dougans, Andrew; Gallacher, Paul; Gulliver, Pauline; Rood, Dylan H.; Xu, Sheng; Freeman, Stewart P. H. T.

    2015-10-01

    The SUERC bipolar single-stage accelerator mass spectrometer (SSAMS) has been dismantled and rebuilt to accommodate an additional rotatable pre-accelerator electrostatic spherical analyser (ESA) and a second ion source injector. This is for the attachment of an experimental positive-ion electron cyclotron resonance (ECR) ion source in addition to a Cs-sputter source. The ESA significantly suppresses oxygen interference to radiocarbon detection, and remaining measurement interference is now thought to be from 13C injected as 13CH molecule scattering off the plates of a second original pre-detector ESA.

  5. Development and test fuel cell powered on-site integrated total energy systems. Phase 3: Full-scale power plant development

    NASA Technical Reports Server (NTRS)

    Kaufman, A.

    1982-01-01

    The on-site system application analysis is summarized. Preparations were completed for the first test of a full-sized single cell. Emphasis of the methanol fuel processor development program shifted toward the use of commercial shell-and-tube heat exchangers. An improved method for predicting the carbon-monoxide tolerance of anode catalysts is described. Other stack support areas reported include improved ABA bipolar plate bonding technology, improved electrical measurement techniques for specification-testing of stack components, and anodic corrosion behavior of carbon materials.

  6. Psychosocial morbidity associated with bipolar disorder and borderline personality disorder in psychiatric out-patients: comparative study.

    PubMed

    Zimmerman, Mark; Ellison, William; Morgan, Theresa A; Young, Diane; Chelminski, Iwona; Dalrymple, Kristy

    2015-10-01

    The morbidity associated with bipolar disorder is, in part, responsible for repeated calls for improved detection and recognition. No such commentary exists for the improved detection of borderline personality disorder. Clinical experience suggests that it is as disabling as bipolar disorder, but no study has directly compared the two disorders. To compare the levels of psychosocial morbidity in patients with bipolar disorder and borderline personality disorder. Patients were assessed with semi-structured interviews. We compared 307 patients with DSM-IV borderline personality disorder but without bipolar disorder and 236 patients with bipolar disorder but without borderline personality disorder. The patients with borderline personality disorder less frequently were college graduates, were diagnosed with more comorbid disorders, more frequently had a history of substance use disorder, reported more suicidal ideation at the time of the evaluation, more frequently had attempted suicide, reported poorer social functioning and were rated lower on the Global Assessment of Functioning. There was no difference between the two patient groups in history of admission to psychiatric hospital or time missed from work during the past 5 years. The level of psychosocial morbidity associated with borderline personality disorder was as great as (or greater than) that experienced by patients with bipolar disorder. From a public health perspective, efforts to improve the detection and treatment of borderline personality disorder might be as important as efforts to improve the recognition and treatment of bipolar disorder. © The Royal College of Psychiatrists 2015.

  7. The characteristics of sleep in patients with manifest bipolar disorder, subjects at high risk of developing the disease and healthy controls.

    PubMed

    Ritter, Philipp S; Marx, Carolin; Lewtschenko, Natalia; Pfeiffer, Steffi; Leopold, Karolina; Bauer, Michael; Pfennig, Andrea

    2012-10-01

    Sleep is highly altered during affective episodes in patients with bipolar disorder. There is accumulating evidence that sleep is also altered in euthymic states. A deficit in sleep regulation may be a vulnerability factor with aetiological relevance in the development of the disease. This study aims to explore the objective, subjective and lifetime sleep characteristics of patients with manifest bipolar disorder and persons with an elevated risk of developing the disease. Twenty-two patients with bipolar I and II disorder, nine persons with an elevated risk of developing the disorder and 28 healthy controls were evaluated with a structured interview to characterize subjective and lifetime sleeping habits. In addition, participants wore an actimeter for six nights. Patients with bipolar disorder had longer sleep latency and duration compared with healthy controls as determined by actigraphy. The subjective and lifetime sleep characteristics of bipolar patients differed significantly from healthy controls. The results of participants with an elevated risk of developing the disorder had subjective and lifetime characteristics that were largely analogous to those of patients with manifest bipolar disorder. In particular, both groups described recurring insomnia and hypersomnia, sensitivity to shifts in circadian rhythm, difficulties awakening and prolonged sleep latency. This study provides further evidence that sleep and circadian timing are profoundly altered in patients with bipolar disorder. It may also tentatively suggest that sleep may be altered prior to the first manic episode in subjects at high risk.

  8. Normal pituitary volumes in children and adolescents with bipolar disorder: a magnetic resonance imaging study.

    PubMed

    Chen, Hua Hsuan; Nicoletti, Mark; Sanches, Marsal; Hatch, John P; Sassi, Roberto B; Axelson, David; Brambilla, Paolo; Keshavan, Matcheri S; Ryan, Neal; Birmaher, Boris; Soares, Jair C

    2004-01-01

    The volume of the pituitary gland in adults with bipolar disorder has previously been reported to be smaller than that of healthy controls. Such abnormalities would be consistent with the HPA dysfunction reported in this illness. We conducted a study of children and adolescents with bipolar disorder to determine whether size abnormalities in the pituitary gland are already present early in illness course. Magnetic resonance imaging (MRI) morphometric analysis of the pituitary gland was carried out in 16 DSM-IV children and adolescents with bipolar disorder (mean age+/-sd=15.5+/-3.4 years) and 21 healthy controls (mean age+/-sd=16.9+/-3.8 years). Subjects underwent a 1.5 T MRI, with 3-D Spoiled Gradient Recalled (SPGR) acquisition. There was no statistically significant difference between pituitary gland volumes of bipolar patients compared to healthy controls (ANCOVA, age, gender, and ICV as covariates; F=1.77, df=1,32, P=.19). There was a statistically significant direct relationship between age and pituitary gland volume in both groups (r=.59, df=17, P=.007 for healthy controls; r=.61, df=12, P=.008 for bipolar patients). No evidence of size abnormalities in the pituitary gland was found in child and adolescent bipolar patients, contrary to reports involving adult bipolar patients. This suggests that anatomical abnormalities in this structure may develop later in illness course as a result of continued HPA dysfunction. (c) 2005 Wiley-Liss, Inc.

  9. The quality of severe mental disorder diagnoses in a national health registry as compared to research diagnoses based on structured interview.

    PubMed

    Nesvåg, Ragnar; Jönsson, Erik G; Bakken, Inger Johanne; Knudsen, Gun Peggy; Bjella, Thomas D; Reichborn-Kjennerud, Ted; Melle, Ingrid; Andreassen, Ole A

    2017-03-14

    Utilization of diagnostic information from national patient registries rests on the quality of the registered diagnoses. We aimed to investigate the agreement and consistency of diagnoses of psychotic and bipolar disorders in the Norwegian Patient Registry (NPR) compared to structured interview-based diagnoses given as part of a clinical research project. Diagnostic data from NPR were obtained for the period 01.01.2008-31.12.2013 for all patients who had been included in the Thematically Organized Psychosis (TOP) study between 18.10.2002 and 01.09.2014 with a Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) diagnosis of schizophrenia (n = 537), delusional disorder (n = 48), schizoaffective disorder (n = 118) or bipolar disorder (n = 408). Diagnostic agreement between the primary DSM-IV diagnosis in TOP and the International Classification of Diseases, 10th revision (ICD-10) diagnoses in NPR was evaluated using Cohen's unweighted nominal kappa (κ). Diagnostic consistency was calculated as the proportion of all registered severe mental disorder diagnoses in NPR that were equivalent to the primary diagnosis given in the TOP study. The proportion of patients registered with the equivalent ICD-10 diagnosis as the primary DSM-IV diagnosis given in TOP was 84.2% for the schizophrenia group, 68.8% for the delusional disorder group, 76.3% for the schizoaffective disorder group, and 78.4% for the bipolar disorder group. Diagnostic agreement was good for schizophrenia (κ = 0.74) and bipolar disorder (κ = 0.72), fair for schizoaffective disorder (κ = 0.63), and poor for delusional disorder (κ = 0.39). Among patients with DSM-IV schizophrenia, 4.7% were diagnosed with ICD-10 bipolar disorder, and among patients with DSM-IV bipolar disorder, 2.5% were diagnosed with ICD-10 schizophrenia. Diagnostic consistency was 84.9% for schizophrenia, 59.1% for delusional disorder, 65.9% for schizoaffective disorder, and 91.0% for bipolar disorder. When compared to research-based diagnoses, clinical diagnoses of schizophrenia and bipolar disorder in the NPR are accurate and consistent, with minimal diagnostic overlap between the two disorders.

  10. Self-esteem, social adjustment and suicidality in affective disorders.

    PubMed

    Daskalopoulou, E G; Dikeos, D G; Papadimitriou, G N; Souery, D; Blairy, S; Massat, I; Mendlewicz, J; Stefanis, C N

    2002-09-01

    Self-esteem (SE) and social adjustment (SA) are often impaired during the course of affective disorders; this impairment is associated with suicidal behaviour. The aim of the present study was to investigate SE and SA in unipolar or bipolar patients in relation to demographic and clinical characteristics, especially the presence of suicidality (ideation and/or attempt). Forty-four patients, 28 bipolar and 16 unipolar, in remission for at least 3 months, and 50 healthy individuals were examined through a structured clinical interview. SE and SA were assessed by the Rosenberg self-esteem scale and the social adjustment scale, respectively. The results have shown that bipolar patients did not differ from controls in terms of SE, while unipolar patients had lower SE than bipolars and controls. No significant differences in the mean SA scores were found between the three groups. Suicidality during depression was associated only in bipolar patients with lower SE at remission; similar but not as pronounced was the association of suicidality with SA. It is concluded that low SE lasting into remission seems to be related to the expression of suicidality during depressive episodes of bipolar patients, while no similar pattern is evident in unipolar patients.

  11. Absence of Auditory M100 Source Asymmetry in Schizophrenia and Bipolar Disorder: A MEG Study

    PubMed Central

    Wang, Ying; Feng, Yigang; Jia, Yanbin; Xie, Yanping; Wang, Wensheng; Guan, Yufang; Zhong, Shuming; Zhu, Dan; Huang, Li

    2013-01-01

    Background Whether schizophrenia and bipolar disorder are the clinical outcomes of discrete or shared causative processes is much debated in psychiatry. Several studies have demonstrated anomalous structural and functional superior temporal gyrus (STG) symmetries in schizophrenia. We examined bipolar patients to determine if they also have altered STG asymmetry. Methods Whole-head magnetoencephalography (MEG) recordings of auditory evoked fields were obtained for 20 subjects with schizophrenia, 20 with bipolar disorder, and 20 control subjects. Neural generators of the M100 auditory response were modeled using a single equivalent current dipole for each hemisphere. The source location of the M100 response was used as a measure of functional STG asymmetry. Results Control subjects showed the typical M100 asymmetrical pattern with more anterior sources in the right STG. In contrast, both schizophrenia and bipolar disorder patients displayed a symmetrical M100 source pattern. There was no significant difference in the M100 latency and strength in bilateral hemispheres within three groups. Conclusions Our results indicate that disturbed asymmetry of temporal lobe function may reflect a common deviance present in schizophrenia and bipolar disorder, suggesting the two disorders might share etiological and pathophysiological factors. PMID:24340052

  12. A comparative study of axis I antecedents before age 18 of unipolar depression, bipolar disorder and schizophrenia.

    PubMed

    Rubino, I Alex; Frank, Ellen; Croce Nanni, Roberta; Pozzi, Daniela; Lanza di Scalea, Teresa; Siracusano, Alberto

    2009-01-01

    Despite a large scientific literature on early clinical precursors of schizophrenia, bipolar disorder and unipolar depression, few data are available on axis I disorders preceding the adult onset of these illnesses. Disorders before the age of 18 years were retrospectively assessed with a structured interview in 3 groups of consecutive adult inpatients with DSM-IV diagnoses of schizophrenia (n = 197), major depressive disorder (n = 287) and bipolar disorder (n = 132). Only patients with adult onset of schizophrenia and of mania/hypomania were included. A sample of the general population served as control group (n = 300). The clinical groups significantly outnumbered the control sample on the majority of early axis I diagnoses. Schizophrenia was significantly associated (1) with attention deficit hyperactivity disorder (ADHD), ADHD inattentive subtype, ADHD hyperactive subtype and primary nocturnal enuresis, compared to unipolar depression, and (2) with social phobia and ADHD inattentive subtype, compared to bipolar disorder. Oppositional defiant disorder was significantly associated with bipolar disorder, compared to the other clinical and control groups. The ADHD hyperactive subtype predicted the adult onset of bipolar disorder compared to unipolar depression. Externalizing disorders seem of special importance as regards the clinical pathways toward schizophrenia.

  13. Similar familial underpinnings for full and subsyndromal pediatric bipolar disorder: A familial risk analysis.

    PubMed

    Wozniak, Janet; Uchida, Mai; Faraone, Stephen V; Fitzgerald, Maura; Vaudreuil, Carrie; Carrellas, Nicholas; Davis, Jacqueline; Wolenski, Rebecca; Biederman, Joseph

    2017-05-01

    To examine the validity of subthreshold pediatric bipolar I disorder (BP-I), we compared the familial risk for BP-I in the child probands who had either full BP-I, subthreshold BP-I, ADHD, or were controls that neither had ADHD nor bipolar disorder. BP-I probands were youth aged 6-17 years meeting criteria for BP-I, full (N=239) or subthreshold (N=43), and also included were their first-degree relatives (N=687 and N=120, respectively). Comparators were youth with ADHD (N=162), controls without ADHD or bipolar disorder (N=136), and their first-degree relatives (N=511 and N=411, respectively). We randomly selected 162 non-bipolar ADHD probands and 136 non-bipolar, non-ADHD control probands of similar age and sex distribution to the BP-I probands from our case-control ADHD family studies. Psychiatric assessments were made by trained psychometricians using the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children Epidemiological Version (KSADS-E) and Structured Clinical Interview for DSM-IV (SCID) structured diagnostic interviews. We analyzed rates of bipolar disorder using multinomial logistic regression. Rates of full BP-I significantly differed between the four groups (χ 2 3 =32.72, P<.001): relatives of full BP-I probands and relatives of subthreshold BP-I probands had significantly higher rates of full BP-I than relatives of ADHD probands and relatives of control probands. Relatives of full BP-I, subthreshold BP-I, and ADHD probands also had significantly higher rates of major depressive disorder compared to relatives of control probands. Our results showed that youth with subthreshold BP-I had similarly elevated risk for BP-I and major depressive disorder in first-degree relatives as youth with full BP-I. These findings support the diagnostic continuity between subsyndromal and fully syndromatic states of pediatric BP-I disorder. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Flexible bipolar nanofibrous membranes for improving gradient microstructure in tendon-to-bone healing.

    PubMed

    Li, Xiaoxi; Cheng, Ruoyu; Sun, Zhiyong; Su, Wei; Pan, Guoqing; Zhao, Song; Zhao, Jinzhong; Cui, Wenguo

    2017-10-01

    Enthesis is a specialized tissue interface between the tendon and bone. Enthesis structure is very complex because of gradient changes in its composition and structure. There is currently no strategy to create a suitable environment and to regenerate the gradual-changing enthesis because of the modular complexities between two tissue types. Herein, a dual-layer organic/inorganic flexible bipolar fibrous membrane (BFM) was successfully fabricated by electrospinning to generate biomimetic non-mineralized fibrocartilage and mineralized fibrocartilage in tendon-to-bone integration of enthesis. The growth of the in situ apatite nanoparticle layer was induced on the nano hydroxyapatite-poly-l-lactic acid (nHA-PLLA) fibrous layer in simulated body solution, and the poly-l-lactic acid (PLLA) fibrous layer retained its original properties to induce tendon regeneration. The in vivo results showed that BFM significantly increased the area of glycosaminoglycan staining at the tendon-bone interface and improved collagen organization when compared to the simplex fibrous membrane (SFM) of PLLA. Implanting the bipolar membrane also induced bone formation and fibrillogenesis as assessed by micro-CT and histological analysis. Biomechanical testing showed that the BFM group had a greater ultimate load-to-failure and stiffness than the SFM group at 12weeks after surgery. Therefore, this flexible bipolar nanofibrous membrane improves the healing and regeneration process of the enthesis in rotator cuff repair. In this study, we generated a biomimetic dual-layer organic/inorganic flexible bipolar fibrous membrane by sequential electrospinning and in situ biomineralization, producing integrated bipolar fibrous membranes of PLLA fibrous membrane as the upper layer and nHA-PLLA fibrous membrane as the lower layer to mimic non-mineralized fibrocartilage and mineralized fibrocartilage in tendon-to-bone integration of enthesis. Flexible bipolar nanofibrous membranes could be easily fabricated with gradient microstructure for enthesis regeneration in rotator cuff tears. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Highly uniform and reliable resistive switching characteristics of a Ni/WOx/p+-Si memory device

    NASA Astrophysics Data System (ADS)

    Kim, Tae-Hyeon; Kim, Sungjun; Kim, Hyungjin; Kim, Min-Hwi; Bang, Suhyun; Cho, Seongjae; Park, Byung-Gook

    2018-02-01

    In this paper, we investigate the resistive switching behavior of a bipolar resistive random-access memory (RRAM) in a Ni/WOx/p+-Si RRAM with CMOS compatibility. Highly unifrom and reliable bipolar resistive switching characteristics are observed by a DC voltage sweeping and its switching mechanism can be explained by SCLC model. As a result, the possibility of metal-insulator-silicon (MIS) structural WOx-based RRAM's application to Si-based 1D (diode)-1R (RRAM) or 1T (transistor)-1R (RRAM) structure is demonstrated.

  16. Effects of electrical conductivity of substrate materials on microstructure of diamond-like carbon films prepared by bipolar-type plasma based ion implantation

    NASA Astrophysics Data System (ADS)

    Nakao, S.; Sonoda, T.

    2013-03-01

    Diamond-like carbon (DLC) films are prepared by a bipolar-type plasma based ion implantation, and the structural differences between DLC films deposited on different electrical conductive substrates, i.e., conductive Si wafers and insulating glass plates are examined by Raman spectroscopy and x-ray photo emission spectroscopy (XPS). In the Raman measurements, graphite (G) and disorder (D) peaks are observed for both samples. However, the additional photo luminescence is overlapped on the spectra in the case of on-glass sample. To elucidate the structural difference, the intensity ratio of D to G peak (I(D)/I(G)), G peak position and full width at half maximum (FWHM) are obtained by curve fitting using Gaussian function and linear baseline. It is found that the I(D)/I(G) is lower, G peak position is higher and FWHM of G peak is narrower for on-glass sample than for on-Si sample. According to Robertson [1], lower I(D)/I(G) seems more sp3 C-C bonding in amount for on-glass sample. In contrast, higher G peak position and narrower FWHM of G peak suggest less sp3 C-C bonding in amount for on-glass sample. The results of XPS analysis with C1s spectra reveal that sp3 ratio, i.e., the intensity ratio of sp3/(sp3+sp2) is smaller for on-glass sample than for on-Si sample. The inconsistency of the trend between I(D)/I(G) and other parameters (G peak position and FWHM of G peak) might be caused by the overlap of photo luminescence signal on Raman spectrum as to on-glass sample. From these results, it is considered that sp3 C-C bonding is reduced in amount when using insulating substrate in comparison with conductive substrate.

  17. Screening the risk of bipolar spectrum disorders: Validity evidence of the Mood Disorder Questionnaire in adolescents and young adults.

    PubMed

    Fonseca-Pedrero, Eduardo; Ortuño-Sierra, Javier; Paino, Mercedes; Muñiz, José

    2016-01-01

    The aim of this study was to gather sources of validity evidence of the Mood Disorder Questionnaire (MDQ) in young adults for its use as a screening tool for bipolar spectrum disorders. The sample was composed of 1,002 participants, 268 men (26.7%). The mean age of participants was 21.1 years (SD=3.9). The results showed that between 3 and 59% of the sample reported some hypomanic experience. Gender differences were found in the total score of the MDQ. The analysis of the internal structure by exploratory factor analysis yielded 2 factors, called Energy-Activity and Disinhibition-Attention. This dimensional structure was replicated in the exploratory structural equation modeling (ESEM), and also had factorial equivalence by gender. Participants who met the cut-off points of the MDQ reported a worse perceived mental health status and more consummatory and anticipatory pleasure, compared to the low scores group. These findings indicate that the MDQ has adequate psychometric properties in non-clinical samples, and could be useful as a screening tool in psychopathology, with the possibility of optimizing strategies for early identification and prevention in individuals at high risk for bipolar disorders. Future studies should further explore the role of subclinical bipolar phenotype and conduct longitudinal studies in samples of the general population. Copyright © 2015 SEP y SEPB. Published by Elsevier España. All rights reserved.

  18. Bipolar radiofrequency ablation of spinal tumors: predictability, safety and outcome.

    PubMed

    Gazis, Angelos N; Beuing, Oliver; Franke, Jörg; Jöllenbeck, Boris; Skalej, Martin

    2014-04-01

    Bone metastases are often the cause of tumor-associated pain and reduction of quality of life. For patients that cannot be treated by surgery, a local minimally invasive therapy such as radiofrequency ablation can be a useful option. In cases in which tumorous masses are adjacent to vulnerable structures, the monopolar radiofrequency can cause severe neuronal damage because of the unpredictability of current flow. The aim of this study is to show that the bipolar radiofrequency ablation provides an opportunity to safely treat such spinal lesions because of precise predictability of the emerging ablation zone. Prospective cohort study of 36 patients undergoing treatment at a single institution. Thirty-six patients in advanced tumor stage with primary or secondary tumor involvement of spine undergoing radiofrequency ablation. Prediction of emerging ablation zone. Clinical outcome of treated patients. X-ray-controlled treatment of 39 lesions by bipolar radiofrequency ablation. Magnetic resonance imaging was performed pre- and postinterventionally. Patients were observed clinically during their postinterventional stay. The extent of the ablation zones was predictable to the millimeter because it did not cross the peri-interventional planned dorsal and ventral boundaries in any case. No complications were observed. Ablation of tumorous masses adjacent to vulnerable structures is feasible and predictable by using the bipolar radiofrequency ablation. Damage of neuronal structures can be avoided through precise prediction of the ablation area. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Factors associated with false positives in MDQ screening for bipolar disorder: Insight into the construct validity of the scale.

    PubMed

    Paterniti, Sabrina; Bisserbe, Jean-Claude

    2018-05-29

    Identifying bipolar patients in the first phases of the illness is essential to establish adequate treatment. The goal of this study was to examine the discriminant ability of the Mood Disorders Questionnaire (MDQ) in recognizing bipolar patients referred to a tertiary care structure. Between 2006 and 2012, we assessed 843 individuals referred to the Mood Disorders Program by family physicians in the community. The Structured Clinical Interview for DSM-IV-TR (SCID) was used to assess diagnoses. A nurse collected the information about lifetime symptoms of (hypo)mania in 759 individuals using the MDQ. Univariate chi-square test and logistic regression were used for the statistical analysis. Overall, 86% of the sample had a current anxiety or depressive disorder. When compared to the diagnoses formulated through the SCID, the sensitivity of the MDQ was 75.0%, the specificity was 74%, the positive predictive value was 55%, and the negative predictive value was 88%. Among non-bipolar patients, current post-traumatic stress disorder, borderline personality disorder, current or early remission substance use disorder, and the history of childhood abuse were independently associated with false positive screening using the MDQ. Individuals with current substance use disorders were under-represented, whether or not the patients were aware of their diagnosis of bipolar disorder was not recorded, and the history of childhood abuse was collected based on an open interview. The self-rated measure of the symptoms listed by the MDQ seems to measure a dimension shared by both bipolar disorder and other conditions characterized by affective instability and impulsivity. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Predictors for switch from unipolar major depressive disorder to bipolar disorder type I or II: a 5-year prospective study.

    PubMed

    Holma, K Mikael; Melartin, Tarja K; Holma, Irina A K; Isometsä, Erkki T

    2008-08-01

    In this naturalistic study, we investigated the rate, time course, and predictors of a diagnostic switch from unipolar major depressive disorder (MDD) to bipolar disorder type I or II during a 5-year follow-up. The Vantaa Depression Study included at baseline 269 psychiatric outpatients (82.9%) and inpatients (17.1%) with DSM-IV MDD, diagnosed using structured and semi-structured interviews and followed up at 6 months, 18 months, and 5 years between February 1, 1997 and April 30, 2004. Information on 248 MDD patients (92.2%) was available for analyses of the risk of diagnostic switch. Cox proportional hazards models were used. Twenty-two subjects (8.9%) with previous unipolar MDD switched to bipolar disorder type II and 7 (2.8%) to type I. Median time for switch to bipolar type I was significantly shorter than to type II. In Cox proportional hazards analyses, severity of MDD (hazard ratio [HR] = 1.08, 95% CI = 1.00 to 1.15, p = .036), obsessive-compulsive disorder (OCD) (HR = 5.00, 95% CI = 2.04 to 12.5, p < .001), social phobia (HR = 2.33, 95% CI = 1.00 to 5.26, p = .050), and large number of cluster B personality disorder symptoms (HR = 1.10, 95% CI = 1.02 to 1.20, p = .022) predicted switch. Among outpatients with MDD in secondary level psychiatric settings, diagnostic switch to bipolar disorder usually refers to type II rather than type I. The few switching to bipolar type I do so relatively early. Predictors for diagnostic switch include not only features of mood disorder, such as severity, but may also include some features of psychiatric comorbidity, such as concurrent social phobia, OCD, and symptoms of cluster B personality disorders.

  1. Diffusion Entropy: A Potential Neuroimaging Biomarker of Bipolar Disorder in the Temporal Pole.

    PubMed

    Spuhler, Karl; Bartlett, Elizabeth; Ding, Jie; DeLorenzo, Christine; Parsey, Ramin; Huang, Chuan

    2018-02-01

    Despite much research, bipolar depression remains poorly understood, with no clinically useful biomarkers for its diagnosis. The paralimbic system has become a target for biomarker research, with paralimbic structural connectivity commonly reported to distinguish bipolar patients from controls in tractography-based diffusion MRI studies, despite inconsistent findings in voxel-based studies. The purpose of this analysis was to validate existing findings with traditional diffusion MRI metrics and investigate the utility of a novel diffusion MRI metric, entropy of diffusion, in the search for bipolar depression biomarkers. We performed group-level analysis on 9 un-medicated (6 medication-naïve; 3 medication-free for at least 33 days) bipolar patients in a major depressive episode and 9 matched healthy controls to compare: (1) average mean diffusivity (MD) and fractional anisotropy (FA) and; (2) MD and FA histogram entropy-a statistical measure of distribution homogeneity-in the amygdala, hippocampus, orbitofrontal cortex and temporal pole. We also conducted classification analyses with leave-one-out and separate testing dataset (N = 11) approaches. We did not observe statistically significant differences in average MD or FA between the groups in any region. However, in the temporal pole, we observed significantly lower MD entropy in bipolar patients; this finding suggests a regional difference in MD distributions in the absence of an average difference. This metric allowed us to accurately characterize bipolar patients from controls in leave-one-out (accuracy = 83%) and prediction (accuracy = 73%) analyses. This novel application of diffusion MRI yielded not only an interesting separation between bipolar patients and healthy controls, but also accurately classified bipolar patients from controls. © 2017 Wiley Periodicals, Inc.

  2. Development of a bipolar disorder biobank: differential phenotyping for subsequent biomarker analyses.

    PubMed

    Frye, Mark A; McElroy, Susan L; Fuentes, Manuel; Sutor, Bruce; Schak, Kathryn M; Galardy, Christine W; Palmer, Brian A; Prieto, Miguel L; Kung, Simon; Sola, Christopher L; Ryu, Euijung; Veldic, Marin; Geske, Jennifer; Cuellar-Barboza, Alfredo; Seymour, Lisa R; Mori, Nicole; Crowe, Scott; Rummans, Teresa A; Biernacka, Joanna M

    2015-12-01

    We aimed to establish a bipolar disorder biobank to serve as a resource for clinical and biomarker studies of disease risk and treatment response. Here, we describe the aims, design, infrastructure, and research uses of the biobank, along with demographics and clinical features of the first participants enrolled. Patients were recruited for the Mayo Clinic Bipolar Biobank beginning in July 2009. The Structured Clinical Interview for DSM-IV was used to confirm bipolar diagnosis. The Bipolar Biobank Clinical Questionnaire and Participant Questionnaire were designed to collect detailed demographic and clinical data, including clinical course of illness measures that would delineate differential phenotypes for subsequent analyses. Blood specimens were obtained from participants, and various aliquots were stored for future research. As of September 2014, 1363 participants have been enrolled in the bipolar biobank. Among these first participants, 69.0 % had a diagnosis of bipolar disorder type I. The group was 60.2 % women and predominantly white (90.6 %), with a mean (SD) age of 42.6 (14.9) years. Clinical phenotypes of the group included history of psychosis (42.3 %), suicide attempt (32.5 %), addiction to alcohol (39.1 %), addiction to nicotine (39.8 %), obesity (42.9 %), antidepressant-induced mania (31.7 %), tardive dyskinesia (3.2 %), and history of drug-related serious rash (5.7 %). Quantifying phenotypic patterns of illness beyond bipolar subtype can provide more detailed clinical disease characteristics for biomarker research, including genomic-risk studies. Future research can harness clinically useful biomarkers using state-of-the-art research technology to help stage disease burden and better individualize treatment selection for patients with bipolar disorder.

  3. Novel multi-source phase-controlled radiofrequency technology for non-ablative and micro-ablative treatment of wrinkles, lax skin and acne scars.

    PubMed

    Elman, Monica; Harth, Yoram

    2011-01-01

    The basic properties of lasers and pulsed light sources limit their ability to deliver high energy to the dermis and subcutaneous tissues without excessive damage to the epidermis. Radiofrequency was shown to penetrate deeper than optical light sources independent of skin color. The early RF-based devices used single source bipolar RF, which is safe but limited in use due to the superficial flow of energy between the two bipolar electrodes. Another type of single source RF employs a single electrode (monopolar) in which the RF energy flows from one electrode on the surface of the skin through the entire body to a plate under the body. Although more effective than bipolar, this devices require intense active cooling of the skin and may be associated with considerable pain and other systemic and local safety concerns. Latest generation of RF technology developed by EndyMed Medical Ltd. (Caesarea, Israel) utilizes simultaneously six or more phase controlled RF generators (3DEEP technology). The multiple electrical fields created by the multiple sources "repel" or "attract" each other, leading to the precise 3 dimensional delivery of RF energy to the dermal and sub-dermal targets minimizing the energy flow through the epidermis without the need for active cooling. Confocal microscopy of the skin has shown that 6 treatment sessions of Multisource RF technology improve skin structure features. The skin after treatment had longer and narrower dermal papilla and denser and finer collagen fiber typical to younger skin as compared to pre treatment skin. Ultrasound of the skin showed after 6 treatment sessions reduction of 10 percent in the thickness of the subcutaneous fat layer. Non ablative facial clinical studies showed a significant reduction of wrinkles after treatment further reduced at 3 months follow-up. Body treatment studies showed a circumference reduction of 2.9 cm immediately after 6 treatments, and 2 cm at 12 months after the end of treatment, proving long term collagen remodeling effect. Clinical studies of the multisource fractional RF application have shown significant effects on wrinkles reduction and deep atrophic acne scars after 1-3 treatment sessions.

  4. Novel multi-source phase-controlled radiofrequency technology for non-ablative and micro-ablative treatment of wrinkles, lax skin and acne scars

    PubMed Central

    Elman, Monica; Harth, Yoram

    2011-01-01

    The basic properties of lasers and pulsed light sources limit their ability to deliver high energy to the dermis and subcutaneous tissues without excessive damage to the epidermis. Radiofrequency was shown to penetrate deeper than optical light sources independent of skin color. The early RF-based devices used single source bipolar RF, which is safe but limited in use due to the superficial flow of energy between the two bipolar electrodes. Another type of single source RF employs a single electrode (monopolar) in which the RF energy flows from one electrode on the surface of the skin through the entire body to a plate under the body. Although more effective than bipolar, this devices require intense active cooling of the skin and may be associated with considerable pain and other systemic and local safety concerns. Latest generation of RF technology developed by EndyMed Medical Ltd. (Caesarea, Israel) utilizes simultaneously six or more phase controlled RF generators (3DEEP technology). The multiple electrical fields created by the multiple sources “repel” or “attract” each other, leading to the precise 3 dimensional delivery of RF energy to the dermal and sub-dermal targets minimizing the energy flow through the epidermis without the need for active cooling. Confocal microscopy of the skin has shown that 6 treatment sessions of Multisource RF technology improve skin structure features. The skin after treatment had longer and narrower dermal papilla and denser and finer collagen fiber typical to younger skin as compared to pre treatment skin. Ultrasound of the skin showed after 6 treatment sessions reduction of 10 percent in the thickness of the subcutaneous fat layer. Non ablative facial clinical studies showed a significant reduction of wrinkles after treatment further reduced at 3 months follow-up. Body treatment studies showed a circumference reduction of 2.9 cm immediately after 6 treatments, and 2 cm at 12 months after the end of treatment, proving long term collagen remodeling effect. Clinical studies of the multisource fractional RF application have shown significant effects on wrinkles reduction and deep atrophic acne scars after 1–3 treatment sessions. PMID:24155523

  5. Techno-economic assessment of novel vanadium redox flow batteries with large-area cells

    NASA Astrophysics Data System (ADS)

    Minke, Christine; Kunz, Ulrich; Turek, Thomas

    2017-09-01

    The vanadium redox flow battery (VRFB) is a promising electrochemical storage system for stationary megawatt-class applications. The currently limited cell area determined by the bipolar plate (BPP) could be enlarged significantly with a novel extruded large-area plate. For the first time a techno-economic assessment of VRFB in a power range of 1 MW-20 MW and energy capacities of up to 160 MWh is presented on the basis of the production cost model of large-area BPP. The economic model is based on the configuration of a 250 kW stack and the overall system including stacks, power electronics, electrolyte and auxiliaries. Final results include a simple function for the calculation of system costs within the above described scope. In addition, the impact of cost reduction potentials for key components (membrane, electrode, BPP, vanadium electrolyte) on stack and system costs is quantified and validated.

  6. The functional neuroanatomy of bipolar disorder: a consensus model

    PubMed Central

    Strakowski, Stephen M; Adler, Caleb M; Almeida, Jorge; Altshuler, Lori L; Blumberg, Hilary P; Chang, Kiki D; DelBello, Melissa P; Frangou, Sophia; McIntosh, Andrew; Phillips, Mary L; Sussman, Jessika E; Townsend, Jennifer D

    2013-01-01

    Objectives Functional neuroimaging methods have proliferated in recent years, such that functional magnetic resonance imaging, in particular, is now widely used to study bipolar disorder. However, discrepant findings are common. A workgroup was organized by the Department of Psychiatry, University of Cincinnati (Cincinnati, OH, USA) to develop a consensus functional neuroanatomic model of bipolar I disorder based upon the participants’ work as well as that of others. Methods Representatives from several leading bipolar disorder neuroimaging groups were organized to present an overview of their areas of expertise as well as focused reviews of existing data. The workgroup then developed a consensus model of the functional neuroanatomy of bipolar disorder based upon these data. Results Among the participants, a general consensus emerged that bipolar I disorder arises from abnormalities in the structure and function of key emotional control networks in the human brain. Namely, disruption in early development (e.g., white matter connectivity, prefrontal pruning) within brain networks that modulate emotional behavior leads to decreased connectivity among ventral prefrontal networks and limbic brain regions, especially amygdala. This developmental failure to establish healthy ventral prefrontal–limbic modulation underlies the onset of mania and ultimately, with progressive changes throughout these networks over time and with affective episodes, a bipolar course of illness. Conclusions This model provides a potential substrate to guide future investigations and areas needing additional focus are identified. PMID:22631617

  7. Particle-in-cell simulations of asymmetric guide-field reconnection: quadrupolar structure of Hall magnetic field

    NASA Astrophysics Data System (ADS)

    Schmitz, R. G.; Alves, M. V.; Barbosa, M. V. G.

    2017-12-01

    One of the most important processes that occurs in Earth's magnetosphere is known as magnetic reconnection (MR). This process can be symmetric or asymmetric, depending basically on the plasma density and magnetic field in both sides of the current sheet. A good example of symmetric reconnection in terrestrial magnetosphere occurs in the magnetotail, where these quantities are similar on the north and south lobes. In the dayside magnetopause MR is asymmetric, since the plasma regimes and magnetic fields of magnetosheath and magnetosphere are quite different. Symmetric reconnection has some unique signatures. For example, the formation of a quadrupolar structure of Hall magnetic field and a bipolar Hall electric field that points to the center of the current sheet. The different particle motions in the presence of asymmetries change these signatures, causing the quadrupolar pattern to be distorted and forming a bipolar structure. Also, the bipolar Hall electric field is modified and gives rise to a single peak pointing toward the magnetosheat, considering an example of magnetopause reconnection. The presence of a guide-field can also distort the quadrupolar pattern, by giving a shear angle across the current sheet and altering the symmetric patterns, according to previous simulations and observations. Recently, a quadrupolar structure was observed in an asymmetric guide-field MR event using MMS (Magnetospheric Multiscale) mission data [Peng et al., JGR, 2017]. This event shows clearly that the density asymmetry and the guide-field were not sufficient to form signatures of asymmetric reconnection. Using the particle-in-cell code iPIC3D [Markidis et al, Mathematics and Computers in Simulation, 2010] with the MMS data from this event used to define input parameters, we found a quadrupolar structure of Hall magnetic field and a bipolar pattern of Hall electric field in ion scales, showing that our results are in an excellent agreement with the MMS observations. To our knowledge, this is the first time PIC simulations show this kind of results, since previous simulations have predicted bipolar pattern in the asymmetric guide-field reconnection.

  8. Deformation in Micro Roll Forming of Bipolar Plate

    NASA Astrophysics Data System (ADS)

    Zhang, P.; Pereira, M.; Rolfe, B.; Daniel, W.; Weiss, M.

    2017-09-01

    Micro roll forming is a new processing technology to produce bipolar plates for Proton Exchange Membrane Fuel Cells (PEMFC) from thin stainless steel foil. To gain a better understanding of the deformation of the material in this process, numerical studies are necessary before experimental implementation. In general, solid elements with several layers through the material thickness are required to analyse material thinning in processes where the deformation mode is that of bending combined with tension, but this results in high computational costs. This pure solid element approach is especially time-consuming when analysing roll forming processes which generally involves feeding a long strip through a number of successive roll stands. In an attempt to develop a more efficient modelling approach without sacrificing accuracy, two solutions are numerically analysed with ABAQUS/Explicit in this paper. In the first, a small patch of solid elements over the strip width and in the centre of the “pre-cut” sheet is coupled with shell elements while in the second approach pure shell elements are used to discretize the full sheet. In the first approach, the shell element enables accounting for the effect of material being held in the roll stands on material flow while solid elements can be applied to analyse material thinning in a small discrete area of the sheet. Experimental micro roll forming trials are performed to prove that the coupling of solid and shell elements can give acceptable model accuracy while using shell elements alone is shown to result in major deviations between numerical and experimental results.

  9. The double layers in the plasma sheet boundary layer during magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Guo, J.; Yu, B.

    2014-11-01

    We studied the evolutions of double layers which appear after the magnetic reconnection through two-dimensional electromagnetic particle-in-cell simulation. The simulation results show that the double layers are formed in the plasma sheet boundary layer after magnetic reconnection. At first, the double layers which have unipolar structures are formed. And then the double layers turn into bipolar structures, which will couple with another new weak bipolar structure. Thus a new double layer or tripolar structure comes into being. The double layers found in our work are about several ten Debye lengths, which accords with the observation results. It is suggested that the electron beam formed during the magnetic reconnection is responsible for the production of the double layers.

  10. The Reciprocal Relationship between Bipolar Disorder and Social Interaction: A Qualitative Investigation.

    PubMed

    Owen, Rebecca; Gooding, Patricia; Dempsey, Robert; Jones, Steven

    2017-07-01

    Evidence suggests that social support can influence relapse rates, functioning and various clinical outcomes in people with bipolar disorder. Yet 'social support' is a poorly defined construct, and the mechanisms by which it affects illness course in bipolar disorder remain largely unknown. Key aims of this study were to ascertain which facets of social interaction affect mood management in bipolar disorder, and how symptoms of bipolar disorder can influence the level of support received. Semi-structured qualitative interviews were conducted with 20 individuals with bipolar disorder. Questions were designed to elicit: the effects of social interaction upon the management and course of bipolar disorder; and the impact of bipolar disorder upon social relationships. An inductive thematic analysis was used to analyse the data. Empathy and understanding from another person can make it easier to cope with bipolar disorder. Social interaction can also provide opportunities to challenge negative ruminative thoughts and prevent the onset of a major mood episode. The loss of social support, particularly through bereavement, creates a loss of control and can trigger mania or depression. Hypomanic symptoms can facilitate new social connections, whereas disinhibited and risky behaviour exhibited during mania can cause the breakdown of vital relationships. An in-depth clinical formulation of an individual's perceptions of how their illness affects and is affected by social interaction is crucial to understanding psychosocial factors which influence mood management. These results have clear application in interventions which aim to promote improved wellbeing and social functioning in bipolar disorder. Copyright © 2016 John Wiley & Sons, Ltd. The relationship between bipolar-related experiences and social interaction is complex and multi-faceted. Bipolar disorder can damage social relationships and create a loss of social control via extreme mood states, but it can also offer a social advantage through elevated self-confidence during hypomania and enhanced resilience post-recovery. Positive social experiences can facilitate better personal coping and enhanced mood management, whilst negative social experiences can trigger the onset of acute mood episodes. A comprehensive formulation of the reciprocal links between facets of bipolar disorder and characteristics of interpersonal relationships should be used to guide psychosocial interventions that aim to enhance emotion regulation and improve functioning. Copyright © 2016 John Wiley & Sons, Ltd.

  11. Factor Structure of Cognition and Functional Capacity in Two Studies of Schizophrenia and Bipolar Disorder: Implications for Genomic Studies

    PubMed Central

    Harvey, Philip D.; Aslan, Mihaela; Du, Mengtian; Zhao, Hongyu; Siever, Larry J.; Pulver, Ann; Gaziano, J. Michael; Concato, John

    2015-01-01

    Objective Impairments in cognition and everyday functioning are common in schizophrenia and bipolar disorder. Based on two studies of schizophrenia (SCZ) and bipolar I disorder (BPI) with similar methods, this paper presents factor analyses of cognitive and functional capacity (FC) measures. The overall goal of these analyses was to determine whether performance-based assessments should be examined individually, or aggregated on the basis of the correlational structure of the tests and as well as to evaluate the similarity of factor structures in SCZ and BPI. Method Veterans Affairs (VA) Cooperative Studies Program study #572, evaluated cognitive and FC measures among 5,414 BPI and 3,942 SZ patients. A second study evaluated similar neuropsychological (NP) and FC measures among 368 BPI and 436 SZ patients. Principal components analysis, as well as exploratory and confirmatory factor analyses, were used to examine the data. Results Analyses in both datasets suggested that NP and FC measures were explained by of a single underlying factor in BPI and SCZ patients, both when analyzed separately or as in a combined sample. The factor structure in both studies was similar, with or without inclusion of FC measures; homogeneous loadings were observed for that single factor across cognitive and FC domains across the samples. Conclusions The empirically derived factor model suggests that NP performance and FC are best explained as a single latent trait applicable to people with schizophrenia and bipolar illness. This single measure may enhance the robustness of the analyses relating genomic data to performance-based phenotypes. PMID:26710094

  12. Neuroanatomical Characterization of Child Offspring of Bipolar Parents

    PubMed Central

    Singh, Manpreet K.; DelBello, Melissa P.; Adler, Caleb M.; Stanford, Kevin E.; Strakowski, Stephen M.

    2012-01-01

    Objectives To examine structural differences in selected anterior limbic brain regions between at-risk children of parents with bipolar I disorder and children with healthy parents. We hypothesized that at-risk children would exhibit abnormalities in brain regions that are involved in mood regulation. Methods Children (8–12 years old) of parents with bipolar I disorder (“at-risk”, AR, N=21) and of parents without any DSM-IV Axis I disorder (health controls, HC, N=24) were evaluated using diagnosticassessments and brain magnetic resonance imaging (MRI). Morphometric analyses were used to examine group differences in the prefrontal cortical, thalamic, striatal, and amygdalar volumes. Results Nine (43%) of the AR children met DSM-IV-TR criteria for a non-bipolar mood disorder at the time of assessment. AR and HC children did not demonstrate statistically significant differences across regions of interest [Wilks Lambda = 0.86, F(4,39)=1.64, p=0.18; effect size, (f)=0.19]. Post-hoc analyses of covariance showed the largest relative effect size was contributed by the prefrontal cortex [(f)=0.26]. Conclusions 8 to 12 year old children with a familial risk for mania do not exhibit any statistically significant volumetric differences in the prefrontal cortex, thalamus, striatum, or amygdala as compared to age matched children of parents without any psychopathology. Longitudinal studies examining whether structural changes over time may be associated with vulnerability for developing subsequent bipolar disorder are needed to clarify the underlying pathophysiology of this disorder. PMID:18356766

  13. Self-mutilation and suicide attempts: relationships to bipolar disorder, borderline personality disorder, temperament and character.

    PubMed

    Joyce, Peter R; Light, Katrina J; Rowe, Sarah L; Cloninger, C Robert; Kennedy, Martin A

    2010-03-01

    Self-mutilation has traditionally been associated with borderline personality disorder, and seldom examined separately from suicide attempts. Clinical experience suggests that self-mutilation is common in bipolar disorder. A family study was conducted on the molecular genetics of depression and personality, in which the proband had been treated for depression. All probands and parents or siblings were interviewed with a structured interview and completed the Temperament and Character Inventory. Fourteen per cent of subjects interviewed reported a history of self-mutilation, mostly by wrist cutting. Self-mutilation was more common in bipolar I disorder subjects then in any other diagnostic groups. In multiple logistic regression self-mutilation was predicted by mood disorder diagnosis and harm avoidance, but not by borderline personality disorder. Furthermore, the relatives of non-bipolar depressed probands with self-mutilation had higher rates of bipolar I or II disorder and higher rates of self-mutilation. Sixteen per cent of subjects reported suicide attempts and these were most common in those with bipolar I disorder and in those with borderline personality disorder. On multiple logistic regression, however, only mood disorder diagnosis and harm avoidance predicted suicide attempts. Suicide attempts, unlike self-mutilation, were not familial. Self-mutilation and suicide attempts are only partially overlapping behaviours, although both are predicted by mood disorder diagnosis and harm avoidance. Self-mutilation has a particularly strong association with bipolar disorder. Clinicians need to think of bipolar disorder, not borderline personality disorder, when assessing an individual who has a history of self-mutilation.

  14. Pivotal roles of Fezf2 in differentiation of cone OFF bipolar cells and functional maturation of cone ON bipolar cells in retina.

    PubMed

    Suzuki-Kerr, Haruna; Iwagawa, Toshiro; Sagara, Hiroshi; Mizota, Atsushi; Suzuki, Yutaka; Watanabe, Sumiko

    2018-06-01

    During development of the retina, common retinal progenitor cells give rise to six classes of neurons that subsequently further diversify into more than 55 subtypes of neuronal subtypes. Here, we have investigated the expression and function of Fezf2, Fez zinc finger family of protein, in the developing mouse retina. Expression of Fezf2 transcripts was strongly observed in the embryonic retinal progenitors at E14.5 and declined quickly in subsequent development of retina. Then, in postnatal stage at around day 8, Fezf2 was transiently expressed then declined again. Loss-of-function analysis using retinas from mice in which Fezf2 coding region was substituted with β-galactosidase showed that Fezf2 is expressed in a subset of cone OFF bipolar cells and required for their differentiation. Using electroretinogram, we found that Fezf2 knockout retina exhibited significantly reduced photopic b-wave, suggesting functional abnormality of cone ON bipolar cells. Furthermore, reduced expression of synaptic protein Trpm1 and structural alteration of ON bipolar cell invagination, both of which affected cone photoreceptor terminal synaptic activity, was identified by transmission electron microscopy and immunohistochemistry, respectively. Taken together, our results show that Fezf2 is indispensable in differentiation of bipolar precursors into cone OFF bipolar cells and in functional maturation of cone ON bipolar cells during development of mouse retina. These results contribute to our understanding of how diversity of neuronal subtypes and hence specificity of neuronal connections are established in the retina by intrinsic cues. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Gaining Insight of Fetal Brain Development with Diffusion MRI and Histology

    PubMed Central

    Huang, Hao; Vasung, Lana

    2013-01-01

    Human brain is extraordinarily complex and yet its origin is a simple tubular structure. Its development during the fetal period is characterized by a series of accurately organized events which underlie the mechanisms of dramatic structural changes during fetal development. Revealing detailed anatomy at different stages of human fetal brain development provides insight on understanding not only this highly ordered process, but also the neurobiological foundations of cognitive brain disorders such as mental retardation, autism, schizophrenia, bipolar and language impairment. Diffusion tensor imaging (DTI) and histology are complementary tools which are capable of delineating the fetal brain structures at both macroscopic and microscopic level. In this review, the structural development of the fetal brains has been characterized with DTI and histology. Major components of the fetal brain, including cortical plate, fetal white matter and cerebral wall layer between the ventricle and subplate, have been delineated with DTI and histology. Anisotropic metrics derived from DTI were used to quantify the microstructural changes during the dynamic process of human fetal cortical development and prenatal development of other animal models. Fetal white matter pathways have been traced with DTI-based tractography to reveal growth patterns of individual white matter tracts and corticocortical connectivity. These detailed anatomical accounts of the structural changes during fetal period may provide the clues of detecting developmental and cognitive brain disorders at their early stages. The anatomical information from DTI and histology may also provide reference standards for diagnostic radiology of premature newborns. PMID:23796901

  16. Genetic Relationships Between Schizophrenia, Bipolar Disorder, and Schizoaffective Disorder

    PubMed Central

    Cardno, Alastair G.

    2014-01-01

    There is substantial evidence for partial overlap of genetic influences on schizophrenia and bipolar disorder, with family, twin, and adoption studies showing a genetic correlation between the disorders of around 0.6. Results of genome-wide association studies are consistent with commonly occurring genetic risk variants, contributing to both the shared and nonshared aspects, while studies of large, rare chromosomal structural variants, particularly copy number variants, show a stronger influence on schizophrenia than bipolar disorder to date. Schizoaffective disorder has been less investigated but shows substantial familial overlap with both schizophrenia and bipolar disorder. A twin analysis is consistent with genetic influences on schizoaffective episodes being entirely shared with genetic influences on schizophrenic and manic episodes, while association studies suggest the possibility of some relatively specific genetic influences on broadly defined schizoaffective disorder, bipolar subtype. Further insights into genetic relationships between these disorders are expected as studies continue to increase in sample size and in technical and analytical sophistication, information on phenotypes beyond clinical diagnoses are increasingly incorporated, and approaches such as next-generation sequencing identify additional types of genetic risk variant. PMID:24567502

  17. Bipolar nebulae and mass loss from red giant stars

    NASA Technical Reports Server (NTRS)

    Cohen, M.

    1985-01-01

    Observations of several bipolar nebulae are used to learn something of the nature of mass loss from the probable red-giant progenitors of these nebulae. Phenomena discussed are: (1) probable GL 2688's optical molecular emissions; (2) newly discovered very high velocity knots along the axis of OH 0739 - 14, which reveal evidence for mass ejections of + or 300 km/s from the M9 III star embedded in this nebula; (3) the bipolar structure of three extreme carbon stars, and the evidence for periodic mass ejection in IRC + 30219, also at high speed (about 80 km/s); and (4) the curious cool TiO-rich region above Parsamian 13, which may represent the very recent shedding of photospheric material from a cool, oxygen-rich giant. Several general key questions about bipolar nebulae that relate to the process of mass loss from their progenitor stars are raised.

  18. Family treatment for bipolar disorder and substance abuse in late adolescence.

    PubMed

    Miklowitz, David J

    2012-05-01

    The initial onset of bipolar disorder occurs in childhood or adolescence in about 50% of patients. Early-onset forms of the disorder have a poorer prognosis than adult-onset forms and are frequently characterized by comorbid substance abuse. Clinical trials research suggests that family psychoeducational approaches are effective adjuncts to medication in stabilizing the symptoms of bipolar disorder in adults and youth, although their efficacy in patients with comorbid substance use disorders has not been systematically investigated. This article describes the family-focused treatment (FFT) of a late adolescent with bipolar disorder and polysubstance dependence. The treatment of this patient and family required adapting FFT to consider the family's structure, dysfunctional alliance patterns, and unresolved conflicts from early in the family's history. The case illustrates the importance of conducting manual-based behavioral family treatments with a psychotherapeutic attitude, including addressing unstated emotional conflicts and resistances that may impede progress. © 2012 Wiley Periodicals, Inc.

  19. Antisocial personality disorder and borderline symptoms are differentially related to impulsivity and course of illness in bipolar disorder.

    PubMed

    Swann, Alan C; Lijffijt, Marijn; Lane, Scott D; Steinberg, Joel L; Moeller, F Gerard

    2013-06-01

    Interactions between characteristics of bipolar and Axis II cluster B disorders are clinically and diagnostically challenging. Characteristics associated with personality disorders may be dimensional aspects of bipolar disorder. We investigated relationships among antisocial personality disorder (ASPD) or borderline personality disorder symptoms, impulsivity, and course of illness in bipolar disorder. Subjects with bipolar disorder were recruited from the community. Diagnosis was by structured clinical interview for DSM-IV (SCID-I and -II), psychiatric symptom assessment by the change version of the schedule for affective disorders and schizophrenia (SADS-C), severity of Axis II symptoms by ASPD and borderline personality disorder SCID-II symptoms, and impulsivity by the Barratt impulsiveness scale (BIS-11). ASPD and borderline symptoms were not related to clinical state or affective symptoms. Borderline symptoms correlated with BIS-11 impulsivity scores, and predicted history of suicide attempts independently of the relationship to impulsivity. ASPD symptoms were more strongly related to course of illness, including early onset, frequent episodes, and substance-related disorders. These effects persisted after allowance for gender and substance-use disorder history. Personality disorder symptoms appear to be dimensional, trait-like characteristics of bipolar disorder. ASPD and Borderline symptoms are differentially related to impulsivity and course of illness. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Perisylvian GABA levels in schizophrenia and bipolar disorder.

    PubMed

    Atagün, Murat İlhan; Şıkoğlu, Elif Muazzez; Soykan, Çağlar; Serdar Süleyman, Can; Ulusoy-Kaymak, Semra; Çayköylü, Ali; Algın, Oktay; Phillips, Mary Louise; Öngür, Dost; Moore, Constance Mary

    2017-01-10

    The aim of this study is to measure GABA levels of perisylvian cortices in schizophrenia and bipolar disorder patients, using proton magnetic resonance spectroscopy ( 1 H-MRS). Patients with schizophrenia (n=25), bipolar I disorder (BD-I; n=28) and bipolar II disorder (BD-II; n=20) were compared with healthy controls (n=30). 1 H-MRS data was acquired using a Siemens 3T whole body scanner to quantify right and left perisylvian structures' (including superior temporal lobes) GABA levels. Right perisylvian GABA values differed significantly between groups [χ 2 =9.62, df: 3, p=0.022]. GABA levels were significantly higher in the schizophrenia group compared with the healthy control group (p=0.002). Furthermore, Chlorpromazine equivalent doses of antipsychotics correlated with right hemisphere GABA levels (r 2 =0.68, p=0.006, n=33). GABA levels are elevated in the right hemisphere in patients with schizophrenia in comparison to bipolar disorder and healthy controls. The balance between excitatory and inhibitory controls over the cortical circuits may have direct relationship with GABAergic functions in auditory cortices. In addition, GABA levels may be altered by brain regions of interest, psychotropic medications, and clinical stage in schizophrenia and bipolar disorder. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Antisocial Personality Disorder and Borderline Symptoms are Differentially Related to Impulsivity and Course of Illness in Bipolar Disorder

    PubMed Central

    Swann, Alan C.; Lijffijt, Marijn; Lane, Scott D.; Steinberg, Joel L.; Moeller, F. Gerard

    2012-01-01

    Background Interactions between characteristics of bipolar and Axis II cluster B disorders are clinically and diagnostically challenging. Characteristics associated with personality disorders may be dimensional aspects of bipolar disorder. We investigated relationships among antisocial personality disorder (ASPD) or borderline personality disorder symptoms, impulsivity, and course of illness in bipolar disorder. Methods Subjects with bipolar disorder were recruited from the community. Diagnosis was by Structured Clinical Interview for DSM-IV (SCID-I and –II), psychiatric symptom assessment by the Change version of the Schedule for Affective Disorders and Schizophrenia (SADS-C), severity of axis II symptoms by ASPD and borderline personality disorder SCID-II symptoms, and impulsivity by the Barratt Impulsiveness Scale (BIS-11). Results ASPD and borderline symptoms were not related to clinical state or affective symptoms. Borderline symptoms correlated with BIS-11 impulsivity scores, and predicted history of suicide attempts independently of the relationship to impulsivity. ASPD symptoms were more strongly related to course of illness, including early onset, frequent episodes, and substance-related disorders. These effects persisted after allowance for gender and substance-use disorder history. Conclusions Personality disorder symptoms appear to be dimensional, trait-like characteristics of bipolar disorder. ASPD and Borderline symptoms are differentially related to impulsivity and course of illness. PMID:22835849

  2. Insight in bipolar mania: evaluation of its heterogeneity and correlation with clinical symptoms.

    PubMed

    Silva, Rafael de Assis da; Mograbi, Daniel C; Bifano, Jaqueline; Santana, Cristina M T; Cheniaux, Elie

    2016-07-15

    Studies on insight in bipolar mania are not numerous and usually consider insight as a unitary construct. Evaluate how different facets of insight are affected in bipolar mania and investigate correlations between insight for each specific object in bipolar disorder and manic symptomatology. A group of 165 bipolar patients were followed during a year, with 51 patients having manic episodes according to DSM-IV-TR criteria. Patients underwent a clinical assessment and insight was evaluated through the Insight Scale for Affective Disorders. The study found that insight regarding symptoms is worse than insight of having bipolar disorder, social relationships and self esteem. Moreover, poor global insight (total ISAD) correlates with more severe changes in mood, speech and thought structure, with worse insight about symptoms correlating with the same alterations and also with more severe symptoms of agitation/energy. Although a large sample of bipolar patients was followed up, the final sample composed of patients with at least one manic episode was relatively smaller. Moreover, the fact that the study was performed in a university hospital may have led to selection biases. Results suggest that patients with BD are reasonably capable of identifying that their condition implies consequences but have more impaired awareness of their energy and activity levels. A lower level of insight specifically about symptoms correlates with more severe symptoms of agitation/energy, which suggests a psychomotor nucleus able to impair insight in mania. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. The relationship of bulimia and anorexia nervosa with bipolar disorder and its temperamental foundations.

    PubMed

    Lunde, Anna V; Fasmer, Ole B; Akiskal, Kareen K; Akiskal, Hagop S; Oedegaard, Ketil J

    2009-06-01

    Earlier studies have suggested a relationship between bipolar disorder (BP) and eating disorders (ED), more specifically, bulimia nervosa (BN) and bipolar II disorder (BP-II). In the present report we extend this relationship to broader definitions of bipolarity. Semi-structured interview of 201 patients with DSM-IV criteria for major affective disorders combined with Akiskal and Mallya criteria for Affective temperaments. To diagnose lifetime comorbid eating disorders DSM-IV criteria for eating disorders (Bulimia Nervosa, BN, Anorexia, AN) were used. 33 patients had an eating disorder. When compared to patients without ED the patients with ED had a higher prevalence of bipolar disorders. Using strict DSM-IV criteria, this association was only significant for BN (OR) 4.5 (95% CI 1.1-17.6). When using a broader index of bipolarity including patients having affective temperaments, a significant relation was found for BN (OR) 9.1 (95% CI 1.1-73.6), and for patients with a lifetime history of both BN and AN (OR) 8.6 (95% CI 1.1-70.2).We also found patients with ED to have a significantly higher prevalence of affective temperaments, an earlier onset of major affective disorder and to have more depressive episodes. Non-blind evaluation of diagnosis for mood, eating disorders and affective temperaments. In line with previous reports we describe an association between bulimia nervosa and bipolar disorder. Furthermore we report a relationship between lifetime bulimia and anorexia and cyclothymic and related affective temperaments.

  4. Cognitions in bipolar affective disorder and unipolar depression: imagining suicide

    PubMed Central

    Hales, Susie A; Deeprose, Catherine; Goodwin, Guy M; Holmes, Emily A

    2011-01-01

    Objective Bipolar disorder has the highest rate of suicide of all the psychiatric disorders. In unipolar depression, individuals report vivid, affect-laden images of suicide or the aftermath of death (flashforwards to suicide) during suicidal ideation but this phenomenon has not been explored in bipolar disorder. Therefore the authors investigated and compared imagery and verbal thoughts related to past suicidality in individuals with bipolar disorder (n = 20) and unipolar depression (n = 20). Methods The study used a quasi-experimental comparative design. The Structured Clinical Interview for DSM-IV was used to confirm diagnoses. Quantitative and qualitative data were gathered through questionnaire measures (e.g., mood and trait imagery use). Individual interviews assessed suicidal cognitions in the form of (i) mental images and (ii) verbal thoughts. Results All participants reported imagining flashforwards to suicide. Both groups reported greater preoccupation with these suicide-related images than with verbal thoughts about suicide. However, compared to the unipolar group, the bipolar group were significantly more preoccupied with flashforward imagery, rated this imagery as more compelling, and were more than twice as likely to report that the images made them want to take action to complete suicide. In addition, the bipolar group reported a greater trait propensity to use mental imagery in general. Conclusions Suicidal ideation needs to be better characterized, and mental imagery of suicide has been a neglected but potentially critical feature of suicidal ideation, particularly in bipolar disorder. Our findings suggest that flashforward imagery warrants further investigation for formal universal clinical assessment procedures. PMID:22085478

  5. Transcranial current stimulation focality using disc and ring electrode configurations: FEM analysis

    NASA Astrophysics Data System (ADS)

    Datta, Abhishek; Elwassif, Maged; Battaglia, Fortunato; Bikson, Marom

    2008-06-01

    We calculated the electric fields induced in the brain during transcranial current stimulation (TCS) using a finite-element concentric spheres human head model. A range of disc electrode configurations were simulated: (1) distant-bipolar; (2) adjacent-bipolar; (3) tripolar; and three ring designs, (4) belt, (5) concentric ring, and (6) double concentric ring. We compared the focality of each configuration targeting cortical structures oriented normal to the surface ('surface-radial' and 'cross-section radial'), cortical structures oriented along the brain surface ('surface-tangential' and 'cross-section tangential') and non-oriented cortical surface structures ('surface-magnitude' and 'cross-section magnitude'). For surface-radial fields, we further considered the 'polarity' of modulation (e.g. superficial cortical neuron soma hyper/depolarizing). The distant-bipolar configuration, which is comparable with commonly used TCS protocols, resulted in diffuse (un-focal) modulation with bi-directional radial modulation under each electrode and tangential modulation between electrodes. Increasing the proximity of the two electrodes (adjacent-bipolar electrode configuration) increased focality, at the cost of more surface current. At similar electrode distances, the tripolar-electrodes configuration produced comparable peak focality, but reduced radial bi-directionality. The concentric-ring configuration resulted in the highest spatial focality and uni-directional radial modulation, at the expense of increased total surface current. Changing ring dimensions, or use of two concentric rings, allow titration of this balance. The concentric-ring design may thus provide an optimized configuration for targeted modulation of superficial cortical neurons.

  6. Confirmatory factor analysis reveals a latent cognitive structure common to bipolar disorder, schizophrenia, and normal controls.

    PubMed

    Schretlen, David J; Peña, Javier; Aretouli, Eleni; Orue, Izaskun; Cascella, Nicola G; Pearlson, Godfrey D; Ojeda, Natalia

    2013-06-01

    We sought to determine whether a single hypothesized latent factor structure would characterize cognitive functioning in three distinct groups. We assessed 576 adults (340 community controls, 126 adults with bipolar disorder, and 110 adults with schizophrenia) using 15 measures derived from nine cognitive tests. Confirmatory factor analysis (CFA) was conducted to examine the fit of a hypothesized six-factor model. The hypothesized factors included attention, psychomotor speed, verbal memory, visual memory, ideational fluency, and executive functioning. The six-factor model provided an excellent fit for all three groups [for community controls, root mean square error of approximation (RMSEA) <0.048 and comparative fit index (CFI) = 0.99; for adults with bipolar disorder, RMSEA = 0.071 and CFI = 0.99; and for adults with schizophrenia, RMSEA = 0.06 and CFI = 0.98]. Alternate models that combined fluency with processing speed or verbal and visual memory reduced the goodness of fit. Multi-group CFA results supported factor invariance across the three groups. Confirmatory factor analysis supported a single six-factor structure of cognitive functioning among patients with schizophrenia or bipolar disorder and community controls. While the three groups clearly differ in level of performance, they share a common underlying architecture of information processing abilities. These cognitive factors could provide useful targets for clinical trials of treatments that aim to enhance information processing in persons with neurological and neuropsychiatric disorders. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. High power bipolar lead-acid batteries

    NASA Technical Reports Server (NTRS)

    Halpert, Gerald; Attia, Alan

    1991-01-01

    The Jet Propulsion Laboratory (JPL), with interest in advanced energy storage systems, is involved in the development of a unique lead acid battery design. This battery utilizes the same combination of lead and lead dioxide active materials present in the automobile starting battery. However, it can provide 2 to 10 times the power while minimizing volume and weight. The typical starting battery is described as a monopolar type using one current collector for both the positive and negative plate of adjacent cells. Specific power as high as 2.5 kW/kg was projected for 30 second periods with as many as 2000 recharge cycles.

  8. How obstetric settings can help address gaps in psychiatric care for pregnant and postpartum women with bipolar disorder.

    PubMed

    Byatt, Nancy; Cox, Lucille; Moore Simas, Tiffany A; Kini, Nisha; Biebel, Kathleen; Sankaran, Padma; Swartz, Holly A; Weinreb, Linda

    2018-03-13

    To elucidate (1) the challenges associated with under-recognition of bipolar disorder in obstetric settings, (2) barriers pregnant and postpartum women with bipolar disorder face when trying to access psychiatric care, and (3) how obstetric settings can identify such women and connect them with mental health services. Structured, in-depth interviews were conducted with 25 pregnant and postpartum women recruited from obstetric practices who scored ≥ 10 on the Edinburgh Postnatal Depression Scale and met DSM-IV criteria for bipolar disorder I, II, or not otherwise specified using the Mini International Neuropsychiatric Interview. Quantitative analyses included descriptive statistics. Interviews were transcribed, and resulting data were analyzed using a grounded theory approach. Most participants (n = 19, 79.17%) did not have a clinical diagnosis of bipolar disorder documented in their medical records nor had received referral for treatment during pregnancy (n = 15, 60%). Of participants receiving pharmacotherapy (n = 14, 58.33%), most were treated with an antidepressant alone (n = 10, 71.42%). Most medication was prescribed by an obstetric (n = 4, 28.57%) or primary care provider (n = 7, 50%). Qualitative interviews indicated that participants want their obstetric practices to proactively screen for, discuss and help them obtain mental health treatment. Women face challenges in securing mental health treatment appropriate to their bipolar illness. Obstetric providers provide the bulk of medical care for these women and need supports in place to (1) better recognize bipolar disorder, (2) avoid inappropriate prescribing practices for women with undiagnosed bipolar disorder, and (3) ensure women are referred to specialized treatment when needed.

  9. Circadian preferences, oxidative stress and inflammatory cytokines in bipolar disorder: A community study.

    PubMed

    Mondin, Thaise Campos; de Azevedo Cardoso, Taiane; Moreira, Fernanda Pedrotti; Wiener, Carolina; Oses, Jean Pierre; de Mattos Souza, Luciano Dias; Jansen, Karen; da Silva Magalhães, Pedro Vieira; Kapczinski, Flávio; da Silva, Ricardo Azevedo

    2016-12-15

    To assess circadian preference among a community sample of people with bipolar disorder, major depression and without any mood disorders. Secondly, we investigated the association of circadian preference with cytokines interleukin-6 (IL-6), interleukin-10 (IL-10) and, tumor necrosis factor alpha (TNF-α) and oxidative stress assessed by thiobarbituric acid reactive substances (TBARS), uric acid and Protein Carbonyl Content (PCC). A cross-sectional study nested in a population-based sample. Caseness was confirmed with the Structured Clinical Interview for DSM-IV. A sample of 215 participants, in whom we measured circadian preferences, IL-6, IL-10, TNF-α, TBARS, uric acid, PCC. Biological rhythms were evaluated using the Biological Interview of Assessment in Neuropsychiatry. Bipolar group presented a higher alteration in biological rhythms (40.40±9.78) when compared with the major depression group (36.35±9.18) and control group (27.61±6.89) p<0.001. Subjects with bipolar disorder who were active at night and had a day/night cycle reverse showed decreased levels of IL-6 (t, 44=2.096; p=0.042), (t, 44=2.213; p=0.032), respectively. In the bipolar disorder group subjects who presented day/night cycle reverse had lower TBARS levels (t, 41=2.612; p=0.013). TNF-α were decreased in subjects more active at night with bipolar disorder. Lower serum levels of IL-6, TNF-α and TBARS were associated with evening preference in bipolar disorder group. These findings suggest that chronotype may alter the levels of interleukins and oxidative stress levels in bipolar and healthy subjects. A better understanding of the role of circadian preferences in levels of interleukins and oxidative stress are needed. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Network dysfunction of emotional and cognitive processes in those at genetic risk of bipolar disorder.

    PubMed

    Breakspear, Michael; Roberts, Gloria; Green, Melissa J; Nguyen, Vinh T; Frankland, Andrew; Levy, Florence; Lenroot, Rhoshel; Mitchell, Philip B

    2015-11-01

    The emotional and cognitive vulnerabilities that precede the development of bipolar disorder are poorly understood. The inferior frontal gyrus-a key cortical hub for the integration of cognitive and emotional processes-exhibits both structural and functional changes in bipolar disorder, and is also functionally impaired in unaffected first-degree relatives, showing diminished engagement during inhibition of threat-related emotional stimuli. We hypothesized that this functional impairment of the inferior frontal gyrus in those at genetic risk of bipolar disorder reflects the dysfunction of broader network dynamics underlying the coordination of emotion perception and cognitive control. To test this, we studied effective connectivity in functional magnetic resonance imaging data acquired from 41 first-degree relatives of patients with bipolar disorder, 45 matched healthy controls and 55 participants with established bipolar disorder. Dynamic causal modelling was used to model the neuronal interaction between key regions associated with fear perception (the anterior cingulate), inhibition (the left dorsolateral prefrontal cortex) and the region upon which these influences converge, namely the inferior frontal gyrus. Network models that embodied non-linear, hierarchical relationships were the most strongly supported by data from our healthy control and bipolar participants. We observed a marked difference in the hierarchical influence of the anterior cingulate on the effective connectivity from the dorsolateral prefrontal cortex to the inferior frontal gyrus that is unique to the at-risk cohort. Non-specific, non-hierarchical mechanisms appear to compensate for this network disturbance. We thus establish a specific network disturbance suggesting dysfunction in the processes that support hierarchical relationships between emotion and cognitive control in those at high genetic risk for bipolar disorder. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Gray Matter Volume Decrease Distinguishes Schizophrenia From Bipolar Offspring During Childhood and Adolescence.

    PubMed

    Sugranyes, Gisela; de la Serna, Elena; Romero, Soledad; Sanchez-Gistau, Vanessa; Calvo, Anna; Moreno, Dolores; Baeza, Inmaculada; Diaz-Caneja, Covadonga M; Sanchez-Gutierrez, Teresa; Janssen, Joost; Bargallo, Nuria; Castro-Fornieles, Josefina

    2015-08-01

    There is increasing support toward the notion that schizophrenia and bipolar disorder share neurodevelopmental underpinnings, although areas of divergence remain. We set out to examine gray matter volume characteristics of child and adolescent offspring of patients with schizophrenia or bipolar disorder comparatively. In this 2-center study, magnetic resonance structural neuroimaging data were acquired in 198 children and adolescents (aged 6-17 years): 38 offspring of patients with schizophrenia, 77 offspring of patients with bipolar disorder, and 83 offspring of community controls. Analyses of global brain volumes and voxel-based morphometry (using familywise error correction) were conducted. There was an effect of group on total cerebral gray matter volume (F = 3.26, p = .041), driven by a decrease in offspring of patients with schizophrenia relative to offspring of controls (p = .035). At a voxel-based level, we observed an effect of group in the left inferior frontal cortex/anterior insula (F = 14.7, p < .001), which was driven by gray matter volume reduction in offspring of patients with schizophrenia relative to both offspring of controls (p = .044) and of patients with bipolar disorder (p < .001). No differences were observed between offspring of patients with bipolar disorder and offspring of controls in either global or voxel-based gray matter volumes. This first comparative study between offspring of patients with schizophrenia and bipolar disorder suggests that gray matter volume reduction in childhood and adolescence may be specific to offspring of patients with schizophrenia; this may index a greater neurodevelopmental impact of risk for schizophrenia relative to bipolar disorder during youth. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  12. Develop and test fuel cell powered on-site integrated total energy systems: Phase 3, full-scale power plant development

    NASA Technical Reports Server (NTRS)

    Kaufman, A.; Pudick, S.; Wang, C. L.; Werth, J.; Whelan, J. A.

    1985-01-01

    A 25 cell stack of the 13 inch x 23 inch cell size (about 4kW) remains on test after 6000 hours, using simulated reformate fuel. A similar stack was previously shut down after 7000 hours on load. These tests were carried out for the purpose of assessing the durability of fuel cell stack components developed through the end of 1983. In light of the favorable results obtained, a 25kW stack that will contain 175 cells of the same size is being constructed using the same technology base. The components for the 25kW stack have been completed. A methanol steam reformer with a design output equivalent to 50kW has been constructed to serve as a hydrogen generator for the 25kW stack. This reformer and the balance of the fuel processing sub system are currently being tested and debugged. The stack technology development program focused on cost reduction in bipolar plates, nonmetallic cooling plates, and current collecting plates; more stable cathode catalyst support materials; more corrosion resistant metal hardware; and shutdown/start up tolerance.

  13. Cross-cultural adaptation, validation and factor structure of the Insight Scale for Affective Disorders.

    PubMed

    de Assis da Silva, Rafael; Mograbi, Daniel C; Camelo, Evelyn V M; Morton, Gregory Duff; Landeira-Fernandez, J; Cheniaux, Elie

    2015-06-01

    In the last few decades, several tools for studying insight in bipolar disorders have been used. Olaya and colleagues developed the Insight Scale for Affective Disorders (ISAD), which consists of a scale measuring insight through hetero evaluation for patients with mood disorders. The objective of this work is to translate and adapt the original English version of the ISAD to Brazilian Portuguese (ISAD-BR) and to conduct an evaluation of its psychometric properties. Adaptation procedures included translation/back-translation and consultation with a panel of experts. 95 patients with the diagnosis of Type 1 bipolar disorder were evaluated with the final version of the ISAD-BR, which was applied, simultaneously, but independently, by two examiners. Internal consistency and inter-rater reliability were explored and the latent structure of the scale was investigated with principal axis factoring and promax rotation. A second-order factor analysis was conducted to test if the scale had a hierarchical factor structure. The ISAD-BR showed good internal consistency and good inter-rater reliability. The analysis pointed to a four-factor solution of the ISAD-BR: awareness of symptoms associated with activity/energy; awareness of having a disorder; awareness of self-esteem and feelings of pleasure; and awareness of social functioning and relationships. The second order factor analysis indicated a hierarchical factor structure for the ISAD-BR, with the four lower-order factors loading on a single higher-order factor. Insight into bipolar disorder is a multidimensional construct, covering different aspects of the condition and its symptomatology. Nevertheless, insight about activity/energy changes may be a crucial aspect of insight into bipolar disorder. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. A clinical measure of suicidal ideation, suicidal behavior, and associated symptoms in bipolar disorder: Psychometric properties of the Concise Health Risk Tracking Self-Report (CHRT-SR).

    PubMed

    Ostacher, Michael J; Nierenberg, Andrew A; Rabideau, Dustin; Reilly-Harrington, Noreen A; Sylvia, Louisa G; Gold, Alexandra K; Shesler, Leah W; Ketter, Terence A; Bowden, Charles L; Calabrese, Joseph R; Friedman, Edward S; Iosifescu, Dan V; Thase, Michael E; Leon, Andrew C; Trivedi, Madhukar H

    2015-12-01

    People with bipolar disorder are at high risk of suicide, but no clinically useful scale has been validated in this population. The aim of this study was to evaluate the psychometric properties in bipolar disorder of the 7- and 12-item versions of the Concise Health Risk Tracking Self-Report (CHRT-SR), a scale measuring suicidal ideation, suicidal behavior, and associated symptoms. The CHRT was administered to 283 symptomatic outpatients with bipolar I or II disorder who were randomized to receive lithium plus optimized personalized treatment (OPT), or OPT without lithium in a six month longitudinal comparative effectiveness trial. Participants were assessed using structured diagnostic interviews, clinician-rated assessments, and self-report questionnaires. The internal consistency (Cronbach α) was 0.80 for the 7-item CHRT-SR and 0.90 for the 12-item CHRT-SR with a consistent factor structure, and three independent factors (current suicidal thoughts and plans, hopelessness, and perceived lack of social support) for the 7-item version. CHRT-SR scores are correlated with measures of depression, functioning, and quality of life, but not with mania scores. The 7- and 12-item CHRT-SR both had excellent psychometric properties in a sample of symptomatic subjects with bipolar disorder. The scale is highly correlated with depression, functioning, and quality of life, but not with mania. Future research is needed to determine whether the CHRT-SR will be able to predict suicide attempts in clinical practice. Published by Elsevier Ltd.

  15. People--things and data--ideas: bipolar dimensions?

    PubMed

    Tay, Louis; Su, Rong; Rounds, James

    2011-07-01

    We examined a longstanding assumption in vocational psychology that people-things and data-ideas are bipolar dimensions. Two minimal criteria for bipolarity were proposed and examined across 3 studies: (a) The correlation between opposite interest types should be negative; (b) after correcting for systematic responding, the correlation should be greater than -.40. In Study 1, a meta-analysis using 26 interest inventories with a sample size of 1,008,253 participants showed that meta-analytic correlations between opposite RIASEC (realistic, investigative, artistic, social, enterprising, conventional) types ranged from -.03 to .18 (corrected meta-analytic correlations ranged from -.23 to -.06). In Study 2, structural equation models (SEMs) were fit to the Interest Finder (IF; Wall, Wise, & Baker, 1996) and the Interest Profiler (IP; Rounds, Smith, Hubert, Lewis, & Rivkin, 1999) with sample sizes of 13,939 and 1,061, respectively. The correlations of opposite RIASEC types were positive, ranging from .17 to .53. No corrected correlation met the criterion of -.40 except for investigative-enterprising (r = -.67). Nevertheless, a direct estimate of the correlation between data-ideas end poles using targeted factor rotation did not reveal bipolarity. Furthermore, bipolar SEMs fit substantially worse than a multiple-factor representation of vocational interests. In Study 3, a two-way clustering solution on IF and IP respondents and items revealed a substantial number of individuals with interests in both people and things. We discuss key theoretical, methodological, and practical implications such as the structure of vocational interests, interpretation and scoring of interest measures for career counseling, and expert RIASEC ratings of occupations.

  16. Developmental status and system studies of the monolithic solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Myles, K. M.

    The monolithic solid oxide fuel cell (MSOFC) was invented at the Argonne National Laboratory in 1983 and is currently being developed by a team consisting of Argonne National Laboratory and Allied-Signal Aerospace/AiResearch. The MSOFC is an oxide ceramic structure in which appropriate electronic and ionic conductors are fabricated in a honeycomb shape similar to a block of corrugated paperboard. The electrolyte, which conducts oxygens ions from the air side to the fuel side, is yttria-stabilized zirconia (YSZ). All the other materials, that is, the nickel-YSZ anode, the strontium-doped lanthanum manganite cathode, and the doped lanthanum chromite interconnect (bipolar plate), are electronic conductors. These electronic and ionic conductors are arranged to provide short conduction paths to minimize resistive losses. The power density achievable with the MSOFC is expected to be about 8 kW/kg or 4 kW/l at fuel efficiencies over 50 percent, because of small cell size and low resistive losses in the materials. These performances have been approached in laboratory test fuel cell stacks of nominal 125-W capacities.

  17. Degradation Mechanisms for GaN and GaAs High Speed Transistors

    PubMed Central

    Cheney, David J.; Douglas, Erica A.; Liu, Lu; Lo, Chien-Fong; Gila, Brent P.; Ren, Fan; Pearton, Stephen J.

    2012-01-01

    We present a review of reliability issues in AlGaN/GaN and AlGaAs/GaAs high electron mobility transistors (HEMTs) as well as Heterojunction Bipolar Transistors (HBTs) in the AlGaAs/GaAs materials systems. Because of the complex nature and multi-faceted operation modes of these devices, reliability studies must go beyond the typical Arrhenius accelerated life tests. We review the electric field driven degradation in devices with different gate metallization, device dimensions, electric field mitigation techniques (such as source field plate), and the effect of device fabrication processes for both DC and RF stress conditions. We summarize the degradation mechanisms that limit the lifetime of these devices. A variety of contact and surface degradation mechanisms have been reported, but differ in the two device technologies: For HEMTs, the layers are thin and relatively lightly doped compared to HBT structures and there is a metal Schottky gate that is directly on the semiconductor. By contrast, the HBT relies on pn junctions for current modulation and has only Ohmic contacts. This leads to different degradation mechanisms for the two types of devices.

  18. Theoretical and experimental characterization of the DUal-BAse transistor (DUBAT)

    NASA Astrophysics Data System (ADS)

    Wu, Chung-Yu; Wu, Ching-Yuan

    1980-11-01

    A new A-type integrated voltage controlled differential negative resistance device using an extra effective base region to form a lateral pnp (npn) bipolar transistor beside the original base region of a vertical npn (pnp) bipolar junction transistor, and so called the DUal BAse Transistor (DUBAT), is studied both experimentally and theoretically, The DUBAT has three terminals and is fully comparible with the existing bipolar integrated circuits technologies. Based upon the equivalent circuit of the DUBAT, a simple first-order analytical theory is developed, and important device parameters, such as: the I-V characteristic, the differential negative resistance, and the peak and valley points, are also characterized. One of the proposed integrated structures of the DUBAT, which is similar in structure to I 2L but with similar high density and a normally operated vertical npn transistor, has been successfully fabricated and studied. Comparisons between the experimental data and theoretical analyses are made, and show in satisfactory agreements.

  19. Relapse and hospitalization in patients with schizophrenia and bipolar disorder at the St Amanuel Mental Specialized Hospital, Addis Ababa, Ethiopia: a comparative quantitative cross-sectional study.

    PubMed

    Ayano, Getnet; Duko, Bereket

    2017-01-01

    Relapse and hospital admission are common among, and carry a heavy burden in, patients with schizophrenia and bipolar disorder. The aim of this study was to assess the risk of relapse and hospitalizations in patients with schizophrenia and bipolar disorder at the St Amanuel Mental Specialized Hospital, Addis Ababa, Ethiopia. A hospital-based comparative cross-sectional study was conducted in June 2016. Systematic random sampling technique was used to recruit 521 (260 schizophrenia cases and 261 bipolar disorder cases) study participants. Face-to-face interviews were conducted by trained psychiatry professionals. Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) criteria and Structured Clinical Interview of DSM-IV (SCID) were used. The risk of relapse and hospitalizations was slightly higher in patients with bipolar disorder than in patients with schizophrenia. A majority of schizophrenic (213 [81.92%]) and bipolar (215 [82.37%]) patients had a history of hospital admission, and 228 (87.69%) schizophrenic and 230 (88.12%) bipolar patients had a history of relapse. Patients who had a history of hospitalizations also had co-occurring substance use disorders compared to those who had no history of hospitalizations for schizophrenia (81.5% vs 37.9%) and bipolar disorder (82.56% vs 38.2%), respectively. Similarly, those patients who had a history of relapse had high comorbid substance use disorders than those who had no history of relapse for both schizophrenia (87.88% vs 47.37%) and bipolar disorder (88.37% vs 47.19%), respectively. It is vital that, in the local context, mental health professionals strengthen their therapeutic relationships with patients and their caregivers. This might enable patients and their caregivers to express their needs and concerns to them, as well as help to plan proper interventions for patients. Attention needs to be given to screening for comorbid substance use disorders in patients with schizophrenia and bipolar disorder, especially in those who have had a history of relapse and hospitalizations.

  20. Sex dependence of brain size and shape in bipolar disorder: an exploratory study.

    PubMed

    Mackay, Clare E; Roddick, Elina; Barrick, Thomas R; Lloyd, Adrian J; Roberts, Neil; Crow, Tim J; Young, Allan H; Ferrier, I Nicol

    2010-05-01

    Anomalies of asymmetry and sex differences in brain structure have frequently been described in schizophrenic illnesses but have seldom been explored in bipolar disorder. We measured volumes of the left and right frontal, temporal, parietal, and occipital lobes and computed the magnitude of brain torque (i.e., rightward frontal and leftward occipital asymmetry) for 49 patients with bipolar disorder and 47 healthy controls and performed an exploratory analysis of sex differences in patients and controls. Patients had significantly greater cerebrospinal fluid volume than controls, but no difference in total brain volume. There were no main effects of diagnosis in gray matter lobe volume or brain torque, but when analyses were performed separately for male and female subjects, significant sex-by-diagnosis interactions were found in the volume of the left frontal, left temporal, right parietal, and right occipital lobes, such that male patients with bipolar disorder tend toward larger, more symmetric brains than male controls, whereas female patients tend toward smaller, more asymmetric brains than female controls. The lateralised nature of these interactions was such that the normal sex difference in volume was significantly accentuated, whilst the normal sex difference in asymmetry tended to be diminished in patients with bipolar disorder. We conclude that bipolar disorder in part reflects an interaction between brain growth and sex along the anterior-posterior axis of the human brain.

  1. Paleomagnetic evidence for Late Miocene counterclockwise rotation of north coast carbonate sequence, Puerto Rico

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reid, J.A.; Plumley, P.W.; Schellekens, J.H.

    1991-03-01

    A paleomagnetic study of the essentially undeformed middle Tertiary carbonate sequence along the north coast of Puerto Rico reveals statistically significant pre-Pliocene discordance of characteristic component directions against those expected from cratonic North America for much of the section. Despite generally weak to moderately weak magnetic intensities, confirmation of the magnetization as primary in origin comes from the presence of two distinct components of magnetization, intrasite bipolarity, and/or the reproducibility of measurements. The mean geographic direction for the upper Oligocene to middle Miocene strata is 335.2{degree}/32.9{degree} and the corrected mean paleomagnetic pole is 207.6{degree}/66.5{degree}, (N = 3, {alpha}95 = 4.3{degree}).more » This suggests a counter-clockwise (CCW) block rotation of Puerto Rico and its microplate of 24.5{degrees} ({plus minus} 5.8{degrees}) during the late Miocene. Using a width of 250 km for the Northern Caribbean Plate Boundary Zone (NCPBZ) between the North American Plate and Caribbean Plate, the mean left lateral displacement implied is 1.8 to 2.4 cm/yr, which agrees fairly well with published relative motion rates for the two plates. Average rotation rate for 50 Ma to 20 Ma was 0.7{degree}/my but perhaps as great as 4{degree}/my in the Miocene. Resolution of mean paleolatitude indicates northward motion of a degree or less during the period of rotation. Causes of this short-lived rotation may include (1) tectonic escape from the inhibiting presence of the Bahama Banks and Beata Ridge during eastward motion of Puerto Rico along the sinistral transpressive Puerto Rico Trench and Muertos Trough fault systems or (2) changes in relative plate motions of the Caribbean and North American Plate during the late Miocene.« less

  2. Can personality traits predict increases in manic and depressive symptoms?

    PubMed

    Lozano, B E; Johnson, S L

    2001-03-01

    There has been limited research investigating personality traits as predictors of manic and depressive symptoms in bipolar individuals. The present study investigated the relation between personality traits and the course of bipolar disorder. The purpose of this study was to identify specific personality traits that predict the course of manic and depressive symptoms experienced by bipolar individuals. The sample consisted of 39 participants with bipolar I disorder assessed by the Structured Clinical Interview for DSM-IV. Personality was assessed using the NEO Five-Factor Inventory. The Modified Hamilton Rating Scale for Depression and the Bech-Rafaelsen Mania Rating Scale were used to assess symptom severity on a monthly basis. Consistent with previous research on unipolar depression, high Neuroticism predicted increases in depressive symptoms across time while controlling for baseline symptoms. Additionally, high Conscientiousness, particularly the Achievement Striving facet, predicted increases in manic symptoms across time. The current study was limited by the small number of participants, the reliance on a shortened version of a self-report personality measure, and the potential state-dependency of the personality measures. Specific personality traits may assist in predicting bipolar symptoms across time. Further studies are needed to tease apart the state-dependency of personality.

  3. Symptoms and treatment of bipolar patients in Sweden.

    PubMed

    Adler, Mats; Backlund, Lena; Edman, Gunnar; Ösby, Urban

    2012-09-01

    The objective of the study was to investigate affective symptoms and pharmacological treatment in bipolar I disorder patients, and to test whether self-rated symptoms could predict hospital admissions during a 12-month follow-up period. A total of 231 outpatients with clinical bipolar I disorder were recruited. The clinical diagnoses were reassessed by a semi-structured interview. Twenty-four patients (10%) was reclassified as bipolar disorder type II or schizoaffective disorder (bipolar type). Medication status was recorded and symptoms were assessed with the self-rating scale AS-18. Patients were prospectively followed for 12 months and hospitalizations during that time were recorded. More than half (60%) rated themselves as normothymic. Mixed affective symptoms were more common than either depressive or manic/hypomanic symptoms. The admission rate during 1 year of follow-up was 13% (95% C.I. 8-17%). Patients which at baseline rated themselves high in either mania or in depression had a significantly increased risk for hospitalization (OR = 3.15; 95% C.I. 1.38-7.19). The findings should encourage clinicians to use patient self ratings in order to identify patients with a high risk for hospitalization for targeted interventions.

  4. Association between therapeutic alliance, care satisfaction, and pharmacological adherence in bipolar disorder.

    PubMed

    Sylvia, Louisa G; Hay, Aleena; Ostacher, Michael J; Miklowitz, David J; Nierenberg, Andrew A; Thase, Michael E; Sachs, Gary S; Deckersbach, Thilo; Perlis, Roy H

    2013-06-01

    We sought to understand the association of specific aspects of care satisfaction, such as patients' perceived relationship with their psychiatrist and access to their psychiatrist and staff, and therapeutic alliance with participants' likelihood to adhere to their medication regimens among patients with bipolar disorder. We examined data from the multicenter Systematic Treatment Enhancement Program for Bipolar Disorder, an effectiveness study investigating the course and treatment of bipolar disorder. We expected that participants (n = 3037) with positive perceptions of their relationship with their psychiatrist and quality of psychopharmacologic care, as assessed by the Helping Alliance Questionnaire and Care Satisfaction Questionnaire, would be associated with better medication adherence. We utilized logistic regression models controlling for already established factors associated with poor adherence. Patients' perceptions of collaboration, empathy, and accessibility were significantly associated with adherence to treatment in individuals with bipolar disorder completing at least 1 assessment. Patients' perceptions of their psychiatrists' experience, as well as of their degree of discussing medication risks and benefits, were not associated with medication adherence. Patients' perceived therapeutic alliance and treatment environment impact their adherence to pharmacotherapy recommendations. This study may enable psychopharmacologists' practices to be structured to maximize features associated with greater medication adherence.

  5. A diagnosis of bipolar spectrum disorder predicts diagnostic conversion from unipolar depression to bipolar disorder: a 5-year retrospective study.

    PubMed

    Woo, Young Sup; Shim, In Hee; Wang, Hee-Ryung; Song, Hoo Rim; Jun, Tae-Youn; Bahk, Won-Myong

    2015-03-15

    The major aims of this study were to identify factors that may predict the diagnostic conversion from major depressive disorder (MDD) to bipolar disorder (BP) and to evaluate the predictive performance of the bipolar spectrum disorder (BPSD) diagnostic criteria. The medical records of 250 patients with a diagnosis of MDD for at least 5 years were retrospectively reviewed for this study. The diagnostic conversion from MDD to BP was observed in 18.4% of 250 MDD patients, and the diagnostic criteria for BPSD predicted this conversion with high sensitivity (0.870) and specificity (0.917). A family history of BP, antidepressant-induced mania/hypomania, brief major depressive episodes, early age of onset, antidepressant wear-off, and antidepressant resistance were also independent predictors of this conversion. This study was conducted using a retrospective design and did not include structured diagnostic interviews. The diagnostic criteria for BPSD were highly predictive of the conversion from MDD to BP, and conversion was associated with several clinical features of BPSD. Thus, the BPSD diagnostic criteria may be useful for the prediction of bipolar diathesis in MDD patients. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Nonparametric Bayesian clustering to detect bipolar methylated genomic loci.

    PubMed

    Wu, Xiaowei; Sun, Ming-An; Zhu, Hongxiao; Xie, Hehuang

    2015-01-16

    With recent development in sequencing technology, a large number of genome-wide DNA methylation studies have generated massive amounts of bisulfite sequencing data. The analysis of DNA methylation patterns helps researchers understand epigenetic regulatory mechanisms. Highly variable methylation patterns reflect stochastic fluctuations in DNA methylation, whereas well-structured methylation patterns imply deterministic methylation events. Among these methylation patterns, bipolar patterns are important as they may originate from allele-specific methylation (ASM) or cell-specific methylation (CSM). Utilizing nonparametric Bayesian clustering followed by hypothesis testing, we have developed a novel statistical approach to identify bipolar methylated genomic regions in bisulfite sequencing data. Simulation studies demonstrate that the proposed method achieves good performance in terms of specificity and sensitivity. We used the method to analyze data from mouse brain and human blood methylomes. The bipolar methylated segments detected are found highly consistent with the differentially methylated regions identified by using purified cell subsets. Bipolar DNA methylation often indicates epigenetic heterogeneity caused by ASM or CSM. With allele-specific events filtered out or appropriately taken into account, our proposed approach sheds light on the identification of cell-specific genes/pathways under strong epigenetic control in a heterogeneous cell population.

  7. Suicidal ideation and attempts among people with severe mental disorder, Addis Ababa, Ethiopia, comparative cross-sectional study.

    PubMed

    Duko, Bereket; Ayano, Getinet

    2018-01-01

    People with severe mental disorders are associated with increased risk of suicide and suicide attempts compared to the general population. In low and middle-income countries, research concerning suicide attempts and completed suicide among people living with severe mental disorder is limited. The objective of this study was to assess suicide and attempts in people with severe mental disorder at Amanuel Mental Specialized Hospital, Addis Ababa, Ethiopia. Institution-based cross-sectional study was conducted in August-September 2016. Patients with schizophrenia and bipolar disorder were selected using systematic random-sampling technique. The composite international diagnostic interview was used to assess suicide that was administered by psychiatry professionals. Substance use disorder was assessed through face-to-face interviews using structured clinical interview of DSM-IV. A total of 542 (272 schizophrenia + 270 bipolar disorder) patients were included in the study. One hundred nineteen (43.75%) of schizophrenic participants and 128 (47.1%) of bipolar participants have suicidal ideation. Fifty-six (20.7%) of schizophrenic participants and 58 (21.3%) of bipolar participants have suicidal attempt. Among the schizophrenic and bipolar patients who had suicidal ideation, 31.8 and 32.60% had co-morbid substance use disorder, respectively. In this study, which was performed in Ethiopia, suicidal ideation and attempt were shown to be common problems in people with schizophrenia and bipolar disorder. Co-morbid substance use disorder was a more frequent phenomenon among patients with suicidal ideation and attempt. Attention should be given to screen and assess suicidal ideation and attempt in persons with schizophrenia and bipolar disorder.

  8. Differentiating unipolar and bipolar depression by alterations in large-scale brain networks.

    PubMed

    Goya-Maldonado, Roberto; Brodmann, Katja; Keil, Maria; Trost, Sarah; Dechent, Peter; Gruber, Oliver

    2016-02-01

    Misdiagnosing bipolar depression can lead to very deleterious consequences of mistreatment. Although depressive symptoms may be similarly expressed in unipolar and bipolar disorder, changes in specific brain networks could be very distinct, being therefore informative markers for the differential diagnosis. We aimed to characterize specific alterations in candidate large-scale networks (frontoparietal, cingulo-opercular, and default mode) in symptomatic unipolar and bipolar patients using resting state fMRI, a cognitively low demanding paradigm ideal to investigate patients. Networks were selected after independent component analysis, compared across 40 patients acutely depressed (20 unipolar, 20 bipolar), and 20 controls well-matched for age, gender, and education levels, and alterations were correlated to clinical parameters. Despite comparable symptoms, patient groups were robustly differentiated by large-scale network alterations. Differences were driven in bipolar patients by increased functional connectivity in the frontoparietal network, a central executive and externally-oriented network. Conversely, unipolar patients presented increased functional connectivity in the default mode network, an introspective and self-referential network, as much as reduced connectivity of the cingulo-opercular network to default mode regions, a network involved in detecting the need to switch between internally and externally oriented demands. These findings were mostly unaffected by current medication, comorbidity, and structural changes. Moreover, network alterations in unipolar patients were significantly correlated to the number of depressive episodes. Unipolar and bipolar groups displaying similar symptomatology could be clearly distinguished by characteristic changes in large-scale networks, encouraging further investigation of network fingerprints for clinical use. Hum Brain Mapp 37:808-818, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  9. Cognitions in bipolar affective disorder and unipolar depression: imagining suicide.

    PubMed

    Hales, Susie A; Deeprose, Catherine; Goodwin, Guy M; Holmes, Emily A

    2011-01-01

    Bipolar disorder has the highest rate of suicide of all the psychiatric disorders. In unipolar depression, individuals report vivid, affect-laden images of suicide or the aftermath of death (flashforwards to suicide) during suicidal ideation but this phenomenon has not been explored in bipolar disorder. Therefore the authors investigated and compared imagery and verbal thoughts related to past suicidality in individuals with bipolar disorder (n = 20) and unipolar depression (n = 20). The study used a quasi-experimental comparative design. The Structured Clinical Interview for DSM-IV was used to confirm diagnoses. Quantitative and qualitative data were gathered through questionnaire measures (e.g., mood and trait imagery use). Individual interviews assessed suicidal cognitions in the form of (i) mental images and (ii) verbal thoughts. All participants reported imagining flashforwards to suicide. Both groups reported greater preoccupation with these suicide-related images than with verbal thoughts about suicide. However, compared to the unipolar group, the bipolar group were significantly more preoccupied with flashforward imagery, rated this imagery as more compelling, and were more than twice as likely to report that the images made them want to take action to complete suicide. In addition, the bipolar group reported a greater trait propensity to use mental imagery in general. Suicidal ideation needs to be better characterized, and mental imagery of suicide has been a neglected but potentially critical feature of suicidal ideation, particularly in bipolar disorder. Our findings suggest that flashforward imagery warrants further investigation for formal universal clinical assessment procedures. © 2011 John Wiley and Sons A/S.

  10. Cognitive behavioral therapy for insomnia in euthymic bipolar disorder: study protocol for a randomized controlled trial.

    PubMed

    Steinan, Mette Kvisten; Krane-Gartiser, Karoline; Langsrud, Knut; Sand, Trond; Kallestad, Håvard; Morken, Gunnar

    2014-01-16

    Patients with bipolar disorder experience sleep disturbance, even in euthymic phases. Changes in sleep pattern are frequent signs of a new episode of (hypo)mania or depression. Cognitive behavioral therapy for insomnia (CBT-I) is an effective treatment for primary insomnia, but there are no published results on the effects of CBT-I in patients with bipolar disorder. In this randomized controlled trial, we wish to compare CBT-I and treatment as usual with treatment as usual alone to determine its effect in improving quality of sleep, stabilizing minor mood variations and preventing new mood episodes in euthymic patients with bipolar disorder and comorbid insomnia. Patients with euthymic bipolar I or II disorder and insomnia, as verified by the Structured Clinical Interview for DSM Disorders (SCID-1) assessment, will be included. The patients enter a three-week run-in phase in which they complete a sleep diary and a mood diary, are monitored for seven consecutive days with an actigraph and on two of these nights with polysomnography in addition before randomization to an eight-week treatment trial. Treatment as usual consists of pharmacological and supportive psychosocial treatment. In this trial, CBT-I will consist of sleep restriction, psychoeducation about sleep, stabilization of the circadian rhythm, and challenging and correcting sleep state misperception, in three to eight sessions. This trial could document a new treatment for insomnia in bipolar disorder with possible effects on sleep and on stability of mood. In addition, more precise information can be obtained about the character of sleep disturbance in bipolar disorder. ClinicalTrials.gov: NCT01704352.

  11. The structure of protostellar accretion disks and the origin of bipolar flows

    NASA Technical Reports Server (NTRS)

    Wardle, Mark; Koenigl, Arieh

    1993-01-01

    Equations are obtained which govern the disk-wind structure and identify the physical parameters relevant to circumstellar disks. The system of equations is analyzed in the thin-disk approximation, and it is shown that the system can be consistently reduced to a set of ordinary differential equations in z. Representative solutions are presented, and it is shown that the apparent paradox discussed by Shu (1991) is resolved when the finite thickness of the disk is taken into account. Implications of the results for the origin of bipolar flows in young stellar objects and possible application to active galactic nuclei are discussed.

  12. The effects of lithium and anticonvulsants on brain structure in bipolar disorder.

    PubMed

    Germaná, C; Kempton, M J; Sarnicola, A; Christodoulou, T; Haldane, M; Hadjulis, M; Girardi, P; Tatarelli, R; Frangou, S

    2010-12-01

    To investigate the effect of lithium, anticonvulsants and antipsychotics on brain structure in bipolar disorder (BD). A cross-sectional structural brain magnetic resonance imaging study of 74 remitted patients with BD, aged 18-65, who were receiving long-term prophylactic treatment with lithium or anticonvulsants or antipsychotics. Global and regional grey matter, white matter, and cerebrospinal fluid volumes were compared between treatment groups. Grey matter in the subgenual anterior cingulate gyrus on the right (extending into the hypothalamus) and in the postcentral gyrus, the hippocampus/amygdale complex and the insula on the left was greater in BD patients on lithium treatment compared to all other treatment groups. Lithium treatment in BD has a significant effect on brain structure particularly in limbic/paralimbic regions associated with emotional processing. © 2010 John Wiley & Sons A/S.

  13. Subdomains of gender-related occupational interests: do they form a cohesive bipolar M-F dimension?

    PubMed

    Lippa, Richard A

    2005-06-01

    In four studies, with a total of 1780 male and 2969 female participants, subdomains of masculine and feminine occupations were identified from sets of occupational preference items. Identified masculine subdomains included "blue-collar realistic" (e.g., carpenter), "educated realistic" (electrical engineer), and "flashy, risk-taking" (jet pilot). Feminine subdomains included "fashion-related" (fashion model), "artistic" (author), "helping" (social worker), and "children-related" (manager of childcare center). In all studies, principal components analyses of subdomain preference scales showed that masculine subdomains were bipolar opposites of feminine subdomains. This bipolar structure emerged in analyses conducted on combined-sex groups, high-school boys, high-school girls, men, women, heterosexual men, gay men, heterosexual women, and lesbian women. The results suggest that, although there are distinct masculine and feminine occupational subdomains, gender-related occupational preferences, nonetheless, form a replicable, cohesive, bipolar individual difference dimension, which is not an artifact of studying mixed-sex or mixed-sexual-orientation groups.

  14. Comorbidity of obsessive-compulsive disorder in recovered inpatients with bipolar disorder.

    PubMed

    Krüger, S; Bräunig, P; Cooke, R G

    2000-03-01

    To determine the frequency of obsessive-compulsive disorder (OCD) in inpatient subjects with bipolar disorder (BD) and to examine the clinical characteristics of BD subjects with OCD. The sample consisted of 143 inpatient subjects with DSM-III-R BD-I and BD-NOS (BD-II), recovered from a current episode of either depression or mania. Demographic and clinical variables were obtained on the day of admission. Current comorbid conditions including OCD were determined by the Structured Clinical Interview for DSM-III-R Ifollowing recovery from the acute affective episode. The frequency of current OCD was 7% (N = 10). All BD subjects with OCD were BD-II, were male, and had a diagnosis of current dysthymia. They had fewer episodes and a higher incidence of prior suicide attempts than bipolar subjects without OCD. None of the bipolar subjects with OCD fulfilled criteria for cyclothymia. Our findings suggest that BD-II, OCD, dysthymia, and suicidality cluster together in some subjects with BD. We discuss the clinical implications of our findings.

  15. Gaining insight of fetal brain development with diffusion MRI and histology.

    PubMed

    Huang, Hao; Vasung, Lana

    2014-02-01

    Human brain is extraordinarily complex and yet its origin is a simple tubular structure. Its development during the fetal period is characterized by a series of accurately organized events which underlie the mechanisms of dramatic structural changes during fetal development. Revealing detailed anatomy at different stages of human fetal brain development provides insight on understanding not only this highly ordered process, but also the neurobiological foundations of cognitive brain disorders such as mental retardation, autism, schizophrenia, bipolar and language impairment. Diffusion tensor imaging (DTI) and histology are complementary tools which are capable of delineating the fetal brain structures at both macroscopic and microscopic levels. In this review, the structural development of the fetal brains has been characterized with DTI and histology. Major components of the fetal brain, including cortical plate, fetal white matter and cerebral wall layer between the ventricle and subplate, have been delineated with DTI and histology. Anisotropic metrics derived from DTI were used to quantify the microstructural changes during the dynamic process of human fetal cortical development and prenatal development of other animal models. Fetal white matter pathways have been traced with DTI-based tractography to reveal growth patterns of individual white matter tracts and corticocortical connectivity. These detailed anatomical accounts of the structural changes during fetal period may provide the clues of detecting developmental and cognitive brain disorders at their early stages. The anatomical information from DTI and histology may also provide reference standards for diagnostic radiology of premature newborns. Copyright © 2013 ISDN. Published by Elsevier Ltd. All rights reserved.

  16. Bipolar stacked quasi-all-solid-state lithium secondary batteries with output cell potentials of over 6 V

    PubMed Central

    Matsuo, Takahiro; Gambe, Yoshiyuki; Sun, Yan; Honma, Itaru

    2014-01-01

    Designing a lithium ion battery (LIB) with a three-dimensional device structure is crucial for increasing the practical energy storage density by avoiding unnecessary supporting parts of the cell modules. Here, we describe the superior secondary battery performance of the bulk all-solid-state LIB cell and a multilayered stacked bipolar cell with doubled cell potential of 6.5 V, for the first time. The bipolar-type solid LIB cell runs its charge/discharge cycle over 200 times in a range of 0.1–1.0 C with negligible capacity decrease despite their doubled output cell potentials. This extremely high performance of the bipolar cell is a result of the superior battery performance of the single cell; the bulk all-solid-state cell has a charge/discharge cycle capability of over 1500 although metallic lithium and LiFePO4 are employed as anodes and cathodes, respectively. The use of a quasi-solid electrolyte consisting of ionic liquid and Al2O3 nanoparticles is considered to be responsible for the high ionic conductivity and electrochemical stability at the interface between the electrodes and the electrolyte. This paper presents the effective applications of SiO2, Al2O3, and CeO2 nanoparticles and various Li+ conducting ionic liquids for the quasi-solid electrolytes and reports the best ever known cycle performances. Moreover, the results of this study show that the bipolar stacked three-dimensional device structure would be a smart choice for future LIBs with higher cell energy density and output potential. In addition, our report presents the advantages of adopting a three-dimensional cell design based on the solid-state electrolytes, which is of particular interest in energy-device engineering for mobile applications. PMID:25124398

  17. Metabolic syndrome in a French cohort of patients with bipolar disorder: results from the FACE-BD cohort.

    PubMed

    Godin, Ophélia; Etain, Bruno; Henry, Chantal; Bougerol, Thierry; Courtet, Philippe; Mayliss, Leroux; Passerieux, Christine; Azorin, Jean-Michel; Kahn, Jean-Pierre; Gard, Sebastien; Costagliola, Dominique; Leboyer, Marion

    2014-10-01

    The aim of this study was to estimate the prevalence of metabolic syndrome (MetS) and its components in a cohort of French patients with bipolar disorder; determine correlations with sociodemographic, clinical, and treatment-related factors; and investigate the gap between optimal care and effective care of the treated patients. 654 bipolar disorder patients from the FACE-BD cohort were included from 2009 to 2012. Sociodemographic and clinical characteristics, lifestyle information, and data on antipsychotic treatment and comorbidities were collected, and a blood sample was drawn. The Structured Clinical Interview for DSM-IV Axis I Disorders was used to confirm the diagnosis of bipolar disorder. Metabolic syndrome was defined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. 18.5% of individuals with bipolar disorder met criteria for MetS. Two-thirds of bipolar disorder patients did not receive adequate treatment for MetS components. Multivariate analysis showed that risk of MetS in men was nearly twice that in women (OR = 1.9; 95% CI, 1.0-3.8), and older patients had a 3.5 times higher risk (95% CI, 1.5-7.8) of developing MetS than patients under the age of 35 years. Moreover, patients receiving antipsychotic treatment had a 2.3 times increased risk (95% CI, 1.2-3.5) of having MetS, independent of other potential confounders. The prevalence of MetS is high in bipolar disorder patients, and there was considerable undertreatment of the components of MetS in this population. The prevention and treatment of cardiovascular diseases in these patients should be assessed systematically. The findings highlight the need for integrated care, with more interaction and coordination between psychiatrists and primary care providers. © Copyright 2014 Physicians Postgraduate Press, Inc.

  18. Independence of familial transmission of mania and depression: results of the NIMH family study of affective spectrum disorders.

    PubMed

    Merikangas, K R; Cui, L; Heaton, L; Nakamura, E; Roca, C; Ding, J; Qin, H; Guo, W; Shugart, Y Y; Yao-Shugart, Y; Zarate, C; Angst, J

    2014-02-01

    The goal of this study is to investigate the familial transmission of the spectrum of bipolar disorder in a nonclinical sample of probands with a broad range of manifestations of mood disorders. The sample included a total of 447 probands recruited from a clinically enriched community screening and their 2082 adult living and deceased first-degree relatives. A best estimate diagnostic procedure that was based on either direct semistructured interview or structured family history information from multiple informants regarding non-interviewed relatives was employed. Results revealed that there was specificity of familial aggregation of bipolar I (BP I; odds ratio (OR)=8.40; 3.27-20.97; h2=0.83) and major depressive disorder (OR=2.26; 1.58-3.22; h2=0.20), but not BP II. The familial aggregation of BP I was primarily attributable to the familial specificity of manic episodes after adjusting for both proband and relative comorbid anxiety and substance use disorders. There was no significant cross-aggregation between mood disorder subtypes suggesting that the familial transmission of manic and major depressive episodes is independent despite the high magnitude of comorbidity between these mood states. These findings confirm those of earlier studies of the familial aggregation of bipolar disorder and major depression in the first nonclinical sample, and the largest family study of bipolar disorder in the USA using contemporary nonhierarchical diagnostic criteria for mood and anxiety disorders. The results suggest that these major components of bipolar disorder may represent distinct underlying pathways rather than increasingly severe manifestations of a common underlying diathesis. Therefore, dissection of the broad bipolar phenotype in genetic studies could actually generate new findings that could index novel biologic pathways underlying bipolar disorder.

  19. Similar Familial Underpinnings for Full and Subsyndromal Pediatric Bipolar Disorder: A Familial Risk Analysis

    PubMed Central

    Wozniak, Janet; Uchida, Mai; Faraone, Stephen V.; Fitzgerald, Maura; Vaudreuil, Carrie; Carrellas, Nicholas; Davis, Jacqueline; Wolenski, Rebecca; Biederman, Joseph

    2017-01-01

    Objectives To examine the validity of subthreshold pediatric bipolar-I (BP-I) disorder, we compared the familial risk for BP-I disorder in child probands with full BP-I disorder, subthreshold BP-I disorder, ADHD, and non-ADHD/non-bipolar disorder controls. Methods Probands were youth ages 6–17 meeting criteria for BP-I disorder, full (N=239) or subthreshold (N=43), and their first degree relatives (N=687 and N=120, respectively). Comparators were youth with ADHD (N=162), controls (N=136), and their first-degree relatives (N=511 and N=411, respectively). We randomly selected 162 non-bipolar ADHD probands and 136 non-bipolar non-ADHD control probands of similar age and sex distribution to the BP-I probands from our case-control ADHD family studies. Psychiatric assessments were made by trained psychometricians using the KSADS-E and SCID structured diagnostic interviews. We analyzed rates of bipolar disorder using multinomial logistic regression. Results Rates of full bipolar-I disorder significantly differed between the four groups (χ23 = 32.72, p<0.001): relatives of full BP-I and relatives of subthreshold BP-I probands had significantly higher rates of full BP-I disorder than relatives of ADHD probands and relatives of control probands. Relatives of full BP-I, subthreshold BP-I, and ADHD probands also had significantly higher rates of major depressive disorder (MDD) compared to relatives of control probands. Conclusions Our results showed that youth with subthreshold BP-I disorder had similarly elevated risk for BP-I disorder and MDD in first-degree relatives as youth with full BP-I disorder. These findings support the diagnostic continuity between subsyndromal and fully syndromatic states of pediatric BP-I disorder. PMID:28544732

  20. Heat removal from bipolar transistor by loop heat pipe with nickel and copper porous structures.

    PubMed

    Nemec, Patrik; Smitka, Martin; Malcho, Milan

    2014-01-01

    Loop heat pipes (LHPs) are used in many branches of industry, mainly for cooling of electrical elements and systems. The loop heat pipe is a vapour-liquid phase-change device that transfers heat from evaporator to condenser. One of the most important parts of the LHP is the porous wick structure. The wick structure provides capillary force to circulate the working fluid. To achieve good thermal performance of LHP, capillary wicks with high permeability and porosity and fine pore radius are expected. The aim of this work was to develop porous structures from copper and nickel powder with different grain sizes. For experiment copper powder with grain size of 50 and 100 μm and nickel powder with grain size of 10 and 25 μm were used. Analysis of these porous structures and LHP design are described in the paper. And the measurements' influences of porous structures in LHP on heat removal from the insulated gate bipolar transistor (IGBT) have been made.

  1. Heat Removal from Bipolar Transistor by Loop Heat Pipe with Nickel and Copper Porous Structures

    PubMed Central

    Smitka, Martin; Malcho, Milan

    2014-01-01

    Loop heat pipes (LHPs) are used in many branches of industry, mainly for cooling of electrical elements and systems. The loop heat pipe is a vapour-liquid phase-change device that transfers heat from evaporator to condenser. One of the most important parts of the LHP is the porous wick structure. The wick structure provides capillary force to circulate the working fluid. To achieve good thermal performance of LHP, capillary wicks with high permeability and porosity and fine pore radius are expected. The aim of this work was to develop porous structures from copper and nickel powder with different grain sizes. For experiment copper powder with grain size of 50 and 100 μm and nickel powder with grain size of 10 and 25 μm were used. Analysis of these porous structures and LHP design are described in the paper. And the measurements' influences of porous structures in LHP on heat removal from the insulated gate bipolar transistor (IGBT) have been made. PMID:24959622

  2. Can Psychological, Social and Demographical Factors Predict Clinical Characteristics Symptomatology of Bipolar Affective Disorder and Schizophrenia?

    PubMed

    Maciukiewicz, Malgorzata; Pawlak, Joanna; Kapelski, Pawel; Łabędzka, Magdalena; Skibinska, Maria; Zaremba, Dorota; Leszczynska-Rodziewicz, Anna; Dmitrzak-Weglarz, Monika; Hauser, Joanna

    2016-09-01

    Schizophrenia (SCH) is a complex, psychiatric disorder affecting 1 % of population. Its clinical phenotype is heterogeneous with delusions, hallucinations, depression, disorganized behaviour and negative symptoms. Bipolar affective disorder (BD) refers to periodic changes in mood and activity from depression to mania. It affects 0.5-1.5 % of population. Two types of disorder (type I and type II) are distinguished by severity of mania episodes. In our analysis, we aimed to check if clinical and demographical characteristics of the sample are predictors of symptom dimensions occurrence in BD and SCH cases. We included total sample of 443 bipolar and 439 schizophrenia patients. Diagnosis was based on DSM-IV criteria using Structured Clinical Interview for DSM-IV. We applied regression models to analyse associations between clinical and demographical traits from OPCRIT and symptom dimensions. We used previously computed dimensions of schizophrenia and bipolar affective disorder as quantitative traits for regression models. Male gender seemed protective factor for depression dimension in schizophrenia and bipolar disorder sample. Presence of definite psychosocial stressor prior disease seemed risk factor for depressive and suicidal domain in BD and SCH. OPCRIT items describing premorbid functioning seemed related with depression, positive and disorganised dimensions in schizophrenia and psychotic in BD. We proved clinical and demographical characteristics of the sample are predictors of symptom dimensions of schizophrenia and bipolar disorder. We also saw relation between clinical dimensions and course of disorder and impairment during disorder.

  3. Usefulness of the Spanish version of the mood disorder questionnaire for screening bipolar disorder in routine clinical practice in outpatients with major depression

    PubMed Central

    2008-01-01

    Background According to some studies, almost 40% of depressive patients – half of them previously undetected – are diagnosed of bipolar II disorder when systematically assessed for hypomania. Thus, instruments for bipolar disorder screening are needed. The Mood Disorder Questionnaire (MDQ) is a self-reported questionnaire validated in Spanish in stable patients with a previously known diagnosis. The purpose of this study is to evaluate in the daily clinical practice the usefulness of the Spanish version of the MDQ in depressive patients. Methods Patients (n = 87) meeting DSM-IV-TR criteria for a major depressive episode, not previously known as bipolar were included. The affective module of the Structured Clinical Interview (SCID) was used as gold standard. Results MDQ screened 24.1% of depressive patients as bipolar, vs. 12.6% according to SCID. For a cut-off point score of 7 positive answers, sensitivity was 72.7% (95% CI = 63.3 – 82.1) and specificity 82.9% (95% CI = 74.9–90.9). Likelihood ratio of positive and negative tests were 4,252 y 0,329 respectively. Limitations The small sample size reduced the power of the study to 62%. Conclusion Sensitivity and specificity of the MDQ were high for screening bipolar disorder in patients with major depression, and similar to the figures obtained in stable patients. This study confirms that MDQ is a useful instrument in the daily clinical assessment of depressive patients. PMID:18498637

  4. [Description of Clinical and Neurocognitive Profiles in Offspring of Bipolar-Type-I Parents From a Multimodal Intervention Program: Prisma].

    PubMed

    Palacio-Ortíz, Juan David; Uribe-Villa, Esteban; Duque-Ríos, Paula; Gutiérrez-Briceño, Paola; Zapata-Henao, Violeta; Peña-Quintero, Cristian Esteban; López-Jaramillo, Carlos

    2015-01-01

    Offspring of bipolar parents are a high risk population for the develop of mental diseases, their study allow determining the genetic risk, early symptoms, prodromes and psychopathology of bipolar disorder. To describe the psychopathological characteristics and neurocognitives profiles of the offspring of bipolar type I parents. And to identify the presence of sub-syndromal symptoms in all the symptom domains. A descriptive and cross-sectional study was conducted on 110 offspring between 6 and 30 years old. Semi-structured diagnostic interviews were performed. The intelectual coeficient was determined and a neuropsychological assessment was performed on 89 offspring. The most prevalent disorder in the offspring was ADHD (27.6%), with major depression (15.5%) and separation anxiety (14.1%) also being prevalent. Seven patients of the sample were diagnosed with bipolar disorder. There was a statistically significant difference between the age groups for ADHD prevalence. The most frequent sub-syndromal symptoms were observed in the disruptive group. Alterations in the cognitive domains: attention, verbal fluency, work memory, and speed of information processing, were observed in the group younger than 18 years. The offspring of bipolar parents have an elevated rate of psychopathology and cognitive alterations. They are a high risk population for the development of mental disease. These subjects also require close longitudinal observation and early and preventive therapeuthic interventions. Copyright © 2014 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  5. Bipolar II and unipolar comorbidity in 153 outpatients with social phobia.

    PubMed

    Perugi, G; Frare, F; Toni, C; Mata, B; Akiskal, H S

    2001-01-01

    Previous studies on social phobia (SP) have focused largely on comorbidity between SP and major depression. Less attention has been devoted to the comorbidity between SP and bipolar disorder. In this retrospective study, we investigated family history, lifetime comorbidity, and demographic and clinical characteristics among 153 outpatients who met DSM-III-R diagnostic criteria for SP. Information regarding axis I diagnoses was obtained using the Structured Clinical Interview for DSM III-R (SCID-UP-R). Social phobic symptoms and the severity of the illness were assessed by the Liebowitz Social Anxiety Scale (LSAS) and the Liebowitz Social Phobic Disorders Rating Scale, Severity (LSPDRS). Patients completed the Hopkins Symptom Checklist (HSCL 90). Fourteen patients (9.1%) satisfied DSM-III-R criteria for lifetime bipolar disorder not otherwise specified (NOS) (bipolar II), while 71 (46.4%) had unipolar major depression and 68 (44.4%) had no lifetime history of major mood disorders. Comorbid panic disorder/agoraphobia (PDA), obsessive-compulsive disorder (OCD), and alcohol abuse were reported more frequently in the bipolar group than in the other two subgroups. Unipolar patients showed higher rates of comordid PDA and OCD compared with SP patients without mood disorders. Severity and generalization of the SP symptoms, prevalent interactional anxiety, multiple comorbidity, and alcohol abuse appeared to be the most relevant consequences of SP-bipolar coexistence. In a significant minority of cases, protracted social anxiety may hypothetically have represented, along with inhibited depression, the dimensional opposite of gregarious hypomania. Copyright 2001 by W.B. Saunders Company

  6. Magnetic field and electric current structure in the chromosphere

    NASA Technical Reports Server (NTRS)

    Dravins, D.

    1974-01-01

    The three-dimensional vector magnetic field structure in the chromosphere above an active region is deduced by using high-resolution H-alpha filtergrams together with a simultaneous digital magnetogram. An analog model of the field is made with 400 metal wires representing field lines that outline the H-alpha structure. The height extent of the field is determined from vertical field-gradient observations around sunspots, from observed fibril heights, and from an assumption that the sources of the field are largely local. The computed electric currents (typically 10 mA/sq m) are found to flow in patterns not similar to observed features and not parallel to magnetic fields. Force structures correspond to observed solar features; the dynamics to be expected include: downward motion in bipolar areas in the lower chromosphere, an outflow of the outer chromosphere into the corona with radially outward flow above bipolar plage regions, and motion of arch filament systems.

  7. Fractal analysis of MRI data for the characterization of patients with schizophrenia and bipolar disorder.

    PubMed

    Squarcina, Letizia; De Luca, Alberto; Bellani, Marcella; Brambilla, Paolo; Turkheimer, Federico E; Bertoldo, Alessandra

    2015-02-21

    Fractal geometry can be used to analyze shape and patterns in brain images. With this study we use fractals to analyze T1 data of patients affected by schizophrenia or bipolar disorder, with the aim of distinguishing between healthy and pathological brains using the complexity of brain structure, in particular of grey matter, as a marker of disease. 39 healthy volunteers, 25 subjects affected by schizophrenia and 11 patients affected by bipolar disorder underwent an MRI session. We evaluated fractal dimension of the brain cortex and its substructures, calculated with an algorithm based on the box-count algorithm. We modified this algorithm, with the aim of avoiding the segmentation processing step and using all the information stored in the image grey levels. Moreover, to increase sensitivity to local structural changes, we computed a value of fractal dimension for each slice of the brain or of the particular structure. To have reference values in comparing healthy subjects with patients, we built a template by averaging fractal dimension values of the healthy volunteers data. Standard deviation was evaluated and used to create a confidence interval. We also performed a slice by slice t-test to assess the difference at slice level between the three groups. Consistent average fractal dimension values were found across all the structures in healthy controls, while in the pathological groups we found consistent differences, indicating a change in brain and structures complexity induced by these disorders.

  8. Fractal analysis of MRI data for the characterization of patients with schizophrenia and bipolar disorder

    NASA Astrophysics Data System (ADS)

    Squarcina, Letizia; De Luca, Alberto; Bellani, Marcella; Brambilla, Paolo; Turkheimer, Federico E.; Bertoldo, Alessandra

    2015-02-01

    Fractal geometry can be used to analyze shape and patterns in brain images. With this study we use fractals to analyze T1 data of patients affected by schizophrenia or bipolar disorder, with the aim of distinguishing between healthy and pathological brains using the complexity of brain structure, in particular of grey matter, as a marker of disease. 39 healthy volunteers, 25 subjects affected by schizophrenia and 11 patients affected by bipolar disorder underwent an MRI session. We evaluated fractal dimension of the brain cortex and its substructures, calculated with an algorithm based on the box-count algorithm. We modified this algorithm, with the aim of avoiding the segmentation processing step and using all the information stored in the image grey levels. Moreover, to increase sensitivity to local structural changes, we computed a value of fractal dimension for each slice of the brain or of the particular structure. To have reference values in comparing healthy subjects with patients, we built a template by averaging fractal dimension values of the healthy volunteers data. Standard deviation was evaluated and used to create a confidence interval. We also performed a slice by slice t-test to assess the difference at slice level between the three groups. Consistent average fractal dimension values were found across all the structures in healthy controls, while in the pathological groups we found consistent differences, indicating a change in brain and structures complexity induced by these disorders.

  9. Abnormal bipolar resistive switching behavior in a Pt/GaO{sub 1.3}/Pt structure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guo, D. Y.; Wu, Z. P.; Zhang, L. J.

    2015-07-20

    A stable and repeatable abnormal bipolar resistive switching behavior was observed in a Pt/GaO{sub 1.3}/Pt sandwich structure without an electroforming process. The low resistance state (LRS) and the high resistance state (HRS) of the device can be distinguished clearly and be switched reversibly under a train of the voltage pulses. The LRS exhibits a conduction of electron tunneling, while the HRS shows a conduction of Schottky-type. The observed phenomena are considered to be related to the migration of oxygen vacancies which changes the space charge region width of the metal/semiconductor interface and results in a different electron transport mechanism.

  10. Characterization of dermal plates from armored catfish Pterygoplichthys pardalis reveals sandwich-like nanocomposite structure.

    PubMed

    Ebenstein, Donna; Calderon, Carlos; Troncoso, Omar P; Torres, Fernando G

    2015-05-01

    Dermal plates from armored catfish are bony structures that cover their body. In this paper we characterized structural, chemical, and nanomechanical properties of the dermal plates from the Amazonian fish Pterygoplichthys pardalis. Analysis of the morphology of the plates using scanning electron microscopy (SEM) revealed that the dermal plates have a sandwich-like structure composed of an inner porous matrix surrounded by two external dense layers. This is different from the plywood-like laminated structure of elasmoid fish scales but similar to the structure of osteoderms found in the dermal armour of some reptiles and mammals. Chemical analysis performed using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) results revealed similarities between the composition of P. pardalis plates and the elasmoid fish scales of Arapaima gigas. Reduced moduli of P. pardalis plates measured using nanoindentation were also consistent with reported values for A. gigas scales, but further revealed that the dermal plate is an anisotropic and heterogeneous material, similar to many other fish scales and osteoderms. It is postulated that the sandwich-like structure of the dermal plates provides a lightweight and tough protective layer. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Bussing Structure In An Electrochemical Cell

    DOEpatents

    Romero, Antonio L.

    2001-06-12

    A bussing structure for bussing current within an electrochemical cell. The bussing structure includes a first plate and a second plate, each having a central aperture therein. Current collection tabs, extending from an electrode stack in the electrochemical cell, extend through the central aperture in the first plate, and are then sandwiched between the first plate and second plate. The second plate is then connected to a terminal on the outside of the case of the electrochemical cell. Each of the first and second plates includes a second aperture which is positioned beneath a safety vent in the case of the electrochemical cell to promote turbulent flow of gasses through the vent upon its opening. The second plate also includes protrusions for spacing the bussing structure from the case, as well as plateaus for connecting the bussing structure to the terminal on the case of the electrochemical cell.

  12. The vibroacoustic response and sound absorption performance of multilayer, microperforated rib-stiffened plates

    NASA Astrophysics Data System (ADS)

    Zhou, Haian; Wang, Xiaoming; Wu, Huayong; Meng, Jianbing

    2017-10-01

    The vibroacoustic response and sound absorption performance of a structure composed of multilayer plates and one rigid back wall are theoretically analyzed. In this structure, all plates are two-dimensional, microperforated, and periodically rib-stiffened. To investigate such a structural system, semianalytical models of one-layer and multilayer plate structures considering the vibration effects are first developed. Then approaches of the space harmonic method and Fourier transforms are applied to a one-layer plate, and finally the cascade connection method is utilized for a multilayer plate structure. Based on fundamental acoustic formulas, the vibroacoustic responses of microperforated stiffened plates are expressed as functions of a series of harmonic amplitudes of plate displacement, which are then solved by employing the numerical truncation method. Applying the inverse Fourier transform, wave propagation, and linear addition properties, the equations of the sound pressures and absorption coefficients for the one-layer and multilayer stiffened plates in physical space are finally derived. Using numerical examples, the effects of the most important physical parameters—for example, the perforation ratio of the plate, sound incident angles, and periodical rib spacing—on sound absorption performance are examined. Numerical results indicate that the sound absorption performance of the studied structure is effectively enhanced by the flexural vibration of the plate in water. Finally, the proposed approaches are validated by comparing the results of stiffened plates of the present work with solutions from previous studies.

  13. Mobility power flow analysis of coupled plate structure subjected to mechanical and acoustic excitation

    NASA Technical Reports Server (NTRS)

    Cuschieri, J. M.

    1992-01-01

    The mobility power flow approach that was previously applied in the derivation of expressions for the vibrational power flow between coupled plate substructures forming an L configuration and subjected to mechanical loading is generalized. Using the generalized expressions, both point and distributed mechanical loads on one or both of the plates can be considered. The generalized approach is extended to deal with acoustic excitation of one of the plate substructures. In this case, the forces (acoustic pressures) acting on the structure are dependent on the response of the structure because of the scattered pressure component. The interaction between the plate structure and the acoustic fluid leads to the derivation of a corrected mode shape for the plates' normal surface velocity and also for the structure mobility functions. The determination of the scattered pressure components in the expressions for the power flow represents an additional component in the power flow balance for the source plate and the receiver plate. This component represents the radiated acoustical power from the plate structure. For a number of coupled plate substrates, the acoustic pressure generated by one substructure will interact with the motion of another substructure. That is, in the case of the L-shaped plate, acoustic interaction exists between the two plate substructures due to the generation of the acoustic waves by each of the substructures. An approach to deal with this phenomena is described.

  14. Proteomic pathway analysis of the hippocampus in schizophrenia and bipolar affective disorder implicates 14-3-3 signaling, aryl hydrocarbon receptor signaling, and glucose metabolism: potential roles in GABAergic interneuron pathology.

    PubMed

    Schubert, Klaus Oliver; Föcking, Melanie; Cotter, David R

    2015-09-01

    Neuropathological changes of the hippocampus have been associated with psychotic disorders such as schizophrenia and bipolar disorder. Recent work has particularly implicated hippocampal GABAergic interneurons in the pathophysiology of these diseases. However, the molecular mechanisms underlying structural and cellular hippocampal pathology remain poorly understood. We used data from comprehensive difference-in-gel electrophoresis (2-D DIGE) investigations of postmortem human hippocampus of people with schizophrenia and bipolar disorder, covering the acidic (isoelectric point (pI) between pH4 and 7) and, separately, the basic (pI between pH6 and 11) sub-proteome, for Ingenuity Pathway Analysis (IPA) of implicated protein networks and pathways. Comparing disease and control cases, we identified 58 unique differentially expressed proteins in schizophrenia, and 70 differentially expressed proteins in bipolar disorder, using mass spectrometry. IPA implicated, most prominently, 14-3-3 and aryl hydrocarbon receptor signaling in schizophrenia, and gluconeogenesis/glycolysis in bipolar disorder. Both disorders were characterized by alterations of proteins involved in the oxidative stress response, mitochondrial function, and protein-endocytosis, -trafficking, -degradation, and -ubiquitination. These findings are interpreted with a focus on GABAergic interneuron pathology in the hippocampus. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Can personality traits predict increases in manic and depressive symptoms?

    PubMed Central

    Lozano, Brian E.; Johnson, Sheri L.

    2010-01-01

    Background There has been limited research investigating personality traits as predictors of manic and depressive symptoms in bipolar individuals. The present study investigated the relation between personality traits and the course of bipolar disorder. The purpose of this study was to identify specific personality traits that predict the course of manic and depressive symptoms experienced by bipolar individuals. Methods The sample consisted of 39 participants with bipolar I disorder assessed by the Structured Clinical Interview for DSM-IV. Personality was assessed using the NEO Five-Factor Inventory. The Modified Hamilton Rating Scale for Depression and the Bech–Rafaelsen Mania Rating Scale were used to assess symptom severity on a monthly basis. Results Consistent with previous research on unipolar depression, high Neuroticism predicted increases in depressive symptoms across time while controlling for baseline symptoms. Additionally, high Conscientiousness, particularly the Achievement Striving facet, predicted increases in manic symptoms across time. Limitations The current study was limited by the small number of participants, the reliance on a shortened version of a self-report personality measure, and the potential state-dependency of the personality measures. Conclusions Specific personality traits may assist in predicting bipolar symptoms across time. Further studies are needed to tease apart the state-dependency of personality. PMID:11246086

  16. Separator plate for a fuel cell

    DOEpatents

    Petri, R.J.; Meek, J.; Bachta, R.P.; Marianowski, L.G.

    1996-04-02

    A separator plate is described for a fuel cell comprising an anode current collector, a cathode current collector and a main plate, the main plate disposed between the anode current collector and the cathode current collector. The anode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the anode side of the separator plate and the cathode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the cathode side of the separator plate. In this manner, the number of components required to manufacture and assemble a fuel cell stack is reduced. 9 figs.

  17. Separator plate for a fuel cell

    DOEpatents

    Petri, Randy J.; Meek, John; Bachta, Robert P.; Marianowski, Leonard G.

    1996-01-01

    A separator plate for a fuel cell comprising an anode current collector, a cathode current collector and a main plate, the main plate disposed between the anode current collector and the cathode current collector. The anode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the anode side of the separator plate and the cathode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the cathode side of the separator plate. In this manner, the number of components required to manufacture and assemble a fuel cell stack is reduced.

  18. Resolving the Lophiostoma bipolare complex: Generic delimitations within Lophiostomataceae.

    PubMed

    Hashimoto, A; Hirayama, K; Takahashi, H; Matsumura, M; Okada, G; Chen, C Y; Huang, J W; Kakishima, M; Ono, T; Tanaka, K

    2018-06-01

    Lophiostoma bipolare was taxonomically revised based on the morphological observations and phylogenetic analyses of molecular data from nuclear rDNA SSU-ITS-LSU, TUB , tef1 , and rpb2 genes. Twenty-nine strains were morphologically similar to Lo . bipolare . A total of 174 sequences were generated from the Lo . bipolare complex. Phylogenetic analyses based on TUB sequence revealed 11 distinct species within the Lo. bipolare complex. Morphological features of the ascospores and the anatomical structure of the ascomata from both field collections as well as axenic culture, which have been reported previously as variable features at intraspecific levels, were compared to evaluate the taxonomic reliability of these features. To clarify the generic position of the 11 species, phylogenetic analyses were done on SSU-ITS-LSU- tef1 - rpb2 gene sequences. The Lo . bipolare complex shared phylogenetic relationships with Pseudolophiostoma and Vaginatispora , and formed an additional five distinct clades from other members of Lophiostomataceae . According to its phylogenetic position, Lo. bipolare sensu stricto was distantly related to Lophiostoma s. str., and formed an independent clade within Lophiostomataceae. Lophiostoma bipolare s. str. could be distinguished from the other lophiostomataceous genera by the clypeus around the ostiolar neck and by the thin and uniformly thick peridium. A novel genus described as Lentistoma was established to accommodate this species, and the epitypification of Lentistoma bipolare (basionym: Massarina bipolaris ) was proposed. Other lineages of the Lo. bipolare complex could not be separated on the basis of the ascospore size and sheath variations, but were distinguished based on ascomatal features, such as the existence of the clypeus, brown hyphae surrounding the peridium, and the contexture of the peridium, which were stable indicators of generic boundaries in Lophiostomataceae . Four additional new genera with five new species were recognised based on these morphological differences: Crassiclypeus ( C . aquaticus ), Flabellascoma ( F . cycadicola and F . minimum ), Leptoparies ( Lep . palmarum ), and Pseudopaucispora ( Pseudop . brunneospora ). Three new species were added to Pseudolophiostoma ( Pseudol . cornisporum , Pseudol . obtusisporum , and Pseudol . tropicum ) and two new species were added to Vaginatispora ( V . amygdali and V . scabrispora ). The re-evaluation of the validity of several previously recognised genera resulted in the introduction of two new genera with new combinations for Lophiostoma pseudoarmatisporum as Parapaucispora pseudoarmatispora and Vaginatispora fuckelii as Neovaginatispora fuckelii .

  19. The burden on informal caregivers of people with bipolar disorder.

    PubMed

    Ogilvie, Alan D; Morant, Nicola; Goodwin, Guy M

    2005-01-01

    Caregivers of people with bipolar disorder may experience a different quality of burden than is seen with other illnesses. A better understanding of their concerns is necessary to improve the training of professionals working with this population. Conceptualizing caregiver burden in a conventional medical framework may not focus enough on issues important to caregivers, or on cultural and social issues. Perceptions of caregivers about bipolar disorder have important effects on levels of burden experienced. It is important to distinguish between caregivers' experience of this subjective burden and objective burden as externally appraised. Caregivers' previous experiences of health services may influence their beliefs about the illness. Caregiver burden is associated with depression, which affects patient recovery by adding stress to the living environment. The objective burden on caregivers of patients with bipolar disorder is significantly higher than for those with unipolar depression. Caregivers of bipolar patients have high levels of expressed emotion, including critical, hostile, or over-involved attitudes. Several measures have been developed to assess the care burden of patients with depressive disorders, but may be inappropriate for patients with bipolar disorder because of its cyclical nature and the stresses arising from manic and hypomanic episodes. Inter-episode symptoms pose another potential of burden in patients with bipolar disorder. Subsyndromal depressive symptoms are common in this phase of the illness, resulting in severe and widespread impairment of function. Despite the importance of assessing caregiver burden in bipolar disorder, relevant literature is scarce. The specific effects of mania and inter-episode symptoms have not been adequately addressed, and there is a lack of existing measures to assess burden adequately, causing uncertainty regarding how best to structure family interventions to optimally alleviate burden. The relatively few studies into caregiver burden in bipolar disorder may largely reflect experiences in the US Veterans Affairs health service, but the findings may be limited in their generalizability. Nevertheless, available data suggest that caregiver burden is high and largely neglected in bipolar disorder. Clinically effective, well-targeted and practically viable interventions are needed. However, services cannot be enhanced on a rational basis without an improved understanding and capacity to measure and target caregiver burden the impact of any change in services be evaluated.

  20. Development of Process Technologies for High-Performance MOS-Based SiC Power Switching Devices

    DTIC Science & Technology

    2007-08-01

    investigated are insulated-gate bipolar transistors ( IGBTs ) in 4H-SiC. The IGBT combines the best aspects of MOS and bipolar power transistors... IGBTs can be thought of as a fusion of a MOSFET and a BJT. The MOSFET provides a high input impedance while the BJT provides conductivity modulation of...region due to conductivity modulation from the forward-biased BJT. The IGBT is structurally identical to a MOSFET, except that the substrate doping

  1. Block-induced Complex Structures Building the Flare-productive Solar Active Region 12673

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yang, Shuhong; Zhang, Jun; Zhu, Xiaoshuai

    Solar active region (AR) 12673 produced 4 X-class, 27 M-class, and numerous lower-class flares during its passage across the visible solar disk in 2017 September. Our study is to answer the questions why this AR was so flare-productive and how the X9.3 flare, the largest one of the past decade, took place. We find that there was a sunspot in the initial several days, and then two bipolar regions emerged nearby it successively. Due to the standing of the pre-existing sunspot, the movement of the bipoles was blocked, while the pre-existing sunspot maintained its quasi-circular shaped umbra only with themore » disappearance of a part of penumbra. Thus, the bipolar patches were significantly distorted, and the opposite polarities formed two semi-circular shaped structures. After that, two sequences of new bipolar regions emerged within the narrow semi-circular zone, and the bipolar patches separated along the curved channel. The new bipoles sheared and interacted with the previous ones, forming a complex topological system, during which numerous flares occurred. At the highly sheared region, a great deal of free energy was accumulated. On September 6, one negative patch near the polarity inversion line began to rapidly rotate and shear with the surrounding positive fields, and consequently the X9.3 flare erupted. Our results reveal that the block-induced complex structures built the flare-productive AR and the X9.3 flare was triggered by an erupting filament due to the kink instability. To better illustrate this process, a block-induced eruption model is proposed for the first time.« less

  2. Analytical and numerical study on cooling flow field designs performance of PEM fuel cell with variable heat flux

    NASA Astrophysics Data System (ADS)

    Afshari, Ebrahim; Ziaei-Rad, Masoud; Jahantigh, Nabi

    2016-06-01

    In PEM fuel cells, during electrochemical generation of electricity more than half of the chemical energy of hydrogen is converted to heat. This heat of reactions, if not exhausted properly, would impair the performance and durability of the cell. In general, large scale PEM fuel cells are cooled by liquid water that circulates through coolant flow channels formed in bipolar plates or in dedicated cooling plates. In this paper, a numerical method has been presented to study cooling and temperature distribution of a polymer membrane fuel cell stack. The heat flux on the cooling plate is variable. A three-dimensional model of fluid flow and heat transfer in cooling plates with 15 cm × 15 cm square area is considered and the performances of four different coolant flow field designs, parallel field and serpentine fields are compared in terms of maximum surface temperature, temperature uniformity and pressure drop characteristics. By comparing the results in two cases, the constant and variable heat flux, it is observed that applying constant heat flux instead of variable heat flux which is actually occurring in the fuel cells is not an accurate assumption. The numerical results indicated that the straight flow field model has temperature uniformity index and almost the same temperature difference with the serpentine models, while its pressure drop is less than all of the serpentine models. Another important advantage of this model is the much easier design and building than the spiral models.

  3. Active vibration control of structures undergoing bending vibrations

    NASA Technical Reports Server (NTRS)

    Pla, Frederic G. (Inventor); Rajiyah, Harindra (Inventor)

    1995-01-01

    An active vibration control subassembly for a structure (such as a jet engine duct or a washing machine panel) undergoing bending vibrations caused by a source (such as the clothes agitator of the washing machine) independent of the subassembly. A piezoceramic actuator plate is vibratable by an applied electric AC signal. The plate is connected to the structure such that vibrations in the plate induced by the AC signal cause canceling bending vibrations in the structure and such that the plate is compressively pre-stressed along the structure when the structure is free of any bending vibrations. The compressive prestressing increases the amplitude of the canceling bending vibrations before the critical tensile stress level of the plate is reached. Preferably, a positive electric DC bias is also applied to the plate in its poling direction.

  4. Nd2-xCexCuO4-y/Nd2-xCexOy boundary and resistive switchings in mesoscopic structures on base of epitaxial Nd1.86Ce0.14CuO4-у films

    NASA Astrophysics Data System (ADS)

    Tulina, N. A.; Rossolenko, A. N.; Ivanov, A. A.; Sirotkin, V. V.; Shmytko, I. M.; Borisenko, I. Yu.; Ionov, A. M.

    2016-08-01

    Reverse and stable bipolar resistive switching effect (BRSE) was observed in planar Nd2-xCex CuO4-y/Nd2-xCexOx/Ag heterostructure. It was shown that the СVС of the BRSE observed has a diode character. Simulations were used to consider the influence of the nonuniform distribution of an electric field at the interface of a heterojunction on the effect of bipolar resistive switching in investigated structures. The inhomogeneous distribution of the electric field near the contact edge creates regions of higher electric field strength which, in turn, stimulates motion and redistribution of defects, changes of the resistive properties of the whole structure and formation of a percolation channel.

  5. Mechanism of rectification and two-type bipolar resistance switching behaviors of Pt /Pb(Zr0.52Ti0.48)O3 /Nb:SrTiO3

    NASA Astrophysics Data System (ADS)

    Liu, W. W.; Jia, C. H.; Zhang, Q.; Zhang, W. F.

    2015-12-01

    Epitaxial Pb(Zr0.52Ti0.48)O3 (PZT) films have been grown on Nb:SrTiO3 (NSTO) (1 0 0) substrates. The films are a tetragonal perovskite phase with good density and homogeneity. Rectification behavior and two types of bipolar resistance switching (BRS) have been observed in the Pt/PZT/NSTO device. It exhibits rectification below 3 V. According to piezo force microscopy analysis, PZT film has a multidomain structure below 8 V and the device shows abnormal BRS between 3 V and 8 V. When the voltage increases above 8 V, the polarization of the PZT film tends to saturation and it becomes single domain and displays normal BRS behavior. In addition, the device demonstrates good retention and anti-fatigue properties. The transition from abnormal bipolar to normal bipolar behavior caused by ferroelectric polarization can broaden device applications and enable large flexibility in terms of memory architecture.

  6. Correlations between brain structure and symptom dimensions of psychosis in schizophrenia, schizoaffective, and psychotic bipolar I disorders.

    PubMed

    Padmanabhan, Jaya L; Tandon, Neeraj; Haller, Chiara S; Mathew, Ian T; Eack, Shaun M; Clementz, Brett A; Pearlson, Godfrey D; Sweeney, John A; Tamminga, Carol A; Keshavan, Matcheri S

    2015-01-01

    Structural alterations may correlate with symptom severity in psychotic disorders, but the existing literature on this issue is heterogeneous. In addition, it is not known how cortical thickness and cortical surface area correlate with symptom dimensions of psychosis. Subjects included 455 individuals with schizophrenia, schizoaffective, or bipolar I disorders. Data were obtained as part of the Bipolar Schizophrenia Network for Intermediate Phenotypes study. Diagnosis was made through the Structured Clinical Interview for DSM-IV. Positive and negative symptom subscales were assessed using the Positive and Negative Syndrome Scale. Structural brain measurements were extracted from T1-weight structural MRIs using FreeSurfer v5.1 and were correlated with symptom subscales using partial correlations. Exploratory factor analysis was also used to identify factors among those regions correlating with symptom subscales. The positive symptom subscale correlated inversely with gray matter volume (GMV) and cortical thickness in frontal and temporal regions, whereas the negative symptom subscale correlated inversely with right frontal cortical surface area. Among regions correlating with the positive subscale, factor analysis identified four factors, including a temporal cortical thickness factor and frontal GMV factor. Among regions correlating with the negative subscale, factor analysis identified a frontal GMV-cortical surface area factor. There was no significant diagnosis by structure interactions with symptom severity. Structural measures correlate with positive and negative symptom severity in psychotic disorders. Cortical thickness demonstrated more associations with psychopathology than cortical surface area. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  7. The structure of lifetime manic-hypomanic spectrum.

    PubMed

    Cassano, G B; Mula, M; Rucci, P; Miniati, M; Frank, E; Kupfer, D J; Oppo, A; Calugi, S; Maggi, L; Gibbons, R; Fagiolini, A

    2009-01-01

    The observation that bipolar disorders frequently go unrecognized has prompted the development of screening instruments designed to improve the identification of bipolarity in clinical and non-clinical samples. Starting from a lifetime approach, researchers of the Spectrum Project developed the Mood Spectrum Self-Report (MOODS-SR) that assesses threshold-level manifestations of unipolar and bipolar mood psychopathology, but also atypical symptoms, behavioral traits and temperamental features. The aim of the present study is to examine the structure of mania/hypomania using 68 items of the MOODS-SR that explore cognitive, mood and energy/activity features associated with mania/hypomania. A data pool of 617 patients with bipolar disorders, recruited at Pittsburgh and Pisa, Italy was used for this purpose. Classical exploratory factor analysis, based on a tetrachoric matrix, was carried out on the 68 items, followed by an Item Response Theory (IRT)-based factor analytic approach. Nine factors were initially identified, that include Psychomotor Activation, Creativity, Mixed Instability, Sociability/Extraversion, Spirituality/Mysticism/Psychoticism, Mixed Irritability, Inflated Self-esteem, Euphoria, Wastefulness/Recklessness, and account overall for 56.4% of the variance of items. In a subsequent IRT-based bi-factor analysis, only five of them (Psychomotor Activation, Mixed Instability, Spirituality/Mysticism/Psychoticism, Mixed Irritability, Euphoria) were retained. Our data confirm the central role of Psychomotor Activation in mania/hypomania and support the definitions of pure manic (Psychomotor Activation and Euphoria) and mixed manic (Mixed Instability and Mixed Irritability) components, bearing the opportunity to identify patients with specific profiles for a better clinical and neurobiological definition.

  8. Symptoms of psychosis in schizophrenia, schizoaffective disorder, and bipolar disorder: A comparison of African Americans and Caucasians in the Genomic Psychiatry Cohort.

    PubMed

    Perlman, Greg; Kotov, Roman; Fu, Jinmiao; Bromet, Evelyn J; Fochtmann, Laura J; Medeiros, Helena; Pato, Michele T; Pato, Carlos N

    2016-06-01

    Several studies have reported differences between African Americans and Caucasians in relative proportion of psychotic symptoms and disorders, but whether this reflects racial bias in the assessment of psychosis is unclear. The purpose of this study was to examine the distribution of psychotic symptoms and potential bias in symptoms assessed via semi-structured interview using a cohort of 3,389 African American and 5,692 Caucasian participants who were diagnosed with schizophrenia, schizoaffective disorder, or bipolar disorder. In this cohort, the diagnosis of schizophrenia was relatively more common, and the diagnosis of bipolar disorder and schizoaffective disorder-bipolar type was less relatively common, among African Americans than Caucasians. With regard to symptoms, relatively more African Americans than Caucasians endorsed hallucinations and delusions symptoms, and this pattern was striking among cases diagnosed with bipolar disorder and schizoaffective-bipolar disorder. In contrast, the relative endorsement of psychotic symptoms was more similar among cases diagnosed with schizophrenia and schizoaffective disorder-depressed type. Differential item function analysis revealed that African Americans with mild psychosis over-endorsed "hallucinations in any modality" and under-endorsed "widespread delusions" relative to Caucasians. Other symptoms did not show evidence of racial bias. Thus, racial bias in assessment of psychotic symptoms does not appear to explain differences in the proportion of symptoms between Caucasians and African Americans. Rather, this may reflect ascertainment bias, perhaps indicative of a disparity in access to services, or differential exposure to risk factors for psychosis by race. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  9. Screening for bipolar spectrum disorders: A comprehensive meta-analysis of accuracy studies.

    PubMed

    Carvalho, André F; Takwoingi, Yemisi; Sales, Paulo Marcelo G; Soczynska, Joanna K; Köhler, Cristiano A; Freitas, Thiago H; Quevedo, João; Hyphantis, Thomas N; McIntyre, Roger S; Vieta, Eduard

    2015-02-01

    Bipolar spectrum disorders are frequently under-recognized and/or misdiagnosed in various settings. Several influential publications recommend the routine screening of bipolar disorder. A systematic review and meta-analysis of accuracy studies for the bipolar spectrum diagnostic scale (BSDS), the hypomania checklist (HCL-32) and the mood disorder questionnaire (MDQ) were performed. The Pubmed, EMBASE, Cochrane, PsycINFO and SCOPUS databases were searched. Studies were included if the accuracy properties of the screening measures were determined against a DSM or ICD-10 structured diagnostic interview. The QUADAS-2 tool was used to rate bias. Fifty three original studies met inclusion criteria (N=21,542). At recommended cutoffs, summary sensitivities were 81%, 66% and 69%, while specificities were 67%, 79% and 86% for the HCL-32, MDQ, and BSDS in psychiatric services, respectively. The HCL-32 was more accurate than the MDQ for the detection of type II bipolar disorder in mental health care centers (P=0.018). At a cutoff of 7, the MDQ had a summary sensitivity of 43% and a summary specificity of 95% for detection of bipolar disorder in primary care or general population settings. Most studies were performed in mental health care settings. Several included studies had a high risk of bias. Although accuracy properties of the three screening instruments did not consistently differ in mental health care services, the HCL-32 was more accurate than the MDQ for the detection of type II BD. More studies in other settings (for example, in primary care) are necessary. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Clinical outcomes associated with comorbid posttraumatic stress disorder among patients with bipolar disorder.

    PubMed

    Passos, Ives C; Jansen, Karen; Cardoso, Taiane de A; Colpo, Gabriela D; Zeni, Cristian P; Quevedo, Joao; Kauer-Sant'Anna, Márcia; Zunta-Soares, Giovanna; Soares, Jair C; Kapczinski, Flavio

    2016-05-01

    To assess clinical outcomes associated with the presence of a lifetime history of comorbid posttraumatic stress disorder in subjects with bipolar disorder. This cross-sectional study of 284 subjects with bipolar disorder (DSM-IV) assessed the association between lifetime comorbid posttraumatic stress disorder (DSM-IV) and clinical characteristics. Participants were included from January 2006 to June 2009. We assessed age at onset, number of mood episodes, presence of rapid cycling, first drug use, suicide attempts, hospitalizations, functional impairment, and quality of life. Diagnostic, clinical, and functional assessments were carried out using the Structured Clinical Interview for DSM-IV Axis I Disorders, patient edition (SCID-I/P), the Functioning Assessment Short Test, and the World Health Organization Quality of Life scale. The number of manic episodes as assessed by SCID-I/P was the primary outcome. The prevalence of lifetime comorbid posttraumatic stress disorder was 19.7% (56 subjects). Subjects with bipolar disorder and posttraumatic stress disorder had an accelerated course of illness, with a lower age at onset of manic/hypomanic episodes (P = .009) and earlier initiation of illicit drug use (P = .008). In addition, they were more likely to be younger when they received the diagnosis of bipolar disorder (P = .036) and had a higher number of manic/hypomanic episodes (P = .01). Quality of life was worse in all domains among subjects who presented the comorbidity, and rates of functional impairment were higher. Comorbid posttraumatic stress disorder was associated with increased morbidity and accelerated illness progression among subjects with bipolar disorder. © Copyright 2016 Physicians Postgraduate Press, Inc.

  11. Phenomenology of first-episode psychosis in schizophrenia, bipolar disorder, and unipolar depression: a comparative analysis.

    PubMed

    Rosen, Cherise; Marvin, Robert; Reilly, James L; Deleon, Ovidio; Harris, Margret S H; Keedy, Sarah K; Solari, Hugo; Weiden, Peter; Sweeney, John A

    2012-10-01

    This study sought to identify similarities and differences in symptom characteristics at initial presentation of first psychotic episodes in schizophrenia, bipolar disorder and unipolar depression. The Structured Interview for DSM-IV (SCID) and Positive and Negative Syndrome Scale (PANSS) were administered to consecutive admission study-eligible patients (n=101) presenting for treatment during their first acute phase of psychotic illness. Forty-nine percent of patients met diagnostic criteria for schizophrenia, 29% for psychotic bipolar disorder and 22% for unipolar depression with psychosis. The PANSS was analyzed using five-factor scoring that included Positive, Negative, Cognitive, Excitement, and Depression factors, and composite cluster scores that assessed Anergia, Thought Disturbance, and Paranoia. Schizophrenia and bipolar disorder patients demonstrated significantly more Positive symptoms, Thought Disturbance and Paranoia than unipolar depressed patients. Schizophrenia and unipolar depressed patients demonstrated significantly more Negative symptoms and Anergia than bipolar patients. Patients with schizophrenia reported more severe Cognitive Disorganization than patients with either bipolar disorder or uni-polar depression (p<.05). Findings from this study demonstrate an informative pattern of similarities and differences in the phenomenology of psychotic disorders at first illness presentation. Commonalities in symptom profiles reflect considerable symptom overlap among psychotic disorders and, thus, the importance of multidimensional differential diagnosis for these conditions. The differences across disorders in Positive and Negative symptom severity, Thought Disorder, Paranoia, and Anergia, and especially the higher level of Cognitive Disorganization seen in schizophrenia patients, point to clinically informative differences across these disorders that are relevant to clinical diagnostic practice and models of psychopathology.

  12. Performance of lightweight nickel electrodes

    NASA Technical Reports Server (NTRS)

    Britton, Doris L.

    1988-01-01

    The NASA Lewis Research Center is currently developing nickel electrodes for nickel-hydrogen (Ni-H2) batteries. These electrodes are lighter in weight and have higher energy densities than the heavier state-of-the-art (SOA) sintered nickel electrodes. In the present approach, lightweight materials or plaques are used as conductive supports for the nickel hydroxide active material. These plaques (fiber and felt, nickel plated plastic and graphite) are commercial products that are fabricated into nickel electrodes by electrochemically impregnating them with active material. Evaluation is performed in half cells structured in the bipolar configuration. Initial performance tests include capacity measurements at five discharge levels, C/2, 1.0C 1.37C, 2.0C and 2.74C. The electrodes that pass the initial tests are life cycle tested in a low Earth orbit regime at 80 percent depth of discharge. Different formulations of nickel fiber materials obtained from several manufacturers are currently being tested as possible candidates for nickel electrodes. One particular lightweight fiber mat electrode has accumulated over 3000 cycles to date, with stable capacity and voltage. Life and performance data of this electrode were investigated and presented. Good dimensional stability and active material adherence have been demonstrated in electrodes made from this lightweight plaque.

  13. Pediatric and adolescent anterior shoulder instability: clinical management of first-time dislocators.

    PubMed

    Lin, Kenneth M; James, Evan W; Spitzer, Elad; Fabricant, Peter D

    2018-02-01

    The purpose of this review is to discuss the epidemiology, pathoanatomy, diagnosis, and clinical management of pediatric and adolescent patients following a first-time shoulder dislocation. Shoulder instability is becoming increasingly common as pediatric and adolescent patients engage in earlier organized sports competition. Recommended treatment following a first-time glenohumeral dislocation event in adolescents depends on several factors, but surgical stabilization is becoming more frequently performed. Surgical indications include bony Bankart lesion, ALPSA lesion, bipolar injury (e.g. Hill-Sachs humeral head depression fracture) or off-season injury in an overhead or throwing athlete. Complications following surgical treatment are rare but most commonly are associated with recurrent instability. Young children (eg. open proximal humerus growth plate), individuals averse to surgery, or in-season athletes who accept the risk of redislocation may complete an accelerated rehabilitation program for expedited return to play in the absence of the structural abnormalities listed above. Following a first-time dislocation event in pediatric and adolescent patients, a detailed discussion of the risks and benefits of nonoperative versus operative management is critical to match the recommended treatment with the patient's injury pattern, risk factors, and activity goals.

  14. Structure of first- and second-stage mineralized elements in teeth of the sea urchin Lytechinus variegatus.

    PubMed

    Robach, J S; Stock, S R; Veis, A

    2009-12-01

    Microstructure of the teeth of the sea urchin Lytechinus variegatus was investigated using optical microscopy, SEM (scanning electron microscopy) and SIMS (secondary ion mass spectroscopy). The study focused on the internal structure of the first-stage mineral structures of high Mg calcite (primary, secondary and carinar process plates, prisms) and on morphology of the columns of second-stage mineral (very high Mg calcite) that cement the first-stage material together. Optical micrographs under polarized light revealed contrast in the centers (midlines) of carinar process plates and in prisms in polished sections; staining of primary and carinar process plates revealed significant dye uptake at the plate centers. Demineralization with and without fixation revealed that the midlines of primary and carinar process plates (but not secondary plates) and the centers of prisms differed from the rest of the plate or prism, and SIMS showed proteins concentrated in these plate centers. SEM was used to study the morphology of columns, the fracture surfaces of mature teeth and the 3D morphology of prisms. These observations of internal structures in plates and prisms offer new insight into the mineralization process and suggest an important role for protein inclusions within the first-stage mineral. Some of the 3D structures not reported previously, such as twisted prisms and stacks of carinar process plates with nested wrinkles, may represent structural strengthening strategies.

  15. Structure of first- and second-stage mineralized elements in teeth of the sea urchin Lytechinus variegatus

    PubMed Central

    Robach, J. S.; Stock, S. R.; Veis, A.

    2009-01-01

    Microstructure of the teeth of the sea urchin Lytechinus variegatus was investigated using optical microscopy, SEM (scanning electron microscopy) and SIMS (secondary ion mass spectroscopy). The study focused on the internal structure of the first-stage mineral structures of high Mg calcite (primary, secondary and carinar process plates; prisms) and on morphology of the columns of second-stage mineral (very high Mg calcite) that cement the first-stage material together. Optical micrographs under polarized light revealed contrast in the centers (midlines) of carinar process plates and in prisms in polished sections; staining of primary and carinar process plates revealed significant dye uptake at the plate centers. Demineralization with and without fixation revealed that the midlines of primary and carinar process plates (but not secondary plates) and the centers of prisms differed from the rest of the plate or prism, and SIMS showed proteins concentrated in these plate centers. SEM was used to study the morphology of columns, the fracture surfaces of mature teeth and the 3D morphology of prisms. These observations of internal structures in plates and prisms offer new insight into the mineralization process and suggest an important role for protein inclusions within the first-stage mineral. Some of the 3D structures not reported previously, such as twisted prisms and stacks of carinar process plates with nested wrinkles, may represent structural strengthening strategies. PMID:19616101

  16. Use of the Hypomania Checklist-32 and the Mood Disorder Questionnaire for detecting bipolarity in 1051 patients with major depressive disorder.

    PubMed

    Rybakowski, J K; Dudek, D; Pawlowski, T; Lojko, D; Siwek, M; Kiejna, A

    2012-11-01

    To use the hypomania checklist (HCL-32) and the mood disorder questionnaire (MDQ), for detecting bipolarity in depressed patients. One thousand and fifty-one patients fulfilling ICD-10 criteria for unipolar major depressive episode, single or recurrent, were studied. Patients were assessed using a structured demographic and clinical data interview, and by the Polish versions of the HCL-32 and MDQ questionnaires. Hypomanic symptoms exceeding cut-off criteria for bipolarity by HCL-32 were found in 37.5% of patients and, by MDQ, in 20% of patients. Patients with HCL-32 (+) or MDQ (+) differed significantly from patients with HCl-32 (-) and MDQ (-) respectively, by being less frequently married, having more family history of depression, bipolar disorder, alcoholism and suicide, earlier onset of illness, and more depressive episodes and psychiatric hospitalizations. The percentage of patients resistant to treatment with antidepressant drugs was significantly higher in HCL-32 (+) vs. HCL-32 (-) and in MDQ (+) vs. MDQ (-): 43.9% vs. 30.0%, and 26.4% vs. 12.4%, respectively. The results confirm a substantial percentage of bipolarity in major depressive disorder. Such patients have a number of clinical characteristics pointing on a more severe form of the illness and their depression is more resistant to treatment with antidepressants. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  17. Bipolar disorder with comorbid cluster B personality disorder features: impact on suicidality.

    PubMed

    Garno, Jessica L; Goldberg, Joseph F; Ramirez, Paul Michael; Ritzler, Barry A

    2005-03-01

    Because of their overlapping phenomenology and mutually chronic, persistent nature, distinctions between bipolar disorder and cluster B personality disorders remain a source of unresolved clinical controversy. The extent to which comorbid personality disorders impact course and outcome for bipolar patients also has received little systematic study. One hundred DSM-IV bipolar I (N = 73) or II (N = 27) patients consecutively underwent diagnostic evaluations with structured clinical interviews for DSM-IV Axis I and cluster B Axis II disorders, along with assessments of histories of childhood trauma or abuse. Cluster B diagnostic comorbidity was examined relative to lifetime substance abuse, suicide attempt histories, and other clinical features. Thirty percent of subjects met DSM-IV criteria for a cluster B personality disorder (17% borderline, 6% antisocial, 5% histrionic, 8% narcissistic). Cluster B diagnoses were significantly linked with histories of childhood emotional abuse (p = .009), physical abuse (p = .014), and emotional neglect (p = .022), but not sexual abuse or physical neglect. Cluster B comorbidity was associated with significantly more lifetime suicide attempts and current depression. Lifetime suicide attempts were significantly associated with cluster B comorbidity (OR = 3.195, 95% CI = 1.124 to 9.088), controlling for current depression severity, lifetime substance abuse, and past sexual or emotional abuse. Cluster B personality disorders are prevalent comorbid conditions identifiable in a substantial number of individuals with bipolar disorder, making an independent contribution to increased lifetime suicide risk.

  18. Nickel-metal hydride battery development. Final technical report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1995-06-01

    Rechargeable batteries are used as the power source for a broad range of portable equipment. Key battery selection criteria typically are weight, volume, first cost, life cycle cost, and environmental impact. Rechargeable batteries are favored from a life cycle cost and environmental impact standpoint over primary batteries. The nickel-metal hydride (Ni-MH) battery system has emerged as the battery of choice for many applications based on its superior characteristics when judged on the above criteria against other battery types. In most cases commercial Ni-MH batteries are constructed with coiled electrodes in cylindrical metal containers. Electro Energy, Inc. (EEI) has been developingmore » a novel flat bipolar configuration of the Ni-MH system that offers weight, volume, and cost advantages when compared to cylindrical cells. The unique bipolar approach consists of fabricating individual flat wafer cells in conductive, carbon-filled, plastic face plates. The individual cells contain a nonconductive plastic border which is heat sealed around the perimeter to make a totally sealed unit cell. Multi-cell batteries are fabricated by stacking the individual wafer cells in such a way that the positive face of one cell contacts the negative face of the adjacent cell. The stack is then contained in an outer housing with end contacts. The purpose of this program was to develop, evaluate, and demonstrate the capabilities of the EEI Ni-MH battery system for consumer applications. The work was directed at the development and evaluation of the compact bipolar construction for its potential advantages of high power and energy density. Experimental investigations were performed on various nickel electrode types, hydride electrode formulations, and alternate separator materials. Studies were also directed at evaluating various oxygen recombination techniques for low pressure operation during charge and overcharge.« less

  19. Ambient pressure fuel cell system

    DOEpatents

    Wilson, Mahlon S.

    2000-01-01

    An ambient pressure fuel cell system is provided with a fuel cell stack formed from a plurality of fuel cells having membrane/electrode assemblies (MEAs) that are hydrated with liquid water and bipolar plates with anode and cathode sides for distributing hydrogen fuel gas and water to a first side of each one of the MEAs and air with reactant oxygen gas to a second side of each one of the MEAs. A pump supplies liquid water to the fuel cells. A recirculating system may be used to return unused hydrogen fuel gas to the stack. A near-ambient pressure blower blows air through the fuel cell stack in excess of reaction stoichiometric amounts to react with the hydrogen fuel gas.

  20. Integrated main rail, feed rail, and current collector

    DOEpatents

    Petri, Randy J.; Meek, John; Bachta, Robert P.; Marianowski, Leonard G.

    1994-01-01

    A separator plate for a fuel cell comprising an anode current collector, a cathode current collector and a main plate, the main plate disposed between the anode current collector and the cathode current collector. The anode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the anode side of the separator plate and the cathode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the cathode side of the separator plate. In this manner, the number of components required to manufacture and assemble a fuel cell stack is reduced.

  1. Lossless acoustic half-bipolar cylindrical cloak with negative-index metamaterial

    NASA Astrophysics Data System (ADS)

    Lee, Yong Y.; Ahn, Doyeol

    2018-05-01

    A lossless acoustic half-bipolar cylindrical cloak that has an exposed bottom is considered. Here, we show that a cloak that includes a complementary region including a negative-index medium inside of the cloaking shell works in the illumination direction independently even in the presence of the exposed bottom of the structure. This is due to the fact that the phase velocity of the wave in the normal direction can be cancelled in the presence of a boundary containing a negative-index medium that reduces scattering significantly.

  2. The FNS-based analyzing the EEG to diagnose the bipolar affective disorder

    NASA Astrophysics Data System (ADS)

    Panischev, Yu; Panischeva, S. N.; Demin, S. A.

    2015-11-01

    Here we demonstrate a capability of method based on the Flicker-Noise Spectroscopy (FNS) in analyzing the manifestation bipolar affective disorder (BAD) in EEG. Generally EEG from BAD patient does not show the visual differences from healthy EEG. Analyzing the behavior of FNS-parameters and the structure of 3D-cross correlators allows to discover the differential characteristics of BAD. The cerebral cortex electric activity of BAD patients have a specific collective dynamics and configuration of the FNS-characteristics in comparison with healthy subjects.

  3. Improvements in Cold-Plate Fabrication

    NASA Technical Reports Server (NTRS)

    Zaffetti, Mark A.; Taddey, Edmund P.; Laurin, Michael B.; Chabebe, Natalia

    2012-01-01

    Five improvements are reported in cold-plate fabrication. This cold plate is part of a thermal control system designed to serve on space missions. The first improvement is the merging of the end sheets of the cold plate with the face sheets of the structural honeycomb panel. The cold plate, which can be a brazed assembly, uses the honeycomb face sheet as its end sheet. Thus, when the honeycomb panel is fabricated, the face sheet that is used is already part of the cold plate. In addition to reducing weight, costs, and steps, the main benefit of this invention is that it creates a more structurally sound assembly. The second improvement involves incorporation of the header into the closure bar to pass the fluid to a lower layer. Conventional designs have used a separate header, which increases the geometry of the system. The improvement reduces the geometry, thus allowing the cold plate to fit into smaller area. The third improvement eliminates the need of hose, tube, or manifold to supply the cooling fluid externally. The external arrangement can be easily damaged and is vulnerable to leakage. The new arrangement incorporates an internal fluid transfer tube. This allows the fluid to pass from one cold plate to the other without any exposed external features. The fourth improvement eliminates separate fabrication of cold plate(s) and structural members followed by a process of attaching them to each other. Here, the structural member is made of material that can be brazed just as that of the cold plate. Now the structural member and the cold plate can be brazed at the same time, creating a monolithic unit, and thus a more structurally sound assembly. Finally, the fifth improvement is the elimination of an additional welding step that can damage the braze joints. A tube section, which is usually welded on after the braze process, is replaced with a more structurally sound configuration that can be brazed at the same time as the rest of the cold plate.

  4. Power flow analysis of two coupled plates with arbitrary characteristics

    NASA Technical Reports Server (NTRS)

    Cuschieri, J. M.

    1990-01-01

    In the last progress report (Feb. 1988) some results were presented for a parametric analysis on the vibrational power flow between two coupled plate structures using the mobility power flow approach. The results reported then were for changes in the structural parameters of the two plates, but with the two plates identical in their structural characteristics. Herein, limitation is removed. The vibrational power input and output are evaluated for different values of the structural damping loss factor for the source and receiver plates. In performing this parametric analysis, the source plate characteristics are kept constant. The purpose of this parametric analysis is to determine the most critical parameters that influence the flow of vibrational power from the source plate to the receiver plate. In the case of the structural damping parametric analysis, the influence of changes in the source plate damping is also investigated. The results obtained from the mobility power flow approach are compared to results obtained using a statistical energy analysis (SEA) approach. The significance of the power flow results are discussed together with a discussion and a comparison between the SEA results and the mobility power flow results. Furthermore, the benefits derived from using the mobility power flow approach are examined.

  5. Effect of thermal stresses on frequency band structures of elastic metamaterial plates

    NASA Astrophysics Data System (ADS)

    Wu, Ying; Yu, Kaiping; Yang, Linyun; Zhao, Rui; Shi, Xiaotian; Tian, Kuo

    2018-01-01

    We investigate the effect of thermal stresses on the band structure of elastic metamaterial plates by developing a useful finite-element based method. The thermal field is assumed to be uniform throughout the whole plate. Specifically, we find that the stiffness matrix of plate element is comprised of elastic and thermal stresses parts, which can be regarded as a linear function of temperature difference. We additionally demonstrate that the relative magnitudes between elastic properties and thermal stresses will lead to nonlinear effects on frequency band structures based on two different types of metamaterial plates made of single and double inclusions of square plates, respectively. Then, we validate the proposed approach by comparing the band structures with the frequency response curves obtained in finite periodic structures. We conduct sensitivity analysis and discuss in-depth the sensitivities of band structures with respect to temperature difference to quantitatively investigate the effect of thermal stresses on each band. In addition, the coupled effects of thermal stresses and temperature-dependent material properties on the band structure of Aluminum/silicone rubber plate have also been discussed. The proposed method and new findings in this paper extends the ability of existing metamaterial plates by enabling tunability over a wide range of frequencies in thermal environments.

  6. Progression along the Bipolar Spectrum: A Longitudinal Study of Predictors of Conversion from Bipolar Spectrum Conditions to Bipolar I and II Disorders

    PubMed Central

    Alloy, Lauren B.; Urošević, Snežana; Abramson, Lyn Y.; Jager-Hyman, Shari; Nusslock, Robin; Whitehouse, Wayne G.; Hogan, Michael

    2011-01-01

    Little longitudinal research has examined progression to more severe bipolar disorders in individuals with “soft” bipolar spectrum conditions. We examine rates and predictors of progression to bipolar I and II diagnoses in a non-patient sample of college-age participants (n = 201) with high General Behavior Inventory scores and childhood or adolescent onset of “soft” bipolar spectrum disorders followed longitudinally for 4.5 years from the Longitudinal Investigation of Bipolar Spectrum (LIBS) project. Of 57 individuals with initial cyclothymia or bipolar disorder not otherwise specified (BiNOS) diagnoses, 42.1% progressed to a bipolar II diagnosis and 10.5% progressed to a bipolar I diagnosis. Of 144 individuals with initial bipolar II diagnoses, 17.4% progressed to a bipolar I diagnosis. Consistent with hypotheses derived from the clinical literature and the Behavioral Approach System (BAS) model of bipolar disorder, and controlling for relevant variables (length of follow-up, initial depressive and hypomanic symptoms, treatment-seeking, and family history), high BAS sensitivity (especially BAS Fun Seeking) predicted a greater likelihood of progression to bipolar II disorder, whereas early age of onset and high impulsivity predicted a greater likelihood of progression to bipolar I (high BAS sensitivity and Fun-Seeking also predicted progression to bipolar I when family history was not controlled). The interaction of high BAS and high Behavioral Inhibition System (BIS) sensitivities also predicted greater likelihood of progression to bipolar I. We discuss implications of the findings for the bipolar spectrum concept, the BAS model of bipolar disorder, and early intervention efforts. PMID:21668080

  7. [The concept of temperament and its contribution to the understanding of the bipolar spectrum].

    PubMed

    Koufaki, I; Polizoidou, V; Fountoulakis, K N

    2017-01-01

    The present article attempts first to provide a historical overview of the concept of temperament,The present article attempts first to provide a historical overview of the concept of temperament,since its foundation by Polybos (4th century B.C.) and the school of Cos, its predominant role in theshaping of the anthropological and humanitarian sciences, until the modern theoretical formulations,such as those proposed by Robert Cloninger and Hagop Akiskal. Secondly, recent literature ispresented, which suggests a strong link of different temperament structures to mental health andpsychopathology. Hans Eysenck (1916-1997) was the first psychologist to establish approaches topersonality differences and to distinguish three dimensions of personality: Neuroticism, Extraversionand Psychotisism. Eysenck was followed by McCrae and Costa who proposed that there are five basicdimensions of personality ("Big Five"). In the mid-1980s, Robert Cloninger developed a distinctivedimensional model of temperament and character traits. Hagop Akiskal emphasized on the affectivecomponents of temperament and their possible connections to mood disorders and creativity.Specifically, temperament assessment seems to help in differentiating between the relationship ofvarious temperaments and the clinical manifestations of bipolar illness. Within the area of mood disorders,specific affective temperaments might constitute vulnerability factors, as well as clinical pictureand illness course modifiers. Viewing mood disorders under this prism gives birth to the concept ofthe bipolar spectrum with major implications for all aspects of mental health research and providingof care. The hyperthymic and the depressive temperaments are related to the more 'classic' bipolarpicture (that is euphoria, grandiose and paranoid thinking, antisocial behavior, psychomotor accelerationand reduced sleep and depressive episodes respectively). On the contrary cyclothymic, anxiousand irritable temperaments are related to more complex pictures and might predict poor responseto treatment, violent or suicidal behavior and high comorbidity. Unipolar disorder diagnosis is oftenchanged due to the fact that a manic or mixed episode can occur after several years of treatment failure.In these cases the evaluation of temperament can prove to be effective in distinguishing betweenunipolar and bipolar depression and thus favoring treatment planning. In addition, temperament assessmentchanges the definition of bipolarity by supporting the concept of "bipolar spectrum". This isa factor that can lead to a rise in prevalence of bipolar cases. Furthermore, the evaluation of temperamenthas shifted our understanding of bipolarity towards the concept of the 'bipolar spectrum'. It hasalso led to an increase in the prevalence of bipolar disorder cases, notably bipolar II, and a decrease in unipolar cases. Finally, incorporating the concept of temperament in our understanding of bipolardisorder constitutes a challenging issue, which can lead to better treatment and outcome of patients.

  8. Comparative familial aggregation of bipolar disorder in patients with bipolar I and bipolar II disorders.

    PubMed

    Parker, Gordon B; Romano, Mia; Graham, Rebecca K; Ricciardi, Tahlia

    2018-05-01

    We sought to quantify the prevalence and differential prevalence of a bipolar disorder among family members of patients with a bipolar I or II disorder. The sample comprised 1165 bipolar and 1041 unipolar patients, with the former then sub-typed as having either a bipolar I or II condition. Family history data was obtained via an online self-report tool. Prevalence of a family member having a bipolar disorder (of either sub-type) was distinctive (36.8%). Patients with a bipolar I disorder reported a slightly higher family history (41.2%) compared to patients with a bipolar II disorder (36.3%), and with both significantly higher than the rate of bipolar disorder in family members of unipolar depressed patients (18.5%). Findings support the view that bipolar disorder is heritable. The comparable rates in the two bipolar sub-types support the positioning of bipolar II disorder as a valid condition with strong genetic underpinnings.

  9. Buckling analysis for axially compressed flat plates, structural sections, and stiffened plates reinforced with laminated composites

    NASA Technical Reports Server (NTRS)

    Viswanathan, A. V.; Soong, T.; Miller, R. E., Jr.

    1971-01-01

    A classical buckling analysis is developed for stiffened, flat plates composed of a series of linked plate and beam elements. Plates are idealized as multilayered orthotropic elements. Structural beads and lips are idealized as beams. The loaded edges of the stiffened plate are simply-supported and the conditions at the unloaded edges can be prescribed arbitrarily. The plate and beam elements are matched along their common junctions for displacement continuity and force equilibrium in an exact manner. Offsets between elements are considered in the analysis. Buckling under uniaxial compressive load for plates, sections, and stiffened plates is investigated. Buckling loads are the lowest of all possible general and local failure modes, and the mode shape is used to determine whether buckling is a local or general instability. Numerical correlations with existing analysis and test data for plates, sections, and stiffened plates including boron-reinforced structures are discussed. In general correlations are reasonably good.

  10. Discriminating Schizophrenia and Bipolar Disorder by Fusing FMRI and DTI in A Multimodal CCA+ Joint ICA Model

    PubMed Central

    Sui, Jing; Pearlson, Godfrey; Adali, Tülay; Kiehl, Kent A.; Caprihan, Arvind; Liu, Jingyu; Yamamoto, Jeremy; Calhoun, Vince D.

    2011-01-01

    Diverse structural and functional brain alterations have been identified in both schizophrenia and bipolar disorder, but with variable replicability, significant overlap and often in limited number of subjects. In this paper, we aimed to clarify differences between bipolar disorder and schizophrenia by combining fMRI (collected during an auditory oddball task) and diffusion tensor imaging (DTI) data. We proposed a fusion method, “multimodal CCA+ joint ICA’, which increases flexibility in statistical assumptions beyond existing approaches and can achieve higher estimation accuracy. The data collected from 164 participants (62 healthy controls, 54 schizophrenia and 48 bipolar) were extracted into “features” (contrast maps for fMRI and fractional anisotropy (FA) for DTI) and analyzed in multiple facets to investigate the group differences for each pair-wised groups and each modality. Specifically, both patient groups shared significant dysfunction in dorsolateral prefrontal cortex and thalamus, as well as reduced white matter (WM) integrity in anterior thalamic radiation and uncinate fasciculus. Schizophrenia and bipolar subjects were separated by functional differences in medial frontal and visual cortex, as well as WM tracts associated with occipital and frontal lobes. Both patients and controls showed similar spatial distributions in motor and parietal regions, but exhibited significant variations in temporal lobe. Furthermore, there were different group trends for age effects on loading parameters in motor cortex and multiple WM regions, suggesting brain dysfunction and WM disruptions occurred in identified regions for both disorders. Most importantly, we can visualize an underlying function-structure network by evaluating the joint components with strong links between DTI and fMRI. Our findings suggest that although the two patient groups showed several distinct brain patterns from each other and healthy controls, they also shared common abnormalities in prefrontal thalamic WM integrity and in frontal brain mechanisms. PMID:21640835

  11. Mobility power flow analysis of an L-shaped plate structure subjected to acoustic excitation

    NASA Technical Reports Server (NTRS)

    Cuschieri, J. M.

    1989-01-01

    An analytical investigation based on the Mobility Power Flow method is presented for the determination of the vibrational response and power flow for two coupled flat plate structures in an L-shaped configuration, subjected to acoustical excitation. The principle of the mobility power flow method consists of dividing the global structure into a series of subsystems coupled together using mobility functions. Each separate subsystem is analyzed independently to determine the structural mobility functions for the junction and excitation locations. The mobility functions, together with the characteristics of the junction between the subsystems, are then used to determine the response of the global structure and the power flow. In the coupled plate structure considered here, mobility power flow expressions are derived for excitation by an incident acoustic plane wave. In this case, the forces (acoustic pressures) acting on the structure are dependent on the response of the structure because of the scattered pressure component. The interaction between the structure and the fluid leads to the derivation of a corrected mode shape for the plates' normal surface velocity and also for the structure mobility functions. The determination of the scattered pressure components in the expressions for the power flow represents an additional component in the power flow balance for the source plate and the receiver plate. This component represents the radiated acoustical power from the plate structure.

  12. Association between history of psychosis and cardiovascular disease in bipolar disorder.

    PubMed

    Prieto, Miguel L; McElroy, Susan L; Hayes, Sharonne N; Sutor, Bruce; Kung, Simon; Bobo, William V; Fuentes, Manuel E; Cuellar-Barboza, Alfredo B; Crow, Scott; Ösby, Urban; Chauhan, Mohit; Westman, Jeanette; Geske, Jennifer R; Colby, Colin L; Ryu, Euijung; Biernacka, Joanna M; Frye, Mark A

    2015-08-01

    To determine whether clinical features of bipolar disorder, such as history of psychosis, and cardiovascular disease (CVD) risk factors contribute to a higher risk of CVD among patients with bipolar disorder. This cross-sectional study included a sample of 988 patients with bipolar I or bipolar II disorder or schizoaffective bipolar type confirmed by the Structured Clinical Interview for DSM-IV-TR disorders (SCID). Medical comorbidity burden was quantified utilizing the Cumulative Illness Severity Rating Scale (CIRS). This 13-item organ-based scale includes cardiac disease severity quantification. Confirmed by medical record review, patients who scored 1 (current mild or past significant problem) or higher in the cardiac item were compared by logistic regression to patients who scored 0 (no impairment), adjusting for CVD risk factors that were selected using a backwards stepwise approach or were obtained from the literature. In a multivariate model, age [odds ratio (OR) = 3.03, 95% confidence interval (CI): 1.66-5.54, p < 0.0001], hypertension (OR = 2.43, 95% CI: 1.69-3.55, p < 0.0001), and history of psychosis (OR = 1.48, 95% CI: 1.03-2.13, p = 0.03) were associated with CVD. When CVD risk factors from the literature were added to the analysis, age (OR = 3.19, 95% CI: 1.67-6.10, p = 0.0005) and hypertension (OR = 2.46, 95% CI: 1.61-3.76, p < 0.01) remained significant, with psychosis being at the trend level (OR = 1.43, 95% CI: 0.96-2.13, p = 0.08). The phenotype of psychotic bipolar disorder may reflect higher illness severity with associated cardiac comorbidity. Further studies are encouraged to clarify the effect of the disease burden (i.e., depression), lifestyle, and treatment interventions (i.e., atypical antipsychotics) on this risk association. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Reliability and validity of TEMPS-A in a Japanese non-clinical population: application to unipolar and bipolar depressives.

    PubMed

    Matsumoto, Satoko; Akiyama, Tsuyoshi; Tsuda, Hitoshi; Miyake, Yuko; Kawamura, Yoshiya; Noda, Toshie; Akiskal, Kareen K; Akiskal, Hagop S

    2005-03-01

    In Japan, TEMPS-A has gathered much attention, because Kraepelin's concepts on "fundamental states" of mood disorder and temperaments have been widely respected. TEMPS-A was translated into Japanese (and after the approval of the English back translation by H.S.A.), it was administered to 1391 non-clinical subjects, and 29 unipolar and 30 bipolar patients in remission. Of the non-clinical sample, 426 were readministered the instrument again in 1 month. A control group matched for gender and age was drawn from the non-clinical sample. Regarding test-retest reliability, Spearman's coefficients for depressive, cyclothymic, hyperthymic, irritable and anxious temperaments were 0.79, 0.84, 0.87, 0.81 and 0.87, respectively; regarding internal consistency, Cronbach's alpha coefficients were 0.69, 0.84, 0.79, 0.83 and 0.87, respectively. The unipolar and bipolar groups showed significantly higher depressive, cyclothymic and anxious temperament scores than the control group. Curiously, the bipolar group showed significantly lower hyperthymic score than the control group; irritable temperament scores showed no significant differences. Depressive, cyclothymic, irritable and anxious temperament scores showed significant correlations with each other. Between the unipolar and bipolar groups, there was little difference regarding the temperament scores. Also the inter-temperament correlations showed the same pattern in the unipolar and bipolar groups. The clinically well cohort was 70% male. TEMPS-A showed a high reliability and validity (internal consistency) in a Japanese non-clinical sample. By and large, the hypothesized five temperament structure was upheld. Depressive, cyclothymic and anxious temperaments showed concurrent validity with mood disorder. Irritable temperament may represent a subtype of depressive, cyclothymic or anxious temperaments. There may be a temperamental commonality between unipolar and bipolar disorders. TEMPS-A will open new possibilities for international research on mood disorder and personality traits.

  14. High-performance silicon nanowire bipolar phototransistors

    NASA Astrophysics Data System (ADS)

    Tan, Siew Li; Zhao, Xingyan; Chen, Kaixiang; Crozier, Kenneth B.; Dan, Yaping

    2016-07-01

    Silicon nanowires (SiNWs) have emerged as sensitive absorbing materials for photodetection at wavelengths ranging from ultraviolet (UV) to the near infrared. Most of the reports on SiNW photodetectors are based on photoconductor, photodiode, or field-effect transistor device structures. These SiNW devices each have their own advantages and trade-offs in optical gain, response time, operating voltage, and dark current noise. Here, we report on the experimental realization of single SiNW bipolar phototransistors on silicon-on-insulator substrates. Our SiNW devices are based on bipolar transistor structures with an optically injected base region and are fabricated using CMOS-compatible processes. The experimentally measured optoelectronic characteristics of the SiNW phototransistors are in good agreement with simulation results. The SiNW phototransistors exhibit significantly enhanced response to UV and visible light, compared with typical Si p-i-n photodiodes. The near infrared responsivities of the SiNW phototransistors are comparable to those of Si avalanche photodiodes but are achieved at much lower operating voltages. Compared with other reported SiNW photodetectors as well as conventional bulk Si photodiodes and phototransistors, the SiNW phototransistors in this work demonstrate the combined advantages of high gain, high photoresponse, low dark current, and low operating voltage.

  15. Effects of cutouts on the behavior of symmetric composite laminates subjected to bending and twisting loads

    NASA Technical Reports Server (NTRS)

    Prasad, C. B.; Shuart, M. J.; Bains, N. J.; Rouse, M.

    1993-01-01

    Composite structures are used for a wide variety of aerospace applications. Practical structures contain cutouts and these structures are subjected to in-plane and out-of-plane loading conditions. Structurally efficient designs for composite structures require a thorough understanding of the effects of cutouts on the response of composite plates subjected to inplane or out-of-plane loadings. Most investigations of the behavior of composite plates with cutouts have considered in-plane loadings only. Out-of-plane loadings suchas bending or twisting have received very limited attention. The response of homogeneous plates (e.g., isotropic or orthotropic plates) subjected to bending or twisting moments has been studied analytically. These analyses are for infinite plates and neglect finite-plate effects. Recently, analytical and experimental studies were conducted to determine the effects of cutouts on the response of laminated composite plates subjected to bending moments. No analytical or experimental results are currently available for the effects of cutouts on the response of composite laminates subjected to twisting moments.

  16. Internal electrolyte supply system for reliable transport throughout fuel cell stacks

    DOEpatents

    Wright, Maynard K.; Downs, Robert E.; King, Robert B.

    1988-01-01

    An improved internal electrolyte supply system in a fuel cell stack employs a variety of arrangements of grooves and passages in bipolar plates of the multiplicity of repeating fuel cells to route gravity-assisted flowing electrolyte throughout the stack. The grooves route electrolyte flow along series of first paths which extend horizontally through the cells between the plates thereof. The passages route electrolyte flow along series of second paths which extend vertically through the stack so as to supply electrolyte to the first paths in order to expose the electrolyte to the matrices of the cells. Five different embodiments of the supply system are disclosed. Some embodiments employ wicks in the grooves for facilitating transfer of the electrolyte to the matrices as well as providing support for the matrices. Additionally, the passages of some embodiments by-pass certain of the grooves and supply electrolyte directly to other of the grooves. Some embodiments employ single grooves and others have dual grooves. Finally, in some embodiments the passages are connected to the grooves by a step which produces a cascading electrolyte flow.

  17. Structural Inference in the Art of Violin Making.

    NASA Astrophysics Data System (ADS)

    Morse-Fortier, Leonard Joseph

    The "secrets" of success of early Italian violins have long been sought. Among their many efforts to reproduce the results of Stradiveri, Guarneri, and Amati, luthiers have attempted to order and match natural resonant frequencies in the free violin plates. This tap-tone plate tuning technique is simply an eigenvalue extraction scheme. In the final stages of carving, the violin maker complements considerable intuitive knowledge of violin plate structure and of modal attributes with tap-tone frequency estimates to better understand plate structure and to inform decisions about plate carving and completeness. Examining the modal attributes of violin plates, this work develops and incorporates an impulse-response scheme for modal inference, measures resonant frequencies and modeshapes for a pair of violin plates, and presents modeshapes through a unique computer visualization scheme developed specifically for this purpose. The work explores, through simple examples questions of how plate modal attributes reflect underlying structure, and questions about the so -called evolution of modeshapes and frequencies through assembly of the violin. Separately, the work develops computer code for a carved, anisotropic, plate/shell finite element. Solutions are found to the static displacement and free-vibration eigenvalue problems for an orthotropic plate, and used to verify element accuracy. Finally, a violin back plate is modelled with full consideration of plate thickness and arching. Model estimates for modal attributes compare very well against experimentally acquired values. Finally, the modal synthesis technique is applied to predicting the modal attributes of the violin top plate with ribs attached from those of the top plate alone, and with an estimate of rib mass and stiffness. This last analysis serves to verify the modal synthesis method, and to quantify its limits of applicability in attempting to solve problems with severe structural modification. Conclusions emphasize the importance of better understanding the underlying structure, improved understanding of its relationship to modal attributes, and better estimates of wood elasticity.

  18. Coexistence of bipolar and unipolar resistive switching behaviors in the double-layer Ag/ZnS-Ag/CuAlO2/Pt memory device

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Xu, Haiyang; Wang, Zhongqiang; Yu, Hao; Ma, Jiangang; Liu, Yichun

    2016-01-01

    The coexistence of uniform bipolar and unipolar resistive-switching (RS) characteristics was demonstrated in a double-layer Ag/ZnS-Ag/CuAlO2/Pt memory device. By changing the compliance current (CC) from 1 mA to 10 mA, the RS behavior can be converted from the bipolar mode (BRS) to the unipolar mode (URS). The temperature dependence of low resistance states further indicates that the CFs are composed of the Ag atoms and Cu vacancies for the BRS mode and URS mode, respectively. For this double-layer structure device, the thicker conducting filaments (CFs) will be formed in the ZnS-Ag layer, and it can act as tip electrodes. Thus, the formation and rupture of these two different CFs are located in the CuAlO2 layer, realizing the uniform and stable BRS and URS.

  19. Two novel blue phosphorescent host materials containing phenothiazine-5,5-dioxide structure derivatives

    PubMed Central

    Xie, Feng-Ming; Ou, Qingdong; Zhang, Qiang; Zhang, Jiang-Kun; Dai, Guo-Liang

    2018-01-01

    Two novel D–A bipolar blue phosphorescent host materials based on phenothiazine-5,5-dioxide: 3-(9H-carbazol-9-yl)-10-ethyl-10H-phenothiazine-5,5-dioxide (CEPDO) and 10-butyl-3-(9H-carbazol-9-yl)-10H-phenothiazine-5,5-dioxide (CBPDO) were synthesized and characterized. The photophysical, electrochemical and thermal properties were systematically investigated. CEPDO and CBPDO not only have a high triplet energy but also show a bipolar behavior. Moreover, their fluorescence emission peaks are in the blue fluorescence region at 408 nm and the fluorescence quantum efficiency (Φ) of CEPDO and CBPDO were 62.5% and 59.7%, respectively. Both CEPDO and CBPDO showed very high thermal stability with decomposition temperatures (T d) of 409 and 396 °C as well as suitable HOMO and LUMO energy levels. This preferable performance suggests that CEPDO and CBPDO are alternative bipolar host materials for the PhOLEDs. PMID:29765467

  20. Relationship Between Temperament and Character Traits, Mood, and Medications in Bipolar I Disorder.

    PubMed

    Chavez, Sergio B; Alvarado, Luis A; Gonzalez, Robert

    2016-01-01

    Bipolar I disorder is an illness causing mood shifts that can result in personality and character trait alterations. The relationship between mood and personality and character traits in bipolar I disorder is unclear at this time. We conducted a study from February 2009 to March 2010 that included 42 subjects with bipolar I disorder, which was confirmed using the Structured Clinical Interview for DSM-IV Axis I Disorders. Mood was assessed via the Young Mania Rating Scale (YMRS) and the 30-item Clinician-rated Inventory of Depressive Symptomatology (IDS-C). Temperament and character traits were assessed via the Temperament and Character Inventory (TCI). Multivariate analysis was used to test relationships between mood and temperament and character traits with the effects of possible cofactors taken into account (eg, age, gender, medications). We noted a positive correlation between YMRS scores and persistence ( P = .046) and a trend toward positive correlation with novelty seeking ( P = .054). There was a positive correlation between higher IDS-C scores and harm avoidance ( P < .001) and a negative correlation with self-directedness scores ( P < .001). Antipsychotic use was positively correlated with the character trait self-directedness ( P = .008), with a trend toward a positive correlation with reward dependence ( P = .056). Lithium was negatively correlated with reward dependence ( P = .047) and self-transcendence ( P = .028), with a trend toward a negative correlation with novelty seeking ( P = .053). The findings of our study suggest that some personality and character traits may vary according to mood state and medications in patients with bipolar I disorder. Prospective and longitudinal studies are required to fully characterize the relationships between personality and character traits and mood state in bipolar I disorder.

  1. Altered affective, executive and sensorimotor resting state networks in patients with pediatric mania

    PubMed Central

    Wu, Minjie; Lu, Lisa H.; Passarotti, Alessandra M.; Wegbreit, Ezra; Fitzgerald, Jacklynn; Pavuluri, Mani N.

    2013-01-01

    Background The aim of the present study was to map the pathophysiology of resting state functional connectivity accompanying structural and functional abnormalities in children with bipolar disorder. Methods Children with bipolar disorder and demographically matched healthy controls underwent resting-state functional magnetic resonance imaging. A model-free independent component analysis was performed to identify intrinsically interconnected networks. Results We included 34 children with bipolar disorder and 40 controls in our analysis. Three distinct resting state networks corresponding to affective, executive and sensorimotor functions emerged as being significantly different between the pediatric bipolar disorder (PBD) and control groups. All 3 networks showed hyperconnectivity in the PBD relative to the control group. Specifically, the connectivity of the dorsal anterior cingulate cortex (ACC) differentiated the PBD from the control group in both the affective and the executive networks. Exploratory analysis suggests that greater connectivity of the right amygdala within the affective network is associated with better executive function in children with bipolar disorder, but not in controls. Limitations Unique clinical characteristics of the study sample allowed us to evaluate the pathophysiology of resting state connectivity at an early state of PBD, which led to the lack of generalizability in terms of comorbid disorders existing in a typical PBD population. Conclusion Abnormally engaged resting state affective, executive and sensorimotor networks observed in children with bipolar disorder may reflect a biological context in which abnormal task-based brain activity can occur. Dual engagement of the dorsal ACC in affective and executive networks supports the neuroanatomical interface of these networks, and the amygdala’s engagement in moderating executive function illustrates the intricate interplay of these neural operations at rest. PMID:23735583

  2. The role of life events and psychological factors in the onset of first and recurrent mood episodes in bipolar offspring: results from the Dutch Bipolar Offspring Study.

    PubMed

    Kemner, S M; Mesman, E; Nolen, W A; Eijckemans, M J C; Hillegers, M H J

    2015-01-01

    Life events are an established risk factor for the onset and recurrence of unipolar and bipolar mood episodes, especially in the presence of genetic vulnerability. The dynamic interplay between life events and psychological context, however, is less studied. In this study, we investigated the impact of life events on the onset and recurrence of mood episodes in bipolar offspring, as well as the effects of temperament, coping and parenting style on this association. Bipolar offspring (n = 108) were followed longitudinally from adolescence to adulthood. Mood disorders were assessed with: the Kiddie Schedule of Affective Disorders and Schizophrenia - Present and Lifetime Version or the Structured Clinical Interview for DSM-IV Axis I disorders; life events with the Life Events and Difficulties Schedule; and psychological measures using the Utrecht Coping List, Temperament and Character Inventory and short-EMBU (memories of upbringing instrument). Anderson-Gill models (an extension of the Cox proportional hazard model) were utilized. Life events were associated with an increased risk for first and, although less pronounced, subsequent mood episodes. There was a large confounding effect for the number of previous mood episodes; findings suggest a possible kindling effect. Passive coping style increased the risk of mood episode onset and recurrent episodes, but also altered the effect of life events on mood disorders. Harm avoidance temperament was associated with mood episode recurrence. Life events are especially a risk factor in the onset of mood disorders, though less so in recurrent episodes. Psychological features (passive coping and harm-avoidant temperament) contribute to the risk of an episode occurring, and also have a moderating effect on the association between life events and mood episodes. These findings create potential early intervention strategies for bipolar offspring.

  3. Integrated main rail, feed rail, and current collector

    DOEpatents

    Petri, R.J.; Meek, J.; Bachta, R.P.; Marianowski, L.G.

    1994-11-08

    A separator plate is described for a fuel cell comprising an anode current collector, a cathode current collector and a main plate, the main plate disposed between the anode current collector and the cathode current collector. The anode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the anode side of the separator plate and the cathode current collector forms a flattened peripheral wet seal structure and manifold wet seal structure on the cathode side of the separator plate. In this manner, the number of components required to manufacture and assemble a fuel cell stack is reduced. 9 figs.

  4. Hierarchical personality traits and the distinction between unipolar and bipolar disorders.

    PubMed

    Quilty, Lena C; Pelletier, Marianne; Deyoung, Colin G; Michael Bagby, R

    2013-05-01

    The association between personality and psychopathology can provide an insight into the structure of mental disorders and the shared etiology and pathophysiology underlying diagnoses with overlapping symptomatology. The majority of personality-psychopathology research pertinent to the mood disorders has focused upon traits at the higher-order levels of the personality hierarchy, rather than those at intermediate or lower levels. The purpose of the current investigation was to investigate whether unipolar and bipolar mood disorders, and the severity of depressive and manic symptoms, show differential associations with traits at multiple levels of the personality hierarchy. Participants (N=275; 63% women; mean age 42.95 years) with depressive disorders (n=139) and bipolar disorders (n=136), as assessed by the Structured Clinical Interview for DSM-IV, Axis I Disorders, Patient Version (SCID-I/P; First et al., 1995), completed the Hamilton Depression Rating Scale, Young Mania Scale, Revised NEO Personality Inventory and Big Five Aspect Scales. Results support the hypothesis that lower levels of the personality hierarchy provide additional differentiation of affective pathology. As compared to the widespread association of depressive symptoms with traits across the personality hierarchy, manic symptoms demonstrated more specific associations with traits at lower levels of the personality hierarchy. Patients with severe mania were excluded, thus the full range of mania is not represented in the current sample. These results support the use of lower-order personality traits to discriminate between unipolar versus bipolar mood disorder, and are consistent with changes proposed to the psychiatric nosology to increase diagnostic precision. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. European Network of Bipolar Research Expert Centre (ENBREC): a network to foster research and promote innovative care.

    PubMed

    Henry, Chantal; Andreassen, Ole A; Barbato, Angelo; Demotes-Mainard, Jacques; Goodwin, Guy; Leboyer, Marion; Vieta, Eduard; Nolen, Willem A; Kessing, Lars Vedel; Scott, Jan; Bauer, Michael

    2013-01-01

    Bipolar disorders rank as one of the most disabling illnesses in working age adults worldwide. Despite this, the quality of care offered to patients with this disorder is suboptimal, largely due to limitations in our understanding of the pathology. Improving this scenario requires the development of a critical mass of expertise and multicentre collaborative projects. Within the framework of the European FP7 programme, we developed a European Network of Bipolar Research Expert Centres (ENBREC) designed specifically to facilitate EU-wide studies. ENBREC provides an integrated support structure facilitating research on disease mechanisms and clinical outcomes across six European countries (France, Germany, Italy, Norway, Spain and the UK). The centres are adopting a standardised clinical assessment that explores multiple aspects of bipolar disorder through a structured evaluation designed to inform clinical decision-making as well as being applicable to research. Reliable, established measures have been prioritised, and instruments have been translated and validated when necessary. An electronic healthcare record and monitoring system (e-ENBREC©) has been developed to collate the data. Protocols to conduct multicentre clinical observational studies and joint studies on cognitive function, biomarkers, genetics, and neuroimaging are in progress; a pilot study has been completed on strategies for routine implementation of psycho-education. The network demonstrates 'proof of principle' that expert centres across Europe can collaborate on a wide range of basic science and clinical programmes using shared protocols. This paper is to describe the network and how it aims to improve the quality and effectiveness of research in a neglected priority area.

  6. Experimental investigation on the dynamic response of clamped corrugated sandwich plates subjected to underwater impulsive loadings

    NASA Astrophysics Data System (ADS)

    Huang, Wei; Zhang, Wei; Li, Dacheng; Hypervelocity Impact Research Center Team

    2015-06-01

    Corrugated sandwich plates are widely used in marine industry because such plates have high strength-to-weight ratios and blast resistance. The laboratory-scaled fluid-structure interaction experiments are performed to demonstrate the shock resistance of solid monolithic plates and corrugated sandwich plates by quantifying the permanent transverse deflection at mid-span of the plates as a function of impulsive loadings per areal mass. Sandwich structures with 6mm-thick and 10mm-thick 3003 aluminum corrugated core and 5A06 face sheets are compared with the 5A06 solid monolithic plates in this paper. The dynamic deformation of plates are captured with the the 3D digital speckle correlation method (DIC). The results affirm that sandwich structures show a 30% reduction in the maximum plate deflection compare with a monolithic plate of identical mass per unit area, and the peak value of deflection effectively reduced by increasing the thickness core. The failure modes of sandwich plates consists of core crushing, imprinting, stretch tearing of face sheets, bending and permanent deformation of entire structure with the increasing impulsive loads, and the failure mechanisms are analyzed with the postmortem panels and dynamic deflection history captured by cameras. National Natural Science Foundation of China (NO.: 11372088).

  7. From bipolar to quadrupolar - The collimation processes of the Cepheus A outflow

    NASA Technical Reports Server (NTRS)

    Torrelles, Jose M.; Verdes-Montenegro, Lourdes; Ho, Paul T. P.; Rodriguez, Luis F.; Canto, Jorge

    1993-01-01

    Results of new K-band observations of the (1, 1) and (2, 2) ammonia lines toward Cepheus A are reported. The lines are mapped with approximately 2 arcsec of angular resolution and 0.3 km/s of velocity resolution. A sensitivity of 10 mJy has been achieved. The observations reveal details of the spatial and kinematics structure of the ambient high-density gas. It is suggested that the interstellar high-density gas is diverting and redirecting the outflow in the sense that the quadrupolar structure of the molecular outflow is produced by the interaction with the ammonia condensationss, with Cep A-1 and Cep A-3 splitting in two halves, respectively the blue- and redshifted lobes of an east-west bipolar molecular outflow.

  8. Analysis of improved dc and ac performances of an InGaP/GaAs heterojunction bipolar transistor with a graded Al xGa 1- xAs layer at emitter/base heterojunction

    NASA Astrophysics Data System (ADS)

    Cheng, Shiou-Ying

    2004-07-01

    An InGaP/GaAs heterojunction bipolar transistor (HBT) with a continuous conduction-band structure is demonstrated and theoretically investigated. This device exhibited good performance including lower turn-on voltage, lower offset voltage and smaller collector current saturation voltage. The novel aspect of device structure design is the adoption of the compositionally linear-graded AlGaAs layer between the InGaP-emitter and GaAs-base layers. Therefore, the device studied shows better dc and ac performances than a conventional device. Consequently, this causes the substantial benefit for practical analog and digital applications especially for lower operation voltage, lower power consumption commercial and military products.

  9. Neuropsychological and neuroimaging underpinnings of schizoaffective disorder: a systematic review.

    PubMed

    Madre, M; Canales-Rodríguez, E J; Ortiz-Gil, J; Murru, A; Torrent, C; Bramon, E; Perez, V; Orth, M; Brambilla, P; Vieta, E; Amann, B L

    2016-07-01

    The neurobiological basis and nosological status of schizoaffective disorder remains elusive and controversial. This study provides a systematic review of neurocognitive and neuroimaging findings in the disorder. A comprehensive literature search was conducted via PubMed, ScienceDirect, Scopus and Web of Knowledge (from 1949 to 31st March 2015) using the keyword 'schizoaffective disorder' and any of the following terms: 'neuropsychology', 'cognition', 'structural neuroimaging', 'functional neuroimaging', 'multimodal', 'DTI' and 'VBM'. Only studies that explicitly examined a well defined sample, or subsample, of patients with schizoaffective disorder were included. Twenty-two of 43 neuropsychological and 19 of 51 neuroimaging articles fulfilled inclusion criteria. We found a general trend towards schizophrenia and schizoaffective disorder being related to worse cognitive performance than bipolar disorder. Grey matter volume loss in schizoaffective disorder is also more comparable to schizophrenia than to bipolar disorder which seems consistent across further neuroimaging techniques. Neurocognitive and neuroimaging abnormalities in schizoaffective disorder resemble more schizophrenia than bipolar disorder. This is suggestive for schizoaffective disorder being a subtype of schizophrenia or being part of the continuum spectrum model of psychosis, with schizoaffective disorder being more skewed towards schizophrenia than bipolar disorder. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. The process of recovery from bipolar I disorder: a qualitative analysis of personal accounts in relation to an integrative cognitive model.

    PubMed

    Mansell, Warren; Powell, Seth; Pedley, Rebecca; Thomas, Nia; Jones, Sarah Amelia

    2010-06-01

    This study explored the process of recovery from bipolar I disorder from a phenomenological and cognitive perspective. A semi-structured interview was coded and analysed using interpretative phenomenological analysis. Eleven individuals over the age of 30 with a history of bipolar disorder were selected on the basis of having remained free from relapse, and without hospitalization for at least 2 years, as confirmed by a diagnostic interview (Standardised Interview for DSM-IV; SCID-I). This arbitrary and equivocal criterion for 'recovery' provided an objective method of defining the sample for the study. The analysis revealed two overarching themes formed from four themes each. Ambivalent approaches referred to approaches that participants felt had both positive and negative consequences: avoidance of mania, taking medication, prior illness versus current wellness, and sense of identity following diagnosis. Helpful approaches referred to approaches that were seen as universally helpful: understanding, life-style fundamentals, social support and companionship, and social change. These themes were then interpreted in the light of the existing literature and an integrative cognitive model of bipolar disorder. Limitations and future research directions are discussed.

  11. Obsessive-compulsive disorder with and without bipolar disorder.

    PubMed

    Mahasuar, Rajnarayan; Janardhan Reddy, Y C; Math, Suresh Bada

    2011-08-01

    Bipolar disorder (BD) is often comorbid with obsessive-compulsive disorder (OCD). In this study, we compared clinical profile and course of subjects with a primary diagnosis of OCD with and without BD. We compared 34 subjects with primary diagnosis of OCD with BD and 57 subjects with a diagnosis of OCD without BD. Structured interview schedules, clinical rating scales, and information from clinical charts were utilized to assess patients. OCD with BD was characterized by: (i) an episodic course; (ii) a higher number of depressive episodes, greater suicidality and a higher rate of hospitalization; (iii) fewer pathological doubts and more miscellaneous compulsions; and (iv) poorer insight into obsessive-compulsive symptoms. Episodic course appears to be typical of OCD with BD. Bipolarity has a pathoplastic effect on OCD and it is possible that some forms of OCD and BD are pathophysiologically related. Bipolar OCD is associated with a higher rate of depressive episodes, higher suicidality and more frequent hospitalizations, suggesting greater morbidity. Long-term prospective follow-up studies and studies addressing pathophysiology and genetic basis are needed to understand the complexity of such comorbidity. © 2011 The Authors. Psychiatry and Clinical Neurosciences © 2011 Japanese Society of Psychiatry and Neurology.

  12. Evidence for a bipolar change in distortion product otoacoustic emissions during contralateral acoustic stimulation in humans

    NASA Astrophysics Data System (ADS)

    Müller, Jörg; Janssen, Thomas; Heppelmann, Guido; Wagner, Wolfgang

    2005-12-01

    The aim of this study was to investigate the activity of the medial olivocochlear (MOC) efferents during contralateral (CAS) and ipsilateral acoustic stimulation (IAS) by recording distortion product otoacoustic emission (DPOAE) suppression and DPOAE adaptation in humans. The main question was: do large bipolar changes in DPOAE level (transition from enhancement to suppression) also occur in humans when changing the primary tone level within a small range as described by Maison and Liberman for guinea pigs [J. Neurosci. 20, 4701-4707 (2000)]? In the present study, large bipolar changes in DPOAE level (14 dB on average across subjects) were found during CAS predominantly at frequencies where dips in the DPOAE fine structure occurred. Thus, effects of the second DPOAE source might be responsible for the observed bipolar effect. In contrast, comparable effects were not found during IAS as was reported in guinea pigs. Reproducibility of CAS DPOAEs was better than that for IAS DPOAEs. Thus, contralateral DPOAE suppression is suggested to be superior to ipsilateral DPOAE adaptation with regard to measuring the MOC reflex strength and for evaluating the vulnerability of the cochlea to acoustic overexposure in a clinical context.

  13. Buckling analysis for structural sections and stiffened plates reinforced with laminated composites.

    NASA Technical Reports Server (NTRS)

    Viswanathan, A. V.; Soong, T.-C.; Miller, R. E., Jr.

    1972-01-01

    A classical buckling analysis is developed for stiffened, flat plates composed of a series of linked flat plate and beam elements. Plates are idealized as multilayered orthotropic elements; structural beads and lips are idealized as beams. The loaded edges of the stiffened plate are simply supported and the conditions at the unloaded edges can be prescribed arbitrarily. The plate and beam elements are matched along their common junctions for displacement continuity and force equilibrium in an exact manner. Offsets between elements are considered in the analysis. Buckling under uniaxial compressive load for plates, sections and stiffened plates is investigated. Buckling loads are found as the lowest of all possible general and local failure modes and the mode shape is used to determine whether buckling is a local or general instability. Numerical correlations with existing analysis and test data for plates, sections and stiffened plates including boron-reinforced structures are discussed. In general, correlations are reasonably good.

  14. Belief Structures about People Held by Selected Graduate Students.

    ERIC Educational Resources Information Center

    Dole, Arthur A.; And Others

    Wrightsman has established that assumptions about human nature distinguish religious, occupational, political, gender, and other groups, and that they predict behavior in structured situations. Hjelle and Ziegler proposed a set of nine basic bipolar assumptions about the nature of people: freedom-determinism; rationality-irrationality;…

  15. Influence of the wavelet order on proper damage location in plate structures

    NASA Astrophysics Data System (ADS)

    Pawlak, Zdzisław; Knitter-Piątkowska, Anna

    2018-01-01

    The rectangular thin plates were analyzed in the paper. The static response in plate structure subjected to the uniform load was derived by applying the finite element method. In the dynamic, experimental tests the accelerations were obtained with the use of modal hammer and DEWEsoft® software. Next, the analysis of the signal was carried out with the use of Discrete Wavelet Transform (DWT), provided that damage exists in the considered plate structure. It was assumed, that in the middle of the structure a certain area of the plate is thinner or there is a crack across the entire plate thickness. The aim of this work was to choose the appropriate wavelet order to reveal the localization of defect. The results of selected numerical example proved the efficiency of proposed approach.

  16. Confirming the structure of negative beliefs about psychosis and bipolar disorder: A confirmatory factor analysis study of the Personal Beliefs about Experience Questionnaire and Personal Beliefs about Illness Questionnaire.

    PubMed

    Taylor, Peter J; Pyle, Melissa; Schwannauer, Matthias; Hutton, Paul; Morrison, Anthony

    2015-11-01

    Negative beliefs about psychosis and other mental health difficulties may contribute to depression and distress in individuals with these experiences. The Personal Beliefs about Experience Questionnaire (PBEQ) and Personal Beliefs about Illness Questionnaire (PBIllQ) are two widely used measures of these beliefs. It is currently uncertain how the items on these measures map onto different underlying factors. This study therefore aimed to test the factor structure of these two measures. Confirmatory factor analysis (CFA) was used to test three alternative, pre-specified, factor structures for the PBIllQ and PBEQ in a sample of individuals diagnosed with bipolar disorder (n = 202) and a sample of individuals with experien-ces of psychosis (n = 362). Associations with depressive symptoms were also examined. A three-factor structure was supported for both measures, which included Negative Expectations/Appraisals (NEA), Internal Shame/Defectiveness (ISD) and External Shame (ES) factors. The NEA and ISD subscales also had consistent independent associations with depressive symptoms. The results suggest that the PBIllQ and PBEQ may capture three distinct sets of negative beliefs in individuals with psychosis or bipolar disorder and that these beliefs may have important consequences for subsequent difficulties in these populations such as depression. Both measures may be helpful in supporting assessment and formulation in clinical practice and in evaluating belief change in intervention trials. However, when used in these settings, the three subscales identified in this study may be the most valid way of calculating scores on these measures. Negative personal beliefs about the causes, meaning and consequences of psychosis and bipolar disorder are associated with greater distress and depression. Two related measures, the PBIllQ and PBEQ, have been developed to assess these beliefs. Our analyses suggest that scores on these questionnaires are best broken down into three subscales which capture perceptions of internal shame or defectiveness, general negative appraisals and perceptions of external shame. These subscales may capture key underlying sets of negative beliefs within individuals with psychosis or bipolar disorder, which in turn impact upon well-being, such as being associated with greater depression. These subscales can be used to aid assessment and formulation within clinical practice but may also provide a valuable means of assessing changes in negative beliefs following interventions. © 2015 The British Psychological Society.

  17. The application of PA/CF in stab resistance body armor

    NASA Astrophysics Data System (ADS)

    Yuan, M. Q.; Liu, Y.; Gong, Z.; Qian, X. M.

    2017-06-01

    Stab resistance body armor (SRBA) is an essential defensive equipment to protect human body against injuries from stabbing. The conventional SRBAs shared low wearing frequency since they are heavy and poor in flexibility. This paper designed a structured stab-resistance plate using the model of crocodile armor and manufactured using 3D printing technology-laser sintering (LS). CF(Carbon fiber) was applied to enhance the stab resistance properties of SRBA. The effects of the material and structure were analysed through the stab resistance property tests based on the national standard GA68-2008. It is found that the stab resistance property of flat plates sintered by PA powder and PA/CF are both weaker than that of the structured plate. The penetrating depth of PA/CF structured plate is significantly 2-mm-less than the pure PA structured plate. The SEM observations confirmed the conclusion that addition of the CF largely improved the plate stab resistance property. Moreover, using PA/CF structured plate to produce the stab resistance body armor would result in a weight reduction by about 30-40% as compared to the existing SRBA that was made up of metal plates, which could largely reduce the wearer physical burden and improve the wearing frequency.

  18. A Butterfly in the Making: Revealing the Near-Infrared Structure of Hubble 12

    NASA Technical Reports Server (NTRS)

    Hora, Joseph L.; Latter, William B.

    1996-01-01

    We present deep narrowband near-IR images and moderate resolution spectra of the young planetary nebula Hubble 12. These data are the first to show clearly the complex structure for this important planetary nebula. Images were obtained at lambda = 2.12, 2.16, and 2.26 micron. The lambda = 2.12 Am image reveals the bipolar nature of the nebula, as well as complex structure near the central star in the equatorial region. The images show an elliptical region of emission, which may indicate a ring or a cylindrical source structure. This structure is possibly related to the mechanism that is producing the bipolar flow. The spectra show the nature of several distinct components. The central object is dominated by recombination lines of H I and He I. The core is not a significant source of molecular hydrogen emission. The east position in the equatorial region is rich in lines of ultraviolet-excited fluorescent H2. A spectrum of part of the central region shows strong [Fe II] emission, which might indicate the presence of shocks.

  19. The loss of the kinases SadA and SadB results in early neuronal apoptosis and a reduced number of progenitors.

    PubMed

    Dhumale, Pratibha; Menon, Sindhu; Chiang, Joanna; Püschel, Andreas W

    2018-01-01

    The neurons that form the mammalian neocortex originate from progenitor cells in the ventricular (VZ) and subventricular zone (SVZ). Newborn neurons are multipolar but become bipolar during their migration from the germinal layers to the cortical plate (CP) by forming a leading process and an axon that extends in the intermediate zone (IZ). Once they settle in the CP, neurons assume a highly polarized morphology with a single axon and multiple dendrites. The AMPK-related kinases SadA and SadB are intrinsic factors that are essential for axon formation during neuronal development downstream of Lkb1. The knockout of both genes encoding Sad kinases (Sada and Sadb) results not only in a loss of axons but also a decrease in the size of the cortical plate. The defect in axon formation has been linked to a function of Sad kinases in the regulation of microtubule binding proteins. However, the causes for the reduced size of the cortical plate in the Sada-/-;Sadb-/- knockout remain to be analyzed in detail. Here we show that neuronal cell death is increased and the number of neural progenitors is decreased in the Sada-/-;Sadb-/- CP. The reduced number of progenitors is a non-cell autonomous defect since they do not express Sad kinases. These defects are restricted to the neocortex while the hippocampus remains unaffected.

  20. Method of producing exfoliated graphite composite compositions for fuel cell flow field plates

    DOEpatents

    Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z

    2014-04-08

    A method of producing an electrically conductive composite composition, which is particularly useful for fuel cell bipolar plate applications. The method comprises: (a) providing a supply of expandable graphite powder; (b) providing a supply of a non-expandable powder component comprising a binder or matrix material; (c) blending the expandable graphite with the non-expandable powder component to form a powder mixture wherein the non-expandable powder component is in the amount of between 3% and 60% by weight based on the total weight of the powder mixture; (d) exposing the powder mixture to a temperature sufficient for exfoliating the expandable graphite to obtain a compressible mixture comprising expanded graphite worms and the non-expandable component; (e) compressing the compressible mixture at a pressure within the range of from about 5 psi to about 50,000 psi in predetermined directions into predetermined forms of cohered graphite composite compact; and (f) treating the so-formed cohered graphite composite to activate the binder or matrix material thereby promoting adhesion within the compact to produce the desired composite composition. Preferably, the non-expandable powder component further comprises an isotropy-promoting agent such as non-expandable graphite particles. Further preferably, step (e) comprises compressing the mixture in at least two directions. The method leads to composite plates with exceptionally high thickness-direction electrical conductivity.

  1. Integral field spectroscopy of M1-67. A Wolf-Rayet nebula with luminous blue variable nebula appearance

    NASA Astrophysics Data System (ADS)

    Fernández-Martín, A.; Vílchez, J. M.; Pérez-Montero, E.; Candian, A.; Sánchez, S. F.; Martín-Gordón, D.; Riera, A.

    2013-06-01

    Aims: This work aims to disentangle the morphological, kinematic, and chemical components of the nebula M1-67 to shed light on its process of formation around the central Wolf-Rayet (WR) star WR124. Methods: We have carried out integral field spectroscopy observations over two regions of M1-67, covering most of the nebula in the optical range. Maps of electron density, line ratios, and radial velocity were created to perform a detailed analysis of the two-dimensional structure. We studied the physical and chemical properties by means of integrated spectra selected over the whole nebula. Photoionization models were performed to confirm the empirical chemical results theoretically. In addition, we obtained and analysed infrared spectroscopic data and the MIPS 24 μm image of M1-67 from Spitzer. Results: We find that the ionized gas of M1-67 is condensed in knots aligned in a preferred axis along the NE-SW direction, like a bipolar structure. Both electron density and radial velocity decrease in this direction when moving away from the central star. From the derived electron temperature, Te ~ 8200 K, we have estimated chemical abundances, obtaining that nitrogen appears strongly enriched and oxygen depleted. From the last two results, we infer that this bipolarity is the consequence of an ejection of an evolved stage of WR124 with material processed in the CNO cycle. Furthermore, we find two regions placed outside of the bipolar structure with different spectral and chemical properties. The infrared study has revealed that the bipolar axis is composed of ionized gas with a low ionization degree that is well mixed with warm dust and of a spherical bubble surrounding the ejection at 24 μm. Taking the evolution of a 60 M⊙ star and the temporal scale of the bipolar ejection into account, we propose that the observed gas was ejected during an eruption in the luminous blue variable stage. The star has entered the WR phase recently without apparent signs of interaction between WR-winds and interstellar material. Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck-Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC).

  2. Bipolar Disorder in Nursing Homes: Impact on Antipsychotic Use, Diagnosis Patterns, and New Diagnoses in People with Dementia.

    PubMed

    Carnahan, Ryan M; Letuchy, Elena M

    2018-01-01

    Nursing home quality measures include the proportion of residents who receive antipsychotics. Residents with bipolar disorder are included even though antipsychotics are FDA-approved for this indication. We evaluated how including residents with bipolar disorder impacted the antipsychotic use quality measure for long-stay residents. We evaluated the agreement of minimum data set (MDS) bipolar disorder diagnoses with Medicare data, whether dementia was diagnosed before bipolar disorder, and how less-specific bipolar disorder diagnoses impacted findings. Cross-sectional study. Nursing homes in Iowa. 21,955 long-stay nursing home residents in the first quarter of 2014. We identified antipsychotic use and bipolar disorder using MDS data. We compared MDS bipolar disorder diagnoses with Chronic Conditions Warehouse (CCW) "ever" bipolar disorder indicators, and prior year claims. We compared CCW condition onset dates to identify bipolar disorder diagnosed after dementia. The mean (SD) proportion receiving antipsychotics was 19.6% (11.1%) with bipolar disorder and 18.3% (10.8%) without. The positive predictive value (PPV) of MDS bipolar disorder diagnoses was 80.2% versus CCW lifetime indicators, and 74.6% versus claims. PPV decreased by 27.1% when "bipolar disorder, unspecified" and "other bipolar disorders" diagnoses were excluded. Nearly three-quarters of residents with bipolar disorder had dementia. Over half of those with dementia had dementia first per CCW records. This proportion was lower among those with more specific bipolar disorder diagnoses or MDS bipolar disorder indicators. Bipolar disorder in nursing home residents is often first diagnosed after dementia using nonspecific diagnoses. This practice deserves further evaluation. Copyright © 2017 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  3. Factor structure of cognition and functional capacity in two studies of schizophrenia and bipolar disorder: Implications for genomic studies.

    PubMed

    Harvey, Philip D; Aslan, Mihaela; Du, Mengtian; Zhao, Hongyu; Siever, Larry J; Pulver, Ann; Gaziano, J Michael; Concato, John

    2016-01-01

    Impairments in cognition and everyday functioning are common in schizophrenia and bipolar disorder (BPD). In this article, we present factor analyses of cognitive and functional capacity (FC) measures based on 2 studies of schizophrenia (SCZ) and bipolar I disorder (BPI) using similar methods. The overall goal of these analyses was to determine whether performance-based assessments should be examined individually, or aggregated on the basis of the correlational structure of the tests, as well as to evaluate the similarity of factor structures of SCZ and BPI. Veterans Affairs Cooperative Studies Program Study #572 (Harvey et al., 2014) evaluated cognitive and FC measures among 5,414 BPI and 3,942 SCZ patients. A 2nd study evaluated similar neuropsychological (NP) and FC measures among 368 BPI and 436 SCZ patients. Principal components analysis, as well as exploratory and CFAs, were used to examine the data. Analyses in both datasets suggested that NP and FC measures were explained by a single underlying factor in BPI and SCZ patients, both when analyzed separately or as in a combined sample. The factor structure in both studies was similar, with or without inclusion of FC measures; homogeneous loadings were observed for that single factor across cognitive and FC domains across the samples. The empirically derived factor model suggests that NP performance and FC are best explained as a single latent trait applicable to people with SCZ and BPD. This single measure may enhance the robustness of the analyses relating genomic data to performance-based phenotypes. (c) 2015 APA, all rights reserved).

  4. Characterisation of structure-borne sound source using reception plate method.

    PubMed

    Putra, A; Saari, N F; Bakri, H; Ramlan, R; Dan, R M

    2013-01-01

    A laboratory-based experiment procedure of reception plate method for structure-borne sound source characterisation is reported in this paper. The method uses the assumption that the input power from the source installed on the plate is equal to the power dissipated by the plate. In this experiment, rectangular plates having high and low mobility relative to that of the source were used as the reception plates and a small electric fan motor was acting as the structure-borne source. The data representing the source characteristics, namely, the free velocity and the source mobility, were obtained and compared with those from direct measurement. Assumptions and constraints employing this method are discussed.

  5. The Effect of Structural Curvings on the Stress Distribution in a Rigidly Fixed Composite Plate under Forced Vibration

    NASA Astrophysics Data System (ADS)

    Zamanov, A. D.

    2002-01-01

    Based on the exact three-dimensional equations of continuum mechanics and the Akbarov-Guz' continuum theory, the problem on forced vibrations of a rectangular plate made of a composite material with a periodically curved structure is formulated. The plate is rigidly fixed along the Ox 1 axis. Using the semi-analytic method of finite elements, a numerical procedure is elaborated for investigating this problem. The numerical results on the effect of structural curvings on the stress distribution in the plate under forced vibrations are analyzed. It is shown that the disturbances of the stress σ22 in a hinge-supported plate are greater than in a rigidly fixed one. Also, it is found that the structural curvings considerably affect the stress distribution in plates both under static and dynamic loading.

  6. Passive control of coherent structures in a modified backwards-facing step flow

    NASA Astrophysics Data System (ADS)

    Ormonde, Pedro C.; Cavalieri, André V. G.; Silva, Roberto G. A. da; Avelar, Ana C.

    2018-05-01

    We study a modified backwards-facing step flow, with the addition of two different plates; one is a baseline, impermeable plate and the second a perforated one. An experimental investigation is carried out for a turbulent reattaching shear layer downstream of the two plates. The proposed setup is a model configuration to study how the plate characteristics affect the separated shear layer and how turbulent kinetic energies and large-scale coherent structures are modified. Measurements show that the perforated plate changes the mean flow field, mostly by reducing the intensity of reverse flow close to the bottom wall. Disturbance amplitudes are significantly reduced up to five step heights downstream of the trailing edge of the plate, more specifically in the recirculation region. A loudspeaker is then used to introduce phase-locked, low-amplitude perturbations upstream of the plates, and phase-averaged measurements allow a quantitative study of large-scale structures in the shear-layer. The evolution of such coherent structures is evaluated in light of linear stability theory, comparing the eigenfunction of the Kelvin-Helmholtz mode to the experimental results. We observe a close match of linear-stability eigenfunctions with phase-averaged amplitudes for the two tested Strouhal numbers. The perforated plate is found to reduce the amplitude of the Kelvin-Helmholtz coherent structures in comparison to the baseline, impermeable plate, a behavior consistent with the predicted amplification trends from linear stability.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Elizondo-Decanini, Juan M.

    Short pulse neutron generators are described herein. In a general embodiment, the short pulse neutron generator includes a Blumlein structure. The Blumlein structure includes a first conductive plate, a second conductive plate, a third conductive plate, at least one of an inductor or a resistor, a switch, and a dielectric material. The first conductive plate is positioned relative to the second conductive plate such that a gap separates these plates. A vacuum chamber is positioned in the gap, and an ion source is positioned to emit ions in the vacuum chamber. The third conductive plate is electrically grounded, and themore » switch is operable to electrically connect and disconnect the second conductive plate and the third conductive plate. The at least one of the resistor or the inductor is coupled to the first conductive plate and the second conductive plate.« less

  8. Algae inhibition experiment and load characteristics of the algae solution

    NASA Astrophysics Data System (ADS)

    Xiong, L.; Gao, J. X.; Zhang, Y. X.; Yang, Z. K.; Zhang, D. Q.; He, W.

    2016-08-01

    It is necessary to inhibit microbial growth in an industrial cooling water system. This paper has developed a Monopolar/Bipolar polarity high voltage pulser with load adaptability for an algal experimental study. The load characteristics of the Chlorella pyrenoidosa solution were examined, and it was found that the solution load is resistive. The resistance is related to the plate area, concentration, and temperature of the solution. Furthermore, the pulser's treatment actually inhibits the algae cell growth. This article also explores the influence of various parameters of electric pulses on the algal effect. After the experiment, the optimum pulse parameters were determined to be an electric field intensity of 750 V/cm, a pulse width per second of 120μs, and monopolar polarity.

  9. [Differential diagnosis between dissociative disorders and schizophrenia].

    PubMed

    Shibayama, Masatoshi

    2011-01-01

    The differential diagnosis of dissociative disorders includes many psychiatric disorders, such as schizophrenia, bipolar disorders (especially bipolar II disorder), depressive disorder (especially atypical depression), epilepsy, Asperger syndrome, and borderline personality disorder. The theme of this paper is the differential diagnosis between dissociative disorders and schizophrenia. Schneiderian first-rank symptoms in schizophrenia are common in dissociative disorders, especially in dissociative identity disorder (DID). Many DID patients have been misdiagnosed as schizophrenics and treated with neuroleptics. We compared and examined Schneiderian symptoms of schizophrenia and those of dissociative disorders from a structural viewpoint. In dissociative disorders, delusional perception and somatic passivity are not seen. "Lateness" and "Precedence of the Other" originated from the concept of "Pattern Reversal" (H. Yasunaga)" is characteristic of schizophrenia. It is important to check these basic structure of schizophrenia in subjective experiences in differential diagnosis between dissociative disorders and schizophrenia.

  10. Compact, Two-Sided Structural Cold Plate Configuration

    NASA Technical Reports Server (NTRS)

    Zaffetti, Mark

    2011-01-01

    In two-sided structural cold plates, typically there is a structural member, such as a honeycomb panel, that provides the structural strength for the cold plates that cool equipment. The cold plates are located on either side of the structural member and thus need to have the cooling fluid supplied to them. One method of accomplishing this is to route the inlet and outlet tubing to both sides of the structural member. Another method might be to supply the inlet to one side and the outlet to the other. With the latter method, an external feature such as a hose, tube, or manifold must be incorporated to pass the fluid from one side of the structural member to the other. Although this is a more compact design than the first option, since it eliminates the need for a dedicated supply and return line to each side of the structural member, it still poses problems, as these external features can be easily damaged and are now new areas for potential fluid leakage. This invention eliminates the need for an external feature and instead incorporates the feature internally to the structural member. This is accomplished by utilizing a threaded insert that not only connects the cold plate to the structural member, but also allows the cooling fluid to flow through it into the structural member, and then to the cold plate on the opposite side. The insert also employs a cap that acts as a cover to seal the open area needed to install the insert. There are multiple options for location of o-ring style seals, as well as the option to use adhesive for redundant sealing. Another option is to weld the cap to the cold plate after its installation, thus making it an integral part of the structural member. This new configuration allows the fluid to pass from one cold plate to the other without any exposed external features.

  11. Six years of evidence-based adult dissection tonsillectomy with ultrasonic scalpel, bipolar electrocautery, bipolar radiofrequency or 'cold steel' dissection.

    PubMed

    Ragab, S M

    2012-10-01

    To conduct an adequately powered, prospective, randomised, controlled trial comparing adult dissection tonsillectomy using either ultrasonic scalpel, bipolar electrocautery, bipolar radiofrequency or 'cold steel' dissection. Three hundred patients were randomised into four tonsillectomy technique groups. The operative time, intra-operative bleeding, post-operative pain, tonsillar fossa healing, return to full diet, return to work and post-operative complications were recorded. The bipolar radiofrequency group had a shorter mean operative time. The mean intra-operative blood loss during bipolar radiofrequency tonsillectomy was significantly less compared with cold dissection and ultrasonic scalpel tonsillectomy. Pain scores were significantly higher after bipolar electrocautery tonsillectomy. Patients undergoing bipolar electrocautery tonsillectomy required significantly more days to return to full diet and work. The bipolar electrocautery group showed significantly reduced tonsillar fossa healing during the first and second post-operative weeks. In this adult series, bipolar radiofrequency tonsillectomy was superior to ultrasonic, bipolar electrocautery and cold dissection tonsillectomies. This method combines the advantages of 'hot' and 'cold' tonsillectomy.

  12. Dynamic Stiffness Modeling of Composite Plate and Shell Assemblies

    DTIC Science & Technology

    2013-12-09

    FA8655-10-1-3084 Report 6 Dynamic Stiffness Modelling of Plate and Shell Assemblies 4 Introduction Aerospace structures are generally made up of thin ...Sound and Vibration, 294(1- 2):131–161, 2006. [23] Y. F. Xing and B. Liu. New exact solutions for free vibrations of thin orthotropic rectangular plates ...Structures, 89(5–6):467–475, 2011. [80] A.Y.T. Leung. Dynamic stiffness analysis of laminated composite plates . Thin - Walled Structures, 25:109–133, 1996

  13. Lightweight structure design for supporting plate of primary mirror

    NASA Astrophysics Data System (ADS)

    Wang, Xiao; Wang, Wei; Liu, Bei; Qu, Yan Jun; Li, Xu Peng

    2017-10-01

    A topological optimization design for the lightweight technology of supporting plate of the primary mirror is presented in this paper. The supporting plate of the primary mirror is topologically optimized under the condition of determined shape, loads and environment. And the optimal structure is obtained. The diameter of the primary mirror in this paper is 450mm, and the material is SiC1 . It is better to select SiC/Al as the supporting material. Six points of axial relative displacement can be used as constraints in optimization2 . Establishing the supporting plate model and setting up the model parameters. After analyzing the force of the main mirror on the supporting plate, the model is applied with force and constraints. Modal analysis and static analysis of supporting plates are calculated. The continuum structure topological optimization mathematical model is created with the variable-density method. The maximum deformation of the surface of supporting plate under the gravity of the mirror and the first model frequency are assigned to response variable, and the entire volume of supporting structure is converted to object function. The structures before and after optimization are analyzed using the finite element method. Results show that the optimized fundamental frequency increases 29.85Hz and has a less displacement compared with the traditional structure.

  14. Hydrodynamics of a flexible plate between pitching rigid plates

    NASA Astrophysics Data System (ADS)

    Kim, Junyoung; Kim, Daegyoum

    2017-11-01

    The dynamics of a flexible plate have been studied as a model problem in swimming and flying of animals and fluid-structure interaction of plants and flags. Motivated by fish schooling and an array of sea grasses, we investigate the dynamics of a flexible plate closely placed between two pitching rigid plates. In most studies on passive deformation of the flexible plate, the plate is immersed in a uniform flow or a wavy flow. However, in this study, the flexible plate experiences periodic deformation by the oscillatory flow generated by the prescribed pitching motion of the rigid plates. In our model, the pitching axes of the rigid plates and the clamping position of the flexible plate are aligned on the same line. The flexible plate shows various responses depending on length and pitching frequency of rigid plates, thickness of a flexible plate, and free-stream velocity. To find the effect of each variable on the response of the flexible plate, amplitude of a trailing edge and modal contribution of a flapping motion are compared, and flow structure around the flexible plate is examined.

  15. Ultrahigh resolution radiation imaging system using an optical fiber structure scintillator plate.

    PubMed

    Yamamoto, Seiichi; Kamada, Kei; Yoshikawa, Akira

    2018-02-16

    High resolution imaging of radiation is required for such radioisotope distribution measurements as alpha particle detection in nuclear facilities or high energy physics experiments. For this purpose, we developed an ultrahigh resolution radiation imaging system using an optical fiber structure scintillator plate. We used a ~1-μm diameter fiber structured GdAlO 3 :Ce (GAP) /α-Al 2 O 3 scintillator plate to reduce the light spread. The fiber structured scintillator plate was optically coupled to a tapered optical fiber plate to magnify the image and combined with a lens-based high sensitivity CCD camera. We observed the images of alpha particles with a spatial resolution of ~25 μm. For the beta particles, the images had various shapes, and the trajectories of the electrons were clearly observed in the images. For the gamma photons, the images also had various shapes, and the trajectories of the secondary electrons were observed in some of the images. These results show that combining an optical fiber structure scintillator plate with a tapered optical fiber plate and a high sensitivity CCD camera achieved ultrahigh resolution and is a promising method to observe the images of the interactions of radiation in a scintillator.

  16. Lasting mantle scars lead to perennial plate tectonics.

    PubMed

    Heron, Philip J; Pysklywec, Russell N; Stephenson, Randell

    2016-06-10

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a 'perennial' phenomenon.

  17. Lasting mantle scars lead to perennial plate tectonics

    PubMed Central

    Heron, Philip J.; Pysklywec, Russell N.; Stephenson, Randell

    2016-01-01

    Mid-ocean ridges, transform faults, subduction and continental collisions form the conventional theory of plate tectonics to explain non-rigid behaviour at plate boundaries. However, the theory does not explain directly the processes involved in intraplate deformation and seismicity. Recently, damage structures in the lithosphere have been linked to the origin of plate tectonics. Despite seismological imaging suggesting that inherited mantle lithosphere heterogeneities are ubiquitous, their plate tectonic role is rarely considered. Here we show that deep lithospheric anomalies can dominate shallow geological features in activating tectonics in plate interiors. In numerical experiments, we found that structures frozen into the mantle lithosphere through plate tectonic processes can behave as quasi-plate boundaries reactivated under far-field compressional forcing. Intraplate locations where proto-lithospheric plates have been scarred by earlier suturing could be regions where latent plate boundaries remain, and where plate tectonics processes are expressed as a ‘perennial' phenomenon. PMID:27282541

  18. Determining if Borderline Personality Disorder and Bipolar Disorder Are Alternative Expressions of the Same Disorder: Results From the National Epidemiologic Survey on Alcohol and Related Conditions.

    PubMed

    de la Rosa, Iris; Oquendo, María A; García, Gemma; Stanley, Barbara; González-Pinto, Ana; Liu, Shang-Min; Blanco, Carlos

    To examine whether bipolar disorder and borderline personality disorder represent 2 different disorders or alternative manifestations of the same disorder. The data were collected between January 1, 2004, and December 31, 2005. The analyses were conducted between December 21 and December 27, 2010. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed on 25 symptoms assessing depression, mania, and borderline personality disorder from the National Epidemiologic Survey on Alcohol and Related Conditions, a large nationally representative sample of the US adult population (N = 34,653). DSM-IV criteria were used for diagnosis of bipolar disorder and borderline personality disorder. A 3-factor solution provided an excellent fit in both the EFA (root mean square error of approximation [RMSEA] = 0.017, comparative fix index [CFI] = 0.997) and the CFA (RMSEA = 0.024, CFI = 0.993). Factor 1 (Borderline Personality Disorder) loaded on all 9 borderline personality disorder symptoms, factor 2 (Depression) loaded on 8 symptoms of depression, and factor 3 (Mania) loaded on 7 symptoms of mania plus the psychomotor agitation item of the depression section. The correlations between the Borderline Personality Disorder and Depression factors (r = 0.328) and between the Borderline Personality Disorder and Mania factors (r = 0.394) were lower than the correlation between Depression and Mania factors (r = 0.538). A model with 3 positively correlated factors provided an excellent fit for the latent structure of borderline personality disorder and bipolar disorder symptoms. The pattern of pairwise correlations between the 3 factors is consistent with the clinical presentation of 2 syndromes (depression and mania) that can be characterized as a unitary psychiatric entity (bipolar disorder) and a third syndrome (borderline personality disorder) that is often comorbid with bipolar disorder. The findings converge in suggesting that bipolar disorder and borderline personality disorder are overlapping but different pathologies. These findings may serve to inform ongoing efforts to refine the existing psychiatric nosology and to suggest new avenues for etiologic and treatment research. © Copyright 2017 Physicians Postgraduate Press, Inc.

  19. Bipolar Spintronics: From magnetic diodes to magnetic bipolar transistors

    NASA Astrophysics Data System (ADS)

    Zutic, Igor

    2004-03-01

    We develop a theory of bipolar (electrons and holes) spin-polarized transport [1,2] in semiconductors and discuss its implications for spintronic devices [3]. In our proposal for magnetic bipolar transistors [4,5] we show how bipolar spintronics can lead to spin and magnetic field controlled active devices, not limited by the magnetoresistive effects used in all-metallic structures [3]. We focus on magnetic p-n diodes [1,2] with spatially dependent spin splitting (Zeeman or exchange) of carrier bands. An exchange splitting can be provided by ferromagnetic semiconductors [6], while a large Zeeman splitting can be realized in the presence of magnetic field in magnetically doped or narrow band gap semiconductors [3]. Our theory of magnetic diodes [1,2] can be directly applied to magnetic bipolar transistors--the three-terminal devices which consist of two magnetic p-n diodes connected in series [4,5]. Predictions of exponentially large magnetoresistance [1] and a strong coupling between the spin and charge transport leading to the spin-voltaic effect [1,7] for magnetic diodes are also relevant for magnetic bipolar transistors. In particular, in n-p-n transistors, we show the importance of considering the nonequilibrium spin leading to the spin-voltaic effect. In addition to the applied magnetic filed, the injected nonequilibrium spin can be used to dynamically control the current amplification (gain). Recent experimental progress [8,9] supports the viability of our theoretical proposals. [1] I. Zutic, J. Fabian, S. Das Sarma, Phys. Rev. Lett. 88, 066603 (2002). [2] J. Fabian, I. Zutic, S. Das Sarma, Phys. Rev. B 66, 165301 (2002). [3] I. Zutic, J. Fabian, S. Das Sarma, Rev. Mod. Phys., in press. [4] J. Fabian, I. Zutic, S. Das Sarma, cond-mat/0211639; cond-mat/0307014, Appl. Phys. Lett., in press. [5] J. Fabian and I. Zutic, cond-mat/0311456. [6] H. Ohno, Science 281, 951 (1998). [7] I. Zutic, J. Fabian, S. Das Sarma, Appl. Phys. Lett. 82, 221 (2003). [8] N. Samarth, S. H. Chun, K. C. Ku, S. J. Potashnik, P. Schiffer, Solid State Commun. 127, 173 (2003). [9] F. Tsui, L. Ma, L. He, Appl. Phys. 83, 954 (2003).

  20. Staging in bipolar disorder: from theoretical framework to clinical utility

    PubMed Central

    Berk, Michael; Post, Robert; Ratheesh, Aswin; Gliddon, Emma; Singh, Ajeet; Vieta, Eduard; Carvalho, Andre F.; Ashton, Melanie M.; Berk, Lesley; Cotton, Susan M.; McGorry, Patrick D.; Fernandes, Brisa S.; Yatham, Lakshmi N.; Dodd, Seetal

    2017-01-01

    Illness staging is widely utilized in several medical disciplines to help predict course or prognosis, and optimize treatment. Staging models in psychiatry in general, and bipolar disorder in particular, depend on the premise that psychopathology moves along a predictable path: an at‐risk or latency stage, a prodrome progressing to a first clinical threshold episode, and one or more recurrences with the potential to revert or progress to late or end‐stage manifestations. The utility and validity of a staging model for bipolar disorder depend on its linking to clinical outcome, treatment response and neurobiological measures. These include progressive biochemical, neuroimaging and cognitive changes, and potentially stage‐specific differences in response to pharmacological and psychosocial treatments. Mechanistically, staging models imply the presence of an active disease process that, if not remediated, can lead to neuroprogression, a more malignant disease course and functional deterioration. Biological elements thought to be operative in bipolar disorder include a genetic diathesis, physical and psychic trauma, epigenetic changes, altered neurogenesis and apoptosis, mitochondrial dysfunction, inflammation, and oxidative stress. Many available agents, such as lithium, have effects on these targets. Staging models also suggest the utility of stage‐specific treatment approaches that may not only target symptom reduction, but also impede illness neuroprogression. These treatment approaches range from prevention for at‐risk individuals, to early intervention strategies for prodromal and newly diagnosed individuals, complex combination therapy for rapidly recurrent illness, and palliative‐type approaches for those at chronic, late stages of illness. There is hope that prompt initiation of potentially disease modifying therapies may preclude or attenuate the cognitive and structural changes seen in the later stages of bipolar disorder. The aims of this paper are to: a) explore the current level of evidence supporting the descriptive staging of the syndromal pattern of bipolar disorder; b) describe preliminary attempts at validation; c) make recommendations for the direction of further studies; and d) provide a distillation of the potential clinical implications of staging in bipolar disorder within a broader transdiagnostic framework. PMID:28941093

  1. Staging in bipolar disorder: from theoretical framework to clinical utility.

    PubMed

    Berk, Michael; Post, Robert; Ratheesh, Aswin; Gliddon, Emma; Singh, Ajeet; Vieta, Eduard; Carvalho, Andre F; Ashton, Melanie M; Berk, Lesley; Cotton, Susan M; McGorry, Patrick D; Fernandes, Brisa S; Yatham, Lakshmi N; Dodd, Seetal

    2017-10-01

    Illness staging is widely utilized in several medical disciplines to help predict course or prognosis, and optimize treatment. Staging models in psychiatry in general, and bipolar disorder in particular, depend on the premise that psychopathology moves along a predictable path: an at-risk or latency stage, a prodrome progressing to a first clinical threshold episode, and one or more recurrences with the potential to revert or progress to late or end-stage manifestations. The utility and validity of a staging model for bipolar disorder depend on its linking to clinical outcome, treatment response and neurobiological measures. These include progressive biochemical, neuroimaging and cognitive changes, and potentially stage-specific differences in response to pharmacological and psychosocial treatments. Mechanistically, staging models imply the presence of an active disease process that, if not remediated, can lead to neuroprogression, a more malignant disease course and functional deterioration. Biological elements thought to be operative in bipolar disorder include a genetic diathesis, physical and psychic trauma, epigenetic changes, altered neurogenesis and apoptosis, mitochondrial dysfunction, inflammation, and oxidative stress. Many available agents, such as lithium, have effects on these targets. Staging models also suggest the utility of stage-specific treatment approaches that may not only target symptom reduction, but also impede illness neuroprogression. These treatment approaches range from prevention for at-risk individuals, to early intervention strategies for prodromal and newly diagnosed individuals, complex combination therapy for rapidly recurrent illness, and palliative-type approaches for those at chronic, late stages of illness. There is hope that prompt initiation of potentially disease modifying therapies may preclude or attenuate the cognitive and structural changes seen in the later stages of bipolar disorder. The aims of this paper are to: a) explore the current level of evidence supporting the descriptive staging of the syndromal pattern of bipolar disorder; b) describe preliminary attempts at validation; c) make recommendations for the direction of further studies; and d) provide a distillation of the potential clinical implications of staging in bipolar disorder within a broader transdiagnostic framework. © 2017 World Psychiatric Association.

  2. Delusional Themes Across Affective and Non-Affective Psychoses

    PubMed Central

    Picardi, Angelo; Fonzi, Laura; Pallagrosi, Mauro; Gigantesco, Antonella; Biondi, Massimo

    2018-01-01

    The current debate about the diagnostic significance of delusion revolves around two positions. The neurocognitive position conceives delusion as a non-specific, though polymorphic, symptom. The psychopathological position views features of delusion such as content and structure as having meaningful connections with diagnostic entities. This study aims at contributing to this debate by examining the association between delusional themes and diagnosis in a sample of 830 adult psychotic patients. All diagnoses were made by experienced psychiatrists according to DSM-IV or ICD-10 criteria, and in 348 patients were established with the SCID-I. All patients were administered the Brief Psychiatric Rating Scale (BPRS). In each patient, the presence of somatic delusions and delusions of guilt, grandiosity, and persecution was determined by examining the scores on relevant BPRS items. Delusions of guilt were almost pathognomonic for a psychotic depressive condition (psychotic major depression 40%; psychotic bipolar depression 30%; depressed schizoaffective disorder 8%; bipolar and schizoaffective mixed states 6 and 7%, respectively). Only 1% of patients with schizophrenia and no patient with delusional disorder or bipolar or schizoaffective manic state showed such delusions. The difference between unipolar and bipolar depression and the other diagnostic groups was highly significant. Delusions of grandiosity characterized mostly patients with manic symptoms (bipolar mania 20%; bipolar mixed states 19%; manic schizoaffective disorder 10%). They were observed significantly more often in bipolar mania than in schizophrenia (7%). Persecutory delusions were broadly distributed across diagnostic categories. However, they were significantly more frequent among patients with schizophrenia and delusional disorder compared with depressed and manic patients. Somatic delusions were also observed in all diagnostic groups, with no group standing out as distinct from the others in terms of an increased prevalence of somatic delusions. Our findings suggest a middle position in the debate between the neurocognitive and the psychopathological approaches. On the one hand, the widespread observation of persecutory delusions suggests the usefulness of searching for non-specific pathogenic mechanisms. On the other hand, the association between some delusional contents and psychiatric diagnosis suggests that a phenomenological analysis of the delusional experience may be a helpful tool for the clinician in the diagnostic process. PMID:29674982

  3. Verbal Memory Impairment in Patients with Subsyndromal Bipolar Disorder.

    PubMed

    Sumiyoshi, Tomiki; Toyomaki, Atsuhito; Kawano, Naoko; Kitajima, Tomoko; Kusumi, Ichiro; Ozaki, Norio; Iwata, Nakao; Sueyoshi, Kazuki; Nakagome, Kazuyuki

    2017-01-01

    Several domains of cognitive function, including learning memory and executive function, are impaired in mood disorders. Also, the relationship between disturbances of these two cognitive domains has been suggested. In line with the recent initiative to establish a standard measure of cognitive decline in bipolar disorder, the present study was conducted to (1) test the criterion-related validity and test-retest reliability of the California Verbal Learning Test (CVLT)-II Japanese version, and (2) determine if type of word learning tasks (i.e., with or without a category structure) affects severity of verbal memory deficits in patients with subsyndromal bipolar disorder. Thirty-six patients with bipolar disorder with mild symptoms and 42 healthy volunteers participated in the study. We first compared effect sizes for memory deficits in patients among the CVLT-II, Brief Assessment of Cognition in Schizophrenia (BACS), and Hopkins Verbal Memory Tests-Revised (HVLT-R). We next evaluated the correlations between scores of the CVLT-II vs. those of the BACS and HVLT-R. Bipolar patients were re-assessed with the same (standard) or alternate forms of the CVLT-II and HVLT-R 1 month later. Scores on the CVLT-II 1-5 Free Recall and Long-delay Free Recall, as well as the HVLT-R Immediate Recall, but not the BACS List Learning were significantly lower for patients compared to control subjects. The effect sizes for cognitive decline due to the illness were comparable when measured by the CVLT-II and HVLT-R, ranging from 0.5 to 0.6. CVLT-II scores were significantly correlated with those of the HVLT-R and BACS. Test-retest reliability of the CVLT-II was acceptable, and no significant practice effect was observed when the alternate form was used. There was no consistent relationship between mood symptoms and performance on the CVLT-II. These results suggest the CVLT-II Japanese version is able to discriminate between bipolar disorder patients and healthy controls with good sensitivity and validity. Data in this study also indicate that the degree of verbal memory deficits in bipolar disorder may be influenced by memory organizational strategy.

  4. A YinYang bipolar fuzzy cognitive TOPSIS method to bipolar disorder diagnosis.

    PubMed

    Han, Ying; Lu, Zhenyu; Du, Zhenguang; Luo, Qi; Chen, Sheng

    2018-05-01

    Bipolar disorder is often mis-diagnosed as unipolar depression in the clinical diagnosis. The main reason is that, different from other diseases, bipolarity is the norm rather than exception in bipolar disorder diagnosis. YinYang bipolar fuzzy set captures bipolarity and has been successfully used to construct a unified inference mathematical modeling method to bipolar disorder clinical diagnosis. Nevertheless, symptoms and their interrelationships are not considered in the existing method, circumventing its ability to describe complexity of bipolar disorder. Thus, in this paper, a YinYang bipolar fuzzy multi-criteria group decision making method to bipolar disorder clinical diagnosis is developed. Comparing with the existing method, the new one is more comprehensive. The merits of the new method are listed as follows: First of all, multi-criteria group decision making method is introduced into bipolar disorder diagnosis for considering different symptoms and multiple doctors' opinions. Secondly, the discreet diagnosis principle is adopted by the revised TOPSIS method. Last but not the least, YinYang bipolar fuzzy cognitive map is provided for the understanding of interrelations among symptoms. The illustrated case demonstrates the feasibility, validity, and necessity of the theoretical results obtained. Moreover, the comparison analysis demonstrates that the diagnosis result is more accurate, when interrelations about symptoms are considered in the proposed method. In a conclusion, the main contribution of this paper is to provide a comprehensive mathematical approach to improve the accuracy of bipolar disorder clinical diagnosis, in which both bipolarity and complexity are considered. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Enhanced neurocognitive functioning and positive temperament in twins discordant for bipolar disorder.

    PubMed

    Higier, Rachel G; Jimenez, Amy M; Hultman, Christina M; Borg, Jacqueline; Roman, Cristina; Kizling, Isabelle; Larsson, Henrik; Cannon, Tyrone D

    2014-11-01

    Based on evidence linking creativity and bipolar disorder, a model has been proposed whereby factors influencing liability to bipolar disorder confer certain traits with positive effects on reproductive fitness. The authors tested this model by examining key traits known to be associated with evolutionary fitness, namely, temperament and neurocognition, in individuals carrying liability for bipolar disorder. Schizophrenia probands and their co-twins were included as psychiatric controls. Twin pairs discordant for bipolar disorder and schizophrenia and control pairs were identified through the Swedish Twin Registry. The authors administered a neuropsychological test battery and temperament questionnaires to samples of bipolar probands, bipolar co-twins, schizophrenia probands, schizophrenia co-twins, and controls. Multivariate mixed-model analyses of variance were conducted to compare groups on temperament and neurocognitive scores. Bipolar co-twins showed elevated scores on a "positivity" temperament scale compared with controls and bipolar probands, while bipolar probands scored higher on a "negativity" scale compared with their co-twins and controls, who did not differ. Additionally, bipolar co-twins showed superior performance compared with controls on tests of verbal learning and fluency, while bipolar probands showed performance decrements across all neurocognitive domains. In contrast, schizophrenia co-twins showed attenuated impairments in positivity and overall neurocognitive functioning relative to their ill proband counterparts. These findings suggest that supra-normal levels of sociability and verbal functioning may be associated with liability for bipolar disorder. These effects were specific to liability for bipolar disorder and did not apply to schizophrenia. Such benefits may provide a partial explanation for the persistence of bipolar illness in the population.

  6. Optimization of a Simple Ship Structural Model Using MAESTRO

    DTIC Science & Technology

    1999-03-01

    Substructures MAESTRO Model Modules . . . MAESTRO Model Girders . . . . MAESTRO Model Tranverse Frames 9 10 11 12 13 Structural and Non-Structural...Weight Distribution 14 Longitudinal Load Distribution on the Model . 15 Tranverse Load Distribution on the Model . . . 16 Hogging Displacement of...Compression, Flange PYCP Panel Yield - Compression, Plate PSPBT Panel Serviceability- Plate Bending Tranverse PSPBL Panel Serviceability - Plate

  7. Brief Report: A Family Risk Study Exploring Bipolar Spectrum Problems and Cognitive Biases in Adolescent Children of Bipolar Parents

    ERIC Educational Resources Information Center

    Espie, Jonathan; Jones, Steven H.; Vance, Yvonne H.; Tai, Sara J.

    2012-01-01

    Children of parents with bipolar disorder are at increased risk of bipolar spectrum diagnoses. This cross-sectional study explores cognitive factors in the prediction of vulnerability to bipolar disorder. Adolescents at high-risk (with a parent with bipolar disorder; n = 23) and age and gender matched adolescents (n = 24) were recruited. Parent…

  8. Quick-Connect, Self-Alining Latch

    NASA Technical Reports Server (NTRS)

    Burns, G. C.; Williams, E. J.

    1983-01-01

    Sturdy latch tolerates 10 degrees of angular mismatch in joining structural elements. Hexagonal passive plate nests in active plate, guided by capture plates and alinement keys and grooves. Center hole in both active and passive plates is 1 meter in diameter. Latch has possible uses a pipe joint, connector for parts of portable structures, and fitting for marine risers on offshore drilling rigs.

  9. Major Depressive Disorder with Sub-threshold Bipolarity in the National Comorbidity Survey Replication

    PubMed Central

    Angst, Jules; Cui, Lihong; Swendsen, J. Joel; Rothen, S.; Cravchik, Anibal; Kessler, Ronald; Merikangas, Kathleen

    2011-01-01

    Objectives There is growing clinical and epidemiologic evidence indicating that major mood disorders form a spectrum from Major Depressive Disorder (MDD) to pure mania. The present investigation examined the prevalence and clinical correlates of MDD with sub-threshold bipolarity vs. pure MDD in the National Comorbidity Survey Replication (NCS-R). Methods The NCS-R is a nationally representative face-to-face household survey of the U.S. population conducted between February, 2001 and April, 2003. Lifetime history of mood disorders, symptoms and clinical indicators of severity were collected using version 3.0 of the WHO Composite International Diagnostic Interview, a fully structured lay-administered diagnostic interview. Results Nearly 40% of study participants with a history of major depressive disorder had a history of sub-threshold hypomania. This subgroup had a younger age of disorder onset, more episodes of depression, and higher rates of comorbidity than those without a history of hypomania, and lower levels of clinical severity than those with bipolar II disorder. Conclusions The findings demonstrate heterogeneity of major depressive disorder and support the validity of inclusion of sub-threshold mania in the diagnostic classification. The broadening of criteria for bipolar disorder would have important implications for research and clinical practice. PMID:20713498

  10. Bipolar Pathophysiology and Development of Improved Treatments

    PubMed Central

    Bowden, Charles L.

    2013-01-01

    The purpose of this review is to provide strategies and their rationale which can facilitate scientifically productive investigations into genetic, neuronal, brain functional and clinical aspects of bipolar disorder. The presentation addresses both factors that have impeded and those that have facilitated landmark advances on the pathophysiology and treatment of bipolar disorders. Application of the strategies can provide a scientific platform that may be useful to basic and clinical scientists for the purposes of achieving seminal advances in understanding pathophysiology, including inherited and experience based contributors to disease expression. Current diagnostic criteria omit certain key symptoms, do not include illness course or family history and lack specification of the importance of fundamental symptomatology. Consideration of such factors in inclusion and exclusion criteria, and in assessment instruments in basic and clinical studies, serves to strengthen the capability of a research plan to test key hypotheses regarding moderating and mediating factors of this complex illness. For example, most studies of brain structure and function and of new interventions have selected subjects on the basis of traditional full syndromal criteria. Evidence indicates that additional consideration of principal behavioral domains of bipolar symptomatology, e.g., anxiety, psychosis, impulsivity, elevated psychomotor and cognitive processing speed, rather than strictly depressive or manic syndromes can provide more homogeneous samples for study, and increase the focus of experimental hypotheses. PMID:18582440

  11. Wave-plate structures, power selective optical filter devices, and optical systems using same

    DOEpatents

    Koplow, Jeffrey P [San Ramon, CA

    2012-07-03

    In an embodiment, an optical filter device includes an input polarizer for selectively transmitting an input signal. The device includes a wave-plate structure positioned to receive the input signal, which includes first and second substantially zero-order, zero-wave plates arranged in series with and oriented at an angle relative to each other. The first and second zero-wave plates are configured to alter a polarization state of the input signal passing in a manner that depends on the power of the input signal. Each zero-wave plate includes an entry and exit wave plate each having a fast axis, with the fast axes oriented substantially perpendicular to each other. Each entry wave plate is oriented relative to a transmission axis of the input polarizer at a respective angle. An output polarizer is positioned to receive a signal output from the wave-plate structure and selectively transmits the signal based on the polarization state.

  12. Elastic stability of biaxially loaded longitudinally stiffened composite structures.

    NASA Technical Reports Server (NTRS)

    Viswanathan, A. V.; Tamekuni, M.; Tripp, L. L.

    1973-01-01

    A linear analysis method is presented for the elastic stability of structures of uniform cross section, that may be idealized as an assemblage of laminated plate-strips, flat and curved, and beams. Each plate-strip and beam covers the entire length of the structure and is simply supported on the edges normal to the longitudinal axis. Arbitrary boundary conditions may be specified on any external longitudinal side of plate-strips. The structure or selected plate-strips may be loaded in any desired combination of inplane biaxial loads. The analysis simultaneously considers all modes of instability and is applicable for the buckling of laminated composite structures. Some numerical results are presented to indicate possible applications.

  13. An explicit plate kinematic model for the orogeny in the southern Uralides

    NASA Astrophysics Data System (ADS)

    Görz, Ines; Hielscher, Peggy

    2010-10-01

    The Palaeozoic Uralides formed in a three plate constellation between Europe, Siberia and Kazakhstan-Tarim. Starting from the first plate tectonic concepts, it was controversially discussed, whether the Uralide orogeny was the result of a relative plate motion between Europe and Siberia or between Europe and Kazakhstan. In this study, we use a new approach to address this problem. We perform a structural analysis on the sphere, reconstruct the positions of the Euler poles of the relative plate rotation Siberia-Europe and Tarim-Europe and describe Uralide structures by their relation to small circles about the two Euler poles. Using this method, changes in the strike of tectonic elements that are caused by the spherical geometry of the Earth's surface are eliminated and structures that are compatible with one of the relative plate motions can be identified. We show that only two Euler poles controlled the Palaeozoic tectonic evolution in the whole West Siberian region, but that they acted diachronously in different regions. We provide an explicit model describing the tectonism in West Siberia by an Euler pole, a sense of rotation and an approximate rotation angle. In the southern Uralides, Devonian structures resulted from a plate rotation of Siberia with respect to Europe, while the Permian structures were caused by a relative plate motion of Kazakhstan-Tarim with respect to Europe. The tectonic pause in the Carboniferous period correlates with a reorganization of the plate kinematics.

  14. Clinical variables and implications of the personality on the outcome of bipolar illness: a pilot study

    PubMed Central

    Casas-Barquero, Nieves; García-López, Olga; Fernández-Argüelles, Pedro; Camacho-Laraña, Manuel

    2007-01-01

    Outcome in bipolar patients is affected by comorbidity. Comorbid personality disorders are frequent and may complicate the course of bipolar illness. This pilot study examined a series of 40 euthymic bipolar patients (DSM-IV criteria) (bipolar I disorder 31, bipolar II disorder 9) to assess the effect of clinical variables and the influence of comorbid personality on the clinical course of bipolar illness. Bipolar patients with a diagnosis of comorbid personality disorder (n = 30) were compared with “pure” bipolar patients (n = 10) with regard to demographic, clinical, and course of illness variables. Comorbid personality disorder was diagnosed in 75% of patients according to ICD-10 criteria, with obsessive-compulsive personality disorder being the most frequent type. Sixty-three per cent of subjects had more than one comorbid personality disorder. Bipolar patients with and without comorbid personality disorder showed no significant differences regarding features of the bipolar illness, although the group with comorbid personality disorder showed a younger age at onset, more depressive episodes, and longer duration of bipolar illness. In subjects with comorbid personality disorders, the number of hospitalizations correlated significantly with depressive episodes and there was an inverse correlation between age at the first episode and duration of bipolar illness. These findings, however, should be interpreted taking into account the preliminary nature of a pilot study and the contamination of the sample with too many bipolar II patients. PMID:19300559

  15. Peri-Elastodynamic Simulations of Guided Ultrasonic Waves in Plate-Like Structure with Surface Mounted PZT.

    PubMed

    Patra, Subir; Ahmed, Hossain; Banerjee, Sourav

    2018-01-18

    Peridynamic based elastodynamic computation tool named Peri-elastodynamics is proposed herein to simulate the three-dimensional (3D) Lamb wave modes in materials for the first time. Peri-elastodynamics is a nonlocal meshless approach which is a scale-independent generalized technique to visualize the acoustic and ultrasonic waves in plate-like structure, micro-electro-mechanical systems (MEMS) and nanodevices for their respective characterization. In this article, the characteristics of the fundamental Lamb wave modes are simulated in a sample plate-like structure. Lamb wave modes are generated using a surface mounted piezoelectric (PZT) transducer which is actuated from the top surface. The proposed generalized Peri-elastodynamics method is not only capable of simulating two dimensional (2D) in plane wave under plane strain condition formulated previously but also capable of accurately simulating the out of plane Symmetric and Antisymmetric Lamb wave modes in plate like structures in 3D. For structural health monitoring (SHM) of plate-like structures and nondestructive evaluation (NDE) of MEMS devices, it is necessary to simulate the 3D wave-damage interaction scenarios and visualize the different wave features due to damages. Hence, in addition, to simulating the guided ultrasonic wave modes in pristine material, Lamb waves were also simulated in a damaged plate. The accuracy of the proposed technique is verified by comparing the modes generated in the plate and the mode shapes across the thickness of the plate with theoretical wave analysis.

  16. Metal hydrides as negative electrode materials for Ni- MH batteries

    NASA Astrophysics Data System (ADS)

    Yartys, V.; Noreus, D.; Latroche, M.

    2016-01-01

    Structural, thermodynamical and electrochemical properties of metallic hydrides belonging to the pseudo-binary family A-Mg-Ni ( A: rare earths) are reviewed and compared. Technology aspects of bipolar cells are also discussed.

  17. Frequency dependence of excitation-contraction of multicellular smooth muscle preparations: the relevance to bipolar electrosurgery.

    PubMed

    Vladimirova, Irina A; Lankin, Yuri N; Philyppov, Igor B; Sushiy, Lyudmyla F; Shuba, Yaroslav M

    2014-01-01

    Bipolar electrosurgical tissue welding uses forceps-like electrodes for grasping the tissues and delivering high-frequency electric current (HFEC) to produce local heat, desiccation, and protein denaturation, resulting in the fusion of the contacting tissues. Although in this technique no electric current is flowing through the whole body to cause electric injury, depending on the frequency of applied energy, it may produce local excitation of intramural nerves, which can propagate beyond the surgical site potentially causing harmful effects. The effects of varying frequency of HFEC on tissue excitability in bipolar electrosurgical modality were studied in vitro using electric field stimulation (EFS) method on multicellular smooth muscle strips of rat vas deferens. Contractile response to 5-s-long sine wave EFS train was taken as the measure of excitation of intramural nerves. EFS-induced contraction consisted of phasic and tonic components. The amplitude of both components decreased with increasing frequency, with tonic component disappearing at about 10 kHz and phasic component at about 50 kHz. Because components of EFS-induced contraction depend on different neurotransmitters, this indicates that various neurotransmitter systems are characterized by distinct frequency dependence, but above 50 kHz they all become inactivated. Bipolar electrosurgical sealing of porcine gut showed no difference in the structure of seal area at HFEC of 67 and 533 kHz. EFS frequency of 50 kHz represents the upper limit for excitation. HFEC above 50 kHz is safe to use for bipolar electrosurgical tissue welding without concerns of excitation propagating beyond the surgical site. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Metacognitions and emotional schemas: a new cognitive perspective for the distinction between unipolar and bipolar depression.

    PubMed

    Batmaz, Sedat; Ulusoy Kaymak, Semra; Kocbiyik, Sibel; Turkcapar, Mehmet Hakan

    2014-10-01

    Clinicians need to make the differential diagnosis of unipolar and bipolar depression to guide their treatment choices. Looking at the differences observed in the metacognitions, and the emotional schemas, might help with this differentiation, and might provide information about the distinct psychotherapeutical targets. Three groups of subjects (166 unipolar depressed, 140 bipolar depressed, and 151 healthy controls) were asked to fill out the Metacognitions Questionnaire-30 (MCQ-30), and the Leahy Emotional Schema Scale (LESS). The clinicians diagnosed the volunteers according to the criteria of DSM-IV-TR with a structured clinical interview (MINI), and rated the moods of the subjects with the Montgomery Asberg Depression Rating Scale (MADRS), and the Young Mania Rating Scale (YMRS). Statistical analyses were undertaken to identify the group differences on the MCQ-30, and the LESS. The bipolar and unipolar depressed patients' scores on the MCQ-30 were significantly different from the healthy controls, but not from each other. On the LESS dimensions of guilt, duration, blame, validation, and acceptance of feelings, all three groups significantly differed from each other. There were no statistically different results on the LESS dimensions of comprehensibility, consensus, and expression. The mood disordered groups scored significantly different than the healthy controls on the LESS dimensions of simplistic view of emotions, numbness, rationality, rumination, higher values, and control. These results suggest that the metacognitive model of unipolar depression might be extrapolated for patients with bipolar depression. These results are also compatible to a great extent with the emotional schema theory of depression. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Influence of religion and supernatural beliefs on clinical manifestation and treatment practices in patients with bipolar disorder.

    PubMed

    Grover, Sandeep; Hazari, Nandita; Aneja, Jitender; Chakrabarti, Subho; Avasthi, Ajit

    2016-08-01

    Religious and supernatural beliefs influence help seeking and treatment practices in bipolar disorder, but these are rarely explored by clinicians. This study aimed to understand religiousness, magico-religious beliefs, prevalence of religious and supernatural psychopathology and treatment practices among patients with bipolar disorder in euthymic state. A total of 185 patients of bipolar disorder currently in remission were assessed cross-sectionally for their clinical profile, current clinical status on the Hamilton Depression Rating Sscale (HDRS), Young Mania Rating Scale (YMRS) and the Global Assessment of Functioning (GAF). A semi structured instrument for magico-religious beliefs, aetiological models, treatment seeking and treatment practices was administered. More than a third of patients (37.8%) had psychopathology with either religious or supernatural content or both in their lifetime. Almost half (45.4%) the patients believed in a supernatural/religious aetiology for their illness. Among the specific causes, planetary influences (13.5%) and God's will (30.8%) were the most common supernatural and religious cause, respectively. Almost half (44.3%) of patients had first treatment contact with religious/supernatural treatment providers. More than 90% of patients reported belief in God, yet about 70% reported that their doctors did not ask them sufficient questions to understand their religiosity. Magico-religious beliefs are common in bipolar disorder and a large number of patients attribute these as aetiological factors for their illness. Consequently they tend to seek treatment from traditional practitioners prior to approaching medical practitioners and may continue treatment with them alongside medical management.

  20. Pituitary gland volumes in bipolar disorder.

    PubMed

    Clark, Ian A; Mackay, Clare E; Goodwin, Guy M

    2014-12-01

    Bipolar disorder has been associated with increased Hypothalamic-Pituitary-Adrenal axis function. The mechanism is not well understood, but there may be associated increases in pituitary gland volume (PGV) and these small increases may be functionally significant. However, research investigating PGV in bipolar disorder reports mixed results. The aim of the current study was twofold. First, to assess PGV in two novel samples of patients with bipolar disorder and matched healthy controls. Second, to perform a meta-analysis comparing PGV across a larger sample of patients and matched controls. Sample 1 consisted of 23 established patients and 32 matched controls. Sample 2 consisted of 39 medication-naïve patients and 42 matched controls. PGV was measured on structural MRI scans. Seven further studies were identified comparing PGV between patients and matched controls (total n; 244 patients, 308 controls). Both novel samples showed a small (approximately 20mm(3) or 4%), but non-significant, increase in PGV in patients. Combining the two novel samples showed a significant association of age and PGV. Meta-analysis showed a trend towards a larger pituitary gland in patients (effect size: .23, CI: -.14, .59). While results suggest a possible small difference in pituitary gland volume between patients and matched controls, larger mega-analyses with sample sizes greater even than those used in the current meta-analysis are still required. There is a small but potentially functionally significant increase in PGV in patients with bipolar disorder compared to controls. Results demonstrate the difficulty of finding potentially important but small effects in functional brain disorders. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Increased impulsivity associated with severity of suicide attempt history in patients with bipolar disorder.

    PubMed

    Swann, Alan C; Dougherty, Donald M; Pazzaglia, Peggy J; Pham, Mary; Steinberg, Joel L; Moeller, F Gerard

    2005-09-01

    Impulsivity is a prominent and measurable characteristic of bipolar disorder that can contribute to risk for suicidal behavior. The purpose of this study was to investigate the relationship between impulsivity and severity of past suicidal behavior, a potential predictor of eventual suicide, in patients with bipolar disorder. In bipolar disorder subjects with either a definite history of attempted suicide or no such history, impulsivity was assessed with both a questionnaire (Barratt Impulsiveness Scale) and behavioral laboratory performance measures (immediate memory/delayed memory tasks). Diagnosis was determined with the Structured Clinical Interview for DSM-IV. Interviews of patients and review of records were used to determine the number of past suicide attempts and the medical severity of the most severe attempt. Subjects with a history of suicide attempts had more impulsive errors on the immediate memory task and had shorter response latencies, especially for impulsive responses. Impulsivity was highest in subjects with the most medically severe suicide attempts. Effects were not accounted for by presence of depression or mania at the time of testing. Barratt Impulsiveness Scale scores were numerically, but not significantly, higher in subjects with suicide attempts. A history of alcohol abuse was associated with greater probability of a suicide attempt. Multivariate analysis showed that ethanol abuse history and clinical state at the time of testing did not have a significant effect after impulsivity was taken into account. These results suggest that a history of severe suicidal behavior in patients with bipolar disorder is associated with impulsivity, manifested as a tendency toward rapid, unplanned responses.

  2. Correlates and impact of obsessive-compulsive comorbidity in bipolar disorder.

    PubMed

    Magalhães, Pedro V S; Kapczinski, Natalia S; Kapczinski, Flávio

    2010-01-01

    Anxiety morbidity in general is frequent and harmful in bipolar disorder. Little is known, however, whether obsessive-compulsive comorbidity entails particular effects. This report aims to evaluate the prevalence and impact of obsessive-compulsive disorder (OCD) comorbidity in a relatively large clinical sample of bipolar disorder, with other lifetime anxiety comorbidities used as a more rigorous control group. A cross-sectional study in a consecutive clinical sample, with anxiety comorbidity derived from the intake Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, was conducted. Anxiety was assessed with the Hamilton Anxiety Rating Scale. The Young Mania Rating Scale and the Hamilton Depression Rating Scale were used to assess (hypo)manic and depressive symptoms. The domains of the WHOQOL BREF were used to evaluate quality of life. Lifetime prevalence of OCD comorbidity was 12.4%. No cases of OCD were detected during mania. Compared with subjects with no anxiety comorbidity, those with lifetime OCD were more likely to have a history of suicide attempts, rapid cycling, and alcohol dependence. Patients with OCD had a lower score on all domains of the WHOQOL. Compared with those with other lifetime anxiety disorders, those with OCD had more anxiety, which mediated a lower WHOQOL social domain. Bipolar disorder patients with obsessive-compulsive comorbidity have a number of indicators of an overall more severe illness. The presence of more anxiety symptoms and a lower social quality of life may be more specific features of the bipolar-OCD comorbidity. Copyright 2010 Elsevier Inc. All rights reserved.

  3. Effect of nonparallel placement of in-circle bipolar radiofrequency ablation probes on volume of tissue ablated with heat sink.

    PubMed

    Pillai, Krishna; Al-Alem, Ihssan; Akhter, Javed; Chua, Terence C; Shehata, Mena; Morris, David L

    2015-06-01

    Percutaneous bipolar radiofrequency ablation (RFA) is a minimally invasive technique for treating liver tumors. It is not always possible to insert the bipolar probes parallel to each other on either side of tumor, since it restricts maneuverability away from vital structures or ablate certain tumor shape. Therefore, we investigated how nonparallel placement of probes affected ablation. Bipolar RFA in parallel and in divergent positions were submerged in tissue model (800 mL egg white) at 37°C and ablated. Temperature probes, T1 and T2 were placed 8.00 mm below the tip of the probes, T3 in between the probe coil elements and T4 and T5 at water inlet and outlet, respectively. Both models with heat sink (+HS) and without (-HS) were investigated. The mean ablated tissue volume, mass, density and height increased linearly with unit angle increase for -HS model. With +HS, a smaller increase in mean volume and mass, a slightly greater increase in mean density but a reduction in height of tissue was seen. The mean ablation time and duration of maximum temperature with +HS was slightly larger, compared with -HS, while -HS ablated at a slightly higher temperature. The heat sink present was minimal for probes in parallel position compared to nonparallel positions. Divergence from parallel insertion of bipolar RFA probes increased the mean volume, mass, and density of tissue ablated. However, the presence of large heat sinks may limit the application of this technique, when tumors border on larger vessels. © The Author(s) 2014.

  4. Factors associated with onset timing, symptoms, and severity of depression identified in the postpartum period.

    PubMed

    Fisher, Sheehan D; Wisner, Katherine L; Clark, Crystal T; Sit, Dorothy K; Luther, James F; Wisniewski, Stephen

    2016-10-01

    Unipolar and bipolar depression identified in the postpartum period have a heterogeneous etiology. The objectives of this study are to examine the risk factors that distinguish the timing of onset for unipolar and bipolar depression and the associations between depression onset by diagnosis, and general and atypical depressive symptoms. Symptoms of depression were assessed at 4- to 6-weeks postpartum by the Structured Interview Guide for the Hamilton Depression Rating Scale-Atypical Depression Symptoms in an obstetrical sample of 727 women. Data were analyzed using ANOVA, Chi-square, and linear regression. Mothers with postpartum onset of depression were more likely to be older, Caucasian, educated, married/cohabitating, have one or no previous child, and have private insurance in contrast to mothers with pre-pregnancy and prenatal onset of depression. Mothers with bipolar depression were more likely to have a pre-pregnancy onset. Three general and two atypical depressive symptoms distinguished pre-pregnancy, during pregnancy, and postpartum depression onset, and the presence of agitation distinguished between unipolar and bipolar depression. The sample was urban, which may not be generalizable to other populations. The study was cross-sectional, which excludes potential late onset of depression (after 4-6 weeks) in the first postpartum year. A collective set of factors predicted the onset of depression identified in the postpartum for mothers distinguished by episodes of unipolar versus bipolar depression, which can inform clinical interventions. Future research on the onset of major depressive episodes could inform prophylactic and early psychiatric interventions. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Translatory shock absorber for attitude sensors

    NASA Technical Reports Server (NTRS)

    Vonpragenau, G. L.; Morgan, I. T., Jr.; Kirby, C. A. (Inventor)

    1976-01-01

    A translatory shock absorber is provided for mounting an attitude sensor thereon for isolating a sensor from translatory vibrations. The translatory shock absorber includes a hollow block structure formed as one piece to form a parallelogram. The absorber block structure includes a movable top plate for supporting the attitude sensor and a fixed base plate with opposed side plates interposed between. At the junctions of the side plates, and the base and top plates, there are provided grooves which act as flexible hinges for attenuating translatory vibrations. A damping material is supported on a pedestal which is carried on the base plate between the side plates thereof. The top of the damping material rests against the bottom surface of the top plate for eliminating the resonant peaks of vibration.

  6. Progressive phase trends in plates with embedded acoustic black holes.

    PubMed

    Conlon, Stephen C; Feurtado, Philip A

    2018-02-01

    Acoustic black holes (ABHs) have been explored and demonstrated to be effective passive treatments for broadband noise and vibration control. Performance metrics for assessing damping concepts are often focused on maximizing structural damping loss factors. Optimally performing damping treatments can reduce the resonant response of a driven system well below the direct field response. This results in a finite structure whose vibration input-output response follows that of an infinite structure. The vibration mobility transfer functions between locations on a structure can be used to assess the structure's vibration response phase, and compare its phase response characteristics to those of idealized systems. This work experimentally explores the phase accumulation in finite plates, with and without embedded grids of ABHs. The measured results are compared and contrasted with theoretical results for finite and infinite uniform plates. Accumulated phase characteristics, their spatial dependence and limits, are examined for the plates and compared to theoretical estimates. The phase accumulation results show that the embedded acoustic black hole treatments can significantly enhance the damping of the plates to the point that their phase accumulation follows that of an infinite plate.

  7. A gallium phosphide high-temperature bipolar junction transistor

    NASA Technical Reports Server (NTRS)

    Zipperian, T. E.; Dawson, L. R.; Chaffin, R. J.

    1981-01-01

    Preliminary results are reported on the development of a high temperature (350 C) gallium phosphide bipolar junction transistor (BJT) for geothermal and other energy applications. This four-layer p(+)n(-)pp(+) structure was formed by liquid phase epitaxy using a supercooling technique to insure uniform nucleation of the thin layers. Magnesium was used as the p-type dopant to avoid excessive out-diffusion into the lightly doped base. By appropriate choice of electrodes, the device may also be driven as an n-channel junction field-effect transistor. The initial design suffers from a series resistance problem which limits the transistor's usefulness at high temperatures.

  8. Ion density evolution in a high-power sputtering discharge with bipolar pulsing

    NASA Astrophysics Data System (ADS)

    Britun, N.; Michiels, M.; Godfroid, T.; Snyders, R.

    2018-06-01

    Time evolution of sputtered metal ions in high power impulse magnetron sputtering (HiPIMS) discharge with a positive voltage pulse applied after a negative one (regime called "bipolar pulse HiPIMS"—BPH) is studied using 2-D density mapping. It is demonstrated that the ion propagation dynamics is mainly affected by the amplitude and duration of the positive pulse. Such effects as ion repulsion from the cathode and the ionization zone shrinkage due to electron drift towards the cathode are clearly observed during the positive pulse. The BPH mode also alters the film crystallographic structure, as observed from X-ray diffraction analysis.

  9. Effect of Electronegativity on Bipolar Resistive Switching in a WO3-Based Asymmetric Capacitor Structure.

    PubMed

    Kim, Jongmin; Inamdar, Akbar I; Jo, Yongcheol; Woo, Hyeonseok; Cho, Sangeun; Pawar, Sambhaji M; Kim, Hyungsang; Im, Hyunsik

    2016-04-13

    This study investigates the transport and switching time of nonvolatile tungsten oxide based resistive-switching (RS) memory devices. These devices consist of a highly resistive tungsten oxide film sandwiched between metal electrodes, and their RS characteristics are bipolar in the counterclockwise direction. The switching voltage, retention, endurance, and switching time are strongly dependent on the type of electrodes used, and we also find quantitative and qualitative evidence that the electronegativity (χ) of the electrodes plays a key role in determining the RS properties and switching time. We also propose an RS model based on the role of the electronegativity at the interface.

  10. Total Dose Effects in Conventional Bipolar Transistors

    NASA Technical Reports Server (NTRS)

    Johnston, A. H.; Swift, G. W.; Rax, B. G.

    1994-01-01

    This paper examines various factors in bipolar device construction and design, and discusses their impact on radiation hardness. The intent of the paper is to improve understanding of the underlying mechanisms for practical devices without special test structures, and to provide (1) guidance in ways to select transistor designs that are more resistant to radiation damage, and (2) methods to estimate the maximum amount of damage that might be expected from a basic transistor design. The latter factor is extremely important in assessing the risk that future lots of devices will be substantially below design limits, which are usually based on test data for older devices.

  11. Quantum-well-base heterojunction bipolar light-emitting transistor

    NASA Astrophysics Data System (ADS)

    Feng, M.; Holonyak, N.; Chan, R.

    2004-03-01

    This letter reports the enhanced radiative recombination realized by incorporating InGaAs quantum wells in the base layer of light-emitting InGaP/GaAs heterojunction bipolar transistors (LETs) operating in the common-emitter configuration. Two 50 Å In1-xGaxAs (x=85%) quantum wells (QWs) acting, in effect, as electron capture centers ("traps") are imbedded in the 300 Å GaAs base layer, thus improving (as a "collector" and recombination center) the light emission intensity compared to a similar LET structure without QWs in the base. Gigahertz operation of the QW LET with simultaneously amplified electrical output and an optical output with signal modulation is demonstrated.

  12. Thwarted interpersonal needs and suicide ideation: Comparing psychiatric inpatients with bipolar and non-bipolar mood disorders.

    PubMed

    Taylor, Nathanael J; Mitchell, Sean M; Roush, Jared F; Brown, Sarah L; Jahn, Danielle R; Cukrowicz, Kelly C

    2016-12-30

    Psychiatric inpatients are at heightened risk for suicide, and evidence suggests that psychiatric inpatients with bipolar mood disorders may be at greater risk for suicide ideation compared to those with non-bipolar mood disorders. There is a paucity of research directly comparing risk factors for suicide ideation in bipolar versus non-bipolar mood disorders in an inpatient sample. The current study sought to clarify the association between two constructs from the interpersonal theory of suicide (i.e., perceived burdensomeness and thwarted belongingness) in leading to suicide ideation among psychiatric inpatients with bipolar and non-bipolar mood disorders. Participants were (N=90) psychiatric inpatients with a bipolar (n = 20) or non-bipolar mood disorder (n=70; per their medical charts). Perceived burdensomeness, but not thwarted belongingness, was significantly associated with suicide ideation after adjusting for other covariates. This suggests perceived burdensomeness may play a key role in suicide ideation among psychiatric inpatients with any mood disorder and highlights the importance of assessment and intervention of perceived burdensomeness in this population. Contrary to our hypothesis, mood disorder group (i.e., bipolar versus non-bipolar) did not moderate the relations between perceived burdensomeness/thwarted belongingness and suicide ideation. Published by Elsevier Ireland Ltd.

  13. Hypnotic susceptibility and affective states in bipolar I and II disorders.

    PubMed

    Zhang, Bingren; Wang, Jiawei; Zhu, Qisha; Ma, Guorong; Shen, Chanchan; Fan, Hongying; Wang, Wei

    2017-11-09

    Highly hypnotizable individuals have impaired executive function, elevated motor impulsivity and increased emotional sensitivity, which are sometimes found in bipolar disorder patients. It is then reasonable to assume that certain aspects of hypnotic susceptibility differ with the types of bipolar disorder. The Stanford Hypnotic Susceptibility Scale: Form C (SHSS:C) test, the Mood Disorder Questionnaire (MDQ), the Hypomanic Checklist-32 (HCL-32) and the Plutchick-van Praag Depression Inventory (PVP) were applied to 62 patients with bipolar I disorder, 33 bipolar II disorder, and 120 healthy volunteers. The passing rate of the SHSS:C 'Moving hands apart' item was higher in bipolar I patients than in controls, whereas for 'Mosquito hallucination' the rate was lower. Bipolar I and II patients scored significantly higher on MDQ, HCL-32 and PVP scales than controls. The passing rates of 'Mosquito hallucination' in controls, 'Arm rigidity' in bipolar I, and 'Age regression' in bipolar II predicted the respective MDQ scores. In contrast to cognitive suggestions, bipolar I patients followed motor suggestions more often under hypnosis. Furthermore, both bipolar disorder patients and healthy volunteers demonstrated associations between mania levels and certain hypnotic susceptibility features. Our study aids in better understanding the altered conscious states in bipolar disorders, and encourages the use of related psychotherapy for these patients.

  14. Understanding the Links among the Magnetic Fields, Filament, Bipolar Bubble, and Star Formation in RCW 57A Using NIR Polarimetry

    NASA Astrophysics Data System (ADS)

    Eswaraiah, Chakali; Lai, Shih-Ping; Chen, Wen-Ping; Pandey, A. K.; Tamura, M.; Maheswar, G.; Sharma, S.; Wang, Jia-Wei; Nishiyama, S.; Nakajima, Y.; Kwon, Jungmi; Purcell, R.; Magalhães, A. M.

    2017-12-01

    The influence of magnetic fields (B-fields) on the formation and evolution of bipolar bubbles, due to the expanding ionization fronts (I-fronts) driven by the H II regions that are formed and embedded in filamentary molecular clouds, has not been well-studied yet. In addition to the anisotropic expansion of I-fronts into a filament, B-fields are expected to introduce an additional anisotropic pressure, which might favor the expansion and propagation of I-fronts forming a bipolar bubble. We present results based on near-infrared polarimetric observations toward the central ˜8‧ × 8‧ area of the star-forming region RCW 57A, which hosts an H II region, a filament, and a bipolar bubble. Polarization measurements of 178 reddened background stars, out of the 919 detected sources in the JHK s bands, reveal B-fields that thread perpendicularly to the filament long axis. The B-fields exhibit an hourglass morphology that closely follows the structure of the bipolar bubble. The mean B-field strength, estimated using the Chandrasekhar-Fermi method (CF method), is 91 ± 8 μG. B-field pressure dominates over turbulent and thermal pressures. Thermal pressure might act in the same orientation as the B-fields to accelerate the expansion of those I-fronts. The observed morphological correspondence among the B-fields, filament, and bipolar bubble demonstrate that the B-fields are important to the cloud contraction that formed the filament, to the gravitational collapse and star formation in it, and in feedback processes. The last one includes the formation and evolution of mid-infrared bubbles by means of B-field supported propagation and expansion of I-fronts. These may shed light on preexisting conditions favoring the formation of the massive stellar cluster in RCW 57A.

  15. Cognitive remediation versus active computer control in bipolar disorder with psychosis: study protocol for a randomized controlled trial.

    PubMed

    Lewandowski, Kathryn Eve; Sperry, Sarah H; Ongur, Dost; Cohen, Bruce M; Norris, Lesley A; Keshavan, Matcheri S

    2016-03-12

    Cognitive dysfunction is a major feature of bipolar disorder with psychosis and is strongly associated with functional outcomes. Computer-based cognitive remediation has shown promise in improving cognition in patients with schizophrenia. However, despite similar neurocognitive deficits between patients with schizophrenia and bipolar disorder, few studies have extended neuroscience-based cognitive remediation programs to this population. The Treatment to Enhance Cognition in Bipolar Disorder study is an investigator-initiated, parallel group, randomized, blinded clinical trial of an Internet-based cognitive remediation protocol for patients with bipolar disorder I with psychosis (n = 100). We also describe the development of our dose-matched active control paradigm. Both conditions involve 70 sessions of computer-based activities over 24 weeks. The control intervention was developed to mirror the treatment condition in dose and format but without the neuroplasticity-based task design and structure. All participants undergo neuropsychological and clinical assessment at baseline, after approximately 25 hours of study activities, post treatment, and after 6 months of no study contact to assess durability. Neuroimaging at baseline and post treatment are offered in an "opt-in" format. The primary outcomes are scores on the MATRICS battery; secondary and exploratory outcomes include measures of clinical symptoms, community functioning, and neuroimaging changes. Associations between change in cognitive measures and change in community functioning will be assessed. Baseline predictors of treatment response will be examined. The present study is the first we are aware of to implement an Internet-based cognitive remediation program in patients with bipolar disorder with psychosis and to develop a comparable web-based control paradigm. The mixed online and study-site format allows accessible treatment while providing weekly staff contact and bridging. Based on user-provided feedback, participant blinding is feasible. ClinicalTrials.gov NCT01470781 ; 11 July 2011.

  16. Risk of sexual transmitted infection following bipolar disorder: a nationwide population-based cohort study.

    PubMed

    Lee, Shyh-Chyang; Hu, Chang-Kuo; Hung, Jeng-Hsiu; Yang, Albert C; Tsai, Shih-Jen; Huang, Min-Wei; Hu, Li-Yu; Shen, Cheng-Che

    2018-04-03

    Bipolar disorder is a severe mental disorder associated with functional and cognitive impairment. Numerous studies have investigated associations between sexually transmitted infections (STIs) and psychiatric illnesses. However, the results of these studies are controversial. We explored the association between bipolar disorder and the subsequent development of STIs, including human immunodeficiency virus infection; primary, secondary, and latent syphilis; genital warts; gonorrhea; chlamydial infection; and trichomoniasis. The bipolar cohort consisted of 1293 patients, and the comparison cohort consisted of 5172 matched control subjects without bipolar disorder. The incidence of subsequent STIs (hazard ratio (HR) = 2.23, 95% confidence interval (CI) 1.68-2.96) was higher among the patients with bipolar disorder than in the comparison cohort. Furthermore, female gender is a risk factor for acquisition of STIs (HR = 2.36, 95% CI 1.73-4.89) among patients with bipolar disorder. For individual STIs, the results indicated that the patients with bipolar disorder exhibited a markedly higher risk for subsequently contracting syphilis, genital warts, and trichomoniasis. Bipolar disorder might increase the risk of subsequent newly diagnosed STIs, including syphilis, genital warts, and trichomoniasis. Clinicians should pay particular attention to STIs in patients with bipolar disorder. Patients with bipolar disorder, especially those with a history of high-risk sexual behaviors, should be routinely screened for STIs. We identified patients who were diagnosed with bipolar disorder in the Taiwan National Health Insurance Research Database. A comparison cohort was constructed of patients without bipolar disorder who were matched with the bipolar cohort according to age and gender. The occurrence of subsequent new-onset STIs was evaluated in both cohorts.

  17. Patients With Co-Occurring Bipolar Disorder and Posttraumatic Stress Disorder: A Rapid Review of the Literature.

    PubMed

    Cerimele, Joseph M; Bauer, Amy M; Fortney, John C; Bauer, Mark S

    2017-05-01

    To summarize the current literature on epidemiology, clinical correlates, and treatment of individuals with co-occurring bipolar disorder and posttraumatic stress disorder (PTSD). We conducted a focused, time-sensitive review called "rapid review" in November 2015, using keyword searches (including keywords bipolar disorder, post-traumatic stress disorder, PTSD, and others) in PubMed for studies of adults with co-occurring bipolar disorder and PTSD. Results were sorted and systematically searched. An article was excluded if it did not describe adult patients with co-occurring PTSD and bipolar disorder or did not report original data on epidemiology, clinical correlates, or treatment. Information on study characteristics including population studied and key findings were extracted onto a data collection tool. Thirty-two articles were included. Over two-thirds of articles reported epidemiology of co-occurring bipolar disorder and PTSD. Prevalence of PTSD among individuals with bipolar disorder ranged from 4% to 40%, with women and those with bipolar I versus bipolar II disorder experiencing higher prevalence of PTSD. Prevalence of bipolar disorder among individuals with PTSD ranged from 6% to 55%. Baseline PTSD or bipolar disorder was associated with incidence of the other illness. Individuals with co-occurring bipolar disorder and PTSD experienced high symptom burden and low quality of life. No studies evaluated prospective treatment of patients with co-occurring bipolar disorder and PTSD. Bipolar disorder and PTSD commonly co-occur and result in greater symptom burden than either condition alone. Few published treatment strategies exist for patients with both conditions. © Copyright 2017 Physicians Postgraduate Press, Inc.

  18. Bariatric surgery in patients with bipolar spectrum disorders: Selection factors, post-operative visit attendance, and weight outcomes

    PubMed Central

    Friedman, Kelli E.; Applegate, Katherine; Portenier, Dana; McVay, Megan

    2017-01-01

    Background As many of 3% of bariatric surgery candidates are diagnosed with a bipolar spectrum disorder. Objectives 1) To describe differences between patients with bipolar spectrum disorders who are approved and not approved for surgery by the mental health evaluator. 2) To examine surgical outcomes of patients with bipolar spectrum disorders. Setting Academic medical center, United States. Methods A retrospective record review was conducted of consecutive patients who applied for bariatric surgery between 2004 and 2009. Patients diagnosed with bipolar spectrum disorders who were approved for surgery (n=42) were compared with patients with a bipolar spectrum disorder who were not approved (n=31) and to matched control surgical patients without a bipolar spectrum diagnosis (n=29) on a variety of characteristics and surgical outcomes. Results Of bariatric surgery candidates diagnosed with a bipolar spectrum disorder who applied for surgery, 57% were approved by the psychologist and 48% ultimately had surgery. Patients with a bipolar spectrum disorder who were approved for surgery were less likely to have had a previous psychiatric hospitalizations than those who were not approved for surgery. Bariatric surgery patients diagnosed with a bipolar spectrum disorder were less likely to attend follow-up care appointments 2 or more years post-surgery compared to matched patients without bipolar disorder. Among patients with available data, those with a bipolar spectrum disorder and matched patients had similar weight loss at 12 months (n=21 for bipolar, n=24 for matched controls) and at 2 or more years (mean=51 months; n=11 for bipolar, n=20 for matched controls). Conclusions Patients diagnosed with a bipolar spectrum disorder have a high rate of delay/denial for bariatric surgery based on the psychosocial evaluation and are less likely to attend medical follow-up care 2 or more years post-surgery. Carefully screened patients with bipolar disorder who engage in long-term follow-up care may benefit from bariatric surgery. PMID:28169206

  19. Bipolar Disorder - Multiple Languages

    MedlinePlus

    ... Russian (Русский) Expand Section Bipolar Disorder (An Introduction) - English PDF Bipolar Disorder (An Introduction) - Русский (Russian) PDF Bipolar Disorder (An Introduction) - English MP3 Bipolar Disorder (An Introduction) - Русский (Russian) MP3 ...

  20. Bipolar electrochemistry: from materials science to motion and beyond.

    PubMed

    Loget, Gabriel; Zigah, Dodzi; Bouffier, Laurent; Sojic, Neso; Kuhn, Alexander

    2013-11-19

    Bipolar electrochemistry, a phenomenon which generates an asymmetric reactivity on the surface of conductive objects in a wireless manner, is an important concept for many purposes, from analysis to materials science as well as for the generation of motion. Chemists have known the basic concept for a long time, but it has recently attracted additional attention, especially in the context of micro- and nanoscience. In this Account, we introduce the fundamentals of bipolar electrochemistry and illustrate its recent applications, with a particular focus on the fields of materials science and dynamic systems. Janus particles, named after the Roman god depicted with two faces, are currently in the heart of many original investigations. These objects exhibit different physicochemical properties on two opposite sides. This makes them a unique class of materials, showing interesting features. They have received increasing attention from the materials science community, since they can be used for a large variety of applications, ranging from sensing to photosplitting of water. So far the great majority of methods developed for the generation of Janus particles breaks the symmetry by using interfaces or surfaces. The consequence is often a low time-space yield, which limits their large scale production. In this context, chemists have successfully used bipolar electrodeposition to break the symmetry. This provides a single-step technique for the bulk production of Janus particles with a high control over the deposit structure and morphology, as well as a significantly improved yield. In this context, researchers have used the bipolar electrodeposition of molecular layers, metals, semiconductors, and insulators at one or both reactive poles of bipolar electrodes to generate a wide range of Janus particles with different size, composition and shape. In using bipolar electrochemistry as a driving force for generating motion, its intrinsic asymmetric reactivity is again the crucial aspect, as there is no directed motion without symmetry breaking. Controlling the motion of objects at the micro- and nanoscale is of primary importance for many potential applications, ranging from medical diagnosis to nanosurgery, and has generated huge interest in the scientific community in recent years. Several original approaches to design micro- and nanomotors have been explored, with propulsion strategies based on chemical fuelling or on external fields. The first strategy is using the asymmetric particles generated by bipolar electrodeposition and employing them directly as micromotors. We have demonstrated this by using the catalytic and magnetic properties of Janus objects. The second strategy is utilizing bipolar electrochemistry as a direct trigger of motion of isotropic particles. We developed mechanisms based on a simultaneous dissolution and deposition, or on a localized asymmetric production of bubbles. We then used these for the translation, the rotation and the levitation of conducting objects. These examples give insight into two interesting fields of applications of the concept of bipolar electrochemistry, and open perspectives for future developments in materials science and for generating motion at different scales.

  1. Vibration-response due to thickness loss on steel plate excited by resonance frequency

    NASA Astrophysics Data System (ADS)

    Kudus, S. A.; Suzuki, Y.; Matsumura, M.; Sugiura, K.

    2018-04-01

    The degradation of steel structure due to corrosion is a common problem found especially in the marine structure due to exposure to the harsh marine environment. In order to ensure safety and reliability of marine structure, the damage assessment is an indispensable prerequisite for plan of remedial action on damaged structure. The main goal of this paper is to discuss simple vibration measurement on plated structure to give image on overview condition of the monitored structure. The changes of vibration response when damage was introduced in the plate structure were investigated. The damage on plate was simulated in finite element method as loss of thickness section. The size of damage and depth of loss of thickness were varied for different damage cases. The plate was excited with lower order of resonance frequency in accordance estimate the average remaining thickness based on displacement response obtain in the dynamic analysis. Significant reduction of natural frequency and increasing amplitude of vibration can be observed in the presence of severe damage. The vibration analysis summarized in this study can serve as benchmark and reference for researcher and design engineer.

  2. High resistance ratio of bipolar resistive switching in a multiferroic/high-K Bi(Fe0.95Cr0.05)O3/ZrO2/Pt heterostructure

    NASA Astrophysics Data System (ADS)

    Dong, B. W.; Miao, Jun; Han, J. Z.; Shao, F.; Yuan, J.; Meng, K. K.; Wu, Y.; Xu, X. G.; Jiang, Y.

    2018-03-01

    An novel heterostructure composed of multiferroic Bi(Fe0.95Cr0.05)O3 (BFCO) and high-K ZrO2 (ZO) layers is investigated. Ferroelectric and electrical properties of the BFZO/ZO heterostructure have been investigated. A pronounced bipolar ferroelectric resistive switching characteristic was achieved in the heterostructure at room temperature. Interestingly, the BFCO/ZO structures exhibit a reproducible resistive switching with a high On/Off resistance ratio ∼2×103 and long retention time. The relationship between polarization and band structure at the interface of BFCO/ZO bilayer under the positive and negative sweepings has been discussed. As a result, the BFCO/ZO multiferroic/high-K heterostructure with high On/Off resistance ratio and long retention characterizes, exhibits a potential in future nonvolatile memory application.

  3. Excellent selector performance in engineered Ag/ZrO2:Ag/Pt structure for high-density bipolar RRAM applications

    NASA Astrophysics Data System (ADS)

    Wang, Chao; Song, Bing; Zeng, Zhongming

    2017-12-01

    A high-performance selector with bidirectional threshold switching (TS) characteristics of Ag/ZrO2/Pt structure was prepared by incorporating metallic Ag into the ZrO2 matrix. The bidirectional TS device exhibited excellent switching uniformity, forming-free behavior, ultra-low off current of <1 nA and adjustable selectivity (from 102 to 107). The experiment results confirmed that metallic Ag clusters were penetrated into the ZrO2 matrix during the annealing process, which would function as an effective active source responsible for the bidirectional TS. The volatile behavior could be explained by the self-dissolution of unstable filaments caused by minimization of the interfacial energy and thermal effect. Furthermore, a bipolar-type one selector-one resistor (1S-1R) memory device was successfully fabricated and exhibited significant suppression of the undesired sneak current, indicating the great potential as selector in a cross-point array.

  4. Selective electroless plating of 3D-printed plastic structures for three-dimensional microwave metamaterials

    NASA Astrophysics Data System (ADS)

    Ishikawa, Atsushi; Kato, Taiki; Takeyasu, Nobuyuki; Fujimori, Kazuhiro; Tsuruta, Kenji

    2017-10-01

    A technique of selective electroless plating onto PLA-ABS (Polylactic Acid-Acrylonitrile Butadiene Styrene) composite structures fabricated by three-dimensional (3D) printing is demonstrated to construct 3D microwave metamaterials. The reducing activity of the PLA surface is selectively enhanced by the chemical modification involving Sn2+ in a simple wet process, thereby forming a highly conductive Ag-plated membrane only onto the PLA surface. The fabricated metamaterial composed of Ag-plated PLA and non-plated ABS parts is characterized experimentally and numerically to demonstrate the important bi-anisotropic microwave responses arising from the 3D nature of metallodielectric structures. Our approach based on a simple wet chemical process allows for the creation of highly complex 3D metal-insulator structures, thus paving the way toward the sophisticated microwave applications of the 3D printing technology.

  5. The relationship between borderline personality disorder and bipolar disorder

    PubMed Central

    Zimmerman, Mark; Morgan, Theresa A.

    2013-01-01

    It is clinically important to recognize both bipolar disorder and borderline personality disorder (BPD) in patients seeking treatment for depression, and it is important to distinguish between the two. Research considering whether BPD should be considered part of a bipolar spectrum reaches differing conclusions. We reviewed the most studied question on the relationship between BPD and bipolar disorder: their diagnostic concordance. Across studies, approximately 10% of patients with BPD had bipolar I disorder and another 10% had bipolar II disorder. Likewise, approximately 20% of bipolar II patients were diagnosed with BPD, though only 10% of bipolar I patients were diagnosed with BPD. While the comorbidity rates are substantial, each disorder is nontheless diagnosed in the absence of the other in the vast majority of cases (80% to 90%). In studies examining personality disorders broadly, other personality disorders were more commonly diagnosed in bipolar patients than was BPD. Likewise, the converse is also true: other axis I disorders such as major depression, substance abuse, and post-traumatic stress disorder are also more commonly diagnosed in patients with BPD than is bipolar disorder. These findings challenge the notion that BPD is part of the bipolar spectrum. PMID:24174890

  6. Emotion in Bipolar I Disorder: Implications for Functional and Symptom Outcomes

    PubMed Central

    Johnson, Sheri L.; Tharp, Jordan A.; Peckham, Andrew D.; McMaster, Kaja J.

    2015-01-01

    Despite the centrality of emotion disturbance in neurobiological models of bipolar disorder, the behavioral literature has not yet clearly identified the most central aspects of emotion disturbance in bipolar disorder. Toward this aim, we gathered a battery of emotion-related measures in 67 persons diagnosed with bipolar I disorder as assessed with SCID and a well-matched control group of 58 persons without a history of mood disorders. Those with bipolar disorder were interviewed monthly until they achieved remission, and then tested on emotion measures. A subset of 36 participants with bipolar disorder completed symptom severity interviews at 12-month follow-up. Factor analyses indicated four emotion factor scores: Negative Emotion, Positive Emotion, Reappraisal and Suppression. Bivariate analyses suggested that bipolar disorder was tied to a host of emotion disturbances, but multivariate analyses suggested that bipolar disorder was particularly tied to elevations of Negative Emotion. High Negative Emotion, low Positive Emotion, and high Suppression were conjointly related to lower functioning. Reappraisal predicted declines in depression over time for those with bipolar disorder. Findings highlight the importance of considering the overall profile of emotion disturbance in bipolar disorder. Emotion and emotion regulation appear central to a broad range of outcomes in bipolar disorder. PMID:26480234

  7. Toward the definition of a bipolar prodrome: Dimensional predictors of bipolar spectrum disorder in at-risk youth

    PubMed Central

    Hafeman, Danella M.; Merranko, John; Axelson, David; Goldstein, Benjamin I.; Goldstein, Tina; Monk, Kelly; Hickey, Mary Beth; Sakolsky, Dara; Diler, Rasim; Iyengar, Satish; Brent, David; Kupfer, David; Birmaher, Boris

    2016-01-01

    Objective We aimed to assess dimensional symptomatic predictors of new-onset bipolar spectrum disorder in youth at familial risk of bipolar disorder (“at-risk” youth). Method Offspring aged 6–18 of parents with bipolar-I/II disorder (n=391) and offspring of community controls (n=248) were recruited without regard to non-bipolar psychopathology. At baseline, 8.4% (33/391) of offspring of bipolar parents had bipolar spectrum; 14.7% (44/299) of offspring with follow-up developed new-onset bipolar spectrum (15 with bipolar-I/II) over eight years. Scales collected at baseline and follow-up were reduced using factor analyses; factors (both at baseline and visit proximal to conversion or last contact) were then assessed as predictors of new-onset bipolar spectrum. Results Relative to community control offspring, at-risk and bipolar offspring had higher baseline levels of anxiety/depression, inattention/disinhibition, externalizing, subsydromal manic, and affective lability symptoms (p<.05). The strongest predictors of new-onset bipolar spectrum were: baseline anxiety/depression, baseline and proximal affective lability, and proximal subsyndromal manic symptoms (p<.05). While affective lability and anxiety/depression were elevated throughout follow-up in those who later developed bipolar spectrum, manic symptoms increased up to the point of conversion. A path analysis supported the hypothesized model that affective lability at baseline predicted new-onset bipolar spectrum, in part, through increased manic symptoms at the visit prior to conversion; earlier parental age of mood disorder onset also significantly increased risk of conversion (p<.001). While youth without anxiety/depression, affective lability, and mania (and with a parent with older age of mood disorder onset) had a 2% predicted chance of conversion to bipolar spectrum, those with all risk factors had a 49% predicted chance of conversion. Conclusions Dimensional measures of anxiety/depression, affective lability, and mania are important predictors of new-onset bipolar spectrum in this population of at-risk youth. These symptoms emerged from among numerous other candidates, underscoring the potential clinical and research utility of these findings. PMID:26892940

  8. Technical Note: Interleaved Bipolar Acquisition and Low-rank Reconstruction for Water-Fat Separation in MRI.

    PubMed

    Cho, JaeJin; Park, HyunWook

    2018-05-17

    To acquire interleaved bipolar data and reconstruct the full data using low-rank property for water fat separation. Bipolar acquisition suffers from issues related to gradient switching, the opposite gradient polarities, and other system imperfections, which prevent accurate water-fat separation. In this study, an interleaved bipolar acquisition scheme and a low-rank reconstruction method were proposed to reduce issues from the bipolar gradients while achieving a short imaging time. The proposed interleaved bipolar acquisition scheme collects echo-time signals from both gradient polarities; however, the sequence increases the imaging time. To reduce the imaging time, the signals were subsampled at every dimension of k-space. The low-rank property of the bipolar acquisition was defined and exploited to estimate the full data from the acquired subsampled data. To eliminate the bipolar issues, in the proposed method, the water-fat separation was performed separately for each gradient polarity, and the results for the positive and negative gradient polarities were combined after the water-fat separation. A phantom study and in-vivo experiments were conducted on a 3T Siemens Verio system. The results for the proposed method were compared with the results of the fully sampled interleaved bipolar acquisition and Soliman's method, which was the previous water-fat separation approach for reducing the issues of bipolar gradients and accelerating the interleaved bipolar acquisition. The proposed method provided accurate water and fat images without the issues of bipolar gradients and demonstrated a better performance compared with the results of the previous methods. The water-fat separation using the bipolar acquisition has several benefits including a short echo-spacing time. However, it suffers from bipolar-gradient issues such as strong gradient switching, system imperfection, and eddy current effects. This study demonstrated that accurate water-fat separated images can be obtained using the proposed interleaved bipolar acquisition and low-rank reconstruction by using the benefits of the bipolar acquisition while reducing the bipolar-gradient issues with a short imaging time. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Cognitive Style Index: Further Investigation of the Factor Structure with an American Student Sample

    ERIC Educational Resources Information Center

    Backhaus, Kristin; Liff, Joshua P.

    2007-01-01

    The present study investigates the factor structure of the Cognitive Style Index (CSI), comparing the unitary, bipolar continuum of intuition-analysis, the theory upon which the CSI is predicated, with the two-factor theory of cognitive style. We conducted both confirmatory and exploratory factor analyses on data from a sample of 222 American…

  10. Overactive lifestyle in patients with fibromyalgia as a core feature of bipolar spectrum disorder.

    PubMed

    Alciati, Alessandra; Sarzi-Puttini, Piercarlo; Batticciotto, Alberto; Torta, Riccardo; Gesuele, Felice; Atzeni, Fabiola; Angst, Jules

    2012-01-01

    To test the hypothesis that the premorbid overactivity previously described in subjects with fibromyalgia is a core feature of the manic/hypomanic symptoms characterising bipolar spectrum disorders. 110 consecutive patients with fibromyalgia were assessed for bipolar spectrum disorders using both categorical and dimensional approaches. The first was based on a version of the DSM-IV SCID-CV interview, modified to improve the detection of bipolar spectrum disorders, the second on the hypomania symptom checklist HCL-32, which adopts a dimensional perspective of the manic/hypomanic component of mood by including sub-syndromal hypomania. Both DSM-IV and Zurich criteria diagnosed high rates of bipolar spectrum disorder in patients with fibromyalgia (70% and 86.3%, respectively). Individuals with a major bipolar spectrum disorder (bipolar II disorder) and with a minor bipolar spectrum disorder (subthreshold depression and hypomania) did not differ in their demographic and clinical aspects. Hypomanic symptom counts on the HCL-32 confirmed high estimates of the bipolar spectrum, with 79% of subjects with fibromyalgia scoring 14 (threshold for hypomania) or above. Overactivity reported in previous studies may be considered a core feature of hypomanic symptoms or syndromes comorbid with bipolar spectrum disorders. Major and minor bipolar spectrum disorders are not associated with differences in demographic or clinical characteristics, suggesting that fibromyalgia rather than being related specifically to depression is related to bipolar spectrum disorders and in particular to the hypomania/overactivity component.

  11. Bipolar disorder and substance use disorders. Madrid study on the prevalence of dual disorders/pathology.

    PubMed

    Arias, Francisco; Szerman, Nestor; Vega, Pablo; Mesías, Beatriz; Basurte, Ignacio; Rentero, David

    2017-06-28

    Given its prevalence and impact on public health, the comorbidity of bipolar and substance use disorders is one of the most relevant of dual diagnoses. The objective was to evaluate the characteristics of patients from community mental health and substance abuse centres in Madrid. The sample consisted of 837 outpatients from mental health and substance abuse centres. We used the Mini International Neuropsychiatric Interview (MINI) and Personality Disorder Questionnaire (PDQ4+) to evaluate axis I and II disorders. Of these patients, 174 had a lifetime bipolar disorder, 83 had bipolar disorder type I and 91 had type II. Most patients had dual pathology. Of the 208 participants from the mental health centres, 21 had bipolar disorder and 13 (61.9%) were considered dually-diagnosed patients, while 33.2% of non-bipolar patients had a dual diagnoses (p = 0.03). Of the 629 participants from the substance abuse centres, 153 patients (24.3%) had a bipolar diagnosis. Bipolar dual patients had higher rates of alcohol and cocaine dependence than non-bipolar patients. Moreover, age at onset of alcohol use was earlier in bipolar duallydiagnosed patients than in other alcoholics. Bipolar dually-diagnosed patients had higher personality and anxiety disorder comorbidities and greater suicide risk. Thus, alcohol and cocaine are the drugs most associated with bipolar disorder. Given the nature of the study, the type of relationship between these disorders cannot be determined.

  12. General analytical approach for sound transmission loss analysis through a thick metamaterial plate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Oudich, Mourad; Zhou, Xiaoming; Badreddine Assouar, M., E-mail: Badreddine.Assouar@univ-lorraine.fr

    We report theoretically and numerically on the sound transmission loss performance through a thick plate-type acoustic metamaterial made of spring-mass resonators attached to the surface of a homogeneous elastic plate. Two general analytical approaches based on plane wave expansion were developed to calculate both the sound transmission loss through the metamaterial plate (thick and thin) and its band structure. The first one can be applied to thick plate systems to study the sound transmission for any normal or oblique incident sound pressure. The second approach gives the metamaterial dispersion behavior to describe the vibrational motions of the plate, which helpsmore » to understand the physics behind sound radiation through air by the structure. Computed results show that high sound transmission loss up to 72 dB at 2 kHz is reached with a thick metamaterial plate while only 23 dB can be obtained for a simple homogeneous plate with the same thickness. Such plate-type acoustic metamaterial can be a very effective solution for high performance sound insulation and structural vibration shielding in the very low-frequency range.« less

  13. Virginia Woolf, neuroprogression, and bipolar disorder.

    PubMed

    Boeira, Manuela V; Berni, Gabriela de Á; Passos, Ives C; Kauer-Sant'Anna, Márcia; Kapczinski, Flávio

    2017-01-01

    Family history and traumatic experiences are factors linked to bipolar disorder. It is known that the lifetime risk of bipolar disorder in relatives of a bipolar proband are 5-10% for first degree relatives and 40-70% for monozygotic co-twins. It is also known that patients with early childhood trauma present earlier onset of bipolar disorder, increased number of manic episodes, and more suicide attempts. We have recently reported that childhood trauma partly mediates the effect of family history on bipolar disorder diagnosis. In light of these findings from the scientific literature, we reviewed the work of British writer Virginia Woolf, who allegedly suffered from bipolar disorder. Her disorder was strongly related to her family background. Moreover, Virginia Woolf was sexually molested by her half siblings for nine years. Her bipolar disorder symptoms presented a pernicious course, associated with hospitalizations, suicidal behavioral, and functional impairment. The concept of neuroprogression has been used to explain the clinical deterioration that takes places in a subgroup of bipolar disorder patients. The examination of Virgina Woolf's biography and art can provide clinicians with important insights about the course of bipolar disorder.

  14. Nuclear reactor fuel structure containing uranium alloy wires embedded in a metallic matrix plate

    DOEpatents

    Travelli, A.

    1985-10-25

    A flat or curved plate structure, to be used as fuel in a nuclear reactor, comprises elongated fissionable wires or strips embedded in a metallic continuous non-fissionable matrix plate. The wires or strips are made predominantly of a malleable uranium alloy, such as uranium silicide, uranium gallide or uranium germanide. The matrix plate is made predominantly of aluminum or an aluminum alloy. The wires or strips are located in a single row at the midsurface of the plate, parallel with one another and with the length dimension of the plate. The wires or strips are separated from each other, and from the surface of the plate, by sufficient thicknesses of matrix material, to provide structural integrity and effective fission product retention, under neutron irradiation. This construction makes it safely feasible to provide a high uranium density, so that the uranium enrichment with uranium 235 may be reduced below about 20%, to deter the reprocessing of the uranium for use in nuclear weapons.

  15. Nuclear reactor fuel structure containing uranium alloy wires embedded in a metallic matrix plate

    DOEpatents

    Travelli, Armando

    1988-01-01

    A flat or curved plate structure, to be used as fuel in a nuclear reactor, comprises elongated fissionable wires or strips embedded in a metallic continuous non-fissionable matrix plate. The wires or strips are made predominantly of a malleable uranium alloy, such as uranium silicide, uranium gallide or uranium germanide. The matrix plate is made predominantly of aluminum or an aluminum alloy. The wires or strips are located in a single row at the midsurface of the plate, parallel with one another and with the length dimension of the plate. The wires or strips are separated from each other, and from the surface of the plate, by sufficient thicknesses of matrix material, to provide structural integrity and effective fission product retention, under neutron irradiation. This construction makes it safely feasible to provide a high uranium density, so that the uranium enrichment with uranium 235 may be reduced below about 20%, to deter the reprocessing of the uranium for use in nuclear weapons.

  16. Impacting load control of floating supported friction plate and its experimental verification

    NASA Astrophysics Data System (ADS)

    Ning, Keyan; Wang, Yu; Huang, Dingchuan; Yin, Lei

    2017-05-01

    Friction plates are key components in automobile transmission system. Unfortunately, due to the tough working condition i.e. high impact, high temperature, fracture and plastic deformation are easily observed in friction plates. In order to reduce the impact load and increase the impact resistance and life span of the friction plate. This paper presents a variable damping design method and structure, by punching holes in the key position of the friction plate and filling it with damping materials, the impact load of the floating support friction plate can be controlled. Simulation is applied to study the effect of the position and number of damping holes on tooth root stress. Furthermore, physic test was designed and conducted to validate the correctness and effectiveness of the proposed method. Test result shows that the impact load of the new structure is reduced by 40% and its fatigue life is 4.7 times larger. The new structure provides a new way for floating supported friction plates design.

  17. A Simplified Model for the Effect of Weld-Induced Residual Stresses on the Axial Ultimate Strength of Stiffened Plates

    NASA Astrophysics Data System (ADS)

    Chen, Bai-Qiao; Guedes Soares, C.

    2018-03-01

    The present work investigates the compressive axial ultimate strength of fillet-welded steel-plated ship structures subjected to uniaxial compression, in which the residual stresses in the welded plates are calculated by a thermo-elasto-plastic finite element analysis that is used to fit an idealized model of residual stress distribution. The numerical results of ultimate strength based on the simplified model of residual stress show good agreement with those of various methods including the International Association of Classification Societies (IACS) Common Structural Rules (CSR), leading to the conclusion that the simplified model can be effectively used to represent the distribution of residual stresses in steel-plated structures in a wide range of engineering applications. It is concluded that the widths of the tension zones in the welded plates have a quasi-linear behavior with respect to the plate slenderness. The effect of residual stress on the axial strength of the stiffened plate is analyzed and discussed.

  18. Optimization of an integrated electrodisinfection/electrocoagulation process with Al bipolar electrodes for urban wastewater reclamation.

    PubMed

    Cotillas, Salvador; Llanos, Javier; Cañizares, Pablo; Mateo, Sara; Rodrigo, Manuel A

    2013-04-01

    In this work, a novel integrated electrochemical process for urban wastewater regeneration is described. The electrochemical cell consists in a Boron Doped Diamond (BDD) or a Dimensionally Stable Anode (DSA) as anode, a Stainless Steel (SS) as cathode and a perforated aluminum plate, which behaves as bipolar electrode, between anode and cathode. Thus, in this cell, it is possible to carry out, at the same time, two different electrochemical processes: electrodisinfection (ED) and electrocoagulation (EC). The treatment of urban wastewater with different anodes and different operating conditions is studied. First of all, in order to check the process performance, experiments with synthetic wastewaters were carried out, showing that it is possible to achieve a 100% of turbidity removal by the electrodissolution of the bipolar electrode. Next, the effect of the current density and the anode material are studied during the ED-EC process of actual effluents. Results show that it is possible to remove Escherichia coli and turbidity simultaneously of an actual effluent from a WasteWater Treatment Facility (WWTF). The use of BDD anodes allows to remove the E. coli completely at an applied electric charge of 0.0077 A h dm(-3) when working with a current density of 6.65 A m(-2). On the other hand, with DSA anodes, the current density necessary to achieve the total removal of E. coli is higher (11.12 A m(-2)) than that required with BDD anodes. Finally, the influence of cell flow path and flow rate have been studied. Results show that the performance of the process strongly depends on the characteristics of the initial effluent (E. coli concentration and Cl(-)/NH(4)(+) initial ratio) and that a cell configuration cathode (inlet)-anode (outlet) and a higher flow rate enhance the removal of the turbidity from the treated effluent. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Multi-objective shape optimization of plate structure under stress criteria based on sub-structured mixed FEM and genetic algorithms

    NASA Astrophysics Data System (ADS)

    Garambois, Pierre; Besset, Sebastien; Jézéquel, Louis

    2015-07-01

    This paper presents a methodology for the multi-objective (MO) shape optimization of plate structure under stress criteria, based on a mixed Finite Element Model (FEM) enhanced with a sub-structuring method. The optimization is performed with a classical Genetic Algorithm (GA) method based on Pareto-optimal solutions and considers thickness distributions parameters and antagonist objectives among them stress criteria. We implement a displacement-stress Dynamic Mixed FEM (DM-FEM) for plate structure vibrations analysis. Such a model gives a privileged access to the stress within the plate structure compared to primal classical FEM, and features a linear dependence to the thickness parameters. A sub-structuring reduction method is also computed in order to reduce the size of the mixed FEM and split the given structure into smaller ones with their own thickness parameters. Those methods combined enable a fast and stress-wise efficient structure analysis, and improve the performance of the repetitive GA. A few cases of minimizing the mass and the maximum Von Mises stress within a plate structure under a dynamic load put forward the relevance of our method with promising results. It is able to satisfy multiple damage criteria with different thickness distributions, and use a smaller FEM.

  20. Vibration of functionally graded plate resting on viscoelastic elastic foundation subjected to moving loads

    NASA Astrophysics Data System (ADS)

    Duy Hien, Ta; Lam, Nguyen Ngoc

    2018-04-01

    The dynamics of plates subjected to a moving load must be considered by engineering mechanics and design structures. This paper deals with the dynamic responses of functionally graded (FG) rectangular plates resting on a viscoelastic foundation under moving loads. It is assumed that material properties of the plate vary continuously in the thickness direction according to the power-law. The governing equations are derived by using Hamilton’s principle, which considers the effect of the higher-order shear deformation in the plate. Transient responses of simply supported FG rectangular plates are employed by using state-space methods. Several examples are given for displacement and stresses in the plates with various structural parameters, and the effects of these parameters are discussed.

  1. Bipolar disorder in adolescence.

    PubMed

    DeFilippis, Melissa; Wagner, Karen Dineen

    2013-08-01

    Bipolar disorder is a serious psychiatric condition that may have onset in childhood. It is important for physicians to recognize the symptoms of bipolar disorder in children and adolescents in order to accurately diagnose this illness early in its course. Evidence regarding the efficacy of various treatments is necessary to guide the management of bipolar disorder in youth. For example, several medications commonly used for adults with bipolar disorder have not shown efficacy for children and adolescents with bipolar disorder. This article reviews the prevalence, diagnosis, course, and treatment of bipolar disorder in children and adolescents and provides physicians with information that will aid in diagnosis and treatment.

  2. Differential diagnosis of bipolar disorder and major depressive disorder.

    PubMed

    Hirschfeld, R M

    2014-12-01

    Patients with bipolar disorder spend approximately half of their lives symptomatic and the majority of that time suffering from symptoms of depression, which complicates the accurate diagnosis of bipolar disorder. Challenges in the differential diagnosis of bipolar disorder and major depressive disorder are reviewed, and the clinical utility of several screening instruments is evaluated. The estimated lifetime prevalence of major depressive disorder (i.e., unipolar depression) is over 3 and one-half times that of bipolar spectrum disorders. The clinical presentation of a major depressive episode in a bipolar disorder patient does not differ substantially from that of a patient with major depressive disorder (unipolar depression). Therefore, it is not surprising that without proper screening and comprehensive evaluation many patients with bipolar disorder may be misdiagnosed with major depressive disorder (unipolar depression). In general, antidepressants have demonstrated little or no efficacy for depressive episodes associated with bipolar disorder, and treatment guidelines recommend using antidepressants only as an adjunct to mood stabilizers for patients with bipolar disorder. Thus, correct identification of bipolar disorder among patients who present with depression is critical for providing appropriate treatment and improving patient outcomes. Clinical characteristics indicative of bipolar disorder versus major depressive disorder identified in this review are based on group differences and may not apply to each individual patient. The overview of demographic and clinical characteristics provided by this review may help medical professionals distinguish between major depressive disorder and bipolar disorder. Several validated, easily administered screening instruments are available and can greatly improve the recognition of bipolar disorder in patients with depression. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Bipolar plating of metal contacts onto oxide interconnection for solid oxide electrochemical cell

    DOEpatents

    Isenberg, A.O.

    1987-03-10

    Disclosed is a method of forming an adherent metal deposit on a conducting layer of a tube sealed at one end. The tube is immersed with the sealed end down into an aqueous solution containing ions of the metal to be deposited. An ionically conducting aqueous fluid is placed inside the tube and a direct current is passed from a cathode inside the tube to an anode outside the tube. Also disclosed is a multi-layered solid oxide fuel cell tube which consists of an inner porous ceramic support tube, a porous air electrode covering the support tube, a non-porous electrolyte covering a portion of the air electrode, a non-porous conducting interconnection covering the remaining portion of the electrode, and a metal deposit on the interconnection. 1 fig.

  4. Bipolar plating of metal contacts onto oxide interconnection for solid oxide electrochemical cell

    DOEpatents

    Isenberg, Arnold O.

    1987-01-01

    Disclosed is a method of forming an adherent metal deposit on a conducting layer of a tube sealed at one end. The tube is immersed with the sealed end down into an aqueous solution containing ions of the metal to be deposited. An ionically conducting aqueous fluid is placed inside the tube and a direct current is passed from a cathode inside the tube to an anode outside the tube. Also disclosed is a multi-layered solid oxide fuel cell tube which consists of an inner porous ceramic support tube, a porous air electrode covering the support tube, a non-porous electrolyte covering a portion of the air electrode, a non-porous conducting interconnection covering the remaining portion of the electrode, and a metal deposit on the interconnection.

  5. Further Evidence for Robust Familiality of Pediatric Bipolar-I Disorder: Results from a Very Large Controlled Family Study of Pediatric Bipolar-I Disorder and a Meta-Analysis

    PubMed Central

    Wozniak, Janet; Faraone, Stephen V.; Martelon, MaryKate; McKillop, Hannah N.; Biederman, Joseph

    2013-01-01

    Objective To determine the risk for BP-I disorder in first-degree relatives of children with DSM-IV bipolar-I disorder (BP-I) via meta-analysis and expanded controlled study. Data Sources and Extraction Meta-Analysis We searched the Pubmed database for scientific articles published in the world literature in the English language through 2011. The key words searched were: bipolar disorder, first-degree relatives, family study, control. All online abstracts were reviewed and relevant full manuscripts were collected and reviewed. Citations were also examined for other potential relevant articles. We included only controlled family studies that examined rates of bipolar-I disorder in all first-degree relatives (parents and siblings) of pediatric bipolar-I probands and included only studies that had age and sex matched controls. Family history studies were excluded. Also excluded were studies that were not in English, did not report the rates of all first-degree relatives, and reported only bipolar spectrum rates. We also excluded family studies that included only adult probands. We conducted a meta-analysis of the five controlled family studies of pediatric BP-I probands that met our search criteria using the random effects model of DerSimonian and Laird. Method Family Study We greatly expanded our previous sample of DSM-IV BP-I probands using structured diagnostic interviews. Our new study included 239 children satisfying full with DSM-IV diagnostic criteria for BP-I (n=726 first-degree relatives), 162 ADHD (without BP-I) probands (n=511 first-degree relatives), and 136 healthy control (without ADHD or BP-I) probands (n=411 first-degree relatives). We used the Kaplan-Meier cumulative failure function to calculate survival curves and cumulative, lifetime risk in relatives. Cox proportional hazard models were used to calculate the risk of BP-I in relatives. Results The pooled odds ratio for BP-I disorder in relatives was estimated to be 6.96 (95% Confidence Interval (CI): 4.8 to 10.1). We also found first-degree relatives of BP-I probands to be significantly more likely than first-degree relatives of both ADHD (Hazards Ratio: 3.02; 95% CI: 1.85 to 4.93; p<0.001) and control probands (HR: 2.83; 1.65 to 4.84; p<0.001) to have bipolar-I disorder. Conclusion Our results document an increased familial risk for BP-I disorder in relatives of pediatric probands with DSM-IV BP-I. PMID:23140652

  6. Relationship between Chinese adjective descriptors of personality and emotional symptoms in young Chinese patients with bipolar disorders.

    PubMed

    Yu, Enyan; Li, Huihui; Fan, Hongying; Gao, Qianqian; Tan, Yunfei; Lou, Junyao; Zhang, Jie; Wang, Wei

    2015-12-01

    To investigate whether personality traits are related to emotional symptoms (mania, hypomania, and depression) in Chinese patients with bipolar disorders. Patients with bipolar I and II disorders, and healthy volunteers, were assessed using the Chinese Adjective Descriptors of Personality (CADP) questionnaire, Mood Disorder Questionnaire (MDQ), Hypomanic Checklist (HCL-32), and Plutchik-van Praag Depression Inventory (PVP). Seventy-three patients with bipolar I disorder, 35 with bipolar II disorder and 216 healthy controls were included. Bipolar I and II groups scored significantly higher on MDQ, HCL-32 and PVP scales than controls; the bipolar II group scored lower on the MDQ, but higher on the HCL-32 and PVP than bipolar I. In the bipolar I group, the CADP Intelligent trait (β, 0.25) predicted MDQ; Intelligent (β, -0.24), Agreeable (β, 0.22) and Emotional (β, 0.34) traits predicted PVP. In the bipolar II group, Intelligent (β, 0.22), Agreeable (β, -0.24) and Unsocial (β, 0.31) traits predicted MDQ; Intelligent (β, -0.20), Agreeable (β, -0.31) and Emotional (β, -0.26) traits predicted HCL-32. Four out of five Chinese personality traits were associated with emotional symptoms in patients with bipolar I or II disorder, but displayed different associations depending on disorder type. © The Author(s) 2015.

  7. [Recurrences of bipolar disorders - comparative study of bipolar disorders, recurring depressions and single depressions in a cohort of patients aged over 65 years].

    PubMed

    Galland, F; Vaille-Perret, E; Gerbaud, L; Jalenques, I

    2007-09-01

    Bipolar mood disorders, after starting at adulthood, may remain active throughout life, but bipolar disorders may only be revealed in later life. Indeed, Yet few data on bipolar disorders in the elderly have been reported in the litterature. The influence of normal aging on the outcome of the disease as well as the specific prognosis of bipolar disorders in the elderly has occasionally been studied. Eventually Finally, and contrasting with adults, few studies comparing the various subtypes of mood disorders were have been performed in the elderly. We therefore developed a study in patients aged 65 or above, in order to evaluate the course (recurrences) of bipolar disorders, compared to recurring depressions and single depressions, and to determine the influence of recurrences on the outcome of bipolar disorders. Patients aged over 65 years were inpatients admitted to the department of psychiatry in 2000 for one of the three previously mentioned diagnoses according to DSM IV. Retrospective data were collected from medical reports. Prospectively, data were collected from the general practitioner of each patient (relying on telephone calls), before statistical analysis was performed. Our study demonstrates a more severe outcome for bipolar disorders compared to recurring depressions and single depressions. Patients with bipolar disorders have a higher prevalence of psychiatric recurrences. Furthermore, the greater the number of previous relapses (or the longer the duration and intensity of the disease), the higher the risk of future new future recurrences both in bipolar disorders and recurring depressions. An age of onset of bipolar disorders before 60 years and more than 5 in-hospital admissions increase the risk of recurrences. We originally compare the outcome of bipolar disorders in the elderly, to recurring depressions and single depressions. We confirm the fatal outcome of recurrences in bipolar disorders in old age. Bipolar disorders in the elderly should be considered as a real public health care problem: strategies to minimize the number of episodes experienced by patients with bipolar illness must be pursued aggressively throughout life.

  8. Impairment in emotion perception from body movements in individuals with bipolar I and bipolar II disorder is associated with functional capacity.

    PubMed

    Vaskinn, Anja; Lagerberg, Trine Vik; Bjella, Thomas D; Simonsen, Carmen; Andreassen, Ole A; Ueland, Torill; Sundet, Kjetil

    2017-12-01

    Individuals with bipolar disorder present with moderate impairments in social cognition during the euthymic state. The impairment extends to theory of mind and to the perception of emotion in faces and voices, but it is unclear if emotion perception from body movements is affected. The main aim of this study was to examine if participants with bipolar disorder perform worse than healthy control participants on a task using point-light displays of human full figures moving in a manner indicative of a basic emotion (angry, happy, sad, fearful, neutral/no emotion). A secondary research question was whether diagnostic subtypes (bipolar I, bipolar II) and history of psychosis impacted on this type of emotion perception. Finally, symptomatic, neurocognitive, and functional correlates of emotion perception from body movements were investigated. Fifty-three individuals with bipolar I (n = 29) or bipolar II (n = 24) disorder, and 84 healthy control participants were assessed for emotion perception from body movements. The bipolar group also underwent clinical, cognitive, and functional assessment. Research questions were analyzed using analyses of variance and bivariate correlations. The bipolar disorder group differed significantly from healthy control participants for emotion perception from body movements (Cohen's d = 0.40). Analyses of variance yielded no effects of sex, diagnostic subtype (bipolar I, bipolar II), or history of psychosis. There was an effect of emotion, indicating that some emotions are easier to recognize. The lack of a significant group × emotion interaction effect points, however, to this being so regardless of the presence of bipolar disorder. Performance was unrelated to manic and depressive symptom load but showed significant associations with neurocognition and functional capacity. Individuals with bipolar disorder had a small but significant impairment in the ability to perceive emotions from body movement. The impairment was global, i.e., affecting all emotions and equally present for males and females. The impairment was associated with neurocognition and functional capacity, but not symptom load. Our findings identify pathopsychological factors underlying the functional impairment in bipolar disorder and suggest the consideration of social cognition training as part of the treatment for bipolar disorder.

  9. Variable waveband infrared imager

    DOEpatents

    Hunter, Scott R.

    2013-06-11

    A waveband imager includes an imaging pixel that utilizes photon tunneling with a thermally actuated bimorph structure to convert infrared radiation to visible radiation. Infrared radiation passes through a transparent substrate and is absorbed by a bimorph structure formed with a pixel plate. The absorption generates heat which deflects the bimorph structure and pixel plate towards the substrate and into an evanescent electric field generated by light propagating through the substrate. Penetration of the bimorph structure and pixel plate into the evanescent electric field allows a portion of the visible wavelengths propagating through the substrate to tunnel through the substrate, bimorph structure, and/or pixel plate as visible radiation that is proportional to the intensity of the incident infrared radiation. This converted visible radiation may be superimposed over visible wavelengths passed through the imaging pixel.

  10. On 3D flow-structures behind an inclined plate

    NASA Astrophysics Data System (ADS)

    Uruba, Václav; Pavlík, David; Procházka, Pavel; Skála, Vladislav; Kopecký, Václav

    Stereo PIV measurements has been performed behind the inclined plate, angle of attack 5 and 10 deg. Occurrence and dynamics of streamwise structures behind the plate trailing edge have been studied in details using POD method. The streamwise structures are represented by vortices and low- and highvelocity regions, probably streaks. The obtained results support the hypothesis of an airfoil-flow force interaction by Hoffman and Johnson [1,2].

  11. Circumstellar Structure Properties of Young Stellar Objects: Envelopes, Bipolar Outflows, and Disks

    NASA Astrophysics Data System (ADS)

    Kwon, Woojin

    2009-12-01

    Physical properties of the three main structures in young stellar objects (YSOs), envelopes, bipolar outflows, and circumstellar disks, have been studied using radio interferometers: the Berkeley-Illinois-Maryland Association (BIMA) array and the Combined Array for Research in Millimeter-wave Astronomy (CARMA). (1) Envelopes. Three Class 0 YSOs (L1448 IRS 2, L1448 IRS 3, and L1157) have been observed by CARMA at λ = 1.3 mm and 2.7 mm continuum. Through visibility modeling to fit the two wavelength continuum data simultaneously, we found that the dust opacity spectral index (β) of Class 0 YSOs is around unity, which implies that dust grains have significantly grown already at the earliest stage. In addition, we discussed the radial dependence of β detected in L1448 IRS 3B and also estimated the density distribution of the three targets. (2) Bipolar outflows. Polarimetric observations in the λ = 1.3 mm continuum and CO, as well as spectral line observations in 13CO and C18O have been carried out toward L1448 IRS 3, which has three Class 0 YSOs, using BIMA. We clearly identified two interacting bipolar outflows from the "binary system" of IRS 3A and 3B and estimated the velocity, inclination, and opening angle of the 3B bipolar outflow, using Bayesian inference. Also, we showed that the "binary system" can be bound gravitationally and we estimated the specific angular momentum, which is between those of binary stars and molecular cloud cores. In addition, we marginally detected linear polarizations at the center of IRS 3B (implying a toroidal magnetic field) in continuum and at the bipolar outflow region in CO. (3) Circumstellar disks. We present the results of 6 objects (CI Tau, DL Tau, DO Tau, FT Tau, Haro 6-13, and HL Tau) in our T Tauri disk survey using CARMA. The data consist of λ = 1.3 mm and 2.7 mm continuum with an angular resolution up to 0.13". Through visibility modeling of two disk models (power-law disk with a Gaussian edge and viscous accretion disk) to fit the two wavelength data simultaneously in Bayesian inference, we constrained disk properties. In addition, we detected a dust lane at 100 AU radius of HL Tau, which is gravitationally unstable and can be fragmented. Besides, CI Tau and DL Tau appear to have a spiral pattern. Moreover, we found that more evolved disks have a shallower density gradient and that disks with a smaller β are less massive, which implies "hidden" masses in the cold midplane and/or in large grains. Finally, we found that the accretion disk model is preferred by HL Tau, which has a strong bipolar outflow and accretion, while the power-law disk model is preferred by DL Tau, which has experienced dust settlement and has weak accretion. This implies that the accretion disk model could be applied to disks only in a limited age range.

  12. Course of Subthreshold Bipolar Disorder in Youth: Diagnostic Progression from Bipolar Disorder Not Otherwise Specified

    ERIC Educational Resources Information Center

    Axelson, David A.; Birmaher, Boris; Strober, Michael A.; Goldstein, Benjamin I.; Ha, Wonho; Gill, Mary Kay; Goldstein, Tina R.; Yen, Shirley; Hower, Heather; Hunt, Jeffrey I.; Liao, Fangzi; Iyengar, Satish; Dickstein, Daniel; Kim, Eunice; Ryan, Neal D.; Frankel, Erica; Keller, Martin B.

    2011-01-01

    Objective: To determine the rate of diagnostic conversion from an operationalized diagnosis of bipolar disorder not otherwise specified (BP-NOS) to bipolar I disorder (BP-I) or bipolar II disorder (BP-II) in youth over prospective follow-up and to identify factors associated with conversion. Method: Subjects were 140 children and adolescents…

  13. Bipolar Disorder.

    PubMed

    Miller, Thomas H

    2016-06-01

    Bipolar disorder is a chronic mental health disorder that is frequently encountered in primary care. Many patients with depression may actually have bipolar disorder. The management of bipolar disorder requires proper diagnosis and awareness or referral for appropriate pharmacologic therapy. Patients with bipolar disorder require primary care management for comorbidities such as cardiovascular and metabolic disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. The cross-national structure of mental disorders: results from the World Mental Health Surveys.

    PubMed

    de Jonge, Peter; Wardenaar, Klaas J; Lim, Carmen C W; Aguilar-Gaxiola, Sergio; Alonso, Jordi; Andrade, Laura Helena; Bunting, Brendan; Chatterji, Somnath; Ciutan, Marius; Gureje, Oye; Karam, Elie G; Lee, Sing; Medina-Mora, Maria Elena; Moskalewicz, Jacek; Navarro-Mateu, Fernando; Pennell, Beth-Ellen; Piazza, Marina; Posada-Villa, José; Torres, Yolanda; Kessler, Ronald C; Scott, Kate

    2017-12-19

    The patterns of comorbidity among mental disorders have led researchers to model the underlying structure of psychopathology. While studies have suggested a structure including internalizing and externalizing disorders, less is known with regard to the cross-national stability of this model. Moreover, little data are available on the placement of eating disorders, bipolar disorder and psychotic experiences (PEs) in this structure. We evaluated the structure of mental disorders with data from the World Health Organization Composite International Diagnostic Interview, including 15 lifetime mental disorders and six PEs. Respondents (n = 5478-15 499) were included from 10 high-, middle- and lower middle-income countries across the world aged 18 years or older. Confirmatory factor analyses (CFAs) were used to evaluate and compare the fit of different factor structures to the lifetime disorder data. Measurement invariance was evaluated with multigroup CFA (MG-CFA). A second-order model with internalizing and externalizing factors and fear and distress subfactors best described the structure of common mental disorders. MG-CFA showed that this model was stable across countries. Of the uncommon disorders, bipolar disorder and eating disorder were best grouped with the internalizing factor, and PEs with a separate factor. These results indicate that cross-national patterns of lifetime common mental-disorder comorbidity can be explained with a second-order underlying structure that is stable across countries and can be extended to also cover less common mental disorders.

  15. Numerical analysis of the vibroacoustic properties of plates with embedded grids of acoustic black holes.

    PubMed

    Conlon, Stephen C; Fahnline, John B; Semperlotti, Fabio

    2015-01-01

    The concept of an Acoustic Black Hole (ABH) has been developed and exploited as an approach for passively attenuating structural vibration. The basic principle of the ABH relies on proper tailoring of the structure geometrical properties in order to produce a gradual reduction of the flexural wave speed, theoretically approaching zero. For practical systems the idealized "zero" wave speed condition cannot be achieved so the structural areas of low wave speed are treated with surface damping layers to allow the ABH to approach the idealized dissipation level. In this work, an investigation was conducted to assess the effects that distributions of ABHs embedded in plate-like structures have on both vibration and structure radiated sound, focusing on characterizing and improving low frequency performance. Finite Element and Boundary Element models were used to assess the vibration response and radiated sound power performance of several plate configurations, comparing baseline uniform plates with embedded periodic ABH designs. The computed modal loss factors showed the importance of the ABH unit cell low order modes in the overall vibration reduction effectiveness of the embedded ABH plates at low frequencies where the free plate bending wavelengths are longer than the scale of the ABH.

  16. Anatomical Thin Titanium Mesh Plate Structural Optimization for Zygomatic-Maxillary Complex Fracture under Fatigue Testing.

    PubMed

    Wang, Yu-Tzu; Huang, Shao-Fu; Fang, Yu-Ting; Huang, Shou-Chieh; Cheng, Hwei-Fang; Chen, Chih-Hao; Wang, Po-Fang; Lin, Chun-Li

    2018-01-01

    This study performs a structural optimization of anatomical thin titanium mesh (ATTM) plate and optimal designed ATTM plate fabricated using additive manufacturing (AM) to verify its stabilization under fatigue testing. Finite element (FE) analysis was used to simulate the structural bending resistance of a regular ATTM plate. The Taguchi method was employed to identify the significance of each design factor in controlling the deflection and determine an optimal combination of designed factors. The optimal designed ATTM plate with patient-matched facial contour was fabricated using AM and applied to a ZMC comminuted fracture to evaluate the resting maxillary micromotion/strain under fatigue testing. The Taguchi analysis found that the ATTM plate required a designed internal hole distance to be 0.9 mm, internal hole diameter to be 1 mm, plate thickness to be 0.8 mm, and plate height to be 10 mm. The designed plate thickness factor primarily dominated the bending resistance up to 78% importance. The averaged micromotion (displacement) and strain of the maxillary bone showed that ZMC fracture fixation using the miniplate was significantly higher than those using the AM optimal designed ATTM plate. This study concluded that the optimal designed ATTM plate with enough strength to resist the bending effect can be obtained by combining FE and Taguchi analyses. The optimal designed ATTM plate with patient-matched facial contour fabricated using AM provides superior stabilization for ZMC comminuted fractured bone segments.

  17. Bipolar disorder: diagnostic issues.

    PubMed

    Tiller, John W G; Schweitzer, Isaac

    2010-08-16

    Bipolar disorders are cyclical mood disorders with clinical features including distinct sustained periods of mood elevation. Briefer (4 days or more), mild episodes of mood elevation define bipolar II disorder; lengthier (7 days or more), more severe episodes (or those requiring hospitalisation), with or without psychotic features, define bipolar I disorder. Depressive periods are more common and lengthier than manic or hypomanic states, and are the main cause of disability. Bipolar depression may respond poorly to antidepressants and these medications may destabilise the illness. The diagnosis of bipolar disorder should be considered when a patient with depression is treatment resistant. Irritability is a common symptom in bipolar disorder, particularly during mixed states (during which patients have features of mood elevation and depression concurrently) or when there is rapid cycling of mood (more than four episodes of mood disorder per year). Alcohol misuse and use of illicit drugs may simulate mood changes in bipolar disorder. Accurate diagnosis and assessment of bipolar disorder is essential for clinical decision making and determining prognosis and treatments.

  18. Effect of Plate Curvature on Blast Response of Structural Steel Plates

    NASA Astrophysics Data System (ADS)

    Veeredhi, Lakshmi Shireen Banu; Ramana Rao, N. V.; Veeredhi, Vasudeva Rao

    2018-04-01

    In the present work an attempt is made, through simulation studies, to determine the effect of plate curvature on the blast response of a door structure made of ASTM A515 grade 50 steel plates. A door structure with dimensions of 5.142 m × 2.56 m × 10 mm having six different radii of curvatures is analyzed which is subjected to blast load. The radii of curvature investigated are infinity (flat plate), 16.63, 10.81, 8.26, 6.61 and 5.56 m. In the present study, a stand-off distance of 11 m is considered for all the cases. Results showed that the door structure with smallest radius of curvature experienced least plastic deformation and yielding when compared to a door with larger radius of curvature with same projected area. From the present Investigation, it is observed that, as the radius of curvature of the plate increases, the deformation mode gradually shifts from indentation mode to flexural mode. The plates with infinity and 16.63 m radius of curvature have undergone flexural mode of deformation and plates with 6.61 and 5.56 m radius of curvature undergo indentation mode of deformation. Whereas, mixed mode of deformation that consists of both flexural and indentation mode of deformations are seen in the plates with radius of curvature 10.81 and 8.26 m. As the radius of curvature of the plate decreases the ability of the plate to mitigate the effect the blast loads increased. It is observed that the plate with smaller radius of curvature deflects most of the blast energy and results in least indentation mode of deformation. The most significant observation made in the present investigation is that the strain energy absorbed by the steel plate gets reduced to 1/3 rd when the radius of curvature is approximately equal to the stand-off distance which could be the critical radius of curvature.

  19. The Effect of Personalized Guideline-Concordant Treatment on Quality of Life and Functional Impairment in Bipolar Disorder

    PubMed Central

    Sylvia, Louisa G.; Rabideau, Dustin J.; Nierenberg, Andrew A.; Bowden, Charles L.; Friedman, Edward S.; Iosifescu, Dan V.; Thase, Michael E.; Ketter, Terence; Greiter, Elizabeth A.; Calabrese, Joseph R.; Leon, Andrew C.; Ostacher, Michael J.; Reilly-Harrington, Noreen

    2014-01-01

    Objectives The aims of this study were to evaluate correlates and predictors of life functioning and quality of life in bipolar disorder during a comparative effectiveness trial of moderate doses of lithium. Methods In the Lithium treatment moderate-dose use study (LiTMUS), 283 symptomatic outpatients with bipolar disorder type I or II were randomized to receive lithium plus ”optimal personalized treatment (OPT), or OPT alone. Participants were assessed using structured diagnostic interviews, clinician-rated blinded assessments, and questionnaires. We employ linear mixed effects models to test the effect of treatment overall and adjunct lithium specifically on quality of life or functioning. Similar models are used to examine the association of baseline demographics and clinical features with quality of life and life functioning. Results Quality of life and impaired functioning at baseline were associated with lower income, higher depressive severity, and more psychiatric comorbid conditions. Over six months, patients in both treatment groups improved in quality of life and life functioning (p-values < 0.0001); without a statistically significant difference between the two treatment groups (p-values > 0.05). Within the lithium group, improvement in quality of life and functioning were not associated with concurrent lithium levels at week 12 or week 24 (p-values > 0.05). Lower baseline depressive severity and younger age of onset predicted less improvement in functioning over six months. Conclusions Optimized care for bipolar disorder improves overall quality of life and life functioning, with no additional benefit from adjunct moderate doses of lithium. Illness burden and psychosocial stressors were associated with worse quality of life and lower functioning in individuals with bipolar disorder. PMID:25194782

  20. Global brain connectivity alterations in patients with schizophrenia and bipolar spectrum disorders.

    PubMed

    Skåtun, Kristina C; Kaufmann, Tobias; Tønnesen, Siren; Biele, Guido; Melle, Ingrid; Agartz, Ingrid; Alnæs, Dag; Andreassen, Ole A; Westlye, Lars T

    2016-08-01

    The human brain is organized into functionally distinct modules of which interactions constitute the human functional connectome. Accumulating evidence has implicated perturbations in the patterns of brain connectivity across a range of neurologic and neuropsychiatric disorders, but little is known about diagnostic specificity. Schizophrenia and bipolar disorders are severe mental disorders with partly overlapping symptomatology. Neuroimaging has demonstrated brain network disintegration in the pathophysiologies; however, to which degree the 2 diagnoses present with overlapping abnormalities remains unclear. We collected resting-state fMRI data from patients with schizophrenia or bipolar disorder and from healthy controls. Aiming to characterize connectivity differences across 2 severe mental disorders, we derived global functional connectivity using eigenvector centrality mapping, which allows for regional inference of centrality or importance in the brain network. Seventy-one patients with schizophrenia, 43 with bipolar disorder and 196 healthy controls participated in our study. We found significant effects of diagnosis in 12 clusters, where pairwise comparisons showed decreased global connectivity in high-centrality clusters: sensory regions in patients with schizophrenia and subcortical regions in both patient groups. Increased connectivity occurred in frontal and parietal clusters in patients with schizophrenia, with intermediate effects in those with bipolar disorder. Patient groups differed in most cortical clusters, with the strongest effects in sensory regions. Methodological concerns of in-scanner motion and the use of full correlation measures may make analyses more vulnerable to noise. Our results show decreased eigenvector centrality of limbic structures in both patient groups and in sensory regions in patients with schizophrenia as well as increased centrality in frontal and parietal regions in both groups, with stronger effects in patients with schizophrenia.

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