Sample records for bipolar transconductance amplifier

  1. Processing of Communication Signal Using Operational Transconductance Amplifier

    Roy, A; Mondal, S; Ray, B N


    This paper proposes a signal processing methodology of communication system and realized that circuits using operational transconductance amplifier (OTA). Two important classes of communication circuit, delta modulator and compander have been designed using that procedure. In the first implementation coded pulse modulation system is demonstrated which employ sampling, quantizing and coding to convert analog waveforms to digital signals while the second gives data compression and expansion in digital communication system. The proposed compander circuit is realized with operational transconductance amplifier and diode. Required power supply to operate the circuit is 3.5V. Performance of the circuits realized with OTAs has been demonstrated through SPICE simulation.

  2. An Electronically Tunable Transconductance Amplifier for Use in Auditory Prostheses

    FARAGO, P.


    Full Text Available Low-voltage and low-power trends in analog electronics enable novel features in modern bio-medical devices, such as extensive portability, autonomy and even battery-less operation. One specific example is the cochlear implant (CI, which emulates the physiology of hearing to produce auditory sensations via neural stimulation. Besides low-voltage and low-power operation, a key feature in modern CIs is wide-range programmability of the speech processing parameters. This paper proposes an operational transconductance amplifier (OTA for use in CIs, with wide-range electronic tuning of the transconductance value. The proposed OTA is developed around a cascade of two transconductor stages, making the transconductance dependent on the bias current ratio. A combination of linearization techniques: bulk input, parallel differential pairs and feedback, is used to achieve sufficient linear range for CI speech processing. Wide-range parameter tuning of the speech processing sections is illustrated on a variable gain amplifier, a bandpass Tow-Thomas biquad and an envelope detector. Finally, the complete CI speech processing chain is illustrated. The proposed OTA and its employment in CI analog speech processing are validated on a 350 nm CMOS process.

  3. Techniques for the Improvement in the Transconductance of a Bulk Driven Amplifier

    Kshitij Shant ,; Rita Mahajan


    This paper proposed methods for the improvement of transconductance in the bulk driven operation amplifier. Here we are using four technologies for the enhancement of transconductance. First modifies the transconductance with the help of active load; second uses a differential pair for the modification transconductance, while third is the proposed bulk-driven input stages with modified low voltage cascode biasing scheme whereas last is the bulk driven input stage with enhanced eff...

  4. Efficient Slew-Rate Enhanced Operational Transconductance Amplifier

    Xiao-Peng Wan; Fei-Xiang Zhang; Shao-Wei Zhen; Ya-Juan He; Ping Luo


    Abstract⎯Today, along with the prevalent use of portable equipment, wireless, and other battery powered systems, the demand for amplifiers with a high gain-bandwidth product (GBW), slew rate (SR), and at the same time very low static power dissipation is growing. In this work, an operational transconductance amplifier (OTA) with an enhanced SR is proposed. By inserting a sensing resistor in the input port of the current mirror in the OTA, the voltage drop across the resistor is converted into an output current containing a term in proportion to the square of the voltage, and then the SR of the proposed OTA is significantly enhanced and the current dissipation can be reduced. The proposed OTA is designed and simulated with a 0.5μm complementary metal oxide semiconductor (CMOS) process. The simulation results show that the SR is 4.54 V/μs, increased by 8.25 times than that of the conventional design, while the current dissipation is only 87.3%.

  5. Low-power, enhanced-gain adaptive-biasing-based Operational Transconductance Amplifiers

    Moradi, Farshad

    A symmetrical PMOS OTA (Operational Transconductance Amplifier) is used to build an advanced rail-to-rail amplifier with improved DC-gain and reduced power consumption. By using the adaptive biasing circuit for two differential inputs, a low stand-by current can be achieved, reducing power consum...

  6. An ultra-low voltage high gain operational transconductance amplifier for biomedical applications

    Bautista, F.; Martınez, S.O.; Dieck, G.; Rossetto, O.


    A novel differential-input single-output Operational Transconductance Amplifier (OTA) is presented in this paper. The topology proposed consists of an input stage based on a folded cascoded amplifier, and an output stage based on a current source amplifier and a bulk-driven current mirror. The simulations show that the amplifier has a 1.94¹W power dissipation, 92dB open-loop DC gain, a unit gain-bandwidth of 390KHz, a low noise between 537Hz to 390KHz and operates at 0.5V rail-to-rail supply ...

  7. An analog VLSI cochlea with new transconductance amplifiers and nonlinear gain control

    Sarpeshkar, Rahul; Lyon, Richard F.; Mead, Carver A.


    We show data from a working 45-stage analog VLSI cochlea, built on a 2.2 mm×2.2 mm tiny chip. The novel architectural features in this cochlea are: (1) The use of a wide-linear-range low-noise subthreshold transconductance amplifier. (2) The use of “fuse-like” nonlinear positive-feedback amplification in the second-order cochlear filter. Several new circuit techniques used in the design are described here. The fuse nonlinearity shuts off the positive-feedback amplification at large signal lev...

  8. Particle detector tunable monolithic Semi-Gaussian shaping filter based on transconductance amplifiers

    An IC semi-Gaussian shaper architecture for X-rays silicon strip detectors is presented. The specific structure is based on operational transconductance amplifiers (OTAs) and was implemented using an alternative design technique. The shaper was designed and fabricated in a 0.35 μm process by Austria Mikro Systeme and provides continuous variable operating bandwidth in a relatively low-frequency region, capability that indicates it as an optimum selection for a variety of readout applications. Analysis is supported by measurement results confirming the advantageous shaping filter performance. The circuit appears to be low power providing 530 μW power dissipation, while the output noise performance is 167 μV (rms) for an operating bandwidth of 260 kHz. Extensive experimental results concerning the total harmonic distortion and the dynamic range of the circuit also confirm its satisfactory performance

  9. Design of Biquad Universal Filter Using Operational Transconductance Amplifier in 180nm Technology

    Rahul Kumar,


    Full Text Available This paper presents concept of universal filter using operational transconductance amplifier (OTA.The 0.18μm CMOS process is used for design and simulation. This OTA has basing current of 50μA with supply voltage ±1.25v. The design and simulation of this OTA is done using CADENCE virtuoso environment with UMC 0.18μm technology file. This paper presents a electronically tunable voltage mode universal biquadratic filter with Three input and single output using two single ended OTA and two capacitors. The proposed filter provides low-pass,High-pass,Band-pass and Band-stop by appropriately connecting the input terminals. The natural frequency and the quality factor can be set orthogonally by adjusting the circuit components.Also the natural frequency can be electronically tuned via the bias currents of OTAs.

  10. Design, simulation and comparative analysis of CNT based cascode operational transconductance amplifiers

    Nizamuddin, M.; Loan, Sajad A.; Alamoud, Abdul R.; Abbassi, Shuja A.


    In this work, design and calibrated simulation of carbon nanotube field effect transistor (CNTFET)-based cascode operational transconductance amplifiers (COTA) have been performed. Three structures of CNTFET-based COTAs have been designed using HSPICE and have been compared with the conventional CMOS-based COTAs. The proposed COTAs include one using pure CNTFETs and two others that employ CNTFETs, as well as the conventional MOSFETs. The simulation study has revealed that the CNTFET-based COTAs have significantly outperformed the conventional MOSFET-based COTAs. A significant increase in dc gain, output resistance and slew rate of 81.4%, 25% and 13.2%, respectively, have been achieved in the proposed pure CNT-based COTA in comparison to the conventional CMOS-based COTA. The power consumption in the pure CNT-COTA is 324 times less in comparison to the conventional CMOS-COTA. Further, the phase margin (PM), gain margin (GM), common mode and power supply rejection ratios have been significantly increased in the proposed CNT-based COTAs in comparison to the conventional CMOS-based COTAs. Furthermore, to see the advantage of cascoding, the proposed CNT-based cascode OTAs have been compared with the CNT-based OTAs. It has been observed that by incorporating the concept of cascode in the CNTFET-based OTAs, significant increases in gain (12.5%) and output resistance (13.07%) have been achieved. The performance of the proposed COTAs has been further observed by changing the number of CNTs (N), CNT pitch (S) and CNT diameter (DCNT) in the CNTFETs used. It has been observed that the performance of the proposed COTAs can be significantly improved by using optimum values of N, S and DCNT.

  11. Negative differential transconductance in silicon quantum well metal-oxide-semiconductor field effect/bipolar hybrid transistors

    Introducing explicit quantum transport into Si transistors in a manner amenable to industrial fabrication has proven challenging. Hybrid field-effect/bipolar Si transistors fabricated on an industrial 45 nm process line are shown to demonstrate explicit quantum transport signatures. These transistors incorporate a lateral ion implantation-defined quantum well (QW) whose potential depth is controlled by a gate voltage (VG). Quantum transport in the form of negative differential transconductance (NDTC) is observed to temperatures >200 K. The NDTC is tied to a non-monotonic dependence of bipolar current gain on VG that reduces drain-source current through the QW. These devices establish the feasibility of exploiting quantum transport to transform the performance horizons of Si devices fabricated in an industrially scalable manner

  12. Multifunction Current Differencing Cascaded Transconductance Amplifier (MCDCTA) and Its Application to Current-Mode Multiphase Sinusoidal Oscillator

    Wang, Chunhua; Lin, Hairong


    In this study, a new versatile active element, namely multifunction current differencing cascaded transconductance amplifier (MCDCTA), is proposed. This device which adopts a simple configuration enjoys the performances of low-voltage, low-input and high-output impedance, wide bandwidth etc. It simplifies the design of the current-mode analog signal processing circuit greatly, especially the design of high-order filter and oscillator circuits. Moreover, an example as a new current-mode multiphase sinusoidal oscillator (MSO) using MCDCTA is described in this paper. The proposed oscillator, which employs only one MCDCTA and minimum grounded passive elements, is easy to be realized. It can provide random n (n being odd or even) output current signals and these output currents are equally spaced in phase all at high output impedance terminals. Its oscillation condition and the oscillation frequency can be adjusted independently, linearly and electronically by controlling the bias currents of MCDCTA. The operation of the proposed oscillator has been testified through PSPICE simulation and experimental results.

  13. Impact of gate–source/drain channel architecture on the performance of an operational transconductance amplifier (OTA)

    In this work, we report on the significance of gate–source/drain extension region (also known as underlap design) optimization in double gate (DG) FETs to improve the performance of an operational transconductance amplifier (OTA). It is demonstrated that high values of intrinsic voltage gain (AVOOTA) > 55 dB and unity gain frequency (fTOTA) ∼ 57 GHz in a folded cascode OTA can be achieved with gate-underlap channel design in 60 nm DG MOSFETs. These values correspond to 15 dB improvement in AVOOTA and three fold enhancement in fTOTA over a conventional non-underlap design. OTA performance based on underlap single gate SOI MOSFETs realized in ultra-thin body (UTB) and ultra-thin body BOX (UTBB) technologies is also evaluated. AVOOTA values exhibited by a DG MOSFET-based OTA are 1.3–1.6 times higher as compared to a conventional UTB/UTBB single gate OTA. fTOTA values for DG OTA are 10 GHz higher for UTB OTAs whereas a twofold improvement is observed with respect to UTBB OTAs. The simultaneous improvement in AVOOTA and fTOTA highlights the usefulness of underlap channel architecture in improving gain–bandwidth trade-off in analog circuit design. Underlap channel OTAs demonstrate high degree of tolerance to misalignment/oversize between front and back gates without compromising the performance, thus relaxing crucial process/technology-dependent parameters to achieve 'idealized' DG MOSFETs. Results show that underlap OTAs designed with a spacer-to-straggle (s/σ) ratio of 3.2 and operated below a bias current (IBIAS) of 80 µA demonstrate optimum performance. The present work provides new opportunities for realizing future ultra-wide band OTA design with underlap DG MOSFETs

  14. InP Heterojunction Bipolar Transistor Amplifiers to 255 GHz

    Radisic, Vesna; Sawdai, Donald; Scott, Dennis; Deal, William; Dang, Linh; Li, Danny; Cavus, Abdullah; To, Richard; Lai, Richard


    Two single-stage InP heterojunction bipolar transistor (HBT) amplifiers operate at 184 and 255 GHz, using Northrop Grumman Corporation s InP HBT MMIC (monolithic microwave integrated circuit) technology. At the time of this reporting, these are reported to be the highest HBT amplifiers ever created. The purpose of the amplifier design is to evaluate the technology capability for high-frequency designs and verify the model for future development work.

  15. Study on the ELDRS of bipolar linear operational amplifier

    Bipolar linear devices laboratory irradiation testing results are significantly different from the actual in flight exposure to the radiation. In this paper the total dose irradiation of operational amplifiers, and analysis upon the total dose response of these bipolar circuits under the different test conditions were investigated in the same experiment. Total dose tests of bipolar linear operational amplifiers show susceptible to dose rate, bias and room temperature annealing during exposure. The critical sensitive parameters of operational amplifier are input bias current, input offset current, input offset voltage, and open loop gain, which exhibits both bias and dose rate dependence. With calculating the change of each electrical parameter (Δpara) for each sample at 300 Gy radiation level, it has been found that ratio of the Δpara at low dose rate to the Δpara at high dose rate exceeds 2.46 times for any of the parameters. So these parts are considered to be ELDRS susceptible. After room temperature annealing, the main parameters have time dependence effect at low dose rate and without time dependent effect at high dose rate. (authors)

  16. On-chip frequency compensation with a dual signal path operational transconductance amplifier for a voltage mode control DC/DC converter

    Ye Qiang; Liu Jie; Yuan Bing; Lai Xinquan; Liu Ning


    A novel on-chip frequency compensation circuit for a voltage-mode control DC/DC converter is presented.By employing an RC network in the two signal paths of an operational transconductance amplifier (OTA),the proposed circuit generates two zeros to realize high closed-loop stability.Meanwhile,full on-chip integration is also achieved due to its simple structure.Hence,the number of off-chip components and the board space is greatly reduced.The structure of the dual signal path OTA is also optimized to help get a better transition response.Implemented in a 0.5 μm CMOS process,the voltage mode control DC/DC converter with the proposed frequency compensation circuit exhibits good stability.The test results show that both load and line regulations are less than 0.3%,and the output voltage can be recovered within 15 μs for a 400 mA load step.Moreover,the compensation components area is less than 2% of the die's area and the board space is also reduced by 11%.The efficiency of the whole chip can be up to 95%.

  17. On-chip frequency compensation with a dual signal path operational transconductance amplifier for a voltage mode control DC/DC converter

    A novel on-chip frequency compensation circuit for a voltage-mode control DC/DC converter is presented. By employing an RC network in the two signal paths of an operational transconductance amplifier (OTA), the proposed circuit generates two zeros to realize high closed-loop stability. Meanwhile, full on-chip integration is also achieved due to its simple structure. Hence, the number of off-chip components and the board space is greatly reduced. The structure of the dual signal path OTA is also optimized to help get a better transition response. Implemented in a 0.5 μm CMOS process, the voltage mode control DC/DC converter with the proposed frequency compensation circuit exhibits good stability. The test results show that both load and line regulations are less than 0.3%, and the output voltage can be recovered within 15 μs for a 400 mA load step. Moreover, the compensation components area is less than 2% of the die's area and the board space is also reduced by 11%. The efficiency of the whole chip can be up to 95%. (semiconductor integrated circuits)

  18. Experimental study of transient ionizing radiation effects in bipolar operational amplifier

    The in-situ test system of transient ionizing radiation effects for operational amplifier was established to study the response to transient ionizing irradiation. Three different bipolar operational amplifiers with different bandwidths and slew rates were irradiated using the Qiangguang-Ⅰ accelerator in Northwest Institute of Nuclear Technology. The results show that the response time decreases, as the bandwidth and the slew rate of the bipolar operational amplifiers increase for the same dose rate. Analysis indicates that the slew rate is related to the compensation capacitor for the bipolar operational amplifier with inside compensation capacitor. The smaller the compensation capacitor is, the greater the slew rate is. (authors)

  19. Heterojunction Bipolar Transistor Power Amplifiers for Long-Range X-band Communications Project

    National Aeronautics and Space Administration — In this SBIR Phase I project, Vega Wave Systems, Inc. will develop and demonstrate a novel InGaP-GaAs heterojunction bipolar transistor power amplifier for...

  20. Development of three channel linear bipolar high voltage amplifier (±2 KV) for electrostatic steerer

    Electrostatic steerers and scanners are planned for low energy ion beam facilities at IUAC to steer and scan the ion beam on target. The power supplies for electrostatic steerers are high voltage bipolar DC amplifiers and for scanners are bipolar AC amplifiers. To fulfil the requirements a common unit has been designed and assembled for AC and DC applications. It can be used with electrostatic devices in scanning, steering and sweeping of low energy ion beams at high frequencies to attain uniform implantation. The unit consist of three independent limited bandwidth high voltage, linear bipolar amplifiers (for X-axis, Y-axis and Y1-dog leg plates). The unit has been provided with both local and remote control. (author)

  1. Design of low-voltage bipolar operational amplifiers

    Fonderie, Jeroen

    The design of input stages for low voltage Operational Amplifiers (OpAmps) is considered. The purpose of this design emanates from the objective of having a common mode input voltage range that reaches from one supply rail to the other, and designs that have this feature both at a 2 V and at a 1 V supply are discussed. Possible output stage configurations are analyzed. This discussion is restricted to output stages that have an output voltage range that also reaches from rail to rail. Further, the output stage should be able to supply a sufficiently large output current to the load that is externally connected to the OpAmp. The frequency response of the output stage is the focus of the discussion. The circuit parts that remain to complete the design of the OpAmp are discussed. These circuit parts are the intermediate stage, inserted between the input and output stage to boost the overall gain of the OpAmp, some implementations of the class AB current control circuit, circuitry to protect the output transistor from heavy saturation and from excessive power consumption, and, finally, the proportional to absolute temperature reference current generator. A detailed analysis of the frequency compensation techniques that can be used to stabilize the OpAmp is given. From this theory, design criteria to successfully implement the compensation method are derived. The experimental OpAmp designs and the measurements performed on these designs are described. Conclusions and suggestions for further research are given.

  2. The eight-channel ASIC bipolar transresistance amplifier D0M AMPL-8.3

    Alexeev, G D; Dvornikov, O V; Khokhlov, A I; Mikhailov, V A; Odnokloubov, I A; Tokmenin, V V


    The eight-channel ASIC low-noise bipolar transresistance amplifier D0M Ampl-8.3 has been designed on the basis of BJT-JFET technology for gaseous wire detectors used in high-energy physics experiments. The amplifier has differential gain 130 mV/mu A at 1 k OMEGA, input noise 35 and 60 nA r.m.s. at 0 and 60 pF input capacitance, respectively, leading/trailing edge 7 ns, input resistance approx 50 OMEGA, crosstalks -47 dB, dissipated power 160 triple bond 640 mW/chip for +-3 triple bond 5 V supply. The Ampl-8.3 has been accepted for upgrading the Forward Angle Muon System of the D0 experiment (Fermilab, Batavia, USA), the total number of channels is about 50,000.

  3. Broadband amplifiers for high data rates using InP/InGaAs double heterojunction bipolar transistors

    Schneider, Karl


    This work describes the development process of state-of-the-art electrical broadband amplifiers, which are suitable as modulator drivers in electrical time division multiplex (ETDM) systems, operating at 80 Gbit/s. The realization is successfully accomplished in three major development steps: optimization of the transistor geometry of InP-based Double Heterojunction Bipolar Transistors (DHBT), extraction of large- and small-signal models, and design and realization of lumped and distributed a...

  4. CMOS VHF transconductance-C lowpass filter

    Nauta, B.


    Experimental results of a VHF CMOS transconductance-C lowpass filter are described. The filter is built with transconductors as published earlier. The cutoff frequency can be tuned from 22 to 98 MHz and the measured filter response is very close to the ideal response

  5. A describing function approach to bipolar RF-power amplifier simulation

    Vidkjær, Jens


    A method for fast and accurate computations of the primary performance parameters such as gain, efficiency, output power, and bandwidth in class-C biased RF-power amplifier stages is presented. The method is based on a describing function characterization of the RF-power transistor where the term...

  6. A G-band terahertz monolithic integrated amplifier in 0.5-μm InP double heterojunction bipolar transistor technology

    Ou-Peng, Li; Yong, Zhang; Rui-Min, Xu; Wei, Cheng; Yuan, Wang; Bing, Niu; Hai-Yan, Lu


    Design and characterization of a G-band (140–220 GHz) terahertz monolithic integrated circuit (TMIC) amplifier in eight-stage common-emitter topology are performed based on the 0.5-μm InGaAs/InP double heterojunction bipolar transistor (DHBT). An inverted microstrip line is implemented to avoid a parasitic mode between the ground plane and the InP substrate. The on-wafer measurement results show that peak gains are 20 dB at 140 GHz and more than 15-dB gain at 140–190 GHz respectively. The saturation output powers are ‑2.688 dBm at 210 GHz and ‑2.88 dBm at 220 GHz, respectively. It is the first report on an amplifier operating at the G-band based on 0.5-μm InP DHBT technology. Compared with the hybrid integrated circuit of vacuum electronic devices, the monolithic integrated circuit has the advantage of reliability and consistency. This TMIC demonstrates the feasibility of the 0.5-μm InGaAs/InP DHBT amplifier in G-band frequencies applications. Project supported by the National Natural Science Foundation of China (Grant No. 61501091) and the Fundamental Research Funds for the Central Universities of Ministry of Education of China (Grant Nos. ZYGX2014J003 and ZYGX2013J020).

  7. High Power SiGe X-Band (8~10GHz) Heterojunction Bipolar Transistors and Amplifiers


    Limited by increased parasitics and thermal effects as device size increases, current commercial SiGe power HBTs are difficult to operate at X-band (8~ 12GHz) frequencies with adequate power added efficiencies at high power levels. We find that, by changing the heterostructure and doping profile of SiGe HBTs, their power gain can be significantly improved without resorting to substantial lateral scaling. Furthermore, employing a common-base configuration with a proper doping profile instead of a common-emitter configuration improves the power gain characteristics of SiGe HBTs, thus permitting these devices to be efficiently operated at X-band frequencies. In this paper,we report the results of SiGe power HBTs and MMIC power amplifiers operating at 8~10GHz. At 10GHz,a 22.5dBm (178mW) RF output power with a concurrent gain of 7.32dB is measured at the peak power-added efficiency of 20.0%, and a maximum RF output power of 24.0dBm (250mW) is achieved from a 20 emitter finger SiGe power HBT. The demonstration of a single-stage X-band medium-power linear MMIC power amplifier is also realized at 8GHz. Employing a 10-emitter finger SiGe HBT and on-chip input and output matching passive components, a linear gain of 9.7dB,a maximum output power of 23.4dBm,and peak power added efficiency of 16% are achieved from the power amplifier. The MMIC exhibits very low distortion with 3rd order intermodulation (IM) suppression C/I of -13dBc at an output power of 21.2dBm and over 20dBm 3rd order output intercept point (OIP3).

  8. Transconductance bimodal effect of PDSOI submicron H-gate MOSFETs

    Mei Bo; Bi Jinshun; Bu Jianhui; Han Zhengsheng


    A bimodal effect of transconductance was observed in narrow channel PDSOI sub-micron H-gate PMOSFETs,which was accompanied with the degeneration of device performance.This paper presents a study of the transconductance bimodal effect based on the manufacturing process and electrical properties of those devices.It is shown that this effect is caused by a diffusion of donor impurities from the N+ region of body contact to the P+ poly gate at the neck of the H-gate,which would change the work function differences of the polysilicon gate and substrate.This means that the threshold voltage of the device is different in the width direction,which means that there are parasitic transistors paralleled with the main transistor at the neck of the H-gate.The subsequent devices were fabricated with layout optimization,and it is demonstrated that the bimodal transconductance can be eliminated by mask modification with N+ implantation more than 0.2μm away from a poly gate.

  9. Scanning gate transconductance microscopy and spectroscopy of a mesoscopic ring

    Hackens, Benoit; Martins, Frederico; Faniel, Sebastien; Bayot, Vincent; Pala, Marco; Sellier, Hermann; Huant, Serge; Desplanque, Ludovic; Wallart, Xavier


    In scanning gate microscopy (SGM), a dc voltage is applied to a sharp tip moving in the vicinity of a device. This alters the electrostatic potential seen by electrons inside the device, and consequently changes the device conductance. Here, we superimpose a small ac voltage to the dc bias applied on the tip, and record the change of device conductance at the tip bias modulation frequency, i.e. the local transconductance. We first image the low temperature transconductance of a mesoscopic ring patterned in a two-dimensional electron system (2DES) hosted in an InGaAs/InAlAs heterostructure. The tranconductance images are decorated by concentric features that we associate with charging of electron traps located close to the 2DES. We perform spectroscopy of these traps by positioning the tip close to them, and recording the ring transconductance as a function of the tip dc voltage and the bias accross the quantum ring. We observe Coulomb diamonds in our spectroscopic data, which confirms that Coulomb blockade is at play.

  10. Design of high-linear CMOS circuit using a constant transconductance method for gamma-ray spectroscopy system

    We propose a novel circuit to be applied to the front-end integrated circuits of gamma-ray spectroscopy systems. Our circuit is designed as a type of current conveyor (ICON) employing a constant-gm (transconductance) method which can significantly improve the linearity in the amplified signals by using a large time constant and the time-invariant characteristics of an amplifier. The constant-gm method is obtained by a feedback control which keeps the transconductance of the input transistor constant. To verify the performance of the propose circuit, the time constant variations for the channel resistances are simulated with the TSMC 0.18μm transistor parameters using HSPICE, and then compared with those of a conventional ICON. As a result, the proposed ICON shows only 0.02% output linearity variation and 0.19% time constant variation for the input amplitude up to 100 mV. These are significantly small values compared to a conventional ICON's 1.39% and 19.43%, respectively, for the same conditions.

  11. Ultra-low Voltage CMOS Cascode Amplifier

    Lehmann, Torsten; Cassia, Marco

    In this paper, we design a folded cascode operational transconductance amplifier in a standard CMOS process, which has a measured 69 dB DC gain, a 2 MHz bandwidth and compatible input- and output voltage levels at a 1 V power supply. This is done by a novel Current Driven Bulk (CDB) technique...

  12. Bipolar Disorder

    Bipolar disorder is a serious mental illness. People who have it go through unusual mood changes. They go ... The down feeling is depression. The causes of bipolar disorder aren't always clear. It runs in families. ...

  13. Bipolar Disorder

    Bipolar disorder is a serious mental illness. People who have it go through unusual mood changes. They ... The down feeling is depression. The causes of bipolar disorder aren't always clear. It runs in ...

  14. Bipolar Disorder

    ... types of psychotherapies. Other Treatment Options Electroconvulsive Therapy (ECT) : ECT can provide relief for people with severe bipolar ... been able to recover with other treatments. Sometimes ECT is used for bipolar symptoms when other medical ...

  15. Bipolar semicopulas

    Greco, S.; Mesiar, Radko; Rindone, F.

    Linz: Univesitatsdirektion, JKU Linz, Austria, 2013. s. 63-65. [Linz Seminar on Fuzzy Set Theory /34./. 26.02.2013-02.03.2013, Linz] R&D Projects: GA ČR GAP402/11/0378 Keywords : bipolar integral * bipolar semicopula * bipolar aggregation Subject RIV: BA - General Mathematics

  16. Bipolar Disorder.

    Spearing, Melissa

    Bipolar disorder, a brain disorder that causes unusual shifts in a person's mood, affects approximately one percent of the population. It commonly occurs in late adolescence and is often unrecognized. The diagnosis of bipolar disorder is made on the basis of symptoms, course of illness, and when possible, family history. Thoughts of suicide are…

  17. Bipolar disorder.

    Grande, Iria; Berk, Michael; Birmaher, Boris; Vieta, Eduard


    Bipolar disorder is a recurrent chronic disorder characterised by fluctuations in mood state and energy. It affects more than 1% of the world's population irrespective of nationality, ethnic origin, or socioeconomic status. Bipolar disorder is one of the main causes of disability among young people, leading to cognitive and functional impairment and raised mortality, particularly death by suicide. A high prevalence of psychiatric and medical comorbidities is typical in affected individuals. Accurate diagnosis of bipolar disorder is difficult in clinical practice because onset is most commonly a depressive episode and looks similar to unipolar depression. Moreover, there are currently no valid biomarkers for the disorder. Therefore, the role of clinical assessment remains key. Detection of hypomanic periods and longitudinal assessment are crucial to differentiate bipolar disorder from other conditions. Current knowledge of the evolving pharmacological and psychological strategies in bipolar disorder is of utmost importance. PMID:26388529

  18. Transconductance fluctuations as a probe for interaction induced quantum Hall states in graphene

    Lee, Dong Su; Skakalova, Viera; Weitz, R. Thomas; von Klitzing, Klaus; Smet, Jurgen H.


    Transport measurements normally provide a macroscopic, averaged view of the sample, so that disorder prevents the observation of fragile interaction induced states. Here, we demonstrate that transconductance fluctuations in a graphene field effect transistor reflect charge localization phenomena on the nanometer scale due to the formation of a dot network which forms near incompressible quantum states. These fluctuations give access to fragile broken-symmetry and fractional quantum Hall state...

  19. Concurrent Detection and Classification of Faults in Matrix Converter using Trans-Conductance

    Sarah Azimi; Mehdi Vejdaniamiri


    This paper presents a fault diagnostic algorithm for detecting and locating open-circuit and short-circiut faults in switching components of matrix converters (MCs) which can be effectively used to drive a permanent magnet synchronous motor for research in critical applications. The proposed method is based on monitoring the voltages and currents of the switches. These measurements are used to evaluate the forward trans-conductance of each transistor for different values of switch voltages. T...

  20. Bipolar Disorder

    ... lows). These aren't the normal periods of happiness and sadness that everyone experiences from time to ... with long-lasting medical conditions (such as asthma , diabetes , or epilepsy ), teens with bipolar disorder need to ...

  1. Bipolar disorder

    Goodwin, Frederick K; Ghaemi, S Nassir


    Bipolar disorder's unique combination of three characteristics - clear genetic diathesis, distinctive clinical features, early availability of an effective treatment (lithium) - explains its special place in the history of psychiatry and its contribution to the current explosive growth of neuroscience. This article looks at the state of the art in bipolar disorder from the vantage point of: (i) genetics (possible linkages on chromosomes 18 and 21q, polygenic hypothesis, research into genetic ...

  2. LC sine-wave oscillators using general-purpose voltage operational-amplifiers

    Jakas, M M


    It has been found that some text-books show LC-oscillators that may not work as assumed. Thus, the typical example showing a LC-oscillator driven by a voltage operational-amplifier is simply wrong. The difficulty stems from the fact that such oscillators are normally built to work with transconductance- not with voltage-amplifiers. Such a difficulty however, can be readily solved by connecting a resistor in series with the so-called frequency-determining network.

  3. Molecular Layer-seeded Ultra-thin Top-gate Dielectrics for High Transconductance Graphene Transistors

    Sangwan, Vinod; Jariwala, Deep; Karmel, Hunter; Alaboson, Justice; Lauhon, Lincoln; Marks, Tobin; Hersam, Mark


    The potential of graphene in integrated analog and digital circuits can only be fully realized through incorporation of ultra-thin gate dielectrics to enable large-scale small-channel graphene field-effect transistors (GFETs). Atomic-layer deposition (ALD) is a viable technique to fabricate gate-dielectrics, however, it requires a seeding layer on otherwise inert graphene. Here, we demonstrate a single molecule thick perylene-3,4,9,10-tetracarboxylic dianhydride overlayer as an effective seeding layer to grow high-κ Al2O3 on mechanically exfoliated graphene for high-performance GFETs. Using an ultra-thin (films (5-10 nm), we demonstrate fabrication of the thinnest ALD-grown gate-dielectric (4 nm) reported to date in top-gated GFETs. This yields high performance GFETs with the intrinsic transconductance parameter approaching 2.4 mS and the field-effect mobility ˜3000 cm^2/Vs. We also demonstrate generalization of this molecular layer seeded-ALD growth method to higher- κ gate dielectrics, yielding further enhanced GFET transconductance for possible application to radio-frequency circuits.

  4. Improve the transconductance of a graphene field-effect transistor by folding graphene into a wedge

    Cao, Guiming; Liu, Weihua; Cao, Meng; Li, Xin; Zhang, Anping; Wang, Xiaoli; Chen, Bangdao


    The transport property of a graphene wedge channel is studied theoretically and its leakage current through field emission is estimated when considering the effect of the internal electric field. The transconductance of the graphene transistor is improved from 0.016 to 0.321 μS μm‑1 when the graphene is folded into a wedge (with angle of wedge π/6 and radius curvature 2.7 nm at the tip), while the wedge height is much smaller than the space between the top-gate and the channel. The improved transconductance is due to the locally enhanced electric field, which results in a potential well and causes electron accumulation at the wedge tip. The leakage current through field emission J FE shows a super-linear increase with the channel conductive current J DS, where overall the electron supply for the field emission at the wedge tip is improved by the channel bias voltage V DS.

  5. Concurrent Detection and Classification of Faults in Matrix Converter using Trans-Conductance

    Sarah Azimi


    Full Text Available This paper presents a fault diagnostic algorithm for detecting and locating open-circuit and short-circiut faults in switching components of matrix converters (MCs which can be effectively used to drive a permanent magnet synchronous motor for research in critical applications. The proposed method is based on monitoring the voltages and currents of the switches. These measurements are used to evaluate the forward trans-conductance of each transistor for different values of switch voltages. These trans-conductance values are then compared to the nominal values. Under healthy conditions, the values obtained for the fault signal is less than the tolerable value. Under the open/short-circuit conditions, the fault signal exceeds the threshold, hence enables the matrix converter drive to detect and exactly identify the location of the faulty IGBT. The main advantages of this diagnostic method include fast detection and locating of the faulty IGBT, easiness of implementation and independency of the modulation strategy of the converter.

  6. Distributed-Channel Bipolar Device: Experimentation, Analytical Modeling and Applications.

    Jiang, Fenglai

    Experimental results and theoretical modeling for four terminal distributed channel bipolar devices (DCBD) are presented. The DCBD device is comprised of an interwoven BJT and MOSFET. The device may be characterized as a MOSFET with a bipolar transistor source distributed under the MOSFET channel. Alternatively, the device may be represented as a BJT where a MOSFET channel provides the current collection function. The physical layout of the device is that of a n-channel MOSFET placed above a p-Si epitaxial base region which was grown on an n^+-Si substrate emitter. Distributed electronic behavior exhibits itself through self-biasing influences of the channel-collected current on the channel-base junction bias. For appropriate biasing, the MOSFET channel divides itself into two regions exhibiting forward active and saturation BJT behavior. Both experimental results and theoretical modeling are provided. Experimental results for "large area" rectangular gate, circular gate and trapezoidal gate DCBD are reported. The experimental results exhibit the transconductance threshold voltage, beta fall off and transconductance fall-off features reported previously by others. A "large area" trapezoidal gate structure is incorporated to illustrate the gate area influences on the electrical characteristics and to provide a model sensitive structure for evaluating the validity of the theory developed in the dissertation. An analytical model based on conventional MOSFET and bipolar theories is developed. The analytical model is applied to the large gate area devices (example: 0.127 mm rectangular gate length) and smaller dimensional gate devices down to 0.9 micron rectangular gate length. The theoretical results show good agreement with the large gate area experimental results. Application examples are provided. The use of the base current invariant transconductance threshold voltage as a reference voltage is discussed. Comparison of the transconductance threshold voltage

  7. On Bipolar Soft Sets

    Shabir, Muhammad; Naz, Munazza


    We have studied the concept of bipolarity of information in the soft sets. We have defined bipolar soft sets and basic operations of union, intersection and complementation for bipolar soft sets. Examples of bipolar soft sets and an application of bipolar soft sets in a decision making problem with general algorithms have also been presented at the end.

  8. Cayley Bipolar Fuzzy Graphs

    Alshehri, Noura O.; Muhammad Akram


    We introduce the concept of Cayley bipolar fuzzy graphs and investigate some of their properties. We present some interesting properties of bipolar fuzzy graphs in terms of algebraic structures. We also discuss connectedness in Cayley bipolar fuzzy graphs.

  9. Transtorno bipolar

    Alda Martin


    Full Text Available Os resultados de estudos de famílias sugerem que o transtorno bipolar tenha uma base genética. Essa hipótese foi reforçada em estudos de adoção e de gêmeos. A herança do transtorno bipolar é complexa, envolve vários genes, além de apresentar heterogeneidade e interação entre fatores genéticos e não-genéticos. Achados, que já foram replicados, já implicaram os cromossomos 4, 12, 18 e 21, entre outros, na busca por genes de suscetibilidade. Os resultados mais promissores foram obtidos através de estudos de ligação. Por outro lado, os estudos de associação geraram dados interessantes, mas ainda vagos. Os estudos de populações de pacientes homogêneos e a melhor definição do fenótipo deverão contribuir para avanços futuros. A identificação dos genes relacionados ao transtorno bipolar irá permitir o melhor entendimento e tratamento dessa doença.

  10. Operational amplifiers

    Dostal, Jiri


    This book provides the reader with the practical knowledge necessary to select and use operational amplifier devices. It presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits.Provides the reader with practical knowledge necessary to select and use operational amplifier devices. Presents an extensive treatment of applications and a practically oriented, unified theory of operational circuits

  11. Neutrality in bipolar structures

    Montero, Javier; Rodríguez, J. Tinguaro; Franco, Camilo;


    In this paper, we want to stress that bipolar knowledge representation naturally allows a family of middle states which define as a consequence different kinds of bipolar structures. These bipolar structures are deeply related to the three types of bipolarity introduced by Dubois and Prade, but o...

  12. Discrete bipolar universal integrals

    Greco, Salvatore; Mesiar, Radko; Rindone, Fabio


    The concept of universal integral, recently proposed, generalizes the Choquet, Shilkret and Sugeno integrals. Those integrals admit a discrete bipolar formulation, useful in those situations where the underlying scale is bipolar. In this paper we propose the concept of discrete bipolar universal integral, in order to provide a common framework for bipolar discrete integrals, including as special cases the discrete Choquet, Shilkret and Sugeno bipolar integrals. Moreover we provide two differe...

  13. Analysis and implementation of an improved recycling folded cascode amplifier

    李一雷; 韩科峰; 闫娜; 谈熙; 闵昊


    A generally improved recycling folded cascode (IRFC) is analyzed and implemented.Analysis and comparisons among the IRFC,the original recycling folded cascode (RFC) and the conventional folded cascode (FC) are made,and it is shown that with the flexible structure of IRFC,significant enhancement in transconductance,slew rate and noise can be achieved.Prototype amplifiers were fabricated in 0.13 μm technology.Measurement shows that IRFC has 3 × enhancement in gain-bandwidth and slew rate over conventional FC,and the enhancement is 1.5× when compared with the RFC.

  14. Generalized bipolar product and sum

    Greco, Salvatore; Mesiar, Radko; Rindone, Fabio


    Aggregation functions on [0, 1] with annihilator 0 can be seen as a generalized product on [0, 1]. We study the generalized product on the bipolar scale [−1, 1], stressing the axiomatic point of view ( compare also [9]). Based on newly introduced bipolar properties, such as the bipolar increasingness, bipolar unit element, bipolar idempotent element, several kinds of generalized bipolar product are introduced and studied. A special stress is put on bipolar semicopulas, bipolar quasi-copulas a...

  15. Integration of GaInP/GaAs heterojunction bipolar transistors and high electron mobility transistors

    Yang, YF; Hsu, CC; Yang, ES


    Integration of carbon-doped GaInP/GaAs heterojunction bipolar transistors (HBT's) and high electron mobility transistors (HEMT's) is demonstrated by growing an HBT on the top of a HEMT. A current gain of 60. a cutoff frequency of 59 GHz and a maximum oscillation frequency of 68 GHz were obtained for a 5 × 15 μm 2 self-aligned HBT. The HEMT with a gate length of 1.5 μm has a transconductance of 210 mS/mm, a cutoff frequency of 9 GHz and a maximum oscillation frequency of 22 GHz. It is shown th...

  16. Help With Bipolar Disorders

    ... a Psychiatrist Patients & Families All Topics Help With Bipolar Disorders Curated and updated for the community by APA Topic Information Bipolar disorders are brain disorders that cause changes in a ...

  17. Staging Bipolar Disorder.

    Vieta i Pascual, Eduard, 1963-; Reinares, M.; Rosa, A. R.


    The purpose of this study was to analyze the evidence supporting a staging model for bipolar disorder. The authors conducted an extensive Medline and Pubmed search of the published literature using a variety of search terms (staging, bipolar disorder, early intervention) to find relevant articles, which were reviewed in detail. Only recently specific proposals have been made to apply clinical staging to bipolar disorder. The staging model in bipolar disorder suggests a progression from prodro...

  18. Cytokines in bipolar disorder

    Munkholm, Klaus; Vinberg, Maj; Vedel Kessing, Lars


    BACKGROUND: Current research and hypothesis regarding the pathophysiology of bipolar disorder suggests the involvement of immune system dysfunction that is possibly related to disease activity. Our objective was to systematically review evidence of cytokine alterations in bipolar disorder according...... to affective state. METHODS: We conducted a systemtic review of studies measuring endogenous cytokine concentrations in patients with bipolar disorder and a meta-analysis, reporting results according to the PRISMA statement. RESULTS: Thirteen studies were included, comprising 556 bipolar disorder...

  19. Management of Bipolar Depression

    Jae Seung Chang; Kyooseob Ha


    Patients with bipolar disorder spend more time in a depressed than manic state, even with individualized treatment. To date, bipolar depression is often misdiagnosed and ineffectively managed both for acute episodes and residual symptoms. This review attempts to summarize the current status of available treatment strategies in the treatment of bipolar depression. For acute and prophylactic treatment, a substantial body of evidence supports the antidepressive efficacy of lithium for bipolar di...

  20. Bipolar Fuzzy Integrals

    Greco, Salvatore; Rindone, Fabio


    In decision analysis and especially in multiple criteria decision analysis, several non additive integrals have been introduced in the last sixty years. Among them, we remember the Choquet integral, the Shilkret integral and the Sugeno integral. Recently, the bipolar Choquet integral has been proposed for the case in which the underlying scale is bipolar. In this paper we propose the bipolar Shilkret integral and the bipolar Sugeno integral. Moreover, we provide an axiomatic characterization ...

  1. Continuous-Time ΣΔ ADC with Implicit Variable Gain Amplifier for CMOS Image Sensor

    Fang Tang; Amine Bermak; Amira Abbes; Mohieddine Amor Benammar


    This paper presents a column-parallel continuous-time sigma delta (CTSD) ADC for mega-pixel resolution CMOS image sensor (CIS). The sigma delta modulator is implemented with a 2nd order resistor/capacitor-based loop filter. The first integrator uses a conventional operational transconductance amplifier (OTA), for the concern of a high power noise rejection. The second integrator is realized with a single-ended inverter-based amplifier, instead of a standard OTA. As a result, the power consump...

  2. Irregular Bipolar Fuzzy Graphs

    Samanta, Sovan; Pal, Madhumangal


    In this paper, we define irregular bipolar fuzzy graphs and its various classifications. Size of regular bipolar fuzzy graphs is derived. The relation between highly and neighbourly irregular bipolar fuzzy graphs are established. Some basic theorems related to the stated graphs have also been presented.

  3. A low power and low distortion rail-to-rail input/output amplifier using constant current technique

    A rail-to-rail amplifier with constant transconductance, intended for audio processing, is presented. The constant transconductance is obtained by a constant current technique based on the input differential pairs operating in the weak inversion region. MOSFETs working in the weak inversion region have the advantages of low power and low distortion. The proposed rail-to-rail amplifier, fabricated in a standard 0.35 μm CMOS process, occupies a core die area of 75 x 183 μm2. Measured results show that the maximum power consumption is 85.37 μW with a supply voltage of 3.3 V and the total harmonic distortion level is 1.2% at 2 kHz. (semiconductor integrated circuits)

  4. A low power and low distortion rail-to-rail input/output amplifier using constant current technique

    Yan, Liu; Yiqiang, Zhao; Shilin, Zhang; Hongliang, Zhao


    A rail-to-rail amplifier with constant transconductance, intended for audio processing, is presented. The constant transconductance is obtained by a constant current technique based on the input differential pairs operating in the weak inversion region. MOSFETs working in the weak inversion region have the advantages of low power and low distortion. The proposed rail-to-rail amplifier, fabricated in a standard 0.35 μm CMOS process, occupies a core die area of 75 × 183 μm2. Measured results show that the maximum power consumption is 85.37 μW with a supply voltage of 3.3 V and the total harmonic distortion level is 1.2% at 2 kHz.

  5. Mood stability versus mood instability in bipolar disorder: A possible role for emotional mental imagery

    Holmes, Emily A.; Deeprose, Catherine; Fairburn, Christopher G.; Wallace-Hadrill, Sophie M.A.; Bonsall, Michael B.; Geddes, John R.; Goodwin, Guy M.


    A cognitive model of bipolar disorder suggests that mental imagery acts as an emotional amplifier of mood and may be heightened in bipolar disorder. First, we tested whether patients with bipolar disorder would score higher on mental imagery measures than a matched healthy control group. Second, we examined differences in imagery between patients divided into groups according to their level of mood stability. Mood ratings over approximately 6-months, made using a mobile phone messaging system...

  6. Costs of Bipolar Disorder

    Leah S. Kleinman; Ana Lowin; Emuella Flood; Gian Gandhi; Eric Edgell; Revicki, Dennis A


    Bipolar disorder is a chronic affective disorder that causes significant economic burden to patients, families and society. It has a lifetime prevalence of approximately 1.3%. Bipolar disorder is characterised by recurrent mania or hypomania and depressive episodes that cause impairments in functioning and health-related quality of life. Patients require acute and maintenance therapy delivered via inpatient and outpatient treatment. Patients with bipolar disorder often have contact with the s...

  7. Treatment Resistant Bipolar Disorder

    Elvan Ozalp; Ersin Hatice Karslioglu


    Many patients diagnosed with bipolar disorder respond incompletely or unsatisfactorily to available treatments. Defining refractoriness in bipolar disorder is a complex issue and should concern and include either every phase and pole or the disorder as a whole. There are only limited and sometimes confusing data on the treatment of refractory bipolar patients. The objective of this paper was to review the evidence for treatment options in treatment resistant patients on depressive, manic atta...

  8. Bipolar Affective Disorder and Migraine

    Birk Engmann


    This paper consists of a case history and an overview of the relationship, aetiology, and treatment of comorbid bipolar disorder migraine patients. A MEDLINE literature search was used. Terms for the search were bipolar disorder bipolar depression, mania, migraine, mood stabilizer. Bipolar disorder and migraine cooccur at a relatively high rate. Bipolar II patients seem to have a higher risk of comorbid migraine than bipolar I patients have. The literature on the common roots of migraine and ...

  9. A Modified Bipolar Translinear Cell with Improved Linear Range and Its Applications

    N. Merz


    Full Text Available This paper presents a technique to extend the linear input voltage range of a sinh mixed translinear cell proposed by Fabre [1]. This technique extends the linear operation range of the circuit by inserting common-anode-connected pairs into the mixed translinear cell. Then the relationship between the output current and the input voltage is developed to be linear. The transconductance gain can be adjusted electronically while keeping its linearity. The performance of the proposed circuit is verified by mathematical analysis and by SPICE simulations. Finally, applications of the proposed cell in a floating resistor and a CCCII for designing an instrumentation amplifier are presented.

  10. Measurement of microdosimetric spectra using an amplifier with logarithmic response

    A 3-1/2 decade logarithmic pulse amplifier was developed for use in microdosimetry. A block diagram of the instrument is given. The input shaping amplifier is designed to accept output pulses from a charge sensitive preamplifier with a maximum full scale amplitude of 8 volts. Output of the shaping amplifier is a bipolar, positive lobe leading RC shaped pulse with a maximum linear range approximately 200 millivolts. Following the logarithmic converter is a voltage amplifier which is used to increase the signal level before it is applied through the linear gate to the output buffer-amplifier. The signal at the output connector is a positive pulse compatible with most conventional pulse height analyzers. The gain of the linear amplifier is adjustable over 10 to 1 range by means of front panel controls

  11. Interpretation of transconductance dispersion in AlGaAs/InGaAs pseudomorphic high electron mobility transistor by capacitance deep level transient spectroscopy

    Choi, K J; Yoo, H M; Lee, G Y


    The transconductance dispersion in AlGaAs/InGaAs PHEMT grown by MBE was interpreted by means of capacitance DLTS technique. When the gate bias was -0.2 V, the transconductance decreased at a very broad frequency range of 5.5 Hz -1.7x10 sup 4 Hz. However, when a positive bias was applied to the gate, the transconductance increased at a low frequency range and then decreased at a high frequency range. In the transconductance dispersion measurement as a function of temperature, the transition frequency shifted to higher frequency region with the increase in temperature. The emission energy for the change in the transition frequency was determined to be 0.394 eV from the temperature dependency of the transition frequency. In the capacitance DLTS measurements, we observed DX-center with thermal activation energy of 0.420 eV and two hole trap-like signals. The DX-center peak decreased as the filling pulse decreased from +0.6 V and disappeared at the bias of -0.1 V. Comparing the activation energy of DX-center in DL...

  12. Low cost instrumentation amplifier

    Sturman, J. C.


    Amplifier can be used for many applications requiring high input impedance and common mode rejection, low drift, and gain accuracy on order of one percent. Performance of inexpensive amplifier approaches that of some commercial instrumentation amplifiers in many specifications.

  13. Properties of Bipolar Fuzzy Hypergraphs

    Akram, M.; Dudek, W. A.; Sarwar, S.


    In this article, we apply the concept of bipolar fuzzy sets to hypergraphs and investigate some properties of bipolar fuzzy hypergraphs. We introduce the notion of $A-$ tempered bipolar fuzzy hypergraphs and present some of their properties. We also present application examples of bipolar fuzzy hypergraphs.

  14. Neuroinflammation in bipolar disorders

    Georgios D Kotzalidis


    Full Text Available Recent literature based on peripheral immunity findings speculated that neuroinflammation, with its connection to microglial activation, is linked to bipolar disorder. The endorsement of the neuroinflammatory hypotheses of bipolar disorder requires the demonstration of causality, which requires longitudinal studies. We aimed to review the evidence for neuroinflammation as a pathogenic mechanism of the bipolar disorder. We carried out a hyper inclusive PubMed search using all appropriate neuroinflammation-related terms and crossed them with bipolar disorder-related terms. The search produced 310 articles and the number rose to 350 after adding articles from other search engines and reference lists. Twenty papers were included that appropriately tackled the issue of the presence (but not of its pathophysiological role of neuroinflammation in bipolar disorder. Of these, 15 were postmortem and 5 were carried out in living humans. Most articles were consistent with the presence of neuroinflammation in bipolar disorder, but factors such as treatment may mask it. All studies were cross-sectional, preventing causality to be inferred. Thus, no inference can be currently made about the role of neuroinflammation in bipolar disorder, but a link is likely. The issue remains little investigated, despite an excess of reviews on this topic.

  15. Types of Bipolar Disorder

    ... improve the lives of people who have mood disorders. The Power of Peers DBSA envisions wellness for people who live with depression and bipolar disorder. Because DBSA was created for and is led ...

  16. Bipolar membrane characterization

    Richau, K.; Kůdela, Vlastimil

    Enschede : Twente University Press, 2001 - (Kemperman, A.), s. 112-147 ISBN 903651523 R&D Projects: GA MŠk ME 079 Keywords : bipolar membranes * water dissociation * methods for characterisation Subject RIV: CD - Macromolecular Chemistry

  17. Gain ranging amplifier

    A gain ranging amplifier system is provided for use in the acquisition of data. Voltage offset compensation is utilized to correct errors in the gain ranging amplifier system caused by thermal drift and temperature dependent voltage offsets, both of which are associated with amplifiers in the gain ranging amplifier system

  18. Thickness-dependent carrier transport and optically enhanced transconductance gain in III-VI multilayer InSe

    Ho, Ching-Hwa


    Multilayer InSe with a thickness above ∼20 nm, is a direct semiconductor with a peak absorption wavelength approaching λ = 1000 nm, which is a promising candidate for solar-energy conversion and 2D optoelectronics devices. We present herein the experimental observations of thickness-dependent conductivity and photoconductive-responsivity spectrum in multilayer InSe as well as optically enhanced transconductance gain in the multilayer InSe metal-semiconductor-field-effect transistor (MESFET) illuminated by a halogen lamp. The voltage-current (V-I) measurement result shows multilayer InSe belongs to a p-type semiconductor, which can form a p-channel FET device. Thickness (t) dependent conductivity (σ) of multilayer InSe reveals about six-order variation from 5076 (Ω-cm)‑1 (t = 5 nm) to 2.56 × 10‑3 (Ω-cm)‑1 (t = 184 μm, bulk) following a relationship of σ ∝ t ‑1.38. The highest conductivity in a thin InSe (e.g. t = 5 nm) is due to the increase of carrier density when the thickness is decreased. The photoresponsivity spectrum of a Ag-InSe-Ag multilayer photoconductor demonstrates a prominent peak absorption at 1.1 ∼ 1.3 eV, matches well with the direct-free-exciton energy of the InSe. A multilayer p-InSe MESFET was tested by V-I measurement. The transconductance was measured and determined to be {g}m={≤ft|\\tfrac{\\partial {{{I}}}{{D}}}{\\partial {{{V}}}{{G}}}\\right|}{{{V}}{{SD}}={{2V}}} = ({1.25 +/- 0.008})× {10}-4≤ft(\\tfrac{{{A}}}{{{V}}}\\right). The gm value will enhance about three times when the MESFET was placed under the illumination of a tungsten halogen lamp of a lower power density ∼0.5 mW · cm‑2. All the experimental results demonstrate multilayer InSe a promising 2D material available for microelectronics and optoelectronics applications.

  19. Amplified Quantum Transforms

    Cornwell, David


    In this thesis we investigate two new Amplified Quantum Transforms. In particular we create and analyze the Amplified Quantum Fourier Transform (Amplified-QFT) and the Amplified-Haar Wavelet Transform. First, we provide a brief history of quantum mechanics and quantum computing. Second, we examine the Amplified-QFT in detail and compare it against the Quantum Fourier Transform (QFT) and Quantum Hidden Subgroup (QHS) algorithms for solving the Local Period Problem. We calculate the probabiliti...

  20. Bipolar Affective Disorder and Migraine

    Birk Engmann


    Full Text Available This paper consists of a case history and an overview of the relationship, aetiology, and treatment of comorbid bipolar disorder migraine patients. A MEDLINE literature search was used. Terms for the search were bipolar disorder bipolar depression, mania, migraine, mood stabilizer. Bipolar disorder and migraine cooccur at a relatively high rate. Bipolar II patients seem to have a higher risk of comorbid migraine than bipolar I patients have. The literature on the common roots of migraine and bipolar disorder, including both genetic and neuropathological approaches, is broadly discussed. Moreover, bipolar disorder and migraine are often combined with a variety of other affective disorders, and, furthermore, behavioural factors also play a role in the origin and course of the diseases. Approach to treatment options is also difficult. Several papers point out possible remedies, for example, valproate, topiramate, which acts on both diseases, but no first-choice treatments have been agreed upon yet.

  1. Lightweight bipolar storage battery

    Rowlette, John J. (Inventor)


    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.

  2. Significance of the double-layer capacitor effect in polar rubbery dielectrics and exceptionally stable low-voltage high transconductance organic transistors

    Wang, Chao; Lee, Wen-Ya; Kong, Desheng; Pfattner, Raphael; Schweicher, Guillaume; Nakajima, Reina; Lu, Chien; Mei, Jianguo; Lee, Tae Hoon; Wu, Hung-Chin; Lopez, Jeffery; Diao, Ying; Gu, Xiaodan; Himmelberger, Scott; Niu, Weijun; Matthews, James R.; He, Mingqian; Salleo, Alberto; Nishi, Yoshio; Bao, Zhenan


    Both high gain and transconductance at low operating voltages are essential for practical applications of organic field-effect transistors (OFETs). Here, we describe the significance of the double-layer capacitance effect in polar rubbery dielectrics, even when present in a very low ion concentration and conductivity. We observed that this effect can greatly enhance the OFET transconductance when driven at low voltages. Specifically, when the polar elastomer poly(vinylidene fluoride-co-hexafluoropropylene) (e-PVDF-HFP) was used as the dielectric layer, despite a thickness of several micrometers, we obtained a transconductance per channel width 30 times higher than that measured for the same organic semiconductors fabricated on a semicrystalline PVDF-HFP with a similar thickness. After a series of detailed experimental investigations, we attribute the above observation to the double-layer capacitance effect, even though the ionic conductivity is as low as 10-10 S/cm. Different from previously reported OFETs with double-layer capacitance effects, our devices showed unprecedented high bias-stress stability in air and even in water.

  3. Portable musical instrument amplifier

    Christian, David E. (Danbury, CT)


    The present invention relates to a musical instrument amplifier which is particularly useful for electric guitars. The amplifier has a rigid body for housing both the electronic system for amplifying and processing signals from the guitar and the system's power supply. An input plug connected to and projecting from the body is electrically coupled to the signal amplifying and processing system. When the plug is inserted into an output jack for an electric guitar, the body is rigidly carried by the guitar, and the guitar is operatively connected to the electrical amplifying and signal processing system without use of a loose interconnection cable. The amplifier is provided with an output jack, into which headphones are plugged to receive amplified signals from the guitar. By eliminating the conventional interconnection cable, the amplifier of the present invention can be used by musicians with increased flexibility and greater freedom of movement.

  4. Amplifier for nuclear spectrometry

    The spectroscopy amplifier model AE-020 is designed to adjust suitable the pulses coming from nuclear radiation detectors. Due to is capacity and specifications, the amplifier can be used together with high and medium resolution spectroscopy system

  5. Bipolar battery construction

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


    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.

  6. The bipolar universal integral

    Greco, S.; Mesiar, Radko; Rindone, F.

    Heidelberg: Springer, 2012 - (Greco, S.; Bouchon-Meunier, B.; Coletti, G.; Fedrizzi, M.; Matarazzo, B.; Yager, R.), s. 360-369. (Communications in Computer and Information Science. 299). ISBN 978-3-642-31717-0. ISSN 1865-0929. [IPMU 2012 /14./. Catania (IT), 09.07.2012-13.07.2012] R&D Projects: GA ČR GAP402/11/0378 Institutional support: RVO:67985556 Keywords : bipolar integral * Choquet integral * universal integral Subject RIV: BA - General Mathematics

  7. High voltage distributed amplifier

    Willems, D.; Bahl, I.; Wirsing, K.


    A high-voltage distributed amplifier implemented in GaAs MMIC technology has demonstrated good circuit performance over at least two octave bandwidth. This technique allows for very broadband amplifier operation with good efficiency in satellite, active-aperture radar, and battery-powered systems. Also, by increasing the number of FETs, the amplifier can be designed to match different voltage rails. The circuit does require a small amount of additional chip size over conventional distributed amplifiers but does not require power dividers or additional matching networks. This circuit configuration should find great use in broadband power amplifier design.

  8. Bipolar Disorder in Turkey

    Bulent Kadri Gultekin


    Full Text Available Assessment of studies related with bipolar disorder in Turkey did not reveal an epidemiologically qualified field study. Most of the studies are hospital based or clinical studies which did not include a systematical scanning and did not aim to collect any epidemiological data and transfer information to health authorities. The generalizability of these studies to our community is far from being valid and reliable. On the other hand, a profile which will be created by reviewing the findings of these studies performed in various regions of Turkey will have a contribution to knowing the and ldquo;unique to us and rdquo; features of bipolar disorder and determining cultural risk factors. All this information can constitute a basis for formation and development of public mental health services related with bipolar disorder. In Turkey, the need for epidemiologically significant, polycentric, public sampled studies with broad participation is indispensable. Although our psychiatric epidemiology and clinical studies include necessary scientific basis, they are not powerful enough to evaluate the authentic and progressional relations such as rapid urbanization and immigration. The aim of this review is to evaluate and discuss prominent epidemiological findings, deficiencies and possibile future activities related with studies conducted in Turkey about bipolar disorder.. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(2.000: 199-209

  9. Bipolar bozukluklarda intihar

    SAYIL, Işık


    Makalede bipolar bozukluklarda intihar olgusuuygulamadan gelen deneyimler doğrultusundagözden geçirilmiştir. İntihar girişimlerinde ilk yardımtartışılmış ve acil serviste kriz ekibinin çalışmasıanlatılmıştır.

  10. Discrete bipolar universal integrals

    Greco, S.; Mesiar, Radko; Rindone, F.


    Roč. 252, č. 1 (2014), s. 55-65. ISSN 0165-0114 R&D Projects: GA ČR GAP402/11/0378 Institutional support: RVO:67985556 Keywords : bipolar integral * universal integral * Choquet integral Subject RIV: BA - General Mathematics Impact factor: 1.986, year: 2014




    YinYang bipolar sets, bipolar lattice, bipolar L-crisp sets, and Bipolar L-fuzzy sets are presented for bipolar information/knowledge fusion, visualization, and decision. First, a bipolar lattice B is defined as a 4-tuple (B, ⊕, &, ⊗) in which every pair of elements has a bipolar lub (blub ⊕), a bipolar glb (bglb &), and a cross-pole glb (cglb ⊗). A bipolar L-set (crisp or fuzzy) B = (B-, B+) in X to a bipolar lattice BL is defined as a bipolar equilibrium function or mapping B : X ⇒ BL. A st...

  12. Current Controlled Current Differencing Buffered Amplifier: Implementation and Applications

    Sudhanshu Maheshwari


    Full Text Available A new four terminal current-controlled active element is introduced, where parasitic resistances at two current input ports are controlled leading to the definition of current-controlled current differencing buffered amplifier. Bipolar implementation and as application current-mode band-pass filter circuits are proposed. Simulation results using real device parameters are included, which show device bandwidth of 35 MHz, low total harmonic distortions, and tuning over a wide current range.

  13. `Soft' amplifier circuits based on field-effect ionic transistors

    Boon, Niels; Olvera de La Cruz, Monica

    Soft materials can be used as building blocks of electronic devices with extraordinary properties. We demonstrate that an ionic analogue of the semiconductor field-effect transistor (FET) could be used for voltage and current amplifiers. Our theoretical model incorporates readily-available soft materials, such as conductive porous membranes and polymer electrolytes to represent a current-gating device that can be integrated in electronic circuits. By means of Nernst-Planck numerical simulations as well as an analytical approach towards expressions that describe steady-state currents, we find that the behavior in response to various input voltages can be categorized into ohmic, sub-threshold, and active modes. This is fully analogous to what is known for semiconductor FETs. Pivotal FET properties such as threshold voltage and transconductance must be related to half-cell redox potentials as well as polyelectrolyte and gate material properties. We further extend the analogy with semiconductor FETs through numerical simulations of elementary amplifier circuits in which we successfully substitute the semiconductor transistor by an ionic FET.


    Yadav Jaya


    Full Text Available Bipolar disorder is a chronic illness, which may require life-long treatment. Patients will spend 3-5 times more days in the depressed episode then in the manic phase. Due to this variability in episodes, polypharmacy is used quite frequently in practice, though the evidence to do this remains quite limited. Many positive and negative outcomes can occur from this practice. Bipolar disorder is the 6th leading cause of disability in the developed world among those between the ages 15 and 44 years age groups. Serotonin is one of the neurotransmitter in the brain, and one of that strongly affects the person mood. Clozapine (clozaril, olanzapine (zyperexa, risperidone (Risperdal, and ziprasidone (zeldox and the clozapine may be helpful as mood stabilizer for people who do not respond to lithium and anticonvulsant.

  15. Life expectancy in bipolar disorder

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh


    OBJECTIVE: Life expectancy in patients with bipolar disorder has been reported to be decreased by 11 to 20 years. These calculations are based on data for individuals at the age of 15 years. However, this may be misleading for patients with bipolar disorder in general as most patients have a later...... onset of illness. The aim of the present study was to calculate the remaining life expectancy for patients of different ages with a diagnosis of bipolar disorder. METHODS: Using nationwide registers of all inpatient and outpatient contacts to all psychiatric hospitals in Denmark from 1970 to 2012 we...... remaining life expectancy in bipolar disorder and that of the general population decreased with age, indicating that patients with bipolar disorder start losing life-years during early and mid-adulthood. CONCLUSIONS: Life expectancy in bipolar disorder is decreased substantially, but less so than previously...

  16. Bipolar Disorder and Cancer

    Sermin Kesebir; Arzu Bayrak


    Prevalence studies and studies on causation relations have shown that the relation between psychiatric disorders and chronic physical diseases is neglected. For heterogeneous diseases an increasing number of susceptibility variants are being defined. Alzheimer disease, bipolar disorder, breast and prostate cancer, coronary artery disease, Chron's disease, systemic lupus eritematosus, type 1 and type 2 diabetes mellitus are mentioned together with epigenetic concept. In acrocentric zone of chr...

  17. Treatment of bipolar disorder

    Geddes, John R.; Miklowitz, David J.


    We review recent developments in the acute and long-term treatment of bipolar disorder and identify promising future routes to therapeutic innovation. Overall, advances in drug treatment remain quite modest. Antipsychotic drugs are effective in the acute treatment of mania; their efficacy in the treatment of depression is variable with the clearest evidence for quetiapine. Despite their widespread use, considerable uncertainty and controversy remains about the use of antidepressant drugs in t...

  18. Bipolar Disorder in Children and Teens

    ... is in crisis. What do I do? Share Bipolar Disorder in Children and Teens Download PDF Download ePub ... brochure will give you more information. What is bipolar disorder? Bipolar disorder is a serious brain illness. It ...

  19. Prophylactic treatment in bipolar disorder

    Eroğlu, Meliha Zengin; Özpoyraz, Nurgül; Tamam, Lut


    Objective: The aim of this study was to determine the prophylactic treatment response and its relationship between clinical variables among the bipolar disorder patient group followed up in the Bipolar Disorder Unit of Psychiatry Department of Cukurova University Faculty of Medicine. Methods: One hundred patients, in euthymic period, diagnosed as bipolar disorder, were included in this study. “Affective Disorders Patient Registry Form” developed by our unit, SCID-I, Young Mani Rating Scale...

  20. Mathematical models of bipolar disorder

    Daugherty, D; Roque-Urrea, T; Urrea-Roque, J; DE TROYER, J; Wirkus, S; Porter, M. A.


    We use limit cycle oscillators to model bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about 1% of the United States adult population. We consider two non-linear oscillator models of a single bipolar patient. In both frameworks, we begin with an untreated individual and examine the mathematical effects and resulting biological consequences of treatment. We also briefly consider the dynamics of interacting bipolar II individuals using ...

  1. The Genetics of Bipolar Disorder

    Jennifer H Barnett; Smoller, Jordan W.


    Bipolar disorder is a mood disorder characterized by impairing episodes of mania and depression. Twin studies have established that bipolar disorder is among the most heritable of medical disorders and efforts to identify specific susceptibility genes have intensified over the past two decades. The search for genes influencing bipolar disorder has been complicated by a paucity of animal models, limited understanding of pathogenesis, and the genetic and phenotypic complexity of the syndrome. L...

  2. Mathematical Models of Bipolar Disorder

    Daugherty, Darryl; Roque-Urrea, Tairi; Urrea-Roque, John; Snyder, Jessica; Wirkus, Stephen; Mason A. Porter


    We use limit cycle oscillators to model Bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about one percent of the United States adult population. We consider two nonlinear oscillator models of a single bipolar patient. In both frameworks, we begin with an untreated individual and examine the mathematical effects and resulting biological consequences of treatment. We also briefly consider the dynamics of interacting bipolar II individual...

  3. Childhood trauma in bipolar disorder

    Watson, S; Gallagher, P.; Dougall, D.; R Porter; Moncrieff, J.; Ferrier, I. N.; Young, A. H.


    Objective: There has been little investigation of early trauma in bipolar disorder despite evidence that stress impacts on the course of this illness. We aimed to compare the rates of childhood trauma in adults with bipolar disorder to a healthy control group, and to investigate the impact of childhood trauma on the clinical course of bipolar disorder. Methods: Retrospective assessment of childhood trauma was conducted using the Childhood Trauma Questionnaire (CTQ) in 60 outpatients with bipo...

  4. Scientific attitudes towards bipolar disorders

    Mohammad-Hossein Biglu; Sahar Biglu


    Introduction: Bipolar disorder is a psychiatric condition that is also called manic-depressive disease. It causes unusual changes in mood, energy, activity levels, and the ability to carry out day-to-day tasks. In the present study, 3 sets of data were considered and analyzed: first, all papers categorized under Bipolar Disorders in Science Citation Index Expanded (SCI-E) database through 2001-2011; second, papers published by the international journal of Bipolar Disorders indexed in SCI-E d...

  5. Pediatrik Bipolar Bozuklukta Epidemiyoloji

    Caner Mutlu; Neslim Guvendeger Doksat; Ayten Erdogan


    Çocuk ve ergenlerde bipolar bozukluk tanısı giderek artış göstermektedir. Çocuk ve ergen popülasyonunda intihar girişiminde bulunanların önemli bir oranının bipolar bozukluğu olanlarda ortaya çıkıyor olması, bu hastalığın tanı ve tedavisini daha da önemli kılmaktadır. Özellikle ergenlik dönemi öncesi örneklemlerde açık tanı ölçütlerinin olmaması ve değerlendirmelerin belirtilere dayanılarak yapılmasından dolayı yanlış biçimde bipolar bozukluk tanısı konduğu ve yaygınlık oranlarının oldu-ğunda...

  6. A current-controlled PWM bipolar power supply for a magnet load

    The Advanced Photon Source, at Argonne National Laboratory will produce the world's brightest x-ray beams when it is complete. A number of correction magnets are used to maintain proper beam position. Basically, two different types of bipolar power supplies are used for all the correction magnets: one requires dc correction only, and the other requires dc and ac correction. Normally linear-mode power amplifiers would be used for the bipolar power supplies. However, linear-mode power amplifiers dissipate a substantial amount of power as heat, resulting in poor efficiency for their large size. In addition, most commercial bipolar power supplies are linear-mode and available for lower power levels. Therefore, for higher power levels it was necessary to design a bipolar power supply that uses switch-mode power conversion. This paper describes a control technique for a pulse-width-modulatcd bipolar power supply, which can deliver a controlled current, dc plus ac to a correction magnet. A design example of a 150A bipolar power supply is presented

  7. MMIC DHBT Common-Base Amplifier for 172 GHz

    Paidi, Vamsi; Griffith, Zack; Wei, Yun; Dahlstrom, Mttias; Urteaga, Miguel; Rodwell, Mark; Samoska, Lorene; Fung, King Man; Schlecht, Erich


    Figure 1 shows a single-stage monolithic microwave integrated circuit (MMIC) power amplifier in which the gain element is a double-heterojunction bipolar transistor (DHBT) connected in common-base configuration. This amplifier, which has been demonstrated to function well at a frequency of 172 GHz, is part of a continuing effort to develop compact, efficient amplifiers for scientific instrumentation, wide-band communication systems, and radar systems that will operate at frequencies up to and beyond 180 GHz. The transistor is fabricated from a layered structure formed by molecular beam epitaxy in the InP/InGaAs material system. A highly doped InGaAs base layer and a collector layer are fabricated from the layered structure in a triple mesa process. The transistor includes two separate emitter fingers, each having dimensions of 0.8 by 12 m. The common-base configuration was chosen for its high maximum stable gain in the frequency band of interest. The input-matching network is designed for high bandwidth. The output of the transistor is matched to a load line for maximum saturated output power under large-signal conditions, rather than being matched for maximum gain under small-signal conditions. In a test at a frequency of 172 GHz, the amplifier was found to generate an output power of 7.5 mW, with approximately 5 dB of large-signal gain (see Figure 2). Moreover, the amplifier exhibited a peak small-signal gain of 7 dB at a frequency of 176 GHz. This performance of this MMIC single-stage amplifier containing only a single transistor represents a significant advance in the state of the art, in that it rivals the 170-GHz performance of a prior MMIC three-stage, four-transistor amplifier. [The prior amplifier was reported in "MMIC HEMT Power Amplifier for 140 to 170 GHz" (NPO-30127), NASA Tech Briefs, Vol. 27, No. 11 (November 2003), page 49.] This amplifier is the first heterojunction- bipolar-transistor (HBT) amplifier built for medium power operation in this

  8. Bipolar Disorder and Diabetes Mellitus

    Sermin Kesebir


    Full Text Available Comorbid endocrine and cardiovascular situations with bipolar disorder usually result from the bipolar disorder itself or as a consequence of its treatment. With habits and lifestyle, genetic tendency and side effects, this situation is becoming more striking. Subpopulations of bipolar disorders patients should be considered at high risk for diabetes mellitus. The prevalence of diabetes mellitus in bipolar disorder may be three times greater than in the general population. Comorbidity of diabetes causes a pathophysiological overlapping in the neurobiological webs of bipolar cases. Signal mechanisms of glycocorticoid/insulin and immunoinflammatory effector systems are junction points that point out the pathophysiology between bipolar disorder and general medical cases susceptible to stress. Glycogen synthetase kinase (GSK-3 is a serine/treonine kinase and inhibits the transport of glucose stimulated by insulin. It is affected in diabetes, cancer, inflammation, Alzheimer disease and bipolar disorder. Hypoglycemic effect of lithium occurs via inhibiting glycogen synthetase kinase. When comorbid with diabetes, the other disease -for example bipolar disorder, especially during its acute manic episodes-, causes a serious situation that presents its influences for a lifetime. Choosing pharmacological treatment and treatment adherence are another important interrelated areas. The aim of this article is to discuss and review the etiological, clinical and therapeutic properties of diabetes mellitus and bipolar disorder comorbidity.

  9. [Antipsychotics in bipolar disorders].

    Vacheron-Trystram, M-N; Braitman, A; Cheref, S; Auffray, L


    This article is a review of the various treatments that are currently available, in particular in France, for the treatment of bipolar disorders. This article specifically addresses the use of novel antipsychotic agents as alternative therapy to a lithium therapy and/or the use of conventional antipsychotics. The prevalence of bipolar disorder over a lifetime is around 1% of the general population. Bipolar disorder consists of alternating depressive and manic episodes. It mainly affects younger subjects, and is often associated with alcohol and drug addictions. There are two main subtypes of bipolar disorder. According to the DSM IV-R, type 1 of bipolar disorder is characterised when at least one manic episode (or a mixed episode) has been diagnosed. Type 2 of bipolar disorder is related to patients enduring recurrent depressive episodes but no manic episode. Type 2 affects women more frequently as opposed to type 1 affecting individuals of both sexes. Manic-depressive disorder (or cyclo-thymic disorder) appears in relation to patients who has never suffered manic episode, mixed episode or severe depressive episode but have undergone numerous periods with some symptoms of depression and hypomanic symptoms over a two-year period during which any asymptomatic periods last no longer than two months. The average age of the person going through a first episode (often a depressive one) is 20 years-old. Untreated bipolar patients may endure more than ten manic or depressive episodes. Finally, in relation to 10 to 20% of patients, the bipolar disorder will turn into a fast cycle form, either spontaneously or as a result of certain medical treatments. Psychiatrists are now able to initiate various treating strategies which are most likely to be effective as a result of the identification of clinical subtypes of the bipolar disorder. Lithium therapy has been effectively and acutely used for patients with pure or elated mania and its prophylaxis. However, lithium medication

  10. Differentiation without Distancing. Explaining Bi-Polarization of Opinions without Negative Influence

    Maes, Michael; Flache, Andreas


    Explanations of opinion bi-polarization hinge on the assumption of negative influence, individuals' striving to amplify differences to disliked others. However, empirical evidence for negative influence is inconclusive, which motivated us to search for an alternative explanation. Here, we demonstrat

  11. RF Power Amplifier Analysis

    M. Lokay; K. Pelikan


    The special program is presented for the demonstration of RF power transistor amplifiers for the purposes of the high-school education in courses of radio transmitters. The program is written in Turbo Pascal 6. 0 and enables to study the waveforms in selected points of the amplifier and to draw the trajectories of the working point in a plot of output transistor characteristics.

  12. Amplifier improvement circuit

    Sturman, J.


    Stable input stage was designed for the use with a integrated circuit operational amplifier to provide improved performance as an instrumentation-type amplifier. The circuit provides high input impedance, stable gain, good common mode rejection, very low drift, and low output impedance.

  13. Genetics of bipolar disorder

    Kerner B


    Full Text Available Berit Kerner Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, USA Abstract: Bipolar disorder is a common, complex genetic disorder, but the mode of transmission remains to be discovered. Many researchers assume that common genomic variants carry some risk for manifesting the disease. The research community has celebrated the first genome-wide significant associations between common single nucleotide polymorphisms (SNPs and bipolar disorder. Currently, attempts are under way to translate these findings into clinical practice, genetic counseling, and predictive testing. However, some experts remain cautious. After all, common variants explain only a very small percentage of the genetic risk, and functional consequences of the discovered SNPs are inconclusive. Furthermore, the associated SNPs are not disease specific, and the majority of individuals with a “risk” allele are healthy. On the other hand, population-based genome-wide studies in psychiatric disorders have rediscovered rare structural variants and mutations in genes, which were previously known to cause genetic syndromes and monogenic Mendelian disorders. In many Mendelian syndromes, psychiatric symptoms are prevalent. Although these conditions do not fit the classic description of any specific psychiatric disorder, they often show nonspecific psychiatric symptoms that cross diagnostic boundaries, including intellectual disability, behavioral abnormalities, mood disorders, anxiety disorders, attention deficit, impulse control deficit, and psychosis. Although testing for chromosomal disorders and monogenic Mendelian disorders is well established, testing for common variants is still controversial. The standard concept of genetic testing includes at least three broad criteria that need to be fulfilled before new genetic tests should be introduced: analytical validity, clinical validity, and clinical utility. These criteria are

  14. Scientific attitudes towards bipolar disorders

    Mohammad-Hossein Biglu


    Full Text Available Introduction: Bipolar disorder is a psychiatric condition that is also called manic-depressive disease. It causes unusual changes in mood, energy, activity levels, and the ability to carry out day-to-day tasks. In the present study, 3 sets of data were considered and analyzed: first, all papers categorized under Bipolar Disorders in Science Citation Index Expanded (SCI-E database through 2001-2011; second, papers published by the international journal of Bipolar Disorders indexed in SCI-E during a period of 11 years; and third, all papers distributed by the international journal of Bipolar Disorders indexed in MEDLINE during the period of study. Methods: The SCI-E database was used to extract all papers indexed with the topic of Bipolar Disorders as well as all papers published by The International Journal of Bipolar Disorders. Extraction of data from MEDLINE was restricted to the journals name from setting menu. The Science of Science Tool was used to map the co-authorship network of papers published by The International Journal of Bipolar Disorders through 2009-2011. Results: Analysis of data showed that the majority of publications in the subject area of bipolar disorders indexed in SCI-E were published by The International Journal of Bipolar Disorders. Although journal articles consisted of 59% of the total publication type in SCI-E, 65% of publications distributed by The Journal of Bipolar Disorders were in the form of meetingabstracts. Journal articles consisted of only 23% of the total publications. USA was the leading country regarding sharing data in the field of bipolar disorders followed by England, Canada, and Germany. Conclusion: The editorial policy of The International Journal of Bipolar Disorders has been focused on new themes and new ways of researching in the subject area of bipolar disorder. Regarding the selection of papers for indexing, the SCI-E database selects data more comprehensively than MEDLINE. The number of papers

  15. Tobacco Use in Bipolar Disorder

    Thomson, Daniel; Berk, Michael; Dodd, Seetal; Rapado-Castro, Marta; Quirk, Shae E.; Ellegaard, Pernille K.; Berk, Lesley; Dean, Olivia M.


    Tobacco use in mental health in general and bipolar disorder in particular remains disproportionally common, despite declining smoking rates in the community. Furthermore, interactions between tobacco use and mental health have been shown, indicating the outcomes for those with mental health disorders are impacted by tobacco use. Factors need to be explored and addressed to improve outcomes for those with these disorders and target specific interventions for people with psychiatric illness to cease tobacco smoking. In the context of bipolar disorder, this review explores; the effects of tobacco smoking on symptoms, quality of life, suicidal behaviour, the biological interactions between tobacco use and bipolar disorder, the interactions between tobacco smoking and psychiatric medications, rates and factors surrounding tobacco smoking cessation in bipolar disorder and suggests potential directions for research and clinical translation. The importance of this review is to bring together the current understanding of tobacco use in bipolar disorder to highlight the need for specific intervention. PMID:25912533

  16. Bipolar Disorder and Childhood Trauma

    Evrim Erten


    Full Text Available Bipolar disorder is a chronic disorder in which irregular course of depressive, mania or mixed episodes or a complete recovery between episodes can be observed. The studies about the effects of traumatic events on bipolar disorder showed that they had significant and long-term effects on the symptoms of the disorder. Psychosocial stress might change the neurobiology of bipolar disorder over time. The studies revealed that the traumatic events could influence not only the onset of the disorder but also the course of the disorder and in these patients the rate of suicide attempt and comorbid substance abuse might increase. Bipolar patients who had childhood trauma had an earlier onset, higher number of episodes and comorbid disorders. In this review, the relationship between childhood trauma and bipolar disorder is reviewed. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2015; 7(2: 157-165

  17. Semiconductor optical amplifiers

    Dutta, Niloy K


    This invaluable look provides a comprehensive treatment of design and applications of semiconductor optical amplifiers (SOA). SOA is an important component for optical communication systems. It has applications as in-line amplifiers and as functional devices in evolving optical networks. The functional applications of SOAs were first studied in the early 1990's, since then the diversity and scope of such applications have been steadily growing. This is the second edition of a book on Semiconductor Optical Amplifiers first published in 2006 by the same authors. Several chapters and sections rep

  18. Bipolar pulse forming line

    Rhodes, Mark A.


    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.

  19. Current feedback operational amplifiers and their applications

    Senani, Raj; Singh, A K; Singh, V K


    This book describes a variety of current feedback operational amplifier (CFOA) architectures and their applications in analog signal processing/generation. Coverage includes a comprehensive survey of commercially available, off-the-shelf integrated circuit CFOAs, as well as recent advances made on the design of CFOAs, including design innovations for bipolar and CMOS CFOAs.  This book serves as a single-source reference to the topic, as well as a catalog of over 200 application circuits which would be useful not only for students, educators and researchers in apprising them about the recent developments in the area but would also serve as a comprehensive repertoire of useful circuits for practicing engineers who might be interested in choosing an appropriate CFOA-based topology for use in a given application.

  20. Complement and Isomorphism on Bipolar Fuzzy Graphs

    Ali Asghar Talebi


    Full Text Available In this paper, we discuss some properties of the self complement and self weak complement bipolar fuzzy graphs, and get a sufficient condition for a bipolar fuzzy graph to be the self weak complement bipolar fuzzy graph. Also we investigate relations between operations union, join, and complement on bipolar fuzzy graphs.

  1. Complement and Isomorphism on Bipolar Fuzzy Graphs

    Ali Asghar Talebi; Hossein Rashmanlou


    In this paper, we discuss some properties of the self complement and self weak complement bipolar fuzzy graphs, and get a sufficient condition for a bipolar fuzzy graph to be the self weak complement bipolar fuzzy graph. Also we investigate relations between operations union, join, and complement on bipolar fuzzy graphs.

  2. RF Power Amplifier Analysis

    M. Lokay


    Full Text Available The special program is presented for the demonstration of RF power transistor amplifiers for the purposes of the high-school education in courses of radio transmitters. The program is written in Turbo Pascal 6. 0 and enables to study the waveforms in selected points of the amplifier and to draw the trajectories of the working point in a plot of output transistor characteristics.

  3. Noise in Optical Amplifiers

    Jeppesen, Palle


    Noise in optical amplifiers is discussed on the basis of photons and electromagntic fields. Formulas for quantum noise from spontaneous emission, signal-spontaneous beat noise and spontaneous-spontaneous beat noise are derived.......Noise in optical amplifiers is discussed on the basis of photons and electromagntic fields. Formulas for quantum noise from spontaneous emission, signal-spontaneous beat noise and spontaneous-spontaneous beat noise are derived....

  4. Charge-sensitive amplifier

    Startsev V. I.; Yampolsky Ju. S.


    The authors consider design and circuit design techniques of reduction of the influence of the pyroelectric effect on operation of the charge sensitive amplifiers. The presented experimental results confirm the validity of the measures taken to reduce the impact of pyroelectric currents. Pyroelectric currents are caused by the influence of the temperature gradient on the piezoelectric sensor and on the output voltage of charge sensitive amplifiers.

  5. E-537 MWPC amplifier

    The design of a fast MWPC amplifier for the beam chambers and the absorber chamber is completed and all parts are on order. A prototype 16 channel board has been built and satisfactorily tested. Artwork is completed for the board and out to be photographed. The board fabrication contract has been let. Listed below is a summary of the amplifier characteristics as well as test results obtained with the prototype

  6. Electrospun Amplified Fiber Optics

    Morello, Giovanni; Camposeo, Andrea; Moffa, Maria; Pisignano, Dario


    A lot of research is focused on all-optical signal processing, aiming to obtain effective alternatives to existing data transmission platforms. Amplification of light in fiber optics, such as in Erbium-doped fiber amplifiers, is especially important for an efficient signal transmission. However, the complex fabrication methods, involving high-temperature processes performed in highly pure environment, slow down the fabrication and make amplified components expensive with respect to an ideal, ...

  7. Effect of collector bias current on the linearity of common-emitter BJT amplifiers

    Using a Volterra series, an explicit formula is derived for the connection between input 3rd-order intercept point and collector bias current (ICQ) in a common-emitter bipolar junction transistor amplifier. The analysis indicates that the larger ICQ is, the more linear the amplifier is. Furthermore, this has been verified by experiment. This study also integrates a method called dynamic bias current for expanding the dynamic range of an LNA (low noise amplifier) as an application of the analysis result obtained above. IMR3 (3rd-order intermodulation rate) is applied to evaluate the LNA's performance with and without adopting this method in this study. (semiconductor devices)

  8. Burden of Illness in Bipolar Depression

    Manning, J. Sloan


    Bipolar depression is the underrecognized and unappreciated phase of bipolar disorder. Nevertheless, bipolar depression is responsible for much of the morbidity and mortality associated with the disorder. Depressive symptoms are far more prevalent than hypomanic or manic symptoms in bipolar patients, and they are associated with a heavier burden of illness, including reduced functioning, increased risk of suicidal acts, and high economic costs. Because most patients with bipolar disorder pres...

  9. Asenapine for bipolar disorder

    Scheidemantel T


    Full Text Available Thomas Scheidemantel,1 Irina Korobkova,2 Soham Rej,3,4 Martha Sajatovic1,2 1University Hospitals Case Medical Center, 2Case Western Reserve University School of Medicine, Cleveland, OH, USA; 3Department of Psychiatry, University of Toronto, Toronto, ON, 4Geri PARTy Research Group, Jewish General Hospital, Montreal, QC, Canada Abstract: Asenapine (Saphris® is an atypical antipsychotic drug which has been approved by the US Food and Drug Administration for the treatment of schizophrenia in adults, as well as the treatment of acute manic or mixed episodes of bipolar I in both adult and pediatric populations. Asenapine is a tetracyclic drug with antidopaminergic and antiserotonergic activity with a unique sublingual route of administration. In this review, we examine and summarize the available literature on the safety, efficacy, and tolerability of asenapine in the treatment of bipolar disorder (BD. Data from randomized, double-blind trials comparing asenapine to placebo or olanzapine in the treatment of acute manic or mixed episodes showed asenapine to be an effective monotherapy treatment in clinical settings; asenapine outperformed placebo and showed noninferior performance to olanzapine based on improvement in the Young Mania Rating Scale scores. There are limited data available on the use of asenapine in the treatment of depressive symptoms of BD, or in the maintenance phase of BD. The available data are inconclusive, suggesting the need for more robust data from prospective trials in these clinical domains. The most commonly reported adverse effect associated with use of asenapine is somnolence. However, the somnolence associated with asenapine use did not cause significant rates of discontinuation. While asenapine was associated with weight gain when compared to placebo, it appeared to be modest when compared to other atypical antipsychotics, and its propensity to cause increases in hemoglobin A1c or serum lipid levels appeared to be

  10. High Transconductance AlGaN/GaN HEMT Growth on Sapphire Substrates%高跨导AlGaN/GaN HEMT器件

    肖冬萍; 刘键; 魏珂; 和致经; 刘新宇; 吴德馨


    The fabrication and characterization of AlGaN/GaN high electron mobility transistors (HEMT) grown on sapphire substrates by MBE are described.These 1.0μm gate-length devices exhibit a maximum drain current density as high as 1000mA/mm and a maximum transconductance of 198mS/mm.In sharp contrast to high current density HEMT fabricated on sapphire substrates,the extrinsic transconductance versus gate-to-source voltage profiles exhibit the broad plateaus over a large voltage swing.A unity gain cutoff frequency (fT) of 18.7GHz and a maximum frequency of oscillation (fmax) of 19.1GHz are also obtained.%报道了生长在蓝宝石衬底上的AlGaN/GaN HEMT器件的制造工艺以及在室温下器件的性能.器件的栅长为1.0μm,源漏间距为4.0μm.器件的最大电流密度达到1000mA/mm,最大跨导高达198mS/mm,转移特性曲线表现出增益带宽较宽的特点.同时由所测得的S参数推出栅长为1.0μm器件的截止频率(fT)和最高振荡频率(fmax)分别为18.7GHz和19.1GHz.

  11. Quetiapine monotherapy for bipolar depression



    Michael E ThaseDepartments of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA, USA; the Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA; and the University of Pittsburgh Medical Center, Pittsburgh, PA, USAAbstract: Bipolar depression is more common, disabling, and difficult-to-treat than the manic and hypomanic phases that define bipolar disorder. Unlike the treatment of so-called “unipolar” depressions, antidepressants gener...

  12. Sleep Disturbances in Bipolar Disorder

    Cátia Alves Moreira; Pedro Afonso


    Background: Bipolar disorder, characterized by episodes of mania, hypomania and depression is associated with sleep disturbances and circadian rhythm disruption. These changes have significant impact on quality of life and in the disease prognosis. Aims: Review of the main sleep disturbances observed in the bipolar disorder, their clinical impact and the hypothetical pathophysiological mechanisms involved. Methods: We conducted a non-systematic review of the literature in English through rese...

  13. : Genetic heterogeneity of bipolar disorder

    Mathieu, Flavie; Dizier, Marie-Hélène; Etain, Bruno; Jamain, Stéphane; Rietschel, Marcella; Maier, Wolfgang; Albus, Margot; Mckeon, Patrick; Roche, Siobhan; Blackwood, Douglas; Muir, Walter,; Henry, Chantal; Malafosse, Alain; Preisig, Martin; Ferrero, François


    Bipolar disorder has a genetic component, but the mode of inheritance remains unclear. A previous genome scan conducted in 70 European families led to detect eight regions linked to bipolar disease. Here, we present an investigation of whether the phenotypic heterogeneity of the disorder corresponds to genetic heterogeneity in these regions using additional markers and an extended sample of families. The MLS statistic was used for linkage analyses. The predivided sample test and the maximum l...

  14. Bipolar spectrum disorders. New perspectives.

    Piver, Andre; Yatham, Lakshmi N.; Raymond W. Lam


    OBJECTIVE: To review new perspectives on diagnosis, clinical features, epidemiology, and treatment of bipolar II and related disorders. QUALITY OF EVIDENCE: Articles were identified by searching MEDLINE and ClinPSYCH from January 1994 to August 2001 using the key words bipolar disorder, type II or 2; hypomania; spectrum; or variants. Reference lists from articles were reviewed. Overall, the quality of evidence was not high; we found no randomized controlled trials that specifically addressed ...

  15. Ultra-low noise miniaturized neural amplifier with hardware averaging

    Dweiri, Yazan M.; Eggers, Thomas; McCallum, Grant; Durand, Dominique M.


    Objective. Peripheral nerves carry neural signals that could be used to control hybrid bionic systems. Cuff electrodes provide a robust and stable interface but the recorded signal amplitude is small (<3 μVrms 700 Hz-7 kHz), thereby requiring a baseline noise of less than 1 μVrms for a useful signal-to-noise ratio (SNR). Flat interface nerve electrode (FINE) contacts alone generate thermal noise of at least 0.5 μVrms therefore the amplifier should add as little noise as possible. Since mainstream neural amplifiers have a baseline noise of 2 μVrms or higher, novel designs are required. Approach. Here we apply the concept of hardware averaging to nerve recordings obtained with cuff electrodes. An optimization procedure is developed to minimize noise and power simultaneously. The novel design was based on existing neural amplifiers (Intan Technologies, LLC) and is validated with signals obtained from the FINE in chronic dog experiments. Main results. We showed that hardware averaging leads to a reduction in the total recording noise by a factor of 1/√N or less depending on the source resistance. Chronic recording of physiological activity with FINE using the presented design showed significant improvement on the recorded baseline noise with at least two parallel operation transconductance amplifiers leading to a 46.1% reduction at N = 8. The functionality of these recordings was quantified by the SNR improvement and shown to be significant for N = 3 or more. The present design was shown to be capable of generating <1.5 μVrms total recording baseline noise when connected to a FINE placed on the sciatic nerve of an awake animal. An algorithm was introduced to find the value of N that can minimize both the power consumption and the noise in order to design a miniaturized ultralow-noise neural amplifier. Significance. These results demonstrate the efficacy of hardware averaging on noise improvement for neural recording with cuff electrodes, and can accommodate the

  16. A micropower electrocardiogram amplifier.

    Fay, L; Misra, V; Sarpeshkar, R


    We introduce an electrocardiogram (EKG) preamplifier with a power consumption of 2.8 muW, 8.1 muVrms input-referred noise, and a common-mode rejection ratio of 90 dB. Compared to previously reported work, this amplifier represents a significant reduction in power with little compromise in signal quality. The improvement in performance may be attributed to many optimizations throughout the design including the use of subthreshold transistor operation to improve noise efficiency, gain-setting capacitors versus resistors, half-rail operation wherever possible, optimal power allocations among amplifier blocks, and the sizing of devices to improve matching and reduce noise. We envision that the micropower amplifier can be used as part of a wireless EKG monitoring system powered by rectified radio-frequency energy or other forms of energy harvesting like body vibration and body heat. PMID:23853270

  17. A vircator amplifier

    A cavity vircator has demonstrated that formation of a virtual cathode in a cavity can improve microwave production efficiency and narrow the radiation bandwidth. When the virtual cathode radiates the microwave fields grow from noise. For each cavity, there is only one or a limited number of allowable modes for a given frequency. In this paper, a novel device - a vircator amplifier is described. The device consists of a relativistic magnetron and a cavity vircator with both devices powered by a 1 MeV, 3 Ω, 65 ns FWHM pulser. The idea is to inject a signal from the magnetron before and during virtual cathode formation in a cavity. The injected signal should lock the frequency and enhance electron bunching and therefore improve efficiency further. Experiments underway to evaluate the amplifier operating characteristics are discussed. The applicability of vircator amplifiers to the next generation of high-power microwave devices are addressed

  18. Threat sensitivity in bipolar disorder.

    Muhtadie, Luma; Johnson, Sheri L


    Life stress is a major predictor of the course of bipolar disorder. Few studies have used laboratory paradigms to examine stress reactivity in bipolar disorder, and none have assessed autonomic reactivity to laboratory stressors. In the present investigation we sought to address this gap in the literature. Participants, 27 diagnosed with bipolar I disorder and 24 controls with no history of mood disorder, were asked to complete a complex working memory task presented as "a test of general intelligence." Self-reported emotions were assessed at baseline and after participants were given task instructions; autonomic physiology was assessed at baseline and continuously during the stressor task. Compared to controls, individuals with bipolar disorder reported greater increases in pretask anxiety from baseline and showed greater cardiovascular threat reactivity during the task. Group differences in cardiovascular threat reactivity were significantly correlated with comorbid anxiety in the bipolar group. Our results suggest that a multimethod approach to assessing stress reactivity-including the use of physiological parameters that differentiate between maladaptive and adaptive profiles of stress responding-can yield valuable information regarding stress sensitivity and its associations with negative affectivity in bipolar disorder. (PsycINFO Database Record (c) 2015 APA, all rights reserved). PMID:25688436

  19. Quetiapine monotherapy for bipolar depression

    Michael E Thase


    Full Text Available Michael E ThaseDepartments of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA, USA; the Philadelphia Veterans Affairs Medical Center, Philadelphia, PA, USA; and the University of Pittsburgh Medical Center, Pittsburgh, PA, USAAbstract: Bipolar depression is more common, disabling, and difficult-to-treat than the manic and hypomanic phases that define bipolar disorder. Unlike the treatment of so-called “unipolar” depressions, antidepressants generally are not indicated as monotherapies for bipolar depressions and recent studies suggest that - even when used in combination with traditional mood stabilizers – antidepressants may have questionable value for bipolar depression. The current practice is that mood stabilizers are initiated first as monotherapies; however, the antidepressant efficacy of lithium and valproate is modest at best. Within this context the role of atypical antipsychotics is being evaluated. The combination of olanzapine and the antidepressant fluoxetine was the first treatment to receive regulatory approval in the US specifically for bipolar I depression. Quetiapine was the second medication to be approved for this indication, largely as the result of two pivotal trials known by the acronyms of BOLDER (BipOLar DEpRession I and II. Both studies demonstrated that two doses of quetiapine (300 mg and 600 mg given once daily at bedtime were significantly more effective than placebo, with no increased risk of patients switching into mania. Pooling the two studies, quetiapine was effective for both bipolar I and bipolar II depressions and for patients with (and without a history of rapid cycling. The two doses were comparably effective in both studies. Although the efficacy of quetiapine monotherapy has been established, much additional research is necessary. Further studies are needed to more fully investigate dose-response relationships and comparing quetiapine monotherapy to other mood stabilizers

  20. Design and development of 1 KW solid state RF amplifier

    Since low power tube based RF amplifiers are complicated, occupy a large space and are bulky, the efforts are on to develop indigenously 1 KW solid state technology based RF Power amplifier. A power level of 1KW is chosen for the initial design because RF power Mosfets upto 250 watt are easily available and by clubbing 3-4 stages the power level of 1 KW can be made. Presently design and testing of 100-watt stage is in progress. The first 2 stages are designed to give 5 Watt RF power using bipolar transistors and are operated in CE, Class A to provide low noise level at the output of the system. The 3rd stage will be MOSFET based MRF 174, which is ideally suited for class A operation and is designed for 100 Watt RF power. The last stage will be MOSFET based ARF446 power MOSFET in TO-247 plastic package. This amplifier will be used in the classical push- pull configuration. This paper describes the design aspects as well as the test results of 100 watt amplifier on 50 Ohm dummy load along with the specifications, design criteria, circuit used, operating parameters of 1 KW Solid State RF power amplifier to be used as driver for 91.2 MHz, 1.5 MW stage for ICRH experiments on SST-1 tokamak .

  1. An Overview of Solid-State Integrated Circuit Amplifiers in the Submillimeter-Wave and THz Regime

    Samoska, Lorene A.


    We present an overview of solid-state integrated circuit amplifiers approaching terahertz frequencies based on the latest device technologies which have emerged in the past several years. Highlights include the best reported data from heterojunction bipolar transistor (HBT) circuits, high electron mobility transistor (HEMT) circuits, and metamorphic HEMT (mHEMT) amplifier circuits. We discuss packaging techniques for the various technologies in waveguide modules and describe the best reported...

  2. Integrated neurobiology of bipolar disorder

    Vladimir eMaletic


    Full Text Available From a neurobiological perspective there is no such thing as bipolar disorder. Rather, it is almost certainly the case that many somewhat similar, but subtly different, pathological conditions produce a disease state that we currently diagnose as bipolarity. This heterogeneity—reflected in the lack of synergy between our current diagnostic schema and our rapidly advancing scientific understanding of the condition—limits attempts to articulate an integrated perspective on bipolar disorder. However, despite these challenges, scientific findings in recent years are beginning to offer a provisional unified field theory of the disease. This theory sees bipolar disorder as a suite of related neurodevelopmental conditions with interconnected functional abnormalities that often appear early in life and worsen over time. In addition to accelerated loss of volume in brain areas known to be essential for mood regulation and cognitive function, consistent findings have emerged at a cellular level, providing evidence that bipolar disorder is reliably associated with dysregulation of glial-neuronal interactions. Among these glial elements are microglia—the brain’s primary immune elements, which appear to be overactive in the context of bipolarity. Multiple studies now indicate that inflammation is also increased in the periphery of the body in both the depressive and manic phases of the illness, with at least some return to normality in the euthymic state. These findings are consistent with changes in the HPA axis, which are known to drive inflammatory activation. In summary, the very fact that no single gene, pathway or brain abnormality is likely to ever account for the condition is itself an extremely important first step in better articulating an integrated perspective on both its ontological status and pathogenesis. Whether this perspective will translate into the discovery of innumerable more homogeneous forms of bipolarity is one of the great

  3. Continuous-time ΣΔ ADC with implicit variable gain amplifier for CMOS image sensor.

    Tang, Fang; Bermak, Amine; Abbes, Amira; Benammar, Mohieddine Amor


    This paper presents a column-parallel continuous-time sigma delta (CTSD) ADC for mega-pixel resolution CMOS image sensor (CIS). The sigma delta modulator is implemented with a 2nd order resistor/capacitor-based loop filter. The first integrator uses a conventional operational transconductance amplifier (OTA), for the concern of a high power noise rejection. The second integrator is realized with a single-ended inverter-based amplifier, instead of a standard OTA. As a result, the power consumption is reduced, without sacrificing the noise performance. Moreover, the variable gain amplifier in the traditional column-parallel read-out circuit is merged into the front-end of the CTSD modulator. By programming the input resistance, the amplitude range of the input current can be tuned with 8 scales, which is equivalent to a traditional 2-bit preamplification function without consuming extra power and chip area. The test chip prototype is fabricated using 0.18 μm CMOS process and the measurement result shows an ADC power consumption lower than 63.5 μW under 1.4 V power supply and 50 MHz clock frequency. PMID:24772012

  4. Targeting astrocytes in bipolar disorder.

    Peng, Liang; Li, Baoman; Verkhratsky, Alexei


    Astrocytes are homeostatic cells of the central nervous system, which are critical for development and maintenance of synaptic transmission and hence of synaptically connected neuronal ensembles. Astrocytic densities are reduced in bipolar disorder, and therefore deficient astroglial function may contribute to overall disbalance in neurotransmission and to pathological evolution. Classical anti-bipolar drugs (lithium salts, valproic acid and carbamazepine) affect expression of astroglial genes and modify astroglial signalling and homeostatic cascades. Many effects of both antidepressant and anti-bipolar drugs are exerted through regulation of glutamate homeostasis and glutamatergic transmission, through K(+) buffering, through regulation of calcium-dependent phospholipase A2 (that controls metabolism of arachidonic acid) or through Ca(2+) homeostatic and signalling pathways. Sometimes anti-depressant and anti-bipolar drugs exert opposite effects, and some effects on gene expression in drug treated animals are opposite in neurones vs. astrocytes. Changes in the intracellular pH induced by anti-bipolar drugs affect uptake of myo-inositol and thereby signalling via inositoltrisphosphate (InsP3), this being in accord with one of the main theories of mechanism of action for these drugs. PMID:27015045

  5. Imunologia do transtorno bipolar Immunology of bipolar disorder

    Izabela Guimarães Barbosa; Rodrigo Barreto Huguet; Fernando Silva Neves; Moisés Evandro Bauer; Antônio Lúcio Teixeira


    OBJETIVO: Pesquisas recentes têm implicado fatores imunes na patogênese de diversos transtornos neuropsiquiátricos. O objetivo do presente trabalho é revisar os trabalhos que investigaram a associação entre transtorno bipolar e alterações em parâmetros imunes. MÉTODOS: Artigos que incluíam as palavras-chave: "bipolar disorder", "mania", "immunology", "cytokines", "chemokines", "interleukins", "interferon" e "tumor necrosis factor" foram selecionados em uma revisão sistemática da literatura. A...


    Noe, J.B.


    A temperature stabilized transistor amplifier having a pair of transistors coupled in cascade relation that are capable of providing amplification through a temperature range of - 100 un. Concent 85% F to 400 un. Concent 85% F described. The stabilization of the amplifier is attained by coupling a feedback signal taken from the emitter of second transistor at a junction between two serially arranged biasing resistances in the circuit of the emitter of the second transistor to the base of the first transistor. Thus, a change in the emitter current of the second transistor is automatically corrected by the feedback adjustment of the base-emitter potential of the first transistor and by a corresponding change in the base-emitter potential of the second transistor. (AEC)

  7. Principal modes in fiber amplifiers

    Fridman, Moti; Dubinskii, Mark; Friesem, Asher A; Davidson, Nir


    The dynamics of the state of polarization in single mode and multimode fiber amplifiers are presented. The experimental results reveal that although the state of polarizations at the output can vary over a large range when changing the temperatures of the fiber amplifiers, the variations are significantly reduced when resorting to the principal states of polarization in single mode fiber amplifiers and principal modes in multimode fiber amplifiers.

  8. Helical Fiber Amplifier

    Koplow, Jeffrey P.; Kliner, Dahy; Goldberg, Lew


    A multi-mode gain fiber is provided which affords substantial improvements in the maximum pulse energy, peak power handling capabilities, average output power, and/or pumping efficiency of fiber amplifier and laser sources while maintaining good beam quality (comparable to that of a conventional single-mode fiber source). These benefits are realized by coiling the multimode gain fiber to induce significant bend loss for all but the lowest-order mode(s).

  9. Mathematical models of bipolar disorder

    Daugherty, Darryl; Roque-Urrea, Tairi; Urrea-Roque, John; Troyer, Jessica; Wirkus, Stephen; Porter, Mason A.


    We use limit cycle oscillators to model bipolar II disorder, which is characterized by alternating hypomanic and depressive episodes and afflicts about 1% of the United States adult population. We consider two non-linear oscillator models of a single bipolar patient. In both frameworks, we begin with an untreated individual and examine the mathematical effects and resulting biological consequences of treatment. We also briefly consider the dynamics of interacting bipolar II individuals using weakly-coupled, weakly-damped harmonic oscillators. We discuss how the proposed models can be used as a framework for refined models that incorporate additional biological data. We conclude with a discussion of possible generalizations of our work, as there are several biologically-motivated extensions that can be readily incorporated into the series of models presented here.

  10. Radio Frequency Solid State Amplifiers

    Jacob, J


    Solid state amplifiers are being increasingly used instead of electronic vacuum tubes to feed accelerating cavities with radio frequency power in the 100 kW range. Power is obtained from the combination of hundreds of transistor amplifier modules. This paper summarizes a one hour lecture on solid state amplifiers for accelerator applications.

  11. Social support and bipolar disorder

    Paula Mendonça Studart; Severino Bezerra Filho; Ana Beatriz Didier Studart; Amanda Galvão-de Almeida; Ângela Miranda-Scippa


    Background Bipolar disorder is a chronic condition that affects the functioning of its carriers in many different ways, even when treated properly. Therefore, it’s also important to identify the psychosocial aspects that could contribute to an improvement of this population’s quality of life.Objective Carry out a literature review on the role of social support in cases of bipolar disorder.Method A research on the following online databases PubMed, Lilacs and SciELO was conducted by using the ...

  12. Bipolar dislocation of the clavicle

    Wei Jiang


    Full Text Available Bipolar dislocation of the clavicle at acromioclavicular and sternoclavicular joint is an uncommon traumatic injury. The conservative treatments adopted in the past is associated with redislocation dysfunction and deformity. A 41 years old lady with bipolar dislocation of right shoulder is treated surgically by open reduction and internal fixation by oblique T-plate at sternoclavicular joint and Kirschner wire stabilization at acromioclavicular joint. The patient showed satisfactory recovery with full range of motion of the right shoulder and normal muscular strength. The case reported in view of rarity and at 2 years followup.

  13. Bipolar dislocation of the clavicle.

    Jiang, Wei; Gao, Shu-Guang; Li, Yu-Sheng; Lei, Guang-Hua


    Bipolar dislocation of the clavicle at acromioclavicular and sternoclavicular joint is an uncommon traumatic injury. The conservative treatments adopted in the past is associated with redislocation dysfunction and deformity. A 41 years old lady with bipolar dislocation of right shoulder is treated surgically by open reduction and internal fixation by oblique T-plate at sternoclavicular joint and Kirschner wire stabilization at acromioclavicular joint. The patient showed satisfactory recovery with full range of motion of the right shoulder and normal muscular strength. The case reported in view of rarity and at 2 years followup. PMID:23325981

  14. Refractory bipolar disorder and neuroprogression.

    da Costa, Sabrina C; Passos, Ives C; Lowri, Caroline; Soares, Jair C; Kapczinski, Flavio


    Immune activation and failure of physiologic compensatory mechanisms over time have been implicated in the pathophysiology of illness progression in bipolar disorder. Recent evidence suggests that such changes are important contributors to neuroprogression and may mediate the cross-sensitization of episode recurrence, trauma exposure and substance use. The present review aims to discuss the potential factors related to bipolar disorder refractoriness and neuroprogression. In addition, we will discuss the possible impacts of early therapeutic interventions as well as the alternative approaches in late stages of the disorder. PMID:26368941

  15. Gate length and temperature dependence of negative differential transconductance in silicon quantum well metal-oxide-semiconductor field-effect transistors

    Introducing quantum transport into silicon transistors in a manner compatible with industrial fabrication has the potential to transform the performance horizons of large scale integrated silicon devices and circuits. Explicit quantum transport as evidenced by negative differential transconductances (NDTCs) has been observed in a set of quantum well (QW) transistors fabricated using industrial silicon complementary metal-oxide-semiconductor processing. Detailed gate length and temperature dependence characteristics of the NDTCs in these devices have been measured. The QW potential was formed via lateral ion implantation doping on a commercial 45 nm technology node process line, and measurements of the transfer characteristics show NDTCs up to room temperature. Gate length dependence of NDTCs shows a correlation of the interface channel length with the number of NDTCs formed as well as with the gate voltage (VG) spacing between NDTCs. The VG spacing between multiple NDTCs suggests a quasi-parabolic QW potential profile. The temperature dependence is consistent with partial freeze-out of carrier concentration against a degenerately doped background

  16. Epidemiologia do transtorno bipolar Epidemiology of bipolar disorders

    Maurício Silva de Lima


    Full Text Available A formulação de políticas em saúde mental depende essencialmente de informações a respeito da freqüência e distribuição dos transtornos mentais. Nas últimas duas décadas, pesquisas de base populacional em epidemiologia psiquiátrica têm sido conduzidas, gerando informações detalhadas sobre freqüência, fatores de risco, incapacidade social e utilização de serviços de saúde. Neste artigo, dados sobre a epidemiologia do transtorno bipolar (TB são discutidos, a partir de resultados de recentes pesquisas populacionais: o estudo da Área de Captação Epidemiológica do Instituto Nacional de Saúde Mental dos Estados Unidos (ECA-NIMH, a Pesquisa Nacional de Comorbidade (NCS, a Pesquisa de Morbidade Psiquiátrica na Grã-Bretanha (OPCS, o Estudo Brasileiro Multicêntrico de Morbidade Psiquiátrica e os estudos longitudinais conduzidos por Angst, em Zurique. As estimativas de prevalências de transtorno bipolar são relativamente baixas, independentemente do lugar onde a pesquisa foi conduzida, do tipo de instrumento diagnóstico usado e dos períodos de tempo para os quais a prevalência se aplica. A partir da introdução do conceito de espectro bipolar, ampliando as fronteiras diagnósticas do TB, as estimativas de prevalências encontradas são substancialmente mais altas. Tais estimativas, entretanto, ainda carecem de validação em estudos populacionais. O transtorno afetivo bipolar é igualmente prevalente entre homens e mulheres, sendo mais freqüente entre solteiros ou separados. Indivíduos acometidos têm maiores taxas de desemprego e estão mais sujeitos a utilizarem serviços médicos e serem hospitalizados. O custo e a eficácia dos tratamentos do TB devem ser balanceados com o alto custo individual e social associados à enfermidade.Information about the epidemiology of bipolar disorders is essential for providing a framework for the formulation of effective mental health policy. In the last two decades, population

  17. Electronic amplifiers for automatic compensators

    Polonnikov, D Ye


    Electronic Amplifiers for Automatic Compensators presents the design and operation of electronic amplifiers for use in automatic control and measuring systems. This book is composed of eight chapters that consider the problems of constructing input and output circuits of amplifiers, suppression of interference and ensuring high sensitivity.This work begins with a survey of the operating principles of electronic amplifiers in automatic compensator systems. The succeeding chapters deal with circuit selection and the calculation and determination of the principal characteristics of amplifiers, as

  18. Simplified design of IC amplifiers

    Lenk, John


    Simplified Design of IC Amplifiers has something for everyone involved in electronics. No matter what skill level, this book shows how to design and experiment with IC amplifiers. For experimenters, students, and serious hobbyists, this book provides sufficient information to design and build IC amplifier circuits from 'scratch'. For working engineers who design amplifier circuits or select IC amplifiers, the book provides a variety of circuit configurations to make designing easier.Provides basics for all phases of practical design.Covers the most popular forms for amplif

  19. Application of Bipolar Fuzzy Sets in Graph Structures

    Muhammad Akram; Rabia Akmal


    A graph structure is a useful tool in solving the combinatorial problems in different areas of computer science and computational intelligence systems. In this paper, we apply the concept of bipolar fuzzy sets to graph structures. We introduce certain notions, including bipolar fuzzy graph structure (BFGS), strong bipolar fuzzy graph structure, bipolar fuzzy Ni-cycle, bipolar fuzzy Ni-tree, bipolar fuzzy Ni-cut vertex, and bipolar fuzzy Ni-bridge, and illustrate these notions by several examp...

  20. Sleep Disturbances in Bipolar Disorder

    Cátia Alves Moreira


    Full Text Available Background: Bipolar disorder, characterized by episodes of mania, hypomania and depression is associated with sleep disturbances and circadian rhythm disruption. These changes have significant impact on quality of life and in the disease prognosis. Aims: Review of the main sleep disturbances observed in the bipolar disorder, their clinical impact and the hypothetical pathophysiological mechanisms involved. Methods: We conducted a non-systematic review of the literature in English through research in PubMed with the keywords “sleep disturbance”, “bipolar disorder”, “polysomnography”. Results and Conclusions: Complaints about sleep pattern changes may occur during any phase of the disease. These in clude frequent night-time awakenings, poor sleep quality, reduction of the total sleeping time and decreased latency and increased density of REM sleep. The treatment of the sleep disturbances observed in bipolar disorder should be considered a priority, since it prevents symptoms recurrence and facilitate the socio-professional integration, thus providing greater success in patient’s rehabilitation and quality of life.

  1. Corrosion resistant metallic bipolar plate

    Brady, Michael P.; Schneibel, Joachim H.; Pint, Bruce A.; Maziasz, Philip J.


    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.

  2. [Cognitive deficits in bipolar disorder].

    Sachs, Gabriele; Schaffer, Markus; Winklbaur, Bernadette


    Bipolar disorders are often associated with cognitive deficits which have an influence on social functioning and the course of the illness. These deficits have an impact on occupational ability and social integration. To date, specific cognitive domains have been found which characterize bipolar affective disorders. However, there is evidence of stable and lasting cognitive impairment in all phases of the disorder, including the remission phase, in the following domains: sustained attention, memory and executive functions (e.g. cognitive flexibility and problem solving). Although their cognitive deficits are comparable the deficits in patients with schizophrenia are more severe than those with bipolar disorder. Recent brain imaging findings indicate structural and functional abnormalities in the cortical and limbic networks of the brain in patients with bipolar disorder compared to healthy controls. Mood stabilizer and atypical antipsychotics may reduce cognitive deficits in certain domains (e.g. executive functions and word fluency) and may have a positive effect on quality of life and social functioning. PMID:17640495

  3. Social support and bipolar disorder

    Paula Mendonça Studart


    Full Text Available Background Bipolar disorder is a chronic condition that affects the functioning of its carriers in many different ways, even when treated properly. Therefore, it’s also important to identify the psychosocial aspects that could contribute to an improvement of this population’s quality of life.Objective Carry out a literature review on the role of social support in cases of bipolar disorder.Method A research on the following online databases PubMed, Lilacs and SciELO was conducted by using the keywords “social support” or “social networks” and “mood disorders” or “bipolar disorder” or “affective disorder,” with no defined timeline.Results Only 13 studies concerning the topic of social support and BD were found in the search for related articles. Generally speaking, the results show low rates of social support for BD patients.Discussion Despite the growing interest in the overall functioning of patients with bipolar disorder, studies on social support are still rare. Besides, the existing studies on the subject use different methodologies, making it difficult to establish data comparisons.

  4. Building valve amplifiers

    Jones, Morgan


    Building Valve Amplifiers is a unique hands-on guide for anyone working with tube audio equipment--as an electronics hobbyist, audiophile or audio engineer. This 2nd Edition builds on the success of the first with technology and technique revisions throughout and, significantly, a major new self-build project, worked through step-by-step, which puts into practice the principles and techniques introduced throughout the book. Particular attention has been paid to answering questions commonly asked by newcomers to the world of the valve, whether audio enthusiasts tackling their first build or

  5. Wideband amplifier design

    Hollister, Allen L


    In this book, the theory needed to understand wideband amplifier design using the simplest models possible will be developed. This theory will be used to develop algebraic equations that describe particular circuits used in high frequency design so that the reader develops a ""gut level"" understanding of the process and circuit. SPICE and Genesys simulations will be performed to show the accuracy of the algebraic models. By looking at differences between the algebraic equations and the simulations, new algebraic models will be developed that include parameters originally left out of the model


    Kabell, L.J.


    Electrical circults for use in computers and the like are described. particularly a regenerative bistable transistor amplifler which is iurned on by a clock signal when an information signal permits and is turned off by the clock signal. The amplifier porforms the above function with reduced power requirements for the clock signal and circuit operation. The power requirements are reduced in one way by employing transformer coupling which increases the collector circuit efficiency by eliminating the loss of power in the collector load resistor.

  7. Quantum entanglement degrees amplifier

    Wu, Xiang-Yao; Liu, Xiao-Jing; Liang, Yu; Meng, Xiang-Dong; Li, Hong; Zhang, Si-Qi


    The quantum entangled degrees of entangled states become smaller with the transmission distance increasing, how to keep the purity of quantum entangled states is the puzzle in quantum communication. In the paper, we have designed a new type entanglement degrees amplifier by one-dimensional photonic crystal, which is similar as the relay station of classical electromagnetic communication. We find when the entangled states of two-photon and three-photon pass through photonic crystal, their entanglement degrees can be magnified, which make the entanglement states can be long range propagation and the quantum communication can be really realized.

  8. A InGaP/GaAs HBT WLAN Power Amplifier with Power Detector

    Lee, Kyung Ai; Lee, Dong Ho; Park, Hyun-Min; Cheon, Sang-Hoon; Park, Jae-Woo; Yoo, Hyung-mo; Hong, Songcheol


    A two-stage InGaP/GaAs heterojunction bipolar transistor (HBT) power amplifier is developed for WLAN 802.11b application. This is integrated with power detector that senses input power of power stage in order to decrease output power loss of detecting. The power amplifier delivers up to 26dBm output power with the maximum power-added efficiency (PAE) of 31% including consumption of the power detector under the supply voltage of 3.3V




    High-average-current linear electron accelerators require photoinjectors capable of delivering tens to hundreds of mA average current, with peak currents of hundreds of amps. Standard photocathodes face significant challenges in meeting these requirements, and often have short operational lifetimes in an accelerator environment. We report on recent progress toward development of secondary emission amplifiers for photocathodes, which are intended to increase the achievable average current while protecting the cathode from the accelerator. The amplifier is a thin diamond wafer which converts energetic (few keV) primary electrons into hundreds of electron-hole pairs via secondary electron emission. The electrons drift through the diamond under an external bias and are emitted into vacuum via a hydrogen-terminated surface with negative electron affinity (NEA). Secondary emission gain of over 200 has been achieved. Two methods of patterning diamond, laser ablation and reactive-ion etching (RIE), are being developed to produce the required geometry. A variety of diagnostic techniques, including FTIR, SEM and AFM, have been used to characterize the diamonds.

  10. Universal Signal Conditioning Amplifier

    Kinney, Frank


    The Technological Research and Development Authority (TRDA) and NASA-KSC entered into a cooperative agreement in March of 1994 to achieve the utilization and commercialization of a technology development for benefiting both the Space Program and U.S. industry on a "dual-use basis". The technology involved in this transfer is a new, unique Universal Conditioning Amplifier (USCA) used in connection with various types of transducers. The project was initiated in partnership with I-Net Corporation, Lockheed Martin Telemetry & Instrumentation (formerly Loral Test and Information Systems) and Brevard Community College. The project consists of designing, miniaturizing, manufacturing, and testing an existing prototype of USCA that was developed for NASA-KSC by the I-Net Corporation. The USCA is a rugged and field-installable self (or remotely)- programmable amplifier that works in combination with a tag random access memory (RAM) attached to various types of transducers. This summary report comprises performance evaluations, TRDA partnership tasks, a project summary, project milestones and results.

  11. Stability investigation for InP DHBT mm‐wave power amplifier

    Yan, Lei; Johansen, Tom Keinicke; Kammersgaard, Jacob


    In this article, we discuss stability issues for mm‐wave monolithic integrated power amplifiers using InP double heterojunction bipolar transistor (DHBT) technology targeting E‐band applications at 71–76 GHz and 81–86 GHz. Different stability detection methods based on the classical two‐port K‐Δs...... Periodicals, Inc. Int J RF and Microwave CAE 23: 662–674, 2013....

  12. Mood Disorders in Family Practice: Beyond Unipolarity to Bipolarity

    Manning, J. Sloan; Ahmed, Saeeduddin; McGuire, Hillary C.; Hay, Donald P.


    Primary care physicians increasingly have treated depressive disorders over the last decade. Unrecognized bipolar disorder, sometimes misdiagnosed as unipolar depression, may lead to treatment resistance or nonresponse. We describe differences between unipolar and bipolar disorders, focusing on recognition, diagnosis, and treatment of bipolar spectrum disorders such as bipolar I, bipolar II, antidepressant-induced mania, and cyclothymia. Broadening the understanding of these different disorde...

  13. Nicotine dependence and psychosis in Bipolar disorder and Schizoaffective disorder, Bipolar type.

    Estrada, Elena; Hartz, Sarah M; Tran, Jeffrey; Hilty, Donald M; Sklar, Pamela; Smoller, Jordan W; Pato, Michele T; Pato, Carlos N


    Patients with Bipolar disorder smoke more than the general population. Smoking negatively impacts mortality and clinical course in Bipolar disorder patients. Prior studies have shown contradictory results regarding the impact of psychosis on smoking behavior in Bipolar disorder. We analyzed a large sample of Bipolar disorder and Schizoaffective disorder, Bipolar Type patients and predicted those with a history of psychosis would be more likely to be nicotine dependent. Data from subjects and controls were collected from the Genomic Psychiatry Cohort (GPC). Subjects were diagnosed with Bipolar disorder without psychosis (N = 610), Bipolar disorder with psychosis (N = 1544). Participants were classified with or without nicotine dependence. Diagnostic groups were compared to controls (N = 10065) using logistic regression. Among smokers (N = 6157), those with Bipolar disorder had an increased risk of nicotine dependence (OR = 2.5; P Bipolar disorder with psychosis were more likely to be dependent than Bipolar disorder patients without psychosis (OR = 1.3; P = 0.03). Schizoaffective disorder, Bipolar Type patients had more risk of nicotine dependence when compared to Bipolar disorder patients with or without psychosis (OR = 1.2; P = 0.02). Bipolar disorder patients experiencing more severity of psychosis have more risk of nicotine dependence. © 2015 Wiley Periodicals, Inc. PMID:26467098

  14. Circadian rhythms in the neuorbiology of bipolar of bipolar disorder

    Timothy, Joseph


    Daily rhythms of physiology and behaviour in mammals are orchestrated by a hierarchical network of cellular oscillators. The master pacemaker that defines local and systemic timing across the brain and body are the suprachiasmatic nuclei of the hypothalamus (SCN). Disruption to the timing of sleep and daily behavioural activity can manifest in a range of pathologies including neuropsychiatric disorders. Bipolar disorder (BPD) is once such neurological condition that exhibits profound associat...

  15. Characterisation Of Low Noise Amplifier



    Amplification is one of the most basic and prevalent microwave circuit functions inmodern RF and microwave systems. Early microwave amplifiers relied on tubes, such asklystrons and traveling-wave tubes, or solid-state reflection amplifiers based on thenegative resistance characteristics of tunnel or varactor diodes. But due to the dramaticimprovements and innovations in solid-state technology that have occurred since the1970s, most RF and microwave amplifiers today use transistor devices such...

  16. Self-amplified CMOS image sensor using a current-mode readout circuit

    Santos, Patrick M.; de Lima Monteiro, Davies W.; Pittet, Patrick


    The feature size of the CMOS processes decreased during the past few years and problems such as reduced dynamic range have become more significant in voltage-mode pixels, even though the integration of more functionality inside the pixel has become easier. This work makes a contribution on both sides: the possibility of a high signal excursion range using current-mode circuits together with functionality addition by making signal amplification inside the pixel. The classic 3T pixel architecture was rebuild with small modifications to integrate a transconductance amplifier providing a current as an output. The matrix with these new pixels will operate as a whole large transistor outsourcing an amplified current that will be used for signal processing. This current is controlled by the intensity of the light received by the matrix, modulated pixel by pixel. The output current can be controlled by the biasing circuits to achieve a very large range of output signal levels. It can also be controlled with the matrix size and this permits a very high degree of freedom on the signal level, observing the current densities inside the integrated circuit. In addition, the matrix can operate at very small integration times. Its applications would be those in which fast imaging processing, high signal amplification are required and low resolution is not a major problem, such as UV image sensors. Simulation results will be presented to support: operation, control, design, signal excursion levels and linearity for a matrix of pixels that was conceived using this new concept of sensor.

  17. A novel low-voltage operational amplifier for low-power pipelined ADCs

    A novel low-voltage two-stage operational amplifier employing class-AB architecture is presented. The structure utilizes level-shifters and current mirrors to create the class-AB behavior in the first and second stages. With this structure, the transconductances of the two stages are double compared with the normal configuration without class-AB behaviors with the same current consumption. Thus power can be saved and the operation frequency can be increased. The nested cascode miller compensation and symmetric common-mode feedback circuits are used for large unit-gain bandwidth, good phase margin and stability. Simulation results show that the sample-and-hold of the 12-bit 40-Ms/s pipelined ADC using the proposed amplifier consumes only 5.8 mW from 1.2 V power supply with signal-to-noise-and-distortion ratio 89.5 dB, spurious-free dynamic range 95.7 dB and total harmonic distortion -94.3 dB with Nyquist input signal frequency.

  18. Silicon on insulator bipolar junction transistors for flexible microwave applications

    Bavier, John McGoldrick

    Microwave frequency flexible electronic devices require a high quality semiconducting material and a set of fabrication techniques that are compatible with device integration onto flexible polymer substrates. Over the past ten years, monocrystalline silicon nanomembranes (SiNMs) have been studied as a flexible semiconducting material that is compatible with industrial Si processing. Fabricated from commercial silicon on insulator (SOI) wafers, SiNMs can be transferred to flexible substrates using a variety of techniques. Due to their high carrier mobilities, SiNMs are a promising candidate for flexible microwave frequency devices. This dissertation presents fabrication techniques for flexible SiNM devices in general, as well as the progress made towards the development of a microwave frequency SiNM bipolar junction transistor (BJT). In order to overcome previous limitations associated with adhesion, novel methods for transfer printing of metal films and SiNMs are presented. These techniques enable transfer printing of a range of metal films and improve the alignment of small transfer printed SiNM devices. Work towards the development of a microwave frequency BJT on SOI for SiNM devices is also described. Utilizing a self-aligned polysilicon sidewall spacer technique, a BJT with an ultra-narrow base region is fabricated and tested. Two regimes of operation are identified and characterized under DC conditions. At low base currents, devices exhibited forward current gain as high as betaF = 900. At higher base current values, a transconductance of 59 mS was observed. Microwave scattering parameters were obtained for the BJTs under both biasing conditions and compared to unbiased measurements. Microwave frequency gain was not observed. Instead, bias-dependent non-reciprocal behavior was observed and examined. Limitations associated with the microwave impedance-matched electrode configuration are presented. High current densities in the narrow electrodes cause localized

  19. Modeling of semiconductor optical amplifiers

    Mørk, Jesper; Bischoff, Svend; Berg, Tommy Winther;

    We discuss the modelling of semiconductor optical amplifiers with emphasis on their high-speed properties. Applications in linear amplification as well as ultrafast optical signal processing are reviewed. Finally, the possible role of quantum-dot based optical amplifiers is discussed.......We discuss the modelling of semiconductor optical amplifiers with emphasis on their high-speed properties. Applications in linear amplification as well as ultrafast optical signal processing are reviewed. Finally, the possible role of quantum-dot based optical amplifiers is discussed....

  20. Amplified leak detection

    Mahony, James


    Leaks are one of the major concerns for oil and gas producers. But recently, a Calgary-based company developed a tool that can find natural gas leaks in wellbores. This has relieved the oil and gas producers because the optics of finding downhole leaks just got a little brighter. Since then, there have been continuous efforts to broaden and refine fiber optics based methods. This paper presents amplified leak detection using fiber optics to identify even the smallest liquid leaks downhole. At high volumes, detection of downhole leaks in liquids is not a problem but at lower flow rates, the leaks become harder to detect, and at very low flow rates, they might not be detected at all. Hifi Engineering Inc. has developed the LeakSonar fiber optic acoustic sensor array that is specifically designed to detect and locate fluid migration in wellbores, even through multiple strings of casing.

  1. Metatronic transistor amplifier

    Chettiar, Uday K.; Engheta, Nader


    Utilizing the notion of metamaterials, in recent years the concept of a circuit and lumped circuit elements have been extended to the optical domains, providing the paradigm of optical metatronics, i.e., metamaterial-inspired optical nanocircuitry, as a powerful tool for design and study of more complex systems at the nanoscale. In this paper we present a design for a new metatronic element, namely, a metatronic transistor that functions as an amplifier. As shown by our analytical and numerical paper here, this metatronic transistor provides gain as well as isolation between the input and output ports of such two-port device. The cascadability and fan-out aspects of this element are also explored.

  2. Direct coupled amplifiers using field effect transistors

    The concept of the uni-polar field effect transistor (P.E.T.) was known before the invention of the bi-polar transistor but it is only recently that they have been made commercially. Being produced as yet only in small quantities, their price imposes a restriction on use to circuits where their peculiar properties can be exploited to the full. One such application is described here where the combination of low voltage drift and relatively low input leakage current are necessarily used together. One of the instruments used to control nuclear reactors has a logarithmic response to the mean output current from a polarised ionisation chamber. The logarithmic signal is then differentiated electrically, the result being displayed on a meter calibrated to show the reactor divergence or doubling time. If displayed in doubling time the scale is calibrated reciprocally. Because of the wide range obtained in the logarithmic section and the limited supply voltage, an output of 1 volt per decade change in ionisation current is used. Differentiating this gives a current of 1.5 x 10-8 A for p.s.D. (20 sec. doubling time) in the differentiating amplifier. To overcome some of the problems of noise due to statistical variations in input current, the circuit design necessitates a resistive path to ground at the amplifier input of 20 M.ohms. A schematic diagram is shown. 1. It is evident that a zero drift of 1% can be caused by a leakage current of 1.5 x 10-10 A or an offset voltage of 3 mV at the amplifier input. Although the presently used electrometer valve is satisfactory from the point of view of grid current, there have been sudden changes in grid to grid voltage (the valve is a double triode) of up to 10 m.V. It has been found that a pair of F.E.T's. can be used to replace the electrometer valve so long as care is taken in correct balance of the two devices. An investigation has been made into the characteristics of some fourteen devices to see whether those with very different

  3. [Psychopharmacological treatment of bipolar disease].

    Licht, Rasmus W; Vestergaard, Per


    This paper gives an update on the psychopharmacological treatment of bipolar disorder. The antimanic efficacy of lithium is well documented. The same applies to valproate, which is also efficacious in mixed mania. Conventional antipsychotics act fast in mania and do not require blood tests, but they have considerable neurological side effects. The newer antipsychotics, olanzapine, risperidone, and ziprasidone, have also been shown to have antimanic efficacy. Clozapine is extremely effective, also when other treatment fails. For the treatment of bipolar depression, lithium, lamotrigine, and antidepressants all seem to work, but antidepressants may sometimes precipitate mania or worsen the course of illness. For prophylaxis, lithium is still to be considered the first drug of choice. However, for several reasons, for instance treatment failure or side effects, long-term treatment with antiepileptics may often be necessary. Among the antiepileptics, carbamazepine, valproate, and lamotrigine are the best studied. PMID:12025705

  4. Unsplit bipolar pulse forming line

    Rhodes, Mark A.


    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.

  5. Prepubertal bipolar disorder: available pharmacological treatment options.

    Masi, Gabriele


    Awareness of bipolar spectrum disorders in children is rapidly increasing, with a more precise definition of their clinical subtypes and early signs. Paediatric bipolar disorder can lead to an important impairment in scholastic, familial and social functioning, and to a higher risk for substance abuse and suicide. In the context of a multimodal approach, the core treatment of early-onset bipolar disorder is pharmacological. This review focuses on the empirical evidence for pharmacotherapy in paediatric bipolar disorder. Mood stabilizers, including lithium, and older and newer anticonvulsivants will be considered, in mono- or polypharmacy. Atypical antipsychotics will be considered in more severe and/or treatment-resistant manic or mixed episodes. Finally, the prophylaxis of intercritical phases and the management of specific challenging conditions, such as bipolar depression and attention deficit hyperactivity disorder, with bipolar comorbidity, will be reviewed. PMID:15934881

  6. Neurocognitive function in bipolar disorder: a comparison between bipolar I and II disorder and matched controls

    Pålsson, Erik; Figueras, Clara; Johansson, Anette GM; Ekman, Carl-Johan; Hultman, Björn; Östlind, Josefin; Landén, Mikael


    Background Cognitive deficits have been documented in patients with bipolar disorder. Further, it has been suggested that the degree and type of cognitive impairment differ between bipolar I and bipolar II disorder, but data is conflicting and remains inconclusive. This study aimed to clarify the suggested differences in cognitive impairment between patients with bipolar I and II disorder in a relatively large, clinically stable sample while controlling for potential confounders. Methods 67 p...

  7. Bipolar disorder: staging and neuroprogression

    Rodrigues, Aline André; Rosa, Adriana R.; Kunz, Maurício; Ascoli, Bruna; Kapczinski, Flávio


    In bipolar disorder illness progression has been associated with a higher number of mood episodes and hospitalizations, poorer response to treatment, and more severe cognitive and functional impairment. This supports the notion of the use of staging models in this illness. The value of staging models has long been recognized in many medical and malignant conditions. Staging models rely on the fact that different interventions may suit different stages of the disorder, and that better outcomes...

  8. Major Ups and Downs: Bipolar Disorder Brings Extreme Mood Swings

    ... our exit disclaimer . Subscribe Major Ups and Downs Bipolar Disorder Brings Extreme Mood Swings Most people feel happy ... Strike Out Stroke Wise Choices Links Dealing with Bipolar Disorder If you have bipolar disorder, get treatment and ...

  9. Cognitive Behavioral Therapy in Bipolar Disorder

    Zeynep Mackali; Ahmet Tosun


    Bipolar disorder is an early-onset, chronic disorder. It impairs occupational, social, and family functioning, which makes learning to adapt living with the disorder and its treatment critically important. Therefore, it has now become common knowledge that psychosocial interventions are also necessary in the treatment of bipolar disorder adjunctive to pharmacotherapy. Thus, whichever psychosocial interventions are more effective in bipolar disorder is a crucial research question. In this arti...

  10. Adolescent Bipolar Disorder: A Clinical Vignette

    Rodgers, Melissa J.; Zylstra, Robert G.; McKay, Julia B.; Solomon, A. Lee; Choby, Beth A.


    Adolescence is a vulnerable developmental phase marked by physical, psychological, and social changes that rapidly expose young people to a wide range of new stressors. When differentiating between bipolar disorder and teenage “acting out,” a careful history is important. Adolescent bipolar disorder is a psychiatric illness characterized by fluctuating episodes of mood elevation and depression that is frequently neither recognized nor formally diagnosed. Adolescents with bipolar disorder ofte...

  11. Risperidone in the treatment of bipolar mania

    Sajatovic, Martha; Subramoniam, Madhusoodanan; Fuller, Matthew A


    Atypical antipsychotic medications have assumed growing importance for the treatment of bipolar disorder, an illness that affects approximately 1.2%–3.7% of the general population in a given year. Current practice guidelines for the treatment of bipolar mania support the use of atypical antipsychotic medications as monotherapy or as a component of polytherapy, and in clinical settings the use of atypical antipsychotics to treat bipolar disorder is widespread. Risperidone is an atypical antips...

  12. Biological rhythm disturbance in remitted bipolar patients

    Rosa, Adriane R; Comes, Mercè; Torrent, Carla; Solè, Brisa; Reinares, Maria; Pachiarotti, Isabella; Salamero, Manel; Kapczinski, Flávio; Colom, Francesc; Vieta, Eduard


    Background Biological rhythm disturbance is common in bipolar patients and seems to affect the course and prognosis of the illness negatively. The main aim of the current study was to assess biological rhythms in remitted bipolar patients. We also assessed whether there was an association between clinical variables or functioning and biological rhythms in remitted bipolar participants. Methods The Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) was used to assess biologi...

  13. Bipolar Experiences and Self-Identity

    Bedford, Rosie


    Background: Bipolar II disorder has a prevalence rate of approximately 0.4% in adults and 1.5% in adolescents, with the onset typically around 18 years old (Merikangas & Lamers, 2012). As the age of onset is during adolescent years the impact on identity is of special interest. Although the profound impact bipolar has on an individual’s sense of self has surfaced as a predominant theme in the bipolar literature, there remains a dearth of research directly addressing this impact. ...

  14. Pharmaceutical treatment of acute bipolar depression

    Fountoulakis, Konstantinos N


    The treatment of bipolar depression is one of the most challenging fields in contemporary psychiatry. The best data concern the antipsychotics quetiapine and the olanzapine-fluoxetine combination. However, the usefulness of antidepressants in bipolar depression remains controversial; positive data are available for fluoxetine but negative results have been published for paroxetine. Accumulated knowledge so far suggests that bipolar patients need continuous administration of an antimanic agent...

  15. Distinctions between bipolar and unipolar depression

    Cuellar, Amy K.; Johnson, Sheri L.; Winters, Ray


    This is a review of the studies comparing unipolar and bipolar depression, with focus on the course, symptomatology, neurobiology, and psychosocial literatures. These are reviewed with one question in mind: does the evidence support diagnosing bipolar and unipolar depressions as the same disorder or different? The current nomenclature of bipolar and unipolar disorders has resulted in research that compares these disorders as a whole, without considering depression separately from mania within...

  16. The common bipolar phenotype in young people

    Rock, Philippa L; Chandler, Rebecca A.; Harmer, Catherine J.; Rogers, Robert D.; Goodwin, Guy M.


    Background Mood elevation is common in adolescents and young adults. The aim of this study was to investigate the prevalence of a bipolar diagnosis and co-morbidity in individuals identified by online screening for experience of (hypo)manic symptoms in order to better define the common bipolar phenotype in young people. Methods Survey data regarding experience of (hypo)manic symptoms and occurrence of co-morbidities were analysed for 106 students satisfying criteria for probable bipolar syndr...

  17. Course of Subthreshold Bipolar Disorder in Youth: Diagnostic Progression from Bipolar Disorder Not Otherwise Specified

    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.


    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…

  18. Bipolar Disorder and Obsessive Compulsive Disorder Comorbidity

    Necla Keskin


    Full Text Available The comorbidity of bipolar disorder and anxiety disorders is a well known concept. Obsessive-compulsive disorder is the most commonly seen comorbid anxiety disorder in bipolar patients. Some genetic variants, neurotransmitters especially serotonergic systems and second-messenger systems are thought to be responsible for its etiology. Bipolar disorder alters the clinical aspects of obsessive compulsive disorder and is associated with poorer outcome. The determination of comorbidity between bipolar disorder and obsessive compulsive disorder is quite important for appropriate clinical management and treatment. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 429-437

  19. Semiconductor DC amplifier AEP 1487

    A semiconductor dc amplifier has been designed with the object of achieving low drift without component selection or special temperature-balancing adjustments. Modulator and ac-amplifier techniques have been adopted in order to avoid the drifts that occur when transistors are directly coupled. The diode-ring modulator described in CREL-902 has been used as the input chopper. (author)

  20. Poorer sustained attention in bipolar I than bipolar II disorder

    Chen Shih-Heng


    Full Text Available Abstract Background Nearly all information processing during cognitive processing takes place during periods of sustained attention. Sustained attention deficit is among the most commonly reported impairments in bipolar disorder (BP. The majority of previous studies have only focused on bipolar I disorder (BP I, owing to underdiagnosis or misdiagnosis of bipolar II disorder (BP II. With the refinement of the bipolar spectrum paradigm, the goal of this study was to compare the sustained attention of interepisode patients with BP I to those with BP II. Methods In all, 51 interepisode BP patients (22 with BP I and 29 with BP II and 20 healthy controls participated in this study. The severity of psychiatric symptoms was assessed by the 17-item Hamilton Depression Rating Scale and the Young Mania Rating Scale. All participants undertook Conners' Continuous Performance Test II (CPT-II to evaluate sustained attention. Results After controlling for the severity of symptoms, age and years of education, BP I patients had a significantly longer reaction times (F(2,68 = 7.648, P = 0.001, worse detectability (d' values (F(2,68 = 6.313, P = 0.003 and more commission errors (F(2,68 = 6.182, P = 0.004 than BP II patients and healthy controls. BP II patients and controls scored significantly higher than BP I patients for d' (F = 6.313, P = 0.003. No significant difference was found among the three groups in omission errors and no significant correlations were observed between CPT-II performance and clinical characteristics in the three groups. Conclusions These findings suggested that impairments in sustained attention might be more representative of BP I than BP II after controlling for the severity of symptoms, age, years of education and reaction time on the attentional test. A longitudinal follow-up study design with a larger sample size might be needed to provide more information on chronological sustained attention deficit in BP patients, and to illustrate

  1. Progression along the Bipolar Spectrum: A Longitudinal Study of Predictors of Conversion from Bipolar Spectrum Conditions to Bipolar I and II Disorders

    Alloy, Lauren B.; Urošević, Snežana; Abramson, Lyn Y.; Jager-Hyman, Shari; Nusslock, Robin; Whitehouse, Wayne G.; Hogan, Michael


    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)...

  2. Developmental staging models in bipolar disorder

    Passos, Ives C; Jansen, Karen; Kapczinski, Flavio


    The previous contribution of Duffy and colleagues suggests that a chain of behavioral events starting during childhood precedes the development of full-blown bipolar disorder. In this vein, the recent contribution of Keown-Stoneman and colleagues brings a new perspective to the study of prodromal symptoms of bipolar disorder.

  3. Modeling "Soft" Errors in Bipolar Integrated Circuits

    Zoutendyk, J.; Benumof, R.; Vonroos, O.


    Mathematical models represent single-event upset in bipolar memory chips. Physics of single-event upset in integrated circuits discussed in theoretical paper. Pair of companion reports present mathematical models to predict critical charges for producing single-event upset in bipolar randomaccess memory (RAM) chips.

  4. Bipolar Disorder and Cognitive Therapy: A Commentary

    Riskind, John H.


    This article comments on the three articles (Leahy, 2005; Newman, 2005; and Reilly-Harrington & Knauz, 2005) that deal with the applications of cognitive therapy to treatment of bipolar disorder. They focus on the uses of cognitive therapy in treating three important facets of the special problems of bipolar patients: rapid cycling, severe…

  5. Bipolar states of electrons in clusters

    Conditions are found under which the production of a bipolar state in a cluster consisting of polar molecules is possible. In (H2O)n cluster the bipolar state is possible under n ≥ 630, and in (NH3)n one - under n ≥ 2015. 4 refs

  6. Swimming in Deep Water: Childhood Bipolar Disorder

    Senokossoff, Gwyn W.; Stoddard, Kim


    The authors focused on one parent's struggles in finding a diagnosis and intervention for a child who had bipolar disorder. The authors explain the process of identification, diagnosis, and intervention of a child who had bipolar disorder. In addition to the personal story, the authors provide information on the disorder and outline strategies…

  7. Bipolar disorder diagnosis: challenges and future directions.

    Phillips, Mary L; Kupfer, David J


    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

  8. Thomson semiconductors bipolar IC strategy to 1986

    Dellamussia, J. P.


    The strategy to develop and market bipolar integrated circuits through 1986 by thomson semiconductors is discussed. Current technology and future research on prototype microprocessors using bipolar integrated circuits is evaluated. The physical properties of the circuits such as heat dissipation, energy consumption rates and response times are studied.

  9. Bipolar Disorder in School-Age Children

    Olson, Patricia M.; Pacheco, Mary Rae


    This article examines the individual components of bipolar disorder in children and the behaviors that can escalate as a result of misdiagnosis and treatment. The brain/behavior relationship in bipolar disorders can be affected by genetics, developmental failure, or environmental influences, which can cause an onset of dramatic mood swings and…

  10. White matter microstructure alterations in bipolar disorder

    Bellani, M; Perlini, C.; Ferro, A.; Cerruti, S.; G. Rambaldelli; Isola, M.; CERINI, R.; N. Dusi; N. Andreone; Balestrieri, M.; R. Pozzi Mucelli; Tansella, M; Brambilla, P


    Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls.

  11. Small signal microwave amplifier design

    Grosch, Theodore


    This book explains techniques and examples for designing stable amplifiers for high-frequency applications in which the signal is small and the amplifier circuit is linear. An in-depth discussion of linear network theory provides the foundation needed to develop actual designs. Examples throughout the book will show you how to apply the knowledge gained in each chapter leading to the complex design of low noise amplifiers. Many exercises at the end of each chapter will help students to practice their skills. The solutions to these design problems are available in an accompanying solutions book

  12. International Standardization Activities for Optical Amplifiers

    Haruo Okamura


    International standardization activities for Optical Amplifiers at IECTC86 and ITU-T SG15 are reviewed. Current discussions include Optical Amplifier safety guideline, Reliability standard, Rest methods of Noise and PMD, Definitions of Raman amplifier parameters and OA classification.

  13. A post-SQUID ac amplifier aimed for multiplexed detector readouts

    We have built a room temperature amplifier based on Si JFETs (junction field effect transistors) intended for ac-coupled SQUID (superconducting quantum interference device) readouts, such as in frequency-domain multiplexed transition-edge sensor systems. The amplifier operates at 5 MHz centre frequency where it has the measured noise temperature of 27 K for a 60 Ω load, which includes the noise from the active termination and the room temperature transformer. When it was driven from a SQUID with an on-chip matching transformer, flux noise of 0.45 μΦ0 Hz-1/2 was obtained. Additionally, we consider the potential of the recently introduced SiGe bipolar transistors for the same application. The dynamic range considerations for SQUID multiplexers, which require the use of an amplifier with a low noise temperature, are briefly discussed

  14. Management of Bipolar II Disorder

    Michael M.C Wong


    Bipolar II disorder (BP II) disorder was recognized as a distinct subtype in the DSM-IV classification. DSM-IV criteria for BP II require the presence or history of one or more major depressive episode, plus at least one hypomanic episode, which, by definition, must last for at least 4 days. Various studies found distinct patterns of symptoms and familial inheritance for BP II disorder. BP II is commonly underdiagnosed or misdiagnosed. Making an early and accurate diagnosis of BP II is utmost...

  15. Bipolar Ag-Zn battery

    Giltner, L. John


    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

  16. Thyroid Functions and Bipolar Affective Disorder

    Subho Chakrabarti


    Full Text Available Accumulating evidence suggests that hypothalamo-pituitary-thyroid (HPT axis dysfunction is relevant to the pathophysiology and clinical course of bipolar affective disorder. Hypothyroidism, either overt or more commonly subclinical, appears to the commonest abnormality found in bipolar disorder. The prevalence of thyroid dysfunction is also likely to be greater among patients with rapid cycling and other refractory forms of the disorder. Lithium-treatment has potent antithyroid effects and can induce hypothyroidism or exacerbate a preexisting hypothyroid state. Even minor perturbations of the HPT axis may affect the outcome of bipolar disorder, necessitating careful monitoring of thyroid functions of patients on treatment. Supplementation with high dose thyroxine can be considered in some patients with treatment-refractory bipolar disorder. Neurotransmitter, neuroimaging, and genetic studies have begun to provide clues, which could lead to an improved understanding of the thyroid-bipolar disorder connection, and more optimal ways of managing this potentially disabling condition.

  17. Diagnostic stability in pediatric bipolar disorder

    Vedel Kessing, Lars; Vradi, Eleni; Andersen, Per Kragh


    BACKGROUND: The diagnostic stability of pediatric bipolar disorder has not been investigated previously. The aim was to investigate the diagnostic stability of the ICD-10 diagnosis of pediatric mania/bipolar disorder.METHODS: All patients below 19 years of age who got a diagnosis of mania....../bipolar disorder at least once in a period from 1994 to 2012 at psychiatric inpatient or outpatient contact in Denmark were identified in a nationwide register.RESULTS: Totally, 354 children and adolescents got a diagnosis of mania/bipolar disorder at least once; a minority, 144 patients (40.7%) got the diagnosis...... at the first contact whereas the remaining patients (210; 59.3%) got the diagnosis at later contacts before age 19. For the latter patients, the median time elapsed from first treatment contact with the psychiatric service system to the first diagnosis with a manic episode/bipolar disorder was nearly...

  18. A Transformer Class E Amplifier

    Mikolajewski Miroslaw


    Full Text Available In a high-efficiency Class E ZVS resonant amplifier a matching and isolation transformer can replace some or even all inductive components of the amplifier thus simplifying the circuit and reducing its cost. In the paper a theoretical analysis, a design example and its experimental verification for a transformer Class E amplifier are presented. In the experimental amplifier with a transformer as the only inductive component in the circuit high efficiency ηMAX = 0.95 was achieved for supply voltage VI = 36 V, maximum output power POMAX = 100 W and the switching frequency f = 300 kHz. Measured parameters and waveforms showed a good agreement with theoretical predictions. Moreover, the relative bandwidth of the switching frequency was only 19% to obtain output power control from 4.8 W to POMAX with efficiency not less than 0.9 in the regulation range.

  19. TARC: Carlo Rubbia's Energy Amplifier

    Laurent Guiraud


    Transmutation by Adiabatic Resonance Crossing (TARC) is Carlo Rubbia's energy amplifier. This CERN experiment demonstrated that long-lived fission fragments, such as 99-TC, can be efficiently destroyed.

  20. New Packaging for Amplifier Slabs

    Riley, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thorsness, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Suratwala, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Steele, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rogowski, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    The following memo provides a discussion and detailed procedure for a new finished amplifier slab shipping and storage container. The new package is designed to maintain an environment of <5% RH to minimize weathering.

  1. Transistor oscillator and amplifier grids

    Weikle, Robert M., II; Kim, Moonil; Hacker, Jonathan B.; De Lisio, Michael P.; Popvić, Zoya B.; Rutledge, David B.


    Although quasi-optical techniques are applicable to a large variety of solid-state devices, special attention is given to transistors, which are attractive because they can be used as either amplifiers or oscillators. Experimental results for MESFET bar-grid and planar grid oscillators are presented. A MESFET grid amplifier that receives only vertically polarized waves at the input and radiates horizontally polarized waves at the output is discussed. These planar grids can be scaled for opera...




    Chaotic characteristics in the iteration of logistic map (one-dimensional discrete dynamic system) are simulatedand analyzed. The circuit implementation of a kind of chaotic amplifier model is based on the chaotic characteristicsthat chaos is sensitively dependent on its initial conditions, and the circuit simulation result is given using simulationprogram with integrated circuit emphasis for personal computer (PSPICE), and is compared with linear amplifier.Advantages and disadvantages of such a model are indicated.

  3. Casimir force on amplifying bodies

    Sambale, Agnes; Welsch, Dirk-Gunnar; Buhmann, Stefan Yoshi; Dung, Ho Trung


    Based on a unified approach to macroscopic QED that allows for the inclusion of amplification in a limited space and frequency range, we study the Casimir force as a Lorentz force on an arbitrary partially amplifying system of linearly locally responding (isotropic) magnetoelectric bodies. We demonstrate that the force on a weakly polarisable/magnetisable amplifying object in the presence of a purely absorbing environment can be expressed as a sum over the Casimir--Polder forces on the excite...

  4. Total Dose Effects on Single Event Transients in Linear Bipolar Systems

    Buchner, Stephen; McMorrow, Dale; Bernard, Muriel; Roche, Nicholas; Dusseau, Laurent


    Single Event Transients (SETs) originating in linear bipolar integrated circuits are known to undermine the reliability of electronic systems operating in the radiation environment of space. Ionizing particle radiation produces a variety of SETs in linear bipolar circuits. The extent to which these SETs threaten system reliability depends on both their shapes (amplitude and width) and their threshold energies. In general, SETs with large amplitudes and widths are the most likely to propagate from a bipolar circuit's output through a subsystem. The danger these SET pose is that, if they become latched in a follow-on circuit, they could cause an erroneous system response. Long-term exposure of linear bipolar circuits to particle radiation produces total ionizing dose (TID) and/or displacement damage dose (DDD) effects that are characterized by a gradual degradation in some of the circuit's electrical parameters. For example, an operational amplifier's gain-bandwidth product is reduced by exposure to ionizing radiation, and it is this reduction that contributes to the distortion of the SET shapes. In this paper, we compare SETs produced in a pristine LM124 operational amplifier with those produced in one exposed to ionizing radiation for three different operating configurations - voltage follower (VF), inverter with gain (IWG), and non-inverter with gain (NIWG). Each configuration produces a unique set of transient shapes that change following exposure to ionizing radiation. An important finding is that the changes depend on operating configuration; some SETs decrease in amplitude, some remain relatively unchanged, some become narrower and some become broader.

  5. Valproate, bipolar disorder and polycystic ovarian syndrome

    Okanović Milana


    Full Text Available Introduction. Polycystic ovarian syndrome is a syndrome of ovarian dysfunction with the principal features of hyperandrogenism and polycystic ovary morphology. A large number of studies conducted on this topic have suggested a possible role of anticonvulsants, particularly valproate, in the pathogenesis or risk factors associated with polycystic ovarian syndrome. Bipolar treatment guidelines from Canada and the United States of America recommend valproate as the first line strategy in the acute treatment of bipolar disorder. Discussion. Most persons with bipolar disorder require maintenance treatment. Long-term administration of valproate in women with bipolar disorder or epilepsy is believed to result in the increased risk of hyperandro­genism, menstrual abnormalities and polycystic ovaries. Valproate may also increase the risk of infertility and other associated symptoms of polycystic ovarian syndrome. Therefore, particular caution is indicated in the use of valproate in women of reproductive age. Conclusion. The treatment of the female patients with bipolar disorder presents various challenges for the clinician. Every woman of reproductive age needs to know the risk and benefits of her pharmacologic treatment options. Bipolar disorder should be considered chronic disorder, whose development is largely affected by hormonal changes and reproductive cycle in women. These issues should be researched more thoroughly in order to opt for the most appropriate treatment in women with bipolar disorder.

  6. Brief Report: A Family Risk Study Exploring Bipolar Spectrum Problems and Cognitive Biases in Adolescent Children of Bipolar Parents

    Espie, Jonathan; Jones, Steven H.; Vance, Yvonne H.; Tai, Sara J.


    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…

  7. Lower switch rate in depressed patients with bipolar II than bipolar I disorder treated adjunctively with second-generation antidepressants

    Altshuler, LL; Suppes, T; Nolen, WA; Leverich, G; Keck, PE; Frye, MA; Kupka, R; McElroy, SL; Grunze, H; Kitchen, CMR; Post, R; Black, D.O.


    Objectives: The authors compared the switch rate into hypomania/mania in depressed patients treated with second-generation antidepressants who had either bipolar I or bipolar II disorder. Method: In a 10-week trial, 184 outpatients with bipolar depression (134 with bipolar I disorder, 48 with bipola

  8. Paired structures and bipolar knowledge representation

    Montero, Javier; Bustince, Humberto; Franco, Camilo;

    In this strictly positional paper we propose a general approach to bipolar knowledge representation, where the meaning of concepts can be modelled by examining their decomposition into opposite and neutral categories. In particular, it is the semantic relationship between the opposite categories...... at the same time the type of neutrality rising in between opposites. Based on this first level of bipolar knowledge representation, paired structures in fact offer the means to characterize a specific bipolar valuation scale depending on the meaning of the concept that has to be verified. In this...

  9. Vacuum interface flashover with bipolar electric fields

    High energy, compact, particle accelerators require accelerating cavities that have large gradients and operate with high efficiency. The bipolar electric fields necessary in these efficient accelerating cavities place severe requirements on the insulator-vacuum interface. A new interface has been designed and 50 gv/cm bipolar flashover field achieved for a waveform train that lasted 1 μs. This paper discusses the design of this vacuum interface and the evaluation of various materials that led to achieving bipolar flashover fields 50% greater than the authors had previously obtained

  10. Ionizing radiations simulation on bipolar components

    This thesis presents the ionizing radiation effects on bipolar components and more specially their behavior facing the total dose. The first part is devoted to the radiation environments with a special attention to the spatial environments and new emergent environments. The specificities of bipolar components are then presented and their behavior facing the interactions. The physical mechanisms bound to the dose rate are also discussed. The second part presents a physical analysis of degradations induced by the cumulated dosimetry on bipolar components and simulation with the ATLAS code. The third part exposes an electric empirical simulation induced by the cumulated dose in static conditions. (A.L.B.)

  11. Low-Noise Band-Pass Amplifier

    Kleinberg, L.


    Circuit uses standard components to overcome common limitation of JFET amplifiers. Low-noise band-pass amplifier employs JFET and operational amplifier. High gain and band-pass characteristics are achieved with suitable choice of resistances and capacitances. Circuit should find use as low-noise amplifier, for example as first stage instrumentation systems.

  12. EMI-resilient amplifier circuits

    van der Horst, Marcel J; Linnenbank, André C


    This book enables circuit designers to reduce the errors introduced by the fundamental limitations and electromagnetic interference (EMI) in negative-feedback amplifiers.  The authors describe a systematic design approach for application specific negative-feedback amplifiers, with specified signal-to-error ratio (SER).  This approach enables designers to calculate noise, bandwidth, EMI, and the required bias parameters of the transistors used in  application specific amplifiers in order to meet the SER requirements.   ·         Describes design methods that incorporate electromagnetic interference (EMI) in the design of application specific negative-feedback amplifiers; ·         Provides designers with a structured methodology to avoid the use of trial and error in meeting signal-to-error ratio (SER) requirements; ·         Equips designers to increase EMI immunity of the amplifier itself, thus avoiding filtering at the input, reducing the number of components and avoiding detr...

  13. Spectroscopic amplifier for pin diode

    The photodiode remains the basic choice for the photo-detection and is widely used in optical communications, medical diagnostics and field of corpuscular radiation. In detecting radiation it has been used for monitoring radon and its progeny and inexpensive spectrometric systems. The development of a spectroscopic amplifier for Pin diode is presented which has the following characteristics: canceler Pole-Zero (P/Z) with a time constant of 8 μs; constant gain of 57, suitable for the acquisition system; 4th integrator Gaussian order to waveform change of exponential input to semi-Gaussian output and finally a stage of baseline restorer which prevents Dc signal contribution to the next stage. The operational amplifier used is the TLE2074 of BiFET technology of Texas Instruments with 10 MHz bandwidth, 25 V/μs of slew rate and a noise floor of 17 nv/(Hz)1/2. The integrated circuit has 4 operational amplifiers and in is contained the total of spectroscopic amplifier that is the goal of electronic design. The results show like the exponential input signal is converted to semi-Gaussian, modifying only the amplitude according to the specifications in the design. The total system is formed by the detector, which is the Pin diode, a sensitive preamplifier to the load, the spectroscopic amplifier that is what is presented and finally a pulse height analyzer (Mca) which is where the spectrum is shown. (Author)

  14. An analog bipolar-JFET master slice array for front-end electronics design

    An analog bipolar-JFET Master Slice Array (MSA) has been designed for implementation of ICs used in nuclear physics front-end electronics. The universal conception of MSAs active and passive elements provides great functional complexity to ICs in using them. The quality of active element parameters, number and values of available resistors and capacitors made it possible to integrate a four channel amplifier-shaper-discriminator with a base line restorer into the MSA die with dimensions 2.7 mmx3.6 mm. Eight-channel ICs can be made by connection of two chips by metal wiring on a wafer

  15. Antidepressant chronotherapeutics for bipolar depression.

    Benedetti, Francesco


    Chronotherapeutics refers to treatments based on the principles of circadian rhythm organization and sleep physiology, which control the exposure to environmental stimuli that act on biological rhythms, in order to achieve therapeutic effects in the treatment of psychiatric conditions. It includes manipulations of the sleep-wake cycle such as sleep deprivation and sleep phase advance, and controlled exposure to light and dark. The antidepressant effects of chronotherapeutics are evident in difficult-to-treat conditions such as bipolar depression, which has been associated with extremely low success rates of antidepressant drugs in naturalistic settings and with stable antidepressant response to chronotherapeutics in more than half of the patients. Recent advances in the study of the effects of chronotherapeutics on neurotransmitter systems, and on the biological clock machinery, allow us to pinpoint its mechanism of action and to transform it from a neglected or "orphan" treatment to a powerful clinical instrument in everyday psychiatric practice. PMID:23393416

  16. Bipolar disorder and neurophysiologic mechanisms

    Simon M McCrea


    Full Text Available Simon M McCreaDepartments of Neurology and Neuroophthalmology, University of British Columbia, 2550 Willow Street, Vancouver, British Columbia, Canada V5Z 3N9Abstract: Recent studies have suggested that some variants of bipolar disorder (BD may be due to hyperconnectivity between orbitofrontal (OFC and temporal pole (TP structures in the dominant hemisphere. Some initial MRI studies noticed that there were corpus callosum abnormalities within specific regional areas and it was hypothesized that developmentally this could result in functional or effective connectivity changes within the orbitofrontal-basal ganglia-thalamocortical circuits. Recent diffusion tensor imaging (DTI white matter fiber tractography studies may well be superior to region of interest (ROI DTI in understanding BD. A “ventral semantic stream” has been discovered connecting the TP and OFC through the uncinate and inferior longitudinal fasciculi and the elusive TP is known to be involved in theory of mind and complex narrative understanding tasks. The OFC is involved in abstract valuation in goal and sub-goal structures and the TP may be critical in binding semantic memory with person–emotion linkages associated with narrative. BD patients have relative attenuation of performance on visuoconstructional praxis consistent with an atypical localization of cognitive functions. Multiple lines of evidence suggest that some BD alleles are being selected for which could explain the enhanced creativity in higher-ability probands. Associations between ROI’s that are not normally connected could explain the higher incidence of artistic aptitude, writing ability, and scientific achievements among some mood disorder subjects.Keywords: bipolar disorder, diffusion tensor imaging, white matter tractography, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, mood dysphoria, creativity, ventral semantic stream, writing ability, artistic aptitude

  17. High-gain, high-bandwidth, rail-to-rail, constant-gm CMOS operational amplifier

    Huang, Hong-Yi; Wang, Bo-Ruei


    This study presents a high-gain, high-bandwidth, constant-gm , rail-to-rail operational amplifier (op-amp). The constant transconductance is improved with a source-to-bulk bias control of an input pair. A source degeneration scheme is also adapted to the output stage for receiving wide input range without degradation of the gain. Additionally, several compensation schemes are employed to enhance the stability. A test chip is fabricated in a 0.18 µm complementary metal-oxide semiconductor process. The active area of the op-amp is 181 × 173 µm2 and it consumes a power of 2.41 mW at a supply voltage of 1.8 V. The op-amp achieves a dc gain of 94.3 dB and a bandwidth of 45 MHz when the output capacitive load is connected to an effective load of 42.5 pF. A class-AB output stage combining a slew rate (SR) boost circuit provides a sinking current of 6 mA and an SR of 17 V/µs.

  18. Cognitive dysfunction in bipolar disorder and schizophrenia

    Bortolato, Beatrice; Miskowiak, Kamilla W; Köhler, Cristiano A;


    Cognitive impairment is a core feature of schizophrenia (SZ) and bipolar disorder (BD). A neurocognitive profile characterized by widespread cognitive deficits across multiple domains in the context of substantial intellectual impairment, which appears to antedate illness onset, is a replicated...

  19. Internet use by patients with bipolar disorder

    Bauer, Rita; Conell, Jörn; Glenn, Tasha;


    There is considerable international interest in online education of patients with bipolar disorder, yet little understanding of how patients use the Internet and other sources to seek information. 1171 patients with a diagnosis of bipolar disorder in 17 countries completed a paper-based, anonymous...... survey. 81% of the patients used the Internet, a percentage similar to the general public. Older age, less education, and challenges in country telecommunications infrastructure and demographics decreased the odds of using the Internet. About 78% of the Internet users looked online for information...... for information on bipolar disorder consulted medical professionals plus a mean of 2.3 other information sources such as books, physician handouts, and others with bipolar disorder. Patients not using the Internet consulted medical professionals plus a mean of 1.6 other information sources. The percentage...

  20. White matter microstructure alterations in bipolar disorder

    Bellani, Marcella; Perlini, Cinzia; Ferro, Adele; Cerruti, Stefania; Rambaldelli, Gianluca; Isola, Miriam; Cerini, Roberto; Dusi, Nicola; Andreone, Nicola; Balestrieri, Matteo; Mucelli, Roberto Pozzi; Tansella, Michele; Brambilla, Paolo


    Summary Genetic, neuropathological and magnetic resonance imaging findings support the presence of diffuse white matter cytoarchitectural disruption in bipolar disorder. In this study, diffusion-weighted imaging (DWI) was applied to study cortical white matter microstructure organisation in 24 patients with DSM-IV bipolar disorder and 35 matched normal controls. DWI images were obtained using a 1.5 Tesla scanner and apparent diffusion coefficient (ADC) values were determined over regions of interest placed, bilaterally, in the frontal, temporal, parietal, and occipital white matter. Significantly increased ADC values were found in bipolar patients with respect to normal controls in the right temporal lobe, left parietal lobe and bilateral occipital lobes. ADC values did not associate significantly with age or with clinical variables (p>0.05). Diffuse cortical white matter alterations on DWI in bipolar disorder denote widespread disruption of white matter integrity and may be due to altered myelination and/or axonal integrity. PMID:22687164

  1. Are rates of pediatric bipolar disorder increasing?

    Kessing, Lars Vedel; Vradi, Eleni; Andersen, Per Kragh


    Studies from the USA suggest that rates of pediatric bipolar disorder have increased since the mid-90s, but no study outside the USA has been published on the rates of pediatric bipolar disorder. Further, it is unclear whether an increase in rates reflects a true increase in the illness or more...... diagnostic attention. Using nationwide registers of all inpatients and outpatients contacts to all psychiatric hospitals in Denmark, we investigated (1) gender-specific rates of incident pediatric mania/bipolar disorder during a period from 1995 to 2012, (2) whether age and other characteristics for...... pediatric mania/bipolar disorder changed during the calendar period (1995 to 2003 versus 2004 to 2012), and (3) whether the diagnosis is more often made at first psychiatric contact in recent time compared to earlier according to gender. Totally, 346 patients got a main diagnosis of a manic episode (F30) or...

  2. Gaussian amplifier for nuclear spectrometry

    One of the major goals of nuclear spectrometry is the determination of the energy spectrum of a radioactive source. To measure this spectrum with electronic instrumentation one need to use a nuclear spectrometry chain of which the amplifier is part of, and whose filter shaping considerably influences the final energy resolution achieved. The amplifier released accomplishes a 7th order Gaussian filter shape with Taylor series approximation synthesized by the Shifted Companion Form and mounted using only electronic components availablein Brazil. The final version has been tested and the results showed a very good performance and the energy resolution achieved was equivalent to the imported models. (Author)

  3. Bipolar Harmonic encoding of CMB correlation patterns

    Joshi, Nidhi; Jhingan, Sanjay; Souradeep, Tarun; Hajian, Amir


    Deviations from statistical isotropy can be modeled in various ways, for instance, anisotropic cosmological models (Bianchi models), compact topologies and presence of primordial magnetic field. Signature of anisotropy manifests itself in CMB correlation patterns. Here we explore the symmetries of the correlation function and its implications on the observable measures constructed within the Bipolar harmonic formalism for these variety of models. Different quantifiers within the Bipolar harmo...

  4. Integrating Bipolar Disorder Management in Primary Care

    Kilbourne, Amy M.; Goodrich, David E.; O’Donnell, Allison N.; Miller, Christopher J.


    There is growing realization that persons with bipolar disorder may exclusively be seen in primary (general medical) care settings, notably because of limited access to mental health care and stigma in seeking mental health treatment. At least two clinical practice guidelines for bipolar disorder recommend collaborative chronic care models (CCMs) to help integrate mental health care to better manage this illness. CCMs, which include provider guideline support, self-management support, care ma...

  5. Long-term Treatment in Bipolar Disorder

    Meliha Zengin Eroglu; Nurgul Ozpoyraz


    Although the importance of long-term prophylactic treatment is certain in bipolar disorder, there is stil debate on how to which patients and evaluate the treatment response. Efficacious long-term treatment can reduce morbidity and mortality significantly and improve quality of life of bipolar patients. The concept of ideal response should also be defined very clearly in order to discuss the difficulties of measuring the effectiveness of the prophylactic treatment. The aims of this paper are ...


    Nieznańska, Anna; Baron, Urszula; Jaracz, Krystyna


    Background: Among the consequences of bipolar disorder there i s a decreased quality of life, including the deterioration of patients’ social functioning. Material: The paper contains an analysis of 24 major publica tions from the years 2009 to 2014, including 17 related to the assessment of quality of life and 7 articles on the bipolar patients’ social functioning. Results: There were selected 8 factors which are related with the assessment of the quality of life of persons w...

  7. Behavioral Treatment of Insomnia in Bipolar Disorder

    Kaplan, Katherine A; Harvey, Allison G.


    Sleep disturbance is common in bipolar disorder. Stimulus control and sleep restriction are powerful, clinically useful behavioral interventions for insomnia, typically delivered as part of cognitive-behavioral therapy for insomnia (CBT-I). Both involve short-term sleep deprivation. The potential for manic or hypomanic symptoms to emerge after sleep deprivation in bipolar disorder raises questions about the appropriateness of these methods for treating insomnia. In a series of patients with b...

  8. A Review of Bipolar Disorder in Adults

    Hilty, Donald M; Leamon, Martin H.; Lim, Russell F.; Kelly, Rosemary H.; Hales, Robert E.


    Objective: This article reviews the epidemiology, etiology, assessment, and management of bipolar disorder. Special attention is paid to factors that complicate treatment, including nonadherence, comorbid disorders, mixed mania, and depression. Methods: A Medline search was conducted from January of 1990 through December of 2005 using key terms of bipolar disorder, diagnosis, and treatment. Papers selected for further review included those published in English in peer-reviewed journals, with ...

  9. Bipolar Saline TURP for Large Prostate Glands

    Finley, David S.; Shawn Beck; Szabo, Richard J.


    The objective of this study was to evaluate the feasibility of bipolar transurethral resection of the prostate ( TURP) in patients with very large prostate glands and significant comorbidities. Four patients with prostate glands > 160 cc on preoperative volume measurement and ASA class three or higher underwent bipolar TURP with the Gyrus PlasmaKinetic system. Preoperative, operative, and postoperative parameters were studied. The results showed an average ASA class 3.25 (range: 3-4). The ave...

  10. Bipolar cautery forceps: An economical version

    Appukuttan Aswin; Jagadeesh S


    Context: Bipolar cautery forceps are an expensive instrument and especially in Government Medical colleges and Government Hospitals, getting a pair is a very tedious and prolonged task due to official reasons. Aims: To make a cheap and easily obtainable bipolar cautery forceps. Settings and Design: The reason for innovation was that the cautery forceps in the department were out of order and we were not getting replacements. Materials and Methods: Made from condemned and damaged forcep...