Distribution by Scientific Domains
Distribution within Engineering

Kinds of Circuits

  • amplifier circuit
  • autonomous circuit
  • brain circuit
  • chua circuit
  • control circuit
  • cortical circuit
  • cpb circuit
  • electric circuit
  • electronic circuit
  • electronics circuit
  • equivalent circuit
  • extracorporeal circuit
  • feedback circuit
  • gene circuit
  • inhibitory circuit
  • integrate circuit
  • integrated circuit
  • limbic circuit
  • linear circuit
  • logic circuit
  • matching circuit
  • microwave circuit
  • motor circuit
  • neural circuit
  • neuronal circuit
  • open circuit
  • passive circuit
  • planar circuit
  • power electronics circuit
  • reentrant circuit
  • reflex circuit
  • regulatory circuit
  • short circuit
  • tachycardia circuit
  • thalamocortical circuit

  • Terms modified by Circuits

  • circuit analysis
  • circuit board
  • circuit component
  • circuit condition
  • circuit court
  • circuit current
  • circuit design
  • circuit element
  • circuit formation
  • circuit model
  • circuit models
  • circuit parameter
  • circuit performance
  • circuit potential
  • circuit representation
  • circuit simulation
  • circuit simulator
  • circuit syst
  • circuit technology
  • circuit underlying
  • circuit voltage

  • Selected Abstracts

    The Sieve Model: An innovative process for identifying alternatives to custody evaluations

    Robert B. Silver
    This article reviews the development of the Sieve Model, conceived from dissatisfaction with adversarial processes that encouraged endless destructive fighting and depletion of financial and emotional family resources. Adversarial approaches discourage constructive problem solving and cooperation and are very hard on children. Rather than a piecemeal approach toward divorce, a systemic model was conceived. The Sieve Model is being implemented in the 20th Judicial Circuit of the State of Florida through differentiated case management, after a study revealed that protracted cases primarily involved disputes over children. Families are invited to use pertinent elements in an individualized fashion. Family law professionals are challenged to develop other solution-based efforts akin to mediation to assist families of divorce. The Sieve Model encourages participants to practice solving problems rather than creating them, decreasing divorce brutality and postjudgment conflicts. [source]

    A New Method of Electron Temperature Determination in Unmagnetized and Magnetized RF Plasmas without RF Compensating Circuit

    Y.-S. Choi
    Abstract Collected current versus applied voltage(I-V) curve of Langmuir probe in RF plasma is severely distorted by RF fluctuations leading to overestimation of electron temperature. RF compensation circuit has been used to obtain the undistorted I-V curve, yet it produces time-averaged one. A new and simple method is proposed to get time-resolved I-V curve by picking the synchronized RF signals with digital oscilloscope and Labview program. This technique is tested in magnetized helicon plasmas and unmagnetized capacitive coupled RF plasmas [source]

    NGRI Revisited: Venirepersons' Attitudes Toward the Insanity Defense,

    Brooke Butler
    Three hundred venirepersons from the 12th Judicial Circuit in Sarasota, Florida completed the following booklet of stimulus materials: one question measuring participants' level of support for insanity defense; a 16-item measure assessing participants' attitudes toward the myths associated with the insanity defense, the legal definitions of insanity, and mental illness; a case scenario; verdict preference; and standard demographic questions. Level of support for the insanity defense was significantly related to participants' attitudes toward legal standards of insanity, mental illness, and the myths associated with the insanity defense. In addition, results indicated that level of support for the insanity defense, age, educational level, occupation, type of prior jury service, and political views were significantly related to verdict preference. Notably, three factors that have been found to impact verdict preference in previous research failed to do so in the current study: participants' experience with psychological disorders; participants' exposure to psychotropic medications; and participants' experience with psychologists or psychiatrists. The findings both replicate and extend earlier findings by suggesting that attitudes toward the insanity defense are more complex than previously imagined. [source]

    Different Forms of Ventricular Tachycardia Involving the Left Anterior Fascicle in Nonischemic Cardiomyopathy: Critical Sites of the Reentrant Circuit in Low-Voltage Areas

    Introduction: The purpose of this study was to examine the reentrant circuit of ventricular tachycardias (VTs) involving the left anterior fascicle (LAF) in nonischemic cardiomyopathy. Methods and Results: Six patients with nonischemic cardiomyopathy presented with VTs involving the LAF. Potentials in the diastolic or presystolic phase of the VT were identified close to the LAF in 3 patients and in the mid or inferior left ventricular (LV) septum in 3 patients. Superimposed on a CARTO or NavX 3-dimensional voltage map, the diastolic and presystolic potentials were recorded within or at the border of a low-voltage zone in the LV septum in all cases. In 2 patients, both left bundle fascicles participated in the reentrant circuit including a possible interfascicular VT in one case. Ablation targeting the diastolic or presystolic potentials near the LAF or in the midinferior LV septum eliminated the VTs in all patients with the occurrence of a left posterior fascicular block and the delayed occurrence of a complete atrioventricular block in each one patient. During the follow-up of 23 ± 20 months after ablation, 4 patients were free of ventricular tachyarrhythmias. Due to detoriation of heart failure, one patient died after 12 months and one patient underwent heart transplantation after 40 months. Conclusions: Slow conduction in diseased myocardium close to the LAF or in the middle and inferior aspects of the LV septum may represent the diastolic pathway of VT involving the LAF. [source]

    Quantitative Analysis of the Duration of Slow Conduction in the Reentrant Circuit of Ventricular Tachycardia After Myocardial Infarction

    Background: Few data are available to define the circuits in ventricular tachycardia (VT) after myocardial infarction and the conduction time (CT) through the zone of slow conduction (SCZ). This study assessed the CT of the SCZ and identified different reentrant circuits. Methods: During VTs, concealed entrainment (CE) was attempted. The SCZ was identified by a difference between postpacing interval (PPI) and VT cycle length (VTcl) ,30 ms. Since the CT in the normally conducting part of the VT circuit is constant during VT and CE, a CE site within the reentrant circuit with (S-QRS)/PPI , 50% was classified as an inner reentry in which the entire circuit was within the scar, and a CE site with (S-QRS)/PPI < 50% as a common reentry in which part of the circuit was within the scar and part out of the scar. Results: CE was achieved in 20 VTs (12 patients). Six VTs (30%) with a (S-QRS)/PPI ,50% were classified as inner reentry and 14 VTs (70%) with a (S-QRS)/PPI <50% during CE mapping as common reentry. The EG-QRS interval (308 ± 73 ms vs 109 ± 59 ms, P < 0.0001) was significantly longer and the incidence of systolic potentials higher (4/6 vs 0/12, P < 0.001) in the inner reentry group. For the 14 VTs with a common reetry, the CT of the SCZ was 348 ± 73 ms, while the CT in the normal area was 135 ± 50 ms. Conclusion: According to the proposed classification, 30% of VTs after myocardial infarction had an entire reentrant circuit within the scar. In VTs with a common reentrant circuit, the CT of the SCZ is approximately four times longer than the CT in the normal area, accounting for more than 70% of VTcl. [source]

    Cocaine- and Amphetamine-Regulated Transcript is Present in Hypothalamic Neuroendocrine Neurones and is Released to the Hypothalamic-Pituitary Portal Circuit

    P. J. Larsen
    Abstract Cocaine- and amphetamine-regulated transcript (CART) is present in a number of hypothalamic nuclei. Besides actions in circuits regulating feeding behaviour and stress responses, the hypothalamic functions of CART are largely unknown. We report that CART immunoreactivity is present in hypothalamic neuroendocrine neurones. Adult male rats received a systemic injection of the neuronal tracer Fluorogold (FG) 2 days before fixation, and subsequent double- and triple-labelling immunoflourescence analysis demonstrated that neuroendocrine CART-containing neurones were present in the anteroventral periventricular, supraoptic, paraventricular (PVN) and periventricular nuclei of the hypothalamus. In the PVN, CART-positive neuroendocrine neurones were found in all of cytoarchitectonically identified nuclei. In the periventricular nucleus, approximately one-third of somatostatin cells were also CART-immunoreactive. In the medial parvicellular subnucleus of the PVN, CART and FG coexisted with thyrotrophin-releasing hormone, whereas very few of the corticotrophin-releasing hormone containing cells were CART-immunoreactive. In the arcuate nucleus, CART was extensively colocalized with pro-opiomelanocortin in the ventrolateral part, but completely absent from neuroendocrine neurones of the dorsomedial part. To assess the possible role of CART as a hypothalamic-releasing factor, immunoreactive CART was measured in blood samples from the long portal vessels connecting the median eminence with the anterior pituitary gland. Adult male rats were anaesthetized and the infundibular stalk exposed via a transpharyngeal approach. The long portal vessels were transected and blood collected in 30-min periods (one prestimulatory and three poststimulatory periods). Compared to systemic venous plasma samples, baseline concentrations of immunoreactive CART were elevated in portal plasma. Exposure to sodium nitroprusside hypotension triggered a two-fold elevation of portal CART42-89 immunoreactivity throughout the 90-min stimulation period. In contrast, the concentration of portal plasma CART immunoreactivity dropped in the vehicle infused rats. The current study provides further evidence that CART is a neuroendocrine-releasing factor with a possible impact on anterior pituitary function during states of haemodynamic stress. [source]

    The Incidence and Structure of Conflict on the U.S. Court of Appeals for the Federal Circuit

    LAW & POLICY, Issue 1 2001
    Isaac Unah
    In 1982, Congress established the Court of Appeals for the Federal Circuit, a specialized court, with the objective of reducing judicial conflict and harmonizing circuit law in specific policy areas of special complexity. This article examines the incidence and determinants of judicial conflict on the U.S. courts of appeals, focusing specifically on the Federal Circuit. Using international trade and customs regulation cases decided during the 1982 to 1995 terms, the analysis reviews three possible explanations of judicial conflict: policy-oriented, sociolegal, and organizational. The analysis shows that conflict appears in 8.4 percent of the trade and customs regulation decisions rendered by the Federal Circuit during the period of study. The policy direction of Federal Circuit decisions and the court's hierarchical relationship with lower specialized courts provide the strongest explanation for the emergence of conflict on the court. Organizational factors such as panel composition evinced rather anemic explanatory capacity. The results raise an important functional similarity between the Federal Circuit and the generalist courts of appeals. Contrary to the laments of legal practitioners that conflict on the Federal Circuit is excessive relative to conflict on the generalist circuit courts, this analysis finds little support for that claim. Rather, the level of overt conflict on the court is actually low and corroborates conflict levels that have been reported for other U.S. courts of appeals. [source]

    Seventh Circuit says arbitrators decide on consolidation

    Article first published online: 8 MAY 200
    The American Arbitration Assocation opens two new offices abroad. Also, a Seventh Circuit decision on consolidating arbitration cases points practitioners to dealing with the issue long before arbitrators or courtrooms enter the picture [source]

    Reentry Within the Cavotricuspid Isthmus: An Isthmus Dependent Circuit

    Background: We describe a new cavotricuspid isthmus (CTI) circuit. Methods: This study includes 8 patients referred for atrial flutter (AFL) ablation whose tachycardia circuit was confined to the septal CTI and the os of the coronary sinus (CSOS) region. Entrainment mapping was performed within the CTI, CSOS, and other right atrial annular sites (tricuspid annulus (TA)). Electroanatomic mapping was available in 2 patients. Results: Sustained AFL occurred in all patients with mean tachycardia cycle length (TCL) of 318 ± 54 (276 , 420) ms. During tachycardia, fractionated or double potentials were recorded at either the septal CTI and/or the region of CSOS in all, and concealed entrainment with post-pacing interval (PPI) , TCL , 25 ms occurred in this area; but manifest entrainment with PPI > TCL was demonstrated from the anteroinferior CTI and other annular sites in 7/8 patients. In one, tachycardia continued with conduction block at the anteroinferior CTI during ablation. Up to three different right atrial activation patterns (identical TCL) were observed. The tachycardia showed a counterclockwise (CCW) pattern in 6, a clockwise pattern in 2, and simultaneous activation of both low lateral right atrium and septum in 5. Electroanatomic mapping was available in 2, showing an early area arising from the septal CTI in 1, and a CCW activation sequence along the TA in another. Radiofrequency application to the septal CTI terminated tachycardia in 4, and tachycardia no longer inducible in all. Conclusions: We describe a tachycardia circuit confined to the septal CTI/CSOS region, and hypothesize that this circuit involves slow conduction within the CTI and around the CSOS, which acts as a central obstacle. [source]

    Is the Fascicle of Left Bundle Branch Involved in the Reentrant Circuit of Verapamil-Sensitive Idiopathic Left Ventricular Tachycardia?

    The exact reentrant circuit of the verapamil-sensitive idiopathic left VT with a RBBB configuration remains unclear. Furthermore, if the fascicle of left bundle branch is involved in the reentrant circuit has not been well studied. Forty-nine patients with verapamil-sensitive idiopathic left VT underwent electrophysiological study and RF catheter ablation. Group I included 11 patients (10 men, 1 woman; mean age 25 ± 8 years) with left anterior fascicular block (4 patients), or left posterior fascicular block (7 patients) during sinus rhythm. Group II included 38 patients (29 men, 9 women; mean age 35 ± 16 years) without fascicular block during sinus rhythm. Duration of QRS complex during sinus rhythm before RF catheter ablation in group I patients was significant longer than that of group II patients (104 ± 12 vs 95 ± 11 ms, respectively, P = 0.02). Duration of QRS complex during VT was similar between group I and group II patients (141 ± 13 vs 140 ± 14 ms, respectively, P = 0.78). Transitional zones of QRS complexes in the precordial leads during VT were similar between group I and group II patients. After ablation, the QRS duration did not prolong in group I or group II patients (104 ± 11 vs 95 ± 10 ms, P = 0.02); fascicular block did not occur in group II patients. Duration and transitional zone of QRS complex during VT were similar between the two groups, and new fascicular block did not occur after ablation. These findings suggest the fascicle of left bundle branch may be not involved in the antegrade limb of reentry circuit in idiopathic left VT. (PACE 2003; 26:1986,1992) [source]

    Amorphous silicon based p-i-i-n photodetectors for point-of-care testing

    Marc Sämann
    Abstract Modern medical diagnostics demands point-of-care testing (POCT) systems for quick tests in clinical or out-patient environments. This investigation combines the Reflectometric Interference Spectroscopy (RIfS) with thin film technology for a highly sensitive, direct optical and label-free detection of proteins, e.g. inflammation or cardiovascular markers. Amorphous silicon (a-Si) based thin film photodetectors replace the so far needed spectrometer and permit downsizing of the POCT system. Photodetectors with p-i-i-n structure adjust their spectral sensitivity according to the applied read-out voltage. The use of amorphous silicon carbide in the p-type and the first intrinsic layer enhances the sensitivity through very low dark currents of the photodetectors and enables the adjustment of their absorption characteristics. Integrating the thin film photodetectors on the rear side of the RIfS substrate eliminates optical losses and distortions, as compared to the standard RIfS setup. An integrated Application Specific Integrated Circuit (ASIC) chip performs a current-frequency conversion to accurately detect the photocurrent of up to eight parallel photodetector channels. In addition to the optimization of the photo-detectors, this contribution presents first successful direct optical and label-free RIfS measurements of C-reactive protein (CRP) and D-dimer in buffer solution in physiological relevant concentrations. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

    Patent thickets, courts, and the market for innovation

    Alberto Galasso
    We study how fragmentation of patent rights and the formation of the Court of Appeals for the Federal Circuit (CAFC) affected the duration of patent disputes, and thus the speed of technology diffusion through licensing. We develop a model of patent litigation which predicts faster settlement when patent rights are fragmented and when there is less uncertainty about court outcomes, as was associated with the "pro-patent shift" of the CAFC. We confirm these predictions empirically using a data set that covers patent suits in U.S. district courts during the period 1975,2000. Finally, we analyze how fragmentation affects total settlement delay, considering both the reduction in dispute duration and the increase in the number of patent negotiations. [source]

    Comparison of Two Types of Neonatal Extracorporeal Life Support Systems With Pulsatile and Nonpulsatile Flow

    ARTIFICIAL ORGANS, Issue 11 2009
    Nikkole Haines
    Abstract We compared the effects of two neonatal extracorporeal life support (ECLS) systems on circuit pressures and surplus hemodynamic energy levels in a simulated ECLS model. The clinical set-up included the Jostra HL-20 heart,lung machine, either the Medtronic ECMO (0800) or the MEDOS 800LT systems with company-provided circuit components, a 10 Fr arterial cannula, and a pseudo-patient. We tested the system in nonpulsatile and pulsatile flow modes at two flow rates using a 40/60 glycerin/water blood analog, for a total of 48 trials, with n = 6 for each set-up. The pressure drops over the Medtronic ECLS were significantly higher than those over the MEDOS system regardless of the flow rate or perfusion mode (144.8 ± 0.2 mm Hg vs. 35.7 ± 0.2 mm Hg, respectively, at 500 mL/min in nonpulsatile mode, P < 0.001). The preoxygenator mean arterial pressures were significantly increased and the precannula hemodynamic energy values were decreased with the Medtronic ECLS circuit. These results suggest that the MEDOS ECLS circuit better transmits hemodynamic energy to the patient, keeps mean circuit pressures lower, and has lower pressure drops than the Medtronic Circuit. [source]

    Optimizing the Circuit of a Pulsatile Extracorporeal Life Support System in Terms of Energy Equivalent Pressure and Surplus Hemodynamic Energy

    ARTIFICIAL ORGANS, Issue 11 2009
    Choon Hak Lim
    Abstract:, The nonpulsatile blood flow obtained using standard cardiopulmonary bypass (CPB) circuits is still generally considered an acceptable, nonphysiologic compromise with few disadvantages. However, numerous reports have concluded that pulsatile perfusion during CPB achieves better multiorgan response postoperatively. Furthermore, pulsatile flow during CPB has been consistently recommended in pediatric and high-risk patients. However, most (80%) of the total hemodynamic energy generated by a pulsatile pump is absorbed by the components of the extracorporeal circuit and only a small portion of the pulsatile energy is delivered to the patient. Therefore, we considered that optimizations of CPB unit and extracorporeal life support (ECLS) system circuit components were needed to deliver sufficient pulsatile flow. In addition, energy equivalent pressure, surplus hemodynamic energy, and total hemodynamic energy, calculated using pressure and flow waveforms, were used to evaluate the pulsatilities of pulsatile CPB and ECLS systems. [source]

    The impact of death qualification, belief in a just world, legal authoritarianism, and locus of control on venirepersons' evaluations of aggravating and mitigating circumstances in capital trials,

    Brooke Butler Ph.D.
    The purpose of this study was to investigate the impact of death qualification, belief in a just world (BJW), legal authoritarianism (RLAQ), and locus of control (LOC) on venirepersons' evaluations of aggravating and mitigating circumstances in capital trials. 212 venirepersons from the 12th Judicial Circuit in Bradenton, FL, completed a booklet that contained the following: one question that measured their attitudes toward the death penalty; one question that categorized their death-qualification status; the BJW, LOC, and RLAQ scales; a summary of the guilt and penalty phases of a capital case; a 26-item measure that required participants to evaluate aggravators, nonstatutory mitigators, and statutory mitigators on a 6-point Likert scale; sentence preference; and standard demographic questions. Results indicated that death-qualified venirepersons were more likely to demonstrate higher endorsements of aggravating factors and lower endorsements of both nonstatutory and statutory mitigating factors. Death-qualified participants were also more likely to have a high belief in a just world, espouse legal authoritarian beliefs, and exhibit an internal locus of control. Findings also suggested that venirepersons with a low belief in a just world and an external locus of control demonstrated higher endorsements of statutory mitigators. Participants with legal authoritarian beliefs revealed higher endorsements of aggravators and lower endorsements of nonstatutory mitigators. Legal implications and applications are discussed. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Circuits and systems in stress.


    Abstract This paper follows the preclinical work on the effects of stress on neurobiological and neuroendocrine systems and provides a comprehensive working model for understanding the pathophysiology of posttraumatic stress disorder (PTSD). Studies of the neurobiology of PTSD in clinical populations are reviewed. Specific brain areas that play an important role in a variety of types of memory are also preferentially affected by stress, including hippocampus, amygdala, medial prefrontal cortex, and cingulate. This review indicates the involvement of these brain systems in the stress response, and in learning and memory. Affected systems in the neural circuitry of PTSD are reviewed (hypothalamic-pituitary-adrenal axis (HPA-axis), catecholaminergic and serotonergic systems, endogenous benzodiazepines, neuropeptides, hypothalamic-pituitary-thyroid axis (HPT-axis), and neuro-immunological alterations) as well as changes found with structural and functional neuroimaging methods. Converging evidence has emphasized the role of early-life trauma in the development of PTSD and other trauma-related disorders. Current and new targets for systems that play a role in the neural circuitry of PTSD are discussed. This material provides a basis for understanding the psychopathology of stress-related disorders, in particular PTSD. Depression and Anxiety 16:14,38, 2002. © 2002 Wiley-Liss, Inc. [source]

    Cyclical Clusters in Global Circuits: Overlapping Spaces in Furniture Trade Fairs

    ECONOMIC GEOGRAPHY, Issue 4 2008
    Dominic Power
    abstract This article contributes to an understanding of temporary or event-based economic phenomena in economic and industrial geography by drawing on research conducted on the furniture and interior design industry. It argues that trade fairs should be seen not simply as temporary industry gatherings, but as central, though temporary, spaces for knowledge and market processes that symbolize microcosms of the industry they represent and function as effective marketplaces. It suggests that these temporary events should be viewed not as isolated from one another, but as arranged together in an almost continual global circuit. In this sense, trade fairs are less temporary clusters than they are cyclical clusters; they are complexes of overlapping spaces that are scheduled and arranged in such a way that spaces can be reproduced, reenacted, and renewed over time. Although actual fairs are short-lived events, their presence in the business cycle has lasting consequences for the organization of markets and industries and for the firms of which they are comprised. [source]

    The Institutional Trap in the Czech Rental Sector: Nested Circuits of Power, Space, and Inequality

    ECONOMIC GEOGRAPHY, Issue 4 2005
    Stefan Buzar
    Abstract: An "institutional trap" is a sequence of misplaced regulatory steps that have increased the costs of institutional transformation to the level at which inefficient structures can remain stable, despite changes in the external economic environment. This is a common occurrence in Central and Eastern Europe because of the path-dependent nature of the postsocialist transformation process. This article examines the organizational and territorial transformations of housing, utility, and social welfare policies in the Czech Republic through a comparative analysis of institutional power geometries and household expenditures at the national scale. The results indicate that the Czech Republic is facing an institutional trap in the restructuring of its rent control and social welfare policies. The trap operates within three nested circuits: the power geometries of postsocialist reforms, the geographies of housing prices and social welfare, and the consumption patterns of disadvantaged households. The lock-in created by the trap can be resolved only through carefully targeted and synchronized social support and housing investment programs, parallel to rent liberalization. This article argues for comprehensive, rather than partial, solutions to the institutional trap and emphasizes the need for a deeper understanding of the relationships among institutions, space, and inequality. [source]

    Pregabalin Exerts Oppositional Effects on Different Inhibitory Circuits in Human Motor Cortex: A Double-blind, Placebo-controlled Transcranial Magnetic Stimulation Study

    EPILEPSIA, Issue 5 2006
    Nicolas Lang
    Summary:,Purpose: To explore acute effects of pregabalin (PGB) on human motor cortex excitability with transcranial magnetic stimulation (TMS). Methods: PGB, 600 mg/day, was orally administered in 19 healthy subjects twice daily in a randomized, double-blind, placebo-controlled crossover design. Several measures of motor cortex excitability were tested with single- and paired-pulse TMS. Results: Mean short-interval intracortical inhibition (SICI) was reduced after PGB (74 ± 7% of unconditioned response) compared with placebo (60 ± 6% of unconditioned response). In contrast, mean long-interval intracortical inhibition (LICI) was increased by PGB (26 ± 4% of unconditioned response) compared with placebo (45 ± 8% of unconditioned response), and mean cortical silent period (CSP) showed an increase from 139 ± 8 ms or 145 ± 8 ms after placebo to 162 ± 7 ms or 161 ± 10 ms after PGB. Motor thresholds, intracortical facilitation, and corticospinal excitability were unaffected. Conclusions: The observed excitability changes with oppositional effects on SICI and LICI or CSP suggest ,-aminobutyric acid (GABA)B -receptor activation. They are markedly distinct from those induced by gabapentin, although both PGB and gabapentin are thought to mediate their function by binding to the ,(2)-, subunit of voltage-gated calcium channels. Conversely, the TMS profile of PGB shows striking similarities with the pattern evoked by the GABA-reuptake inhibitor tiagabine. [source]

    Printed Sub-2 V Gel-Electrolyte-Gated Polymer Transistors and Circuits

    Yu Xia
    Abstract The fabrication and characterization of printed ion-gel-gated poly(3-hexylthiophene) (P3HT) transistors and integrated circuits is reported, with emphasis on demonstrating both function and performance at supply voltages below 2,V. The key to achieving fast sub-2,V operation is an unusual gel electrolyte based on an ionic liquid and a gelating block copolymer. This gel electrolyte serves as the gate dielectric and has both a short polarization response time (<1,ms) and a large specific capacitance (>10,µF cm,2), which leads simultaneously to high output conductance (>2,mS mm,1), low threshold voltage (<1,V) and high inverter switching frequencies (1,10,kHz). Aerosol-jet-printed inverters, ring oscillators, NAND gates, and flip-flop circuits are demonstrated. The five-stage ring oscillator operates at frequencies up to 150,Hz, corresponding to a propagation delay of 0.7 ms per stage. These printed gel electrolyte gated circuits compare favorably with other reported printed circuits that often require much larger operating voltages. Materials factors influencing the performance of the devices are discussed. [source]

    Nanoscale Single-Crystal Circuits: Assembly of Nanoscale Organic Single-Crystal Cross-Wire Circuits (Adv. Mater.

    ADVANCED MATERIALS, Issue 42 2009
    Organic single-crystal circuits with versatile functions, such as inverters, NOR, and NAND gate, can be assembled by nanomechanical manipulation of nanowires of CuPc, F16CuPc and SnO2:Sb, report Thomas Bjornholm, Wenping Hu, and co-workers on p. 4234. The circuits show ultralow power consumption (40 pW per logic gate) and high voltage gain. In combination with generic "bottom-up" assembly methods developed for nanowires, this opens new opportunities in organic nanoelectronics and for highly sophisiticated integrated logic circuits [source]

    Assembly of Nanoscale Organic Single-Crystal Cross-Wire Circuits

    ADVANCED MATERIALS, Issue 42 2009
    Qingxin Tang
    Organic single-crystal transistors and circuits can be assembled by nanomechanical manipulation of nanowires of CuPc, F16CuPc, and SnO2:Sb. The crossed bar devices have low operational voltage, high mobility and are stable in air. They can be combined into circuits, providing varied functions including inverters and NOR and NAND logic gates, opening new opportunities for organic nanoelectronics and highly sophisticated integrated logic devices. [source]

    Flexible Electronics: Ultrathin Silicon Circuits With Strain-Isolation Layers and Mesh Layouts for High-Performance Electronics on Fabric, Vinyl, Leather, and Paper (Adv. Mater.

    ADVANCED MATERIALS, Issue 36 2009
    The cover shows a silicon integrated circuit on a paper substrate. The system consists of ultrathin devices electrically and mechanically interconnected with stretchable, serpentine ribbons. A low modulus elastomeric adhesive isolates the circuit from strains associated with bending and folding the paper. This strategy provides a route to high quality electronics on paper, vinyl, leather and other unusual substrates, as reported by John Rogers and co-workers on p. 3703. [source]

    Ultrathin Silicon Circuits With Strain-Isolation Layers and Mesh Layouts for High-Performance Electronics on Fabric, Vinyl, Leather, and Paper

    ADVANCED MATERIALS, Issue 36 2009
    Dae-Hyeong Kim
    We present various stretchable high-performance CMOS circuit demonstrations on unconventional substrates, such as fabric, vinyl, leather, and paper. Electronics on such substrates, especially paper, open up new and important application possibilities for electronics. Theoretical analysis reveals the underlying mechanics of these systems; electrical tests under mechanical cycling demonstrate the robustness of the designs. [source]

    Miniaturization of a Laser Doppler Blood Flow Sensor by System-in-Package Technology: Fusion of an Optical Microelectromechanical Systems Chip and Integrated Circuits

    Wataru Iwasaki Member
    Abstract We have developed the first and the smallest blood flow sensor composed of integrated circuits (ICs) fused with an optical microelectromechanical systems (MEMS) chip using system-in-package (SiP) technologies for application in a healthcare monitoring system. The probe of this blood flow sensor consists of three layers, and the optical MEMS chip is stacked as the top layer. Through silicon via (TSV), vertical-cavity surface-emitting laser (VCSEL) and cavities enable wafer-level packaging of the optical MEMS chip. The other two layers consisting of ICs are highly densified by SiP technology, and the volume of the probe is miniaturized to about one-sixth of our previously reported integrated laser Doppler blood flowmeter, an MEMS blood flow sensor to which SiP technology was not applied. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

    View of Technical Committee on Electronic Circuits on the progress of electronic circuit technologies in the past decade and the future prospects

    Shigetaka Takagi
    No abstract is available for this article. [source]

    Nanoscale Logic Circuits: Hybrid Complementary Logic Circuits of One-Dimensional Nanomaterials with Adjustment of Operation Voltage (Adv. Mater.

    ADVANCED MATERIALS, Issue 21 2009
    A new layout of complementary logic circuits based on p-channel carbon nanotube and n-channel zinc oxide nanowire transistors is presented by Takhee Lee and co-workers on p. 2156. The processing is a hybrid approach, combining advantageous characteristic functions for the modulation of the current and operating voltage in transistors through proton radiation-generated charges, allowing a simple method of designing favorable logic circuits. [source]

    Hybrid Complementary Logic Circuits of One-Dimensional Nanomaterials with Adjustment of Operation Voltage

    ADVANCED MATERIALS, Issue 21 2009
    Gunho Jo
    A new layout of complementary logic circuits based on p-channel carbon nanotube and n-channel zinc oxide nanowire transistors is presented, providing a hybrid approach to combine advantageous characteristic functions for the modulation of the current and operating voltage in transistors through proton radiation-generated charges, which allow a simple way to design favorable logic circuits. [source]

    High-Performance Zinc Oxide Transistors and Circuits Fabricated by Spray Pyrolysis in Ambient Atmosphere

    ADVANCED MATERIALS, Issue 21 2009
    Aneeqa Bashir
    The use of a simple deposition technique, namely spray pyrolysis, for the fabrication of high-mobility, low-voltage ZnO transistors and simple integrated circuits is demonstrated. The method is compatible with large-area deposition and could potentially address both the issue of manufacturing cost and high operating voltages. [source]

    Carbon Nanotube Field-Effect Transistors: Towards Entire-Carbon-Nanotube Circuits: The Fabrication of Single-Walled-Carbon-Nanotube Field-Effect Transistors with Local Multiwalled-Carbon-Nanotube Interconnects (Adv. Mater.

    ADVANCED MATERIALS, Issue 13 2009
    Towards entire carbon nanotube (CNT) circuits: single-walled CNTs serve as channels (lowest layer) and multi-walled CNTs serve as interconnects (vertical vias and second/third layers). The polarity of the channel (p- or n-type) was defined by metals with different working functions at the contact points (the yellow and green contacts in the lowest layer). More details on single-walled CNT field-effect transistors with multiwalled CNTs as local interconnects can be found in the article by Xuelei Liang, Lian-Mao Peng, and co-workers on p. 1339. [source]