Heterojunction fully depleted SOI-TFET with oxide/source overlap

NASA Astrophysics Data System (ADS)

Chander, Sweta; Bhowmick, B.; Baishya, S.

2015-10-01

In this work, a hetero-junction fully depleted (FD) Silicon-on-Insulator (SOI) Tunnel Field Effect Transistor (TFET) nanostructure with oxide overlap on the Germanium-source region is proposed. Investigations using Synopsys Technology Computer Aided Design (TCAD) simulation tools reveal that the simple oxide overlap on the Germanium-source region increases the tunneling area as well as the tunneling current without degrading the band-to-band tunneling (BTBT) and improves the device performance. More importantly, the improvement is independent of gate overlap. Simulation study shows improvement in ON current, subthreshold swing (SS), OFF current, ION/IOFF ration, threshold voltage and transconductance. The proposed device with hafnium oxide (HfO2)/Aluminium Nitride (AlN) stack dielectric material offers an average subthreshold swing of 22 mV/decade and high ION/IOFF ratio (∼1010) at VDS = 0.4 V. Compared to conventional TFET, the Miller capacitance of the device shows the enhanced performance. The impact of the drain voltage variation on different parameters such as threshold voltage, subthreshold swing, transconductance, and ION/IOFF ration are also found to be satisfactory. From fabrication point of view also it is easy to utilize the existing CMOS process flows to fabricate the proposed device.

A two-dimensional (2D) analytical subthreshold swing and transconductance model of underlap dual-material double-gate (DMDG) MOSFET for analog/RF applications

NASA Astrophysics Data System (ADS)

Narendar, Vadthiya; Rai, Saurabh; Tiwari, Siddharth; Mishra, R. A.

2016-12-01

The double-gate (DG) metal-oxide-semiconductor field effect transistors (MOSFETs) are the choice of technology in sub -100 nm regime of leading microelectronics industry. To enhance the analog and RF performance of DG MOSFET, an underlap dual-material (DM) DG MOSFET device structure has been considered because, it has the advantages of both underlap as well as that of dual-material gate (DMG). A 2D analytical surface potential, subthreshold current, subthreshold swing as well as transconductance modelling of underlap DMDG MOSFET has been done by solving the Poisson's equation. It has also been found that, numerically simulated data approves the analytically modelled data with commendable accuracy. As underlap length (Lun) increases, a substantial reduction of subthreshold current due to enhanced gate control over channel regime is observed. DMG structure facilitates to improve the average velocity of carriers which leads to superior drive current of the device. The underlap DMDG MOSFET device structure demonstrates an ameliorated subthreshold characteristic. The analog figure of merits (FOMs) such as transconductance (gm), transconductance generation factor (TGF), output conductance (gd), early voltage (VEA), intrinsic gain (AV) and RF FOMs namely cut-off frequency (fT), gain frequency product (GFP), transconductance frequency product (TFP) and gain transconductance frequency product (GTFP) have been evaluated. The aforesaid analysis revels that, the device is best suited for communication related Analog/RF applications.

Fabrication of amorphous InGaZnO thin-film transistor with solution processed SrZrO3 gate insulator

NASA Astrophysics Data System (ADS)

Takahashi, Takanori; Oikawa, Kento; Hoga, Takeshi; Uraoka, Yukiharu; Uchiyama, Kiyoshi

2017-10-01

In this paper, we describe a method of fabrication of thin film transistors (TFTs) with high dielectric constant (high-k) gate insulator by a solution deposition. We chose a solution processed SrZrO3 as a gate insulator material, which possesses a high dielectric constant of 21 with smooth surface. The IGZO-TFT with solution processed SrZrO3 showed good switching property and enough saturation features, i.e. field effect mobility of 1.7cm2/Vs, threshold voltage of 4.8V, sub-threshold swing of 147mV/decade, and on/off ratio of 2.3×107. Comparing to the TFTs with conventional SiO2 gate insulator, the sub-threshold swing was improved by smooth surface and high field effect due to the high dielectric constant of SrZrO3. These results clearly showed that use of solution processed high-k SrZrO3 gate insulator could improve sub-threshold swing. In addition, the residual carbon originated from organic precursors makes TFT performances degraded.

Adolescent subthreshold-depression and anxiety: psychopathology, functional impairment and increased suicide risk.

PubMed

Balázs, Judit; Miklósi, Mónika; Keresztény, Agnes; Hoven, Christina W; Carli, Vladimir; Wasserman, Camilla; Apter, Alan; Bobes, Julio; Brunner, Romuald; Cosman, Doina; Cotter, Pádraig; Haring, Christian; Iosue, Miriam; Kaess, Michael; Kahn, Jean-Pierre; Keeley, Helen; Marusic, Dragan; Postuvan, Vita; Resch, Franz; Saiz, Pilar A; Sisask, Merike; Snir, Avigal; Tubiana, Alexandra; Varnik, Airi; Sarchiapone, Marco; Wasserman, Danuta

2013-06-01

 Subthreshold-depression and anxiety have been associated with significant impairments in adults. This study investigates the characteristics of adolescent subthreshold-depression and anxiety with a focus on suicidality, using both categorical and dimensional diagnostic models.  Data were drawn from the Saving and Empowering Young Lives in Europe (SEYLE) study, comprising 12,395 adolescents from 11 countries. Based on self-report, including Beck Depression Inventory-II (BDI-II), Zung Self-Rating Anxiety Scale (SAS), Strengths and Difficulties Questionnaire (SDQ) and Paykel Suicide Scale (PSS) were administered to students. Based on BDI-II, adolescents were divided into three groups: nondepressed, subthreshold-depressed and depressed; based on the SAS, they were divided into nonanxiety, subthreshold-anxiety and anxiety groups. Analyses of Covariance were conducted on SDQ scores to explore psychopathology of the defined groups. Logistic regression analyses were conducted to explore the relationships between functional impairments, suicidality and subthreshold and full syndromes.  Thirty-two percent of the adolescents were subthreshold-anxious and 5.8% anxious, 29.2% subthreshold-depressed and 10.5% depressed, with high comorbidity. Mean scores of SDQ of subthreshold-depressed/anxious were significantly higher than the mean scores of the nondepressed/nonanxious groups and significantly lower than those of the depressed/anxious groups. Both subthreshold and threshold-anxiety and depression were related to functional impairment and suicidality. Subthreshold-depression and subthreshold-anxiety are associated with an increased burden of disease and suicide risk. These results highlight the importance of early identification of adolescent subthreshold-depression and anxiety to minimize suicide. Incorporating these subthreshold disorders into a diagnosis could provide a bridge between categorical and dimensional diagnostic models. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.

Decreases in perceived maternal criticism predict improvement in subthreshold psychotic symptoms in a randomized trial of family-focused therapy for individuals at clinical high risk for psychosis.

PubMed

O'Brien, Mary P; Miklowitz, David J; Cannon, Tyrone D

2015-12-01

Perceived criticism (PC) is a measure of how much criticism from 1 family member "gets through" to another. PC ratings have been found to predict the course of psychotic disorders, but questions remain regarding whether psychosocial treatment can effectively decrease PC, and whether reductions in PC predict symptom improvement. In a sample of individuals at high risk for psychosis, we examined a) whether Family Focused Therapy for Clinical High-Risk (FFT-CHR), an 18-session intervention that consists of psychoeducation and training in communication and problem solving, brought about greater reductions in perceived maternal criticism, compared to a 3-session family psychoeducational intervention; and b) whether reductions in PC from baseline to 6-month reassessment predicted decreases in subthreshold positive symptoms of psychosis at 12-month follow-up. This study was conducted within a randomized controlled trial across 8 sites. The perceived criticism scale was completed by 90 families prior to treatment and by 41 families at 6-month reassessment. Evaluators, blind to treatment condition, rated subthreshold symptoms of psychosis at baseline, 6- and 12-month assessments. Perceived maternal criticism decreased from pre- to posttreatment for both treatment groups, and this change in criticism predicted decreases in subthreshold positive symptoms at 12-month follow-up. This study offers evidence that participation in structured family treatment is associated with improvement in perceptions of the family environment. Further, a brief measure of perceived criticism may be useful in predicting the future course of attenuated symptoms of psychosis for CHR youth. (c) 2015 APA, all rights reserved).

HCN1 channels in cerebellar Purkinje cells promote late stages of learning and constrain synaptic inhibition

PubMed Central

Rinaldi, Arianna; Defterali, Cagla; Mialot, Antoine; Garden, Derek L F; Beraneck, Mathieu; Nolan, Matthew F

2013-01-01

Neural computations rely on ion channels that modify neuronal responses to synaptic inputs. While single cell recordings suggest diverse and neurone type-specific computational functions for HCN1 channels, their behavioural roles in any single neurone type are not clear. Using a battery of behavioural assays, including analysis of motor learning in vestibulo-ocular reflex and rotarod tests, we find that deletion of HCN1 channels from cerebellar Purkinje cells selectively impairs late stages of motor learning. Because deletion of HCN1 modifies only a subset of behaviours involving Purkinje cells, we asked whether the channel also has functional specificity at a cellular level. We find that HCN1 channels in cerebellar Purkinje cells reduce the duration of inhibitory synaptic responses but, in the absence of membrane hyperpolarization, do not affect responses to excitatory inputs. Our results indicate that manipulation of subthreshold computation in a single neurone type causes specific modifications to behaviour. PMID:24000178

Review of health and risk-behaviours, mental health problems and suicidal behaviours in young Europeans on the basis of the results from the EU-funded Saving and Empowering Young Lives in Europe (SEYLE) study.

PubMed

Wasserman, Danuta

2016-12-23

An estimated 800 000 suicide deaths occur worldwide. The global suicide rate is 11.4 per 100 000 population; 15.0/100 000 for males and 8.0/100 000 for females. Globally, suicide is the second leading cause of death in 15-29 year olds. In a collaborative effort to reduce the high rates of suicide and mental health problems among youth across Europe, the European Union 7th Framework funded the Saving and Empowering Young Lives in Europe (SEYLE) project. SEYLE is a randomized controlled trial (RCT) aimed to promote mental health and healthy lifestyles, while preventing psychopathology and suicidal behaviours among adolescents. The epidemiological data on 11,110 pupils in the age group 14-16 years, with a mean age of 14.8 years (SD ± 0.8), who were recruited from 168 schools across 10 European Union countries: Austria, Estonia, France, Germany, Hungary, Ireland, Italy, Romania, Slovenia and Spain, with Sweden as the coordinating centre showed the following prevalences: alcohol use (13.4%), smoking (30.9%), physical inactivity (32.8%), pathological Internet use (4.4%) and sleeping on average 7.7 hours per night. In terms of reproductive health, the prevalence of sexual debut was 18.8% for the total sample. Pupils aged .16 years had a higher prevalence (38%) of sexual debut compared to those aged .15 years (13.2%). Males had a higher prevalence (21.3%) than females (16.9%). Three clusters of adolescents were identified: 57.8% with low frequency of all risk-behaviours; 13.2% with high frequency of all risk behaviours; and 29% so-called 'invisible' risk group, which did not show any striking externalised riskbehaviours, but scored positive for high use of Internet/TV/videogames, sedentary behaviour and reduced sleep. When comparing pupils in the "invisible" risk group with those in the high-risk group, similar prevalence rates of anxiety (8% vs. 9.2%), subthreshold depression (33.2% vs. 34%), depression (13.4% vs. 14.7%) and suicidal thoughts (42.2% vs. 44%) were observed. Pupils meeting the criteria of depression and subthreshold depression were 10.5% and 32%, respectively. Prevalence rates for anxiety and subthreshold anxiety was 5.8% and 29.2%, respectively. Lifetime prevalence of deliberate self-injurious behaviours (D-SIB) was 27.6%, with higher rates reported for occasional D-SIB (19.7%) compared to repetitive D-SIB (7.8%). Suicidal ideation was present in approximately one third of the sample (32.3%). More than four percent (4.2%) of the sample reported attempting suicide during their lifetime, with a significantly higher prevalence among girls (5.1% vs. 3.0%, p<0.05). In comparing the effectiveness of the three active SEYLE interventions, based on three specific preventive strategies directed towards teachers and school staff, professionals and pupils in comparison to a control group, the intervention empowering pupils, called the Youth Aware of Mental Health (YAM) showed significant results in preventing new cases of suicide attempts, severe suicidal ideation with plans and depression. More than a 50% reduction of incident cases of suicide attempts (OR: 0.45 [0.24 - 0.85]; p=0.014), and of incident cases of severe suicidal ideation and plans (OR: 0.50 [0.27 - 0.92]; p=0.025), as well as a significant reduction by 30% of incident cases with moderate to severe depression (OR: 0.71 [0.52- 0.97]; p=0.031) was observed.

Differential CMOS Sub-Terahertz Detector with Subthreshold Amplifier.

PubMed

Yang, Jong-Ryul; Han, Seong-Tae; Baek, Donghyun

2017-09-09

We propose a differential-type complementary metal-oxide-semiconductor (CMOS) sub-terahertz (THz) detector with a subthreshold preamplifier. The proposed detector improves the voltage responsivity and effective signal-to-noise ratio (SNR) using the subthreshold preamplifier, which is located between the differential detector device and main amplifier. The overall noise of the detector for the THz imaging system is reduced by the preamplifier because it diminishes the noise contribution of the main amplifier. The subthreshold preamplifier is self-biased by the output DC voltage of the detector core and has a dummy structure that cancels the DC offsets generated by the preamplifier itself. The 200 GHz detector fabricated using 0.25 μm CMOS technology includes a low drop-out regulator, current reference blocks, and an integrated antenna. A voltage responsivity of 2020 kV/W and noise equivalent power of 76 pW/√Hz are achieved using the detector at a gate bias of 0.5 V, respectively. The effective SNR at a 103 Hz chopping frequency is 70.9 dB with a 0.7 W/m² input signal power density. The dynamic range of the raster-scanned THz image is 44.59 dB.

Differential CMOS Sub-Terahertz Detector with Subthreshold Amplifier

PubMed Central

Han, Seong-Tae; Baek, Donghyun

2017-01-01

We propose a differential-type complementary metal-oxide-semiconductor (CMOS) sub-terahertz (THz) detector with a subthreshold preamplifier. The proposed detector improves the voltage responsivity and effective signal-to-noise ratio (SNR) using the subthreshold preamplifier, which is located between the differential detector device and main amplifier. The overall noise of the detector for the THz imaging system is reduced by the preamplifier because it diminishes the noise contribution of the main amplifier. The subthreshold preamplifier is self-biased by the output DC voltage of the detector core and has a dummy structure that cancels the DC offsets generated by the preamplifier itself. The 200 GHz detector fabricated using 0.25 μm CMOS technology includes a low drop-out regulator, current reference blocks, and an integrated antenna. A voltage responsivity of 2020 kV/W and noise equivalent power of 76 pW/√Hz are achieved using the detector at a gate bias of 0.5 V, respectively. The effective SNR at a 103 Hz chopping frequency is 70.9 dB with a 0.7 W/m2 input signal power density. The dynamic range of the raster-scanned THz image is 44.59 dB. PMID:28891927

Micropulse laser for persistent optic disc pit maculopathy. A case report.

PubMed

Valdés-Lara, Carlos Andrés; Crim, Nicolás; García-Aguirre, Gerardo; Lule, Ismael Ávila; Morales-Cantón, Virgilio

2018-06-01

Optic disc pits (ODP) are rare and congenital anomalies of the optic disc, sometimes remaining asymptomatic. However, serous macular detachment or optic disc maculopathy is the most common complication, causing significant visual deterioration, without a current consensus about treatment. We describe a case of ODP maculopathy that was treated successfully with micropulse laser. A patient with ODP maculopathy remained with macular serous detachment after nine months of follow up after pars plana vitrectomy. Subthreshold micropulse laser was used to treat macular serous detachment, achieving a significant improvement in central macular thickness after one session. Subthreshold micropulse laser is designed to stimulate the retinal pigment epithelium without damage to the photoreceptors, resulting in absorption of subretinal and intraretinal fluid. Macular serous detachment in patients with ODP requires a prompt diagnosis and treatment to avoid damage to photoreceptors. Subthreshold micropulse laser is a potential treatment for eyes with ODP and macular serous detachment complication.

Rational modulation of neuronal processing with applied electric fields.

PubMed

Bikson, Marom; Radman, Thomas; Datta, Abhishek

2006-01-01

Traditional approaches to electrical stimulation, using trains of supra-threshold pulses to trigger action potentials, may be replaced or augmented by using 'rational' sub-threshold stimulation protocols that incorporate knowledge of single neuron geometry, inhomogeneous tissue properties, and nervous system information coding. Sub-threshold stimulation, at intensities (well) below those sufficient to trigger action potentials, may none-the-less exert a profound effect on brain function through modulation of concomitant neuronal activity. For example, small DC fields may coherently polarize a network of neurons and thus modulate the simultaneous processing of afferent synaptic input as well as resulting changes in synaptic plasticity. Through 'activity-dependent plasticity', sub-threshold fields may allow specific targeting of pathological networks and are thus particularly suitable to overcome the poor anatomical focus of noninvasive (transcranial) electrical stimulation. Additional approaches to improve targeting in transcranial stimulation using novel electrode configurations are also introduced.

Subthreshold depression: characteristics and risk factors among vulnerable elders.

PubMed

Adams, Kathryn Betts; Moon, Heehyul

2009-09-01

This study examines symptoms of subthreshold depression among older adults in congregate housing, compared with their nondepressed peers, and tests a conceptual model of subthreshold depression. Hypotheses included that subthreshold depression would be characterized and distinguished by low energy, social withdrawal, and depletion, rather than sadness, and that subthreshold depressed elders would be distinguished by poorer health and functioning, loneliness, and grieving a recent loss. A self-administered survey was followed by a diagnostic interview by telephone to (N = 166) white and African-American residents of independent and assisted living apartments from six retirement communities, average age 82.9 years. The Mini International Neuropsychiatric Interview (MINI) determined depression status. The 30-item Geriatric Depression Scale was used to measure symptoms. Forty-six individuals (27.7%) were identified as subthreshold depressed, seven as suffering from major depression, and 113 as non-depressed. Subthreshold depression was characterized by low energy, difficulty with initiative, worries about the future, lack of positive affect, sadness and irritability. Negative affect symptoms such as sadness and irritability best discriminated the subthreshold group from the nondepressed. Risk factors for subthreshold depression in this sample included less education, lower socio-economic status, African-American race, grieving, and social loneliness. Subthreshold depression in this group of residents of congregate housing was similar to the depletion experienced by many nondepressed elders, but further characterized by negative affect and lack of hope for the future. Social factors, such as socioeconomic status and personal losses, constituted greater risks for subthreshold depression than did health and functioning.

In vivo mouse inferior olive neurons exhibit heterogeneous subthreshold oscillations and spiking patterns

PubMed Central

Khosrovani, S.; Van Der Giessen, R. S.; De Zeeuw, C. I.; De Jeu, M. T. G.

2007-01-01

In vitro whole-cell recordings of the inferior olive have demonstrated that its neurons are electrotonically coupled and have a tendency to oscillate. However, it remains to be shown to what extent subthreshold oscillations do indeed occur in the inferior olive in vivo and whether its spatiotemporal firing pattern may be dynamically generated by including or excluding different types of oscillatory neurons. Here, we did whole-cell recordings of olivary neurons in vivo to investigate the relation between their subthreshold activities and their spiking behavior in an intact brain. The vast majority of neurons (85%) showed subthreshold oscillatory activities. The frequencies of these subthreshold oscillations were used to distinguish four main olivary subtypes by statistical means. Type I showed both sinusoidal subthreshold oscillations (SSTOs) and low-threshold Ca2+ oscillations (LTOs) (16%); type II showed only sinusoidal subthreshold oscillations (13%); type III showed only low-threshold Ca2+ oscillations (56%); and type IV did not reveal any subthreshold oscillations (15%). These subthreshold oscillation frequencies were strongly correlated with the frequencies of preferred spiking. The frequency characteristics of the subthreshold oscillations and spiking behavior of virtually all olivary neurons were stable throughout the recordings. However, the occurrence of spontaneous or evoked action potentials modified the subthreshold oscillation by resetting the phase of its peak toward 90°. Together, these findings indicate that the inferior olive in intact mammals offers a rich repertoire of different neurons with relatively stable frequency settings, which can be used to generate and reset temporal firing patterns in a dynamically coupled ensemble. PMID:17895389

Oral contraceptive use and psychiatric disorders in a nationally representative sample of women.

PubMed

Cheslack-Postava, Keely; Keyes, Katherine M; Lowe, Sarah R; Koenen, Karestan C

2015-02-01

The purpose of this study is to examine the association between oral contraceptive use (any current use, duration, and type) and major depressive disorder (MDD), generalized anxiety disorder (GAD), and panic disorder (PD) in a nationally representative sample of women in the USA. Data were drawn from 1,105 women aged 20-39 in the National Health and Nutrition Examination Surveys from 1999 to 2004. The associations between self-reported use of oral contraceptives in the past year and DSM-IV diagnosed and subthreshold MDD, GAD, and PD in the past year were assessed comparing oral contraceptive users to all non-users, former users, and former long-term users. Women using oral contraceptives had a lower past-year prevalence of all disorders assessed, other than subthreshold MDD. When adjusted for confounders, women using oral contraceptives in the past year had significantly lower odds of subthreshold PD, compared to former users (odds ratio (OR) = 0.34, 95 % CI 0.14-0.84). Effects estimates were strongest for monophasic (versus multiphasic) oral contraceptive users. Hormonal contraceptive use was associated with reduced risk of subthreshold PD. A potential mental health benefit of hormonal contraceptives has substantial public health implications; prospective longitudinal studies are needed to confirm whether hormonal contraceptive use improves mental health.

The Effects of Subthreshold Visual Cues on Flight Performance in the NUH-60FS Black Hawk Research Simulator

DTIC Science & Technology

2011-08-01

influenced your opinion of subthreshold priming/ subliminal messaging...17 10. After completing this experiment, do you have a positive or negative view of subthreshold priming/ subliminal ...0%) Table 9. Has participating in this experiment influenced your opinion of subthreshold priming/ subliminal messaging? Yes No Other

Modulation of spike coding by subthreshold extracellular electric fields and neuronal morphology

NASA Astrophysics Data System (ADS)

Wei, Xile; Li, Bingjie; Lu, Meili; Yi, Guosheng; Wang, Jiang

2015-07-01

We use a two-compartment model, which includes soma and dendrite, to explore how extracellular subthreshold sinusoidal electric fields (EFs) influence the spike coding of an active neuron. By changing the intensity and the frequency of subthreshold EFs, we find that subthreshold EFs indeed affect neuronal coding remarkably within several stimulus frequency windows where the field effects on spike timing are stronger than that on spiking rate. The field effects are maximized at several harmonics of the intrinsic spiking frequency of an active neuron. Our findings implicate the potential resonance mechanism underlying subthreshold field effects. We also discuss how neuronal morphologic properties constrain subthreshold EF effects on spike timing. The morphologic properties are represented by two parameters, gc and p, where gc is the internal conductance between soma and dendrite and geometric factor p characterizes the proportion of area occupied by soma. We find that the contribution to field effects from the variation of p is stronger than that from gc, which suggests that neuronal geometric features play a crucial role in subthreshold field effects. Theoretically, these insights into how subthreshold sinusoidal EFs modulate ongoing neuron behaviors could contribute to uncovering the relevant mechanism of subthreshold sinusoidal EFs effects on neuronal coding. Furthermore, they are useful in rationally designing noninvasive brain stimulation strategies and developing electromagnetic stimulus techniques.

Subthreshold Conditions as Precursors for Full Syndrome Disorders: A 15-Year Longitudinal Study of Multiple Diagnostic Classes

ERIC Educational Resources Information Center

Shankman, Stewart A.; Lewinsohn, Peter M.; Klein, Daniel N.; Small, Jason W.; Seeley, John R.; Altman, Sarah E.

2009-01-01

Background: There has been increasing interest in the distinction between subthreshold and full syndrome disorders and specifically whether subthreshold conditions escalate or predict the onset of full syndrome disorders over time. Most of these studies, however, examined whether a single subthreshold condition escalates into the full syndrome…

Adolescent THC exposure does not sensitize conditioned place preferences to subthreshold d-amphetamine in male and female rats.

PubMed

Keeley, Robin J; Bye, Cameron; Trow, Jan; McDonald, Robert J

2018-01-01

The acute effects of marijuana consumption on brain physiology and behaviour are well documented, but the long-term effects of its chronic use are less well known. Chronic marijuana use during adolescence is of increased interest, given that the majority of individuals first use marijuana during this developmental stage , and  adolescent marijuana use is thought to increase the susceptibility to abusing other drugs when exposed later in life. It is possible that marijuana use during critical periods in adolescence could lead to increased sensitivity to other drugs of abuse later on. To test this, we chronically administered ∆ 9 -tetrahydrocannabinol (THC) to male and female Long-Evans (LER) and Wistar (WR) rats directly after puberty onset. Rats matured to postnatal day 90 before being exposed to a conditioned place preference task (CPP). A subthreshold dose of d-amphetamine, found not to induce place preference in drug naïve rats, was used as the unconditioned stimulus. The effect of d-amphetamine on neural activity was inferred by quantifying cfos expression in the nucleus accumbens and dorsal hippocampus following CPP training. Chronic exposure to THC post-puberty had no potentiating effect on a subthreshold dose of d-amphetamine to induce CPP. No differences in cfos expression were observed. These results show that chronic exposure to THC during puberty did not increase sensitivity to d-amphetamine in adult LER and WR rats. This supports the concept that THC may not sensitize the response to all drugs of abuse.

Cognitive-behavioral therapy for subthreshold bulimia nervosa: A case series.

PubMed

Peterson, C B; Miller, K B; Willer, M G; Ziesmer, J; Durkin, N; Arikian, A; Crow, S J

2011-09-01

The extent to which cognitive-behavioral therapy (CBT) is helpful in treating individuals with bulimic symptoms who do not meet full criteria for bulimia nervosa is unclear. The purpose of this investigation was to examine the potential efficacy of CBT for eating disorder individuals with bulimic symptoms who do not meet full criteria for bulimia nervosa. Twelve participants with subthreshold bulimia nervosa were treated in a case series with 20 sessions of CBT. Ten of the 12 participants (83.3%) completed treatment. Intent-to-treat abstinent percentages were 75.0% for objectively large episodes of binge eating (OBEs), 33.3% for subjectively large episodes of binge eating (SBEs), and 50% for purging at end of treatment. At one year follow-up, 66.7% were abstinent for OBEs, 41.7% for SBEs, and 50.0% for purging. The majority also reported improvements in associated symptoms. This case series provides support for the use of CBT with individuals with subthreshold bulimia nervosa.

Subthreshold diode laser micropulse photocoagulation for the treatment of diabetic macular edema.

PubMed

Sivaprasad, Sobha; Dorin, Giorgio

2012-03-01

Diabetic macular edema (DME) is a sight-threatening complication of diabetic retinopathy, the leading cause of visual loss in the working-age population in the industrialized and emerging world. The standard of care for DME is focal/grid laser photocoagulation, which is proven effective in reducing the risk of vision loss, but inherently destructive and associated with tissue damage and collateral effects. Subthreshold diode laser micropulse photocoagulation is a nondestructive tissue-sparing laser procedure, which, in randomized controlled trials for the treatment of DME, has been found equally effective as conventional photocoagulation. Functional and anatomical outcomes from four independent randomized controlled trials provide level one evidence that vision stabilization/improvement and edema resolution/reduction can be elicited with less or no retinal damage, and with fewer or no complications. This review describes the principles of subthreshold diode laser micropulse photocoagulation, its treatment modalities and clinical outcomes in the context of standard laser treatments and of emerging nonlaser therapies for DME.

Partial blockade of Kv2.1 channel potentiates GLP-1's insulinotropic effects in islets and reduces its dose required for improving glucose tolerance in type 2 diabetic male mice.

PubMed

Sukma Rita, Rauza; Dezaki, Katsuya; Kurashina, Tomoyuki; Kakei, Masafumi; Yada, Toshihiko

2015-01-01

Glucagon-like peptide-1 (GLP-1)-based medicines have recently been widely used to treat type 2 diabetic patients, whereas adverse effects of nausea and vomiting have been documented. Inhibition of voltage-gated K(+) channel subtype Kv2.1 in pancreatic β-cells has been suggested to contribute to mild depolarization and promotion of insulin release. This study aimed to determine whether the blockade of Kv2.1 channels potentiates the insulinotropic effect of GLP-1 agonists. Kv2.1 channel blocker guangxitoxin-1E (GxTx) and GLP-1 agonist exendin-4 at subthreshold concentrations, when combined, markedly increased the insulin release and cytosolic Ca(2+) concentration ([Ca(2+)]i) in a glucose-dependent manner in mouse islets and β-cells. Exendin-4 at subthreshold concentration alone increased islet insulin release and β-cell [Ca(2+)]i in Kv2.1(+/-) mice. The [Ca(2+)]i response to subthreshold exendin-4 and GxTx in combination was attenuated by pretreatment with protein kinase A inhibitor H-89, indicating the protein kinase A dependency of the cooperative effect. Furthermore, subthreshold doses of GxTx and GLP-1 agonist liraglutide in combination markedly increased plasma insulin and improved glucose tolerance in diabetic db/db mice and NSY mice. These results demonstrate that a modest suppression of Kv2.1 channels dramatically raises insulinotropic potency of GLP-1-based drugs, which opens a new avenue to reduce their doses and associated adverse effects while achieving the same glycemic control in type 2 diabetes.

Activation of Ih and TTX-sensitive sodium current at subthreshold voltages during CA1 pyramidal neuron firing

PubMed Central

Yamada-Hanff, Jason

2015-01-01

We used dynamic clamp and action potential clamp techniques to explore how currents carried by tetrodotoxin-sensitive sodium channels and HCN channels (Ih) regulate the behavior of CA1 pyramidal neurons at resting and subthreshold voltages. Recording from rat CA1 pyramidal neurons in hippocampal slices, we found that the apparent input resistance and membrane time constant were strongly affected by both conductances, with Ih acting to decrease apparent input resistance and time constant and sodium current acting to increase both. We found that both Ih and sodium current were active during subthreshold summation of artificial excitatory postsynaptic potentials (EPSPs) generated by dynamic clamp, with Ih dominating at less depolarized voltages and sodium current at more depolarized voltages. Subthreshold sodium current—which amplifies EPSPs—was most effectively recruited by rapid voltage changes, while Ih—which blunts EPSPs—was maximal for slow voltage changes. The combined effect is to selectively amplify rapid EPSPs. We did similar experiments in mouse CA1 pyramidal neurons, doing voltage-clamp experiments using experimental records of action potential firing of CA1 neurons previously recorded in awake, behaving animals as command voltages to quantify flow of Ih and sodium current at subthreshold voltages. Subthreshold sodium current was larger and subthreshold Ih was smaller in mouse neurons than in rat neurons. Overall, the results show opposing effects of subthreshold sodium current and Ih in regulating subthreshold behavior of CA1 neurons, with subthreshold sodium current prominent in both rat and mouse CA1 pyramidal neurons and additional regulation by Ih in rat neurons. PMID:26289465

Effect of low doses of cannabidiolic acid and ondansetron on LiCl-induced conditioned gaping (a model of nausea-induced behaviour) in rats

PubMed Central

Rock, EM; Parker, LA

2013-01-01

Background and Purpose To determine the minimally effective dose of cannabidiolic acid (CBDA) that effectively reduces lithium chloride (LiCl)-induced conditioned gaping reactions (nausea-induced behaviour) in rats and to determine if these low systemic doses of CBDA (5–0.1 μg·kg−1) relative to those of CBD could potentiate the anti-nausea effects of the classic 5-hydroxytryptamine 3 (5-HT3) receptor antagonist, ondansetron (OND). Experimental Approach We investigated the efficacy of low doses of CBDA to suppress acute nausea, assessed by the establishment of conditioned gaping to a LiCl-paired flavour in rats. The potential of threshold and subthreshold doses of CBDA to enhance the reduction of nausea-induced conditioned gaping by OND were then determined. Key Results CBDA (at doses as low as 0.5 μg·kg−1) suppressed nausea-induced conditioned gaping to a flavour. A low dose of OND (1.0 μg·kg−1) alone reduced nausea-induced conditioned gaping, but when it was combined with a subthreshold dose of CBDA (0.1 μg·kg−1) there was an enhancement in the suppression of LiCl-induced conditioned gaping. Conclusions and Implications CBDA potently reduced conditioned gaping in rats, even at low doses and enhanced the anti-nausea effect of a low dose of OND. These findings suggest that combining low doses of CBDA and OND will more effectively treat acute nausea in chemotherapy patients. PMID:23488964

Effect of low doses of cannabidiolic acid and ondansetron on LiCl-induced conditioned gaping (a model of nausea-induced behaviour) in rats.

PubMed

Rock, E M; Parker, L A

2013-06-01

To determine the minimally effective dose of cannabidiolic acid (CBDA) that effectively reduces lithium chloride (LiCl)-induced conditioned gaping reactions (nausea-induced behaviour) in rats and to determine if these low systemic doses of CBDA (5-0.1 μg·kg⁻¹) relative to those of CBD could potentiate the anti-nausea effects of the classic 5-hydroxytryptamine 3 (5-HT₃) receptor antagonist, ondansetron (OND). We investigated the efficacy of low doses of CBDA to suppress acute nausea, assessed by the establishment of conditioned gaping to a LiCl-paired flavour in rats. The potential of threshold and subthreshold doses of CBDA to enhance the reduction of nausea-induced conditioned gaping by OND were then determined. CBDA (at doses as low as 0.5 μg·kg⁻¹) suppressed nausea-induced conditioned gaping to a flavour. A low dose of OND (1.0 μg·kg⁻¹) alone reduced nausea-induced conditioned gaping, but when it was combined with a subthreshold dose of CBDA (0.1 μg·kg⁻¹) there was an enhancement in the suppression of LiCl-induced conditioned gaping. CBDA potently reduced conditioned gaping in rats, even at low doses and enhanced the anti-nausea effect of a low dose of OND. These findings suggest that combining low doses of CBDA and OND will more effectively treat acute nausea in chemotherapy patients. © 2013 The Authors. British Journal of Pharmacology © 2013 The British Pharmacological Society.

Paresthesia-Free High-Density Spinal Cord Stimulation for Postlaminectomy Syndrome in a Prescreened Population: A Prospective Case Series.

PubMed

Sweet, Jennifer; Badjatiya, Anish; Tan, Daniel; Miller, Jonathan

2016-04-01

Spinal cord stimulation (SCS) traditionally is thought to require paresthesia, but there is evidence that paresthesia-free stimulation using high-density (HD) parameters might also be effective. The purpose of this study is to evaluate relative effectiveness of conventional, subthreshold HD, and sham stimulation on pain intensity and quality of life. Fifteen patients with response to conventional stimulation (60 Hz/350 μsec) were screened with a one-week trial of subthreshold HD (1200 Hz/200 μsec/amplitude 90% paresthesia threshold) and enrolled if there was at least 50% reduction on visual analog scale (VAS) for pain. Subjects were randomized into two groups and treated with four two-week periods of conventional, subthreshold HD, and sham stimulation in a randomized crossover design. Four of 15 patients responded to subthreshold HD stimulation. Mean VAS during conventional, subthreshold HD, and sham stimulation was 5.32 ± 0.63, 2.29 ± 0.41, and 6.31 ± 1.22, respectively. There was a significant difference in pain scores during the blinded crossover study of subthreshold HD vs. sham stimulation (p < 0.05, Student's t-test). Post hoc analysis revealed that subjects reported significantly greater attention to pain during conventional stimulation compared with subthreshold HD stimulation (p < 0.05, Student's t-test). All subjects reported a positive impression of change for subthreshold HD stimulation compared with conventional stimulation, and there was a trend toward greater likelihood for response to subthreshold HD stimulation in comparison with sham stimulation (p = 0.07, Fisher's exact test). At the end of the trial, all subjects elected to continue to receive subthreshold HD stimulation rather than conventional stimulation. Paresthesia are not necessary for pain relief using commercially available SCS devices, and may actually increase attention to pain. Subthreshold HD SCS represents a viable alternative to conventional stimulation among patients who are confirmed to have a clinical response to it. © 2015 International Neuromodulation Society.

Subthreshold posttraumatic stress disorder: A meta-analytic review of DSM-IV prevalence and a proposed DSM-5 approach to measurement.

PubMed

Brancu, Mira; Mann-Wrobel, Monica; Beckham, Jean C; Wagner, H Ryan; Elliott, Alyssa; Robbins, Allison T; Wong, Madrianne; Berchuck, Ania E; Runnals, Jennifer J

2016-03-01

Subthreshold posttraumatic stress disorder (PTSD) is a chronic condition that is often ignored, the cumulative effects of which can negatively impact an individual's quality of life and overall health care costs. However, subthreshold PTSD prevalence rates and impairment remain unclear due to variations in research methodology. This study examined the existing literature in order to recommend approaches to standardize subthreshold PTSD assessment. We conducted (a) a meta-analysis of subthreshold PTSD prevalence rates and (b) compared functional impairment associated with the 3 most commonly studied subthreshold PTSD definitions. Meta-analytic results revealed that the average prevalence rate of subthreshold PTSD across studies was 14.7%, with a lower rate (12.6%) among the most methodologically rigorous studies and higher rate (15.6%) across less rigorous studies. There were significant methodological differences among reviewed studies with regard to definition, measurement, and population. Different definitions led to prevalence rates ranging between 13.7% and 16.4%. Variability in prevalence rates most related to population and sample composition, with trauma type and community (vs. epidemiological) samples significantly impacting heterogeneity. Qualitative information gathered from studies presenting functional correlates supported current evidence that psychological and behavioral parameters were worse among subthreshold PTSD groups compared with no-PTSD groups, but not as severe as impairment in PTSD groups. Several studies also reported significant increased risk of suicidality and hopelessness as well as higher health care utilization rates among those with subthreshold PTSD (compared with trauma exposed no-PTSD samples). Based on findings, we propose recommendations for developing a standard approach to evaluation of subthreshold PTSD. (c) 2016 APA, all rights reserved).

Subthreshold body dysmorphic disorder in adolescents: Prevalence and impact.

PubMed

Schneider, Sophie C; Mond, Jonathan; Turner, Cynthia M; Hudson, Jennifer L

2017-05-01

The aim of the current study was to establish the prevalence of subthreshold body dysmorphic disorder (subthreshold-BDD) in a community sample of adolescents, and to compare disorder correlates in individuals with subthreshold-BDD to those with probable full-syndrome BDD (probable-BDD) and those without BDD (non-BDD). Self-report questionnaires assessing DSM-IV BDD criteria, past mental health service use, and symptoms of body dysmorphic disorder, anxiety, depression, obsessive-compulsive disorder and eating disorders, were completed by 3149 Australian high school students (mean age =14.6 years, 63.5% male). Male participants also completed measures assessing quality of life, muscularity concerns, emotional symptoms, conduct problems, hyperactivity, and peer problems. The prevalence of subthreshold-BDD was 3.4%, and probable-BDD was 1.7%. Compared to the non-BDD group, subthreshold-BDD was associated with elevated symptoms of comorbid psychopathology and greater past mental health service use, and in male-only measures, with poorer quality of life and elevated muscularity concerns. Subthreshold-BDD participants reported significantly lower mental health service use, and fewer symptoms of depression, eating disorders, and hyperactivity than probable-BDD participants, however, other comorbid symptoms did not differ significantly between these groups. These findings indicate that subthreshold-BDD is associated with substantial difficulties for adolescents in the general community. BDD screening should include subthreshold presentations, as these may be an important target for early intervention programs. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Dependence of interface charge trapping on channel engineering in pentacene field effect transistors.

PubMed

Lee, Sunwoo; Park, Junghyuck; Park, In-Sung; Ahn, Jinho

2014-07-01

We investigate the dependence of charge carrier mobility by trap states at various interface regions through channel engineering. Prior to evaluation of interface trap density, the electrical performance in pentaene field effect transistors (FET) with high-k gate oxide are also investigated depending on four channel engineering. As a channel engineering, gas treatment, coatings of thin polymer layer, and chemical surface modification using small molecules were carried out. After channel engineering, the performance of device as well as interface trap density calculated by conductance method are remarkably improved. It is found that the reduced interface trap density is closely related to decreasing the sub-threshold swing and improving the mobility. Particularly, we also found that performance of device such as mobility, subthreshold swing, and interface trap density after gas same is comparable to those of OTS.

Efficacy and moderators of psychological interventions in treating subclinical symptoms of depression and preventing major depressive disorder onsets: protocol for an individual patient data meta-analysis of randomised controlled trials

PubMed Central

Reins, Jo Annika; Zimmermann, Johannes; Cuijpers, Pim

2018-01-01

Introduction The long-term effectiveness of psychological interventions for the treatment of subthreshold depression and the prevention of depression is unclear and effects vary among subgroups of patients, indicating that not all patients profit from such interventions. Randomised clinical trials are mostly underpowered to examine adequately subgroups and moderator effects. The aim of the present study is, therefore, to examine the short-term and long-term as well as moderator effects of psychological interventions compared with control groups in adults with subthreshold depression on depressive symptom severity, treatment response, remission, symptom deterioration, quality of life, anxiety and the prevention of major depressive disorder (MDD) onsets on individual patient level and study level using an individual patient data meta-analysis approach. Methods and analysis Systematic searches in PubMed, PsycINFO, Embase and the Cochrane Central Register of Controlled Trials were conducted. We will use the following types of outcome criteria: (A) onset of major depression; (B) time to major depression onset; (C) observer-reported and self-reported depressive symptom severity; (D) response; (E) remission; (F) symptom deterioration; (G) quality of life, (H) anxiety; and (I) suicidal thoughts and behaviours. Multilevel models with participants nested within studies will be used. Missing data will be handled using a joint modelling approach to multiple imputation. A number of sensitivity analyses will be conducted in order test the robustness of our findings. Ethics and dissemination The investigators of the primary trials have obtained ethical approval for the data used in the present study and for sharing the data, if this was necessary, according to local requirements and was not covered from the initial ethic assessment. This study will summarise the available evidence on the short-term and long-term effectiveness of preventive psychological interventions for the treatment of subthreshold depression and prevention of MDD onset. Identification of subgroups of patients in which those interventions are most effective will guide the development of evidence-based personalised interventions for patients with subthreshold depression. PROSPERO registration number CRD42017058585. PMID:29549201

Transient sodium current at subthreshold voltages: activation by EPSP waveforms

PubMed Central

Carter, Brett C.; Giessel, Andrew J.; Sabatini, Bernardo L.; Bean, Bruce P.

2012-01-01

Summary Tetrodotoxin (TTX)-sensitive sodium channels carry large transient currents during action potentials and also “persistent” sodium current, a non-inactivating TTX-sensitive current present at subthreshold voltages. We examined gating of subthreshold sodium current in dissociated cerebellar Purkinje neurons and hippocampal CA1 neurons, studied at 37 °C with near-physiological ionic conditions. Unexpectedly, in both cell types small voltage steps at subthreshold voltages activated a substantial component of transient sodium current as well as persistent current. Subthreshold EPSP-like waveforms also activated a large component of transient sodium current, but IPSP-like waveforms engaged primarily persistent sodium current with only a small additional transient component. Activation of transient as well as persistent sodium current at subthreshold voltages produces amplification of EPSPs that is sensitive to the rate of depolarization and can help account for the dependence of spike threshold on depolarization rate, as previously observed in vivo. PMID:22998875

Exergames vs. traditional exercise: investigating the influencing mechanism of platform effect on subthreshold depression among older adults.

PubMed

Li, Jinhui; Theng, Yin-Leng; Foo, Schubert; Xu, Xuexin

2017-10-06

This study aimed to examine the influencing mechanism of exercise platform effect on subthreshold depression among older adults by comparing exergames and traditional exercise. One hundred and two Singaporean older adults were assigned to either playing Wii exergames or performing traditional exercise programs once a week, for six weeks. Results confirmed a direct negative platform effect on subthreshold depression and further supported the mediation role of positive emotions in the platform effect. It implied that exergames led to higher positive emotions than traditional exercise, which further reduced the subthreshold depression among older adults. Self-efficacy was not supported to be a significant mediator in the relations between exercise platform and subthreshold depression. A better understanding of the mechanisms behind the antidepressant effects of exercise platform would not only provide additional insight into a possible causal association, but also inspire the future use of exergames in the treatment of subthreshold depression.

Mixed anxiety depression should not be included in DSM-5.

PubMed

Batelaan, Neeltje M; Spijker, Jan; de Graaf, Ron; Cuijpers, Pim

2012-06-01

Subthreshold anxiety and subthreshold depressive symptoms often co-occur in the general population and in primary care. Based on their associated significant distress and impairment, a psychiatric classification seems justified. To enable classification, mixed anxiety depression (MAD) has been proposed as a new diagnostic category in DSM-5. In this report, we discuss arguments against the classification of MAD. More research is needed before reifying a new category we know so little about. Moreover, we argue that in patients with MAD symptoms and a history of an anxiety or depressive disorder, symptoms should be labeled as part of the course trajectories of these disorders, rather than calling it a different diagnostic entity. In patients with incident co-occurring subthreshold anxiety and subthreshold depression, subthreshold categories of both anxiety and depression could be classified to maintain a consistent classification system at both threshold and subthreshold levels.

A qualitative analysis of aspects of treatment that adolescents with anorexia identify as helpful.

PubMed

Zaitsoff, Shannon; Pullmer, Rachelle; Menna, Rosanne; Geller, Josie

2016-04-30

This study aimed to identify aspects of treatment that adolescents with anorexia nervosa (AN) believe are helpful or unhelpful. Adolescent females receiving treatment for AN or subthreshold AN (n=21) were prompted during semi-structured interviews to generate responses to open-ended questions on what they felt would be most helpful or unhelpful in treating adolescents with eating disorders. Eight codes were developed and the two most frequently endorsed categories were (1) Alliance, where the therapist demonstrates clinical expertise and also expresses interest in the patient (n=21, 100.0%), and (2) Client Involvement in treatment (n=16, 76.2%). These top two categories were shared by participants with AN versus subthreshold AN and participants with high versus low readiness to change their dietary restriction behaviours. Development of the coding scheme and sample participant responses will be discussed. The integration of identified factors into empirically supported treatments for adolescent AN, such as Family-based Treatment, will be considered. This study provides initial information regarding aspects of treatment that adolescents identify as most helpful or unhelpful in their treatment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Improvement in top-gate MoS2 transistor performance due to high quality backside Al2O3 layer

NASA Astrophysics Data System (ADS)

Bolshakov, Pavel; Zhao, Peng; Azcatl, Angelica; Hurley, Paul K.; Wallace, Robert M.; Young, Chadwin D.

2017-07-01

A high quality Al2O3 layer is developed to achieve high performance in top-gate MoS2 transistors. Compared with top-gate MoS2 field effect transistors on a SiO2 layer, the intrinsic mobility and subthreshold slope were greatly improved in high-k backside layer devices. A forming gas anneal is found to enhance device performance due to a reduction in the charge trap density of the backside dielectric. The major improvements in device performance are ascribed to the forming gas anneal and the high-k dielectric screening effect of the backside Al2O3 layer. Top-gate devices built upon these stacks exhibit a near-ideal subthreshold slope of ˜69 mV/dec and a high Y-Function extracted intrinsic carrier mobility (μo) of 145 cm2/V.s, indicating a positive influence on top-gate device performance even without any backside bias.

Analysis of switching characteristics for negative capacitance ultra-thin-body germanium-on-insulator MOSFETs

NASA Astrophysics Data System (ADS)

Pi-Ho Hu, Vita; Chiu, Pin-Chieh

2018-04-01

The impact of device parameters on the switching characteristics of negative capacitance ultra-thin-body (UTB) germanium-on-insulator (NC-GeOI) MOSFETs is analyzed. NC-GeOI MOSFETs with smaller gate length (L g), EOT, and buried oxide thickness (T box) and thicker ferroelectric layer thickness (T FE) exhibit larger subthreshold swing improvements over GeOI MOSFETs due to better capacitance matching. Compared with GeOI MOSFETs, NC-GeOI MOSFETs exhibit better switching time due to improvements in effective drive current (I eff) and subthreshold swing. NC-GeOI MOSFET exhibits larger ST improvements at V dd = 0.3 V (-82.9%) than at V dd = 0.86 V (-9.7%), because NC-GeOI MOSFET shows 18.2 times higher I eff than the GeOI MOSFET at V dd = 0.3 V, while 2.5 times higher I eff at V dd = 0.86 V. This work provides the device design guideline of NC-GeOI MOSFETs for ultra-low power applications.

Full syndrome and subthreshold attention-deficit/hyperactivity disorder in a Korean community sample: comorbidity and temperament findings.

PubMed

Cho, Soo-Churl; Kim, Boong-Nyun; Kim, Jae-Won; Rohde, Luis Augusto; Hwang, Jun-Won; Chungh, Dong-Seon; Shin, Min-Sup; Lyoo, In Kyoon; Go, Bock-Ja; Lee, Sang-Eun; Kim, Hyo-Won

2009-07-01

The main objective of this study was to investigate the comorbid disorders and temperamental profiles of full syndrome and subthreshold attention-deficit/hyperactivity disorder (ADHD). A sample of 2,493 students was randomly selected from six representative elementary schools in Seoul, Korea. Among 245 children with full syndrome and subthreshold ADHD diagnosed by the diagnostic interview schedule for children-4th version, parents of 185 subjects (mean age 9.0 +/- 1.7 years) and of a random sample of 185 age- and gender-matched non-ADHD children have completed the parent's version of the children behavior checklist (CBCL) and the juvenile temperament and character inventory (JTCI). The prevalence rates of full syndrome and subthreshold ADHD were, respectively, 5.90% (95% confidence interval = 4.74-7.06) and 9.00% (95% confidence interval = 7.58-10.41). Subthreshold ADHD cases did not differ from full syndrome ADHD in any JTCI profile, showing high novelty seeking/low persistence/low self-directedness than controls. Subthreshold ADHD also showed increased risk for externalizing disorders and higher scores in eight CBCL scales (somatic complaints, anxious/depressed, social problems, attention problems, delinquent behaviors, aggressive behaviors, externalizing problems and total behavioral problems) compared to the controls. These results support the clinical relevance of subthreshold ADHD in Asian culture. Increased clinical awareness for children with subthreshold ADHD is needed.

A Tune in “A Minor” Can “B Major”: A Review of Epidemiology, Illness Course, and Public Health Implications of Subthreshold Depression in Older Adults

PubMed Central

Meeks, Thomas; Vahia, Ipsit; Lavretsky, Helen; Kulkarni, Ganesh; Jeste, Dilip

2010-01-01

BACKGROUND With emphasis on dimensional aspects of psychopathology in development of the upcoming DSM-V, we systematically review data on epidemiology, illness course, risk factors for, and consequences of late-life depressive syndromes not meeting DSM-IV-TR criteria for major depression or dysthymia. We termed these syndromes subthreshold depression, including minor depression and subsyndromal depression. METHODS We searched PubMed (1980–Jan 2010) using the terms: subsyndromal depression, subthreshold depression, and minor depression in combination with elderly, geriatric, older adult, and late-life. Data were extracted from 181 studies of late-life subthreshold depression. RESULTS In older adults subthreshold depression was generally at least 2–3 times more prevalent (median community point prevalence 9.8%) than major depression. Prevalence of subthreshold depression was lower in community settings versus primary care and highest in long-term care settings. Approximately 8–10% of older persons with subthreshold depression developed major depression per year. The course of late-life subthreshold depression was more favorable than that of late-life major depression, but far from benign, with a median remission rate to non-depressed status of only 27% after ≥1 year. Prominent risk factors included female gender, medical burden, disability, and low social support; consequences included increased disability, greater healthcare utilization, and increased suicidal ideation. LIMITATIONS Heterogeneity of the data, especially related to definitions of subthreshold depression limit our ability to conduct meta-analysis. CONCLUSIONS The high prevalence and associated adverse health outcomes of late-life subthreshold depression indicate the major public health significance of this condition and suggest a need for further research on its neurobiology and treatment. Such efforts could potentially lead to prevention of considerable morbidity for the growing number of older adults. PMID:20926139

LASER RESENSITIZATION OF MEDICALLY UNRESPONSIVE NEOVASCULAR AGE-RELATED MACULAR DEGENERATION: Efficacy and Implications.

PubMed

Luttrull, Jeffrey K; Chang, David B; Margolis, Benjamin W L; Dorin, Giorgio; Luttrull, David K

2015-06-01

Drug tolerance is the most common cause of treatment failure in neovascular age-related macular degeneration. "Low-intensity/high-density" subthreshold diode micropulse laser (SDM) has been reported effective for a number of retinal disorders without adverse effects. It has been proposed that SDM normalizes retinal pigment epithelial function. On this basis, it has been postulated that SDM treatment might restore responsiveness to anti-vascular endothelial growth factor drugs in drug-tolerant eyes. Subthreshold diode micropulse laser treatment was performed in consecutive eyes unresponsive to all anti-vascular endothelial growth factor drugs, including at least three consecutive ineffective aflibercept injections. Monthly aflibercept was resumed 1 month after SDM treatment. Thirteen eyes of 12 patients, aged 73 to 97 years (average, 84 years), receiving 16 to 67 (average, 34) anti-vascular endothelial growth factor injections before SDM treatment were included and followed for 3 months to 7 months (average, 5 months) after SDM treatment. After SDM treatment and resumption of aflibercept, 92% (12 of 13) of eyes improved, with complete resolution of macular exudation in 69% (9 of 13). Visual acuity remained unchanged. Central and maximum macular thicknesses significantly improved. Subthreshold diode micropulse laser treatment restored drug response in drug-tolerant eyes with neovascular age-related macular degeneration. Based on these findings, a theory of SDM action is proposed, suggesting a wider role for SDM as retinal reparative/protective therapy.

Survey of premenstrual symptom severity and impairment in Korean adolescents: premenstrual dysphoric disorder, subthreshold premenstrual dysphoric disorder and premenstrual syndrome.

PubMed

Yang, Jaewon; Joe, Sook-Haeng; Lee, Moon-Soo; Kim, Seung-Hyun; Jung, In-Kwa

2014-06-01

The aims of the study were to examine the prevalence of premenstrual dysphoric disorder (PMDD), subthreshold PMDD and premenstrual syndrome (PMS) among adolescents, and to assess the nature of symptoms and the impact on daily life functions, especially for PMDD and subthreshold PMDD. A cross-sectional survey was conducted among adolescents from an urban area. Participants included 984 girls divided into the following four groups, using a premenstrual symptoms screening tool: PMDD, subthreshold PMDD, moderate/severe PMS and no/mild PMS. An Adolescent Mental Problem Questionnaire, Center for Epidemiological Studies-Depression Scale, revised Children's Manifest Anxiety Scale, and a menstrual information questionnaire were also used. Sixty-three (6.76%) of the subjects met the criteria for PMDD and 58 (6.2%) were subthreshold PMDD. The subthreshold PMDD group included 79.3% who met the symptom criteria for PMDD, but their impairment was moderate, and 21.7% who were falling short by the number of symptoms for PMDD diagnosis, though reporting severe impairment. The symptom intensity and frequency of the subthreshold PMDD subjects were similar to those in subjects with PMDD. In these two groups, 69% had moderate to severe physical symptoms. Psychiatric problems, including depression and anxiety, were higher in the PMDD and subthreshold PMDD groups than in the moderate/severe PMS and no/mild PMS group. In total, 20% of adolescents reported suffering from distressing premenstrual symptoms, and girls with PMDD and subthreshold PMDD were very similar in their symptom severity and characteristics. Prospective daily charting is needed to confirm the accurate diagnosis and management of PMDD. Copyright © 2012 Wiley Publishing Asia Pty Ltd.

Detection of sub-threshold periodic signal by multiplicative and additive cross-correlated sine-Wiener noises in the FitzHugh-Nagumo neuron

NASA Astrophysics Data System (ADS)

Yao, Yuangen; Ma, Chengzhang; Wang, Canjun; Yi, Ming; Gui, Rong

2018-02-01

We study the effects of multiplicative and additive cross-correlated sine-Wiener (CCSW) noises on the performance of sub-threshold periodic signal detection in the FitzHugh-Nagumo (FHN) neuron by calculating Fourier coefficients Q for measuring synchronization between sub-threshold input signal and the response of system. CCSW noises-induced transitions of electrical activity in the FHN neuron model can be observed. Moreover, the performance of sub-threshold periodic signal detection is achieved at moderate noise strength, cross-correlation time and cross-correlation strength of CCSW noises, which indicate the occurrence of CCSW noises-induced stochastic resonance. Furthermore, the performance of sub-threshold signal detection is strongly sensitive to cross-correlation time of CCSW noises. Therefore, the performance can be effectively controlled by regulating cross-correlation time of CCSW noises. These results provide a possible mechanism for amplifying or detecting the sub-threshold signal in the nervous system.

Evidence that the presence of psychosis in non-psychotic disorder is environment-dependent and mediated by severity of non-psychotic psychopathology.

PubMed

Guloksuz, S; van Nierop, M; Lieb, R; van Winkel, R; Wittchen, H-U; van Os, J

2015-08-01

Evidence suggests that in affective, non-psychotic disorders: (i) environmental exposures increase risk of subthreshold psychotic experiences (PEs) and strengthen connectivity between domains of affective and subthreshold psychotic psychopathology; and (ii) PEs are a marker of illness severity. In 3021 adolescents from the Early Developmental Stages of Psychopathology cohort, we tested whether the association between PEs and presence of DSM-IV mood disorder (MD)/obsessive-compulsive disorder (OCD) would be moderated by risk factors for psychosis (cannabis use, childhood trauma and urbanicity), using the interaction contrast ratio (ICR) method. Furthermore, we analysed whether the interaction between environment and PEs was mediated by non-psychotic psychopathology. The association between PEs and MD/OCD was moderated by urbanicity (ICR = 2.46, p = 0.005), cannabis use (ICR = 3.76, p = 0.010) and, suggestively, trauma (ICR = 1.91, p = 0.063). Exposure to more than one environmental risk factor increased the likelihood of co-expression of PEs in a dose-response fashion. Moderating effects of environmental exposures were largely mediated by the severity of general non-psychotic psychopathology (percentage explained 56-68%, all p < 0.001). Within individuals with MD/OCD, the association between PEs and help-seeking behaviour, as an index of severity, was moderated by trauma (ICR = 1.87, p = 0.009) and urbanicity (ICR = 1.48, p = 0.005), but not by cannabis use. In non-psychotic disorder, environmental factors increase the likelihood of psychosis admixture and help-seeking behaviour through an increase in general psychopathology. The findings are compatible with a relational model of psychopathology in which more severe clinical states are the result of environment-induced disturbances spreading through a psychopathology network.

Subthreshold attention-deficit/hyperactivity disorder is associated with functional impairments across domains: a comprehensive analysis in a large-scale community study.

PubMed

Hong, Soon-Beom; Dwyer, Dominic; Kim, Jae-Won; Park, Eun-Jin; Shin, Min-Sup; Kim, Boong-Nyun; Yoo, Hee-Jeong; Cho, In-Hee; Bhang, Soo-Young; Hong, Yun-Chul; Pantelis, Christos; Cho, Soo-Churl

2014-08-01

This study compared children who experience attention-deficit/hyperactivity disorder (ADHD) symptoms but do not meet criteria (i.e., subthreshold ADHD) with those with the full syndrome and healthy controls. Presence of ADHD symptoms was determined in a nationwide community sample of 921 children, aged 8-11 years. The main outcome measures comprised attentional symptoms, comorbidity profiles, academic performance, and neurocognitive ability (i.e., ADHD Rating Scale, Child Behavior Checklist, Learning Disability Evaluation Scale, and Stroop Color-Word Test, respectively). Subthreshold ADHD was equally prevalent in boys and girls, and more prevalent in low-income families. Throughout all the outcome measurements, subthreshold ADHD was both a significantly milder condition than full syndrome ADHD and a significantly more severe condition than non-ADHD status. The findings were consistent across the total as well as the subtest scores, and after correction for multiple comparisons (p < 0.0017). Children with subthreshold ADHD were found to experience significant symptoms and functional impairments. The results of this study support the clinical relevance of subthreshold ADHD in a childhood population. Subthreshold diagnostic criteria for ADHD may be more sensitive in detecting ADHD symptoms in girls than the full syndrome criteria, and subthreshold clinical, cognitive, and behavioral symptoms of ADHD may occur in a subset of children who are possibly more sensitive to their environment. Further consideration about the diagnostic threshold for ADHD may particularly benefit girls and children in low-income families.

Adolescent Subthreshold-Depression and Anxiety: Psychopathology, Functional Impairment and Increased Suicide Risk

ERIC Educational Resources Information Center

Balazs, Judit; Miklosi, Monika; Kereszteny, Agnes; Hoven, Christina W.; Carli, Vladimir; Wasserman, Camilla; Apter, Alan; Bobes, Julio; Brunner, Romuald; Cosman, Doina; Cotter, Padraig; Haring, Christian; Iosue, Miriam; Kaess, Michael; Kahn, Jean-Pierre; Keeley, Helen; Marusic, Dragan; Postuvan, Vita; Resch, Franz; Saiz, Pilar A.; Sisask, Merike; Snir, Avigal; Tubiana, Alexandra; Varnik, Airi; Sarchiapone, Marco; Wasserman, Danuta

2013-01-01

Background: Subthreshold-depression and anxiety have been associated with significant impairments in adults. This study investigates the characteristics of adolescent subthreshold-depression and anxiety with a focus on suicidality, using both categorical and dimensional diagnostic models. Methods: Data were drawn from the Saving and Empowering…

"Subthreshold" depression: is the distinction between depressive disorder not otherwise specified and adjustment disorder valid?

PubMed

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

2013-05-01

Patients with clinically significant symptoms of depression who do not meet the criteria for major depressive disorder or dysthymic disorder are considered to have subthreshold depression. According to DSM-IV, such patients should be diagnosed with depressive disorder not otherwise specified (NOS) if the development of the symptoms is not attributable to a stressful event or with adjustment disorder if the symptoms follow a stressor. Research on the treatment of subthreshold depression rarely addresses the distinction between depressive disorder NOS and adjustment disorder. In the present report from the Rhode Island Methods to Improve Diagnostic Assessment and Services (MIDAS) project, we examined the validity of this distinction. From December 1995 to June 2011, 3,400 psychiatric patients presenting to the Rhode Island Hospital outpatient practice were evaluated with semistructured diagnostic interviews for DSM-IV Axis I and Axis II disorders and measures of psychosocial morbidity. Slightly less than 10% (n = 300) of the 3,400 patients were diagnosed with depressive disorder NOS or adjustment disorder with depressed mood. The patients with depressive disorder NOS were significantly more often diagnosed with social phobia (P < .05) and a personality disorder (P < .01). The patients with depressive disorder NOS reported more anhedonia, increased appetite, increased sleep, and indecisiveness, whereas the patients with adjustment disorder reported more weight loss, reduced appetite, and insomnia. There was no significant difference between the groups in overall level of severity of depression or impaired functioning. The patients with depressive disorder NOS had a nonsignificantly elevated morbid risk of depression in their first-degree relatives. Clinically significant subthreshold depression was common in psychiatric outpatients, and the present results support the validity of distinguishing between depressive disorder NOS and adjustment disorder with depressed mood. Future studies of the treatment of subthreshold depression should account for this diagnostic distinction. © Copyright 2013 Physicians Postgraduate Press, Inc.

Threshold and subthreshold Generalized Anxiety Disorder (GAD) and suicide ideation.

PubMed

Gilmour, Heather

2016-11-16

Subthreshold Generalized Anxiety Disorder (GAD) has been reported to be at least as prevalent as threshold GAD and of comparable clinical significance. It is not clear if GAD is uniquely associated with the risk of suicide, or if psychiatric comorbidity drives the association. Data from the 2012 Canadian Community Health Survey-Mental Health were used to estimate the prevalence of threshold and subthreshold GAD in the household population aged 15 or older. As well, the relationship between GAD and suicide ideation was studied. Multivariate logistic regression was used in a sample of 24,785 people to identify significant associations, while adjusting for the confounding effects of sociodemographic factors and other mental disorders. In 2012, an estimated 722,000 Canadians aged 15 or older (2.6%) met the criteria for threshold GAD; an additional 2.3% (655,000) had subthreshold GAD. For people with threshold GAD, past 12-month suicide ideation was more prevalent among men than women (32.0% versus 21.2% respectively). In multivariate models that controlled sociodemographic factors, the odds of past 12-month suicide ideation among people with either past 12-month threshold or subthreshold GAD were significantly higher than the odds for those without GAD. When psychiatric comorbidity was also controlled, associations between threshold and subthreshold GAD and suicidal ideation were attenuated, but remained significant. Threshold and subthreshold GAD affect similar percentages of the Canadian household population. This study adds to the literature that has identified an independent association between threshold GAD and suicide ideation, and demonstrates that an association is also apparent for subthreshold GAD.

Psychophysiological response to virtual reality and subthreshold posttraumatic stress disorder symptoms in recently deployed military.

PubMed

Costanzo, Michelle E; Leaman, Suzanne; Jovanovic, Tanja; Norrholm, Seth D; Rizzo, Albert A; Taylor, Patricia; Roy, Michael J

2014-01-01

Subthreshold posttraumatic stress disorder (PTSD) has garnered recent attention because of the significant distress and functional impairment associated with the symptoms as well as the increased risk of progression to full PTSD. However, the clinical presentation of subthreshold PTSD can vary widely and therefore is not clearly defined, nor is there an evidence-based treatment approach. Thus, we aim to further the understanding of subthreshold PTSD symptoms by reporting the use of a virtual combat environment in eliciting distinctive psychophysiological responses associated with PTSD symptoms in a sample of subthreshold recently deployed US service members. Heart rate, skin conductance, electromyography (startle), respiratory rate, and blood pressure were monitored during three unique combat-related virtual reality scenarios as a novel procedure to assess subthreshold symptoms in a sample of 78 service members. The Clinician-Administered PTSD Scale was administered, and linear regression analyses were used to investigate the relationship between symptom clusters and physiological variables. Among the range of psychophysiological measures that were studied, regression analysis revealed heart rate as most strongly associated with Clinician-Administered PTSD Scale-based measures hyperarousal (R = 0.11, p = .035,) reexperiencing (R = 0.24, p = .001), and global PTSD symptoms (R = 0.17, p = .003). Our findings support the use of a virtual reality environment in eliciting physiological responses associated with subthreshold PTSD symptoms.

Panic disorder and subthreshold panic in the light of comorbidity: a follow-up study.

PubMed

Oral, Elif; Aydin, Nazan; Gulec, Mustafa; Oral, Meltem

2012-10-01

Especially in the presence of agoraphobia and comorbid conditions, panic disorder causes significant impairment in life quality. Although there are several studies about epidemiology and clinical features, subthreshold symptoms and courses of comorbidity have not been studied sufficiently in panic disorder. The current study assessed the courses of panic disorder and subthreshold panic symptoms in consideration of the major and subthreshold comorbid conditions. Patients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-diagnosed panic disorder were assessed using the panic disorder follow-up questionnaire, Panic and Agoraphobia Scale, Hamilton Depression Rating Scale, and State-Trait Anxiety Inventory. Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders was used to determine comorbidity, and all participants were received to 1-year follow-up. Comorbidity assessment showed that the threshold comorbidity decreased, while the subthreshold comorbidity increased at 1-year follow-up. Panic disorder symptom severity was decreased, but subthreshold panic symptoms continued to be present within the course of the illness. Presence of agoraphobia and duration of disease were significantly related with higher Panic and Agoraphobia Scale scores in the second assessment, and these relationships were independent from the treatment process. Even if the comorbidity and the severity of panic decrease with treatment, subthreshold panic and comorbid symptoms may still resist in panic disorder. Copyright © 2012 Elsevier Inc. All rights reserved.

Low-Voltage Organic Single-Crystal Field-Effect Transistor with Steep Subthreshold Slope.

PubMed

Yang, Fangxu; Sun, Lingjie; Han, Jiangli; Li, Baili; Yu, Xi; Zhang, Xiaotao; Ren, Xiaochen; Hu, Wenping

2018-03-06

Anodization is a promising technique to form high- k dielectrics for low-power organic field-effect transistor (OFET) applications. However, the surface quality of the dielectric, which is mainly inherited from the metal electrode, can be improved further than other fabrication techniques, such as sol-gel. In this study, we applied the template stripping method to fabricate a low-power single-crystalline OFET based on the anodized AlO x dielectric. We found that the template stripping method largely improves the surface roughness of the deposited Al and allows for the formation of a high-quality AlO x high- k dielectric by anodization. The ultraflat AlO x /SAM dielectric combined with a single-crystal 2,6-diphenylanthracene (DPA) semiconductor produced a nearly defect-free interface with a steep subthreshold swing (SS) of 66 mV/decade. The current device is a promising candidate for future ultralow-power applications. Other than metal deposition, template stripping could provide a general approach to improve thin-film quality for many other types of materials and processes.

Effect of the heterogeneous neuron and information transmission delay on stochastic resonance of neuronal networks

NASA Astrophysics Data System (ADS)

Wang, Qingyun; Zhang, Honghui; Chen, Guanrong

2012-12-01

We study the effect of heterogeneous neuron and information transmission delay on stochastic resonance of scale-free neuronal networks. For this purpose, we introduce the heterogeneity to the specified neuron with the highest degree. It is shown that in the absence of delay, an intermediate noise level can optimally assist spike firings of collective neurons so as to achieve stochastic resonance on scale-free neuronal networks for small and intermediate αh, which plays a heterogeneous role. Maxima of stochastic resonance measure are enhanced as αh increases, which implies that the heterogeneity can improve stochastic resonance. However, as αh is beyond a certain large value, no obvious stochastic resonance can be observed. If the information transmission delay is introduced to neuronal networks, stochastic resonance is dramatically affected. In particular, the tuned information transmission delay can induce multiple stochastic resonance, which can be manifested as well-expressed maximum in the measure for stochastic resonance, appearing every multiple of one half of the subthreshold stimulus period. Furthermore, we can observe that stochastic resonance at odd multiple of one half of the subthreshold stimulus period is subharmonic, as opposed to the case of even multiple of one half of the subthreshold stimulus period. More interestingly, multiple stochastic resonance can also be improved by the suitable heterogeneous neuron. Presented results can provide good insights into the understanding of the heterogeneous neuron and information transmission delay on realistic neuronal networks.

Patients with insomnia and subthreshold depression show marked worsening of insomnia after discontinuation of sleep promoting medication.

PubMed

Wichniak, Adam; Wierzbicka, Aleksandra; Jernajczyk, Wojciech

2011-08-15

To investigate whether the outcome of treatment with trazodone CR in primary insomnia differs between patients with and without subthreshold depression. 14 patients (9 females, mean age 57.3 ± 13.3) with primary insomnia and increased Beck Depression Inventory (BDI) scores (>10) and 15 sex- and age-matched patients with primary insomnia and low BDI scores (≤ 10) were treated with trazodone CR 25-150 mg/d for 3 months and followed for 1 month after discontinuation of the medication. The Athens Insomnia Scale (AIS), Sheehan Disability Scale (SDS), and Clinical Global Impression scale (CGI) were completed at baseline, after each month of treatment and after the first week of run-out phase. Additional assessment tools comprised sleep diaries, the Leeds Sleep Evaluation Questionnaire (LSEQ) and actigraphic recordings. Subjective sleep time increased by 61.5 ± 72.3 min in the group with low BDI and 60.0 ± 59.4 min in the group with increased BDI at the end of the treatment phase. The significant improvements were also observed in the AIS, CGI, LSEQ and SDS. During the run-out phase the improvement was sustained in patients with low BDI, while AIS scores, sleep latency and total sleep time deteriorated in patients with increased BDI. Patients with subthreshold depression, even if the depressive symptoms do not fulfill the time criteria for depressive episode, show marked worsening of insomnia after discontinuation of sleep promoting medication. Copyright © 2011 Elsevier Inc. All rights reserved.

The effect of subthreshold continuous electrical stimulation on the facial function of patients with Bell's palsy.

PubMed

Kim, Jin; Choi, Jae Young

2016-01-01

The drug regimen plus electrical stimulation was more effective in treating Bell's palsy than the conventional drug treatment alone. The effectiveness of such a sub-threshold, continuous, low frequency electrical stimulation suggests a new therapeutic approach to accelerate nerve regeneration and improve functional recovery after injury. The purpose of this study was to determine whether sub-threshold, continuous electrical stimulation at 20 Hz facilitates functional recovery of patients with Bell's palsy. The authors performed a prospective randomized study that included 60 patients with mild-to-moderate grade Bell's palsy (HB grade ≤4, SB grade ≥40), to evaluate the effect of developed electrical stimulation on the resolution of symptoms. Thirty patients were treated with prednisolone or/and acyclovir plus electrical stimulation within 7 days of the onset of symptoms. The other 30 patients were treated with only prednisolone or/and acyclovir as a control group. The overall rate of patient recovery among those treated with prednisolone or/and acyclovir plus electrical stimulation (96%) was significantly better (p < 0.05) than the rate among those treated with only prednisolone or/and acyclovir (88%).

Is the diagnostic threshold for bulimia nervosa clinically meaningful?

PubMed

Chapa, Danielle A N; Bohrer, Brittany K; Forbush, Kelsie T

2018-01-01

The DSM-5 differentiates full- and sub-threshold bulimia nervosa (BN) according to average weekly frequencies of binge eating and inappropriate compensatory behaviors. This study was the first to evaluate the modified frequency criterion for BN published in the DSM-5. The purpose of this study was to test whether community-recruited adults (N=125; 83.2% women) with current full-threshold (n=77) or sub-threshold BN (n=48) differed in comorbid psychopathology and eating disorder (ED) illness duration, symptom severity, and clinical impairment. Participants completed the Clinical Impairment Assessment and participated in semi-structured clinical interviews of ED- and non-ED psychopathology. Differences between the sub- and full-threshold BN groups were assessed using MANOVA and Chi-square analyses. ED illness duration, age-of-onset, body mass index (BMI), alcohol and drug misuse, and the presence of current and lifetime mood or anxiety disorders did not differ between participants with sub- and full-threshold BN. Participants with full-threshold BN had higher levels of clinical impairment and weight concern than those with sub-threshold BN. However, minimal clinically important difference analyses suggested that statistically significant differences between participants with sub- and full-threshold BN on clinical impairment and weight concern were not clinically significant. In conclusion, sub-threshold BN did not differ from full-threshold BN in clinically meaningful ways. Future studies are needed to identify an improved frequency criterion for BN that better distinguishes individuals in ways that will more validly inform prognosis and effective treatment planning for BN. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prevalence and correlates of obsessive-compulsive disorder and subthreshold obsessive-compulsive disorder among college students in Kerala, India

PubMed Central

Jaisoorya, T. S.; Janardhan Reddy, Y. C.; Nair, B. Sivasankaran; Rani, Anjana; Menon, Priya G.; Revamma, M.; Jeevan, C. R.; Radhakrishnan, K. S.; Jose, Vineetha; Thennarasu, K.

2017-01-01

Context: There are scarce data on the prevalence of adult obsessive-compulsive disorder (OCD) in India. Aims: The aim was to study the point prevalence of OCD and subthreshold OCD and its psychosocial correlates among college students in the district of Ernakulam, Kerala, India. Settings and Design: A cross-sectional survey of 5784 students of the age range of 18–25 years from 58 colleges was conducted. Materials and Methods: Students were self-administered the OCD subsection of the Clinical Interview Schedule-Revised, the Composite International Diagnostic Interview for obsessive-compulsive symptoms (OCSs), and other relevant instruments to identify OCD, subthreshold OCD, and related clinical measures. Statistical Analysis: The point prevalence of OCD and subthreshold OCD was determined. Categorical variables were compared using Chi-square/Fisher's exact tests as necessary. Differences between means were compared using the ANOVA. Results: The point prevalence of OCD was 3.3% (males = 3.5%; females = 3.2%). 8.5% students (males = 9.9%; females = 7.7%) fulfilled criteria of subthreshold OCD. Taboo thoughts (67.1%) and mental rituals (57.4%) were the most common symptoms in OCD subjects. Compared to those without obsessive-compulsive symptoms (OCSs), those with OCD and subthreshold OCD were more likely to have lifetime tobacco and alcohol use, psychological distress, suicidality, sexual abuse, and higher attention-deficit/hyperactivity disorder symptom scores. Subjects with subthreshold OCD were comparable to those with OCD except that OCD subjects had higher psychological distress scores and academic failures. Conclusions: OCD and subthreshold OCD are not uncommon in the community, both being associated with significant comorbidity. Hence, it is imperative that both are identified and treated in the community because of associated morbidity. PMID:28529361

How prevalent and morbid are subthreshold manifestations of major depression in adolescents? A literature review.

PubMed

Carrellas, Nicholas W; Biederman, Joseph; Uchida, Mai

2017-03-01

Major Depressive Disorder (MDD) among youth is a public health concern. Our aim was to examine the current body of knowledge to better characterize the prevalence and morbidity associated with subthreshold forms of MDD among youth. Given that MDD tends to develop gradually over time, we hypothesized a high prevalence and considerable impairment associated with youth suffering from depressive symptoms that fall short of full, syndromic status. A literature search was conducted using PubMed exclusively to identify studies assessing the prevalence and clinical characteristics of subthreshold MDD in adolescents. Six scientific papers that met our priori inclusion and exclusion criteria were identified. All papers sampled adolescents. The prevalence of subthreshold MDD ranged from 5% over the past year, to 29% over the two weeks prior to screening. These papers reported clinically significant morbidity associated with subthreshold MDD among adolescents, with evidence for elevated rates of psychiatric comorbidities, impaired functioning in social and familial domains, increased suicidality, and frequent mental health service utilization. Though we examined a sizeable and diverse sample, we only identified six cross-sectional informative studies for this review. Variability of subthreshold MDD and major outcome definitions across studies, likely limits the specificity of findings. Subthreshold MDD is prevalent among youth, and is associated with emotional and social impairments that reach the level of obtaining clinical care. These findings could lead to early intervention efforts aimed at mitigating the adverse outcomes associated with subthreshold MDD as well as the progression to full syndrome MDD. Our review documents that regardless of whether progression to full diagnostic status occurs, this condition is morbid. Copyright © 2016 Elsevier B.V. All rights reserved.

Efficacy and moderators of psychological interventions in treating subclinical symptoms of depression and preventing major depressive disorder onsets: protocol for an individual patient data meta-analysis of randomised controlled trials.

PubMed

Ebert, David D; Buntrock, Claudia; Reins, Jo Annika; Zimmermann, Johannes; Cuijpers, Pim

2018-03-16

The long-term effectiveness of psychological interventions for the treatment of subthreshold depression and the prevention of depression is unclear and effects vary among subgroups of patients, indicating that not all patients profit from such interventions. Randomised clinical trials are mostly underpowered to examine adequately subgroups and moderator effects. The aim of the present study is, therefore, to examine the short-term and long-term as well as moderator effects of psychological interventions compared with control groups in adults with subthreshold depression on depressive symptom severity, treatment response, remission, symptom deterioration, quality of life, anxiety and the prevention of major depressive disorder (MDD) onsets on individual patient level and study level using an individual patient data meta-analysis approach. Systematic searches in PubMed, PsycINFO, Embase and the Cochrane Central Register of Controlled Trials were conducted. We will use the following types of outcome criteria: (A) onset of major depression; (B) time to major depression onset; (C) observer-reported and self-reported depressive symptom severity; (D) response; (E) remission; (F) symptom deterioration; (G) quality of life, (H) anxiety; and (I) suicidal thoughts and behaviours. Multilevel models with participants nested within studies will be used. Missing data will be handled using a joint modelling approach to multiple imputation. A number of sensitivity analyses will be conducted in order test the robustness of our findings. The investigators of the primary trials have obtained ethical approval for the data used in the present study and for sharing the data, if this was necessary, according to local requirements and was not covered from the initial ethic assessment.This study will summarise the available evidence on the short-term and long-term effectiveness of preventive psychological interventions for the treatment of subthreshold depression and prevention of MDD onset. Identification of subgroups of patients in which those interventions are most effective will guide the development of evidence-based personalised interventions for patients with subthreshold depression. CRD42017058585. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Relative Contribution of Odour Intensity and Valence to Moral Decisions.

PubMed

Cecchetto, Cinzia; Rumiati, Raffaella Ida; Parma, Valentina

2017-01-01

Meta-analytic evidence showed that the chemical senses affect moral decisions. However, how odours impact on morality is currently unclear. Through a set of three studies, we assess whether and how odour intensity biases moral choices (Study 1a), its psychophysiological responses (Study 1b), as well as the behavioural and psychophysiological effects of odour valence on moral choices (Study 2). Study 1a suggests that the presence of an odour plays a role in shaping moral choice. Study 1b reveals that of two iso-pleasant versions of the same neutral odour, only the one presented sub-threshold (vs. supra-threshold) favours deontological moral choices, those based on the principle of not harming others even when such harm provides benefits. As expected, this odour intensity effect is tracked by skin conductance responses, whereas no difference in cardiac activity - proxy for the valence dimension - is revealed. Study 2 suggests that the same neutral odour presented sub-threshold increases deontological choices even when compared to iso-intense ambiguous odour, perceived as pleasant or unpleasant by half of the participants, respectively. Skin conductance responses, as expected, track odour pleasantness, but cardiac activity fails to do so. Results are discussed in the context of mechanisms alternative to disgust induction underlying moral choices.

Are there meaningful differences between major depressive disorder, dysthymic disorder, and their subthreshold variants?

PubMed

Moore, Michael T; Brown, Timothy A

2012-09-01

A number of researchers have proposed adding an increasing number of subthreshold variants of major depressive disorder (MDD) as new mood disorder. However, this research has suffered from a number of theoretical and methodological flaws that the current investigation has attempted to address. Individuals with MDD (n = 470) were compared with individuals with subthreshold MDD (n = 57). Individuals with MDD reported consistently more severe symptoms, albeit of small magnitude, as well as differences in comorbidity with only two disorders. Results also indicated that diagnosis did not significantly predict rate of symptom change when MDD was compared with its subthreshold variant. Taken together, the aforementioned evidence suggests that small differences exist between MDD and its subthreshold variant. In addition, the extent to which the latter serves as useful analogs for the former may depend upon the variables under study.

Psychotic experiences and incident suicidal ideation and behaviour: Disentangling the longitudinal associations from connected psychopathology.

PubMed

Honings, Steven; Drukker, Marjan; van Nierop, Martine; van Winkel, Ruud; Wittchen, Hans-Ulrich; Lieb, Roselind; Ten Have, Margreet; de Graaf, Ron; van Dorsselaer, Saskia; van Os, Jim

2016-11-30

This study examines the longitudinal associations between psychotic experiences (PE) and incident suicidal ideation and behaviour in the general population, and to what degree the association may be confounded by non-psychotic psychopathology. Data from three prospective, general population cohorts were combined into one dataset (n=15,837) and analysed using logistic regression, controlling for continuous measures of depression, anxiety and mania symptoms. Analyses were conducted in the entire sample, and in subsamples stratified by presence or absence of mental disorders. The presence of PE at baseline increased the risk of incident suicidal ideation and behaviour. However, adjustment for dimensional measures of psychopathology reduced effect sizes, although PE remained significantly associated with suicide attempts. Further examination of the associations revealed that PE were only associated with suicide attempts in individuals with at least one mental disorder. Similarly, in individuals without mental disorders, the risk of suicidal ideation increased as PE co-occurred with more symptom domains. The results of this study confirm that individuals with PE are at increased risk of suicidal ideation and behaviour. However, these associations are not specific, but reflect the increased risk of suicidal ideation in individuals with subthreshold multidimensional psychopathology and suicide attempts in individuals with co-occurring mental disorders. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Subthreshold Diode Micropulse Laser Photocoagulation (SDM) as Invisible Retinal Phototherapy for Diabetic Macular Edema: A Review

PubMed Central

Luttrull, Jeffrey K; Dorin, Giorgio

2012-01-01

Purpose: To present the state-of-the-art of subthreshold diode laser micropulse photocoagulation (SDM) as invisible retinal phototherapy for diabetic macular edema (DME). Method: To review the role and evolution of retinal laser treatment for DME. Results: Thermal laser retinal photocoagulation has been the cornerstone of treatment for diabetic macular edema for over four decades. Throughout, laser induced retinal damage produced by conventional photocoagulation has been universally accepted as necessary to produce a therapeutic benefit, despite the inherent risks, adverse effects and limitations of thermally destructive treatment. Recently, SDM, performed as invisible retinal phototherapy for DME, has been found to be effective in the absence of any retinal damage or adverse effect, fundamentally altering our understanding of laser treatment for retinal disease. Summary: The discovery of clinically effective and harmless SDM treatment for DME offers exciting new information that will improve our understanding of laser treatment for retinal disease, expand treatment indications, and improve patient outcomes. PMID:22587512

High performance MoS2 TFT using graphene contact first process

NASA Astrophysics Data System (ADS)

Chang Chien, Chih-Shiang; Chang, Hsun-Ming; Lee, Wei-Ta; Tang, Ming-Ru; Wu, Chao-Hsin; Lee, Si-Chen

2017-08-01

An ohmic contact of graphene/MoS2 heterostructure is determined by using ultraviolet photoelectron spectroscopy (UPS). Since graphene shows a great potential to replace metal contact, a direct comparison of Cr/Au contact and graphene contact on the MoS2 thin film transistor (TFT) is made. Different from metal contacts, the work function of graphene can be modulated. As a result, the subthreshold swing can be improved. And when Vg

Subthreshold diode micropulse laser photocoagulation (SDM) as invisible retinal phototherapy for diabetic macular edema: a review.

PubMed

Luttrull, Jeffrey K; Dorin, Giorgio

2012-07-01

To present the state-of-the-art of subthreshold diode laser micropulse photocoagulation (SDM) as invisible retinal phototherapy for diabetic macular edema (DME). To review the role and evolution of retinal laser treatment for DME. Thermal laser retinal photocoagulation has been the cornerstone of treatment for diabetic macular edema for over four decades. Throughout, laser induced retinal damage produced by conventional photocoagulation has been universally accepted as necessary to produce a therapeutic benefit, despite the inherent risks, adverse effects and limitations of thermally destructive treatment. Recently, SDM, performed as invisible retinal phototherapy for DME, has been found to be effective in the absence of any retinal damage or adverse effect, fundamentally altering our understanding of laser treatment for retinal disease. The discovery of clinically effective and harmless SDM treatment for DME offers exciting new information that will improve our understanding of laser treatment for retinal disease, expand treatment indications, and improve patient outcomes.

Effect of Al doping on performance of ZnO thin film transistors

NASA Astrophysics Data System (ADS)

Dong, Junchen; Han, Dedong; Li, Huijin; Yu, Wen; Zhang, Shendong; Zhang, Xing; Wang, Yi

2018-03-01

In this work, we investigate the Aluminum-doped Zinc Oxide (AZO) thin films and their feasibility as the active layer for thin film transistors (TFTs). A comparison on performance is made between the AZO TFTs and ZnO TFTs. The electrical properties such as saturation mobility, subthreshold swing, and on-to-off current ratio are improved when AZO is utilized as the active layer. Oxygen component of the thin film materials indicates that Al is the suppressor for oxygen defect in active layer, which improves the subthreshold swing. Moreover, based on band structure analyzation, we observe that the carrier concentration of AZO is higher than ZnO, leading to the enhancement of saturation mobility. The microstructure of the thin films convey that the AZO films exhibit much smaller grain boundaries than ZnO films, which results in the lower off-state current and higher on-to-off current ratio of AZO TFTs. The AZO thin films show huge potential to be the active layer of TFTs.

Examining various subthreshold definitions of PTSD using the Clinician Administered PTSD Scale for DSM-5.

PubMed

Franklin, C Laurel; Raines, Amanda M; Chambliss, Jessica L; Walton, Jessica L; Maieritsch, Kelly P

2018-07-01

The Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5; American Psychiatric Association [APA], 2013) includes Other- and Unspecified- Trauma and Stressor-Related Disorders to capture subthreshold Posttraumatic Stress Disorder (PTSD) symptoms. However, the DSM-5 does not specify the number or type of symptoms needed to assign them. The purpose of the current study was to extend our understanding of subthreshold PTSD by comparing four commonly used definitions adapted to the DSM-5 PTSD criteria in an outpatient treatment-seeking sample. Veterans (N = 193) presenting to PTSD clinics were assessed using the Clinician Administered PTSD Scale for DSM-5 (CAPS-5). Participants reported a criterion A traumatic event, but did not meet criteria for threshold-PTSD. We hypothesized that the number of veterans captured would be highest when fewer specific criterion sets were required by the subthreshold definition. Our hypothesis was upheld in that the more criteria required by the subthreshold PTSD definition, the lower the number of veterans counted within the group. The study consisted primarily of trauma treatment-seeking male veterans, with chronic PTSD symptoms. In addition, the sample size was small and was collected as part of routine clinical care. These results support previous contentions around careful decision making when defining what constitutes subthreshold PTSD in research and clinical work. It also points to the need for continued research to better understand the diagnostic and treatment implications of subthreshold PTSD. Published by Elsevier B.V.

Physics of Gate Modulated Resonant Tunneling (RT)-FETs: Multi-barrier MOSFET for steep slope and high on-current

NASA Astrophysics Data System (ADS)

Afzalian, Aryan; Colinge, Jean-Pierre; Flandre, Denis

2011-05-01

A new concept of nanoscale MOSFET, the Gate Modulated Resonant Tunneling Transistor (RT-FET), is presented and modeled using 3D Non-Equilibrium Green's Function simulations enlightening the main physical mechanisms. Owing to the additional tunnel barriers and the related longitudinal confinement present in the device, the density of state is reduced in its off-state, while remaining comparable in its on-state, to that of a MOS transistor without barriers. The RT-FET thus features both a lower RT-limited off-current and a faster increase of the current with V G, i.e. an improved slope characteristic, and hence an improved Ion/ Ioff ratio. Such improvement of the slope can happen in subthreshold regime, and therefore lead to subthreshold slope below the kT/q limit. In addition, faster increase of current and improved slope occur above threshold and lead to high thermionic on-current and significant Ion/ Ioff ratio improvement, even with threshold voltage below 0.2 V and supply voltage V dd of a few hundreds of mV as critically needed for future technology nodes. Finally RT-FETs are intrinsically immune to source-drain tunneling and are therefore promising candidate for extending the roadmap below 10 nm.

The Subthreshold Autism Trait Questionnaire (SATQ): Development of a Brief Self-Report Measure of Subthreshold Autism Traits

ERIC Educational Resources Information Center

Kanne, Stephen M.; Wang, Jennifer; Christ, Shawn E.

2012-01-01

The current study was motivated by a need for a self-report questionnaire that assesses a broad range of subthreshold autism traits, is brief and easily administered, and is relevant to the general population. An initial item pool was administered to 1,709 students. Structural validity analysis resulted in a 24-item questionnaire termed the…

Remote vibrotactile noise improves light touch sensation in stroke survivors’ fingertips via stochastic resonance

PubMed Central

2013-01-01

Background and purpose Stroke rehabilitation does not often integrate both sensory and motor recovery. While subthreshold noise was shown to enhance sensory signal detection at the site of noise application, having a noise-generating device at the fingertip to enhance fingertip sensation and potentially enhance dexterity for stroke survivors is impractical, since the device would interfere with object manipulation. This study determined if remote application of subthreshold vibrotactile noise (away from the fingertips) improves fingertip tactile sensation with potential to enhance dexterity for stroke survivors. Methods Index finger and thumb pad sensation was measured for ten stroke survivors with fingertip sensory deficit using the Semmes-Weinstein Monofilament and Two-Point Discrimination Tests. Sensation scores were measured with noise applied at one of three intensities (40%, 60%, 80% of the sensory threshold) to one of four locations of the paretic upper extremity (dorsal hand proximal to the index finger knuckle, dorsal hand proximal to the thumb knuckle, dorsal wrist, volar wrist) in a random order, as well as without noise at beginning (Pre) and end (Post) of the testing session. Results Vibrotactile noise of all intensities and locations instantaneously and significantly improved Monofilament scores of the index fingertip and thumb tip (p < .01). No significant effect of the noise was seen for the Two-Point Discrimination Test scores. Conclusions Remote application of subthreshold (imperceptible) vibrotactile noise at the wrist and dorsal hand instantaneously improved stroke survivors’ light touch sensation, independent of noise location and intensity. Vibrotactile noise at the wrist and dorsal hand may have enhanced the fingertips’ light touch sensation via stochastic resonance and interneuronal connections. While long-term benefits of noise in stroke patients warrants further investigation, this result demonstrates potential that a wearable device applying vibrotactile noise at the wrist could enhance sensation and grip ability without interfering with object manipulation in everyday tasks. PMID:24112371

Stochastic multiresonance in coupled excitable FHN neurons

NASA Astrophysics Data System (ADS)

Li, Huiyan; Sun, Xiaojuan; Xiao, Jinghua

2018-04-01

In this paper, effects of noise on Watts-Strogatz small-world neuronal networks, which are stimulated by a subthreshold signal, have been investigated. With the numerical simulations, it is surprisingly found that there exist several optimal noise intensities at which the subthreshold signal can be detected efficiently. This indicates the occurrence of stochastic multiresonance in the studied neuronal networks. Moreover, it is revealed that the occurrence of stochastic multiresonance has close relationship with the period of subthreshold signal Te and the noise-induced mean period of the neuronal networks T0. In detail, we find that noise could induce the neuronal networks to generate stochastic resonance for M times if Te is not very large and falls into the interval ( M × T 0 , ( M + 1 ) × T 0 ) with M being a positive integer. In real neuronal system, subthreshold signal detection is very meaningful. Thus, the obtained results in this paper could give some important implications on detecting subthreshold signal and propagating neuronal information in neuronal systems.

2D modeling based comprehensive analysis of short channel effects in DMG strained VSTB FET

NASA Astrophysics Data System (ADS)

Saha, Priyanka; Banerjee, Pritha; Sarkar, Subir Kumar

2018-06-01

The paper aims to develop two dimensional analytical model of the proposed dual material (DM) Vertical Super Thin Body (VSTB) strained Field Effect Transistor (FET) with focus on its short channel behaviour in nanometer regime. Electrostatic potential across gate/channel and dielectric wall/channel interface is derived by solving 2D Poisson's equation with parabolic approximation method by applying appropriate boundary conditions. Threshold voltage is then calculated by using the criteria of minimum surface potential considering both gate and dielectric wall side potential. Performance analysis of the present structure is demonstrated in terms of potential, electric field, threshold voltage characteristics and subthreshold behaviour by varying various device parameters and applied biases. Effect of application of strain in channel is further explored to establish the superiority of the proposed device in comparison to conventional VSTB FET counterpart. All analytical results are compared with Silvaco ATLAS device simulated data to substantiate the accuracy of our derived model.

Subthreshold depressive disorder in adolescents: predictors of escalation to full-syndrome depressive disorders.

PubMed

Klein, Daniel N; Shankman, Stewart A; Lewinsohn, Peter M; Seeley, John R

2009-07-01

Subthreshold depressive disorder is one of the best established risk factors for the onset of full-syndrome depressive disorders. However, many youths with subthreshold depressive disorder do not develop full-syndrome depression. We examined predictors of escalation to full-syndrome depressive disorders in a community sample of 225 adolescents with subthreshold depressive disorder. Criteria for subthreshold depressive disorder were an episode of depressed mood or loss of interest or pleasure lasting at least 1 week and at least two of the seven other DSM-IV-associated symptoms for major depression. Participants were assessed four times from mid-adolescence to age 30 years using semistructured diagnostic interviews. The estimated risk for escalation to full-syndrome depressive disorders was 67%. Five variables accounted for unique variance in predicting escalation: severity of depressive symptoms, medical conditions/symptoms, history of suicidal ideation, history of anxiety disorder, and familial loading for depression. Adolescents with three or more risk factors had an estimated 90% chance of escalating to full-syndrome depressive disorder, compared with 47% of adolescents with fewer than three risk factors. These data may be useful in identifying a subgroup of youths with subthreshold depressive disorder who are at especially high risk for escalating to full-syndrome depressive disorders.

Subthreshold Depressive Disorder in Adolescents: Predictors of Escalation to Full-Syndrome Depressive Disorders

PubMed Central

KLEIN, DANIEL N.; SHANKMAN, STEWART A.; LEWINSOHN, PETER M.; SEELEY, JOHN R.

2010-01-01

Objectives Subthreshold depressive disorder is one of the best established risk factors for the onset of full-syndrome depressive disorders. However, many youths with subthreshold depressive disorder do not develop full-syndrome depression. We examined predictors of escalation to full-syndrome depressive disorders in a community sample of 225 adolescents with subthreshold depressive disorder. Method Criteria for subthreshold depressive disorder were an episode of depressed mood or loss of interest or pleasure lasting at least 1 week and at least two of the seven other DSM-IV-associated symptoms for major depression. Participants were assessed four times from mid-adolescence to age 30 years using semistructured diagnostic interviews. Results The estimated risk for escalation to full-syndrome depressive disorders was 67%. Five variables accounted for unique variance in predicting escalation: severity of depressive symptoms, medical conditions/symptoms, history of suicidal ideation, history of anxiety disorder, and familial loading for depression. Adolescents with three or more risk factors had an estimated 90% chance of escalating to full-syndrome depressive disorder, compared with 47% of adolescents with fewer than three risk factors. Conclusions These data may be useful in identifying a subgroup of youths with subthreshold depressive disorder who are at especially high risk for escalating to full-syndrome depressive disorders. PMID:19465876

Does comorbid subthreshold anxiety affect clinical presentation and treatment response in depression? A preliminary 12-month naturalistic study.

PubMed

Altamura, A Carlo; Montresor, Claudio; Salvadori, Daniele; Mundo, Emanuela

2004-12-01

The aim of this study was to evaluate the effects of comorbid subthreshold anxiety on the course and the treatment of Depressive Disorders. The sample studied comprised four groups defined by the DSM-IV Axis I diagnosis: (1) Patients with a Major Depressive Disorder (MDD) and an Anxiety Disorder (DA); (2) patients with MDD and a subthreshold Anxiety Disorder (Da); (3) patients with subthreshold depression and an Anxiety Disorder (dA); (4) patients with subthreshold depression and subthreshold anxiety (da). HAMD, HAMA and CGI rating scales were administered monthly for 12 months while patients were treated with different antidepressants. Significant differences were found among the four groups with respect to the baseline depressive symptoms: Da presented more frequently suicidal ideation (chi2=9.568, d.f.=3, p=0.023), psychomotor retardation (chi2=12.568, d.f.=3, p=0.006), sexual dysfunctions (chi2=7.761, d.f.=3, p=0.05), hypochondriacal ideation (chi2=13.633, d.f.=3, p=0.003), weight loss (chi2=9.520, d.f.=3, p=0.023), and diurnal variation of symptoms (chi2=13.258, d.f.=3, p=0.004). With respect to the treatment response Da patients showed an overall worse response to antidepressants, having a longer latency and a lower reduction of symptoms. These results suggest that patients with Major Depression and subthreshold anxiety present with a more severe baseline clinical picture and seem to have a less efficient response to antidepressants.

Improved retinal and visual function following panmacular subthreshold diode micropulse laser for retinitis pigmentosa.

PubMed

Luttrull, Jeffrey K

2018-06-01

To examine the effect of subthreshold diode micropulse laser (SDM) on pattern electroretinography (PERG) and visual function in retinitis pigmentosa (RP). The records of all patients (pts) undergoing SDM in a vitreoretinal subspecialty practice were reviewed. Inclusion criteria included the presence of RP evaluated before and after SDM by PERG. As a secondary outcome measure, the results of automated omnifield resolution perimetry (ORP) were also reviewed. All eyes undergoing SDM for RP were eligible study, including 26 eyes of 15 pts; seven male and eight female, aged 16-69 (avg. 47) years. Retinal function by PERG improved by all indices, with significant improvements in the 24° field signal latency measures; the MagD(µV)/ Mag(µV) ratio (P < 0.0001) and the MagD(µV) amplitude (P = 0.0003). ORP significantly improved by all indices (p = 0.02-0.002). Average best-corrected chart visual acuities improved from 0.6 to 0.4 logMAR units (p = 0.02). There were no adverse treatment effects. SDM significantly improved chart visual acuity, mesopic logMAR visual acuity perimetry, and retinal function by PERG in RP without adverse treatment effects. Treatment responses indicate a significant capacity for rescue of dysfunctional retina. These results suggest that early and periodic treatment with SDM might slow disease progression and reduce long-term vision loss.

Transition to subthreshold activity with the use of phase shifting in a model thalamic network

NASA Astrophysics Data System (ADS)

Thomas, Elizabeth; Grisar, Thierry

1997-05-01

Absence epilepsy involves a state of low frequency synchronous oscillations by the involved neuronal networks. These oscillations may be either above or subthreshold. In this investigation, we studied the methods which could be utilized to transform the threshold activity of neurons in the network to a subthreshold state. A model thalamic network was constructed using the Hodgkin Huxley framework. Subthreshold activity was achieved by the application of stimuli to the network which caused phase shifts in the oscillatory activity of selected neurons in the network. In some instances the stimulus was a periodic pulse train of low frequency to the reticular thalamic neurons of the network while in others, it was a constant hyperpolarizing current applied to the thalamocortical neurons.

Dual-Gate p-GaN Gate High Electron Mobility Transistors for Steep Subthreshold Slope.

PubMed

Bae, Jong-Ho; Lee, Jong-Ho

2016-05-01

A steep subthreshold slope characteristic is achieved through p-GaN gate HEMT with dual-gate structure. Obtained subthreshold slope is less than 120 μV/dec. Based on the measured and simulated data obtained from single-gate device, breakdown of parasitic floating-base bipolar transistor and floating gate charged with holes are responsible to increase abruptly in drain current. In the dual-gate device, on-current degrades with high temperature but subthreshold slope is not changed. To observe the switching speed of dual-gate device and transient response of drain current are measured. According to the transient responses of drain current, switching speed of the dual-gate device is about 10(-5) sec.

Olfactory-visual integration facilitates perception of subthreshold negative emotion.

PubMed

Novak, Lucas R; Gitelman, Darren R; Schuyler, Brianna; Li, Wen

2015-10-01

A fast growing literature of multisensory emotion integration notwithstanding, the chemical senses, intimately associated with emotion, have been largely overlooked. Moreover, an ecologically highly relevant principle of "inverse effectiveness", rendering maximal integration efficacy with impoverished sensory input, remains to be assessed in emotion integration. Presenting minute, subthreshold negative (vs. neutral) cues in faces and odors, we demonstrated olfactory-visual emotion integration in improved emotion detection (especially among individuals with weaker perception of unimodal negative cues) and response enhancement in the amygdala. Moreover, while perceptual gain for visual negative emotion involved the posterior superior temporal sulcus/pSTS, perceptual gain for olfactory negative emotion engaged both the associative olfactory (orbitofrontal) cortex and amygdala. Dynamic causal modeling (DCM) analysis of fMRI timeseries further revealed connectivity strengthening among these areas during crossmodal emotion integration. That multisensory (but not low-level unisensory) areas exhibited both enhanced response and region-to-region coupling favors a top-down (vs. bottom-up) account for olfactory-visual emotion integration. Current findings thus confirm the involvement of multisensory convergence areas, while highlighting unique characteristics of olfaction-related integration. Furthermore, successful crossmodal binding of subthreshold aversive cues not only supports the principle of "inverse effectiveness" in emotion integration but also accentuates the automatic, unconscious quality of crossmodal emotion synthesis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Black Phosphorus Based Field Effect Transistors with Simultaneously Achieved Near Ideal Subthreshold Swing and High Hole Mobility at Room Temperature.

PubMed

Liu, Xinke; Ang, Kah-Wee; Yu, Wenjie; He, Jiazhu; Feng, Xuewei; Liu, Qiang; Jiang, He; Dan Tang; Wen, Jiao; Lu, Youming; Liu, Wenjun; Cao, Peijiang; Han, Shun; Wu, Jing; Liu, Wenjun; Wang, Xi; Zhu, Deliang; He, Zhubing

2016-04-22

Black phosphorus (BP) has emerged as a promising two-dimensional (2D) material for next generation transistor applications due to its superior carrier transport properties. Among other issues, achieving reduced subthreshold swing and enhanced hole mobility simultaneously remains a challenge which requires careful optimization of the BP/gate oxide interface. Here, we report the realization of high performance BP transistors integrated with HfO2 high-k gate dielectric using a low temperature CMOS process. The fabricated devices were shown to demonstrate a near ideal subthreshold swing (SS) of ~69 mV/dec and a room temperature hole mobility of exceeding >400 cm(2)/Vs. These figure-of-merits are benchmarked to be the best-of-its-kind, which outperform previously reported BP transistors realized on traditional SiO2 gate dielectric. X-ray photoelectron spectroscopy (XPS) analysis further reveals the evidence of a more chemically stable BP when formed on HfO2 high-k as opposed to SiO2, which gives rise to a better interface quality that accounts for the SS and hole mobility improvement. These results unveil the potential of black phosphorus as an emerging channel material for future nanoelectronic device applications.

Post-traumatic stress disorder dimensions and asthma morbidity in World Trade Center rescue and recovery workers.

PubMed

Mindlis, I; Morales-Raveendran, E; Goodman, E; Xu, K; Vila-Castelar, C; Keller, K; Crawford, G; James, S; Katz, C L; Crowley, L E; de la Hoz, R E; Markowitz, S; Wisnivesky, J P

2017-09-01

Using data from a cohort of World Trade Center (WTC) rescue and recovery workers with asthma, we assessed whether meeting criteria for post-traumatic stress disorder (PTSD), sub-threshold PTSD, and for specific PTSD symptom dimensions are associated with increased asthma morbidity. Participants underwent a Structured Clinical Interview for Diagnostic and Statistical Manual to assess the presence of PTSD following DSM-IV criteria during in-person interviews between December 2013 and April 2015. We defined sub-threshold PTSD as meeting criteria for two of three symptom dimensions: re-experiencing, avoidance, or hyper-arousal. Asthma control, acute asthma-related healthcare utilization, and asthma-related quality of life data were collected using validated scales. Unadjusted and multiple regression analyses were performed to assess the relationship between sub-threshold PTSD and PTSD symptom domains with asthma morbidity measures. Of the 181 WTC workers with asthma recruited into the study, 28% had PTSD and 25% had sub-threshold PTSD. Patients with PTSD showed worse asthma control, higher rates of inpatient healthcare utilization, and poorer asthma quality of life than those with sub-threshold or no PTSD. After adjusting for potential confounders, among patients not meeting the criteria for full PTSD, those presenting symptoms of re-experiencing exhibited poorer quality of life (p = 0.003). Avoidance was associated with increased acute healthcare use (p = 0.05). Sub-threshold PTSD was not associated with asthma morbidity (p > 0.05 for all comparisons). There may be benefit in assessing asthma control in patients with sub-threshold PTSD symptoms as well as those with full PTSD to more effectively identify ongoing asthma symptoms and target management strategies.

Sympathetic Release of Splenic Monocytes Promotes Recurring Anxiety Following Repeated Social Defeat.

PubMed

McKim, Daniel B; Patterson, Jenna M; Wohleb, Eric S; Jarrett, Brant L; Reader, Brenda F; Godbout, Jonathan P; Sheridan, John F

2016-05-15

Neuroinflammatory signaling may contribute to the pathophysiology of chronic anxiety disorders. Previous work showed that repeated social defeat (RSD) in mice promoted stress-sensitization that was characterized by the recurrence of anxiety following subthreshold stress 24 days after RSD. Furthermore, splenectomy following RSD prevented the recurrence of anxiety in stress-sensitized mice. We hypothesize that the spleen of RSD-exposed mice became a reservoir of primed monocytes that were released following neuroendocrine activation by subthreshold stress. Mice were subjected to subthreshold stress (i.e., single cycle of social defeat) 24 days after RSD, and immune and behavioral measures were taken. Subthreshold stress 24 days after RSD re-established anxiety-like behavior that was associated with egress of Ly6C(hi) monocytes from the spleen. Moreover, splenectomy before RSD blocked monocyte trafficking to the brain and prevented anxiety-like behavior following subthreshold stress. Splenectomy, however, had no effect on monocyte accumulation or anxiety when determined 14 hours after RSD. In addition, splenocytes cultured 24 days after RSD exhibited a primed inflammatory phenotype. Peripheral sympathetic inhibition before subthreshold stress blocked monocyte trafficking from the spleen to the brain and prevented the re-establishment of anxiety in RSD-sensitized mice. Last, β-adrenergic antagonism also prevented splenic monocyte egress after acute stress. The spleen served as a unique reservoir of primed monocytes that were readily released following sympathetic activation by subthreshold stress that promoted the re-establishment of anxiety. Collectively, the long-term storage of primed monocytes in the spleen may have a profound influence on recurring anxiety disorders. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Sub-threshold Post Traumatic Stress Disorder in the WHO World Mental Health Surveys

PubMed Central

McLaughlin, Katie A.; Koenen, Karestan C.; Friedman, Matthew J.; Ruscio, Ayelet Meron; Karam, Elie G.; Shahly, Victoria; Stein, Dan J.; Hill, Eric D.; Petukhova, Maria; Alonso, Jordi; Andrade, Laura Helena; Angermeyer, Matthias C.; Borges, Guilherme; de Girolamo, Giovanni; de Graaf, Ron; Demyttenaere, Koen; Florescu, Silvia E.; Mladenova, Maya; Posada-Villa, Jose; Scott, Kate M.; Takeshima, Tadashi; Kessler, Ronald C.

2014-01-01

Background Although only a minority of people exposed to a traumatic event (TE) develops PTSD, symptoms not meeting full PTSD criteria are common and often clinically significant. Individuals with these symptoms have sometimes been characterized as having sub-threshold PTSD, but no consensus exists on the optimal definition of this term. Data from a large cross-national epidemiological survey are used to provide a principled basis for such a definition. Methods The WHO World Mental Health (WMH) Surveys administered fully-structured psychiatric diagnostic interviews to community samples in 13 countries containing assessments of PTSD associated with randomly selected TEs. Focusing on the 23,936 respondents reporting lifetime TE exposure, associations of approximated DSM-5 PTSD symptom profiles with six outcomes (distress-impairment, suicidality, comorbid fear-distress disorders, PTSD symptom duration) were examined to investigate implications of different sub-threshold definitions. Results Although consistently highest distress-impairment, suicidality, comorbidity, and symptom duration were observed among the 3.0% of respondents with DSM-5 PTSD than other symptom profiles, the additional 3.6% of respondents meeting two or three of DSM-5 Criteria BE also had significantly elevated scores for most outcomes. The proportion of cases with threshold versus sub-threshold PTSD varied depending on TE type, with threshold PTSD more common following interpersonal violence and sub-threshold PTSD more common following events happening to loved ones. Conclusions Sub-threshold DSM-5 PTSD is most usefully defined as meeting two or three of the DSM-5 Criteria B-E. Use of a consistent definition is critical to advance understanding of the prevalence, predictors, and clinical significance of sub-threshold PTSD. PMID:24842116

Sympathetic Release of Splenic Monocytes Promotes Recurring Anxiety Following Repeated Social Defeat

PubMed Central

McKim, Daniel B.; Patterson, Jenna M.; Wohleb, Eric S.; Jarrett, Brant; Reader, Brenda; Godbout, Jonathan P.; Sheridan, John F.

2015-01-01

Background Neuroinflammatory signaling may contribute to the pathophysiology of chronic anxiety disorders. Previous work showed that repeated social defeat (RSD) in mice promoted stress-sensitization that was characterized by the recurrence of anxiety following sub-threshold stress 24 days after RSD. Furthermore, splenectomy following RSD prevented the recurrence of anxiety in stress-sensitized (SS) mice. We hypothesize that the spleen of RSD-exposed mice became a reservoir of primed monocytes that were released following neuroendocrine activation by sub-threshold stress. Methods Mice were subjected to sub-threshold stress (i.e., single cycle of social defeat) 24 days after RSD, and immune and behavioral measures were taken. Results Sub-threshold stress 24 days after RSD re-established anxiety-like behavior that was associated with egress of Ly6Chi monocytes from the spleen. Moreover, splenectomy prior to RSD blocked monocyte trafficking to the brain and prevented anxiety-like behavior following sub-threshold stress. Splenectomy, however, had no effect on monocyte accumulation or anxiety when determined 14 hours after RSD. In addition, splenocytes cultured 24 days after RSD exhibited a primed inflammatory phenotype. Peripheral sympathetic inhibition prior to sub-threshold stress blocked monocyte trafficking from the spleen to the brain and prevented the re-establishment of anxiety in RSD-sensitized mice. Last, β-adrenergic antagonism also prevented splenic monocyte egress after acute stress. Conclusion The spleen served as a unique reservoir of primed monocytes that were readily released following sympathetic activation by sub-threshold stress that promoted the re-establishment of anxiety. Collectively, the long-term storage of primed monocytes in the spleen may have a profound influence on recurring anxiety disorders. PMID:26281717

Predicting the onset of major depressive disorder and dysthymia in older adults with subthreshold depression: a community based study.

PubMed

Cuijpers, Pim; Beekman, Aartjan; Smit, Filip; Deeg, Dorly

2006-09-01

It is well-established that the incidence of major depressive disorder is increased in subjects with subthreshold depression. A new research area focuses on the possibilities of preventing the onset of major depressive disorders in subjects with subthreshold depression. An important research question for this research area is which subjects with subthreshold depression will develop a full-blown depressive disorder and which will not. We selected 154 older subjects with subthreshold depression (CES-D>16) but no DSM mood disorder from a longitudinal study among a large population based cohort aged between 55 and 85 years in The Netherlands. Of these subjects, 31 (20.1%) developed a mood disorder (major depression and/or dysthymia) at three-year or six-year follow-up. We examined risk factors and individual symptoms of mood disorder as predictors of onset of mood disorder. Two variables were found to be significant predictors in both bivariate and multivariate analyses: eating problems and sleep problems. The incidence of mood disorders differed strongly for different subpopulations, varying from 9% (for those not having any of the two risk factors) to 57% (for those having both risk factors). It appears to be possible to predict to a certain degree whether a subject with subthreshold depression will develop a mood disorder during the following years. Copyright (c) 2006 John Wiley & Sons, Ltd.

Definitions and factors associated with subthreshold depressive conditions: a systematic review

PubMed Central

2012-01-01

Background Subthreshold depressive disorders (minor and subthrehold depression) have been defined in a wide range of forms, varying on the number of symptoms and duration required. Disability associated with these conditions has also been reported. Our aim was to review the different definitions and to determine factors associated with these conditions in order to clarify the nosological implications of these disorders. Methods A Medline search was conducted of the published literature between January 2001 and September 2011. Bibliographies of the retrieved papers were also analysed. Results There is a wide heterogeneity in the definition and diagnostic criteria of minor and subthreshold depression. Minor depression was defined according to DSM-IV criteria. Regarding subthreshold depression, also called subclinical depression or subsyndromal symptomatic depression, between 2 and 5 depressive symptoms were required for the diagnosis, and a minimum duration of 2 weeks. Significant impairment associated with subthreshold depressive conditions, as well as comorbidity with other mental disorders, has been described. Conclusions Depression as a disorder is better explained as a spectrum rather than as a collection of discrete categories. Minor and subthreshold depression are common conditions and patients falling below the diagnostic threshold experience significant difficulties in functioning and a negative impact on their quality of life. Current diagnostic systems need to reexamine the thresholds for depressive disorders and distinguish them from ordinary feelings of sadness. PMID:23110575

A novel pattern of longitudinal muscle contraction with subthreshold pharyngeal stimulus: a possible mechanism of lower esophageal sphincter relaxation.

PubMed

Leslie, Eric; Bhargava, Valmik; Mittal, Ravinder K

2012-03-01

A subthreshold pharyngeal stimulus induces lower esophageal sphincter (LES) relaxation and inhibits progression of ongoing peristaltic contraction in the esophagus. Recent studies show that longitudinal muscle contraction of the esophagus may play a role in LES relaxation. Our goal was to determine whether a subthreshold pharyngeal stimulus induces contraction of the longitudinal muscle of the esophagus and to determine the nature of this contraction. Studies were conducted in 16 healthy subjects. High resolution manometry (HRM) recorded pressures, and high frequency intraluminal ultrasound (HFIUS) images recorded longitudinal muscle contraction at various locations in the esophagus. Subthreshold pharyngeal stimulation was induced by injection of minute amounts of water in the pharynx. A subthreshold pharyngeal stimulus induced strong contraction and caudal descent of the upper esophageal sphincter (UES) along with relaxation of the LES. HFIUS identified longitudinal muscle contraction of the proximal (3-5 cm below the UES) but not the distal esophagus. Pharyngeal stimulus, following a dry swallow, blocked the progression of dry swallow-induced peristalsis; this was also associated with UES contraction and descent along with the contraction of longitudinal muscle of the proximal esophagus. We identify a unique pattern of longitudinal muscle contraction of the proximal esophagus in response to subthreshold pharyngeal stimulus, which we propose may be responsible for relaxation of the distal esophagus and LES through the stretch sensitive activation of myenteric inhibitory motor neurons.

Anger, hostility, and aggression among Iraq and Afghanistan War veterans reporting PTSD and subthreshold PTSD.

PubMed

Jakupcak, Matthew; Conybeare, Daniel; Phelps, Lori; Hunt, Stephen; Holmes, Hollie A; Felker, Bradford; Klevens, Michele; McFall, Miles E

2007-12-01

Iraq and Afghanistan War veterans were grouped by level of posttraumatic stress disorder (PTSD) symptomatology and compared on self-report measures of trait anger, hostility, and aggression. Veterans who screened positive for PTSD reported significantly greater anger and hostility than those in the subthreshold-PTSD and non-PTSD groups. Veterans in the subthreshold-PTSD group reported significantly greater anger and hostility than those in the non-PTSD group. The PTSD and subthreshold-PTSD groups did not differ with respect to aggression, though both groups were significantly more likely to have endorsed aggression than the non-PTSD group. These findings suggest that providers should screen for anger and aggression among Iraq and Afghanistan War veterans who exhibit symptoms of PTSD and incorporate relevant anger treatments into early intervention strategies.

Heart rate response to fear conditioning and virtual reality in subthreshold PTSD.

PubMed

Roy, Michael J; Costanzo, Michelle E; Jovanovic, Tanja; Leaman, Suzanne; Taylor, Patricia; Norrholm, Seth D; Rizzo, Albert A

2013-01-01

Posttraumatic stress disorder (PTSD) is a significant health concern for U.S. military service members (SMs) returning from Afghanistan and Iraq. Early intervention to prevent chronic disability requires greater understanding of subthreshold PTSD symptoms, which are associated with impaired physical health, mental health, and risk for delayed onset PTSD. We report a comparison of physiologic responses for recently deployed SMs with high and low subthreshold PTSD symptoms, respectively, to a fear conditioning task and novel virtual reality paradigm (Virtual Iraq). The high symptom group demonstrated elevated heart rate (HR) response during fear conditioning. Virtual reality sequences evoked significant HR responses which predicted variance of the PTSD Checklist-Military Version self-report. Our results support the value of physiologic assessment during fear conditioning and combat-related virtual reality exposure as complementary tools in detecting subthreshold PTSD symptoms in Veterans.

A novel pattern of longitudinal muscle contraction with subthreshold pharyngeal stimulus: a possible mechanism of lower esophageal sphincter relaxation

PubMed Central

Leslie, Eric; Bhargava, Valmik

2012-01-01

A subthreshold pharyngeal stimulus induces lower esophageal sphincter (LES) relaxation and inhibits progression of ongoing peristaltic contraction in the esophagus. Recent studies show that longitudinal muscle contraction of the esophagus may play a role in LES relaxation. Our goal was to determine whether a subthreshold pharyngeal stimulus induces contraction of the longitudinal muscle of the esophagus and to determine the nature of this contraction. Studies were conducted in 16 healthy subjects. High resolution manometry (HRM) recorded pressures, and high frequency intraluminal ultrasound (HFIUS) images recorded longitudinal muscle contraction at various locations in the esophagus. Subthreshold pharyngeal stimulation was induced by injection of minute amounts of water in the pharynx. A subthreshold pharyngeal stimulus induced strong contraction and caudal descent of the upper esophageal sphincter (UES) along with relaxation of the LES. HFIUS identified longitudinal muscle contraction of the proximal (3–5 cm below the UES) but not the distal esophagus. Pharyngeal stimulus, following a dry swallow, blocked the progression of dry swallow-induced peristalsis; this was also associated with UES contraction and descent along with the contraction of longitudinal muscle of the proximal esophagus. We identify a unique pattern of longitudinal muscle contraction of the proximal esophagus in response to subthreshold pharyngeal stimulus, which we propose may be responsible for relaxation of the distal esophagus and LES through the stretch sensitive activation of myenteric inhibitory motor neurons. PMID:22173917

The Relationship Between Subthreshold Autistic Traits, Ambiguous Figure Perception and Divergent Thinking.

PubMed

Best, Catherine; Arora, Shruti; Porter, Fiona; Doherty, Martin

2015-12-01

This research investigates the paradox of creativity in autism. That is, whether people with subclinical autistic traits have cognitive styles conducive to creativity or whether they are disadvantaged by the implied cognitive and behavioural rigidity of the autism phenotype. The relationship between divergent thinking (a cognitive component of creativity), perception of ambiguous figures, and self-reported autistic traits was evaluated in 312 individuals in a non-clinical sample. High levels of autistic traits were significantly associated with lower fluency scores on the divergent thinking tasks. However autistic traits were associated with high numbers of unusual responses on the divergent thinking tasks. Generation of novel ideas is a prerequisite for creative problem solving and may be an adaptive advantage associated with autistic traits.

Geometric properties-dependent neural synchrony modulated by extracellular subthreshold electric field

NASA Astrophysics Data System (ADS)

Wei, Xile; Si, Kaili; Yi, Guosheng; Wang, Jiang; Lu, Meili

2016-07-01

In this paper, we use a reduced two-compartment neuron model to investigate the interaction between extracellular subthreshold electric field and synchrony in small world networks. It is observed that network synchronization is closely related to the strength of electric field and geometric properties of the two-compartment model. Specifically, increasing the electric field induces a gradual improvement in network synchrony, while increasing the geometric factor results in an abrupt decrease in synchronization of network. In addition, increasing electric field can make the network become synchronous from asynchronous when the geometric parameter is set to a given value. Furthermore, it is demonstrated that network synchrony can also be affected by the firing frequency and dynamical bifurcation feature of single neuron. These results highlight the effect of weak field on network synchrony from the view of biophysical model, which may contribute to further understanding the effect of electric field on network activity.

Near-thermal limit gating in heavily doped III-V semiconductor nanowires using polymer electrolytes

NASA Astrophysics Data System (ADS)

Ullah, A. R.; Carrad, D. J.; Krogstrup, P.; Nygârd, J.; Micolich, A. P.

2018-02-01

Doping is a common route to reducing nanowire transistor on-resistance but it has limits. A high doping level gives significant loss in gate performance and ultimately complete gate failure. We show that electrolyte gating remains effective even when the Be doping in our GaAs nanowires is so high that traditional metal-oxide gates fail. In this regime we obtain a combination of subthreshold swing and contact resistance that surpasses the best existing p -type nanowire metal-oxide semiconductor field-effect transistors (MOSFETs). Our subthreshold swing of 75 mV/dec is within 25 % of the room-temperature thermal limit and comparable with n -InP and n -GaAs nanowire MOSFETs. Our results open a new path to extending the performance and application of nanowire transistors, and motivate further work on improved solid electrolytes for nanoscale device applications.

Active subthreshold dendritic conductances shape the local field potential

PubMed Central

Ness, Torbjørn V.; Remme, Michiel W. H.

2016-01-01

Key points The local field potential (LFP), the low‐frequency part of extracellular potentials recorded in neural tissue, is often used for probing neural circuit activity. Interpreting the LFP signal is difficult, however.While the cortical LFP is thought mainly to reflect synaptic inputs onto pyramidal neurons, little is known about the role of the various subthreshold active conductances in shaping the LFP.By means of biophysical modelling we obtain a comprehensive qualitative understanding of how the LFP generated by a single pyramidal neuron depends on the type and spatial distribution of active subthreshold currents.For pyramidal neurons, the h‐type channels probably play a key role and can cause a distinct resonance in the LFP power spectrum.Our results show that the LFP signal can give information about the active properties of neurons and imply that preferred frequencies in the LFP can result from those cellular properties instead of, for example, network dynamics. Abstract The main contribution to the local field potential (LFP) is thought to stem from synaptic input to neurons and the ensuing subthreshold dendritic processing. The role of active dendritic conductances in shaping the LFP has received little attention, even though such ion channels are known to affect the subthreshold neuron dynamics. Here we used a modelling approach to investigate the effects of subthreshold dendritic conductances on the LFP. Using a biophysically detailed, experimentally constrained model of a cortical pyramidal neuron, we identified conditions under which subthreshold active conductances are a major factor in shaping the LFP. We found that, in particular, the hyperpolarization‐activated inward current, I h, can have a sizable effect and cause a resonance in the LFP power spectral density. To get a general, qualitative understanding of how any subthreshold active dendritic conductance and its cellular distribution can affect the LFP, we next performed a systematic study with a simplified model. We found that the effect on the LFP is most pronounced when (1) the synaptic drive to the cell is asymmetrically distributed (i.e. either basal or apical), (2) the active conductances are distributed non‐uniformly with the highest channel densities near the synaptic input and (3) when the LFP is measured at the opposite pole of the cell relative to the synaptic input. In summary, we show that subthreshold active conductances can be strongly reflected in LFP signals, opening up the possibility that the LFP can be used to characterize the properties and cellular distributions of active conductances. PMID:27079755

Subthreshold and threshold DSM-IV generalized anxiety disorder in Singapore: Results from a nationally representative sample.

PubMed

Lee, Siau Pheng; Sagayadevan, Vathsala; Vaingankar, Janhavi Ajit; Chong, Siow Ann; Subramaniam, Mythily

2015-05-01

Previous nationally representative studies have reported prevalence of DSM-IV generalized anxiety disorder (GAD). However, subthreshold and threshold GAD expressions remain poorly understood. The current study examined the prevalence, correlates and co-morbidity of a broader diagnosis of GAD in Singapore. The Singapore Mental Health Study (SMHS) was an epidemiological survey conducted in the population (N=6616) aged 18 years and older. The Composite International Diagnostic Interview version 3.0 (CIDI 3.0) was used to establish mental disorder diagnoses. The lifetime prevalence for subthreshold GAD (2.1%) and threshold GAD (1.5%) in the current sample was found to be lower than in Western populations. Younger age group, Indian ethnicity, previously married, chronic physical conditions, and being unemployed were associated with higher odds of having more severe expression of generalized anxiety. The relatively lower prevalence rate of subthreshold GAD expression suggests possible cultural interferences in the reporting and manifestation of anxiety symptomatology. Despite the low prevalence, significant impacts on functioning and comorbidity among subthreshold generalized anxiety cases indicate the importance of early treatment to ensure a better prognosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

Channel length scaling behavior in transistors based on individual versus dense arrays of carbon nanotubes

NASA Astrophysics Data System (ADS)

Brady, Gerald J.; Jinkins, Katherine R.; Arnold, Michael S.

2017-09-01

Recent advances in the solution-phase sorting and assembly of semiconducting single-walled carbon nanotubes (SWCNTs) have enabled significant gains in the performance of field-effect transistors (FETs) constructed from dense arrays of aligned SWCNTs. However, the channel length (LCH) downscaling behaviors of these arrays, which contain some organizational disorder (i.e., rotational misalignment and non-uniform pitch), have not yet been studied in detail below LCH of 100 nm. This study compares the behaviors of individualized SWCNTs with arrays of aligned, solution-cast SWCNTs in FETs with LCH ranging from 30 to 240 nm. The on-state conductance of both individual and array SWCNTs rises with decreasing LCH. Nearly ballistic transport is observed for LCH < 40 nm in both cases, reaching a conductance of 0.82 Go per SWCNT in arrays, where Go = 2e2/h is the quantum conductance. In the off-state, the off-current and subthreshold swing of the individual SWCNTs remain nearly invariant with decreasing LCH whereas array SWCNT FETs suffer from increasing off-state current and deteriorating subthreshold swing for LCH below 100 nm. We analyze array disorder using atomic force microscopy, which shows that crossing SWCNTs that arise from misoriented alignment raise SWCNTs off of the substrate for large portions of the channel when LCH is small. Electrostatics modeling analysis indicates that these raised SWCNTs are a likely contributor to the deteriorating off-current and subthreshold characteristics of arrays. These results demonstrate that improved inter-SWCNT pitch uniformity and alignment with minimal inter-SWCNT interactions will be necessary in order for solution processed SWCNT arrays to reach subthreshold performance on par with isolated SWCNTs. These results are also promising because they show that arrays of solution-processed SWCNTs can nearly reach ballistic conductance in the on-state despite imperfections in pitch and alignment.

Interaction of different antidepressants with acute and chronic methadone in mice, and possible clinical implications.

PubMed

Schreiber, Shaul; Barak, Yonatan; Hostovsky, Avner; Baratz-Goldstein, Renana; Volis, Ina; Rubovitch, Vardit; Pick, Chaim G

2014-04-01

We studied the interaction of a single dose of different antidepressant medications with a single (acute) dose or implanted mini-pump (chronic) methadone administration in mice, using the hotplate assay. For the acute experiment, subthreshold doses of six antidepressant drugs were administered separately with a single dose of methadone. The addition of a subthreshold dose of desipramine or clomipramine to methadone produced significant augmentation of the methadone effect with each drug (p < 0.05). Fluvoxamine given at a fixed subthreshold dose induced a synergistic effect only with a low methadone dose. Escitalopram, reboxetine and venlafaxine given separately, each at a fixed subthreshold dose, induced no interaction. Possible clinical implications of these findings are that while escitalopram, reboxetine and venlafaxine do not affect methadone's antinociception in mice and are safe to be given together with methadone when indicated, fluvoxamine, clomipramine and desipramine considerably augment methadone-induced effects and should be avoided in this population due to the risk of inducing opiate overdose. For the chromic experiment, when a subthreshold dose of either escitalopram, desipramine or clomipramine was injected to mice following 2 weeks of methadone administration with the mini-pump, none of the antidepressant drugs strengthened methadone's analgesic effect. Further studies are needed before possible clinical implications can be drawn.

Subthreshold IKK activation modulates the effector functions of primary mast cells and allows specific targeting of transformed mast cells

PubMed Central

Drube, Sebastian; Beyer, Mandy; Rothe, Mandy; Rabenhorst, Anja; Göpfert, Christiane; Meininger, Isabel; Diamanti, Michaela A.; Stegner, David; Häfner, Norman; Böttcher, Martin; Reinecke, Kirstin; Herdegen, Thomas; Greten, Florian R.; Nieswandt, Bernhard; Hartmann, Karin; Krämer, Oliver H.; Kamradt, Thomas

2015-01-01

Mast cell differentiation and proliferation depends on IL-3. IL-3 induces the activation of MAP-kinases and STATs and consequently induces proliferation and survival. Dysregulation of IL-3 signaling pathways also contribute to inflammation and tumorigenesis. We show here that IL-3 induces a SFK- and Ca2+-dependent activation of the inhibitor of κB kinases 2 (IKK2) which results in mast cell proliferation and survival but does not induce IκBα-degradation and NFκB activation. Therefore we propose the term “subthreshold IKK activation”. This subthreshold IKK activation also primes mast cells for enhanced responsiveness to IL-33R signaling. Consequently, co-stimulation with IL-3 and IL-33 increases IKK activation and massively enhances cytokine production induced by IL-33. We further reveal that in neoplastic mast cells expressing constitutively active Ras, subthreshold IKK activation is associated with uncontrolled proliferation. Consequently, pharmacological IKK inhibition reduces tumor growth selectively by inducing apoptosis in vivo. Together, subthreshold IKK activation is crucial to mediate the full IL-33-induced effector functions in primary mast cells and to mediate uncontrolled proliferation of neoplastic mast cells. Thus, IKK2 is a new molecularly defined target structure. PMID:25749030

Improving subthreshold swing to thermionic emission limit in carbon nanotube network film-based field-effect

NASA Astrophysics Data System (ADS)

Zhao, Chenyi; Zhong, Donglai; Qiu, Chenguang; Han, Jie; Zhang, Zhiyong; Peng, Lian-Mao

2018-01-01

In this letter, we explore the vertical scaling-down behavior of carbon nanotube (CNT) network film field-effect transistors (FETs) and show that by using a high-efficiency gate insulator, we can substantially improve the subthreshold swing (SS) and its uniformity. By using an HfO2 layer with a thickness of 7.3 nm as the gate insulator, we fabricated CNT network film FETs with a long channel (>2 μm) that exhibit an SS of approximately 60 mV/dec. The preferred thickness of HfO2 as the gate insulator in a CNT network FET is between 7 nm and 10 nm, simultaneously yielding an excellent SS (<80 mV/decade) and low gate leakage. However, because of the statistical fluctuations of the network CNT channel, the lateral scaling of CNT network film-based FETs is more difficult than that of conventional FETs. Experiments suggest that excellent SS is difficult to achieve statistically in CNT network film FETs with a small channel length (smaller than the mean length of the CNTs), which eventually limits the further scaling down of this kind of CNT FET to the sub-micrometer regime.

Improved organic thin-film transistor performance using novel self-assembled monolayers

NASA Astrophysics Data System (ADS)

McDowell, M.; Hill, I. G.; McDermott, J. E.; Bernasek, S. L.; Schwartz, J.

2006-02-01

Pentacene-based organic thin-film transistors have been fabricated using a phosphonate-linked anthracene self-assembled monolayer as a buffer between the silicon dioxide gate dielectric and the active pentacene channel region. Vast improvements in the subthreshold slope and threshold voltage are observed compared to control devices fabricated without the buffer. Both observations are consistent with a greatly reduced density of charge trapping states at the semiconductor-dielectric interface effected by introduction of the self-assembled monolayer.

[PTSD in young children after medical procedure].

PubMed

Sepers, J W; van der Boon, N; Landsmeer-Beker, N E A

2016-01-01

An eight-year-old boy with spastic type bilateral cerebral palsy and a two-year-old girl with biliary atresia were referred to a psycho-trauma centre. Both children developed post-traumatic stress disorder (PTSD) symptoms as a result of the medical procedure. Because of their symptoms, they were resisting further medical treatment. The children were given trauma-focused treatment (eye movement and desensitisation reprocessing and cognitive behavioural therapy). This article argues that hypnosis and distraction can play a role in preventing PTSD symptoms after undergoing a medical procedure. If PTSD is unavoidable, it is important to recognise the symptoms and to treat these children. Furthermore, their parents might also be traumatised. PTSD symptoms in children and their parents can be successfully treated. Also children with sub-threshold PTSD can benefit from trauma treatment.

The impact of stress on depressive symptoms is moderated by social support in Chinese adolescents with subthreshold depression: a multi-wave longitudinal study.

PubMed

Yang, Juan; Yao, Shuqiao; Zhu, Xiongzhao; Zhang, Chenchen; Ling, Yu; Abela, John R Z; Esseling, Petra G; McWhinnie, Chad

2010-12-01

Most studies have shown that negative life events and social support are important factors in the development and outcome of depression. It is unknown if these factors are important in adolescents with subthreshold depression. Thus, the current study examined whether high levels of social support from peers buffer adolescents exhibiting subthreshold depressive symptoms against experiencing further increases in such symptoms following the occurrence of negative events. Participants included 143 adolescents (aged 14 to 18; M=16.07, SD=.66) in Hunan Province China who were selected because they were exhibiting subthreshold depressive symptoms at the time of initial assessment. During an initial assessment, participants completed measures assessing social support from peers and depressive symptoms. Participants subsequently completed measures assessing depressive symptoms and the occurrence of negative events once every three months for the subsequent fifteen months. The prevalence of lifetime subthreshold depression in Hunan was 22.9% (n=143). The results of hierarchical linear modeling analyses indicated that lower levels of social support from peers was associated with greater increases in depressive symptoms following the occurrence of negative events. The results suggested that the association between the occurrence of negative events and increased depressive symptoms is moderated by social support from peers in adolescents with subthreshold depression in mainland China, in line with the buffering hypothesis. The adolescent sample used in the current study was from Hunan, China, which could limit the generalizability of our results to other populations. In addition, given that it is possible that cultural context shapes symptom manifestation, future research should assess a broader array of symptom outcomes. Copyright © 2010 Elsevier B.V. All rights reserved.

Similar Familial Underpinnings for Full and Subsyndromal Pediatric Bipolar Disorder: A Familial Risk Analysis

PubMed Central

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

2017-01-01

Objectives To examine the validity of subthreshold pediatric bipolar-I (BP-I) disorder, we compared the familial risk for BP-I disorder in child probands with full BP-I disorder, subthreshold BP-I disorder, ADHD, and non-ADHD/non-bipolar disorder controls. Methods Probands were youth ages 6–17 meeting criteria for BP-I disorder, full (N=239) or subthreshold (N=43), and their first degree relatives (N=687 and N=120, respectively). Comparators were youth with ADHD (N=162), controls (N=136), and their first-degree relatives (N=511 and N=411, respectively). We randomly selected 162 non-bipolar ADHD probands and 136 non-bipolar non-ADHD control probands of similar age and sex distribution to the BP-I probands from our case-control ADHD family studies. Psychiatric assessments were made by trained psychometricians using the KSADS-E and SCID structured diagnostic interviews. We analyzed rates of bipolar disorder using multinomial logistic regression. Results Rates of full bipolar-I disorder significantly differed between the four groups (χ23 = 32.72, p<0.001): relatives of full BP-I and relatives of subthreshold BP-I probands had significantly higher rates of full BP-I disorder than relatives of ADHD probands and relatives of control probands. Relatives of full BP-I, subthreshold BP-I, and ADHD probands also had significantly higher rates of major depressive disorder (MDD) compared to relatives of control probands. Conclusions Our results showed that youth with subthreshold BP-I disorder had similarly elevated risk for BP-I disorder and MDD in first-degree relatives as youth with full BP-I disorder. These findings support the diagnostic continuity between subsyndromal and fully syndromatic states of pediatric BP-I disorder. PMID:28544732

Sub-threshold standard cell library design for ultra-low power biomedical applications.

PubMed

Li, Ming-Zhong; Ieong, Chio-In; Law, Man-Kay; Mak, Pui-In; Vai, Mang-I; Martins, Rui P

2013-01-01

Portable/Implantable biomedical applications usually exhibit stringent power budgets for prolonging battery life time, but loose operating frequency requirements due to small bio-signal bandwidths, typically below a few kHz. The use of sub-threshold digital circuits is ideal in such scenario to achieve optimized power/speed tradeoffs. This paper discusses the design of a sub-threshold standard cell library using a standard 0.18-µm CMOS technology. A complete library of 56 standard cells is designed and the methodology is ensured through schematic design, transistor width scaling and layout design, as well as timing, power and functionality characterization. Performance comparison between our sub-threshold standard cell library and a commercial standard cell library using a 5-stage ring oscillator and an ECG designated FIR filter is performed. Simulation results show that our library achieves a total power saving of 95.62% and a leakage power reduction of 97.54% when compared with the same design implemented by the commercial standard cell library (SCL).

Panic disorder and subthreshold panic in the UK general population: epidemiology, comorbidity and functional limitation.

PubMed

Skapinakis, P; Lewis, G; Davies, S; Brugha, T; Prince, M; Singleton, N

2011-09-01

The epidemiology of panic disorder has not been investigated in the past in the UK using a nationally representative sample of the population. The aim of the present paper was to examine the epidemiology, comorbidity and functional impairment of subthreshold panic and panic disorder with or without agoraphobia. We used data from the 2000 Office for National Statistics Psychiatric Morbidity survey (N=8580). Panic disorder and agoraphobia were assessed with the Revised Clinical Interview Schedule (CIS-R). The prevalence of panic disorder with or without agoraphobia was 1.70% (95% confidence interval: 1.41-2.03%). Subthreshold panic was more common. Economic inactivity was consistently associated with all syndromes. The comorbidity pattern of the panic syndromes and the associated functional impairment show that panic-related conditions are important public health problems, even in subthreshold status. The findings show that efforts to reduce the disability associated with psychiatric disorders should include detection and management of panic disorder. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Major depressive and anxiety disorders in visually impaired older adults.

PubMed

van der Aa, Hilde P A; Comijs, Hannie C; Penninx, Brenda W J H; van Rens, Ger H M B; van Nispen, Ruth M A

2015-01-20

We assessed the prevalence of subthreshold depression and anxiety, and major depressive, dysthymic, and anxiety disorders (panic disorder, agoraphobia, social phobia, and general anxiety disorder) in visually impaired older adults and compared these estimates with those of normally sighted peers. Cross-sectional data were analyzed based on telephone interviews with visually impaired older adults aged ≥ 60 years (n = 615) with a visual acuity of ≥ 0.30 logMAR (20/40 Snellen) in the best eye from outpatient low vision rehabilitation centers, and face-to-face interviews with community-dwelling normally sighted peers (n = 1232). To determine prevalence rates, the normally sighted population was weighted on sex and age to fit the visually impaired population. Logistic regression analyses were used to compare the populations and to correct for confounders. The prevalence of major depressive disorder (5.4%) and anxiety disorders (7.5%), as well as the prevalence of subthreshold depression (32.2%) and subthreshold anxiety (15.6%), were significantly higher in visually impaired older adults compared to their normally sighted peers (P < 0.05). Agoraphobia and social phobia were the most prevalent anxiety disorders in visually impaired older adults. This study shows that depression and anxiety are major public health problems in visually impaired older adults. Research on psychotherapeutic and psychopharmacologic interventions to improve depression and anxiety in this population is warranted. (http://www.trialregister.nl number, NTR3296.). Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

Neurophysiological mechanism of possibly confounding peripheral activation of the facial nerve during corticobulbar tract monitoring.

PubMed

Téllez, Maria J; Ulkatan, Sedat; Urriza, Javier; Arranz-Arranz, Beatriz; Deletis, Vedran

2016-02-01

To improve the recognition and possibly prevent confounding peripheral activation of the facial nerve caused by leaking transcranial electrical stimulation (TES) current during corticobulbar tract monitoring. We applied a single stimulus and a short train of electrical stimuli directly to the extracranial portion of the facial nerve. We compared the peripherally elicited compound muscle action potential (CMAP) of the facial nerve with the responses elicited by TES during intraoperative monitoring of the corticobulbar tract. A single stimulus applied directly to the facial nerve at subthreshold intensities did not evoke a CMAP, whereas short trains of subthreshold stimuli repeatedly evoked CMAPs. This is due to the phenomenon of sub- or near-threshold super excitability of the cranial nerve. Therefore, the facial responses evoked by short trains TES, when the leaked current reaches the facial nerve at sub- or near-threshold intensity, could lead to false interpretation. Our results revealed a potential pitfall in the current methodology for facial corticobulbar tract monitoring that is due to the activation of the facial nerve by subthreshold trains of stimuli. This study proposes a new criterion to exclude peripheral activation during corticobulbar tract monitoring. The failure to recognize and avoid facial nerve activation due to leaking current in the peripheral portion of the facial nerve during TES decreases the reliability of corticobulbar tract monitoring by increasing the possibility of false interpretation. Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

LONG-TERM SD-OCT/SLO IMAGING OF NEURORETINA AND RETINAL PIGMENT EPITHELIUM AFTER SUB-THRESHOLD INFRARED LASER TREATMENT OF DRUSEN

PubMed Central

MOJANA, FRANCESCA; BRAR, MANPREET; CHENG, LINGYUN; BARTSCH, DIRK-UWE G.; FREEMAN, WILLIAM R.

2012-01-01

PURPOSE To determine the long-term effect of sub-threshold diode laser treatment for drusen in patients with non-exudative age-related macular degeneration (AMD) with spectral domain optical coherence tomography combined with simultaneous scanning laser ophthalmoscope (SD-OCT/SLO). METHODS 8 eyes of 4 consecutive AMD patients with bilateral drusen previously treated with sub-threshold diode laser were imaged with SD-OCT/SLO. Abnormalities in the outer retina layers reflectivity as seen with SD-OCT/SLO were retrospectively analyzed and compared with color fundus pictures and autofluorescence images (AF) acquired immediately before and after the laser treatment. RESULTS A focal discrete disruptions in the reflectivity of the outer retinal layers was noted in 29% of the laser lesions. The junction in between the inner and outer segment of the photoreceptor was more frequently affected, with associated focal damage of the outer nuclear layer. Defects of the RPE were occasionally detected. These changes did not correspond to threshold burns on color fundus photography, but corresponded to focal areas of increased AF in the majority of the cases. CONCLUSIONS Sub-threshold diode laser treatment causes long-term disruption of the retinal photoreceptor layer as analyzed by SD-OCT/SLO. The concept that sub-threshold laser treatment can achieve a selected RPE effect without damage to rods and cones may be flawed. PMID:21157398

SUBTHRESHOLD MICROPULSE DIODE LASER VERSUS CONVENTIONAL LASER PHOTOCOAGULATION FOR DIABETIC MACULAR EDEMA: A Meta-Analysis of Randomized Controlled Trials.

PubMed

Chen, Guohai; Tzekov, Radouil; Li, Wensheng; Jiang, Fangzheng; Mao, Sihong; Tong, Yuhua

2016-11-01

To evaluate the relative efficacy of subthreshold micropulse diode laser versus conventional laser photocoagulation for the treatment of diabetic macular edema. A comprehensive literature search was conducted to find relevant randomized controlled trials (RCTs). Efficacy estimates were determined by comparing weighted mean differences of the mean change of best-corrected visual acuity and central macular thickness from baseline. Six RCTs were selected for this meta-analysis, including 398 eyes (203 eyes in the subthreshold micropulse diode laser group and 195 eyes in the conventional laser group). Subthreshold micropulse diode laser was superior to conventional laser in terms of mean change of logMAR best-corrected visual acuity at 3, 9, and 12 months after treatment (P = 0.02; P = 0.04, and P = 0.03, respectively), and it showed a similar trend at 6 months (P = 0.05). Although, there was no significant difference in terms of mean change in central macular thickness from baseline to 3, 6, 9, or 12 months (P = 0.80; P = 0.20; P = 0.88, and P = 0.86, respectively). Subthreshold micropulse diode laser treatment resulted in better visual acuity compared with conventional laser, although the differences before 12 months are likely to be too small to be of clinical relevance and may be dependent on baseline best-corrected visual acuity. The two types of treatment seem to have similar anatomical outcome.

Information transmission in hippocampal CA1 neuron models in the presence of poisson shot noise: the case of periodic sub-threshold spike trains.

PubMed

Kawaguchi, Minato; Mino, Hiroyuki; Durand, Dominique M

2006-01-01

This article presents an analysis of the information transmission of periodic sub-threshold spike trains in a hippocampal CA1 neuron model in the presence of a homogeneous Poisson shot noise. In the computer simulation, periodic sub-threshold spike trains were presented repeatedly to the midpoint of the main apical branch, while the homogeneous Poisson shot noise was applied to the mid-point of a basal dendrite in the CA1 neuron model consisting of the soma with one sodium, one calcium, and five potassium channels. From spike firing times recorded at the soma, the inter spike intervals were generated and then the probability, p(T), of the inter-spike interval histogram corresponding to the spike interval, r, of the periodic input spike trains was estimated to obtain an index of information transmission. In the present article, it is shown that at a specific amplitude of the homogeneous Poisson shot noise, p(T) was found to be maximized, as well as the possibility to encode the periodic sub-threshold spike trains became greater. It was implied that setting the amplitude of the homogeneous Poisson shot noise to the specific values which maximize the information transmission might contribute to efficiently encoding the periodic sub-threshold spike trains by utilizing the stochastic resonance.

Subthreshold concentration of endothelin-1-enhanced, capsaicin-induced bronchoconstriction in anaesthetized guinea-pigs.

PubMed

Kanazawa, H; Fujiwara, H; Hirata, K; Yoshikawa, J

1998-12-01

An increasing number of studies have been performed to address a possible role for endothelin-1 (ET-1) as a significant mediator in asthma. However, the effects of subthreshold concentrations of ET-1, which cannot elicit bronchial smooth muscle contraction itself, in asthma has yet to be determined. This study determined these effects of ET-1 on capsaicin-induced bronchoconstriction in anaesthetized guinea-pigs. Aerosolized ET-1 administered at doses of 10(-9) M and higher induced a dose-dependent increase in pulmonary resistance, but ET-1 at 10(-10) M did not have any bronchoconstrictive effect. However, this subthreshold concentration of ET-1 potentiated capsaicin-induced bronchoconstriction. In addition, the potentiation of capsaicin-induced bronchoconstriction by this subthreshold concentration of ET-1 was completely abolished by BQ788 (ET(B) receptor antagonist), but not BQ123 (ET(A) receptor antagonists). Immunoreactive substance P (SP) levels in bronchoalveolar lavage fluid after capsaicin administration were significantly higher than those after solvent administration. However, ET-1 alone did not significantly stimulate immunoreactive SP release and ET-1 (10(-10) M) did not potentiate capsaicin-induced immunoreactive SP release. In contrast, ET-1 (10(-10) M) potentiated exogenous neurokinin A- and SP-induced bronchoconstriction. These findings suggest that a subthreshold concentration of endothelin-1 does not potentiate the tachykinin release induced by capsaicin but the airway smooth muscle contraction through endothelin-B receptors.

Suicide Risk, Stress Sensitivity, and Self-Esteem among Young Adults Reporting Auditory Hallucinations.

PubMed

DeVylder, Jordan E; Hilimire, Matthew R

2015-08-01

Individuals with subthreshold psychotic experiences are at increased risk for suicidal thoughts and behavior, similar to those with schizophrenia and other psychotic disorders. This may be explained by shared risk factors such as heightened stress sensitivity or low self-esteem. Understanding the nature of this relationship could inform suicide prevention in social work practice. In this study, authors examined the relationship between self-reported auditory hallucinations and suicidal thoughts, plans, and attempts, in a nonclinical sample of young adults, controlling for scores on the Psychological Stress Index and Rosenberg Self-Esteem Scale. Auditory hallucinations were associated with approximately double the odds of suicidal ideation and plans and four times the odds for suicide attempts. This relationship was not explained by stress sensitivity or self-esteem, which were independently related to hallucinations and suicidality, respectively. Subthreshold auditory hallucinations may be a useful indicator of suicide risk. This association may represent a clinically significant relationship that may be addressed through social work interventions intended to alleviate stress sensitivity or improve self-esteem.

Comparative investigation of novel hetero gate dielectric and drain engineered charge plasma TFET for improved DC and RF performance

NASA Astrophysics Data System (ADS)

Yadav, Dharmendra Singh; Verma, Abhishek; Sharma, Dheeraj; Tirkey, Sukeshni; Raad, Bhagwan Ram

2017-11-01

Tunnel-field-effect-transistor (TFET) has emerged as one of the most prominent devices to replace conventional MOSFET due to its ability to provide sub-threshold slope below 60 mV/decade (SS ≤ 60 mV/decade) and low leakage current. Despite this, TFETs suffer from ambipolar behavior, lower ON-state current, and poor RF performance. To address these issues, we have introduced drain and gate work function engineering with hetero gate dielectric for the first time in charge plasma based doping-less TFET (DL TFET). In this, the usage of dual work functionality over the drain region significantly reduces the ambipolar behavior of the device by varying the energy barrier at drain/channel interface. Whereas, the presence of dual work function at the gate terminal increases the ON-state current (ION). The combined effect of dual work function at the gate and drain electrode results in the increment of ON-state current (ION) and decrement of ambipolar conduction (Iambi) respectively. Furthermore, the incorporation of hetero gate dielectric along with dual work functionality at the drain and gate electrode provides an overall improvement in the performance of the device in terms of reduction in ambipolarity, threshold voltage and sub-threshold slope along with improved ON-state current and high frequency figures of merit.

Palladium Gate All Around - Hetero Dielectric -Tunnel FET based highly sensitive Hydrogen Gas Sensor

NASA Astrophysics Data System (ADS)

Madan, Jaya; Chaujar, Rishu

2016-12-01

The paper presents a novel highly sensitive Hetero-Dielectric-Gate All Around Tunneling FET (HD-GAA-TFET) based Hydrogen Gas Sensor, incorporating the advantages of band to band tunneling (BTBT) mechanism. Here, the Palladium supported silicon dioxide is used as a sensing media and sensing relies on the interaction of hydrogen with Palladium-SiO2-Si. The high surface to volume ratio in the case of cylindrical GAA structure enhances the fortuities for surface reactions between H2 gas and Pd, and thus improves the sensitivity and stability of the sensor. Behaviour of the sensor in presence of hydrogen and at elevated temperatures is discussed. The conduction path of the sensor which is dependent on sensors radius has also been varied for the optimized sensitivity and static performance analysis of the sensor where the proposed design exhibits a superior performance in terms of threshold voltage, subthreshold swing, and band to band tunneling rate. Stability of the sensor with respect to temperature affectability has also been studied, and it is found that the device is reasonably stable and highly sensitive over the bearable temperature range. The successful utilization of HD-GAA-TFET in gas sensors may open a new door for the development of novel nanostructure gas sensing devices.

Major Depressive Disorder in Adolescence: The Role of Subthreshold Symptoms

ERIC Educational Resources Information Center

Georgiades, Katholiki; Lewinsohn, Peter M.; Monroe, Scott M.; Seeley, John R.

2006-01-01

Objective: To examine the longitudinal association between individual subthreshold symptoms and onset of major depressive disorder (MDD) in adolescence. Method: Data for analysis come from the Oregon Adolescent Depression Project, a prospective epidemiological study of psychological disorders among adolescents, ages 14 to 18 years, from the…

Prescription Pain Reliever Abuse and Dependence among Adolescents: A Nationally Representative Study

ERIC Educational Resources Information Center

Wu, Li-Tzy; Ringwalt, Christopher L.; Mannelli, Paolo; Patkar, Ashwin A.

2008-01-01

The study investigates the prevalence, patterns, and correlates of adolescents' abuse, sub-threshold dependence, and dependence on prescription pain relievers (PPRs) in a nationally representative sample. Results show dependence on PPRs can take place without abuse and that sub-threshold dependence could have implications for major diagnostic…

Reducing depression during the menopausal transition with health coaching: Results from the healthy menopausal transition randomised controlled trial.

PubMed

Almeida, Osvaldo P; Marsh, Kylie; Murray, Karen; Hickey, Martha; Sim, Moira; Ford, Andrew; Flicker, Leon

2016-10-01

To determine if health coaching (HC) decreases the incidence of depression, reduces the severity of symptoms, and increases quality of life during the menopausal transition (MT). Parallel, single-blinded, randomised controlled trial of 6 sessions of phone-delivered HC compared with usual care. Participants were 351 community-dwelling women free of major depression going through the MT, of whom 180 were assigned the intervention and 171 usual care. The primary outcome of interest was the incidence of clinically significant depressive symptoms over 52 weeks. Other study measures included the Hospital Anxiety and Depression Scale, quality of life (SF-12), the Menopause Rating Scale (MRS), diet, body mass index, alcohol use, smoking and physical activity. We considered that women with Patient Health Questionnaire (PHQ-9) scores between 5 and 14 (inclusive) had sub-threshold depressive symptoms. Nine women developed clinically significant symptoms of depression during the study-2 had been assigned HC (odds ratio, OR=0.26, 95%CI=0.05, 1.29; p=0.099). Intention-to-treat showed that, compared with usual care, the intervention led to a greater decline in depressive scores, most markedly for participants with sub-threshold depressive symptoms. Similar, but less pronounced, benefits were noticed for anxiety scores and the mental component summary of the SF-12. The intervention led to a decline in MRS scores by week 26 and subtle improvements in body mass, consumption of vegetables and smoking. HC addressing relevant risk factors for depression during the MT improves mental health measures. Our findings indicate that women with sub-threshold depressive symptoms may benefit the most from such interventions, and suggest that HC could play a useful role in minimizing mental health disturbance for women going through the MT. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Accurate analytical modeling of junctionless DG-MOSFET by green's function approach

NASA Astrophysics Data System (ADS)

Nandi, Ashutosh; Pandey, Nilesh

2017-11-01

An accurate analytical model of Junctionless double gate MOSFET (JL-DG-MOSFET) in the subthreshold regime of operation is developed in this work using green's function approach. The approach considers 2-D mixed boundary conditions and multi-zone techniques to provide an exact analytical solution to 2-D Poisson's equation. The Fourier coefficients are calculated correctly to derive the potential equations that are further used to model the channel current and subthreshold slope of the device. The threshold voltage roll-off is computed from parallel shifts of Ids-Vgs curves between the long channel and short-channel devices. It is observed that the green's function approach of solving 2-D Poisson's equation in both oxide and silicon region can accurately predict channel potential, subthreshold current (Isub), threshold voltage (Vt) roll-off and subthreshold slope (SS) of both long & short channel devices designed with different doping concentrations and higher as well as lower tsi/tox ratio. All the analytical model results are verified through comparisons with TCAD Sentaurus simulation results. It is observed that the model matches quite well with TCAD device simulations.

Long-term follow-up study of patients with refractory obsessive-compulsive disorder.

PubMed

Ross, Stephen; Fallon, Brian A; Petkova, Eva; Feinstein, Suzanne; Liebowitz, Michael R

2008-01-01

The authors prospectively followed patients with treatment-resistant obsessive-compulsive disorder (OCD). Between 1988 and 1995, 56 patients with a history of inadequate response to oral clomipramine received 14 infusions of intravenous clomipramine. The follow-up period ranged from 4 to 11 years after treatment. Of the 44 subjects interviewed at follow-up, 70.5% had current OCD and 29.5% had sub-threshold OCD. Almost half reported feeling much improved or very much improved compared to their state prior to treatment with intravenous clomipramine.

Near-zero hysteresis and near-ideal subthreshold swing in h-BN encapsulated single-layer MoS2 field-effect transistors

NASA Astrophysics Data System (ADS)

Vu, Quoc An; Fan, Sidi; Hyup Lee, Sang; Joo, Min-Kyu; Jong Yu, Woo; Lee, Young Hee

2018-07-01

While two-dimensional (2D) van der Waals (vdW) layered materials are promising channel materials for wearable electronics and energy-efficient field-effect transistors (FETs), large hysteresis and large subthreshold swing induced by either dangling bonds at gate oxide dielectrics and/or trap molecules in bubbles at vdW interface are a serious drawback, hampering implementation of the 2D-material based FETs in real electronics. Here, we report a monolayer MoS2 FET with near-zero hysteresis reaching 0.15% of the sweeping range of the gate bias, a record-value observed so far in 2D FETs. This was realized by squeezing the MoS2 channel between top h-BN layer and bottom h-BN gate dielectrics and further removing the trap molecules in bubbles at the vdW interfaces via post-annealing. By segregating the bubbles out to the edge of the channel, we also obtain excellent switching characteristics with a minimum subthreshold swing of 63 mV/dec, an average subthreshold slope of 69 mV/dec for a current range of four orders of magnitude at room temperature, and a high on/off current ratio of 108 at a small operating voltage (<1 V). Such a near-zero hysteresis and a near-ideal subthreshold limit originate from the reduced trap density of ~5.2  ×  109 cm‑2 eV‑1, a thousand times smaller than previously reported values.

Subthreshold membrane potential oscillations in inferior olive neurons are dynamically regulated by P/Q- and T-type calcium channels: a study in mutant mice.

PubMed

Choi, Soonwook; Yu, Eunah; Kim, Daesoo; Urbano, Francisco J; Makarenko, Vladimir; Shin, Hee-Sup; Llinás, Rodolfo R

2010-08-15

The role of P/Q- and T-type calcium channels in the rhythmic oscillatory behaviour of inferior olive (IO) neurons was investigated in mutant mice. Mice lacking either the CaV2.1 gene of the pore-forming alpha1A subunit for P/Q-type calcium channel, or the CaV3.1 gene of the pore-forming alpha1G subunit for T-type calcium channel were used. In vitro intracellular recording from IO neurons reveals that the amplitude and frequency of sinusoidal subthreshold oscillations (SSTOs) were reduced in the CaV2.1-/- mice. In the CaV3.1-/- mice, IO neurons also showed altered patterns of SSTOs and the probability of SSTO generation was significantly lower (15%, 5 of 34 neurons) than that of wild-type (78%, 31 of 40 neurons) or CaV2.1-/- mice (73%, 22 of 30 neurons). In addition, the low-threshold calcium spike and the sustained endogenous oscillation following rebound potentials were absent in IO neurons from CaV3.1-/- mice. Moreover, the phase-reset dynamics of oscillatory properties of single neurons and neuronal clusters in IO were remarkably altered in both CaV2.1-/- and CaV3.1-/- mice. These results suggest that both alpha1A P/Q- and alpha1G T-type calcium channels are required for the dynamic control of neuronal oscillations in the IO. These findings were supported by results from a mathematical IO neuronal model that incorporated T and P/Q channel kinetics.

Cocaine enhances the conditioned rewarding effects of MDMA in adolescent mice.

PubMed

Aguilar, M A; Roger-Sánchez, C; Rodríguez-Arias, M; Miñarro, J

2015-04-01

Although the consumption of cocaine is frequent in young users of MDMA (3,4-methylenedioxymethamphetamine), the influence of exposure to cocaine on the rewarding effects of MDMA in adolescents has not been studied. The purpose of the present work was to evaluate the effect of co-administration of cocaine (1 and 10 mg/kg) and a sub-threshold dose of MDMA (1.25 mg/kg) on the acquisition of conditioned place preference (CPP) (experiment 1). In addition, the effect of pre-treatment with cocaine on MDMA-induced CPP was evaluated (experiment 2). Levels of monoamines in striatum, hippocampus and cortex were measured in both experiments. Our hypotheses were that cocaine co-administration or pre-treatment would increase the rewarding effects of MDMA, and that these effects would be related with changes in brain monoamine levels. Our results showed that cocaine potentiated the rewarding effects of MDMA, since a sub-threshold dose of MDMA, which did not induce CPP by itself, induced a significant CPP in adolescent mice when administered along with cocaine during conditioning (experiment 1). Moreover, pre-treatment with cocaine several days before conditioning also increased the rewarding effects of MDMA (experiment 2). No significant changes in the levels of biogenic amines, which correlated with these behavioural effects, were observed. Our results confirm the involvement of the dopaminergic system in MDMA-induced CPP in adolescent mice and suggest that combined consumption with or pre-exposure to cocaine increases the conditioned rewarding effects of MDMA, which may enhance the capacity of MDMA to induce dependence. Copyright © 2015 Elsevier Inc. All rights reserved.

Alpha-Band Brain Oscillations Shape the Processing of Perceptible as well as Imperceptible Somatosensory Stimuli during Selective Attention.

PubMed

Forschack, Norman; Nierhaus, Till; Müller, Matthias M; Villringer, Arno

2017-07-19

Attention filters and weights sensory information according to behavioral demands. Stimulus-related neural responses are increased for the attended stimulus. Does alpha-band activity mediate this effect and is it restricted to conscious sensory events (suprathreshold), or does it also extend to unconscious stimuli (subthreshold)? To address these questions, we recorded EEG in healthy male and female volunteers undergoing subthreshold and suprathreshold somatosensory electrical stimulation to the left or right index finger. The task was to detect stimulation at the randomly alternated cued index finger. Under attention, amplitudes of somatosensory evoked potentials increased 50-60 ms after stimulation (P1) for both suprathreshold and subthreshold events. Prestimulus amplitude of peri-Rolandic alpha, that is mu, showed an inverse relationship to P1 amplitude during attention compared to when the finger was unattended. Interestingly, intermediate and high amplitudes of mu rhythm were associated with the highest P1 amplitudes during attention and smallest P1 during lack of attention, that is, these levels of alpha rhythm seemed to optimally support the behavioral goal ("detect" stimuli at the cued finger while ignoring the other finger). Our results show that attention enhances neural processing for both suprathreshold and subthreshold stimuli and they highlight a rather complex interaction between attention, Rolandic alpha activity, and their effects on stimulus processing. SIGNIFICANCE STATEMENT Attention is crucial in prioritizing processing of relevant perceptible (suprathreshold) stimuli: it filters and weights sensory input. The present study investigates the controversially discussed question whether this attention effect extends to imperceptible (subthreshold) stimuli as well. We found noninvasive EEG signatures for attentional modulation of neural events following perceptible and imperceptible somatosensory stimulation in human participants. Specifically, stimulus processing for both kinds of stimulation, subthreshold and suprathreshold, is enhanced by attention. Interestingly, Rolandic alpha rhythm strength and its influence on stimulus processing are strikingly altered by attention most likely to optimally achieve the behavioral goal. Copyright © 2017 the authors 0270-6474/17/376983-12$15.00/0.

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

PubMed

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

2017-05-01

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

Temperament and prodromal symptoms prior to first manic/hypomanic episodes: results from a pilot study.

PubMed

Zeschel, Eike; Bingmann, Tiffany; Bechdolf, Andreas; Krüger-Oezguerdal, Seza; Correll, Christoph U; Leopold, Karolina; Pfennig, Andrea; Bauer, Michael; Juckel, Georg

2015-03-01

Prodromal symptoms prior to first episode mania/hypomania have been reported. However, the relationship between temperament and manic/hypomanic prodromal symptoms has not been investigated. We hypothesized that subjects scoring higher on cyclothymic and irritable temperament scales show more manic/hypomanic prodromal symptoms. Euthymic patients diagnosed with bipolar-I or -II disorder within 8 years underwent retrospective assessments with the Temperament Evaluation of Memphis, Pisa, Paris and San Diego-autoquestionnaire (TEMPS-A) and the Bipolar Prodrome Symptom Scale-Retrospective (BPSS-R). Among 39 subjects (36.1 ± 9.9 years, females = 59%, bipolar-I = 62%) 100% and 92.3% reported subthreshold mania (mean = 7.4 ± 2.9) or subthreshold depressive symptoms (mean = 2.4 ± 1.5), and 87.2% and 43.6% reported general psychopathology (mean = 3.2 ± 2.0) or subthreshold psychotic symptoms (mean = 0.7 ± 1.0) prior to their first hypo-/manic episode. Subjects with higher cyclothymic and irritable temperament scores showed more subthreshold symptoms prior to the first manic/hypomanic episode, mainly subthreshold hypo-/manic symptoms (cyclothymic temperament r = 0.430; p = 0.006; irritable temperament r = 0.330; p = 0.040), general psychopathology symptoms (cyclothymic temperament r = 0.316; p = 0.05; irritable temperament r = 0.349; p = 0.029) and subthreshold psychotic symptoms (cyclothymic temperament r = 0.413; p = 0.009). In regression analyses, cyclothymic temperament explained 16.1% and 12.5% of the variance of the BPSS-R total score (p = 0.045) and psychosis subscore (p = 0.029). Retrospective study, no control group, small sample size. We present data, which indicate a relationship between cyclothymic and irritable temperament and prodromal symptoms prior to the first manic/hypomanic episode. These findings support the notion that assessing cyclothymic temperament to identify people at-risk of developing bipolar-I and -II disorder may help to increase the predictive validity of applied at-risk criteria. Copyright © 2014 Elsevier B.V. All rights reserved.

Cardiac Risk and Disordered Eating: Decreased R Wave Amplitude in Women with Bulimia Nervosa and Women with Subclinical Binge/Purge Symptoms.

PubMed

Green, Melinda; Rogers, Jennifer; Nguyen, Christine; Blasko, Katherine; Martin, Amanda; Hudson, Dominique; Fernandez-Kong, Kristen; Kaza-Amlak, Zauditu; Thimmesch, Brandon; Thorne, Tyler

2016-11-01

The purpose of the present study was threefold. First, we examined whether women with bulimia nervosa (n = 12) and women with subthreshold binge/purge symptoms (n = 20) showed decreased mean R wave amplitude, an indicator of cardiac risk, on electrocardiograph compared to asymptomatic women (n = 20). Second, we examined whether this marker was pervasive across experimental paradigms, including before and after sympathetic challenge tasks. Third, we investigated behavioural predictors of this marker, including binge frequency and purge frequency assessed by subtype (dietary restriction, excessive exercise, self-induced vomiting, and laxative abuse). Results of a 3 (ED symptom status) × 5 (experimental condition) mixed factorial ANCOVA (covariates: body mass index, age) indicated women with bulimia nervosa and women with subclinical binge/purge symptoms demonstrated significantly reduced mean R wave amplitude compared to asymptomatic women; this effect was pervasive across experimental conditions. Multiple regression analyses showed binge and purge behaviours, most notably laxative abuse as a purge method, predicted decreased R wave amplitude across all experimental conditions. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.

Diagnostic criteria for psychosomatic research and somatic symptom disorders.

PubMed

Sirri, Laura; Fava, Giovanni A

2013-02-01

The Diagnostic Criteria for Psychosomatic Research (DCPR) were introduced in 1995 by an international group of investigators to expand the traditional domains of the disease model. The DCPR are a set of 12 'psychosomatic syndromes' which provide operational tools for psychosocial variables with prognostic and therapeutic implications in clinical settings. Eight syndromes concern the main manifestations of abnormal illness behaviour: somatization, hypochondriacal fears and beliefs, and illness denial. The other four syndromes (alexithymia, type A behaviour, demoralization and irritable mood) refer to the domain of psychological factors affecting medical conditions. This review describes the conceptual bases of the DCPR and the main findings concerning their application, with particular reference to the incremental information they added to the customary psychiatric classification. The DCPR were also compared with the provisional DSM-5 somatic symptom disorders. The DCPR were found to be more sensitive than DSM-IV in identifying subthreshold psychological distress and characterizing patients' psychological response to medical illness. DSM-5 somatic symptom disorders seem to neglect important clinical phenomena, such as illness denial, resulting in a narrow view of patients' functioning. The additional information provided by the DCPR may enhance the decision-making process.

Attentional bias modification (ABM) training induces spontaneous brain activity changes in young women with subthreshold depression: a randomized controlled trial.

PubMed

Li, H; Wei, D; Browning, M; Du, X; Zhang, Q; Qiu, J

2016-04-01

Attention bias modification (ABM) training has been suggested to effectively reduce depressive symptoms, and may be useful in the prevention of the illness in individuals with subthreshold symptoms, yet little is known about the spontaneous brain activity changes associated with ABM training. Resting-state functional MRI was used to explore the effects of ABM training on subthreshold depression (SubD) and corresponding spontaneous brain activity changes. Participants were 41 young women with SubD and 26 matched non-depressed controls. Participants with SubD were randomized to receive either ABM or placebo training during 28 sessions across 4 weeks. Non-depressed controls were assessed before training only. Attentional bias, depressive severity, and spontaneous brain activity before and after training were assessed in both training groups. Findings revealed that compared to active control training, ABM training significantly decreased depression symptoms, and increased attention for positive stimuli. Resting-state data found that ABM training significantly reduced amplitude of low-frequency fluctuations (ALFF) of the right anterior insula (AI) and right middle frontal gyrus which showed greater ALFF than non-depressed controls before training; Functional connectivity strength between right AI and the right frontoinsular and right supramarginal gyrus were significantly decreased after training within the ABM group; moreover, the improvement of depression symptoms following ABM significantly correlated with the connectivity strength reductions between right AI and right frontoinsular and right supramarginal gyrus. These results suggest that ABM has the potential to reshape the abnormal patterns of spontaneous brain activity in relevant neural circuits associated with depression.

Reading Disability Spectrum: Early and Late Recognition, Subthreshold, and Full Comorbidity

ERIC Educational Resources Information Center

Töro, Krisztina Tárnokiné; Miklósi, Mónika; Horanyi, Eszter; Kovács, Gábor Pers; Balázs, Judit

2018-01-01

Several studies have reported high comorbidity for reading disability (RD) and psychiatric disorders. The aim of this study was to investigate the comorbidity of subthreshold and full psychiatric disorders with RD while comparing subgroups based on age of RD recognition (early vs. late). We analyzed data from 130 children with RD and 82 typically…

Effects of behavioral activation on default mode network connectivity in subthreshold depression: A preliminary resting-state fMRI study.

PubMed

Yokoyama, Satoshi; Okamoto, Yasumasa; Takagaki, Koki; Okada, Go; Takamura, Masahiro; Mori, Asako; Shiota, Syouichi; Ichikawa, Naho; Jinnin, Ran; Yamawaki, Shigeto

2018-02-01

Subthreshold depression is a risk factor for major depressive disorder, and it is known to have a negative impact on quality of life (QOL). Although behavioral activation, which is one type of cognitive behavioral therapy, is an effective psychological intervention for subthreshold depression, neural mechanisms of behavioral activation are unclear. Enhanced functional connectivity between default mode network (DMN) and the other regions has been demonstrated in participants with subthreshold depression. The purpose of this study was to examine the effects of behavioral activation on DMN abnormalities by using resting-state functional MRI (rs-fMRI). Participants with subthreshold depression (N =40) were randomly assigned to either an intervention group or a non-intervention group. They were scanned using rs-fMRI before and after the intervention. Independent component analysis indicated three subnetworks of the DMN. Analyzing intervention effects on functional connectivity of each subnetwork indicated that connectivity of the anterior DMN subnetwork with the dorsal anterior cingulate was reduced after the intervention. Moreover, this reduction was correlated with an increase in health-related QOL. We did not compare the findings with healthy participants. Further research should be conducted by including healthy controls to verify the results of this study. Mechanisms of behavioral activation might be related to enhanced ability to independently use the dACC and the DMN, which increases an attention control to positive external stimuli. This is the first study to investigate neural mechanisms of behavioral activation using rs-fMRI. Copyright © 2017 Elsevier B.V. All rights reserved.

Gender Differences in Neural Responses to Perceptually Invisible Fearful Face—An ERP Study

PubMed Central

Lee, Seung A.; Kim, Chai-Youn; Shim, Miseon; Lee, Seung-Hwan

2017-01-01

Women tend to respond to emotional stimuli differently from men. This study aimed at investigating whether neural responses to perceptually “invisible” emotional stimuli differ between men and women by exploiting event-related potential (ERP). Forty healthy participants (21 women) were recruited for the main experiment. A control experiment was conducted by excluding nine (7 women) participants from the main experiment and replacing them with additional ten (6 women) participants (total 41 participants) where Beck's Anxiety Inventory (BAI) and Beck's Depression Inventory (BDI) scores were controlled. Using the visual backward masking paradigm, either a fearful or a neutral face stimulus was presented in varied durations (subthreshold, near-threshold, or suprathreshold) followed by a mask. Participants performed a two-alternative forced choice (2-AFC) emotion discrimination task on each face. Behavioral analysis showed that participants were unaware of masked stimuli of which duration was the shortest and, therefore, processed at subthreshold. Nevertheless, women showed significantly larger response in P100 amplitude to subthreshold fearful faces than men. This result remained consistent in the control experiment. Our findings indicate gender-differences in neural response to subthreshold emotional face, which is reflected in the early processing stage. PMID:28184189

The most likely voltage path and large deviations approximations for integrate-and-fire neurons.

PubMed

Paninski, Liam

2006-08-01

We develop theory and numerical methods for computing the most likely subthreshold voltage path of a noisy integrate-and-fire (IF) neuron, given observations of the neuron's superthreshold spiking activity. This optimal voltage path satisfies a second-order ordinary differential (Euler-Lagrange) equation which may be solved analytically in a number of special cases, and which may be solved numerically in general via a simple "shooting" algorithm. Our results are applicable for both linear and nonlinear subthreshold dynamics, and in certain cases may be extended to correlated subthreshold noise sources. We also show how this optimal voltage may be used to obtain approximations to (1) the likelihood that an IF cell with a given set of parameters was responsible for the observed spike train; and (2) the instantaneous firing rate and interspike interval distribution of a given noisy IF cell. The latter probability approximations are based on the classical Freidlin-Wentzell theory of large deviations principles for stochastic differential equations. We close by comparing this most likely voltage path to the true observed subthreshold voltage trace in a case when intracellular voltage recordings are available in vitro.

Interactions between radiation and amphetamine in taste-aversion learning and the role of the area postrema in amphetamine-induced conditioned taste aversions

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

Rabin, B.M.; Hunt, W.A.; Lee, J.

1987-01-01

Three experiments were run to assess the role of the area postrema in taste-aversion learning resulting from combined treatment with subthreshold unconditioned stimuli and in the acquisition of an amphetamine-induced taste aversion. In the first experiment, it was shown that combined treatment with subthreshold radiation (15 rad) and subthreshold amphetamine (0.5 mg/kg, IP) resulted in the acquisition of a taste aversion. The second experiment showed that lesions of the area postrema blocked taste aversion learning produced by two subthreshold doses of amphetamine. In the third experiment, which looked at the dose-response curve for amphetamine-induced taste aversion learning to intact ratsmore » and rats with area postrema lesions, it was shown that both groups of rats acquired taste aversions following injection of amphetamine, although the rats with lesions showed a less-severe aversion than the intact rats. The results are interpreted as indicating that amphetamine-induced taste-aversion learning may involve area post-remamediated mechanisms, particularly at the lower doses, but an intact area postrema is not a necessary condition of the acquisition of an amphetamine-induced taste aversion.« less

Interactions between radiation and amphetamine in taste aversion learning and the role of the area postrema in amphetamine-induced conditioned taste aversions

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

Rabin, B.M.; Hunt, W.A.; Lee, J.

1987-08-01

Three experiments were run to assess the role of the area postrema in taste aversion learning resulting from combined treatment with subthreshold unconditioned stimuli and in the acquisition of an amphetamine-induced taste aversion. In the first experiment, it was shown that combined treatment with subthreshold radiation (15 rad) and subthreshold amphetamine (0.5 mg/kg, IP) resulted in the acquisition of a taste aversion. The second experiment showed that lesions of the area postrema blocked taste aversion learning produced by two subthreshold doses of amphetamine. In the third experiment, which looked at the dose-response curve for amphetamine-induced taste aversion learning in intactmore » rats and rats with area postrema lesions, it was shown that both groups of rats acquired taste aversions following injection of amphetamine, although the rats with lesions showed a less severe aversion than the intact rats. The results are interpreted as indicating that amphetamine-induced taste aversion learning may involve area postrema-mediated mechanisms, particularly at the lower doses, but that an intact area postrema is not a necessary condition for the acquisition of an amphetamine-induced taste aversion.« less

Nonlinear effects in subthreshold virtual electrode polarization.

PubMed

Sambelashvili, Aleksandre T; Nikolski, Vladimir P; Efimov, Igor R

2003-06-01

Introduction of the virtual electrode polarization (VEP) theory suggested solutions to several century-old puzzles of heart electrophysiology including explanation of the mechanisms of stimulation and defibrillation. Bidomain theory predicts that VEPs should exist at any stimulus strength. Although the presence of VEPs for strong suprathreshold pulses has been well documented, their existence at subthreshold strengths during diastole remains controversial. We studied cardiac membrane polarization produced by subthreshold stimuli in 1) rabbit ventricular muscle using high-resolution fluorescent imaging with the voltage-sensitive dye pyridinium 4-[2-[6-(dibutylamino)-2-naphthalenyl]-ethenyl]-1-(3-sulfopropyl)hydroxide (di-4-ANEPPS) and 2) an active bidomain model with Luo-Rudy ion channel kinetics. Both in vitro and in numero models show that the common dog-bone-shaped VEP is present at any stimulus strength during both systole and diastole. Diastolic subthreshold VEPs exhibited nonlinear properties that were expressed in time-dependent asymmetric reversal of membrane polarization with respect to stimulus polarity. The bidomain model reveals that this asymmetry is due to nonlinear properties of the inward rectifier potassium current. Our results suggest that active ion channel kinetics modulate the transmembrane polarization pattern that is predicted by the linear bidomain model of cardiac syncytium.

Hallucinogen Use Disorders Among Adult Users of MDMA and Other Hallucinogens

PubMed Central

Wu, Li-Tzy; Ringwalt, Christopher L.; Mannelli, Paolo; Patkar, Ashwin A.

2008-01-01

We investigated the prevalence, patterns, and correlates of past-year DSM-IV hallucinogen use disorders (HUDs) among past-year users of MDMA and other hallucinogens from a sample of Americans 18 or older (n = 37,227). Users were categorized as MDMA users and other hallucinogen users. Overall, one in five (20%) MDMA users and about one in six (16%) other hallucinogen users reported at least one clinical feature of HUDs. Among MDMA users, prevalence of hallucinogen abuse, subthreshold dependence, and dependence was 4.9%, 11.9%, and 3.6%, respectively. The majority with hallucinogen abuse displayed subthreshold dependence. Most with hallucinogen dependence exhibited abuse. Subthreshold hallucinogen dependence is relatively prevalent and represents a clinically important subgroup that warrants future research and consideration in a major diagnostic classification system. PMID:18770077

The Impact of the Shallow-Trench Isolation Effect on Flicker Noise of Source Follower MOSFETs in a CMOS Image Sensor.

PubMed

Fan, C C; Chiu, Y C; Liu, C; Lai, W W; Cheng, C H; Lin, D L; Li, G R; Lo, Y H; Chang, C W; Tsai, C C; Chang, C Y

2018-06-01

The flicker noise of source follower transistors is the dominant noise source in image sensors. This paper reports a systematic study of the shallow trench isolation effect in transistors with different sizes under high temperature conditions that correspond to the quantity of empty defect sites. The effects of shallow trench isolation sidewall defects on flicker noise characteristics are investigated. In addition, the low-frequency noise and subthreshold swing degrade simultaneously in accordance to the device gate width scaling. Both serious subthreshold leakage and considerable noise can be attributed to the high trap density near the STI edge. Consequently, we propose a coincidental relationship between the noise level and the subthreshold characteristic; its trend is identical to the experiments and simulation results.

GaN Nanowire MOSFET with Near-Ideal Subthreshold Slope.

PubMed

Li, Wenjun; Brubaker, Matt D; Spann, Bryan T; Bertness, Kris A; Fay, Patrick

2018-02-01

Wrap-around gate GaN nanowire MOSFETs using Al 2 O 3 as gate oxide have been experimentally demonstrated. The fabricated devices exhibit a minimum subthreshold slope of 60 mV/dec, an average subthreshold slope of 68 mV/dec over three decades of drain current, drain-induced barrier lowering of 27 mV/V, an on-current of 42 μA/μm (normalized by nanowire circumference), on/off ratio over 10 8 , an intrinsic transconductance of 27.8 μS/μm, for a switching efficiency figure of merit, Q=g m /SS of 0.41 μS/μm-dec/mV. These performance metrics make GaN nanowire MOSFETs a promising candidate for emerging low-power applications such as sensors and RF for the internet of things.

Efficient Defect Engineering for Solution Combustion Processed In-Zn-O thin films for high performance transistors

NASA Astrophysics Data System (ADS)

Liang, Xiaoci; Wang, Chengcai; Liang, Jun; Liu, Chuan; Pei, Yanli

2017-09-01

The oxygen related defects in the solution combustion-processed InZnO vitally affect the field-effect mobility and on-off characteristics in thin film transistors (TFTs). We use photoelectron spectroscopy to reveal that these defects can be well controlled by adjusting the atmosphere and flow rate during the combustion reaction, but are hardly affected by further post-annealing after the reaction. In device performance, the threshold voltage of the InZnO-TFTs was regulated in a wide range from 3.5 V to 11.0 V. To compromise the high field-effect mobility and good subthreshold properties, we fabricate the TFTs with double active layers of InZnO to achieve vertical gradience in defect distribution. The resulting TFT exhibits much higher field-effect mobility as 17.5 cm2 · V-1 · s-1, a low reversed sub-threshold slope as 0.35 V/decade, and a high on-off ratio as 107. The presented understandings and methods on defect engineering are efficient in improving the device performance of TFTs made from the combustion reaction process.

Design and Analysis of a Neuromemristive Reservoir Computing Architecture for Biosignal Processing

PubMed Central

Kudithipudi, Dhireesha; Saleh, Qutaiba; Merkel, Cory; Thesing, James; Wysocki, Bryant

2016-01-01

Reservoir computing (RC) is gaining traction in several signal processing domains, owing to its non-linear stateful computation, spatiotemporal encoding, and reduced training complexity over recurrent neural networks (RNNs). Previous studies have shown the effectiveness of software-based RCs for a wide spectrum of applications. A parallel body of work indicates that realizing RNN architectures using custom integrated circuits and reconfigurable hardware platforms yields significant improvements in power and latency. In this research, we propose a neuromemristive RC architecture, with doubly twisted toroidal structure, that is validated for biosignal processing applications. We exploit the device mismatch to implement the random weight distributions within the reservoir and propose mixed-signal subthreshold circuits for energy efficiency. A comprehensive analysis is performed to compare the efficiency of the neuromemristive RC architecture in both digital(reconfigurable) and subthreshold mixed-signal realizations. Both Electroencephalogram (EEG) and Electromyogram (EMG) biosignal benchmarks are used for validating the RC designs. The proposed RC architecture demonstrated an accuracy of 90 and 84% for epileptic seizure detection and EMG prosthetic finger control, respectively. PMID:26869876

Exploiting Sub-threshold and above-threshold characteristics in a silver-enhanced gold nanoparticle based biochip.

PubMed

Liu, Yang; Alocilja, Evangelyn; Chakrabartty, Shantanu

2009-01-01

Silver-enhanced labeling is a technique used in immunochromatographic assays for improving the sensitivity of pathogen detection. In this paper, we employ the silver enhancement approach for constructing a biomolecular transistor that uses a high-density interdigitated electrode to detect rabbit IgG. We show that the response of the biomolecular transistor comprises of: (a) a sub-threshold region where the conductance change is an exponential function of the enhancement time and; (b) an above-threshold region where the conductance change is a linear function with respect to the enhancement time. By exploiting both these regions of operation, it is shown that the silver enhancing time is a reliable indicator of the IgG concentration. The method provides a relatively straightforward alternative to biomolecular signal amplification techniques. The measured results using a biochip prototype fabricated in silicon show that 240 pg/mL rabbit IgG can be detected at the silver enhancing time of 42 min. Also, the biomolecular transistor is compatible with silicon based processing making it ideal for designing integrated CMOS biosensors.

Social Change and Increasing of Bipolar Disorders: An Evolutionary Model

PubMed Central

Carta, Mauro Giovanni

2013-01-01

Introduction: The objective of this paper is to see if behaviours defined as pathological and maladjusted in certain contexts may produce adaptive effects in other contexts, especially if they occur in attenuated form. Interactions between environment and behaviour are studied from an evolutionary standpoint in an attempt to understand how new attitudes emerge in an evolving context. Methodology: Narrative review. Following an historical examination of how the description of depression in Western society has changed, we examine a series of studies performed in areas where great changes have taken place as well as research on emigration from Sardinia in the 1960s and 70s and immigration to Sardinia in the 1990s. Results and conclusions: If we postulate that mood disorders are on the increase and that the epidemic began in the 17th century with the "English malady", we must suppose that at least the "light" forms have an adaptive advantage, otherwise the expansion of the disorder would have been self-limiting. "Compulsive hyper-responsabilization”, as well as explorative behaviours, may represent a base for adaptation in certain conditions of social change. The social emphasis in individualism and responsibility may have changed not only the frequency, but also the phenomenology of mood disorders particularly the increases in bipolar disorders. From the sociobiological standpoint the conditions that may favour "subthreshold" bipolar or depressive features are to be considered in relation to the contextual role of gender and the different risks of the two disorders in males and females. PMID:23878615

Social change and increasing of bipolar disorders: an evolutionary model.

PubMed

Carta, Mauro Giovanni

2013-01-01

The objective of this paper is to see if behaviours defined as pathological and maladjusted in certain contexts may produce adaptive effects in other contexts, especially if they occur in attenuated form. Interactions between environment and behaviour are studied from an evolutionary standpoint in an attempt to understand how new attitudes emerge in an evolving context. Narrative review. Following an historical examination of how the description of depression in Western society has changed, we examine a series of studies performed in areas where great changes have taken place as well as research on emigration from Sardinia in the 1960s and 70s and immigration to Sardinia in the 1990s. If we postulate that mood disorders are on the increase and that the epidemic began in the 17th century with the "English malady", we must suppose that at least the "light" forms have an adaptive advantage, otherwise the expansion of the disorder would have been self-limiting. "Compulsive hyper-responsabilization", as well as explorative behaviours, may represent a base for adaptation in certain conditions of social change. The social emphasis in individualism and responsibility may have changed not only the frequency, but also the phenomenology of mood disorders particularly the increases in bipolar disorders. From the sociobiological standpoint the conditions that may favour "subthreshold" bipolar or depressive features are to be considered in relation to the contextual role of gender and the different risks of the two disorders in males and females.

Subthreshold depressions: clinical and polysomnographic validation of dysthymic, residual and masked forms.

PubMed

Akiskal, H S; Judd, L L; Gillin, J C; Lemmi, H

1997-08-01

We summarize clinical and polysomnographic findings in support of the existence of a broad and prevalent spectrum of less than syndromal or subthreshold depressive conditions that constitute subeffective disorders. Many of these conditions were previously subsumed under such rubrics as 'neurotic,' 'characterological,' and 'existential' depressions. Prospective follow-up studies of neurotic depressions (defined by a predominance of the psychological features of, in most instances, less than syndromal depression) have demonstrated their transformation into moderate to melancholic or psychotic depressive, and even bipolar, disorders. Many characterological depressives (outpatients with early insidious onset and fluctuating chronicity of subthreshold manifestations falling short of full syndromal depression), were shown to have shortened REM latency, increased REM%, redistribution of REM to the first part of the night, classic diurnality, high rates of family history for mood disorders, positive response to antidepressants and sleep deprivation, and prospective follow-up course leading to major affective episodes. Shortened REM latency and related sleep neurophysiological disturbances have also been reported to characterize so-called 'borderline' personality disorder even when examined in the absence of concomitant major depression. Finally, among primary care referrals to a sleep disorders center, short REM latency was found in a large number of patients without subjective mood change but with somatic manifestations of depression (meeting Probable Feighner Depression and/or lesser subacute manifestations). Rather than being incidental, the REM disturbances in the foregoing studies appear consistently on consecutive nights of polysomnography in the subthreshold affective group; this was not the case for patients with non-affective personality and anxiety disorders. The findings overall tend to support a common neurophysiological substrate for subthreshold and melancholic depressions and, interpreted in the context of clinical observations, family history and follow-up course, uphold the validity of dysthymic, intermittent and subsyndromal depressions.

Re-establishment of Anxiety in Stress-Sensitized Mice Is Caused by Monocyte Trafficking from the Spleen to the Brain

PubMed Central

Wohleb, Eric S.; McKim, Daniel B.; Shea, Daniel T.; Powell, Nicole D.; Tarr, Andrew J.; Sheridan, John F.; Godbout, Jonathan P.

2014-01-01

Background Persistent anxiety-like symptoms may have an inflammatory-related pathophysiology. Our previous work using repeated social defeat (RSD) in mice showed that recruitment of peripheral myeloid cells to the brain is required for the development of anxiety. Here, we aimed to determine if 1) RSD promotes prolonged anxiety through redistribution of myeloid cells and 2) prior exposure to RSD sensitizes the neuroimmune axis to secondary subthreshold stress. Methods Mice were subjected to RSD and several immune and behavioral parameters were determined 0.5, 8, or 24 days later. In follow-up studies, control and RSD mice were subjected to subthreshold stress at 24 days. Results Repeated social defeat-induced macrophage recruitment to the brain corresponded with development and maintenance of anxiety-like behavior 8 days after RSD, but neither remained at 24 days. Nonetheless, social avoidance and an elevated neuroinflammatory profile were maintained at 24 days. Subthreshold social defeat in RSD-sensitized mice increased peripheral macrophage trafficking to the brain that promoted re-establishment of anxiety. Moreover, subthreshold social defeat increased social avoidance in RSD-sensitized mice compared with naïve mice. Stress-induced monocyte trafficking was linked to redistribution of myeloid progenitor cells in the spleen. Splenectomy before subthreshold stress attenuated macrophage recruitment to the brain and prevented anxiety-like behavior in RSD-sensitized mice. Conclusions These data indicate that monocyte trafficking from the spleen to the brain contributes re-establishment of anxiety in stress-sensitized mice. These findings show that neuroinflammatory mechanisms promote mood disturbances following stress-sensitization and outline novel neuroimmune interactions that underlie recurring anxiety disorders such as posttraumatic stress disorder. PMID:24439304

Re-establishment of anxiety in stress-sensitized mice is caused by monocyte trafficking from the spleen to the brain.

PubMed

Wohleb, Eric S; McKim, Daniel B; Shea, Daniel T; Powell, Nicole D; Tarr, Andrew J; Sheridan, John F; Godbout, Jonathan P

2014-06-15

Persistent anxiety-like symptoms may have an inflammatory-related pathophysiology. Our previous work using repeated social defeat (RSD) in mice showed that recruitment of peripheral myeloid cells to the brain is required for the development of anxiety. Here, we aimed to determine if 1) RSD promotes prolonged anxiety through redistribution of myeloid cells and 2) prior exposure to RSD sensitizes the neuroimmune axis to secondary subthreshold stress. Mice were subjected to RSD and several immune and behavioral parameters were determined .5, 8, or 24 days later. In follow-up studies, control and RSD mice were subjected to subthreshold stress at 24 days. Repeated social defeat-induced macrophage recruitment to the brain corresponded with development and maintenance of anxiety-like behavior 8 days after RSD, but neither remained at 24 days. Nonetheless, social avoidance and an elevated neuroinflammatory profile were maintained at 24 days. Subthreshold social defeat in RSD-sensitized mice increased peripheral macrophage trafficking to the brain that promoted re-establishment of anxiety. Moreover, subthreshold social defeat increased social avoidance in RSD-sensitized mice compared with naïve mice. Stress-induced monocyte trafficking was linked to redistribution of myeloid progenitor cells in the spleen. Splenectomy before subthreshold stress attenuated macrophage recruitment to the brain and prevented anxiety-like behavior in RSD-sensitized mice. These data indicate that monocyte trafficking from the spleen to the brain contributes re-establishment of anxiety in stress-sensitized mice. These findings show that neuroinflammatory mechanisms promote mood disturbances following stress-sensitization and outline novel neuroimmune interactions that underlie recurring anxiety disorders such as posttraumatic stress disorder. Copyright © 2014 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Classification models for subthreshold generalized anxiety disorder in a college population: Implications for prevention.

PubMed

Kanuri, Nitya; Taylor, C Barr; Cohen, Jeffrey M; Newman, Michelle G

2015-08-01

Generalized anxiety disorder (GAD) is one of the most common psychiatric disorders on college campuses and often goes unidentified and untreated. We propose a combined prevention and treatment model composed of evidence-based self-help (SH) and guided self-help (GSH) interventions to address this issue. To inform the development of this stepped-care model of intervention delivery, we evaluated results from a population-based anxiety screening of college students. A primary model was developed to illustrate how increasing levels of symptomatology could be linked to prevention/treatment interventions. We used screening data to propose four models of classification for populations at risk for GAD. We then explored the cost considerations of implementing this prevention/treatment stepped-care model. Among 2489 college students (mean age 19.1 years; 67% female), 8.0% (198/2489) met DSM-5 clinical criteria for GAD, in line with expected clinical rates for this population. At-risk Model 1 (subthreshold, but considerable symptoms of anxiety) identified 13.7% of students as potentially at risk for developing GAD. Model 2 (subthreshold, but high GAD symptom severity) identified 13.7%. Model 3 (subthreshold, but symptoms were distressing) identified 12.3%. Model 4 (subthreshold, but considerable worry) identified 17.4%. There was little overlap among these models, with a combined at-risk population of 39.4%. The efficiency of these models in identifying those truly at risk and the cost and efficacy of preventive interventions will determine if prevention is viable. Using Model 1 data and conservative cost estimates, we found that a preventive intervention effect size of even 0.2 could make a prevention/treatment model more cost-effective than existing models of "wait-and-treat." Copyright © 2015 Elsevier Ltd. All rights reserved.

Sub-threshold depolarizing pre-pulses can enhance the efficiency of biphasic stimuli in transcutaneous neuromuscular electrical stimulation.

PubMed

Vargas Luna, Jose Luis; Mayr, Winfried; Cortés-Ramirez, Jorge-Armando

2018-06-09

There is multiple evidence in the literature that a sub-threshold pre-pulse, delivered immediately prior to an electrical stimulation pulse, can alter the activation threshold of nerve fibers and motor unit recruitment characteristics. So far, previously published works combined monophasic stimuli with sub-threshold depolarizing pre-pulses (DPPs) with inconsistent findings-in some studies, the DPPs decreased the activation threshold, while in others it was increased. This work aimed to evaluate the effect of DPPs during biphasic transcutaneous electrical stimulation and to study the possible mechanism underlying those differences. Sub-threshold DPPs between 0.5 and 15 ms immediately followed by biphasic or monophasic pulses were administered to the tibial nerve; the electrophysiological muscular responses (motor-wave, M-wave) were monitored via electromyogram (EMG) recording from the soleus muscle. The data show that, under the specific studied conditions, DPPs tend to lower the threshold for nerve fiber activation rather than elevating it. DPPs with the same polarity as the leading phase of biphasic stimuli are more effective to increase the sensitivity. This work assesses for the first time the effect of DPPs on biphasic pulses, which are required to achieve charge-balanced stimulation, and it provides guidance on the effect of polarity and intensity to take full advantage of this feature. Graphical abstract In this work, the effect of sub-threshold depolarizing pre-pulses (DPP) is investigated in a setup with transcutaneous electrical stimulation. We found that, within the tested 0-15 ms DPP duration range, the DPPs administered immediately before biphasic pulses proportionally increase the nerve excitability as visible in the M-waves recorded from the soleus muscle. Interestingly, these findings oppose published results, where DPPs, administered immediately before monophasic stimuli via implanted electrodes, led to decrease of nerve excitability.

Subthreshold membrane potential oscillations in inferior olive neurons are dynamically regulated by P/Q- and T-type calcium channels: a study in mutant mice

PubMed Central

Choi, Soonwook; Yu, Eunah; Kim, Daesoo; Urbano, Francisco J; Makarenko, Vladimir; Shin, Hee-Sup; Llinás, Rodolfo R

2010-01-01

The role of P/Q- and T-type calcium channels in the rhythmic oscillatory behaviour of inferior olive (IO) neurons was investigated in mutant mice. Mice lacking either the CaV2.1 gene of the pore-forming α1A subunit for P/Q-type calcium channel, or the CaV3.1 gene of the pore-forming α1G subunit for T-type calcium channel were used. In vitro intracellular recording from IO neurons reveals that the amplitude and frequency of sinusoidal subthreshold oscillations (SSTOs) were reduced in the CaV2.1−/− mice. In the CaV3.1−/− mice, IO neurons also showed altered patterns of SSTOs and the probability of SSTO generation was significantly lower (15%, 5 of 34 neurons) than that of wild-type (78%, 31 of 40 neurons) or CaV2.1−/− mice (73%, 22 of 30 neurons). In addition, the low-threshold calcium spike and the sustained endogenous oscillation following rebound potentials were absent in IO neurons from CaV3.1−/− mice. Moreover, the phase-reset dynamics of oscillatory properties of single neurons and neuronal clusters in IO were remarkably altered in both CaV2.1−/− and CaV3.1−/− mice. These results suggest that both α1A P/Q- and α1G T-type calcium channels are required for the dynamic control of neuronal oscillations in the IO. These findings were supported by results from a mathematical IO neuronal model that incorporated T and P/Q channel kinetics. PMID:20547676

Travelling waves in a model of quasi-active dendrites with active spines

NASA Astrophysics Data System (ADS)

Timofeeva, Y.

2010-05-01

Dendrites, the major components of neurons, have many different types of branching structures and are involved in receiving and integrating thousands of synaptic inputs from other neurons. Dendritic spines with excitable channels can be present in large densities on the dendrites of many cells. The recently proposed Spike-Diffuse-Spike (SDS) model that is described by a system of point hot-spots (with an integrate-and-fire process) embedded throughout a passive tree has been shown to provide a reasonable caricature of a dendritic tree with supra-threshold dynamics. Interestingly, real dendrites equipped with voltage-gated ion channels can exhibit not only supra-threshold responses, but also sub-threshold dynamics. This sub-threshold resonant-like oscillatory behaviour has already been shown to be adequately described by a quasi-active membrane. In this paper we introduce a mathematical model of a branched dendritic tree based upon a generalisation of the SDS model where the active spines are assumed to be distributed along a quasi-active dendritic structure. We demonstrate how solitary and periodic travelling wave solutions can be constructed for both continuous and discrete spine distributions. In both cases the speed of such waves is calculated as a function of system parameters. We also illustrate that the model can be naturally generalised to an arbitrary branched dendritic geometry whilst remaining computationally simple. The spatio-temporal patterns of neuronal activity are shown to be significantly influenced by the properties of the quasi-active membrane. Active (sub- and supra-threshold) properties of dendrites are known to vary considerably among cell types and animal species, and this theoretical framework can be used in studying the combined role of complex dendritic morphologies and active conductances in rich neuronal dynamics.

Differential polarization of cortical pyramidal neuron dendrites through weak extracellular fields

PubMed Central

Obermayer, Klaus

2018-01-01

The rise of transcranial current stimulation (tCS) techniques have sparked an increasing interest in the effects of weak extracellular electric fields on neural activity. These fields modulate ongoing neural activity through polarization of the neuronal membrane. While the somatic polarization has been investigated experimentally, the frequency-dependent polarization of the dendritic trees in the presence of alternating (AC) fields has received little attention yet. Using a biophysically detailed model with experimentally constrained active conductances, we analyze the subthreshold response of cortical pyramidal cells to weak AC fields, as induced during tCS. We observe a strong frequency resonance around 10-20 Hz in the apical dendrites sensitivity to polarize in response to electric fields but not in the basal dendrites nor the soma. To disentangle the relative roles of the cell morphology and active and passive membrane properties in this resonance, we perform a thorough analysis using simplified models, e.g. a passive pyramidal neuron model, simple passive cables and reconstructed cell model with simplified ion channels. We attribute the origin of the resonance in the apical dendrites to (i) a locally increased sensitivity due to the morphology and to (ii) the high density of h-type channels. Our systematic study provides an improved understanding of the subthreshold response of cortical cells to weak electric fields and, importantly, allows for an improved design of tCS stimuli. PMID:29727454

Cross section calculations for subthreshold pion production in peripheral heavy-ion collisions

NASA Technical Reports Server (NTRS)

Norbury, J. W.; Cucinotta, F. A.; Deutchman, P. A.; Townsend, L. W.

1986-01-01

Total cross sections angular distributions, and spectral distributions for the exclusive production of charged and neutral subthreshold pions produced in peripheral nucleus-nucleus collisions are calculated by using a particle-hole formalism. The pions result from the formation and decay of an isobar giant resonance state formed in a C-12 nucleus. From considerations of angular momentum conservation and for the sake of providing a unique experimental signature, the other nucleus, chosen for this work to be C-12 also, is assumed to be excited to one of its isovector (1+) giant resonance states. The effects of nucleon recoil by the pion emission are included, and Pauli blocking and pion absorption effects are studied by varying the isobar width. Detailed comparisons with experimental subthreshold pion data for incident energies between 35 and 86 MeV/nucleon are made.

Tunnel field-effect transistor charge-trapping memory with steep subthreshold slope and large memory window

NASA Astrophysics Data System (ADS)

Kino, Hisashi; Fukushima, Takafumi; Tanaka, Tetsu

2018-04-01

Charge-trapping memory requires the increase of bit density per cell and a larger memory window for lower-power operation. A tunnel field-effect transistor (TFET) can achieve to increase the bit density per cell owing to its steep subthreshold slope. In addition, a TFET structure has an asymmetric structure, which is promising for achieving a larger memory window. A TFET with the N-type gate shows a higher electric field between the P-type source and the N-type gate edge than the conventional FET structure. This high electric field enables large amounts of charges to be injected into the charge storage layer. In this study, we fabricated silicon-oxide-nitride-oxide-semiconductor (SONOS) memory devices with the TFET structure and observed a steep subthreshold slope and a larger memory window.

The Effects of Subthreshold Priming Alerts on Pilots in the USAARL TH-67 Microsim

DTIC Science & Technology

2009-06-01

subthreshold priming, subliminal messaging, cockpit displays UNCLAS UNCLAS UNCLAS SAR 46 Loraine Parish St. Onge, PhD 334-255-6906 Reset...of subliminally alerting pilots of or preparing pilots for changing situations and trends without interrupting their primary cognitive task...results under certain priming durations. Three studies by Strahan, Spencer, and Zann (2002) suggest that subliminal priming can be used to enhance

The economic impact of subthreshold and clinical childhood mental disorders.

PubMed

Fatori, Daniel; Salum, Giovanni; Itria, Alexander; Pan, Pedro; Alvarenga, Pedro; Rohde, Luis Augusto; Bressan, Rodrigo; Gadelha, Ary; de Jesus Mari, Jair; Conceição do Rosário, Maria; Manfro, Gisele; Polanczyk, Guilherme; Miguel, Euripedes Constantino; Graeff-Martins, Ana Soledade

2018-04-28

Mental disorders are common health problems associated with serious impairment and economic impact. To estimate the costs of clinical and subthreshold mental disorders in a sample of Brazilian children. The High Risk Cohort Study is a community study conducted in two major Brazilian cities. Subjects were 6-14 years old children being registered at school. From an initial pool of 9937 children, two subgroups were further investigated using a random-selection (n = 958) and high-risk group selection procedure (n = 1554), resulting in a sample of 2512 subjects. Mental disorder assessment was made using the Development and Well-Being Assessment. Costs for each child were estimated from the following components: mental health and social services use, school problems and parental loss of productivity. Child subthreshold and clinical mental disorders showed lifetime mean total cost of $1750.9 and $3141.2, respectively. National lifetime cost estimate was $9.9 billion for subthreshold mental disorders and $11.6 billion for clinical mental disorders (values in US$ purchasing power parity). This study provides evidence that child mental disorders have a great economic impact on society. There is an urgent need to plan an effective system of care with cost-effective programs of treatment and prevention to reduce economic burden.

Psychophysiological Investigation of Combat Veterans with Subthreshold Post-traumatic Stress Disorder Symptoms.

PubMed

Costanzo, Michelle; Jovanovic, Tanja; Norrholm, Seth D; Ndiongue, Rochelle; Reinhardt, Brian; Roy, Michael J

2016-08-01

Military service members (SMs) with subthreshold combat-related post-traumatic stress disorder (PTSD) symptoms often have clinically significant functional impairment, even though they do not meet full PTSD criteria. We therefore assessed the psychophysical responses of SMs, upon their return from Afghanistan or Iraq, to a fear conditioning paradigm to better understand the biological underpinnings of symptom severity. Heart rate (HR), skin conductance, electromyography startle, and respiratory rate (RR) were monitored throughout three distinct phases of the paradigm-fear acquisition, fear inhibition, and fear extinction-while plasma catecholamines (epinephrine, norepinephrine, and dopamine) were measured at the end of fear inhibition. Those with higher PTSD symptom severity demonstrated elevations in HR and startle response to danger cues; elevated self-reported depression and anxiety; impaired functional status; poor skin conductance discrimination between danger and safety; and increases in HR and RR during fear extinction. Moreover, an inverse relationship was seen between plasma dopamine and HR during fear inhibition for those with high symptoms. Overall, the physiological responses we observed in our subthreshold PTSD population parallel what has been previously observed in full PTSD, making a case for addressing subthreshold PTSD symptoms in combat veterans. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Major Depressive Disorder with Sub-threshold Bipolarity in the National Comorbidity Survey Replication

PubMed Central

Angst, Jules; Cui, Lihong; Swendsen, J. Joel; Rothen, S.; Cravchik, Anibal; Kessler, Ronald; Merikangas, Kathleen

2011-01-01

Objectives There is growing clinical and epidemiologic evidence indicating that major mood disorders form a spectrum from Major Depressive Disorder (MDD) to pure mania. The present investigation examined the prevalence and clinical correlates of MDD with sub-threshold bipolarity vs. pure MDD in the National Comorbidity Survey Replication (NCS-R). Methods The NCS-R is a nationally representative face-to-face household survey of the U.S. population conducted between February, 2001 and April, 2003. Lifetime history of mood disorders, symptoms and clinical indicators of severity were collected using version 3.0 of the WHO Composite International Diagnostic Interview, a fully structured lay-administered diagnostic interview. Results Nearly 40% of study participants with a history of major depressive disorder had a history of sub-threshold hypomania. This subgroup had a younger age of disorder onset, more episodes of depression, and higher rates of comorbidity than those without a history of hypomania, and lower levels of clinical severity than those with bipolar II disorder. Conclusions The findings demonstrate heterogeneity of major depressive disorder and support the validity of inclusion of sub-threshold mania in the diagnostic classification. The broadening of criteria for bipolar disorder would have important implications for research and clinical practice. PMID:20713498

Kv1.1 channelopathy abolishes presynaptic spike width modulation by subthreshold somatic depolarization

PubMed Central

Vivekananda, Umesh; Novak, Pavel; Bello, Oscar D.; Korchev, Yuri E.; Krishnakumar, Shyam S.; Volynski, Kirill E.; Kullmann, Dimitri M.

2017-01-01

Although action potentials propagate along axons in an all-or-none manner, subthreshold membrane potential fluctuations at the soma affect neurotransmitter release from synaptic boutons. An important mechanism underlying analog–digital modulation is depolarization-mediated inactivation of presynaptic Kv1-family potassium channels, leading to action potential broadening and increased calcium influx. Previous studies have relied heavily on recordings from blebs formed after axon transection, which may exaggerate the passive propagation of somatic depolarization. We recorded instead from small boutons supplied by intact axons identified with scanning ion conductance microscopy in primary hippocampal cultures and asked how distinct potassium channels interact in determining the basal spike width and its modulation by subthreshold somatic depolarization. Pharmacological or genetic deletion of Kv1.1 broadened presynaptic spikes without preventing further prolongation by brief depolarizing somatic prepulses. A heterozygous mouse model of episodic ataxia type 1 harboring a dominant Kv1.1 mutation had a similar broadening effect on basal spike shape as deletion of Kv1.1; however, spike modulation by somatic prepulses was abolished. These results argue that the Kv1.1 subunit is not necessary for subthreshold modulation of spike width. However, a disease-associated mutant subunit prevents the interplay of analog and digital transmission, possibly by disrupting the normal stoichiometry of presynaptic potassium channels. PMID:28193892

Effects of an Internet-based cognitive behavioral therapy (iCBT) program in Manga format on improving subthreshold depressive symptoms among healthy workers: a randomized controlled trial.

PubMed

Imamura, Kotaro; Kawakami, Norito; Furukawa, Toshi A; Matsuyama, Yutaka; Shimazu, Akihito; Umanodan, Rino; Kawakami, Sonoko; Kasai, Kiyoto

2014-01-01

The purpose of this study was to develop a new Internet-based computerized cognitive behavior therapy (iCBT) program in Manga format, the Japanese cartoon, for workers and to examine the effects of the iCBT program on improving subthreshold depression using a randomized controlled trial (RCT) design among workers employed in private companies in Japan. All workers in a company (n = 290) and all workers in three departments (n = 1,500) at the headquarters of another large company were recruited by an invitation e-mail. Participants who fulfilled the inclusion criteria were randomly allocated to intervention or control groups (N = 381 for each group). A six-week, six-lesson iCBT program using Manga (Japanese comic) story was developed. The program included several CBT skills: self-monitoring, cognitive restructuring, assertiveness, problem solving, and relaxation. The intervention group studied the iCBT program at a frequency of one lesson per week. Depression (Beck Depression Inventory II; BDI-II) was assessed as a primary outcome at baseline, and three- and six-month follow-ups for both intervention and control groups were performed. The iCBT program showed a significant intervention effect on BDI-II (t = -1.99, p<0.05) with small effect sizes (Cohen's d: -0.16, 95% Confidence Interval: -0.32 to 0.00, at six-month follow-up). The present study first demonstrated that a computerized cognitive behavior therapy delivered via the Internet was effective in improving depression in the general working population. It seems critical to improve program involvement of participants in order to enhance the effect size of an iCBT program. UMIN Clinical Trials Registry UMIN000006210.

Bullying behaviour in schools, socioeconomic position and psychiatric morbidity: a cross-sectional study in late adolescents in Greece

PubMed Central

2012-01-01

Background Bullying is quite prevalent in the school setting and has been associated with the socioeconomic position and psychiatric morbidity of the pupils. The aim of the study was to investigate the association between bullying and socioeconomic status in a sample of Greek adolescents and to examine whether this is confounded by the presence of psychiatric morbidity, including sub-threshold forms of illness. Methods 5,614 adolescents aged 16-18 years old and attending 25 senior high schools were screened and a stratified random sample of 2,427 were selected for a detailed interview. Psychiatric morbidity was assessed with a fully structured psychiatric interview, the revised Clinical Interview Schedule (CIS-R), while bullying was assessed with the revised Olweus bully/victim questionnaire. The following socio-economic variables were assessed: parental educational level and employment status, financial difficulties of the family and adolescents' school performance. The associations were investigated using multinomial logit models. Results 26.4% of the pupils were involved in bullying-related behaviours at least once monthly either as victims, perpetrators or both, while more frequent involvement (at least once weekly) was reported by 4.1%. Psychiatric morbidity was associated with all types of bullying-related behaviours. No socioeconomic associations were reported for victimization. A lower school performance and unemployment of the father were significantly more likely among perpetrators, while economic inactivity of the mother was more likely in pupils who were both victims and perpetrators. These results were largely confirmed when we focused on high frequency behaviours only. In addition, being overweight increased the risk of frequent victimization. Conclusions The prevalence of bullying among Greek pupils is substantial. Perpetration was associated with some dimensions of adolescents' socioeconomic status, while victimization showed no socioeconomic associations. Our findings may add to the understanding of possible risk factors for bullying behaviours in adolescence. PMID:22325708

Determination of 20Ne(p ,γ )21Na cross sections from Ep=500 -2000 keV

NASA Astrophysics Data System (ADS)

Lyons, S.; Görres, J.; deBoer, R. J.; Stech, E.; Chen, Y.; Gilardy, G.; Liu, Q.; Long, A. M.; Moran, M.; Robertson, D.; Seymour, C.; Vande Kolk, B.; Wiescher, M.; Best, A.

2018-06-01

Background: The reaction 20Ne(p ,γ )21Na influences the nucleosynthesis of Ne, Na, and Mg isotopes while contributing to hydrogen burning in several stellar sites, such as red giants, asymptotic giant branch (AGB) stars, massive stars, and oxygen-neon (ONe) novae. In the relevant temperature range for these environments (T = 0.05-0.5 GK), the main contributions to this reaction rate are from the direct capture process as well as the high-energy tail of a subthreshold resonance in the ground-state transition at Ex = 2425 keV in the 21Na compound nucleus. Purpose: The previous measurement of this reaction reports cross sections with large uncertainties for the ground-state transition. At higher energies, where the subthreshold resonance makes a smaller contribution to the total cross section, only upper limits are provided. This work aims to reduce the uncertainty in the cross section where direct capture dominates, as well as provide cross-section data in previously unmeasured regions. Method: The 20Ne(p ,γ )21Na reaction was measured over a wide proton energy range (Ep = 0.5-2.0 MeV) at θlab = 90∘. Transitions to the ground state and to the 332 and 2425 keV excited states were observed. The primary transitions to these three bound states were utilized in an R -matrix analysis to determine the contributions of the direct capture and the subthreshold resonance to the total cross section. Results: The cross sections of the present measurements have been found to be in good agreement with the previous data at low energy. Significantly improved cross-section measurements have been obtained over the Ep = 1300-1900 keV region. The narrow resonance at Ec.m. = 1113 keV (Ex = 3544.3 keV) has also been remeasured and its strength has been found to be in good agreement with previous measurements. Conclusions: An extrapolation of the S factor of 20Ne(p ,γ )21Na has been made to low energies using the R -matrix fit. The reaction rate from the subthreshold resonance was found to be the main contributor to the reaction rate at temperatures below about 0.1 GK. The present rate is lower in the temperature range of interest than those presented in current reaction rate libraries by up to 20%.

Fabrication and Benchmarking of a Stratix V FPGA with Monolithic Integrated Microfluidic Cooling

DTIC Science & Technology

2017-03-01

run. The output from all cores were monitored through the Altera Signaltap tool in order to detect glitches which occurred in the output...dependence on temperature, and static/ leakage power, which comes from several components, such as subthreshold leakage , gate leakage , and reverse bias 220...junction current. Subthreshold leakage current tends to be the most significant temperature dependent component of the power [6,7] and is given by

Back bias induced dynamic and steep subthreshold swing in junctionless transistors

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

Parihar, Mukta Singh; Kranti, Abhinav, E-mail: akranti@iiti.ac.in

In this work, we analyze back bias induced steep and dynamic subthreshold swing in junctionless double gate transistors operated in the asymmetric mode. This impact ionization induced dynamic subthreshold swing is explained in terms of the ratio between minimum hole concentration and peak electron concentration, and the dynamic change in the location of the conduction channel with applied front gate voltage. The reason for the occurrence of impact ionization at sub-bandgap drain voltages in silicon junctionless transistors is also accounted for. The optimum junctionless transistor operating at a back gate bias of −0.9 V, achieves over 5 orders of change inmore » drain current at a gate overdrive of 200 mV and drain bias of 1 V. These results for junctionless transistors are significantly better than those exhibited by silicon tunnel field effect transistors operating at the same drain bias.« less

Channel layer thickness dependence of In-Ti-Zn-O thin-film transistors fabricated using pulsed laser deposition

NASA Astrophysics Data System (ADS)

Zhang, Q.; Shan, F. K.; Liu, G. X.; Liu, A.; Lee, W. J.; Shin, B. C.

2014-05-01

Amorphous indium-titanium-zinc-oxide (ITZO) thin-film transistors (TFTs) with various channel thicknesses were fabricated at room temperature by using pulsed laser deposition. The channel layer thickness (CLT) dependence of the TFTs was investigated. All the ITZO thin films were amorphous, and the surface roughnesses decreased slightly first and then increased with increasing CLT. With increasing CLT from 35 to 140 nm, the on/off current ratio and the field-effect mobility increased, and the subthreshold swing decreased. The TFT with a CLT of 210 nm exhibited the worst performance, while the ITZO TFT with a CLT of 140 nm exhibited the best performance with a subthreshold voltage of 2.86 V, a mobility of 53.9 cm2V-1s-1, a subthreshold swing of 0.29 V/decade and an on/off current ratio of 109.

Who is MADD? Mixed anxiety depressive disorder in the general population.

PubMed

Spijker, Jan; Batelaan, Neeltje; de Graaf, Ron; Cuijpers, Pim

2010-02-01

Diagnostic criteria for (subthreshold) mixed anxiety depression (MADD) were proposed in DSM-IV. Yet the usefulness of this classification is questioned. We therefore assessed the prevalence of MADD, and investigated whether MADD adds to separate classifications of pure subthreshold depression and anxiety. Data of the Netherlands Mental Health and Incidence Study were used. The 12-month prevalence of MADD was 0.6%. Between the three subthreshold categories few differences were found with regard to socio-demographic variables, care utilisation and functioning. Course in MADD seems more favourable and MADD is not a stable diagnosis over time. The MADD criteria used in the present study differed slightly from the proposed criteria in DSM-IV and sample sizes were small. Given these results, MADD is not a relevant diagnosis in terms of prevalence and consequences when classified according to the currently proposed criteria. 2009 Elsevier B.V. All rights reserved.

Predictors of drusen reduction after subthreshold infrared (810 nm) diode laser macular grid photocoagulation for nonexudative age-related macular degeneration.

PubMed

Rodanant, Nuttawut; Friberg, Thomas R; Cheng, Lingyun; Aurora, Ajay; Bartsch, Dirk; Toyoguchi, Mitsuko; Corbin, Patricia S; El-Bradey, Mohamed H; Freeman, William R

2002-10-01

To determine the predictors of drusen reduction in eyes with nonexudative age-related macular degeneration (ARMD) treated with subthreshold infrared (810 nm) diode laser macular grid photocoagulation. Additionally, to determine the relationship of laser-induced drusen reduction and best-corrected visual acuity (BCVA) 18 months after laser treatment. Randomized controlled clinical trial. Fifty patients (100 eyes) with bilateral nonexudative ARMD were enrolled at two centers. One eye of each patient was randomized to the observation; the other eye was treated with 48 subthreshold (invisible end point) applications of infrared (810 nm) diode laser in a macular grid pattern. The eyes that received subthreshold laser treatment were compared with the eyes that received no treatment. The baseline fundus characteristics (number, size, and distribution of drusen, as well as focal hyperpigmentation) from two macula areas (central 1500 micro diameter, pericentral 1500 micro ring area) on stereo color photographs, the number of laser-induced lesions, and the area of laser induced retinal pigment epithelial (RPE) lesions on fluorescein angiography 3 months after treatment were studied as predictors of major drusen reduction (> or = 50% drusen reduction from baseline) 18 months after laser treatment. BCVA at baseline and 18 months later was compared in observation eyes and in laser-treated eyes. Eighteen months after randomization, 24 (48%) of 50 eyes treated with subthreshold laser had major drusen reduction compared with three (6%) of 50 observation eyes (P =.00001). At 3 months post-treatment in laser-treated eyes with major drusen reduction, the mean number of laser-induced lesions on fluorescein angiography was 30.7 and the mean area of RPE change was 0.81 mm(2) compared with 14.8 laser-induced lesions and 0.35 mm(2) area of RPE change in eyes without major drusen reduction (P =.0001 and P =.0003, respectively). At baseline, fundus characteristics were not significantly different between observation eyes and laser-treated eyes or between the major drusen reduction group and the nonmajor drusen reduction group. At 18 months after treatment, BCVA was not significantly different in laser-treated eyes and in observation eyes. Subthreshold infrared (810 nm) diode laser macular grid photocoagulation in eyes with nonexudative ARMD significantly reduced drusen 18 months after laser treatment. Both the number of subthreshold laser lesions and the area of RPE changes visible on fluorescein angiography 3 months after treatment appeared to be predictors for major drusen reduction 18 months after treatment. However, it remains to be determined whether laser-induced drusen reduction is beneficial for visual acuity or reduces the incidence of choroidal neovascularization (CNV) in eyes with nonexudative ARMD.

Subthreshold transpupillary thermotherapy reduces experimental choroidal neovascularization in the mouse without collateral damage to the neural retina.

PubMed

Ming, Yue; Algvere, Peep V; Odergren, Anne; Berglin, Lennart; van der Ploeg, Ingeborg; Seregard, Stefan; Kvanta, Anders

2004-06-01

Transpupillary thermotherapy (TTT) is currently being evaluated for treatment of choroidal neovascularization (CNV) in age-related macular degeneration. To optimize TTT for CNV, the effect was analyzed of invisible (subthreshold) or visible (threshold) doses of TTT on the normal mouse retina and on experimental CNV. TTT was delivered to the normal retina of 42 mice with a diode laser at increasing power settings (50, 60, 70, or 80 mW), to obtain thermal lesions ranging from invisible (subthreshold) to visible (threshold) burns. CNV was induced in 53 mice by krypton laser photocoagulation of the fundus, after which the CNV lesions were treated with TTT (50, 60, or 80 mW). Eyes were enucleated 7 days after TTT and prepared for histology, and the CNV complex was evaluated on hematoxylin-eosin stained serial sections by measuring the maximum height of the CNV lesions. Ultrastructural changes were examined by transmission electron microscopy. Increasing the TTT laser power yielded gradually more visible effects. At 50 mW, which induced subthreshold burns, no damage was seen in the neural retina, retinal pigment epithelium (RPE), or choroid at any time point. By contrast, eyes treated with higher power exhibited progressively more damage to the neural retina, including a complete disruption of the outer nuclear layer. When TTT was applied to the laser-induced CNV lesions, the height of lesions was significantly reduced (P < 0.001) in response to all three power settings at 7 days after treatment. The mean relative thickness of the CNV lesion was 3.29 +/- 0.89 in untreated mice, whereas in TTT-treated mice it was 1.69 +/- 0.35, 1.69 +/- 0.41 and 1.70 +/- 0.17 at power settings of 50, 60, and 80 mW, respectively. The overlying neural retina showed no apparent damage with the 50- or 60-mW settings, whereas outer nuclear layer disruption occurred with a power of 80 mW. Electron microscopy confirmed the presence of vascular occlusion at 1 day and a fibrotic scar at 7 days after TTT. Subthreshold TTT can effectively occlude newly formed vessels and cause regression of the experimental CNV complex without damaging the neural retina. The results demonstrate the importance of using subthreshold laser power in experimental and clinical evaluation of TTT.

Scaling of Device Variability and Subthreshold Swing in Ballistic Carbon Nanotube Transistors

NASA Astrophysics Data System (ADS)

Cao, Qing; Tersoff, Jerry; Han, Shu-Jen; Penumatcha, Ashish V.

2015-08-01

In field-effect transistors, the inherent randomness of dopants and other charges is a major cause of device-to-device variability. For a quasi-one-dimensional device such as carbon nanotube transistors, even a single charge can drastically change the performance, making this a critical issue for their adoption as a practical technology. Here we calculate the effect of the random charges at the gate-oxide surface in ballistic carbon nanotube transistors, finding good agreement with the variability statistics in recent experiments. A combination of experimental and simulation results further reveals that these random charges are also a major factor limiting the subthreshold swing for nanotube transistors fabricated on thin gate dielectrics. We then establish that the scaling of the nanotube device uniformity with the gate dielectric, fixed-charge density, and device dimension is qualitatively different from conventional silicon transistors, reflecting the very different device physics of a ballistic transistor with a quasi-one-dimensional channel. The combination of gate-oxide scaling and improved control of fixed-charge density should provide the uniformity needed for large-scale integration of such novel one-dimensional transistors even at extremely scaled device dimensions.

Impact of negative capacitance effect on Germanium Double Gate pFET for enhanced immunity to interface trap charges

NASA Astrophysics Data System (ADS)

Bansal, Monika; Kaur, Harsupreet

2018-05-01

In this work, a comprehensive drain current model has been developed for long channel Negative Capacitance Germanium Double Gate p-type Field Effect Transistor (NCGe-DG-pFET) by using 1-D Poisson's equation and Landau-Khalatnikov equation. The model takes into account interface trap charges and by using the derived model various parameters such as surface potential, gain, gate capacitance, subthreshold swing, drain current, transconductance, output conductance and Ion/Ioff ratio have been obtained and it is demonstrated that by incorporating ferroelectric material as gate insulator with Ge-channel, subthreshold swing values less than 60 mV/dec can be achieved along with improved gate controllability and current drivability. Further, to critically analyze the advantages offered by NCGe-DG-pFET, a detailed comparison has been done with Germanium Double Gate p-type Field Effect Transistor (Ge-DG-pFET) and it is shown that NCGe-DG-pFET exhibits high gain, enhanced transport efficiency in channel, very less or negligible degradation in device characteristics due to interface trap charges as compared to Ge-DG-pFET. The analytical results so obtained show good agreement with simulated results obtained from Silvaco ATLAS TCAD tool.

Josephson-CMOS Hybrid Memories

DTIC Science & Technology

2007-04-25

threshold voltage. The subthreshold behavior is critical for dynamic circuits since it determines the static power and retention time of a dynamic memory...results of subthreshold behaviors for different temperatures are shown in Fig. 2.9, the simulated results con- firm the analysis above. Also, experimental...0.5-26.5 GHz 25 dB gain), but they are not on-chip because they comsume so much power (9 W) that you cannot afford to build them on chip. [52] Another

Extreme sub-threshold swing in tunnelling relays

NASA Astrophysics Data System (ADS)

AbdelGhany, M.; Szkopek, T.

2014-01-01

We propose and analyze the theory of the tunnelling relay, a nanoscale active device in which tunnelling current is modulated by electromechanical actuation of a suspended membrane above a fixed electrode. The tunnelling current is modulated exponentially with vacuum gap length, permitting an extreme sub-threshold swing of ˜10 mV/decade breaking the thermionic limit. The predicted performance suggests that a significant reduction in dynamic energy consumption over conventional field effect transistors is physically achievable.

Significant long-term reduction in n-channel MESFET subthreshold leakage using ammonium-sulfide surface treated gates

NASA Technical Reports Server (NTRS)

Neudeck, P. G.; Carpenter, M. S.; Melloch, Michael R.; Cooper, James A., Jr.

1991-01-01

Ammonium-sulfide (NH4)2S treated gates have been employed in the fabrication of GaAs MESFETs that exhibit a remarkable reduction in subthreshold leakage current. A greater than 100-fold reduction in drain current minimum is observed due to a decrease in Schottky gate leakage. The electrical characteristics have remained stable for over a year during undesiccated storage at room temperature, despite the absence of passivation layers.

Indirect study of 12C(α,γ)16O reaction

NASA Astrophysics Data System (ADS)

Hammache, F.; Oulebsir, N.; Roussel, P.; Pellegriti, M. G.; Audouin, L.; Beaumel, D.; Bouda, A.; Descouvemont, P.; Fortier, S.; Gaudefroy, L.; Kiener, J.; Lefebvre-Schuhl, A.; Tatischeff, V.

2016-01-01

The radiative capture reaction 12C(α,γ)16O plays an important role in helium burning in massive stars and their subsequent evolution [1]. However, despite various experimental studies, the cross section of this reaction at stellar energies remains highly uncertain. The extrapolation down to stellar energy (Ecm˜300 keV) of the measured cross sections at higher energies is made difficult by the overlap of various contributions of which some are badly known such as that of the 2+ (Ex=6.92 MeV) and 1- (Ex=7.12 MeV) sub-threshold states of 16O. Hence, to further investigate the contribution of these two-subthreshold resonances to the 12C(α,γ)16O cross section, a new determination of their a-reduced widths and so their a- spectroscopic-factors was performed using 12C(7Li,t)16O transfer reaction measurements at two incident energies and a detailed DWBA analysis of the data [2]. The measured and calculated differential cross sections are presented as well as the obtained spectroscopic factors and the a- reduced widths as well as the assymptotic normalization constants (ANC) for the 2+ and 1- subthreshold states. Finally, the results obtained from the R-matrix calculations of the 12C(α,γ)16O cross section using our obtained a-reduced widths for the two sub-threshold resonances are presented and discussed.

Contrast-enhanced ultrasound evaluation of pancreatic cancer xenografts in nude mice after irradiation with sub-threshold focused ultrasound for tumor ablation

PubMed Central

Wang, Rui; Guo, Qian; Chen, Yi Ni; Hu, Bing; Jiang, Li Xin

2017-01-01

We evaluated the efficacy of contrast-enhanced ultrasound for assessing tumors after irradiation with sub-threshold focused ultrasound (FUS) ablation in pancreatic cancer xenografts in nude mice. Thirty tumor-bearing nude mice were divided into three groups: Group A received sham irradiation, Group B received a moderate-acoustic energy dose (sub-threshold), and Group C received a high-acoustic energy dose. In Group B, B-mode ultrasound (US), color Doppler US, and dynamic contrast-enhanced ultrasound (DCE-US) studies were conducted before and after irradiation. After irradiation, tumor growth was inhibited in Group B, and the tumors shrank in Group C. In Group A, the tumor sizes were unchanged. In Group B, contrast-enhanced ultrasound (CEUS) images showed a rapid rush of contrast agent into and out of tumors before irradiation. After irradiation, CEUS revealed contrast agent perfusion only at the tumor periphery and irregular, un-perfused volumes of contrast agent within the tumors. DCE-US perfusion parameters, including peak intensity (PI) and area under the curve (AUC), had decreased 24 hours after irradiation. PI and AUC were increased 48 hours and 2weeks after irradiation. Time to peak (TP) and sharpness were increased 24 hours after irradiation. TP decreased at 48 hours and 2 weeks after irradiation. CEUS is thus an effective method for early evaluation after irradiation with sub-threshold FUS. PMID:28402267

Telephone cognitive-behavioral therapy for subthreshold depression and presenteeism in workplace: a randomized controlled trial.

PubMed

Furukawa, Toshi A; Horikoshi, Masaru; Kawakami, Norito; Kadota, Masayo; Sasaki, Megumi; Sekiya, Yuki; Hosogoshi, Hiroki; Kashimura, Masami; Asano, Kenichi; Terashima, Hitomi; Iwasa, Kazunori; Nagasaku, Minoru; Grothaus, Louis C

2012-01-01

Subthreshold depression is highly prevalent in the general population and causes great loss to society especially in the form of reduced productivity while at work (presenteeism). We developed a highly-structured manualized eight-session cognitive-behavioral program with a focus on subthreshold depression in the workplace and to be administered via telephone by trained psychotherapists (tCBT). We conducted a parallel-group, non-blinded randomized controlled trial of tCBT in addition to the pre-existing Employee Assistance Program (EAP) versus EAP alone among workers with subthreshold depression at a large manufacturing company in Japan. The primary outcomes were depression severity as measured with Beck Depression Inventory-II (BDI-II) and presenteeism as measured with World Health Organization Health and Work Productivity Questionnaire (HPQ). In the course of the trial the follow-up period was shortened in order to increase acceptability of the study. The planned sample size was 108 per arm but the trial was stopped early due to low accrual. Altogether 118 subjects were randomized to tCBT+EAP (n = 58) and to EAP alone (n = 60). The BDI-II scores fell from the mean of 17.3 at baseline to 11.0 in the intervention group and to 15.7 in the control group after 4 months (p<0.001, Effect size = 0.69, 95%CI: 0.32 to 1.05). However, there was no statistically significant decrease in absolute and relative presenteeism (p = 0.44, ES = 0.15, -0.21 to 0.52, and p = 0.50, ES = 0.02, -0.34 to 0.39, respectively). Remote CBT, including tCBT, may provide easy access to quality-assured effective psychotherapy for people in the work force who present with subthreshold depression. Further studies are needed to evaluate the effectiveness of this approach in longer terms. The study was funded by Sekisui Chemicals Co. Ltd. ClinicalTrials.gov NCT00885014.

Electrical characteristics and density of states of thin-film transistors based on sol-gel derived ZnO channel layers with different annealing temperatures

NASA Astrophysics Data System (ADS)

Wang, S.; Mirkhani, V.; Yapabandara, K.; Cheng, R.; Hernandez, G.; Khanal, M. P.; Sultan, M. S.; Uprety, S.; Shen, L.; Zou, S.; Xu, P.; Ellis, C. D.; Sellers, J. A.; Hamilton, M. C.; Niu, G.; Sk, M. H.; Park, M.

2018-04-01

We report on the fabrication and electrical characterization of bottom gate thin-film transistors (TFTs) based on a sol-gel derived ZnO channel layer. The effect of annealing of ZnO active channel layers on the electrical characteristics of the ZnO TFTs was systematically investigated. Photoluminescence (PL) spectra indicate that the crystal quality of the ZnO improves with increasing annealing temperature. Both the device turn-on voltage (Von) and threshold voltage (VT) shift to a positive voltage with increasing annealing temperature. As the annealing temperature is increased, both the subthreshold slope and the interfacial defect density (Dit) decrease. The field effect mobility (μFET) increases with annealing temperature, peaking at 800 °C and decreases upon further temperature increase. An improvement in transfer and output characteristics was observed with increasing annealing temperature. However, when the annealing temperature reaches 900 °C, the TFTs demonstrate a large degradation in both transfer and output characteristics, which is possibly produced by non-continuous coverage of the film. By using the temperature-dependent field effect measurements, the localized sub-gap density of states (DOSs) for ZnO TFTs with different annealing temperatures were determined. The DOSs for the subthreshold regime decrease with increasing annealing temperature from 600 °C to 800 °C and no substantial change was observed with further temperature increase to 900 °C.

Performance Evaluation and Improvement of Ferroelectric Field-Effect Transistor Memory

NASA Astrophysics Data System (ADS)

Yu, Hyung Suk

Flash memory is reaching scaling limitations rapidly due to reduction of charge in floating gates, charge leakage and capacitive coupling between cells which cause threshold voltage fluctuations, short retention times, and interference. Many new memory technologies are being considered as alternatives to flash memory in an effort to overcome these limitations. Ferroelectric Field-Effect Transistor (FeFET) is one of the main emerging candidates because of its structural similarity to conventional FETs and fast switching speed. Nevertheless, the performance of FeFETs have not been systematically compared and analyzed against other competing technologies. In this work, we first benchmark the intrinsic performance of FeFETs and other memories by simulations in order to identify the strengths and weaknesses of FeFETs. To simulate realistic memory applications, we compare memories on an array structure. For the comparisons, we construct an accurate delay model and verify it by benchmarking against exact HSPICE simulations. Second, we propose an accurate model for FeFET memory window since the existing model has limitations. The existing model assumes symmetric operation voltages but it is not valid for the practical asymmetric operation voltages. In this modeling, we consider practical operation voltages and device dimensions. Also, we investigate realistic changes of memory window over time and retention time of FeFETs. Last, to improve memory window and subthreshold swing, we suggest nonplanar junctionless structures for FeFETs. Using the suggested structures, we study the dimensional dependences of crucial parameters like memory window and subthreshold swing and also analyze key interference mechanisms.

Stochastic resonance enhancement of small-world neural networks by hybrid synapses and time delay

NASA Astrophysics Data System (ADS)

Yu, Haitao; Guo, Xinmeng; Wang, Jiang

2017-01-01

The synergistic effect of hybrid electrical-chemical synapses and information transmission delay on the stochastic response behavior in small-world neuronal networks is investigated. Numerical results show that, the stochastic response behavior can be regulated by moderate noise intensity to track the rhythm of subthreshold pacemaker, indicating the occurrence of stochastic resonance (SR) in the considered neural system. Inheriting the characteristics of two types of synapses-electrical and chemical ones, neural networks with hybrid electrical-chemical synapses are of great improvement in neuron communication. Particularly, chemical synapses are conducive to increase the network detectability by lowering the resonance noise intensity, while the information is better transmitted through the networks via electrical coupling. Moreover, time delay is able to enhance or destroy the periodic stochastic response behavior intermittently. In the time-delayed small-world neuronal networks, the introduction of electrical synapses can significantly improve the signal detection capability by widening the range of optimal noise intensity for the subthreshold signal, and the efficiency of SR is largely amplified in the case of pure chemical couplings. In addition, the stochastic response behavior is also profoundly influenced by the network topology. Increasing the rewiring probability in pure chemically coupled networks can always enhance the effect of SR, which is slightly influenced by information transmission delay. On the other hand, the capacity of information communication is robust to the network topology within the time-delayed neuronal systems including electrical couplings.

InN/InGaN complementary heterojunction-enhanced tunneling field-effect transistor with enhanced subthreshold swing and tunneling current

NASA Astrophysics Data System (ADS)

Peng, Yue; Han, Genquan; Wang, Hongjuan; Zhang, Chunfu; Liu, Yan; Wang, Yibo; Zhao, Shenglei; Zhang, Jincheng; Hao, Yue

2016-05-01

InN/In0.75Ga0.25N complementary heterojunction-enhanced tunneling field-effect transistors (HE-TFETs) were characterized using the numerical simulation. InN/In0.75Ga0.25N HE-TFET has an InN/In0.75Ga0.25N heterojunction located in the channel region with a distance of LT-H from the source/channel tunneling junction. We demonstrate that, for both n- and p-channel devices, HE-TFETs have a delay of onset voltage VONSET, a steeper subthreshold swing (SS), and an enhanced on-state current ION in comparison with the homo-TFETs. InN/In0.75Ga0.25N n- and p-channel HE-TFETs with a gate length LG of 25 nm and a LT-H of 5 nm achieve a 7 and 9 times ION improvement in comparison with the homo devices, respectively, at a supply voltage of 0.3 V. The performance enhancement in HE-TFETs is attributed to the modulating effect of heterojunction on band-to-band tunneling (BTBT). Because InN/In0.75Ga0.25N heterointerface shows the similar band offsets at conduction and valence bands, the InN/In0.75Ga0.25N heterojunction exhibits the improved effect on BTBT for both n- and p-channel devices. This makes InN/In0.75Ga0.25N heterojunction a promising structure for high performance complementary TFETs.

Behavior change through automated e-mails: mediation analysis of self-help strategy use for depressive symptoms.

PubMed

Morgan, Amy J; Mackinnon, Andrew J; Jorm, Anthony F

2013-02-01

To evaluate whether automated e-mails promoting effective self-help strategies for depressive symptoms were effective in changing self-help behavior, and whether this improved depression outcomes. 568 adults with sub-threshold depression participated in a randomized controlled trial and provided complete data. A series of 12 e-mails promoting the use of evidence-based self-help strategies was compared with e-mails providing non-directive depression information. Depression symptoms were assessed with the Patient Health Questionnaire depression scale (PHQ-9) and use of self-help strategies was assessed at baseline and post-intervention. We hypothesized that those receiving the self-help e-mails would increase their use of evidence-based self-help and this would be associated with improvements in depression. Mediation analyses were conducted using a non-parametric bootstrapping procedure. Total use of the self-help strategies promoted in the e-mails significantly mediated the effect of the intervention on depressive symptoms (B = -0.75, SE = 0.16, 95% CI: -1.06 to -0.48). The direct effect of the intervention on depressive symptoms was much smaller and not significant when the mediation path was included. The majority of the individual strategies also had a significant indirect effect on depressive symptoms. In adults with sub-threshold depression, automated e-mails based on behavior change principles can successfully increase use of self-help strategies, leading to a reduction in depressive symptoms. Copyright © 2012 Elsevier Ltd. All rights reserved.

Study of Gaussian Doped Double Gate JunctionLess (GD-DG-JL) transistor including source drain depletion length: Model for sub-threshold behavior

NASA Astrophysics Data System (ADS)

Kumari, Vandana; Kumar, Ayush; Saxena, Manoj; Gupta, Mridula

2018-01-01

The sub-threshold model formulation of Gaussian Doped Double Gate JunctionLess (GD-DG-JL) FET including source/drain depletion length is reported in the present work under the assumption that the ungated regions are fully depleted. To provide deeper insight into the device performance, the impact of gaussian straggle, channel length, oxide and channel thickness and high-k gate dielectric has been studied using extensive TCAD device simulation.

Subthreshold parallel pumping experiments on the quasi one-dimensional S = {1}/{2} ferromagnets [C 6H 11NH 3]CuBr 3 and [C 6H 11NH 3]CuCl 3

NASA Astrophysics Data System (ADS)

Hoogerbeets, R.; Wiegers, S. A. J.; Van Duyneveldt, A. J.

1985-04-01

Subthreshold parallel pumping experiments on [C 6H 11NH 3]CuBr 3 (abbreviated as CHAB) and [C 6H 11NH 3]CuCl 3 (CHAC) at 9.6 and 18.3 GHz are reported. It is shown that the experimental results can be explained using the values of the parameters as have been obtained from previously reported FMR measurements.

Trilayer TMDC Heterostructures for MOSFETs and Nanobiosensors

NASA Astrophysics Data System (ADS)

Datta, Kanak; Shadman, Abir; Rahman, Ehsanur; Khosru, Quazi D. M.

2017-02-01

Two dimensional materials such as transition metal dichalcogenides (TMDC) and their bi-layer/tri-layer heterostructures have become the focus of intense research and investigation in recent years due to their promising applications in electronics and optoelectronics. In this work, we have explored device level performance of trilayer TMDC heterostructure (MoS2/MX2/MoS2; M = Mo or, W and X = S or, Se) metal oxide semiconductor field effect transistors (MOSFETs) in the quantum ballistic regime. Our simulation shows that device `on' current can be improved by inserting a WS2 monolayer between two MoS2 monolayers. Application of biaxial tensile strain reveals a reduction in drain current which can be attributed to the lowering of carrier effective mass with increased tensile strain. In addition, it is found that gate underlap geometry improves electrostatic device performance by improving sub-threshold swing. However, increase in channel resistance reduces drain current. Besides exploring the prospect of these materials in device performance, novel trilayer TMDC heterostructure double gate field effect transistors (FETs) are proposed for sensing Nano biomolecules as well as for pH sensing. Bottom gate operation ensures these FETs operating beyond Nernst limit of 59 mV/pH. Simulation results found in this work reveal that scaling of bottom gate oxide results in better sensitivity while top oxide scaling exhibits an opposite trend. It is also found that, for identical operating conditions, proposed TMDC FET pH sensors show super-Nernst sensitivity indicating these materials as potential candidates in implementing such sensor. Besides pH sensing, all these materials show high sensitivity in the sub-threshold region as a channel material in nanobiosensor while MoS2/WS2/MoS2 FET shows the least sensitivity among them.

Modeling and characterization of the low frequency noise behavior for amorphous InGaZnO thin film transistors in the subthreshold region

NASA Astrophysics Data System (ADS)

Cai, Minxi; Yao, Ruohe

2017-10-01

An analytical model of the low-frequency noise (LFN) for amorphous InGaZnO (a-IGZO) thin film transistors (TFTs) in the subthreshold region is developed. For a-IGZO TFTs, relations between the device noise and the subgap defects are characterized based on the dominant multiple trapping and release (MTR) mechanism. The LFN is considered to be contributed from trapping/detrapping of carriers both into the border traps and the subgap density of states (DOS). It is revealed that the LFN behavior of a-IGZO TFTs in the subthreshold region is significantly influenced by the distribution of tail states, where MTR process prevails. The 1/f α (with α < 1) spectrum of the drain current noise is also related to the characteristic temperature of the tail states. The new method is introduced to calculate the LFN of devices by extracting the LFN-related DOS parameters from the current-voltage characteristics.

Subthreshold SPICE Model Optimization

NASA Astrophysics Data System (ADS)

Lum, Gregory; Au, Henry; Neff, Joseph; Bozeman, Eric; Kamin, Nick; Shimabukuro, Randy

2011-04-01

The first step in integrated circuit design is the simulation of said design in software to verify proper functionally and design requirements. Properties of the process are provided by fabrication foundries in the form of SPICE models. These SPICE models contain the electrical data and physical properties of the basic circuit elements. A limitation of these models is that the data collected by the foundry only accurately model the saturation region. This is fine for most users, but when operating devices in the subthreshold region they are inadequate for accurate simulation results. This is why optimizing the current SPICE models to characterize the subthreshold region is so important. In order to accurately simulate this region of operation, MOSFETs of varying widths and lengths are fabricated and the electrical test data is collected. From the data collected the parameters of the model files are optimized through parameter extraction rather than curve fitting. With the completed optimized models the circuit designer is able to simulate circuit designs for the sub threshold region accurately.

Risk factors predicting onset and persistence of subthreshold expression of bipolar psychopathology among youth from the community.

PubMed

Tijssen, M J A; Van Os, J; Wittchen, H U; Lieb, R; Beesdo, K; Wichers, Marieke

2010-09-01

To examine factors increasing the risk for onset and persistence of subthreshold mania and depression. In a prospective cohort community study, the association between risk factors [a family history of mood disorders, trauma, substance use, attention-deficit/hyperactivity disorder (ADHD) and temperamental/personality traits] and onset of manic/depressive symptoms was determined in 705 adolescents. The interaction between baseline risk factors and baseline symptoms in predicting 8-year follow-up symptoms was used to model the impact of risk factors on persistence. Onset of manic symptoms was associated with cannabis use and novelty seeking (NS), but NS predicted a transitory course. Onset of depressive symptoms was associated with a family history of depression. ADHD and harm avoidance (HA) were associated with persistence of depressive symptoms, while trauma and a family history of depression predicted a transitory course. Different risk factors may operate during onset and persistence of subthreshold mania and depression. The differential associations found for mania and depression dimensions suggest partly different underlying mechanisms.

On the applicability of the Natori formula to realistic multi-layer quantum well III-V FETs

NASA Astrophysics Data System (ADS)

Gili, A.; Xanthakis, J. P.

2017-10-01

We investigated the validity of the Natori formalism for realistic multi-layer quantum well FETs. We show that the assumption of a single layer (the channel) carrying all of the current density is far from reality in the sub-threshold region, where in fact most of the current density resides below the channel. Our analysis is based on comparing results of Natori calculations with experimental ones and on comparing with other first-principles calculations. If the Natori calculations are employed in the subthreshold region then a misleadingly small subthreshold slope would be obtained. We propose a way to remedy this inefficiency of this formulation so that it can be applicable to realistic many-layer devices. In particular we show that if the 1-dimensional quantum well of the Natori method enclosing the electron gas is expanded to include the supply layer-usually below the channel- and a proper ab initio potential is used to obtain its eigenvalues, then the Natori formula regains its validity.

Hypertriton and light nuclei production at Λ-production subthreshold energy in heavy-ion collisions

NASA Astrophysics Data System (ADS)

Zhang, Song; Chen, Jin-Hui; Ma, Yu-Gang; Xu, Zhang-Bu; Cai, Xiang-Zhou; Ma, Guo-Liang; Zhong, Chen

2011-08-01

High-energy heavy-ion collisions produce abundant hyperons and nucleons. A dynamical coalescence model coupled with the ART model is employed to study the production probabilities of light clusters, deuteron (d), triton (t), helion (3He), and hypertriton (3ΛH) at subthreshold energy of Aproduction (≈ 1 GeV per nucleon). We study the dependence on the reaction system size of the coalescence penalty factor per additional nucleon and entropy per nucleon. The Strangeness Population Factor shows an extra suppression of hypertriton comparing to light clusters of the same mass number. This model predicts a hypertriton production cross-section of a few μb in 36Ar+36Ar, 40Ca+40Ca and 56Ni+56Ni in 1 A GeV reactions. The production rate is as high as a few hypertritons per million collisions, which shows that the fixed-target heavy-ion collisions at CSR (Lanzhou/China) at Λ subthreshold energy are suitable for breaking new ground in hypernuclear physics.

Oscillations emerging from noise-driven steady state in networks with electrical synapses and subthreshold resonance

PubMed Central

Tchumatchenko, Tatjana; Clopath, Claudia

2014-01-01

Oscillations play a critical role in cognitive phenomena and have been observed in many brain regions. Experimental evidence indicates that classes of neurons exhibit properties that could promote oscillations, such as subthreshold resonance and electrical gap junctions. Typically, these two properties are studied separately but it is not clear which is the dominant determinant of global network rhythms. Our aim is to provide an analytical understanding of how these two effects destabilize the fluctuation-driven state, in which neurons fire irregularly, and lead to an emergence of global synchronous oscillations. Here we show how the oscillation frequency is shaped by single neuron resonance, electrical and chemical synapses.The presence of both gap junctions and subthreshold resonance are necessary for the emergence of oscillations. Our results are in agreement with several experimental observations such as network responses to oscillatory inputs and offer a much-needed conceptual link connecting a collection of disparate effects observed in networks. PMID:25405458

Structural-modification mechanism for polyimide-doped poly(tetrafluoroethylene)at subthreshold fluences using 248 nm radiation

NASA Astrophysics Data System (ADS)

Davis, C. R.; Snyder, R. W.; Egitto, F. D.; D'Couto, G. C.; Babu, S. V.

1994-09-01

Single-photon excimer laser ablation of neat poly(tetrafluoroethylene) (PTFE) is not observed at emissions in the 'quartz' UV, i.e., from about 190-380 nm. However, it has been successfully demonstrated that, when the fluoropolymer is doped with small quantities of polyimide (PI), ablation in the quartz UV, e.g., at 248 and 308 nm and pulse widths of about 25 ns, is readily achieved. When PI-PTFE blends are exposed to subthreshold fluences, considerable changes in surface topography occur although clearly defined structures, e.g., pits, are not formed. Using photoacoustic infrared spectroscopy to evaluate surface and bulk chemical changes to blends exposed to subthreshold excimer laser fluences, is less than 100 mJ/sq cm, it is shown that PI (1) is distributed throughout the bulk and resides at the surface and (2) is selectively absorbing the high-energy photons and as a result being preferentially removed from the surface.

Sensory evaluation of the synergism among odorants present in concentrations below their odor threshold in a Chinese jasmine green tea infusion.

PubMed

Ito, Yuriko; Kubota, Kikue

2005-01-01

The mechanism for the contribution of subthreshold aroma constituents to the overall jasmine tea odor impression was studied on the basis of a sensory evaluation. Binary model aqueous solutions containing the authentic odorants of a jasmine tea infusion, (E)-2-hexenyl hexanoate (I), (Z)-3-hexenol (II), and indole (III), were each prepared in a concentration below the odor threshold. Each solution had no aroma, but when 4-hexanolide replaced only 5% of each odorant, the odor intensity of each model solution was significantly strengthened. An astringent note and heavy note were recognized for each solution as the commonly perceived characteristics from the sensory evaluation. The concentration of 4-hexanolide added was also at the subthreshold level. The results suggest mutual interaction between odorants I, II, or III and 4-hexanolide. The effect on the overall odor sensation of a jasmine tea infusion by adding 4-hexanolide at a concentration below its odor threshold was also studied. In this case, the intensity of both the sweet and astringent notes was significantly strengthened in comparison with the odor impression of the original jasmine tea infusion. This phenomenon is considered to have been a synergistic effect between subthreshold odor compounds in the jasmine tea infusion. The results of this study clarify for the first time that the subthreshold aroma constituents play an important role in the characteristic flavor of a jasmine tea infusion.

Metal-induced crystallization of amorphous zinc tin oxide semiconductors for high mobility thin-film transistors

NASA Astrophysics Data System (ADS)

Hwang, Ah Young; Kim, Sang Tae; Ji, Hyuk; Shin, Yeonwoo; Jeong, Jae Kyeong

2016-04-01

Transition tantalum induced crystallization of amorphous zinc tin oxide (a-ZTO) was observed at low temperature annealing of 300 °C. Thin-film transistors (TFTs) with an a-ZTO channel layer exhibited a reasonable field-effect mobility of 12.4 cm2/V s, subthreshold swing (SS) of 0.39 V/decade, threshold voltage (VTH) of 1.5 V, and ION/OFF ratio of ˜107. A significant improvement in the field-effect mobility (up to ˜33.5 cm2/V s) was achieved for crystallized ZTO TFTs: this improvement was accomplished without compromising the SS, VTH, or ION/OFF ratio due to the presence of a highly ordered microstructure.

Proportion of patients without mental disorders being treated in mental health services worldwide

PubMed Central

Bruffaerts, Ronny; Posada-Villa, Jose; Al-Hamzawi, Ali Obaid; Gureje, Oye; Huang, Yueqin; Hu, Chiyi; Bromet, Evelyn J.; Viana, Maria Carmen; Hinkov, Hristo Ruskov; Karam, Elie G.; Borges, Guilherme; Florescu, Silvia E.; Williams, David R.; Demyttenaere, Koen; Kovess-Masfety, Viviane; Matschinger, Herbert; Levinson, Daphna; de Girolamo, Giovanni; Ono, Yutaka; de Graaf, Ron; Browne, Mark Oakley; Bunting, Brendan; Xavier, Miguel; Haro, Josep Maria; Kessler, Ronald C.

2015-01-01

Background Previous research suggests that many people receiving mental health treatment do not meet criteria for a mental disorder but are rather ‘the worried well’. Aims To examine the association of past-year mental health treatment with DSM-IV disorders. Method The World Health Organization’s World Mental Health (WMH) Surveys interviewed community samples of adults in 23 countries (n = 62 305) about DSM-IV disorders and treatment in the past 12 months for problems with emotions, alcohol or drugs. Results Roughly half (52%) of people who received treatment met criteria for a past-year DSM-IV disorder, an additional 18% for a lifetime disorder and an additional 13% for other indicators of need (multiple subthreshold disorders, recent stressors or suicidal behaviours). Dose-response associations were found between number of indicators of need and treatment. Conclusions The vast majority of treatment in the WMH countries goes to patients with mental disorders or other problems expected to benefit from treatment. PMID:25395690

Integrated digital inverters based on two-dimensional anisotropic ReS₂ field-effect transistors

DOE PAGES

Liu, Erfu; Fu, Yajun; Wang, Yaojia; ...

2015-05-07

Semiconducting two-dimensional transition metal dichalcogenides are emerging as top candidates for post-silicon electronics. While most of them exhibit isotropic behaviour, lowering the lattice symmetry could induce anisotropic properties, which are both scientifically interesting and potentially useful. Here we present atomically thin rhenium disulfide (ReS₂) flakes with unique distorted 1T structure, which exhibit in-plane anisotropic properties. We fabricated monolayer and few-layer ReS₂ field-effect transistors, which exhibit competitive performance with large current on/off ratios (~10⁷) and low subthreshold swings (100 mV per decade). The observed anisotropic ratio along two principle axes reaches 3.1, which is the highest among all known two-dimensional semiconductingmore » materials. Furthermore, we successfully demonstrated an integrated digital inverter with good performance by utilizing two ReS₂ anisotropic field-effect transistors, suggesting the promising implementation of large-scale two-dimensional logic circuits. Our results underscore the unique properties of two-dimensional semiconducting materials with low crystal symmetry for future electronic applications.« less

Older people, the natural environment and common mental disorders: cross-sectional results from the Cognitive Function and Ageing Study

PubMed Central

Wu, Yu-Tzu; Prina, A Matthew; Jones, Andy; Matthews, Fiona E; Brayne, Carol

2015-01-01

Objectives To explore the hypothesis that higher exposure to natural environments in local areas is associated with a lower odds of depression and anxiety in later life. Design A cross-sectional study based on the year-10 interview of the Medical Research Council Cognitive Function and Ageing Study (CFAS), a population-based study of ageing in the UK. Postcodes of the CFAS participants were mapped onto small geographic units, lower-layer super output areas (LSOAs) and linked to environmental data from government databases. The natural environment was characterised as the percentage of green space and private gardens in each LSOA based on the UK Generalised Land Use 2001 Dataset. Participants 2424 people aged 74 and over in the CFAS year-10 follow-up interview (2001) from 4 English centres (Cambridgeshire, Nottingham, Newcastle and Oxford). Main outcome measures Depression and anxiety; clinical and subthreshold cases were identified using the Geriatric Mental State Examination (GMS) package and its associated diagnostic algorithm: the Automated Geriatric Examination for Computer Assisted Taxonomy. Results Compared with the lowest quartile, living in the highest quartile of neighbourhood natural environment provision was associated with a reduced odds of subthreshold depression (OR 0.66, 95% CI 0.46 to 0.95), anxiety symptoms (OR 0.62, 95% CI 0.46 to 0.83) and their co-occurrence (OR 0.55, 95% CI 0.35 to 0.84) after adjusting for individual-level factors. Controlling for area deprivation attenuated the strength of associations for subthreshold depression by 20% but not for anxiety symptoms or for co-occurrence of the conditions. Conclusions A high exposure to natural environments (green space and gardens) in communities was associated with fewer mental disorders among older people. Increasing provision of green environments in local areas could be a potential population-level intervention to improve mental health among older people. PMID:26377504

A micropower electrocardiogram amplifier.

PubMed

Fay, L; Misra, V; Sarpeshkar, R

2009-10-01

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.

Using KrF ELA to Improve Gate-Stacked LaAlO₃/ZrO₂ Indium Gallium Zinc Oxide Thin-Film Transistors with Novel Atmospheric Pressure Plasma-Enhanced Chemical Vapor Deposition Technique.

PubMed

Wu, Chien-Hung; Chang, Kow-Ming; Chen, Yi-Ming; Huang, Bo-Wen; Zhang, Yu-Xin; Wang, Shui-Jinn

2018-03-01

Atmospheric pressure plasma-enhanced chemical vapor deposition (AP-PECVD) technique and KrF excimer laser annealing (ELA) were employed for the fabrication of indium gallium zinc oxide thin-film transistors (IGZO-TFTs). Device with a 150 mJ/cm2 laser annealing densities demonstrated excellent electrical characteristics with improved on/off current ratio of 4.7×107, high channel mobility of 10 cm2/V-s, and low subthreshold swing of 0.15 V/dec. The improvements are attributed to the adjustment of oxygen vacancies in the IGZO channel to an appropriate range of around 28.3% and the reduction of traps at the high-k/IGZO interface.

Low-Voltage InGaZnO Thin Film Transistors with Small Sub-Threshold Swing.

PubMed

Cheng, C H; Chou, K I; Hsu, H H

2015-02-01

We demonstrate a low-voltage driven, indium-gallium-zinc oxide thin-film transistor using high-κ LaAlO3 gate dielectric. A low VT of 0.42 V, very small sub-threshold swing of 68 mV/dec, field-effect mobility of 4.1 cm2/Ns and low operation voltage of 1.4 V were reached simultaneously in LaAlO3/IGZO TFT device. This low-power and small SS TFT has the potential for fast switching speed and low power applications.

Effects of an Internet-Based Cognitive Behavioral Therapy (iCBT) Program in Manga Format on Improving Subthreshold Depressive Symptoms among Healthy Workers: A Randomized Controlled Trial

PubMed Central

Imamura, Kotaro; Kawakami, Norito; Furukawa, Toshi A.; Matsuyama, Yutaka; Shimazu, Akihito; Umanodan, Rino; Kawakami, Sonoko; Kasai, Kiyoto

2014-01-01

Objective The purpose of this study was to develop a new Internet-based computerized cognitive behavior therapy (iCBT) program in Manga format, the Japanese cartoon, for workers and to examine the effects of the iCBT program on improving subthreshold depression using a randomized controlled trial (RCT) design among workers employed in private companies in Japan. Method All workers in a company (n = 290) and all workers in three departments (n = 1,500) at the headquarters of another large company were recruited by an invitation e-mail. Participants who fulfilled the inclusion criteria were randomly allocated to intervention or control groups (N = 381 for each group). A six-week, six-lesson iCBT program using Manga (Japanese comic) story was developed. The program included several CBT skills: self-monitoring, cognitive restructuring, assertiveness, problem solving, and relaxation. The intervention group studied the iCBT program at a frequency of one lesson per week. Depression (Beck Depression Inventory II; BDI-II) was assessed as a primary outcome at baseline, and three- and six-month follow-ups for both intervention and control groups were performed. Results The iCBT program showed a significant intervention effect on BDI-II (t = −1.99, p<0.05) with small effect sizes (Cohen's d: −0.16, 95% Confidence Interval: −0.32 to 0.00, at six-month follow-up). Conclusions The present study first demonstrated that a computerized cognitive behavior therapy delivered via the Internet was effective in improving depression in the general working population. It seems critical to improve program involvement of participants in order to enhance the effect size of an iCBT program. Trial Registration UMIN Clinical Trials Registry UMIN000006210 PMID:24844530

Regulation of Local Ambient GABA Levels via Transporter-Mediated GABA Import and Export for Subliminal Learning.

PubMed

Hoshino, Osamu

2015-06-01

Perception of supraliminal stimuli might in general be reflected in bursts of action potentials (spikes), and their memory traces could be formed through spike-timing-dependent plasticity (STDP). Memory traces for subliminal stimuli might be formed in a different manner, because subliminal stimulation evokes a fraction (but not a burst) of spikes. Simulations of a cortical neural network model showed that a subliminal stimulus that was too brief (10 msec) to perceive transiently (more than about 500 msec) depolarized stimulus-relevant principal cells and hyperpolarized stimulus-irrelevant principal cells in a subthreshold manner. This led to a small increase or decrease in ongoing-spontaneous spiking activity frequency (less than 1 Hz). Synaptic modification based on STDP during this period effectively enhanced relevant synaptic weights, by which subliminal learning was improved. GABA transporters on GABAergic interneurons modulated local levels of ambient GABA. Ambient GABA molecules acted on extrasynaptic receptors, provided principal cells with tonic inhibitory currents, and contributed to achieving the subthreshold neuronal state. We suggest that ongoing-spontaneous synaptic alteration through STDP following subliminal stimulation may be a possible neuronal mechanism for leaving its memory trace in cortical circuitry. Regulation of local ambient GABA levels by transporter-mediated GABA import and export may be crucial for subliminal learning.

Low-power circuits design for the wireless force measurement system of the total knee arthroplasty.

PubMed

Chen, Hong; Liu, Ming; Wan, Weiyi; Jia, Chen; Zhang, Chun; Wang, Zihua

2010-01-01

This paper proposes a novel wireless force measurement system for the Total Knee Arthroplasty (TKA) to improve the ligament balancing procedure during TKA. The force measurement system is comprised of a Wireless Force Measurement Spacer (WFMS) and the display part. They communicate with each other by the Radio Frequency (RF) signal. The WFMS is designed to measure the force between the WFMS and the femoral component of the artificial implants and to transmit the force data wirelessly by a low power transceiver. The display part demonstrates the force data in 3D images in real time. The WFMS composes of a sensors array, a Universal Transducer Interfaces (UTIs) array, a low-power sub-threshold microprocessor and a transceiver. The sub-threshold 8-bit microprocessor is taped out with 0.18 microm CMOS technology. The testing results of the microprocessor show that the leakage power of 46nW and the dynamic power of 385nW@165kHz are achieved with the operating voltage of 350 mV. The test results of the system are given and the errors of the system are analyzed. The results verified the reliability of the system. The future work is to design the microprocessor and a lower power transceiver within a single chip.

Study of fully-depleted Ge double-gate n-type Tunneling Field-Effect Transistors for improvement in on-state current and sub-threshold swing

NASA Astrophysics Data System (ADS)

Liu, Xiangyu; Hu, Huiyong; Wang, Meng; Zhang, Heming; Cui, Shimin; Shu, Bin; Wang, Bin

2018-01-01

In this paper, a fully-depleted (FD) Ge double-gate (DG) n-type Tunneling Field-Effect Transistors (TFET) structure is studied in detail by two-dimensional numerical simulation. The simulation results indicated that the on-state current Ion and on-off ratio of the FD Ge DG-TFET increases about 1 order of magnitude comparing with the Conventional Ge DG-TFET, and Ion=3.95×10-5 A/μm and the below 60 mV/decade subthreshold swing S=26.4 mV/decade are achieved with the length of gate LD=20 nm, the workfuntion of metal gate Φm=0.2 eV and the doping concentration of n+-type-channel ND=1×1018 cm-3. Moreover, the impacts of Φm, ND and LD are investigated. The simulation results indicated that the off-state current Ioff includes the tunneling current at the middle of channel IB the gated-induced drain leakage (GIDL) current IGIDL. With optimized Φm and ND, Ioff is reduced about 2 orders of magnitude to 2.5×10-13 A/μm with LD increasing from 40 nm to 100 nm, and on-off ratio is increased to 1.58×107.

Agmatine potentiates neuroprotective effects of subthreshold concentrations of ketamine via mTOR/S6 kinase signaling pathway.

PubMed

Tavares, Mauren K; Dos Reis, Suellen; Platt, Nicolle; Heinrich, Isabella A; Wolin, Ingrid A V; Leal, Rodrigo B; Kaster, Manuella P; Rodrigues, Ana Lúcia S; Freitas, Andiara E

2018-05-12

Dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is one of the most robust neurobiological findings in the pathophysiology of major depressive disorder (MDD) over the last 40 years. The persistent increase in glucocorticoids levels induces morphological and anatomical changes in the brain, especially in the hippocampus. Ketamine represents a major advance for the treatment of MDD, however the psychotomimetic effects of this compound limit its widespread use. Agmatine is a neuromodulator that has been shown to be a putative novel and well-tolerated antidepressant/augmenter drug. In this study, the exposure of HT22 hippocampal neuronal cell line to corticosterone (50 μM) induced a significant neuronal cell death. Interestingly, the incubation of HT22 cells with the fast-acting antidepressant drug ketamine (1 μM) prevented the corticosterone-induced toxicity. Similarly, agmatine caused a significant cytoprotection at the concentration of 0.1 μM against corticosterone (50 μM) cell damage. Notably, the incubation with a subthreshold concentration of ketamine (0.01 μM) in combination with a subthreshold concentration of agmatine (0.001 μM) prevented the neuronal damage elicited by corticosterone (50 μM). A 24 h co-incubation with subthreshold concentrations of ketamine (0.01 μM) and agmatine (0.001 μM) was able to cause a significant increase in the phosphorylation levels of Akt (Ser 473 ) and p70S6 kinase (Thr 389 ) as well as PSD95 immunocontent. Neither glycogen synthase kinase-3β (Ser 9 ) phosphorylation nor β catenin immunocontent were altered by a 24 h co-incubation period. Finally, the co-incubation of cells for 30 min did not produce any effect in the phosphorylation or immunocontent of any protein investigated. Taken together, our results support the notion that the combination of subthreshold concentrations of ketamine and agmatine has cytoprotective effects against corticosterone-induced cell death. This effect is accompanied by its ability to activate Akt and mTOR/S6 kinase signaling pathway, and increase the expression of synaptic proteins. Copyright © 2018. Published by Elsevier Ltd.

Telephone Cognitive-Behavioral Therapy for Subthreshold Depression and Presenteeism in Workplace: A Randomized Controlled Trial

PubMed Central

Furukawa, Toshi A.; Horikoshi, Masaru; Kawakami, Norito; Kadota, Masayo; Sasaki, Megumi; Sekiya, Yuki; Hosogoshi, Hiroki; Kashimura, Masami; Asano, Kenichi; Terashima, Hitomi; Iwasa, Kazunori; Nagasaku, Minoru; Grothaus, Louis C.

2012-01-01

Background Subthreshold depression is highly prevalent in the general population and causes great loss to society especially in the form of reduced productivity while at work (presenteeism). We developed a highly-structured manualized eight-session cognitive-behavioral program with a focus on subthreshold depression in the workplace and to be administered via telephone by trained psychotherapists (tCBT). Methods We conducted a parallel-group, non-blinded randomized controlled trial of tCBT in addition to the pre-existing Employee Assistance Program (EAP) versus EAP alone among workers with subthreshold depression at a large manufacturing company in Japan. The primary outcomes were depression severity as measured with Beck Depression Inventory-II (BDI-II) and presenteeism as measured with World Health Organization Health and Work Productivity Questionnaire (HPQ). In the course of the trial the follow-up period was shortened in order to increase acceptability of the study. Results The planned sample size was 108 per arm but the trial was stopped early due to low accrual. Altogether 118 subjects were randomized to tCBT+EAP (n = 58) and to EAP alone (n = 60). The BDI-II scores fell from the mean of 17.3 at baseline to 11.0 in the intervention group and to 15.7 in the control group after 4 months (p<0.001, Effect size = 0.69, 95%CI: 0.32 to 1.05). However, there was no statistically significant decrease in absolute and relative presenteeism (p = 0.44, ES = 0.15, −0.21 to 0.52, and p = 0.50, ES = 0.02, −0.34 to 0.39, respectively). Conclusion Remote CBT, including tCBT, may provide easy access to quality-assured effective psychotherapy for people in the work force who present with subthreshold depression. Further studies are needed to evaluate the effectiveness of this approach in longer terms. The study was funded by Sekisui Chemicals Co. Ltd. Trial Registration ClinicalTrials.gov NCT00885014 PMID:22532849

Association between Maternal Depression Symptoms across the First Eleven Years of Their Child’s Life and Subsequent Offspring Suicidal Ideation

PubMed Central

Hammerton, Gemma; Mahedy, Liam; Mars, Becky; Harold, Gordon T.; Thapar, Anita; Zammit, Stanley; Collishaw, Stephan

2015-01-01

Depression is common, especially in women of child-bearing age; prevalence estimates for this group range from 8% to 12%, and there is robust evidence that maternal depression is associated with mental health problems in offspring. Suicidal behaviour is a growing concern amongst young people and those exposed to maternal depression are likely to be especially at high risk. The aim of this study was to utilise a large, prospective population cohort to examine the relationship between depression symptom trajectories in mothers over the first eleven years of their child’s life and subsequent adolescent suicidal ideation. An additional aim was to test if associations were explained by maternal suicide attempt and offspring depressive disorder. Data were utilised from a population-based birth cohort: the Avon Longitudinal Study of Parents and Children. Maternal depression symptoms were assessed repeatedly from pregnancy to child age 11 years. Offspring suicidal ideation was assessed at age 16 years. Using multiple imputation, data for 10,559 families were analysed. Using latent class growth analysis, five distinct classes of maternal depression symptoms were identified (minimal, mild, increasing, sub-threshold, chronic-severe). The prevalence of past-year suicidal ideation at age 16 years was 15% (95% CI: 14-17%). Compared to offspring of mothers with minimal symptoms, the greatest risk of suicidal ideation was found for offspring of mothers with chronic-severe symptoms [OR 3.04 (95% CI 2.19, 4.21)], with evidence for smaller increases in risk of suicidal ideation in offspring of mothers with sub-threshold, increasing and mild symptoms. These associations were not fully accounted for by maternal suicide attempt or offspring depression diagnosis. Twenty-six percent of non-depressed offspring of mothers with chronic-severe depression symptoms reported suicidal ideation. Risk for suicidal ideation should be considered in young people whose mothers have a history of sustained high levels of depression symptoms, even when the offspring themselves do not have a depression diagnosis. PMID:26151929

In vitro Neurons in Mammalian Cortical Layer 4 Exhibit Intrinsic Oscillatory Activity in the 10- to 50-Hz Frequency Range

NASA Astrophysics Data System (ADS)

Llinas, Rodolfo R.; Grace, Anthony A.; Yarom, Yosef

1991-02-01

We report here the presence of fast subthreshold oscillatory potentials recorded in vitro from neurons within layer 4 of the guinea pig frontal cortex. Two types of oscillatory neurons were recorded: (i) One type exhibited subthreshold oscillations whose frequency increased with membrane depolarization and encompassed a range of 10-45 Hz. Action potentials in this type of neuron demonstrated clear after-hyperpolarizations. (ii) The second type of neuron was characterized by narrow-frequency oscillations near 35-50 Hz. These oscillations often outlasted the initiating depolarizing stimulus. No calcium component could be identified in their action potential. In both types of cell the subthreshold oscillations were tetrodotoxin-sensitive, indicating that the depolarizing phase of the oscillation was generated by a voltage-dependent sodium conductance. The initial depolarizing phase was followed by a potassium conductance responsible for the falling phase of the oscillatory wave. In both types of cell, the subthreshold oscillation could trigger spikes at the oscillatory frequency, if the membrane was sufficiently depolarized. Combining intracellular recordings with Lucifer yellow staining showed that the narrow-frequency oscillatory activity was produced by a sparsely spinous interneuron located in layer 4 of the cortex. This neuron has extensive local axonal collaterals that ramify in layers 3 and 4 such that they may contribute to the columnar synchronization of activity in the 40- to 50-Hz range. Cortical activity in this frequency range has been proposed as the basis for the "conjunctive properties" of central nervous system networks.

Prevalence, incidence, and natural course of anorexia and bulimia nervosa among adolescents and young adults.

PubMed

Nagl, Michaela; Jacobi, Corinna; Paul, Martin; Beesdo-Baum, Katja; Höfler, Michael; Lieb, Roselind; Wittchen, Hans-Ulrich

2016-08-01

We aimed to assess the prevalence, incidence, age-of-onset and diagnostic stability of threshold and subthreshold anorexia nervosa (AN) and bulimia nervosa (BN) in the community. Data come from a prospective-longitudinal community study of 3021 subjects aged 14-24 at baseline, who were followed up at three assessment waves over 10 years. Eating disorder (ED) symptomatology was assessed with the DSM-IV/M-CIDI at each wave. Diagnostic stability was defined as the proportion of individuals still affected with at least symptomatic eating disorders (EDs) at follow-ups. Baseline lifetime prevalence for any threshold ED were 2.9 % among females and 0.1 % among males. For any subthreshold ED lifetime prevalence were 2.2 % for females and 0.7 % for males. Symptomatic expressions of EDs (including core symptoms of the respective disorder) were most common with a lifetime prevalence of 11.5 % among females and 1.8 % among males. Symptomatic AN showed the earliest onset with a considerable proportion of cases emerging in childhood. 47 % of initial threshold AN cases and 42 % of initial threshold BN cases showed at least symptomatic expressions of any ED at any follow-up assessment. Stability for subthreshold EDs and symptomatic expressions was 14-36 %. While threshold EDs are rare, ED symptomatology is common particularly in female adolescents and young women. Especially threshold EDs are associated with a substantial risk for stability. A considerable degree of symptom fluctuation is characteristic especially for subthreshold EDs.

Modulation of hippocampal rhythms by subthreshold electric fields and network topology

PubMed Central

Berzhanskaya, Julia; Chernyy, Nick; Gluckman, Bruce J.; Schiff, Steven J.; Ascoli, Giorgio A.

2012-01-01

Theta (4–12 Hz) and gamma (30–80 Hz) rhythms are considered important for cortical and hippocampal function. Although several neuron types are implicated in rhythmogenesis, the exact cellular mechanisms remain unknown. Subthreshold electric fields provide a flexible, area-specific tool to modulate neural activity and directly test functional hypotheses. Here we present experimental and computational evidence of the interplay among hippocampal synaptic circuitry, neuronal morphology, external electric fields, and network activity. Electrophysiological data are used to constrain and validate an anatomically and biophysically realistic model of area CA1 containing pyramidal cells and two interneuron types: dendritic- and perisomatic-targeting. We report two lines of results: addressing the network structure capable of generating theta-modulated gamma rhythms, and demonstrating electric field effects on those rhythms. First, theta-modulated gamma rhythms require specific inhibitory connectivity. In one configuration, GABAergic axo-dendritic feedback on pyramidal cells is only effective in proximal but not distal layers. An alternative configuration requires two distinct perisomatic interneuron classes, one exclusively receiving excitatory contacts, the other additionally targeted by inhibition. These observations suggest novel roles for particular classes of oriens and basket cells. The second major finding is that subthreshold electric fields robustly alter the balance between different rhythms. Independent of network configuration, positive electric fields decrease, while negative fields increase the theta/gamma ratio. Moreover, electric fields differentially affect average theta frequency depending on specific synaptic connectivity. These results support the testable prediction that subthreshold electric fields can alter hippocampal rhythms, suggesting new approaches to explore their cognitive functions and underlying circuitry. PMID:23053863

Abnormality of G-protein-coupled receptor kinases at prodromal and early stages of Alzheimer's disease: an association with early beta-amyloid accumulation.

PubMed

Suo, Zhiming; Wu, Min; Citron, Bruce A; Wong, Gwendolyn T; Festoff, Barry W

2004-03-31

Overwhelming evidence indicates that the effects of beta-amyloid (Abeta) are dose dependent both in vitro and in vivo, which implies that Abeta is not directly detrimental to brain cells until it reaches a threshold concentration. In an effort to understand early Alzheimer's disease (AD) pathogenesis, this study focused on the effects of subthreshold soluble Abeta and the underlying molecular mechanisms in murine microglial cells and an AD transgenic mouse model. We found that there were two phases of dose-dependent Abeta effects on microglial cells: at the threshold of 5 microm and above, Abeta directly induced tumor necrosis factor-alpha (TNF-alpha) release, and at subthreshold doses, Abeta indirectly potentiated TNF-alpha release induced by certain G-protein-coupled receptor (GPCR) activators. Mechanistic studies revealed that subthreshold Abeta pretreatment in vitro reduced membrane GPCR kinase-2/5 (GRK2/5), which led to retarded GPCR desensitization, prolonged GPCR signaling, and cellular hyperactivity to GPCR agonists. Temporal analysis in an early-onset AD transgenic model, CRND8 mice, revealed that the membrane (functional) GRK2/5 in brain cortices were significantly reduced. More importantly, such a GRK abnormality took place before cognitive decline and changed in a manner corresponding with the mild to moderate soluble Abeta accumulation in these transgenic mice. Together, this study not only discovered a novel link between subthreshold Abeta and GRK dysfunction, it also demonstrated that the GRK abnormality in vivo occurs at prodromal and early stages of AD.

Heterogeneity of amygdala response in major depressive disorder: the impact of lifetime subthreshold mania.

PubMed

Fournier, J C; Keener, M T; Mullin, B C; Hafeman, D M; Labarbara, E J; Stiffler, R S; Almeida, J; Kronhaus, D M; Frank, E; Phillips, M L

2013-02-01

Patients with major depressive disorder (MDD) present with highly heterogeneous symptom profiles. We aimed to examine whether individual differences in amygdala activity to emotionally salient stimuli were related to heterogeneity in lifetime levels of depressive and subthreshold manic symptoms among adults with MDD. We compared age- and gender-matched adults with MDD (n = 26) with healthy controls (HC, n = 28). While undergoing functional magnetic resonance imaging, participants performed an implicit emotional faces task: they labeled a color flash superimposed upon initially neutral faces that dynamically morphed into one of four emotions (angry, fearful, sad, happy). Region of interest analyses examined group differences in amygdala activity. For conditions in which adults with MDD displayed abnormal amygdala activity versus HC, within-group analyses examined amygdala activity as a function of scores on a continuous measure of lifetime depression-related and mania-related pathology. Adults with MDD showed significantly greater right-sided amygdala activity to angry and happy conditions than HC (p < 0.05, corrected). Multiple regression analyses revealed that greater right-amygdala activity to the happy condition in adults with MDD was associated with higher levels of subthreshold manic symptoms experienced across the lifespan (p = 0.002). Among depressed adults with MDD, lifetime features of subthreshold mania were associated with abnormally elevated amygdala activity to emerging happy faces. These findings are a first step toward identifying biomarkers that reflect individual differences in neural mechanisms in MDD, and challenge conventional mood disorder diagnostic boundaries by suggesting that some adults with MDD are characterized by pathophysiological processes that overlap with bipolar disorder.

Reward abnormalities among women with full and subthreshold bulimia nervosa: a functional magnetic resonance imaging study.

PubMed

Bohon, Cara; Stice, Eric

2011-11-01

To test the hypothesis that women with full and subthreshold bulimia nervosa show abnormal neural activation in response to food intake and anticipated food intake relative to healthy control women. Females with and without full/subthreshold bulimia nervosa recruited from the community (N = 26) underwent functional magnetic resonance imaging (fMRI) during receipt and anticipated receipt of chocolate milkshake and a tasteless control solution. Women with bulimia nervosa showed trends for less activation than healthy controls in the right anterior insula in response to anticipated receipt of chocolate milkshake (vs. tasteless solution) and in the left middle frontal gyrus, right posterior insula, right precentral gyrus, and right mid dorsal insula in response to consumptions of milkshake (vs. tasteless solution). Bulimia nervosa may be related to potential hypofunctioning of the brain reward system, which may lead these individuals to binge eat to compensate for this reward deficit, though the hypo-responsivity might be a result of a history of binge eating highly palatable foods. Copyright © 2010 Wiley Periodicals, Inc.

Spacer engineered Trigate SOI TFET: An investigation towards harsh temperature environment applications

NASA Astrophysics Data System (ADS)

Mallikarjunarao; Ranjan, Rajeev; Pradhan, K. P.; Artola, L.; Sahu, P. K.

2016-09-01

In this paper, a novel N-channel Tunnel Field Effect Transistor (TFET) i.e., Trigate Silicon-ON-Insulator (SOI) N-TFET with high-k spacer is proposed for better Sub-threshold swing (SS) and OFF-state current (IOFF) by keeping in mind the sensitivity towards temperature. The proposed model can achieve a Sub-threshold swing less than 35 mV/decade at various temperatures, which is desirable for designing low power CTFET for digital circuit applications. In N-TFET source doping has a significant effect on the ON-state current (ION) level; therefore more electrons will tunnel from source to channel region. High-k Spacer i.e., HfO2 is used to enhance the device performance and also it avoids overlapping of transistors in an integrated circuits (IC's). We have designed a reliable device by performing the temperature analysis on Transfer characteristics, Drain characteristics and also on various performance metrics like ON-state current (ION), OFF-state current (IOFF), ION/IOFF, Trans-conductance (gm), Trans-conductance Generation Factor (TGF), Sub-threshold Swing (SS) to observe the applications towards harsh temperature environment.

Interspike interval correlation in a stochastic exponential integrate-and-fire model with subthreshold and spike-triggered adaptation.

PubMed

Shiau, LieJune; Schwalger, Tilo; Lindner, Benjamin

2015-06-01

We study the spike statistics of an adaptive exponential integrate-and-fire neuron stimulated by white Gaussian current noise. We derive analytical approximations for the coefficient of variation and the serial correlation coefficient of the interspike interval assuming that the neuron operates in the mean-driven tonic firing regime and that the stochastic input is weak. Our result for the serial correlation coefficient has the form of a geometric sequence and is confirmed by the comparison to numerical simulations. The theory predicts various patterns of interval correlations (positive or negative at lag one, monotonically decreasing or oscillating) depending on the strength of the spike-triggered and subthreshold components of the adaptation current. In particular, for pure subthreshold adaptation we find strong positive ISI correlations that are usually ascribed to positive correlations in the input current. Our results i) provide an alternative explanation for interspike-interval correlations observed in vivo, ii) may be useful in fitting point neuron models to experimental data, and iii) may be instrumental in exploring the role of adaptation currents for signal detection and signal transmission in single neurons.

Reward Abnormalities Among Women with Full and Subthreshold Bulimia Nervosa: A Functional Magnetic Resonance Imaging Study

PubMed Central

Bohon, Cara; Stice, Eric

2010-01-01

Objective To test the hypothesis that women with full and subthreshold bulimia nervosa show abnormal neural activation in response to food intake and anticipated food intake relative to healthy control women. Method Females with and without full/subthreshold bulimia nervosa recruited from the community (N = 26) underwent functional magnetic resonance imaging (fMRI) during receipt and anticipated receipt of chocolate milkshake and a tasteless control solution. Results Women with bulimia nervosa showed trends for less activation than healthy controls in the right anterior insula in response to anticipated receipt of chocolate milkshake (versus tasteless solution) and in the left middle frontal gyrus, right posterior insula, right precentral gyrus, and right mid dorsal insula in response to consumptions of milkshake (versus tasteless solution). Discussion Bulimia nervosa may be related to potential hypo-functioning of the brain reward system, which may lead these individuals to binge eat to compensate for this reward deficit, though the hypo-responsivity might be a result of a history of binge eating highly palatable foods. PMID:21997421

Neural representation of consciously imperceptible speech sound differences.

PubMed

Allen, J; Kraus, N; Bradlow, A

2000-10-01

The concept of subliminal perception has been a subject of interest and controversy for decades. Of interest in the present investigation was whether a neurophysiologic index of stimulus change could be elicited to speech sound contrasts that were consciously indiscriminable. The stimuli were chosen on the basis of each individual subject's discrimination threshold. The speech stimuli (which varied along an F3 onset frequency continuum from /da/ to /ga/) were synthesized so that the acoustical properties of the stimuli could be tightly controlled. Subthreshold and suprathreshold stimuli were chosen on the basis of behavioral ability demonstrated during psychophysical testing. A significant neural representation of stimulus change, reflected by the mismatch negativity response, was obtained in all but 1 subject in response to subthreshold stimuli. Grand average responses differed significantly from responses obtained in a control condition consisting of physiologic responses elicited by physically identical stimuli. Furthermore, responses to suprathreshold stimuli (close to threshold) did not differ significantly from subthreshold responses with respect to latency, amplitude, or area. These results suggest that neural representation of consciously imperceptible stimulus differences occurs and that this representation occurs at a preattentive level.

From Asperger's Autistischen Psychopathen to DSM-5 Autism Spectrum Disorder and Beyond: A Subthreshold Autism Spectrum Model

PubMed Central

Dell’Osso, Liliana; Luche, Riccardo Dalle; Gesi, Camilla; Moroni, Ilenia; Carmassi, Claudia; Maj, Mario

2016-01-01

Growing interest has recently been devoted to partial forms of autism, lying at the diagnostic boundaries of those conditions previously diagnosed as Asperger’s Disorder. This latter includes an important retrieval of the European classical psychopathological concepts of adult autism to which Hans Asperger referred in his work. Based on the review of Asperger's Autistische Psychopathie, from first descriptions through the DSM-IV Asperger’s Disorder and up to the recent DSM-5 Autism Spectrum Disorder, the paper aims to propose a Subthreshold Autism Spectrum Model that encompasses not only threshold-level manifestations but also mild/atypical symptoms, gender-specific features, behavioral manifestations and personality traits associated with Autism Spectrum Disorder. This model includes, but is not limited to, the so-called broad autism phenotype spanning across the general population that does not fully meet Autism Spectrum Disorder criteria. From this perspective, we propose a subthreshold autism as a unique psychological/behavioral model for research that could help to understand the neurodevelopmental trajectories leading from autistic traits to a broad range of mental disorders. PMID:27867417

Stochastic resonance on a modular neuronal network of small-world subnetworks with a subthreshold pacemaker

NASA Astrophysics Data System (ADS)

Yu, Haitao; Wang, Jiang; Liu, Chen; Deng, Bin; Wei, Xile

2011-12-01

We study the phenomenon of stochastic resonance on a modular neuronal network consisting of several small-world subnetworks with a subthreshold periodic pacemaker. Numerical results show that the correlation between the pacemaker frequency and the dynamical response of the network is resonantly dependent on the intensity of additive spatiotemporal noise. This effect of pacemaker-driven stochastic resonance of the system depends extensively on the local and the global network structure, such as the intra- and inter-coupling strengths, rewiring probability of individual small-world subnetwork, the number of links between different subnetworks, and the number of subnetworks. All these parameters play a key role in determining the ability of the network to enhance the noise-induced outreach of the localized subthreshold pacemaker, and only they bounded to a rather sharp interval of values warrant the emergence of the pronounced stochastic resonance phenomenon. Considering the rather important role of pacemakers in real-life, the presented results could have important implications for many biological processes that rely on an effective pacemaker for their proper functioning.

Neural Energy Supply-Consumption Properties Based on Hodgkin-Huxley Model

PubMed Central

2017-01-01

Electrical activity is the foundation of the neural system. Coding theories that describe neural electrical activity by the roles of action potential timing or frequency have been thoroughly studied. However, an alternative method to study coding questions is the energy method, which is more global and economical. In this study, we clearly defined and calculated neural energy supply and consumption based on the Hodgkin-Huxley model, during firing action potentials and subthreshold activities using ion-counting and power-integral model. Furthermore, we analyzed energy properties of each ion channel and found that, under the two circumstances, power synchronization of ion channels and energy utilization ratio have significant differences. This is particularly true of the energy utilization ratio, which can rise to above 100% during subthreshold activity, revealing an overdraft property of energy use. These findings demonstrate the distinct status of the energy properties during neuronal firings and subthreshold activities. Meanwhile, after introducing a synapse energy model, this research can be generalized to energy calculation of a neural network. This is potentially important for understanding the relationship between dynamical network activities and cognitive behaviors. PMID:28316842

[Eating disorders and depressive symptoms: an epidemiological study in a male population].

PubMed

Valls, M; Callahan, S; Rousseau, A; Chabrol, H

2014-06-01

The objective of the study was to evaluate the incidence of eating disorders, including not otherwise specified eating disorders (EDNOS) and subthreshold disorders, inappropriate compensatory behaviors (such as self-induced vomiting, strict dieting, fasting) along with depressive symptoms among young French adult males. The sample was composed of 458 young men in age ranging from 18 to 30 years (mean age=21.9±2.4). The average body mass index was 22.8±3. Participants completed two questionnaires: the Questionnaire for Eating Disorders Diagnoses (Q-EDD) assessing full-criteria eating disorder symptoms based on DSM-IV criteria (i.e. clinical eating disorders) and subthreshold disorders, and the Center for Epidemiological Studies-Depression scale (CES-D) assessing depressive symptoms. Out of the 458 surveyed respondents, eating disorders were reported by approximately 17% of the overall sample, with 1.5% meeting diagnostic criteria for serious clinical disorders, 3% meeting diagnostic criteria for EDNOS and 12% meeting diagnostic criteria for subthreshold disorders. Exercise bulimia represented 1% of the overall sample and binge-eating disorder 2%. The most frequent subthreshold disorder was subthreshold nonbinging bulimia (7%). Participants with eating disorders were equally divided between those desiring weight gain, those desiring weight loss and those wanting to keep their current weight. Participants without eating disorders were more likely to want to gain weight compared to participants with eating disorders (45.5% versus 30% respectively; P<0.05). After controlling for body mass index, 30% of participants tended to perceive themselves as thinner than they actually were and 6% tended to perceive themselves as fatter. Regarding normal-weight participants, 28% perceived themselves as thinner and 8% as fatter than in reality. Overeating episodes were reported by 19% of participants. Binge-eating episodes (recurrent or not) were reported by 8% of young men, including 32% of participants with eating disorders and 3% of participants without eating disorder. Six percent reported repeated binging (at least twice a week for at least once a month). Inappropriate compensatory behaviors were mostly used by participants with eating disorders, except for excessive exercise (34% versus 35% for participants without eating disorders). The most typical compensatory behavior was fasting (11%). According to the cut-off score of 22, 18% of young men had a moderate to severe depressive symptomatology, including 5% of participants who also reported an eating disorder (i.e. 30 participants). A one-way ANOVA was conducted to examine differences in depressive symptoms as a function of eating disorder groups, namely the clinical eating disorders sample (n=22), the subthreshold disorders sample (n=54) and the asymptomatic sample (participants without eating disorder; n=382). Results were statistically significant, (F(2,455)=7.27, P<0.001) and post-hoc tests (Scheffé tests) were used to examine the group differences. The mean CES-D scores for the clinical eating disorders sample (19.45±8.2; P<0.05) and the subthreshold disorders sample (18.15±10.9; P<0.05) were significantly higher than for the asymptomatic sample (14.19±8.9). There was no significant difference between the two eating disorder groups (P>0.05). The results demonstrate that a significant proportion of men with eating disorders manifest comorbid depressive symptomatology. These results suggest that EDNOS and subthreshold disorders should be taken into consideration, as they represent 15% of the total sample. Participants reported high rate of excessive exercise and fasting, which could reflect the importance of muscle tone or strategies to increase muscle mass. Further research is necessary in order to better understand male eating behaviors and disorders. Copyright © 2013 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Impact of scaling voltage and size on the performance of Side-contacted Field Effect Diode

NASA Astrophysics Data System (ADS)

Touchaei, Behnam Jafari; Manavizadeh, Negin

2018-05-01

Side-contacted Fild Effect Diode (S-FED), with low leakage current and high Ion/Ioff ratio, has been recently introduced to suppress short channel effects in nanoscale regime. The voltage and size scalability of S-FEDs and effects on the power consumption, propagation delay time, and power delay product have been studied in this article. The most attractive properties are related to channel length to channel thickness ratio in the S-FED which reduces in comparison with MOSFET significantly, while gates control over the channel improve and the off-state current reduces dramatically. This promising advantage is not only capable to improve important S-FED's characteristics such as subthreshold slope but also eliminate Latch-up and floating body effect.

A MODFET dc model with improved pinchoff and saturation characteristics

NASA Astrophysics Data System (ADS)

Rohdin, Hans; Roblin, Patrick

1986-05-01

An improved analytical dc model for the MODFET is proposed which uses a new approximation of the two-dimensional electron gas concentration versus gate-to-channel voltage, a ratio which models both the subthreshold region and the gradual saturation of carriers due to the onset of AlGaAs charge modulation. A two-region Grebene-Ghandi model with a floating boundary is used for the channel. A maximum transconductance and a finite intrinsic output conductance in the saturated region are predicted, in agreement with experimental observations. The model is shown to approach the saturated velocity model in the limit of very short gate lengths, and to approach the classical gradual channel model in the limit of very long gate lengths.

Silicon tunnel FET with average subthreshold slope of 55 mV/dec at low drain currents

NASA Astrophysics Data System (ADS)

Narimani, K.; Glass, S.; Bernardy, P.; von den Driesch, N.; Zhao, Q. T.; Mantl, S.

2018-05-01

In this paper we present a silicon tunnel FET based on line-tunneling to achieve better subthreshold performance. The fabricated device shows an on-current of Ion = 2.55 × 10-7 A/μm at Vds = Von = Vgs - Voff = -0.5 V for an Ioff = 1 nA/μm and an average SS of 55 mV/dec over two orders of magnitude of Id. Furthermore, the analog figures of merit have been calculated and show that the transconductance efficiency gm/Id beats the MOSFET performance at low currents.

Effect of organic buffer layer in the electrical properties of amorphous-indium gallium zinc oxide thin film transistor.

PubMed

Wang, Jian-Xun; Hyung, Gun Woo; Li, Zhao-Hui; Son, Sung-Yong; Kwon, Sang Jik; Kim, Young Kwan; Cho, Eou Sik

2012-07-01

In this research, we reported on the fabrication of top-contact amorphous-indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) with an organic buffer layer between inorganic gate dielectric and active layer in order to improve the electrical properties of devices. By inserting an organic buffer layer, it was possible to make an affirmation of the improvements in the electrical characteristics of a-IGZO TFTs such as subthreshold slope (SS), on/off current ratio (I(ON/OFF)), off-state current, and saturation field-effect mobility (muFE). The a-IGZO TFTs with the cross-linked polyvinyl alcohol (c-PVA) buffer layer exhibited the pronounced improvements of the muFE (17.4 cm2/Vs), SS (0.9 V/decade), and I(ON/OFF) (8.9 x 10(6)).

Subthreshold and micropulse diode laser photocoagulation.

PubMed

Dorin, Giorgio

2003-09-01

Retinal laser photocoagulation is a proven, effective treatment for various retinal disorders. Common clinical protocols use intra-operatively visible endpoints that cause iatrogenic chorioretinal damage. For this reason, laser therapy is normally limited to levels of disease severity for which the benefit-to-risk ratio justifies its application. The use of 810 nm diode lasers in the MicroPulse mode offers the surgeon the possibility to minimize iatrogenic retinal damage. A less destructive laser therapy with a more favorable benefit-to-risk ratio could justify treatment earlier in the course of the disease, allowing for stabilization or improvement of less compromised visual functions.

Exposure to subthreshold dose of UVR-B induces apoptosis in the lens epithelial cells and does not in the lens cortical fibre cells.

PubMed

Galichanin, Konstantin

2017-12-01

The aim of this study was to investigate in which part of the lens in vivo exposure to subthreshold dose of UVR-B radiation induces apoptosis. Twenty 6-week-old female albino Sprague-Dawley rats were exposed to subthreshold dose (1 kJ/m 2 ) of UVR-B unilaterally and killed at 120 hr after exposure. Lenses were enucleated and dissected on three regions: the lens epithelium, the cortex and the nucleus. The lens nucleus then was removed. Apoptosis markers p53 and caspase 3 were used to study apoptosis in the lens regions. qRT-PCR and Western blot were utilized to analyse the lenses. TP53 and CASP3 mRNA expressions are increased in exposed lenses, both in the lens epithelium and in the cortex regions, in relation to non-exposed lenses. Expression of p53 protein is increased in exposed lens epithelium in relation to non-exposed lens epithelium. Caspase 3 protein is expressed in exposed lens epithelial cells, while it is not expressed in non-exposed lens epithelial cells. p53 and caspase 3 proteins are not expressed in either exposed nor non-exposed lens fibre cells. Exposure to UVR-B increases mRNA transcription of apoptosis marker p53 in vivo in both regions of the lens and of apoptosis marker caspase 3 in the lens cortex. Exposure to UVR-B increases p53 and caspase 3 proteins expression just in the lens epithelium. In vivo exposure to subthreshold dose of UVR-B induces apoptosis in the lens epithelial cells and does not in the lens fibre cells. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Subthreshold resonances and resonances in the R -matrix method for binary reactions and in the Trojan horse method

NASA Astrophysics Data System (ADS)

Mukhamedzhanov, A. M.; Shubhchintak, Bertulani, C. A.

2017-08-01

In this paper we discuss the R -matrix approach to treat the subthreshold resonances for the single-level and one-channel and for the single-level and two-channel cases. In particular, the expression relating the asymptotic normalization coefficient (ANC) with the observable reduced width, when the subthreshold bound state is the only channel or coupled with an open channel, which is a resonance, is formulated. Since the ANC plays a very important role in nuclear astrophysics, these relations significantly enhance the power of the derived equations. We present the relationship between the resonance width and the ANC for the general case and consider two limiting cases: wide and narrow resonances. Different equations for the astrophysical S factors in the R -matrix approach are presented. After that we discuss the Trojan horse method (THM) formalism. The developed equations are obtained using the surface-integral formalism and the generalized R -matrix approach for the three-body resonant reactions. It is shown how the Trojan horse (TH) double-differential cross section can be expressed in terms of the on-the-energy-shell astrophysical S factor for the binary subreaction. Finally, we demonstrate how the THM can be used to calculate the astrophysical S factor for the neutron generator 13C(α ,n )16O in low-mass AGB stars. At astrophysically relevant energies this astrophysical S factor is controlled by the threshold level 1 /2+,Ex=6356 keV. Here, we reanalyzed recent TH data taking into account more accurately the three-body effects and using both assumptions that the threshold level is a subthreshold bound state or it is a resonance state.

Layer- and cell-type-specific subthreshold and suprathreshold effects of long-term monocular deprivation in rat visual cortex.

PubMed

Medini, Paolo

2011-11-23

Connectivity and dendritic properties are determinants of plasticity that are layer and cell-type specific in the neocortex. However, the impact of experience-dependent plasticity at the level of synaptic inputs and spike outputs remains unclear along vertical cortical microcircuits. Here I compared subthreshold and suprathreshold sensitivity to prolonged monocular deprivation (MD) in rat binocular visual cortex in layer 4 and layer 2/3 pyramids (4Ps and 2/3Ps) and in thick-tufted and nontufted layer 5 pyramids (5TPs and 5NPs), which innervate different extracortical targets. In normal rats, 5TPs and 2/3Ps are the most binocular in terms of synaptic inputs, and 5NPs are the least. Spike responses of all 5TPs were highly binocular, whereas those of 2/3Ps were dominated by either the contralateral or ipsilateral eye. MD dramatically shifted the ocular preference of 2/3Ps and 4Ps, mostly by depressing deprived-eye inputs. Plasticity was profoundly different in layer 5. The subthreshold ocular preference shift was sevenfold smaller in 5TPs because of smaller depression of deprived inputs combined with a generalized loss of responsiveness, and was undetectable in 5NPs. Despite their modest ocular dominance change, spike responses of 5TPs consistently lost their typically high binocularity during MD. The comparison of MD effects on 2/3Ps and 5TPs, the main affected output cells of vertical microcircuits, indicated that subthreshold plasticity is not uniquely determined by the initial degree of input binocularity. The data raise the question of whether 5TPs are driven solely by 2/3Ps during MD. The different suprathreshold plasticity of the two cell populations could underlie distinct functional deficits in amblyopia.

Mechanisms of Firing Patterns in Fast-Spiking Cortical Interneurons

PubMed Central

Golomb, David; Donner, Karnit; Shacham, Liron; Shlosberg, Dan; Amitai, Yael; Hansel, David

2007-01-01

Cortical fast-spiking (FS) interneurons display highly variable electrophysiological properties. Their spike responses to step currents occur almost immediately following the step onset or after a substantial delay, during which subthreshold oscillations are frequently observed. Their firing patterns include high-frequency tonic firing and rhythmic or irregular bursting (stuttering). What is the origin of this variability? In the present paper, we hypothesize that it emerges naturally if one assumes a continuous distribution of properties in a small set of active channels. To test this hypothesis, we construct a minimal, single-compartment conductance-based model of FS cells that includes transient Na+, delayed-rectifier K+, and slowly inactivating d-type K+ conductances. The model is analyzed using nonlinear dynamical system theory. For small Na+ window current, the neuron exhibits high-frequency tonic firing. At current threshold, the spike response is almost instantaneous for small d-current conductance, g d, and it is delayed for larger g d. As g d further increases, the neuron stutters. Noise substantially reduces the delay duration and induces subthreshold oscillations. In contrast, when the Na+ window current is large, the neuron always fires tonically. Near threshold, the firing rates are low, and the delay to firing is only weakly sensitive to noise; subthreshold oscillations are not observed. We propose that the variability in the response of cortical FS neurons is a consequence of heterogeneities in their g d and in the strength of their Na+ window current. We predict the existence of two types of firing patterns in FS neurons, differing in the sensitivity of the delay duration to noise, in the minimal firing rate of the tonic discharge, and in the existence of subthreshold oscillations. We report experimental results from intracellular recordings supporting this prediction. PMID:17696606

Mechanisms of firing patterns in fast-spiking cortical interneurons.

PubMed

Golomb, David; Donner, Karnit; Shacham, Liron; Shlosberg, Dan; Amitai, Yael; Hansel, David

2007-08-01

Cortical fast-spiking (FS) interneurons display highly variable electrophysiological properties. Their spike responses to step currents occur almost immediately following the step onset or after a substantial delay, during which subthreshold oscillations are frequently observed. Their firing patterns include high-frequency tonic firing and rhythmic or irregular bursting (stuttering). What is the origin of this variability? In the present paper, we hypothesize that it emerges naturally if one assumes a continuous distribution of properties in a small set of active channels. To test this hypothesis, we construct a minimal, single-compartment conductance-based model of FS cells that includes transient Na(+), delayed-rectifier K(+), and slowly inactivating d-type K(+) conductances. The model is analyzed using nonlinear dynamical system theory. For small Na(+) window current, the neuron exhibits high-frequency tonic firing. At current threshold, the spike response is almost instantaneous for small d-current conductance, gd, and it is delayed for larger gd. As gd further increases, the neuron stutters. Noise substantially reduces the delay duration and induces subthreshold oscillations. In contrast, when the Na(+) window current is large, the neuron always fires tonically. Near threshold, the firing rates are low, and the delay to firing is only weakly sensitive to noise; subthreshold oscillations are not observed. We propose that the variability in the response of cortical FS neurons is a consequence of heterogeneities in their gd and in the strength of their Na(+) window current. We predict the existence of two types of firing patterns in FS neurons, differing in the sensitivity of the delay duration to noise, in the minimal firing rate of the tonic discharge, and in the existence of subthreshold oscillations. We report experimental results from intracellular recordings supporting this prediction.

Re-examining the risk for switch from unipolar to bipolar major depressive disorder in youth with ADHD: a long term prospective longitudinal controlled study.

PubMed

Biederman, Joseph; Wozniak, Janet; Tarko, Laura; Serra, Giulia; Hernandez, Mariely; McDermott, Katie; Woodsworth, K Yvonne; Uchida, Mai; Faraone, Stephen V

2014-01-01

Recent studies have identified subthreshold forms of bipolar (BP)-I disorder and deficits in emotional regulation as risk factors for bipolar disorder in youth. The primary aim of this study was to investigate whether emotional dysregulation and subthreshold forms of BP-I disorder increase the risk for BP switches in ADHD youth with non-bipolar MDD. We used data from two large controlled longitudinal family studies of boys and girls with and without ADHD. Subjects (N=522) were followed prospectively and blindly over an average follow up period of 11.4 years. Comparisons were made between ADHD youth with unipolar major depression (MDD) who did (N=24) and did not (N=79) switch to BP-I disorder at follow-up. The rate of conversion to BP-I disorder at follow up was higher in MDD subjects with subthreshold BP-I disorder at baseline compared to those without (57% vs. 21%; OR=9.57, 95% CI=1.62-56.56, p=0.013) and in MDD subjects with deficient emotional self-regulation (OR=3.54, 95% CI=1.08-11.60, p=0.037). The sample was largely Caucasian, so these results may not generalize to minority groups. The sample of youth with SED was small, which limited the statistical power for some analyses. Switches from unipolar MDD to BP-I disorder in children with ADHD and MDD were predicted by baseline subthreshold BP-I disorder symptoms and baseline deficits in emotional regulation. More work is needed to assess whether these risk factors are operant outside the context of ADHD. © 2013 Published by Elsevier B.V.

Controlled progressive innate immune stimulation regimen prevents the induction of sickness behavior in the open field test

PubMed Central

Chen, Qun; Tarr, Andrew J; Liu, Xiaoyu; Wang, Yufen; Reed, Nathaniel S; DeMarsh, Cameron P; Sheridan, John F; Quan, Ning

2013-01-01

Peripheral immune activation by bacterial mimics or live replicating pathogens is well known to induce central nervous system activation. Sickness behavior alterations are often associated with inflammation-induced increases in peripheral proinflammatory cytokines (eg, interleukin [IL]-1β and IL-6). However, most researchers have used acute high dose endotoxin/bacterial challenges to observe these outcomes. Using this methodology may pose inherent risks in the translational interpretation of the experimental data in these studies. Studies using Escherichia coli have yet to establish the full kinetics of repeated E. coli peripheral injections. Therefore, we sought to examine the effects of repeated low dose E. coli on sickness behavior and local peripheral inflammation in the open field test. Results from the current experiments showed a behavioral dose response, where increased amounts of E. coli resulted in correspondingly increased sickness behavior. Furthermore, animals that received a subthreshold dose (ie, one that did not cause sickness behavior) of E. coli 24 hours prior were able to withstand a larger dose of E. coli on the second day (a dose that would normally cause sickness behavior in mice without prior exposure) without inducing sickness behavior. In addition, animals that received escalating subthreshold doses of E. coli on days 1 and 2 behaviorally tolerated a dose of E. coli 25 times higher than what would normally cause sickness behavior if given acutely. Lastly, increased levels of E. coli caused increased IL-6 and IL-1β protein expression in the peritoneal cavity, and this increase was blocked by administering a subthreshold dose of E. coli 24 hours prior. These data show that progressive challenges with subthreshold levels of E. coli may obviate the induction of sickness behavior and proinflammatory cytokine expression. PMID:23950656

Controlled progressive innate immune stimulation regimen prevents the induction of sickness behavior in the open field test.

PubMed

Chen, Qun; Tarr, Andrew J; Liu, Xiaoyu; Wang, Yufen; Reed, Nathaniel S; Demarsh, Cameron P; Sheridan, John F; Quan, Ning

2013-01-01

Peripheral immune activation by bacterial mimics or live replicating pathogens is well known to induce central nervous system activation. Sickness behavior alterations are often associated with inflammation-induced increases in peripheral proinflammatory cytokines (eg, interleukin [IL]-1β and IL-6). However, most researchers have used acute high dose endotoxin/bacterial challenges to observe these outcomes. Using this methodology may pose inherent risks in the translational interpretation of the experimental data in these studies. Studies using Escherichia coli have yet to establish the full kinetics of repeated E. coli peripheral injections. Therefore, we sought to examine the effects of repeated low dose E. coli on sickness behavior and local peripheral inflammation in the open field test. Results from the current experiments showed a behavioral dose response, where increased amounts of E. coli resulted in correspondingly increased sickness behavior. Furthermore, animals that received a subthreshold dose (ie, one that did not cause sickness behavior) of E. coli 24 hours prior were able to withstand a larger dose of E. coli on the second day (a dose that would normally cause sickness behavior in mice without prior exposure) without inducing sickness behavior. In addition, animals that received escalating subthreshold doses of E. coli on days 1 and 2 behaviorally tolerated a dose of E. coli 25 times higher than what would normally cause sickness behavior if given acutely. Lastly, increased levels of E. coli caused increased IL-6 and IL-1β protein expression in the peritoneal cavity, and this increase was blocked by administering a subthreshold dose of E. coli 24 hours prior. These data show that progressive challenges with subthreshold levels of E. coli may obviate the induction of sickness behavior and proinflammatory cytokine expression.

Co-occurrence of attention-deficit hyperactivity disorder symptoms with other psychopathology in young adults: parenting style as a moderator.

PubMed

Ni, Hsing-Chang; Gau, Susan Shur-Fen

2015-02-01

The extent to which parenting styles can influence secondary psychiatric symptoms among young adults with ADHD symptoms is unknown. This issue was investigated in a sample of 2284 incoming college students (male, 50.6%), who completed standardized questionnaires about adult ADHD symptoms, other DSM-IV symptoms, and their parents' parenting styles before their ages of 16. Among them, 2.8% and 22.8% were classified as having ADHD symptoms and sub-threshold ADHD symptoms, respectively. Logistic regression was used to compare the comorbid rates of psychiatric symptoms among the ADHD, sub-threshold ADHD and non-ADHD groups while multiple linear regressions were used to examine the moderating role of gender and parenting styles over the associations between ADHD and other psychiatric symptoms. Both ADHD groups were significantly more likely than other incoming students to have other DSM-IV symptoms. Parental care was negatively associated and parental overprotection/control positively associated with these psychiatric symptoms. Furthermore, significant interactions were found of parenting style with both threshold and sub-threshold ADHD in predicting wide-ranging comorbid symptoms. Specifically, the associations of ADHD with some externalizing symptoms were inversely related to level of paternal care, while associations of ADHD and sub-threshold ADHD with wide-ranging comorbid symptoms were positively related to level of maternal and paternal overprotection/control. These results suggest that parenting styles may modify the effects of ADHD on the risk of a wide range of temporally secondary DSM-IV symptoms among incoming college students, although other causal dynamics might be at work that need to be investigated in longitudinal studies. Copyright © 2014 Elsevier Inc. All rights reserved.

Enthusiasm for homework and improvement of psychological distress in subthreshold depression during behavior therapy: secondary analysis of data from a randomized controlled trial.

PubMed

Hayasaka, Y; Furukawa, T A; Sozu, T; Imai, H; Kawakami, N; Horikoshi, M

2015-11-25

Cognitive behavioral therapy (CBT) usually involves homework, the completion of which is a known predictor of a positive outcome. The aim of the present study was to examine the session-by-session relationships between enthusiasm to complete the homework and the improvement of psychological distress in depressed people through the course of therapy. Working people with subthreshold depression were recruited to participate in the telephone CBT (tCBT) program with demonstrated effectiveness. Their enthusiasm for homework was enhanced with motivational interviewing techniques and was measured by asking two questions: "How strongly do you feel you want to do this homework?" and "How confident do you feel you can actually accomplish this homework?" at the end of each session. The outcome was the K6 score, which was administered at the start of each session. The K6 is an index of psychological distress including depression and anxiety. We used structural equation modeling (SEM) to elucidate the relationships between enthusiasm and the K6 scores from session to session. The best fitting model suggested that, throughout the course of behavior therapy (BT), enthusiasm to complete the homework was negatively correlated with the K6 scores for the subsequent session, while the K6 score measured at the beginning of the session did not influence the enthusiasm to complete the homeworks assigned for that session. Empirical data now support the practitioners of BT when they try to enhance their patient's enthusiasm for homework regardless of the participant's distress, which then would lead to a reduction in distress in the subsequent week. ClinicalTrials.gov NCT00885014 . April 20, 2009.

Microstructure and conductance-slope of InAs/GaSb tunnel diodes

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

Iutzi, Ryan M., E-mail: iutzi@mit.edu; Fitzgerald, Eugene A.

2014-06-21

InAs/GaSb and similar materials systems have generated great interest as a heterojunction for tunnel field effect transistors (TFETs) due to favorable band alignment. However, little is currently understood about how such TFETs are affected by materials defects and nonidealities. We present measurements of the conductance slope for various InAs/GaSb heterojunctions via two-terminal electrical measurements, which removes three-terminal parasitics and enables direct study on the effect of microstructure on tunnelling. Using this, we can predict how subthreshold swings in TFETs can depend on microstructure. We also demonstrate growth and electrical characterization for structures grown by metalorganic chemical vapor deposition (MOCVD)—a generallymore » more scalable process compared with molecular beam epitaxy (MBE). We determine that misfit dislocations and point defects near the interface can lead to energy states in the band-gap and local band bending that result in trap-assisted leakage routes and nonuniform band alignment across the junction area that lower the steepness of the conductance slope. Despite the small lattice mismatch, misfit dislocations still form in InAs on GaSb due to relaxation as a result of large strain from intermixed compositions. This can be circumvented by growing GaSb on InAs, straining the GaSb underlayer, or lowering the InAs growth temperature in the region of the interface. The conductance slope can also be improved by annealing the samples at higher temperatures, which we believe acts to annihilate point defects and average out major fluctuations in band alignment across the interface. Using a combination of these techniques, we can greatly improve the steepness of the conductance slope which could result in steeper subthreshold swings in TFETs in the future.« less

The first science result with the JENSA gas-jet target: Confirmation and study of a strong subthreshold F 18 ( p , α ) O 15 resonance

DOE PAGES

Bardayan, D. W.; Chipps, K. A.; Ahn, S.; ...

2015-11-28

The astrophysical 18F( p,α) 15O rate determines, in large part, the extent to which the observable radioisotope 18F is produced in novae. This rate, however, has been extremely uncertain owing to the unknown properties of a strong subthreshold resonance and its possible interference with higher-lying resonances. In addition, the new Jet Experiments in Nuclear Structure and Astrophysics (JENSA) gas-jet target has been used for the first time to determine the spin of this important resonance and significantly reduce uncertainties in the 18F( p,α) 15O rate.

Influence of trap-assisted tunneling on trap-assisted tunneling current in double gate tunnel field-effect transistor

NASA Astrophysics Data System (ADS)

Zhi, Jiang; Yi-Qi, Zhuang; Cong, Li; Ping, Wang; Yu-Qi, Liu

2016-02-01

Trap-assisted tunneling (TAT) has attracted more and more attention, because it seriously affects the sub-threshold characteristic of tunnel field-effect transistor (TFET). In this paper, we assess subthreshold performance of double gate TFET (DG-TFET) through a band-to-band tunneling (BTBT) model, including phonon-assisted scattering and acoustic surface phonons scattering. Interface state density profile (Dit) and the trap level are included in the simulation to analyze their effects on TAT current and the mechanism of gate leakage current. Project supported by the National Natural Science Foundation of China (Grant Nos. 61574109 and 61204092).

The first science result with the JENSA gas-jet target: Confirmation and study of a strong subthreshold F 18 ( p , α ) O 15 resonance

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

Bardayan, D. W.; Chipps, K. A.; Ahn, S.

The astrophysical 18F( p,α) 15O rate determines, in large part, the extent to which the observable radioisotope 18F is produced in novae. This rate, however, has been extremely uncertain owing to the unknown properties of a strong subthreshold resonance and its possible interference with higher-lying resonances. In addition, the new Jet Experiments in Nuclear Structure and Astrophysics (JENSA) gas-jet target has been used for the first time to determine the spin of this important resonance and significantly reduce uncertainties in the 18F( p,α) 15O rate.

Analytical model of nanoscale junctionless transistors towards controlling of short channel effects through source/drain underlap and channel thickness engineering

NASA Astrophysics Data System (ADS)

Roy, Debapriya; Biswas, Abhijit

2018-01-01

We develop a 2D analytical subthreshold model for nanoscale double-gate junctionless transistors (DGJLTs) with gate-source/drain underlap. The model is validated using well-calibrated TCAD simulation deck obtained by comparing experimental data in the literature. To analyze and control short-channel effects, we calculate the threshold voltage, drain induced barrier lowering (DIBL) and subthreshold swing of DGJLTs using our model and compare them with corresponding simulation value at channel length of 20 nm with channel thickness tSi ranging 5-10 nm, gate-source/drain underlap (LSD) values 0-7 nm and source/drain doping concentrations (NSD) ranging 5-12 × 1018 cm-3. As tSi reduces from 10 to 5 nm DIBL drops down from 42.5 to 0.42 mV/V at NSD = 1019 cm-3 and LSD = 5 nm in contrast to decrement from 71 to 4.57 mV/V without underlap. For a lower tSiDIBL increases marginally with increasing NSD. The subthreshold swing reduces more rapidly with thinning of channel thickness rather than increasing LSD or decreasing NSD.

Polysubstance and Behavioral Addictions in a Patient with Bipolar Disorder: Role of Lifetime Subthreshold Autism Spectrum

PubMed Central

Dell'Osso, Liliana; Conversano, Ciro; Bertelloni, Carlo A.; Cremone, Ivan M.; Carpita, Barbara; Gesi, Camilla

2018-01-01

This case report draws attention to the potential relevance of undetected autism spectrum symptoms in a bipolar patient with high work functioning showing a peculiar addictive profile with impulsive and antisocial behaviors. A 23-year-old man with a diagnosis of Bipolar Disorder (BD) and Substance Use Disorder (SUD) was hospitalized at the Psychiatric Clinic of the University of Pisa for diuretics and β-2 adrenergic agonist abuse in a remission phase of benzodiazepines and substance abuse. He reported a history of behavioral addictions in the framework of a global high work functioning with particular skills in computer science. When assessed for adult autism spectrum symptoms, despite not fulfilling a DSM-5 diagnosis of Autism Spectrum Disorder (ASD), he reported a score of 93/240 at the Ritvo Autism and Asperger Diagnostic Scale (RAADS-r) and of 88/160 at the Adult Autism Subthreshold Spectrum (AdAS Spectrum), both indicative of ASD. We argue the possible role of adult subthreshold autism spectrum features, generally disregarded in adult psychiatry, in the peculiar addictive profile developed by this patient with BD that may deserve appropriate treatment. PMID:29682383

Effect of endothelin-1 on the serotonin-induced contraction of smooth muscle in the guinea pig trachea.

PubMed

Yoshida, M; Aizawa, H; Hara, N

1999-01-01

Endothelin (ET), a potent constrictor of smooth muscle including that of the airways, may contribute to the development of airway hyperresponsiveness. To investigate the role of ET-1 on the airway smooth muscle, we examined the effects of ET-1 on the serotonin-induced contraction of guinea pig tracheal smooth muscle. The changes in isometric tension evoked by serotonin were measured before and after the application of a subthreshold dose (a dose which did not induce smooth muscle contraction by itself) of ET-1. Serotonin caused smooth muscle contraction in a dose-dependent manner. The subthreshold doses of ET-1 (1 pM) and sarafotoxin 6c (1 pM), a selective ETB receptor agonist, were found to potentiate significantly the contraction induced by serotonin. A potentiating effect of ET-1 was not altered by indomethacin or calphostin C, a protein kinase C inhibitor. These results suggest that a subthreshold concentration of ET-1 can potentiate serotonin-induced contraction of smooth muscle through the activation of ETB receptor, while in contrast cyclooxygenase and protein kinase C were found not to be involved in this mechanism.

Field-effect transistors as electrically controllable nonlinear rectifiers for the characterization of terahertz pulses

NASA Astrophysics Data System (ADS)

Lisauskas, Alvydas; Ikamas, Kestutis; Massabeau, Sylvain; Bauer, Maris; ČibiraitÄ--, DovilÄ--; Matukas, Jonas; Mangeney, Juliette; Mittendorff, Martin; Winnerl, Stephan; Krozer, Viktor; Roskos, Hartmut G.

2018-05-01

We propose to exploit rectification in field-effect transistors as an electrically controllable higher-order nonlinear phenomenon for the convenient monitoring of the temporal characteristics of THz pulses, for example, by autocorrelation measurements. This option arises because of the existence of a gate-bias-controlled super-linear response at sub-threshold operation conditions when the devices are subjected to THz radiation. We present measurements for different antenna-coupled transistor-based THz detectors (TeraFETs) employing (i) AlGaN/GaN high-electron-mobility and (ii) silicon CMOS field-effect transistors and show that the super-linear behavior in the sub-threshold bias regime is a universal phenomenon to be expected if the amplitude of the high-frequency voltage oscillations exceeds the thermal voltage. The effect is also employed as a tool for the direct determination of the speed of the intrinsic TeraFET response which allows us to avoid limitations set by the read-out circuitry. In particular, we show that the build-up time of the intrinsic rectification signal of a patch-antenna-coupled CMOS detector changes from 20 ps in the deep sub-threshold voltage regime to below 12 ps in the vicinity of the threshold voltage.

Cost-effectiveness of a stepped-care intervention to prevent major depression in patients with type 2 diabetes mellitus and/or coronary heart disease and subthreshold depression: design of a cluster-randomized controlled trial.

PubMed

van Dijk, Susan E M; Pols, Alide D; Adriaanse, Marcel C; Bosmans, Judith E; Elders, Petra J M; van Marwijk, Harm W J; van Tulder, Maurits W

2013-05-07

Co-morbid major depression is a significant problem among patients with type 2 diabetes mellitus and/or coronary heart disease and this negatively impacts quality of life. Subthreshold depression is the most important risk factor for the development of major depression. Given the highly significant association between depression and adverse health outcomes and the limited capacity for depression treatment in primary care, there is an urgent need for interventions that successfully prevent the transition from subthreshold depression into a major depressive disorder. Nurse led stepped-care is a promising way to accomplish this. The aim of this study is to evaluate the cost-effectiveness of a nurse-led indicated stepped-care program to prevent major depression among patients with type 2 diabetes mellitus and/or coronary heart disease in primary care who also have subthreshold depressive symptoms. An economic evaluation will be conducted alongside a cluster-randomized controlled trial in approximately thirty general practices in the Netherlands. Randomization takes place at the level of participating practice nurses. We aim to include 236 participants who will either receive a nurse-led indicated stepped-care program for depressive symptoms or care as usual. The stepped-care program consists of four sequential but flexible treatment steps: 1) watchful waiting, 2) guided self-help treatment, 3) problem solving treatment and 4) referral to the general practitioner. The primary clinical outcome measure is the cumulative incidence of major depressive disorder as measured with the Mini International Neuropsychiatric Interview. Secondary outcomes include severity of depressive symptoms, quality of life, anxiety and physical outcomes. Costs will be measured from a societal perspective and include health care utilization, medication and lost productivity costs. Measurements will be performed at baseline and 3, 6, 9 and 12 months. The intervention being investigated is expected to prevent new cases of depression among people with type 2 diabetes mellitus and/or coronary heart disease and subthreshold depression, with subsequent beneficial effects on quality of life, clinical outcomes and health care costs. When proven cost-effective, the program provides a viable treatment option in the Dutch primary care system. Dutch Trial Register NTR3715.

Nanowire Tunnel Field Effect Transistors: Prospects and Pitfalls

NASA Astrophysics Data System (ADS)

Sylvia, Somaia Sarwat

The tunnel field effect transistor (TFET) has the potential to operate at lower voltages and lower power than the field effect transistor (FET). The TFET can circumvent the fundamental thermal limit of the inverse subthreshold slope (S) by exploiting interband tunneling of non-equilibrium "cold" carriers. The conduction mechanism in the TFET is governed by band-to-band tunneling which limits the drive current. TFETs built with III-V materials like InAs and InSb can produce enough tunneling current because of their small direct bandgap. Our simulation results show that although they require highly degenerate source doping to support the high electric fields in the tunnel region, the devices achieve minimum inverse subthreshold slopes of 30 mV/dec. In subthreshold, these devices experience both regimes of voltage-controlled tunneling and cold-carrier injection. Numerical results based on a discretized 8-band k.p model are compared to analytical WKB theory. For both regular FETs and TFETs, direct channel tunneling dominates the leakage current when the physical gate length is reduced to 5 nm. Therefore, a survey of materials is performed to determine their ability to suppress the direct tunnel current through a 5 nm barrier. The tunneling effective mass gives the best indication of the relative size of the tunnel currents. Si gives the lowest overall tunnel current for both the conduction and valence band and, therefore, it is the optimum choice for suppressing tunnel current at the 5 nm scale. Our numerical simulation shows that the finite number, random placement, and discrete nature of the dopants in the source of an InAs nanowire (NW) TFET affect both the mean value and the variance of the drive current and the inverse subthreshold slope. The discrete doping model gives an average drive current and an inverse subthreshold slope that are less than those predicted from the homogeneous doping model. The doping density required to achieve a target drive current is higher in the discrete doping model compared to the homogeneous doping model. The relative variation in the ON current decreases as the average doping density and/or NW diameter increases. For the largest 8 nm NW studied, the coefficient of variation in the ON current is ˜15% at a doping density of 1.5 x 1020 cm--3. Results from full self-consistent non-equilibrium Green's function calculations and semi-classical calculations are compared.

Hysteresis-Free Carbon Nanotube Field-Effect Transistors.

PubMed

Park, Rebecca S; Hills, Gage; Sohn, Joon; Mitra, Subhasish; Shulaker, Max M; Wong, H-S Philip

2017-05-23

While carbon nanotube (CNT) field-effect transistors (CNFETs) promise high-performance and energy-efficient digital systems, large hysteresis degrades these potential CNFET benefits. As hysteresis is caused by traps surrounding the CNTs, previous works have shown that clean interfaces that are free of traps are important to minimize hysteresis. Our previous findings on the sources and physics of hysteresis in CNFETs enabled us to understand the influence of gate dielectric scaling on hysteresis. To begin with, we validate through simulations how scaling the gate dielectric thickness results in greater-than-expected benefits in reducing hysteresis. Leveraging this insight, we experimentally demonstrate reducing hysteresis to <0.5% of the gate-source voltage sweep range using a very large-scale integration compatible and solid-state technology, simply by fabricating CNFETs with a thin effective oxide thickness of 1.6 nm. However, even with negligible hysteresis, large subthreshold swing is still observed in the CNFETs with multiple CNTs per transistor. We show that the cause of large subthreshold swing is due to threshold voltage variation between individual CNTs. We also show that the source of this threshold voltage variation is not explained solely by variations in CNT diameters (as is often ascribed). Rather, other factors unrelated to the CNTs themselves (i.e., process variations, random fixed charges at interfaces) are a significant factor in CNT threshold voltage variations and thus need to be further improved.

Thinking dimensional: prevalence of DSM-5 early adolescent full syndrome, partial and subthreshold eating disorders in a cross-sectional survey in German schools.

PubMed

Hammerle, Florian; Huss, Michael; Ernst, Verena; Bürger, Arne

2016-05-05

Investigating for the first time in Germany Diagnostic and Statistical Manual Fifth Edition (DSM-5) prevalences of adolescent full syndrome, Other Specified Feeding or Eating Disorder (OSFED), partial and subthreshold anorexia nervosa (AN), bulimia nervosa (BN) and binge eating disorder (BED). A national school-based cross-sectional survey with nine schools in Germany was undertaken that was aimed at students from grades 7 and 8. Of the 1775 students who were contacted to participate in the study, 1654 participated (participation rate: 93.2%). The sample consisted of 873 female and 781 male adolescents (mean age=13.4 years). Prevalence rates were established using direct symptom criteria with a structured inventory (SIAB-S) and an additional self-report questionnaire (Eating Disorder Inventory 2 (EDI-2)). Prevalences for full syndrome were 0.3% for AN, 0.4% for BN, 0.5% for BED and 3.6% for OSFED-atypical AN, 0% for BN (low frequency/limited duration), 0% for BED (low frequency/limited duration) and 1.9% for purging disorder (PD). Prevalences of partial syndrome were 10.9% for AN (7.1% established with cognitive symptoms only, excluding weight criteria), 0.2% for BN and 2.1% for BED, and of subthreshold syndrome were 0.8% for AN, 0.3% for BN and 0.2% for BED. Cases on EDI-2 scales were much more pronounced with 12.6-21.1% of the participants with significant sex differences. The findings were in accordance with corresponding international studies but were in contrast to other German studies showing much higher prevalence rates. The study provides, for the first time, estimates for DSM-5 prevalences of eating disorders in adolescents for Germany, and evidence in favour of using valid measures for improving prevalence estimates. DRKS00005050; Results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Older people, the natural environment and common mental disorders: cross-sectional results from the Cognitive Function and Ageing Study.

PubMed

Wu, Yu-Tzu; Prina, A Matthew; Jones, Andy; Matthews, Fiona E; Brayne, Carol

2015-09-16

To explore the hypothesis that higher exposure to natural environments in local areas is associated with a lower odds of depression and anxiety in later life. A cross-sectional study based on the year-10 interview of the Medical Research Council Cognitive Function and Ageing Study (CFAS), a population-based study of ageing in the UK. Postcodes of the CFAS participants were mapped onto small geographic units, lower-layer super output areas (LSOAs) and linked to environmental data from government databases. The natural environment was characterised as the percentage of green space and private gardens in each LSOA based on the UK Generalised Land Use 2001 Dataset. 2424 people aged 74 and over in the CFAS year-10 follow-up interview (2001) from 4 English centres (Cambridgeshire, Nottingham, Newcastle and Oxford). Depression and anxiety; clinical and subthreshold cases were identified using the Geriatric Mental State Examination (GMS) package and its associated diagnostic algorithm: the Automated Geriatric Examination for Computer Assisted Taxonomy. Compared with the lowest quartile, living in the highest quartile of neighbourhood natural environment provision was associated with a reduced odds of subthreshold depression (OR 0.66, 95% CI 0.46 to 0.95), anxiety symptoms (OR 0.62, 95% CI 0.46 to 0.83) and their co-occurrence (OR 0.55, 95% CI 0.35 to 0.84) after adjusting for individual-level factors. Controlling for area deprivation attenuated the strength of associations for subthreshold depression by 20% but not for anxiety symptoms or for co-occurrence of the conditions. A high exposure to natural environments (green space and gardens) in communities was associated with fewer mental disorders among older people. Increasing provision of green environments in local areas could be a potential population-level intervention to improve mental health among older people. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Facile fabrication of high-performance InGaZnO thin film transistor using hydrogen ion irradiation at room temperature

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

Ahn, Byung Du; Park, Jin-Seong; Chung, K. B., E-mail: kbchung@dongguk.edu

Device performance of InGaZnO (IGZO) thin film transistors (TFTs) are investigated as a function of hydrogen ion irradiation dose at room temperature. Field effect mobility is enhanced, and subthreshold gate swing is improved with the increase of hydrogen ion irradiation dose, and there is no thermal annealing. The electrical device performance is correlated with the electronic structure of IGZO films, such as chemical bonding states, features of the conduction band, and band edge states below the conduction band. The decrease of oxygen deficient bonding and the changes in electronic structure of the conduction band leads to the improvement of devicemore » performance in IGZO TFT with an increase of the hydrogen ion irradiation dose.« less

Metal-induced crystallization of amorphous zinc tin oxide semiconductors for high mobility thin-film transistors

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

Hwang, Ah Young; Ji, Hyuk; Kim, Sang Tae

2016-04-11

Transition tantalum induced crystallization of amorphous zinc tin oxide (a-ZTO) was observed at low temperature annealing of 300 °C. Thin-film transistors (TFTs) with an a-ZTO channel layer exhibited a reasonable field-effect mobility of 12.4 cm{sup 2}/V s, subthreshold swing (SS) of 0.39 V/decade, threshold voltage (V{sub TH}) of 1.5 V, and I{sub ON/OFF} ratio of ∼10{sup 7}. A significant improvement in the field-effect mobility (up to ∼33.5 cm{sup 2}/V s) was achieved for crystallized ZTO TFTs: this improvement was accomplished without compromising the SS, V{sub TH}, or I{sub ON/OFF} ratio due to the presence of a highly ordered microstructure.

Comparison of obese and nonobese individuals with binge eating disorder: delicate boundary between binge eating disorder and non-purging bulimia nervosa.

PubMed

Carrard, Isabelle; Van der Linden, Martial; Golay, Alain

2012-09-01

To compare obese and nonobese individuals with binge eating disorder (BED) on demographic data, illness history, eating disorders and psychological health. This study used baseline data from a randomized controlled study on the efficacy of an online cognitive behavioural self-help treatment. Seventy-four women aged between 18 and 60 years were recruited in the community. They had to meet full or subthreshold diagnostic criteria for BED according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Forty per cent of the sample had a body mass index higher than 30 kg/m(2) . Mean age and severity of eating disorders were similar between obese and nonobese individuals. A statistically significant difference emerged regarding dietary restraint, with nonobese BED individuals exhibiting higher scores than obese BED individuals. Dietary restraint might be one of the factors explaining body mass index differences among BED individuals. This raises the question of the boundary between non-purging bulimia nervosa and BED in nonobese people. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.

Partial androgen deficiency, depression and testosterone treatment in aging men.

PubMed

Amore, Mario; Scarlatti, Fabiano; Quarta, Antonio Lucio; Tagariello, Pietro

2009-02-01

This study provides a critical review of the literature on depressive symptoms of partial androgen deficiency (PADAM) and their treatment with Testosterone (T). PADAM in aging males is responsible for a variety of behavioral symptoms, such as weakness, decreased libido and erectile dysfunction, lower psychological vitality, depressive mood, anxiety, insomnia, difficulty in concentrating, and memory impairment. The psychological and behavioural aspects of PADAM may overlap with signs and symptoms of major depression. Evidence of the relationship between androgen deficiency and male depression comes from studies that have assessed depression in hypogonadal subjects, the association between low T level and male depressive illness, and the antidepressant action of androgen replacement. The etiology of depressive symptoms of PADAM is multifactorial, and results from the interaction of the biological and psychosocial changes that take place during the mid-life transition. Although data derived from androgen treatment trials and androgen replacement do not support T treatment or replacement as more efficacious than placebo for major depressive disorder (MDD), the clinical impression is that, in some sub-threshold depressive syndromes, T may lead to antidepressant benefits.

Integrated digital inverters based on two-dimensional anisotropic ReS2 field-effect transistors

PubMed Central

Liu, Erfu; Fu, Yajun; Wang, Yaojia; Feng, Yanqing; Liu, Huimei; Wan, Xiangang; Zhou, Wei; Wang, Baigeng; Shao, Lubin; Ho, Ching-Hwa; Huang, Ying-Sheng; Cao, Zhengyi; Wang, Laiguo; Li, Aidong; Zeng, Junwen; Song, Fengqi; Wang, Xinran; Shi, Yi; Yuan, Hongtao; Hwang, Harold Y.; Cui, Yi; Miao, Feng; Xing, Dingyu

2015-01-01

Semiconducting two-dimensional transition metal dichalcogenides are emerging as top candidates for post-silicon electronics. While most of them exhibit isotropic behaviour, lowering the lattice symmetry could induce anisotropic properties, which are both scientifically interesting and potentially useful. Here we present atomically thin rhenium disulfide (ReS2) flakes with unique distorted 1T structure, which exhibit in-plane anisotropic properties. We fabricated monolayer and few-layer ReS2 field-effect transistors, which exhibit competitive performance with large current on/off ratios (∼107) and low subthreshold swings (100 mV per decade). The observed anisotropic ratio along two principle axes reaches 3.1, which is the highest among all known two-dimensional semiconducting materials. Furthermore, we successfully demonstrated an integrated digital inverter with good performance by utilizing two ReS2 anisotropic field-effect transistors, suggesting the promising implementation of large-scale two-dimensional logic circuits. Our results underscore the unique properties of two-dimensional semiconducting materials with low crystal symmetry for future electronic applications. PMID:25947630

The improvement of retention time of metal-ferroelectric (PbZr0.53Ti0.47O3)-insulator (ZrO2)-semiconductor transistors and capacitors by leakage current reduction using surface treatment

NASA Astrophysics Data System (ADS)

Shih, Wen-Chieh; Kang, Kun-Yung; Lee, Joseph Ya-Min

2007-11-01

Metal-ferroelectric-insulator-semiconductor transistors (MFISFETs) and capacitors with the structure of Al /Pb (Zr0.53,Ti0.47) O3/ZrO2/Si were fabricated. The wafers were pretreated with H2O2 before ZrO2 deposition and/or post-treated with HCl after ZrO2 deposition. The leakage current density at 5V is reduced from 10-1to5×10-6A /cm2. The subthreshold slope was improved to 91mV/decade. The MFISFETs maintain a threshold voltage window of about 1.1V after an elapsed time of 3000s. The mobility is 267cm2/Vs. The improvements are most likely due to the reduction of interfacial layer thickness and the interface states at the ZrO2/Si interface.

Pixel structures to compensate nonuniform threshold voltage and mobility of polycrystalline silicon thin-film transistors using subthreshold current for large-size active matrix organic light-emitting diode displays

NASA Astrophysics Data System (ADS)

Na, Jun-Seok; Kwon, Oh-Kyong

2014-01-01

We propose pixel structures for large-size and high-resolution active matrix organic light-emitting diode (AMOLED) displays using a polycrystalline silicon (poly-Si) thin-film transistor (TFT) backplane. The proposed pixel structures compensate the variations of the threshold voltage and mobility of the driving TFT using the subthreshold current. The simulated results show that the emission current error of the proposed pixel structure B ranges from -2.25 to 2.02 least significant bit (LSB) when the variations of the threshold voltage and mobility of the driving TFT are ±0.5 V and ±10%, respectively.

Subthreshold psychotic symptom distress, self-stigma, and peer social support among college students with mental health concerns.

PubMed

Denenny, Danielle; Thompson, Elizabeth; Pitts, Steven C; Dixon, Lisa B; Schiffman, Jason

2015-06-01

The primary aim of this study was to explore the potential moderating effect of social support on the relation between distress caused by psychosis risk symptoms and self-stigma among college students with mental health diagnoses. Participants were young adult college students who endorsed having a past or present mental health diagnosis (n = 63). Self-report data were examined from the Prodromal Questionnaire-Brief, a measure of subthreshold psychosis risk symptoms; the Self-Concurrence/Application subscale of the Self-Stigma of Mental Illness Scale, a measure of self-stigma; and the Friendships subscale of the Lubben Social Network Scale-Revised, a measure of social support from peers. There was a modest direct relation between distress associated with psychosis risk symptoms and self-stigma. There was a larger relation between distress from risk symptoms and self-stigma for those with low social support compared to those with mean and high social support. Although causality cannot be determined based on this study, a strong relation between symptom distress and stigma was found among those reporting low peer social support. Interventions that target both self-stigma and social support might be relevant for young adults with a history of mental health concerns who currently endorse subthreshold psychotic symptoms. (c) 2015 APA, all rights reserved).

Competition model for aperiodic stochastic resonance in a Fitzhugh-Nagumo model of cardiac sensory neurons.

PubMed

Kember, G C; Fenton, G A; Armour, J A; Kalyaniwalla, N

2001-04-01

Regional cardiac control depends upon feedback of the status of the heart from afferent neurons responding to chemical and mechanical stimuli as transduced by an array of sensory neurites. Emerging experimental evidence shows that neural control in the heart may be partially exerted using subthreshold inputs that are amplified by noisy mechanical fluctuations. This amplification is known as aperiodic stochastic resonance (ASR). Neural control in the noisy, subthreshold regime is difficult to see since there is a near absence of any correlation between input and the output, the latter being the average firing (spiking) rate of the neuron. This lack of correlation is unresolved by traditional energy models of ASR since these models are unsuitable for identifying "cause and effect" between such inputs and outputs. In this paper, the "competition between averages" model is used to determine what portion of a noisy, subthreshold input is responsible, on average, for the output of sensory neurons as represented by the Fitzhugh-Nagumo equations. A physiologically relevant conclusion of this analysis is that a nearly constant amount of input is responsible for a spike, on average, and this amount is approximately independent of the firing rate. Hence, correlation measures are generally reduced as the firing rate is lowered even though neural control under this model is actually unaffected.

Restoring the encoding properties of a stochastic neuron model by an exogenous noise

PubMed Central

Paffi, Alessandra; Camera, Francesca; Apollonio, Francesca; d'Inzeo, Guglielmo; Liberti, Micaela

2015-01-01

Here we evaluate the possibility of improving the encoding properties of an impaired neuronal system by superimposing an exogenous noise to an external electric stimulation signal. The approach is based on the use of mathematical neuron models consisting of stochastic HH-like circuit, where the impairment of the endogenous presynaptic inputs is described as a subthreshold injected current and the exogenous stimulation signal is a sinusoidal voltage perturbation across the membrane. Our results indicate that a correlated Gaussian noise, added to the sinusoidal signal can significantly increase the encoding properties of the impaired system, through the Stochastic Resonance (SR) phenomenon. These results suggest that an exogenous noise, suitably tailored, could improve the efficacy of those stimulation techniques used in neuronal systems, where the presynaptic sensory neurons are impaired and have to be artificially bypassed. PMID:25999845

Interplay of intrinsic and synaptic conductances in the generation of high-frequency oscillations in interneuronal networks with irregular spiking.

PubMed

Baroni, Fabiano; Burkitt, Anthony N; Grayden, David B

2014-05-01

High-frequency oscillations (above 30 Hz) have been observed in sensory and higher-order brain areas, and are believed to constitute a general hallmark of functional neuronal activation. Fast inhibition in interneuronal networks has been suggested as a general mechanism for the generation of high-frequency oscillations. Certain classes of interneurons exhibit subthreshold oscillations, but the effect of this intrinsic neuronal property on the population rhythm is not completely understood. We study the influence of intrinsic damped subthreshold oscillations in the emergence of collective high-frequency oscillations, and elucidate the dynamical mechanisms that underlie this phenomenon. We simulate neuronal networks composed of either Integrate-and-Fire (IF) or Generalized Integrate-and-Fire (GIF) neurons. The IF model displays purely passive subthreshold dynamics, while the GIF model exhibits subthreshold damped oscillations. Individual neurons receive inhibitory synaptic currents mediated by spiking activity in their neighbors as well as noisy synaptic bombardment, and fire irregularly at a lower rate than population frequency. We identify three factors that affect the influence of single-neuron properties on synchronization mediated by inhibition: i) the firing rate response to the noisy background input, ii) the membrane potential distribution, and iii) the shape of Inhibitory Post-Synaptic Potentials (IPSPs). For hyperpolarizing inhibition, the GIF IPSP profile (factor iii)) exhibits post-inhibitory rebound, which induces a coherent spike-mediated depolarization across cells that greatly facilitates synchronous oscillations. This effect dominates the network dynamics, hence GIF networks display stronger oscillations than IF networks. However, the restorative current in the GIF neuron lowers firing rates and narrows the membrane potential distribution (factors i) and ii), respectively), which tend to decrease synchrony. If inhibition is shunting instead of hyperpolarizing, post-inhibitory rebound is not elicited and factors i) and ii) dominate, yielding lower synchrony in GIF networks than in IF networks.

Negative subthreshold psychotic symptoms distinguish 22q11.2 deletion syndrome from other neurodevelopmental disorders: A two-site study.

PubMed

Mekori-Domachevsky, Ehud; Guri, Yael; Yi, James; Weisman, Omri; Calkins, Monica E; Tang, Sunny X; Gross, Raz; McDonald-McGinn, Donna M; Emanuel, Beverly S; Zackai, Elaine H; Zalsman, Gil; Weizman, Abraham; Gur, Ruben C; Gur, Raquel E; Gothelf, Doron

2017-10-01

About one third of individuals with 22q11.2 deletion syndrome (22q11.2DS) develop schizophrenia. Notably, a full-blown psychotic disorder is usually preceded by subthreshold symptoms. Therefore, it is important to identify early signs of psychosis in this population, a task that is complicated by the intellectual disabilities typically seen in 22q11.2DS. We aimed to identify subthreshold psychotic symptoms that distinguish 22q11.2DS from other neurodevelopmental disorders. The study included two independent cohorts from Tel Aviv and Philadelphia. 22q11.2DS (N=171) and typically developing (TD; N=832) individuals were enrolled at both sites and further compared to two groups with intellectual disabilities: Williams syndrome (WS; N=21) in the Tel Aviv cohort and idiopathic developmental disabilities (IDD; N=129) in the Philadelphia cohort. Participants and their primary caregivers were interviewed with the Structured Interview for Prodromal Symptoms (SIPS) and psychopathologies were assessed using standardized tools; general cognitive abilities were assessed with the Computerized Neurocognitive Battery. Negative/disorganized subthreshold syndrome was significantly more common in the 22q11.2DS group than in the WS (OR=3.90, 95% CI=1.34-11.34) or IDD (OR=5.05, 95% CI=3.01-10.08) groups. The 22q11.2DS group had higher scores than the two intellectual disabilities groups on several SIPS negative items, including avolition and decreased expression of emotion. Overall, there were few significant correlations between level of cognitive deficits and severity of negative symptoms in 22q11.2DS and only in the Tel Aviv cohort. Our findings suggest that 22q11.2DS individuals at the age of risk for developing psychosis should be closely monitored for negative symptoms. Copyright © 2016 Elsevier B.V. All rights reserved.

A Novel Form of Compensation in the Tg2576 Amyloid Mouse Model of Alzheimer’s Disease

PubMed Central

Somogyi, Attila; Katonai, Zoltán; Alpár, Alán; Wolf, Ervin

2016-01-01

One century after its first description, pathology of Alzheimer’s disease (AD) is still poorly understood. Amyloid-related dendritic atrophy and membrane alterations of susceptible brain neurons in AD, and in animal models of AD are widely recognized. However, little effort has been made to study the potential effects of combined morphological and membrane alterations on signal transfer and synaptic integration in neurons that build up affected neural networks in AD. In this study spatial reconstructions and electrophysiological measurements of layer II/III pyramidal neurons of the somatosensory cortex from wild-type (WT) and transgenic (TG) human amyloid precursor protein (hAPP) overexpressing Tg2576 mice were used to build faithful segmental cable models of these neurons. Local synaptic activities were simulated in various points of the dendritic arbors and properties of subthreshold dendritic impulse propagation and predictors of synaptic input pattern recognition ability were quantified and compared in modeled WT and TG neurons. Despite the widespread dendritic degeneration and membrane alterations in mutant mouse neurons, surprisingly little, or no change was detected in steady-state and 50 Hz sinusoidal voltage transfers, current transfers, and local and propagation delays of PSPs traveling along dendrites of TG neurons. Synaptic input pattern recognition ability was also predicted to be unaltered in TG neurons in two different soma-dendritic membrane models investigated. Our simulations predict the way how subthreshold dendritic signaling and pattern recognition are preserved in TG neurons: amyloid-related membrane alterations compensate for the pathological effects that dendritic atrophy has on subthreshold dendritic signal transfer and integration in layer II/III somatosensory neurons of this hAPP mouse model for AD. Since neither propagation of single PSPs nor integration of multiple PSPs (pattern recognition) changes in TG neurons, we conclude that AD-related neuronal hyperexcitability cannot be accounted for by altered subthreshold dendritic signaling in these neurons but hyperexcitability is related to changes in active membrane properties and network connectivity. PMID:27378850

Effect of combined oral doses of Δ(9)-tetrahydrocannabinol (THC) and cannabidiolic acid (CBDA) on acute and anticipatory nausea in rat models.

PubMed

Rock, Erin M; Connolly, Cassidy; Limebeer, Cheryl L; Parker, Linda A

2016-09-01

The purpose of this study was to evaluate the potential of oral combined cannabis constituents to reduce nausea. The objective of this study was to determine the effect of combining subthreshold oral doses of Δ(9)-tetrahydrocannabinol (THC) and cannabidiolic acid (CBDA) on acute and anticipatory nausea in rat models of conditioned gaping. The potential of intragastric (i.g.) administration of THC, CBDA, or combined doses, to interfere with acute nausea-induced conditioned gaping (acute nausea) or the expression of contextually elicited conditioned gaping (anticipatory nausea), was evaluated. For acute nausea, i.g. administration of subthreshold doses of THC (0.5 and 1 mg/kg) or CBDA (0.5 and 1 μg/kg) significantly suppressed acute nausea-induced gaping, whereas higher individual doses of both THC and CBDA were maximally effective. Combined i.g. administration of higher doses of THC and CBDA (2.5 mg/kg THC-2.5 μg/kg CBDA; 10 mg/kg THC-10 μg/kg CBDA; 20 mg/kg THC-20 μg/kg CBDA) also enhanced positive hedonic reactions elicited by saccharin solution during conditioning. For anticipatory nausea, combined subthreshold i.g. doses of THC (0.1 mg/kg) and CBDA (0.1 μg/kg) suppressed contextually elicited conditioned gaping. When administered i.g., THC was effective on its own at doses ranging from 1 to 10 mg/kg, but CBDA was only effective at 10 μg/kg. THC alone was equally effective by intraperitoneal (i.p.) and i.g. administration, whereas CBDA alone was more effective by i.p. administration (Rock et al. in Psychopharmacol (Berl) 232:4445-4454, 2015) than by i.g. administration. Oral administration of subthreshold doses of THC and CBDA may be an effective new treatment for acute nausea and anticipatory nausea and appetite enhancement in chemotherapy patients.

Attention Deficit Hyperactivity Disorder Symptoms and Psychosis in 22q11.2 Deletion Syndrome.

PubMed

Niarchou, Maria; Calkins, Monica E; Moore, Tyler M; Tang, Sunny X; McDonald-McGinn, Donna M; Zackai, Elaine H; Emanuel, Beverly S; Gur, Ruben C; Gur, Raquel E

2018-06-06

22q11.2 Deletion Syndrome (22q11.2DS) is associated with increased risk for schizophrenia in adulthood while Attention Deficit Hyperactivity Disorder (ADHD) is the most prevalent diagnosis in childhood. Inattention symptoms are pronounced in 22q11.2DS and given that attentional impairment is a core feature of schizophrenia, inattention symptoms may reflect underlying ADHD, psychosis, or both. We investigate whether inattention is associated with psychosis in 22q11.2DS and in other groups at risk for psychosis but without the deletion (ND) (idiopathic clinical risk and first degree family members of individuals with schizophrenia). One hundred thirty-seven individuals with 22q11.2DS (mean age: 14.0), 84 ND individuals with subthreshold psychosis (mean age: 16.9) and 31 ND individuals with family history of psychosis (mean age: 17.0) were included in the study. Psychopathology was assessed using research diagnostic assessments. ADHD total symptoms were associated with overall levels of subthreshold psychosis symptoms in 22q11.2DS (β = .8, P = .04). Inattention symptoms were specifically associated with positive (β = .5, P = .004), negative (β = .5, P = .03), and disorganized (β = .5, P < .001) symptoms, while hyperactivity-impulsivity symptoms were associated with disorganized symptoms (β = .5, P = .01). The prevalence of ADHD inattention symptoms was higher in 22q11.2DS with subthreshold psychosis compared to ND individuals with subthreshold psychosis (P < .001), even when adjusting for cognitive impairment and overall psychopathology. The pattern was similar when comparing individuals with 22q11.2DS and ND individuals with family history of psychosis. This is the first study to examine the associations between ADHD symptoms and psychosis in 22q11.2DS. Our findings support a potentially important role of ADHD inattention symptoms in psychosis in 22q11.2DS.

Interplay of Intrinsic and Synaptic Conductances in the Generation of High-Frequency Oscillations in Interneuronal Networks with Irregular Spiking

PubMed Central

Baroni, Fabiano; Burkitt, Anthony N.; Grayden, David B.

2014-01-01

High-frequency oscillations (above 30 Hz) have been observed in sensory and higher-order brain areas, and are believed to constitute a general hallmark of functional neuronal activation. Fast inhibition in interneuronal networks has been suggested as a general mechanism for the generation of high-frequency oscillations. Certain classes of interneurons exhibit subthreshold oscillations, but the effect of this intrinsic neuronal property on the population rhythm is not completely understood. We study the influence of intrinsic damped subthreshold oscillations in the emergence of collective high-frequency oscillations, and elucidate the dynamical mechanisms that underlie this phenomenon. We simulate neuronal networks composed of either Integrate-and-Fire (IF) or Generalized Integrate-and-Fire (GIF) neurons. The IF model displays purely passive subthreshold dynamics, while the GIF model exhibits subthreshold damped oscillations. Individual neurons receive inhibitory synaptic currents mediated by spiking activity in their neighbors as well as noisy synaptic bombardment, and fire irregularly at a lower rate than population frequency. We identify three factors that affect the influence of single-neuron properties on synchronization mediated by inhibition: i) the firing rate response to the noisy background input, ii) the membrane potential distribution, and iii) the shape of Inhibitory Post-Synaptic Potentials (IPSPs). For hyperpolarizing inhibition, the GIF IPSP profile (factor iii)) exhibits post-inhibitory rebound, which induces a coherent spike-mediated depolarization across cells that greatly facilitates synchronous oscillations. This effect dominates the network dynamics, hence GIF networks display stronger oscillations than IF networks. However, the restorative current in the GIF neuron lowers firing rates and narrows the membrane potential distribution (factors i) and ii), respectively), which tend to decrease synchrony. If inhibition is shunting instead of hyperpolarizing, post-inhibitory rebound is not elicited and factors i) and ii) dominate, yielding lower synchrony in GIF networks than in IF networks. PMID:24784237

A Novel Form of Compensation in the Tg2576 Amyloid Mouse Model of Alzheimer's Disease.

PubMed

Somogyi, Attila; Katonai, Zoltán; Alpár, Alán; Wolf, Ervin

2016-01-01

One century after its first description, pathology of Alzheimer's disease (AD) is still poorly understood. Amyloid-related dendritic atrophy and membrane alterations of susceptible brain neurons in AD, and in animal models of AD are widely recognized. However, little effort has been made to study the potential effects of combined morphological and membrane alterations on signal transfer and synaptic integration in neurons that build up affected neural networks in AD. In this study spatial reconstructions and electrophysiological measurements of layer II/III pyramidal neurons of the somatosensory cortex from wild-type (WT) and transgenic (TG) human amyloid precursor protein (hAPP) overexpressing Tg2576 mice were used to build faithful segmental cable models of these neurons. Local synaptic activities were simulated in various points of the dendritic arbors and properties of subthreshold dendritic impulse propagation and predictors of synaptic input pattern recognition ability were quantified and compared in modeled WT and TG neurons. Despite the widespread dendritic degeneration and membrane alterations in mutant mouse neurons, surprisingly little, or no change was detected in steady-state and 50 Hz sinusoidal voltage transfers, current transfers, and local and propagation delays of PSPs traveling along dendrites of TG neurons. Synaptic input pattern recognition ability was also predicted to be unaltered in TG neurons in two different soma-dendritic membrane models investigated. Our simulations predict the way how subthreshold dendritic signaling and pattern recognition are preserved in TG neurons: amyloid-related membrane alterations compensate for the pathological effects that dendritic atrophy has on subthreshold dendritic signal transfer and integration in layer II/III somatosensory neurons of this hAPP mouse model for AD. Since neither propagation of single PSPs nor integration of multiple PSPs (pattern recognition) changes in TG neurons, we conclude that AD-related neuronal hyperexcitability cannot be accounted for by altered subthreshold dendritic signaling in these neurons but hyperexcitability is related to changes in active membrane properties and network connectivity.

Adolescent Eating Disorders Predict Psychiatric, High-Risk Behaviors and Weight Outcomes in Young Adulthood

PubMed Central

Micali, Nadia; Solmi, Francesca; Horton, Nicholas J.; Crosby, Ross D.; Eddy, Kamryn T.; Calzo, Jerel P.; Sonneville, Kendrin R.; Swanson, Sonja A.; Field, Alison E.

2015-01-01

Objective To investigate whether anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), and other specified feeding and eating disorders (OSFED), including purging disorder (PD), subthreshold BN, and BED at ages 14 and 16, are prospectively associated with later depression, anxiety disorders, alcohol and substance use, and self-harm. Method Eating disorders were ascertained at 14 and 16 years of age in 6,140 youth at age 14 (58% of those eligible) and 5,069 at age 16 (52% of those eligible) as part of the prospective Avon Longitudinal Study of Parents and Children (ALSPAC). Outcomes (depression, anxiety disorders, binge drinking, drug use, deliberate self-harm, weight status) were measured using interviews and questionnaires about 2 years following predictors. Generalized estimating equation models adjusting for gender, socio-demographic variables, and prior outcome were used to examine prospective associations between eating disorders and each outcome. Results All eating disorders were predictive of later anxiety disorders. AN, BN, BED, PD, and OSFED were prospectively associated with depression (respectively AN: odds ratio [OR]=1.39 [95% CIs: 1.00-1.94]; BN: OR=3.39[1.25-9.20]; BED: OR=2.00 [1.06-3.75]; PD: OR=2.56 [1.38-4.74]). All eating disorders but AN predicted drug use and deliberate self-harm (BN: OR=5.72[2.22-14.72], PD: OR=4.88[2.78-8.57], subthreshold BN: OR=3.97[1.44-10.98], subthreshold BED: OR=2.32[1.43-3.75]). Whilst BED and BN predicted obesity (respectively OR=3.58 [1.06-12.14] and OR=6.42 [1.69-24.30]), AN was prospectively associated with underweight. Conclusions Adolescent eating disorders, including subthreshold presentations, predict negative outcomes, including mental health disorders, substance use, deliberate self-harm, and weight outcomes. This study highlights the high public health and clinical burden of eating disorders among adolescents. PMID:26210334

Screening for DSM-5 Other Specified Feeding or Eating Disorder in a Weight-Loss Treatment–Seeking Obese Sample

PubMed Central

Gorman, Mark J.; Sogg, Stephanie; Lamont, Evan M.; Eddy, Kamryn T.; Becker, Anne E.; Thomas, Jennifer J.

2014-01-01

Objective: To evaluate the effectiveness of specific self-report questionnaires in detecting DSM-5 eating disorders identified via structured clinical interview in a weight-loss treatment–seeking obese sample, to improve eating disorder recognition in general clinical settings. Method: Individuals were recruited over a 3-month period (November 2, 2011, to January 10, 2012) when initially presenting to a hospital-based weight-management center in the northeastern United States, which offers evaluation and treatment for outpatients who are overweight or obese. Participants (N = 100) completed the Structured Clinical Interview for DSM-IV eating disorder module, a DSM-5 feeding and eating disorders interview, and a battery of self-report questionnaires. Results: Self-reports and interviews agreed substantially in the identification of bulimia nervosa (DSM-IV and DSM-5: tau-b = 0.71, P < .001) and binge-eating disorder (DSM-IV and DSM-5: tau-b = 0.60, P < .001), modestly for subthreshold binge-eating disorder (tau-b = 0.44, P < .001), and poorly for other subthreshold conditions (night-eating syndrome: tau-b = –0.04, P = .72, r = 0.06 [DSM-5]). Discussion: Current self-report assessments are likely to identify full syndrome DSM-5 eating disorders in treatment-seeking obese samples, but unlikely to detect DSM-5 other specified feeding or eating disorders. We propose specific content changes that might enhance clinical utility as suggestions for future evaluation. PMID:25667810

Recent Advances in Neutron Physics

ERIC Educational Resources Information Center

Feshbach, Herman; Sheldon, Eric

1977-01-01

Discusses new studies in neutron physics within the last decade, such as ultracold neutrons, neutron bottles, resonance behavior, subthreshold fission, doubly radiative capture, and neutron stars. (MLH)

A subthreshold aVLSI implementation of the Izhikevich simple neuron model.

PubMed

Rangan, Venkat; Ghosh, Abhishek; Aparin, Vladimir; Cauwenberghs, Gert

2010-01-01

We present a circuit architecture for compact analog VLSI implementation of the Izhikevich neuron model, which efficiently describes a wide variety of neuron spiking and bursting dynamics using two state variables and four adjustable parameters. Log-domain circuit design utilizing MOS transistors in subthreshold results in high energy efficiency, with less than 1pJ of energy consumed per spike. We also discuss the effects of parameter variations on the dynamics of the equations, and present simulation results that replicate several types of neural dynamics. The low power operation and compact analog VLSI realization make the architecture suitable for human-machine interface applications in neural prostheses and implantable bioelectronics, as well as large-scale neural emulation tools for computational neuroscience.

Current-mode subthreshold MOS implementation of the Herault-Jutten autoadaptive network

NASA Astrophysics Data System (ADS)

Cohen, Marc H.; Andreou, Andreas G.

1992-05-01

The translinear circuits in subthreshold MOS technology and current-mode design techniques for the implementation of neuromorphic analog network processing are investigated. The architecture, also known as the Herault-Jutten network, performs an independent component analysis and is essentially a continuous-time recursive linear adaptive filter. Analog I/O interface, weight coefficients, and adaptation blocks are all integrated on the chip. A small network with six neurons and 30 synapses was fabricated in a 2-microns n-well double-polysilicon, double-metal CMOS process. Circuit designs at the transistor level yield area-efficient implementations for neurons, synapses, and the adaptation blocks. The design methodology and constraints as well as test results from the fabricated chips are discussed.

Full-range electrical characteristics of WS{sub 2} transistors

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

Kumar, Jatinder; Bellus, Matthew Z.; Chiu, Hsin-Ying, E-mail: chiu@ku.edu

We fabricated transistors formed by few layers to bulk single crystal WS{sub 2} to quantify the factors governing charge transport. We established a capacitor network to analyze the full-range electrical characteristics of the channel, highlighting the role of quantum capacitance and interface trap density. We find that the transfer characteristics are mainly determined by the interplay between quantum and oxide capacitances. In the OFF-state, the interface trap density (<10{sup 12} cm{sup –2}) is a limiting factor for the subthreshold swing. Furthermore, the superior crystalline quality and the low interface trap density enabled the subthreshold swing to approach the theoretical limit onmore » a back-gated device on SiO{sub 2}/Si substrate.« less

Improvement in interfacial characteristics of low-voltage carbon nanotube thin-film transistors with solution-processed boron nitride thin films

NASA Astrophysics Data System (ADS)

Jeon, Jun-Young; Ha, Tae-Jun

2017-08-01

In this article, we demonstrate the potential of solution-processed boron nitride (BN) thin films for high performance single-walled carbon nanotube thin-film transistors (SWCNT-TFTs) with low-voltage operation. The use of BN thin films between solution-processed high-k dielectric layers improved the interfacial characteristics of metal-insulator-metal devices, thereby reducing the current density by three orders of magnitude. We also investigated the origin of improved device performance in SWCNT-TFTs by employing solution-processed BN thin films as an encapsulation layer. The BN encapsulation layer improves the electrical characteristics of SWCNT-TFTs, which includes the device key metrics of linear field-effect mobility, sub-threshold swing, and threshold voltage as well as the long-term stability against the aging effect in air. Such improvements can be achieved by reduced interaction of interfacial localized states with charge carriers. We believe that this work can open up a promising route to demonstrate the potential of solution-processed BN thin films on nanoelectronics.

Behavioural informatics for improving water hygiene practice based on IoT environment.

PubMed

Fu, Yang; Wu, Wenyan

2018-02-01

The development of Internet of Things (IoT) and latest Information and Communication Technologies (ICT) have changed the nature of healthcare monitoring and health behaviour intervention in many applications. Water hygiene and water conservation behaviour intervention as important influence factors to human health are gaining much attentions for improving sustained sanitation practice. Based on face-to-face delivery, typical behaviour intervention method is costly and hardly to provide all day access to personalised intervention guidance and feedbacks. In this study, we presented a behavioural information system and water use behaviour model using IoT platform. Using Expanded Theory of Planned Behaviour (ETPB) and adopted structure equation model, this study offers a solution for understanding the behaviour intervention mechanism and methodology for developing empirical model. A case study of behaviour intervention model is presented by utilising residential water conservation behaviour data collected in China. Results suggested that cultural differences have significant influences on the understanding of intervention drivers, promoting projects and increasing awareness, which could improve the behaviour intervention efficiency and further facilitate the improvement of water hygiene practice. The performance evaluation of water saving dimension is discussed as well in the paper. Copyright © 2017 Elsevier Inc. All rights reserved.

Doping Nitrogen in InGaZnO Thin Film Transistor with Double Layer Channel Structure.

PubMed

Chang, Sheng-Po; Shan, Deng

2018-04-01

This paper presents the electrical characteristics of doping nitrogen in an amorphous InGaZnO thin film transistor. The IGZO:N film, which acted as a channel layer, was deposited using RF sputtering with a nitrogen and argon gas mixture at room temperature. The optimized parameters of the IGZO:N/IGZO TFT are as follows: threshold voltage is 0.5 V, field effect mobility is 14.34 cm2V-1S-1. The on/off current ratio is 106 and subthreshold swing is 1.48 V/decade. The positive gate bias stress stability of InGaZnO doping with nitrogen shows improvement compared to doping with oxygen.

New Diagnostic and Therapeutic Approaches for Preventing the Progression of Diabetic Retinopathy

PubMed Central

Park, Young Gun; Roh, Young-Jung

2016-01-01

Diabetic retinopathy (DR) is a severe sight-threatening complication of diabetes mellitus. Retinal laser photocoagulation, antivascular endothelial growth factors, steroid therapy, and pars plana vitrectomy are now used extensively to treat advanced stages of diabetic retinopathy. Currently, diagnostic devices like ultrawide field fundus fluorescein angiography and the improvement of optical coherence tomography have provided quicker and more precise diagnosis of early diabetic retinopathy. Thus, treatment protocols have been modified accordingly. Various types of lasers, including the subthreshold micropulse laser and RPE-targeting laser, and selective targeted photocoagulation may be future alternatives to conventional retinal photocoagulation, with fewer complications. The new developed intravitreal medications and implants have provided more therapeutic options, with promising results. PMID:26881240

Degree Correlations Optimize Neuronal Network Sensitivity to Sub-Threshold Stimuli

PubMed Central

Schmeltzer, Christian; Kihara, Alexandre Hiroaki; Sokolov, Igor Michailovitsch; Rüdiger, Sten

2015-01-01

Information processing in the brain crucially depends on the topology of the neuronal connections. We investigate how the topology influences the response of a population of leaky integrate-and-fire neurons to a stimulus. We devise a method to calculate firing rates from a self-consistent system of equations taking into account the degree distribution and degree correlations in the network. We show that assortative degree correlations strongly improve the sensitivity for weak stimuli and propose that such networks possess an advantage in signal processing. We moreover find that there exists an optimum in assortativity at an intermediate level leading to a maximum in input/output mutual information. PMID:26115374

Public knowledge, attitudes and behaviour regarding people with mental illness in England 2009-2012.

PubMed

Evans-Lacko, Sara; Henderson, Claire; Thornicroft, Graham

2013-04-01

Public stigma against people with mental health problems is damaging to individuals with mental illness and is associated with substantial societal burden. To investigate whether public knowledge, attitudes and behaviour in relation to people with mental health problems have improved among the English population since the inception of the Time To Change programme in 2009. We analysed longitudinal trends in public knowledge, attitudes and behaviour between 2009 and 2012 among a nationally representative sample of English adults. There were improvements in intended behaviour (0.07 standard deviation units, 95% CI 0.01-0.14) and a non-significant trend for improvement in attitudes (P = 0.08) among the English population. There was, however, no significant improvement in knowledge or reported behaviour. The findings provide support for effectiveness of the national Time to Change programme against stigma and discrimination in improving attitudes and intended behaviour, but not knowledge, among the public in England.

Improvement of the positive bias stability of a-IGZO TFTs by the HCN treatment

NASA Astrophysics Data System (ADS)

Kim, Myeong-Ho; Choi, Myung-Jea; Kimura, Katsuya; Kobayashi, Hikaru; Choi, Duck-Kyun

2016-12-01

In recent years, many researchers have attempted to improve the bias stability of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs). In this study, the hydrogen cyanide (HCN) treatment was carried out to improve the positive bias stability of bottom-gate a-IGZO TFTs. The HCN treatment was performed using a 0.1 M HCN solution with a pH of 10 at room temperature. Before applying the positive bias stress, there were no differences in the major electrical properties, including the saturation mobility (μsat), threshold voltage (Vth), and subthreshold swing (S/S), between HCN-treated and non-HCN-treated devices. However, after applying the positive bias stress, the HCN-treated device showed superior bias stability compared to the non-HCN-treated device. This difference is associated with the passivation of the defect states and the surface of the back-channel layer of the HCN-treated device by cyanide ions.

Improved performance of nanoscale junctionless tunnel field-effect transistor based on gate engineering approach

NASA Astrophysics Data System (ADS)

Molaei Imen Abadi, Rouzbeh; Sedigh Ziabari, Seyed Ali

2016-11-01

In this paper, a first qualitative study on the performance characteristics of dual-work function gate junctionless TFET (DWG-JLTFET) on the basis of energy band profile modulation is investigated. A dual-work function gate technique is used in a JLTFET in order to create a downward band bending on the source side similar to PNPN structure. Compared with the single-work function gate junctionless TFET (SWG-JLTFET), the numerical simulation results demonstrated that the DWG-JLTFET simultaneously optimizes the ON-state current, the OFF-state leakage current, and the threshold voltage and also improves average subthreshold slope. It is illustrated that if appropriate work functions are selected for the gate materials on the source side and the drain side, the JLTFET exhibits a considerably improved performance. Furthermore, the optimization design of the tunnel gate length ( L Tun) for the proposed DWG-JLTFET is studied. All the simulations are done in Silvaco TCAD for a channel length of 20 nm using the nonlocal band-to-band tunneling (BTBT) model.

NINE-YEAR FOLLOW-UP OF SPECIFIC PHOBIA IN A POPULATION SAMPLE OF OLDER PEOPLE.

PubMed

Sigström, Robert; Skoog, Ingmar; Karlsson, Björn; Nilsson, Johan; Östling, Svante

2016-04-01

Little is known about the long-term course of specific phobia (SP) in the general population. We examined the prevalence and course of SP and subthreshold fears in an older population followed over 9 years. A psychiatric examination was performed in a population-based sample of 558 70-year-olds, among whom 303 dementia-free survivors were followed up at both ages 75 and 79. Fears were rated with respect to level of anxiety and social or other consequences. DSM-IV SP was diagnosed when fears were associated with prominent anxiety and had social or other consequences. All other fears were labeled subthreshold fears. The prevalence of SP declined from 9.9% at age 70 to 4.0% at age 79. The reason was that the prevalence of fears associated with prominent anxiety (mandatory in the diagnosis) decreased whereas the prevalence of fears that gave social or other consequences remained stable. A total of 14.5% of the population had SP at least once during the study. Among these, 11.4% had SP and 65.9% had specific fear at all three examinations. The prevalence of fears associated with prominent anxiety decreased with age, resulting in an overall decline in the prevalence of SP. SP seems to be a fluctuating disorder, and in most cases an exacerbation of chronic subthreshold fears. © 2015 Wiley Periodicals, Inc.

Olivary subthreshold oscillations and burst activity revisited

PubMed Central

Bazzigaluppi, Paolo; De Gruijl, Jornt R.; van der Giessen, Ruben S.; Khosrovani, Sara; De Zeeuw, Chris I.; de Jeu, Marcel T. G.

2012-01-01

The inferior olive (IO) forms one of the major gateways for information that travels to the cerebellar cortex. Olivary neurons process sensory and motor signals that are subsequently relayed to Purkinje cells. The intrinsic subthreshold membrane potential oscillations of the olivary neurons are thought to be important for gating this flow of information. In vitro studies have revealed that the phase of the subthreshold oscillation determines the size of the olivary burst and may gate the information flow or encode the temporal state of the olivary network. Here, we investigated whether the same phenomenon occurred in murine olivary cells in an intact olivocerebellar system using the in vivo whole-cell recording technique. Our in vivo findings revealed that the number of wavelets within the olivary burst did not encode the timing of the spike relative to the phase of the oscillation but was related to the amplitude of the oscillation. Manipulating the oscillation amplitude by applying Harmaline confirmed the inverse relationship between the amplitude of oscillation and the number of wavelets within the olivary burst. Furthermore, we demonstrated that electrotonic coupling between olivary neurons affect this modulation of the olivary burst size. Based on these results, we suggest that the olivary burst size might reflect the “expectancy” of a spike to occur rather than the spike timing, and that this process requires the presence of gap junction coupling. PMID:23189043

Continuations of the nonlinear Schrödinger equation beyond the singularity

NASA Astrophysics Data System (ADS)

Fibich, G.; Klein, M.

2011-07-01

We present four continuations of the critical nonlinear Schrödinger equation (NLS) beyond the singularity: (1) a sub-threshold power continuation, (2) a shrinking-hole continuation for ring-type solutions, (3) a vanishing nonlinear-damping continuation and (4) a complex Ginzburg-Landau (CGL) continuation. Using asymptotic analysis, we explicitly calculate the limiting solutions beyond the singularity. These calculations show that for generic initial data that lead to a loglog collapse, the sub-threshold power limit is a Bourgain-Wang solution, both before and after the singularity, and the vanishing nonlinear-damping and CGL limits are a loglog solution before the singularity, and have an infinite-velocity expanding core after the singularity. Our results suggest that all NLS continuations share the universal feature that after the singularity time Tc, the phase of the singular core is only determined up to multiplication by eiθ. As a result, interactions between post-collapse beams (filaments) become chaotic. We also show that when the continuation model leads to a point singularity and preserves the NLS invariance under the transformation t → -t and ψ → ψ*, the singular core of the weak solution is symmetric with respect to Tc. Therefore, the sub-threshold power and the shrinking-hole continuations are symmetric with respect to Tc, but continuations which are based on perturbations of the NLS equation are generically asymmetric.

Predictors of first episode unipolar major depression in individuals with and without sub-threshold depressive symptoms: A prospective, population-based study

PubMed Central

Peters, Amy T.; Shankman, Stewart A.; Deckersbach, Thilo; West, Amy E.

2015-01-01

Background The aim of this study is to assess predictors of first-episode major depression in a community-based sample of adults with and without sub-threshold depression. Method Data were from Waves 1 & 2 of the National Epidemiological Survey on Alcohol and Related Conditions (NESARC). Participants meeting criteria for a sub-threshold depressive episode (sMDE; n = 3,901) reported lifetime depressed mood/loss of interest lasting at least two weeks and at least two of the seven other DSM-IV symptoms of MDD. Predictors of MDE 3 years later were compared in those with and without (n = 31,022) sMDE. Results Being female, history of alcohol or substance use, and child abuse increased the odds of developing MDD to a greater degree in individuals without sMDE relative to those with sMDE. Among those with sMDE and additional risk factors (low education, substance use), younger age was associated with marginally increased risk of MDD. Conclusion Several demographic risk factors may help identify individuals at risk for developing MDD in individuals who have not experienced an sMDE who may be candidates for early intervention. Future work should assess whether preventative interventions targeting substance/alcohol use and child abuse could reduce the risk of depression. PMID:26343831

Efficacy of sub-threshold focused ultrasound irradiation against pancreatic cancer xenografts evaluated using magnetic resonance imaging

PubMed Central

Chen, Yini; Gao, Yihui; Wu, Lei

2017-01-01

We investigated the efficacy and optimal period for using magnetic resonance imaging (MRI) to detect effects of sub-threshold focused ultrasound (FUS) irradiation. Nude mice bearing pancreatic cancer xenografts were subjected to MRI and pathology examnation before, and 24 h, 48 h, 2 weeks after irradiation, which were used to evaluate therapeutic effects of FUS. Tumor volumes were lower post-treatment than control group (P < 0.05). The T1WI turbo spin echo (T1WI-TSE) sequence was similar signal before and after treatment. On T1 enhanced scanning sequence (T1WI-SPIR) imaging, ablation lesions appeared as patchy areas of low signal after 24 h and 48 h. After 2 weeks, the ablation lesions contained low signal areas with clear borders. Hematoxylin and eosin (HE) staining revealed small vessels at ablation lesions with no obvious boundary between cell injury areas and normal tumor cells areas in early-stage, while revealed obvious boundaries 2 weeks post-treatment. Terminal deoxynucleotidyl transferase-modified, dUTP nick-end labeling (TUNEL) staining showed cell apoptosis in early-stage, and revealed reduced apoptotic cells and increased necrotic cell areas 2 weeks later. These findings indicate sub-threshold FUS induces pancreatic cancer cell apoptosis and inhibits tumor growth. Contrast-enhanced MRI delineated the ablation lesions better 2 weeks post-treatment than early stage. PMID:29113316

Pain, not chronic disease, is associated with the recurrence of depressive and anxiety disorders

PubMed Central

2014-01-01

Background Studies suggest that poor physical health might be associated with increased depression and anxiety recurrence. The objectives of this study were to determine whether specific chronic diseases and pain characteristics are associated with depression and anxiety recurrence and to examine whether such associations are mediated by subthreshold depressive or anxiety symptoms. Methods 1122 individuals with remitted depressive or anxiety disorder (Netherlands Study of Depression and Anxiety) were followed up for a period of four years. The impact of specific chronic diseases and pain characteristics on recurrence was assessed using Cox regression and mediation analyses. Results Chronic diseases were not associated with recurrence. Neck (HR 1.45, p < .01), chest (HR 1.65, p < .01), abdominal (HR 1.52, p < .01) pain, an increase in the number of pain locations (HR 1.10, p < .01) and pain severity (HR 1.18, p = .01) were associated with an increased risk of depression recurrence but not anxiety. Subthreshold depressive symptoms mediated the associations between pain and depression recurrence. Conclusions Pain, not chronic disease, increases the likelihood of depression recurrence, largely through its association with aggravated subthreshold depressive symptoms. These findings support the idea of the existence of a mutually reinforcing mechanism between pain and depression and are indicative of the importance of shedding light on neurobiological links in order to optimize pain and depression management. PMID:24965597

A Steep-Slope Transistor Combining Phase-Change and Band-to-Band-Tunneling to Achieve a sub-Unity Body Factor.

PubMed

Vitale, Wolfgang A; Casu, Emanuele A; Biswas, Arnab; Rosca, Teodor; Alper, Cem; Krammer, Anna; Luong, Gia V; Zhao, Qing-T; Mantl, Siegfried; Schüler, Andreas; Ionescu, A M

2017-03-23

Steep-slope transistors allow to scale down the supply voltage and the energy per computed bit of information as compared to conventional field-effect transistors (FETs), due to their sub-60 mV/decade subthreshold swing at room temperature. Currently pursued approaches to achieve such a subthermionic subthreshold swing consist in alternative carrier injection mechanisms, like quantum mechanical band-to-band tunneling (BTBT) in Tunnel FETs or abrupt phase-change in metal-insulator transition (MIT) devices. The strengths of the BTBT and MIT have been combined in a hybrid device architecture called phase-change tunnel FET (PC-TFET), in which the abrupt MIT in vanadium dioxide (VO 2 ) lowers the subthreshold swing of strained-silicon nanowire TFETs. In this work, we demonstrate that the principle underlying the low swing in the PC-TFET relates to a sub-unity body factor achieved by an internal differential gate voltage amplification. We study the effect of temperature on the switching ratio and the swing of the PC-TFET, reporting values as low as 4.0 mV/decade at 25 °C, 7.8 mV/decade at 45 °C. We discuss how the unique characteristics of the PC-TFET open new perspectives, beyond FETs and other steep-slope transistors, for low power electronics, analog circuits and neuromorphic computing.

Improved child behavioural and emotional functioning after Circle of Security 20-week intervention.

PubMed

Huber, Anna; McMahon, Catherine; Sweller, Naomi

2015-01-01

This study examined the efficacy of the attachment-based Circle of Security 20-week intervention in improving child behavioural and emotional functioning. Participants were 83 parents of children (1-7 years) referred to a clinical service with concerns about their young children's behaviour. Parents (and teachers, when available) completed questionnaires assessing child protective factors, behavioural concerns, internalizing and externalizing problems, prior to and immediately after the intervention. The following were considered as potential moderators: child gender and age, parent representations, reflective functioning, child attachment indices and severity of presenting problems, prior to treatment. Results showed significant improvement for parent ratings of child protective factors, behavioural concerns, internalizing and externalizing symptoms, all ps < .05, and children with more severe problems showed most improvement. Teachers also reported improvements, but change was significant only for externalizing problems (p = .030). Findings suggest Circle of Security is effective in improving child behavioural and emotional functioning in clinically referred children aged 1-7 years.

Effect of a Web-Based Guided Self-help Intervention for Prevention of Major Depression in Adults With Subthreshold Depression: A Randomized Clinical Trial.

PubMed

Buntrock, Claudia; Ebert, David Daniel; Lehr, Dirk; Smit, Filip; Riper, Heleen; Berking, Matthias; Cuijpers, Pim

2016-05-03

Evidence-based treatments for major depressive disorder (MDD) are not very successful in improving functional and health outcomes. Attention has increasingly been focused on the prevention of MDD. To evaluate the effectiveness of a web-based guided self-help intervention for the prevention of MDD. Two-group randomized clinical trial conducted between March 1, 2013, and March 4, 2015. Participants were recruited in Germany from the general population via a large statutory health insurance company (ie, insurance funded by joint employer-employee contributions). Participants included 406 self-selected adults with subthreshold depression (Centre for Epidemiologic Studies Depression Scale score ≥16, no current MDD according to Diagnostic and Statistical Manual of Mental Disorders [Fourth Edition, Text Revision] criteria). All participants had unrestricted access to usual care (visits to the primary care clinician) and were randomized to either a web-based guided self-help intervention (cognitive-behavioral and problem-solving therapy supported by an online trainer; n = 202) or a web-based psychoeducation program (n = 204). The primary outcome was time to onset of MDD in the intervention group relative to the control group over a 12-month follow-up period as assessed by blinded diagnostic raters using the telephone-administered Structured Clinical Interview for DSM-IV Axis Disorders at 6- and 12-month follow-up, covering the period to the previous assessment. Among 406 randomized patients (mean age, 45 years; 73.9% women), 335 (82%) completed the telephone follow-up at 12 months. Fifty-five participants (27%) in the intervention group experienced MDD compared with 84 participants (41%) in the control group. Cox regression analyses controlling for baseline depressive symptom severity revealed a hazard ratio of 0.59 (95% CI, 0.42-0.82; P = .002) at 12-month follow-up. The number needed to treat to avoid 1 new case of MDD was 5.9 (95% CI, 3.9-14.6). Among patients with subthreshold depression, the use of a web-based guided self-help intervention compared with enhanced usual care reduced the incidence of MDD over 12 months. Further research is needed to understand whether the effects are generalizable to both first onset of depression and depression recurrence as well as efficacy without the use of an online trainer. German Clinical Trial Registry Identifier: DRKS00004709.

The effect of sexual transmission on Zika virus dynamics.

PubMed

Saad-Roy, C M; Ma, Junling; van den Driessche, P

2018-04-25

Zika virus is a human disease that may lead to neurological disorders in affected individuals, and may be transmitted vectorially (by mosquitoes) or sexually. A mathematical model of Zika virus transmission is formulated, taking into account mosquitoes, sexually active males and females, inactive individuals, and considering both vector transmission and sexual transmission from infectious males to susceptible females. Basic reproduction numbers are computed, and disease control strategies are evaluated. The effect of the incidence function used to model sexual transmission from infectious males to susceptible females is investigated. It is proved that for such functions that are sublinear, if the basic reproduction [Formula: see text], then the disease dies out and [Formula: see text] is a sharp threshold. Moreover, under certain conditions on model parameters and assuming mass action incidence for sexual transmission, it is proved that if [Formula: see text], there exists a unique endemic equilibrium that is globally asymptotically stable. However, under nonlinear incidence, it is shown that for certain functions backward bifurcation and Hopf bifurcation may occur, giving rise to subthreshold equilibria and periodic solutions, respectively. Numerical simulations for various parameter values are displayed to illustrate these behaviours.

High-performance a-IGZO thin-film transistor with conductive indium-tin-oxide buried layer

NASA Astrophysics Data System (ADS)

Ahn, Min-Ju; Cho, Won-Ju

2017-10-01

In this study, we fabricated top-contact top-gate (TCTG) structure of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) with a thin buried conductive indium-tin oxide (ITO) layer. The electrical performance of a-IGZO TFTs was improved by inserting an ITO buried layer under the IGZO channel. Also, the effect of the buried layer's length on the electrical characteristics of a-IGZO TFTs was investigated. The electrical performance of the transistors improved with increasing the buried layer's length: a large on/off current ratio of 1.1×107, a high field-effect mobility of 35.6 cm2/Vs, a small subthreshold slope of 116.1 mV/dec, and a low interface trap density of 4.2×1011 cm-2eV-1 were obtained. The buried layer a-IGZO TFTs exhibited enhanced transistor performance and excellent stability against the gate bias stress.

Low-temperature solution-processed zinc oxide field effect transistor by blending zinc hydroxide and zinc oxide nanoparticle in aqueous solutions

NASA Astrophysics Data System (ADS)

Shin, Hyeonwoo; Kang, Chan-mo; Baek, Kyu-Ha; Kim, Jun Young; Do, Lee-Mi; Lee, Changhee

2018-05-01

We present a novel methods of fabricating low-temperature (180 °C), solution-processed zinc oxide (ZnO) transistors using a ZnO precursor that is blended with zinc hydroxide [Zn(OH)2] and zinc oxide hydrate (ZnO • H2O) in an ammonium solution. By using the proposed method, we successfully improved the electrical performance of the transistor in terms of the mobility (μ), on/off current ratio (I on/I off), sub-threshold swing (SS), and operational stability. Our new approach to forming a ZnO film was systematically compared with previously proposed methods. An atomic forced microscopic (AFM) image and an X-ray photoelectron spectroscopy (XPS) analysis showed that our method increases the ZnO crystallite size with less OH‑ impurities. Thus, we attribute the improved electrical performance to the better ZnO film formation using the blending methods.

Device simulation of GeSn/GeSiSn pocket n-type tunnel field-effect transistor for analog and RF applications

NASA Astrophysics Data System (ADS)

Wang, Suyuan; Zheng, Jun; Xue, Chunlai; Li, Chuanbo; Zuo, Yuhua; Cheng, Buwen; Wang, Qiming

2017-11-01

We present the device simulations of analog and radio frequency (RF) performances of four double-gate pocket n-type tunneling field-effect transistors (NTFETs). The direct current (DC), analog and RF performances of the Ge-homo, GeSn-homo, GeSn/Ge and GeSn/GeSiSn NTFETs, are compared. The GeSn NTFETs greatly improve the on-state current (ION) and average subthreshold slope (SS), when compared with the Ge NTFET. Moreover, the GeSn/GeSiSn NTFET has the largest intrinsic gain (Av), and exhibits a suppressed ambipolar behavior, improved cut-off frequency (fT), and gain bandwidth product (GBW), according to the analyzed analog and RF figures of merit (FOM). Therefore, it can be concluded that the GeSn/GeSiSn NTFET has great potential as a promising candidate for the realization of future generation low-power analog/RF applications.

Dopingless ferroelectric tunnel FET architecture for the improvement of performance of dopingless n-channel tunnel FETs

NASA Astrophysics Data System (ADS)

Lahgere, Avinash; Panchore, Meena; Singh, Jawar

2016-08-01

In this paper, we propose a novel tunnel field-effect transistor (TFET) based on charge plasma (CP) and negative capacitance (NC) for enhanced ON-current and steep subthreshold swing (SS). It is shown that the replacement of standard insulator for gate stack with ferroelectric (Fe) insulator yields NC and high electric field at the tunneling junction. Similarly, use of dopingless silicon nanowire with CP has a genuine advantage in process engineering. Therefore, combination of both technology boosters (CP and NC) in the proposed device enable low thermal budget, process variation immunity, and excellent electrical characteristics in contrast with its counterpart dopingless (DL) TFET (DL-TFET). An optimized device accomplishes an impressive 10× improvement in on-current, 100× reduced leakage current, 3× more transconductance (gm), and on-off current ratio of ∼1011 as compared to DL-TFET.

[Electromagnetic radiation of non-thermal intensity and short exposition as a sub-threshold irritant for the central nervous system].

PubMed

Luk'ianova, S N

2013-01-01

This work represents generalization and the analysis of the long-term own materials characterizing reaction of the brain on electromagnetic radiation of low intensity (energy flow density in the continuous regime or in the impulse approximately 500 microW/sm2) and a short exposition (approximately 30 min). A set of the experimental results received on separate neurons, formations and brain as a whole give an idea about the reaction of the central nervous system to the studied influence. Comparison of these data with the corresponding responses to the known incentives (light, sound, electric current) testifies to the electromagnetic radiation of low energy flow density and a short exposition as a sub-threshold irritant for the central nervous system.

Numerical analysis of band tails in nanowires and their effects on the performance of tunneling field-effect transistors

NASA Astrophysics Data System (ADS)

Tanaka, Takahisa; Uchida, Ken

2018-06-01

Band tails in heavily doped semiconductors are one of the important parameters that determine transfer characteristics of tunneling field-effect transistors. In this study, doping concentration and doing profile dependences of band tails in heavily doped Si nanowires were analyzed by a nonequilibrium Green function method. From the calculated band tails, transfer characteristics of nanowire tunnel field-effect transistors were numerically analyzed by Wentzel–Kramer–Brillouin approximation with exponential barriers. The calculated transfer characteristics demonstrate that the band tails induced by dopants degrade the subthreshold slopes of Si nanowires from 5 to 56 mV/dec in the worst case. On the other hand, surface doping leads to a high drain current while maintaining a small subthreshold slope.

Effects of V2O5/Au bi-layer electrodes on the top contact Pentacene-based organic thin film transistors

NASA Astrophysics Data System (ADS)

Borthakur, Tribeni; Sarma, Ranjit

2017-05-01

Top-contact Pentacene-based organic thin film transistors (OTFTs) with a thin layer of Vanadium Pent-oxide between Pentacene and Au layer are fabricated. Here we have found that the devices with V2O5/Au bi-layer source-drain electrode exhibit better field-effect mobility, high on-off ratio, low threshold voltage and low sub-threshold slope than the devices with Au only. The field-effect mobility, current on-off ratio, threshold voltage and sub-threshold slope of V2O5/Au bi-layer OTFT estimated from the device with 15 nm thick V2O5 layer is .77 cm2 v-1 s-1, 7.5×105, -2.9 V and .36 V/decade respectively.

Recovery in dc and rf performance of off-state step-stressed AlGaN/GaN high electron mobility transistors with thermal annealing

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

Kim, Byung-Jae; Hwang, Ya-Hsi; Ahn, Shihyun

The recovery effects of thermal annealing on dc and rf performance of off-state step-stressed AlGaN/GaN high electron mobility transistors were investigated. After stress, reverse gate leakage current and sub-threshold swing increased and drain current on-off ratio decreased. However, these degradations were completely recovered after thermal annealing at 450 °C for 10 mins for devices stressed either once or twice. The trap densities, which were estimated by temperature-dependent drain-current sub-threshold swing measurements, increased after off-state step-stress and were reduced after subsequent thermal annealing. In addition, the small signal rf characteristics of stressed devices were completely recovered after thermal annealing.

Subthreshold Schottky-barrier thin-film transistors with ultralow power and high intrinsic gain

NASA Astrophysics Data System (ADS)

Lee, Sungsik; Nathan, Arokia

2016-10-01

The quest for low power becomes highly compelling in newly emerging application areas related to wearable devices in the Internet of Things. Here, we report on a Schottky-barrier indium-gallium-zinc-oxide thin-film transistor operating in the deep subthreshold regime (i.e., near the OFF state) at low supply voltages (<1 volt) and ultralow power (<1 nanowatt). By using a Schottky-barrier at the source and drain contacts, the current-voltage characteristics of the transistor were virtually channel-length independent with an infinite output resistance. It exhibited high intrinsic gain (>400) that was both bias and geometry independent. The transistor reported here is useful for sensor interface circuits in wearable devices where high current sensitivity and ultralow power are vital for battery-less operation.

High temperature-induced abnormal suppression of sub-threshold swing and on-current degradations under hot-carrier stress in a-InGaZnO thin film transistors

NASA Astrophysics Data System (ADS)

Tsai, Ming-Yen; Chang, Ting-Chang; Chu, Ann-Kuo; Hsieh, Tien-Yu; Chen, Te-Chih; Lin, Kun-Yao; Tsai, Wu-Wei; Chiang, Wen-Jen; Yan, Jing-Yi

2013-07-01

This letter investigates the effect of temperature on hot-carrier stress-induced degradation behavior in InGaZnO thin film transistors. After hot-carrier stress at 25 °C, serious on-current and subthreshold swing degradations are observed due to trap state generation near the drain side. For identical stress performed at elevated temperatures, current degradation in the I-V transfer curve under reverse mode is gradually suppressed and the anomalous hump in the gate-to-drain capacitance-voltage curve becomes more severe. These suppressed degradations and the more severe hump can be both attributed to hole-trapping near the drain side due to high drain bias at high temperature.

Analytical model of surface potential profiles and transfer characteristics for hetero stacked tunnel field-effect transistors

NASA Astrophysics Data System (ADS)

Xu, Hui Fang; Sun, Wen; Han, Xin Feng

2018-06-01

An analytical model of surface potential profiles and transfer characteristics for hetero stacked tunnel field-effect transistors (HS-TFETs) is presented for the first time, where hetero stacked materials are composed of two different bandgaps. The bandgap of the underlying layer is smaller than that of the upper layer. Under different device parameters (upper layer thickness, underlying layer thickness, and hetero stacked materials) and temperature, the validity of the model is demonstrated by the agreement of its results with the simulation results. Moreover, the results show that the HS-TFETs can obtain predominant performance with relatively slow changes of subthreshold swing (SS) over a wide drain current range, steep average subthreshold swing, high on-state current, and large on–off state current ratio.

The interaction between neurocognitive functioning, subthreshold psychotic symptoms and pharmacotherapy in 22q11.2 deletion syndrome: A longitudinal comparative study.

PubMed

Weinberger, R; Weisman, O; Guri, Y; Harel, T; Weizman, A; Gothelf, D

2018-02-01

The 22q11.2 deletion syndrome (22q11DS) is the most common genetic syndrome associated with schizophrenia. The goal of this study was to evaluate longitudinally the interaction between neurocognitive functioning, the presence of subthreshold psychotic symptoms (SPS) and conversion to psychosis in individuals with 22q11DS. In addition, we attempted to identify the specific neurocognitive domains that predict the longitudinal evolution of positive and negative SPS, as well as the effect of psychiatric medications on 22q11DS psychiatric and cognitive developmental trajectories. Forty-four participants with 22q11DS, 19 with Williams syndrome (WS) and 30 typically developing (TD) controls, age range 12-35years, were assessed at two time points (15.2±2.1months apart). Evaluation included the Structured Interview for Prodromal Symptoms (SIPS), structured psychiatric evaluation and the Penn Computerized Neurocognitive Battery (CNB). 22q11DS individuals with SPS had a yearly conversion rate to psychotic disorders of 8.8%, compared to none in both WS and TD controls. Baseline levels of negative SPS were associated with global neurocognitive performance (GNP), executive function and social cognition deficits, in individuals with 22q11DS, but not in WS. Deficits in GNP predicted negative SPS in 22q11DS and the emergence or persistence of negative SPS. 22q11DS individuals treated with psychiatric medications showed significant improvement in GNP score between baseline and follow-up assessments, an improvement that was not seen in untreated 22q11DS. Our results highlight the time-dependent interplay among positive and negative SPS symptoms, neurocognition and pharmacotherapy in the prediction of the evolution of psychosis in 22q11DS. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Attempts to improve and confidence in improving health behaviour in 40-49 year olds with and without coronary heart disease: The Hordaland Health Study.

PubMed

Solvang, Marte M; Norekvål, Tone M; Tell, Grethe S; Berge, Line I; Iversen, Marjolein M

2016-04-01

While the overall incidence of acute myocardial infarction in Norway decreased in 2001-2009, this was not observed for younger adults. Smoking cessation, physical activity and healthy diet are associated with reduced risk of recurrent cardiovascular events and mortality among individuals with established coronary heart disease (CHD). We investigated whether adults in their 40s with or without CHD had 1) attempted to improve their health behaviour during the previous year, and 2) had confidence in their ability to improve their health behaviour over the next five years. Study participants were 22,019 40-49 year olds from the Hordaland Health Study. Associations between improvements and intentions regarding health behaviours and prevalent CHD were assessed with logistic regression analyses. One hundred and seventy-five (0.8%) participants reported to have CHD. After controlling for demographic, lifestyle and psychosocial variables, attempts to improve health behaviour during the prior year were associated with a threefold increased odds of prevalent CHD (odds ratio 3.07; 95% confidence interval, 1.91-4.95). Confidence in improving health behaviour during the subsequent five years was not associated with increased odds of prevalent CHD. Adults in their 40s with CHD were more likely to have attempted to improve their health behaviour during the past year compared with those without CHD. Healthcare providers should take advantage of these positive attitudes to encourage further positive improvements. © The European Society of Cardiology 2015.

Behavioural disorders in children with epilepsy: early improvement after surgery

PubMed Central

Lendt, M; Helmstaedter, C; Kuczaty, S; Schramm, J; Elger, C

2000-01-01

OBJECTIVES—Epilepsy surgery has proved to be a successful intervention method to achieve freedom from seizures or seizure relief in children with pharmacoresistant epilepsy. Long term studies on operated children suggest that behavioural disorders, which are often seen before surgery, improve after surgery. However, the early postoperative development of behavioural problems has not been systematically evaluated.
METHODS—Parents of 28 children with pharmacoresistant focal epilepsies completed the child behaviour checklist (CBCL) preoperatively and 3 months after surgery. Surgeries comprised 24 focal resections (13 temporal, 11 extratemporal), two hemispherectomies, and two callosotomies. Twenty eight conservatively treated children with comparable CBCL scores served as a control group. A repeated measurement multivariate analysis of variance (MANOVA) and a regression analysis were computed to compare the development of behaviour between both groups and to identify predictors of postoperative changes in behaviour.
RESULTS—Preoperatively 39% of the children exhibited significant behavioural problems, a further 11% were within the borderline range. The MANOVA disclosed a significant interaction between time of examination and group (F=2.23, p<0.05). The surgery group showed significant improvements on the scales "internalising problems", "externalising problems", "attention problems", and "thought problems". Behavioural problems in the control group, however, remained unchanged. No changes were seen in social problems in both groups. The significant predictor of total behavioural improvement was a good seizure outcome (R2=0.11, p<0.05). Age, sex, onset, and duration of epilepsy, the site of the focus, and changes in antiepileptic drug regimen did not influence changes in behaviour.
CONCLUSIONS—The data demonstrate an early improvement of behavioural problems after epilepsy surgery in children. The behavioural improvements can be assumed to result directly from the removal of the epileptic focus. They are not predictable on the basis of information available preoperatively, but depend on the seizure outcome.

 PMID:11080225

Subthreshold Desensitization of Human Basophils Re-capitulates the Loss of syk and FcεRI expression Characterized by Other Methods of Desensitization

PubMed Central

MacGlashan, Donald

2012-01-01

Background Clinical desensitization of patients to drugs involves progressive exposure to escalating doses of drug over a period of 24 hours. In prior studies, this method was recapitulated in vitro to also demonstrate loss of mast cell or basophil responsiveness. However, most signaling studies of human basophils have identified changes in signaling by using other methods of inducing cellular desensitization. Objective This study examined two well-described endpoints of basophil desensitization, loss of syk or FcεRI expression, under conditions of subthreshold desensitization. Methods The loss of FceRI and syk was examined in human basophils. Results It was shown that both loss of syk and FcεRI/IgE occurred during an escalating series of stimulation (anti-IgE Ab) and that expression loss occurred despite the presence of little histamine release. If basophils were first cultured for 3 days in 10 ng/ml IL-3, the concentration-dependence of histamine release shifted to 100 fold lower concentrations of stimulus. However, loss of syk did not show any change in its EC50 while loss of FcεRI also shifted 100 fold. From the perspective of early signal element activation, the marked shift in the EC50 for histamine release was not accompanied by similar shifts in the EC50s for several signaling elements. The EC50s for phospho-Src, phospho-SHIP1, phospho-Syk, or phospho-Cbl did not change while the EC50s for phospho-Erk and the cytosolic calcium response did shift 100 fold. Conclusions These studies show that under normal conditions, subthreshold desensitization leads to loss of two critical signaling molecules (FcεRI and syk) but under at least one condition, treatment with IL-3, it is possible to markedly blunt the loss of syk, but not FcεRI, while executing a proper subthreshold titration. These data also suggest that IL-3 modifies only the sensitivity of signaling elements that are downstream of syk activation. PMID:22702505

Effectiveness of a stepped-care intervention to prevent major depression in patients with type 2 diabetes mellitus and/or coronary heart disease and subthreshold depression: A pragmatic cluster randomized controlled trial.

PubMed

Pols, Alide D; van Dijk, Susan E; Bosmans, Judith E; Hoekstra, Trynke; van Marwijk, Harm W J; van Tulder, Maurits W; Adriaanse, Marcel C

2017-01-01

Given the public health significance of poorly treatable co-morbid major depressive disorders (MDD) among patients with type 2 diabetes mellitus (DM2) and coronary heart disease (CHD), we need to investigate whether strategies to prevent the development of major depression could reduce its burden of disease. We therefore evaluated the effectiveness of a stepped-care program for subthreshold depression in comparison with usual care in patients with DM2 and/or CHD. A cluster randomized controlled trial, with 27 primary care centers serving as clusters. A total of 236 DM2 and/or CHD patients with subthreshold depression (nine item Patient Health Questionnaire (PHQ-9) score ≥ 6, no current MDD according to DSM-IV criteria) were allocated to the intervention group (N = 96) or usual care group (n = 140). The stepped-care program was delivered by trained practice nurses during one year and consisted of four sequential treatment steps: watchful waiting, guided self-help, problem solving treatment and referral to the general practitioner. The primary outcome was the 12-month cumulative incidence of MDD as measured with the Mini International Neuropsychiatric Interview (MINI). Secondary outcomes included severity of depression (measured by PHQ-9) at 3, 6, 9 and 12 months. Of 236 patients (mean age, 67,5 (SD 10) years; 54.7% men), 210 (89%) completed the MINI at 12 months. The cumulative incidence of MDD was 9 of 89 (10.1%) participants in the intervention group and 12 of 121 (9.9%) participants in the usual care group. We found no statistically significant overall effect of the intervention (OR = 1.21; 95% confidence interval (0.12 to 12.41)) and there were no statistically significant differences in the course or severity of depressive symptoms between the two groups. This study suggest that Step-Dep was not more effective in preventing MDD than usual care in a primary care population with DM2 and/or CHD and subthreshold depression.

Network activity influences the subthreshold and spiking visual responses of pyramidal neurons in the three-layer turtle cortex.

PubMed

Wright, Nathaniel C; Wessel, Ralf

2017-10-01

A primary goal of systems neuroscience is to understand cortical function, typically by studying spontaneous and stimulus-modulated cortical activity. Mounting evidence suggests a strong and complex relationship exists between the ongoing and stimulus-modulated cortical state. To date, most work in this area has been based on spiking in populations of neurons. While advantageous in many respects, this approach is limited in scope: it records the activity of a minority of neurons and gives no direct indication of the underlying subthreshold dynamics. Membrane potential recordings can fill these gaps in our understanding, but stable recordings are difficult to obtain in vivo. Here, we recorded subthreshold cortical visual responses in the ex vivo turtle eye-attached whole brain preparation, which is ideally suited for such a study. We found that, in the absence of visual stimulation, the network was "synchronous"; neurons displayed network-mediated transitions between hyperpolarized (Down) and depolarized (Up) membrane potential states. The prevalence of these slow-wave transitions varied across turtles and recording sessions. Visual stimulation evoked similar Up states, which were on average larger and less reliable when the ongoing state was more synchronous. Responses were muted when immediately preceded by large, spontaneous Up states. Evoked spiking was sparse, highly variable across trials, and mediated by concerted synaptic inputs that were, in general, only very weakly correlated with inputs to nearby neurons. Together, these results highlight the multiplexed influence of the cortical network on the spontaneous and sensory-evoked activity of individual cortical neurons. NEW & NOTEWORTHY Most studies of cortical activity focus on spikes. Subthreshold membrane potential recordings can provide complementary insight, but stable recordings are difficult to obtain in vivo. Here, we recorded the membrane potentials of cortical neurons during ongoing and visually evoked activity. We observed a strong relationship between network and single-neuron evoked activity spanning multiple temporal scales. The membrane potential perspective of cortical dynamics thus highlights the influence of intrinsic network properties on visual processing. Copyright © 2017 the American Physiological Society.

Adolescent Eating Disorders Predict Psychiatric, High-Risk Behaviors and Weight Outcomes in Young Adulthood.

PubMed

Micali, Nadia; Solmi, Francesca; Horton, Nicholas J; Crosby, Ross D; Eddy, Kamryn T; Calzo, Jerel P; Sonneville, Kendrin R; Swanson, Sonja A; Field, Alison E

2015-08-01

To investigate whether anorexia nervosa (AN), bulimia nervosa (BN), binge eating disorder (BED), and other specified feeding and eating disorders (OSFED), including purging disorder (PD), subthreshold BN, and BED at ages 14 and 16 years, are prospectively associated with later depression, anxiety disorders, alcohol and substance use, and self-harm. Eating disorders were ascertained at ages 14 and 16 years in 6,140 youth at age 14 (58% of those eligible) and 5,069 at age 16 (52% of those eligible) as part of the prospective Avon Longitudinal Study of Parents and Children (ALSPAC). Outcomes (depression, anxiety disorders, binge drinking, drug use, deliberate self-harm, weight status) were measured using interviews and questionnaires about 2 years after predictors. Generalized estimating equation models adjusting for gender, socio-demographic variables, and prior outcome were used to examine prospective associations between eating disorders and each outcome. All eating disorders were predictive of later anxiety disorders. AN, BN, BED, PD, and OSFED were prospectively associated with depression (respectively AN: odds ratio [OR] = 1.39, 95% CI = 1.00-1.94; BN: OR = 3.39, 95% CI = 1.25-9.20; BED: OR = 2.00, 95% CI = 1.06-3.75; and PD: OR = 2.56, 95% CI = 1.38-4.74). All eating disorders but AN predicted drug use and deliberate self-harm (BN: OR = 5.72, 95% CI = 2.22-14.72; PD: OR = 4.88, 95% CI = 2.78-8.57; subthreshold BN: OR = 3.97, 95% CI = 1.44-10.98; and subthreshold BED: OR = 2.32, 95% CI = 1.43-3.75). Although BED and BN predicted obesity (respectively OR = 3.58, 95% CI = 1.06-12.14 and OR = 6.42, 95% CI = 1.69-24.30), AN was prospectively associated with underweight. Adolescent eating disorders, including subthreshold presentations, predict negative outcomes, including mental health disorders, substance use, deliberate self-harm, and weight outcomes. This study highlights the high public health and clinical burden of eating disorders among adolescents. Copyright © 2015 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

Inter-informant agreement and prevalence estimates for mood syndromes: direct interview vs. family history method.

PubMed

Vandeleur, C L; Rothen, S; Lustenberger, Y; Glaus, J; Castelao, E; Preisig, M

2015-01-15

The use of the family history method is recommended in family studies as a type of proxy interview of non-participating relatives. However, using different sources of information can result in bias as direct interviews may provide a higher likelihood of assigning diagnoses than family history reports. The aims of the present study were to: (1) compare diagnoses for threshold and subthreshold mood syndromes from interviews to those relying on information from relatives; (2) test the appropriateness of lowering the diagnostic threshold and combining multiple reports from the family history method to obtain comparable prevalence estimates to the interviews; (3) identify factors that influence the likelihood of agreement and reporting of disorders by informants. Within a family study, 1621 informant-index subject pairs were identified. DSM-5 diagnoses from direct interviews of index subjects were compared to those derived from family history information provided by their first-degree relatives. (1) Inter-informant agreement was acceptable for Mania, but low for all other mood syndromes. (2) Except for Mania and subthreshold depression, the family history method provided significantly lower prevalence estimates. The gap improved for all other syndromes after lowering the threshold of the family history method. (3) Individuals who had a history of depression themselves were more likely to report depression in their relatives. Low proportion of affected individuals for manic syndromes and lack of independence of data. The higher likelihood of reporting disorders by affected informants entails the risk of overestimation of the size of familial aggregation of depression. Copyright © 2014 Elsevier B.V. All rights reserved.

Social cognition in bipolar disorder: Focus on emotional intelligence.

PubMed

Varo, C; Jimenez, E; Solé, B; Bonnín, C M; Torrent, C; Valls, E; Morilla, I; Lahera, G; Martínez-Arán, A; Vieta, E; Reinares, M

2017-08-01

The present study aims to characterize emotional intelligence (EI) variability in a sample of euthymic bipolar disorder (BD) patients through the Mayer- Salovey-Caruso Emotional Intelligence Test (MSCEIT). A total of 134 euthymic BD outpatients were recruited and divided into three groups according to the total Emotional Intelligence Quotient (EIQ) score of the MSCEIT, following a statistical criterion of scores 1.5SDs above/below the normative group mean, as follows: a low performance (LP) group (EIQ <85), a normal performance (NP) group (85≤EIQ≤115), and a high performance (HP) group (EIQ >115). Afterwards, main sociodemographic, clinical, functional and neurocognitive variables were compared between the groups. Three groups were identified: 1) LP group (n=16, 12%), 2) NP group (n=93, 69%) and 3) HP group (n=25, 19%). There were significant differences between the groups in premorbid intelligence quotient (IQ) (p=0.010), axis II comorbidity (p=0.008), subthreshold depressive symptoms (p=0.027), general functioning (p=0.013) and in four specific functional domains: autonomy, occupation, interpersonal relations and leisure time. Significant differences in neurocognitive performance were found between groups with the LP group showing the lowest attainments. The cross-sectional design of the study. Our results suggest that EI variability among BD patients, assessed through MSCEIT, is lower than expected. EI could be associated with premorbid IQ, subthreshold depressive symptoms, neurocognitive performance and general functioning. The identification of different profiles of SC may help guide specific interventions for distinct patient subgroups aimed at improving social cognition, neurocognitive performance and psychosocial functioning. Copyright © 2017 Elsevier B.V. All rights reserved.

Escalation to Major Depressive Disorder among Adolescents with Subthreshold Depressive Symptoms: Evidence of Distinct Subgroups at Risk

PubMed Central

Hill, Ryan M.; Pettit, Jeremy W.; Lewinsohn, Peter M.; Seeley, John R.; Klein, Daniel N.

2014-01-01

Background The presence of subthreshold depressive symptoms (SubD) in adolescence is associated with high prospective risk of developing Major Depressive Disorder (MDD). Little is known about variables that predict escalation from SubD to MDD. This study used a longitudinal prospective design in a community sample of adolescents to identify combinations of risk factors that predicted escalation from SubD to MDD. Methods Classification tree analysis was used to identify combinations of risk factors that improved the sensitivity and specificity of prediction of MDD onset among 424 adolescents with a lifetime history of SubD. Results Of the 424, 144 developed MDD during the follow-up period. Evidence for multiple subgroups was found: Among adolescents with poor friend support, the highest risk of escalation was among participants with lifetime histories of an anxiety or substance use disorder. Among adolescents with high friend support, those reporting multiple major life events in the past year or with a history of an anxiety disorder were at highest risk of escalation. Limitations Study findings may not inform prevention efforts for individuals who first develop SubD during adulthood. This study did not examine the temporal ordering of predictors involved in escalation from SubD to MDD. Conclusions Adolescents with a history of SubD were at highest risk of escalation to MDD in the presence of poor friend support and an anxiety or substance use disorder, or in the presence of better friend support, multiple major life events, and an anxiety disorder. Findings may inform case identification approaches for adolescent depression prevention programs. PMID:24655777

Noradrenergic modulation of masseter muscle activity during natural rapid eye movement sleep requires glutamatergic signalling at the trigeminal motor nucleus

PubMed Central

Schwarz, Peter B; Mir, Saba; Peever, John H

2014-01-01

Noradrenergic neurotransmission in the brainstem is closely coupled to changes in muscle activity across the sleep–wake cycle, and noradrenaline is considered to be a key excitatory neuromodulator that reinforces the arousal-related stimulus on motoneurons to drive movement. However, it is unknown if α-1 noradrenoceptor activation increases motoneuron responsiveness to excitatory glutamate (AMPA) receptor-mediated inputs during natural behaviour. We studied the effects of noradrenaline on AMPA receptor-mediated motor activity at the motoneuron level in freely behaving rats, particularly during rapid eye movement (REM) sleep, a period during which both AMPA receptor-triggered muscle twitches and periods of muscle quiescence in which AMPA drive is silent are exhibited. Male rats were subjected to electromyography and electroencephalography recording to monitor sleep and waking behaviour. The implantation of a cannula into the trigeminal motor nucleus of the brainstem allowed us to perfuse noradrenergic and glutamatergic drugs by reverse microdialysis, and thus to use masseter muscle activity as an index of motoneuronal output. We found that endogenous excitation of both α-1 noradrenoceptor and AMPA receptors during waking are coupled to motor activity; however, REM sleep exhibits an absence of endogenous α-1 noradrenoceptor activity. Importantly, exogenous α-1 noradrenoceptor stimulation cannot reverse the muscle twitch suppression induced by AMPA receptor blockade and nor can it elevate muscle activity during quiet REM, a phase when endogenous AMPA receptor activity is subthreshold. We conclude that the presence of an endogenous glutamatergic drive is necessary for noradrenaline to trigger muscle activity at the level of the motoneuron in an animal behaving naturally. PMID:24860176

From Bedlam to Decorum: Improving Lunchtime Behaviour

ERIC Educational Resources Information Center

Aviani, Robert

2006-01-01

In many middle schools, poor student lunchtime behaviour is an ongoing problem. Such behaviour can have a detrimental effect on a school's climate and culture, which can in turn degrade the quality of learning that occurs in the classroom. As a result, improving students' lunchtime behaviour should be a priority for staff. One solution is to make…

Electrical Characteristics of Organic Field Effect Transistor Formed by Gas Treatment of High-k Al2O3 at Low Temperature

NASA Astrophysics Data System (ADS)

Lee, Sunwoo; Yoon, Seungki; Park, In-Sung; Ahn, Jinho

2009-04-01

We studied the electrical characteristics of an organic field effect transistor (OFET) formed by the hydrogen (H2) and nitrogen (N2) mixed gas treatment of a gate dielectric layer. We also investigated how device mobility is related to the length and width variations of the channel. Aluminum oxide (Al2O3) was used as the gate dielectric layer. After the treatment, the mobility and subthreshold swing were observed to be significantly improved by the decreased hole carrier localization at the interfacial layer between the gate oxide and pentacene channel layers. H2 gas plays an important role in removing the defects of the gate oxide layer at temperatures below 100 °C.

Efficacy of interventions that use apps to improve diet, physical activity and sedentary behaviour: a systematic review.

PubMed

Schoeppe, Stephanie; Alley, Stephanie; Van Lippevelde, Wendy; Bray, Nicola A; Williams, Susan L; Duncan, Mitch J; Vandelanotte, Corneel

2016-12-07

Health and fitness applications (apps) have gained popularity in interventions to improve diet, physical activity and sedentary behaviours but their efficacy is unclear. This systematic review examined the efficacy of interventions that use apps to improve diet, physical activity and sedentary behaviour in children and adults. Systematic literature searches were conducted in five databases to identify papers published between 2006 and 2016. Studies were included if they used a smartphone app in an intervention to improve diet, physical activity and/or sedentary behaviour for prevention. Interventions could be stand-alone interventions using an app only, or multi-component interventions including an app as one of several intervention components. Outcomes measured were changes in the health behaviours and related health outcomes (i.e., fitness, body weight, blood pressure, glucose, cholesterol, quality of life). Study inclusion and methodological quality were independently assessed by two reviewers. Twenty-seven studies were included, most were randomised controlled trials (n = 19; 70%). Twenty-three studies targeted adults (17 showed significant health improvements) and four studies targeted children (two demonstrated significant health improvements). Twenty-one studies targeted physical activity (14 showed significant health improvements), 13 studies targeted diet (seven showed significant health improvements) and five studies targeted sedentary behaviour (two showed significant health improvements). More studies (n = 12; 63%) of those reporting significant effects detected between-group improvements in the health behaviour or related health outcomes, whilst fewer studies (n = 8; 42%) reported significant within-group improvements. A larger proportion of multi-component interventions (8 out of 13; 62%) showed significant between-group improvements compared to stand-alone app interventions (5 out of 14; 36%). Eleven studies reported app usage statistics, and three of them demonstrated that higher app usage was associated with improved health outcomes. This review provided modest evidence that app-based interventions to improve diet, physical activity and sedentary behaviours can be effective. Multi-component interventions appear to be more effective than stand-alone app interventions, however, this remains to be confirmed in controlled trials. Future research is needed on the optimal number and combination of app features, behaviour change techniques, and level of participant contact needed to maximise user engagement and intervention efficacy.

Subthreshold Schottky-barrier thin-film transistors with ultralow power and high intrinsic gain.

PubMed

Lee, Sungsik; Nathan, Arokia

2016-10-21

The quest for low power becomes highly compelling in newly emerging application areas related to wearable devices in the Internet of Things. Here, we report on a Schottky-barrier indium-gallium-zinc-oxide thin-film transistor operating in the deep subthreshold regime (i.e., near the OFF state) at low supply voltages (<1 volt) and ultralow power (<1 nanowatt). By using a Schottky-barrier at the source and drain contacts, the current-voltage characteristics of the transistor were virtually channel-length independent with an infinite output resistance. It exhibited high intrinsic gain (>400) that was both bias and geometry independent. The transistor reported here is useful for sensor interface circuits in wearable devices where high current sensitivity and ultralow power are vital for battery-less operation. Copyright © 2016, American Association for the Advancement of Science.

Economic costs of social phobia: a population-based study.

PubMed

Acarturk, C; Smit, Filip; de Graaf, R; van Straten, A; Ten Have, M; Cuijpers, P

2009-06-01

Information about the economic costs of social phobia is scant. In this study, we examine the economic costs of social phobia and subthreshold social phobia. Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS) which is a population-based prospective study (n=4,789). Costs related to health service uptake, patients' out-of-pocket expenses, and costs arising from production losses were calculated for the reference year 2003. The costs for people with social phobia were compared with the costs for people with no mental disorder. The annual per capita total costs of social phobia were euro 11,952 (95% CI=7,891-16,013) which is significantly higher than the total costs for people with no mental disorder, euro 2957 (95% CI=2690-3224). When adjusting for mental and somatic co-morbidity, the costs decreased to euro 6,100 (95% CI=2681-9519), or 136 million euro per year per 1 million inhabitants, which was still significantly higher than the costs for people with no mental disorder. The costs of subthreshold social phobia were also significantly higher than the costs for people without any mental disorder, at euro 4,687 (95% CI=2557-6816). The costs presented here are conservative lower estimates because we only included costs related to mental health services. The economic costs associated with social phobia are substantial, and those of subthreshold social phobia approach those of the full-blown disorder.

Non-linear Membrane Properties in Entorhinal Cortical Stellate Cells Reduce Modulation of Input-Output Responses by Voltage Fluctuations

PubMed Central

Fernandez, Fernando R.; Malerba, Paola; White, John A.

2015-01-01

The presence of voltage fluctuations arising from synaptic activity is a critical component in models of gain control, neuronal output gating, and spike rate coding. The degree to which individual neuronal input-output functions are modulated by voltage fluctuations, however, is not well established across different cortical areas. Additionally, the extent and mechanisms of input-output modulation through fluctuations have been explored largely in simplified models of spike generation, and with limited consideration for the role of non-linear and voltage-dependent membrane properties. To address these issues, we studied fluctuation-based modulation of input-output responses in medial entorhinal cortical (MEC) stellate cells of rats, which express strong sub-threshold non-linear membrane properties. Using in vitro recordings, dynamic clamp and modeling, we show that the modulation of input-output responses by random voltage fluctuations in stellate cells is significantly limited. In stellate cells, a voltage-dependent increase in membrane resistance at sub-threshold voltages mediated by Na+ conductance activation limits the ability of fluctuations to elicit spikes. Similarly, in exponential leaky integrate-and-fire models using a shallow voltage-dependence for the exponential term that matches stellate cell membrane properties, a low degree of fluctuation-based modulation of input-output responses can be attained. These results demonstrate that fluctuation-based modulation of input-output responses is not a universal feature of neurons and can be significantly limited by subthreshold voltage-gated conductances. PMID:25909971

Isotype InGaN/GaN heterobarrier diodes by ammonia molecular beam epitaxy

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

Fireman, Micha N.; Browne, David A.; Speck, James S.

The design of isotype InGaN/GaN heterobarrier diode structures grown by ammonia molecular beam epitaxy is presented. On the (0001) Ga-polar plane, a structure consisting of a surface n{sup +} GaN contact layer, followed by a thin InGaN layer, followed by a thick unintentionally doped (UID) GaN layer, and atop a buried n{sup +} GaN contact layer induces a large conduction band barrier via a depleted UID GaN layer. Suppression of reverse and subthreshold current in such isotype barrier devices under applied bias depends on the quality of this composite layer polarization. Sample series were grown under fixed InGaN growth conditionsmore » that varied either the UID GaN NH{sub 3} flow rate or the UID GaN thickness, and under fixed UID GaN growth conditions that varied InGaN growth conditions. Decreases in subthreshold current and reverse bias current were measured for thicker UID GaN layers and increasing InGaN growth rates. Temperature-dependent analysis indicated that although extracted barrier heights were lower than those predicted by 1D Schrödinger Poisson simulations (0.9 eV–1.4 eV for In compositions from 10% to 15%), optimized growth conditions increased the extracted barrier height from ∼11% to nearly 85% of the simulated values. Potential subthreshold mechanisms are discussed, along with those growth factors which might affect their prevalence.« less

Characterizing ISI and sub-threshold membrane potential distributions: Ensemble of IF neurons with random squared-noise intensity.

PubMed

Kumar, Sanjeev; Karmeshu

2018-04-01

A theoretical investigation is presented that characterizes the emerging sub-threshold membrane potential and inter-spike interval (ISI) distributions of an ensemble of IF neurons that group together and fire together. The squared-noise intensity σ 2 of the ensemble of neurons is treated as a random variable to account for the electrophysiological variations across population of nearly identical neurons. Employing superstatistical framework, both ISI distribution and sub-threshold membrane potential distribution of neuronal ensemble are obtained in terms of generalized K-distribution. The resulting distributions exhibit asymptotic behavior akin to stretched exponential family. Extensive simulations of the underlying SDE with random σ 2 are carried out. The results are found to be in excellent agreement with the analytical results. The analysis has been extended to cover the case corresponding to independent random fluctuations in drift in addition to random squared-noise intensity. The novelty of the proposed analytical investigation for the ensemble of IF neurons is that it yields closed form expressions of probability distributions in terms of generalized K-distribution. Based on a record of spiking activity of thousands of neurons, the findings of the proposed model are validated. The squared-noise intensity σ 2 of identified neurons from the data is found to follow gamma distribution. The proposed generalized K-distribution is found to be in excellent agreement with that of empirically obtained ISI distribution of neuronal ensemble. Copyright © 2018 Elsevier B.V. All rights reserved.

Photo-assisted etching of silicon in chlorine- and bromine-containing plasmas

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

Zhu, Weiye; Sridhar, Shyam; Liu, Lei

2014-05-28

Cl{sub 2}, Br{sub 2}, HBr, Br{sub 2}/Cl{sub 2}, and HBr/Cl{sub 2} feed gases diluted in Ar (50%–50% by volume) were used to study etching of p-type Si(100) in a rf inductively coupled, Faraday-shielded plasma, with a focus on the photo-assisted etching component. Etching rates were measured as a function of ion energy. Etching at ion energies below the threshold for ion-assisted etching was observed in all cases, with Br{sub 2}/Ar and HBr/Cl{sub 2}/Ar plasmas having the lowest and highest sub-threshold etching rates, respectively. Sub-threshold etching rates scaled with the product of surface halogen coverage (measured by X-ray photoelectron spectroscopy) andmore » Ar emission intensity (7504 Å). Etching rates measured under MgF{sub 2}, quartz, and opaque windows showed that sub-threshold etching is due to photon-stimulated processes on the surface, with vacuum ultraviolet photons being much more effective than longer wavelengths. Scanning electron and atomic force microscopy revealed that photo-etched surfaces were very rough, quite likely due to the inability of the photo-assisted process to remove contaminants from the surface. Photo-assisted etching in Cl{sub 2}/Ar plasmas resulted in the formation of 4-sided pyramidal features with bases that formed an angle of 45° with respect to 〈110〉 cleavage planes, suggesting that photo-assisted etching can be sensitive to crystal orientation.« less

Coincidence-enhanced stochastic resonance: experimental evidence challenges the psychophysical theory behind stochastic resonance.

PubMed

Perez, Claudio A; Cohn, Theodore E; Medina, Leonel E; Donoso, José R

2007-08-31

Stochastic resonance (SR) is the counterintuitive phenomenon in which noise enhances detection of sub-threshold stimuli. The SR psychophysical threshold theory establishes that the required amplitude to exceed the sensory threshold barrier can be reached by adding noise to a sub-threshold stimulus. The aim of this study was to test the SR theory by comparing detection results from two different randomly-presented stimulus conditions. In the first condition, optimal noise was present during the whole attention interval; in the second, the optimal noise was restricted to the same time interval as the stimulus. SR threshold theory predicts no difference between the two conditions because noise helps the sub-threshold stimulus to reach threshold in both cases. The psychophysical experimental method used a 300 ms rectangular force pulse as a stimulus within an attention interval of 1.5 s, applied to the index finger of six human subjects in the two distinct conditions. For all subjects we show that in the condition in which the noise was present only when synchronized with the stimulus, detection was better (p<0.05) than in the condition in which the noise was delivered throughout the attention interval. These results provide the first direct evidence that SR threshold theory is incomplete and that a new phenomenon has been identified, which we call Coincidence-Enhanced Stochastic Resonance (CESR). We propose that CESR might occur because subject uncertainty is reduced when noise points at the same temporal window as the stimulus.

Ultra-sensitive suspended atomically thin-layered black phosphorus mercury sensors.

PubMed

Li, Peng; Zhang, Dongzhi; Jiang, Chuanxing; Zong, Xiaoqi; Cao, Yuhua

2017-12-15

The extraordinary properties of black phosphorus (BP) make it a promising candidate for next-generation transistor chemical sensors. However, BP films reported so far are supported on substrate, and substrate scattering drastically deteriorates its electrical properties. Consequentially, the potential sensing capability of intrinsic BP is highly underestimated and its sensing mechanism is masked. Additionally, the optimum sensing regime of BP remains unexplored. This article is the first demonstration of suspended BP sensor operated in subthreshold regime. BP exhibited significant enhancement of sensitivity for ultra-low-concentration mercury detection in the absence of substrate, and the sensitivity reached maximum in subthreshold regime. Without substrate scattering, the suspended BP device demonstrated 10 times lower 1/f noise which contributed to better signal-to-noise ratio. Therefore, rapid label-free trace detection of Hg 2+ was achieved with detection limit of 0.01 ppb, lower than the world health organization (WHO) tolerance level (1 ppb). The time constant for ion detection extracted was 3s. Additionally, experimental results revealed that good stability, repeatability, and selectivity were achieved. BP sensors also demonstrated the ability of detecting mercury ions in environment water samples. The underling sensing mechanism of intrinsic BP was ascribed to the carrier density variation resulted from surface charge gating effect, so suspended BP in subthreshold regime with optimum gating effect demonstrated the best sensitivity. Our results show the prominent advantages of intrinsic BP as a sensing material. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Non-linear Membrane Properties in Entorhinal Cortical Stellate Cells Reduce Modulation of Input-Output Responses by Voltage Fluctuations.

PubMed

Fernandez, Fernando R; Malerba, Paola; White, John A

2015-04-01

The presence of voltage fluctuations arising from synaptic activity is a critical component in models of gain control, neuronal output gating, and spike rate coding. The degree to which individual neuronal input-output functions are modulated by voltage fluctuations, however, is not well established across different cortical areas. Additionally, the extent and mechanisms of input-output modulation through fluctuations have been explored largely in simplified models of spike generation, and with limited consideration for the role of non-linear and voltage-dependent membrane properties. To address these issues, we studied fluctuation-based modulation of input-output responses in medial entorhinal cortical (MEC) stellate cells of rats, which express strong sub-threshold non-linear membrane properties. Using in vitro recordings, dynamic clamp and modeling, we show that the modulation of input-output responses by random voltage fluctuations in stellate cells is significantly limited. In stellate cells, a voltage-dependent increase in membrane resistance at sub-threshold voltages mediated by Na+ conductance activation limits the ability of fluctuations to elicit spikes. Similarly, in exponential leaky integrate-and-fire models using a shallow voltage-dependence for the exponential term that matches stellate cell membrane properties, a low degree of fluctuation-based modulation of input-output responses can be attained. These results demonstrate that fluctuation-based modulation of input-output responses is not a universal feature of neurons and can be significantly limited by subthreshold voltage-gated conductances.

Exact subthreshold integration with continuous spike times in discrete-time neural network simulations.

PubMed

Morrison, Abigail; Straube, Sirko; Plesser, Hans Ekkehard; Diesmann, Markus

2007-01-01

Very large networks of spiking neurons can be simulated efficiently in parallel under the constraint that spike times are bound to an equidistant time grid. Within this scheme, the subthreshold dynamics of a wide class of integrate-and-fire-type neuron models can be integrated exactly from one grid point to the next. However, the loss in accuracy caused by restricting spike times to the grid can have undesirable consequences, which has led to interest in interpolating spike times between the grid points to retrieve an adequate representation of network dynamics. We demonstrate that the exact integration scheme can be combined naturally with off-grid spike events found by interpolation. We show that by exploiting the existence of a minimal synaptic propagation delay, the need for a central event queue is removed, so that the precision of event-driven simulation on the level of single neurons is combined with the efficiency of time-driven global scheduling. Further, for neuron models with linear subthreshold dynamics, even local event queuing can be avoided, resulting in much greater efficiency on the single-neuron level. These ideas are exemplified by two implementations of a widely used neuron model. We present a measure for the efficiency of network simulations in terms of their integration error and show that for a wide range of input spike rates, the novel techniques we present are both more accurate and faster than standard techniques.

A search for the production of direct leptons in nucleon-nucleus and nucleus-nucleus collisions

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

Kirk, P.N.

1990-12-01

This report discusses the following topics: subthreshold production experiment; testing and selection of PCOS amplifiers; transverse energy detector; development of a sensitive new amplifiers; single-lepton experiment. (LSP)

Value for money of changing healthcare services? Economic evaluation of quality improvement

PubMed Central

Severens, J

2003-01-01



 There are many instances of perceived or real inefficiencies in health service delivery. Both healthcare providers and policy makers need to know the impact and cost of applying strategies to change the behaviour of individuals or organisations. Quality improvement or implementation research is concerned with evaluating the methods of behavioural change. Addressing inefficiencies in healthcare services raises a series of issues, beginning with how inefficiency itself should be defined. The basic concepts of cost analysis and economic evaluations are explained and a model for working through the economic issues of quality improvement is discussed. This model combines the costs and benefits of corrected inefficiency with the costs and degree of behavioural change achieved by a quality improvement method in the policy maker's locality. It shows why it may not always be cost effective for policy makers to address suboptimal behaviour. Both the interpretation of quality improvement research findings and their local application need careful consideration. The limited availability of applicable quality improvement research may make it difficult to provide robust advice on the value for money of many behavioural quality improvement strategies. PMID:14532369

Joint estimation over multiple individuals improves behavioural state inference from animal movement data.

PubMed

Jonsen, Ian

2016-02-08

State-space models provide a powerful way to scale up inference of movement behaviours from individuals to populations when the inference is made across multiple individuals. Here, I show how a joint estimation approach that assumes individuals share identical movement parameters can lead to improved inference of behavioural states associated with different movement processes. I use simulated movement paths with known behavioural states to compare estimation error between nonhierarchical and joint estimation formulations of an otherwise identical state-space model. Behavioural state estimation error was strongly affected by the degree of similarity between movement patterns characterising the behavioural states, with less error when movements were strongly dissimilar between states. The joint estimation model improved behavioural state estimation relative to the nonhierarchical model for simulated data with heavy-tailed Argos location errors. When applied to Argos telemetry datasets from 10 Weddell seals, the nonhierarchical model estimated highly uncertain behavioural state switching probabilities for most individuals whereas the joint estimation model yielded substantially less uncertainty. The joint estimation model better resolved the behavioural state sequences across all seals. Hierarchical or joint estimation models should be the preferred choice for estimating behavioural states from animal movement data, especially when location data are error-prone.

Improved confidence in performing nutrition and physical activity behaviours mediates behavioural change in young adults: Mediation results of a randomised controlled mHealth intervention.

PubMed

Partridge, Stephanie R; McGeechan, Kevin; Bauman, Adrian; Phongsavan, Philayrath; Allman-Farinelli, Margaret

2017-01-01

The burden of weight gain disproportionally affects young adults. Understanding the underlying behavioural mechanisms of change in mHealth nutrition and physical activity interventions designed for young adults is important for enhancing and translating effective interventions. First, we hypothesised that knowledge, self-efficacy and stage-of-change for nutrition and physical activity behaviours would improve, and second, that self-efficacy changes in nutrition and physical activity behaviours mediate the behaviour changes observed in an mHealth RCT for prevention of weight gain. Young adults, aged 18-35 years at risk of weight gain (n = 250) were randomly assigned to an mHealth-program, TXT2BFiT, consisting of a three-month intensive phase and six-month maintenance phase or to a control group. Self-reported online surveys at baseline, three- and nine-months assessed nutrition and physical activity behaviours, knowledge, self-efficacy and stage-of-change. The mediating effect of self-efficacy was assessed in multiple PROCESS macro-models for three- and nine-month nutrition and physical activity behaviour change. Young adults randomised to the intervention increased and maintained knowledge of fruit requirements (P = 0.029) compared to controls. Intervention participants' fruit and takeaway behaviours improved to meet recommendations at nine months, with a greater proportion progressing to action or maintenance stage-of-change (P < 0.001 and P = 0.012 respectively) compared to controls. Intervention participants' vegetable and physical activity behaviours did not meet recommendations, thereby halting progress to action or maintenance stage-of-change. Indirect effects of improved nutrition and physical activity behaviours at three- and nine-months in the intervention group were explained by changes in self-efficacy, accounting for 8%-37% of the total effect. This provides insights into how the mHealth intervention achieved part of its effects and the importance of improving self-efficacy to facilitate improved eating and physical activity behaviours in young adults. Copyright © 2016 Elsevier Ltd. All rights reserved.

Balanced: a randomised trial examining the efficacy of two self-monitoring methods for an app-based multi-behaviour intervention to improve physical activity, sitting and sleep in adults.

PubMed

Duncan, Mitch J; Vandelanotte, Corneel; Trost, Stewart G; Rebar, Amanda L; Rogers, Naomi; Burton, Nicola W; Murawski, Beatrice; Rayward, Anna; Fenton, Sasha; Brown, Wendy J

2016-07-30

Many adults are insufficiently physically active, have prolonged sedentary behaviour and report poor sleep. These behaviours can be improved by interventions that include education, goal setting, self-monitoring, and feedback strategies. Few interventions have explicitly targeted these behaviours simultaneously or examined the relative efficacy of different self-monitoring methods. This study aims to compare the efficacy of two self-monitoring methods in an app-based multi-behaviour intervention to improve objectively measured physical activity, sedentary, and sleep behaviours, in a 9 week 2-arm randomised trial. Participants will be adults (n = 64) who report being physically inactive, sitting >8 h/day and frequent insufficient sleep (≥14 days out of last 30). The "Balanced" intervention is delivered via a smartphone 'app', and includes education materials (guidelines, strategies to promote change in behaviour), goal setting, self-monitoring and feedback support. Participants will be randomly allocated to either a device-entered or user-entered self-monitoring method. The device-entered group will be provided with a activity tracker to self-monitor behaviours. The user-entered group will recall and manually record behaviours. Assessments will be conducted at 0, 3, 6, and 9 weeks. Physical activity, sedentary behaviour and sleep-wake behaviours will be measured using the wrist worn Geneactiv accelerometer. Linear mixed models will be used to examine differences between groups and over time using an alpha of 0.01. This study will evaluate an app-based multi-behavioural intervention to improve physical activity, sedentary behaviour and sleep; and the relative efficacy of two different approaches to self-monitoring these behaviours. Outcomes will provide information to inform future interventions and self-monitoring targeting these behaviours. ACTRN12615000182594 (Australian New Zealand Clinical Trials Registry. Registry URL: www.anzctr.org.au ; registered prospectively on 25 February 2015).

A critical role of striatal A2A R-mGlu5 R interactions in modulating the psychomotor and drug-seeking effects of methamphetamine.

PubMed

Wright, Sherie R; Zanos, Panos; Georgiou, Polymnia; Yoo, Ji-Hoon; Ledent, Catherine; Hourani, Susanna M; Kitchen, Ian; Winsky-Sommerer, Raphaelle; Bailey, Alexis

2016-07-01

Addiction to psychostimulants is a major public health problem with no available treatment. Adenosine A2A receptors (A2A R) co-localize with metabotropic glutamate 5 receptors (mGlu5 R) in the striatum and functionally interact to modulate behaviours induced by addictive substances, such as alcohol. Using genetic and pharmacological antagonism of A2A R in mice, we investigated whether A2A R-mGlu5 R interaction can regulate the locomotor, stereotypic and drug-seeking effect of methamphetamine and cocaine, two drugs that exhibit distinct mechanism of action. Genetic deletion of A2A R, as well as combined administration of sub-threshold doses of the selective A2A R antagonist (SCH 58261, 0.01 mg/kg, i.p.) with the mGlu5 R antagonist, 3-((2-methyl-4-thiazolyl)ethynyl)pyridine (0.01 mg/kg, i.p.), prevented methamphetamine- but not cocaine-induced hyperactivity and stereotypic rearing behaviour. This drug combination also prevented methamphetamine-rewarding effects in a conditioned-place preference paradigm. Moreover, mGlu5 R binding was reduced in the nucleus accumbens core of A2A R knockout (KO) mice supporting an interaction between these receptors in a brain region crucial in mediating addiction processes. Chronic methamphetamine, but not cocaine administration, resulted in a significant increase in striatal mGlu5 R binding in wild-type mice, which was absent in the A2A R KO mice. These data are in support of a critical role of striatal A2A R-mGlu5 R functional interaction in mediating the ambulatory, stereotypic and reinforcing effects of methamphetamine but not cocaine-induced hyperlocomotion or stereotypy. The present study highlights a distinct and selective mechanistic role for this receptor interaction in regulating methamphetamine-induced behaviours and suggests that combined antagonism of A2A R and mGlu5 R may represent a novel therapy for methamphetamine addiction. © 2015 Society for the Study of Addiction.

A randomised controlled trial of a theory-based intervention to improve sun protective behaviour in adolescents ('you can still be HOT in the shade'): study protocol.

PubMed

Hawkes, Anna L; Hamilton, Kyra; White, Katherine M; McD Young, Ross

2012-01-03

Most skin cancers are preventable by encouraging consistent use of sun protective behaviour. In Australia, adolescents have high levels of knowledge and awareness of the risks of skin cancer but exhibit significantly lower sun protection behaviours than adults. There is limited research aimed at understanding why people do or do not engage in sun protective behaviour, and an associated absence of theory-based interventions to improve sun safe behaviour. This paper presents the study protocol for a school-based intervention which aims to improve the sun safe behaviour of adolescents. Approximately 400 adolescents (aged 12-17 years) will be recruited through Queensland, Australia public and private schools and randomized to the intervention (n = 200) or 'wait-list' control group (n = 200). The intervention focuses on encouraging supportive sun protective attitudes and beliefs, fostering perceptions of normative support for sun protection behaviour, and increasing perceptions of control/self-efficacy over using sun protection. It will be delivered during three × one hour sessions over a three week period from a trained facilitator during class time. Data will be collected one week pre-intervention (Time 1), and at one week (Time 2) and four weeks (Time 3) post-intervention. Primary outcomes are intentions to sun protect and sun protection behaviour. Secondary outcomes include attitudes toward performing sun protective behaviours (i.e., attitudes), perceptions of normative support to sun protect (i.e., subjective norms, group norms, and image norms), and perceived control over performing sun protective behaviours (i.e., perceived behavioural control). The study will provide valuable information about the effectiveness of the intervention in improving the sun protective behaviour of adolescents. © 2011 Hawkes et al; licensee BioMed Central Ltd.

Low Temperature Noise and Electrical Characterization of the Company Heterojunction Field-Effect Transistor

NASA Technical Reports Server (NTRS)

Cunningham, Thomas J.; Gee, Russell C.; Fossum, Eric R.; Baier, Steven M.

1993-01-01

This paper discusses the electrical properties of the complementary heterojunction field-effect transistor (CHFET) at 4K, including the gate leakage current, the subthreshold transconductance, and the input-referred noise voltage.

Multi-electrode array technologies for neuroscience and cardiology

NASA Astrophysics Data System (ADS)

Spira, Micha E.; Hai, Aviad

2013-02-01

At present, the prime methodology for studying neuronal circuit-connectivity, physiology and pathology under in vitro or in vivo conditions is by using substrate-integrated microelectrode arrays. Although this methodology permits simultaneous, cell-non-invasive, long-term recordings of extracellular field potentials generated by action potentials, it is 'blind' to subthreshold synaptic potentials generated by single cells. On the other hand, intracellular recordings of the full electrophysiological repertoire (subthreshold synaptic potentials, membrane oscillations and action potentials) are, at present, obtained only by sharp or patch microelectrodes. These, however, are limited to single cells at a time and for short durations. Recently a number of laboratories began to merge the advantages of extracellular microelectrode arrays and intracellular microelectrodes. This Review describes the novel approaches, identifying their strengths and limitations from the point of view of the end users -- with the intention to help steer the bioengineering efforts towards the needs of brain-circuit research.

Multi-electrode array technologies for neuroscience and cardiology.

PubMed

Spira, Micha E; Hai, Aviad

2013-02-01

At present, the prime methodology for studying neuronal circuit-connectivity, physiology and pathology under in vitro or in vivo conditions is by using substrate-integrated microelectrode arrays. Although this methodology permits simultaneous, cell-non-invasive, long-term recordings of extracellular field potentials generated by action potentials, it is 'blind' to subthreshold synaptic potentials generated by single cells. On the other hand, intracellular recordings of the full electrophysiological repertoire (subthreshold synaptic potentials, membrane oscillations and action potentials) are, at present, obtained only by sharp or patch microelectrodes. These, however, are limited to single cells at a time and for short durations. Recently a number of laboratories began to merge the advantages of extracellular microelectrode arrays and intracellular microelectrodes. This Review describes the novel approaches, identifying their strengths and limitations from the point of view of the end users--with the intention to help steer the bioengineering efforts towards the needs of brain-circuit research.

Taste-aversion learning produced by combined treatment with subthreshold radiation and lithium chloride

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

Rabin, B.M.; Hunt, W.A.; Lee, J.

1987-01-01

These experiments were designed to determine whether treatment with two subthreshold doses of radiation or lithium chloride, either alone or in combination, could lead to taste-aversion learning. The first experiment determined the threshold for a radiation-induced taste aversion at 15-20 rad and for lithium chloride at 0.30-0.45 mEq/kg. In the second experiment it was shown that exposing rats to two doses of 15 rad separated by up to 3 hr produced a taste aversion. Treatment with two injections of lithium chloride did produce a taste aversion when the two treatments were administered within 1 hr or each other. The resultsmore » are discussed in terms of the implications of these findings for understanding the nature of the unconditional stimuli leading to the acquisition of a conditioned taste aversion.« less

Experimental study of firing death in a network of chaotic FitzHugh-Nagumo neurons

NASA Astrophysics Data System (ADS)

Ciszak, Marzena; Euzzor, Stefano; Arecchi, F. Tito; Meucci, Riccardo

2013-02-01

The FitzHugh-Nagumo neurons driven by a periodic forcing undergo a period-doubling route to chaos and a transition to mixed-mode oscillations. When coupled, their dynamics tend to be synchronized. We show that the chaotically spiking neurons change their internal dynamics to subthreshold oscillations, the phenomenon referred to as firing death. These dynamical changes are observed below the critical coupling strength at which the transition to full chaotic synchronization occurs. Moreover, we find various dynamical regimes in the subthreshold oscillations, namely, regular, quasiperiodic, and chaotic states. We show numerically that these dynamical states may coexist with large-amplitude spiking regimes and that this coexistence is characterized by riddled basins of attraction. The reported results are obtained for neurons implemented in the electronic circuits as well as for the model equations. Finally, we comment on the possible scenarios where the coupling-induced firing death could play an important role in biological systems.

Unexpected subthreshold autism spectrum in a 25-year-old male stalker hospitalized for delusional disorder: a case report.

PubMed

Dell'Osso, Liliana; Dalle Luche, Riccardo; Cerliani, Corrado; Bertelloni, Carlo Antonio; Gesi, Camilla; Carmassi, Claudia

2015-08-01

This paper highlights the clinical challenges faced when assessing patients with stalking behaviors with psychotic disorders, suggesting the need for an accurate assessment of adult autism spectrum symptoms. A 25-year-old man with a diagnosis of delusional disorder, erotomanic type, was hospitalized for acute psychotic symptoms occurred in the framework of a repeated stalking behavior towards his ex girlfriend. When assessed for adult autism spectrum symptoms upon an accurate clinical evaluation, he reported elevated scores in the mentalizing deficit and social anxiety domains by means of the 14 item Ritvo Autism and Asperger Diagnostic Scale (RAADS-14). Authors discuss a possible role of adult (subthreshold) autism spectrum symptoms, generally disregarded in adult psychiatry, on the type of psychotic features and stalking behavior developed that may help for appropriate diagnosis and treatment. Copyright © 2015 Elsevier Inc. All rights reserved.

Psychotropic marketing practices and problems: implications for DSM-5.

PubMed

Raven, Melissa; Parry, Peter

2012-06-01

The descriptive diagnostic model since DSM-III has often led to "cookbook" diagnosis and assumptions of "chemical imbalance" for psychiatric disorders. Pharmaceutical companies have exploited this in their marketing. This includes promoting self-diagnosis with online checklists. Significant overprescribing of psychotropics has resulted. DSM-5 will provide new disorders and broader diagnostic criteria that will likely exacerbate this. Most psychotropic prescribing is done by primary care physicians, who are problematically excluded from DSM-5 field trials and are influenced by industry funded key opinion leaders who may promote diagnosis of subthreshold cases. More lax criteria will increase diagnosis of subthreshold cases. Expansion of not otherwise specified (NOS) categories can be used to justify off-label promotion. Pediatric bipolar disorder, constructed within the bipolar disorder NOS category, became an "epidemic" in the United States, fuelled by diagnostic upcoding pressures. Disruptive mood dysregulation disorder may similarly cause overdiagnosis and excessive prescribing, as will other new disorders and lower diagnostic thresholds.

Micropulsed diode laser therapy: evolution and clinical applications.

PubMed

Sivaprasad, Sobha; Elagouz, Mohammed; McHugh, Dominic; Shona, Olajumoke; Dorin, Giorgio

2010-01-01

Many clinical trials have demonstrated the clinical efficacy of laser photocoagulation in the treatment of retinal vascular diseases, including diabetic retinopathy. There is, however, collateral iatrogenic retinal damage and functional loss after conventional laser treatment. Such side effects may occur even when the treatment is appropriately performed because of morphological damage caused by the visible endpoint, typically a whitening burn. The development of the diode laser with micropulsed emission has allowed subthreshold therapy without a visible burn endpoint. This greatly reduces the risk of structural and functional retinal damage, while retaining the therapeutic efficacy of conventional laser treatment. Studies using subthreshold micropulse laser protocols have reported successful outcomes for diabetic macular edema, central serous chorioretinopathy, macular edema secondary to retinal vein occlusion, and primary open angle glaucoma. The report includes the rationale and basic principles underlying micropulse diode laser therapy, together with a review of its current clinical applications. Copyright © 2010 Elsevier Inc. All rights reserved.

A Self-Aligned InGaAs Quantum-Well Metal-Oxide-Semiconductor Field-Effect Transistor Fabricated through a Lift-Off-Free Front-End Process

NASA Astrophysics Data System (ADS)

Lin, Jianqiang; Kim, Tae-Woo; Antoniadis, Dimitri A.; del Alamo, Jesús A.

2012-06-01

We present a novel n-type InGaAs quantum-well metal-oxide-semiconductor field-effect transistor (QW-MOSFET) fabricated by a self-aligned gate-last process and investigate relevant Si-like manufacturing issues in future III-V MOSFETs. The device structure features a composite InP/Al2O3 gate barrier with a capacitance equivalent thickness (CET) of 3 nm and non alloyed Mo ohmic contacts. We have found that RIE introduces significant damage to the intrinsic device resulting in poor current drive and subthreshold swing. The effect is largely removed through a thermal annealing step. Thermally annealed QW-MOSFETs exhibit a subthreshold swing of 95 mV/dec, indicative of excellent interfacial characteristics. The peak mobility of the MOSFET is 2780 cm2 V-1 s-1.

Optimizing MOS-gated thyristor using voltage-based equivalent circuit model for designing steep-subthreshold-slope PN-body-tied silicon-on-insulator FET

NASA Astrophysics Data System (ADS)

Ueda, Daiki; Takeuchi, Kiyoshi; Kobayashi, Masaharu; Hiramoto, Toshiro

2018-04-01

A new circuit model that provides a clear guide on designing a MOS-gated thyristor (MGT) is reported. MGT plays a significant role in achieving a steep subthreshold slope of a PN-body tied silicon-on-insulator (SOI) FET (PNBTFET), which is an SOI MOSFET merged with an MGT. The effects of design parameters on MGT and the proposed equivalent circuit model are examined to determine how to regulate the voltage response of MGT and how to suppress power dissipation. It is demonstrated that MGT with low threshold voltages, small hysteresis widths, and small power dissipation can be designed by tuning design parameters. The temperature dependence of MGT is also examined, and it is confirmed that hysteresis width decreases with the average threshold voltage kept nearly constant as temperature rises. The equivalent circuit model can be conveniently used to design low-power PNBTFET.

Two dimensional analytical model for a reconfigurable field effect transistor

NASA Astrophysics Data System (ADS)

Ranjith, R.; Jayachandran, Remya; Suja, K. J.; Komaragiri, Rama S.

2018-02-01

This paper presents two-dimensional potential and current models for a reconfigurable field effect transistor (RFET). Two potential models which describe subthreshold and above-threshold channel potentials are developed by solving two-dimensional (2D) Poisson's equation. In the first potential model, 2D Poisson's equation is solved by considering constant/zero charge density in the channel region of the device to get the subthreshold potential characteristics. In the second model, accumulation charge density is considered to get above-threshold potential characteristics of the device. The proposed models are applicable for the device having lightly doped or intrinsic channel. While obtaining the mathematical model, whole body area is divided into two regions: gated region and un-gated region. The analytical models are compared with technology computer-aided design (TCAD) simulation results and are in complete agreement for different lengths of the gated regions as well as at various supply voltage levels.

Prevalence and predictors of pathological gambling: results from the St. Louis personality, health and lifestyle (SLPHL) study

PubMed Central

Cunningham-Williams, Renee M.; Grucza, Richard A.; Cottler, Linda B.; Womack, Sharon B.; Books, Samantha J.; Przybeck, Thomas R.; Spitznagel, Edward L.; Cloninger, C. Robert

2006-01-01

Objectives We report the prevalence of and risk and protective factors for DSM-IV sub-threshold gambling (1–4 criteria) and pathological gambling disorder (PGD; 5–10 criteria) in a non-clinical household sample of St. Louis area gamblers. Methods Of the 7689 individuals contacted via Random Digit Dialing, 3292 were screened eligible. Of these, 1142 from households in 6 contiguous regions in Missouri and Illinois consented to participate and were mailed a St. Louis Area Personality, Health, and Lifestyle (SLPHL) Survey. Results Post-stratification weighted data (n = 913) indicate lifetime prevalence rates of 12.4% sub-threshold and 2.5% PGD (conditional prevalence = 21.5% and 4.3% respectively). Risk and protective factors for gambling severity varied in the sample. Conclusions Targeted prevention messages are warranted specifically for gamblers of varying risk for PGD. PMID:15804388

Molecular physiology and modulation of somatodendritic A-type potassium channels.

PubMed

Jerng, Henry H; Pfaffinger, Paul J; Covarrubias, Manuel

2004-12-01

The somatodendritic subthreshold A-type K+ current (ISA) in nerve cells is a critical component of the ensemble of voltage-gated ionic currents that determine somatodendritic signal integration. The underlying K+ channel belongs to the Shal subfamily of voltage-gated K+ channels. Most Shal channels across the animal kingdom share a high degree of structural conservation, operate in the subthreshold range of membrane potentials, and exhibit relatively fast inactivation and recovery from inactivation. Mammalian Shal K+ channels (Kv4) undergo preferential closed-state inactivation with features that are generally inconsistent with the classical mechanisms of inactivation typical of Shaker K+ channels. Here, we review (1) the physiological and genetic properties of ISA, 2 the molecular mechanisms of Kv4 inactivation and its remodeling by a family of soluble calcium-binding proteins (KChIPs) and a membrane-bound dipeptidase-like protein (DPPX), and (3) the modulation of Kv4 channels by protein phosphorylation.

A room temperature process for the fabrication of amorphous indium gallium zinc oxide thin-film transistors with co-sputtered Zr x Si1- x O2 Gate dielectric and improved electrical and hysteresis performance

NASA Astrophysics Data System (ADS)

Hung, Chien-Hsiung; Wang, Shui-Jinn; Liu, Pang-Yi; Wu, Chien-Hung; Wu, Nai-Sheng; Yan, Hao-Ping; Lin, Tseng-Hsing

2017-04-01

The use of co-sputtered zirconium silicon oxide (Zr x Si1- x O2) gate dielectrics to improve the gate controllability of amorphous indium gallium zinc oxide (α-IGZO) thin-film transistors (TFTs) through a room-temperature fabrication process is proposed and demonstrated. With the sputtering power of the SiO2 target in the range of 0-150 W and with that of the ZrO2 target kept at 100 W, a dielectric constant ranging from approximately 28.1 to 7.8 is obtained. The poly-structure formation immunity of the Zr x Si1- x O2 dielectrics, reduction of the interface trap density suppression, and gate leakage current are examined. Our experimental results reveal that the Zr0.85Si0.15O2 gate dielectric can lead to significantly improved TFT subthreshold swing performance (103 mV/dec) and field effect mobility (33.76 cm2 V-1 s-1).

The experiences of women of reproductive age regarding health-promoting behaviours: A qualitative study

PubMed Central

2012-01-01

Background Health promotion is critical for community and family health. Health-promoting behaviours provide solutions for maintaining and promoting health. Although several studies have addressed the frequency and different types of health-promoting behaviours in women, little information is available about their experiences. This study aimed to explore the experiences of women of reproductive age regarding health-promoting behaviours. Methods In the present study, which was conducted in Tehran, Iran, 15 females, who were selected purposefully, participated in individual in-depth, semi-structured interviews. The interviews were recorded, transcribed verbatim, and analysed using conventional content analysis. Results Nine main categories were derived from the analysis, including establishing an appropriate eating pattern, establishing a balanced rest/activity pattern, spirituality, stress management, personal sensitivity and responsibility, establishing an appropriate pattern of social interactions, practicing safe and healthy recreations, feeling improvement in physical-functional health, and feeling improvement in emotional and psychological health. The first 7 categories represent the nature and types of real health-promoting behaviours in women of reproductive age, whereas the last 2 constitute feeling and understanding of the implementation of these behaviours. Conclusion The study findings show that the women experience improvement in physical-functional, emotional, and psychological health by implementing health-promoting behaviours. It is therefore necessary to introduce strategies in the context of the community culture for improving different aspects of health-promoting behaviours in women of reproductive age to maintain and improve their overall health. PMID:22846587

The Development of III-V Semiconductor MOSFETs for Future CMOS Applications

NASA Astrophysics Data System (ADS)

Greene, Andrew M.

Alternative channel materials with superior transport properties over conventional strained silicon are required for supply voltage scaling in low power complementary metal-oxide-semiconductor (CMOS) integrated circuits. Group III-V compound semiconductor systems offer a potential solution due to their high carrier mobility, low carrier effective mass and large injection velocity. The enhancement in transistor drive current at a lower overdrive voltage allows for the scaling of supply voltage while maintaining high switching performance. This thesis focuses on overcoming several material and processing challenges associated with III-V semiconductor development including a low thermal processing budget, high interface trap state density (Dit), low resistance source/drain contacts and growth on lattice mismatched substrates. Non-planar In0.53Ga0.47As FinFETs were developed using both "gate-first" and "gate-last" fabrication methods for n-channel MOSFETs. Electron beam lithography and anisotropic plasma etching processes were optimized to create highly scaled fins with near vertical sidewalls. Plasma damage was removed using a wet etch process and improvements in gate efficiency were characterized on MOS capacitor structures. A two-step, selective removal of the pre-grown n+ contact layer was developed for "gate-last" recess etching. The final In0.53Ga 0.47As FinFET devices demonstrated an ION = 70 mA/mm, I ON/IOFF ratio = 15,700 and sub-threshold swing = 210 mV/dec. Bulk GaSb and strained In0.36Ga0.64Sb quantum well (QW) heterostructures were developed for p-channel MOSFETs. Dit was reduced to 2 - 3 x 1012 cm-2eV-1 using an InAs surface layer, (NH4)2S passivation and atomic layer deposition (ALD) of Al2O3. A self-aligned "gate-first" In0.36Ga0.64Sb MOSFET fabrication process was invented using a "T-shaped" electron beam resist patterning stack and intermetallic source/drain contacts. Ni contacts annealed at 300°C demonstrated an ION = 166 mA/mm, ION/IOFF ratio = 1,500 and sub-threshold swing = 340 mV/dec. Split C-V measurements were used to extract an effective channel mobility of muh* = 300 cm2/Vs at Ns = 2 x 1012 cm -2. "Gate-last" MOSFETs grown with an epitaxial p + contact layer were fabricated using selective gate-recess etching techniques. A parasitic "n-channel" limited ION/I OFF ratio and sub-threshold swing, most likely due to effects from the InAs surface layer.

Associations of eHealth literacy with health-promoting behaviours among hospital nurses: A descriptive cross-sectional study.

PubMed

Cho, Hyeonmi; Han, Kihye; Park, Bu Kyung

2018-07-01

To investigate the associations of eHealth Literacy with health-promoting behaviours among hospital nurses in South Korea. Health-promoting behaviours of nurses are crucial for their own improved health and health-related behaviours of patients. eHealth literacy refers to the ability to search, understand and evaluate health information available online. With the growing use of the Internet, eHealth literacy is emerging as an important factor enhancing health-promoting behaviours. Descriptive cross-sectional design with self-reported questionnaires. Data were collected between March-May 2016 from five hospitals in South Korea. Health-promoting behaviours and eHealth literacy were assessed using Health Promoting Lifestyle Profile-II and K-eHEALS, respectively. Multiple linear regression models were used to examine the associations of eHealth literacy and health-promoting behaviours. Nurses with high level of eHealth literacy had significantly positive overall health-promoting behaviours, stress management, interpersonal relations, self-actualization and health responsibility, but not for nutrition and physical activity. Improving eHealth literacy through various strategies could be an effective way to boost health-promoting behaviours among nurses. However, improvement of actual health-promoting behaviours such as nutrition and physical activity will require systematic and organizational changes. © 2018 John Wiley & Sons Ltd.

Features of hypochondriasis and illness worry in the general population in Germany.

PubMed

Martin, Alexandra; Jacobi, Frank

2006-01-01

Although hypochondriasis is considered to be of high relevance in the healthcare sector, its prevalence in the general population has been investigated in few studies. The aims of this study were to estimate prevalence rates of hypochondriasis and of subthreshold conditions and to describe their associated features such as quality of life and healthcare utilization in a representative community sample. Analyses of the present study are based on the German Health Interview and Examination Survey-Mental Health Supplement (N = 4181, representative for the German population from 18-65 years). The assessment included interviews for somatic conditions and mental disorders and self-report ratings on health-related quality of life, healthcare utilization, disability days, and physical activity. Only three cases (0.05%) were identified as meeting full criteria of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) hypochondriasis. The prevalence rate of the less restrictively defined form of hypochondriasis, ("subthreshold hypochondriasis") was 0.58% and an additional 2.12% reported having had illness worries for at least 6 months but did not meet further hypochondriasis criteria. The two subthreshold diagnostic groups provided strong evidence of difference from the nonhypochondriac controls: comorbidity with psychiatric and medical disorders and healthcare utilization were higher, and quality of life was markedly reduced. The results provide additional support to not only consider "full" DSM-IV hypochondriasis, which is a very rare disorder in the general population, but also to include less restrictive hypochondriac conditions--associated with a clinically relevant degree of psychological and physical impairment--into clinical and scientific considerations.

Analysis of Subthreshold Current Reset Noise in Image Sensors.

PubMed

Teranishi, Nobukazu

2016-05-10

To discuss the reset noise generated by slow subthreshold currents in image sensors, intuitive and simple analytical forms are derived, in spite of the subthreshold current nonlinearity. These solutions characterize the time evolution of the reset noise during the reset operation. With soft reset, the reset noise tends to m k T / 2 C P D when t → ∞ , in full agreement with previously published results. In this equation, C P D is the photodiode (PD) capacitance and m is a constant. The noise has an asymptotic time dependence of t - 1 , even though the asymptotic time dependence of the average (deterministic) PD voltage is as slow as log t . The flush reset method is effective because the hard reset part eliminates image lag, and the soft reset part reduces the noise to soft reset level. The feedback reset with reverse taper control method shows both a fast convergence and a good reset noise reduction. When the feedback amplifier gain, A, is larger, even small value of capacitance, C P , between the input and output of the feedback amplifier will drastically decrease the reset noise. If the feedback is sufficiently fast, the reset noise limit when t → ∞ , becomes m k T ( C P D + C P 1 ) 2 2 q 2 A ( C P D + ( 1 + A ) C P ) in terms of the number of electron in the PD. According to this simple model, if CPD = 10 fF, CP/CPD = 0.01, and A = 2700 are assumed, deep sub-electron rms reset noise is possible.

Fermi LAT Stacking Analysis of Swift Localized GRBs

DOE PAGES

Ackermann, M.; Ajello, M.; Anderson, B.; ...

2016-05-05

In this paper, we perform a comprehensive stacking analysis of data collected by the Fermi Large Area Telescope (LAT) of γ-ray bursts (GRBs) localized by the Swift spacecraft, which were not detected by the LAT but which fell within the instrument's field of view at the time of trigger. We examine a total of 79 GRBs by comparing the observed counts over a range of time intervals to that expected from designated background orbits, as well as by using a joint likelihood technique to model the expected distribution of stacked counts. We find strong evidence for subthreshold emission at MeVmore » to GeV energies using both techniques. This observed excess is detected during intervals that include and exceed the durations typically characterizing the prompt emission observed at keV energies and lasts at least 2700 s after the co-aligned burst trigger. By utilizing a novel cumulative likelihood analysis, we find that although a burst's prompt γ-ray and afterglow X-ray flux both correlate with the strength of the subthreshold emission, the X-ray afterglow flux measured by Swift's X-ray Telescope at 11 hr post trigger correlates far more significantly. Overall, the extended nature of the subthreshold emission and its connection to the burst's afterglow brightness lend further support to the external forward shock origin of the late-time emission detected by the LAT. Finally, these results suggest that the extended high-energy emission observed by the LAT may be a relatively common feature but remains undetected in a majority of bursts owing to instrumental threshold effects.« less

The interplay of seven subthreshold conductances controls the resting membrane potential and the oscillatory behavior of thalamocortical neurons

PubMed Central

Zagha, Edward; Mato, German; Rudy, Bernardo; Nadal, Marcela S.

2014-01-01

The signaling properties of thalamocortical (TC) neurons depend on the diversity of ion conductance mechanisms that underlie their rich membrane behavior at subthreshold potentials. Using patch-clamp recordings of TC neurons in brain slices from mice and a realistic conductance-based computational model, we characterized seven subthreshold ion currents of TC neurons and quantified their individual contributions to the total steady-state conductance at levels below tonic firing threshold. We then used the TC neuron model to show that the resting membrane potential results from the interplay of several inward and outward currents over a background provided by the potassium and sodium leak currents. The steady-state conductances of depolarizing Ih (hyperpolarization-activated cationic current), IT (low-threshold calcium current), and INaP (persistent sodium current) move the membrane potential away from the reversal potential of the leak conductances. This depolarization is counteracted in turn by the hyperpolarizing steady-state current of IA (fast transient A-type potassium current) and IKir (inwardly rectifying potassium current). Using the computational model, we have shown that single parameter variations compatible with physiological or pathological modulation promote burst firing periodicity. The balance between three amplifying variables (activation of IT, activation of INaP, and activation of IKir) and three recovering variables (inactivation of IT, activation of IA, and activation of Ih) determines the propensity, or lack thereof, of repetitive burst firing of TC neurons. We also have determined the specific roles that each of these variables have during the intrinsic oscillation. PMID:24760784

Uncertain behaviours of integrated circuits improve computational performance.

PubMed

Yoshimura, Chihiro; Yamaoka, Masanao; Hayashi, Masato; Okuyama, Takuya; Aoki, Hidetaka; Kawarabayashi, Ken-ichi; Mizuno, Hiroyuki

2015-11-20

Improvements to the performance of conventional computers have mainly been achieved through semiconductor scaling; however, scaling is reaching its limitations. Natural phenomena, such as quantum superposition and stochastic resonance, have been introduced into new computing paradigms to improve performance beyond these limitations. Here, we explain that the uncertain behaviours of devices due to semiconductor scaling can improve the performance of computers. We prototyped an integrated circuit by performing a ground-state search of the Ising model. The bit errors of memory cell devices holding the current state of search occur probabilistically by inserting fluctuations into dynamic device characteristics, which will be actualised in the future to the chip. As a result, we observed more improvements in solution accuracy than that without fluctuations. Although the uncertain behaviours of devices had been intended to be eliminated in conventional devices, we demonstrate that uncertain behaviours has become the key to improving computational performance.

Cognitive Distortions Associated with Imagination of the Thin Ideal: Validation of the Thought-Shape Fusion Body Questionnaire (TSF-B)

PubMed Central

Wyssen, Andrea; Debbeler, Luka J.; Meyer, Andrea H.; Coelho, Jennifer S.; Humbel, Nadine; Schuck, Kathrin; Lennertz, Julia; Messerli-Bürgy, Nadine; Biedert, Esther; Trier, Stephan N.; Isenschmid, Bettina; Milos, Gabriella; Whinyates, Katherina; Schneider, Silvia; Munsch, Simone

2017-01-01

Thought-shape fusion (TSF) describes the experience of body-related cognitive distortions associated with eating disorder (ED) pathology. In the laboratory TSF has been activated by thoughts about fattening/forbidden foods and thin ideals. This study aims at validating a questionnaire to assess the trait susceptibility to TSF (i.e., body-related cognitive distortions) associated with the imagination of thin ideals, and developing an adapted version of the original TSF trait questionnaire, the Thought-Shape Fusion Body Questionnaire (TSF-B). Healthy control women (HC, n = 317) and women diagnosed with subthreshold and clinical EDs (n = 243) completed an online-questionnaire. The factor structure of the TSF-B questionnaire was examined using exploratory (EFA) and subsequent confirmatory factor analysis (CFA). EFA pointed to a two-factor solution, confirmed by CFA. Subscale 1 was named Imagination of thin ideals, containing five items referring to the imagination of female thin ideals. Subscale 2 was named Striving for own thin ideal, with seven items about pursuing/abandoning attempts to reach one’s own thin ideal. The total scale and both subscales showed good convergent validity, excellent reliability, and good ability to discriminate between individuals with subthreshold/clinical EDs and HCs. Results indicate that cognitive distortions are also related to the imagination of thin ideals, and are associated with ED pathology. With two subscales, the TSF-B trait questionnaire appropriately measures this construct. Future studies should clarify whether TSF-B is predictive for the development and course of EDs. Assessing cognitive distortions with the TSF-B questionnaire could improve understanding of EDs and stimulate the development of cognitively oriented interventions. Clinical Trial Registration Number: DRKS-ID: DRKS00005709. PMID:29312059

Remission and recovery associated with lurasidone in the treatment of major depressive disorder with subthreshold hypomanic symptoms (mixed features): post-hoc analysis of a randomized, placebo-controlled study with longer-term extension.

PubMed

Goldberg, Joseph F; Ng-Mak, Daisy; Siu, Cynthia; Chuang, Chien-Chia; Rajagopalan, Krithika; Loebel, Antony

2017-04-01

This post-hoc analysis assessed rates of symptomatic and functional remission, as well as recovery (combination of symptomatic and functional remission), in patients treated with lurasidone for major depressive disorder (MDD) associated with subthreshold hypomanic symptoms (mixed features). Patients with MDD plus two or three manic symptoms (defined as per the DSM-5 mixed-features specifier) were randomly assigned to flexible-dose lurasidone 20-60 mg/day (n=109) or placebo (n=100) for 6 weeks, followed by a 3-month open-label, flexible-dose extension study for U.S. sites only (n=48). Cross-sectional recovery was defined as the presence of both symptomatic remission (Montgomery-Åsberg Depression Rating Scale score ≤ 12) and functional remission (all Sheehan Disability Scale [SDS] domain scores ≤3) at week 6, and at both months 1 and 3 of the extension study ("sustained recovery"). A significantly higher proportion of lurasidone-treated patients (31.3%) achieved recovery (assessed cross-sectionally) compared to placebo (12.2%, p=0.002) at week 6. The number of manic symptoms at baseline moderated the effect size for attaining cross-sectional recovery for lurasidone treatment (vs. placebo) (p=0.028). Sustained recovery rates were higher in patients initially treated with lurasidone (20.8%) versus placebo (12.5%). In this post-hoc analysis of a placebo-controlled study with open-label extension that involved patients with MDD and mixed features, lurasidone was found to significantly improve the rate of recovery at 6 weeks (vs. placebo) that was sustained at month 3 of the extension study. The presence of two (as opposed to three) manic symptoms moderated recovery at the acute study endpoint.

Cognitive flexibility and performance in children and adolescents with threshold and sub-threshold bipolar disorder.

PubMed

Dickstein, Daniel P; Axelson, David; Weissman, Alexandra B; Yen, Shirley; Hunt, Jeffrey I; Goldstein, Benjamin I; Goldstein, Tina R; Liao, Fangzi; Gill, Mary Kay; Hower, Heather; Frazier, Thomas W; Diler, Rasim S; Youngstrom, Eric A; Fristad, Mary A; Arnold, L Eugene; Findling, Robert L; Horwitz, Sarah M; Kowatch, Robert A; Ryan, Neal D; Strober, Michael; Birmaher, Boris; Keller, Martin B

2016-06-01

Greater understanding of cognitive function in children and adolescents with bipolar disorder (BD) is of critical importance to improve our ability to design targeted treatments to help with real-world impairment, including academic performance. We sought to evaluate cognitive performance among children with either BD type I, II, or "not otherwise specified" (NOS) participating in multi-site Course and Outcome of Bipolar Youth study compared to typically developing controls (TDC) without psychopathology. In particular, we sought to test the hypothesis that BD-I and BD-II youths with full threshold episodes of mania or hypomania would have cognitive deficits, including in reversal learning, vs. those BD-NOS participants with sub-threshold episodes and TDCs. N = 175 participants (BD-I = 81, BD-II = 11, BD-NOS = 28, TDC = 55) completed Cambridge Neuropsychological Automated Testing Battery (CANTAB) tasks. A priori analyses of the simple reversal stage of the CANTAB intra-/extra-dimensional shift task showed that aggregated BD-I/II participants required significantly more trials to complete the task than either BD-NOS participants with sub-syndromal manic/hypomanic symptoms or than TDCs. BD participants across sub-types had impairments in sustained attention and information processing for emotionally valenced words. Our results align with prior findings showing that BD-I/II youths with distinct episodes have specific alterations in reversal learning. More broadly, our study suggests that further work is necessary to see the interaction between neurocognitive performance and longitudinal illness course. Additional work is required to identify the neural underpinnings of these differences as targets for potential novel treatments, such as cognitive remediation.

Interaction between harmane, a class of β-carboline alkaloids, and the CA1 serotonergic system in modulation of memory acquisition.

PubMed

Nasehi, Mohammad; Ghadimi, Fatemeh; Khakpai, Fatemeh; Zarrindast, Mohammad-Reza

2017-09-01

This study set to assess the involvement of dorsal hippocampus (CA1) serotonergic system on harmane induced memory acquisition deficit. We used one trial step-down inhibitory avoidancetask to evaluate memory retention and then, open field test to evaluate locomotor activity in adult male NMRI mice. The results showed that pre-training intra-peritoneal (i.p.) administration of harmane (12mg/kg) induced impairment of memory acquisition. Pre-training intra-CA1 administration of 5-HT1B/1D receptor agonist (CP94253; 0.5 and 5ng/mouse) and 5-HT2A/2B/2C receptor agonist (α-methyl 5-HT; 50ng/mouse) impaired memory acquisition. Furthermore, intra-CA1 administration of 5-HT1B/1D receptor antagonist (GR127935; 0.5ng/mouse) and 5-HT2 receptor antagonist (cinancerine; 5ng/mouse) improved memory acquisition. In addition, pre-training intra-CA1 injection of sub-threshold dose of CP94253 (0.05ng/mouse) and α-methyl 5-HT (5ng/mouse) potentiated impairment of memory acquisition induced by harmane (12mg/kg, i.p.). On the other hand, pre-training intra-CA1 infusion of sub-threshold dose of GR127935 (0.05ng/mouse) and cinancerine (0.5ng/mouse) with the administration of harmane (12mg/kg, i.p.) weakened impairment of memory acquisition. Moreover, all above doses of drugs did not change locomotor activity. The present findings suggest that there is an interaction between harmane and the CA1 serotonergic system in modulation of memory acquisition. Copyright © 2017 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

Racial differences in adherence and response to combined treatment for full and subthreshold post-traumatic stress disorder and alcohol use disorders: A secondary analysis.

PubMed

Ruglass, Lesia M; Pedersen, Annelisa; Cheref, Soumia; Hu, Mei-Chen; Hien, Denise A

2016-01-01

We conducted a secondary data analysis to examine whether there were racial differences in adherence and treatment outcomes for participants with co-occurring full and subthreshold post-traumatic stress disorder (PTSD) and alcohol/substance use disorders (A/SUD) who were treated with Seeking Safety (a cognitive-behavioral therapy) and sertraline or Seeking Safety and placebo as part of a clinical trial. Bivarate analyses examined the association between race and adherence, and generalized estimating equations assessed whether race moderated the effect of combination treatment on PTSD and alcohol use outcomes. Except for education, there were no statistically significant racial differences in baseline demographic and psychiatric characteristics. African Americans and Caucasians were equally adherent in number of psychotherapy and medication sessions attended and medication compliance. After controlling for baseline demographics and psychiatric symptoms, however, a race by treatment condition interaction emerged suggesting that African Americans who received the Seeking Safety and sertraline treatment had significantly lower PTSD symptom severity posttreatment and at six months follow-up compared to their counterparts who received Seeking Safety and placebo. No differential effect of treatment condition was found for Caucasians. Moreover, results indicated that a diagnosis of major depressive disorder negatively impacted PTSD symptom recovery for African American participants but not for Caucasians. In conclusion, no differences emerged between African Americans and Caucasians in adherence to combination treatments for PTSD and A/SUD. Findings also suggest assessment and treatment of MDD among African Americans may improve treatment outcomes. More research is needed to determine whether the differential response to Seeking Safety and sertraline among African Americans compared to Caucasians can be replicated.

Clinically Effective Treatment of Fibromyalgia Pain With High-Definition Transcranial Direct Current Stimulation: Phase II Open-Label Dose Optimization.

PubMed

Castillo-Saavedra, Laura; Gebodh, Nigel; Bikson, Marom; Diaz-Cruz, Camilo; Brandao, Rivail; Coutinho, Livia; Truong, Dennis; Datta, Abhishek; Shani-Hershkovich, Revital; Weiss, Michal; Laufer, Ilan; Reches, Amit; Peremen, Ziv; Geva, Amir; Parra, Lucas C; Fregni, Felipe

2016-01-01

Despite promising preliminary results in treating fibromyalgia (FM) pain, no neuromodulation technique has been adopted in clinical practice because of limited efficacy, low response rate, or poor tolerability. This phase II open-label trial aims to define a methodology for a clinically effective treatment of pain in FM by establishing treatment protocols and screening procedures to maximize efficacy and response rate. High-definition transcranial direct current stimulation (HD-tDCS) provides targeted subthreshold brain stimulation, combining tolerability with specificity. We aimed to establish the number of HD-tDCS sessions required to achieve a 50% FM pain reduction, and to characterize the biometrics of the response, including brain network activation pain scores of contact heat-evoked potentials. We report a clinically significant benefit of a 50% pain reduction in half (n = 7) of the patients (N = 14), with responders and nonresponders alike benefiting from a cumulative effect of treatment, reflected in significant pain reduction (P = .035) as well as improved quality of life (P = .001) over time. We also report an aggregate 6-week response rate of 50% of patients and estimate 15 as the median number of HD-tDCS sessions to reach clinically meaningful outcomes. The methodology for a pivotal FM neuromodulation clinical trial with individualized treatment is thus supported. Registered in Clinicaltrials.gov under registry number NCT01842009. In this article, an optimized protocol for the treatment of fibromyalgia pain with targeted subthreshold brain stimulation using high-definition transcranial direct current stimulation is outlined. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

Escalation to Major Depressive Disorder among adolescents with subthreshold depressive symptoms: evidence of distinct subgroups at risk.

PubMed

Hill, Ryan M; Pettit, Jeremy W; Lewinsohn, Peter M; Seeley, John R; Klein, Daniel N

2014-04-01

The presence of subthreshold depressive symptoms (SubD) in adolescence is associated with high prospective risk of developing Major Depressive Disorder (MDD). Little is known about variables that predict escalation from SubD to MDD. This study used a longitudinal prospective design in a community sample of adolescents to identify combinations of risk factors that predicted escalation from SubD to MDD. Classification tree analysis was used to identify combinations of risk factors that improved the sensitivity and specificity of prediction of MDD onset among 424 adolescents with a lifetime history of SubD. Of the 424, 144 developed MDD during the follow-up period. Evidence for multiple subgroups was found: among adolescents with poor friend support, the highest risk of escalation was among participants with lifetime histories of an anxiety or substance use disorder. Among adolescents with high friend support, those reporting multiple major life events in the past year or with a history of an anxiety disorder were at highest risk of escalation. Study findings may not inform prevention efforts for individuals who first develop SubD during adulthood. This study did not examine the temporal ordering of predictors involved in escalation from SubD to MDD. Adolescents with a history of SubD were at highest risk of escalation to MDD in the presence of poor friend support and an anxiety or substance use disorder, or in the presence of better friend support, multiple major life events, and an anxiety disorder. Findings may inform case identification approaches for adolescent depression prevention programs. Copyright © 2014 Elsevier B.V. All rights reserved.

Analytical modeling of trilayer graphene nanoribbon Schottky-barrier FET for high-speed switching applications.

PubMed

Rahmani, Meisam; Ahmadi, Mohammad Taghi; Abadi, Hediyeh Karimi Feiz; Saeidmanesh, Mehdi; Akbari, Elnaz; Ismail, Razali

2013-01-30

Recent development of trilayer graphene nanoribbon Schottky-barrier field-effect transistors (FETs) will be governed by transistor electrostatics and quantum effects that impose scaling limits like those of Si metal-oxide-semiconductor field-effect transistors. The current-voltage characteristic of a Schottky-barrier FET has been studied as a function of physical parameters such as effective mass, graphene nanoribbon length, gate insulator thickness, and electrical parameters such as Schottky barrier height and applied bias voltage. In this paper, the scaling behaviors of a Schottky-barrier FET using trilayer graphene nanoribbon are studied and analytically modeled. A novel analytical method is also presented for describing a switch in a Schottky-contact double-gate trilayer graphene nanoribbon FET. In the proposed model, different stacking arrangements of trilayer graphene nanoribbon are assumed as metal and semiconductor contacts to form a Schottky transistor. Based on this assumption, an analytical model and numerical solution of the junction current-voltage are presented in which the applied bias voltage and channel length dependence characteristics are highlighted. The model is then compared with other types of transistors. The developed model can assist in comprehending experiments involving graphene nanoribbon Schottky-barrier FETs. It is demonstrated that the proposed structure exhibits negligible short-channel effects, an improved on-current, realistic threshold voltage, and opposite subthreshold slope and meets the International Technology Roadmap for Semiconductors near-term guidelines. Finally, the results showed that there is a fast transient between on-off states. In other words, the suggested model can be used as a high-speed switch where the value of subthreshold slope is small and thus leads to less power consumption.

Vibration-enhanced posture stabilization achieved by tactile supplementation: may blind individuals get extra benefits?

PubMed

Magalhães, Fernando Henrique; Kohn, André Fabio

2011-08-01

Diminished balance ability poses a serious health risk due to the increased likelihood of falling, and impaired postural stability is significantly associated with blindness and poor vision. Noise stimulation (by improving the detection of sub-threshold somatosensory information) and tactile supplementation (i.e., additional haptic information provided by an external contact surface) have been shown to improve the performance of the postural control system. Moreover, vibratory noise added to the source of tactile supplementation (e.g., applied to a surface that the fingertip touches) has been shown to enhance balance stability more effectively than tactile supplementation alone. In view of the above findings, in addition to the well established consensus that blind subjects show superior abilities in the use of tactile information, we hypothesized that blind subjects may take extra benefits from the vibratory noise added to the tactile supplementation and hence show greater improvements in postural stability than those observed for sighted subjects. If confirmed, this hypothesis may lay the foundation for the development of noise-based assistive devices (e.g., canes, walking sticks) for improving somatosensation and hence prevent falls in blind individuals. Copyright © 2011 Elsevier Ltd. All rights reserved.

Investigation of dielectric pocket induced variations in tunnel field effect transistor

NASA Astrophysics Data System (ADS)

Upasana; Narang, Rakhi; Saxena, Manoj; Gupta, Mridula

2016-04-01

The performance of conventional Tunnel FETs struggling from ambipolar issues, insufficient on-current, lower transconductance value, higher delay and lower cut off frequency has been improved by introducing several material and device engineering concepts in past few years. Keeping this in view, another interesting and reliable option i.e. Dielectric Pocket TFET (featuring a dielectric pocket placement near tunneling junction) has been comprehensively and qualitatively demonstrated using ATLAS device simulator. The architecture has been explored in terms of various device electrostatic parameters such as potential, energy band profile, electron and hole concentration, electric field variation and band to band generation rate (GBTB) near the tunneling junction where the Dielectric Pocket (DP) has been introduced. Subsequently, a detailed investigation by changing the position and dielectric constant of pocket at respective junctions has been made where DP induced variations in drain current, transconductance and parasitic capacitance have been examined. The work highlights major improvements over conventional TFET in terms of lower subthreshold swing and threshold voltage, higher drain current and transconductance, improved on-to-off current ratio, suppressed ambipolar conduction and improved dynamic power dissipation issues for low voltage analog and digital applications.

Gate engineered heterostructure junctionless TFET with Gaussian doping profile for ambipolar suppression and electrical performance improvement

NASA Astrophysics Data System (ADS)

Aghandeh, Hadi; Sedigh Ziabari, Seyed Ali

2017-11-01

This study investigates a junctionless tunnel field-effect transistor with a dual material gate and a heterostructure channel/source interface (DMG-H-JLTFET). We find that using the heterostructure interface improves device behavior by reducing the tunneling barrier width at the channel/source interface. Simultaneously, the dual material gate structure decreases ambipolar current by increasing the tunneling barrier width at the drain/channel interface. The performance of the device is analyzed based on the energy band diagram at on, off, and ambipolar states. Numerical simulations demonstrate improvements in ION, IOFF, ION/IOFF, subthreshold slope (SS), transconductance and cut-off frequency and suppressed ambipolar behavior. Next, the workfunction optimization of dual material gate is studied. It is found that if appropriate workfunctions are selected for tunnel and auxiliary gates, the JLTFET exhibits considerably improved performance. We then study the influence of Gaussian doping distribution at the drain and the channel on the ambipolar performance of the device and find that a Gaussian doping profile and a dual material gate structure remarkably reduce ambipolar current. Gaussian doped DMG-H-JLTFET, also exhibits enhanced IOFF, ION/IOFF, SS and a low threshold voltage without degrading IOFF.

High work function materials for source/drain contacts in printed polymer thin film transistors

NASA Astrophysics Data System (ADS)

Sholin, V.; Carter, S. A.; Street, R. A.; Arias, A. C.

2008-02-01

Studies of materials for source-drain electrodes in ink-jet printed polymer-based thin film transistors (TFTs) are reported. Two systems are studied: a blend of Ag nanoparticles with poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) and an ethylene glycol-doped PEDOT:PSS solution (modified-PEDOT). The semiconductor used is the polythiophene derivative poly [5,5'-bis(3-dodecyl-2-thienyl)-2,2,2'-bithiophene]. PEDOT:Ag blends and modified-PEDOT yield TFTs with mobilities around 10-2 and 10-3cm2/Vs, respectively, subthreshold slopes around 1.6V/decade and on-to-off current ratios of 106-107. Both systems show considerable improvement over printed TFTs with Ag nanoparticle source-drain electrodes. Results on film resistivity and morphology are discussed along with device characteristic analysis.

A computational study of a novel graphene nanoribbon field effect transistor

NASA Astrophysics Data System (ADS)

Ghoreishi, Seyed Saleh; Yousefi, Reza

2017-04-01

In this paper, using gate structure engineering and modification of channel dopant profile, we propose a new double gate graphene nanoribbon field effect transistor (DG-GNRFET) mainly to suppress the band-to-band tunneling (BTBT) of carriers. In the new device, the intrinsic part of the channel is replaced by an intrinsic-lightly doped-intrinsic (I -N--I) configuration in a way that only the intrinsic parts are covered by the gate contact. Transport characteristics of the device are investigated theoretically using the nonequilibrium Green’s function (NEGF) formalism. Numerical simulations show that off-current, ambipolar behavior, on/off-current ratio and the switching characteristics such as intrinsic delay and power-delay product are improved. In addition, the new device demonstrates better sub-threshold swing and less drain-induced barrier lowering (DIBL).

All-optical electrophysiology in mammalian neurons using engineered microbial rhodopsins

PubMed Central

Hochbaum, Daniel R.; Zhao, Yongxin; Farhi, Samouil L.; Klapoetke, Nathan; Werley, Christopher A.; Kapoor, Vikrant; Zou, Peng; Kralj, Joel M.; Maclaurin, Dougal; Smedemark-Margulies, Niklas; Saulnier, Jessica L.; Boulting, Gabriella L.; Straub, Christoph; Cho, Yong Ku; Melkonian, Michael; Wong, Gane Ka-Shu; Harrison, D. Jed; Murthy, Venkatesh N.; Sabatini, Bernardo; Boyden, Edward S.; Campbell, Robert E.; Cohen, Adam E.

2014-01-01

All-optical electrophysiology—spatially resolved simultaneous optical perturbation and measurement of membrane voltage—would open new vistas in neuroscience research. We evolved two archaerhodopsin-based voltage indicators, QuasAr1 and 2, which show improved brightness and voltage sensitivity, microsecond response times, and produce no photocurrent. We engineered a novel channelrhodopsin actuator, CheRiff, which shows improved light sensitivity and kinetics, and spectral orthogonality to the QuasArs. A co-expression vector, Optopatch, enabled crosstalk-free genetically targeted all-optical electrophysiology. In cultured neurons, we combined Optopatch with patterned optical excitation to probe back-propagating action potentials in dendritic spines, synaptic transmission, sub-cellular microsecond-timescale details of action potential propagation, and simultaneous firing of many neurons in a network. Optopatch measurements revealed homeostatic tuning of intrinsic excitability in human stem cell-derived neurons. In brain slice, Optopatch induced and reported action potentials and subthreshold events, with high signal-to-noise ratios. The Optopatch platform enables high-throughput, spatially resolved electrophysiology without use of conventional electrodes. PMID:24952910

Effects of annealing gas and drain doping concentration on electrical properties of Ge-source/Si-channel heterojunction tunneling FETs

NASA Astrophysics Data System (ADS)

Bae, Tae-Eon; Wakabayashi, Yuki; Nakane, Ryosho; Takenaka, Mitsuru; Takagi, Shinichi

2018-04-01

Improvement in the performance of Ge-source/Si-channel heterojunction tunneling FETs (TFETs) with high on-current/off-current (I on/I off) ratio and steep subthreshold swing (SS) is demonstrated. In this paper, we experimentally examine the effects of gas ambient [N2 and forming gas (4% H2/N2)] and a doping concentration in the drain regions on the electrical characteristics of Ge/Si heterojunction TFETs. The minimum SS (SSmin) of 70.9 mV/dec and the large I on/I off ratio of 1.4 × 107 are realized by postmetallization annealing in forming gas. Also, the steep SSmin and averaged SS (SSavr) values of 64.2 and 78.4 mV/dec, respectively, are obtained in low drain doping concentration. This improvement is attributable to the reduction in interface state density (D it) in the channel region and to the low leakage current in the drain region.

Solution-processable alumina: PVP nanocomposite dielectric layer for high-performance organic thin-film transistors

NASA Astrophysics Data System (ADS)

Lin, Hui; Kong, Xiao; Li, Yiran; Kuang, Peng; Tao, Silu

2018-03-01

In this article, we have investigated the effect of nanocomposite gate dielectric layer built by alumina (Al2O3) and poly(4-vinyphenol) (PVP) with solution method which could enhance the dielectric capability and decrease the surface polarity. Then, we used modify layer to optimize the surface morphology of dielectric layer to further improve the insulation capability, and finally we fabricated the high-performance and low-voltage organic thin-film transistors by using this nanocomposite dielectric layer. The result shows that the devices with Al2O3:10%PVP dielectric layer with a modified layer exhibited a mobility of 0.49 cm2/Vs, I on/Ioff ratio of 7.8 × 104, threshold voltage of - 1.2 V, sub-threshold swing of 0.3 V/dec, and operating voltage as low as - 4 V. The improvement of devices performance was owing to the good insulation capability, appropriate capacitance of dielectric layer, and preferable interface contact, smaller crystalline size of active layer.

Improved performance of graphene transistors by strain engineering.

PubMed

Nguyen, V Hung; Nguyen, Huy-Viet; Dollfus, P

2014-04-25

By means of numerical simulation, in this work we study the effects of uniaxial strain on the transport properties of strained graphene heterojunctions and explore the possibility of achieving good performance of graphene transistors using these hetero-channels. It is shown that a finite conduction gap can open in the strain junctions due to strain-induced deformation of the graphene bandstructure. These hetero-channels are then demonstrated to significantly improve the operation of graphene field-effect transistors (FETs). In particular, the ON/OFF current ratio can reach a value of over 10(5). In graphene normal FETs, the transconductance, although reduced compared to the case of unstrained devices, is still high, while good saturation of current can be obtained. This results in a high voltage gain and a high transition frequency of a few hundreds of GHz for a gate length of 80 nm. In graphene tunneling FETs, subthreshold swings lower than 30 mV /dec, strong nonlinear effects such as gate-controllable negative differential conductance, and current rectification are observed.

A Subthreshold Digital Library Using a Dynamic-Threshold Metal-Oxide Semiconductor (DTMOS) and Transmission Gate Logic

DTIC Science & Technology

2014-09-01

electrocardiography (ECG), electromyography (EMG), and electroencephalography (EEG) applications that operate using thermoelectrically generated energy...semiconductor ECG electrocardiography EEG electroencephalography EMG electromyography FY15 fiscal year 2015 IC integrated circuit MOSFETs

Evidence for Long-Timescale Patterns of Synaptic Inputs in CA1 of Awake Behaving Mice.

PubMed

Kolb, Ilya; Talei Franzesi, Giovanni; Wang, Michael; Kodandaramaiah, Suhasa B; Forest, Craig R; Boyden, Edward S; Singer, Annabelle C

2018-02-14

Repeated sequences of neural activity are a pervasive feature of neural networks in vivo and in vitro In the hippocampus, sequential firing of many neurons over periods of 100-300 ms reoccurs during behavior and during periods of quiescence. However, it is not known whether the hippocampus produces longer sequences of activity or whether such sequences are restricted to specific network states. Furthermore, whether long repeated patterns of activity are transmitted to single cells downstream is unclear. To answer these questions, we recorded intracellularly from hippocampal CA1 of awake, behaving male mice to examine both subthreshold activity and spiking output in single neurons. In eight of nine recordings, we discovered long (900 ms) reoccurring subthreshold fluctuations or "repeats." Repeats generally were high-amplitude, nonoscillatory events reoccurring with 10 ms precision. Using statistical controls, we determined that repeats occurred more often than would be expected from unstructured network activity (e.g., by chance). Most spikes occurred during a repeat, and when a repeat contained a spike, the spike reoccurred with precision on the order of ≤20 ms, showing that long repeated patterns of subthreshold activity are strongly connected to spike output. Unexpectedly, we found that repeats occurred independently of classic hippocampal network states like theta oscillations or sharp-wave ripples. Together, these results reveal surprisingly long patterns of repeated activity in the hippocampal network that occur nonstochastically, are transmitted to single downstream neurons, and strongly shape their output. This suggests that the timescale of information transmission in the hippocampal network is much longer than previously thought. SIGNIFICANCE STATEMENT We found long (≥900 ms), repeated, subthreshold patterns of activity in CA1 of awake, behaving mice. These repeated patterns ("repeats") occurred more often than expected by chance and with 10 ms precision. Most spikes occurred within repeats and reoccurred with a precision on the order of 20 ms. Surprisingly, there was no correlation between repeat occurrence and classical network states such as theta oscillations and sharp-wave ripples. These results provide strong evidence that long patterns of activity are repeated and transmitted to downstream neurons, suggesting that the hippocampus can generate longer sequences of repeated activity than previously thought. Copyright © 2018 the authors 0270-6474/18/381822-14$15.00/0.

Self-help interventions for depressive disorders and depressive symptoms: a systematic review.

PubMed

Morgan, Amy J; Jorm, Anthony F

2008-08-19

Research suggests that depressive disorders exist on a continuum, with subthreshold symptoms causing considerable population burden and increasing individual risk of developing major depressive disorder. An alternative strategy to professional treatment of subthreshold depression is population promotion of effective self-help interventions that can be easily applied by an individual without professional guidance. The evidence for self-help interventions for depressive symptoms is reviewed in the present work, with the aim of identifying promising interventions that could inform future health promotion campaigns or stimulate further research. A literature search for randomised controlled trials investigating self-help interventions for depressive disorders or depressive symptoms was performed using PubMed, PsycINFO and the Cochrane Database of Systematic Reviews. Reference lists and citations of included studies were also checked. Studies were grouped into those involving participants with depressive disorders or a high level of depressive symptoms, or non-clinically depressed participants not selected for depression. A number of exclusion criteria were applied, including trials with small sample sizes and where the intervention was adjunctive to antidepressants or psychotherapy. The majority of interventions searched had no relevant evidence to review. Of the 38 interventions reviewed, the ones with the best evidence of efficacy in depressive disorders were S-adenosylmethionine, St John's wort, bibliotherapy, computerised interventions, distraction, relaxation training, exercise, pleasant activities, sleep deprivation, and light therapy. A number of other interventions showed promise but had received less research attention. Research in non-clinical samples indicated immediate beneficial effects on depressed mood for distraction, exercise, humour, music, negative air ionisation, and singing; while potential for helpful longer-term effects was found for autogenic training, light therapy, omega 3 fatty acids, pets, and prayer. Many of the trials were poor quality and may not generalize to self-help without professional guidance. A number of self-help interventions have promising evidence for reducing subthreshold depressive symptoms. Other forms of evidence such as expert consensus may be more appropriate for interventions that are not feasible to evaluate in randomised controlled trials. There needs to be evaluation of whether promotion to the public of effective self-help strategies for subthreshold depressive symptoms could delay or prevent onset of depressive illness, reduce functional impairment, and prevent progression to other undesirable outcomes such as harmful use of substances.

Histotripsy Lesion Formation Using an Ultrasound Imaging Probe Enabled by a Low-Frequency Pump Transducer.

PubMed

Lin, Kuang-Wei; Hall, Timothy L; Xu, Zhen; Cain, Charles A

2015-08-01

When histotripsy pulses shorter than 2 cycles are applied, the formation of a dense bubble cloud relies only on the applied peak negative pressure (p-) exceeding the "intrinsic threshold" of the medium (absolute value of 26-30 MPa in most soft tissues). It has been found that a sub-threshold high-frequency probe pulse (3 MHz) can be enabled by a sub-threshold low-frequency pump pulse (500 kHz) where the sum exceeds the intrinsic threshold, thus generating lesion-producing dense bubble clouds ("dual-beam histotripsy"). Here, the feasibility of using an imaging transducer to provide the high-frequency probe pulse in the dual-beam histotripsy approach is investigated. More specifically, an ATL L7-4 imaging transducer (Philips Healthcare, Andover, MA, USA), pulsed by a V-1 Data Acquisition System (Verasonics, Redmond, WA, USA), was used to generate the high-frequency probe pulses. The low-frequency pump pulses were generated by a 20-element 345-kHz array transducer, driven by a custom high-voltage pulser. These dual-beam histotripsy pulses were applied to red blood cell tissue-mimicking phantoms at a pulse repetition frequency of 1 Hz, and optical imaging was used to visualize bubble clouds and lesions generated in the red blood cell phantoms. The results indicated that dense bubble clouds (and resulting lesions) were generated when the p- of the sub-threshold pump and probe pulses combined constructively to exceed the intrinsic threshold. The average size of the smallest reproducible lesions using the imaging probe pulse enabled by the sub-threshold pump pulse was 0.7 × 1.7 mm, whereas that using the supra-threshold pump pulse alone was 1.4 × 3.7 mm. When the imaging transducer was steered laterally, bubble clouds and lesions were steered correspondingly until the combined p- no longer exceeded the intrinsic threshold. These results were also validated with ex vivo porcine liver experiments. Using an imaging transducer for dual-beam histotripsy can have two advantages: (i) lesion steering can be achieved using the steering of the imaging transducer (implemented with the beamformer of the accompanying programmable ultrasound system), and (ii) treatment can be simultaneously monitored when the imaging transducer is used in conjunction with an ultrasound imaging system. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Histotripsy Lesion Formation using an Ultrasound Imaging Probe Enabled by a Low-Frequency Pump Transducer

PubMed Central

Lin, Kuang-Wei; Hall, Timothy L.; Xu, Zhen; Cain, Charles A.

2015-01-01

When applying histotripsy pulses shorter than 2 cycles, the formation of a dense bubble cloud only relies on the applied peak negative pressure (p-) exceeding the “intrinsic threshold” of the medium (absolute value of 26 – 30 MPa in most soft tissue). A previous study conducted by our research group showed that a sub-threshold high-frequency probe pulse (3 MHz) can be enabled by a sub-threshold low-frequency pump pulse (500 kHz) where the sum exceeds the intrinsic threshold, thus generating lesion-producing dense bubble clouds (“dual-beam histotripsy”). This paper investigates the feasibility of using an imaging transducer to provide the high-frequency probe pulse in the dual-beam histotripsy approach. More specifically, an ATL L7–4 imaging transducer, pulsed by a Verasonics V-1 Data Acquisition System, was used to generate the high-frequency probe pulses. The low-frequency pump pulses were generated by a 20-element 345 kHz array transducer, driven by a custom high voltage pulser. These dual-beam histotripsy pulses were applied to red-blood-cell (RBC) tissue-mimicking phantoms at a pulse repetition frequency of 1 Hz, and optical imaging was used to visualize bubble clouds and lesions generated in the RBC phantoms. The results showed that dense bubble clouds (and resulting lesions) were generated when the p- of the sub-threshold pump and probe pulses combined constructively to exceed the intrinsic threshold. The average size of the smallest reproducible lesions using the imaging probe pulse enabled by the sub-threshold pump pulse was 0.7 × 1.7 mm while that using the supra-threshold pump pulse alone was 1.4 × 3.7 mm. When the imaging transducer was steered laterally, bubble clouds and lesions were steered correspondingly until the combined p- no longer exceeded the intrinsic threshold. These results were also validated with ex vivo porcine liver experiments. Using an imaging transducer for dual-beam histotripsy can have two advantages, 1) lesion steering can be achieved using the steering of the imaging transducer (implemented with the beamformer of the accompanying programmable ultrasound system) and 2) treatment can be simultaneously monitored when the imaging transducer is used in conjunction with an ultrasound imaging system. PMID:25929995

Self-help interventions for depressive disorders and depressive symptoms: a systematic review

PubMed Central

Morgan, Amy J; Jorm, Anthony F

2008-01-01

Background Research suggests that depressive disorders exist on a continuum, with subthreshold symptoms causing considerable population burden and increasing individual risk of developing major depressive disorder. An alternative strategy to professional treatment of subthreshold depression is population promotion of effective self-help interventions that can be easily applied by an individual without professional guidance. The evidence for self-help interventions for depressive symptoms is reviewed in the present work, with the aim of identifying promising interventions that could inform future health promotion campaigns or stimulate further research. Methods A literature search for randomised controlled trials investigating self-help interventions for depressive disorders or depressive symptoms was performed using PubMed, PsycINFO and the Cochrane Database of Systematic Reviews. Reference lists and citations of included studies were also checked. Studies were grouped into those involving participants with depressive disorders or a high level of depressive symptoms, or non-clinically depressed participants not selected for depression. A number of exclusion criteria were applied, including trials with small sample sizes and where the intervention was adjunctive to antidepressants or psychotherapy. Results The majority of interventions searched had no relevant evidence to review. Of the 38 interventions reviewed, the ones with the best evidence of efficacy in depressive disorders were S-adenosylmethionine, St John's wort, bibliotherapy, computerised interventions, distraction, relaxation training, exercise, pleasant activities, sleep deprivation, and light therapy. A number of other interventions showed promise but had received less research attention. Research in non-clinical samples indicated immediate beneficial effects on depressed mood for distraction, exercise, humour, music, negative air ionisation, and singing; while potential for helpful longer-term effects was found for autogenic training, light therapy, omega 3 fatty acids, pets, and prayer. Many of the trials were poor quality and may not generalise to self-help without professional guidance. Conclusion A number of self-help interventions have promising evidence for reducing subthreshold depressive symptoms. Other forms of evidence such as expert consensus may be more appropriate for interventions that are not feasible to evaluate in randomised controlled trials. There needs to be evaluation of whether promotion to the public of effective self-help strategies for subthreshold depressive symptoms could delay or prevent onset of depressive illness, reduce functional impairment, and prevent progression to other undesirable outcomes such as harmful use of substances. PMID:18710579

Do Generalist Parenting Programmes Improve Children's Behaviour and Attendance at School? The Parents' Perspective

ERIC Educational Resources Information Center

Rogers, Lynne; Hallam, Susan; Shaw, Jacquelene

2008-01-01

Previous research has demonstrated that parenting programmes can be an effective intervention in changing behaviour and parent-child interactions. However, less attention has been given to the impact of these programmes in relation to improving attendance and behaviour at school. Lynne Rogers, lecturer in teacher education specialising in the…

Twins with Autism: Utilising Video Feedback to Improve Job-Related Behaviours

ERIC Educational Resources Information Center

Mackey, Megan; Nelson, Gretchen

2015-01-01

Employment for individuals with autism spectrum disorders (ASD) is a significant factor in assuring quality of life in adulthood. The research reported in this article examines the effectiveness of video feedback (VFB) in improving the job-related behaviours of twin adolescents with ASD and learning disabilities. The targeted behaviours included…

Can a Brief Educational Intervention Improve Parents' Knowledge of Healthy Children's Sleep? A Pilot-Test

ERIC Educational Resources Information Center

Jones, Caroline H. D.; Owens, Judith A.; Pham, Brian

2013-01-01

Objective: Insufficient and poor quality sleep is prevalent in children, and is a significant public health concern due to the negative consequences for health. Certain sleep-related behaviours are associated with improved sleep, and sleep behaviours are amenable to efforts targeted towards behaviour change. Parental educational interventions have…

Silymarin improves the behavioural, biochemical and histoarchitecture alterations in focal ischemic rats: a comparative evaluation with piracetam and protocatachuic acid.

PubMed

Muley, Milind M; Thakare, Vishnu N; Patil, Rajesh R; Kshirsagar, Ajay D; Naik, Suresh R

2012-08-01

Comparative neuroprotective potential of silymarin, piracetam and protocatechuic acid ethyl ester (PCA) was evaluated in focal ischemic rats. Various pharmacological, biochemical (lipid peroxidation, reduced glutathione, catalase, nitrite content, brain water content) and behavioural (memory impairment, motor control, neurological score) including infarct size and histopathological alterations were evaluated. Silymarin (200mg/kg) and PCA treatment significantly improved behavioural, biochemical and histopathological changes, and reduced water content and infarct size. However, piracetam only improved behavioural and histopathological changes, reduced water content and infarct size. The findings indicate that silymarin exhibits neuroprotective activity better than PCA and piracetam in focal ischemia/reperfusion reflected by its better restoration of behavioural and antioxidant profile. Copyright © 2012 Elsevier Inc. All rights reserved.

NEUROPSYCHOLOGICAL REMEDIATION OF HYPERACTIVE CHILDREN

PubMed Central

Agarwal, Neena; Rao, Shobini L.

1997-01-01

Hyperkinesis is associated with deficits of attention (poor allocation of attention resources, susceptibility to interference and perseveration); vigilance and perceptual sensitivity. Three boys aged 7-8 years with simple hyperkinesis were given cognitive tasks to improve the above functions in daily one hour sessions for a month. The children improved significantly in the above functions and behaviour. Three other children aged 5-8 years with simple hyperkinesis who were on medication improved only slightly in their behaviour during this period. Behavioural intervention and parental counselling were additional inputs to the children in both groups. Neuropsychological remediation combined with parental counselling and behavioural intervention shows promise in treating hyperactive children. PMID:21584098

Applying psychological frameworks of behaviour change to improve healthcare worker hand hygiene: a systematic review.

PubMed

Srigley, J A; Corace, K; Hargadon, D P; Yu, D; MacDonald, T; Fabrigar, L; Garber, G

2015-11-01

Despite the importance of hand hygiene in preventing transmission of healthcare-associated infections, compliance rates are suboptimal. Hand hygiene is a complex behaviour and psychological frameworks are promising tools to influence healthcare worker (HCW) behaviour. (i) To review the effectiveness of interventions based on psychological theories of behaviour change to improve HCW hand hygiene compliance; (ii) to determine which frameworks have been used to predict HCW hand hygiene compliance. Multiple databases and reference lists of included studies were searched for studies that applied psychological theories to improve and/or predict HCW hand hygiene. All steps in selection, data extraction, and quality assessment were performed independently by two reviewers. The search yielded 918 citations; seven met eligibility criteria. Four studies evaluated hand hygiene interventions based on psychological frameworks. Interventions were informed by goal setting, control theory, operant learning, positive reinforcement, change theory, the theory of planned behaviour, and the transtheoretical model. Three predictive studies employed the theory of planned behaviour, the transtheoretical model, and the theoretical domains framework. Interventions to improve hand hygiene adherence demonstrated efficacy but studies were at moderate to high risk of bias. For many studies, it was unclear how theories of behaviour change were used to inform the interventions. Predictive studies had mixed results. Behaviour change theory is a promising tool for improving hand hygiene; however, these theories have not been extensively examined. Our review reveals a significant gap in the literature and indicates possible avenues for novel research. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Reducing Disruptive Behaviours and Improving Classroom Behavioural Climate with Class-Wide Positive Behaviour Support in Middle Schools

ERIC Educational Resources Information Center

Närhi, Vesa; Kiiski, Tiina; Savolainen, Hannu

2017-01-01

Disruptive behaviour in classrooms is a significant challenge for learning in schools and a risk factor for students' academic achievement and a significant source of teachers' work-related stress. Earlier research shows that clear behavioural expectations, monitoring students' adherence to them and behaviour-specific praise are effective…

Predictors of changes in child behaviour following parent management training: Child, context, and therapy factors.

PubMed

Hagen, Kristine Amlund; Ogden, Terje

2017-04-01

This non-randomised study examined a set of predictive factors of changes in child behaviour following parent management training (PMTO). Families of 331 Norwegian girls (26%) and boys with clinic-level conduct problems participated. The children ranged in age from 3 to 12 years (M age = 8.69). Retention rate was 72.2% at post-assessment. Child-, parent- and therapy-level variables were entered as predictors of multi-informant reported change in externalising behaviour and social skills. Behavioural improvements following PMTO amounted to 1 standard deviation on parent rated and ½ standard deviation on teacher rated externalising behaviour, while social skills improvements were more modest. Results suggested that children with higher symptom scores and lower social skills score at pre-treatment were more likely to show improvements in these areas. According to both parent- and teacher-ratings, girls tended to show greater improvements in externalising behaviour and social skills following treatment and, according to parents, ADHD symptomology appeared to inhibit improvements in social skills. Finally, observed increases in parental skill encouragement, therapists' satisfaction with treatment and the number of hours spent in therapy by children were also positive and significant predictors of child outcomes. © 2016 International Union of Psychological Science.

Effectiveness of cognitive behavioural therapy in a community-based pulmonary rehabilitation programme: A controlled clinical trial.

PubMed

Luk, Edwin K; Gorelik, Alexandra; Irving, Louis; Khan, Fary

2017-03-06

To investigate whether the use of cognitive behavioural therapy in pulmonary rehabilitation addresses the depression and anxiety burden and thereby improves rehabilitation outcomes. Prospective controlled clinical trial. A total of 70 patients with chronic obstructive pulmonary disease who were referred to a community centre for pulmonary rehabilitation. Patients were allocated to either the control group, consisting of pulmonary rehabilitation alone, or to the treatment group, receiving pulmonary rehabilitation and an additional 6 sessions of group-based cognitive behavioural therapy. Assessments consisting of questionnaires and walk tests were conducted pre- and post-pulmonary rehabilitation. A total of 28 patients were enrolled. The cognitive behavioural therapy group had significant improvements in exercise capacity following pulmonary rehabilitation (mean change 32.9 m, p = 0.043), which was maintained at 3 months post-pulmonary rehabilitation (mean change 23.4 m, p = 0.045). Patients in the cognitive behavioural therapy group showed significant short-term improvements in fatigue, stress and depression (mean change 2.4, p = 0.016, 3.9, p = 0.024 and 4.3, p = 0.047, respectively) and a 3-month post-pulmonary rehabilitation improvement in anxiety score (mean change 3.1, p = 0.01). No significant changes were seen in the control group. The addition of cognitive behavioural therapy improved patients' physical, psychological and quality of life results. Cognitive behavioural therapy should be considered for inclusion in a pulmonary rehabilitation programme to enhance outcomes.

Increasing the Teacher Rate of Behaviour Specific Praise and its Effect on a Child with Aggressive Behaviour Problems

ERIC Educational Resources Information Center

Moffat, Thecla Kudakwashe

2011-01-01

A single subject design was used to investigate the effectiveness of an increase in teacher behaviour-specific praise statements to address anti-social behaviours demonstrated by a student who displays aggressive behaviours. Researchers agree that praise is effective in improving problem behaviours. They also agree that training teachers to use…

Mentalization-based treatment in groups for adolescents with borderline personality disorder (BPD) or subthreshold BPD versus treatment as usual (M-GAB): study protocol for a randomized controlled trial.

PubMed

Beck, Emma; Bo, Sune; Gondan, Matthias; Poulsen, Stig; Pedersen, Liselotte; Pedersen, Jesper; Simonsen, Erik

2016-07-12

Evidence-based outpatient psychotherapeutic programs are first-line treatment of borderline personality disorder (BPD). Early and effective treatment of BPD is crucial to the prevention of its individual, psychosocial, and economic consequences. However, in spite of recent advantages in diagnosing adolescent BPD, there is a lack of cost-effective evidence-based treatment programs for adolescents. Mentalization-based treatment is an evidence-based program for BPD, originally developed for adults. We will investigate whether a specifically designed mentalization-based treatment in groups is an efficacious treatment for adolescents with BPD or subthreshold BPD compared to treatment as usual. The trial is a four-center, two-armed, parallel-group, assessor-blinded randomized clinical superiority trial. One hundred twelve patients aged 14 to 17 referred to Child and Adolescent Psychiatric Clinics in Region Zealand are randomized to 1 year of either mentalization-based treatment in groups or treatment as usual. Patients will be included if they meet at least four DSM-5 criteria for BPD. The primary outcome is self-reported borderline features at discharge. Secondary outcomes will include self-harm, depression, BPD criteria, externalizing and internalizing symptoms, and social functioning, together with parental reports on borderline features, externalizing and internalizing symptoms. Measures of attachment and mentalization will be included as mediational variables. Follow-up assessment will take place at 3 and 12 months after end of treatment. This is the first randomized controlled trial to test the efficacy of a group-based mentalization-based treatment for adolescents with BPD or subthreshold BPD. If the results confirm our hypothesis, this trial will add to the treatment options of cost-effective treatment of adolescent BPD. Clinicaltrials.gov NCT02068326 , February 19, 2014.

Systematic Review of Clinical Practice Guidelines for Failed Antidepressant Treatment Response in Major Depressive Disorder, Dysthymia, and Subthreshold Depression in Adults.

PubMed

MacQueen, Glenda; Santaguida, Pasqualina; Keshavarz, Homa; Jaworska, Natalia; Levine, Mitchell; Beyene, Joseph; Raina, Parminder

2017-01-01

This systematic review critically evaluated clinical practice guidelines (CPGs) for treating adults with major depressive disorder, dysthymia, or subthreshold or minor depression for recommendations following inadequate response to first-line treatment with selective serotonin reuptake inhibitors (SSRIs). Searches for CPGs (January 2004 to November 2014) in English included 7 bibliographic databases and grey literature sources using CPG and depression as the keywords. Two raters selected CPGs on depression with a national scope. Data extraction included definitions of adequate response and recommended treatment options. Two raters assessed quality using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. From 46,908 citations, 3167 were screened at full text. From these 21 CPG were applicable to adults in primary care and outpatient settings. Five CPGs consider patients with dysthymia or subthreshold or minor depression. None provides recommendations for those who do not respond to first-line SSRI treatment. For adults with MDD, most CPGs do not define an "inadequate response" or provide specific suggestions regarding how to choose alternative medications when switching to an alternative antidepressant. There is variability between CPGs in recommending combination strategies. AGREE II ratings for stakeholder involvement in CPG development, editorial independence, and rigor of development are domains in which depression guidelines are often less robust. About half of patients with depression require second-line treatment to achieve remission. Consistency and clarity in guidelines for second-line treatment of depression are therefore important for clinicians but lacking in most current guidelines. This may reflect a paucity of primary studies upon which to base conclusions.

Severity of complicated versus uncomplicated subthreshold depression: New evidence on the "Monotonicity Thesis" from the national comorbidity survey.

PubMed

Wakefield, Jerome C; Schmitz, Mark F

2017-04-01

"Complicated" subthreshold depression (CsD) includes at least one of six pathosuggestive "complicated" symptoms: >6 months duration, marked role impairment, sense of worthlessness, suicidal ideation, psychotic ideation, and psychomotor retardation. "Uncomplicated" subthreshold depression (UsD) has no complicated features. Whereas studies show that complicated (CMDD) versus uncomplicated (UMDD) major depression differ substantially in severity and prognosis, UsD and CsD severity has not been previously compared. This study evaluates UsD and CsD pathology validator levels and examines whether the complicated/uncomplicated distinction offers incremental concurrent validity over the standard number-of-symptoms dimension as a depression severity measure. Using nationally representative community data from the National Comorbidity Survey, seven depression lifetime history subgroups were identified: one MDD screener symptom (n=1432); UsD (n=430); CsD (n=611); UMDD (n=182); and CMDD with 5-6 symptoms (n=518), 7 symptoms (n=217), and 8-9 symptoms (n=291). Severity was evaluated using five concurrent pathology validators: suicide attempt, interference with life, help seeking, hospitalization, and generalized anxiety disorder. CsD validator levels are substantially higher than both UsD and UMDD levels, and similar to mild CMDD, disconfirming the "monotonicity thesis" that severity increase with symptom number. Complicated/uncomplicated status predicts severity, and when complicatedness is controlled, number of symptoms no longer predicts validator levels. Diagnoses were based on respondents' fallible retrospective symptom reports during a lay-administered structured interview, which may not yield diagnoses comparable to clinicians' assessments. CsD is more severe than UsD and comparable to mild MDD. Complicated status more validly indicates depression severity than the standard number-of-symptoms measure. Copyright © 2017 Elsevier B.V. All rights reserved.

Dural stimulation in rats causes BDNF-dependent priming to subthreshold stimuli including a migraine trigger

PubMed Central

Burgos-Vega, Carolina C.; Quigley, Lilyana D.; Avona, Amanda; Price, Theodore; Dussor, Gregory

2016-01-01

Migraine is one of the most common and most disabling disorders. Between attacks, migraine patients are otherwise normal but are sensitized to non-noxious events known as triggers. The purpose of these studies was to investigate whether a headache-like event causes sensitization, or priming, to subsequent subthreshold events. Interleukin-6 (IL-6) was applied to the rat cranial dura mater which produced cutaneous facial and hindpaw allodynia that lasted 24 hours. At 72-hours, IL-6 treated rats developed allodynia in response to dural stimulation with either a pH 6.8 or pH 7.0 solution and to a systemic nitric oxide (NO) donor, a well-known migraine trigger. Vehicle-treated rats did not respond to either pH stimulus nor to the NO donor, demonstrating that IL-6 exposure primes rats to subthreshold stimuli. Inhibitors of brain-derived neurotrophic factor (BDNF) signaling given either systemically or intracisternally 24-hours after IL-6 eliminated responses to dural pH stimulation at 72 hours. Additionally, intracisternal administration of BDNF without prior dural stimulation produced allodynia and once resolved, animals were primed to dural pH 6.8/pH 7.0 and a systemic NO donor. Finally, hindpaw IL-6 produced paw allodynia but not priming to paw injection of pH 7.0 at 72 hours demonstrating differences in priming depending on location. These data indicate that afferent input from the meninges produces BDNF-dependent priming of the dural nociceptive system. This primed state mimics the interictal period of migraine where attacks can be triggered by normally non-noxious events and suggests that BDNF-dependent plasticity may contribute to migraine. PMID:27841839

The folic acid combined with 17-β estradiol produces antidepressant-like actions in ovariectomized rats forced to swim.

PubMed

Molina-Hernández, Miguel; Téllez-Alcántara, N Patricia; Olivera-López, Jorge I; Jaramillo, M Teresa

2011-01-15

Folic acid or 17-β estradiol produces antidepressant effects, either alone or combined with several antidepressants. However, the antidepressant-like actions of folic acid combined with 17-β estradiol in the forced swimming test (FST) have not been tested before. Thus, in the present study, ovariectomized female rats received folic acid (5.0 nmol/i.c.v., P<0.05; 10.0 nmol/ i.c.v., P<0.05; or 50mg/kg, P<0.05, p.o.; 75.0; mg/kg, P<0.05, p.o.), or fluoxetine (20.0mg/kg, P<0.05; 25.0mg/kg, P<0.05) or 17-β estradiol (10.0 μg/rat, P<0.05; 20.0 μg/rat, P<0.05) and they displayed reduced immobility by increasing swimming behavior when they were tested in the FST. Combination of subthreshold doses of folic acid (2.5 nmol/i.c.v.; or 25.0mg/kg, p.o.) with subthreshold doses of 17-β estradiol (5.0 μg/rat, P<0.05) or with subthreshold doses of fluoxetine (15.0mg/kg, P<0.05) produced antidepressant-like actions. Ketanserin was used to evaluate the participation of the drugs used in the serotonergic pathway; ketanserin cancelled the antidepressant-like actions of the several combinations used. In conclusion, folic acid alone or combined with estradiol or fluoxetine in the FST reduced immobility in the FST. These antidepressant-like actions probably were due to modifications of the serotonergic system since swimming behavior was increased and these effects were cancelled by ketanserin. Copyright © 2010 Elsevier Inc. All rights reserved.

Adolescent outcomes of childhood attention-deficit/hyperactivity disorder in a diverse community sample

PubMed Central

Bussing, Regina; Mason, Dana M.; Bell, Lindsay; Porter, Phillip; Garvan, Cynthia

2010-01-01

Objective To describe adolescent outcomes of childhood attention deficit-/ hyperactivity disorder (ADHD) in a diverse community sample. Method ADHD screening of a school district sample of 1,615 students ages 5 to 11 years was followed by a case-control study 8 years later. High risk youths meeting full (n=94) and subthreshold (n=75) DSM-IV ADHD criteria were matched with demographically similar low risk peers (n=163). Outcomes domains included symptoms; functional impairment; quality of life; substance use; educational outcomes; and juvenile justice involvement. Results 44% of youths with childhood ADHD had not experienced remission. Compared to unaffected peers, adolescents with childhood ADHD were more likely to display oppositional defiant disorder (OR=12.9; 95% CI 5.6-30.0), anxiety/depression (OR=10.3; 95% CI 2.7-39.3), significant functional impairment (OR=3.4; 95% CI 1.7-6.9), reduced quality of life (OR=2.5, 95% CI 1.3-4.7), and to have been involved with juvenile justice (OR=3.1; 95% CI 1.0-9.1). Subthreshold ADHD, but not full ADHD, increased the risk of grade retention, whereas both conditions increased the risk of graduation failure. Oppositional defiant disorder (ODD), but not childhood ADHD, increased the risk of cannabis and alcohol use. None of the adolescent outcomes of childhood ADHD were moderated by gender, race or poverty. Conclusions ADHD heralds persistence of ADHD and comorbid symptoms into adolescence, as well as significant risks for functional impairment and juvenile justice involvement. Subthreshold ADHD symptoms typically do not qualify affected students for special educational interventions, yet increase the risk for adverse educational outcomes. Findings stress the importance of early ADHD recognition, especially its comorbid presentation with ODD, for prevention and intervention strategies. PMID:20494269

The meaning of (quality of) life in patients with eating disorders: a comparison of generic and disease-specific measures across diagnosis and outcome.

PubMed

Ackard, Diann M; Richter, Sara; Egan, Amber; Engel, Scott; Cronemeyer, Catherine L

2014-04-01

Compare general and disease-specific health-related quality of life (HRQoL) among female patients with an eating disorder (ED). Female patients (n = 221; 95.3% Caucasian; 94.0% never married) completed the Medical Outcome Short Form Health Survey (SF-36) and Eating Disorders Quality of Life (EDQoL) as part of a study of treatment outcomes. Multivariate regression models were used to compare HRQoL differences across initial ED diagnosis (85 AN-R, 19 AN-B/P, 27 BN, 90 EDNOS) and ED diagnostic classification at time of outcome assessment (140 no ED, 38 subthreshold ED, 43 full threshold ED). There were no significant differences across ED diagnosis at initial assessment on either of the SF-36 Component Summary scores. However, patients with AN-B/P scored poorer on the work/school EDQoL subscales than other ED diagnoses, and on the psychological EDQoL subscale compared to AN-R and EDNOS. At outcome assessment, comparisons across full threshold, subthreshold and no ED classification indicated that those with no ED reported better HRQoL than those with full threshold ED on the SF-36 Mental Components Summary and three of four EDQoL subscales. Furthermore, those with no ED reported better psychological HRQoL than those with subthreshold ED. Disease-specific HRQOL measures are important to use when comparing HRQoL in ED patients across treatment and outcome, and may have the sensitivity to detect meaningful differences by diagnosis more so than generic instruments. EDQoL scores from patients remitted from symptoms approach but do not reach scores for unaffected college females; thus, treatment should continue until quality of life is restored. Copyright © 2013 Wiley Periodicals, Inc.

Systematic Review of Clinical Practice Guidelines for Failed Antidepressant Treatment Response in Major Depressive Disorder, Dysthymia, and Subthreshold Depression in Adults

PubMed Central

MacQueen, Glenda; Santaguida, Pasqualina; Keshavarz, Homa; Jaworska, Natalia; Levine, Mitchell; Beyene, Joseph

2016-01-01

Objective: This systematic review critically evaluated clinical practice guidelines (CPGs) for treating adults with major depressive disorder, dysthymia, or subthreshold or minor depression for recommendations following inadequate response to first-line treatment with selective serotonin reuptake inhibitors (SSRIs). Method: Searches for CPGs (January 2004 to November 2014) in English included 7 bibliographic databases and grey literature sources using CPG and depression as the keywords. Two raters selected CPGs on depression with a national scope. Data extraction included definitions of adequate response and recommended treatment options. Two raters assessed quality using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument. Results: From 46,908 citations, 3167 were screened at full text. From these 21 CPG were applicable to adults in primary care and outpatient settings. Five CPGs consider patients with dysthymia or subthreshold or minor depression. None provides recommendations for those who do not respond to first-line SSRI treatment. For adults with MDD, most CPGs do not define an “inadequate response” or provide specific suggestions regarding how to choose alternative medications when switching to an alternative antidepressant. There is variability between CPGs in recommending combination strategies. AGREE II ratings for stakeholder involvement in CPG development, editorial independence, and rigor of development are domains in which depression guidelines are often less robust. Conclusions: About half of patients with depression require second-line treatment to achieve remission. Consistency and clarity in guidelines for second-line treatment of depression are therefore important for clinicians but lacking in most current guidelines. This may reflect a paucity of primary studies upon which to base conclusions. PMID:27554483

Dynamic, nonlinear feedback regulation of slow pacemaking by A-type potassium current in ventral tegmental area neurons.

PubMed

Khaliq, Zayd M; Bean, Bruce P

2008-10-22

We analyzed ionic currents that regulate pacemaking in dopaminergic neurons of the mouse ventral tegmental area by comparing voltage trajectories during spontaneous firing with ramp-evoked currents in voltage clamp. Most recordings were made in brain slice, with key experiments repeated using acutely dissociated neurons, which gave identical results. During spontaneous firing, net ionic current flowing between spikes was calculated from the time derivative of voltage multiplied by cell capacitance, signal-averaged over many firing cycles to enhance resolution. Net inward interspike current had a distinctive nonmonotonic shape, reaching a minimum (generally <1 pA) between -60 and -55 mV. Under voltage clamp, ramps over subthreshold voltages elicited a time- and voltage-dependent outward current that peaked near -55 mV. This current was undetectable with 5 mV/s ramps and increased steeply with depolarization rate over the range (10-50 mV/s) typical of natural pacemaking. Ramp-evoked subthreshold current was resistant to alpha-dendrotoxin, paxilline, apamin, and tetraethylammonium but sensitive to 4-aminopyridine and 0.5 mM Ba2+, consistent with A-type potassium current (I(A)). Same-cell comparison of currents elicited by various ramp speeds with natural spontaneous depolarization showed how the steep dependence of I(A) on depolarization rate results in small net inward currents during pacemaking. These results reveal a mechanism in which subthreshold I(A) is near zero at steady state, but is engaged at depolarization rates >10 mV/s to act as a powerful, supralinear feedback element. This feedback mechanism explains how net ionic current can be constrained to <1-2 pA but reliably inward, thus enabling slow, regular firing.

Whole School Behaviour Management and Perceptions of Behaviour Problems in Australian Primary Schools

ERIC Educational Resources Information Center

De Nobile, John; London, Teola; El Baba, Mariam

2015-01-01

Over the past decade and a half, whole school behaviour management systems have been implemented in many Australian schools in efforts to reduce undesirable behaviours and improve outcomes for students with behaviour problems. There is evidence in the literature suggesting that whole school approaches are more effective at managing student…

Association between slow-wave activity, cognition and behaviour in children with sleep-disordered breathing.

PubMed

Weichard, Aidan J; Walter, Lisa M; Hollis, Samantha L; Nixon, Gillian M; Davey, Margot J; Horne, Rosemary S C; Biggs, Sarah N

2016-09-01

It has been suggested that impaired dissipation of slow-wave activity (SWA) in children with sleep-disordered breathing (SDB) may be a potential mechanism for daytime dysfunction. We aimed to examine whether resolution of SDB resulted in normalisation of SWA dissipation and whether this was associated with improved cognition and behaviour. Children (aged 3-6 y) diagnosed with SDB and age-matched non-snoring control children were followed up for 3 y after a baseline study. At the follow-up, children were categorised into control (N = 13), resolved SDB (N = 15) and unresolved SDB (N = 14). Delta activity on the electroencephalogram over the sleep period was used to calculate SWA and a battery of cognitive assessments and behaviour questionnaires were conducted at both time points. There was no change in the average SWA between the baseline and follow-up and no differences between the groups. Cognitive and behavioural performance in the resolved group did not improve to control levels. However, decreased SWA at the beginning of the sleep period (β = -0.04, p = 0.002) and a decrease in obstructive apnoea-hypopnoea index (β = -2.2, p = 0.022) between the baseline and follow-up predicted improvements in measures of sustained attention. Increased SWA at the beginning of the sleep period between the baseline and follow-up predicted worsening of externalising behaviour (β = 0.02, p = 0.039). This study suggests that resolution of SDB is not associated with changes in the dissipation of SWA. However, the association between decreases in SWA and improvements in cognitive and behavioural outcomes suggest that irrespective of disease, children whose quantitative sleepiness improves have improved attention and reduced externalising behaviours. Copyright © 2016 Elsevier B.V. All rights reserved.

Development of Countermeasures to Aid Functional Egress from the Crew Exploration Vehicle Following Long Duration Spaceflight

NASA Technical Reports Server (NTRS)

Mulavara, Ajitkumar; Fiedler, Matthew; Kofman, Igor; Fisher, Elizabeth; Wood, Scott; Serrador, Jorge; Peters, Brian; Cohen, Helen; Reschke, Millard; Bloomberg, Jacob

2009-01-01

Astronauts experience disturbances in sensorimotor function following their return to Earth due to adaptive responses that occur during exposure to the microgravity conditions of space flight. As part of the Crew Exploration Vehicle design requirements, the crewmember adapted to the microgravity state may need to egress the vehicle within a few minutes for safety and operational reasons in various sea state conditions following a water landing. The act of emergency egress includes and is not limited to rapid motor control tasks (including both fine motor such as object manipulation and gross motor such as opening a hatch) and visual acuity tasks while maintaining spatial orientation and postural stability in time to escape safely. Exposure to even low frequency motions (0.2-2.0 Hz) induced by sea conditions surrounding a vessel can cause significant fine and gross motor control problems affecting critical functions. These motion frequencies coupled with the varying sea state conditions (frequencies ranging from 0.125-0.5 Hz) cause performance deficits by affecting the efficacy of motor and visual acuity dependent skills in tasks critical to emergency egress activities such as visual monitoring of displays, actuating discrete controls, operating auxiliary equipment and communicating with Mission Control and recovery teams. Thus, during exploration class missions the sensorimotor disturbances due to the crewmember's adaptation to microgravity may lead to disruption in the ability to maintain postural stability and perform functional egress tasks during the initial introduction to the Earth's gravitational environment. At present, the functional implication of the interactions between a debilitated crewmember during readaptation to Earth s gravity and the environmental constraints imposed by a water landing scenario is not defined and no operational countermeasure has been implemented to mitigate this risk. Stochastic resonance (SR) is a mechanism whereby noise can assist and hence enhance the response of neural systems to relevant, subthreshold sensory signals. Application of subthreshold stochastic resonance noise coupled to sensory input either through the proprioceptive, visual or vestibular sensory systems, has been shown to improve motor function. Crew members who have adapted to microgravity have acquired new sensorimotor strategies that take time to discard. We hypothesize that detection of time-critical subthreshold sensory signals will play a crucial role in improving strategic responses and thus the rate of skill re-acquisition will be faster, leading to faster recovery of function during their re-adaptation to Earth G. Therefore, we expect the use of stochastic resonance mechanisms will enhance the acquisition of new strategic abilities. This process should ensure rapid restoration of functional egress capabilities during the initial return to Earth G after prolonged space flight. Therefore, the overall goals of this project are to investigate performance of motor and visual tasks during varying sea state conditions and develop a countermeasure based on stochastic resonance that could be implemented to enhance sensorimotor capabilities with the aim of facilitating rapid adaptation to Earth s gravity, allowing rapid CEV egress on water in varying sea states following long-duration space flight.

Task-control of arousal and the effects of repeated unidirectional angular acceleration on human vestibular responses.

DOT National Transportation Integrated Search

1963-11-01

Subjects were exposed to a 10-day habituation series of 200 CW accelerations in total darkness while performing attention-demanding tasks. Decelerations were sub-threshold. Preliminary and post-tests indicated that slow-phase nystagmus and duration o...

Subthreshold Symptoms of Depression in Preadolescent Girls Are Stable and Predictive of Depressive Disorders

ERIC Educational Resources Information Center

Keenan, Kate; Hipwell, Alsion; Feng, Xin; Babinski, Dara; Hinze, Amanda; Rischall, Michal; Henneberger, Angela

2008-01-01

Symptoms of depression are investigated among 232 preadolescent girls to study if they were predictive and stable of depression. Findings show that early symptoms of depression among preadolescent girls predict depressive disorders. Implications for preventive measures are discussed.

Reduced contact resistance of a-IGZO thin film transistors with inkjet-printed silver electrodes

NASA Astrophysics Data System (ADS)

Chen, Jianqiu; Ning, Honglong; Fang, Zhiqiang; Tao, Ruiqiang; Yang, Caigui; Zhou, Yicong; Yao, Rihui; Xu, Miao; Wang, Lei; Peng, Junbiao

2018-04-01

In this study, high performance amorphous In–Ga–Zn–O (a-IGZO) TFTs were successfully fabricated with inkjet-printed silver source-drain electrodes. The results showed that increased channel thickness has an improving trend in the properties of TFTs due to the decreased contact resistance. Compared with sputtered silver TFTs, devices with printed silver electrodes were more sensitive to the thickness of active layer. Furthermore, the devices with optimized active layer showed high performances with a maximum saturation mobility of 8.73 cm2 · V‑1 · S‑1 and an average saturation mobility of 6.97 cm2 · V‑1 · S‑1, I on/I off ratio more than 107 and subthreshold swing of 0.28 V/decade, which were comparable with the analogous devices with sputtered electrodes.

Schottky barrier SOI-MOSFETs with high-k La2O3/ZrO2 gate dielectrics

PubMed Central

Henkel, C.; Abermann, S.; Bethge, O.; Pozzovivo, G.; Klang, P.; Stöger-Pollach, M.; Bertagnolli, E.

2011-01-01

Schottky barrier SOI-MOSFETs incorporating a La2O3/ZrO2 high-k dielectric stack deposited by atomic layer deposition are investigated. As the La precursor tris(N,N′-diisopropylformamidinato) lanthanum is used. As a mid-gap metal gate electrode TiN capped with W is applied. Processing parameters are optimized to issue a minimal overall thermal budget and an improved device performance. As a result, the overall thermal load was kept as low as 350, 400 or 500 °C. Excellent drive current properties, low interface trap densities of 1.9 × 1011 eV−1 cm−2, a low subthreshold slope of 70-80 mV/decade, and an ION/IOFF current ratio greater than 2 × 106 are obtained. PMID:21461054

Advanced analytical modeling of double-gate Tunnel-FETs - A performance evaluation

NASA Astrophysics Data System (ADS)

Graef, Michael; Hosenfeld, Fabian; Horst, Fabian; Farokhnejad, Atieh; Hain, Franziska; Iñíguez, Benjamín; Kloes, Alexander

2018-03-01

The Tunnel-FET is one of the most promising devices to be the successor of the standard MOSFET due to its alternative current transport mechanism, which allows a smaller subthreshold slope than the physically limited 60 mV/dec of the MOSFET. Recently fabricated devices show smaller slopes already but mostly not over multiple decades of the current transfer characteristics. In this paper the performance limiting effects, occurring during the fabrication process of the device, such as doping profiles and midgap traps are analyzed by physics-based analytical models and their performance limiting abilities are determined. Additionally, performance enhancing possibilities, such as hetero-structures and ambipolarity improvements are introduced and discussed. An extensive double-gate n-Tunnel-FET model is presented, which meets the versatile device requirements and shows a good fit with TCAD simulations and measurement data.

Subjective and Objective Binge Eating in Relation to Eating Disorder Symptomatology, Negative Affect, and Personality Dimensions

PubMed Central

Brownstone, Lisa M.; Bardone-Cone, Anna M.; Fitzsimmons-Craft, Ellen E.; Printz, Katherine S.; Le Grange, Daniel; Mitchell, James E.; Crow, Scott J.; Peterson, Carol B.; Crosby, Ross D.; Klein, Marjorie H.; Wonderlich, Stephen A.; Joiner, Thomas E.

2013-01-01

Objective The current study explored the clinical meaningfulness of distinguishing subjective (SBE) from objective binge eating (OBE) among individuals with threshold/subthreshold bulimia nervosa (BN). We examined relations between OBEs and SBEs and eating disorder symptoms, negative affect, and personality dimensions using both a group comparison and a continuous approach. Method Participants were 204 adult females meeting criteria for threshold/subthreshold BN who completed questionnaires related to disordered eating, affect, and personality. Results Group comparisons indicated that SBE and OBE groups did not significantly differ on eating disorder pathology or negative affect, but did differ on two personality dimensions (cognitive distortion and attentional impulsivity). Using the continuous approach, we found that frequencies of SBEs (not OBEs) accounted for unique variance in weight/shape concern, diuretic use frequency, depressive symptoms, anxiety, social avoidance, insecure attachment, and cognitive distortion. Discussion SBEs in the context of BN may indicate broader areas of psychopathology. PMID:23109272

Brain structural alterations associated with young women with subthreshold depression

PubMed Central

Li, Haijiang; Wei, Dongtao; Sun, Jiangzhou; Chen, Qunlin; Zhang, Qinglin; Qiu, Jiang

2015-01-01

Neuroanatomical abnormalities in patients with major depression disorder (MDD) have been attracted great research attention. However, the structural alterations associated with subthreshold depression (StD) remain unclear and, therefore, require further investigation. In this study, 42 young women with StD, and 30 matched non-depressed controls (NCs) were identified based on two-time Beck Depression Inventory scores. Whole-brain voxel-based morphometry (VBM) and region of interest method were used to investigate altered gray matter volume (GMV) and white matter volume (WMV) among a non-clinical sample of young women with StD. VBM results indicated that young women with StD showed significantly decreased GMV in the right inferior parietal lobule than NCs; increased GMV in the amygdala, posterior cingulate cortex, and precuneus; and increased WMV in the posterior cingulate cortex and precuneus. Together, structural alterations in specific brain regions, which are known to be involved in the fronto-limbic circuits implicated in depression may precede the occurrence of depressive episodes and influence the development of MDD. PMID:25982857

The electrical and interfacial properties of metal-high-k oxide-semiconductor field effect transistors with CeO2/HfO2 laminated gate dielectrics

NASA Astrophysics Data System (ADS)

Chang, Ingram Yin-ku; Chen, Chun-Heng; Chiu, Fu-Chien; Lee, Joseph Ya-min

2007-11-01

Metal-oxide-semiconductor field-effect transistors with CeO2/HfO2 laminated gate dielectrics were fabricated. The transistors have a subthreshold slope of 74.9mV/decade. The interfacial properties were measured using gated diodes. The surface state density Dit was 9.78×1011cm-2eV-1. The surface-recombination velocity (s0) and the minority carrier lifetime in the field-induced depletion region (τ0,FIJ) measured from the gated diode were about 6.11×103cm /s and 1.8×10-8s, respectively. The effective capture cross section of surface state (σs) extracted using the subthreshold-swing measurement and the gated diode was about 7.69×10-15cm2. The effective electron mobility of CeO2/HfO2 laminated gated transistors was determined to be 212cm2/Vs.

Simulation of planar single-gate Si tunnel FET with average subthreshold swing of less than 60 mV/decade for 0.3 V operation

NASA Astrophysics Data System (ADS)

Kukita, Kentaro; Uechi, Tadayoshi; Shimokawa, Junji; Goto, Masakazu; Yokota, Yoshinori; Kawanaka, Shigeru; Tanamoto, Tetsufumi; Tanimoto, Hiroyoshi; Takagi, Shinichi

2018-04-01

Planar single-gate (SG) silicon (Si) tunnel field effect transistors (TFETs) are attracting interest for ultra-low voltage operation and CMOS applications. For the achievement of subthreshold swing (S.S.) less than thermal limit of Si MOSFETs (S.S. = 60 mV/decade at 300 K), previous studies have proposed the formation of a pocket region, which needs very difficult implantation process. In this work, a planar SG Si TFET without pocket was proposed by using the technology computer-aided design (TCAD) simulations. An average S.S. of less than 60 mV/decade for 0.3 V (= V gs = V ds) operation was obtained. It is found that both low average S.S. (= 27.8 mV/decade) and high on-current I on (= 3.8 µA/µm) are achieved without pocket doping by scaling the equivalent oxide thickness (EOT) and increasing the gate-to-source overlap length L ov.

Intracellular determinants of hippocampal CA1 place and silent cell activity in a novel environment

PubMed Central

Epsztein, Jérôme; Brecht, Michael; Lee, Albert K.

2011-01-01

Summary For each environment a rodent has explored, its hippocampus contains a map consisting of a unique subset of neurons, called place cells, that have spatially-tuned spiking there, with the remaining neurons being essentially silent. Using whole-cell recording in freely moving rats exploring a novel maze, we observed differences in intrinsic cellular properties and input-based subthreshold membrane potential levels underlying this division into place and silent cells. Compared to silent cells, place cells had lower spike thresholds and peaked versus flat subthreshold membrane potentials as a function of animal location. Both differences were evident from the beginning of exploration. Additionally, future place cells exhibited higher burst propensity before exploration. Thus, internal settings appear to predetermine which cells will represent the next novel environment encountered. Furthermore, place cells fired spatially-tuned bursts with large, putatively calcium-mediated depolarizations that could trigger plasticity and stabilize the new map for long-term storage. Our results provide new insight into hippocampal memory formation. PMID:21482360

Sub-threshold panic attacks and agoraphobic avoidance increase comorbidity of mental disorders: results from an adult general population sample.

PubMed

Pané-Farré, Christiane A; Fenske, Kristin; Stender, Jan P; Meyer, Christian; John, Ulrich; Rumpf, Hans-Jürgen; Hapke, Ulfert; Hamm, Alfons O

2013-06-01

Full-blown panic attacks are frequently associated with other mental disorders. Most comorbidity analyses did not discriminate between isolated panic attacks vs. panic attacks that occurred in the context of a panic disorder and rarely evaluated the impact of comorbid agoraphobia. Moreover, there are no larger scale epidemiological studies regarding the influence of sub-threshold panic attacks. 4075 German-speaking respondents aged 18-64 were interviewed using the fully structured Munich Composite International Diagnostic Interview. Limited symptom attacks, isolated panic attacks, and panic disorder were associated with other lifetime DSM-IV disorders with monotonically increasing odds and increasing tendency for multiple comorbidities across the three groups. The presence of agoraphobia was associated with more frequent comorbidity in all panic subgroups and also in persons who never experienced panic attacks. The present study suggests that populations with isolated or limited symptom should be carefully attended to in clinical practice, especially if agoraphobia is present. Copyright © 2013 Elsevier Ltd. All rights reserved.

Taste aversion learning produced by combined treatment with subthreshold radiation and lithium chloride

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

Rabin, B.M.; Hunt, W.A.; Lee, J.

1987-08-01

These experiments were designed to determine whether treatment with two subthreshold doses of radiation or lithium chloride, either alone or in combination, could lead to taste aversion learning. The first experiment determined the thresholds for a radiation-induced taste aversion at 15-20 rad and for lithium chloride at 0.30-0.45 mEq/kg. In the second experiment it was shown that exposing rats to two doses of 15 rad separated by up to 3 hr produced a taste aversion. Treatment with two injections of lithium chloride (0.30 mEq/kg) did not produce a significant reduction in preference. Combined treatment with radiation and lithium chloride didmore » produce a taste aversion when the two treatments were administered within 1 hr of each other. The results are discussed in terms of the implications of these findings for understanding the nature of the unconditioned stimuli leading to the acquisition of a conditioned taste aversion.« less

Sub-kT/q Subthreshold-Slope Using Negative Capacitance in Low-Temperature Polycrystalline-Silicon Thin-Film Transistor

PubMed Central

Park, Jae Hyo; Jang, Gil Su; Kim, Hyung Yoon; Seok, Ki Hwan; Chae, Hee Jae; Lee, Sol Kyu; Joo, Seung Ki

2016-01-01

Realizing a low-temperature polycrystalline-silicon (LTPS) thin-film transistor (TFT) with sub-kT/q subthreshold slope (SS) is significantly important to the development of next generation active-matrix organic-light emitting diode displays. This is the first time a sub-kT/q SS (31.44 mV/dec) incorporated with a LTPS-TFT with polycrystalline-Pb(Zr,Ti)O3 (PZT)/ZrTiO4 (ZTO) gate dielectrics has been demonstrated. The sub-kT/q SS was observed in the weak inversion region at −0.5 V showing ultra-low operating voltage with the highest mobility (250.5 cm2/Vsec) reported so far. In addition, the reliability of DC negative bias stress, hot carrier stress and self-heating stress in LTPS-TFT with negative capacitance was investigated for the first time. It was found that the self-heating stress showed accelerated SS degradation due to the PZT Curie temperature. PMID:27098115

Seismicity of Afghanistan and vicinity

USGS Publications Warehouse

Dewey, James W.

2006-01-01

This publication describes the seismicity of Afghanistan and vicinity and is intended for use in seismic hazard studies of that nation. Included are digital files with information on earthquakes that have been recorded in Afghanistan and vicinity through mid-December 2004. Chapter A provides an overview of the seismicity and tectonics of Afghanistan and defines the earthquake parameters included in the 'Summary Catalog' and the 'Summary of Macroseismic Effects.' Chapter B summarizes compilation of the 'Master Catalog' and 'Sub-Threshold Catalog' and documents their formats. The 'Summary Catalog' itself is presented as a comma-delimited ASCII file, the 'Summary of Macroseismic Effects' is presented as an html file, and the 'Master Catalog' and 'Sub-Threshold Catalog' are presented as flat ASCII files. Finally, this report includes as separate plates a digital image of a map of epicenters of earthquakes occurring since 1964 (Plate 1) and a representation of areas of damage or strong shaking from selected past earthquakes in Afghanistan and vicinity (Plate 2).

Taste aversion learning produced by combined treatment with subthreshold radiation and lithium chloride.

PubMed

Rabin, B M; Hunt, W A; Lee, J

1987-08-01

These experiments were designed to determine whether treatment with two subthreshold doses of radiation or lithium chloride, either alone or in combination, could lead to taste aversion learning. The first experiment determined the thresholds for a radiation-induced taste aversion at 15-20 rad and for lithium chloride at 0.30-0.45 mEq/kg. In the second experiment it was shown that exposing rats to two doses of 15 rad separated by up to 3 hr produced a taste aversion. Treatment with two injections of lithium chloride (0.30 mEq/kg) did not produce a significant reduction in preference. Combined treatment with radiation and lithium chloride did produce a taste aversion when the two treatments were administered within 1 hr of each other. The results are discussed in terms of the implications of these findings for understanding the nature of the unconditioned stimuli leading to the acquisition of a conditioned taste aversion.

Emergence of Orientation Selectivity in the Mammalian Visual Pathway

PubMed Central

Scholl, Benjamin; Tan, Andrew Y. Y.; Corey, Joseph

2013-01-01

Orientation selectivity is a property of mammalian primary visual cortex (V1) neurons, yet its emergence along the visual pathway varies across species. In carnivores and primates, elongated receptive fields first appear in V1, whereas in lagomorphs such receptive fields emerge earlier, in the retina. Here we examine the mouse visual pathway and reveal the existence of orientation selectivity in lateral geniculate nucleus (LGN) relay cells. Cortical inactivation does not reduce this orientation selectivity, indicating that cortical feedback is not its source. Orientation selectivity is similar for LGN relay cells spiking and subthreshold input to V1 neurons, suggesting that cortical orientation selectivity is inherited from the LGN in mouse. In contrast, orientation selectivity of cat LGN relay cells is small relative to subthreshold inputs onto V1 simple cells. Together, these differences show that although orientation selectivity exists in visual neurons of both rodents and carnivores, its emergence along the visual pathway, and thus its underlying neuronal circuitry, is fundamentally different. PMID:23804085

Membrane Potential Dynamics of CA1 Pyramidal Neurons During Hippocampal Ripples in Awake Mice

PubMed Central

Hulse, Brad K.; Moreaux, Laurent C.; Lubenov, Evgueniy V.; Siapas, Athanassios G.

2016-01-01

Ripples are high-frequency oscillations associated with population bursts in area CA1 of the hippocampus that play a prominent role in theories of memory consolidation. While spiking during ripples has been extensively studied, our understanding of the subthreshold behavior of hippocampal neurons during these events remains incomplete. Here, we combine in vivo whole-cell and multisite extracellular recordings to characterize the membrane potential dynamics of identified CA1 pyramidal neurons during ripples. We find that the subthreshold depolarization during ripples is uncorrelated with the net excitatory input to CA1, while the post-ripple hyperpolarization varies proportionately. This clarifies the circuit mechanism keeping most neurons silent during ripples. On a finer time scale, the phase delay between intracellular and extracellular ripple oscillations varies systematically with membrane potential. Such smoothly varying delays are inconsistent with models of intracellular ripple generation involving perisomatic inhibition alone. Instead, they suggest that ripple-frequency excitation leading inhibition shapes intracellular ripple oscillations. PMID:26889811

Subthreshold depression and subjective cognitive complaints in Parkinson's disease.

PubMed

Santangelo, G; Vitale, C; Trojano, L; Angrisano, M G; Picillo, M; Errico, D; Agosti, V; Grossi, D; Barone, P

2014-03-01

Subthreshold depression (SubD) is characterized by clinically relevant depressive symptoms not meeting criteria for major depression. The possible association of SubD with subjective cognitive complaints and/or objective cognitive impairments was investigated in a sample of consecutive, non-demented Parkinson's disease (PD) outpatients. Amongst 115 patients, SubD was identified in 30 patients, major depression in 33; 36 patients were classified as non-depressed. Enrolled patients were administered tests and questionnaires validated in PD for assessing objective and subjective cognitive dysfunctions. On objective cognitive measures SubD patients did not differ from non-depressed patients, whereas depressed patients achieved significantly lower scores than the other two groups. SubD and depressed patients reported more cognitive complaints than non-depressed patients. SubD is a non-motor aspect of PD that is not related to objective cognitive deficits but is associated with subjective cognitive complaints, thus impacting on patients' well-being. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

Noise assisted pattern fabrication

NASA Astrophysics Data System (ADS)

Roy, Tanushree; Agarwal, V.; Singh, B. P.; Parmananda, P.

2018-04-01

Pre-selected patterns on an n-type Si surface are fabricated by electrochemical etching in the presence of a weak optical signal. The constructive role of noise, namely, stochastic resonance (SR), is exploited for these purposes. SR is a nonlinear phenomenon wherein at an optimal amplitude of noise, the information transfer from weak input sub-threshold signals to the system output is maximal. In the present work, the amplitude of internal noise was systematically regulated by varying the molar concentration of hydrofluoric acid (HF) in the electrolyte. Pattern formation on the substrate for two different amplitudes (25 ± 2 and 11 ± 1 mW) of the optical template (sub-threshold signal) was considered. To quantify the fidelity/quality of pattern formation, the spatial cross-correlation coefficient (CCC) between the constructed pattern and the template of the applied signal was calculated. The maximum CCC is obtained for the pattern formed at an optimal HF concentration, indicating SR. Simulations, albeit using external noise, on a spatial array of coupled FitzHugh-Nagumo oscillators revealed similar results.

How do individuals' health behaviours respond to an increase in the supply of health care? Evidence from a natural experiment.

PubMed

Fichera, Eleonora; Gray, Ewan; Sutton, Matt

2016-06-01

The efficacy of the management of long-term conditions depends in part on whether healthcare and health behaviours are complements or substitutes in the health production function. On the one hand, individuals might believe that improved health care can raise the marginal productivity of their own health behaviour and decide to complement health care with additional effort in healthier behaviours. On the other hand, health care can lower the cost of unhealthy behaviours by compensating for their negative effects. Individuals may therefore reduce their effort in healthier lifestyles. Identifying which of these effects prevails is complicated by the endogenous nature of treatment decisions and individuals' behavioural responses. We explore whether the introduction in 2004 of the Quality and Outcomes Framework (QOF), a financial incentive for family doctors to improve the quality of healthcare, affected the population's weight, smoking and drinking behaviours by applying a sharp regression discontinuity design to a sample of 32,102 individuals in the Health Survey for England (1997-2009). We find that individuals with the targeted health conditions improved their lifestyle behaviours. This complementarity was only statistically significant for smoking, which reduced by 0.7 cigarettes per person per day, equal to 18% of the mean. We investigate whether this change was attributable to the QOF by testing for other discontinuity points, including the introduction of a smoking ban in 2007 and changes to the QOF in 2006. We also examine whether medication and smoking cessation advice are potential mechanisms and find no statistically significant discontinuities for these aspects of health care supply. Our results suggest that a general improvement in healthcare generated by provider incentives can have positive unplanned effects on patients' behaviours. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Self-Monitoring vs. Implementation Intentions: a Comparison of Behaviour Change Techniques to Improve Sleep Hygiene and Sleep Outcomes in Students.

PubMed

Mairs, Lucinda; Mullan, Barbara

2015-10-01

This study seeks to investigate and compare the efficacy of self-monitoring and implementation intentions-two post-intentional behaviour change techniques-for improving sleep hygiene behaviours and sleep outcomes in university students. Seventy-two undergraduate students completed baseline measures of four sleep hygiene behaviours (making the sleep environment restful, avoiding going to bed hungry/thirsty, avoiding stress/anxiety-provoking activities near bed time and avoiding caffeine in the evening), as well as the Pittsburgh sleep quality index (PSQI) and the insomnia severity index (ISI). Participants were randomly assigned to an active-control diary-keeping, self-monitoring condition or completed implementation intentions for each behaviour. Post-intervention measurement was completed 2 weeks after baseline. Repeated measures analyses of variance found significant main effects of time for improvements in making the sleep environment restful and avoiding going to bed hungry or thirsty, as well as PSQI and ISI scores. Non-significant interactions suggested no group differences on any variable, except for increasing avoidance of stress and anxiety-provoking activities before bed time, for which only implementation intentions were found to be effective. Attrition was higher amongst self-monitoring participants. Both self-monitoring and implementation intentions appear to be promising behaviour change techniques for improving sleep hygiene and sleep. Future research should examine the acceptability of the two behaviour change techniques and the relationship with differential attrition, as well as effect size variations according to behaviour and technique. Researchers should investigate potential additive or interactive effects of the techniques, as they could be utilised in a complementary manner to target different processes in effecting behaviour change.

Application of self-efficacy theory in dental clinical practice.

PubMed

Kakudate, N; Morita, M; Fukuhara, S; Sugai, M; Nagayama, M; Kawanami, M; Chiba, I

2010-11-01

In clinical practice, self-efficacy refers to how certain a patient feels about his or her ability to take the necessary action to improve the indicators and maintenance of health. It is assumed that the prognosis for patient behaviour can be improved by assessing the proficiency of their self-efficacy through providing psychoeducational instructions adapted for individual patients, and promoting behavioural change for self-care. Therefore, accurate assessment of self-efficacy is an important key in daily clinical preventive care. The previous research showed that the self-efficacy scale scores predicted patient behaviour in periodontal patients and mother's behaviour in paediatric dental practice. Self-efficacy belief is constructed from four principal sources of information: enactive mastery experience, vicarious experience, verbal persuasion, and physiological and affective states. Thus, self-efficacy can be enhanced by the intervention exploiting these sources. The previous studies revealed that behavioural interventions to enhance self-efficacy improved oral-care behaviour of patients. Therefore, assessment and enhancement of oral-care specific self-efficacy is important to promote behaviour modification in clinical dental practice. However, more researches are needed to evaluate the suitability of the intervention method. © 2010 John Wiley & Sons A/S.

Preschool children's response to behavioural parent training and parental predictors of outcome in routine clinical care.

PubMed

van der Veen-Mulders, Lianne; Hoekstra, Pieter J; Nauta, Maaike H; van den Hoofdakker, Barbara J

2018-01-01

To investigate the effectiveness of behavioral parent training (BPT) for preschool children with disruptive behaviours and to explore parental predictors of response. Parents of 68 preschool children, aged between 2.7 and 5.9 years, participated in BPT. We evaluated the changes in children's behaviour after BPT with a one group pretest-posttest design, using a waiting period for a double pretest. Outcome was based on parents' reports of the intensity and number of behaviour problems on the Eyberg Child Behavior Inventory. Predictor variables included parents' attention-deficit/hyperactivity disorder symptoms, antisocial behaviours, and alcohol use, and maternal parenting self-efficacy and disciplining. Mother-reported child behaviour problems did not change in the waiting period but improved significantly after BPT (d = 0.63). High levels of alcohol use by fathers and low levels of maternal ineffective disciplining were each associated with somewhat worse outcome. BPT under routine care conditions clearly improves disruptive behaviours in preschool children. Mothers who consider themselves as inadequate in disciplining and mothers whose partners do not consume high levels of alcohol report the largest improvements. Copyright © 2017 John Wiley & Sons, Ltd.

Type A behaviour and the healthy individual.

PubMed

Ivancevich, J M; Matteson, M T

1988-03-01

The Type A behaviour pattern (TABP) is an interesting and controversial construct that has generated debate, empirical testing, and behavioural modification attempts. TABP is depicted as consisting of impatient or hurried behaviour, a strong orientation toward work responsibilities and task completion, and intensive competitive behaviour in situations that involve evaluation. Recently, the importance of what is called the anger/hostility dimension has been emphasized in research studies. After more than two decades of debate, testing, and attempting to modify the entire TABP there is now a growing acceptance of the proposition that a major overhaul or change in the TABP is not necessary or even feasible. The Type A person is also now being presented as possessing many desirable characteristics and healthy behaviours that are worth reinforcing. The present paper provides a brief review of the contradictory research evidence surrounding the Type A syndrome. Theorists, researchers, and organizational practitioners are encouraged to seek improvements in understanding the TABP through improved assessment and how it can be modified in generally healthy individuals. A theoretical model to guide improvement efforts in measurement and intervention is provided as a viable framework to examine causal pathways between antecedents, Type A core behaviours, responses, and consequences.

Room for improvement? Leadership, innovation culture and uptake of quality improvement methods in general practice.

PubMed

Apekey, Tanefa A; McSorley, Gerry; Tilling, Michelle; Siriwardena, A Niroshan

2011-04-01

Leadership and innovation are currently seen as essential elements for the development and maintenance of high-quality care. Little is known about the relationship between leadership and culture of innovation and the extent to which quality improvement methods are used in general practice. This study aimed to assess the relationship between leadership behaviour, culture of innovation and adoption of quality improvement methods in general practice. Self-administered postal questionnaires were sent to general practitioner quality improvement leads in one county in the UK between June and December 2007. The questionnaire consisted of background information, a 12-item scale to assess leadership behaviour, a seven-dimension self-rating scale for culture of innovation and questions on current use of quality improvement tools and techniques. Sixty-three completed questionnaires (62%) were returned. Leadership behaviours were not commonly reported. Most practices reported a positive culture of innovation, featuring relationship most strongly, followed by targets and information but rated lower on other dimensions of rewards, risk and resources. There was a significant positive correlation between leadership behaviour and the culture of innovation (r = 0.57; P < 0.001). Apart from clinical audit and significant event analysis, quality improvement methods were not adopted by most participating practices. Leadership behaviours were infrequently reported and this was associated with a limited culture of innovation in participating general practices. There was little use of quality improvement methods beyond clinical and significant event audit. Practices need support to enhance leadership skills, encourage innovation and develop quality improvement skills if improvements in health care are to accelerate. © 2010 Blackwell Publishing Ltd.

Psychiatric Correlates of Nonsuicidal Cutting Behaviors in an Adolescent Inpatient Sample

ERIC Educational Resources Information Center

Swenson, Lance P.; Spirito, Anthony; Dyl, Jennifer; Kittler, Jennifer; Hunt, Jeffrey I.

2008-01-01

This archival study of 288 adolescent psychiatric inpatients examined the psychiatric correlates of cutting behavior. Participants were categorized into Threshold cutters (n = 61), Subthreshold cutters (n = 43), and Noncutters (n = 184). Groups were compared on psychiatric diagnoses, suicidality, and self-reported impairment. Results demonstrated…

Adult Autism Subthreshold Spectrum (AdAS Spectrum): Validation of a questionnaire investigating subthreshold autism spectrum.

PubMed

Dell'Osso, L; Gesi, C; Massimetti, E; Cremone, I M; Barbuti, M; Maccariello, G; Moroni, I; Barlati, S; Castellini, G; Luciano, M; Bossini, L; Rocchetti, M; Signorelli, M; Aguglia, E; Fagiolini, A; Politi, P; Ricca, V; Vita, A; Carmassi, C; Maj, M

2017-02-01

Increasing literature has shown the usefulness of a dimensional approach to autism. The present study aimed to determine the psychometric properties of the Adult Autism Subthreshold Spectrum (AdAS Spectrum), a new questionnaire specifically tailored to assess subthreshold forms of autism spectrum disorder (ASD) in adulthood. 102 adults endorsing at least one DSM-5 symptom criterion for ASD (ASDc), 143 adults diagnosed with a feeding and eating disorder (FED), and 160 subjects with no mental disorders (CTL), were recruited from 7 Italian University Departments of Psychiatry and administered the following: SCID-5, Autism-Spectrum Quotient (AQ), Ritvo Autism and Asperger Diagnostic Scale 14-item version (RAADS-14), and AdAS Spectrum. The AdAS Spectrum demonstrated excellent internal consistency for the total score (Kuder-Richardson's coefficient=.964) as well as for five out of seven domains (all coefficients>.80) and sound test-retest reliability (ICC=.976). The total and domain AdAS Spectrum scores showed a moderate to strong (>.50) positive correlation with one another and with the AQ and RAADS-14 total scores. ASDc subjects reported significantly higher AdAS Spectrum total scores than both FED (p<.001) and CTL (p<.001), and significantly higher scores on the Childhood/adolescence, Verbal communication, Empathy, Inflexibility and adherence to routine, and Restricted interests and rumination domains (all p<.001) than FED, while on all domains compared to CTL. CTL displayed significantly lower total and domain scores than FED (all p<.001). A significant effect of gender emerged for the Hyper- and hyporeactivity to sensory input domain, with women showing higher scores than men (p=.003). A Diagnosis* Gender interaction was also found for the Verbal communication (p=.019) and Empathy (p=.023) domains. When splitting the ASDc in subjects with one symptom criterion (ASD 1 ) and those with a ASD, and the FED in subjects with no ASD symptom criteria (FED 0 ) and those with one ASD symptom criterion (FED 1 ) , a gradient of severity in AdAS Spectrum scores from CTL subjects to ASD patients, across FED 0 , ASD 1 , FED 1 was shown. The AdAS Spectrum showed excellent internal consistency and test-retest reliability and strong convergent validity with alternative dimensional measures of ASD. The questionnaire performed differently among the three diagnostic groups and enlightened some significant effects of gender in the expression of autistic traits. Copyright © 2016 Elsevier Inc. All rights reserved.

A review of health behaviour theories: how useful are these for developing interventions to promote long-term medication adherence for TB and HIV/AIDS?

PubMed Central

Munro, Salla; Lewin, Simon; Swart, Tanya; Volmink, Jimmy

2007-01-01

Background Suboptimal treatment adherence remains a barrier to the control of many infectious diseases, including tuberculosis and HIV/AIDS, which contribute significantly to the global disease burden. However, few of the many interventions developed to address this issue explicitly draw on theories of health behaviour. Such theories could contribute to the design of more effective interventions to promote treatment adherence and to improving assessments of the transferability of these interventions across different health issues and settings. Methods This paper reviews behaviour change theories applicable to long-term treatment adherence; assesses the evidence for their effectiveness in predicting behaviour change; and examines the implications of these findings for developing strategies to improve TB and HIV/AIDS medication adherence. We searched a number of electronic databases for theories of behaviour change. Eleven theories were examined. Results Little empirical evidence was located on the effectiveness of these theories in promoting adherence. However, several models have the potential to both improve understanding of adherence behaviours and contribute to the design of more effective interventions to promote adherence to TB and HIV/AIDS medication. Conclusion Further research and analysis is needed urgently to determine which models might best improve adherence to long-term treatment regimens. PMID:17561997

1-D Compression Behaviour of Acid Sulphate Soils Treated with Alkali-Activated Slag

PubMed Central

Islam, Shahidul; Haque, Asadul; Bui, Ha Hong

2016-01-01

Improvements of soft soils by mechanically mixing cementitious additives have been widely practised for construction of infrastructure. Mixing of additives improves strength and compressibility properties of soils through the development of soil structure. This study investigates the 1-D compression behaviour of alkali-activated slag treated acid sulphate soils (ASS) cured up to 365 days. The void ratio-logarithm of pressure (e-logσ′) behaviour of treated ASS, including the destructuration behaviour, with additive contents and curing time have been analysed. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses have been undertaken to explain the observed variations of the 1-D compression behaviour. This paper presents the results of these analyses in view of obtaining an insight into the 1-D compression behaviour of treated ASS with the help of mineralogical analysis. PMID:28773415

1-D Compression Behaviour of Acid Sulphate Soils Treated with Alkali-Activated Slag.

PubMed

Islam, Shahidul; Haque, Asadul; Bui, Ha Hong

2016-04-15

Improvements of soft soils by mechanically mixing cementitious additives have been widely practised for construction of infrastructure. Mixing of additives improves strength and compressibility properties of soils through the development of soil structure. This study investigates the 1-D compression behaviour of alkali-activated slag treated acid sulphate soils (ASS) cured up to 365 days. The void ratio-logarithm of pressure (e-logσ') behaviour of treated ASS, including the destructuration behaviour, with additive contents and curing time have been analysed. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses have been undertaken to explain the observed variations of the 1-D compression behaviour. This paper presents the results of these analyses in view of obtaining an insight into the 1-D compression behaviour of treated ASS with the help of mineralogical analysis.

How behavioural science can contribute to health partnerships: the case of The Change Exchange.

PubMed

Byrne-Davis, Lucie M T; Bull, Eleanor R; Burton, Amy; Dharni, Nimarta; Gillison, Fiona; Maltinsky, Wendy; Mason, Corina; Sharma, Nisha; Armitage, Christopher J; Johnston, Marie; Byrne, Ged J; Hart, Jo K

2017-06-12

Health partnerships often use health professional training to change practice with the aim of improving quality of care. Interventions to change practice can learn from behavioural science and focus not only on improving the competence and capability of health professionals but also their opportunity and motivation to make changes in practice. We describe a project that used behavioural scientist volunteers to enable health partnerships to understand and use the theories, techniques and assessments of behavioural science. This paper outlines how The Change Exchange, a collective of volunteer behavioural scientists, worked with health partnerships to strengthen their projects by translating behavioural science in situ. We describe three case studies in which behavioural scientists, embedded in health partnerships in Uganda, Sierra Leone and Mozambique, explored the behaviour change techniques used by educators, supported knowledge and skill development in behaviour change, monitored the impact of projects on psychological determinants of behaviour and made recommendations for future project developments. Challenges in the work included having time and space for behavioural science in already very busy health partnership schedules and the difficulties in using certain methods in other cultures. Future work could explore other modes of translation and further develop methods to make them more culturally applicable. Behavioural scientists could translate behavioural science which was understood and used by the health partnerships to strengthen their project work.

Planning, Practising and Prioritising Wellness through an Integrative Behaviour Change Plan

ERIC Educational Resources Information Center

Crossman, Joanne M.

2016-01-01

Study objective: To describe a successful approach to teaching principles and practices of behaviour change through a behaviour change plan (BCP) initiative to improve personal health while advancing health knowledge and general education intellectual skills. Students' perspectives of obstacles, behaviours important towards goal attainment and the…

Randomised trial of biofeedback training for encopresis.

PubMed Central

van der Plas, R N; Benninga, M A; Redekop, W K; Taminiau, J A; Büller, H A

1996-01-01

AIMS: To evaluate biofeedback training in children with encopresis and the effect on psychosocial function. DESIGN: Prospective controlled randomised study. PATIENT INTERVENTIONS: A multimodal treatment of six weeks. Children were randomised into two groups. Each group received dietary and toilet advice, enemas, oral laxatives, and anorectal manometry. One group also received five biofeedback training sessions. MAIN OUTCOME MEASURES: Successful treatment was defined as less than two episodes of encopresis, regular bowel movements, and no laxatives. Psychosocial function after treatment was assessed using the Child Behaviour Checklist. RESULTS: Children given laxatives and biofeedback training had higher success rates than those who received laxatives alone (39% v 19%) at the end of the intervention period. At 12 and 18 months, however, approximately 50% of children in each group were successfully treated. Abnormal behaviour scores were initially observed in 35% of children. Most children had improved behaviour scores six months after treatment. Children with an initial abnormal behaviour score who were successfully treated had a significant improvement in their behavioural profiles. CONCLUSIONS: Biofeedback training had no additional effect on the success rate or behaviour scores. Psychosocial problems are present in a subgroup of children with encopresis. The relation between successful treatment and improvement in behavioural function supports the idea that encopresis has an aetiological role in the occurrence and maintenance of behavioural problems in children with encopresis. PMID:8957948

Complex adaptive systems: a tool for interpreting responses and behaviours.

PubMed

Ellis, Beverley

2011-01-01

Quality improvement is a priority for health services worldwide. There are many barriers to implementing change at the locality level and misinterpreting responses and behaviours can effectively block change. Electronic health records will influence the means by which knowledge and information are generated and sustained among those operating quality improvement programmes. To explain how complex adaptive system (CAS) theory provides a useful tool and new insight into the responses and behaviours that relate to quality improvement programmes in primary care enabled by informatics. Case studies in two English localities who participated in the implementation and development of quality improvement programmes. The research strategy included purposefully sampled case studies, conducted within a social constructionist ontological perspective. Responses and behaviours of quality improvement programmes in the two localities include both positive and negative influences associated with a networked model of governance. Pressures of time, resources and workload are common issues, along with the need for education and training about capturing, coding, recording and sharing information held within electronic health records to support various information requirements. Primary care informatics enables information symmetry among those operating quality improvement programmes by making some aspects of care explicit, allowing consensus about quality improvement priorities and implementable solutions.

Training practitioners to deliver opportunistic multiple behaviour change counselling in primary care: a cluster randomised trial.

PubMed

Butler, Christopher C; Simpson, Sharon A; Hood, Kerenza; Cohen, David; Pickles, Tim; Spanou, Clio; McCambridge, Jim; Moore, Laurence; Randell, Elizabeth; Alam, M Fasihul; Kinnersley, Paul; Edwards, Adrian; Smith, Christine; Rollnick, Stephen

2013-03-19

To evaluate the effect of training primary care health professionals in behaviour change counselling on the proportion of patients self reporting change in four risk behaviours (smoking, alcohol use, exercise, and healthy eating). Cluster randomised trial with general practices as the unit of randomisation. General practices in Wales. 53 general practitioners and practice nurses from 27 general practices (one each at all but one practice) recruited 1827 patients who screened positive for at least one risky behaviour. Behaviour change counselling was developed from motivational interviewing to enable clinicians to enhance patients' motivation to change health related behaviour. Clinicians were trained using a blended learning programme called Talking Lifestyles. Proportion of patients who reported making beneficial changes in at least one of the four risky behaviours at three months. 1308 patients from 13 intervention and 1496 from 14 control practices were approached: 76% and 72% respectively agreed to participate, with 831 (84%) and 996 (92%) respectively screening eligible for an intervention. There was no effect on the primary outcome (beneficial change in behaviour) at three months (362 (44%) v 404 (41%), odds ratio 1.12 (95% CI 0.90 to 1.39)) or on biochemical or biometric measures at 12 months. More patients who had consulted with trained clinicians recalled consultation discussion about a health behaviour (724/795 (91%) v 531/966 (55%), odds ratio 12.44 (5.85 to 26.46)) and intended to change (599/831 (72%) v 491/996 (49%), odds ratio 2.88 (2.05 to 4.05)). More intervention practice patients reported making an attempt to change (328 (39%) v 317 (32%), odds ratio 1.40 (1.15 to 1.70)), a sustained behaviour change at three months (288 (35%) v 280 (28%), odds ratio 1.36 (1.11 to 1.65)), and reported slightly greater improvements in healthy eating at three and 12 months, plus improved activity at 12 months. Training cost £1597 per practice. Training primary care clinicians in behaviour change counselling using a brief blended learning programme did not increase patients reported beneficial behaviour change at three months or improve biometric and a biochemical measure at 12 months, but it did increase patients' recollection of discussing behaviour change with their clinicians, intentions to change, attempts to change, and perceptions of having made a lasting change at three months. Enduring behaviour change and improvements in biometric measures are unlikely after a single routine consultation with a clinician trained in behaviour change counselling without additional intervention. ISRCTN 22495456.

Mode of Action (MOA) and Dose-Response Approaches for Nuclear Receptors

EPA Science Inventory

Abstract: The presence of sub-threshold doses for non-cancer and (in appropriate cases) cancer has been the dominant paradigm for the practice of risk assessment, but the application of dose-response modeling approaches that include a threshold have been questioned in a 2009 NRC ...

Paternal Autistic Traits Are Predictive of Infants Visual Attention

ERIC Educational Resources Information Center

Ronconi, Luca; Facoetti, Andrea; Bulf, Hermann; Franchin, Laura; Bettoni, Roberta; Valenza, Eloisa

2014-01-01

Since subthreshold autistic social impairments aggregate in family members, and since attentional dysfunctions appear to be one of the earliest cognitive markers of children with autism, we investigated in the general population the relationship between infants' attentional functioning and the autistic traits measured in their parents.…

Written Expression Performance in Adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD)

ERIC Educational Resources Information Center

DeBono, Tony; Hosseini, Armita; Cairo, Cassandra; Ghelani, Karen; Tannock, Rosemary; Toplak, Maggie E.

2012-01-01

We examined written expression performance in a sample of adolescents with ADHD and subthreshold ADHD using two different strategies: examining performance on standardized measures of written expression and using other indicators of written expression developed in this study. We examined associations between standardized measures of written…

DSM-IV-defined anorexia nervosa versus subthreshold anorexia nervosa (EDNOS-AN).

PubMed

Le Grange, Daniel; Crosby, Ross D; Engel, Scott G; Cao, Li; Ndungu, Alfred; Crow, Scott J; Peterson, Carol B; Mitchell, James E; Wonderlich, Stephen A

2013-01-01

Eating disorder not otherwise specified (EDNOS) is the most prevalent eating disorder, yet its heterogeneity begs less reliance on this broad diagnostic category. The purpose of this study was to compare women with anorexia nervosa (AN) and EDNOS, AN type (EDNOS-AN) from a multisite study on eating-related and general psychopathology measures. One hundred eighteen participants (n = 59 with DSM-IV AN, n = 59 with EDNOS-AN) completed structured interviews, questionnaires and a physical examination at baseline. In addition, participants carried a handheld palm pilot computer for 2 weeks to provide ecological momentary assessment (EMA) information about mood and eating disorder behaviours. No significant differences between AN and EDNOS-AN were found on the self-report and interview measures, or on the EMA mood assessments. The only differences to emerge were that participants with AN reported higher rates of binge eating and purging on EMA compared with those with EDNOS-AN, whereas EDNOS-AN reported higher rates of checking thighs and joints on EMA compared with those with AN. For the physiological parameters, AN presented with lower white blood cell counts compared with EDNOS-AN. Findings highlight the clinical significance of EDNOS-AN and support a closer look at the definition of AN as proposed by the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. Copyright © 2012 John Wiley & Sons, Ltd and Eating Disorders Association.

Surface stoichiometry modification and improved DC/RF characteristics by plasma treated and annealed AlGaN/GaN HEMTs

NASA Astrophysics Data System (ADS)

Upadhyay, Bhanu B.; Takhar, Kuldeep; Jha, Jaya; Ganguly, Swaroop; Saha, Dipankar

2018-03-01

We demonstrate that N2 and O2 plasma treatment followed by rapid thermal annealing leads to surface stoichiometry modification in a AlGaN/GaN high electron mobility transistor. Both the source/drain access and gate regions respond positively improving the transistor characteristics albeit to different extents. Characterizations indicate that the surface show the characteristics of that of a higher band-gap material like AlxOy and GaxOy along with N-vacancy in the sub-surface region. The N-vacancy leads to an increased two-dimensional electron gas density. The formation of oxides lead to a reduced gate leakage current and surface passivation. The DC characteristics show increased transconductance, saturation drain current, ON/OFF current ratio, sub-threshold swing and lower ON resistance by a factor of 2.9, 2.0, 103.3 , 2.3, and 2.1, respectively. The RF characteristics show an increase in unity current gain frequency by a factor of 1.7 for a 500 nm channel length device.

Improving performance of armchair graphene nanoribbon field effect transistors via boron nitride doping

NASA Astrophysics Data System (ADS)

Goharrizi, A. Yazdanpanah; Sanaeepur, M.; Sharifi, M. J.

2015-09-01

Device performance of 10 nm length armchair graphene nanoribbon field effect transistors with 1.5 nm and 4 nm width (13 and 33 atoms in width respectively) are compared in terms of Ion /Ioff , trans-conductance, and sub-threshold swing. While narrow devices suffer from edge roughness wider devices are subject to more substrate surface roughness and reduced bandgap. Boron Nitride doping is employed to compensate reduced bandgap in wider devices. Simultaneous effects of edge and substrate surface roughness are considered. Results show that in the presence of both the edge and substrate surface roughness the 4 nm wide device with boron nitride doping shows improved performance with respect to the 1.5 nm one (both of which incorporate the same bandgap AGNR as channel material). Electronic simulations are performed via NEGF method along with tight-binding Hamiltonian. Edge and surface roughness are created by means of one and two dimensional auto correlation functions respectively. Electronic characteristics are averaged over a large number of devices due to statistic nature of both the edge and surface roughness.

Effect of graded InGaN drain region and 'In' fraction in InGaN channel on performances of InGaN tunnel field-effect transistor

NASA Astrophysics Data System (ADS)

Duan, Xiaoling; Zhang, Jincheng; Wang, Shulong; Quan, Rudai; Hao, Yue

2017-12-01

An InGaN-based graded drain region tunnel field-effect transistor (GD-TFET) is proposed to suppress the ambipolar behavior. The simulation results with the trade-off between on-state current (Ion) and ambipolar current (Iambipolar) show decreased Iambipolar (1.9 × 10-14 A/μm) in comparison with that of conventional TFETs (2.0 × 10-8 A/μm). Furthermore, GD-TFET with high 'In' fraction InxGa1-xN source-side channel (SC- GD-TFET) is explored and exhibits 5.3 times Ion improvement and 60% average subthreshold swing (SSavg) reduction in comparison with GD-TFET by adjusting 'In' fraction in the InxGa1-xN source-side channel. The improvement is attributed to the confinement of BTBT in the source-side channel by the heterojunction. And then, the optimum value for source-side channel length (Lsc) is researched by DC performances results, which shows it falls into the range between Lsc = 10 nm and 20 nm.

Improved detection of electrical activity with a voltage probe based on a voltage-sensing phosphatase.

PubMed

Tsutsui, Hidekazu; Jinno, Yuka; Tomita, Akiko; Niino, Yusuke; Yamada, Yoshiyuki; Mikoshiba, Katsuhiko; Miyawaki, Atsushi; Okamura, Yasushi

2013-09-15

  One of the most awaited techniques in modern physiology is the sensitive detection of spatiotemporal electrical activity in a complex network of excitable cells. The use of genetically encoded voltage probes has been expected to enable such analysis. However, in spite of recent progress, existing probes still suffer from low signal amplitude and/or kinetics too slow to detect fast electrical activity. Here, we have developed an improved voltage probe named Mermaid2, which is based on the voltage-sensor domain of the voltage-sensing phosphatase from Ciona intestinalis and Förster energy transfer between a pair of fluorescent proteins. In mammalian cells, Mermaid2 permits ratiometric readouts of fractional changes of more than 50% over a physiologically relevant voltage range with fast kinetics, and it was used to follow a train of action potentials at frequencies of up to 150 Hz. Mermaid2 was also able to detect single action potentials and subthreshold voltage responses in hippocampal neurons in vitro, in addition to cortical electrical activity evoked by sound stimuli in single trials in living mice.

Thin-film morphology of inkjet-printed single-droplet organic transistors using polarized Raman spectroscopy: effect of blending TIPS-pentacene with insulating polymer.

PubMed

James, David T; Kjellander, B K Charlotte; Smaal, Wiljan T T; Gelinck, Gerwin H; Combe, Craig; McCulloch, Iain; Wilson, Richard; Burroughes, Jeremy H; Bradley, Donal D C; Kim, Ji-Seon

2011-12-27

We report thin-film morphology studies of inkjet-printed single-droplet organic thin-film transistors (OTFTs) using angle-dependent polarized Raman spectroscopy. We show this to be an effective technique to determine the degree of molecular order as well as to spatially resolve the orientation of the conjugated backbones of the 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-Pentacene) molecules. The addition of an insulating polymer, polystyrene (PS), does not disrupt the π-π stacking of the TIPS-Pentacene molecules. Blending in fact improves the uniformity of the molecular morphology and the active layer coverage within the device and reduces the variation in molecular orientation between polycrystalline domains. For OTFT performance, blending enhances the saturation mobility from 0.22 ± 0.05 cm(2)/(V·s) (TIPS-Pentacene) to 0.72 ± 0.17 cm(2)/(V·s) (TIPS-Pentacene:PS) in addition to improving the quality of the interface between TIPS-Pentacene and the gate dielectric in the channel, resulting in threshold voltages of ∼0 V and steep subthreshold slopes.

Partnership work between Public Health and Health Psychology: introduction to a novel training programme

PubMed Central

2010-01-01

Background Public health services implement individual, community and population level interventions to change health behaviours, improve healthy life expectancy and reduce health inequalities. Understanding and changing health behaviour is complex. Integrating behaviour change theory and evidence into interventions has the potential to improve services. Methods Health Psychologists apply evidence and theories aimed at understanding and changing health behaviour. A Scottish programme is piloting the training of Health Psychologists within NHS contexts to address prominent public health challenges. Results This article outlines the details of this novel programme. Two projects are examined to illustrate the potential of partnership working between public health and health psychology. Conclusion In order to develop and improve behaviour change interventions and services, public health planners may want to consider developing and using the knowledge and skills of Health Psychologists. Supporting such training within public health contexts is a promising avenue to build critical NHS internal mass to tackle the major public health challenges ahead. PMID:21070643

Measurement of Restricted and Repetitive Behaviour in Children with Autism Spectrum Disorder: Selecting a Questionnaire or Interview

ERIC Educational Resources Information Center

Honey, Emma; Rodgers, Jacqui; McConachie, Helen

2012-01-01

Assessment of children's restricted and repetitive behaviours offers potential opportunities to improve early diagnosis of autism spectrum disorder (ASD) and timely access to interventions and support. To facilitate this requires understanding of the phenomenology of repetitive behaviours in ASD, including differentiating behaviours seen in ASD…

A randomised group comparison controlled trial of 'preschoolers with autism': a parent education and skills training intervention for young children with autistic disorder.

PubMed

Tonge, Bruce; Brereton, Avril; Kiomall, Melissa; Mackinnon, Andrew; Rinehart, Nicole J

2014-02-01

To determine the effect of parent education on adaptive behaviour, autism symptoms and cognitive/language skills of young children with autistic disorder. A randomised group comparison design involving a parent education and counselling intervention and a parent education and behaviour management intervention to control for parent skills training and a control sample. Two rural and two metropolitan regions were randomly allocated to intervention groups (n = 70) or control (n = 35). Parents from autism assessment services in the intervention regions were randomly allocated to parent education and behaviour management (n = 35) or parent education and counselling (n = 35). Parent education and behaviour management resulted in significant improvement in adaptive behaviour and autism symptoms at 6 months follow-up for children with greater delays in adaptive behaviour. Parent education and behaviour management was superior to parent education and counselling. We conclude that a 20-week parent education programme including skills training for parents of young children with autistic disorder provides significant improvements in child adaptive behaviour and symptoms of autism for low-functioning children.

An extended version of the theory of planned behaviour: the role of self-efficacy and past behaviour in predicting the physical activity of Chinese adolescents.

PubMed

Wang, Lijuan; Zhang, Ying

2016-01-01

This study aimed to use an extended theory of planned behaviour (TPB), which incorporated additional self-efficacy and past behaviour, to predict the intention to engage in moderate-to-vigorous physical activity (MVPA) and the MVPA level of Chinese adolescents. Questionnaires that focused on MVPA, attitude, subjective norm, perceived behavioural control (PBC), self-efficacy and past behaviour related to the MVPA engagement were administered to a sample of 488 young people. Multiple regression analyses provided moderate support for TPB. Three TPB constructs predicted 28.7% of the variance in intentions to engage in MVPA, and that PBC, but not intention, explained 3.4% of the variance in MVPA. Self-efficacy significantly affected intention and behaviour over and above the influence of TPB. Past behaviour had a small but significant improvement in the prediction of intention, but no improvement in the prediction of MVPA. Based on the results, interventions should target adolescent self-efficacy and PBC in physical activity participation.

Vagus nerve stimulation in 15 children with therapy resistant epilepsy; its impact on cognition, quality of life, behaviour and mood.

PubMed

Hallböök, Tove; Lundgren, Johan; Stjernqvist, Karin; Blennow, Gösta; Strömblad, Lars-Göran; Rosén, Ingmar

2005-10-01

Vagus nerve stimulation (VNS) is a neurophysiologic treatment for patients with refractory epilepsy. There is growing evidence of additional quality of life (QOL) benefits of VNS. We report the effects of VNS on seizure frequency and severity and how these changes are related to cognitive abilities, QOL, behaviour and mood in 15 children with medically refractory and for surgery not eligible epilepsy. Initially, and after 3 and 9 months of VNS-treatment, 15 children were investigated with Bayley Scales of Infant Development (BSID), Wechsler Preschool and Primary Scale of Intelligence (WPPSI-R), Wechlser Intelligence Scales for Children (WISC-III) depending on the child's level of functioning, a Visual Analogue Scale for validating QOL, Child Behaviour Checklist (CBCL) for quantifying behaviour problems, Dodrill Mood Analogue Scale and Birleson Depression Self-Rating Scale, and the National Hospital Seizure Severity Scale (NHS3). A diary of seizure frequency was collected. Six of 15 children showed a 50% or more reduction in seizure frequency; one of these became seizure-free. Two children had a 25-50% seizure reduction. Two children showed increased seizure frequency. In 13 of 15 children there was an improvement in NHS3. The parents reported shorter duration of seizure and recovery phase. There were no changes in cognitive functioning. Twelve children showed an improvement in QOL. Eleven of these also improved in seizure severity and mood and five also in depressive parameters. This study has shown a good anti-seizure effect of VNS, an improvement in seizure severity and in QOL and a tendency to improvement over time regarding behaviour, mood and depressive parameters. The improvement in seizure severity, QOL, behaviour, mood and depressive parameters was not related to the anti-seizure effect.

How a smiley protects health: A pilot intervention to improve hand hygiene in hospitals by activating injunctive norms through emoticons

PubMed Central

Tsivrikos, Dimitrios; Dollinger, Daniel; Lermer, Eva

2018-01-01

Hand hygiene practice in hospitals is unfortunately still widely insufficient, even though it is known that transmitting pathogens via hands is the leading cause of healthcare-associated infections. Previous research has shown that improving knowledge, providing feedback on past behaviour and targeting social norms are promising approaches to improve hand hygiene practices. The present field experiment was designed to direct people on when to perform hand hygiene and prevent forgetfulness. This intervention is the first to examine the effect of inducing injunctive social norms via an emoticon-based feedback system on hand hygiene behaviour. Electronic monitoring and feedback devices were installed in hospital patient rooms on top of hand-rub dispensers, next to the doorway, for a period of 17 weeks. In the emoticon condition, screens at the devices activated whenever a person entered or exited the room. Before using the alcohol-based hand-rub dispenser, a frowny face was displayed, indicating that hand hygiene should be performed. If the dispenser was subsequently used, this picture changed to a smiley face to positively reinforce the correct behaviour. Hand hygiene behaviour in the emoticon rooms significantly outperformed the behaviour in three other tested conditions. The strong effect in this field experiment indicates that activating injunctive norms may be a promising approach to improve hand hygiene behaviour. Theoretical and practical implications of these findings are discussed. PMID:29782516

A Self-Aligned a-IGZO Thin-Film Transistor Using a New Two-Photo-Mask Process with a Continuous Etching Scheme.

PubMed

Fan, Ching-Lin; Shang, Ming-Chi; Li, Bo-Jyun; Lin, Yu-Zuo; Wang, Shea-Jue; Lee, Win-Der

2014-08-11

Minimizing the parasitic capacitance and the number of photo-masks can improve operational speed and reduce fabrication costs. Therefore, in this study, a new two-photo-mask process is proposed that exhibits a self-aligned structure without an etching-stop layer. Combining the backside-ultraviolet (BUV) exposure and backside-lift-off (BLO) schemes can not only prevent the damage when etching the source/drain (S/D) electrodes but also reduce the number of photo-masks required during fabrication and minimize the parasitic capacitance with the decreasing of gate overlap length at same time. Compared with traditional fabrication processes, the proposed process yields that thin-film transistors (TFTs) exhibit comparable field-effect mobility (9.5 cm²/V·s), threshold voltage (3.39 V), and subthreshold swing (0.3 V/decade). The delay time of an inverter fabricated using the proposed process was considerably decreased.

A Self-Aligned a-IGZO Thin-Film Transistor Using a New Two-Photo-Mask Process with a Continuous Etching Scheme

PubMed Central

Fan, Ching-Lin; Shang, Ming-Chi; Li, Bo-Jyun; Lin, Yu-Zuo; Wang, Shea-Jue; Lee, Win-Der

2014-01-01

Minimizing the parasitic capacitance and the number of photo-masks can improve operational speed and reduce fabrication costs. Therefore, in this study, a new two-photo-mask process is proposed that exhibits a self-aligned structure without an etching-stop layer. Combining the backside-ultraviolet (BUV) exposure and backside-lift-off (BLO) schemes can not only prevent the damage when etching the source/drain (S/D) electrodes but also reduce the number of photo-masks required during fabrication and minimize the parasitic capacitance with the decreasing of gate overlap length at same time. Compared with traditional fabrication processes, the proposed process yields that thin-film transistors (TFTs) exhibit comparable field-effect mobility (9.5 cm2/V·s), threshold voltage (3.39 V), and subthreshold swing (0.3 V/decade). The delay time of an inverter fabricated using the proposed process was considerably decreased. PMID:28788159

The effect of thermal annealing on pentacene thin film transistor with micro contact printing.

PubMed

Shin, Hong-Sik; Yun, Ho-Jin; Baek, Kyu-Ha; Ham, Yong-Hyun; Park, Kun-Sik; Kim, Dong-Pyo; Lee, Ga-Won; Lee, Hi-Deok; Lee, Kijun; Do, Lee-Mi

2012-07-01

We used micro contact printing (micro-CP) to fabricate inverted coplanar pentacene thin film transistors (TFTs) with 1-microm channels. The patterning of micro-scale source/drain electrodes without etch process was successfully achieved using Polydimethylsiloxane (PDMS) elastomer stamp. We used the Ag nano particle ink as an electrode material, and the sheet resistance and surface roughness of the Ag electrodes were effectively reduced with the 2-step thermal annealing on a hotplate, which improved the mobility, the on-off ratio, and the subthreshold slope (SS) of the pentacene TFTs. In addition, the device annealing on a hotplate in a N2 atmosphere for 30 sec can enhance the off-current and the mobility properties of OTFTs without damaging the pentacene thin films and increase the adhesion between pentacene and dielectric layer (SiO2), which was investigated with the pentacene films phase change of the XRD spectrum after device annealing.

Reduction of hysteresis in solution-processed InGaZnO thin-film transistors through uni-directional pre-annealing

NASA Astrophysics Data System (ADS)

Kim, Young-Rae; Kwon, Jin-Hyuk; Vincent, Premkumar; Kim, Do-Kyung; Jeong, Hyeon-Seok; Hahn, Joonku; Bae, Jin-Hyuk; Park, Jaehoon

2018-01-01

The hysteresis of the solution-processed oxide thin-film transistors (TFTs) is fatal issue to interrupt stable operation. So, we came up with uni-directional pre-annealing to solve the problem. There are inevitable defects when solution-processed oxide TFTs are fabricated, due to the porosities by the solvent volatilization. Also oxygen vacancies needed for carrier generation in metal oxide semiconductor can be trap states inducing charge carrier trapping. Uni-directional pre-annealing improved the hysteresis, preventing randomly solvent evaporation and decreased the defects of the film. We can result in advanced stability of the solution-processed oxide TFTs, at the same time showing that the field effect mobility was enhanced from 3.35 cm2/Vs to 4.78 cm2/Vs simultaneously, and exhibiting better subthreshold swing from 0.89 V/dec to 0.23 V/dec.

Effects of Electron Beam Irradiation and Thiol Molecule Treatment on the Properties of MoS2 Field Effect Transistors

NASA Astrophysics Data System (ADS)

Choi, Barbara Yuri; Cho, Kyungjune; Pak, Jinsu; Kim, Tae-Young; Kim, Jae-Keun; Shin, Jiwon; Seo, Junseok; Chung, Seungjun; Lee, Takhee

2018-05-01

We investigated the effects of the structural defects intentionally created by electron-beam irradiation with an energy of 30 keV on the electrical properties of monolayer MoS2 field effect transistors (FETs). We observed that the created defects by electron beam irradiation on the MoS2 surface working as trap sites deteriorated the carrier mobility and carrier concentration with increasing the subthreshold swing value and shifting the threshold voltage in MoS2 FETs. The electrical properties of electron-beam irradiated MoS2 FETs were slightly improved by treating the devices with thiol-terminated molecules which presumably passivated the structural defects of MoS2. The results of this study may enhance the understanding of the electrical properties of MoS2 FETs in terms of creating and passivating defect sites.

Reliability and Utility of the Behaviour Support Plan Quality Evaluation Tool (BSP-QEII) for Auditing and Quality Development in Services for Adults with Intellectual Disability and Challenging Behaviour

ERIC Educational Resources Information Center

McVilly, K.; Webber, L.; Paris, M.; Sharp, G.

2013-01-01

Background: Having an objective means of evaluating the quality of behaviour support plans (BSPs) could assist service providers and statutory authorities to monitor and improve the quality of support provided to people with intellectual disability (ID) who exhibit challenging behaviour. The Behaviour Support Plan Quality Evaluation Guide II…

Maternal feeding behaviour and young children's dietary quality: A cross-sectional study of socially disadvantaged mothers of two-year old children using the Theory of Planned Behaviour

PubMed Central

2011-01-01

Background Having breakfast, eating food 'cooked from scratch' and eating together as a family have health and psychosocial benefits for young children. This study investigates how these parentally determined behaviours relate to children's dietary quality and uses a psychological model, the Theory of Planned Behaviour (TPB), to investigate socio-cognitive predictors of these behaviours in socially disadvantaged mothers of young children in Scotland. Method Three hundred mothers of children aged 2 years (from 372 invited to participate, 81% response rate), recruited via General Practitioners, took part in home-based semi-structured interviews in a cross-sectional survey of maternal psychological factors related to their children's dietary quality. Regression analyses examined statistical predictors of maternal intentions and feeding behaviours. Results Mothers of children with poorer quality diets were less likely than others to provide breakfast every day, cook from 'scratch' and provide 'proper sit-down meals'. TPB socio-cognitive factors (intentions, perceived behavioural control) significantly predicted these three behaviours, and attitudes, norms, and perceived behavioural control significantly predicted mothers' intentions, with medium to large effect sizes. Conclusions Interventions to improve young children's dietary health could benefit from a focus on modifying maternal motivations and attitudes in attempts to improve feeding behaviours. PMID:21699714

Maternal feeding behaviour and young children's dietary quality: a cross-sectional study of socially disadvantaged mothers of two-year old children using the Theory of Planned Behaviour.

PubMed

Swanson, Vivien; Power, Kevin G; Crombie, Iain K; Irvine, Linda; Kiezebrink, Kirsty; Wrieden, Wendy; Slane, Peter W

2011-06-23

Having breakfast, eating food 'cooked from scratch' and eating together as a family have health and psychosocial benefits for young children. This study investigates how these parentally determined behaviours relate to children's dietary quality and uses a psychological model, the Theory of Planned Behaviour (TPB), to investigate socio-cognitive predictors of these behaviours in socially disadvantaged mothers of young children in Scotland. Three hundred mothers of children aged 2 years (from 372 invited to participate, 81% response rate), recruited via General Practitioners, took part in home-based semi-structured interviews in a cross-sectional survey of maternal psychological factors related to their children's dietary quality. Regression analyses examined statistical predictors of maternal intentions and feeding behaviours. Mothers of children with poorer quality diets were less likely than others to provide breakfast every day, cook from 'scratch' and provide 'proper sit-down meals'. TPB socio-cognitive factors (intentions, perceived behavioural control) significantly predicted these three behaviours, and attitudes, norms, and perceived behavioural control significantly predicted mothers' intentions, with medium to large effect sizes. Interventions to improve young children's dietary health could benefit from a focus on modifying maternal motivations and attitudes in attempts to improve feeding behaviours.

Teaching renewable energy using online PBL in investigating its effect on behaviour towards energy conservation among Malaysian students: ANOVA repeated measures approach

NASA Astrophysics Data System (ADS)

Nordin, Norfarah; Samsudin, Mohd Ali; Hadi Harun, Abdul

2017-01-01

This research aimed to investigate whether online problem based learning (PBL) approach to teach renewable energy topic improves students’ behaviour towards energy conservation. A renewable energy online problem based learning (REePBaL) instruction package was developed based on the theory of constructivism and adaptation of the online learning model. This study employed a single group quasi-experimental design to ascertain the changed in students’ behaviour towards energy conservation after underwent the intervention. The study involved 48 secondary school students in a Malaysian public school. ANOVA Repeated Measure technique was employed in order to compare scores of students’ behaviour towards energy conservation before and after the intervention. Based on the finding, students’ behaviour towards energy conservation improved after the intervention.

Changes in illness perceptions mediated the effect of cognitive behavioural therapy in severe functional somatic syndromes.

PubMed

Christensen, Sara Sletten; Frostholm, Lisbeth; Ørnbøl, Eva; Schröder, Andreas

2015-04-01

Although there is substantial evidence that cognitive behavioural therapy alleviates symptoms in functional somatic syndromes, the mechanisms of change are less investigated. This study examined whether changes in illness perceptions mediated the effect of cognitive behavioural therapy. We analysed additional data from a randomised controlled trial comparing completers of cognitive behavioural group therapy (46 patients) to an enhanced usual care group (66 patients). Proposed mediators (illness perceptions) and primary (physical health) and secondary (somatic symptoms and illness worry) outcomes were assessed by means of questionnaires at referral, baseline, end of treatment, and 10 and 16 months after randomisation. Multiple mediation analysis determined whether (1) changes in specific illness perceptions during treatment mediated the effect of cognitive behavioural therapy (primary analysis), and (2) whether changes in illness perceptions during the whole trial period were associated with improved outcome (secondary analysis). Improvements in illness perceptions during treatment partially mediated the effect of cognitive behavioural therapy on physical health one year after treatment (sum of indirect effects 1.556, BCa 95% CI (0.006; 3.620)). Improving perceived control was particularly important. Changes in illness perceptions from baseline to 16 months after randomisation were associated with clinically meaningful improvements in physical health, somatic symptoms and illness worry during the same period. Our results suggest that changing patients' illness perceptions is an important process in cognitive behavioural therapy for functional somatic syndromes. Challenging patients' own understanding of their illness may hence be a key element of successful treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

Interventions that involve parents to improve children's weight-related nutrition intake and activity patterns - what nutrition and activity targets and behaviour change techniques are associated with intervention effectiveness?

PubMed

Golley, R K; Hendrie, G A; Slater, A; Corsini, N

2011-02-01

Parent involvement is an important component of obesity prevention interventions. However, the best way to support parents remains unclear. This review identifies interventions targeting parents to improve children's weight status, dietary and/or activity patterns, examines whether intervention content and behaviour change techniques employed are associated with effectiveness. Seventeen studies, in English, 1998-2008, were included. Studies were evaluated by two reviewers for study quality, nutrition/activity content and behaviour change techniques using a validated quality assessment tool and behaviour change technique taxonomy. Study findings favoured intervention effectiveness in 11 of 17 studies. Interventions that were considered effective had similar features: better study quality, parents responsible for participation and implementation, greater parental involvement and inclusion of prompt barrier identification, restructure the home environment, prompt self-monitoring, prompt specific goal setting behaviour change techniques. Energy intake/density and food choices were more likely to be targeted in effective interventions. The number of lifestyle behaviours targeted did not appear to be associated with effectiveness. Intervention effectiveness was favoured when behaviour change techniques spanned the spectrum of behaviour change process. The review provides guidance for researchers to make informed decisions on how best to utilize resources in interventions to support and engage parents, and highlights a need for improvement in intervention content reporting practices. © 2010 The Authors. obesity reviews © 2010 International Association for the Study of Obesity.

Correcting the eating disorder in anorexia nervosa.

PubMed

Wilson, A J; Touyz, S W; O'Connor, M; Beumont, P J

1985-01-01

The aim of the present study was to assess whether direct informational feedback using videotape recordings would improve abnormal eating behaviour in patients with anorexia nervosa. Eight inpatients participated in the study. A statistically significant improvement was noted in the occurrence of obsessional eating behaviour and in table manners. However, there was no change in the speed of eating, disposal of food or behaviours which reduce caloric intake. The implications of these findings for the treatment and prognosis of anorexia nervosa are discussed.

COMBINATION THERAPY OF INTRAVITREAL RANIBIZUMAB AND SUBTHRESHOLD MICROPULSE PHOTOCOAGULATION FOR MACULAR EDEMA SECONDARY TO BRANCH RETINAL VEIN OCCLUSION: 6-MONTH RESULT.

PubMed

Terashima, Hiroko; Hasebe, Hiruma; Okamoto, Fumiki; Matsuoka, Naoki; Sato, Yayoi; Fukuchi, Takeo

2018-04-23

To determine the efficacy of the combination therapy of intravitreal ranibizumab (IVR) and 577-nm yellow laser subthreshold micropulse laser photocoagulation (SMLP) for macular edema secondary to branch retinal vein occlusion cystoid macular edema. Retrospective, consecutive, case-control study. Forty-six eyes of 46 patients with treatment-naive branch retinal vein occlusion cystoid macular edema were enrolled. The IVR + SMLP group consisted of 22 patients who had undergone both SMLP and IVR. Intravitreal ranibizumab group consisted of 24 patients who had undergone IVR monotherapy. Intravitreal ranibizumab therapy was one initial injection and on a pro re nata in both groups, and SMLP was performed at 1 month after IVR in the IVR + SMLP group. Preoperatively and monthly, best-corrected visual acuity and central retinal thickness were evaluated using swept source optical coherence tomography. Best-corrected visual acuity and central retinal thickness significantly improved at 6 months in IVR + SMLP and IVR groups. Best-corrected visual acuity and central retinal thickness were not significantly different between the two groups at any time points. The number of IVR injections during initial 6 months in IVR group (2.3 ± 0.9) was significantly greater (P = 0.034) than that in IVR + SMLP group (1.9 ± 0.8). The combination therapy of IVR and SMLP can treat branch retinal vein occlusion cystoid macular edema effectively, by decreasing the frequency of IVR injections while maintaining good visual acuity.This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.

Prevention of anxiety and depression in Chinese: a randomized clinical trial testing the effectiveness of a stepped care program in primary care.

PubMed

Zhang, De Xing; Lewis, Glyn; Araya, Ricardo; Tang, Wai Kwong; Mak, Winnie Wing Sze; Cheung, Fanny Mui Ching; Mercer, Stewart William; Griffiths, Sian Meryl; Woo, Jean; Lee, Diana Tze Fan; Kung, Kenny; Lam, Augustine Tsan; Yip, Benjamin Hon Kei; Wong, Samuel Yeung Shan

2014-12-01

Despite empirical evidence demonstrating the effectiveness of collaborative stepped care program (SCP) in Western countries, such programs have not been evaluated in the east, which has a different services system structure and cultural nuances in seeking help for mental illness. Furthermore, only a few studies have used SCP for depression and anxiety prevention. We conducted a trial to test its effectiveness in preventing major depressive disorder and generalized anxiety disorder among primary care patients with subthreshold depression and/or anxiety in Hong Kong. Subthreshold depression and/or anxiety patients were randomized into the SCP group (n=121) or care as usual (CAU) group (n=119). The SCP included watchful waiting, telephone counseling, problem solving therapy, and family doctor treatment within one year. The primary outcome was the onset of major depressive disorder or generalized anxiety disorder in 15 months. The secondary outcomes were depressive and anxiety symptoms, quality of life and time absent from work due to any illness. Survival analysis showed no differences between the SCP and CAU groups (the cumulative probability of onset at 15 month was 23.1% in the SCP group and 20.5% in the CAU group; Hazard Ratio=1.62; 95% Confidence Interval: 0.82-3.18; p=0.16). No significant differences were found in secondary outcomes. Sample size might not have been large enough. SCP did not show beneficial effect on depression/anxiety prevention compared with CAU in Hong Kong primary care. As a large majority of patients improved overtime without any intervention, we are not able to exclude the possibility that the intervention might be effective. Future studies would need to have a larger sample size and conduct on patients with more severe symptoms or perform a second screening. Copyright © 2014 Elsevier B.V. All rights reserved.

The DSM-5 nonsuicidal self-injury disorder among incoming college students: Prevalence and associations with 12-month mental disorders and suicidal thoughts and behaviors.

PubMed

Kiekens, Glenn; Hasking, Penelope; Claes, Laurence; Mortier, Philippe; Auerbach, Randy P; Boyes, Mark; Cuijpers, Pim; Demyttenaere, Koen; Green, Jennifer G; Kessler, Ronald C; Nock, Matthew K; Bruffaerts, Ronny

2018-04-26

Approximately one in five college students report a history of nonsuicidal self-injury. However, it is unclear how many students meet criteria for the recently proposed DSM-5 nonsuicidal self-injury disorder (NSSI-D). In this study, we used full NSSI-D criteria to identify those students most in need of clinical care. Using data from the Leuven College Surveys (n = 4,565), we examined the 12-month prevalence of DSM-5 NSSI-D in a large and representative sample of incoming college students. We also explored the optimal frequency threshold as a function of interference in functioning due to NSSI, and examined comorbidity patterns with other 12-month mental disorders (i.e., major depressive disorder, broad mania, generalized anxiety disorder, panic disorder, and alcohol dependence) and suicidal thoughts and behaviors (STB). Twelve-month NSSI-D prevalence was 0.8% and more common among females (1.1%) than males (0.4%). The proposed 5+ diagnostic threshold was confirmed as yielding highest discrimination between threshold and subthreshold cases in terms of distress or disability due to NSSI. A dose-response relationship was observed for NSSI recency-severity (i.e., 12-month NSSI-D, subthreshold 12-month NSSI-D, past NSSI, no history of NSSI) with number of 12-month mental disorders and STB. NSSI-D occurred without comorbid disorders for one in five individuals, and remained associated with severe role impairment when controlling for the number of comorbid disorders. These findings offer preliminary evidence that DSM-5 NSSI-D is uncommon among incoming college students, but may help to improve the deployment of targeted resource allocation to those most in need of services. More work examining the validity of NSSI-D is required. © 2018 Wiley Periodicals, Inc.

Test Review: "Social Responsiveness Scale" by J. N. Constantino and C. P. Gruber

ERIC Educational Resources Information Center

Booker, Kimberly Wilson; Starling, LaRonda

2011-01-01

Published by Western Psychological Services, the "Social Responsiveness Scale" (SRS; Constantino & Gruber, 2005) was designed to assess abilities and deficits in social reciprocity. In particular, it was designed to assess subthreshold levels and severity of social impairment, a key marker of pervasive developmental disorders. The SRS may be…

Subthreshold Depressive Disorder in Adolescents: Predictors of Escalation to Full-Syndrome

ERIC Educational Resources Information Center

Klein, Daniel N.; Shankman, Stewart A.; Lewinsohn, Peter M.; Seeley, John R.

2009-01-01

The risk for the onset of full-syndrome depressive disorders from the subtreshold depressive disorder in adolescents is found to be at 67 percent. The variables that predict the progression to the full onset are: severity of depressive symptoms, medical conditions/ symptoms, history of suicidal ideation, history of anxiety disorder, and familial…

Efficacy of an Internet-Based Intervention Targeted to Adolescents with Subthreshold Depression

ERIC Educational Resources Information Center

Makarushka, Marta Maria

2011-01-01

Depression during adolescence is highly prevalent with as many as 20% experiencing a major depressive episode by the age of 18. Adolescent depression causes significant impairment across life areas including school functioning, such as poor academic performance and decreased academic achievement. Despite the existence of many evidence-based…

Factors Associated with the Severity of Gambling Problems in a Community Gambling Treatment Agency

ERIC Educational Resources Information Center

Namrata, Raylu; Oei, Tian P. S.

2009-01-01

Factors (demographics, gambling behaviors and comorbid problems) that may be related to the severity of gambling problems were investigated among 440 problem gamblers seeking treatment in an Australian outpatient treatment agency. The participants were divided into sub-threshold pathological gamblers (SPGs; N = 104) and pathological gamblers (PGs;…

Availability of Semantic Knowledge in Familiar-Only Experiences for Names

ERIC Educational Resources Information Center

Bowles, Ben; Köhler, Stefan

2014-01-01

Situations in which the name of a person is perceived as familiar but does not trigger recall of pertinent semantic knowledge are common in daily life. In current connectionist models of person recognition, such "familiar-only" experiences reflect supra-threshold activation at person-identity nodes but subthreshold activation at nodes…

Comprehensive Comparison of Self-Administered Questionnaires for Measuring Quantitative Autistic Traits in Adults

ERIC Educational Resources Information Center

Nishiyama, Takeshi; Suzuki, Masako; Adachi, Katsunori; Sumi, Satoshi; Okada, Kensuke; Kishino, Hirohisa; Sakai, Saeko; Kamio, Yoko; Kojima, Masayo; Suzuki, Sadao; Kanne, Stephen M.

2014-01-01

We comprehensively compared all available questionnaires for measuring quantitative autistic traits (QATs) in terms of reliability and construct validity in 3,147 non-clinical and 60 clinical subjects with normal intelligence. We examined four full-length forms, the Subthreshold Autism Trait Questionnaire (SATQ), the Broader Autism Phenotype…

Caffeine, Adenosine Receptors and Estrogen in Toxin Models of Parkinson’s Disease

DTIC Science & Technology

2007-10-01

KW-6002 (3 mg/kg, ip; in the presence of a sub-threshold dose of the dopamine D2 antagonist haloperidol ) induced ipsilateral turning, and amphetamine... haloperidol ) induced ipsilateral turning, and amphetamine (2.5 mg/kg i.p. on its own) induced contralateral turning relative to that in the control

Backward Masking: Evidence of Reduced Subcortical Amygdala Engagement in Autism

ERIC Educational Resources Information Center

Hall, Geoffrey B. C.; West, C. Dianne; Szatmari, Peter

2007-01-01

Recent data suggest that subthreshold presentation of emotional information is relayed to the amygdala along subcortical pathways. We examined the effect of backward masked neutral and anxious faces on the social decisions of a group of high functioning children with autism ages 7-13 years and matched controls. Participants were asked to select…

NPTFit: A Code Package for Non-Poissonian Template Fitting

NASA Astrophysics Data System (ADS)

Mishra-Sharma, Siddharth; Rodd, Nicholas L.; Safdi, Benjamin R.

2017-06-01

We present NPTFit, an open-source code package, written in Python and Cython, for performing non-Poissonian template fits (NPTFs). The NPTF is a recently developed statistical procedure for characterizing the contribution of unresolved point sources (PSs) to astrophysical data sets. The NPTF was first applied to Fermi gamma-ray data to provide evidence that the excess of ˜GeV gamma-rays observed in the inner regions of the Milky Way likely arises from a population of sub-threshold point sources, and the NPTF has since found additional applications studying sub-threshold extragalactic sources at high Galactic latitudes. The NPTF generalizes traditional astrophysical template fits to allow for the ability to search for populations of unresolved PSs that may follow a given spatial distribution. NPTFit builds upon the framework of the fluctuation analyses developed in X-ray astronomy, thus it likely has applications beyond those demonstrated with gamma-ray data. The NPTFit package utilizes novel computational methods to perform the NPTF efficiently. The code is available at http://github.com/bsafdi/NPTFit and up-to-date and extensive documentation may be found at http://nptfit.readthedocs.io.

Apolipoprotein A-IV interacts synergistically with melanocortins to reduce food intake.

PubMed

Gotoh, Koro; Liu, Min; Benoit, Stephen C; Clegg, Deborah J; Davidson, W Sean; D'Alessio, David; Seeley, Randy J; Tso, Patrick; Woods, Stephen C

2006-01-01

Apolipoprotein (apo) A-IV is an anorexigenic gastrointestinal peptide that is also synthesized in the hypothalamus. The goal of these experiments was to determine whether apo A-IV interacts with the central melanocortin (MC) system in the control of feeding. The third ventricular (i3vt) administration of a subthreshold dose of apo A-IV (0.5 microg) potentiated i3vt MC-induced (metallothionein-II, 0.03 nmol) suppression of 30-min feeding in Long-Evans rats. A subthreshold dose of the MC antagonist (SHU9119, 0.1 nmol, i3vt) completely attenuated the anorectic effect of i3vt apo A-IV (1.5 microg). The i3vt apo A-IV significantly elevated the expression of c-Fos in neurons of the paraventricular nucleus of the hypothalamus, but not in the arcuate nucleus or median eminence. In addition, c-Fos expression was not colocalized with proopiomelanocortin-positive neurons. These data support a synergistic interaction between apo A-IV and melanocortins that reduces food intake by acting downstream of the arcuate.

Analysis and Enhancement of Low-Light-Level Performance of Photodiode-Type CMOS Active Pixel Images Operated with Sub-Threshold Reset

NASA Technical Reports Server (NTRS)

Pain, Bedabrata; Yang, Guang; Ortiz, Monico; Wrigley, Christopher; Hancock, Bruce; Cunningham, Thomas

2000-01-01

Noise in photodiode-type CMOS active pixel sensors (APS) is primarily due to the reset (kTC) noise at the sense node, since it is difficult to implement in-pixel correlated double sampling for a 2-D array. Signal integrated on the photodiode sense node (SENSE) is calculated by measuring difference between the voltage on the column bus (COL) - before and after the reset (RST) is pulsed. Lower than kTC noise can be achieved with photodiode-type pixels by employing "softreset" technique. Soft-reset refers to resetting with both drain and gate of the n-channel reset transistor kept at the same potential, causing the sense node to be reset using sub-threshold MOSFET current. However, lowering of noise is achieved only at the expense higher image lag and low-light-level non-linearity. In this paper, we present an analysis to explain the noise behavior, show evidence of degraded performance under low-light levels, and describe new pixels that eliminate non-linearity and lag without compromising noise.

Depression and coping in subthreshold eating disorders.

PubMed

Dennard, E Eliot; Richards, C Steven

2013-08-01

The eating disorder literature has sought to understand the role of comorbid psychiatric diagnoses and coping in relation to eating disorders. The present research extends these findings by studying the relationships among depression, coping, and the entire continuum of disordered eating behaviors, with an emphasis on subthreshold eating disorders. 109 undergraduate females completed questionnaires to assess disordered eating symptoms, depressive symptoms, and the use of active and avoidant coping mechanisms. Hypotheses were tested using bivariate linear regression and multivariate linear regression. Results indicated that depression was a significant predictor of disordered eating symptoms after controlling for relationships between depression and coping. Although avoidant coping was positively associated with disordered eating, it was not a significant predictor after controlling for depression and coping. Previous research has found associations between depression and diagnosable eating disorders, and this research extends those findings to the entire continuum of disordered eating. Future research should continue to investigate the predictors and correlates of the disordered eating continuum using more diverse samples. Testing for mediation and moderation among these variables may also be a fruitful area of investigation. Published by Elsevier Ltd.

Anger in the UK Armed Forces: strong association with mental health, childhood antisocial behavior, and combat role.

PubMed

Rona, Roberto J; Jones, Margaret; Hull, Lisa; MacManus, Deirdre; Fear, Nicola T; Wessely, Simon

2015-01-01

We assessed the strength of the association of several mental health problems, childhood difficulties, and combat role with anger, as well as the contribution of these factors to explain anger assessed by population attributable fraction (PAF). A total of 9885 UK service personnel, some of them deployed to Iraq and Afghanistan, participated in the study. There was a strong or intermediate association between cases and subthreshold cases of symptoms of posttraumatic stress disorder, psychological distress, multiple physical symptoms and alcohol misuse, having a combat role, childhood adversity, and childhood antisocial behavior with anger. The PAF for any mental health problem and combat role and childhood difficulties was 0.64 (95% confidence interval [CI], 0.56-0.70) and increased to 0.77 (95% CI, 0.69-0.83) if subthreshold cases were included. Anger is a frequent component of mental disorders; health care professionals need to be aware of the interference of anger in the management of mental illness and that anger infrequently presents as an isolated phenomenon.

[How traumatized are the children of World War II? The relationship of age during flight and forced displacement and current posttraumatic stress symptoms].

PubMed

Wendt, Carolin; Freitag, Simone; Schmidt, Silke

2012-08-01

Traumatic events experienced in childhood can be reactivated in older age. The present study investigates the relation of age during flight and forced displacement within World War II (WWII; 2-7 years, 8-13 years, 14-20 years) and the current occurrence of posttraumatic stress disorder (PTSD). Traumatic events and current posttraumatic stress symptoms were assessed by the Harvard Trauma Questionnaire and the Impact of Event Scale-revised. Mean age of participants (N=169) was 73.76 years (SD=4.18). The eldest group reported most war-related traumatic events. In each age group a one-week-prevalence for a full PTSD of 10-11% was found. The prevalence for both full and subthreshold PTSD was higher for the age group 14-20 years (60.5%) compared to the younger age groups (33-35%). People, who experienced WWII as adolescents, show a dose-response-effect indicated by a higher prevalence for subthreshold PTSD. © Georg Thieme Verlag KG Stuttgart · New York.

Enhancing analog performance and suppression of subthreshold swing using hetero-junctionless double gate TFETs

NASA Astrophysics Data System (ADS)

Chauhan, Sudakar Singh; Sharma, Neha

2017-12-01

This paper proposes hetero-junctionless double gate tunnel field effect transistor (HJLDG-TFETs) for suppression of subthreshold swing (SS) using an InAs compound semiconductor material. The proposed device with high dielectric material, gives an excellent performance when InAs uses at source side. Because of low band gap of 0.36 eV , it reduces the potential barrier height of source channel interface causing higher band to band tunneling. Whereas, Si at the drain side with higher band gap of 1.12 eV , increasing the barrier height of drain channel interface causing lower quantum tunneling. As a result, the proposed device with high-k (HfO2) at 30 nm channel section provides a tremendous characteristics with high ION /IOFF ratio of 2 ×1011 , a point SS of 43.30 mV / decade and moderate SS of 56.75 mV / decade . All the above results show that the proposed device is assured for a low power switching application. The variation in gate supply voltage also analyzed for transconductance property of the device.

Improving Diabetes care through Examining, Advising, and prescribing (IDEA): protocol for a theory-based cluster randomised controlled trial of a multiple behaviour change intervention aimed at primary healthcare professionals

PubMed Central

2014-01-01

Background New clinical research findings may require clinicians to change their behaviour to provide high-quality care to people with type 2 diabetes, likely requiring them to change multiple different clinical behaviours. The present study builds on findings from a UK-wide study of theory-based behavioural and organisational factors associated with prescribing, advising, and examining consistent with high-quality diabetes care. Aim To develop and evaluate the effectiveness and cost of an intervention to improve multiple behaviours in clinicians involved in delivering high-quality care for type 2 diabetes. Design/methods We will conduct a two-armed cluster randomised controlled trial in 44 general practices in the North East of England to evaluate a theory-based behaviour change intervention. We will target improvement in six underperformed clinical behaviours highlighted in quality standards for type 2 diabetes: prescribing for hypertension; prescribing for glycaemic control; providing physical activity advice; providing nutrition advice; providing on-going education; and ensuring that feet have been examined. The primary outcome will be the proportion of patients appropriately prescribed and examined (using anonymised computer records), and advised (using anonymous patient surveys) at 12 months. We will use behaviour change techniques targeting motivational, volitional, and impulsive factors that we have previously demonstrated to be predictive of multiple health professional behaviours involved in high-quality type 2 diabetes care. We will also investigate whether the intervention was delivered as designed (fidelity) by coding audiotaped workshops and interventionist delivery reports, and operated as hypothesised (process evaluation) by analysing responses to theory-based postal questionnaires. In addition, we will conduct post-trial qualitative interviews with practice teams to further inform the process evaluation, and a post-trial economic analysis to estimate the costs of the intervention and cost of service use. Discussion Consistent with UK Medical Research Council guidance and building on previous development research, this pragmatic cluster randomised trial will evaluate the effectiveness of a theory-based complex intervention focusing on changing multiple clinical behaviours to improve quality of diabetes care. Trial registration ISRCTN66498413. PMID:24886606

Can existing mobile apps support healthier food purchasing behaviour? Content analysis of nutrition content, behaviour change theory and user quality integration.

PubMed

Flaherty, Sarah-Jane; McCarthy, Mary; Collins, Alan; McAuliffe, Fionnuala

2018-02-01

To assess the quality of nutrition content and the integration of user quality components and behaviour change theory relevant to food purchasing behaviour in a sample of existing mobile apps. Descriptive comparative analysis of eleven mobile apps comprising an assessment of their alignment with existing evidence on nutrition, behaviour change and user quality, and their potential ability to support healthier food purchasing behaviour. Mobile apps freely available for public use in GoogePlay were assessed and scored according to agreed criteria to assess nutrition content quality and integration of behaviour change theory and user quality components. A sample of eleven mobile apps that met predefined inclusion criteria to ensure relevance and good quality. The quality of the nutrition content varied. Improvements to the accuracy and appropriateness of nutrition content are needed to ensure mobile apps support a healthy behaviour change process and are accessible to a wider population. There appears to be a narrow focus towards behaviour change with an overemphasis on behavioural outcomes and a small number of behaviour change techniques, which may limit effectiveness. A significant effort from the user was required to use the mobile apps appropriately which may negatively influence user acceptability and subsequent utilisation. Existing mobile apps may offer a potentially effective approach to supporting healthier food purchasing behaviour but improvements in mobile app design are required to maximise their potential effectiveness. Engagement of mobile app users and nutrition professionals is recommended to support effective design.

Training practitioners to deliver opportunistic multiple behaviour change counselling in primary care: a cluster randomised trial

PubMed Central

Simpson, Sharon A; Hood, Kerenza; Cohen, David; Pickles, Tim; Spanou, Clio; McCambridge, Jim; Moore, Laurence; Randell, Elizabeth; Alam, M Fasihul; Kinnersley, Paul; Edwards, Adrian; Smith, Christine; Rollnick, Stephen

2013-01-01

Objectives To evaluate the effect of training primary care health professionals in behaviour change counselling on the proportion of patients self reporting change in four risk behaviours (smoking, alcohol use, exercise, and healthy eating). Design Cluster randomised trial with general practices as the unit of randomisation. Setting General practices in Wales. Participants 53 general practitioners and practice nurses from 27 general practices (one each at all but one practice) recruited 1827 patients who screened positive for at least one risky behaviour. Intervention Behaviour change counselling was developed from motivational interviewing to enable clinicians to enhance patients’ motivation to change health related behaviour. Clinicians were trained using a blended learning programme called Talking Lifestyles. Main outcome measures Proportion of patients who reported making beneficial changes in at least one of the four risky behaviours at three months. Results 1308 patients from 13 intervention and 1496 from 14 control practices were approached: 76% and 72% respectively agreed to participate, with 831 (84%) and 996 (92%) respectively screening eligible for an intervention. There was no effect on the primary outcome (beneficial change in behaviour) at three months (362 (44%) v 404 (41%), odds ratio 1.12 (95% CI 0.90 to 1.39)) or on biochemical or biometric measures at 12 months. More patients who had consulted with trained clinicians recalled consultation discussion about a health behaviour (724/795 (91%) v 531/966 (55%), odds ratio 12.44 (5.85 to 26.46)) and intended to change (599/831 (72%) v 491/996 (49%), odds ratio 2.88 (2.05 to 4.05)). More intervention practice patients reported making an attempt to change (328 (39%) v 317 (32%), odds ratio 1.40 (1.15 to 1.70)), a sustained behaviour change at three months (288 (35%) v 280 (28%), odds ratio 1.36 (1.11 to 1.65)), and reported slightly greater improvements in healthy eating at three and 12 months, plus improved activity at 12 months. Training cost £1597 per practice. Discussion Training primary care clinicians in behaviour change counselling using a brief blended learning programme did not increase patients reported beneficial behaviour change at three months or improve biometric and a biochemical measure at 12 months, but it did increase patients’ recollection of discussing behaviour change with their clinicians, intentions to change, attempts to change, and perceptions of having made a lasting change at three months. Enduring behaviour change and improvements in biometric measures are unlikely after a single routine consultation with a clinician trained in behaviour change counselling without additional intervention. Trial registration ISRCTN 22495456 PMID:23512758

Employee innovation behaviour in health care: the influence from management and colleagues.

PubMed

Amo, B W

2006-09-01

This article reports how 'important others' and position in the organizational hierarchy relate to employee innovation behaviour. Empowerment of healthcare workers to engage in innovation behaviour is desired by management in Norwegian municipalities as it is regarded as a way of getting more health care for less money. Innovation behaviour is also desired by nurses' and other healthcare workers' professional organizations of as it is regarded as a way of improving the working conditions of the healthcare worker. The theoretical discussion in this paper includes corporate entrepreneurship, 'important others' and employee innovation behaviour. This article reports on a study concerning empowerment of nurses and other healthcare workers (n = 555) in Norwegian municipalities. The statistical methods used include multiple regressions. The study reveals that there were differences between the nurse (registered nurses), auxiliary nurses (nurse aides) and unskilled healthcare workers concerning how they perceived the opinion of the management and the opinion of the colleagues about how suitable it was to present innovation behaviour at the workplace. Moreover, the different groups of healthcare workers assign different levels of importance to this influence. It is suggested that the findings put forward in this article may lead to an improved understanding of the dynamics behind employee innovation behaviour, and that such knowledge could improve the care provided to the patients, the cost of the care and the working conditions of nurses and other healthcare workers.

Positivity in Practice: Approaches to Improving Perceptions of Young People and Their Involvement in Crime and Anti-Social Behaviour

ERIC Educational Resources Information Center

Martin, Kerry; Hart, Ruth; MacLeod, Shona; Kinder, Kay

2010-01-01

The aim of this research was to investigate the approaches being taken by local authorities (LAs) and partner organisations to improve how young people are perceived, especially in relation to crime and antisocial behaviour. The study also looked at the challenges for and benefits of activities aiming to improve public perceptions of young people,…

Law, evolution and the brain: applications and open questions.

PubMed Central

Jones, Owen D

2004-01-01

This paper discusses several issues at the intersection of law and brain science. It focuses principally on ways in which an improved understanding of how evolutionary processes affect brain function and human behaviour may improve law's ability to regulate behaviour. It explores sample uses of such 'evolutionary analysis in law' and also raises questions about how that analysis might be improved in the future. Among the discussed uses are: (i) clarifying cost-benefit analyses; (ii) providing theoretical foundation and potential predictive power; (iii) assessing comparative effectiveness of legal strategies; and (iv) revealing deep patterns in legal architecture. Throughout, the paper emphasizes the extent to which effective law requires: (i) building effective behavioural models; (ii) integrating life-science perspectives with social-science perspectives; (iii) considering the effects of brain biology on behaviours that law seeks to regulate; and (iv) examining the effects of evolutionary processes on brain design. PMID:15590611

Law, evolution and the brain: applications and open questions.

PubMed

Jones, Owen D

2004-11-29

This paper discusses several issues at the intersection of law and brain science. It focuses principally on ways in which an improved understanding of how evolutionary processes affect brain function and human behaviour may improve law's ability to regulate behaviour. It explores sample uses of such 'evolutionary analysis in law' and also raises questions about how that analysis might be improved in the future. Among the discussed uses are: (i) clarifying cost-benefit analyses; (ii) providing theoretical foundation and potential predictive power; (iii) assessing comparative effectiveness of legal strategies; and (iv) revealing deep patterns in legal architecture. Throughout, the paper emphasizes the extent to which effective law requires: (i) building effective behavioural models; (ii) integrating life-science perspectives with social-science perspectives; (iii) considering the effects of brain biology on behaviours that law seeks to regulate; and (iv) examining the effects of evolutionary processes on brain design.