Processing Code-Switching in Algerian Bilinguals: Effects of Language Use and Semantic Expectancy

PubMed Central

Kheder, Souad; Kaan, Edith

2016-01-01

Using a cross-modal naming paradigm this study investigated the effect of sentence constraint and language use on the expectancy of a language switch during listening comprehension. Sixty-five Algerian bilinguals who habitually code-switch between Algerian Arabic and French (AA-FR) but not between Standard Arabic and French (SA-FR) listened to sentence fragments and named a visually presented French target NP out loud. Participants’ speech onset times were recorded. The sentence context was either highly semantically constraining toward the French NP or not. The language of the sentence context was either in Algerian Arabic or in Standard Arabic, but the target NP was always in French, thus creating two code-switching contexts: a typical and recurrent code-switching context (AA-FR) and a non-typical code-switching context (SA-FR). Results revealed a semantic constraint effect indicating that the French switches were easier to process in the high compared to the low-constraint context. In addition, the effect size of semantic constraint was significant in the more typical code-switching context (AA-FR) suggesting that language use influences the processing of switching between languages. The effect of semantic constraint was also modulated by code-switching habits and the proficiency of L2 French. Semantic constraint was reduced in bilinguals who frequently code-switch and in bilinguals with high proficiency in French. Results are discussed with regards to the bilingual interactive activation model (Dijkstra and Van Heuven, 2002) and the control process model of code-switching (Green and Wei, 2014). PMID:26973559

Noise-driven switching and chaotic itinerancy among dynamic states in a three-mode intracavity second-harmonic generation laser operating on a Λ transition

NASA Astrophysics Data System (ADS)

Otsuka, Kenju; Ohtomo, Takayuki; Maniwa, Tsuyoshi; Kawasaki, Hazumi; Ko, Jing-Yuan

2003-09-01

We studied the antiphase self-pulsation in a globally coupled three-mode laser operating in different optical spectrum configurations. We observed locking of modal pulsation frequencies, quasiperiodicity, clustering behaviors, and chaos, resulting from the nonlinear interaction among modes. The robustness of [p:q:r] three-frequency locking states and quasiperiodic oscillations against residual noise has been examined by using joint time-frequency analysis of long-term experimental time series. Two sharply antithetical types of switching behaviors among different dynamic states were observed during temporal evolutions; noise-driven switching and self-induced switching, which manifests itself in chaotic itinerancy. The modal interplay behind observed behaviors was studied by using the statistical dynamic quantity of the information circulation. Well-organized information flows among modes, which correspond to the number of degeneracies of modal pulsation frequencies, were found to be established in accordance with the inherent antiphase dynamics. Observed locking behaviors, quasiperiodic motions, and chaotic itinerancy were reproduced by numerical simulation of the model equations.

Examining age-related differences in auditory attention control using a task-switching procedure.

PubMed

Lawo, Vera; Koch, Iring

2014-03-01

Using a novel task-switching variant of dichotic selective listening, we examined age-related differences in the ability to intentionally switch auditory attention between 2 speakers defined by their sex. In our task, young (M age = 23.2 years) and older adults (M age = 66.6 years) performed a numerical size categorization on spoken number words. The task-relevant speaker was indicated by a cue prior to auditory stimulus onset. The cuing interval was either short or long and varied randomly trial by trial. We found clear performance costs with instructed attention switches. These auditory attention switch costs decreased with prolonged cue-stimulus interval. Older adults were generally much slower (but not more error prone) than young adults, but switching-related effects did not differ across age groups. These data suggest that the ability to intentionally switch auditory attention in a selective listening task is not compromised in healthy aging. We discuss the role of modality-specific factors in age-related differences.

Comparing Mortality of Peritoneal and Hemodialysis Patients in the First 2 Years of Dialysis Therapy: A Marginal Structural Model Analysis

PubMed Central

Lukowsky, Lilia R.; Mehrotra, Rajnish; Kheifets, Leeka; Arah, Onyebuchi A.; Nissenson, Allen R.

2013-01-01

Summary Background and objectives There are conflicting research results about the survival differences between hemodialysis and peritoneal dialysis, especially during the first 2 years of dialysis treatment. Given the challenges of conducting randomized trials, differential rates of modality switch and transplantation, and time-varying confounding in cohort data during the first years of dialysis treatment, use of novel analytical techniques in observational cohorts can help examine the peritoneal dialysis versus hemodialysis survival discrepancy. Design, setting, participants, & measurements This study examined a cohort of incident dialysis patients who initiated dialysis in DaVita dialysis facilities between July of 2001 and June of 2004 and were followed for 24 months. This study used the causal modeling technique of marginal structural models to examine the survival differences between peritoneal dialysis and hemodialysis over the first 24 months, accounting for modality change, differential transplantation rates, and detailed time-varying laboratory measurements. Results On dialysis treatment day 90, there were 23,718 incident dialysis—22,360 hemodialysis and 1,358 peritoneal dialysis—patients. Incident peritoneal dialysis patients were younger, had fewer comorbidities, and were nine and three times more likely to switch dialysis modality and receive kidney transplantation over the 2-year period, respectively, compared with hemodialysis patients. In marginal structural models analyses, peritoneal dialysis was associated with persistently greater survival independent of the known confounders, including dialysis modality switch and transplant censorship (i.e., death hazard ratio of 0.52 [95% confidence limit 0.34–0.80]). Conclusions Peritoneal dialysis seems to be associated with 48% lower mortality than hemodialysis over the first 2 years of dialysis therapy independent of modality switches or differential transplantation rates. PMID:23307879

Comparing mortality of peritoneal and hemodialysis patients in the first 2 years of dialysis therapy: a marginal structural model analysis.

PubMed

Lukowsky, Lilia R; Mehrotra, Rajnish; Kheifets, Leeka; Arah, Onyebuchi A; Nissenson, Allen R; Kalantar-Zadeh, Kamyar

2013-04-01

There are conflicting research results about the survival differences between hemodialysis and peritoneal dialysis, especially during the first 2 years of dialysis treatment. Given the challenges of conducting randomized trials, differential rates of modality switch and transplantation, and time-varying confounding in cohort data during the first years of dialysis treatment, use of novel analytical techniques in observational cohorts can help examine the peritoneal dialysis versus hemodialysis survival discrepancy. This study examined a cohort of incident dialysis patients who initiated dialysis in DaVita dialysis facilities between July of 2001 and June of 2004 and were followed for 24 months. This study used the causal modeling technique of marginal structural models to examine the survival differences between peritoneal dialysis and hemodialysis over the first 24 months, accounting for modality change, differential transplantation rates, and detailed time-varying laboratory measurements. On dialysis treatment day 90, there were 23,718 incident dialysis-22,360 hemodialysis and 1,358 peritoneal dialysis-patients. Incident peritoneal dialysis patients were younger, had fewer comorbidities, and were nine and three times more likely to switch dialysis modality and receive kidney transplantation over the 2-year period, respectively, compared with hemodialysis patients. In marginal structural models analyses, peritoneal dialysis was associated with persistently greater survival independent of the known confounders, including dialysis modality switch and transplant censorship (i.e., death hazard ratio of 0.52 [95% confidence limit 0.34-0.80]). Peritoneal dialysis seems to be associated with 48% lower mortality than hemodialysis over the first 2 years of dialysis therapy independent of modality switches or differential transplantation rates.

A multiple camera tongue switch for a child with severe spastic quadriplegic cerebral palsy.

PubMed

Leung, Brian; Chau, Tom

2010-01-01

The present study proposed a video-based access technology that facilitated a non-contact tongue protrusion access modality for a 7-year-old boy with severe spastic quadriplegic cerebral palsy (GMFCS level 5). The proposed system featured a centre camera and two peripheral cameras to extend coverage of the frontal face view of this user for longer durations. The child participated in a descriptive case study. The participant underwent 3 months of tongue protrusion training while the multiple camera tongue switch prototype was being prepared. Later, the participant was brought back for five experiment sessions where he worked on a single-switch picture matching activity, using the multiple camera tongue switch prototype in a controlled environment. The multiple camera tongue switch achieved an average sensitivity of 82% and specificity of 80%. In three of the experiment sessions, the peripheral cameras were associated with most of the true positive switch activations. These activations would have been missed by a centre-camera-only setup. The study demonstrated proof-of-concept of a non-contact tongue access modality implemented by a video-based system involving three cameras and colour video processing.

Persistent Flagellate Hyperpigmentation

DTIC Science & Technology

2017-04-28

hydroquinone), laser modalities such as Q-switched 755/1064 nm lasers , and ablative C02 resurfacing lasers . In addition, patients should be counseled on...the importance of UV protection. The patient was treated with each of these treatment modal ities with minimal improvement. Resources: 1. Lee HY

Electro-optical logic gates based on graphene-silicon waveguides

NASA Astrophysics Data System (ADS)

Chen, Weiwei; Yang, Longzhi; Wang, Pengjun; Zhang, Yawei; Zhou, Liqiang; Yang, Tianjun; Wang, Yang; Yang, Jianyi

2016-08-01

In this paper, designs of electro-optical AND/NAND, OR/ NOR, XOR/XNOR logic gates based on cascaded silicon graphene switches and regular 2×1 multimode interference combiners are presented. Each switch consists of a Mach-Zehnder interferometer in which silicon slot waveguides embedded with graphene flakes are designed for phase shifters. High-speed switching function is achieved by applying an electrical signal to tune the Fermi levels of graphene flakes causing the variation of modal effective index. Calculation results show the crosstalk in the proposed optical switch is lower than -22.9 dB within a bandwidth from 1510 nm to 1600 nm. The designed six electro-optical logic gates with the operation speed of 10 Gbit/s have a minimum extinction ratio of 35.6 dB and a maximum insertion loss of 0.21 dB for transverse electric modes at 1.55 μm.

The benefits of endurance exercise and Tai Chi Chuan for the task-switching aspect of executive function in older adults: an ERP study.

PubMed

Fong, Dong-Yang; Chi, Li-Kang; Li, Fuzhong; Chang, Yu-Kai

2014-01-01

This study was designed to determine the relationship between physical activity and the task-switching aspect of executive function by investigating the modulating roles of age, modality of physical activity, and type of cognitive function using behavioral and event-related potential (ERP) assessments. Sixty-four participants were assigned to one of four groups based on age and history of physical activity: older adults performing endurance exercise (OEE), older adults practicing Tai Chi Chuan (OTC), older adults with a sedentary lifestyle (OSL), and young adults (YA). Study participants completed a task-switching task under homogeneous and heterogeneous conditions while ERPs were recorded. The results revealed that YA had shortest reaction times compared with the three older adults groups, with OSL exhibiting the longest reaction time. YA also exhibited shorter P3 latency than OSL. No differences were observed in P3 amplitude between YA, OEE, and OTC; however, all three groups had significantly larger P3 amplitude compared with OSL in both task conditions. In conclusion, age and participation in physical activity influence the relationship between physical activity and task-switching, and a positive relationship was observed regardless of the modality of physical activity and type of cognitive function. Our ERP findings support the model of the scaffolding theory of aging and cognition (STAC) and suggest that regular participation in endurance exercise and Tai Chi Chuan may have equivalent beneficial effects on cognition at the behavioral and neuroelectric levels.

The benefits of endurance exercise and Tai Chi Chuan for the task-switching aspect of executive function in older adults: an ERP study

PubMed Central

Fong, Dong-Yang; Chi, Li-Kang; Li, Fuzhong; Chang, Yu-Kai

2014-01-01

This study was designed to determine the relationship between physical activity and the task-switching aspect of executive function by investigating the modulating roles of age, modality of physical activity, and type of cognitive function using behavioral and event-related potential (ERP) assessments. Sixty-four participants were assigned to one of four groups based on age and history of physical activity: older adults performing endurance exercise (OEE), older adults practicing Tai Chi Chuan (OTC), older adults with a sedentary lifestyle (OSL), and young adults (YA). Study participants completed a task-switching task under homogeneous and heterogeneous conditions while ERPs were recorded. The results revealed that YA had shortest reaction times compared with the three older adults groups, with OSL exhibiting the longest reaction time. YA also exhibited shorter P3 latency than OSL. No differences were observed in P3 amplitude between YA, OEE, and OTC; however, all three groups had significantly larger P3 amplitude compared with OSL in both task conditions. In conclusion, age and participation in physical activity influence the relationship between physical activity and task-switching, and a positive relationship was observed regardless of the modality of physical activity and type of cognitive function. Our ERP findings support the model of the scaffolding theory of aging and cognition (STAC) and suggest that regular participation in endurance exercise and Tai Chi Chuan may have equivalent beneficial effects on cognition at the behavioral and neuroelectric levels. PMID:25389403

Cross-modal Savings in the Contralateral Eyelid Conditioned Response

PubMed Central

Campolattaro, Matthew M.; Buss, Eric W.; Freeman, John H.

2015-01-01

The present experiment monitored bilateral eyelid responses during eyeblink conditioning in rats trained with a unilateral unconditioned stimulus (US). Three groups of rats were used to determine if cross-modal savings occurs when the location of the US is switched from one eye to the other. Rats in each group first received paired or unpaired eyeblink conditioning with a conditioned stimulus (tone or light; CS) and a unilateral periorbital electrical stimulation US. All rats were subsequently given paired training, but with the US location (Group 1), CS modality (Group 2), or US location and CS modality (Group 3) changed. Changing the location of the US alone resulted in an immediate transfer of responding in both eyelids (Group 1) in rats that received paired training prior to the transfer session. Rats in groups 2 and 3 that initially received paired training showed facilitated learning to the new CS modality during the transfer sessions, indicating that cross-modal savings occurs whether or not the location of the US is changed. All rats that were initially given unpaired training acquired conditioned eyeblink responses similar to de novo acquisition rate during the transfer sessions. Savings of CR incidence was more robust than savings of CR amplitude when the US switched sides, a finding that has implications for elucidating the neural mechanisms of cross-modal savings. PMID:26501170

Turning the gene tap off; implications of regulating gene expression for cancer therapeutics

PubMed Central

Curtin, James F.; Candolfi, Marianela; Xiong, Weidong; Lowenstein, Pedro R.; Castro, Maria G.

2008-01-01

Cancer poses a tremendous therapeutic challenge worldwide, highlighting the critical need for developing novel therapeutics. A promising cancer treatment modality is gene therapy, which is a form of molecular medicine designed to introduce into target cells genetic material with therapeutic intent. Anticancer gene therapy strategies currently used in preclinical models, and in some cases in the clinic, include proapoptotic genes, oncolytic/replicative vectors, conditional cytotoxic approaches, inhibition of angiogenesis, inhibition of growth factor signaling, inactivation of oncogenes, inhibition of tumor invasion and stimulation of the immune system. The translation of these novel therapeutic modalities from the preclinical setting to the clinic has been driven by encouraging preclinical efficacy data and advances in gene delivery technologies. One area of intense research involves the ability to accurately regulate the levels of therapeutic gene expression to achieve enhanced efficacy and provide the capability to switch gene expression off completely if adverse side effects should arise. This feature could also be implemented to switch gene expression off when a successful therapeutic outcome ensues. Here, we will review recent developments related to the engineering of transcriptional switches within gene delivery systems, which could be implemented in clinical gene therapy applications directed at the treatment of cancer. PMID:18347132

Waveguide-based electro-absorption modulator performance: comparative analysis

NASA Astrophysics Data System (ADS)

Amin, Rubab; Khurgin, Jacob B.; Sorger, Volker J.

2018-06-01

Electro-optic modulation is a key function for data communication. Given the vast amount of data handled, understanding the intricate physics and trade-offs of modulators on-chip allows revealing performance regimes not explored yet. Here we show a holistic performance analysis for waveguide-based electro-absorption modulators. Our approach centers around material properties revealing obtainable optical absorption leading to effective modal cross-section, and material broadening effects. Taken together both describe the modulator physical behavior entirely. We consider a plurality of material modulation classes to include two-level absorbers such as quantum dots, free carrier accumulation or depletion such as ITO or Silicon, two-dimensional electron gas in semiconductors such as quantum wells, Pauli blocking in Graphene, and excitons in two-dimensional atomic layered materials such as found in transition metal dichalcogendies. Our results show that reducing the modal area generally improves modulator performance defined by the amount of induced electrical charge, and hence the energy-per-bit function, required switching the signal. We find that broadening increases the amount of switching charge needed. While some material classes allow for reduced broadening such as quantum dots and 2-dimensional materials due to their reduced Coulomb screening leading to increased oscillator strengths, the sharpness of broadening is overshadowed by thermal effects independent of the material class. Further we find that plasmonics allows the switching charge and energy-per-bit function to be reduced by about one order of magnitude compared to bulk photonics. This analysis is aimed as a guide for the community to predict anticipated modulator performance based on both existing and emerging materials.

Modality Switching Cost during Property Verification by 7 Years of Age

ERIC Educational Resources Information Center

Ambrosi, Solene; Kalenine, Solene; Blaye, Agnes; Bonthoux, Francoise

2011-01-01

Recent studies in neuroimagery and cognitive psychology support the view of sensory-motor based knowledge: when processing an object concept, neural systems would re-enact previous experiences with this object. In this experiment, a conceptual switching cost paradigm derived from Pecher, Zeelenberg, and Barsalou (2003, 2004) was used to…

An eye movement analysis of the effect of interruption modality on primary task resumption.

PubMed

Ratwani, Raj; Trafton, J Gregory

2010-06-01

We examined the effect of interruption modality (visual or auditory) on primary task (visual) resumption to determine which modality was the least disruptive. Theories examining interruption modality have focused on specific periods of the interruption timeline. Preemption theory has focused on the switch from the primary task to the interrupting task. Multiple resource theory has focused on interrupting tasks that are to be performed concurrently with the primary task. Our focus was on examining how interruption modality influences task resumption.We leverage the memory-for-goals theory, which suggests that maintaining an associative link between environmental cues and the suspended primary task goal is important for resumption. Three interruption modality conditions were examined: auditory interruption with the primary task visible, auditory interruption with a blank screen occluding the primary task, and a visual interruption occluding the primary task. Reaction time and eye movement data were collected. The auditory condition with the primary task visible was the least disruptive. Eye movement data suggest that participants in this condition were actively maintaining an associative link between relevant environmental cues on the primary task interface and the suspended primary task goal during the interruption. These data suggest that maintaining cue association is the important factor for reducing the disruptiveness of interruptions, not interruption modality. Interruption-prone computing environments should be designed to allow for the user to have access to relevant primary task cues during an interruption to minimize disruptiveness.

Age-Related Changes in the Ability to Switch between Temporal and Spatial Attention.

PubMed

Callaghan, Eleanor; Holland, Carol; Kessler, Klaus

2017-01-01

Background : Identifying age-related changes in cognition that contribute towards reduced driving performance is important for the development of interventions to improve older adults' driving and prolong the time that they can continue to drive. While driving, one is often required to switch from attending to events changing in time, to distribute attention spatially. Although there is extensive research into both spatial attention and temporal attention and how these change with age, the literature on switching between these modalities of attention is limited within any age group. Methods : Age groups (21-30, 40-49, 50-59, 60-69 and 70+ years) were compared on their ability to switch between detecting a target in a rapid serial visual presentation (RSVP) stream and detecting a target in a visual search display. To manipulate the cost of switching, the target in the RSVP stream was either the first item in the stream (Target 1st), towards the end of the stream (Target Mid), or absent from the stream (Distractor Only). Visual search response times and accuracy were recorded. Target 1st trials behaved as no-switch trials, as attending to the remaining stream was not necessary. Target Mid and Distractor Only trials behaved as switch trials, as attending to the stream to the end was required. Results : Visual search response times (RTs) were longer on "Target Mid" and "Distractor Only" trials in comparison to "Target 1st" trials, reflecting switch-costs. Larger switch-costs were found in both the 40-49 and 60-69 years group in comparison to the 21-30 years group when switching from the Target Mid condition. Discussion : Findings warrant further exploration as to whether there are age-related changes in the ability to switch between these modalities of attention while driving. If older adults display poor performance when switching between temporal and spatial attention while driving, then the development of an intervention to preserve and improve this ability would be beneficial.

Throwing out the rules: anticipatory alpha-band oscillatory attention mechanisms during task-set reconfigurations.

PubMed

Foxe, John J; Murphy, Jeremy W; De Sanctis, Pierfilippo

2014-06-01

We assessed the role of alpha-band oscillatory activity during a task-switching design that required participants to switch between an auditory and a visual task, while task-relevant audiovisual inputs were simultaneously presented. Instructional cues informed participants which task to perform on a given trial and we assessed alpha-band power in the short 1.35-s period intervening between the cue and the task-imperative stimuli, on the premise that attentional biasing mechanisms would be deployed to resolve competition between the auditory and visual inputs. Prior work had shown that alpha-band activity was differentially deployed depending on the modality of the cued task. Here, we asked whether this activity would, in turn, be differentially deployed depending on whether participants had just made a switch of task or were being asked to simply repeat the task. It is well established that performance speed and accuracy are poorer on switch than on repeat trials. Here, however, the use of instructional cues completely mitigated these classic switch-costs. Measures of alpha-band synchronisation and desynchronisation showed that there was indeed greater and earlier differential deployment of alpha-band activity on switch vs. repeat trials. Contrary to our hypothesis, this differential effect was entirely due to changes in the amount of desynchronisation observed during switch and repeat trials of the visual task, with more desynchronisation over both posterior and frontal scalp regions during switch-visual trials. These data imply that particularly vigorous, and essentially fully effective, anticipatory biasing mechanisms resolved the competition between competing auditory and visual inputs when a rapid switch of task was required. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Switching Between Everyday and Scientific Language

NASA Astrophysics Data System (ADS)

Blown, Eric J.; Bryce, Tom G. K.

2017-06-01

The research reported here investigated the everyday and scientific repertoires of children involved in semi-structured, Piagetian interviews carried out to check their understanding of dynamic astronomical concepts like daytime and night-time. It focused on the switching taking place between embedded and disembedded thinking; on the imagery which subjects referred to in their verbal dialogue and their descriptions of drawings and play-dough models of the Earth, Sun and Moon; and it examined the prevalence and character of animism and figurative speech in children's thinking. Five hundred and thirty-nine children (aged 3-18) from Wairarapa in New Zealand (171 boys and 185 girls) and Changchun in China (99 boys and 84 girls) took part in the study. Modified ordinal scales for the relevant concept categories were used to classify children's responses and data from each age group (with numbers balanced as closely as practicable by culture and gender) analysed with Kolmogorov-Smirnov two-sample tests (at an alpha level of 0.05). Although, in general, there was consistency of dynamic concepts within and across media and their associated modalities in keeping with the theory of conceptual coherence (see Blown and Bryce 2010; Bryce and Blown 2016), there were several cases of inter-modal and intra-modal switching in both cultures. Qualitative data from the interview protocols revealed how children switch between everyday and scientific language (in both directions) and use imagery in response to questioning. The research indicates that children's grasp of scientific ideas in this field may ordinarily be under-estimated if one only goes by formal scientific expression and vocabulary.

Shared and distinct factors driving attention and temporal processing across modalities

PubMed Central

Berry, Anne S.; Li, Xu; Lin, Ziyong; Lustig, Cindy

2013-01-01

In addition to the classic finding that “sounds are judged longer than lights,” the timing of auditory stimuli is often more precise and accurate than is the timing of visual stimuli. In cognitive models of temporal processing, these modality differences are explained by positing that auditory stimuli more automatically capture and hold attention, more efficiently closing an attentional switch that allows the accumulation of pulses marking the passage of time (Block & Zakay, 1997; Meck, 1991; Penney, 2003). However, attention is a multifaceted construct, and there has been little attempt to determine which aspects of attention may be related to modality effects. We used visual and auditory versions of the Continuous Temporal Expectancy Task (CTET; O'Connell et al., 2009) a timing task previously linked to behavioral and electrophysiological measures of mind-wandering and attention lapses, and tested participants with or without the presence of a video distractor. Performance in the auditory condition was generally superior to that in the visual condition, replicating standard results in the timing literature. The auditory modality was also less affected by declines in sustained attention indexed by declines in performance over time. In contrast, distraction had an equivalent impact on performance in the two modalities. Analysis of individual differences in performance revealed further differences between the two modalities: Poor performance in the auditory condition was primarily related to boredom whereas poor performance in the visual condition was primarily related to distractibility. These results suggest that: 1) challenges to different aspects of attention reveal both modality-specific and nonspecific effects on temporal processing, and 2) different factors drive individual differences when testing across modalities. PMID:23978664

Age-Related Changes in the Ability to Switch between Temporal and Spatial Attention

PubMed Central

Callaghan, Eleanor; Holland, Carol; Kessler, Klaus

2017-01-01

Background: Identifying age-related changes in cognition that contribute towards reduced driving performance is important for the development of interventions to improve older adults’ driving and prolong the time that they can continue to drive. While driving, one is often required to switch from attending to events changing in time, to distribute attention spatially. Although there is extensive research into both spatial attention and temporal attention and how these change with age, the literature on switching between these modalities of attention is limited within any age group. Methods: Age groups (21–30, 40–49, 50–59, 60–69 and 70+ years) were compared on their ability to switch between detecting a target in a rapid serial visual presentation (RSVP) stream and detecting a target in a visual search display. To manipulate the cost of switching, the target in the RSVP stream was either the first item in the stream (Target 1st), towards the end of the stream (Target Mid), or absent from the stream (Distractor Only). Visual search response times and accuracy were recorded. Target 1st trials behaved as no-switch trials, as attending to the remaining stream was not necessary. Target Mid and Distractor Only trials behaved as switch trials, as attending to the stream to the end was required. Results: Visual search response times (RTs) were longer on “Target Mid” and “Distractor Only” trials in comparison to “Target 1st” trials, reflecting switch-costs. Larger switch-costs were found in both the 40–49 and 60–69 years group in comparison to the 21–30 years group when switching from the Target Mid condition. Discussion: Findings warrant further exploration as to whether there are age-related changes in the ability to switch between these modalities of attention while driving. If older adults display poor performance when switching between temporal and spatial attention while driving, then the development of an intervention to preserve and improve this ability would be beneficial. PMID:28261088

Multi-Gigabit Fiber Optic Wide Area Network Development.

DTIC Science & Technology

1991-07-01

to propagate, no modal dispersion can occur. In multimode fiber , a parabolic index profile across the core is often used so that mode travel times are...In the fiber plant, such as connectors, splices couplers, splitters, switches, tunable filters , wavelength division multiplexers and demultiplexers...losses are much higher, at around 0.5 dB, and are usually avoided in long-haul systems. 30 Some fiber plant components have a filtering effect on the

Beneficial Effect of Low Fluence 1,064 nm Q-Switched Neodymium:Yttrium-Aluminum-Garnet Laser in the Treatment of Senile Lentigo

PubMed Central

Nam, Jae-Hui; Kim, Han-Saem; Lee, Ga-Young

2017-01-01

Background Low fluence 1,064 nm Q-switched (QS) Neodymium:Yttrium-Aluminum-Garnet (Nd:YAG) laser treatment, also known as laser toning, is widely used for pigmentary disorders. There has been no reliable evaluation of the effect of low fluence 1,064 nm QS Nd:YAG laser for senile lentigo. Objective To investigate the beneficial effect of low fluence 1,064 nm QS Nd:YAG laser in the treatment of senile lentigo on the face. Methods A retrospective review was conducted on patients treated only with repetitive low fluence 1,064 nm QS Nd:YAG laser. Among them, 12 patients with multiple senile lentigines before treatment were included. All side effects were recorded to assess the safety of the modality. Results Mean age was 56.1±7.8 years old and male-to-female ratio was 1:11. Mean treatment fluence was 1.62±0.16 J/cm2 and mean total treatment session was 8.8±2.6. Mean interval period between each session was 28.0±11.4 days and mean treatment session to reach marked and near total improvement was 8.7±2.8. At the final visit, seven of 12 (58.3%) patients reached marked and near total improvement, and three of 12 (25.0%) reached moderate improvement. No side effects occurred. Conclusion Repetitive low fluence 1,064 nm QS Nd:YAG laser treatment may be an effective and safe optional modality for senile lentigo. PMID:28761290

Nanox: a miniature mechanical stress rig designed for near-field X-ray diffraction imaging techniques.

PubMed

Gueninchault, N; Proudhon, H; Ludwig, W

2016-11-01

Multi-modal characterization of polycrystalline materials by combined use of three-dimensional (3D) X-ray diffraction and imaging techniques may be considered as the 3D equivalent of surface studies in the electron microscope combining diffraction and other imaging modalities. Since acquisition times at synchrotron sources are nowadays compatible with four-dimensional (time lapse) studies, suitable mechanical testing devices are needed which enable switching between these different imaging modalities over the course of a mechanical test. Here a specifically designed tensile device, fulfilling severe space constraints and permitting to switch between X-ray (holo)tomography, diffraction contrast tomography and topotomography, is presented. As a proof of concept the 3D characterization of an Al-Li alloy multicrystal by means of diffraction contrast tomography is presented, followed by repeated topotomography characterization of one selected grain at increasing levels of deformation. Signatures of slip bands and sudden lattice rotations inside the grain have been shown by means of in situ topography carried out during the load ramps, and diffraction spot peak broadening has been monitored throughout the experiment.

Nanox: a miniature mechanical stress rig designed for near-field X-ray diffraction imaging techniques

PubMed Central

Gueninchault, N.; Proudhon, H.; Ludwig, W.

2016-01-01

Multi-modal characterization of polycrystalline materials by combined use of three-dimensional (3D) X-ray diffraction and imaging techniques may be considered as the 3D equivalent of surface studies in the electron microscope combining diffraction and other imaging modalities. Since acquisition times at synchrotron sources are nowadays compatible with four-dimensional (time lapse) studies, suitable mechanical testing devices are needed which enable switching between these different imaging modalities over the course of a mechanical test. Here a specifically designed tensile device, fulfilling severe space constraints and permitting to switch between X-ray (holo)tomography, diffraction contrast tomography and topotomography, is presented. As a proof of concept the 3D characterization of an Al–Li alloy multicrystal by means of diffraction contrast tomography is presented, followed by repeated topotomography characterization of one selected grain at increasing levels of deformation. Signatures of slip bands and sudden lattice rotations inside the grain have been shown by means of in situ topography carried out during the load ramps, and diffraction spot peak broadening has been monitored throughout the experiment. PMID:27787253

Light and laser treatment modalities for disseminated superficial actinic porokeratosis: a systematic review.

PubMed

Aird, Gregory A; Sitenga, Jenna L; Nguyen, Austin Huy; Vaudreuil, Adam; Huerter, Christopher J

2017-05-01

Treatment of disseminated superficial actinic porokeratosis (DSAP) is poorly standardized. The present review seeks to comprehensively discuss the potential for laser and light modalities in the treatment of DSAP. A systematic review of light and laser treatment modalities was conducted to include 26 cases of patients with DSAP. Systematic review resulted in 14 articles to be included. Photodynamic therapy (PDT) overall was the least successful treatment modality, with clinical improvement seen in a minority of patients (MAL-PDT: N = 9 patients, 33.3% showed improvement; ALA-PDT: N = 3 patients, 0% improvement; hypericin-PDT: N = 2 patients, 0% improvement) after numerous post-procedural side effects of hyperpigmentation, inflammation, erythema, and discomfort. Overall, in the available reports, PDT demonstrates poor outcomes with greater incidence of side effects. The response rates of DSAP lesions treated with lasers were as follows: (Q-switched ruby lasers: N = 2, 100%; CO 2 laser: N = 1, 100%; PDT and CO 2 combination therapy: N = 2, 0-50%; erbium and neodymium YAG lasers: N = 2, 100%; fractional 1927-nm thulium fiber lasers: N = 2, 100%; Grenz rays: N = 1, 100%; and fractional photothermolysis: N = 2, 100%). The side effects of laser therapy were minimal and included mild erythema, slight hyperpigmentation, and moderate edema. Laser therapy is a promising treatment option for DSAP with an excellent side effect profile. However, higher power studies are required to determine optimal guidelines for laser treatment of DSAP.

Combination of CO2 and Q-switched Nd:YAG lasers is more effective than Q-switched Nd:YAG laser alone for eyebrow tattoo removal.

PubMed

Radmanesh, Mohammad; Rafiei, Zohreh

2015-04-01

The eyebrow tattoo removal using Q-switched lasers is usually prolonged. Other modalities may be required to enhance the efficacy and shorten the treatment course. To compare the efficacy of Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser alone versus combination of Q-switched Nd:YAG and Ultrapulse CO2 lasers for eyebrow tattoo removal after a single session. After local anesthesia, the right eyebrow of 20 patients was treated with Ultrapulse CO2 laser with the parameters of 4 J/cm(2) and 3.2 J/cm(2) for the first and the second passes. Both eyebrows were then treated with 1064-nm and 532-nm Q-switched Nd:YAG laser. The spot size and pulse duration were 3 mm and 5 nanoseconds for both wavelengths, and the fluence was 7 J/cm(2) for 1064 nm and 3 J/cm (2) for 532 nm. The side treated with combination of Q-switched Nd:YAG and CO2 lasers improved 75-100% in 6 of 20 patients versus only 1 of 20 in the side treated with Q-switched Nd:YAG alone. Similarly, the right side in 13 of 20 patients showed more than 50% improvement with combination therapy versus the left side (the monotherapy side), where only 6 of 20 cases showed more than 50% improvement. The Mann-Whitney test was 2.85 for the right side and 1.95 for the left side (P value = 0.007). Using Ultra pulse CO2 laser enhances the efficacy of Q-switched Nd:YAG laser in eyebrow tattoo removal.

Intentional preparation of auditory attention-switches: Explicit cueing and sequential switch-predictability.

PubMed

Seibold, Julia C; Nolden, Sophie; Oberem, Josefa; Fels, Janina; Koch, Iring

2018-06-01

In an auditory attention-switching paradigm, participants heard two simultaneously spoken number-words, each presented to one ear, and decided whether the target number was smaller or larger than 5 by pressing a left or right key. An instructional cue in each trial indicated which feature had to be used to identify the target number (e.g., female voice). Auditory attention-switch costs were found when this feature changed compared to when it repeated in two consecutive trials. Earlier studies employing this paradigm showed mixed results when they examined whether such cued auditory attention-switches can be prepared actively during the cue-stimulus interval. This study systematically assessed which preconditions are necessary for the advance preparation of auditory attention-switches. Three experiments were conducted that controlled for cue-repetition benefits, modality switches between cue and stimuli, as well as for predictability of the switch-sequence. Only in the third experiment, in which predictability for an attention-switch was maximal due to a pre-instructed switch-sequence and predictable stimulus onsets, active switch-specific preparation was found. These results suggest that the cognitive system can prepare auditory attention-switches, and this preparation seems to be triggered primarily by the memorised switching-sequence and valid expectations about the time of target onset.

Q-switched Nd: YAG laser versus trichloroacetic acid peeling in the treatment of melasma among Egyptian patients.

PubMed

Moubasher, Alaa E A; Youssef, Eman M K; Abou-Taleb, Doaa A E

2014-08-01

Melasma is a common disorder of facial hyperpigmentation that is often resistant to treatment. To evaluate the efficacy of trichloroacetic acid (TCA) peeling in comparison with double frequency Q-switched neodymium-doped:yttrium aluminum garnet (QS-Nd:YAG) laser in the treatment of melasma. Sixty-five adult Egyptian female patients with melasma were enrolled in this study. Wood light was used for determination of the histological type of melasma. The patients were divided into 4 groups according to treatment modalities: peeling with different concentrations of TCA and double frequency QS-Nd:YAG laser. Trichloroacetic acid peeling was performed every 2 weeks up to 8 sessions, whereas laser treatment was performed every month up to 6 sessions. Melasma area and severity index (MASI) score was used before and after treatment for evaluation. Improvement percentage of MASI score was significantly higher among patients treated with TCA 25% (p < .001). Epidermal type of melasma was significantly improved compared with the dermal type (p = .0029). Q-switched neodymium-doped:yttrium aluminum garnet laser showed the highest incidence of postinflammatory hyperpigmentation (53.3%). Trichloroacetic acid peeling is effective in the treatment of melasma, TCA 25% was the most effective concentration. Q-switched neodymium-doped:yttrium aluminum garnet laser is not recommended in the treatment of melasma because it was associated with the highest incidence of complications.

Spatial working memory for locations specified by vision and audition: testing the amodality hypothesis.

PubMed

Loomis, Jack M; Klatzky, Roberta L; McHugh, Brendan; Giudice, Nicholas A

2012-08-01

Spatial working memory can maintain representations from vision, hearing, and touch, representations referred to here as spatial images. The present experiment addressed whether spatial images from vision and hearing that are simultaneously present within working memory retain modality-specific tags or are amodal. Observers were presented with short sequences of targets varying in angular direction, with the targets in a given sequence being all auditory, all visual, or a sequential mixture of the two. On two thirds of the trials, one of the locations was repeated, and observers had to respond as quickly as possible when detecting this repetition. Ancillary detection and localization tasks confirmed that the visual and auditory targets were perceptually comparable. Response latencies in the working memory task showed small but reliable costs in performance on trials involving a sequential mixture of auditory and visual targets, as compared with trials of pure vision or pure audition. These deficits were statistically reliable only for trials on which the modalities of the matching location switched from the penultimate to the final target in the sequence, indicating a switching cost. The switching cost for the pair in immediate succession means that the spatial images representing the target locations retain features of the visual or auditory representations from which they were derived. However, there was no reliable evidence of a performance cost for mixed modalities in the matching pair when the second of the two did not immediately follow the first, suggesting that more enduring spatial images in working memory may be amodal.

Two stage kickdown control system for a motor vehicle automatic transmission

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

Higashi, H.; Waki, K.; Fukuiri, M.

This patent describes a vehicle automatic transmission including a hydraulic torque converter and a transmission gear mechanism connected with the torque converter and having at least three gear stages of different gear ratios for forward drive. A principal feature of this system as described is a friction means for selecting one of the gear stages as well as a kickdown control means consisting of the first shift down circuit means for control of the friction means so that the transmission gear mechanism is shifted downward. A solenoid kick down means within the modality of the first shift down circuit andmore » a kick down switch means actuated by an engine control member when it is moved to a full power position provides control of the kick down solenoid and the effecting of a down shift. The shift down control means is composed of a second shift down circuit means for controlling the friction means so shift down occurs. The shift down solenoid contained in the second shift down circuit means in conjunction with a shift down switch actuated by engine control member movement to a position spaced a predetermined distance from the full power position control the shift down solenoid to effect a shift down. Thus this mechanism is actuated earlier than the kickdown switch means when the engine control member is moved toward the full power position. A time delay means from the time of actuation of the shift down switch means and controlling kickdown switch activation is also described.« less

Fault tolerant high-performance PACS network design and implementation

NASA Astrophysics Data System (ADS)

Chimiak, William J.; Boehme, Johannes M.

1998-07-01

The Wake Forest University School of Medicine and the Wake Forest University/Baptist Medical Center (WFUBMC) are implementing a second generation PACS. The first generation PACS provided helpful information about the functional and temporal requirements of the system. It highlighted the importance of image retrieval speed, system availability, RIS/HIS integration, the ability to rapidly view images on any PACS workstation, network bandwidth, equipment redundancy, and the ability for the system to evolve using standards-based components. This paper deals with the network design and implementation of the PACS. The physical layout of the hospital areas served by the PACS, the choice of network equipment and installation issues encountered are addressed. Efforts to optimize fault tolerance are discussed. The PACS network is a gigabit, mixed-media network based on LAN emulation over ATM (LANE) with a rapid migration from LANE to Multiple Protocols Over ATM (MPOA) planned. Two fault-tolerant backbone ATM switches serve to distribute network accesses with two load-balancing 622 megabit per second (Mbps) OC-12 interconnections. The switch was sized to be upgradable to provide a 2.54 Gbps OC-48 interconnection with an OC-12 interconnection as a load-balancing backup. Modalities connect with legacy network interface cards to a switched-ethernet device. This device has two 155 Mbps OC-3 load-balancing uplinks to each of the backbone ATM switches of the PACS. This provides a fault-tolerant logical connection to the modality servers which pass verified DICOM images to the PACS servers and proper PACS diagnostic workstations. Where fiber pulls were prohibitively expensive, edge ATM switches were installed with an OC-12 uplink to a backbone ATM switches. The PACS and data base servers are fault-tolerant, hot-swappable Sun Enterprise Servers with an OC-12 connection to a backbone ATM switch and a fast-ethernet connection to a back-up network. The workstations come with 10/100 BASET autosense cards. A redundant switched-ethernet network will be installed to provide yet another degree of network fault-tolerance. The switched-ethernet devices are connected to each of the backbone ATM switches with two-load-balancing OC-3 connections to provide fault-tolerant connectivity in the event of a primary network failure.

Multi-Modal Traveler Information System - Cellular 911-State of the Practice

DOT National Transportation Integrated Search

1997-05-19

Working paper evaluates the implemented public 911 and private non-911 cellular : based emergency centers around the country, and within the : Gary-Chicago-Milwaukee (GCM) Corridor and documents the impact, implications and : experiences of switching...

All-optical switching in silicon-on-insulator photonic wire nano-cavities.

PubMed

Belotti, Michele; Galli, Matteo; Gerace, Dario; Andreani, Lucio Claudio; Guizzetti, Giorgio; Md Zain, Ahmad R; Johnson, Nigel P; Sorel, Marc; De La Rue, Richard M

2010-01-18

We report on experimental demonstration of all-optical switching in a silicon-on-insulator photonic wire nanocavity operating at telecom wavelengths. The switching is performed with a control pulse energy as low as approximately 0.1 pJ on a cavity device that presents very high signal transmission, an ultra-high quality-factor, almost diffraction-limited modal volume and a footprint of only 5 microm(2). High-speed modulation of the cavity mode is achieved by means of optical injection of free carriers using a nanosecond pulsed laser. Experimental results are interpreted by means of finite-difference time-domain simulations. The possibility of using this device as a logic gate is also demonstrated.

Complete resolution of minocycline pigmentation following a single treatment with non-ablative 1550-nm fractional resurfacing in combination with the 755-nm Q-switched alexandrite laser.

PubMed

Vangipuram, Ramya K; DeLozier, Whitney L; Geddes, Elizabeth; Friedman, Paul M

2016-03-01

Pigmentation secondary to minocycline ingestion is an uncommon adverse event affecting 3.7-14.8% of treated individuals for which few effective therapies are available. Three patterns of minocycline pigmentation have a characteristic clinical and histological appearance. The pigment composition in each variety is different and occurs at varying skin depths. Accordingly, a tailored approach according to the type of minocycline pigmentation is crucial for treatment success. The purpose of this intervention was to evaluate the efficacy of non-ablative fractional photothermolysis in combination with the Q-switched alexandrite laser for the treatment of type I minocycline pigmentation on the face. A patient with type I minocycline pigmentation was treated with non-ablative 1550-nm fractional photothermolysis followed immediately by 755-nm Q-switched alexandrite laser and then observed clinically to determine the outcome of this modality. The patient was seen in clinic 1 month later following her single treatment session and 100% clearance of all blue facial pigment was observed. Non-ablative fractional photothermolysis in combination with the 755-nm Q-switched alexandrite laser should be considered for treatment of type I minocycline pigmentation. © 2015 Wiley Periodicals, Inc.

A biomimetic bioelectronic tongue: A switch for On- and Off- response of acid sensations.

PubMed

Zhang, Wei; Chen, Peihua; Zhou, Lianqun; Qin, Zhen; Gao, Keqiang; Yao, Jia; Li, Chuanyu; Wang, Ping

2017-06-15

The perception of sour taste in mammals is important for its basic modality properties and avoiding toxic substances. We explore a biomimetic bioelectronic tongue, which integrate MEA (microelectrode array) and taste receptor cell for acid detection as a switch. However, the acid-sensing mechanism and coding of the taste receptor cells in the periphery is not well understood, with long-standing debate. Therefore, we firstly construct a Hodgkin-Huxley type mathematical model of whole-cell acid-sensing taste receptor cells based on the electrophysiologic patch clamp recordings with different acid sensitive receptor expressing and different acidic stimulations. ASICs and PKDL channels are two most promising candidates for acidic sensation. ASICs channels contribute to the On response, and PKDL channels coding the Offset stimulations respectively, which function as a pair for switch. Therefore, with the advantage of effective and noninvasive detection for MEA, a sour taste biosensor based on MEA and taste receptor cells was designed and established to detect sour response from the elementary acid sensitive taste receptor cells during and after stimulus. From simulation and extracelluar potential recordings, we found the biomimetic bioelectronic tongue was acid-sensitive, as acid stimulation pH decrease, the firing frequency significantly increase. Furthermore, this reliable and effective MEA based bioelectronic tongue functioned as a switch for stimulation On and Off. This study provided a powerful platform to recognize sour stimulation and help elucidate the sour taste sensation and coding mechanism. Copyright © 2016 Elsevier B.V. All rights reserved.

Treatment of café-au-lait macules with a high-fluenced 1064-nm Q-switched neodymium:yttrium aluminum garnet laser.

PubMed

Kim, Jiehoon; Hur, Hoon; Kim, Yu Ri; Cho, Sung Bin

2018-02-01

Café-au-lait macules (CALMs) are light to dark brown macules or patches of increased melanin concentration found along the dermoepidermal junction. Although many attempts to treat CALMs using various kinds of laser/light-based devices have been reported, CALMs remain refractory thereto with high recurrence rates. In this case series, we describe four patients with idiopathic CALMs that were effectively and safely treated with a non-ablative, high-fluenced, Q-switched (QS), 1064-nm neodymium:yttrium aluminum garnet (Nd:YAG) laser. The typical laser parameters for treating CALMs, including a spot size of 7-7.5 mm, a fluence of 2.4-2.5 J/cm 2 , and one to two passes until the appearance of mild erythema, but not petechiae, were utilized in this study over 12-24 treatment sessions at 2-week intervals. We suggest that high-fluenced QS 1064-nm Nd:YAG laser treatment can be used as an effective and alternative treatment modality for CALMs with minimal risk of side effects.

Gaze-independent ERP-BCIs: augmenting performance through location-congruent bimodal stimuli

PubMed Central

Thurlings, Marieke E.; Brouwer, Anne-Marie; Van Erp, Jan B. F.; Werkhoven, Peter

2014-01-01

Gaze-independent event-related potential (ERP) based brain-computer interfaces (BCIs) yield relatively low BCI performance and traditionally employ unimodal stimuli. Bimodal ERP-BCIs may increase BCI performance due to multisensory integration or summation in the brain. An additional advantage of bimodal BCIs may be that the user can choose which modality or modalities to attend to. We studied bimodal, visual-tactile, gaze-independent BCIs and investigated whether or not ERP components’ tAUCs and subsequent classification accuracies are increased for (1) bimodal vs. unimodal stimuli; (2) location-congruent vs. location-incongruent bimodal stimuli; and (3) attending to both modalities vs. to either one modality. We observed an enhanced bimodal (compared to unimodal) P300 tAUC, which appeared to be positively affected by location-congruency (p = 0.056) and resulted in higher classification accuracies. Attending either to one or to both modalities of the bimodal location-congruent stimuli resulted in differences between ERP components, but not in classification performance. We conclude that location-congruent bimodal stimuli improve ERP-BCIs, and offer the user the possibility to switch the attended modality without losing performance. PMID:25249947

Alternative synthetic aperture radar (SAR) modalities using a 1D dynamic metasurface antenna

NASA Astrophysics Data System (ADS)

Boyarsky, Michael; Sleasman, Timothy; Pulido-Mancera, Laura; Imani, Mohammadreza F.; Reynolds, Matthew S.; Smith, David R.

2017-05-01

Synthetic aperture radar (SAR) systems conventionally rely on mechanically-actuated reflector dishes or large phased arrays for generating steerable directive beams. While these systems have yielded high-resolution images, the hardware suffers from considerable weight, high cost, substantial power consumption, and moving parts. Since these disadvantages are particularly relevant in airborne and spaceborne systems, a flat, lightweight, and low-cost solution is a sought-after goal. Dynamic metasurface antennas have emerged as a recent technology for generating waveforms with desired characteristics. Metasurface antennas consist of an electrically-large waveguide loaded with numerous subwavelength radiators which selectively leak energy from a guided wave into free space to form various radiation patterns. By tuning each radiating element, we can modulate the aperture's overall radiation pattern to generate steered directive beams, without moving parts or phase shifters. Furthermore, by using established manufacturing methods, these apertures can be made to be lightweight, low-cost, and planar, while maintaining high performance. In addition to their hardware benefits, dynamic metasurfaces can leverage their dexterity and high switching speeds to enable alternative SAR modalities for improved performance. In this work, we briefly discuss how dynamic metasurfaces can conduct existing SAR modalities with similar performance as conventional systems from a significantly simpler hardware platform. We will also describe two additional modalities which may achieve improved performance as compared to traditional modalities. These modalities, enhanced resolution stripmap and diverse pattern stripmap, offer the ability to circumvent the trade-off between resolution and region-of-interest size that exists within stripmap and spotlight. Imaging results with a simulated dynamic metasurface verify the benefits of these modalities and a discussion of implementation considerations and noise effects is also included. Ultimately, the hardware gains coupled with the additional modalities well-suited to dynamic metasurface antennas has poised them to propel the SAR field forward and open the door to exciting opportunities.

Active damping of spacecraft structural appendage vibrations

NASA Technical Reports Server (NTRS)

Fedor, Joseph V. (Inventor)

1990-01-01

An active vibration damper system, for bending in two orthogonal directions and torsion, in each of three mutually perpendicular axes is located at the extremities of the flexible appendages of a space platform. The system components for each axis includes: an accelerometer, filtering and signal processing apparatus, and a DC motor-inertia wheel torquer. The motor torquer, when driven by a voltage proportional to the relative vibration tip velocity, produces a reaction torque for opposing and therefore damping a specific modal velocity of vibration. The relative tip velocity is obtained by integrating the difference between the signal output from the accelerometer located at the end of the appendage with the output of a usually carried accelerometer located on a relatively rigid body portion of the space platform. A selector switch, with sequential stepping logic or highest modal vibration energy logic, steps to another modal tip velocity channel and receives a signal voltage to damp another vibration mode. In this manner, several vibration modes can be damped with a single sensor/actuator pair. When a three axis damper is located on each of the major appendages of the platform, then all of the system vibration modes can be effectively damped.

Imagining Writing Futures: Photography, Writing, and Technology

ERIC Educational Resources Information Center

McLean, Cheryl A.; Rowsell, Jennifer

2015-01-01

The article examines high school students' writing composition practices in multimodal instructional environments. We use Rosenblatt's transactional theory to look across the findings of 2 studies that blend traditional and digital modes of instruction in order to explore how modal switching can support students' reading and writing. We also…

Experience with PACS in an ATM/Ethernet switched network environment.

PubMed

Pelikan, E; Ganser, A; Kotter, E; Schrader, U; Timmermann, U

1998-03-01

Legacy local area network (LAN) technologies based on shared media concepts are not adequate for the growth of a large-scale picture archiving and communication system (PACS) in a client-server architecture. First, an asymmetric network load, due to the requests of a large number of PACS clients for only a few main servers, should be compensated by communication links to the servers with a higher bandwidth compared to the clients. Secondly, as the number of PACS nodes increases, the network throughout should not measurably cut production. These requirements can easily be fulfilled using switching technologies. Here asynchronous transfer mode (ATM) is clearly one of the hottest topics in networking because the ATM architecture provides integrated support for a variety of communication services, and it supports virtual networking. On the other hand, most of the imaging modalities are not yet ready for integration into a native ATM network. For a lot of nodes already joining an Ethernet, a cost-effective and pragmatic way to benefit from the switching concept would be a combined ATM/Ethernet switching environment. This incorporates an incremental migration strategy with the immediate benefits of high-speed, high-capacity ATM (for servers and high-sophisticated display workstations), while preserving elements of the existing network technologies. In addition, Ethernet switching instead of shared media Ethernet improves the performance considerably. The LAN emulation (LANE) specification by the ATM forum defines mechanisms that allow ATM networks to coexist with legacy systems using any data networking protocol. This paper points out the suitability of this network architecture in accordance with an appropriate system design.

An analysis toolbox to explore mesenchymal migration heterogeneity reveals adaptive switching between distinct modes

PubMed Central

Shafqat-Abbasi, Hamdah; Kowalewski, Jacob M; Kiss, Alexa; Gong, Xiaowei; Hernandez-Varas, Pablo; Berge, Ulrich; Jafari-Mamaghani, Mehrdad; Lock, John G; Strömblad, Staffan

2016-01-01

Mesenchymal (lamellipodial) migration is heterogeneous, although whether this reflects progressive variability or discrete, 'switchable' migration modalities, remains unclear. We present an analytical toolbox, based on quantitative single-cell imaging data, to interrogate this heterogeneity. Integrating supervised behavioral classification with multivariate analyses of cell motion, membrane dynamics, cell-matrix adhesion status and F-actin organization, this toolbox here enables the detection and characterization of two quantitatively distinct mesenchymal migration modes, termed 'Continuous' and 'Discontinuous'. Quantitative mode comparisons reveal differences in cell motion, spatiotemporal coordination of membrane protrusion/retraction, and how cells within each mode reorganize with changed cell speed. These modes thus represent distinctive migratory strategies. Additional analyses illuminate the macromolecular- and cellular-scale effects of molecular targeting (fibronectin, talin, ROCK), including 'adaptive switching' between Continuous (favored at high adhesion/full contraction) and Discontinuous (low adhesion/inhibited contraction) modes. Overall, this analytical toolbox now facilitates the exploration of both spontaneous and adaptive heterogeneity in mesenchymal migration. DOI: http://dx.doi.org/10.7554/eLife.11384.001 PMID:26821527

Q-switched Nd: YAG laser alone or with modified Jessner chemical peeling for treatment of mixed melasma in dark skin types: A comparative clinical, histopathological, and immunohistochemical study.

PubMed

Saleh, Fatma; Moftah, Noha H; Abdel-Azim, Eman; Gharieb, Marwa G

2017-10-22

Treatment of mixed melasma remains challenging. Promising results have been achieved with low-fluence 1064-nm Q-switched Nd-YAG laser; however, multiple sessions are necessary with occurrence of complications especially in dark skin types. So, combination methods may be recommended. To compare efficacy of Q-switched Nd-YAG laser alone or with modified Jessner's peel in mixed melasma in dark skin. Nineteen patients with mixed melasma received 6 sessions of laser on left side of face and alternating laser and modified Jessner on right side. Evaluation was carried out clinically through modified melasma area and severity index at 1 month after last session. Using histopathological, immunohistochemical, and computerized morphometric analysis, objective evaluation of melanin particle surface area and MART-1-positive cells was performed for pre- and post-treated skin biopsies. There was significant clinical improvement on both sides of face (P < .001), without significant difference (P > .05). At the sixth laser session on left side of face, ill-defined mottled hypopigmentation was observed in 21.05% of patients. Histopathologically, melanin particle surface area and number of MART-1-positive cells (total, epidermal, and dermal) were significantly decreased after two treatment modalities (P < .001), without significant difference in their reduction percentage between both sides of face (P > .05). Low-fluence Q-switched Nd-YAG laser alone and with modified Jessner's peel are equally effective regimens for mixed melasma clinically, histopathologically, and immunohistochemically. However, combined method is preferred, especially in dark skin, for obtaining better cosmetic result with fewer side effects of multiple laser sessions and decreasing cost rate of laser. © 2017 Wiley Periodicals, Inc.

Incidental category learning and cognitive load in a multisensory environment across childhood.

PubMed

Broadbent, H J; Osborne, T; Rea, M; Peng, A; Mareschal, D; Kirkham, N Z

2018-06-01

Multisensory information has been shown to facilitate learning (Bahrick & Lickliter, 2000; Broadbent, White, Mareschal, & Kirkham, 2017; Jordan & Baker, 2011; Shams & Seitz, 2008). However, although research has examined the modulating effect of unisensory and multisensory distractors on multisensory processing, the extent to which a concurrent unisensory or multisensory cognitive load task would interfere with or support multisensory learning remains unclear. This study examined the role of concurrent task modality on incidental category learning in 6- to 10-year-olds. Participants were engaged in a multisensory learning task while also performing either a unisensory (visual or auditory only) or multisensory (audiovisual) concurrent task (CT). We found that engaging in an auditory CT led to poorer performance on incidental category learning compared with an audiovisual or visual CT, across groups. In 6-year-olds, category test performance was at chance in the auditory-only CT condition, suggesting auditory concurrent tasks may interfere with learning in younger children, but the addition of visual information may serve to focus attention. These findings provide novel insight into the use of multisensory concurrent information on incidental learning. Implications for the deployment of multisensory learning tasks within education across development and developmental changes in modality dominance and ability to switch flexibly across modalities are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Treatment of pigmentary disorders in patients with skin of color with a novel 755 nm picosecond, Q-switched ruby, and Q-switched Nd:YAG nanosecond lasers: A retrospective photographic review.

PubMed

Levin, Melissa Kanchanapoomi; Ng, Elise; Bae, Yoon-Soo Cindy; Brauer, Jeremy A; Geronemus, Roy G

2016-02-01

Laser procedures in skin of color (SOC) patients are challenging due to the increased risk of dyspigmentation and scarring. A novel 755 nm alexandrite picosecond laser has demonstrated effectiveness for tattoo removal and treatment of acne scars. No studies to date have evaluated its applications in pigmentary disorders. The purpose of this retrospective study was to evaluate the safety profile and efficacy of the picosecond alexandrite laser compared to the current standard treatment, Q-switched ruby and neodynium (Nd):YAG nanosecond lasers, for pigmentary disorders in SOC patients. A retrospective photographic and chart evaluation of seventy 755 nm alexandrite picosecond, ninety-two Q-switched frequency doubled 532 nm and 1,064 nm Nd:YAG nanosecond, and forty-seven Q-switched 694 nm ruby nanosecond laser treatments, in forty-two subjects of Fitzpatrick skin types III-VI was conducted in a single laser specialty center. The picosecond laser was a research prototype device. Treatment efficacy was assessed by two blinded physician evaluators, using a visual analog scale for percentage of pigmentary clearance in standard photographs. Subject assessment of efficacy, satisfaction, and adverse events was performed using a questionnaire survey. The most common pigmentary disorder treated was Nevus of Ota (38.1%), followed by solar lentigines (23.8%). Other pigmentary disorders included post-inflammatory hyperpigmentation, congenital nevus, café au lait macule, dermal melanocytosis, Nevus of Ito, and Becker's nevus. Clinical efficacy of the Q-switched nanosecond lasers and picosecond laser treatments were comparable for lesions treated on the face with a mean visual analog score of 2.57 and 2.44, respectively, corresponding to approximately 50% pigmentary clearance. Subject questionnaires were completed in 58.8% of the picosecond subjects and 52.0% of the Q-switched subjects. Eighty four percent of subjects receiving Q-switched nanosecond laser treatments and 50% of the subjects receiving alexandrite 755 nm picosecond laser treatments felt satisfied to completely satisfied. Side effects observed in subjects treated with the alexandrite 755 nm picosecond laser were similar to those commonly observed and reported with the nanosecond Q-switched technology. All side effects were temporary, resolving within one month, and no long-term complications were noted. All patients who were very satisfied with their picosecond laser treatment for Nevus of Ota noted a delayed improvement only after 3 months. The 755 nm alexandrite picosecond, 694 nm ruby, 532 nm, and 1064 nm neodynium:YAG nanosecond lasers appear to be safe and effective modalities for removal of pigmentary disorders in skin of color patients with no long-term complications if used appropriately. This study demonstrates the potential of the 755 nm alexandrite picosecond laser in further clinical applications beyond tattoo removal. While the Q-switched lasers were effective, promising results were also observed using an early version of the novel picosecond laser for the removal of pigmentary lesions in SOC patients. As we continue to improve our understanding of the 755 nm picosecond laser, this device may prove to be a safe and effective alternative to the Q-switched lasers for the treatment of facial pigmented lesions in patients with skin of color. © 2016 Wiley Periodicals, Inc.

Adherence to Positive Airway Therapy After Switching From CPAP to ASV: A Big Data Analysis.

PubMed

Pépin, Jean-Louis D; Woehrle, Holger; Liu, Dongquan; Shao, Shiyun; Armitstead, Jeff P; Cistulli, Peter A; Benjafield, Adam V; Malhotra, Atul

2018-01-15

There is a lack of data regarding adherence trajectories when switching from continuous positive airway pressure (CPAP) to adaptive servoventilation (ASV) in the context of persistent or treatment-emergent central sleep apnea (CSA). This study investigated 90-day adherence rates in patients with sleep apnea based on the type of positive airway pressure (PAP) device used and any switching of PAP modality over time. Telemonitoring data were obtained from a United States PAP database. Eligible patients were a 30% random sample who started PAP, plus all who started ASV, from January 1, 2015 to October 2, 2015. All received PAP and had at least one session with usage of 1 hour or more. Adherence and device usage were determined in three groups: started on CPAP and stayed on CPAP (CPAP only); started on ASV and stayed on ASV (ASV only); started on CPAP, switched to ASV (Switch). The United States Medicare definition of adherence was used. The study included 198,890 patients; 189,724 (CPAP only), 8,957 (ASV only) and 209 (Switch). In the Switch group, average apnea-hypopnea index decreased significantly on ASV versus CPAP. At 90 days, adherence rates were 73.8% and 73.2% in the CPAP only and ASV only groups. In the Switch group, CPAP adherence was 62.7%, improving to 76.6% after the switch to ASV. Mean device usage at 90 days was 5.27, 5.31, and 5.73 h/d in the CPAP only, ASV only, and Switch groups, respectively. Treatment-emergent or persistent CSA during CPAP reduced therapy adherence, but adherence improved early after switching from CPAP to ASV. © 2018 American Academy of Sleep Medicine

Dynamic switching enables efficient bacterial colonization in flow.

PubMed

Kannan, Anerudh; Yang, Zhenbin; Kim, Minyoung Kevin; Stone, Howard A; Siryaporn, Albert

2018-05-22

Bacteria colonize environments that contain networks of moving fluids, including digestive pathways, blood vasculature in animals, and the xylem and phloem networks in plants. In these flow networks, bacteria form distinct biofilm structures that have an important role in pathogenesis. The physical mechanisms that determine the spatial organization of bacteria in flow are not understood. Here, we show that the bacterium P. aeruginosa colonizes flow networks using a cyclical process that consists of surface attachment, upstream movement, detachment, movement with the bulk flow, and surface reattachment. This process, which we have termed dynamic switching, distributes bacterial subpopulations upstream and downstream in flow through two phases: movement on surfaces and cellular movement via the bulk. The model equations that describe dynamic switching are identical to those that describe dynamic instability, a process that enables microtubules in eukaryotic cells to search space efficiently to capture chromosomes. Our results show that dynamic switching enables bacteria to explore flow networks efficiently, which maximizes dispersal and colonization and establishes the organizational structure of biofilms. A number of eukaryotic and mammalian cells also exhibit movement in two phases in flow, which suggests that dynamic switching is a modality that enables efficient dispersal for a broad range of cell types.

Combined EEG-fNIRS decoding of motor attempt and imagery for brain switch control: an offline study in patients with tetraplegia.

PubMed

Blokland, Yvonne; Spyrou, Loukianos; Thijssen, Dick; Eijsvogels, Thijs; Colier, Willy; Floor-Westerdijk, Marianne; Vlek, Rutger; Bruhn, Jorgen; Farquhar, Jason

2014-03-01

Combining electrophysiological and hemodynamic features is a novel approach for improving current performance of brain switches based on sensorimotor rhythms (SMR). This study was conducted with a dual purpose: to test the feasibility of using a combined electroencephalogram/functional near-infrared spectroscopy (EEG-fNIRS) SMR-based brain switch in patients with tetraplegia, and to examine the performance difference between motor imagery and motor attempt for this user group. A general improvement was found when using both EEG and fNIRS features for classification as compared to using the single-modality EEG classifier, with average classification rates of 79% for attempted movement and 70% for imagined movement. For the control group, rates of 87% and 79% were obtained, respectively, where the "attempted movement" condition was replaced with "actual movement." A combined EEG-fNIRS system might be especially beneficial for users who lack sufficient control of current EEG-based brain switches. The average classification performance in the patient group for attempted movement was significantly higher than for imagined movement using the EEG-only as well as the combined classifier, arguing for the case of a paradigm shift in current brain switch research.

Regime dependence of photo-darkening-induced modal degradation in high power fiber amplifier (Conference Presentation)

NASA Astrophysics Data System (ADS)

Boullet, Johan; Vincont, Cyril; Jolly, Alain; Pierre, Christophe

2017-03-01

Thermally induced transverse modal instabilities (TMI) have attracted these five years an intense research efforts of the entire fiber laser development community, as it represents the current most limiting effect of further power scaling of high power fiber laser. Anyway, since 2014, a few publications point out a new limiting thermal effect: fiber modal degradation (FMD). It is characterized by a power rollover and simultaneous increase of the cladding light at an average power far from the TMI threshold together with a degraded beam which does not exhibit temporal fluctuations, which is one of the main characteristic of TMI. We report here on the first systemic experimental study of FMD in a high power photonic crystal fiber. We put a particular emphasis on the dependence of its average power threshold on the regime of operation. We experimentally demonstrate that this dependence is intrinsically linked to regime-dependent PD-saturated losses, which are nearly three times higher in CW regime than in short pulse picosecond regime. We make the hypothesis that the existence of these different PD equilibrium states between CW regime and picosecond QCW pulsed regime is due to a partial photo-bleaching of color centers in picosecond regime thanks to a higher probability of multi-photon process induced photobleaching (PB) at high peak power. This hypothesis is corroborated by the demonstration of the reversibility of the FMD induced in CW regime by simply switching the seed CW 1064 nm light by a short pulse, picosecond oscillator.

E-bike trials’ potential to promote sustained changes in car owners mobility habits

NASA Astrophysics Data System (ADS)

Moser, Corinne; Blumer, Yann; Lena Hille, Stefanie

2018-04-01

Modal shifts hold considerable potential to mitigate carbon emissions. Electric bikes (e-bikes) represent a promising energy- and carbon-efficient alternative to cars. However, as mobility behaviour is highly habitual, convincing people to switch from cars to e-bikes is challenging. One strategy to accomplish this is the disruption of existing habits—a key idea behind an annual e-bike promotion programme in Switzerland, in which car owners can try out an e-bike for free over a two-week period in exchange for their car keys. By means of a longitudinal survey, we measured the long-term effects of this trial on mobility-related habitual associations. After one year, participants’ habitual association with car use had weakened significantly. This finding was valid both for participants who bought an e-bike after the trial and those who did not. Our findings contrast the results of other studies who find that the effect of interventions to induce modal shifts wears off over time. We conclude that an e-bike trial has the potential to break mobility habits and motivate car owners to use more sustainable means of transport.

Necroptosis: a potential, promising target and switch in acute pancreatitis.

PubMed

Wang, Gang; Qu, Feng-Zhi; Li, Le; Lv, Jia-Chen; Sun, Bei

2016-02-01

Pancreatic acinar cell death is the major pathophysiological change in early acute pancreatitis (AP), and the death modalities are important factors determining its progression and prognosis. During AP, acinar cells undergo two major modes of death, including necrosis and apoptosis. Acinar necrosis can lead to intensely local and systemic inflammatory responses, which both induce and aggravate the lesion. Necrosis has long been considered an unregulated, and passive cell death process. Since the effective interventions of necrosis are difficult to perform, its relevant studies have not received adequate attention. Necroptosis is a newly discovered cell death modality characterized by both necrosis and apoptosis, i.e., it is actively regulated by special genes, while has the typical morphological features of necrosis. Currently, necroptosis is gradually becoming an important topic in the fields of inflammatory diseases. The preliminary results from necroptosis in AP have confirmed the existence of acinar cell necroptosis, which may be a potential target for effectively regulating inflammatory injuries and improving its outcomes; however, the functional changes and mechanisms of necroptosis still require further investigation. This article reviewed the progress of necroptosis in AP to provide a reference for deeply understanding the pathogenic mechanisms of AP and identifying new therapeutic targets.

Tuning the mind: Exploring the connections between musical ability and executive functions.

PubMed

Slevc, L Robert; Davey, Nicholas S; Buschkuehl, Martin; Jaeggi, Susanne M

2016-07-01

A growing body of research suggests that musical experience and ability are related to a variety of cognitive abilities, including executive functioning (EF). However, it is not yet clear if these relationships are limited to specific components of EF, limited to auditory tasks, or reflect very general cognitive advantages. This study investigated the existence and generality of the relationship between musical ability and EFs by evaluating the musical experience and ability of a large group of participants and investigating whether this predicts individual differences on three different components of EF - inhibition, updating, and switching - in both auditory and visual modalities. Musical ability predicted better performance on both auditory and visual updating tasks, even when controlling for a variety of potential confounds (age, handedness, bilingualism, and socio-economic status). However, musical ability was not clearly related to inhibitory control and was unrelated to switching performance. These data thus show that cognitive advantages associated with musical ability are not limited to auditory processes, but are limited to specific aspects of EF. This supports a process-specific (but modality-general) relationship between musical ability and non-musical aspects of cognition. Copyright © 2016 Elsevier B.V. All rights reserved.

Speech-in-speech perception and executive function involvement

PubMed Central

Perrone-Bertolotti, Marcela; Tassin, Maxime

2017-01-01

This present study investigated the link between speech-in-speech perception capacities and four executive function components: response suppression, inhibitory control, switching and working memory. We constructed a cross-modal semantic priming paradigm using a written target word and a spoken prime word, implemented in one of two concurrent auditory sentences (cocktail party situation). The prime and target were semantically related or unrelated. Participants had to perform a lexical decision task on visual target words and simultaneously listen to only one of two pronounced sentences. The attention of the participant was manipulated: The prime was in the pronounced sentence listened to by the participant or in the ignored one. In addition, we evaluate the executive function abilities of participants (switching cost, inhibitory-control cost and response-suppression cost) and their working memory span. Correlation analyses were performed between the executive and priming measurements. Our results showed a significant interaction effect between attention and semantic priming. We observed a significant priming effect in the attended but not in the ignored condition. Only priming effects obtained in the ignored condition were significantly correlated with some of the executive measurements. However, no correlation between priming effects and working memory capacity was found. Overall, these results confirm, first, the role of attention for semantic priming effect and, second, the implication of executive functions in speech-in-noise understanding capacities. PMID:28708830

Emergence of ion channel modal gating from independent subunit kinetics.

PubMed

Bicknell, Brendan A; Goodhill, Geoffrey J

2016-09-06

Many ion channels exhibit a slow stochastic switching between distinct modes of gating activity. This feature of channel behavior has pronounced implications for the dynamics of ionic currents and the signaling pathways that they regulate. A canonical example is the inositol 1,4,5-trisphosphate receptor (IP3R) channel, whose regulation of intracellular Ca(2+) concentration is essential for numerous cellular processes. However, the underlying biophysical mechanisms that give rise to modal gating in this and most other channels remain unknown. Although ion channels are composed of protein subunits, previous mathematical models of modal gating are coarse grained at the level of whole-channel states, limiting further dialogue between theory and experiment. Here we propose an origin for modal gating, by modeling the kinetics of ligand binding and conformational change in the IP3R at the subunit level. We find good agreement with experimental data over a wide range of ligand concentrations, accounting for equilibrium channel properties, transient responses to changing ligand conditions, and modal gating statistics. We show how this can be understood within a simple analytical framework and confirm our results with stochastic simulations. The model assumes that channel subunits are independent, demonstrating that cooperative binding or concerted conformational changes are not required for modal gating. Moreover, the model embodies a generally applicable principle: If a timescale separation exists in the kinetics of individual subunits, then modal gating can arise as an emergent property of channel behavior.

Influence of switches and crossings on wheel profile evolution in freight vehicles

NASA Astrophysics Data System (ADS)

Casanueva, Carlos; Doulgerakis, Emmanouil; Jönsson, Per-Anders; Stichel, Sebastian

2014-05-01

Wheel reprofiling costs for freight vehicles are a major issue in Sweden, reducing the profitability of freight traffic operations and therefore hindering the modal shift needed for achieving reduced emissions. In order to understand the damage modes in freight vehicles, uniform wear prediction with Archard's wear law has been studied in a two-axle timber transport wagon, and simulation results have been compared to measurements. Challenges of wheel wear prediction in freight wagons are discussed, including the influence of block brakes and switches and crossings. The latter have a major influence on the profile evolution of this case study, so specific simulations are performed and a thorough discussion is carried out.

The impact of transfer from hemodialysis on peritoneal dialysis technique survival.

PubMed

Nessim, Sharon J; Bargman, Joanne M; Jassal, S Vanita; Oliver, Matthew J; Na, Yingbo; Perl, Jeffrey

2015-01-01

A significant proportion of peritoneal dialysis (PD) patients receive an initial period of hemodialysis (HD) before transitioning to PD ("PD-switch"). We sought to better understand the risks of PD technique failure (TF) and mortality for those patients compared with patients starting with PD as their first dialysis modality ("PD-first"). Using Canadian Organ Replacement Register data, we compared the risk of PD TF between PD-first and PD-switch patients within the first year after HD initiation. In a secondary analysis, the PD-switch patients were stratified into three groups based on timing of the switch from initial HD to PD as follows: 0 - 90 days, 91 - 180 days, and 181 - 365 days. Each group was compared with PD-first patients for risk of PD TF and death. Between 2001 and 2010, 9404 patients initiated PD as their first renal replacement therapy, and 3757 switched from HD to PD. After multivariable adjustment, the risk of PD TF was higher among PD-switch patients than among PD-first patients [adjusted hazard ratio (AHR): 1.37; 95% confidence interval (CI): 1.26 to 1.49], particularly within the first year after the switch from HD to PD (AHR: 1.51; 95% CI: 1.36 to 1.68). There was no association between time on HD within the first year and subsequent risk of PD TF. For all the stratified PD-switch groups, death rates were higher than those for PD-first patients. Compared with patients who start renal replacement therapy with PD, those who transfer from HD to PD within the first year on dialysis experience higher rates of PD TF and death, with the highest risk being observed in the initial year after the switch to PD. Copyright © 2015 International Society for Peritoneal Dialysis.

Dynamic characteristics of the blisk with synchronized switch damping based on negative capacitor

NASA Astrophysics Data System (ADS)

Liu, J.; Li, L.; Huang, X.; Jezequel, L.

2017-10-01

In this paper, we propose a method to suppress the vibration of the integral bladed disk ('blisk' for short) in aero-engines using synchronized switch damping based on negative capacitor (SSDNC). Different from the classical piezoelectric shunt damping, SSDNC is a type of nonlinear piezoelectric damping. A multi-harmonic balance method combined with the alternating frequency/time method (MHBM-AFT) is used to predict and further analyze the dynamic characteristics of the electromechanical system, and an arc-length continuation technique is used to improve the convergence of the method. In order to validate the algorithm as well as to recognize the characteristics of the system with SSDNC, a two degree-of-freedom (2-DOF) system with SSDNC is studied at first. The nonlinear complex modal information is calculated and compared with those of the corresponding system with a linear RL shunt circuit. The results indicate that the natural frequencies and modal damping ratio do not change with the modal amplitude, which means that SSDNC has the same modal damping corresponding to different system energy levels. In addition, SSDNC can improve the damping level of all the modes nearly without affecting the natural frequencies of the system. Then, the forced response of the blisk with SSDNC in the frequency domain is calculated and analyzed, including a tuned blisk, which is excited by the traveling wave excitation with a single harmonic and multi-harmonic, and a mistuned blisk, which is excited by traveling wave excitation with a single harmonic and multi-harmonic. We present two advantages of the SSDNC technique when compared with piezoelectric shunt damping. First, SSDNC can suppress the vibration of the blisk under a multi-harmonic wideband the traveling wave, and second, the vibration suppression performance of SSDNC is insensitive to the mistuning of mechanical parameters of the blisk. The results will be of great significance in overcoming the problem of the amplitude magnification induced by the inevitable mistuning of the blisk in aero-engines.

Oculomotor Cognitive Control Abnormalities in Australian Rules Football Players with a History of Concussion.

PubMed

Clough, Meaghan; Mutimer, Steven; Wright, David K; Tsang, Adrian; Costello, Daniel M; Gardner, Andrew J; Stanwell, Peter; Mychasiuk, Richelle; Sun, Mujun; Brady, Rhys D; McDonald, Stuart J; Webster, Kyria M; Johnstone, Maddison R; Semple, Bridgette D; Agoston, Denes V; White, Owen B; Frayne, Richard; Fielding, Joanne; O'Brien, Terence J; Shultz, Sandy R

2018-03-01

This study used oculomotor, cognitive, and multi-modal magnetic resonance imaging (MRI) measures to assess for neurological abnormalities in current asymptomatic amateur Australian rules footballers (i.e., Australia's most participated collision sport) with a history of sports-related concussion (SRC). Participants were 15 male amateur Australian rules football players with a history of SRC greater than 6 months previously, and 15 sex-, age-, and education-matched athlete control subjects that had no history of neurotrauma or participation in collision sports. Participants completed a clinical interview, neuropsychological measures, and oculomotor measures of cognitive control. MRI investigation involved structural imaging, as well as diffusion tensor imaging and resting-state functional MRI sequences. Despite no group differences on conventional neuropsychological tests and multi-modal MRI measures, Australian rules football players with a history of SRC performed significantly worse on an oculomotor switch task: a measure of cognitive control that interleaves the response of looking towards a target (i.e., a prosaccade) with the response of looking away from a target (i.e., an antisaccade). Specifically, Australian footballers performed significantly shorter latency prosaccades and found changing from an antisaccade trial to a prosaccade trial (switch cost) significantly more difficult than control subjects. Poorer switch cost was related to poorer performance on a number of neuropsychological measures of inhibitory control. Further, when comparing performance on the cognitively more demanding switch task with performance on simpler, antisaccade/prosaccades tasks which require a single response, Australian footballers demonstrated a susceptibility to increased cognitive load, compared to the control group who were unaffected. These initial results suggest that current asymptomatic amateur Australian rules football players with a history of SRC may have persisting, subtle, cognitive changes, which are demonstrable on oculomotor cognitive measures. Future studies are required in order to further elucidate the full nature and clinical relevance of these findings.

Low-threshold mechanoreceptors play a frequency-dependent dual role in subjective ratings of mechanical allodynia.

PubMed

Löken, Line S; Duff, Eugene P; Tracey, Irene

2017-12-01

In the setting of injury, myelinated primary afferent fibers that normally signal light touch are thought to switch modality and instead signal pain. In the absence of injury, touch is perceived as more intense when firing rates of Aβ afferents increase. However, it is not known if varying the firing rates of Aβ afferents have any consequence to the perception of dynamic mechanical allodynia (DMA). We hypothesized that, in the setting of injury, the unpleasantness of DMA would be intensified as the firing rates of Aβ afferents increase. Using a stimulus-response protocol established in normal skin, where an increase in brush velocity results in an increase of Aβ afferent firing rates, we tested if brush velocity modulated the unpleasantness of capsaicin-induced DMA. We analyzed how changes in estimated low-threshold mechanoreceptor firing activity influenced perception and brain activity (functional MRI) of DMA. Brushing on normal skin was perceived as pleasant, but brushing on sensitized skin produced both painful and pleasant sensations. Surprisingly, there was an inverse relationship between Aβ firing rates and unpleasantness such that brush stimuli that produced low firing rates were most painful and those that elicited high firing rates were rated as pleasant. Concurrently to this, we found increased cortical activity in response to low Aβ firing rates in regions previously implicated in pain processing during brushing of sensitized skin, but not normal skin. We suggest that Aβ signals do not merely switch modality to signal pain during injury. Instead, they exert a high- and low-frequency-dependent dual role in the injured state, with respectively both pleasant and unpleasant consequences. NEW & NOTEWORTHY We suggest that Aβ signals do not simply switch modality to signal pain during injury but play a frequency-dependent and dual role in the injured state with both pleasant and unpleasant consequences. These results provide a framework to resolve the apparent paradox of how touch can inhibit pain, as proposed by the Gate Control Theory and the existence of dynamic mechanical allodynia.

Transfer of classical eyeblink conditioning with electrical stimulation of mPFC or tone as conditioned stimulus in guinea pigs.

PubMed

Yao, Juan; Wu, Guang-Yan; Liu, Guo-Long; Liu, Shu-Lei; Yang, Yi; Wu, Bing; Li, Xuan; Feng, Hua; Sui, Jian-Feng

2014-11-01

Learning with a stimulus from one sensory modality can facilitate subsequent learning with a new stimulus from a different sensory modality. To date, the characteristics and mechanism of this phenomenon named transfer effect still remain ambiguous. Our previous work showed that electrical stimulation of medial prefrontal cortex (mPFC) as a conditioned stimulus (CS) could successfully establish classical eyeblink conditioning (EBC). The present study aimed to (1) observe whether transfer of EBC learning would occur when CSs shift between central (mPFC electrical stimulation as a CS, mPFC-CS) and peripheral (tone as a CS, tone CS); (2) compare the difference in transfer effect between the two paradigms, delay EBC (DEBC) and trace EBC (TEBC). A total of 8 groups of guinea pigs were tested in the study, including 4 experimental groups and 4 control groups. Firstly, the experimental groups accepted central (or peripheral) CS paired with corneal airpuff unconditioned stimulus (US); then, CS shifted to the peripheral (or central) and paired with US. The control groups accepted corresponding central (or peripheral) CS and pseudo-paired with US, and then shifted CS from central (or peripheral) to peripheral (or central) and paired with US. The results showed that the acquisition rates of EBC were higher in experimental groups than in control groups after CS switching from central to peripheral or vice versa, and the CR acquisition rate was remarkably higher in DEBC than in TEBC in both transfer ways. The results indicate that EBC transfer can occur between learning established with mPFC-CS and tone CS. Memory of CS-US association for delay paradigm was less disturbed by the sudden switch of CS than for trace paradigm. This study provides new insight into neural mechanisms underlying conditioned reflex as well as the role of mPFC. Copyright © 2014 Elsevier B.V. All rights reserved.

Reward maximization justifies the transition from sensory selection at childhood to sensory integration at adulthood.

PubMed

Daee, Pedram; Mirian, Maryam S; Ahmadabadi, Majid Nili

2014-01-01

In a multisensory task, human adults integrate information from different sensory modalities--behaviorally in an optimal Bayesian fashion--while children mostly rely on a single sensor modality for decision making. The reason behind this change of behavior over age and the process behind learning the required statistics for optimal integration are still unclear and have not been justified by the conventional Bayesian modeling. We propose an interactive multisensory learning framework without making any prior assumptions about the sensory models. In this framework, learning in every modality and in their joint space is done in parallel using a single-step reinforcement learning method. A simple statistical test on confidence intervals on the mean of reward distributions is used to select the most informative source of information among the individual modalities and the joint space. Analyses of the method and the simulation results on a multimodal localization task show that the learning system autonomously starts with sensory selection and gradually switches to sensory integration. This is because, relying more on modalities--i.e. selection--at early learning steps (childhood) is more rewarding than favoring decisions learned in the joint space since, smaller state-space in modalities results in faster learning in every individual modality. In contrast, after gaining sufficient experiences (adulthood), the quality of learning in the joint space matures while learning in modalities suffers from insufficient accuracy due to perceptual aliasing. It results in tighter confidence interval for the joint space and consequently causes a smooth shift from selection to integration. It suggests that sensory selection and integration are emergent behavior and both are outputs of a single reward maximization process; i.e. the transition is not a preprogrammed phenomenon.

Switchable multi-wavelength fiber laser based on modal interference

NASA Astrophysics Data System (ADS)

Ma, Lin; Jiang, Sun; Qi, Yan-Hui; Kang, Ze-Xin; Jian, Shui-Sheng

2015-08-01

A comb fiber filter based on modal interference is proposed and demonstrated in this paper. Here two cascaded up-tapers are used to excite the cladding mode, and a core-offset jointing point is used to act as an interference component. Experimental results show that this kind of structure possesses a comb filter property in a range of the C-band. The measured extinction ratio is better than 12 dB with an insertion loss of about 11 dB. A switchable multi-wavelength erbium-doped fiber laser based on this novel comb filter is demonstrated. By adjusting the polarization controller, the output laser can be switched among single-, dual-, and three-wavelengths with a side mode suppression ratio of better than 45 dB.

Origin of the OFF state variability in ReRAM cells

NASA Astrophysics Data System (ADS)

Salaoru, Iulia; Khiat, Ali; Li, Qingjiang; Berdan, Radu; Papavassiliou, Christos; Prodromakis, Themistoklis

2014-04-01

This work exploits the switching dynamics of nanoscale resistive random access memory (ReRAM) cells with particular emphasis on the origin of the observed variability when cells are consecutively cycled/programmed at distinct memory states. It is demonstrated that this variance is a common feature of all ReRAM elements and is ascribed to the formation and rupture of conductive filaments that expand across the active core, independently of the material employed as the active switching core, the causal physical switching mechanism, the switching mode (bipolar/unipolar) or even the unit cells' dimensions. Our hypothesis is supported through both experimental and theoretical studies on TiO2 and In2O3 : SnO2 (ITO) based ReRAM cells programmed at three distinct resistive states. Our prototypes employed TiO2 or ITO active cores over 5 × 5 µm2 and 100 × 100 µm2 cell areas, with all tested devices demonstrating both unipolar and bipolar switching modalities. In the case of TiO2-based cells, the underlying switching mechanism is based on the non-uniform displacement of ionic species that foster the formation of conductive filaments. On the other hand, the resistive switching observed in the ITO-based devices is considered to be due to a phase change mechanism. The selected experimental parameters allowed us to demonstrate that the observed programming variance is a common feature of all ReRAM devices, proving that its origin is dependent upon randomly oriented local disorders within the active core that have a substantial impact on the overall state variance, particularly for high-resistive states.

The Feasibility and Acceptability of Using Technology-Based Daily Diaries with HIV-Infected Young Men Who have Sex with Men: A Comparison of Internet and Voice Modalities.

PubMed

Cherenack, Emily M; Wilson, Patrick A; Kreuzman, Andrew M; Price, Georgine N

2016-08-01

This study delivered a daily diary to 67 HIV-infected men who have sex with men (MSM) between 16 and 24 years old for 66 days to measure HIV-risk behaviors and other psychosocial variables via two diary modalities: internet (accessible via any web-enabled device) and voice (accessible via telephone). Participants were randomized to complete one diary modality for 33 days before switching to the second modality for 33 days. The study was implemented in three urban HIV health care centers in the United States where participants were receiving services. Through diary data and qualitative interview data, we examined the feasibility and acceptability of the dairies and identified barriers and facilitators of dairy compliance. Results show high participant retention in the daily diary (93.4 %) and high compliance for the number of dairies completed (72.4 %). Internet diaries were preferred by 92 % of participants and completed at a significantly higher rate (77.5 %) than voice diaries (67.7 %). Facilitators included opportunities for self-reflection and cathartic sharing, monetary compensation, relationships with study staff, and daily reminders. Barriers included being busy or not having privacy at the time of reminders, forgetting, and falling asleep. Participants also described barriers and facilitators unique to each modality. Overall, both modalities were feasible and acceptable for use with our sample of HIV-infected MSM.

The Feasibility and Acceptability of Using Technology-Based Daily Diaries with HIV-Infected Young Men who have Sex with Men: A Comparison of Internet and Voice Modalities

PubMed Central

Cherenack, Emily M.; Wilson, Patrick A.; Kreuzman, Andrew M.; Price, Georgine N.

2016-01-01

This study delivered a daily diary to 67 HIV-infected men who have sex with men (MSM) between 16 and 24 years old for 66 days to measure HIV-risk behaviors and other psychosocial variables via two diary modalities: internet (accessible via any web-enabled device) and voice (accessible via telephone). Participants were randomized to complete one diary modality for 33 days before switching to the second modality for 33 days. The study was implemented in three urban HIV health care centers in the United States where participants were receiving services. Through diary data and qualitative interview data, we examined the feasibility and acceptability of the dairies and identified barriers and facilitators of dairy compliance. Results show high participant retention in the daily diary (93.4%) and high compliance for the number of dairies completed (72.4%). Internet diaries were preferred by 92% of participants and completed at a significantly higher rate (77.5%) than voice diaries (67.7%). Facilitators included opportunities for self-reflection and cathartic sharing, monetary compensation, relationships with study staff, and daily reminders. Barriers included being busy or not having privacy at the time of reminders, forgetting, and falling asleep. Participants also described barriers and facilitators unique to each modality. Overall, both modalities were feasible and acceptable for use with our sample of HIV-infected MSM. PMID:26837629

Implementation of a Learning Assistant Program Improves Student Performance on Higher-Order Assessments

PubMed Central

Sellami, Nadia; Shaked, Shanna; Laski, Frank A.; Eagan, Kevin M.; Sanders, Erin R.

2017-01-01

Learning assistant (LA) programs have been implemented at a range of institutions, usually as part of a comprehensive curricular transformation accompanied by a pedagogical switch to active learning. While this shift in pedagogy has led to increased student learning gains, the positive effect of LAs has not yet been distinguished from that of active learning. To determine the effect that LAs would have beyond a student-centered instructional modality that integrated active learning, we introduced an LA program into a large-enrollment introductory molecular biology course that had already undergone a pedagogical transformation to a highly structured, flipped (HSF) format. We used questions from a concept test (CT) and exams to compare student performance in LA-supported HSF courses with student performance in courses without LAs. Students in the LA-supported course did perform better on exam questions common to both HSF course modalities but not on the CT. In particular, LA-supported students’ scores were higher on common exam questions requiring higher-order cognitive skills, which LAs were trained to foster. Additionally, underrepresented minority (URM) students particularly benefited from LA implementation. These findings suggest that LAs may provide additional learning benefits to students beyond the use of active learning, especially for URM students. PMID:29167224

Antidepressant-Induced Female Sexual Dysfunction.

PubMed

Lorenz, Tierney; Rullo, Jordan; Faubion, Stephanie

2016-09-01

Because 1 in 6 women in the United States takes antidepressants and a substantial proportion of patients report some disturbance of sexual function while taking these medications, it is a near certainty that the practicing clinician will need to know how to assess and manage antidepressant-related female sexual dysfunction. Adverse sexual effects can be complex because there are several potentially overlapping etiologies, including sexual dysfunction associated with the underlying mood disorder. As such, careful assessment of sexual function at the premedication visit followed by monitoring at subsequent visits is critical. Treatment of adverse sexual effects can be pharmacological (dose reduction, drug discontinuation or switching, augmentation, or using medications with lower adverse effect profiles), behavioral (exercising before sexual activity, scheduling sexual activity, vibratory stimulation, psychotherapy), complementary and integrative (acupuncture, nutraceuticals), or some combination of these modalities. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Medial prefrontal serotonin in the rat is involved in goal-directed behaviour when affect guides decision making.

PubMed

van der Plasse, Geoffrey; La Fors, Sabrina S B M; Meerkerk, Dorie T J; Joosten, Ruud N J M A; Uylings, Harry B M; Feenstra, Matthijs G P

2007-12-01

Across species, serotonin (5-HT) depletion in the prefrontal cortex (PFC) has been shown to cause impaired performance on tests of cognitive flexibility and the processing of affective information (e.g. information with an 'emotional' content). While recent work has explored the specific role of the orbital PFC herein, the role of the medial PFC remains unclear. The aim of our current experiments was to study the role of medial PFC 5-HT in both the processing of affective information and reversal learning across stimulus modalities. To this end, we selectively destroyed 5-HT terminals in the medial PFC of male Wistar rats by means of local infusion of the toxin 5,7-dihydroxytryptamine. Both control and lesioned animals were tested in two reversal learning paradigms with either spatial or odour cues and an affective switch from non-preferred to preferred food rewards. Our results indicate that a pellet switch during reversal learning impaired performance in control animals but not in lesioned animals, independent of the stimulus modality. These results indicate that lesioned animals are not guided in their behaviour by the affective value of the reward like intact animals and thus that medial prefrontal 5-HT is needed for affective processing in goal-directed behaviour.

On the bistable zone of milling processes

PubMed Central

Dombovari, Zoltan; Stepan, Gabor

2015-01-01

A modal-based model of milling machine tools subjected to time-periodic nonlinear cutting forces is introduced. The model describes the phenomenon of bistability for certain cutting parameters. In engineering, these parameter domains are referred to as unsafe zones, where steady-state milling may switch to chatter for certain perturbations. In mathematical terms, these are the parameter domains where the periodic solution of the corresponding nonlinear, time-periodic delay differential equation is linearly stable, but its domain of attraction is limited due to the existence of an unstable quasi-periodic solution emerging from a secondary Hopf bifurcation. A semi-numerical method is presented to identify the borders of these bistable zones by tracking the motion of the milling tool edges as they might leave the surface of the workpiece during the cutting operation. This requires the tracking of unstable quasi-periodic solutions and the checking of their grazing to a time-periodic switching surface in the infinite-dimensional phase space. As the parameters of the linear structural behaviour of the tool/machine tool system can be obtained by means of standard modal testing, the developed numerical algorithm provides efficient support for the design of milling processes with quick estimates of those parameter domains where chatter can still appear in spite of setting the parameters into linearly stable domains. PMID:26303918

A low-fluence 1064-nm Q-switched neodymium-doped yttrium aluminium garnet laser for the treatment of café-au-lait macules.

PubMed

Kim, Hyeong-Rae; Ha, Jeong-Min; Park, Min-Soo; Lee, Young; Seo, Young-Joon; Kim, Chang-Deok; Lee, Jeung-Hoon; Im, Myung

2015-09-01

Café-au-lait macules (CALMs) are a common pigmentary disorder. Although a variety of laser modalities have been used to treat CALMs, their efficacies vary and dyspigmentation may develop. We evaluated the clinical efficacy and safety of a low-fluence 1064-nm Q-switched neodymium-doped yttrium aluminium garnet (Nd:YAG) laser for the treatment of CALMs. In a preliminary investigation, 6 patients underwent a split-lesion comparative study with 532- and 1064-nm Q-switched Nd:YAG laser treatment. In total, 32 patients with 39 CALMs were enrolled in a subsequent prospective trial to evaluate the treatment with a low-fluence 1064-nm Q-switched Nd:YAG laser. In the preliminary study, the 1064-nm treatment group had a more favorable response and a shorter recovery time. In a subsequent prospective trial of a 1064-nm laser, 74.4% of the lesions showed a clinical response with clearance of ≥50.0%. The treatment regimen was well tolerated; 15.4% of patients experienced adverse events. The study participants were followed for 6 months, and there were no relevant treatment controls in the prospective trial group. Low-fluence 1064-nm Q-switched Nd:YAG laser therapy afforded good clinical improvement for treating CALMs. Copyright © 2015 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Fractional 532-nm Q-switched Nd:YAG laser: One of the safest novel treatment modality to treat café-au-lait macules.

PubMed

Won, Kwang Hee; Lee, Ye Jin; Rhee, Do Young; Chang, Sung Eun

2016-10-01

Café-au-lait macules (CALMs) are benign epidermal basilar hyperpigmentations that can be found in an isolated form or in association with neurocutaneous syndromes. Frequency-doubled Q-switched neodymium-doped yttrium aluminum garnet laser (532-nm QSNYL) does not penetrate deeply into the skin and is therefore suitable for epidermal pigmented lesion. Fractional photothermolysis (FP) targets only very small areas of the skin, without injuring adjacent areas of healthy, normal skin. Herein, we report a case of CALMs successfully treated with fractional 532-nm QSNYL. By applying FP to 532-nm QSNYL, we could treat CALMs safely with less downtime as compared to conventional laser treatments and expect more energy delivery for each microscopic hole, thereby allowing higher response rate.

Concentration: The Neural Underpinnings of How Cognitive Load Shields Against Distraction.

PubMed

Sörqvist, Patrik; Dahlström, Örjan; Karlsson, Thomas; Rönnberg, Jerker

2016-01-01

Whether cognitive load-and other aspects of task difficulty-increases or decreases distractibility is subject of much debate in contemporary psychology. One camp argues that cognitive load usurps executive resources, which otherwise could be used for attentional control, and therefore cognitive load increases distraction. The other camp argues that cognitive load demands high levels of concentration (focal-task engagement), which suppresses peripheral processing and therefore decreases distraction. In this article, we employed an functional magnetic resonance imaging (fMRI) protocol to explore whether higher cognitive load in a visually-presented task suppresses task-irrelevant auditory processing in cortical and subcortical areas. The results show that selectively attending to an auditory stimulus facilitates its neural processing in the auditory cortex, and switching the locus-of-attention to the visual modality decreases the neural response in the auditory cortex. When the cognitive load of the task presented in the visual modality increases, the neural response to the auditory stimulus is further suppressed, along with increased activity in networks related to effortful attention. Taken together, the results suggest that higher cognitive load decreases peripheral processing of task-irrelevant information-which decreases distractibility-as a side effect of the increased activity in a focused-attention network.

Concentration: The Neural Underpinnings of How Cognitive Load Shields Against Distraction

PubMed Central

Sörqvist, Patrik; Dahlström, Örjan; Karlsson, Thomas; Rönnberg, Jerker

2016-01-01

Whether cognitive load—and other aspects of task difficulty—increases or decreases distractibility is subject of much debate in contemporary psychology. One camp argues that cognitive load usurps executive resources, which otherwise could be used for attentional control, and therefore cognitive load increases distraction. The other camp argues that cognitive load demands high levels of concentration (focal-task engagement), which suppresses peripheral processing and therefore decreases distraction. In this article, we employed an functional magnetic resonance imaging (fMRI) protocol to explore whether higher cognitive load in a visually-presented task suppresses task-irrelevant auditory processing in cortical and subcortical areas. The results show that selectively attending to an auditory stimulus facilitates its neural processing in the auditory cortex, and switching the locus-of-attention to the visual modality decreases the neural response in the auditory cortex. When the cognitive load of the task presented in the visual modality increases, the neural response to the auditory stimulus is further suppressed, along with increased activity in networks related to effortful attention. Taken together, the results suggest that higher cognitive load decreases peripheral processing of task-irrelevant information—which decreases distractibility—as a side effect of the increased activity in a focused-attention network. PMID:27242485

Bilingual processing of ASL-English code-blends: The consequences of accessing two lexical representations simultaneously

PubMed Central

Emmorey, Karen; Petrich, Jennifer; Gollan, Tamar H.

2012-01-01

Bilinguals who are fluent in American Sign Language (ASL) and English often produce code-blends - simultaneously articulating a sign and a word while conversing with other ASL-English bilinguals. To investigate the cognitive mechanisms underlying code-blend processing, we compared picture-naming times (Experiment 1) and semantic categorization times (Experiment 2) for code-blends versus ASL signs and English words produced alone. In production, code-blending did not slow lexical retrieval for ASL and actually facilitated access to low-frequency signs. However, code-blending delayed speech production because bimodal bilinguals synchronized English and ASL lexical onsets. In comprehension, code-blending speeded access to both languages. Bimodal bilinguals’ ability to produce code-blends without any cost to ASL implies that the language system either has (or can develop) a mechanism for switching off competition to allow simultaneous production of close competitors. Code-blend facilitation effects during comprehension likely reflect cross-linguistic (and cross-modal) integration at the phonological and/or semantic levels. The absence of any consistent processing costs for code-blending illustrates a surprising limitation on dual-task costs and may explain why bimodal bilinguals code-blend more often than they code-switch. PMID:22773886

Modal kinematics for multisection continuum arms.

PubMed

Godage, Isuru S; Medrano-Cerda, Gustavo A; Branson, David T; Guglielmino, Emanuele; Caldwell, Darwin G

2015-05-13

This paper presents a novel spatial kinematic model for multisection continuum arms based on mode shape functions (MSF). Modal methods have been used in many disciplines from finite element methods to structural analysis to approximate complex and nonlinear parametric variations with simple mathematical functions. Given certain constraints and required accuracy, this helps to simplify complex phenomena with numerically efficient implementations leading to fast computations. A successful application of the modal approximation techniques to develop a new modal kinematic model for general variable length multisection continuum arms is discussed. The proposed method solves the limitations associated with previous models and introduces a new approach for readily deriving exact, singularity-free and unique MSF's that simplifies the approach and avoids mode switching. The model is able to simulate spatial bending as well as straight arm motions (i.e., pure elongation/contraction), and introduces inverse position and orientation kinematics for multisection continuum arms. A kinematic decoupling feature, splitting position and orientation inverse kinematics is introduced. This type of decoupling has not been presented for these types of robotic arms before. The model also carefully accounts for physical constraints in the joint space to provide enhanced insight into practical mechanics and impose actuator mechanical limitations onto the kinematics thus generating fully realizable results. The proposed method is easily applicable to a broad spectrum of continuum arm designs.

Comparative study of 2-DOF micromirrors for precision light manipulation

NASA Astrophysics Data System (ADS)

Young, Johanna I.; Shkel, Andrei M.

2001-08-01

Many industry experts predict that the future of fiber optic telecommunications depends on the development of all-optical components for switching of photonic signals from fiber to fiber throughout the networks. MEMS is a promising technology for providing all-optical switching at high speeds with significant cost reductions. This paper reports on the the analysis of two designs for 2-DOF electrostatically actuated MEMS micromirrors for precision controllable large optical switching arrays. The behavior of the micromirror designs is predicted by coupled-field electrostatic and modal analysis using a finite element analysis (FEA) multi-physics modeling software. The analysis indicates that the commonly used gimbal type mirror design experiences electrostatic interference and would therefore be difficult to precisely control for 2-DOF motion. We propose a new design approach which preserves 2-DOF actuation while minimizing electrostatic interference between the drive electrodes and the mirror. Instead of using two torsional axes, we use one actuator which combines torsional and flexural DOFs. A comparative analysis of the conventional gimbal design and the one proposed in this paper is performed.

Task-Related Suppression of the Brainstem Frequency following Response

DTIC Science & Technology

2013-02-18

from switching between attention-demanding task stimuli. However, it is also possible that the opposite may be true – the addition of a task, instead...of a resting, passive state may suppress the FFR. Here we examined the influence of a subsequent task, and the relevance of the task modality, on...as a baseline consisting of the same background stimuli in the absence of a task. FFR pitch strength and amplitude of the primary frequency response

Medial prefrontal serotonin in the rat is involved in goal-directed behaviour when affect guides decision making

PubMed Central

La Fors, Sabrina S. B. M.; Meerkerk, Dorie T. J.; Joosten, Ruud N. J. M. A.; Uylings, Harry B. M.; Feenstra, Matthijs G. P.

2007-01-01

Rationale Across species, serotonin (5-HT) depletion in the prefrontal cortex (PFC) has been shown to cause impaired performance on tests of cognitive flexibility and the processing of affective information (e.g. information with an ‘emotional’ content). While recent work has explored the specific role of the orbital PFC herein, the role of the medial PFC remains unclear. Objectives The aim of our current experiments was to study the role of medial PFC 5-HT in both the processing of affective information and reversal learning across stimulus modalities. Materials and methods To this end, we selectively destroyed 5-HT terminals in the medial PFC of male Wistar rats by means of local infusion of the toxin 5,7-dihydroxytryptamine. Both control and lesioned animals were tested in two reversal learning paradigms with either spatial or odour cues and an affective switch from non-preferred to preferred food rewards. Results Our results indicate that a pellet switch during reversal learning impaired performance in control animals but not in lesioned animals, independent of the stimulus modality. Conclusion These results indicate that lesioned animals are not guided in their behaviour by the affective value of the reward like intact animals and thus that medial prefrontal 5-HT is needed for affective processing in goal-directed behaviour. PMID:17874235

A chimeric switch-receptor targeting PD1 augments the efficacy of second generation CAR T-Cells in advanced solid tumors

PubMed Central

Liu, Xiaojun; Ranganathan, Raghuveer; Jiang, Shuguang; Fang, Chongyun; Sun, Jing; Kim, Soyeon; Newick, Kheng; Lo, Albert; June, Carl H.; Zhao, Yangbing; Moon, Edmund K.

2015-01-01

Chimeric antigen receptor (CAR)-modified adoptive T-cell therapy (ATC) has been successfully applied to the treatment of hematologic malignancies, but faces many challenges in solid tumors. One major obstacle is the immune-suppressive effects induced in both naturally-occurring and genetically-modified tumor infiltrating lymphocytes (TILs) by inhibitory receptors (IRs), namely PD1. We hypothesized that interfering with PD1 signaling would augment CAR T cell activity against solid tumors. To address this possibility, we introduced a genetically-engineered switch receptor construct, comprising the truncated extracellular domain of PD1 and the transmembrane and cytoplasmic signaling domains of CD28, into CAR T-cells. We tested the effect of this supplement, “PD1CD28”, on human CAR T-cells targeting aggressive models of human solid tumors expressing relevant tumor antigens. Treatment of mice bearing large, established solid tumors with PD1CD28 CAR T-cells led to significant regression in tumor volume due to enhanced CAR TIL infiltrate, decreased susceptibility to tumor-induced hypofunction, and attenuation of IR expression compared to treatments with CAR T-cells alone or PD1 antibodies. Taken together, our findings suggest that the application of PD1CD28 to boost CAR T-cell activity is efficacious against solid tumors via a variety of mechanisms, prompting clinical investigation of this potentially promising treatment modality. PMID:26979791

Task-specific reorganization of the auditory cortex in deaf humans

PubMed Central

Bola, Łukasz; Zimmermann, Maria; Mostowski, Piotr; Jednoróg, Katarzyna; Marchewka, Artur; Rutkowski, Paweł; Szwed, Marcin

2017-01-01

The principles that guide large-scale cortical reorganization remain unclear. In the blind, several visual regions preserve their task specificity; ventral visual areas, for example, become engaged in auditory and tactile object-recognition tasks. It remains open whether task-specific reorganization is unique to the visual cortex or, alternatively, whether this kind of plasticity is a general principle applying to other cortical areas. Auditory areas can become recruited for visual and tactile input in the deaf. Although nonhuman data suggest that this reorganization might be task specific, human evidence has been lacking. Here we enrolled 15 deaf and 15 hearing adults into an functional MRI experiment during which they discriminated between temporally complex sequences of stimuli (rhythms). Both deaf and hearing subjects performed the task visually, in the central visual field. In addition, hearing subjects performed the same task in the auditory modality. We found that the visual task robustly activated the auditory cortex in deaf subjects, peaking in the posterior–lateral part of high-level auditory areas. This activation pattern was strikingly similar to the pattern found in hearing subjects performing the auditory version of the task. Although performing the visual task in deaf subjects induced an increase in functional connectivity between the auditory cortex and the dorsal visual cortex, no such effect was found in hearing subjects. We conclude that in deaf humans the high-level auditory cortex switches its input modality from sound to vision but preserves its task-specific activation pattern independent of input modality. Task-specific reorganization thus might be a general principle that guides cortical plasticity in the brain. PMID:28069964

Task-specific reorganization of the auditory cortex in deaf humans.

PubMed

Bola, Łukasz; Zimmermann, Maria; Mostowski, Piotr; Jednoróg, Katarzyna; Marchewka, Artur; Rutkowski, Paweł; Szwed, Marcin

2017-01-24

The principles that guide large-scale cortical reorganization remain unclear. In the blind, several visual regions preserve their task specificity; ventral visual areas, for example, become engaged in auditory and tactile object-recognition tasks. It remains open whether task-specific reorganization is unique to the visual cortex or, alternatively, whether this kind of plasticity is a general principle applying to other cortical areas. Auditory areas can become recruited for visual and tactile input in the deaf. Although nonhuman data suggest that this reorganization might be task specific, human evidence has been lacking. Here we enrolled 15 deaf and 15 hearing adults into an functional MRI experiment during which they discriminated between temporally complex sequences of stimuli (rhythms). Both deaf and hearing subjects performed the task visually, in the central visual field. In addition, hearing subjects performed the same task in the auditory modality. We found that the visual task robustly activated the auditory cortex in deaf subjects, peaking in the posterior-lateral part of high-level auditory areas. This activation pattern was strikingly similar to the pattern found in hearing subjects performing the auditory version of the task. Although performing the visual task in deaf subjects induced an increase in functional connectivity between the auditory cortex and the dorsal visual cortex, no such effect was found in hearing subjects. We conclude that in deaf humans the high-level auditory cortex switches its input modality from sound to vision but preserves its task-specific activation pattern independent of input modality. Task-specific reorganization thus might be a general principle that guides cortical plasticity in the brain.

Ongoing In Vivo Immunoglobulin Class Switch DNA Recombination in Chronic Lymphocytic Leukemia B Cells1

PubMed Central

Cerutti, Andrea; Zan, Hong; Kim, Edmund C.; Shah, Shefali; Schattner, Elaine J.; Schaffer, András; Casali, Paolo

2015-01-01

Chronic lymphocytic leukemia (CLL) results from the expansion of malignant CD5+ B cells that usually express IgD and IgM. These leukemic cells can give rise in vivo to clonally related IgG+ or IgA+ elements. The requirements and modalities of this process remain elusive. Here we show that leukemic B cells from 14 of 20 CLLs contain the hallmarks of ongoing Ig class switch DNA recombination (CSR), including extrachromosomal switch circular DNAs and circle transcripts generated by direct Sμ→Sγ, Sμ→Sα, and Sμ→Sε as well as sequential Sγ→Sα and Sγ→Sε CSR. Similar CLL B cells express transcripts for activation-induced cytidine deaminase, a critical component of the CSR machinery, and contain germline IH-CH and mature VHDJH-CH transcripts encoded by multiple Cγ, Cα, and Cε genes. Ongoing CSR occurs in only a fraction of the CLL clone, as only small proportions of CD5+CD19+ cells express surface IgG or IgA and lack IgM and IgD. In vivo class-switching CLL B cells down-regulate switch circles and circle transcripts in vitro unless exposed to exogenous CD40 ligand and IL-4. In addition, CLL B cells that do not class switch in vivo activate the CSR machinery and secrete IgG, IgA, or IgE upon in vitro exposure to CD40 ligand and IL-4. These findings indicate that in CLL at least some members of the malignant clone actively differentiate in vivo along a pathway that induces CSR. They also suggest that this process is elicited by external stimuli, including CD40 ligand and IL-4, provided by bystander immune cells. PMID:12444172

Cardiology-oriented PACS

NASA Astrophysics Data System (ADS)

Silva, Augusto F. d.; Costa, Carlos; Abrantes, Pedro; Gama, Vasco; Den Boer, Ad

1998-07-01

This paper describes an integrated system designed to provide efficient means for DICOM compliant cardiac imaging archival, transmission and visualization based on a communications backbone matching recent enabling telematic technologies like Asynchronous Transfer Mode (ATM) and switched Local Area Networks (LANs). Within a distributed client-server framework, the system was conceived on a modality based bottom-up approach, aiming ultrafast access to short term archives and seamless retrieval of cardiac video sequences throughout review stations located at the outpatient referral rooms, intensive and intermediate care units and operating theaters.

Laser-generated shockwave for clearing medical device biofilms.

PubMed

Kizhner, Victor; Krespi, Yosef P; Hall-Stoodley, Luanne; Stoodley, Paul

2011-04-01

This study aimed to evaluate a laser method of biofilm interruption from the surface of various common medical devices and from surgically removed sinus tissue with adherent biofilms in a timely manner. Biofilm has emerged as a new threat not amenable to most antibiotic treatments. Biofilms, as opposed to planktonic bacteria, develop an extracellular polymeric slime matrix to facilitate adherence to host tissue or a prosthetic surface and to form a protective shield. A laser-induced biofilms disruption concept was previously described. Biofilms were grown in the laboratory on metallic and plastic medical device surfaces such as stents. Attempts to remove the biofilms with a laser were undertaken three times for each device. Q-switched Nd:YAG laser-generated shockwaves affecting Pseudomonas aeruginosa biofilms expressing yellow fluorescent protein (YFP) biofilm coating were applied with biologically safe parameters utilizing a fiber delivery system and a special probe. A confocal microscope was used to identify the biofilm structure prior to, during, and after laser application. The amount of biofilm removed from the medical devices in time was measured by quantifying green fluorescence. The biofilm fluctuated and eventually broke off the surface as shock waves neared the target. The time to remove 97.9 ± 0.4% (mean ± 1SD, n = 3) the biofilm from the surface of a Nitinol (NiTi) stent ranged from 4 to 10 s. The detached biofilm was observed floating in fluid media in various microscopic size particles. A new treatment modality using laser-generated shockwaves in the warfare against biofilms growing on surgical devices was demonstrated. Q-switched laser pulses stripped biofilm from the surface it adhered to, changing the bacteria to their planktonic form, making them amenable to conventional treatment. This therapeutic modality appears to be rapid, effective, and safe on metallic and plastic medical device surfaces.

a Method for Preview Vibration Control of Systems Having Forcing Inputs and Rapidly-Switched Dampers

NASA Astrophysics Data System (ADS)

ElBeheiry, E. M.

1998-07-01

In a variety of applications, especially in large scale dynamic systems, the mechanization of different vibration control elements in different locations would be decided by limitations placed on the modal vibration of the system and the inherent dynamic coupling between its modes. Also, the quality of vibration control to the economy of producing the whole system would be another trade-off leading to a mix of passive, active and semi-active vibration control elements in one system. This termactiveis limited to externally powered vibration control inputs and the termsemi-activeis limited to rapidly switched dampers. In this article, an optimal preview control method is developed for application to dynamic systems having active and semi-active vibration control elements mechanized at different locations in one system. The system is then a piecewise (bilinear) controller in which two independent sets of control inputs appear additively and multiplicatively. Calculus of variations along with the Hamiltonian approach are employed for the derivation of this method. In essence, it requires the active elements to be ideal force generators and the switched dampers to have the property of on-line variation of the damping characteristics to pre-determined limits. As the dampers switch during operation the whole system's structure differs, and then values of the active forcing inputs are adapted to match these rapid changes. Strictly speaking, each rapidly switched damper has pre-known upper and lower damping levels and it can take on any in-between value. This in-between value is to be determined by the method as long as the damper tracks a pre-known fully active control demand. In every damping state of each semi-active damper the method provides the optimal matching values of the active forcing inputs. The method is shown to have the feature of solving simple standard matrix equations to obtain closed form solutions. A comprehensive 9-DOF tractor semi-trailer model is used to demonstrate the effectiveness of the method. Time domain predictions are made to compare performance of ride and tyre-to-road contact in the model for the presented method with those of some other active and semi-active suspension designs.

Public antibodies to malaria antigens generated by two LAIR1 insertion modalities.

PubMed

Pieper, Kathrin; Tan, Joshua; Piccoli, Luca; Foglierini, Mathilde; Barbieri, Sonia; Chen, Yiwei; Silacci-Fregni, Chiara; Wolf, Tobias; Jarrossay, David; Anderle, Marica; Abdi, Abdirahman; Ndungu, Francis M; Doumbo, Ogobara K; Traore, Boubacar; Tran, Tuan M; Jongo, Said; Zenklusen, Isabelle; Crompton, Peter D; Daubenberger, Claudia; Bull, Peter C; Sallusto, Federica; Lanzavecchia, Antonio

2017-08-31

In two previously described donors, the extracellular domain of LAIR1, a collagen-binding inhibitory receptor encoded on chromosome 19 (ref. 1), was inserted between the V and DJ segments of an antibody. This insertion generated, through somatic mutations, broadly reactive antibodies against RIFINs, a type of variant antigen expressed on the surface of Plasmodium falciparum-infected erythrocytes. To investigate how frequently such antibodies are produced in response to malaria infection, we screened plasma from two large cohorts of individuals living in malaria-endemic regions. Here we report that 5-10% of malaria-exposed individuals, but none of the European blood donors tested, have high levels of LAIR1-containing antibodies that dominate the response to infected erythrocytes without conferring enhanced protection against febrile malaria. By analysing the antibody-producing B cell clones at the protein, cDNA and gDNA levels, we characterized additional LAIR1 insertions between the V and DJ segments and discovered a second insertion modality whereby the LAIR1 exon encoding the extracellular domain and flanking intronic sequences are inserted into the switch region. By exon shuffling, this mechanism leads to the production of bispecific antibodies in which the LAIR1 domain is precisely positioned at the elbow between the VH and CH1 domains. Additionally, in one donor the genomic DNA encoding the VH and CH1 domains was deleted, leading to the production of a camel-like LAIR1-containing antibody. Sequencing of the switch regions of memory B cells from European blood donors revealed frequent templated inserts originating from transcribed genes that, in rare cases, comprised exons with orientations and frames compatible with expression. These results reveal different modalities of LAIR1 insertion that lead to public and dominant antibodies against infected erythrocytes and suggest that insertion of templated DNA represents an additional mechanism of antibody diversification that can be selected in the immune response against pathogens and exploited for B cell engineering.

Gaze and Feet as Additional Input Modalities for Interacting with Geospatial Interfaces

NASA Astrophysics Data System (ADS)

Çöltekin, A.; Hempel, J.; Brychtova, A.; Giannopoulos, I.; Stellmach, S.; Dachselt, R.

2016-06-01

Geographic Information Systems (GIS) are complex software environments and we often work with multiple tasks and multiple displays when we work with GIS. However, user input is still limited to mouse and keyboard in most workplace settings. In this project, we demonstrate how the use of gaze and feet as additional input modalities can overcome time-consuming and annoying mode switches between frequently performed tasks. In an iterative design process, we developed gaze- and foot-based methods for zooming and panning of map visualizations. We first collected appropriate gestures in a preliminary user study with a small group of experts, and designed two interaction concepts based on their input. After the implementation, we evaluated the two concepts comparatively in another user study to identify strengths and shortcomings in both. We found that continuous foot input combined with implicit gaze input is promising for supportive tasks.

Brain activations during bimodal dual tasks depend on the nature and combination of component tasks

PubMed Central

Salo, Emma; Rinne, Teemu; Salonen, Oili; Alho, Kimmo

2015-01-01

We used functional magnetic resonance imaging to investigate brain activations during nine different dual tasks in which the participants were required to simultaneously attend to concurrent streams of spoken syllables and written letters. They performed a phonological, spatial or “simple” (speaker-gender or font-shade) discrimination task within each modality. We expected to find activations associated specifically with dual tasking especially in the frontal and parietal cortices. However, no brain areas showed systematic dual task enhancements common for all dual tasks. Further analysis revealed that dual tasks including component tasks that were according to Baddeley's model “modality atypical,” that is, the auditory spatial task or the visual phonological task, were not associated with enhanced frontal activity. In contrast, for other dual tasks, activity specifically associated with dual tasking was found in the left or bilateral frontal cortices. Enhanced activation in parietal areas, however, appeared not to be specifically associated with dual tasking per se, but rather with intermodal attention switching. We also expected effects of dual tasking in left frontal supramodal phonological processing areas when both component tasks required phonological processing and in right parietal supramodal spatial processing areas when both tasks required spatial processing. However, no such effects were found during these dual tasks compared with their component tasks performed separately. Taken together, the current results indicate that activations during dual tasks depend in a complex manner on specific demands of component tasks. PMID:25767443

Proposal of ultra-compact NAND/NOR/XNOR all-optical logic gates based on a nonlinear 3x1 multimode interference

NASA Astrophysics Data System (ADS)

Tajaldini, Mehdi; Mat Jafri, M. Z.

2014-05-01

We present a highly miniaturized multimode interference (MMI) coupler based on nonlinear modal propagation analysis (NMPA) method as a novel design method and potential application for optical NAND, NOR and XNOR logic gates for Boolean logic signal processing devices. Crystalline polydiacetylene is used to allow the appearances of nonlinear effects in low input intensities and ultra- short length to control the MMI coupler as an active device to access light switching due to its high nonlinear susceptibility. We consider a 10x33 μm2 MMI structure with three inputs and one output. Notably, the access facets are single-mode waveguides with sub-micron width. The center input contributes to control the induced light propagation in MMI by intensity variation whereas others could be launched by particular intensity when they are ON and 0 in OFF. Output intensity is analyzed in various sets of inputs to show the capability of Boolean logic gates, the contrast between ON and OFF is calculated on mentioned gates to present the efficiency. Good operation in low intensity and highly miniaturized MMI coupler is observed. Furthermore, nonlinear effects could be realized through the modal interferences. The issue of high insertion loss is addressed with a 3×3 upgraded coupler. Furthermore, the main significant aspect of this paper is simulating an MMI coupler that is launched by three nonlinear inputs, simultaneously, whereas last presents have never studied more than one input in nonlinear regimes.

A clinical comparison between a new dual-chamber pacing mode-AAIsafeR and DDD mode.

PubMed

Xue-Jun, Ren; Zhihong, Han; Ye, Wang; Huifeng, Du; Jinrong, Zhang; Fang, Chen; Jihong, Guo

2010-02-01

The aim of this study was to compare the cross-follow-up results in DDD or AAISafeR mode and to describe the safety and effectiveness of this pacing mode. The Symphony 2450/2550 cardiac pacemakers were implanted in 30 patients with sick sinus syndrome between February 2006 and September 2006. They were randomized to the DDD mode or AAISafeR mode for 3 months and then crossed over to the alternate pacing modality for an additional 3 months. No AAISafeR-related adverse event was observed. All documented episodes of paroxysmal atrial ventricular block caused the immediate switch of the pacing mode from AAI to DDD. The cumulative percent ventricular pacing was significantly reduced in the AAISafeR mode compared with the DDD mode (0.9% [0%-3%] versus 51.3% [2%-91%] P = 0.001; 2.94% [0%-18%] versus 41.18% [0%-65%] P = 0.0001). After 3 months in DDD mode, left atrial diameter, left ventricular enddiastolic diameter, and left ventricular end-systolic diameter increased significantly and left ventricular ejection fraction decreased. However, no obvious changes appeared in 3 months of AAISafeR mode. Switches to DDD occurred during follow-up in 21 patients due to different-degree atrial ventricular block. The AAISafeR mode substantially reduces the amount of unnecessary right ventricular pacing in the bradycardia population and effectively prevents the deleterious effects on cardiac performance. An international randomized study will further ascertain the efficacy of this new pacing mode specifically in the prevention of heart failure hospitalization and atrial fibrillation.

Clinical experience with the use of rhG-CSF in secondary autoimmune neutropenia.

PubMed

Smith, M A; Smith, J G

2002-04-01

This paper outlines the impact of granulocyte-colony stimulating factor (G-CSF) used as a single modality therapy in 17 patients with secondary autoimmune neutropenia (S-AIN) who had been treated a multiple number of times previously. Fifteen of these patients had demonstrable antineutrophil antibodies and two had cellular S-AIN with haemopoietic inhibitory T-cells present in the marrow. Prior to treatment, all had had problems with infection. All patients responded within 7 days of commencement of treatment. Provided G-CSF neutrophil counts were maintained above 1 x 109/l, no further infections occurred. This was achievable by using G-CSF administered as infrequently as once every 8 days. Eight of the 17 patients remained on G-CSF, although five switched to the glycosylated form because of side-effects. None have developed osteoporosis despite 47.29 patient years of total experience with G-CSF. In conclusion both glycosylated and nonglycosylated G-CSF can be used effectively in treating AIN on a long-term basis.

Enhanced audio-visual interactions in the auditory cortex of elderly cochlear-implant users.

PubMed

Schierholz, Irina; Finke, Mareike; Schulte, Svenja; Hauthal, Nadine; Kantzke, Christoph; Rach, Stefan; Büchner, Andreas; Dengler, Reinhard; Sandmann, Pascale

2015-10-01

Auditory deprivation and the restoration of hearing via a cochlear implant (CI) can induce functional plasticity in auditory cortical areas. How these plastic changes affect the ability to integrate combined auditory (A) and visual (V) information is not yet well understood. In the present study, we used electroencephalography (EEG) to examine whether age, temporary deafness and altered sensory experience with a CI can affect audio-visual (AV) interactions in post-lingually deafened CI users. Young and elderly CI users and age-matched NH listeners performed a speeded response task on basic auditory, visual and audio-visual stimuli. Regarding the behavioral results, a redundant signals effect, that is, faster response times to cross-modal (AV) than to both of the two modality-specific stimuli (A, V), was revealed for all groups of participants. Moreover, in all four groups, we found evidence for audio-visual integration. Regarding event-related responses (ERPs), we observed a more pronounced visual modulation of the cortical auditory response at N1 latency (approximately 100 ms after stimulus onset) in the elderly CI users when compared with young CI users and elderly NH listeners. Thus, elderly CI users showed enhanced audio-visual binding which may be a consequence of compensatory strategies developed due to temporary deafness and/or degraded sensory input after implantation. These results indicate that the combination of aging, sensory deprivation and CI facilitates the coupling between the auditory and the visual modality. We suggest that this enhancement in multisensory interactions could be used to optimize auditory rehabilitation, especially in elderly CI users, by the application of strong audio-visually based rehabilitation strategies after implant switch-on. Copyright © 2015 Elsevier B.V. All rights reserved.

Time Course of Peritoneal Function in Automated and Continuous Peritoneal Dialysis

PubMed Central

Michels, Wieneke M.; Verduijn, Marion; Parikova, Alena; Boeschoten, Elisabeth W.; Struijk, Dirk G.; Dekker, Friedo W.; Krediet, Raymond T.

2012-01-01

♦ Background and Objectives: In automated peritoneal dialysis (APD), a patient’s peritoneal membrane is more intensively exposed to fresh dialysate than it is in continuous ambulatory peritoneal dialysis (CAPD). Our aim was to study, in incident peritoneal dialysis (PD) patients, the influence of APD—compared with that of CAPD—on peritoneal transport over 4 years. ♦ Design, Setting, Participants, and Measurements: Patients were included if at least 2 annual standard permeability analyses (SPAs) performed with 3.86% glucose were available while the patient was using the same modality with which they had started PD (APD or CAPD). Patients were followed until their first modality switch. Differences in the pattern of SPA outcomes over time were tested using repeated-measures models adjusted for age, sex, comorbidity, primary kidney disease, and year of PD start. ♦ Results: The 59 CAPD patients enrolled were older than the 47 APD patients enrolled (mean age: 58 ± 14 years vs 49 ± 14 years; p < 0.01), and they had started PD earlier (mean start year: 2000 vs 2002). Over time, no differences in solute (p > 0.19) or fluid transport (p > 0.13) were observed. Similarly, free water transport (p = 0.43) and small-pore transport (p = 0.31) were not different between the modalities. Over time, patients on APD showed a faster decline in effective lymphatic absorption rate (ELAR: p = 0.02) and in transcapillary ultrafiltration (TCUF: p = 0.07, adjusted p = 0.05). Further adjustment did not change the results. ♦ Conclusions: Compared with patients starting on CAPD, those starting on APD experienced a faster decline in ELAR and TCUF. Other transport parameters were not different over time between the groups. PMID:22473037

An interactive program on digitizing historical seismograms

NASA Astrophysics Data System (ADS)

Xu, Yihe; Xu, Tao

2014-02-01

Retrieving information from analog seismograms is of great importance since they are considered as the unique sources that provide quantitative information of historical earthquakes. We present an algorithm for automatic digitization of the seismograms as an inversion problem that forms an interactive program using Matlab® GUI. The program integrates automatic digitization with manual digitization and users can easily switch between the two modalities and carry out different combinations for the optimal results. Several examples about applying the interactive program are given to illustrate the merits of the method.

Effective switching frequency multiplier inverter

DOEpatents

Su, Gui-Jia [Oak Ridge, TN; Peng, Fang Z [Okemos, MI

2007-08-07

A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

Double-Protected All-Inorganic Perovskite Nanocrystals by Crystalline Matrix and Silica for Triple-Modal Anti-Counterfeiting Codes.

PubMed

Xu, Leimeng; Chen, Jiawei; Song, Jizhong; Li, Jianhai; Xue, Jie; Dong, Yuhui; Cai, Bo; Shan, Qingsong; Han, Boning; Zeng, Haibo

2017-08-09

Novel fluorescence with highly covert and reliable features is quite desirable to combat the sophisticated counterfeiters. Herein, we report a simultaneously triple-modal fluorescent characteristic of CsPbBr 3 @Cs 4 PbBr 6 /SiO 2 by the excitation of thermal, ultraviolet (UV) and infrared (IR) light for the first time, which can be applied for the multiple modal anti-counterfeiting codes. The diphasic structure CsPbBr 3 @Cs 4 PbBr 6 nanocrystals (NCs) was synthesized via the typical reprecipitation method followed by uniformly encapsulation into silica microspheres. Cubic CsPbBr 3 is responsible for the functions of anti-counterfeiting, while Cs 4 PbBr 6 crystalline and SiO 2 are mainly to protect unstable CsPbBr 3 NCs from being destroyed by ambient conditions. The as-prepared CsPbBr 3 @Cs 4 PbBr 6 /SiO 2 NCs possess improved stability and are capable of forming printable ink with organic binders for patterns. Interestingly, the fluorescence of diphasic CsPbBr 3 @Cs 4 PbBr 6 /SiO 2 capsule patterns can be reversibly switched by the heating, UV, and IR light irradiation, which has been applied as triple-modal fluorescent anti-counterfeiting codes. The results demonstrate that the perovskite@silica capsules are highly promising for myriad applications in areas such as fluorescent anti-counterfeiting, optoelectronic devices, medical diagnosis, and biological imaging.

Physical modalities in chronic pain management.

PubMed

Rakel, Barbara; Barr, John O

2003-09-01

The following conclusions can be made based on review of the evidence: There is limited but positive evidence that select physical modalities are effective in managing chronic pain associated with specific conditions experienced by adults and older individuals. Overall, studies have provided the most support for the modality of therapeutic exercise. Different physical modalities have similar magnitudes of effects on chronic pain. Therefore, selection of the most appropriate physical modality may depend on the desired functional outcome for the patient, the underlying impairment, and the patient's preference or prior experience with the modality. Certain patient characteristics may decrease the effectiveness of physical modalities, as has been seen with TENS. These characteristics include depression, high trait anxiety, a powerful others locus of control, obesity, narcotic use, and neuroticism. The effect on pain by various modalities is generally strongest in the short-term period immediately after the intervention series, but effects can last as long as 1 year after treatment (e.g., with massage). Most research has tested the effect of physical modalities on chronic low back pain and knee OA. The effectiveness of physical modalities for other chronic pain conditions needs to be evaluated more completely. Older and younger adults often experience similar effects on their perception of pain from treatment with physical modalities. Therefore, use of these modalities for chronic pain in older adults is appropriate, but special precautions need to be taken. Practitioners applying physical modalities need formal training that includes the risks and precautions for these modalities. If practitioners lack formal training in the use of physical modalities, or if modality use is not within their scope of practice, it is important to consult with and refer patients to members of the team who have this specialized training. Use of a multidisciplinary approach to chronic pain management is of value for all adults and older individuals in particular [79-81]. Historically, physical therapists have been trained to evaluate and treat patients with the range of physical modalities discussed in this article. Although members of the nursing staff traditionally have used some of these modalities (e.g. some forms of heat or cold and massage), increasing numbers of nurses now are being trained to apply more specialized procedures (e.g., TENS). Healthcare professionals must be knowledgeable about the strength of evidence underlying the use of physical modalities for the management of chronic pain. Based on the limited research evidence available (especially related to assistive devices, orthotics, and thermal modalities), it often is difficult to accept or exclude select modalities as having a potential role in chronic pain management for adults and older individuals. Improved research methodologies are needed to address physical modality effectiveness better.

Neural practice effect during cross-modal selective attention: Supra-modal and modality-specific effects.

PubMed

Xia, Jing; Zhang, Wei; Jiang, Yizhou; Li, You; Chen, Qi

2018-05-16

Practice and experiences gradually shape the central nervous system, from the synaptic level to large-scale neural networks. In natural multisensory environment, even when inundated by streams of information from multiple sensory modalities, our brain does not give equal weight to different modalities. Rather, visual information more frequently receives preferential processing and eventually dominates consciousness and behavior, i.e., visual dominance. It remains unknown, however, the supra-modal and modality-specific practice effect during cross-modal selective attention, and moreover whether the practice effect shows similar modality preferences as the visual dominance effect in the multisensory environment. To answer the above two questions, we adopted a cross-modal selective attention paradigm in conjunction with the hybrid fMRI design. Behaviorally, visual performance significantly improved while auditory performance remained constant with practice, indicating that visual attention more flexibly adapted behavior with practice than auditory attention. At the neural level, the practice effect was associated with decreasing neural activity in the frontoparietal executive network and increasing activity in the default mode network, which occurred independently of the modality attended, i.e., the supra-modal mechanisms. On the other hand, functional decoupling between the auditory and the visual system was observed with the progress of practice, which varied as a function of the modality attended. The auditory system was functionally decoupled with both the dorsal and ventral visual stream during auditory attention while was decoupled only with the ventral visual stream during visual attention. To efficiently suppress the irrelevant visual information with practice, auditory attention needs to additionally decouple the auditory system from the dorsal visual stream. The modality-specific mechanisms, together with the behavioral effect, thus support the visual dominance model in terms of the practice effect during cross-modal selective attention. Copyright © 2018 Elsevier Ltd. All rights reserved.

Modal sound transmission loss of a single leaf panel: Effects of inter-modal coupling.

PubMed

Wang, Chong

2015-06-01

Sound transmission through a single leaf panel has mostly been discussed and explained by using the approaching wave concept, from which the well-known mass law can be derived. In this paper, the modal behavior in sound transmission coefficients is explored, and it is shown that the mutual modal radiation impedances in modal sound transmission coefficients may not be ignored even for a panel immersed in a light fluid. By introducing the equivalent modal impedance which incorporates the inter-modal coupling effect, an analytical expression for the modal sound transmission coefficient is derived, and the overall sound transmission coefficient is simply a modal superposition of modal sound transmission coefficients. A good correlation is obtained between analytical calculation and boundary element method. In addition, it is found that inter-modal coupling has noticeable effects in modal sound transmission coefficients in the subsonic region but may be ignored as modes become supersonic. It is also shown that the well-known mass law performance is attributed to all the supersonic modes.

Excitation of surface plasmons in Al-coated SNOM tips

NASA Astrophysics Data System (ADS)

Palm, Viktor; Rähn, Mihkel; Jäme, Joonas; Hizhnyakov, Vladimir

2012-10-01

The mesoscopic effect of spectral modulation occurring due to the interference of two photonic fiber modes filtered out by a metal-coated SNOM tip is used to observe the surface plasmon polariton (SPP) excitation in SNOM tips. In a spectrum of the broadband light transmitted by a SNOM tip a region of highly regular spectral modulation can be found, indicating the spectral interval in which only two photonic modes (apparently HE11 and TM01) are transmitted with significant and comparable amplitudes. The modulation period yields the value of optical path difference (OPD) for this pair of modes. Due to the multimode fiber's inherent modal dispersion, this OPD value depends linearly on the fiber tail length l. An additional contribution to OPD can be generated in a metal-coated SNOM tip due to a mode-dependent photon-plasmon coupling strength resulting in generation of SPPs with different propagation velocities. For an Al-coated 200 nm SNOM tip spectra of transmitted light have been registered for ten different l values. An extrapolation of the linear OPD (l) dependence to l=0 yields a significant residual OPD value, indicating according to our theoretical considerations a mode-selective SPP excitation in the metal-coated tip. The modal dispersion is shown to switch its sign in the SNOM tip. First results of analogous experiments with an Al-coated 150 nm SNOM tip confirm our conclusions.

Combining a CD20 Chimeric Antigen Receptor and an Inducible Caspase 9 Suicide Switch to Improve the Efficacy and Safety of T Cell Adoptive Immunotherapy for Lymphoma

PubMed Central

Budde, Lihua E.; Berger, Carolina; Lin, Yukang; Wang, Jinjuan; Lin, Xubin; Frayo, Shani E.; Brouns, Shaunda A.; Spencer, David M.; Till, Brian G.; Jensen, Michael C.; Riddell, Stanley R.; Press, Oliver W.

2013-01-01

Modification of T cells with chimeric antigen receptors (CAR) has emerged as a promising treatment modality for human malignancies. Integration of co-stimulatory domains into CARs can augment the activation and function of genetically targeted T cells against tumors. However, the potential for insertional mutagenesis and toxicities due to the infused cells have made development of safe methods for removing transferred cells an important consideration. We have genetically modified human T cells with a lentiviral vector to express a CD20-CAR containing both CD28 and CD137 co-stimulatory domains, a “suicide gene” relying on inducible activation of caspase 9 (iC9), and a truncated CD19 selectable marker. Rapid expansion (2000 fold) of the transduced T cells was achieved in 28 days after stimulation with artificial antigen presenting cells. Transduced T cells exhibited effective CD20-specific cytotoxic activity in vitro and in a mouse xenograft tumor model. Activation of the iC9 suicide switch resulted in efficient removal of transduced T cells both in vitro and in vivo. Our work demonstrates the feasibility and promise of this approach for treating CD20+ malignancies in a safe and more efficient manner. A phase I clinical trial using this approach in patients with relapsed indolent B-NHL is planned. PMID:24358223

Combining a CD20 chimeric antigen receptor and an inducible caspase 9 suicide switch to improve the efficacy and safety of T cell adoptive immunotherapy for lymphoma.

PubMed

Budde, Lihua E; Berger, Carolina; Lin, Yukang; Wang, Jinjuan; Lin, Xubin; Frayo, Shani E; Brouns, Shaunda A; Spencer, David M; Till, Brian G; Jensen, Michael C; Riddell, Stanley R; Press, Oliver W

2013-01-01

Modification of T cells with chimeric antigen receptors (CAR) has emerged as a promising treatment modality for human malignancies. Integration of co-stimulatory domains into CARs can augment the activation and function of genetically targeted T cells against tumors. However, the potential for insertional mutagenesis and toxicities due to the infused cells have made development of safe methods for removing transferred cells an important consideration. We have genetically modified human T cells with a lentiviral vector to express a CD20-CAR containing both CD28 and CD137 co-stimulatory domains, a "suicide gene" relying on inducible activation of caspase 9 (iC9), and a truncated CD19 selectable marker. Rapid expansion (2000 fold) of the transduced T cells was achieved in 28 days after stimulation with artificial antigen presenting cells. Transduced T cells exhibited effective CD20-specific cytotoxic activity in vitro and in a mouse xenograft tumor model. Activation of the iC9 suicide switch resulted in efficient removal of transduced T cells both in vitro and in vivo. Our work demonstrates the feasibility and promise of this approach for treating CD20(+) malignancies in a safe and more efficient manner. A phase I clinical trial using this approach in patients with relapsed indolent B-NHL is planned.

The framing effect in a monetary gambling task is robust in minimally verbal language switching contexts.

PubMed

Korn, Christoph W; Heekeren, Hauke R; Oganian, Yulia

2018-04-01

Decision-making biases, in particular the framing effect, can be altered in foreign language settings (foreign language effect) and following switching between languages (the language switching effect on framing). Recently, it has been suggested that the framing effect is only affected by foreign language use if the task is presented in a rich textual form. Here, we assess whether an elaborate verbal task is also a prerequisite for the language switching effect on framing. We employed a financial gambling task that induces a robust framing effect but is less verbal than the classical framing paradigms (e.g., the Asian disease problem). We conducted an online experiment ( n = 485), where we orthogonally manipulated language use and language switching between trials. The results showed no effects of foreign language use or language switching throughout the experiment. This online result was confirmed in a laboratory experiment ( n = 27). Overall, we find that language switching does not reduce the framing effect in a paradigm with little verbal content and thus that language switching effects seem contingent on the amount of verbal processing required.

Speech versus manual control of camera functions during a telerobotic task

NASA Technical Reports Server (NTRS)

Bierschwale, John M.; Sampaio, Carlos E.; Stuart, Mark A.; Smith, Randy L.

1989-01-01

Voice input for control of camera functions was investigated in this study. Objective were to (1) assess the feasibility of a voice-commanded camera control system, and (2) identify factors that differ between voice and manual control of camera functions. Subjects participated in a remote manipulation task that required extensive camera-aided viewing. Each subject was exposed to two conditions, voice and manual input, with a counterbalanced administration order. Voice input was found to be significantly slower than manual input for this task. However, in terms of remote manipulator performance errors and subject preference, there was no difference between modalities. Voice control of continuous camera functions is not recommended. It is believed that the use of voice input for discrete functions, such as multiplexing or camera switching, could aid performance. Hybrid mixes of voice and manual input may provide the best use of both modalities. This report contributes to a better understanding of the issues that affect the design of an efficient human/telerobot interface.

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

Slipchenko, S. O., E-mail: serghpl@mail.ioffe.ru; Podoskin, A. A.; Vinokurov, D. A.

Radiative characteristics of semiconductor stripe-contact lasers operating under quenching conditions of Fabry-Perot-mode lasing are studied. It is found that reversible turning off of Fabry-Perot-mode lasing is caused by switching to closed-mode lasing. Radiative characteristics of the closed mode are controlled by the mode structure with the close-to-zero loss for radiation output, which covers the entire crystal. The main threshold conditions of closed-mode lasing are a decrease in interband absorption in the passive region and an increase in the modal gain of the closed-mode lasing line. It is shown that a decrease in interband absorption in the passive region can bemore » provided by both spontaneous emission from the injection region and lasing-mode photons. An increase in the modal gain of the closed-mode lasing line is provided by shifting the energy minima of the conduction band and maxima of the valence band of the injection region with respect to the energy bands of the passive region.« less

Lasers for treatment of melasma and post-inflammatory hyperpigmentation.

PubMed

Arora, Pooja; Sarkar, Rashmi; Garg, Vijay K; Arya, Latika

2012-04-01

Hyperpigmentary disorders, especially melasma and post-inflammatory hyperpigmentation (PIH), cause significant social and emotional stress to the patients. Although many treatment modalities have been developed for melasma and PIH, its management still remains a challenge due to its recurrent and refractory nature. With the advent of laser technology, the treatment options have increased especially for dermal or mixed melasma. To review the literature on the use of cutaneous lasers for melasma and PIH. We carried out a PubMed search using following terms "lasers, IPL, melasma, PIH". We cited the use of various lasers to treat melasma and PIH, including Q-switched Nd:YAG, Q-switched alexandrite, pulsed dye laser, and various fractional lasers. We describe the efficacy and safety of these lasers for the treatment of hyperpigmentation. Choosing the appropriate laser and the correct settings is vital in the treatment of melasma. The use of latter should be restricted to cases unresponsive to topical therapy or chemical peels. Appropriate maintenance therapy should be selected to avoid relapse of melasma.

Memristive Ion Channel-Doped Biomembranes as Synaptic Mimics.

PubMed

Najem, Joseph S; Taylor, Graham J; Weiss, Ryan J; Hasan, Md Sakib; Rose, Garrett; Schuman, Catherine D; Belianinov, Alex; Collier, C Patrick; Sarles, Stephen A

2018-05-22

Solid-state neuromorphic systems based on transistors or memristors have yet to achieve the interconnectivity, performance, and energy efficiency of the brain due to excessive noise, undesirable material properties, and nonbiological switching mechanisms. Here we demonstrate that an alamethicin-doped, synthetic biomembrane exhibits memristive behavior, emulates key synaptic functions including paired-pulse facilitation and depression, and enables learning and computing. Unlike state-of-the-art devices, our two-terminal, biomolecular memristor features similar structure (biomembrane), switching mechanism (ion channels), and ionic transport modality as biological synapses while operating at considerably lower power. The reversible and volatile voltage-driven insertion of alamethicin peptides into an insulating lipid bilayer creates conductive pathways that exhibit pinched current-voltage hysteresis at potentials above their insertion threshold. Moreover, the synapse-like dynamic properties of the biomolecular memristor allow for simplified learning circuit implementations. Low-power memristive devices based on stimuli-responsive biomolecules represent a major advance toward implementation of full synaptic functionality in neuromorphic hardware.

Lasers for Treatment of Melasma and Post-Inflammatory Hyperpigmentation

PubMed Central

Arora, Pooja; Sarkar, Rashmi; Garg, Vijay K; Arya, Latika

2012-01-01

Hyperpigmentary disorders, especially melasma and post-inflammatory hyperpigmentation (PIH), cause significant social and emotional stress to the patients. Although many treatment modalities have been developed for melasma and PIH, its management still remains a challenge due to its recurrent and refractory nature. With the advent of laser technology, the treatment options have increased especially for dermal or mixed melasma. To review the literature on the use of cutaneous lasers for melasma and PIH. We carried out a PubMed search using following terms “lasers, IPL, melasma, PIH”. We cited the use of various lasers to treat melasma and PIH, including Q-switched Nd:YAG, Q-switched alexandrite, pulsed dye laser, and various fractional lasers. We describe the efficacy and safety of these lasers for the treatment of hyperpigmentation. Choosing the appropriate laser and the correct settings is vital in the treatment of melasma. The use of latter should be restricted to cases unresponsive to topical therapy or chemical peels. Appropriate maintenance therapy should be selected to avoid relapse of melasma. PMID:23060704

Focal switching of photochromic fluorescent proteins enables multiphoton microscopy with superior image contrast.

PubMed

Kao, Ya-Ting; Zhu, Xinxin; Xu, Fang; Min, Wei

2012-08-01

Probing biological structures and functions deep inside live organisms with light is highly desirable. Among the current optical imaging modalities, multiphoton fluorescence microscopy exhibits the best contrast for imaging scattering samples by employing a spatially confined nonlinear excitation. However, as the incident laser power drops exponentially with imaging depth into the sample due to the scattering loss, the out-of-focus background eventually overwhelms the in-focus signal, which defines a fundamental imaging-depth limit. Herein we significantly improve the image contrast for deep scattering samples by harnessing reversibly switchable fluorescent proteins (RSFPs) which can be cycled between bright and dark states upon light illumination. Two distinct techniques, multiphoton deactivation and imaging (MPDI) and multiphoton activation and imaging (MPAI), are demonstrated on tissue phantoms labeled with Dronpa protein. Such a focal switch approach can generate pseudo background-free images. Conceptually different from wave-based approaches that try to reduce light scattering in turbid samples, our work represents a molecule-based strategy that focused on imaging probes.

Focal switching of photochromic fluorescent proteins enables multiphoton microscopy with superior image contrast

PubMed Central

Kao, Ya-Ting; Zhu, Xinxin; Xu, Fang; Min, Wei

2012-01-01

Probing biological structures and functions deep inside live organisms with light is highly desirable. Among the current optical imaging modalities, multiphoton fluorescence microscopy exhibits the best contrast for imaging scattering samples by employing a spatially confined nonlinear excitation. However, as the incident laser power drops exponentially with imaging depth into the sample due to the scattering loss, the out-of-focus background eventually overwhelms the in-focus signal, which defines a fundamental imaging-depth limit. Herein we significantly improve the image contrast for deep scattering samples by harnessing reversibly switchable fluorescent proteins (RSFPs) which can be cycled between bright and dark states upon light illumination. Two distinct techniques, multiphoton deactivation and imaging (MPDI) and multiphoton activation and imaging (MPAI), are demonstrated on tissue phantoms labeled with Dronpa protein. Such a focal switch approach can generate pseudo background-free images. Conceptually different from wave-based approaches that try to reduce light scattering in turbid samples, our work represents a molecule-based strategy that focused on imaging probes. PMID:22876358

Survival on Home Dialysis in New Zealand

PubMed Central

Marshall, Mark R.; Walker, Rachael C.; Polkinghorne, Kevan R.; Lynn, Kelvin L.

2014-01-01

Background New Zealand (NZ) has a high prevalence of both peritoneal dialysis (PD) and home haemodialysis (HD) relative to other countries, and probably less selection bias. We aimed to determine if home dialysis associates with better survival than facility HD by simultaneous comparisons of the three modalities. Methods We analysed survival by time-varying dialysis modality in New Zealanders over a 15-year period to 31-Dec-2011, adjusting for patient co-morbidity by Cox proportional hazards multivariate regression. Results We modelled 6,419 patients with 3,254 deaths over 20,042 patient-years of follow-up. Patients treated with PD and facility HD are similar; those on home HD are younger and healthier. Compared to facility HD, home dialysis (as a unified category) associates with an overall 13% lower mortality risk. Home HD associates with a 52% lower mortality risk. PD associates with a 20% lower mortality risk in the early period (<3 years) that is offset by a 33% greater mortality risk in the late period (>3 years), with no overall net effect. There was effect modification and less observable benefit associated with PD in those with diabetes mellitus, co-morbidity, and in NZ Maori and Pacific People. There was no effect modification by age or by era. Conclusion Our study supports the culture of home dialysis in NZ, and suggests that the extent and duration of survival benefit associated with early PD may be greater than appreciated. We are planning further analyses to exclude residual confounding from unmeasured co-morbidity and other sociodemographic factors using database linkage to NZ government datasets. Finally, our results suggest further research into the practice of PD in NZ Maori and Pacific People, as well as definitive study to determine the best timing for switching from PD in the late phase. PMID:24806458

Transcranial direct-current stimulation (tDCS) for bipolar depression: A systematic review and meta-analysis.

PubMed

Dondé, Clément; Amad, Ali; Nieto, Isabel; Brunoni, André Russowsky; Neufeld, Nicholas H; Bellivier, Frank; Poulet, Emmanuel; Geoffroy, Pierre-Alexis

2017-08-01

Bipolar disorder (BD) is a severe and recurrent brain disorder that can manifest in manic or depressive episodes. Transcranial Direct Current Stimulation (tDCS) has been proposed as a novel therapeutic modality for patients experiencing bipolar depression, for which standard treatments are often inefficient. While several studies have been conducted in this patient group, there has been no systematic review or meta-analysis that specifically examines bipolar depression. We aimed to address this gap in the literature and evaluated the efficacy and tolerability of tDCS in patients fulfilling DSM-IV-TR criteria for BD I, II, or BD not otherwise specified (NOS). We systematically searched the literature from April 2002 to November 2016 to identify relevant publications for inclusion in our systematic review and meta-analysis. Effect sizes for depression rating-scale scores were expressed as the standardized mean difference (SMD) before and after tDCS. Thirteen of 382 identified studies met eligibility criteria for our systematic review. The meta-analysis included 46 patients from 7 studies with depression rating-scale scores pre- and post-tDCS. Parameters of tDCS procedures were heterogeneous. Depression scores decreased significantly with a medium effect size after acute-phase of treatment (SMD 0.71 [0.25-1.18], z=3.00, p=0.003) and at the furthest endpoint (SMD 1.27 [0.57-1.97], z=3.57, p=0.0004). Six cases of affective switching under tDCS treatment protocols were observed. Depressive symptoms respond to tDCS in patients with BD. Additional studies, and particularly randomized controlled trials, are needed to clarify the effectiveness of tDCS in bipolar depression, the frequency of tDCS-emergent hypomania/mania, and which tDCS modalities are most efficient. Copyright © 2017 Elsevier Inc. All rights reserved.

The role of subjective frequency in language switching: An ERP investigation using masked priming

PubMed Central

Chauncey, Krysta; Grainger, Jonathan; Holcomb, Phillip J.

2012-01-01

Two experiments examined the nature of language-switching effects in a priming paradigm with event-related brain potential (ERP) recordings. primes and targets were always unrelated words but could be either from the same or different languages (Experiment 1) or from the same or a different frequency range (Experiment 2). Effects of switching language across prime and target differed as a function of the direction of the switch and prime duration in Experiment 1. Effects tended to be stronger with 100-ms prime durations than with 50-ms durations, and the expected pattern of greater negativity in the switch condition appeared earlier when primes were in L1 and targets in L2 than vice versa. Experiment 2 examined whether these language-switching effects could be due to differences in the subjective frequency of words in a bilingual’s two languages, by testing a frequency-switching manipulation within the L1. Effects of frequency switching were evident in the ERP waveforms, but the pattern did not resemble the language-switching effects, therefore suggesting that different mechanisms are at play. PMID:21264577

The Perceptual Basis of the Modality Effect in Multimedia Learning

ERIC Educational Resources Information Center

Rummer, Ralf; Schweppe, Judith; Furstenberg, Anne; Scheiter, Katharina; Zindler, Antje

2011-01-01

Various studies have demonstrated an advantage of auditory over visual text modality when learning with texts and pictures. To explain this modality effect, two complementary assumptions are proposed by cognitive theories of multimedia learning: first, the visuospatial load hypothesis, which explains the modality effect in terms of visuospatial…

Mechanical switching of ferroelectric domains beyond flexoelectricity

NASA Astrophysics Data System (ADS)

Chen, Weijin; Liu, Jianyi; Ma, Lele; Liu, Linjie; Jiang, G. L.; Zheng, Yue

2018-02-01

The resurgence of interest in flexoelectricity has prompted discussions on the feasibility of switching ferroelectric domains 'non-electrically'. In this work, we perform three-dimensional thermodynamic simulations in combination with ab initio calculations and effective Hamiltonian simulations to demonstrate the great effects of surface screening and surface bonding on ferroelectric domain switching triggered by local tip loading. A three-dimensional simulation scheme has been developed to capture the tip-induced domain switching behavior in ferroelectric thin films by adequately taking into account the surface screening effect and surface bonding effect of the ferroelectric film, as well as the finite elastic stiffness of the substrate and the electrode layers. The major findings are as follows. (i) Compared with flexoelectricity, surface effects can be overwhelming and lead to much more efficient mechanical switching caused by tip loading. (ii) The surface-assisted mechanical switching can be bi-directional without the necessity of reversing strain gradients. (iii) A mode transition from local to propagating domain switching occurs when the screening below a critical value. A ripple effect of domain switching appears with the formation of concentric loop domains. (iv) The ripple effect can lead to 'domain interference' and a deterministic writing of confined loop domain patterns by local excitations. Our study reveals the hidden switching mechanisms of ferroelectric domains and the possible roles of surface in mechanical switching. The ripple effect of domain switching, which is believed to be general in dipole systems, broadens our current knowledge of domain engineering.

Attentional capture by taboo words: A functional view of auditory distraction.

PubMed

Röer, Jan P; Körner, Ulrike; Buchner, Axel; Bell, Raoul

2017-06-01

It is well established that task-irrelevant, to-be-ignored speech adversely affects serial short-term memory (STM) for visually presented items compared with a quiet control condition. However, there is an ongoing debate about whether the semantic content of the speech has the capacity to capture attention and to disrupt memory performance. In the present article, we tested whether taboo words are more difficult to ignore than neutral words. Taboo words or neutral words were presented as (a) steady state sequences in which the same distractor word was repeated, (b) changing state sequences in which different distractor words were presented, and (c) auditory deviant sequences in which a single distractor word deviated from a sequence of repeated words. Experiments 1 and 2 showed that taboo words disrupted performance more than neutral words. This taboo effect did not habituate and it did not differ between individuals with high and low working memory capacity. In Experiments 3 and 4, in which only a single deviant taboo word was presented, no taboo effect was obtained. These results do not support the idea that the processing of the auditory distractors' semantic content is the result of occasional attention switches to the auditory modality. Instead, the overall pattern of results is more in line with a functional view of auditory distraction, according to which the to-be-ignored modality is routinely monitored for potentially important stimuli (e.g., self-relevant or threatening information), the detection of which draws processing resources away from the primary task. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Intermittent impact dynamics of a cantilever scanning a surface at high speed

NASA Astrophysics Data System (ADS)

Dey, S.; Kartik, V.

2018-03-01

In contact-mode scanning probe microscopy (SPM), the cantilever's dynamics are conventionally investigated by assuming the tip to be always in contact with the sample's surface. At high scanning speeds, however, the cantilever's inertia becomes dominant and the tip can therefore completely detach from the surface and start impacting upon it. Experiments at the macro-scale cannot emulate the complex micro-scale dynamics, as the system exhibits negligible effects due to meniscus forces and the surrounding medium's squeeze film damping; however, they can provide qualitative insight into the cantilever's dynamics at high frequencies, corresponding to those likely to be excited during video-rate SPM imaging. This paper investigates such intermittent impact dynamics for an upscaled cantilever, analytically, numerically, and experimentally. In contact-mode scanning, a critical scan speed exists beyond which the cantilever's tip loses contact with the sample's surface; a closed-form expression for this contact loss frequency is derived. At high scan speeds, impacts cause the cantilever to switch between different contact regimes: in-, off-, and grazing-contact; within each regime, the system's modal configuration is different. Experimentally-obtained Poincare maps indicate quasi-periodic behaviour at frequencies for which the response is repetitive, as is also predicted by the model. Intermittent impacts excite the sub- and super-harmonics of the excitation frequency, which are related to the natural frequencies of different system configurations based on the "effective" tip-end boundary conditions. The cantilever's response exhibits several phenomena, such as modal transition, beating, grazing, and possible chaotic behaviour, depending upon the relation between the excitation harmonics and the natural frequencies.

Effect of tungsten implantation on the switching parameters in V2O5 films

NASA Astrophysics Data System (ADS)

Burdyukh, S. V.; Berezina, O. Ya.; Pergament, A. L.

2017-11-01

The paper examines the effect of doping with tungsten on switching in hydrated vanadium pentoxide films. The switching effect is associated with the metal-insulator transition in a vanadium dioxide channel that forms in the initial film due to the process of electrical forming (EF). Doping is carried out by the plasma immersion ion implantation method. It is shown that implanting small tungsten doses improves the switching parameters after EF. When implanting large doses, switching is observed without EF, and if EF is applied, the switching effect, on the contrary, disappears.

The preparation effect in task switching: carryover of SOA.

PubMed

Altmann, Erik M

2004-01-01

A common finding in task-switching studies is switch preparation (commonly known as the preparation effect), in which a longer interval between task cue and trial stimulus (i.e., a longer stimulus onset asynchrony, or SOA) reduces the cost of switching to a different task. Three experiments link switch preparation to within-subjects manipulations of SOA. In Experiment 1, SOA was randomized within subjects, producing switch preparation that was more pronounced when the SOA switched from the previous trial than when the SOA repeated. In Experiment 2, SOA was blocked within subjects, producing switch preparation but not on the first block of trials. In Experiment 3, SOA was manipulated between subjects with sufficient statistical power to detect switch preparation, but the effect was absent. The results favor an encoding view of cognitive control, but show that any putative switching mechanism reacts lazily when exposed to only one SOA.

Bulky Polar Additives That Greatly Reduce the Viscosity of Concentrated Solutions of Therapeutic Monoclonal Antibodies.

PubMed

Larson, Alyssa M; Weight, Alisha K; Love, Kevin; Bonificio, Amanda; Wescott, Charles R; Klibanov, Alexander M

2017-05-01

The viscosity of concentrated aqueous solutions of 3 clinical monoclonal antibodies (mAbs), Erbitux®, Herceptin®, and Rituxan®, has been reduced up to over 10-fold by adding certain bulky polar additives instead of saline at isotonic levels. Because these additives are also found not to compromise mAbs' stability against aggregation induced by stresses, a drug-delivery modality switch from intravenous infusions to more convenient and inexpensive parenteral options like subcutaneous injections may become possible. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Sensor fusion and augmented reality with the SAFIRE system

NASA Astrophysics Data System (ADS)

Saponaro, Philip; Treible, Wayne; Phelan, Brian; Sherbondy, Kelly; Kambhamettu, Chandra

2018-04-01

The Spectrally Agile Frequency-Incrementing Reconfigurable (SAFIRE) mobile radar system was developed and exercised at an arid U.S. test site. The system can detect hidden target using radar, a global positioning system (GPS), dual stereo color cameras, and dual stereo thermal cameras. An Augmented Reality (AR) software interface allows the user to see a single fused video stream containing the SAR, color, and thermal imagery. The stereo sensors allow the AR system to display both fused 2D imagery and 3D metric reconstructions, where the user can "fly" around the 3D model and switch between the modalities.

Intra-operative label-free multimodal multiphoton imaging of breast cancer margins and microenvironment (Conference Presentation)

NASA Astrophysics Data System (ADS)

Sun, Yi; You, Sixian; Tu, Haohua; Spillman, Darold R.; Marjanovic, Marina; Chaney, Eric J.; Liu, George Z.; Ray, Partha S.; Higham, Anna; Boppart, Stephen A.

2017-02-01

Label-free multi-photon imaging has been a powerful tool for studying tissue microstructures and biochemical distributions, particularly for investigating tumors and their microenvironments. However, it remains challenging for traditional bench-top multi-photon microscope systems to conduct ex vivo tumor tissue imaging in the operating room due to their bulky setups and laser sources. In this study, we designed, built, and clinically demonstrated a portable multi-modal nonlinear label-free microscope system that combined four modalities, including two- and three- photon fluorescence for studying the distributions of FAD and NADH, and second and third harmonic generation, respectively, for collagen fiber structures and the distribution of micro-vesicles found in tumors and the microenvironment. Optical realignments and switching between modalities were motorized for more rapid and efficient imaging and for a light-tight enclosure, reducing ambient light noise to only 5% within the brightly lit operating room. Using up to 20 mW of laser power after a 20x objective, this system can acquire multi-modal sets of images over 600 μm × 600 μm at an acquisition rate of 60 seconds using galvo-mirror scanning. This portable microscope system was demonstrated in the operating room for imaging fresh, resected, unstained breast tissue specimens, and for assessing tumor margins and the tumor microenvironment. This real-time label-free nonlinear imaging system has the potential to uniquely characterize breast cancer margins and the microenvironment of tumors to intraoperatively identify structural, functional, and molecular changes that could indicate the aggressiveness of the tumor.

Feature Integration and Task Switching: Diminished Switch Costs after Controlling for Stimulus, Response, and Cue Repetitions

PubMed Central

Schmidt, James R.; Liefooghe, Baptist

2016-01-01

This report presents data from two versions of the task switching procedure in which the separate influence of stimulus repetitions, response key repetitions, conceptual response repetitions, cue repetitions, task repetitions, and congruency are considered. Experiment 1 used a simple alternating runs procedure with parity judgments of digits and consonant/vowel decisions of letters as the two tasks. Results revealed sizable effects of stimulus and response repetitions, and controlling for these effects reduced the switch cost. Experiment 2 was a cued version of the task switch paradigm with parity and magnitude judgments of digits as the two tasks. Results again revealed large effects of stimulus and response repetitions, in addition to cue repetition effects. Controlling for these effects again reduced the switch cost. Congruency did not interact with our novel “unbiased” measure of switch costs. We discuss how the task switch paradigm might be thought of as a more complex version of the feature integration paradigm and propose an episodic learning account of the effect. We further consider to what extent appeals to higher-order control processes might be unnecessary and propose that controls for feature integration biases should be standard practice in task switching experiments. PMID:26964102

[Reason for "choosing" peritoneal dialysis: exhaustion of vascular access for hemodialysis?].

PubMed

Rocha, Paulo Novis; Sallenave, Mila; Casqueiro, Verena; Campelo Neto, Bolivar; Presídio, Sérgio

2010-03-01

Little is known about the prognosis of patients beginning peritoneal dialysis (PD) as their last alternative. To describe the clinical-demographic profile of patients switching from hemodialysis (HD) to PD, due to exhaustion of the HD vascular access, and the occurrence of peritonitis among them. Review of the medical records of all patients in the PD program of the Hospital Roberto Santos in the city of Salvador, state of Bahia, Brazil. The study comprised 22 patients (median age, 47.9 years), 54.5% of whom were men, 84.2%, black or mulattoes, and 68.2% originated from the inner Bahia state. Peritoneal dialysis was the initial modality of renal substitutive therapy (RST) in only four of those patients. The remaining 18 patients began RST through HD, mainly on an emergency basis and by using double-lumen catheter (DLC). In a median of 7.7 months on HD, most patients (64.7%) used four or more DLCs. In only 7/18 (39%) patients, the switch from HD to PD was based on the patient';s choice; in most cases, 11/18 (61%), the reason for switching to PD was exhaustion of HD vascular access. Peritonitis was more frequent in patients switching to PD due to exhaustion of HD vascular access than in the rest of the group. Initiating RST on an emergency basis through HD and using DLC may lead to a fast exhaustion of vascular access, leaving PD as the only viable option. This inadequate mode of patient "selection" for PD is associated with a higher risk for peritonitis.

Should Animals Navigating Over Short Distances Switch to a Magnetic Compass Sense?

PubMed Central

Wyeth, Russell C.

2010-01-01

Magnetoreception can play a substantial role in long distance navigation by animals. I hypothesize that locomotion guided by a magnetic compass sense could also play a role in short distance navigation. Animals identify mates, prey, or other short distance navigational goals using different sensory modalities (olfaction, vision, audition, etc.) to detect sensory cues associated with those goals. In conditions where these cues become unreliable for navigation (due to flow changes, obstructions, noise interference, etc.), switching to a magnetic compass sense to guide locomotion toward the navigational goals could be beneficial. Using simulations based on known locomotory and flow parameters, I show this strategy has strong theoretical benefits for the nudibranch mollusk Tritonia diomedea navigating toward odor sources in variable flow. A number of other animals may garner similar benefits, particularly slow-moving species in environments with rapidly changing cues relevant for navigation. Faster animals might also benefit from switching to a magnetic compass sense, provided the initial cues used for navigation (acoustic signals, odors, etc.) are intermittent or change rapidly enough that the entire navigation behavior cannot be guided by a continuously detectable cue. Examination of the relative durations of navigational tasks, the persistence of navigational cues, and the stability of both navigators and navigational targets will identify candidates with the appropriate combination of unreliable initial cues and relatively immobile navigational goals for which this hypothetical behavior could be beneficial. Magnetic manipulations can then test whether a switch to a magnetic compass sense occurs. This hypothesis thus provides an alternative when considering the behavioral significance of a magnetic compass sense in animals. PMID:20740070

Modalities of Thinking: State and Trait Effects on Cross-Frequency Functional Independent Brain Networks.

PubMed

Milz, Patricia; Pascual-Marqui, Roberto D; Lehmann, Dietrich; Faber, Pascal L

2016-05-01

Functional states of the brain are constituted by the temporally attuned activity of spatially distributed neural networks. Such networks can be identified by independent component analysis (ICA) applied to frequency-dependent source-localized EEG data. This methodology allows the identification of networks at high temporal resolution in frequency bands of established location-specific physiological functions. EEG measurements are sensitive to neural activity changes in cortical areas of modality-specific processing. We tested effects of modality-specific processing on functional brain networks. Phasic modality-specific processing was induced via tasks (state effects) and tonic processing was assessed via modality-specific person parameters (trait effects). Modality-specific person parameters and 64-channel EEG were obtained from 70 male, right-handed students. Person parameters were obtained using cognitive style questionnaires, cognitive tests, and thinking modality self-reports. EEG was recorded during four conditions: spatial visualization, object visualization, verbalization, and resting. Twelve cross-frequency networks were extracted from source-localized EEG across six frequency bands using ICA. RMANOVAs, Pearson correlations, and path modelling examined effects of tasks and person parameters on networks. Results identified distinct state- and trait-dependent functional networks. State-dependent networks were characterized by decreased, trait-dependent networks by increased alpha activity in sub-regions of modality-specific pathways. Pathways of competing modalities showed opposing alpha changes. State- and trait-dependent alpha were associated with inhibitory and automated processing, respectively. Antagonistic alpha modulations in areas of competing modalities likely prevent intruding effects of modality-irrelevant processing. Considerable research suggested alpha modulations related to modality-specific states and traits. This study identified the distinct electrophysiological cortical frequency-dependent networks within which they operate.

Effects of auditory and visual modalities in recall of words.

PubMed

Gadzella, B M; Whitehead, D A

1975-02-01

Ten experimental conditions were used to study the effects of auditory and visual (printed words, uncolored and colored pictures) modalities and their various combinations with college students. A recall paradigm was employed in which subjects responded in a written test. Analysis of data showed the auditory modality was superior to visual (pictures) ones but was not significantly different from visual (printed words) modality. In visual modalities, printed words were superior to colored pictures. Generally, conditions with multiple modes of representation of stimuli were significantly higher than for conditions with single modes. Multiple modalities, consisting of two or three modes, did not differ significantly from each other. It was concluded that any two modalities of the stimuli presented simultaneously were just as effective as three in recall of stimulus words.

Modelling switching-time effects in high-frequency power conditioning networks

NASA Technical Reports Server (NTRS)

Owen, H. A.; Sloane, T. H.; Rimer, B. H.; Wilson, T. G.

1979-01-01

Power transistor networks which switch large currents in highly inductive environments are beginning to find application in the hundred kilohertz switching frequency range. Recent developments in the fabrication of metal-oxide-semiconductor field-effect transistors in the power device category have enhanced the movement toward higher switching frequencies. Models for switching devices and of the circuits in which they are imbedded are required to properly characterize the mechanisms responsible for turning on and turning off effects. Easily interpreted results in the form of oscilloscope-like plots assist in understanding the effects of parametric studies using topology oriented computer-aided analysis methods.

Influence of UV illumination on the cold temperature operation of a LiNbO(3) Q-switched Nd:YAG laser.

PubMed

Cole, Brian; Goldberg, Lew; King, Vernon; Leach, Jeff

2010-04-26

UV illumination of a lithium niobate Q-switch was demonstrated as an effective means to eliminate a loss in hold-off and associated prelasing that occurs under cold temperature operation of Q-switched lasers. This degradation occurs due to the pyroelectric effect, where an accumulation of charge on crystal faces results in a reduction in the Q-switch hold-off and a spatially variable loss of the Q-switch in its high-transmission state, both resulting in lowering of the maximum Q-switched pulse energy. With UV illumination, the resulting creation of photo-generated carriers was shown to be effective in eliminating both of these effects. A Q-switched Nd:YAG laser utilizing UV-illuminated LiNbO(3) was shown to operate under cold temperatures without prelasing or spatially variable loss.

Coactivation of cognitive control networks during task switching.

PubMed

Yin, Shouhang; Deák, Gedeon; Chen, Antao

2018-01-01

The ability to flexibly switch between tasks is considered an important component of cognitive control that involves frontal and parietal cortical areas. The present study was designed to characterize network dynamics across multiple brain regions during task switching. Functional magnetic resonance images (fMRI) were captured during a standard rule-switching task to identify switching-related brain regions. Multiregional psychophysiological interaction (PPI) analysis was used to examine effective connectivity between these regions. During switching trials, behavioral performance declined and activation of a generic cognitive control network increased. Concurrently, task-related connectivity increased within and between cingulo-opercular and fronto-parietal cognitive control networks. Notably, the left inferior frontal junction (IFJ) was most consistently coactivated with the 2 cognitive control networks. Furthermore, switching-dependent effective connectivity was negatively correlated with behavioral switch costs. The strength of effective connectivity between left IFJ and other regions in the networks predicted individual differences in switch costs. Task switching was supported by coactivated connections within cognitive control networks, with left IFJ potentially acting as a key hub between the fronto-parietal and cingulo-opercular networks. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

State Recognition of High Voltage Isolation Switch Based on Background Difference and Iterative Search

NASA Astrophysics Data System (ADS)

Xu, Jiayuan; Yu, Chengtao; Bo, Bin; Xue, Yu; Xu, Changfu; Chaminda, P. R. Dushantha; Hu, Chengbo; Peng, Kai

2018-03-01

The automatic recognition of the high voltage isolation switch by remote video monitoring is an effective means to ensure the safety of the personnel and the equipment. The existing methods mainly include two ways: improving monitoring accuracy and adopting target detection technology through equipment transformation. Such a method is often applied to specific scenarios, with limited application scope and high cost. To solve this problem, a high voltage isolation switch state recognition method based on background difference and iterative search is proposed in this paper. The initial position of the switch is detected in real time through the background difference method. When the switch starts to open and close, the target tracking algorithm is used to track the motion trajectory of the switch. The opening and closing state of the switch is determined according to the angle variation of the switch tracking point and the center line. The effectiveness of the method is verified by experiments on different switched video frames of switching states. Compared with the traditional methods, this method is more robust and effective.

Project MICAS: a multivendor open-system incremental approach to implementing an integrated enterprise-wide PACS: works in progress

NASA Astrophysics Data System (ADS)

Smith, Edward M.; Wright, Jeffrey; Fontaine, Marc T.; Robinson, Arvin E.

1998-07-01

The Medical Information, Communication and Archive System (MICAS) is a multi-vendor incremental approach to PACS. MICAS is a multi-modality integrated image management system that incorporates the radiology information system (RIS) and radiology image database (RID) with future 'hooks' to other hospital databases. Even though this approach to PACS is more risky than a single-vendor turn-key approach, it offers significant advantages. The vendors involved in the initial phase of MICAS are IDX Corp., ImageLabs, Inc. and Digital Equipment Corp (DEC). The network architecture operates at 100 MBits per sec except between the modalities and the stackable intelligent switch which is used to segment MICAS by modality. Each modality segment contains the acquisition engine for the modality, a temporary archive and one or more diagnostic workstations. All archived studies are available at all workstations, but there is no permanent archive at this time. At present, the RIS vendor is responsible for study acquisition and workflow as well as maintenance of the temporary archive. Management of study acquisition, workflow and the permanent archive will become the responsibility of the archive vendor when the archive is installed in the second quarter of 1998. The modalities currently interfaced to MICAS are MRI, CT and a Howtek film digitizer with Nuclear Medicine and computed radiography (CR) to be added when the permanent archive is installed. There are six dual-monitor diagnostic workstations which use ImageLabs Shared Vision viewer software located in MRI, CT, Nuclear Medicine, musculoskeletal reading areas and two in Radiology's main reading area. One of the major lessons learned to date is that the permanent archive should have been part of the initial MICAS installation and the archive vendor should have been responsible for image acquisition rather than the RIS vendor. Currently an archive vendor is being selected who will be responsible for the management of the archive plus the HIS/RIS interface, image acquisition, modality work list manager and interfacing to the current DICOM viewer software. The next phase of MICAS will include interfacing ultrasound, locating servers outside of the Radiology LAN to support the distribution of images and reports to the clinical floors and physician offices both within and outside of the University of Rochester Medical Center (URMC) campus and the teaching archive.

PET/MR Synchronization by Detection of Switching Gradients

NASA Astrophysics Data System (ADS)

Weissler, Bjoern; Gebhardt, Pierre; Lerche, Christoph W.; Soultanidis, Georgios M.; Wehner, Jakob; Heberling, Dirk; Schulz, Volkmar

2015-06-01

The full potential of simultaneous Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) acquisition, such as dynamic studies or motion compensation, can only be explored if the data of both modalities is temporally synchronized. As such hybrid imaging systems are commonly realized as custom-made PET inserts for commercially available MRI scanner, a synchronization solution has to be implemented (depending on the vendor of the MRI system). In contrast, we demonstrate a simple method for temporal synchronization, which does not require a connection to the MRI. It uses the normally undesired effect of induced voltages on the PET electronics from switching MRI gradients. The electronic circuit needs very few components and the gradient pick-up coils are made from PCB traces and vias on the PET detector boards. Neither programming the MRI nor any physical connection to the MR scanner is needed, thus avoiding electromagnetic compatibility problems. This method works inherently with most MRI sequences and is a vendor- independent solution. A characterization of the sensors in an MRI scanner showed that the MRI gradients are detected with a precision of 120 μs (with the current implementation). Using different trigger thresholds, it is possible to trigger selectively on certain MRI sequences, depending on their gradient slew rate settings. Timings and pulse diagrams of MRI sequences can be recognized from the generated data. The method was successfully used for temporal alignment between PET and MRI in an MRI-based PET-motion-compensation application.

The effect of switch control site on computer skills of infants and toddlers.

PubMed

Glickman, L; Deitz, J; Anson, D; Stewart, K

1996-01-01

The purpose of this study was to determine whether switch control site (hand vs. head) affects the age at which children can successfully activate a computer to play a cause-and-effect game. The sample consisted of 72 participants randomly divided into two groups (head switch and hand switch), with stratification for gender and age (9-11 months, 12-14 months, 15-17 months). All participants were typically developing. After a maximum of 5 min of training, each participant was given five opportunities to activate a Jelly Bean switch to play a computer game. Competency was defined as four to five successful switch activations. Most participants in the 9-month to 11-month age group could successfully use a hand switch to activate a computer, and for the 15-month to 17-month age group, 100% of the participants met with success. By contrast, in the head switch condition, approximately one third of the participants in each of the three age ranges were successful in activating the computer to play a cause-and-effect game. The findings from this study provide developmental guidelines for using switches (head vs. hand) to activate computers to play cause-and-effect games and suggest that the clinician may consider introducing basic computer and switch skills to children as young as 9 months of age. However, the clinician is cautioned that the head switch may be more difficult to master than the hand switch and that additional research involving children with motor impairments is needed.

Making electronic prescribing alerts more effective: scenario-based experimental study in junior doctors

PubMed Central

Shah, Priya; Wyatt, Jeremy C; Makubate, Boikanyo; Cross, Frank W

2011-01-01

Objective Expert authorities recommend clinical decision support systems to reduce prescribing error rates, yet large numbers of insignificant on-screen alerts presented in modal dialog boxes persistently interrupt clinicians, limiting the effectiveness of these systems. This study compared the impact of modal and non-modal electronic (e-) prescribing alerts on prescribing error rates, to help inform the design of clinical decision support systems. Design A randomized study of 24 junior doctors each performing 30 simulated prescribing tasks in random order with a prototype e-prescribing system. Using a within-participant design, doctors were randomized to be shown one of three types of e-prescribing alert (modal, non-modal, no alert) during each prescribing task. Measurements The main outcome measure was prescribing error rate. Structured interviews were performed to elicit participants' preferences for the prescribing alerts and their views on clinical decision support systems. Results Participants exposed to modal alerts were 11.6 times less likely to make a prescribing error than those not shown an alert (OR 11.56, 95% CI 6.00 to 22.26). Those shown a non-modal alert were 3.2 times less likely to make a prescribing error (OR 3.18, 95% CI 1.91 to 5.30) than those not shown an alert. The error rate with non-modal alerts was 3.6 times higher than with modal alerts (95% CI 1.88 to 7.04). Conclusions Both kinds of e-prescribing alerts significantly reduced prescribing error rates, but modal alerts were over three times more effective than non-modal alerts. This study provides new evidence about the relative effects of modal and non-modal alerts on prescribing outcomes. PMID:21836158

Parasitic resistive switching uncovered from complementary resistive switching in single active-layer oxide memory device

NASA Astrophysics Data System (ADS)

Zhu, Lisha; Hu, Wei; Gao, Chao; Guo, Yongcai

2017-12-01

This paper reports the reversible transition processes between the bipolar and complementary resistive switching (CRS) characteristics on the binary metal-oxide resistive memory devices of Pt/HfO x /TiN and Pt/TaO x /TiN by applying the appropriate bias voltages. More interestingly, by controlling the amplitude of the negative bias, the parasitic resistive switching effect exhibiting repeatable switching behavior is uncovered from the CRS behavior. The electrical observation of the parasitic resistive switching effect can be explained by the controlled size of the conductive filament. This work confirms the transformation and interrelationship among the bipolar, parasitic, and CRS effects, and thus provides new insight into the understanding of the physical mechanism of the binary metal-oxide resistive switching memory devices.

Influence of auditory spatial attention on cross-modal semantic priming effect: evidence from N400 effect.

PubMed

Wang, Hongyan; Zhang, Gaoyan; Liu, Baolin

2017-01-01

Semantic priming is an important research topic in the field of cognitive neuroscience. Previous studies have shown that the uni-modal semantic priming effect can be modulated by attention. However, the influence of attention on cross-modal semantic priming is unclear. To investigate this issue, the present study combined a cross-modal semantic priming paradigm with an auditory spatial attention paradigm, presenting the visual pictures as the prime stimuli and the semantically related or unrelated sounds as the target stimuli. Event-related potentials results showed that when the target sound was attended to, the N400 effect was evoked. The N400 effect was also observed when the target sound was not attended to, demonstrating that the cross-modal semantic priming effect persists even though the target stimulus is not focused on. Further analyses revealed that the N400 effect evoked by the unattended sound was significantly lower than the effect evoked by the attended sound. This contrast provides new evidence that the cross-modal semantic priming effect can be modulated by attention.

In their own words: Content analysis of pathways to recovery among individuals with the lived experience of homelessness and alcohol use disorders.

PubMed

Collins, Susan E; Jones, Connor B; Hoffmann, Gail; Nelson, Lonnie A; Hawes, Starlyn M; Grazioli, Véronique S; Mackelprang, Jessica L; Holttum, Jessica; Kaese, Greta; Lenert, James; Herndon, Patrick; Clifasefi, Seema L

2016-01-01

Alcohol use disorders (AUDs) are more prevalent among homeless individuals than in the general population, and homeless individuals are disproportionately affected by alcohol-related morbidity and mortality. Unfortunately, abstinence-based approaches are neither desirable to nor highly effective for most members of this population. Recent research has indicated that homeless people aspire to clinically significant recovery goals beyond alcohol abstinence, including alcohol harm reduction and quality-of-life improvement. However, no research has documented this population's preferred pathways toward self-defined recovery. Considering principles of patient-centred care, a richer understanding of this population's desired pathways to recovery may help providers better engage and support them. Participants (N=50) had lived experience of homelessness and AUDs and participated in semi-structured interviews regarding histories of homelessness, alcohol use, and abstinence-based treatment as well as suggestions for improving alcohol treatment. Conventional content analysis was used to ascertain participants' perceptions of abstinence-based treatment and mutual-help modalities, while it additionally revealed alternative pathways to recovery. Most participants reported involvement in abstinence-based modalities for reasons other than the goal of achieving long-term abstinence from alcohol (e.g., having shelter in winter months, "taking a break" from alcohol use, being among "like-minded people"). In contrast, most participants preferred alternative pathways to recovery, including fulfilling basic needs (e.g., obtaining housing), using harm reduction approaches (e.g., switching from higher to lower alcohol content beverages), engaging in meaningful activities (e.g., art, outings, spiritual/cultural activities), and making positive social connections. Most people with the lived experience of homelessness and AUDs we interviewed were uninterested in abstinence-based modalities as a means of attaining long-term alcohol abstinence. These individuals do, however, have creative ideas about alternative pathways to recovery that treatment providers may support to reduce alcohol-related harm and enhance quality of life. Copyright © 2015 Elsevier B.V. All rights reserved.

In their own words: Content analysis of pathways to recovery among individuals with the lived experience of homelessness and alcohol use disorders

PubMed Central

Collins, Susan E.; Jones, Connor B.; Hoffmann, Gail; Nelson, Lonnie A.; Hawes, Starlyn M.; Grazioli, Véronique S.; Mackelprang, Jessica L.; Holttum, Jessica; Kaese, Greta; Lenert, James; Herndon, Patrick; Clifasefi, Seema L.

2015-01-01

Background Alcohol use disorders (AUDs) are more prevalent among homeless individuals than in the general population, and homeless individuals are disproportionately affected by alcohol-related morbidity and mortality. Unfortunately, abstinence-based approaches are neither desirable to nor highly effective for most members of this population. Recent research has indicated that homeless people aspire to clinically significant recovery goals beyond alcohol abstinence, including alcohol harm reduction and quality-of-life improvement. However, no research has documented this population’s preferred pathways toward self-defined recovery. Considering principles of patient-centred care, a richer understanding of this population’s desired pathways to recovery may help providers better engage and support them. Methods Participants (N = 50) had lived experience of homelessness and AUDs and participated in semi-structured interviews regarding histories of homelessness, alcohol use, and abstinence-based treatment as well as suggestions for improving alcohol treatment. Conventional content analysis was used to ascertain participants’ perceptions of abstinence-based treatment and mutual-help modalities, while it additionally revealed alternative pathways to recovery. Results Most participants reported involvement in abstinence-based modalities for reasons other than the goal of achieving long-term abstinence from alcohol (e.g., having shelter in winter months, “taking a break” from alcohol use, being among “like-minded people”). In contrast, most participants preferred alternative pathways to recovery, including fulfilling basic needs (e.g., obtaining housing), using harm reduction approaches (e.g., switching from higher to lower alcohol content beverages), engaging in meaningful activities (e.g., art, outings, spiritual/cultural activities), and making positive social connections. Conclusions Most people with the lived experience of homelessness and AUDs we interviewed were uninterested in abstinence-based modalities as a means of attaining long-term alcohol abstinence. These individuals do, however, have creative ideas about alternative pathways to recovery that treatment providers may support to reduce alcohol-related harm and enhance quality of life. PMID:26364078

Effects of Dual-Task Management and Resistance Training on Gait Performance in Older Individuals: A Randomized Controlled Trial.

PubMed

Wollesen, Bettina; Mattes, Klaus; Schulz, Sören; Bischoff, Laura L; Seydell, L; Bell, Jeffrey W; von Duvillard, Serge P

2017-01-01

Background: Dual-task (DT) training is a well-accepted modality for fall prevention in older adults. DT training should include task-managing strategies such as task switching or task prioritization to improve gait performance under DT conditions. Methods: We conducted a randomized controlled trial to evaluate a balance and task managing training (BDT group) in gait performance compared to a single task (ST) strength and resistance training and a control group, which received no training. A total of 78 older individuals (72.0 ± 4.9 years) participated in this study. The DT group performed task managing training incorporating balance and coordination tasks while the ST group performed resistance training only. Training consisted of 12 weekly sessions, 60 min each, for 12 weeks. We assessed the effects of ST and BDT training on walking performance under ST and DT conditions in independent living elderly adults. ST and DT walking (visual verbal Stroop task) were measured utilizing a treadmill at self-selected walking speed (mean for all groups: 4.4 ± 1 km h -1 ). Specific gait variables, cognitive performance, and fear of falling were compared between all groups. > Results: Training improved gait performance for step length ( p < 0.001) and gait-line (ST: p < 0.01; DT p < 0.05) in both training groups. The BDT training group showed greater improvements in step length ( p < 0.001) and gait-line ( p < 0.01) during DT walking but did not have changes in cognitive performance. Both interventions reduced fear of falling ( p < 0.05). Conclusion: Implementation of task management strategies into balance and strength training in our population revealed a promising modality to prevent falls in older individuals. Trial registration: German register of clinical trials DRKS00012382.

Software-defined networking control plane for seamless integration of multiple silicon photonic switches in Datacom networks.

PubMed

Shen, Yiwen; Hattink, Maarten H N; Samadi, Payman; Cheng, Qixiang; Hu, Ziyiz; Gazman, Alexander; Bergman, Keren

2018-04-16

Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. We present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly network testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 µs control plane latency for data-center and high performance computing platforms.

Chitosan-Gated Magnetic-Responsive Nanocarrier for Dual-Modal Optical Imaging, Switchable Drug Release, and Synergistic Therapy

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

Wang, Hui; Mu, Qingxin; Revia, Richard

In this study, we present a multifunctional yet structurally simple nanocarrier that has a high drug loading capacity, releases drug in response to onset of an AC magnetic field, and can serve as a long-term imaging contrast agent and effectively kills cancer cells by synergistic action. This nanocarrier (HMMC-NC) has a spherical shell structure with a center cavity of 80 nm in diameter. The shell is comprised of two layers: an inner layer of magnetite that exhibits superparamagnetism and an outer layer of mesoporous carbon embedded with carbon dots that exhibit photoluminescence property. Thus in addition to being a drugmore » carrier, HMMC-NC is also a contrast agent for bioimaging. The switchable drug release is enabled by the chitosan molecules attached on the nanocarrier as the switching material which turns on or off the drug release in response to the application or withdrawal of an AC magnetic field.« less

DMD-based LED-illumination super-resolution and optical sectioning microscopy.

PubMed

Dan, Dan; Lei, Ming; Yao, Baoli; Wang, Wen; Winterhalder, Martin; Zumbusch, Andreas; Qi, Yujiao; Xia, Liang; Yan, Shaohui; Yang, Yanlong; Gao, Peng; Ye, Tong; Zhao, Wei

2013-01-01

Super-resolution three-dimensional (3D) optical microscopy has incomparable advantages over other high-resolution microscopic technologies, such as electron microscopy and atomic force microscopy, in the study of biological molecules, pathways and events in live cells and tissues. We present a novel approach of structured illumination microscopy (SIM) by using a digital micromirror device (DMD) for fringe projection and a low-coherence LED light for illumination. The lateral resolution of 90 nm and the optical sectioning depth of 120 μm were achieved. The maximum acquisition speed for 3D imaging in the optical sectioning mode was 1.6×10(7) pixels/second, which was mainly limited by the sensitivity and speed of the CCD camera. In contrast to other SIM techniques, the DMD-based LED-illumination SIM is cost-effective, ease of multi-wavelength switchable and speckle-noise-free. The 2D super-resolution and 3D optical sectioning modalities can be easily switched and applied to either fluorescent or non-fluorescent specimens.

DMD-based LED-illumination Super-resolution and optical sectioning microscopy

PubMed Central

Dan, Dan; Lei, Ming; Yao, Baoli; Wang, Wen; Winterhalder, Martin; Zumbusch, Andreas; Qi, Yujiao; Xia, Liang; Yan, Shaohui; Yang, Yanlong; Gao, Peng; Ye, Tong; Zhao, Wei

2013-01-01

Super-resolution three-dimensional (3D) optical microscopy has incomparable advantages over other high-resolution microscopic technologies, such as electron microscopy and atomic force microscopy, in the study of biological molecules, pathways and events in live cells and tissues. We present a novel approach of structured illumination microscopy (SIM) by using a digital micromirror device (DMD) for fringe projection and a low-coherence LED light for illumination. The lateral resolution of 90 nm and the optical sectioning depth of 120 μm were achieved. The maximum acquisition speed for 3D imaging in the optical sectioning mode was 1.6×107 pixels/second, which was mainly limited by the sensitivity and speed of the CCD camera. In contrast to other SIM techniques, the DMD-based LED-illumination SIM is cost-effective, ease of multi-wavelength switchable and speckle-noise-free. The 2D super-resolution and 3D optical sectioning modalities can be easily switched and applied to either fluorescent or non-fluorescent specimens. PMID:23346373

Sirolimus for the Treatment of a Massive Capillary-Lymphatico-Venous Malformation: A Case Report.

PubMed

Vlahovic, Aleksandar M; Vlahovic, Natasa S; Haxhija, Emir Q

2015-08-01

Management of patients with complex vascular anomalies (VAs) is often associated with significant morbidity and mortality because of the lack of effective treatment modalities that may lead to significant improvement of the disease and/or healing. Recently, reports of treatment of patients with complex VAs with sirolimus revealed encouraging results. Sirolimus inhibits the mammalian target of rapamycin, which acts as a master switch of numerous cellular processes. We report a successful use of sirolimus for the treatment of a patient with a complex CLVM of the trunk and the right lower extremity believed to be untreatable. Our patient had 44 hospitalizations during the 10-year period, with various unsuccessful treatments and continuous deterioration of his clinical condition, ending up in a wheelchair. His condition reversed to normal everyday activities 9 months after initiation of sirolimus therapy. We conclude that sirolimus is a very promising therapeutic option for children with complex VAs of capillary-lymphatico-venous type. Copyright © 2015 by the American Academy of Pediatrics.

Sequential Effects in Deduction: Cost of Inference Switch

ERIC Educational Resources Information Center

Milan, Emilio G.; Moreno-Rios, Sergio; Espino, Orlando; Santamaria, Carlos; Gonzalez-Hernandez, Antonio

2010-01-01

The task-switch paradigm has helped psychologists gain insight into the processes involved in changing from one activity to another. The literature has yielded consistent results about switch cost reconfiguration (abrupt offset in regular task-switch vs. gradual reduction in random task-switch; endogenous and exogenous components of switch cost;…

Effect of Inert Gas Switching at Depth on Decompression Outcome in Rats

DTIC Science & Technology

1989-01-01

Indcuae Security Classification) Effect Of inert gas switching at depth on decompression outcome in rats Liil RVRcCall1urn M~E 16. SUPPLEMENTARY...CLASSIrICATrIONOF TI PAGE All other edition% -ate obsfee UNCLASSIFIED Effect of inert gas switching at depth on decompression outcome in rats R. S... Effect of inert gas Although various models of inert gas transport in the switching at depth on decompression outcome in rats. J. Appl

Hybrid wavefront sensor for the fast detection of wavefront disturbances.

PubMed

Dong, Shihao; Haist, Tobias; Osten, Wolfgang

2012-09-01

Strongly aberrated wavefronts lead to inaccuracies and nonlinearities in holography-based modal wavefront sensing (HMWS). In this contribution, a low-resolution Shack-Hartmann sensor (LRSHS) is incorporated into HMWS via a compact holographic design to extend the dynamic range of HMWS. A static binary-phase computer-generated hologram is employed to generate the desired patterns for Shack-Hartmann sensing and HMWS. The low-order aberration modes dominating the wavefront error are first sensed with the LRSHS and corrected by the wavefront modulator. The system then switches to HMWS to obtain better sensor sensitivity and accuracy. Simulated as well as experimental results are shown for validating the proposed method.

New shielding configurations for a simultaneous PET/MRI scanner at 7T

PubMed Central

Peng, Bo J.; Wu, Yibao; Cherry, Simon R.; Walton, Jeffrey H.

2014-01-01

Understanding sources of electromagnetic interference are important in designing any electronic system. This is especially true when combining positron emission tomography (PET) and magnetic resonance imaging (MRI) in a multimodality system as coupling between the subsystems can degrade the performance of either modality. For this reason, eliminating radio frequency (RF) interference and gradient-induced eddy currents have been major challenges in building simultaneous hybrid PET/MRI systems. MRI requires negligible RF interference at the Larmor resonance frequency, while RF interference at almost any frequency may corrupt PET data. Moreover, any scheme that minimizes these interactions would, ideally, not compromise the performance of either subsystem. This paper lays out a plan to resolve these problems. A carbon fiber composite material is found to be a good RF shield at the Larmor frequency (300 MHz in this work) while introducing negligible gradient eddy currents. This carbon fiber composite also provides excellent structural support for the PET detector components. Low frequency electromagnetic radiation (81 kHz here) from the switching power supplies of the gradient amplifiers was also found to interfere with the PET detector. Placing the PET detector module between two carbon fiber tubes and grounding the inner carbon fiber tube to the PET detector module ground reduced this interference. Further reductions were achieved by adding thin copper (Cu) foil on the outer carbon fiber case and electrically grounding the PET detector module so that all 3 components had a common ground, i.e. with the PET detector in an electrostatic cage. Finally, gradient switching typical in MRI sequences can result in count losses in the particular PET detector design studied. Moreover, the magnitude of this effect depends on the location of the detector within the magnet bore and which MRI gradient is being switched. These findings have a bearing on future designs of PET/MRI systems. PMID:24380812

Reconfiguration of the multiwavelength operation of optical fiber ring lasers by the modifiable intra-cavity induced losses of an in-fiber tip probe modal Michelson interferometer

NASA Astrophysics Data System (ADS)

Salceda-Delgado, G.; Martinez-Rios, A.; Sierra-Hernandez, J. M.; Rodríguez-Carreón, V. C.; Toral-Acosta, D.; Selvas-Aguilar, R.; Álvarez-Tamayo, R. I.; Castillo-Guzman, A. A.; Rojas-Laguna, R.

2018-03-01

A straightforward and versatile method for switching from single to different multiwavelength laser emission in ring cavity fiber lasers is proposed and demonstrated experimentally. The method is based on using the changeable interference pattern from an optical fiber modal Michelson interferometer as a wavelength selective filter into the ring cavity laser. The interferometer is constructed using a bi-conical tapered fiber and a single-mode fiber segment, with these being spliced together to form an optical fiber tip probe. When the length of the single-mode fiber piece is modified, the phase difference between the interfering modes of the interferometer causes a change in the interferometer free spectral range. As a consequence, the laser intra-cavity losses lead to gain competition, which allows us to adjust the number of simultaneously generated laser lines. A multiwavelength reconfiguration of the laser from one up to a maximum of eight emission lines was obtained, with a maximum SNR of around 47 dBm.

Modal sound transmission loss of a single leaf panel: Asymptotic solutions.

PubMed

Wang, Chong

2015-12-01

In a previously published paper [C. Wang, J. Acoust. Soc. Am. 137(6), 3514-3522 (2015)], the modal sound transmission coefficients of a single leaf panel were discussed with regard to the inter-modal coupling effects. By incorporating such effect into the equivalent modal radiation impedance, which is directly related to the modal sound transmission coefficient of each mode, the overall sound transmission loss for both normal and randomized sound incidences was computed through a simple modal superposition. Benefiting from the analytical expressions of the equivalent modal impedance and modal transmission coefficients, in this paper, behaviors of modal sound transmission coefficients in several typical frequency ranges are discussed in detail. Asymptotic solutions are also given for the panels with relatively low bending stiffnesses, for which the sound transmission loss has been assumed to follow the mass law of a limp panel. Results are also compared to numerical analysis and the renowned mass law theories.

H∞ control for switched fuzzy systems via dynamic output feedback: Hybrid and switched approaches

NASA Astrophysics Data System (ADS)

Xiang, Weiming; Xiao, Jian; Iqbal, Muhammad Naveed

2013-06-01

Fuzzy T-S model has been proven to be a practical and effective way to deal with the analysis and synthesis problems for complex nonlinear systems. As for switched nonlinear system, describing its subsystems as fuzzy T-S models, namely switched fuzzy system, naturally is an alternative method to conventional control approaches. In this paper, the H∞ control problem for a class of switched fuzzy systems is addressed. Hybrid and switched design approaches are proposed with different availability of switching signal information at switching instant. The hybrid control strategy includes two parts: fuzzy controllers for subsystems and state updating controller at switching instant, and the switched control strategy contains the controllers for subsystems. It is demonstrated that the conservativeness is reduced by introducing the state updating behavior but its cost is an online prediction of switching signal. Numerical examples are given to illustrate the effectiveness of proposed approaches and compare the conservativeness of two approaches.

Cueing cognitive flexibility: Item-specific learning of switch readiness.

PubMed

Chiu, Yu-Chin; Egner, Tobias

2017-12-01

The rich behavioral repertoire of the human species derives from our ability to flexibly reconfigure processing strategies (task sets) in response to changing requirements. This updating of task sets is effortful, as reflected by longer response times when switching a task than repeating it (switch costs). However, some recent data suggest that switch costs can be reduced by cueing switch readiness bottom-up, by associating particular stimuli with frequent switch requirements. This type of "stimulus-control (S-C) learning" would be highly adaptive, as it combines the speed of automatic (bottom-up) processing with the flexibility and generalizability of controlled (top-down) processing. However, it is unclear whether S-C learning of switch readiness is truly possible, and what the underlying mechanisms are. Here we address these questions by pairing specific stimuli with a need to update task-sets either frequently or rarely. In all 3 experiments, we observe robust item-specific switch probability (ISSP) effects as revealed by smaller switch costs for frequent switch items than for rare switch items. By including a neutral condition, we also show that the ISSP effect is primarily driven by S-C learning reducing switch costs in frequent switch items. Furthermore, by employing 3 tasks in Experiment 3, we establish that the ISSP effect reflects an enhancement of general switch readiness, rather than of the readiness to switch to a specific alternate task. These results firmly establish that switch readiness is malleable by item-specific S-C learning processes, documenting that a generalizable state of cognitive flexibility can be primed by a bottom-up stimulus. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Cross-modal links among vision, audition, and touch in complex environments.

PubMed

Ferris, Thomas K; Sarter, Nadine B

2008-02-01

This study sought to determine whether performance effects of cross-modal spatial links that were observed in earlier laboratory studies scale to more complex environments and need to be considered in multimodal interface design. It also revisits the unresolved issue of cross-modal cuing asymmetries. Previous laboratory studies employing simple cues, tasks, and/or targets have demonstrated that the efficiency of processing visual, auditory, and tactile stimuli is affected by the modality, lateralization, and timing of surrounding cues. Very few studies have investigated these cross-modal constraints in the context of more complex environments to determine whether they scale and how complexity affects the nature of cross-modal cuing asymmetries. Amicroworld simulation of battlefield operations with a complex task set and meaningful visual, auditory, and tactile stimuli was used to investigate cuing effects for all cross-modal pairings. Significant asymmetric performance effects of cross-modal spatial links were observed. Auditory cues shortened response latencies for collocated visual targets but visual cues did not do the same for collocated auditory targets. Responses to contralateral (rather than ipsilateral) targets were faster for tactually cued auditory targets and each visual-tactile cue-target combination, suggesting an inhibition-of-return effect. The spatial relationships between multimodal cues and targets significantly affect target response times in complex environments. The performance effects of cross-modal links and the observed cross-modal cuing asymmetries need to be examined in more detail and considered in future interface design. The findings from this study have implications for the design of multimodal and adaptive interfaces and for supporting attention management in complex, data-rich domains.

A new account of the effect of probability on task switching: ERP evidence following the manipulation of switch probability, cue informativeness and predictability

PubMed Central

Nessler, Doreen; Friedman, David; Johnson, Ray

2012-01-01

This task-switching ERP study of 16 young participants investigated whether increased RT slowing on stay trials and faster RTs on switch trials for frequent than infrequent switching are explained by an activation or preparation account. The activation account proposes that task sets are maintained at a higher baseline activation level for frequent switching, necessitating increased task-set updating, as reflected by a larger and/or longer lasting early parietal positivity. The preparation account assumes advance (pre-cue) switch preparation (i.e., task-set reconfiguration), preceding stay and switch trials for frequent switching, as reflected by pre-cue and post-cue late parietal positivities. By and large, the data support the activation account. However, we also found increased, pre-cue task-set updating on frequent stay trials and pre-cue, task-set reconfiguration prior to predictable, frequent switches. These results lead us to propose an extended activation account to explain the effects of switch probability on the executive processes underlying task-switching behavior. PMID:22820040

Teaching communication skills to hospice teams: comparing the effectiveness of a communication skills laboratory with in-person, second life, and phone role-playing.

PubMed

Hamilton, Gillian; Ortega, Rosio; Hochstetler, Vicki; Pierson, Kristen; Lin, Peiyi; Lowes, Susan

2014-09-01

Communication skills are critical in hospice care but challenging to teach. Therefore, a hospice agency developed a communication skills laboratory for nurses and social workers. Learners role-played 3 common hospice scenarios. The role-play modalities were in-person, Second Life, and telephone. Learners were scored on 4 communication aspects. Learners in all modalities rated the laboratory as very effective. However, learners in the Second Life and phone modality showed greater improvements from scene 1 to 3 than those in the in-person modality. There were no significant differences in improvement between the Second Life and phone modalities. Results support the effectiveness of this communication skills laboratory while using different teaching modalities and show phone and Second Life role-plays were more effective than an in-person role-play. © The Author(s) 2013.

Overcoming residual interference in mental set switching: Neural correlates and developmental trajectory

PubMed Central

Witt, Suzanne T.; Stevens, Michael C.

2012-01-01

Mental set switching is a key facet of executive control measured behaviorally through reaction time or accuracy (i.e., ‘switch costs’) when shifting among task types. One of several experimentally-dissociable influences on switch costs is ‘task set inertia’, conceptualized as the residual interference conferred when a previous stimulus-response tendency interferes with subsequent stimulus processing on a new task. Task set inertia is thought to represent the passive decay of the previous stimulus-response set from working memory, and its effects decrease with increased interstimulus interval. Closely spaced trials confer high task set inertia, while sparsely spaced trials confer low task set inertia. This functional magnetic resonance imaging (fMRI) study characterized, for the first time, two opposing brain systems engaged to resolve task set inertia: 1) a frontoparietal ‘cortical control’ network for overcoming high task set inertia interference and 2) a subcortical-motor network more active during trials with low task set inertia. These networks were distinct from brain regions showing general switching effects (i.e., switch > non-switch) and from other previously-characterized interference effects. Moreover, there were ongoing maturational effects throughout adolescence for the brain regions engaged to overcome high task set inertia not seen for generalized switching effects. These novel findings represent a new avenue of exploration of cognitive set switching neural function. PMID:22584223

Context Switch Effects on Acquisition and Extinction in Human Predictive Learning

ERIC Educational Resources Information Center

Rosas, Juan M.; Callejas-Aguilera, Jose E.

2006-01-01

Four experiments tested context switch effects on acquisition and extinction in human predictive learning. A context switch impaired probability judgments about a cue-outcome relationship when the cue was trained in a context in which a different cue underwent extinction. The context switch also impaired judgments about a cue trained in a context…

Effects of Parasitic Reactance on Lattice Circuit Slotline Switch

NASA Technical Reports Server (NTRS)

Ponchak, George E.

2016-01-01

A slotline lattice switch has recently been proposed and demonstrated. In that paper, ideal diode characteristics were assumed. In this paper, the effects of parasitic reactances, due to the diode and the wire bonds that connect it to the circuit, are investigated. The switch is compared to a traditional slotline switch with a single diode across the slot.

Modality effects in Second Life: the mediating role of social presence and the moderating role of product involvement.

PubMed

Jin, Seung-A Annie

2009-12-01

The rapid growth of virtual worlds is one of the most recent Internet trends. Some distinguishing features of virtual environments include the employment of avatars and multimodal communication among avatars. This study examined the effects of the modality (text vs. audio) of message presentation on people's evaluation of spokes-avatar credibility and the informational value of promotional messages in avatar-based advertising inside 3D virtual environments. An experiment was conducted in the virtual Apple retail store inside Second Life, the most popular and fastest growing virtual world. The author designed a two-group (textual advertisement vs. auditory advertisement) comparison experiment by manipulating the modality of conveying advertisement messages. The author also created a spokes-avatar that represents a real-life organization (Apple) and presents promotional messages about its innovative product, the iPhone. Data analyses showed that (a) textual modality (vs. auditory modality) resulted in greater source expertise, informational value of the advertisement message, and social presence; and that (b) high product involvement (vs. low product involvement) resulted in a more positive attitude toward the product, higher buying intention, and a higher level of perceived interactivity. In addition to the main effects of product involvement and modality, results showed significant interaction between involvement and modality. Modality effects were stronger for people with low product involvement than for those with high product involvement, thus confirming the moderating effects of product involvement. Results of a path analysis also showed that social presence mediated the effects of modality on the perceived informational value of the advertisement message.

Effect of walking and resting after three cryotherapy modalities on the recovery of sensory and motor nerve conduction velocity in healthy subjects.

PubMed

Herrera, Esperanza; Sandoval, Maria Cristina; Camargo, Diana M; Salvini, Tania F

2011-01-01

Different cryotherapy modalities have distinct effects on sensory and motor nerve conduction parameters. However, it is unclear how these parameters change during the post-cooling period and how the exercise carried out in this period would influence the recovery of nerve conduction velocity (NCV). To compare the effects of three cryotherapy modalities on post-cooling NCV and to analyze the effect of walking on the recovery of sensory and motor NCV. Thirty six healthy young subjects were randomly allocated into three groups: ice massage (n=12), ice pack (n=12) and cold water immersion (n=12). The modalities were applied to the right leg. The subjects of each modality group were again randomized to perform a post-cooling activity: a) 30 min rest, b) walking 15 min followed by 15 min rest. The NCV of sural (sensory) and posterior tibial (motor) nerves was evaluated. Initial (pre-cooling) and final (30 min post-cooling) NCV were compared using a paired t-test. The effects of the modalities and the post-cooling activities on NCV were evaluated by an analysis of covariance. The significance level was α=0.05. There was a significant difference between immersion and ice massage on final sensory NCV (p=0.009). Ice pack and ice massage showed similar effects (p>0.05). Walking accelerated the recovery of sensory and motor NCV, regardless of the modality previously applied (p<0.0001). Cold water immersion was the most effective modality for maintaining reduced sensory nerve conduction after cooling. Walking after cooling, with any of the three modalities, enhances the recovery of sensory and motor NCV.

Software-defined networking control plane for seamless integration of multiple silicon photonic switches in Datacom networks

DOE PAGES

Shen, Yiwen; Hattink, Maarten; Samadi, Payman; ...

2018-04-13

Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. Here, we present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly networkmore » testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 microsecond control plane latency for data-center and high performance computing platforms.« less

Software-defined networking control plane for seamless integration of multiple silicon photonic switches in Datacom networks

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

Shen, Yiwen; Hattink, Maarten; Samadi, Payman

Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. Here, we present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly networkmore » testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 microsecond control plane latency for data-center and high performance computing platforms.« less

Mindset switching increases the use of 'want-based' over 'should-based' behaviors

PubMed Central

Zhang, Nan-Nan; Xu, Dai-Xuan

2018-01-01

This study examines the consequences of mindset switching on behavioral choices in want/should conflicts. Building on the insights of the ego depletion literature, we propose that mindset switching depletes individuals’ self-control resources and therefore prompts the choice of want behavior, which provides immediate pleasure, over should behavior, which provides long-term utility. Four laboratory experiments with university students that stimulated individuals to switch mindsets were conducted to test our hypotheses. Experiment 1 demonstrated that switching between individualist and collectivist mindsets increased the subjects’ tendency to prefer popular magazines over scientific journals. Experiment 2 replicated the results by testing the relationship between an abstract/concrete mindset-switching task and want/should online behavioral choices. The mediating effect of ego depletion was also supported. Experiment 3 retested the main effect of language-switching on reading choices, and the mediating effect of ego-depletion. Experiment 3 also tested the moderating effect of the Need for Cognition, and eliminated the alternative explanation of cognitive fatigue. In Experiment 4, actual food choices were used as the direct measure of want/should behaviors to test the robustness of our findings. The results consistently supported our hypotheses that mindset switching has significant effects on behavioral choices in terms of overindulgence, such as increasing want behavior and thus foregoing should behavior. PMID:29709003

Shaving Bridges and Tuning Kitaraa: The Effect of Language Switching on Semantic Processing

PubMed Central

Hut, Suzanne C. A.; Leminen, Alina

2017-01-01

Language switching has been repeatedly found to be costly. Yet, there are reasons to believe that switches in language might benefit language comprehension in some groups of people, such as less proficient language learners. This study therefore investigated the interplay between language switching and semantic processing in groups with varying language proficiency. EEG was recorded while L2 learners of English with intermediate and high proficiency levels read semantically congruent or incongruent sentences in L2. Translations of congruent and incongruent target words were additionally presented in L1 to create intrasentential language switches. A control group of English native speakers was tested in order to compare responses to non-switched stimuli with those of L2 learners. An omnibus ANOVA including all groups revealed larger N400 responses for non-switched incongruent stimuli compared to congruent stimuli. Additionally, despite switches to L1 at target word position, semantic N400 responses were still elicited in both L2 learner groups. Further switching effects were reflected by an N400-like effect and a late positivity complex, pointing to possible parsing efforts after language switches. Our results therefore show that although language switches are associated with increased mental effort, switches may not necessarily be costly on the semantic level. This finding contributes to the ongoing discussion on language inhibition processes, and shows that, in these intermediate and high proficient L2 learners, semantic processes look similar to those of native speakers of English. PMID:28900402

Effectiveness of Psychotherapy in Personality Disorders Not Otherwise Specified: A Comparison of Different Treatment Modalities.

PubMed

Horn, Eva K; Bartak, Anna; Meerman, Anke M M A; Rossum, Bert V; Ziegler, Uli M; Thunnissen, Moniek; Soons, Mirjam; Andrea, Helene; Hamers, Elisabeth F M; Emmelkamp, Paul M G; Stijnen, Theo; Busschbach, Jan J V; Verheul, Roel

2015-01-01

Although personality disorder not otherwise specified (PDNOS) is highly prevalent and associated with a high burden of disease, only a few treatment studies in this patient group exist. This study is the first to investigate the effectiveness of different modalities of psychotherapy in patients with PDNOS, i.e., short-term (up to 6 months) and long-term (more than 6 months) outpatient, day hospital, and inpatient psychotherapy. A total of 205 patients with PDNOS were assigned to one of six treatment modalities. Effectiveness was assessed over 60 months after baseline. The primary outcome measure was symptom severity, and the secondary outcome measures included psychosocial functioning and quality of life. The study design was quasi-experimental, and the multiple propensity score was used to control for initial differences between treatment groups. All treatment modalities showed positive outcomes, especially in terms of improvements of symptom severity and social role functioning. At 12-month follow-up, after adjustment for initial differences between the treatment groups, short-term outpatient psychotherapy and short-term inpatient psychotherapy showed most improvement and generally outperformed the other modalities concerning symptom severity. At 60 months after baseline, effectiveness remained but observed differences between modalities mostly diminished. Patients with PDNOS benefit from psychotherapy both at short-term and long-term follow-up. Short-term outpatient psychotherapy and short-term inpatient psychotherapy seem to be superior to the other treatment modalities at 12-month follow-up. At 60-month follow-up, treatments showed mostly comparable effectiveness. The effectiveness of different modalities of psychotherapy in patients with PDNOS (i.e., short-term vs long-term; outpatient versus day hospital versus inpatient psychotherapy) has not yet been compared. Different modalities of psychotherapy are effective for patients with PDNOS, and positive effects remain after 5 years. In patients with PDNOS short-term (less than 6 months) outpatient psychotherapy and short-term inpatient psychotherapy seem to be superior to the four other treatment modalities at 12-month follow-up. At 60-month follow-up, treatments showed mostly comparable effectiveness. Copyright © 2014 John Wiley & Sons, Ltd.

The effect of pain on task switching: pain reduces accuracy and increases reaction times across multiple switching paradigms.

PubMed

Attridge, Nina; Keogh, Edmund; Eccleston, Christopher

2016-10-01

Pain disrupts attention, which may have negative consequences for daily life for people with acute or chronic pain. It has been suggested that switching between tasks may leave us particularly susceptible to pain-related attentional disruption, because we need to disengage our attention from one task before shifting it onto another. Switching tasks typically elicit lower accuracies and/or longer reaction times when participants switch to a new task compared with repeating the same task, and pain may exacerbate this effect. We present 3 studies to test this hypothesis. In study 1, participants completed 2 versions of an alternating runs switching task under pain-free and thermal pain-induction conditions. Pain did not affect performance on either task. In studies 2 and 3, we examined 7 versions of the switching task using large general population samples, experiencing a variety of naturally occurring pain conditions, recruited and tested on the internet. On all tasks, participants with pain had longer reaction times on both switch and repeat trials compared with participants without pain, but pain did not increase switch costs. In studies 2 and 3, we also investigated the effects of type of pain, duration of pain, and analgesics on task performance. We conclude that pain has a small dampening effect on performance overall on switching tasks. This suggests that pain interrupts attention even when participants are engaged in a trial, not only when attention has been disengaged for shifting to a new task set.

Visual and Haptic Shape Processing in the Human Brain: Unisensory Processing, Multisensory Convergence, and Top-Down Influences.

PubMed

Lee Masson, Haemy; Bulthé, Jessica; Op de Beeck, Hans P; Wallraven, Christian

2016-08-01

Humans are highly adept at multisensory processing of object shape in both vision and touch. Previous studies have mostly focused on where visually perceived object-shape information can be decoded, with haptic shape processing receiving less attention. Here, we investigate visuo-haptic shape processing in the human brain using multivoxel correlation analyses. Importantly, we use tangible, parametrically defined novel objects as stimuli. Two groups of participants first performed either a visual or haptic similarity-judgment task. The resulting perceptual object-shape spaces were highly similar and matched the physical parameter space. In a subsequent fMRI experiment, objects were first compared within the learned modality and then in the other modality in a one-back task. When correlating neural similarity spaces with perceptual spaces, visually perceived shape was decoded well in the occipital lobe along with the ventral pathway, whereas haptically perceived shape information was mainly found in the parietal lobe, including frontal cortex. Interestingly, ventrolateral occipito-temporal cortex decoded shape in both modalities, highlighting this as an area capable of detailed visuo-haptic shape processing. Finally, we found haptic shape representations in early visual cortex (in the absence of visual input), when participants switched from visual to haptic exploration, suggesting top-down involvement of visual imagery on haptic shape processing. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

The Effects of Multimedia Content Design Modalities on Students' Motivation and Achievement in History

ERIC Educational Resources Information Center

Park, Sanghoon; Braud, Allison

2017-01-01

This study examined the effects of different multimedia design modalities on middle-school students' motivation and achievement in history and also sought to determine whether an interaction effect on achievement occurs between students' prior knowledge and the different multimedia design modalities. Two groups of eighth-grade students enrolled in…

Does the Modality Effect Exist? And if so, Which Modality Effect?

ERIC Educational Resources Information Center

Reinwein, Joachim

2012-01-01

The modality effect is a central issue in multimedia learning [see Mayer (Cambridge University Press, 2005a), for a review]. Sweller's Cognitive Load Theory (CLT), for example, presumes that an illustrated text is better understood when presented visually rather than orally. The predictive power of CLT lies in how it links in to Baddeley's (1986)…

Effects of Text Modality in Multimedia Presentations on Written and Oral Performance

ERIC Educational Resources Information Center

Broek, G. S. E.; Segers, E.; Verhoeven, L.

2014-01-01

A common assumption in multimedia design is that audio-visual materials with pictures and spoken narrations lead to better learning outcomes than visual-only materials with pictures and on-screen text. The present study questions the generalizability of this modality effect. We explored how modality effects change over time, taking into account…

Common Modality Effects in Immediate Free Recall and Immediate Serial Recall

ERIC Educational Resources Information Center

Grenfell-Essam, Rachel; Ward, Geoff; Tan, Lydia

2017-01-01

In 2 experiments, participants were presented with lists of between 2 and 12 words for either immediate free recall (IFR) or immediate serial recall (ISR). Auditory recall advantages at the end of the list (modality effects) and visual recall advantages early in the list (inverse modality effects) were observed in both tasks and the extent and…

Cue-Independent Task-Specific Representations in Task Switching: Evidence from Backward Inhibition

ERIC Educational Resources Information Center

Altmann, Erik M.

2007-01-01

The compound-cue model of cognitive control in task switching explains switch cost in terms of a switch of task cues rather than of a switch of tasks. The present study asked whether the model generalizes to Lag 2 repetition cost (also known as backward inhibition), a related effect in which the switch from B to A in ABA task sequences is costlier…

The extent of cigarette brand and company switching: results from the Adult Use-of-Tobacco Survey.

PubMed

Siegel, M; Nelson, D E; Peddicord, J P; Merritt, R K; Giovino, G A; Eriksen, M P

1996-01-01

To evaluate the effects of cigarette advertising on brand switching, an accurate estimate of the extent of cigarette brand and company switching among current smokers is needed. Data from the 1986 Adult Use-of-Tobacco Survey were analyzed to estimate the percentage of adult smokers who switched cigarette brands and companies in the previous year. Approximately 9.2% of adult smokers (4.2 million) switched cigarette brands in 1986, and 6.7% (3.1 million) switched cigarette companies. The aggregate profitability of brand switching in 1986 was approximately $362 million. Based on this analysis, brand switching alone justifies only a small percentage of a cigarette company's advertising and promotion expenditures, suggesting that future research should address other potential effects of advertising, including maintenance of brand loyalty and expanding the cigarette market. Medical Subject Headings (MeSH): addictive behavior, advertising, smoking, tobacco.

Controllability of multi-agent systems with periodically switching topologies and switching leaders

NASA Astrophysics Data System (ADS)

Tian, Lingling; Zhao, Bin; Wang, Long

2018-05-01

This paper considers controllability of multi-agent systems with periodically switching topologies and switching leaders. The concept of m-periodic controllability is proposed, and a criterion for m-periodic controllability is established. The effect of the duration of subsystems on controllability is analysed by utilising a property of analytic functions. In addition, the influence of switching periods on controllability is investigated, and an algorithm is proposed to search for the fewest periods to ensure controllability. A necessary condition for m-periodic controllability is obtained from the perspective of eigenvectors of the subsystems' Laplacian matrices. For a system with switching leaders, it is proved that switching-leader controllability is equivalent to multiple-leader controllability. Furthermore, both the switching order and the tenure of agents being leaders have no effect on the controllability. Some examples are provided to illustrate the theoretical results.

An energy-consistent fracture model for ferroelectrics

NASA Astrophysics Data System (ADS)

Miao, Hongchen; Li, Faxin

2017-02-01

The fracture behavior of ferroelectrics has been intensively studied in recent decades, though currently a widely accepted fracture mechanism is still lacking. In this work, enlightened by previous experimental observations that crack propagation in ferroelectrics is always accompanied by domain switching, we propose a micromechanical model in which both crack propagation and domain switching are controlled by energy-based criteria. Both electric energy and mechanical energy can induce domain switching, while only mechanical energy can drive crack propagation. Furthermore, constrained domain switching is considered in this model, leading to the gradient domain switching zone near the crack tip. Analysis results show that stress-induced ferroelastic switching always has a toughening effect as the mechanical energy release rate serves as the driving force for both fracture and domain switching. In comparison, the electric-field-induced switching may have either a toughening or detoughening effect. The proposed model can qualitatively agree with the existing experimental results.

Comparing the Effectiveness and Safety of the Addition of and Switching to Aripiprazole for Resolving Antipsychotic-Induced Hyperprolactinemia: A Multicenter, Open-Label, Prospective Study.

PubMed

Yoon, Hui Woo; Lee, Jung Suk; Park, Sang Jin; Lee, Seon-Koo; Choi, Won-Jung; Kim, Tae Yong; Hong, Chang Hyung; Seok, Jeong-Ho; Park, Il-Ho; Son, Sang Joon; Roh, Daeyoung; Kim, Bo-Ra; Lee, Byung Ook

Hyperprolactinemia is an important but often overlooked adverse effect of antipsychotics. Several studies have shown that switching to or adding aripiprazole normalizes antipsychotic-induced hyperprolactinemia. However, no study has directly compared the effectiveness and safety of the 2 strategies. A total of 52 patients with antipsychotic-induced hyperprolactinemia were recruited. Aripiprazole was administered to patients with mild hyperprolactinemia (serum prolactin level < 50 ng/mL). Patients with severe hyperprolactinemia (serum prolactin level > 50 ng/mL) were randomized to an aripiprazole-addition group (adding aripiprazole to previous antipsychotics) or a switching group (switching previous antipsychotics to aripiprazole). Serum prolactin level, menstrual disturbances, sexual dysfunction, psychopathologies, and quality of life were measured at weeks 0, 1, 2, 4, 6, and 8. Both the addition and switching groups showed significantly reduced serum prolactin level and menstrual disturbances and improved sexual dysfunction. In patients with severe hyperprolactinemia, the numbers of patients with hyperprolactinemia and menstrual disturbance in the switching group were significantly lower than those in the addition group at week 8. Both the addition and switching strategies were effective in resolving antipsychotic-induced hyperprolactinemia and hyperprolactinemia-related adverse events, including menstrual disturbances and sexual dysfunction. In addition, these findings suggest that switching to aripiprazole may be more effective than addition of aripiprazole for normalizing hyperprolactinemia and improving hyperprolactinemia-related adverse events in patients with schizophrenia.

Complementary resistive switching in BaTiO3/NiO bilayer with opposite switching polarities

NASA Astrophysics Data System (ADS)

Li, Shuo; Wei, Xianhua; Lei, Yao; Yuan, Xincai; Zeng, Huizhong

2016-12-01

Resistive switching behaviors have been investigated in the Au/BaTiO3/NiO/Pt structure by stacking the two elements with different switching types. The conducting atomic force microscope measurements on BaTiO3 thin films and NiO thin films suggest that with the same active resistive switching region, the switching polarities in the two semiconductors are opposite to each other. It is in agreement with the bipolar hysteresis I-V curves with opposite switching polarities for single-layer devices. The bilayer devices show complementary resistive switching (CRS) without electroforming and unipolar resistive switching (URS) after electroforming. The coexistence of CRS and URS is mainly ascribed to the co-effect of electric field and Joule heating mechanisms, indicating that changeable of resistance in this device is dominated by the redistribution of oxygen vacancies in BaTiO3 and the formation, disruption, restoration of conducting filaments in NiO. CRS in bilayer with opposite switching polarities is effective to solve the sneak current without the introduction of any selector elements or an additional metal electrode.

Shared Syntax in Language Production and Language Comprehension—An fMRI Study

PubMed Central

Menenti, Laura; Weber, Kirsten; Petersson, Karl Magnus; Hagoort, Peter

2012-01-01

During speaking and listening syntactic processing is a crucial step. It involves specifying syntactic relations between words in a sentence. If the production and comprehension modality share the neuronal substrate for syntactic processing then processing syntax in one modality should lead to adaptation effects in the other modality. In the present functional magnetic resonance imaging experiment, participants either overtly produced or heard descriptions of pictures. We looked for brain regions showing adaptation effects to the repetition of syntactic structures. In order to ensure that not just the same brain regions but also the same neuronal populations within these regions are involved in syntactic processing in speaking and listening, we compared syntactic adaptation effects within processing modalities (syntactic production-to-production and comprehension-to-comprehension priming) with syntactic adaptation effects between processing modalities (syntactic comprehension-to-production and production-to-comprehension priming). We found syntactic adaptation effects in left inferior frontal gyrus (Brodmann's area [BA] 45), left middle temporal gyrus (BA 21), and bilateral supplementary motor area (BA 6) which were equally strong within and between processing modalities. Thus, syntactic repetition facilitates syntactic processing in the brain within and across processing modalities to the same extent. We conclude that that the same neurobiological system seems to subserve syntactic processing in speaking and listening. PMID:21934094

MR-compatibility assessment of MADPET4: a study of interferences between an SiPM-based PET insert and a 7 T MRI system.

PubMed

Omidvari, Negar; Topping, Geoffrey; Cabello, Jorge; Paul, Stephan; Schwaiger, Markus; Ziegler, Sibylle I

2018-05-01

Compromises in the design of a positron emission tomography (PET) insert for a magnetic resonance imaging (MRI) system should minimize the deterioration of image quality in both modalities, particularly when simultaneous demanding acquisitions are performed. In this work, the advantages of using individually read-out crystals with high-gain silicon photomultipliers (SiPMs) were studied with a small animal PET insert for a 7 T MRI system, in which the SiPM charge was transferred to outside the MRI scanner using coaxial cables. The interferences between the two systems were studied with three radio-frequency (RF) coil configurations. The effects of PET on the static magnetic field, flip angle distribution, RF noise, and image quality of various MRI sequences (gradient echo, spin echo, and echo planar imaging (EPI) at 1 H frequency, and chemical shift imaging at 13 C frequency) were investigated. The effects of fast-switching gradient fields and RF pulses on PET count rate were studied, while the PET insert and the readout electronics were not shielded. Operating the insert inside a 1 H volume coil, used for RF transmission and reception, limited the MRI to T1-weighted imaging, due to coil detuning and RF attenuation, and resulted in significant PET count loss. Using a surface receive coil allowed all tested MR sequences to be used with the insert, with 45-59% signal-to-noise ratio (SNR) degradation, compared to without PET. With a 1 H/ 13 C volume coil inside the insert and shielded by a copper tube, the SNR degradation was limited to 23-30% with all tested sequences. The insert did not introduce any discernible distortions into images of two tested EPI sequences. Use of truncated sinc shaped RF excitation pulses and gradient field switching had negligible effects on PET count rate. However, PET count rate was substantially affected by high-power RF block pulses and temperature variations due to high gradient duty cycles.

Effect of CpG dinucleotides within IgH switch region repeats on immunoglobulin class switch recombination.

PubMed

Zhang, Zheng Z; Hsieh, Chih-Lin; Okitsu, Cindy Yen; Han, Li; Yu, Kefei; Lieber, Michael R

2015-08-01

Immunoglobulin (Ig) heavy chains undergo class switch recombination (CSR) to change the heavy chain isotype from IgM to IgG, A or E. The switch regions are several kilobases long, repetitive, and G-rich on the nontemplate strand. They are also relatively depleted of CpG (also called CG) sites for unknown reasons. Here we use synthetic switch regions at the IgH switch alpha (Sα) locus to test the effect of CpG sites and to try to understand why the IgH switch sequences evolved to be relatively depleted of CpG. We find that even just two CpG sites within an 80 bp synthetic switch repeat iterated 15 times (total switch region length of 1200 bp containing 30 CpG sites) are sufficient to dramatically reduce both Ig CSR and transcription through the switch region from the upstream Iα sterile transcript promoter, which is the promoter that directs transcripts through the Sα region. De novo DNA methylation occurs at the four CpG sites in and around the Iα promoter when each 80 bp Iα switch repeat contains the two CpG sites. Thus, a relatively low density of CpG sites within the switch repeats can induce upstream CpG methylation at the IgH alpha locus, and cause a substantial decrease in transcription from the sterile transcript promoter. This effect is likely the reason that switch regions evolved to contain very few CpG sites. We discuss these findings as they relate to DNA methylation and to Ig CSR. Copyright © 2015 Elsevier Ltd. All rights reserved.

Is there a general task switching ability?

PubMed

Yehene, Einat; Meiran, Nachshon

2007-11-01

Participants were tested on two analogous task switching paradigms involving Shape/Size tasks and Vertical/Horizontal tasks, respectively, and three measures of psychometric intelligence, tapping fluid, crystallized and perceptual speed abilities. The paradigms produced similar patterns of group mean reaction times (RTs) and the vast majority of the participants showed switching cost (switch RT minus repeat RT), mixing cost (repeat RT minus single-task RT) and congruency effects. The shared intra-individual variance across paradigms and with psychometric intelligence served as criteria for general ability. Structural equations modeling indicated that switching cost with ample preparation ("residual cost") and mixing cost met these criteria. However, switching cost with little preparation and congruency effects were predominantly paradigm specific.

Visual contribution to the multistable perception of speech.

PubMed

Sato, Marc; Basirat, Anahita; Schwartz, Jean-Luc

2007-11-01

The multistable perception of speech, or verbal transformation effect, refers to perceptual changes experienced while listening to a speech form that is repeated rapidly and continuously. In order to test whether visual information from the speaker's articulatory gestures may modify the emergence and stability of verbal auditory percepts, subjects were instructed to report any perceptual changes during unimodal, audiovisual, and incongruent audiovisual presentations of distinct repeated syllables. In a first experiment, the perceptual stability of reported auditory percepts was significantly modulated by the modality of presentation. In a second experiment, when audiovisual stimuli consisting of a stable audio track dubbed with a video track that alternated between congruent and incongruent stimuli were presented, a strong correlation between the timing of perceptual transitions and the timing of video switches was found. Finally, a third experiment showed that the vocal tract opening onset event provided by the visual input could play the role of a bootstrap mechanism in the search for transformations. Altogether, these results demonstrate the capacity of visual information to control the multistable perception of speech in its phonetic content and temporal course. The verbal transformation effect thus provides a useful experimental paradigm to explore audiovisual interactions in speech perception.

Differential Effects of Aging on Processes Underlying Task Switching

ERIC Educational Resources Information Center

West, Robert; Travers, Stephanie

2008-01-01

In this study, we used event-related brain potentials (ERPs) to examine the effects of aging on processes underlying task switching. The response time data revealed an age-related increase in mixing costs before controlling for general slowing and no effect of aging on switching costs. In the cue-locked epoch, the ERP data revealed little effect…

Visual and cross-modal cues increase the identification of overlapping visual stimuli in Balint's syndrome.

PubMed

D'Imperio, Daniela; Scandola, Michele; Gobbetto, Valeria; Bulgarelli, Cristina; Salgarello, Matteo; Avesani, Renato; Moro, Valentina

2017-10-01

Cross-modal interactions improve the processing of external stimuli, particularly when an isolated sensory modality is impaired. When information from different modalities is integrated, object recognition is facilitated probably as a result of bottom-up and top-down processes. The aim of this study was to investigate the potential effects of cross-modal stimulation in a case of simultanagnosia. We report a detailed analysis of clinical symptoms and an 18 F-fluorodeoxyglucose (FDG) brain positron emission tomography/computed tomography (PET/CT) study of a patient affected by Balint's syndrome, a rare and invasive visual-spatial disorder following bilateral parieto-occipital lesions. An experiment was conducted to investigate the effects of visual and nonvisual cues on performance in tasks involving the recognition of overlapping pictures. Four modalities of sensory cues were used: visual, tactile, olfactory, and auditory. Data from neuropsychological tests showed the presence of ocular apraxia, optic ataxia, and simultanagnosia. The results of the experiment indicate a positive effect of the cues on the recognition of overlapping pictures, not only in the identification of the congruent valid-cued stimulus (target) but also in the identification of the other, noncued stimuli. All the sensory modalities analyzed (except the auditory stimulus) were efficacious in terms of increasing visual recognition. Cross-modal integration improved the patient's ability to recognize overlapping figures. However, while in the visual unimodal modality both bottom-up (priming, familiarity effect, disengagement of attention) and top-down processes (mental representation and short-term memory, the endogenous orientation of attention) are involved, in the cross-modal integration it is semantic representations that mainly activate visual recognition processes. These results are potentially useful for the design of rehabilitation training for attentional and visual-perceptual deficits.

A Low-G Silicon Inertial Micro-Switch with Enhanced Contact Effect Using Squeeze-Film Damping.

PubMed

Peng, Yingchun; Wen, Zhiyu; Li, Dongling; Shang, Zhengguo

2017-02-16

Contact time is one of the most important properties for inertial micro-switches. However, it is usually less than 20 μs for the switch with rigid electrode, which is difficult for the external circuit to recognize. This issue is traditionally addressed by designing the switch with a keep-close function or flexible electrode. However, the switch with keep-close function requires an additional operation to re-open itself, causing inconvenience for some applications wherein repeated monitoring is needed. The switch with a flexible electrode is usually fabricated by electroplating technology, and it is difficult to realize low-g switches (<50 g) due to inherent fabrication errors. This paper reports a contact enhancement using squeeze-film damping effect for low-g switches. A vertically driven switch with large proof mass and flexible springs was designed based on silicon micromachining, in order to achieve a damping ratio of 2 and a threshold value of 10 g. The proposed contact enhancement was investigated by theoretical and experimental studies. The results show that the damping effect can not only prolong the contact time for the dynamic acceleration load, but also reduce the contact bounce for the quasi-static acceleration load. The contact time under dynamic and quasi-static loads was 40 μs and 570 μs, respectively.

The Minimum Requirements of Language Control: Evidence from Sequential Predictability Effects in Language Switching

ERIC Educational Resources Information Center

Declerck, Mathieu; Koch, Iring; Philipp, Andrea M.

2015-01-01

The current study systematically examined the influence of sequential predictability of languages and concepts on language switching. To this end, 2 language switching paradigms were combined. To measure language switching with a random sequence of languages and/or concepts, we used a language switching paradigm that implements visual cues and…

Does the modality effect exist? And if so, which modality effect?

PubMed

Reinwein, Joachim

2012-02-01

The modality effect is a central issue in multimedia learning [see Mayer (Cambridge University Press, 2005a), for a review]. Sweller's Cognitive Load Theory (CLT), for example, presumes that an illustrated text is better understood when presented visually rather than orally. The predictive power of CLT lies in how it links in to Baddeley's (1986) model of working memory and Penney's (Mem Cognit 17:398-442, 1989) Separate-Streams Hypothesis. Ginns's (Learn Instr 4:313-331, 2005) recent meta-analysis also supports the modality effect (d = 0.72, based on 43 independent effects). This article replicates the meta-analysis of the modality effect based on 86 independent effects (with within-study subgroups as the unit of analysis and with mean of the outcomes as the dependent measure), with results showing a reduction of the overall effect size by almost half (d = 0.38), and even more when Duval and Tweedie's Trim and Fill method is used to correct publication bias (d = 0.20). This article also widens the scope of the analysis of moderator variables (e.g. Pace of presentation, Type of visualization, Research group) as well as their potentially confounded effects. Finally, it is argued that, for theoretical reasons, the so-called modality effect cannot be based on Penney's or Baddeley's theories and must be explained in a different way.

Can task-switching training enhance executive control functioning in children with attention deficit/-hyperactivity disorder?

PubMed

Kray, Jutta; Karbach, Julia; Haenig, Susann; Freitag, Christine

2011-01-01

The key cognitive impairments of children with attention deficit/-hyperactivity disorder (ADHD) include executive control functions such as inhibitory control, task-switching, and working memory (WM). In this training study we examined whether task-switching training leads to improvements in these functions. Twenty children with combined type ADHD and stable methylphenidate medication performed a single-task and a task-switching training in a crossover training design. The children were randomly assigned to one of two groups. One group started with the single-task training and then performed the task-switching training and the other group vice versa. The effectiveness of the task-switching training was measured as performance improvements (relative to the single-task training) on a structurally similar but new switching task and on other executive control tasks measuring inhibitory control and verbal WM as well as on fluid intelligence (reasoning). The children in both groups showed improvements in task-switching, that is, a reduction of switching costs, but not in performing the single-tasks across four training sessions. Moreover, the task-switching training lead to selective enhancements in task-switching performance, that is, the reduction of task-switching costs was found to be larger after task-switching than after single-task training. Similar selective improvements were observed for inhibitory control and verbal WM, but not for reasoning. Results of this study suggest that task-switching training is an effective cognitive intervention that helps to enhance executive control functioning in children with ADHD.

Can Task-Switching Training Enhance Executive Control Functioning in Children with Attention Deficit/-Hyperactivity Disorder?

PubMed Central

Kray, Jutta; Karbach, Julia; Haenig, Susann; Freitag, Christine

2012-01-01

The key cognitive impairments of children with attention deficit/-hyperactivity disorder (ADHD) include executive control functions such as inhibitory control, task-switching, and working memory (WM). In this training study we examined whether task-switching training leads to improvements in these functions. Twenty children with combined type ADHD and stable methylphenidate medication performed a single-task and a task-switching training in a crossover training design. The children were randomly assigned to one of two groups. One group started with the single-task training and then performed the task-switching training and the other group vice versa. The effectiveness of the task-switching training was measured as performance improvements (relative to the single-task training) on a structurally similar but new switching task and on other executive control tasks measuring inhibitory control and verbal WM as well as on fluid intelligence (reasoning). The children in both groups showed improvements in task-switching, that is, a reduction of switching costs, but not in performing the single-tasks across four training sessions. Moreover, the task-switching training lead to selective enhancements in task-switching performance, that is, the reduction of task-switching costs was found to be larger after task-switching than after single-task training. Similar selective improvements were observed for inhibitory control and verbal WM, but not for reasoning. Results of this study suggest that task-switching training is an effective cognitive intervention that helps to enhance executive control functioning in children with ADHD. PMID:22291628

Quantum Zeno Blockade for Next Generation Optical Switching in Fiber Systems

DTIC Science & Technology

2013-09-01

and utilized a self - referential quantum process tomography method to observe the Zeno effect in optical fiber using the ultrafast all- optical switch...controllable and can be used as a knob to study the core physics behind the Zeno-based switching. For this experiment, we developed a self - referential ...efficient optical communications. The quantum Zeno effect can be used to induce or inhibit optical switching through a variety of processes , all of

Spin-orbit torque-induced switching in ferrimagnetic alloys: Experiments and modeling

NASA Astrophysics Data System (ADS)

Je, Soong-Geun; Rojas-Sánchez, Juan-Carlos; Pham, Thai Ha; Vallobra, Pierre; Malinowski, Gregory; Lacour, Daniel; Fache, Thibaud; Cyrille, Marie-Claire; Kim, Dae-Yun; Choe, Sug-Bong; Belmeguenai, Mohamed; Hehn, Michel; Mangin, Stéphane; Gaudin, Gilles; Boulle, Olivier

2018-02-01

We investigate spin-orbit torque (SOT)-induced switching in rare-earth-transition metal ferrimagnetic alloys using W/CoTb bilayers. The switching current is found to vary continuously with the alloy concentration, and no reduction in the switching current is observed at the magnetic compensation point despite a very large SOT efficiency. A model based on coupled Landau-Lifschitz-Gilbert (LLG) equations shows that the switching current density scales with the effective perpendicular anisotropy which does not exhibit strong reduction at the magnetic compensation, explaining the behavior of the switching current density. This model also suggests that conventional SOT effective field measurements do not allow one to conclude whether the spins are transferred to one sublattice or just simply to the net magnetization. The effective spin Hall angle measurement shows an enhancement of the spin Hall angle with the Tb concentration which suggests an additional SOT contribution from the rare earth Tb atoms.

Task Switching Effects in Anticipation Timing

ERIC Educational Resources Information Center

Fairbrother, Jeffrey T.; Brueckner, Sebastian

2008-01-01

To understand how task switching affects human performance, there is a need to investigate how it influences the performance of tasks other than those involving bivalent stimulus categorization. The purpose of this study, therefore, was to investigate the effects of task switching on anticipation timing performance, which typically requires…

Compensation of voltage drops in solid-state switches used with thermoelectric generators

NASA Technical Reports Server (NTRS)

Shimada, K.

1972-01-01

Seebeck effect solid state switch was developed eliminating thermoelectric generator switch voltage drops. Semiconductor switches were fabricated from materials with large Seebeck coefficients, arranged such that Seebeck potential is generated with such polarity that current flow is aided.

Ultra High-Speed Radio Frequency Switch Based on Photonics.

PubMed

Ge, Jia; Fok, Mable P

2015-11-26

Microwave switches, or Radio Frequency (RF) switches have been intensively used in microwave systems for signal routing. Compared with the fast development of microwave and wireless systems, RF switches have been underdeveloped particularly in terms of switching speed and operating bandwidth. In this paper, we propose a photonics based RF switch that is capable of switching at tens of picoseconds speed, which is hundreds of times faster than any existing RF switch technologies. The high-speed switching property is achieved with the use of a rapidly tunable microwave photonic filter with tens of gigahertz frequency tuning speed, where the tuning mechanism is based on the ultra-fast electro-optics Pockels effect. The RF switch has a wide operation bandwidth of 12 GHz and can go up to 40 GHz, depending on the bandwidth of the modulator used in the scheme. The proposed RF switch can either work as an ON/OFF switch or a two-channel switch, tens of picoseconds switching speed is experimentally observed for both type of switches.

Restraining for switching effects in an AC driving pixel circuit of the OLED-on-silicon

NASA Astrophysics Data System (ADS)

Liu, Yan-Yan; Geng, Wei-Dong; Dai, Yong-Ping

2010-03-01

The AC driving scheme for OLEDs, which uses the pixel circuit with two transistors and one capacitor (2T1C), can extend the lifetime of the active matrix organic light-emitting diode (AMOLED) on silicon, but there are switching effects during the switch of AC signals, which result in the voltage variation on the storage capacitor and cause the current glitch in OLED. That would decrease the gray scale of the OLED. This paper proposes a novel pixel circuit consisting of three transistors and one capacitor to realize AC driving for the OLED-on-silicon while restraining the switching effects. Simulation results indicate that the proposed circuit is less sensitive to switching effects. Also, another pixel circuit is proposed to further reduce the driving current to meet the current constraints for the OLED-on-silicon.

Design of cladding rods-assisted depressed-core few-mode fibers with improved modal spacing

NASA Astrophysics Data System (ADS)

Han, Jiawei; Zhang, Jie

2018-03-01

This paper investigates the design details of cladding rods-assisted (CRA) depressed-core (DC) few-mode fibers (FMFs) that feature more equally spaced linearly polarized (LP) modal effective indices, suitable for high-spatial-density weakly-coupled mode-division multiplexing systems. The influences of the index profile of cladding rods on LP mode-resolved effective index, bending sensitivity, and effective area Aeff, are numerically described. Based on the design considerations of LP modal Aeff-dependent spatial efficiency and LP modal bending loss-dependent robustness, the small LP21-LP02 and LP22-LP03 modal spacing limitations, encountered in state-of-the-art weakly-coupled step-index FMFs, have been substantially improved by at least 25%. In addition, the proposed CRA DC FMFs also show sufficiently large effective areas (in excess of 110 μm2) for all guided LP modes, which are expected to exhibit good nonlinear performance.

Relationship between individual differences in speech processing and cognitive functions.

PubMed

Ou, Jinghua; Law, Sam-Po; Fung, Roxana

2015-12-01

A growing body of research has suggested that cognitive abilities may play a role in individual differences in speech processing. The present study took advantage of a widespread linguistic phenomenon of sound change to systematically assess the relationships between speech processing and various components of attention and working memory in the auditory and visual modalities among typically developed Cantonese-speaking individuals. The individual variations in speech processing are captured in an ongoing sound change-tone merging in Hong Kong Cantonese, in which typically developed native speakers are reported to lose the distinctions between some tonal contrasts in perception and/or production. Three groups of participants were recruited, with a first group of good perception and production, a second group of good perception but poor production, and a third group of good production but poor perception. Our findings revealed that modality-independent abilities of attentional switching/control and working memory might contribute to individual differences in patterns of speech perception and production as well as discrimination latencies among typically developed speakers. The findings not only have the potential to generalize to speech processing in other languages, but also broaden our understanding of the omnipresent phenomenon of language change in all languages.

All-optical universal logic gates on nonlinear multimode interference coupler using tunable input intensity

NASA Astrophysics Data System (ADS)

Tajaldini, Mehdi; Jafri, Mohd Zubir Mat

2015-04-01

The theory of Nonlinear Modal Propagation Analysis Method (NMPA) have shown significant features of nonlinear multimode interference (MMI) coupler with compact dimension and when launched near the threshold of nonlinearity. Moreover, NMPA have the potential to allow studying the nonlinear MMI based the modal interference to explorer the phenomenon that what happen due to the natural of multimode region. Proposal of all-optical switch based NMPA has approved its capability to achieving the all-optical gates. All-optical gates have attracted increasing attention due to their practical utility in all-optical signal processing networks and systems. Nonlinear multimode interference devices could apply as universal all-optical gates due to significant features that NMPA introduce them. In this Paper, we present a novel Ultra-compact MMI coupler based on NMPA method in low intensity compared to last reports either as a novel design method and potential application for optical NAND, NOR as universal gates on single structure for Boolean logic signal processing devices and optimize their application via studding the contrast ratio between ON and OFF as a function of output width. We have applied NMPA for several applications so that the miniaturization in low nonlinear intensities is their main purpose.

The modality effect of ego depletion: Auditory task modality reduces ego depletion.

PubMed

Li, Qiong; Wang, Zhenhong

2016-08-01

An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

A study of exercise modality and physical self-esteem in breast cancer survivors.

PubMed

Musanti, Rita

2012-02-01

This study, theoretically based on the Exercise Self-Esteem Model, EXSEM, examined effects of exercise modality on physical and global self-esteem (PSE, GSE) in breast cancer survivors. The EXSEM posits GSE at the apex with PSE feeding into GSE. PSE has three subdomains: physical condition (PC), attractive body (AB), and physical strength (PS). The goals were to compare the effect of combination modality versus single-modality exercise on PSE and GSE and to explore the relationship between exercise modality and the subdomains of PSE. Survivors were randomly allocated to flexibility (F), aerobic (A), resistance (R), or aerobic plus resistance (AR), 12-wk, individualized, home-based exercise program. Pre/posttesting included submaximal treadmill test, six-repetition maximum chest press and leg press, YMCA bench press, shoulder/hip flexibility, and bioelectric impedance analysis body composition. Esteem measures were the Physical Self-Perception Profile and the Rosenberg Self-Esteem Scale. Forty-two women completed the study (F = 12, A = 10, R = 9, and AR = 11). Fitness improvements congruent with exercise modality were seen in all groups. PSE and GSE outcomes did not reveal a greater effect from the combination modality program, AR, compared with the single-modality programs A and R. The relationships between the single-modality groups and the subdomains of PC, PS, and AB were supported in the R group (PS and AB increased) and were partially supported in the A group (PC, not AB, increased). A single-modality R program significantly improved all domains of PSE, and participation in the A program improved the PC subdomain. The combination exercise program did not enhance PSE greater than the single-modality programs. EXSEM was a useful framework for exploring esteem in breast cancer survivors.

The physiologic basis and clinical applications of cryotherapy and thermotherapy for the pain practitioner.

PubMed

Nadler, Scott F; Weingand, Kurt; Kruse, Roger J

2004-07-01

Cryotherapy and thermotherapy are useful adjuncts for the treatment of musculoskeletal injuries. Clinicians treating these conditions should be aware of current research findings regarding these modalities, because their choice of modality may affect the ultimate outcome of the patient being treated. Through a better understanding of these modalities, clinicians can optimize their present treatment strategies. Although cold and hot treatment modalities both decrease pain and muscle spasm, they have opposite effects on tissue metabolism, blood flow, inflammation, edema, and connective tissue extensibility. Cryotherapy decreases these effects while thermotherapy increases them. Continuous low-level cryotherapy and thermotherapy are newer concepts in therapeutic modalities. Both modalities provide significant pain relief with a low side-effect profile. Contrast therapy, which alternates between hot and cold treatment modalities, provides no additional therapeutic benefits compared with cryotherapy or thermotherapy alone. Complications of cryotherapy include nerve damage, frostbite, Raynaud's phenomenon, cold-induced urticaria, and slowed wound healing. With thermotherapy, skin burns may occur, especially in patients with diabetes mellitus, multiple sclerosis, poor circulation, and spinal cord injuries. In individuals with rheumatoid arthritis, deep-heating modalities should be used with caution because increased inflammation may occur. Whirlpool and other types of hydrotherapy have caused infections of the skin, urogenital, and pulmonary systems. Additionally, ultrasound should not be used in patients with joint prostheses.

Studying the Polarization Switching in Polycrystalline BiFeO3 Films by 2D Piezoresponse Force Microscopy

NASA Astrophysics Data System (ADS)

Jin, Yaming; Lu, Xiaomei; Zhang, Junting; Kan, Yi; Bo, Huifeng; Huang, Fengzhen; Xu, Tingting; Du, Yingchao; Xiao, Shuyu; Zhu, Jinsong

2015-07-01

For rhombohedral multiferroelectrics, non-180° ferroelectric domain switching may induce ferroelastic and/or (anti-)ferromagnetic effect. So the determination and control of ferroelectric domain switching angles is crucial for nonvolatile information storage and exchange-coupled magnetoelectric devices. We try to study the intrinsic characters of polarization switching in BiFeO3 by introducing a special data processing method to determine the switching angle from 2D PFM (Piezoresponse Force Microscopy) images of randomly oriented samples. The response surface of BiFeO3 is first plotted using the piezoelectric tensor got from first principles calculations. Then from the normalized 2D PFM signals before and after switching, the switching angles of randomly oriented BiFeO3 grains can be determined through numerical calculations. In the polycrystalline BiFeO3 films, up to 34% of all switched area is that with original out-of-plane (OP) polarization parallel to the poling field. 71° polarization switching is more favorable, with the area percentages of 71°, 109° and 180° domain switching being about 42%, 29% and 29%, respectively. Our analysis further reveals that IP stress and charge migration have comparable effect on switching, and they are sensitive to the geometric arrangements. This work helps exploring a route to control polarization switching in BiFeO3, so as to realize desirable magnetoelectric coupling.

Effectiveness and Cost-effectiveness of Four Treatment Modalities for Substance Disorders: A Propensity Score Analysis

PubMed Central

Mojtabai, Ramin; Graff Zivin, Joshua

2003-01-01

Objective To assess the effectiveness and cost-effectiveness of four treatment modalities for substance abuse. Data Sources The study used data from the Services Research Outcomes Study (SROS), a survey of 3,047 clients in a random sample of 99 drug treatment facilities across the United States. Detailed sociodemographic, substance use, and clinical data were abstracted from treatment records. Substance abuse outcome and treatment history following discharge from index facilities were assessed using a comprehensive interview with 1,799 of these individuals five years after discharge. Treatment success was defined in two ways: as abstinence and as any reduction in substance use. Study Design Effectiveness and cost-effectiveness of four modalities were compared: inpatient, residential, outpatient detox/methadone, and outpatient drug-free. Clients were stratified based on propensity scores and analyses were conducted within these strata. Sensitivity analyses examined the impact of future substance abuse treatment on effectiveness and cost-effectiveness estimates. Principal Findings Treatment of substance disorders appears to be cost-effective compared to other health interventions. The cost per successfully treated abstinent case in the least costly modality, the outpatient drug-free programs, was $6,300 (95 percent confidence intervals: $5,200–$7,900) in 1990 dollars. There were only minor differences between various modalities of treatment with regard to effectiveness. However, modalities varied considerably with regard to cost-effectiveness. Outpatient drug-free programs were the most cost-effective. There was little evidence that relative effectiveness or cost-effectiveness of programs varied according to factors that were associated with selection into different programs. Conclusions Substance disorders can be treated most cost-effectively in outpatient drug-free settings. Savings from transitioning to the most cost-effective treatment modality may free resources that could be reinvested to improve access to substance abuse treatment for a larger number of individuals in need of such treatment. PMID:12650390

Non-destructive reversible resistive switching in Cr doped Mott insulator Ca2RuO4: Interface vs bulk effects

NASA Astrophysics Data System (ADS)

Shen, Shida; Williamson, Morgan; Cao, Gang; Zhou, Jianshi; Goodenough, John; Tsoi, Maxim

2017-12-01

A non-destructive reversible resistive switching is demonstrated in single crystals of Cr-doped Mott insulator Ca2RuO4. An applied electrical bias was shown to reduce the DC resistance of the crystal by as much as 75%. The original resistance of the sample could be restored by applying an electrical bias of opposite polarity. We have studied this resistive switching as a function of the bias strength, applied magnetic field, and temperature. A combination of 2-, 3-, and 4-probe measurements provide a means to distinguish between bulk and interfacial contributions to the switching and suggests that the switching is mostly an interfacial effect. The switching was tentatively attributed to electric-field driven lattice distortions which accompany the impurity-induced Mott transition. This field effect was confirmed by temperature-dependent resistivity measurements which show that the activation energy of this material can be tuned by an applied DC electrical bias. The observed resistance switching can potentially be used for building non-volatile memory devices like resistive random access memory.

Multistate storage nonvolatile memory device based on ferroelectricity and resistive switching effects of SrBi2Ta2O9 films

NASA Astrophysics Data System (ADS)

Song, Zhiwei; Li, Gang; Xiong, Ying; Cheng, Chuanpin; Zhang, Wanli; Tang, Minghua; Li, Zheng; He, Jiangheng

2018-05-01

A memory device with a Pt/SrBi2Ta2O9(SBT)/Pt(111) structure was shown to have excellent combined ferroelectricity and resistive switching properties, leading to higher multistate storage memory capacity in contrast to ferroelectric memory devices. In this device, SBT polycrystalline thin films with significant (115) orientation were fabricated on Pt(111)/Ti/SiO2/Si(100) substrates using CVD (chemical vapor deposition) method. Measurement results of the electric properties exhibit reproducible and reliable ferroelectricity switching behavior and bipolar resistive switching effects (BRS) without an electroforming process. The ON/OFF ratio of the resistive switching was found to be about 103. Switching mechanisms for the low resistance state (LRS) and high resistance state (HRS) currents are likely attributed to the Ohmic and space charge-limited current (SCLC) behavior, respectively. Moreover, the ferroelectricity and resistive switching effects were found to be mutually independent, and the four logic states were obtained by controlling the periodic sweeping voltage. This work holds great promise for nonvolatile multistate memory devices with high capacity and low cost.

The effectiveness of psychosocial modalities in the treatment of alcohol problems in adults: a review of the evidence.

PubMed

Martin, Garth W; Rehm, Jürgen

2012-06-01

Our objectives were to review the effectiveness of psychosocial modalities in the treatment of alcohol use disorders and problems, and to examine the impact of therapists on treatment outcome, the evidence on best practices for comorbid conditions, and the evidence on treatment matching. We based our review on published systematic reviews of this topic after 2000. There is strong evidence that some, but not all, psychosocial treatments are effective in treating alcohol problems. Those with the strongest empirical support are motivational enhancement therapy, various cognitive-behavioural interventions, and brief interventions. Meta-analyses for several of these modalities suggest typical effect sizes in the low-to-moderate range. When these modalities have been compared with one another in well-designed clinical trials, they have been shown to be of comparable effectiveness. There is little basis on which to recommend one of these modalities over another but good reason to select from among them.

The Influence of Feedback on Task-Switching Performance: A Drift Diffusion Modeling Account.

PubMed

Cohen Hoffing, Russell; Karvelis, Povilas; Rupprechter, Samuel; Seriès, Peggy; Seitz, Aaron R

2018-01-01

Task-switching is an important cognitive skill that facilitates our ability to choose appropriate behavior in a varied and changing environment. Task-switching training studies have sought to improve this ability by practicing switching between multiple tasks. However, an efficacious training paradigm has been difficult to develop in part due to findings that small differences in task parameters influence switching behavior in a non-trivial manner. Here, for the first time we employ the Drift Diffusion Model (DDM) to understand the influence of feedback on task-switching and investigate how drift diffusion parameters change over the course of task switch training. We trained 316 participants on a simple task where they alternated sorting stimuli by color or by shape. Feedback differed in six different ways between subjects groups, ranging from No Feedback (NFB) to a variety of manipulations addressing trial-wise vs. Block Feedback (BFB), rewards vs. punishments, payment bonuses and different payouts depending upon the trial type (switch/non-switch). While overall performance was found to be affected by feedback, no effect of feedback was found on task-switching learning. Drift Diffusion Modeling revealed that the reductions in reaction time (RT) switch cost over the course of training were driven by a continually decreasing decision boundary. Furthermore, feedback effects on RT switch cost were also driven by differences in decision boundary, but not in drift rate. These results reveal that participants systematically modified their task-switching performance without yielding an overall gain in performance.

Task switching in a hierarchical task structure: evidence for the fragility of the task repetition benefit.

PubMed

Lien, Mei-Ching; Ruthruff, Eric

2004-05-01

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms. In Experiments 2-5, adjacent task elements were grouped temporally and/or spatially (forming an ensemble) to create a hierarchical task organization. Results indicate that the effect of switching at the ensemble level dominated the effect of switching at the element level. Experiments 6 and 7, using an ensemble of 3 task elements, revealed that the element-level switch cost was virtually absent between ensembles but was large within an ensemble. The authors conclude that the element-level task repetition benefit is fragile and can be eliminated in a hierarchical task organization.

Task switching in a hierarchical task structure: evidence for the fragility of the task repetition benefit

NASA Technical Reports Server (NTRS)

Lien, Mei-Ching; Ruthruff, Eric

2004-01-01

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms. In Experiments 2-5, adjacent task elements were grouped temporally and/or spatially (forming an ensemble) to create a hierarchical task organization. Results indicate that the effect of switching at the ensemble level dominated the effect of switching at the element level. Experiments 6 and 7, using an ensemble of 3 task elements, revealed that the element-level switch cost was virtually absent between ensembles but was large within an ensemble. The authors conclude that the element-level task repetition benefit is fragile and can be eliminated in a hierarchical task organization.

76 FR 72026 - Buy America Waiver Notification

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-21

... regarding the FHWA's finding that a Buy America waiver is appropriate for an automated battery switching mechanism for an electric battery switching station in the State of California. DATES: The effective date of... automated battery switching mechanism for an electric battery switching station in California. In accordance...

[Effect of sound amplification on parent's communicative modalities].

PubMed

Couto, Maria Inês Vieira; Lichtig, Ida

2007-01-01

auditory rehabilitation in deaf children users of sign language. to verify the effects of sound amplification on parent's communicative modalities when interacting with their deaf children. participants were twelve deaf children, aged 50 to 80 months and their hearing parents. Children had severe or profound hearing loss in their better ear and were fitted with hearing aids in both ears. Children communicated preferably through sign language. The cause-effect relation between the children's auditory skills profile (insertion gain, functional gain and The Meaningful Auditory Integration Scale--MAIS) and the communicative modalities (auditive-oral, visuo-spacial, bimodal) used by parents was analyzed. Communicative modalities were compared in two different experimental situations during a structured interaction between parents and children, i.e. when children were not fitted with their hearing aids (Situation 1) and when children were fitted with them (Situation 2). Data was analyzed using descriptive statistics. the profile of the deaf children's auditory skills demonstrated to be lower than 53% (unsatisfactory). Parents used predominately the bimodal modality to gain children's attention, to transmit and to end tasks. A slight positive effect of sound amplification on the communicative modalities was observed, once parents presented more turn-takings during communication when using the auditory-oral modality in Situation 2. hearing parents tend to use more turn-takings during communication in the auditory-oral modality to gain children's attention, to transmit and to end tasks, since they observe an improvement in the auditory skills of their children.

Cost-effectiveness analysis of valsartan versus losartan and the effect of switching.

PubMed

Baker, Timothy M; Goh, Jowern; Johnston, Atholl; Falvey, Heather; Brede, Yvonne; Brown, Ruth E

2012-01-01

Losartan will shortly become generic, and this may encourage switching to the generic drug. However, valsartan was shown in a meta-analysis to be statistically superior in lowering blood pressure (BP) to losartan. This paper examines the costs of treatment with these two drugs and the potential consequences of switching established valsartan patients to generic losartan. A US payer cost-effectiveness model was developed incorporating the risk of cardiovascular disease (CVD) events related to systolic blood pressure (SBP) control comparing valsartan to continual losartan and switching from valsartan to generic losartan. The model, based upon a meta-analysis by Nixon et al. and Framingham equations, included first CVD event costs calculated from US administrative data sets and utility values from published sources. The modeled outcomes were number of CVD events, costs and incremental cost per quality-adjusted life-year (QALY) and life-year (LY). Fewer patients had fatal and non-fatal CVD events with valsartan therapy compared with continual losartan and with patients switched from valsartan to generic losartan. The base-case model results indicated that continued treatment with valsartan had an incremental cost-effectiveness ratio of $27,268 and $25,460 per life year gained, and $32,313 and $30,170 per QALY gained, relative to continual losartan and switching treatments, respectively. Sensitivity analyses found that patient discontinuation post-switching was a sensitive parameter. Including efficacy offsets with lowered adherence or discontinuation resulted in more favorable ratios for valsartan compared to switching therapy. The model does not evaluate post-primary CVD events and considers change in SBP from baseline level as the sole predictor of CVD risk. Valsartan appears to be cost-effective compared to switching to generic losartan and switching to the generic drug does not support a cost offset argument over the longer term. Physicians should continue to consider the needs of individual patient and not cost offsets.

Picosecond High Pressure Gas Switch Experiment

DTIC Science & Technology

1993-06-01

the calculated pulse waveform for a much higher voltage and pressure switch . Also, a discussion of the modifications made on an existing pulse...s 80 8 ~ 60 J 40 .. : ~--~: __ ~’----~-~ 0.1 10 100 1000 Frequency Figure 7. Output switch recovery. Conclusion The high- pressure switch has...effective in matching experimental results, and should thus be useful in the design of high-voltage and pressure switch configurations

Stimulus-Category and Response-Repetition Effects in Task Switching: An Evaluation of Four Explanations

ERIC Educational Resources Information Center

Druey, Michel D.

2014-01-01

In many task-switch studies, task sequence and response sequence interact: Response repetitions produce benefits when the task repeats but produce costs when the task switches. Four different theoretical frameworks have been proposed to explain these effects: a reconfiguration-based account, association-learning models, an episodic-retrieval…

Enhancing resource coordination for multi-modal evacuation planning.

DOT National Transportation Integrated Search

2013-01-01

This research project seeks to increase knowledge about coordinating effective multi-modal evacuation for disasters. It does so by identifying, evaluating, and assessing : current transportation management approaches for multi-modal evacuation planni...

RF-MEMS capacitive switches with high reliability

DOEpatents

Goldsmith, Charles L.; Auciello, Orlando H.; Carlisle, John A.; Sampath, Suresh; Sumant, Anirudha V.; Carpick, Robert W.; Hwang, James; Mancini, Derrick C.; Gudeman, Chris

2013-09-03

A reliable long life RF-MEMS capacitive switch is provided with a dielectric layer comprising a "fast discharge diamond dielectric layer" and enabling rapid switch recovery, dielectric layer charging and discharging that is efficient and effective to enable RF-MEMS switch operation to greater than or equal to 100 billion cycles.

Switching between Tasks and Responses: A Developmental Study

ERIC Educational Resources Information Center

Crone, Eveline A.; Bunge, Silvia A.; van der Molen, Maurits W.; Ridderinkhof, K. Richard

2006-01-01

Task switching requires the ability to flexibly switch between task rules and responses, and is sensitive to developmental change. We tested the hypothesis that developmental changes in task switch performance are associated with changes in the facilitating or interfering effect of the previously retrieved stimulus-response (S-R) association.…

Touching is believing: interrogating halide perovskite solar cells at the nanoscale via scanning probe microscopy

NASA Astrophysics Data System (ADS)

Li, Jiangyu; Huang, Boyuan; Nasr Esfahani, Ehsan; Wei, Linlin; Yao, Jianjun; Zhao, Jinjin; Chen, Wei

2017-10-01

Halide perovskite solar cells based on CH3NH3PbI3 and related materials have emerged as the most exciting development in the next generation photovoltaic technologies, yet the microscopic phenomena involving photo-carriers, ionic defects, spontaneous polarization, and molecular vibration and rotation interacting with numerous grains, grain boundaries, and interfaces are still inadequately understood. In fact, there is still need for an effective method to interrogate the local photovoltaic properties of halide perovskite solar cells that can be directly traced to their microstructures on one hand and linked to their device performance on the other hand. In this perspective, we propose that scanning probe microscopy (SPM) techniques have great potential to realize such promises at the nanoscale, and highlight some of the recent progresses and challenges along this line of investigation toward local probing of photocurrent, work function, ionic activities, polarization switching, and chemical degradation. We also emphasize the importance of multi-modality imaging, in-operando scanning, big data analysis, and multidisciplinary collaboration for further studies toward fully understanding of these complex systems.

Erythropoietin protects against rhabdomyolysis-induced acute kidney injury by modulating macrophage polarization

PubMed Central

Wang, Shuo; Zhang, Chao; Li, Jiawei; Niyazi, Sidikejiang; Zheng, Long; Xu, Ming; Rong, Ruiming; Yang, Cheng; Zhu, Tongyu

2017-01-01

Erythropoietin (EPO) is a well-known hormone that is clinically used for the treatment of anemia. Very recently, an increasing body of evidence showed that EPO could still regulate bioactivities of macrophages. However, the details about the immunomodulatory effect of EPO on macrophages are not fully delineated, particularly in the setting of renal damages. Therefore, in the present study, we determined whether EPO could exert an impact on the dynamics of macrophages in a well-established model of rhabdomyolysis-induced acute kidney injury and explored the potential mechanisms. EPO was found to ameliorate kidney injuries by reducing macrophages recruitment and promoting phenotype switch toward M2 macrophages in vivo. It was also confirmed that EPO could directly suppress pro-inflammatory responses of M1 macrophages and promote M2 marker expression in vitro. Data indicated the possible involvement of Jak2/STAT3/STAT6 pathway in the augmentation of EPO on M2 polarization. These results improved the understanding of the immunoregulatory capacity of EPO on macrophages, which might optimize the therapeutic modalities of EPO. PMID:28383559

Design and implementation of a novel modal space active force control concept for spatial multi-DOF parallel robotic manipulators actuated by electrical actuators.

PubMed

Yang, Chifu; Zhao, Jinsong; Li, Liyi; Agrawal, Sunil K

2018-01-01

Robotic spine brace based on parallel-actuated robotic system is a new device for treatment and sensing of scoliosis, however, the strong dynamic coupling and anisotropy problem of parallel manipulators result in accuracy loss of rehabilitation force control, including big error in direction and value of force. A novel active force control strategy named modal space force control is proposed to solve these problems. Considering the electrical driven system and contact environment, the mathematical model of spatial parallel manipulator is built. The strong dynamic coupling problem in force field is described via experiments as well as the anisotropy problem of work space of parallel manipulators. The effects of dynamic coupling on control design and performances are discussed, and the influences of anisotropy on accuracy are also addressed. With mass/inertia matrix and stiffness matrix of parallel manipulators, a modal matrix can be calculated by using eigenvalue decomposition. Making use of the orthogonality of modal matrix with mass matrix of parallel manipulators, the strong coupled dynamic equations expressed in work space or joint space of parallel manipulator may be transformed into decoupled equations formulated in modal space. According to this property, each force control channel is independent of others in the modal space, thus we proposed modal space force control concept which means the force controller is designed in modal space. A modal space active force control is designed and implemented with only a simple PID controller employed as exampled control method to show the differences, uniqueness, and benefits of modal space force control. Simulation and experimental results show that the proposed modal space force control concept can effectively overcome the effects of the strong dynamic coupling and anisotropy problem in the physical space, and modal space force control is thus a very useful control framework, which is better than the current joint space control and work space control. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Language control in bilingual language comprehension: evidence from the maze task

PubMed Central

Wang, Xin

2015-01-01

Most empirical evidence on switch costs is based on bilingual production and interpreted as a result of inhibitory control. It is unclear whether such a top–down control process exists in language switching during comprehension. This study investigates whether a non-lexical switch cost is involved in reading code-switched sentences and its relation to language dominance with cross-script bilingual readers. A maze task is adopted in order to separate top–down inhibitory effects, from lexical effects driven by input. The key findings are: (1) switch costs were observed in both L1–L2 and L2–L1 directions; (2) these effects were driven by two mechanisms: lexical activation and inhibitory control; (3) language dominance modulated the lexical effects, but did not affect the inhibitory effects. These results suggest that a language control mechanism is involved in bilingual reading, even though the control process is not driven by selection as in production. At the theoretical level, these results lend support for the Inhibitory Control model during language switching in comprehension; while the BIA/BIA+ model needs to incorporate a top–down control mechanism to be able to explain the current findings. PMID:26347675

Quasi-modal vibration control by means of active control bearings

NASA Technical Reports Server (NTRS)

Nonami, K.; Fleming, D. P.

1986-01-01

This paper investigates a design method of an active control bearing system with only velocity feedback. The study provides a new quasi-modal control method for a control system design of an active control bearing system in which feedback coefficients are determined on the basis of a modal analysis. Although the number of sensors and actuators is small, this quasi-modal control method produces a control effect close to an ideal modal control.

SU-E-T-410: Evaluation of Treatment Modalities for Stereotactic Lung Radiation Therapy: A Phantom Study

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

Mohatt, D; Malhotra, H

Purpose: To evaluate and verify the accuracy of alternative treatment modalities for stereotactic lung therapy with end-to-end testing. We compared three dimensional conformal therapy (3DCRT), dynamic conformal arc therapy (DCAT), intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) treatment using 6 MV, 6 MV flattening filter free (FFF) and 10 MV FFF photons. Methods: A QUASAR respiratory motion phantom was utilized with custom ion chamber and gafchromatic EBT2 film inserts. The phantom contained a low density lung medium with a cylindrical polystyrene tumor (35 cc). Pseudo representative structures for various organs at risk (OAR) were created. Allmore » treatment plans were created using Eclipse ver. 11 using the same image and structure sets, and delivered via Varian TrueBeam STx linear accelerator equipped with high definition MLC. Evaluation of plan quality followed ROTG 0813 criterion for conformity index (CI100%), high dose spillage, D2cm, and R50%. Results: All treatment plans met the OAR dose constraints per protocol and could be delivered without any beam hold offs or other interlocks and hence were deemed clinically safe. For equivalent beam energies, target conformity was improved for all modalities when switching to FFF mode. Treatment efficiency increased for VMAT FFF by a factor of 3–4 over IMRT, and up to factor of 7 when compared to 3DCRT. Pass rates were > 97% for all treatment using gamma criteria of 3%, 3mm. Absolute dose at iso-center was verified with ion chamber, and found to be within 2% of the treatment planning system. Conclusion: The higher dose rate associated with FFF not only reduces delivery times, but in most cases enhances plan quality. The one modality with succeeding best results for all RTOG criterions was VMAT 6 MV FFF. This end-to-end testing provides necessary confidence in the entire dose delivery chain for lung SBRT patients.« less

Identification of modal parameters including unmeasured forces and transient effects

NASA Astrophysics Data System (ADS)

Cauberghe, B.; Guillaume, P.; Verboven, P.; Parloo, E.

2003-08-01

In this paper, a frequency-domain method to estimate modal parameters from short data records with known input (measured) forces and unknown input forces is presented. The method can be used for an experimental modal analysis, an operational modal analysis (output-only data) and the combination of both. A traditional experimental and operational modal analysis in the frequency domain starts respectively, from frequency response functions and spectral density functions. To estimate these functions accurately sufficient data have to be available. The technique developed in this paper estimates the modal parameters directly from the Fourier spectra of the outputs and the known input. Instead of using Hanning windows on these short data records the transient effects are estimated simultaneously with the modal parameters. The method is illustrated, tested and validated by Monte Carlo simulations and experiments. The presented method to process short data sequences leads to unbiased estimates with a small variance in comparison to the more traditional approaches.

Analysis of structural response data using discrete modal filters. M.S. Thesis

NASA Technical Reports Server (NTRS)

Freudinger, Lawrence C.

1991-01-01

The application of reciprocal modal vectors to the analysis of structural response data is described. Reciprocal modal vectors are constructed using an existing experimental modal model and an existing frequency response matrix of a structure, and can be assembled into a matrix that effectively transforms the data from the physical space to a modal space within a particular frequency range. In other words, the weighting matrix necessary for modal vector orthogonality (typically the mass matrix) is contained within the reciprocal model matrix. The underlying goal of this work is mostly directed toward observing the modal state responses in the presence of unknown, possibly closed loop forcing functions, thus having an impact on both operating data analysis techniques and independent modal space control techniques. This study investigates the behavior of reciprocol modal vectors as modal filters with respect to certain calculation parameters and their performance with perturbed system frequency response data.

Systematic Genetic Screen for Transcriptional Regulators of the Candida albicans White-Opaque Switch

PubMed Central

Lohse, Matthew B.; Ene, Iuliana V.; Craik, Veronica B.; Hernday, Aaron D.; Mancera, Eugenio; Morschhäuser, Joachim; Bennett, Richard J.; Johnson, Alexander D.

2016-01-01

The human fungal pathogen Candida albicans can reversibly switch between two cell types named “white” and “opaque,” each of which is stable through many cell divisions. These two cell types differ in their ability to mate, their metabolic preferences and their interactions with the mammalian innate immune system. A highly interconnected network of eight transcriptional regulators has been shown to control switching between these two cell types. To identify additional regulators of the switch, we systematically and quantitatively measured white–opaque switching rates of 196 strains, each deleted for a specific transcriptional regulator. We identified 19 new regulators with at least a 10-fold effect on switching rates and an additional 14 new regulators with more subtle effects. To investigate how these regulators affect switching rates, we examined several criteria, including the binding of the eight known regulators of switching to the control region of each new regulatory gene, differential expression of the newly found genes between cell types, and the growth rate of each mutant strain. This study highlights the complexity of the transcriptional network that regulates the white–opaque switch and the extent to which switching is linked to a variety of metabolic processes, including respiration and carbon utilization. In addition to revealing specific insights, the information reported here provides a foundation to understand the highly complex coupling of white–opaque switching to cellular physiology. PMID:27280690

Some effects of overall rate of earning reinforcers on run lengths and visit durations.

PubMed

Macdonall, James S

2006-07-01

In a concurrent schedule, responding at each alternative is controlled by a pair of schedules that arrange reinforcers for staying at that alternative and reinforcers for switching to the other alternative. Each pair of schedules operates only while at the associated alternative. When only one pair of stay and switch schedules is presented, the rates of earning reinforcers for staying divided by the rates of earning reinforcers for switching controls the mean number responses in a visit and the mean duration of visits. The purpose of the present experiment was to see whether the sum of the rates of earning stay and switch reinforcers changed the way that run length and visit duration were affected by the ratio of the rates of stay to switch reinforcers. Rats were exposed to pairs of stay and switch schedules that varied both the ratio of the rates of earning stay and switch reinforcers and the sum of the rates of earning stay and switch reinforcers. Run lengths and visit durations were joint functions of the ratio of the rates of earning stay and switch reinforcers and the sum of the rates of earning stay and switch reinforcers. These results shows that the effect of the ratio of the sum of the rates of earning stay and switch reinforcers results from processes operating at the alternative, rather than from processes operating at both alternatives.

Spark gap switch with spiral gas flow

DOEpatents

Brucker, John P.

1989-01-01

A spark gap switch having a contaminate removal system using an injected gas. An annular plate concentric with an electrode of the switch defines flow paths for the injected gas which form a strong spiral flow of the gas in the housing which is effective to remove contaminates from the switch surfaces. The gas along with the contaminates is exhausted from the housing through one of the ends of the switch.

Effectiveness and usability of Scanning Wizard software: a tool for enhancing switch scanning.

PubMed

Koester, Heidi Horstmann; Simpson, Richard C

2017-11-24

Scanning Wizard software helps scanning users improve the setup of their switch and scanning system. This study evaluated Scanning Wizard's effectiveness and usability. Ten people who use switch scanning and ten practitioners used Scanning Wizard in the initial session. Usability was high, based on survey responses averaging over 4.5 out of 5, and qualitative feedback was very positive. Five switch users were able to complete the multi-week protocol, using settings on their own scanning system that were recommended from the Scanning Wizard session. Using these revised settings, text entry rates improved by an average of 71%, ranging from 29% to 172% improvement. Results suggest that Scanning Wizard is a useful tool for improving the configuration of scanning systems for people who use switch scanning to communicate. Implications for Rehabilitation Some individuals with severe physical impairments use switch scanning for spoken and written communication. Scanning Wizard software helps scanning users improve the setup of their switch and scanning system. This study demonstrated high usability of Scanning Wizard (with 10 switch userpractitioner teams) and increased text entry rate by an average of 71% (for five switch users). Results suggest that Scanning Wizard is a useful tool for improving the configuration of scanning systems for people who use switch scanning to communicate.

A three-sided rearrangeable switching network for a binary fat tree

NASA Astrophysics Data System (ADS)

Yen, Mao-Hsu; Yu, Chu; Shin, Haw-Yun; Chen, Sao-Jie

2011-06-01

A binary fat tree needs an internal node to interconnect the left-children, right-children and parent terminals to each other. In this article, we first propose a three-stage, 3-sided rearrangeable switching network for the implementation of a binary fat tree. The main component of this 3-sided switching network (3SSN) consists of a polygonal switch block (PSB) interconnected by crossbars. With the same size and the same number of switches as our 3SSN, a three-stage, 3-sided clique-based switching network is shown to be not rearrangeable. Also, the effects of the rearrangeable structure and the number of terminals on the network switch-efficiency are explored and a proper set of parameters has been determined to minimise the number of switches. We derive that a rearrangeable 3-sided switching network with switches proportional to N 3/2 is most suitable to interconnect N terminals. Moreover, we propose a new Polygonal Field Programmable Gate Array (PFPGA) that consists of logic blocks interconnected by our 3SSN, such that the logic blocks in this PFPGA can be grouped into clusters to implement different logic functions. Since the programmable switches usually have high resistance and capacitance and occupy a large area, we have to consider the effect of the 3SSN structure and the granularity of its cluster logic blocks on the switch efficiency of PFPGA. Experiments on benchmark circuits show that the switch and speed performances are significantly improved. Based on the experimental results, we can determine the parameters of PFPGA for the VLSI implementation.

Ultrafast magnetic vortex core switching driven by the topological inverse Faraday effect.

PubMed

Taguchi, Katsuhisa; Ohe, Jun-ichiro; Tatara, Gen

2012-09-21

We present a theoretical discovery of an unconventional mechanism of inverse Faraday effect which acts selectively on topological magnetic structures. The effect, topological inverse Faraday effect, is induced by the spin Berry's phase of the magnetic structure when a circularly polarized light is applied. Thus a spin-orbit interaction is not necessary unlike that in the conventional inverse Faraday effect. We demonstrate by numerical simulation that topological inverse Faraday effect realizes ultrafast switching of a magnetic vortex within a switching time of 150 ps without magnetic field.

Misremembering what you see or hear: Dissociable effects of modality on short- and long-term false recognition.

PubMed

Olszewska, Justyna M; Reuter-Lorenz, Patricia A; Munier, Emily; Bendler, Sara A

2015-09-01

False working memories readily emerge using a visual item-recognition variant of the converging associates task. Two experiments, manipulating study and test modality, extended prior working memory results by demonstrating a reliable false recognition effect (more false alarms to associatively related lures than to unrelated lures) within seconds of encoding in either the visual or auditory modality. However, false memories were nearly twice as frequent when study lists were seen than when they were heard, regardless of test modality, although study-test modality mismatch was generally disadvantageous (consistent with encoding specificity). A final experiment that varied study-test modality using a hybrid short- and long-term memory test (Flegal, Atkins & Reuter-Lorenz, 2010) replicated the auditory advantage in the short term but revealed a reversal in the long term: The false memory effect was greater in the auditory study-test condition than in the visual study-test condition. Thus, the same encoding conditions gave rise to an opposite modality advantage depending on whether recognition was tested under short-term or long-term memory conditions. Although demonstrating continuity in associative processing across delay, the results indicate that delay condition affects the availability of modality-dependent features of the memory trace and, thus, distinctiveness, leading to dissociable patterns of short- and long-term memory performance. (c) 2015 APA, all rights reserved).

Effect of physical workload and modality of information presentation on pattern recognition and navigation task performance by high-fit young males.

PubMed

Zahabi, Maryam; Zhang, Wenjuan; Pankok, Carl; Lau, Mei Ying; Shirley, James; Kaber, David

2017-11-01

Many occupations require both physical exertion and cognitive task performance. Knowledge of any interaction between physical demands and modalities of cognitive task information presentation can provide a basis for optimising performance. This study examined the effect of physical exertion and modality of information presentation on pattern recognition and navigation-related information processing. Results indicated males of equivalent high fitness, between the ages of 18 and 34, rely more on visual cues vs auditory or haptic for pattern recognition when exertion level is high. We found that navigation response time was shorter under low and medium exertion levels as compared to high intensity. Navigation accuracy was lower under high level exertion compared to medium and low levels. In general, findings indicated that use of the haptic modality for cognitive task cueing decreased accuracy in pattern recognition responses. Practitioner Summary: An examination was conducted on the effect of physical exertion and information presentation modality in pattern recognition and navigation. In occupations requiring information presentation to workers, who are simultaneously performing a physical task, the visual modality appears most effective under high level exertion while haptic cueing degrades performance.

Experimental strain modal analysis for beam-like structure by using distributed fiber optics and its damage detection

NASA Astrophysics Data System (ADS)

Cheng, Liangliang; Busca, Giorgio; Cigada, Alfredo

2017-07-01

Modal analysis is commonly considered as an effective tool to obtain the intrinsic characteristics of structures including natural frequencies, modal damping ratios, and mode shapes, which are significant indicators for monitoring the health status of engineering structures. The complex mode indicator function (CMIF) can be regarded as an effective numerical tool to perform modal analysis. In this paper, experimental strain modal analysis based on the CMIF has been introduced. Moreover, a distributed fiber-optic sensor, as a dense measuring device, has been applied to acquire strain data along a beam surface. Thanks to the dense spatial resolution of the distributed fiber optics, more detailed mode shapes could be obtained. In order to test the effectiveness of the method, a mass lump—considered as a linear damage component—has been attached to the surface of the beam, and damage detection based on strain mode shape has been carried out. The results manifest that strain modal parameters can be estimated effectively by utilizing the CMIF based on the corresponding simulations and experiments. Furthermore, damage detection based on strain mode shapes benefits from the accuracy of strain mode shape recognition and the excellent performance of the distributed fiber optics.

Modalities of memory: is reading lips like hearing voices?

PubMed

Maidment, David W; Macken, Bill; Jones, Dylan M

2013-12-01

Functional similarities in verbal memory performance across presentation modalities (written, heard, lipread) are often taken to point to a common underlying representational form upon which the modalities converge. We show here instead that the pattern of performance depends critically on presentation modality and different mechanisms give rise to superficially similar effects across modalities. Lipread recency is underpinned by different mechanisms to auditory recency, and while the effect of an auditory suffix on an auditory list is due to the perceptual grouping of the suffix with the list, the corresponding effect with lipread speech is due to misidentification of the lexical content of the lipread suffix. Further, while a lipread suffix does not disrupt auditory recency, an auditory suffix does disrupt recency for lipread lists. However, this effect is due to attentional capture ensuing from the presentation of an unexpected auditory event, and is evident both with verbal and nonverbal auditory suffixes. These findings add to a growing body of evidence that short-term verbal memory performance is determined by modality-specific perceptual and motor processes, rather than by the storage and manipulation of phonological representations. Copyright © 2013 Elsevier B.V. All rights reserved.

Factors of Influence on the Performance of a Short-Latency Non-Invasive Brain Switch: Evidence in Healthy Individuals and Implication for Motor Function Rehabilitation

PubMed Central

Xu, Ren; Jiang, Ning; Mrachacz-Kersting, Natalie; Dremstrup, Kim; Farina, Dario

2016-01-01

Brain-computer interfacing (BCI) has recently been applied as a rehabilitation approach for patients with motor disorders, such as stroke. In these closed-loop applications, a brain switch detects the motor intention from brain signals, e.g., scalp EEG, and triggers a neuroprosthetic device, either to deliver sensory feedback or to mimic real movements, thus re-establishing the compromised sensory-motor control loop and promoting neural plasticity. In this context, single trial detection of motor intention with short latency is a prerequisite. The performance of the event detection from EEG recordings is mainly determined by three factors: the type of motor imagery (e.g., repetitive, ballistic), the frequency band (or signal modality) used for discrimination (e.g., alpha, beta, gamma, and MRCP, i.e., movement-related cortical potential), and the processing technique (e.g., time-series analysis, sub-band power estimation). In this study, we investigated single trial EEG traces during movement imagination on healthy individuals, and provided a comprehensive analysis of the performance of a short-latency brain switch when varying these three factors. The morphological investigation showed a cross-subject consistency of a prolonged negative phase in MRCP, and a delayed beta rebound in sensory-motor rhythms during repetitive tasks. The detection performance had the greatest accuracy when using ballistic MRCP with time-series analysis. In this case, the true positive rate (TPR) was ~70% for a detection latency of ~200 ms. The results presented here are of practical relevance for designing BCI systems for motor function rehabilitation. PMID:26834551

The Role of Task-Related Learned Representations in Explaining Asymmetries in Task Switching

PubMed Central

Barutchu, Ayla; Becker, Stefanie I.; Carter, Olivia; Hester, Robert; Levy, Neil L.

2013-01-01

Task switch costs often show an asymmetry, with switch costs being larger when switching from a difficult task to an easier task. This asymmetry has been explained by difficult tasks being represented more strongly and consequently requiring more inhibition prior to switching to the easier task. The present study shows that switch cost asymmetries observed in arithmetic tasks (addition vs. subtraction) do not depend on task difficulty: Switch costs of similar magnitudes were obtained when participants were presented with unsolvable pseudo-equations that did not differ in task difficulty. Further experiments showed that neither task switch costs nor switch cost asymmetries were due to perceptual factors (e.g., perceptual priming effects). These findings suggest that asymmetrical switch costs can be brought about by the association of some tasks with greater difficulty than others. Moreover, the finding that asymmetrical switch costs were observed (1) in the absence of a task switch proper and (2) without differences in task difficulty, suggests that present theories of task switch costs and switch cost asymmetries are in important ways incomplete and need to be modified. PMID:23613919

Cross-modal and modality-specific expectancy effects between pain and disgust

PubMed Central

Sharvit, Gil; Vuilleumier, Patrik; Delplanque, Sylvain; Corradi-Dell’ Acqua, Corrado

2015-01-01

Pain sensitivity increases when a noxious stimulus is preceded by cues predicting higher intensity. However, it is unclear whether the modulation of nociception by expectancy is sensory-specific (“modality based”) or reflects the aversive-affective consequence of the upcoming event (“unpleasantness”), potentially common with other negative events. Here we compared expectancy effects for pain and disgust by using different, but equally unpleasant, nociceptive (thermal) and olfactory stimulations. Indeed both pain and disgust are aversive, associated with threat to the organism, and processed in partly overlapping brain networks. Participants saw cues predicting the unpleasantness (high/low) and the modality (pain/disgust) of upcoming thermal or olfactory stimulations, and rated the associated unpleasantness after stimuli delivery. Results showed that identical thermal stimuli were perceived as more unpleasant when preceded by cues threatening about high (as opposed to low) pain. A similar expectancy effect was found for olfactory disgust. Critically, cross-modal expectancy effects were observed on inconsistent trials when thermal stimuli were preceded by high-disgust cues or olfactory stimuli preceded by high-pain cues. However, these effects were stronger in consistent than inconsistent conditions. Taken together, our results suggest that expectation of an unpleasant event elicits representations of both its modality-specific properties and its aversive consequences. PMID:26631975

The taste-visual cross-modal Stroop effect: An event-related brain potential study.

PubMed

Xiao, X; Dupuis-Roy, N; Yang, X L; Qiu, J F; Zhang, Q L

2014-03-28

Event-related potentials (ERPs) were recorded to explore, for the first time, the electrophysiological correlates of the taste-visual cross-modal Stroop effect. Eighteen healthy participants were presented with a taste stimulus and a food image, and asked to categorize the image as "sweet" or "sour" by pressing the relevant button as quickly as possible. Accurate categorization of the image was faster when it was presented with a congruent taste stimulus (e.g., sour taste/image of lemon) than with an incongruent one (e.g., sour taste/image of ice cream). ERP analyses revealed a negative difference component (ND430-620) between 430 and 620ms in the taste-visual cross-modal Stroop interference. Dipole source analysis of the difference wave (incongruent minus congruent) indicated that two generators localized in the prefrontal cortex and the parahippocampal gyrus contributed to this taste-visual cross-modal Stroop effect. This result suggests that the prefrontal cortex is associated with the process of conflict control in the taste-visual cross-modal Stroop effect. Also, we speculate that the parahippocampal gyrus is associated with the process of discordant information in the taste-visual cross-modal Stroop effect. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Multisensory perception of the six basic emotions is modulated by attentional instruction and unattended modality

PubMed Central

Takagi, Sachiko; Hiramatsu, Saori; Tabei, Ken-ichi; Tanaka, Akihiro

2015-01-01

Previous studies have shown that the perception of facial and vocal affective expressions interacts with each other. Facial expressions usually dominate vocal expressions when we perceive the emotions of face–voice stimuli. In most of these studies, participants were instructed to pay attention to the face or voice. Few studies compared the perceived emotions with and without specific instructions regarding the modality to which attention should be directed. Also, these studies used combinations of the face and voice which expresses two opposing emotions, which limits the generalizability of the findings. The purpose of this study is to examine whether the emotion perception is modulated by instructions to pay attention to the face or voice using the six basic emotions. Also we examine the modality dominance between the face and voice for each emotion category. Before the experiment, we recorded faces and voices which expresses the six basic emotions and orthogonally combined these faces and voices. Consequently, the emotional valence of visual and auditory information was either congruent or incongruent. In the experiment, there were unisensory and multisensory sessions. The multisensory session was divided into three blocks according to whether an instruction was given to pay attention to a given modality (face attention, voice attention, and no instruction). Participants judged whether the speaker expressed happiness, sadness, anger, fear, disgust, or surprise. Our results revealed that instructions to pay attention to one modality and congruency of the emotions between modalities modulated the modality dominance, and the modality dominance is differed for each emotion category. In particular, the modality dominance for anger changed according to each instruction. Analyses also revealed that the modality dominance suggested by the congruency effect can be explained in terms of the facilitation effect and the interference effect. PMID:25698945

How to Correct a Task Error: Task-Switch Effects Following Different Types of Error Correction

ERIC Educational Resources Information Center

Steinhauser, Marco

2010-01-01

It has been proposed that switch costs in task switching reflect the strengthening of task-related associations and that strengthening is triggered by response execution. The present study tested the hypothesis that only task-related responses are able to trigger strengthening. Effects of task strengthening caused by error corrections were…

Switch-On Effectiveness Trial: Evaluation Report and Executive Summary

ERIC Educational Resources Information Center

Patel, Rakhee; Jabin, Nico; Bussard, Loraine; Cartagena, Javiera; Haywood, Sarah; Lumpkin, Michael

2017-01-01

Switch-on is an intensive, targeted literacy intervention that aims to improve the reading skills of pupils who are struggling with literacy. There are two versions of the intervention: Switch-on Reading and Switch-on Reading and Writing. Both involve specially trained Teaching Assistants (TAs) delivering a tailored programme of literacy support…

Optically controlled redshift switching effects in hybrid fishscale metamaterials

NASA Astrophysics Data System (ADS)

Wang, Yu; Zhu, Jinwei; Zhang, Hao; Zhang, Wenxing; Dong, Guohua; Ye, Peng; Lv, Tingting; Zhu, Zheng; Li, Yuxiang; Guan, Chunying; Shi, Jinhui

2018-05-01

We numerically demonstrate optically controlled THz response in a hybrid fishscale metamaterial with embedded photoconductive silicon at oblique incidence of TE wave. The oblique incidence allows excitation of Fano-type trapped mode resonance in a 2-fold rotational symmetric metamaterial. The hybrid fishscale metamaterial exhibits an optically controlled redshift switching effect in the THz range. The switching effect is dominated by the conductivity of the silicon instead of mechanically adjusting angles of incidence. The tuning frequency range is up to 0.3THz with a large modulation depth and high transmission in the "ON" state. The fishscale metamaterial-based switching has been experimentally verified by its microwave counterpart integrated by variable resistors. Our work provides an alternative route to realize tunable Fano-type response in metamaterials and is of importance to active manipulation, sensing and switching of THz waves in practical applications.

Transient Response of Shells of Revolution by Direct Integration and Modal Superposition Methods

NASA Technical Reports Server (NTRS)

Stephens, W. B.; Adelman, H. M.

1974-01-01

The results of an analytical effort to obtain and evaluate transient response data for a cylindrical and a conical shell by use of two different approaches: direct integration and modal superposition are described. The inclusion of nonlinear terms is more important than the inclusion of secondary linear effects (transverse shear deformation and rotary inertia) although there are thin-shell structures where these secondary effects are important. The advantages of the direct integration approach are that geometric nonlinear and secondary effects are easy to include and high-frequency response may be calculated. In comparison to the modal superposition technique the computer storage requirements are smaller. The advantages of the modal superposition approach are that the solution is independent of the previous time history and that once the modal data are obtained, the response for repeated cases may be efficiently computed. Also, any admissible set of initial conditions can be applied.

A wide-angle high Mach number modal expansion for infrasound propagation.

PubMed

Assink, Jelle; Waxler, Roger; Velea, Doru

2017-03-01

The use of modal expansions to solve the problem of atmospheric infrasound propagation is revisited. A different form of the associated modal equation is introduced, valid for wide-angle propagation in atmospheres with high Mach number flow. The modal equation can be formulated as a quadratic eigenvalue problem for which there are simple and efficient numerical implementations. A perturbation expansion for the treatment of attenuation, valid for stratified media with background flow, is derived as well. Comparisons are carried out between the proposed algorithm and a modal algorithm assuming an effective sound speed, including a real data case study. The comparisons show that the effective sound speed approximation overestimates the effect of horizontal wind on sound propagation, leading to errors in traveltime, propagation path, trace velocity, and absorption. The error is found to be dependent on propagation angle and Mach number.

Outreach in the Delivery of Mental Health Services to Hispanic Elders.

ERIC Educational Resources Information Center

Szapocznik, Jose; And Others

1979-01-01

The study investigated the effectiveness of two outreach/education modalities established to increase the utilization of mental health services by Hispanic elders: (1) a service delivery modality, and (2) a mass media modality. (NQ)

Cross-modal representation of spoken and written word meaning in left pars triangularis.

PubMed

Liuzzi, Antonietta Gabriella; Bruffaerts, Rose; Peeters, Ronald; Adamczuk, Katarzyna; Keuleers, Emmanuel; De Deyne, Simon; Storms, Gerrit; Dupont, Patrick; Vandenberghe, Rik

2017-04-15

The correspondence in meaning extracted from written versus spoken input remains to be fully understood neurobiologically. Here, in a total of 38 subjects, the functional anatomy of cross-modal semantic similarity for concrete words was determined based on a dual criterion: First, a voxelwise univariate analysis had to show significant activation during a semantic task (property verification) performed with written and spoken concrete words compared to the perceptually matched control condition. Second, in an independent dataset, in these clusters, the similarity in fMRI response pattern to two distinct entities, one presented as a written and the other as a spoken word, had to correlate with the similarity in meaning between these entities. The left ventral occipitotemporal transition zone and ventromedial temporal cortex, retrosplenial cortex, pars orbitalis bilaterally, and the left pars triangularis were all activated in the univariate contrast. Only the left pars triangularis showed a cross-modal semantic similarity effect. There was no effect of phonological nor orthographic similarity in this region. The cross-modal semantic similarity effect was confirmed by a secondary analysis in the cytoarchitectonically defined BA45. A semantic similarity effect was also present in the ventral occipital regions but only within the visual modality, and in the anterior superior temporal cortex only within the auditory modality. This study provides direct evidence for the coding of word meaning in BA45 and positions its contribution to semantic processing at the confluence of input-modality specific pathways that code for meaning within the respective input modalities. Copyright © 2017 Elsevier Inc. All rights reserved.

A comparison of "Train-the-Trainer" and expert training modalities for hearing protection use in construction.

PubMed

Trabeau, Maggie; Neitzel, Richard; Meischke, Hendrika; Daniell, William E; Seixas, Noah S

2008-02-01

Few assessments have been conducted on the impact of a "Train-the-Trainer" (T3) approach for training delivery. The present study compared the effectiveness of a noise induced hearing loss (NIHL) prevention training delivered using "Train-the-Trainer" and expert trainer modalities. Participating construction companies were assigned to the Train-the-Trainer or expert trainer modalities. Workers were recruited from each company and then trained. The effectiveness of the modalities was assessed through the use of surveys. The accuracy of self-reported hearing protection device (HPD) use was also evaluated through on-site observation. Post-training scores for hearing conservation knowledge, perceived barriers, and current and intended future use of HPDs improved significantly for both training modalities. Subjects trained by T3 trainers significantly increased their beliefs regarding general susceptibility to NIHL, desire to prevent NIHL, and ability to recognize, and control hazardous noise exposures. The expert-trained groups significantly increased their beliefs regarding the benefits of HPD use and ability to ask for help with HPDs. The only changes that were significantly different between modalities were in general susceptibility to NIHL and effective use of HPDs. However, these beliefs differed significantly between subjects in the two-modality groups prior to training. Self-reported HPD use was poorly correlated with observed use, calling into question the validity of survey-based HPD use measures in this context. The training improved beliefs regarding HPD use, increased workers' hearing conservation knowledge, and increased self-reported HPD use. The effectiveness of the training was not found to be dependent on training modality.

Switching long acting antipsychotic medications to aripiprazole long acting once-a-month: expert consensus by a panel of Italian and Spanish psychiatrists.

PubMed

Fagiolini, Andrea; Alfonsi, Emilia; Amodeo, Giovanni; Cenci, Mario; Di Lella, Michele; Farinella, Francesco; Ferraiuolo, Fabrizio; Fraguas, David; Loparco, Natale; Gutierrez-Rojas, Luis; Mignone, Maria Laura; Pataracchia, Giuseppe; Pillai, Gianluca; Russo, Felicia; Sanchez-Gistau, Vanessa; Spinogatti, Franco; Toscano, Marco; Villari, Vincenzo; De Filippis, Sergio

2016-01-01

Aripiprazole long acting once-monthly (AOM) is a long acting atypical antipsychotic with proven efficacy in schizophrenia and with a pharmacological and a side effect profile that is different from other antipsychotics. These and other characteristics make AOM a possible alternative in patients requiring a change in long acting antipsychotic treatment due to issues such as lack of efficacy or persistent side effects. Both clinical and pharmacological factors should be considered when switching antipsychotics, and specific guidelines for long acting antipsychotic switching that address all these factors are needed. A panel of Italian and Spanish experts in psychiatry met to discuss the strategies for the switch to AOM in patients with schizophrenia. Real life clinical experiences were shared and the clinical strategies to improve the likelihood of success were discussed. Due to its specific pharmacological and tolerability profile, AOM represents a suitable alternative for patients with schizophrenia requiring a switch to a new LAI treatment because of lack of efficacy or persistent side effects from another LAI. Possible strategies for the switch to AOM are presented in this expert consensus paper in an attempt to provide guidance throughout the entire switching process.

Switching antipsychotic medications.

PubMed

Weiden, P J; Aquila, R; Dalheim, L; Standard, J M

1997-01-01

Compared with conventional antipsychotics, the so-called "atypical" antipsychotics promise improved side effect profiles and better control of the symptoms of schizophrenia. Therefore, most patients currently taking conventional antipsychotics could potentially benefit from a switch to an atypical antipsychotic. Often, the key issue in deciding whether to switch is the presence of countervailing factors that mitigate against the change. This paper discusses the indications and contraindications for switching antipsychotics, plus issues that require consideration before a switch is made. Also, the advantages and disadvantages of various switching techniques are discussed, with a particular focus on the newer antipsychotic olanzapine.

Cost-effective optical switch matrix for microwave phased-array

NASA Technical Reports Server (NTRS)

Pan, J. J.; Chia, S. L.; Li, W. Z.; Grove, C. H.

1991-01-01

An all-fiber (6x6) optical shutter switch matrix with the control system for microwave phased array has been demonstrated. The device offers the advantages of integrated configuration, low cost, low power consumption, small size, and light weight. The maximum extinction ratio (among 36 individual pixel) of this switch matrix at 840 nm is 24.2 dB, and the switching time is less than 120 microsec. In addition to phased array application, this low cost switch matrix is extremely attractive for fiber optic switching networks.

Letter position coding across modalities: the case of Braille readers.

PubMed

Perea, Manuel; García-Chamorro, Cristina; Martín-Suesta, Miguel; Gómez, Pablo

2012-01-01

The question of how the brain encodes letter position in written words has attracted increasing attention in recent years. A number of models have recently been proposed to accommodate the fact that transposed-letter stimuli like jugde or caniso are perceptually very close to their base words. Here we examined how letter position coding is attained in the tactile modality via Braille reading. The idea is that Braille word recognition may provide more serial processing than the visual modality, and this may produce differences in the input coding schemes employed to encode letters in written words. To that end, we conducted a lexical decision experiment with adult Braille readers in which the pseudowords were created by transposing/replacing two letters. We found a word-frequency effect for words. In addition, unlike parallel experiments in the visual modality, we failed to find any clear signs of transposed-letter confusability effects. This dissociation highlights the differences between modalities. The present data argue against models of letter position coding that assume that transposed-letter effects (in the visual modality) occur at a relatively late, abstract locus.

Aging and the visual, haptic, and cross-modal perception of natural object shape.

PubMed

Norman, J Farley; Crabtree, Charles E; Norman, Hideko F; Moncrief, Brandon K; Herrmann, Molly; Kapley, Noah

2006-01-01

One hundred observers participated in two experiments designed to investigate aging and the perception of natural object shape. In the experiments, younger and older observers performed either a same/different shape discrimination task (experiment 1) or a cross-modal matching task (experiment 2). Quantitative effects of age were found in both experiments. The effect of age in experiment 1 was limited to cross-modal shape discrimination: there was no effect of age upon unimodal (ie within a single perceptual modality) shape discrimination. The effect of age in experiment 2 was eliminated when the older observers were either given an unlimited amount of time to perform the task or when the number of response alternatives was decreased. Overall, the results of the experiments reveal that older observers can effectively perceive 3-D shape from both vision and haptics.

Comparison of HELIX TWT Simulation Using 2-D PIC (Magic), 2-D Modal (Gator), and 1-D Modal (Christine) Methods

DTIC Science & Technology

1998-05-01

Mission Research Corporation MRC/WDC-R-424 COMPARISON OF HELIX TWT SIMULATION USING 2-D PIC ( MAGIC ), 2-D MODAL (GATOR), AND 1-D MODAL (CHRISTINE...BRILLOUIN RUN 9 3.4 OUTLIER ELECTRON EFFECT IN GATOR 12 3.5 EMISSION CONDITION AND NONLAMINAR FLOW IN MAGIC 12 3.6 RADIAL SHEAR 13 SECTION 4. PPM B...Simulation using 2-D PIC ( MAGIC ), 2-D Modal (GATOR) and 1-D Modal (CHRISTINE) methods * D.N. Smithe(a), H. Freund(b), T. M. Antonsen Jr.,(b)’(c), E

Scaling Effect on Unipolar and Bipolar Resistive Switching of Metal Oxides

PubMed Central

Yanagida, Takeshi; Nagashima, Kazuki; Oka, Keisuke; Kanai, Masaki; Klamchuen, Annop; Park, Bae Ho; Kawai, Tomoji

2013-01-01

Electrically driven resistance change in metal oxides opens up an interdisciplinary research field for next-generation non-volatile memory. Resistive switching exhibits an electrical polarity dependent “bipolar-switching” and a polarity independent “unipolar-switching”, however tailoring the electrical polarity has been a challenging issue. Here we demonstrate a scaling effect on the emergence of the electrical polarity by examining the resistive switching behaviors of Pt/oxide/Pt junctions over 8 orders of magnitudes in the areas. We show that the emergence of two electrical polarities can be categorised as a diagram of an electric field and a cell area. This trend is qualitatively common for various oxides including NiOx, CoOx, and TiO2-x. We reveal the intrinsic difference between unipolar switching and bipolar switching on the area dependence, which causes a diversity of an electrical polarity for various resistive switching devices with different geometries. This will provide a foundation for tailoring resistive switching behaviors of metal oxides. PMID:23584551

Voltage-Controlled Switching and Thermal Effects in VO2 Nano-Gap Junctions

DTIC Science & Technology

2014-06-09

Voltage-controlled switching and thermal effects in VO2 nano-gap junctions Arash Joushaghani,1 Junho Jeong,1 Suzanne Paradis,2 David Alain,2 J...2014) Voltage-controlled switching in lateral VO2 nano-gap junctions with different gap lengths and thermal properties was investigated. The effect of...indicate that the VO2 phase transition was likely initiated electroni- cally, which was sometimes followed by a secondary thermally-induced transition

Effect of biquadratic coupling on current induced magnetization switching in Co/Cu/Ni-Fe nanopillar

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

Aravinthan, D.; Daniel, M., E-mail: danielcnld@gmail.com; Sabareesan, P.

2016-05-23

The effect of biquadratic coupling on spin current induced magnetization switching in a Co/Cu/Ni-Fe nanopillar device is investigated by solving the free layer magnetization switching dynamics governed by the Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation. The LLGS equation is numerically solved by using Runge-Kutta fourth order procedure for an applied current density of 5 × 10{sup 12} Am{sup -2}. Presence of biquadratic coupling in the ferromagnetic layers reduces the magnetization switching time of the nanopillar device from 61 ps to 49 ps.

The effects of presentation pace and modality on learning a multimedia science lesson

NASA Astrophysics Data System (ADS)

Chung, Wen-Hung

Working memory is a system that consists of multiple components. The visuospatial sketchpad is the main entrance for visual and spatial information, whereas acoustic and verbal information is processed in the phonological loop. The central executive works as a coordinator of information from these two subsystems. Numerous studies have shown that working memory has a very limited capacity. Based on these characteristics of working memory, theories such as cognitive load theory and the cognitive theory of multimedia learning provide multimedia design principles. One of these principles is that when verbal information accompanying pictures is presented in audio mode instead of visually, learning can be more effective than if both text and pictures are presented visually. This is called the modality effect. However, some studies have found that the modality effect does not occur in some situations. In most experiments examining the modality effect, the multimedia is presented as system-paced. If learners are able to repeat listening as many times as they need, the superiority of spoken text over visual text seems lessened. One aim of this study was to examine the modality effect in a learner-controlled condition. This study also used the one-word-at-a-time technique to investigate whether the modality effect would still occur if both reading and listening rates were equal. There were 182 college students recruited for this study. Participants were randomly assigned to seven groups: a self-paced listening group, a self-paced reading group, a self text-block reading group, a general-paced listening group, a general-paced reading group, a fast-paced listening group, and a fast-paced reading group. The experimental material was a cardiovascular multimedia module. A three-by-two between-subjects design was used to test the main effect. Results showed that modality effect was still present but not between the self-paced listening group and the self text-block reading group. A post-study survey showed participants' different responses to the two modalities and their preferences as well. Results and research limitations are discussed and applications and future directions are also addressed.

Predictors of treatment with dialysis modalities in observational studies for comparative effectiveness research*

PubMed Central

Kuttykrishnan, Sooraj; Kalantar-Zadeh, Kamyar; Arah, Onyebuchi A.; Cheung, Alfred K.; Brunelli, Steve; Heagerty, Patrick J.; Katz, Ronit; Molnar, Miklos Z.; Nissenson, Allen; Ravel, Vanessa; Streja, Elani; Himmelfarb, Jonathan; Mehrotra, Rajnish

2015-01-01

Background The Institute of Medicine has identified the comparative effectiveness of renal replacement therapies as a kidney-related topic among the top 100 national priorities. Given the importance of ensuring internal and external validity, the goal of this study was to identify potential sources of bias in observational studies that compare outcomes with different dialysis modalities. Methods This observational cohort study used data from the electronic medical records of all patients that started maintenance dialysis in the calendar years 2007–2011 and underwent treatment for at least 60 days in any of the 2217 facilities operated by DaVita Inc. Each patient was assigned one of six dialysis modalities for each 91-day period from the date of first dialysis (thrice weekly in-center hemodialysis (HD), peritoneal dialysis (PD), less-frequent HD, home HD, frequent HD and nocturnal in-center HD). Results Of the 162 644 patients, 18% underwent treatment with a modality other than HD for at least one 91-day period. Except for PD, patients started treatment with alternative modalities after variable lengths of treatment with HD; the time until a change in modality was shortest for less-frequent HD (median time = 6 months) and longest for frequent HD (median time = 15 months). Between 30 and 78% of patients transferred to another dialysis facility prior to change in modality. Finally, there were significant differences in baseline and time-varying clinical characteristics associated with dialysis modality. Conclusions This analysis identified numerous potential sources of bias in studies of the comparative effectiveness of dialysis modalities. PMID:25883196

Distributed Consensus of Stochastic Delayed Multi-agent Systems Under Asynchronous Switching.

PubMed

Wu, Xiaotai; Tang, Yang; Cao, Jinde; Zhang, Wenbing

2016-08-01

In this paper, the distributed exponential consensus of stochastic delayed multi-agent systems with nonlinear dynamics is investigated under asynchronous switching. The asynchronous switching considered here is to account for the time of identifying the active modes of multi-agent systems. After receipt of confirmation of mode's switching, the matched controller can be applied, which means that the switching time of the matched controller in each node usually lags behind that of system switching. In order to handle the coexistence of switched signals and stochastic disturbances, a comparison principle of stochastic switched delayed systems is first proved. By means of this extended comparison principle, several easy to verified conditions for the existence of an asynchronously switched distributed controller are derived such that stochastic delayed multi-agent systems with asynchronous switching and nonlinear dynamics can achieve global exponential consensus. Two examples are given to illustrate the effectiveness of the proposed method.

Switch Detection in Preschoolers' Cognitive Flexibility

ERIC Educational Resources Information Center

Chevalier, Nicolas; Wiebe, Sandra A.; Huber, Kristina L.; Espy, Kimberly Andrews

2011-01-01

The current study addressed the role of switch detection in cognitive flexibility by testing the effect of transition cues (i.e., cues that directly signal the need to switch or maintain a given task goal) in a cued set-shifting paradigm at 5 years of age. Children performed better, especially on switch trials, when transition cues were combined…

Numerical Investigation on Detection of Prestress Losses in a Prestressed Concrete Slab by Modal Analysis

NASA Astrophysics Data System (ADS)

Kovalovs, A.; Rucevskis, S.; Akishin, P.; Kolupajevs, J.

2017-10-01

The paper presents numerical results of loss of prestress in the reinforced prestressed precast hollow core slabs by modal analysis. Loss of prestress is investigated by the 3D finite element method, using ANSYS software. In the numerical examples, variables initial stresses were introduced into seven-wire stress-relieved strands of the concrete slabs. The effects of span and material properties of concrete on the modal frequencies of the concrete structure under initial stress were studied. Modal parameters computed from the finite element models were compared. Applicability and effectiveness of the proposed method was investigated.

Contact effects in light activated GaAs switches

NASA Astrophysics Data System (ADS)

Durkin, P. S.

1985-05-01

The purpose of this work was to examine the effects of various types of contacts on the switching behavior of a light-triggered power switch. The switch was constructed from a homogeneous wafer of chromium-doped gallium arsenide; the contacts were either ohmic, non-ohmic, or Schottky barriers. These were formed on the wafer in two geometries; both contacts on one side, and one contact spacings were used to permit the effects of the location of the existing laser pulse to be studied. A high voltage power supply (zero to 20 kV) was employed as the bias supply. A Nd:YAG laser, in the pulsed mode, was used to trigger the switch, which was mounted on a cold finger cooled to near liquid nitrogen temperature. Cooling reduced the dark current to manageable values (less than 1 micro A), and also reduced the avalanche breakdown voltage. The results of the measurements indicate that ohmic contacts produced more reliable switching than the non-ohmic or Schottky contacts, in as much as the shape of the output current pulse was better, and the number of pulses which the switches could sustain before the pulse shape deteriorated was greater, for the ohmic contacts. Surface discharge between the one-sided contacts obscured any differences in switching characteristics which might have depended on the location of the pulsed light excitation, so that no correlation between position and behavior could be obtained.

Analog self-powered harvester achieving switching pause control to increase harvested energy

NASA Astrophysics Data System (ADS)

Makihara, Kanjuro; Asahina, Kei

2017-05-01

In this paper, we propose a self-powered analog controller circuit to increase the efficiency of electrical energy harvesting from vibrational energy using piezoelectric materials. Although the existing synchronized switch harvesting on inductor (SSHI) method is designed to produce efficient harvesting, its switching operation generates a vibration-suppression effect that reduces the harvested levels of electrical energy. To solve this problem, the authors proposed—in a previous paper—a switching method that takes this vibration-suppression effect into account. This method temporarily pauses the switching operation, allowing the recovery of the mechanical displacement and, therefore, of the piezoelectric voltage. In this paper, we propose a self-powered analog circuit to implement this switching control method. Self-powered vibration harvesting is achieved in this study by attaching a newly designed circuit to an existing analog controller for SSHI. This circuit aims to effectively implement the aforementioned new switching control strategy, where switching is paused in some vibration peaks, in order to allow motion recovery and a consequent increase in the harvested energy. Harvesting experiments performed using the proposed circuit reveal that the proposed method can increase the energy stored in the storage capacitor by a factor of 8.5 relative to the conventional SSHI circuit. This proposed technique is useful to increase the harvested energy especially for piezoelectric systems having large coupling factor.

How many training modalities are needed to obtain procedural confidence in intraosseous access? A questionnaire study.

PubMed

Hallas, Peter; Folkestad, Lars; Brabrand, Mikkel

2011-12-01

Participants in advanced resuscitation courses are often expected to learn to perform intraosseous access (IO). But how many learning modalities are needed to achieve procedural confidence in IO? We distributed an online questionnaire to members of emergency medicine, paediatric and anaesthesiology societies in Scandinavia. The responders without real-life experience with IO (n=322) were classified as 'not confident' or 'confident' in IO. Of total responders 22.8% without training felt confident. Confidence increased to 74.8% after one training modality, 87.9% after two modalities, 98.7% after three modalities and 100% after four modalities (P<0.0001). Of total responders 89.5% who had 'workshop or similar training with hands-on experience' as sole teaching method was confident. Confidence in IO increases with the number of learning modalities. 'Workshop or similar training with hands-on experience' as single training modality seemed as effective as the combination of two modalities.

Learning Across Senses: Cross-Modal Effects in Multisensory Statistical Learning

PubMed Central

Mitchel, Aaron D.; Weiss, Daniel J.

2014-01-01

It is currently unknown whether statistical learning is supported by modality-general or modality-specific mechanisms. One issue within this debate concerns the independence of learning in one modality from learning in other modalities. In the present study, the authors examined the extent to which statistical learning across modalities is independent by simultaneously presenting learners with auditory and visual streams. After establishing baseline rates of learning for each stream independently, they systematically varied the amount of audiovisual correspondence across 3 experiments. They found that learners were able to segment both streams successfully only when the boundaries of the audio and visual triplets were in alignment. This pattern of results suggests that learners are able to extract multiple statistical regularities across modalities provided that there is some degree of cross-modal coherence. They discuss the implications of their results in light of recent claims that multisensory statistical learning is guided by modality-independent mechanisms. PMID:21574745

Impact analysis of tap switch out of step for converter transformer

NASA Astrophysics Data System (ADS)

Hong-yue, ZHANG; Zhen-hua, ZHANG; Zhang-xue, XIONG; Gao-wang, YU

2017-06-01

AC transformer load regulation is mainly used to adjust the load side voltage level, improve the quality of power supply, the voltage range is relatively narrow. In DC system, converter transformer is the core equipment of AC and DC power converter and inverter. converter transformer tap adjustment can maintain the normal operation of the converter in small angle range control, the absorption of reactive power, economic operation, valve less stress, valve damping circuit loss, AC / DC harmonic component is also smaller. In this way, the tap switch action is more frequent, and a large range of the tap switch adjustment is required. Converter transformer with a more load voltage regulation switch, the voltage regulation range of the switch is generally 20~30%, the adjustment of each file is 1%~2%. Recently it is often found that the tap switch of Converter Transformers is out of step in Converter station. In this paper, it is analyzed in detail the impact of tap switch out of step for differential protection, overexcitation protection and zero sequence over current protection. Analysis results show that: the tap switch out of step has no effect on the differential protection and the overexcitation protection including the tap switch. But the tap switch out of step has effect on zero sequence overcurrent protection of out of step star-angle converter transformer. The zero sequence overcurrent protection will trip when the tap switch out of step is greater than 3 for out of step star-angle converter transformer.

Systematic Genetic Screen for Transcriptional Regulators of the Candida albicans White-Opaque Switch.

PubMed

Lohse, Matthew B; Ene, Iuliana V; Craik, Veronica B; Hernday, Aaron D; Mancera, Eugenio; Morschhäuser, Joachim; Bennett, Richard J; Johnson, Alexander D

2016-08-01

The human fungal pathogen Candida albicans can reversibly switch between two cell types named "white" and "opaque," each of which is stable through many cell divisions. These two cell types differ in their ability to mate, their metabolic preferences and their interactions with the mammalian innate immune system. A highly interconnected network of eight transcriptional regulators has been shown to control switching between these two cell types. To identify additional regulators of the switch, we systematically and quantitatively measured white-opaque switching rates of 196 strains, each deleted for a specific transcriptional regulator. We identified 19 new regulators with at least a 10-fold effect on switching rates and an additional 14 new regulators with more subtle effects. To investigate how these regulators affect switching rates, we examined several criteria, including the binding of the eight known regulators of switching to the control region of each new regulatory gene, differential expression of the newly found genes between cell types, and the growth rate of each mutant strain. This study highlights the complexity of the transcriptional network that regulates the white-opaque switch and the extent to which switching is linked to a variety of metabolic processes, including respiration and carbon utilization. In addition to revealing specific insights, the information reported here provides a foundation to understand the highly complex coupling of white-opaque switching to cellular physiology. Copyright © 2016 by the Genetics Society of America.

Early auditory change detection implicitly facilitated by ignored concurrent visual change during a Braille reading task.

PubMed

Aoyama, Atsushi; Haruyama, Tomohiro; Kuriki, Shinya

2013-09-01

Unconscious monitoring of multimodal stimulus changes enables humans to effectively sense the external environment. Such automatic change detection is thought to be reflected in auditory and visual mismatch negativity (MMN) and mismatch negativity fields (MMFs). These are event-related potentials and magnetic fields, respectively, evoked by deviant stimuli within a sequence of standard stimuli, and both are typically studied during irrelevant visual tasks that cause the stimuli to be ignored. Due to the sensitivity of MMN/MMF to potential effects of explicit attention to vision, however, it is unclear whether multisensory co-occurring changes can purely facilitate early sensory change detection reciprocally across modalities. We adopted a tactile task involving the reading of Braille patterns as a neutral ignore condition, while measuring magnetoencephalographic responses to concurrent audiovisual stimuli that were infrequently deviated either in auditory, visual, or audiovisual dimensions; 1000-Hz standard tones were switched to 1050-Hz deviant tones and/or two-by-two standard check patterns displayed on both sides of visual fields were switched to deviant reversed patterns. The check patterns were set to be faint enough so that the reversals could be easily ignored even during Braille reading. While visual MMFs were virtually undetectable even for visual and audiovisual deviants, significant auditory MMFs were observed for auditory and audiovisual deviants, originating from bilateral supratemporal auditory areas. Notably, auditory MMFs were significantly enhanced for audiovisual deviants from about 100 ms post-stimulus, as compared with the summation responses for auditory and visual deviants or for each of the unisensory deviants recorded in separate sessions. Evidenced by high tactile task performance with unawareness of visual changes, we conclude that Braille reading can successfully suppress explicit attention and that simultaneous multisensory changes can implicitly strengthen automatic change detection from an early stage in a cross-sensory manner, at least in the vision to audition direction.

Method to optimize optical switch topology for photonic network-on-chip

NASA Astrophysics Data System (ADS)

Zhou, Ting; Jia, Hao

2018-04-01

In this paper, we propose a method to optimize the optical switch by substituting optical waveguide crossings for optical switching units and an optimizing algorithm to complete the optimization automatically. The functionality of the optical switch remains constant under optimization. With this method, we simplify the topology of optical switch, which means the insertion loss and power consumption of the whole optical switch can be effectively minimized. Simulation result shows that the number of switching units of the optical switch based on Spanke-Benes can be reduced by 16.7%, 20%, 20%, 19% and 17.9% for the scale from 4 × 4 to 8 × 8 respectively. As a proof of concept, the experimental demonstration of an optimized six-port optical switch based on Spanke-Benes structure by means of silicon photonics chip is reported.

Task switching and response correspondence in the psychological refractory period paradigm

NASA Technical Reports Server (NTRS)

Lien, Mei-Ching; Schweickert, Richard; Proctor, Robert W.

2003-01-01

Three experiments examined the effects of task switching and response correspondence in a psychological refractory period paradigm. A letter task (vowel-consonant) and a digit task (odd-even) were combined to form 4 possible dual-task pairs in each trial: letter-letter, letter-digit, digit-digit, and digit-letter. Foreknowledge of task transition (repeat or switch) and task identity (letter or digit) was varied across experiments: no foreknowledge in Experiment 1, partial foreknowledge (task transition only) in Experiment 2, and full foreknowledge in Experiment 3. For all experiments, the switch cost for Task 2 was additive with stimulus onset asynchrony, and the response-correspondence effect for Task 2 was numerically smaller in the switch condition than in the repeat condition. These outcomes suggest that reconfiguration for Task 2 takes place after the central processing of Task 1 and that the crosstalk correspondence effect is due to response activation by way of stimulus-response associations.

Role of switching-on and -off effects in the vacuum instability

NASA Astrophysics Data System (ADS)

Adorno, T. C.; Ferreira, R.; Gavrilov, S. P.; Gitman, D. M.

2018-04-01

We find exact differential mean numbers of fermions and bosons created from the vacuum due to a composite electric field of special configuration. This configuration imitates a finite switching-on and -off regime and consists of fields that switch on exponentially from the infinitely remote past, remains constant during a certain interval T and switch off exponentially to the infinitely remote future. We show that calculations in the slowly varying field approximation are completely predictable in the framework of a locally constant field approximation. Beyond the slowly varying field approximation, we study effects of fast switching on and off in a number of cases when the size of the dimensionless parameter eET is either close or exceeds the threshold value that determines the transition from a regime sensitive to on-off parameters to the slowly varying regime for which these effects are secondary.

Neutron and gamma irradiation effects on power semiconductor switches

NASA Technical Reports Server (NTRS)

Schwarze, G. E.; Frasca, A. J.

1990-01-01

The performance characteristics of high-power semiconductor switches subjected to high levels of neutron fluence and gamma dose must be known by the designer of the power conditioning, control and transmission subsystem of space nuclear power systems. Location and the allowable shielding mass budget will determine the level of radiation tolerance required by the switches to meet performance and reliability requirements. Neutron and gamma ray interactions with semiconductor materials and how these interactions affect the electrical and switching characteristics of solid state power switches is discussed. The experimental measurement system and radiation facilities are described. Experimental data showing the effects of neutron and gamma irradiation on the performance characteristics are given for power-type NPN Bipolar Junction Transistors (BJTs), and Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs). BJTs show a rapid decrease in gain, blocking voltage, and storage time for neutron irradiation, and MOSFETs show a rapid decrease in the gate threshold voltage for gamma irradiation.

Neutron and gamma irradiation effects on power semiconductor switches

NASA Technical Reports Server (NTRS)

Schwarze, G. E.; Frasca, A. J.

1990-01-01

The performance characteristics of high power semiconductor switches subjected to high levels of neutron fluence and gamma dose must be known by the designer of the power conditioning, control and transmission subsystem of space nuclear power systems. Location and the allowable shielding mass budget will determine the level of radiation tolerance required by the switches to meet performance and reliability requirements. Neutron and gamma ray interactions with semiconductor materials and how these interactions affect the electrical and switching characteristics of solid state power switches is discussed. The experimental measurement system and radiation facilities are described. Experimental data showing the effects of neutron and gamma irradiation on the performance characteristics are given for power-type NPN Bipolar Junction Transistors (BJTs), and Metal-Oxide-Semiconductor Field Effect Transistors (MOSFETs). BJTs show a rapid decrease in gain, blocking voltage, and storage time for neutron irradiation, and MOSFETs show a rapid decrease in the gate threshold voltage for gamma irradiation.

45° sign switching of effective exchange bias due to competing anisotropies in fully epitaxial Co3FeN/MnN bilayers.

PubMed

Hajiri, T; Yoshida, T; Filianina, M; Jaiswal, S; Borie, B; Asano, H; Zabel, H; Kläui, M

2017-12-05

We report an unusual angular-dependent exchange bias effect in ferromagnet/antiferromagnet bilayers, where both ferromagnet and antiferromagnet are epitaxially grown. Numerical model calculations predict an approximately 45° period for the sign switching of the exchange-bias field, depending on the ratio between magnetocrystalline anisotropy and exchange-coupling constant. The switching of the sign is indicative of a competition between a fourfold magnetocrystalline anisotropy of the ferromagnet and a unidirectional anisotropy field of the exchange coupling. This predicted unusual angular-dependent exchange bias and its magnetization switching process are confirmed by measurements on fully epitaxial Co 3 FeN/MnN bilayers by longitudinal and transverse magneto-optic Kerr effect magnetometry. These results provide a deeper understanding of the exchange coupling phenomena in fully epitaxial bilayers with tailored materials and open up a complex switching energy landscape engineering by anisotropies.

45° sign switching of effective exchange bias due to competing anisotropies in fully epitaxial Co3FeN/MnN bilayers

NASA Astrophysics Data System (ADS)

Hajiri, T.; Yoshida, T.; Filianina, M.; Jaiswal, S.; Borie, B.; Asano, H.; Zabel, H.; Kläui, M.

2018-01-01

We report an unusual angular-dependent exchange bias effect in ferromagnet/antiferromagnet bilayers, where both ferromagnet and antiferromagnet are epitaxially grown. Numerical model calculations predict an approximately 45° period for the sign switching of the exchange-bias field, depending on the ratio between magnetocrystalline anisotropy and exchange-coupling constant. The switching of the sign is indicative of a competition between a fourfold magnetocrystalline anisotropy of the ferromagnet and a unidirectional anisotropy field of the exchange coupling. This predicted unusual angular-dependent exchange bias and its magnetization switching process are confirmed by measurements on fully epitaxial Co3FeN/MnN bilayers by longitudinal and transverse magneto-optic Kerr effect magnetometry. These results provide a deeper understanding of the exchange coupling phenomena in fully epitaxial bilayers with tailored materials and open up a complex switching energy landscape engineering by anisotropies.

Event-Related Potential Responses to Task Switching Are Sensitive to Choice of Spatial Filter

PubMed Central

Wong, Aaron S. W.; Cooper, Patrick S.; Conley, Alexander C.; McKewen, Montana; Fulham, W. Ross; Michie, Patricia T.; Karayanidis, Frini

2018-01-01

Event-related potential (ERP) studies using the task-switching paradigm show that multiple ERP components are modulated by activation of proactive control processes involved in preparing to repeat or switch task and reactive control processes involved in implementation of the current or new task. Our understanding of the functional significance of these ERP components has been hampered by variability in their robustness, as well as their temporal and scalp distribution across studies. The aim of this study is to examine the effect of choice of reference electrode or spatial filter on the number, timing and scalp distribution of ERP elicited during task-switching. We compared four configurations, including the two most common (i.e., average mastoid reference and common average reference) and two novel ones that aim to reduce volume conduction (i.e., reference electrode standardization technique (REST) and surface Laplacian) on mixing cost and switch cost effects in cue-locked and target-locked ERP waveforms in 201 healthy participants. All four spatial filters showed the same well-characterized ERP components that are typically seen in task-switching paradigms: the cue-locked switch positivity and target-locked N2/P3 effect. However, both the number of ERP effects associated with mixing and switch cost, and their temporal and spatial resolution were greater with the surface Laplacian transformation which revealed rapid temporal adjustments that were not identifiable with other spatial filters. We conclude that the surface Laplacian transformation may be more suited to characterize EEG signatures of complex spatiotemporal networks involved in cognitive control. PMID:29568260

Long-acting family planning method switching among revisit clients of public health facilities in Dire Dawa, Ethiopia.

PubMed

Atnafe, Meselu; Assefa, Nega; Alemayehu, Tadesse

2016-01-01

"Contraceptive switching" from one method to another is a common phenomenon. Switching from a more effective long-acting method to a less effective method exposes women for unplanned pregnancy. The aim of this study was to assess the level and factors associated with long-acting family planning method switching to other methods. A facility-based cross-sectional study was conducted from January to March 2013 on 634 women attending public health facilities in Dire Dawa City Administration, Ethiopia. Participants of the study were revisit clients of family planning service and were interviewed as they appear in the clinics. Data were analyzed using crude and adjusted logistic regression, and results were reported using OR and corresponding 95 % CI. Long-acting family planning method switching among revisit clients was 40.4 %; switching from implant was 29.8 % and from IUCD, it was 10.6 %. The main reasons for methods switching were side effects of the methods such as bleeding, weight loss, and feeling of arm numbness. The tendency of switching was less among married women (AOR = 2.41, 95 % CI: 1.01, 5.74), women who had 2-4 and 5 and more children (AOR 3.00, 95 % CI: 1.59, 5.67) and (AOR 2.07, 95 % CI: 1.17, 3.66), respectively. It was also less among women who want to stop birth (AOR 5.11, 95 % CI: 1.15, 24.8), among those who mentioned health care providers as source of information for family planning (AOR 1.88, 95 % CI: 1.18, 3.01), and among women whose husbands were aware of their use of the methods (AOR 3.05, 95 % CI: 1.88, 4.94). Method switching from long-acting contraceptives to less effective methods is high. Method switching was significant among unmarried women, who had one child, plan to postpone fertility, and whose husbands were not aware of their wive's use of the method. In the provision of family planning service, the health care providers should give adequate information about each method and risks of method switching. Appropriate family planning Information Education and Communication (IEC) and Behavioral Change Communication (BCC) strategies should be emphasized.

Resistive switching and memory effects of AgI thin film

NASA Astrophysics Data System (ADS)

Liang, X. F.; Chen, Y.; Shi, L.; Lin, J.; Yin, J.; Liu, Z. G.

2007-08-01

A memory device has been fabricated using an AgI film sandwiched between a Pt film and an Ag film with the lateral size of the device scaled down to 300 nm. The AgI film was made by the iodination of the Ag film at room temperature and under ambient pressure. The switching between high- and low-resistance states can be realized by applying voltages of different polarities. The switching can be performed under the application of voltage pulses with a 100 Hz frequency for ~103 times. The switching times are in the order of microseconds and the retention time is about a week. The switching effects are explained as the electrochemical growth and dissolution of Ag in AgI.

Pressure-induced switching in ferroelectrics: Phase-field modeling, electrochemistry, flexoelectric effect, and bulk vacancy dynamics

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

Cao, Ye; Morozovska, Anna; Kalinin, Sergei V.

Pressure-induced polarization switching in ferroelectric thin films has emerged as a powerful method for domain patterning, allowing us to create predefined domain patterns on free surfaces and under thin conductive top electrodes. However, the mechanisms for pressure-induced polarization switching in ferroelectrics remain highly controversial, with flexoelectricity, polarization rotation and suppression, and bulk and surface electrochemical processes all being potentially relevant. Here we classify possible pressure-induced switching mechanisms, perform elementary estimates, and study in depth using phase-field modeling. Finally, we show that magnitudes of these effects are remarkably close and give rise to complex switching diagrams as a function of pressuremore » and film thickness with nontrivial topology or switchable and nonswitchable regions.« less

Solid state switch panel. [determination of optimum transducer type for required switches

NASA Technical Reports Server (NTRS)

Beenfeldt, E.

1973-01-01

An intensive study of various forms of transducers was conducted with application towards hermetically sealing the transducer and all electronics. The results of the study indicated that the Hall effect devices and a LED/phototransistor combination were the most practical for this type of application. Therefore, hardware was developed utilizing a magnet/Hall effect transducer for single action switches and LED/phototransistor transducers for rotary multiposition or potentiometer applications. All electronics could be housed in a hermetically sealed compartment. A number of switches were built and models were hermetically sealed to prove the feasibility of this type of fabrication. One of each type of switch was subjected to temperature cycling, vibration, and EMI tests. The results of these tests are presented.

Pressure-induced switching in ferroelectrics: Phase-field modeling, electrochemistry, flexoelectric effect, and bulk vacancy dynamics

DOE PAGES

Cao, Ye; Morozovska, Anna; Kalinin, Sergei V.

2017-11-01

Pressure-induced polarization switching in ferroelectric thin films has emerged as a powerful method for domain patterning, allowing us to create predefined domain patterns on free surfaces and under thin conductive top electrodes. However, the mechanisms for pressure-induced polarization switching in ferroelectrics remain highly controversial, with flexoelectricity, polarization rotation and suppression, and bulk and surface electrochemical processes all being potentially relevant. Here we classify possible pressure-induced switching mechanisms, perform elementary estimates, and study in depth using phase-field modeling. Finally, we show that magnitudes of these effects are remarkably close and give rise to complex switching diagrams as a function of pressuremore » and film thickness with nontrivial topology or switchable and nonswitchable regions.« less

Enhancing emotional experiences to dance through music: the role of valence and arousal in the cross-modal bias.

PubMed

Christensen, Julia F; Gaigg, Sebastian B; Gomila, Antoni; Oke, Peter; Calvo-Merino, Beatriz

2014-01-01

It is well established that emotional responses to stimuli presented to one perceptive modality (e.g., visual) are modulated by the concurrent presentation of affective information to another modality (e.g., auditory)-an effect known as the cross-modal bias. However, the affective mechanisms mediating this effect are still not fully understood. It remains unclear what role different dimensions of stimulus valence and arousal play in mediating the effect, and to what extent cross-modal influences impact not only our perception and conscious affective experiences, but also our psychophysiological emotional response. We addressed these issues by measuring participants' subjective emotion ratings and their Galvanic Skin Responses (GSR) in a cross-modal affect perception paradigm employing videos of ballet dance movements and instrumental classical music as the stimuli. We chose these stimuli to explore the cross-modal bias in a context of stimuli (ballet dance movements) that most participants would have relatively little prior experience with. Results showed (i) that the cross-modal bias was more pronounced for sad than for happy movements, whereas it was equivalent when contrasting high vs. low arousal movements; and (ii) that movement valence did not modulate participants' GSR, while movement arousal did, such that GSR was potentiated in the case of low arousal movements with sad music and when high arousal movements were paired with happy music. Results are discussed in the context of the affective dimension of neuroentrainment and with regards to implications for the art community.

Representations of temporal information in short-term memory: Are they modality-specific?

PubMed

Bratzke, Daniel; Quinn, Katrina R; Ulrich, Rolf; Bausenhart, Karin M

2016-10-01

Rattat and Picard (2012) reported that the coding of temporal information in short-term memory is modality-specific, that is, temporal information received via the visual (auditory) modality is stored as a visual (auditory) code. This conclusion was supported by modality-specific interference effects on visual and auditory duration discrimination, which were induced by secondary tasks (visual tracking or articulatory suppression), presented during a retention interval. The present study assessed the stability of these modality-specific interference effects. Our study did not replicate the selective interference pattern but rather indicated that articulatory suppression not only impairs short-term memory for auditory but also for visual durations. This result pattern supports a crossmodal or an abstract view of temporal encoding. Copyright © 2016 Elsevier B.V. All rights reserved.

An investigation of response and stimulus modality transfer effects after dual-task training in younger and older.

PubMed

Lussier, Maxime; Gagnon, Christine; Bherer, Louis

2012-01-01

It has been shown that dual-task training leads to significant improvement in dual-task performance in younger and older adults. However, the extent to which training benefits to untrained tasks requires further investigation. The present study assessed (a) whether dual-task training leads to cross-modality transfer in untrained tasks using new stimuli and/or motor responses modalities, (b) whether transfer effects are related to improved ability to prepare and maintain multiple task-set and/or enhanced response coordination, (c) whether there are age-related differences in transfer effects. Twenty-three younger and 23 older adults were randomly assigned to dual-task training or control conditions. All participants were assessed before and after training on three dual-task transfer conditions; (1) stimulus modality transfer (2) response modality transfer (3) stimulus and response modalities transfer task. Training group showed larger improvement than the control group in the three transfer dual-task conditions, which suggests that training leads to more than specific learning of stimuli/response associations. Attentional costs analyses showed that training led to improved dual-task cost, only in conditions that involved new stimuli or response modalities, but not both. Moreover, training did not lead to a reduced task-set cost in the transfer conditions, which suggests some limitations in transfer effects that can be expected. Overall, the present study supports the notion that cognitive plasticity for attentional control is preserved in late adulthood.

The art and science of switching antipsychotic medications, part 2.

PubMed

Weiden, Peter J; Miller, Alexander L; Lambert, Tim J; Buckley, Peter F

2007-01-01

In the presentation "Switching and Metabolic Syndrome," Weiden summarizes reasons to switch antipsychotics, highlighting weight gain and other metabolic adverse events as recent treatment targets. In "Texas Medication Algorithm Project (TMAP)," Miller reviews the TMAP study design, discusses results related to the algorithm versus treatment as usual, and concludes with the implications of the study. Lambert's presentation, "Dosing and Titration Strategies to Optimize Patient Outcome When Switching Antipsychotic Therapy," reviews the decision-making process when switching patients' medication, addresses dosing and titration strategies to effectively transition between medications, and examines other factors to consider when switching pharmacotherapy.

Acute effect of scapular proprioceptive neuromuscular facilitation (PNF) techniques and classic exercises in adhesive capsulitis: a randomized controlled trial

PubMed Central

Balcı, Nilay Comuk; Yuruk, Zeliha Ozlem; Zeybek, Aslican; Gulsen, Mustafa; Tekindal, Mustafa Agah

2016-01-01

[Purpose] The aim of our study was to compare the initial effects of scapular proprioceptive neuromuscular facilitation techniques and classic exercise interventions with physiotherapy modalities on pain, scapular dyskinesis, range of motion, and function in adhesive capsulitis. [Subjects and Methods] Fifty-three subjects were allocated to 3 groups: scapular proprioceptive neuromuscular facilitation exercies and physiotherapy modalities, classic exercise and physiotherapy modalities, and only physiotherapy modalities. The intervention was applied in a single session. The Visual Analog Scale, Lateral Scapular Slide Test, range of motion and Simple Shoulder Test were evaluated before and just after the one-hour intervention in the same session (all in one session). [Results] All of the groups showed significant differences in shoulder flexion and abduction range of motion and Simple Shoulder Test scores. There were statistically significant differences in Visual Analog Scale scores in the proprioceptive neuromuscular facilitation and control groups, and no treatment method had significant effect on the Lateral Scapular Slide Test results. There were no statistically significant differences between the groups before and after the intervention. [Conclusion] Proprioceptive neuromuscular facilitation, classic exercise, and physiotherapy modalities had immediate effects on adhesive capsulitis in our study. However, there was no additional benefit of exercises in one session over physiotherapy modalities. Also, an effective treatment regimen for shoulder rehabilitation of adhesive capsulitis patients should include scapular exercises. PMID:27190456

Cross-modal discrepancies in coarticulation and the integration of speech information: the McGurk effect with mismatched vowels.

PubMed

Green, K P; Gerdeman, A

1995-12-01

Two experiments examined the impact of a discrepancy in vowel quality between the auditory and visual modalities on the perception of a syllable-initial consonant. One experiment examined the effect of such a discrepancy on the McGurk effect by cross-dubbing auditory /bi/ tokens onto visual /ga/ articulations (and vice versa). A discrepancy in vowel category significantly reduced the magnitude of the McGurk effect and changed the pattern of responses. A 2nd experiment investigated the effect of such a discrepancy on the speeded classification of the initial consonant. Mean reaction times to classify the tokens increased when the vowel information was discrepant between the 2 modalities but not when the vowel information was consistent. These experiments indicate that the perceptual system is sensitive to cross-modal discrepancies in the coarticulatory information between a consonant and its following vowel during phonetic perception.

Interactions Between Modality of Working Memory Load and Perceptual Load in Distractor Processing.

PubMed

Koshino, Hideya; Olid, Pilar

2015-01-01

The present study investigated interactions between working memory load and perceptual load. The load theory (Lavie, Hirst, de Fockert, & Viding, 2004 ) claims that perceptual load decreases distractor interference, whereas working memory load increases interference. However, recent studies showed that effects of working memory might depend on the relationship between modalities of working memory and task stimuli. Here, we examined whether the relationship between working memory load and perceptual load would remain the same across modalities. The results of Experiment 1 showed that verbal working memory load did not affect a compatibility effect for low perceptual load, whereas it increased the compatibility effect for high perceptual load. In Experiment 2, the compatibility effect remained the same regardless of visual working memory load. These results suggest that the effects of working memory load and perceptual load depend on the relationship between the modalities of working memory and stimuli.

Characterization and snubbing of a bidirectional MCT in a resonant ac link converter

NASA Technical Reports Server (NTRS)

Lee, Tony; Elbuluk, Malik E.; Zinger, Donald S.

1993-01-01

The MOS-Controlled Thyristor (MCT) is emerging as a powerful switch that combines the better characteristics of existing power devices. A study of switching stresses on an MCT switch under zero voltage resonant switching is presented. The MCT is used as a bidirectional switch in an ac/ac pulse density modulated inverter for induction motor drive. Current and voltage spikes are observed and analyzed with variations in the timing of the switching. Different snubber circuit configurations are under investigation to minimize the effect of these transients. The results will be extended to study and test the MCT switching in a medium power (5 hp) induction motor drive.

Adjusting for treatment switching in randomised controlled trials - A simulation study and a simplified two-stage method.

PubMed

Latimer, Nicholas R; Abrams, K R; Lambert, P C; Crowther, M J; Wailoo, A J; Morden, J P; Akehurst, R L; Campbell, M J

2017-04-01

Estimates of the overall survival benefit of new cancer treatments are often confounded by treatment switching in randomised controlled trials (RCTs) - whereby patients randomised to the control group are permitted to switch onto the experimental treatment upon disease progression. In health technology assessment, estimates of the unconfounded overall survival benefit associated with the new treatment are needed. Several switching adjustment methods have been advocated in the literature, some of which have been used in health technology assessment. However, it is unclear which methods are likely to produce least bias in realistic RCT-based scenarios. We simulated RCTs in which switching, associated with patient prognosis, was permitted. Treatment effect size and time dependency, switching proportions and disease severity were varied across scenarios. We assessed the performance of alternative adjustment methods based upon bias, coverage and mean squared error, related to the estimation of true restricted mean survival in the absence of switching in the control group. We found that when the treatment effect was not time-dependent, rank preserving structural failure time models (RPSFTM) and iterative parameter estimation methods produced low levels of bias. However, in the presence of a time-dependent treatment effect, these methods produced higher levels of bias, similar to those produced by an inverse probability of censoring weights method. The inverse probability of censoring weights and structural nested models produced high levels of bias when switching proportions exceeded 85%. A simplified two-stage Weibull method produced low bias across all scenarios and provided the treatment switching mechanism is suitable, represents an appropriate adjustment method.

Roles of context in acquisition of human instrumental learning: Implications for the understanding of the mechanisms underlying context-switch effects.

PubMed

Gámez, A Matías; León, Samuel P; Rosas, Juan M

2017-09-01

Four experiments in human instrumental learning explored the associations involving the context that develop after three trials of training on simple discriminations. Experiments 1 and 4 found a deleterious effect of switching the learning context that cannot be explained by the context-outcome binary associations commonly used to explain context-switch effects after short training in human predictive learning and in animal Pavlovian conditioning. Evidence for context-outcome (Experiment 2), context-discriminative stimulus (Experiment 3), and context-instrumental response (Experiment 4) binary associations was found within the same training paradigm, suggesting that contexts became associated with all the elements of the situation, regardless of whether those associations played a role in a specific context-switch effect detected on performance.

An all-optical switch based on a surface plasmon polariton resonator

NASA Astrophysics Data System (ADS)

Pan, Zijuan; Lang, Peilin; Duan, Gaoyan

2018-04-01

All-optical switch is one of the key parts of optical circuit. We employ a temperature-sensitive resonator to form an optical switch. The resonator deforms under the applied light and adjusts the transmittance of the structure. To our knowledge, this is the first design of an all-optical surface plasmon polariton (SPP) switch based on the heat deformation effect.

High-voltage, high-current, solid-state closing switch

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

Focia, Ronald Jeffrey

2017-08-22

A high-voltage, high-current, solid-state closing switch uses a field-effect transistor (e.g., a MOSFET) to trigger a high-voltage stack of thyristors. The switch can have a high hold-off voltage, high current carrying capacity, and high time-rate-of-change of current, di/dt. The fast closing switch can be used in pulsed power applications.

Functional brain and age-related changes associated with congruency in task switching

PubMed Central

Eich, Teal S.; Parker, David; Liu, Dan; Oh, Hwamee; Razlighi, Qolamreza; Gazes, Yunglin; Habeck, Christian; Stern, Yaakov

2016-01-01

Alternating between completing two simple tasks, as opposed to completing only one task, has been shown to produce costs to performance and changes to neural patterns of activity, effects which are augmented in old age. Cognitive conflict may arise from factors other than switching tasks, however. Sensorimotor congruency (whether stimulus-response mappings are the same or different for the two tasks) has been shown to behaviorally moderate switch costs in older, but not younger adults. In the current study, we used fMRI to investigate the neurobiological mechanisms of response-conflict congruency effects within a task switching paradigm in older (N=75) and younger (N=62) adults. Behaviorally, incongruency moderated age-related differences in switch costs. Neurally, switch costs were associated with greater activation in the dorsal attention network for older relative to younger adults. We also found that older adults recruited an additional set of brain areas in the ventral attention network to a greater extent than did younger adults to resolve congruency-related response-conflict. These results suggest both a network and an age-based dissociation between congruency and switch costs in task switching. PMID:27520472

LMI-based adaptive reliable H∞ static output feedback control against switched actuator failures

NASA Astrophysics Data System (ADS)

An, Liwei; Zhai, Ding; Dong, Jiuxiang; Zhang, Qingling

2017-08-01

This paper investigates the H∞ static output feedback (SOF) control problem for switched linear system under arbitrary switching, where the actuator failure models are considered to depend on switching signal. An active reliable control scheme is developed by combination of linear matrix inequality (LMI) method and adaptive mechanism. First, by exploiting variable substitution and Finsler's lemma, new LMI conditions are given for designing the SOF controller. Compared to the existing results, the proposed design conditions are more relaxed and can be applied to a wider class of no-fault linear systems. Then a novel adaptive mechanism is established, where the inverses of switched failure scaling factors are estimated online to accommodate the effects of actuator failure on systems. Two main difficulties arise: first is how to design the switched adaptive laws to prevent the missing of estimating information due to switching; second is how to construct a common Lyapunov function based on a switched estimate error term. It is shown that the new method can give less conservative results than that for the traditional control design with fixed gain matrices. Finally, simulation results on the HiMAT aircraft are given to show the effectiveness of the proposed approaches.

Analysis of the costs of dialysis and the effects of an incentive mechanism for low-cost dialysis modalities.

PubMed

Cleemput, Irina; De Laet, Chris

2013-05-01

Treatment costs of end-stage renal disease with dialysis are high and vary between dialysis modalities. Public healthcare payers aim at stimulating the use of less expensive dialysis modalities, with maintenance of healthcare quality. This study examines the effects of Belgian financial incentive mechanisms for the use of low-cost dialysis treatments. First, the costs of different dialysis modalities were calculated from the hospital's perspective. Data were obtained through a hospital survey. The balance between costs and revenues was simulated for an average Belgian dialysis programme. Incremental profits were calculated in function of the proportion of patients on alternative dialysis modalities. Hospital haemodialysis is the most expensive modality per patient year, followed by peritoneal dialysis and finally satellite haemodialysis. Under current reimbursement rules mean profits of a dialysis programme are maximal if about 28% of patients are treated with a low-cost dialysis modality. This is only slightly lower than the observed percentage in Belgian dialysis centres in the same period. In Belgium, the financial incentives for the use of low-cost dialysis modalities only had a modest impact due to the continuing profits that could be generated by high-cost dialysis. Profit neutrality is crucial for the success of any financial incentive mechanism for low-cost dialysis modalities. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Multi-gap high impedance plasma opening switch

DOEpatents

Mason, Rodney J.

1996-01-01

A high impedance plasma opening switch having an anode and a cathode and at least one additional electrode placed between the anode and cathode. The presence of the additional electrodes leads to the creation of additional plasma gaps which are in series, increasing the net impedance of the switch. An equivalent effect can be obtained by using two or more conventional plasma switches with their plasma gaps wired in series. Higher impedance switches can provide high current and voltage to higher impedance loads such as plasma radiation sources.

Afternoon nap and bright light exposure improve cognitive flexibility post lunch.

PubMed

Slama, Hichem; Deliens, Gaétane; Schmitz, Rémy; Peigneux, Philippe; Leproult, Rachel

2015-01-01

Beneficial effects of napping or bright light exposure on cognitive performance have been reported in participants exposed to sleep loss. Nonetheless, few studies investigated the effect of these potential countermeasures against the temporary drop in performance observed in mid-afternoon, and even less so on cognitive flexibility, a crucial component of executive functions. This study investigated the impact of either an afternoon nap or bright light exposure on post-prandial alterations in task switching performance in well-rested participants. Twenty-five healthy adults participated in two randomized experimental conditions, either wake versus nap (n=15), or bright light versus placebo (n=10). Participants were tested on a switching task three times (morning, post-lunch and late afternoon sessions). The interventions occurred prior to the post-lunch session. In the nap/wake condition, participants either stayed awake watching a 30-minute documentary or had the opportunity to take a nap for 30 minutes. In the bright light/placebo condition, participants watched a documentary under either bright blue light or dim orange light (placebo) for 30 minutes. The switch cost estimates cognitive flexibility and measures task-switching efficiency. Increased switch cost scores indicate higher difficulties to switch between tasks. In both control conditions (wake or placebo), accuracy switch-cost score increased post lunch. Both interventions (nap or bright light) elicited a decrease in accuracy switch-cost score post lunch, which was associated with diminished fatigue and decreased variability in vigilance. Additionally, there was a trend for a post-lunch benefit of bright light with a decreased latency switch-cost score. In the nap group, improvements in accuracy switch-cost score were associated with more NREM sleep stage N1. Thus, exposure to bright light during the post-lunch dip, a countermeasure easily applicable in daily life, results in similar beneficial effects as a short nap on performance in the cognitive flexibility domain with possible additional benefits on latency switch-cost scores.

Afternoon Nap and Bright Light Exposure Improve Cognitive Flexibility Post Lunch

PubMed Central

Schmitz, Rémy; Peigneux, Philippe; Leproult, Rachel

2015-01-01

Beneficial effects of napping or bright light exposure on cognitive performance have been reported in participants exposed to sleep loss. Nonetheless, few studies investigated the effect of these potential countermeasures against the temporary drop in performance observed in mid-afternoon, and even less so on cognitive flexibility, a crucial component of executive functions. This study investigated the impact of either an afternoon nap or bright light exposure on post-prandial alterations in task switching performance in well-rested participants. Twenty-five healthy adults participated in two randomized experimental conditions, either wake versus nap (n=15), or bright light versus placebo (n=10). Participants were tested on a switching task three times (morning, post-lunch and late afternoon sessions). The interventions occurred prior to the post-lunch session. In the nap/wake condition, participants either stayed awake watching a 30-minute documentary or had the opportunity to take a nap for 30 minutes. In the bright light/placebo condition, participants watched a documentary under either bright blue light or dim orange light (placebo) for 30 minutes. The switch cost estimates cognitive flexibility and measures task-switching efficiency. Increased switch cost scores indicate higher difficulties to switch between tasks. In both control conditions (wake or placebo), accuracy switch-cost score increased post lunch. Both interventions (nap or bright light) elicited a decrease in accuracy switch-cost score post lunch, which was associated with diminished fatigue and decreased variability in vigilance. Additionally, there was a trend for a post-lunch benefit of bright light with a decreased latency switch-cost score. In the nap group, improvements in accuracy switch-cost score were associated with more NREM sleep stage N1. Thus, exposure to bright light during the post-lunch dip, a countermeasure easily applicable in daily life, results in similar beneficial effects as a short nap on performance in the cognitive flexibility domain with possible additional benefits on latency switch-cost scores. PMID:26016658

Ultrafast Coherent Dynamics of a Photonic Crystal All-Optical Switch.

PubMed

Colman, Pierre; Lunnemann, Per; Yu, Yi; Mørk, Jesper

2016-12-02

We present pump-probe measurements of an all-optical photonic crystal switch based on a nanocavity, resolving fast coherent temporal dynamics. The measurements demonstrate the importance of coherent effects typically neglected when considering nanocavity dynamics. In particular, we report the observation of an idler pulse and more than 10 dB parametric gain. The measurements are in good agreement with a theoretical model that ascribes the observation to oscillations of the free-carrier population in the nanocavity. The effect opens perspectives for the realization of new all-optical photonic crystal switches with unprecedented switching contrast.

Predictors of treatment with dialysis modalities in observational studies for comparative effectiveness research.

PubMed

Kuttykrishnan, Sooraj; Kalantar-Zadeh, Kamyar; Arah, Onyebuchi A; Cheung, Alfred K; Brunelli, Steve; Heagerty, Patrick J; Katz, Ronit; Molnar, Miklos Z; Nissenson, Allen; Ravel, Vanessa; Streja, Elani; Himmelfarb, Jonathan; Mehrotra, Rajnish

2015-07-01

The Institute of Medicine has identified the comparative effectiveness of renal replacement therapies as a kidney-related topic among the top 100 national priorities. Given the importance of ensuring internal and external validity, the goal of this study was to identify potential sources of bias in observational studies that compare outcomes with different dialysis modalities. This observational cohort study used data from the electronic medical records of all patients that started maintenance dialysis in the calendar years 2007-2011 and underwent treatment for at least 60 days in any of the 2217 facilities operated by DaVita Inc. Each patient was assigned one of six dialysis modalities for each 91-day period from the date of first dialysis (thrice weekly in-center hemodialysis (HD), peritoneal dialysis (PD), less-frequent HD, home HD, frequent HD and nocturnal in-center HD). Of the 162 644 patients, 18% underwent treatment with a modality other than HD for at least one 91-day period. Except for PD, patients started treatment with alternative modalities after variable lengths of treatment with HD; the time until a change in modality was shortest for less-frequent HD (median time = 6 months) and longest for frequent HD (median time = 15 months). Between 30 and 78% of patients transferred to another dialysis facility prior to change in modality. Finally, there were significant differences in baseline and time-varying clinical characteristics associated with dialysis modality. This analysis identified numerous potential sources of bias in studies of the comparative effectiveness of dialysis modalities. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Systematic Review of the Effectiveness of Physical Therapy Modalities in Women With Provoked Vestibulodynia.

PubMed

Morin, Mélanie; Carroll, Marie-Soleil; Bergeron, Sophie

2017-07-01

Pelvic floor muscle physical therapy is recommended in clinical guidelines for women with provoked vestibulodynia (PVD). Including isolated or combined treatment modalities, physical therapy is viewed as an effective first-line intervention, yet no systematic review concerning the effectiveness of physical therapy has been conducted. To systematically appraise the current literature on the effectiveness of physical therapy modalities for decreasing pain during intercourse and improving sexual function in women with PVD. A systematic literature search using PubMed, Scopus, CINHAL, and PEDro was conducted until October 2016. Moreover, a manual search from reference lists of included articles was performed. Ongoing trials also were reviewed using clinicaltrial.gov and ISRCTNregistry. Randomized controlled trials, prospective and retrospective cohorts, and case reports evaluating the effect of isolated or combined physical therapy modalities in women with PVD were included in the review. Main outcome measures were pain during intercourse, sexual function, and patient's perceived improvement. The literature search resulted in 43 eligible studies including 7 randomized controlled trials, 20 prospective studies, 5 retrospective studies, 6 case reports, and 6 study protocols. Most studies had a high risk of bias mainly associated with the lack of a comparison group. Another common bias was related to insufficient sample size, non-validated outcomes, non-standardized intervention, and use of other ongoing treatment. The vast majority of studies showed that physical therapy modalities such as biofeedback, dilators, electrical stimulation, education, multimodal physical therapy, and multidisciplinary approaches were effective for decreasing pain during intercourse and improving sexual function. The positive findings for the effectiveness of physical therapy modalities in women with PVD should be investigated further in robust and well-designed randomized controlled trials. Morin M, Carroll M-S, Bergeron S. Systematic Review of the Effectiveness of Physical Therapy Modalities in Women With Provoked Vestibulodynia. Sex Med Rev 2017;5:295-322. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

Adaptation to faces and voices: unimodal, cross-modal, and sex-specific effects.

PubMed

Little, Anthony C; Feinberg, David R; Debruine, Lisa M; Jones, Benedict C

2013-11-01

Exposure, or adaptation, to faces or voices biases perceptions of subsequent stimuli, for example, causing faces to appear more normal than they would be otherwise if they are similar to the previously presented stimuli. Studies also suggest that there may be cross-modal adaptation between sound and vision, although the evidence is inconsistent. We examined adaptation effects within and across voices and faces and also tested whether adaptation crosses between male and female stimuli. We exposed participants to sex-typical or sex-atypical stimuli and measured the perceived normality of subsequent stimuli. Exposure to female faces or voices altered perceptions of subsequent female stimuli, and these adaptation effects crossed modality; exposure to voices influenced judgments of faces, and vice versa. We also found that exposure to female stimuli did not influence perception of subsequent male stimuli. Our data demonstrate that recent experience of faces and voices changes subsequent perception and that mental representations of faces and voices may not be modality dependent. Both unimodal and cross-modal adaptation effects appear to be relatively sex-specific.

A single-stage optical load-balanced switch for data centers.

PubMed

Huang, Qirui; Yeo, Yong-Kee; Zhou, Luying

2012-10-22

Load balancing is an attractive technique to achieve maximum throughput and optimal resource utilization in large-scale switching systems. However current electronic load-balanced switches suffer from severe problems in implementation cost, power consumption and scaling. To overcome these problems, in this paper we propose a single-stage optical load-balanced switch architecture based on an arrayed waveguide grating router (AWGR) in conjunction with fast tunable lasers. By reuse of the fast tunable lasers, the switch achieves both functions of load balancing and switching through the AWGR. With this architecture, proof-of-concept experiments have been conducted to investigate the feasibility of the optical load-balanced switch and to examine its physical performance. Compared to three-stage load-balanced switches, the reported switch needs only half of optical devices such as tunable lasers and AWGRs, which can provide a cost-effective solution for future data centers.

Results from EuCliD (European Clinical Dialysis Database): impact of shifting treatment modality.

PubMed

Merello Godino, J I; Rentero, R; Orlandini, G; Marcelli, D; Ronco, C

2002-11-01

The use of biocompatible high-flux membranes is more efficient than low-flux membranes in controlling a number of hemodialysis-related diseases. The aim of this cooperative study was to evaluate the 6-month effect of a switch from low- to high-flux dialysers on patients treated in 39 Spanish dialysis centres. The clinical data used in this analysis were prospectively collected by the EuCliD database, developed to monitor the quality of treatment delivered in a large network of European Dialysis Centres. Inclusion criteria for the study were the condition of end-stage renal disease (ESRD) on chronic hemodialysis and low-flux dialysis for at least six months before the switch to high-flux dialysis. Of 1,543 patients enrolled in the study between 2000 and 2001, 1,046 patients were considered for the analysis. 497 patients were excluded because they did not complete the follow-up. Outcome measures were the reduction of pre-dialysis beta-2 microglobulin, the improvement of anemia or reduction in rHu-EPO dose required to maintain best correction of anemia, reduction of inflammatory parameters (CRP), improvement in lipid profile (Total and HDL cholesterol, tryglycerides), maintenance of nutritional status. Albumin and "dry" (post-hemodialysis) body weight were both evaluated as nutritional indexes. During the six months of high-flux hemodialysis, there was a significant increase in hemoglobin (from 11.55 +/- 1.41 to 11.88 +/- 1.43 g/L; p < 0.001). Considering the temporarily untreated patients on a 0 U/week dose, erythropoietin remained stable (from 5,670 +/- 4,199 to 5,657 +/- 4,411 U/week). During the second part of the follow-up, the lipid profile significantly improved (Fig. 3). Total cholesterol and triglycerides decreased significantly (p < 0.001), while HDL cholesterol increased (p = 0.006). Calculated levels of LDL cholesterol also significantly decreased (p = 0.001). Dry body weight remained stable (64.7 +/- 11.9 vs. 64.7 +/- 12.0 kg) as well as in albumin levels (3.93 +/- 0.43 vs. 3.94 +/- 0.43 g/dL) between the two modalities of treatment. The level of beta2-microglobulin significantly decreased during high-flux dialysis (33.5 +/- 14.4 vs. 26.3 +/- 8.6 mg/dL, p < 0.001). All above mentioned results may have as a common denominator an improved blood purification from uremic toxins and a reduced level of chronic sub-clinical inflammation. All together, these results seem to confirm the superiority of high-flux dialysis in terms of clinical and physiological outcomes.

Investigating the Effect of Voltage-Switching on Low-Energy Task Scheduling in Hard Real-Time Systems

DTIC Science & Technology

2005-01-01

We investigate the effect of voltage-switching on task execution times and energy consumption for dual-speed hard real - time systems , and present a...scheduling algorithm and apply it to two real-life task sets. Our results show that energy can be conserved in embedded real - time systems using energy...aware task scheduling. We also show that switching times have a significant effect on the energy consumed in hard real - time systems .

Leverage effect, economic policy uncertainty and realized volatility with regime switching

NASA Astrophysics Data System (ADS)

Duan, Yinying; Chen, Wang; Zeng, Qing; Liu, Zhicao

2018-03-01

In this study, we first investigate the impacts of leverage effect and economic policy uncertainty (EPU) on future volatility in the framework of regime switching. Out-of-sample results show that the HAR-RV including the leverage effect and economic policy uncertainty with regimes can achieve higher forecast accuracy than RV-type and GARCH-class models. Our robustness results further imply that these factors in the framework of regime switching can substantially improve the HAR-RV's forecast performance.

[Results of Re-switch from Intravitreal Aflibercept to Ranibizumab in Patients with Exudative Age-related Macular Degeneration].

PubMed

Waibel, Sören; Matthé, Egbert; Sandner, Dirk

2018-05-01

The purpose of this study was to investigate the effectiveness of re-switch from intravitreal aflibercept to ranibizumab in patients with exudative age-related macular degeneration. This retrospective case series included 17 eyes of 17 patients who had previously switched from ranibizumab to aflibercept and finally back to ranibizumab. Main outcomes were change of visual acuity (VA) and assessment of central macular thickness (CMT). Secondary outcomes included predictive factors which had a beneficial effect as VA and CMT before re-switch, number of previous injections and gender. The mean VA was 0.64 ± 0.36 logMAR before the switch, and 0.87 ± 0.40 logMAR before the re-switch, and gained with a slight but not significantly improvement up to 0.85 ± 0.58 logMAR after the re-switch (p = 0.896). The average CMT before the switch was 448.6 µm ± 181.5. This decreased to 343.8 µm ± 161.3 after the switch (p = 0.614) to 299.1 µm ± 155.8 at switchback (p = 0.133). Overall, 8 patients (47%) had an improvement of vision, whereas in 5 patients (30%) VA deteriorated. Further analysis of predictive factors revealed a mean improvement of VA in male patients after re-switch, while female patients lost VA, with statistical significance between after the switch and after the re-switch to the benefit of male patients (p = 0.016). A re-switch from aflibercept to ranibizumab may enable improvement in morphological parameters and stabilization of VA in patients with exudative age-related macular degeneration who achieved no more benefit from the initial switch. Georg Thieme Verlag KG Stuttgart · New York.

Consequences of non-medical switch among patients with type 2 diabetes.

PubMed

Flores, Natalia M; Patel, Charmi A; Bookhart, Brahim K; Bacchus, Shaffeeulah

2018-04-27

This study aimed to describe real-world experiences following a non-medical switch among adults with type 2 diabetes mellitus (T2DM) in the United States. For this cross-sectional study, patients with T2DM (N = 451) provided data on demographics, and how a non-medical switch of their anti-hyperglycemic agent (AHA) affected their general health, HbA1c levels and medication management, via an Internet-based survey. Patients self-reported their level of satisfaction with the original medication and emotional reactions to the non-medical switch. Patients who recently experienced a non-medical switch of their AHA(s) (n = 379) were asked about the consequences of switching and their satisfaction with the switch (vs. the original) medication. Patients most frequently reported feeling very/extremely frustrated, surprised, upset and angry in reaction to a non-medical switch. Patients were somewhat satisfied with their original medication. Between 20% and 30% of patients reported the non-medical switch had a moderate/major effect on their general health, diabetes, mental well-being and control over their health. The blood glucose levels of recent switchers were somewhat/much worse (20.7%) and medication management was somewhat/much worse (12.9%) on the switch (vs. the original) medication. Some recent switchers reported old symptoms returning (7.7%) and experiencing new side-effects (14.2%). Approximately one in five patients reported a moderate/major negative impact on their blood glucose level, diabetes, mental well-being, general health and control over their health following a non-medical switch. Findings suggest that a non-medical switch may have unintended negative health consequences and results in considerable burden across multiple domains for a sizeable minority of patients with T2DM.

Cognitive Load Theory and the Effects of Transient Information on the Modality Effect

ERIC Educational Resources Information Center

Leahy, Wayne; Sweller, John

2016-01-01

Based on cognitive load theory and the "transient information effect," this paper investigated the "modality effect" while interpreting a contour map. The length and complexity of auditory and visual text instructions were manipulated. Experiment 1 indicated that longer audio text information within a presentation was inferior…

Matching Teaching and Learning Styles.

ERIC Educational Resources Information Center

Caudill, Gil

1998-01-01

Outlines three basic learning modalities--auditory, visual, and tactile--and notes that technology can help incorporate multiple modalities within each lesson, to meet the needs of most students. Discusses the importance in multiple modality teaching of effectively assessing students. Presents visual, auditory and tactile activity suggestions.…

Auditory, visual and auditory-visual memory and sequencing performance in typically developing children.

PubMed

Pillai, Roshni; Yathiraj, Asha

2017-09-01

The study evaluated whether there exists a difference/relation in the way four different memory skills (memory score, sequencing score, memory span, & sequencing span) are processed through the auditory modality, visual modality and combined modalities. Four memory skills were evaluated on 30 typically developing children aged 7 years and 8 years across three modality conditions (auditory, visual, & auditory-visual). Analogous auditory and visual stimuli were presented to evaluate the three modality conditions across the two age groups. The children obtained significantly higher memory scores through the auditory modality compared to the visual modality. Likewise, their memory scores were significantly higher through the auditory-visual modality condition than through the visual modality. However, no effect of modality was observed on the sequencing scores as well as for the memory and the sequencing span. A good agreement was seen between the different modality conditions that were studied (auditory, visual, & auditory-visual) for the different memory skills measures (memory scores, sequencing scores, memory span, & sequencing span). A relatively lower agreement was noted only between the auditory and visual modalities as well as between the visual and auditory-visual modality conditions for the memory scores, measured using Bland-Altman plots. The study highlights the efficacy of using analogous stimuli to assess the auditory, visual as well as combined modalities. The study supports the view that the performance of children on different memory skills was better through the auditory modality compared to the visual modality. Copyright © 2017 Elsevier B.V. All rights reserved.

Life's a switch. Experiences in NSF undergraduate design projects.

PubMed

Popp, Stephanie A; Barnes, Jennifer R; Barrett, Steven F; Laurin, Kathy M

2003-01-01

During the summer of 2002 Stephanie Popp and Jennifer Barnes developed a manual, "Life's a Switch," through a project funded by the National Science Foundation. This manual teaches people how to build their own cost effective assistive switches. Assistive switches are a form of assistive technology which includes any device that enhances a person's quality of life by improving the individual's mobility, ability to perform daily activities, enhancing communication, or allowing participation in education, vocational activities and recreation. One main goal of assistive technology is to provide opportunities for children with disabilities to explore, play, learn, and communicate with others. Switches are essential tools used to provide these opportunities. When a child with developmental disabilities understands the connection between the activation of a switch and the resulting action it triggers, the knowledge of cause and effect is gained. Therefore, the basis for all future learning is established [1]. One of the current problems facing assistive switch users is the cost of available items. This project provides more affordable solutions for switch users by teaching the families and educators of switch users how to make their own switches and adaptors in the "Life's a Switch" manual. For example, some assistive technology vendors sell large button switches from $25.00 to $45.00, tread switches for $40.00, and pillow switches for $35.00 [2]. Amazingly, all parts and tools used to make these assistive switches can be bought and made into personally designed assistive devices averaging a cost of around $10.00 [3]. A workshop to teach this manual was also developed. This workshop will spread awareness of the more affordable options this project sets forth. In September of 2002, the first workshop was held in a laboratory classroom at the University of Wyoming's College of Engineering. Each attendant was provided with a kit that included all essential tools and components needed to make an assistive switch. Workshops scheduled into 2003 will provide educational opportunities for participants as well as opportunities for improvement of the manual.

The role of satisfaction and switching costs in Medicare Part D choices.

PubMed

Han, Jayoung; Ko, Dong Woo; Urmie, Julie M

2014-01-01

Most U.S. states had over 50 Medicare Prescription Drug Plans (PDPs) in 2007. Medicare beneficiaries are expected to switch Part D plans based on their health and financial needs; however, the switching rate has been low. Such consumer inertia potentially has negative effects on both beneficiaries and the insurance market, resulting in a critical need to investigate its cause. To 1) describe how Medicare beneficiaries who were satisfied with their current Part D plan differed from those who were not satisfied; 2) examine the effect of switching costs on consideration of switching among Medicare beneficiaries who were dissatisfied with their current Part D plan. Data from the 2007 Prescription Drug Study supplement to the Health and Retirement Study (HRS) survey were used in this study. The satisfied and dissatisfied groups were compared in terms of cost variables, switching costs, and perception of Part D complexity. Structural equation modeling was used to examine relationships among switching costs, Part D complexity, cost variables, and consideration of switching for beneficiaries who were dissatisfied with their current Part D coverage. Out of 467 participants, a total of 255 (54.6%) were satisfied with their current Part D plan. The satisfied group paid lower out-of-pocket costs ($50.63 vs. $114.60) and premiums ($30.88 vs. $40.77) than the dissatisfied group. They also had lower switching costs. Only 11.3% of the dissatisfied beneficiaries switched plans. Among respondents who were dissatisfied with their current plan, those who perceived Part D as complex had high switching costs and were less likely to consider switching plans. Out-of-pocket cost did not have a statistically significant association with consideration of switching. Medicare beneficiaries who were satisfied with their current Part D plans had lower out-of-pocket costs and premiums as well as higher switching costs. Among beneficiaries who were dissatisfied with their current Part D plan, those who had higher switching costs were less likely to consider switching Part D plans. Copyright © 2014 Elsevier Inc. All rights reserved.

Interplay between ferroelectric and resistive switching in doped crystalline HfO2

NASA Astrophysics Data System (ADS)

Max, Benjamin; Pešić, Milan; Slesazeck, Stefan; Mikolajick, Thomas

2018-04-01

Hafnium oxide is widely used for resistive switching devices, and recently it has been discovered that ferroelectricity can be established in (un-)doped hafnium oxide as well. Previous studies showed that both switching mechanisms are influenced by oxygen vacancies. For resistive switching, typically amorphous oxide layers with an asymmetric electrode configuration are used to create a gradient of oxygen vacancies. On the other hand, ferroelectric switching is performed by having symmetric electrodes and requires crystalline structures. The coexistence of both effects has recently been demonstrated. In this work, a detailed analysis of the reversible interplay of both switching mechanisms within a single capacitor cell is investigated. First, ferroelectric switching cycles were applied in order to drive the sample into the fatigued stage characterized by increased concentration of oxygen vacancies in the oxide layer. Afterwards, a forming step that is typical for the resistive switching devices was utilized to achieve a soft breakdown. In the next step, twofold alternation between the high and low resistance state is applied to demonstrate the resistive switching behavior of the device. Having the sample in the high resistance state with a ruptured filament, ferroelectric switching behavior is again shown within the same stack. Interestingly, the same endurance as before was observed without a hard breakdown of the device. Therefore, an effective sequence of ferroelectric—resistive—ferroelectric switching is realized. Additionally, the dependence of the forming, set, and reset voltage on the ferroelectric cycling stage (pristine, woken-up and fatigued) is analyzed giving insight into the physical device operation.

Letter Position Coding Across Modalities: The Case of Braille Readers

PubMed Central

Perea, Manuel; García-Chamorro, Cristina; Martín-Suesta, Miguel; Gómez, Pablo

2012-01-01

Background The question of how the brain encodes letter position in written words has attracted increasing attention in recent years. A number of models have recently been proposed to accommodate the fact that transposed-letter stimuli like jugde or caniso are perceptually very close to their base words. Methodology Here we examined how letter position coding is attained in the tactile modality via Braille reading. The idea is that Braille word recognition may provide more serial processing than the visual modality, and this may produce differences in the input coding schemes employed to encode letters in written words. To that end, we conducted a lexical decision experiment with adult Braille readers in which the pseudowords were created by transposing/replacing two letters. Principal Findings We found a word-frequency effect for words. In addition, unlike parallel experiments in the visual modality, we failed to find any clear signs of transposed-letter confusability effects. This dissociation highlights the differences between modalities. Conclusions The present data argue against models of letter position coding that assume that transposed-letter effects (in the visual modality) occur at a relatively late, abstract locus. PMID:23071522

Beverton-Holt discrete pest management models with pulsed chemical control and evolution of pesticide resistance

NASA Astrophysics Data System (ADS)

Liang, Juhua; Tang, Sanyi; Cheke, Robert A.

2016-07-01

Pest resistance to pesticides is usually managed by switching between different types of pesticides. The optimal switching time, which depends on the dynamics of the pest population and on the evolution of the pesticide resistance, is critical. Here we address how the dynamic complexity of the pest population, the development of resistance and the spraying frequency of pulsed chemical control affect optimal switching strategies given different control aims. To do this, we developed novel discrete pest population growth models with both impulsive chemical control and the evolution of pesticide resistance. Strong and weak threshold conditions which guarantee the extinction of the pest population, based on the threshold values of the analytical formula for the optimal switching time, were derived. Further, we addressed switching strategies in the light of chosen economic injury levels. Moreover, the effects of the complex dynamical behaviour of the pest population on the pesticide switching times were also studied. The pesticide application period, the evolution of pesticide resistance and the dynamic complexity of the pest population may result in complex outbreak patterns, with consequent effects on the pesticide switching strategies.

K-Band Latching Switches

NASA Technical Reports Server (NTRS)

Piotrowski, W. S.; Raue, J. E.

1984-01-01

Design, development, and tests are described for two single-pole-double-throw latching waveguide ferrite switches: a K-band switch in WR-42 waveguide and a Ka-band switch in WR-28 waveguide. Both switches have structurally simple junctions, mechanically interlocked without the use of bonding materials; they are impervious to the effects of thermal, shock, and vibration stresses. Ferrite material for the Ka-band switch with a proper combination of magnetic and dielectric properties was available and resulted in excellent low loss, wideband performance. The high power handling requirement of the K-band switch limited the choice of ferrite to nickel-zinc compositions with adequate magnetic properties, but with too low relative dielectric constant. The relative dielectric constant determines the junction dimensions for given frequency responses. In this case the too low value unavoidably leads to a larger than optimum junction volume, increasing the insertion loss and restricting the operating bandwidth. Efforts to overcome the materials-related difficulties through the design of a composite junction with increased effective dielectric properties efforts to modify the relative dielectric constant of nickel-zinc ferrite are examined.

The modality and redundancy effects in multimedia learning in children with dyslexia.

PubMed

Knoop-van Campen, Carolien A N; Segers, Eliane; Verhoeven, Ludo

2018-05-01

The present study aimed to examine the modality and redundancy effects in multimedia learning in children with dyslexia in order to find out whether their learning benefits from written and/or spoken text with pictures. We compared study time and knowledge gain in 26 11-year-old children with dyslexia and 38 typically reading peers in a within-subjects design. All children were presented with a series of user-paced multimedia lessons in 3 conditions: pictorial information presented with (a) written text, (b) audio, or (c) combined text and audio. We also examined whether children's learning outcomes were related to their working memory. With respect to study time, we found modality and reversed redundancy effects. Children with dyslexia spent more time learning in the text condition, compared with the audio condition and the combined text-and-audio condition. Regarding knowledge gain, no modality or redundancy effects were evidenced. Although the groups differed on working memory, it did not influence the modality or redundancy effect on study time or knowledge gain. In multimedia learning, it thus is more efficient to provide children with dyslexia with audio or with auditory support. Copyright © 2018 John Wiley & Sons, Ltd.

[Cost-effectiveness of multiple screening modalities on breast cancer in Chinese women from Shanghai].

PubMed

Wu, F; Mo, M; Qin, X X; Fang, H; Zhao, G M; Liu, G Y; Chen, Y Y; Cao, Z G; Yan, Y J; Lyu, L L; Xu, W H; Shao, Z M

2017-12-10

Objective: To determine the most cost-effective modality for breast cancer screening in women living in Shanghai. Methods: A Markov model for breast cancer was redeveloped based on true effect which was derived from a project for detection of women at high risk of breast cancer and an organized breast cancer screening program conducted simultaneously in Minhang district, Shanghai, during 2008 to 2012. Parameters of the model were derived from literatures. General principles related to cost-effectiveness analysis were used to compare the costs and effects of 12 different screening modalities in a simulated cohort involving 100 000 women aged 45 years. Incremental cost-effectiveness ratio (ICER) was used to determine the most cost-effective modality. Sensitivity analysis was conducted to evaluate how these factors affected the estimated cost-effectiveness. Results: The modality of biennial CBE followed by ultrasonic and mammography among those with positive CBE was observed as the most cost-effective one. The costs appeared as 182 526 Yuan RMB per life year gained and 144 386 Yuan RMB per quality adjusted life-year (QALY) saved, which were within the threshold of 2-3 times of local per capita Gross Domestic Product. Results from sensitivity analysis showed that, due to higher incidence rate of breast cancer in Shanghai, the cost per QALY would be 64 836 Yuan RMB lower in Shanghai than the average level in China. Conclusion: Our research findings showed that the biennial CBE program followed by ultrasonic and mammography for those with positive CBE results might serve as the optimal breast cancer screening modality for Chinese women living in Shanghai, and thus be widely promoted in this population elsewhere.

Disparate bilingual experiences modulate task-switching advantages: A diffusion-model analysis of the effects of interactional context on switch costs.

PubMed

Hartanto, Andree; Yang, Hwajin

2016-05-01

Drawing on the adaptive control hypothesis (Green & Abutalebi, 2013), we investigated whether bilinguals' disparate interactional contexts modulate task-switching performance. Fifty-eight bilinguals within the single-language context (SLC) and 75 bilinguals within the dual-language context (DLC) were compared in a typical task-switching paradigm. Given that DLC bilinguals switch between languages within the same context, while SLC bilinguals speak only one language in one environment and therefore rarely switch languages, we hypothesized that the two groups' stark difference in their interactional contexts of conversational exchanges would lead to differences in switch costs. As predicted, DLC bilinguals showed smaller switch costs than SLC bilinguals. Our diffusion-model analyses suggest that DLC bilinguals' benefits in switch costs are more likely driven by task-set reconfiguration than by proactive interference. Our findings underscore the modulating role of the interactional context of conversational exchanges in task switching. Copyright © 2016 Elsevier B.V. All rights reserved.

The Monty Hall dilemma in pigeons: effect of investment in initial choice.

PubMed

Stagner, Jessica P; Rayburn-Reeves, Rebecca; Zentall, Thomas R

2013-10-01

In the Monty Hall dilemma, humans are initially given a choice among three alternatives, one of which has a hidden prize. After choosing, but before it is revealed whether they have won the prize, they are shown that one of the remaining alternatives does not have the prize. They are then asked whether they want to stay with their original choice or switch to the remaining alternative. Although switching results in obtaining the prize two thirds of the time, humans consistently fail to adopt the optimal strategy of switching even after considerable training. Interestingly, there is evidence that pigeons show more optimal switching performance with this task than humans. Because humans often view even random choices already made as being more valuable than choices not made, we reasoned that if pigeons made a greater investment, it might produce an endowment or ownership effect resulting in more human-like suboptimal performance. On the other hand, the greater investment in the initial choice by the pigeons might facilitate switching behavior by helping them to better discriminate their staying versus switching behavior. In Experiment 1, we examined the effect of requiring pigeons to make a greater investment in their initial choice (20 pecks rather than the usual 1 peck). We found that the increased response requirement facilitated acquisition of the switching response. In Experiment 2, we showed that facilitation of switching due to the increased response requirement did not result from extinction of responding to the initially chosen location.

White-light-controlled resistive switching in ZnO/BaTiO3/C multilayer layer at room temperature

NASA Astrophysics Data System (ADS)

Wang, Junshuai; Liang, Dandan; Wu, Liangchen; Li, Xiaoping; Chen, Peng

2018-07-01

The bipolar resistance switching effect is observed in ZnO/BaTiO3/C structure. The resistance switching behavior can be modulated by white light. The resistance switch states and threshold voltage can be changed when subjected to white light. This research can help explore multi-functional materials and applications in nonvolatile memory device.

Polarization and switching properties of holographic polymer-dispersed liquid-crystal gratings. I. Theoretical model

NASA Astrophysics Data System (ADS)

Sutherland, Richard L.

2002-12-01

Polarization properties and electro-optical switching behavior of holographic polymer-dispersed liquid-crystal (HPDLC) reflection and transmission gratings are studied. A theoretical model is developed that combines anisotropic coupled-wave theory with an elongated liquid-crystal-droplet switching model and includes the effects of a statistical orientational distribution of droplet-symmetry axes. Angle- and polarization-dependent switching behaviors of HPDLC gratings are elucidated, and the effects on dynamic range are described. A new type of electro-optical switching not seen in ordinary polymer-dispersed liquid crystals, to the best of the author's knowledge, is presented and given a physical interpretation. The model provides valuable insight to the physics of these gratings and can be applied to the design of HPDLC holographic optical elements.

Switch Detection in Preschoolers’ Cognitive Flexibility

PubMed Central

Chevalier, Nicolas; Wiebe, Sandra A.; Huber, Kristina L.; Espy, Kimberly Andrews

2011-01-01

The present study addressed the role of switch detection in cognitive flexibility by testing the effect of transition cues (i.e., cues that directly signal the need to switch or maintain a given task goal) in a cued set-shifting paradigm at age 5. Children performed better, especially on switch trials, when transition cues were combined with traditional task cues (i.e., cues that directly signal the relevant task on a given trial), relative to conditions without transition cues. This effect was not influenced by explicit knowledge of transition cues or transition cue transparency, suggesting transition cues did not need to be semantically processed to be beneficial. These findings reveal that young children’s difficulties in set-shifting situations partially stem from failures to monitor for the need to switch. PMID:21353678

[Switching and combining strategies of antidepressant medications].

PubMed

Charpeaud, Thomas; Moliere, Fanny; Bubrovszky, Maxime; Haesebaert, Frédéric; Allaïli, Najib; Bation, Rémy; Nieto, Isabel; Richieri, Raphaëlle; Saba, Ghassen; Bellivier, Frank; Bennabi, Djamila; Holtzmann, Jérôme; Camus, Vincent; Courtet, Philippe; Courvoisier, Pierre; d'Amato, Thierry; Doumy, Olivier; Garnier, Marion; Bougerol, Thierry; Lançon, Christophe; Haffen, Emmanuel; Leboyer, Marion; Llorca, Pierre-Michel; Vaiva, Guillaume; El-Hage, Wissam; Aouizerate, Bruno

2016-03-01

Switching antidepressant medication may be helpful in depressed patients having no benefit from the initial antidepressant treatment. Before considering switching strategy, the initial antidepressant treatment should produce no therapeutic effect after at least 4 weeks of administration at adequate dosage. Choosing an antidepressant of pharmacologically distinct profile fails to consistently demonstrate a significant superiority in terms of effectiveness over the switching to another antidepressant within the same pharmacological class. Augmenting SSRI/SNRIs with mirtazapine/mianserin has become the most recommended strategy of antidepressant combinations. Augmenting SSRI with tricyclic drugs is now a less recommended strategy of antidepressant combinations given the increased risk for the occurrence of pharmacokinetic drug-drug interactions and adverse effects. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Suppression of TFT leakage current effect on active matrix displays by employing a new circular switch

NASA Astrophysics Data System (ADS)

Lee, Jae-Hoon; Park, Hyun-Sang; Jeon, Jae-Hong; Han, Min-Koo

2008-03-01

We have proposed a new poly-Si TFT pixel, which can suppress TFT leakage current effect on active matrix organic diode (AMOLED) displays, by employing a new circular switching TFT and additional signal line for compensating the leakage current. When the leakage current of switching TFT is increased, the VGS of the current driving TFT in the proposed pixel is not altered by the variable data voltages due to the circular switching TFT. Our simulation results show that OLED current variation of the proposed pixel can be suppressed less than 3%, while that of conventional pixel exceeds 30%. The proposed pixel may be suitable to suppress the leakage current effect on AMOLED display.

Effect of oxygen concentration and metal electrode on the resistive switching in MIM capacitors with transition metal oxides

NASA Astrophysics Data System (ADS)

Spassov, D.; Paskaleva, A.; Fröhlich, K.; Ivanov, Tz

2017-01-01

The influence of the oxygen content in the dielectric layer and the effect of the bottom electrode on the resistive switching in Au/Pt/TaOx/TiN and Au/Pt/TaOx/Ta structures have been studied. The sputtered TaOx layers have been prepared by using oxygen concentrations of 10 or 7% O 2 in the Ar+O2 working ambient as well as by a gradual variation of the O2 content in the deposition process from 5 to 10%. Two deposition regimes for TiN electrodes have been investigated: reactive sputtering of Ti target in Ar+N2 ambient, and sputtering of TiN target in pure Ar. Bipolar resistive switching behavior is observed in all examined structures. It is demonstrated that the resistive switching effect is affected by the oxygen content in the working ambient as well as by the type and the deposition conditions of the bottom electrodes. Most stable effect, with ON/OFF ratio above 100 is obtained in TaOx deposited with variable O2 content in the ambient. The obtained switching voltage between the high resistive and low resistive state (SET) is about -1.5 V and the reverse changeover (RESET) is ∼2 V. A well pronounced resistive switching is achieved with reactively sputtered TiN while for the other bottom electrodes the effect is negligible.

Attention switching after dietary brain 5-HT challenge in high impulsive subjects.

PubMed

Markus, C Rob; Jonkman, Lisa M

2007-09-01

High levels of impulsivity have adverse effects on performance in cognitive tasks, particularLy in those tasks that require high attention investment. Furthermore, both animal and human research has indicated that reduced brain serotonin (5-HT) function is associated with increases in impulsive behaviour or decreased inhibition ability, but the effects of 5-HT challenge have not yet been investigated in subjects vulnerable to impulsivity. The present study aimed to investigate whether subjects with high trait impulsivity perform worse than low impulsive subjects in a task switching paradigm in which they have to rapidly shift their attention between two response rules, and to investigate the influence of a 5-HT enhancing diet. Healthy subjects with high ( n = 19) and low (n = 18) trait impulsivity scores participated in a double-blind placebo-controlled study. All subjects performed the attention switch task in the morning following breakfast containing either tryptophan-rich alpha-lactalbumin (4.8 g/100 g TRP) or placebo protein (1.4 g/100 g TRP). Whereas there were no baseline differences between high and low impulsive subjects in task switching abilities, high impulsive subjects made significantly more switch errors and responded slower after dietary 5-HT stimulation, whereas no dietary effects were found on task switching performance in low-impulsive subjects. The deterioration in task switching performance induced by the 5-HT enhancing diet in high impulsive subjects was suggested to be established by general arousal/attention-reducing effects of 5-HT, which might have a larger impact in high impulsive subjects due to either different brain circuitry involved in task switching in this group or lower baseline arousal levels.

The risks and benefits of switching patients with schizophrenia or schizoaffective disorder from two to one antipsychotic medication: a randomized controlled trial.

PubMed

Constantine, Robert J; Andel, Ross; McPherson, Marie; Tandon, Rajiv

2015-08-01

Despite little evidence to support its use and practice guidelines discouraging the practice, antipsychotic polypharmacy is widely prevalent in schizophrenia. This randomized controlled trial studied the effects of switching patients stable on two antipsychotic medications to one antipsychotic medication. 104 adult outpatients with schizophrenia from 7 community mental health centers clinically stable on concurrent treatment with 2 antipsychotics were randomly assigned to stay on polypharmacy or to switch to antipsychotic monotherapy. Participants were followed for 1-year with assessments of symptoms and side effects occurring every 60days (7 total assessments). We examined differences in time trajectories in symptoms (PANSS, CGI) and side effects (EPS, metabolic, other) as a function of group assignment (switch vs. stay) and time, using intention-to-treat analysis. Participants who switched to antipsychotic monotherapy experienced greater increases in symptoms than stay patients. These differences emerged in the second 6months of the trial. All-cause discontinuation rates over the 1-year trial were higher in the switch-to-monotherapy group than in the stay-on-polypharmacy group (42% vs. 13%; p<0.01). There were no differences in change over time in any of the side effect measures, except that stay patients experienced a greater decrease in Simpson Angus total scores than switch patients. Clinicians should be cautious in switching patients with chronic schizophrenia who are stable on 2 antipsychotics to one antipsychotic. Given the challenges in discontinuing antipsychotic polypharmacy, adequate trials of evidence-based treatments such as clozapine and long-acting injectable antipsychotics should be undertaken in inadequately responsive schizophrenia patients before moving to antipsychotic polypharmacy. Copyright © 2015 Elsevier B.V. All rights reserved.

Vibration sensing in flexible structures using a distributed-effect modal domain optical fiber sensor

NASA Technical Reports Server (NTRS)

Reichard, Karl M.; Lindner, Douglas K.; Claus, Richard O.

1991-01-01

Modal domain optical fiber sensors have recently been employed in the implementation of system identification algorithms and the closed-loop control of vibrations in flexible structures. The mathematical model of the modal domain optical fiber sensor used in these applications, however, only accounted for the effects of strain in the direction of the fiber's longitudinal axis. In this paper, we extend this model to include the effects of arbitrary stress. Using this sensor model, we characterize the sensor's sensitivity and dynamic range.

Perceptual learning in temporal discrimination: asymmetric cross-modal transfer from audition to vision.

PubMed

Bratzke, Daniel; Seifried, Tanja; Ulrich, Rolf

2012-08-01

This study assessed possible cross-modal transfer effects of training in a temporal discrimination task from vision to audition as well as from audition to vision. We employed a pretest-training-post-test design including a control group that performed only the pretest and the post-test. Trained participants showed better discrimination performance with their trained interval than the control group. This training effect transferred to the other modality only for those participants who had been trained with auditory stimuli. The present study thus demonstrates for the first time that training on temporal discrimination within the auditory modality can transfer to the visual modality but not vice versa. This finding represents a novel illustration of auditory dominance in temporal processing and is consistent with the notion that time is primarily encoded in the auditory system.

TRPV1, TRPA1, and TRPM8 channels in inflammation, energy redirection, and water retention: role in chronic inflammatory diseases with an evolutionary perspective.

PubMed

Straub, Rainer H

2014-09-01

Chronic inflammatory diseases are accompanied by a systemic response of the body, necessary to redirect energy-rich fuels to the activated immune system and to induce volume expansion. The systemic response is switched on by two major pathways: (a) circulating cytokines enter the brain, and (b) signals via sensory nerve fibers are transmitted to the brain. Concerning item b, sensory nerve terminals are equipped with a multitude of receptors that sense temperature, inflammation, osmolality, and pain. Thus, they can be important to inform the brain about peripheral inflammation. Central to these sensory modalities are transient receptor potential channels (TRP channels) on sensory nerve endings. For example, TRP vanilloid 1 (TRPV1) can be activated by heat, inflammatory factors (e.g., protons, bradykinin, anandamide), hyperosmolality, pungent irritants, and others. TRP channels are multimodal switches that transmit peripheral signals to the brain, thereby inducing a systemic response. It is demonstrated how and why these TRP channels (TRPV1, TRP ankyrin type 1 (TRPA1), and TRP melastatin type 8 (TRPM8)) are important to start up a systemic response of energy expenditure, energy allocation, and water retention and how this is linked to a continuously activated immune system in chronic inflammatory diseases.

The protein kinase Mζ network as a bistable switch to store neuronal memory.

PubMed

Ogasawara, Hideaki; Kawato, Mitsuo

2010-12-31

Protein kinase Mζ (PKMζ), the brain-specific, atypical protein kinase C isoform, plays a key role in long-term maintenance of memory. This molecule is essential for long-term potentiation of the neuron and various modalities of learning such as spatial memory and fear conditioning. It is unknown, however, how PKMζ stores information for long periods of time despite molecular turnover. We hypothesized that PKMζ forms a bistable switch because it appears to constitute a positive feedback loop (PKMζ induces its local synthesis) part of which is ultrasensitive (PKMζ stimulates its synthesis through dual pathways). To examine this hypothesis, we modeled the biochemical network of PKMζ with realistic kinetic parameters. Bifurcation analyses of the model showed that the system maintains either the up state or the down state according to previous inputs. Furthermore, the model was able to reproduce a variety of previous experimental results regarding synaptic plasticity and learning, which suggested that it captures the essential mechanism for neuronal memory. We proposed in vitro and in vivo experiments that would critically examine the validity of the model and illuminate the pivotal role of PKMζ in synaptic plasticity and learning. This study revealed bistability of the PKMζ network and supported its pivotal role in long-term storage of memory.

Assessment of an interactive voice response system for identifying falls in a statewide sample of older adults.

PubMed

Albert, Steven M; King, Jennifer; Keene, Robert M

2015-02-01

Interactive voice response (IVR) systems offer great advantages for data collection in large, geographically dispersed samples involving frequent contact. We assessed the quality of IVR data collected from older respondents participating in a statewide falls prevention program evaluation in Pennsylvania in 2010-12. Participants (n=1834) were followed up monthly for up to 10 months to compare respondents who completed all, some, or no assessments in the IVR system. Validity was assessed by examining IVR-reported falls incidence relative to baseline in-person self-report and performance assessment of balance. While a third of the sample switched from IVR to in-person calls over follow-up, IVR interviews were successfully used to complete 68.1% of completed monthly assessments (10,511/15,430). Switching to in-person interviews was not associated with measures of participant function or cognition. Both self-reported (p<.0001) and performance assessment of balance (p=.05) at baseline were related to falls incidence. IVR is a productive modality for falls research among older adults. Future research should establish what level of initial personal research contact is optimal for boosting IVR completion rates and what research domains are most appropriate for this kind of contact. Copyright © 2014 Elsevier Inc. All rights reserved.

Switch junction sequences in PMS2-deficient mice reveal a microhomology-mediated mechanism of Ig class switch recombination

PubMed Central

Ehrenstein, Michael R.; Rada, Cristina; Jones, Anne-Marie; Milstein, César; Neuberger, Michael S.

2001-01-01

Isotype switching involves a region-specific, nonhomologous recombinational deletion that has been suggested to occur by nonhomologous joining of broken DNA ends. Here, we find increased donor/acceptor homology at switch junctions from PMS2-deficient mice and propose that class switching can occur by microhomology-mediated end-joining. Interestingly, although isotype switching and somatic hypermutation show many parallels, we confirm that PMS2 deficiency has no major effect on the pattern of nucleotide substitutions generated during somatic hypermutation. This finding is in contrast to MSH2 deficiency. With MSH2, the altered pattern of switch recombination and hypermutation suggests parallels in the mechanics of the two processes, whereas the fact that PMS2 deficiency affects only switch recombination may reflect differences in the pathways of break resolution. PMID:11717399

Effect of Electronegativity on Bipolar Resistive Switching in a WO3-Based Asymmetric Capacitor Structure.

PubMed

Kim, Jongmin; Inamdar, Akbar I; Jo, Yongcheol; Woo, Hyeonseok; Cho, Sangeun; Pawar, Sambhaji M; Kim, Hyungsang; Im, Hyunsik

2016-04-13

This study investigates the transport and switching time of nonvolatile tungsten oxide based resistive-switching (RS) memory devices. These devices consist of a highly resistive tungsten oxide film sandwiched between metal electrodes, and their RS characteristics are bipolar in the counterclockwise direction. The switching voltage, retention, endurance, and switching time are strongly dependent on the type of electrodes used, and we also find quantitative and qualitative evidence that the electronegativity (χ) of the electrodes plays a key role in determining the RS properties and switching time. We also propose an RS model based on the role of the electronegativity at the interface.

Rotaxane liquid crystals with variable length: The effect of switching efficiency on the isotropic-nematic transition

NASA Astrophysics Data System (ADS)

He, Hao; Sevick, Edith M.; Williams, David R. M.

2018-04-01

We examine a solution of non-adaptive two-state rotaxane molecules which can switch from a short state of length L to a long state of length qL, using statistical thermodynamics. This molecular switching is externally driven and can result in an isotropic-nematic phase transition without altering temperature and concentration. Here we concentrate on the limitation imposed by switching inefficiency, i.e., on the case where molecular switching is not quantitative, leading to a solution of rotaxanes in different states. We present switching diagrams that can guide in the design of rotaxanes which affect a macroscopic phase change.

Power-Switching Circuit

NASA Technical Reports Server (NTRS)

Praver, Gerald A.; Theisinger, Peter C.; Genofsky, John

1987-01-01

Functions of circuit breakers, meters, and switches combined. Circuit that includes power field-effect transistors (PFET's) provides on/off switching, soft starting, current monitoring, current tripping, and protection against overcurrent for 30-Vdc power supply at normal load currents up to 2 A. Has no moving parts.

Effect of residual stress on modal patterns of MEMS vibratory gyroscope

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

Dutta, Shankar, E-mail: shankardutta77@gmail.com; Panchal, Abha; Kumar, Manoj

Deep boron diffusion often induces residual stress in bulk micromachined MEMS structures, which may affect the MEMS devices operation. In this study, we studied the modal patterns of MEMS vibratory gyroscope under the residual stress (100 – 1000 MPa). Modal patterns and modal frequencies of the gyro are found to be dependent on the residual stress values. Without any residual stress, the modal frequencies drive and sense modeswere found to be 20.06 kHz and 20.36 kHz respectively. In presence of 450 MPa residual stress, the modal frequencies of the drive and sense modes were changed to 42.75 kHz and 43.07 kHz respectively.

Switching between global and local levels: the level repetition effect and its hemispheric asymmetry

PubMed Central

Kéïta, Luc; Bedoin, Nathalie; Burack, Jacob A.; Lepore, Franco

2014-01-01

The global level of hierarchical stimuli (Navon’s stimuli) is typically processed quicker and better than the local level; further differential hemispheric dominance is described for local (left hemisphere, LH) and global (right hemisphere, RH) processing. However, neuroimaging and behavioral data indicate that stimulus category (letter or object) could modulate the hemispheric asymmetry for the local level processing. Besides, when the targets are unpredictably displayed at the global or local level, the participant has to switch between levels, and the magnitude of the switch cost increases with the number of repeated-level trials preceding the switch. The hemispheric asymmetries associated with level switching is an unresolved issue. LH areas may be involved in carrying over the target level information in case of level repetition. These areas may also largely participate in the processing of level-changed trials. Here we hypothesized that RH areas underly the inhibitory mechanism performed on the irrelevant level, as one of the components of the level switching process. In an experiment using a within-subject design, hierarchical stimuli were briefly presented either to the right or to the left visual field. 32 adults were instructed to identify the target at the global or local level. We assessed a possible RH dominance for the non-target level inhibition by varying the attentional demands through the manipulation of level repetitions (two or gour repeated-level trials before the switch). The behavioral data confirmed a LH specialization only for the local level processing of letter-based stimuli, and detrimental effect of increased level repetitions before a switch. Further, data provides evidence for a RH advantage in inhibiting the non-target level. Taken together, the data supports the notion of the existence of multiple mechanisms underlying level-switch effects. PMID:24723903

Cognitive and Affective Changes in Mild to Moderate Alzheimer’s Disease Patients Undergoing Switch of Cholinesterase Inhibitors: A 6-Month Observational Study

PubMed Central

Spalletta, Gianfranco; Caltagirone, Carlo; Padovani, Alessandro; Sorbi, Sandro; Attar, Mahmood; Colombo, Delia; Cravello, Luca

2014-01-01

Patients with Alzheimer’s disease after an initial response to cholinesterase inhibitors may complain a later lack of efficacy. This, in association with incident neuropsychiatric symptoms, may worsen patient quality of life. Thus, the switch to another cholinesterase inhibitor could represent a valid therapeutic strategy. The aim of this study was to investigate the effectiveness of the switch from one to another cholinesterase inhibitor on cognitive and affective symptoms in mild to moderate Alzheimer disease patients. Four hundred twenty-three subjects were included from the EVOLUTION study, an observational, longitudinal, multicentre study conducted on Alzheimer disease patients who switched to different cholinesterase inhibitor due either to lack/loss of efficacy or response, reduced tolerability or poor compliance. All patients underwent cognitive and neuropsychiatric assessments, carried out before the switch (baseline), and at 3 and 6-month follow-up. A significant effect of the different switch types was found on Mini-Mental State Examination score during time, with best effectiveness on mild Alzheimer’s disease patients switching from oral cholinesterase inhibitors to rivastigmine patch. Depressive symptoms, when measured using continuous Neuropsychiatric Inventory values, decreased significantly, while apathy symptoms remained stable over the 6 months after the switch. However, frequency of both depression and apathy, when measured categorically using Neuropsychiatric Inventory cut-off scores, did not change significantly during time. In mild to moderate Alzheimer disease patients with loss of efficacy and tolerability during cholinesterase inhibitor treatment, the switch to another cholinesterase inhibitor may represent an important option for slowing cognitive deterioration. The evidence of apathy stabilization and the positive tendency of depressive symptom improvement should definitively be confirmed in double-blind controlled studies. PMID:24586603

Initial antihypertensive prescription and switching: a 5 year cohort study from 250,851 patients.

PubMed

Wong, Martin C S; Tam, Wilson W S; Cheung, Clement S K; Tong, Ellen L H; Sek, Antonio C H; John, George; Cheung, N T; Yan, Bryan P Y; Yu, C M; Leeder, Stephen; Griffiths, Sian

2013-01-01

Adverse effects of antihypertensive therapy incur substantial cost. We evaluated whether any major classes of antihypertensive drugs were significantly associated with switching as a proxy measure of medication side effects in a large Chinese population in Hong Kong. From a clinical database, all adult patients newly prescribed an antihypertensive mono-therapy in Hong Kong between the years 2001-2003 and 2005 were included. Those who paid only one visit, died or stayed in the cohort for <180 days after the prescription, or prescribed more than one antihypertensive agent were excluded. The factors associated with switching at 180 days were evaluated by multivariate regression analyses. Age, gender, payment status, service type, district of residence, drug class, systolic and diastolic blood pressure levels were predictor variables. From 250,851 subjects, 159,813 patients were eligible. A total of 6,163 (3.9%) switched their medications within 180 days. Patients prescribed thiazide diuretics had the highest switching rate (5.6%), followed by ACEIs (4.5%), CCBs (4.4%) and beta-blockers (3.2%). When compared with ACEIs, patients on thiazide diuretics were significantly more likely to be switchers (adjusted odds ratio [AOR] 1.49, 95% C.I. 1.31-1.69, p<0.001), whilst patients prescribed CCBs and beta-blockers were similarly likely to have switching. Following these patients up for 5 years showed that thiazide had the most marked increase in switching rate. The higher rates of switching among thiazide diuretics in this study might raise a probably greater incidence of their adverse effects in this Chinese population, yet other factors might also influence switching rates. Patients prescribed thiazide diuretics for longer term should be observed for their intolerability.

Improved body weight and metabolic outcomes in overweight or obese psychiatric patients switched to amisulpride from other atypical antipsychotics.

PubMed

Lin, Chao-Cheng; Bai, Ya-Mei; Wang, Ying-Chieh; Chen, Tzu-Ting; Lai, I-Ching; Chen, Jen-Yeu; Chen, Shiow-Yi; Gau, Susan S F; Liou, Ying-Jay

2009-12-01

Switching to a different second-generation antipsychotic (SGA) with a lower risk of weight gain is recommended for overweight or obese psychiatric patients undergoing SGA treatment. However, there have been no complete reports regarding the long-term metabolic effects of switching to amisulpride. In this open-label 1-year study, we investigated the effects on body weight and other metabolic profiles when psychiatric patients treated with another SGA were switched to amisulpride treatment. Forty-six schizophrenia or schizoaffective inpatients with a body mass index greater than 27 kg/m were enrolled in the switch group. These patients were cross-titrated to amisulpride treatment and followed up for 1 year prospectively. Another 46 inpatients matched with the baseline body mass index of those in the switch group were enrolled as the control group retrospectively. The results showed that the switch group had greater weight loss than the control group (7.80 +/- 6.67 vs 2.60 +/- 6.23 kg, respectively; repeated-measure analysis of variance, P < 0.0005). During the treatment course, the amisulpride-treated patients showed significantly decreased fasting triglyceride, total cholesterol, glucose, and insulin resistance levels; decreased diastolic blood pressure and pulse rate; and a significant increase in high-density lipoprotein cholesterol levels after switching to amisulpride (all with a P < 0.05). The prevalence of metabolic syndrome in amisulpride-treated patients also decreased significantly from 65.2% to 30.4% (McNemar test, P < 0.0005). These findings suggest that switching to amisulpride could be an effective treatment of overweight or obese psychiatric patients treated previously with other SGAs.

The impact of different cross-training modalities on performance and injury-related variables in high school cross country runners.

PubMed

Paquette, Max R; Peel, Shelby A; Smith, Ross E; Temme, Mark; Dwyer, Jeffrey N

2017-11-29

There are many different types of aerobic cross-training modalities currently available. It is important to consider the effects that these different modalities have on running performance and injury risks. The purpose of this study was to compare movement quality, running economy and performance, injury-related biomechanical variables and, hip muscle strength before and after training with different cross-training modalities in high school runners. Thirty-one high school male runners trained for four weeks in one of three cross-training modalities, in addition to a running-only (RUN, n=9) group, for which training sessions replaced two easy runs per week: cycling (CYCLE; n=6), indoor elliptical (ELLIP; n=7) and, outdoor elliptical bike (EBIKE; n=9). Functional movement screen (FMS), running economy (RE), 3,000m performance, hip kinematics, hip muscle strength were assessed. Paired t-tests and Cohen's d effect sizes were used to assess mean differences for each variable before and after training within each group. EBIKE training was the only modality that improved FMS scores (d = 1.36) and RE before and after training (d = 0.48). All groups showed improvements in 3,000m performance but large effects were only found for the CYCLE (d = 1.50) and EBIKE (d = 1.41) groups. RUN (d = 1.25), CYCLE (d = 1.17) and, EBIKE (d = 0.82) groups showed improvements in maximal hip extensor strength. Outdoor cycling and elliptical bike cross-training may be the most effective cross-training modalities to incorporate in early season training to improve running performance in high school runners.

A method for determining the actual rate of orientation switching of DNA self-assembled monolayers using optical and electrochemical frequency response analysis.

PubMed

Casanova-Moreno, J; Bizzotto, D

2015-02-17

Electrostatic control of the orientation of fluorophore-labeled DNA strands immobilized on an electrode surface has been shown to be an effective bioanalytical tool. Modulation techniques and later time-resolved measurements were used to evaluate the kinetics of the switching between lying and standing DNA conformations. These measurements, however, are the result of a convolution between the DNA "switching" response time and the other frequency limited responses in the measurement. In this work, a method for analyzing the response of a potential driven DNA sensor is presented by calculating the potential effectively dropped across the electrode interface (using electrochemical impedance spectroscopy) as opposed to the potential applied to the electrochemical cell. This effectively deconvolutes the effect of the charging time on the observed frequency response. The corrected response shows that DNA is able to switch conformation faster than previously reported using modulation techniques. This approach will ensure accurate measurements independent of the electrochemical system, removing the uncertainty in the analysis of the switching response, enabling comparison between samples and measurement systems.

Influence of affective valence on working memory processes.

PubMed

Gotoh, Fumiko

2008-02-01

Recent research has revealed widespread effects of emotion on cognitive function and memory. However, the influence of affective valence on working or short-term memory remains largely unexplored. In two experiments, the present study examined the predictions that negative words would capture attention, that attention would be difficult to disengage from such negative words, and that the cost of attention switching would increase the time required to update information in working memory. Participants switched between two concurrent working memory tasks: word recognition and a working memory digit updating task. Experiment 1 showed substantial switching cost for negative words, relative to neutral words. Experiment 2 replicated the first experiment, using a self-report measure of anxiety to examine if switching cost is a function of an anxiety-related attention bias. Results did not support this hypothesis. In addition, Experiment 2 revealed switch costs for positive words without the effect of the attention bias from anxiety. The present study demonstrates the effect of affective valence on a specific component of working memory. Moreover, findings suggest why affective valence effects on working memory have not been found in previous research.

Qualitative Differences between Bilingual Language Control and Executive Control: Evidence from Task-Switching

PubMed Central

Calabria, Marco; Hernández, Mireia; Branzi, Francesca M.; Costa, Albert

2012-01-01

Previous research has shown that highly proficient bilinguals have comparable switch costs in both directions when they switch between languages (L1 and L2), the so-called “symmetrical switch cost” effect. Interestingly, the same symmetry is also present when they switch between L1 and a much weaker L3. These findings suggest that highly proficient bilinguals develop a language control system that seems to be insensitive to language proficiency. In the present study, we explore whether the pattern of symmetrical switch costs in language switching tasks generalizes to a non-linguistic switching task in the same group of highly proficient bilinguals. The end goal of this is to assess whether bilingual language control (bLC) can be considered as subsidiary to domain-general executive control (EC). We tested highly proficient Catalan–Spanish bilinguals both in a linguistic switching task and in a non-linguistic switching task. In the linguistic task, participants named pictures in L1 and L2 (Experiment 1) or L3 (Experiment 2) depending on a cue presented with the picture (a flag). In the non-linguistic task, the same participants had to switch between two card sorting rule-sets (color and shape). Overall, participants showed symmetrical switch costs in the linguistic switching task, but not in the non-linguistic switching task. In a further analysis, we observed that in the linguistic switching task the asymmetry of the switch costs changed across blocks, while in the non-linguistic switching task an asymmetrical switch cost was observed throughout the task. The observation of different patterns of switch costs in the linguistic and the non-linguistic switching tasks suggest that the bLC system is not completely subsidiary to the domain-general EC system. PMID:22275905

The modeling of MMI structures for signal processing applications

NASA Astrophysics Data System (ADS)

Le, Thanh Trung; Cahill, Laurence W.

2008-02-01

Microring resonators are promising candidates for photonic signal processing applications. However, almost all resonators that have been reported so far use directional couplers or 2×2 multimode interference (MMI) couplers as the coupling element between the ring and the bus waveguides. In this paper, instead of using 2×2 couplers, novel structures for microring resonators based on 3×3 MMI couplers are proposed. The characteristics of the device are derived using the modal propagation method. The device parameters are optimized by using numerical methods. Optical switches and filters using Silicon on Insulator (SOI) then have been designed and analyzed. This device can become a new basic component for further applications in optical signal processing. The paper concludes with some further examples of photonic signal processing circuits based on MMI couplers.

Superresolution microscopy with transient binding.

PubMed

Molle, Julia; Raab, Mario; Holzmeister, Susanne; Schmitt-Monreal, Daniel; Grohmann, Dina; He, Zhike; Tinnefeld, Philip

2016-06-01

For single-molecule localization based superresolution, the concentration of fluorescent labels has to be thinned out. This is commonly achieved by photophysically or photochemically deactivating subsets of molecules. Alternatively, apparent switching of molecules can be achieved by transient binding of fluorescent labels. Here, a diffusing dye yields bright fluorescent spots when binding to the structure of interest. As the binding interaction is weak, the labeling is reversible and the dye ligand construct diffuses back into solution. This approach of achieving superresolution by transient binding (STB) is reviewed in this manuscript. Different realizations of STB are discussed and compared to other localization-based superresolution modalities. We propose the development of labeling strategies that will make STB a highly versatile tool for superresolution microscopy at highest resolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Maximum powers of low-loss series-shunt FET RF switches

NASA Astrophysics Data System (ADS)

Yang, Z.; Hu, X.; Yang, J.; Simin, G.; Shur, M.; Gaska, R.

2009-02-01

Low-loss high-power single pole single throw (SPST) monolithic RF switch based on AlGaN/GaN heterojunction field effect transistors (HFETs) demonstrate the insertion loss and isolation of 0.15 dB and 45.9 dB at 0.5 GHz and 0.23 dB and 34.3 dB at 2 GHz. Maximum switching powers are estimated +47 dBm or higher. Factors determining the maximum switching powers are analyzed. Design principles to obtain equally high switching powers in the ON and OFF-states are developed.

Multi-gap high impedance plasma opening switch

DOEpatents

Mason, R.J.

1996-10-22

A high impedance plasma opening switch having an anode and a cathode and at least one additional electrode placed between the anode and cathode is disclosed. The presence of the additional electrodes leads to the creation of additional plasma gaps which are in series, increasing the net impedance of the switch. An equivalent effect can be obtained by using two or more conventional plasma switches with their plasma gaps wired in series. Higher impedance switches can provide high current and voltage to higher impedance loads such as plasma radiation sources. 12 figs.

Encoding Modality Can Affect Memory Accuracy via Retrieval Orientation

ERIC Educational Resources Information Center

Pierce, Benton H.; Gallo, David A.

2011-01-01

Research indicates that false memory is lower following visual than auditory study, potentially because visual information is more distinctive. In the present study we tested the extent to which retrieval orientation can cause a modality effect on memory accuracy. Participants studied unrelated words in different modalities, followed by criterial…

An Investigation on Revealing the Learning Modalities of Undergraduate Students

ERIC Educational Resources Information Center

Ünal, Menderes

2015-01-01

This study investigated learning modalities of undergraduate students in terms of their gender, departments, grades and academic achievements. The modalities/styles (visual, auditory and kinaesthetic) indicate learning preferences and help students find ways to study effectively, reach new information and solve problems. The study was conducted…

Impact of non-medical switching on clinical and economic outcomes, resource utilization and medication-taking behavior: a systematic literature review.

PubMed

Nguyen, Elaine; Weeda, Erin R; Sobieraj, Diana M; Bookhart, Brahim K; Piech, Catherine Tak; Coleman, Craig I

2016-07-01

To evaluate current knowledge of the impact of non-medical switching on clinical and economic outcomes, resource utilization and medication-taking behavior. The literature was searched (Medline and Web of Science, January 2000-November 2015) to identify United States' studies evaluating ≥25 patients and measuring the impact of non-medical switching of drugs (switching to a chemically distinct but similar medication for reasons other than lack of clinical efficacy/response, side effects or poor adherence) on ≥1 clinical, economic, resource utilization or medication-taking behavior outcome. The direction of association between non-medical switching and outcomes was classified as negative or positive if a statistically significant worsening or improvement was reported, or neutral if no significant difference was observed. Twenty-nine studies contributed 96 outcomes (60.4% clinical; 21.9% resource utilization; 13.5% economic; 4.2% medication-taking behavior) within six disease categories (cardio-metabolic, immune-mediated, acid suppression, psychiatric, hormone replacement therapy and pain). The direction of association was more frequently negative (33.3%) or neutral (55.2%) than it was positive (11.5%). Stratified by outcome type, non-medical switching was negatively associated with clinical, economic, healthcare utilization and medication-taking behavior outcomes in 20.7%, 69.2%, 38.1% and 75.0% of cases, respectively; and positively in only 4.8%-17.2% of outcomes subgroups. Of 32 outcomes in patients demonstrating stable/well controlled disease, 68.8% and 31.3% had a negative and neutral direction of association. In patients without demonstrated disease stability, outcomes were negatively, neutrally and positively impacted by non-medical switching in 15.6%, 67.2% and 17.2% of 64 outcomes. Our inability to evaluate specific disease state categories and studies/outcomes received equal weight regardless of sample size or magnitude of effect. Non-medical switching was more often associated with negative or neutral effects than positive effects on an array of important outcomes. Among patients with stable/well controlled disease, non-medical switching was associated with mostly negative effects.

The Ultrathin Limit and Dead-layer Effects in Local Polarization Switching of BiFeO3

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

Maksymovych, Petro; Huijben, Mark; Pan, Minghu

Using piezoresponse force microscopy in ultra-high vacuum, polarization switching has been detected and quantified in epitaxial BiFeO3 films from 200 down to ~ 4 unit cells. Local remnant piezoresponse was used to infer the applied electric field inside the ferroelectric volume, and account for the elusive effect of dead-layers in ultrathin films. The dead-layer manifested itself in the slower than anticipated decrease of the switching bias with film thickness, yielding apparent Kay-Dunn scaling of the switching field, while the statistical analysis of hysteresis loops revealed lateral variation of the dead-layer with sub-10 nm resolution.

Fault-tolerant power distribution system

NASA Technical Reports Server (NTRS)

Volp, Jeffrey A. (Inventor)

1987-01-01

A fault-tolerant power distribution system which includes a plurality of power sources and a plurality of nodes responsive thereto for supplying power to one or more loads associated with each node. Each node includes a plurality of switching circuits, each of which preferably uses a power field effect transistor which provides a diode operation when power is first applied to the nodes and which thereafter provides bi-directional current flow through the switching circuit in a manner such that a low voltage drop is produced in each direction. Each switching circuit includes circuitry for disabling the power field effect transistor when the current in the switching circuit exceeds a preselected value.

Oleanolic acid suppresses aerobic glycolysis in cancer cells by switching pyruvate kinase type M isoforms.

PubMed

Liu, Jia; Wu, Ning; Ma, Leina; Liu, Ming; Liu, Ge; Zhang, Yuyan; Lin, Xiukun

2014-01-01

Warburg effect, one of the hallmarks for cancer cells, is characterized by metabolic switch from mitochondrial oxidative phosphorylation to aerobic glycolysis. In recent years, increased expression level of pyruvate kinase M2 (PKM2) has been found to be the culprit of enhanced aerobic glycolysis in cancer cells. However, there is no agent inhibiting aerobic glycolysis by targeting PKM2. In this study, we found that Oleanolic acid (OA) induced a switch from PKM2 to PKM1, and consistently, abrogated Warburg effect in cancer cells. Suppression of aerobic glycolysis by OA is mediated by PKM2/PKM1 switch. Furthermore, mTOR signaling was found to be inactivated in OA-treated cancer cells, and mTOR inhibition is required for the effect of OA on PKM2/PKM1 switch. Decreased expression of c-Myc-dependent hnRNPA1 and hnRNPA1 was responsible for OA-induced switch between PKM isoforms. Collectively, we identified that OA is an antitumor compound that suppresses aerobic glycolysis in cancer cells and there is potential that PKM2 may be developed as an important target in aerobic glycolysis pathway for developing novel anticancer agents.

Outcomes of tumor necrosis factor inhibitor cycling versus switching to a disease-modifying anti-rheumatic drug with a new mechanism of action among patients with rheumatoid arthritis.

PubMed

Chastek, Benjamin; Becker, Laura K; Chen, Chieh-I; Mahajan, Puneet; Curtis, Jeffrey R

2017-05-01

To examine treatment patterns, treatment effectiveness, and treatment costs for 1 year after patients with rheumatoid arthritis switched from a tumor necrosis factor inhibitor (TNFi) (adalimumab, certolizumab pegol, etanercept, golimumab, or infliximab), either cycling to another TNFi ("TNFi cyclers") or switching to a new mechanism of action (abatacept, tocilizumab, or tofacitinib) ("new MOA switchers"). This retrospective cohort study used administrative claims data for a national insurer. Treatment persistence (without switching again, restarting, or discontinuing), treatment effectiveness (defined below), and costs were assessed for the 12-month post-switch period. Patients were "effectively treated" if they satisfied all six criteria for a treatment effectiveness algorithm (high adherence, no dose increase, no new conventional synthetic disease-modifying anti-rheumatic drug, no subsequent switch in therapy, no new/increased oral glucocorticoids, and <2 glucocorticoid injections). Multivariable logistic models were used to adjust for baseline factors. The database included 581 new MOA switchers and 935 TNFi cyclers. New MOA switchers were 39% more likely than TNFi cyclers to persist after the switch (odds ratio [OR] = 1.39; 95% confidence interval [CI] = 1.12-1.74; p = .003) and 36% less likely to switch therapy again (OR = 0.64; 95% CI = 0.51-0.81; p < .001). New MOA switchers were 43% more likely than TNFi cyclers to be effectively treated (OR = 1.43; 95% CI = 1.11-1.85; p = .006). New MOA switchers had 16% lower drug costs than TNFi cyclers (cost ratio = 0.84; 95% CI = 0.79-0.88; p < .001) and 11% lower total costs of rheumatoid arthritis-related medical care (cost ratio = 0.89; 95% CI = 0.84-0.94; p < .001). Claims payments may not reflect rebates or other cost offsets. Medical and pharmacy claims do not include clinical end-points or reasons that lead to new MOA switching vs TNFi cycling. These results support switching to a new MOA after a patient fails treatment with a TNFi, which is consistent with recent guidelines for the pharmacologic management of established rheumatoid arthritis.

The effects of psychotomimetics and psychomotor stimulants on two schedules promoting response switching in the rat.

PubMed

Evenden, John

2002-10-01

Psychosis and psychotomimetic drugs result in a disorganisation of the structure of thought and behaviour. Normalising these is one of the objects of antipsychotic therapy, and methods for predicting such a therapeutic effect would be of value. The effects of a number of psychotomimetic agents were examined on the way in which rats distributed responding over two response levers using two different procedures, to assay their effects on behavioural organisation. Previously, amphetamine has been found to increase response switching using these schedules. In the first, the random reinforcement procedure, one of the two levers was selected at random as "correct", and responses on this lever were reinforced with food under a random ratio schedule. No signal was given to distinguish the levers. Responding could also result in the food tray being illuminated, but no food pellet was delivered ("no-food" event). Responses on the second lever ("incorrect") had no programmed consequences. After each food delivery or "no-food" event the levers designated as "correct" and "incorrect" were reassigned at random, and the rat had to open the food tray to restart the schedule. In the second procedure, the rats were required to make 21 responses before a switch between the two levers resulted in food delivery [Fixed Ratio (FR) 21-switch]. The responses making up the FR could be distributed freely between the two levers. Phencyclidine (PCP), scopolamine, caffeine and ethanol increased switching under the random reinforcement procedure, but (+/-)-2,5-dimethoxy-4-iodoamphetamine hydrochloride (DOI) and atropine did not. PCP, caffeine, lysergic acid diethylamide (LSD) and atropine increased switching under the FR21-switch procedure, but ethanol did not. The increases in switching produced by PCP, LSD and the anticholinergics were accompanied by marked reductions in response rate, whereas those produced by amphetamine and caffeine were not. The effects of amphetamine, and PCP were strongly dependent on the baseline probability of switching, those of atropine and caffeine moderately so, and those of LSD and ethanol only weakly so. Of the agents tested, psychomotor stimulants appear to produce the most selective increases in switching. The procedures described here may be useful for assaying the disorganisation of behaviour produced by other psychotomimetics and may have value in the detection of novel antipsychotic drugs.

45^○ sign switching of effective exchange bias due to competing anisotropies in fully epitaxial Co₃FeN/MnN bilayers.

PubMed

Hajiri, Tetsuya; Yoshida, Takuya; Filianina, Mariia; Jaiswal, Samridh; Borie, Benjamin; Asano, H; Zabel, Hartmut; Klaui, Mathias

2017-11-20

We report an unusual angular-dependent exchange bias effect in ferromagnet/antiferromagnet bilayers, where both ferromagnet and antiferromagnet are epitaxially grown. Numerical model calculations predict an approximately 45$^\\circ$ period for the sign switching of the exchange-bias field, depending on the ratio between magnetocrystalline anisotropy and exchange-coupling constant. The switching of the sign is indicative of a competition between a fourfold magnetocrystalline anisotropy of the ferromagnet and a unidirectional anisotropy field of the exchange coupling. This predicted unusual angular-dependent exchange bias and its magnetization switching process are confirmed by measurements on fully epitaxial Co$_3$FeN/MnN bilayers by longitudinal and transverse magneto-optic Kerr effect magnetometry. These results provide a deeper understanding of the exchange coupling phenomena in fully epitaxial bilayers with tailored materials and open up a complex switching energy landscape engineering by anisotropies. © 2017 IOP Publishing Ltd.

Magnetically Delayed Low-Pressure Gas Discharge Switching

DTIC Science & Technology

1993-06-01

the gap, minimizes this effect. It is this version of the low- pressure switch that we are presently studying. Our magnetically delayed low... pressure switch (MDLPS) test-stand was built primarily to support the long-pulse, relativistic klystron (RK) and free electron laser (FEL) work at... pressure switch and compared the performance with and without the saturable inductor. A comparison of typi- cal closure properties is shown in Fig

Influence of hydrostatic pressure on the switching time and switching coefficient of NiZnCo ferrites

NASA Astrophysics Data System (ADS)

Romanowski, S.; Goldberg, S.

1980-04-01

Results of the investigation of the effect of hydrostatic pressure on the pulse performance of NiZnCo ferrites with square hysteresis loop are given. It is stated that with increasing hydrostatic pressure, the threshold field strength increases, the switching coefficient value decreases, while the switching time value may increase monotonically or reach a maximum depending on the magnetizing field strength.

Dynamic Testing and Automatic Repair of Reconfigurable Wiring Harnesses

DTIC Science & Technology

2006-11-27

Switch An M ×N grid of switches configured to provide a M -input, N -output routing network. Permutation Network A permutation network performs an...wiring reduces the effective advantage of their reduced switch count, particularly when considering that regular grids (crossbar switches being a...are connected to. The outline circuit shown in Fig. 20 shows how a suitable ‘discovery probe’ might be implemented. The circuit shows a UART

On modal cross-coupling in the asymptotic modal limit

NASA Astrophysics Data System (ADS)

Culver, Dean; Dowell, Earl

2018-03-01

The conditions under which significant modal cross-coupling occurs in dynamical systems responding to high-frequency, broadband forcing that excites many modes is studied. The modal overlap factor plays a key role in the analysis of these systems as the modal density (the ratio of number of modes to the frequency bandwidth) becomes large. The modal overlap factor is effectively the ratio of the width of a resonant peak (the damping ratio times the resonant frequency) to the average frequency interval between resonant peaks (or rather, the inverse of the modal density). It is shown that this parameter largely determines whether substantial modal cross-coupling occurs in a given system's response. Here, two prototypical systems are considered. The first is a simple rectangular plate whose significant modal cross-coupling is the exception rather than the norm. The second is a pair of rectangular plates attached at a point where significant modal cross-coupling is more likely to occur. We show that, for certain cases of modal density and damping, non-negligible cross coupling occurs in both systems. Under similar circumstances, the constraint force between the two plates in the latter system becomes broadband. The implications of this for using Asymptotic Modal Analysis (AMA) in multi-component systems are discussed.

The Effect of Positive Mood on Flexible Processing of Affective Information.

PubMed

Grol, Maud; De Raedt, Rudi

2017-07-17

Recent efforts have been made to understand the cognitive mechanisms underlying psychological resilience. Cognitive flexibility in the context of affective information has been related to individual differences in resilience. However, it is unclear whether flexible affective processing is sensitive to mood fluctuations. Furthermore, it remains to be investigated how effects on flexible affective processing interact with the affective valence of information that is presented. To fill this gap, we tested the effects of positive mood and individual differences in self-reported resilience on affective flexibility, using a task switching paradigm (N = 80). The main findings showed that positive mood was related to lower task switching costs, reflecting increased flexibility, in line with previous findings. In line with this effect of positive mood, we showed that greater resilience levels, specifically levels of acceptance of self and life, also facilitated task set switching in the context of affective information. However, the effects of resilience on affective flexibility seem more complex. Resilience tended to relate to more efficient task switching when negative information was preceded by positive information, possibly because the presentation of positive information, as well as positive mood, can facilitate task set switching. Positive mood also influenced costs associated with switching affective valence of the presented information. This latter effect was indicative of a reduced impact of no longer relevant negative information and more impact of no longer relevant positive information. Future research should confirm these effects of individual differences in resilience on affective flexibility, considering the affective valence of the presented information. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The effects of aging on conflict detection.

PubMed

Lucci, Giuliana; Berchicci, Marika; Spinelli, Donatella; Taddei, Francesco; Di Russo, Francesco

2013-01-01

Several cognitive changes characterize normal aging; one change regards inhibitory processing and includes both conflict monitoring and response suppression. We attempted to segregate these two aspects within a Go/No-go task, investigating three age categories. Accuracy, response times and event-related potentials (ERPs) were recorded. The ERP data were analyzed, and the Go and No-go trials were separated; in addition, the trials were organized in repeat trials (in which the subjects repeated the action delivered in the previous trial) and switch trials (in which the subjects produced a response opposite to the previous response). We assumed that the switch trials conveyed more conflict than the repeat trials. In general, the behavioral data and slower P3 latencies confirmed the well-known age-related speed/accuracy trade-off. The novel analyses of the repeat vs. switch trials indicated that the age-related P3 slowing was significant only for the high conflict condition; the switch-P3 amplitude increased only in the two older groups. The 'aging switch effect' on the P3 component suggests a failure in the conflict conditions and likely contributes to a generalized dysfunction. The absence of either a switch effect in the young group and the P3 slowing in middle-aged group indicate that switching was not particularly demanding for these participants. The N2 component was less sensitive to the repeat/switch manipulation; however, the subtractive waves also enhanced the age effects in this earlier time window. The topographic maps showed other notable age effects: the frontal No-go N2 was nearly undetectable in the elderly; in the identical time window, a large activity in the posterior and prefrontal scalp regions was observed. Moreover, the prefrontal activity showed a negative correlation with false alarms. These results suggest that the frontal involvement during action suppression becomes progressively dysfunctional with aging, and additional activity was required to reach a good level of accuracy.

Dissociable identity- and modality-specific neural representations as revealed by cross-modal nonspatial inhibition of return.

PubMed

Chi, Yukai; Yue, Zhenzhu; Liu, Yupin; Mo, Lei; Chen, Qi

2014-08-01

There are ongoing debates on whether object concepts are coded as supramodal identity-based or modality-specific representations in the human brain. In this fMRI study, we adopted a cross-modal "prime-neutral cue-target" semantic priming paradigm, in which the prime-target relationship was manipulated along both the identity and the modality dimensions. The prime and the target could refer to either the same or different semantic identities, and could be delivered via either the same or different sensory modalities. By calculating the main effects and interactions of this 2 (identity cue validity: "Identity_Cued" vs. "Identity_Uncued") × 2 (modality cue validity: "Modality_Cued" vs. "Modality_Uncued") factorial design, we aimed at dissociating three neural networks involved in creating novel identity-specific representations independent of sensory modality, in creating modality-specific representations independent of semantic identity, and in evaluating changes of an object along both the identity and the modality dimensions, respectively. Our results suggested that bilateral lateral occipital cortex was involved in creating a new supramodal semantic representation irrespective of the input modality, left dorsal premotor cortex, and left intraparietal sulcus were involved in creating a new modality-specific representation irrespective of its semantic identity, and bilateral superior temporal sulcus was involved in creating a representation when the identity and modality properties were both cued or both uncued. In addition, right inferior frontal gyrus showed enhanced neural activity only when both the identity and the modality of the target were new, indicating its functional role in novelty detection. Copyright © 2014 Wiley Periodicals, Inc.

MR-compatibility assessment of MADPET4: a study of interferences between an SiPM-based PET insert and a 7 T MRI system

NASA Astrophysics Data System (ADS)

Omidvari, Negar; Topping, Geoffrey; Cabello, Jorge; Paul, Stephan; Schwaiger, Markus; Ziegler, Sibylle I.

2018-05-01

Compromises in the design of a positron emission tomography (PET) insert for a magnetic resonance imaging (MRI) system should minimize the deterioration of image quality in both modalities, particularly when simultaneous demanding acquisitions are performed. In this work, the advantages of using individually read-out crystals with high-gain silicon photomultipliers (SiPMs) were studied with a small animal PET insert for a 7 T MRI system, in which the SiPM charge was transferred to outside the MRI scanner using coaxial cables. The interferences between the two systems were studied with three radio-frequency (RF) coil configurations. The effects of PET on the static magnetic field, flip angle distribution, RF noise, and image quality of various MRI sequences (gradient echo, spin echo, and echo planar imaging (EPI) at 1H frequency, and chemical shift imaging at 13C frequency) were investigated. The effects of fast-switching gradient fields and RF pulses on PET count rate were studied, while the PET insert and the readout electronics were not shielded. Operating the insert inside a 1H volume coil, used for RF transmission and reception, limited the MRI to T1-weighted imaging, due to coil detuning and RF attenuation, and resulted in significant PET count loss. Using a surface receive coil allowed all tested MR sequences to be used with the insert, with 45–59% signal-to-noise ratio (SNR) degradation, compared to without PET. With a 1H/13C volume coil inside the insert and shielded by a copper tube, the SNR degradation was limited to 23–30% with all tested sequences. The insert did not introduce any discernible distortions into images of two tested EPI sequences. Use of truncated sinc shaped RF excitation pulses and gradient field switching had negligible effects on PET count rate. However, PET count rate was substantially affected by high-power RF block pulses and temperature variations due to high gradient duty cycles.

BLEACHING MECHANISM OF ORGANIC PHOTOTROPIC SUBSTANCES USED IN RUBY LASERS AS SWITCHES,

DTIC Science & Technology

The bleaching process of organic phototropic switches under the effect of ruby laser emission was examined. The effect of the atomic constants of solutions on the bleaching process is evaluated. (Author)

Multimedia instructions and cognitive load theory: effects of modality and cueing.

PubMed

Tabbers, Huib K; Martens, Rob L; van Merriënboer, Jeroen J G

2004-03-01

Recent research on the influence of presentation format on the effectiveness of multimedia instructions has yielded some interesting results. According to cognitive load theory (Sweller, Van Merriënboer, & Paas, 1998) and Mayer's theory of multimedia learning (Mayer, 2001), replacing visual text with spoken text (the modality effect) and adding visual cues relating elements of a picture to the text (the cueing effect) both increase the effectiveness of multimedia instructions in terms of better learning results or less mental effort spent. The aim of this study was to test the generalisability of the modality and cueing effect in a classroom setting. The participants were 111 second-year students from the Department of Education at the University of Gent in Belgium (age between 19 and 25 years). The participants studied a web-based multimedia lesson on instructional design for about one hour. Afterwards they completed a retention and a transfer test. During both the instruction and the tests, self-report measures of mental effort were administered. Adding visual cues to the pictures resulted in higher retention scores, while replacing visual text with spoken text resulted in lower retention and transfer scores. Only a weak cueing effect and even a reverse modality effect have been found, indicating that both effects do not easily generalise to non-laboratory settings. A possible explanation for the reversed modality effect is that the multimedia instructions in this study were learner-paced, as opposed to the system-paced instructions used in earlier research.

Loss restlessness and gain calmness: durable effects of losses and gains on choice switching.

PubMed

Yechiam, Eldad; Zahavi, Gal; Arditi, Eli

2015-08-01

While the traditional conceptualization of the effect of losses focuses on bias in the subjective weight of losses compared with respective gains, some accounts suggest more global task-related effects of losses. Based on a recent attentional theory, we predicted a positive after-effect of losses on choice switching in later tasks. In two experimental studies, we found increased choice switching rates in tasks with losses compared to tasks with no losses. Additionally, this heightened shifting behavior was maintained in subsequent tasks that do not include losses, a phenomenon we refer to as "loss restlessness." Conversely, gains were found to have an opposite "calming" effect on choice switching. Surprisingly, the loss restlessness phenomenon was observed following an all-losses payoff regime but not after a task with symmetric mixed gains and losses. This suggests that the unresolved mental account following an all-losses regime increases search behavior. Potential implications to macro level phenomena, such as the leverage effect, are discussed.

Modality-specific spectral dynamics in response to visual and tactile sequential shape information processing tasks: An MEG study using multivariate pattern classification analysis.

PubMed

Gohel, Bakul; Lee, Peter; Jeong, Yong

2016-08-01

Brain regions that respond to more than one sensory modality are characterized as multisensory regions. Studies on the processing of shape or object information have revealed recruitment of the lateral occipital cortex, posterior parietal cortex, and other regions regardless of input sensory modalities. However, it remains unknown whether such regions show similar (modality-invariant) or different (modality-specific) neural oscillatory dynamics, as recorded using magnetoencephalography (MEG), in response to identical shape information processing tasks delivered to different sensory modalities. Modality-invariant or modality-specific neural oscillatory dynamics indirectly suggest modality-independent or modality-dependent participation of particular brain regions, respectively. Therefore, this study investigated the modality-specificity of neural oscillatory dynamics in the form of spectral power modulation patterns in response to visual and tactile sequential shape-processing tasks that are well-matched in terms of speed and content between the sensory modalities. Task-related changes in spectral power modulation and differences in spectral power modulation between sensory modalities were investigated at source-space (voxel) level, using a multivariate pattern classification (MVPC) approach. Additionally, whole analyses were extended from the voxel level to the independent-component level to take account of signal leakage effects caused by inverse solution. The modality-specific spectral dynamics in multisensory and higher-order brain regions, such as the lateral occipital cortex, posterior parietal cortex, inferior temporal cortex, and other brain regions, showed task-related modulation in response to both sensory modalities. This suggests modality-dependency of such brain regions on the input sensory modality for sequential shape-information processing. Copyright © 2016 Elsevier B.V. All rights reserved.

Novel polarization diversity without switch duplication of a Si-wire PILOSS optical switch.

PubMed

Tanizawa, Ken; Suzuki, Keijiro; Ikeda, Kazuhiro; Namiki, Shu; Kawashima, Hitoshi

2016-04-04

We demonstrate the compact polarization diversity based on the bidirectional full-port use of a path-independent-insertion-loss (PILOSS) optical switch. A polarization-diversity 4 × 4 strictly non-blocking optical switch is developed using a single thermooptic PILOSS Si-wire switch and fiber-based polarization beam splitters (PBSs) and combiners (PBCs). We measure characteristics of the switch and confirm that the proposed configuration demonstrates the performance in the insertion loss, polarization-dependent loss (PDL), and differential group delay (DGD) comparable with that of a conventional polarization-diversity 4 × 4 PILOSS switch using double switch elements. On the other hand, higher crosstalk is observed. The crosstalk increase is associated with the backward crosstalk at a waveguide intersection based on a directional coupler. The effect of the backward crosstalk on the total crosstalk is estimated, and future prospects are discussed.

An acoustic switch.

PubMed

Vanhille, Christian; Campos-Pozuelo, Cleofé

2014-01-01

The benefits derived from the development of acoustic transistors which act as switches or amplifiers have been reported in the literature. Here we propose a model of acoustic switch. We theoretically demonstrate that the device works: the input signal is totally restored at the output when the switch is on whereas the output signal nulls when the switch is off. The switch, on or off, depends on a secondary acoustic field capable to manipulate the main acoustic field. The model relies on the attenuation effect of many oscillating bubbles on the main travelling wave in the liquid, as well as on the capacity of the secondary acoustic wave to move the bubbles. This model evidences the concept of acoustic switch (transistor) with 100% efficiency. Copyright © 2013 Elsevier B.V. All rights reserved.

Design and implementation of optical switches based on nonlinear plasmonic ring resonators: Circular, square and octagon

NASA Astrophysics Data System (ADS)

Ghadrdan, Majid; Mansouri-Birjandi, Mohammad Ali

2018-05-01

In this paper, all-optical plasmonic switches (AOPS) based on various configurations of circular, square and octagon nonlinear plasmonic ring resonators (NPRR) were proposed and numerically investigated. Each of these configurations consisted of two metal-insulator-metal (MIM) waveguides coupled to each other by a ring resonator (RR). Nonlinear Kerr effect was used to show switching performance of the proposed NPRR. The result showed that the octagon switch structure had lower threshold power and higher transmission ratio than square and circular switch structures. The octagon switch structure had a low threshold power equal to 7.77 MW/cm2 and the high transmission ratio of approximately 0.6. Therefore, the octagon switch structure was an appropriate candidate to be applied in optical integration circuits as an AOPS.

Switching State-Feedback LPV Control with Uncertain Scheduling Parameters

NASA Technical Reports Server (NTRS)

He, Tianyi; Al-Jiboory, Ali Khudhair; Swei, Sean Shan-Min; Zhu, Guoming G.

2017-01-01

This paper presents a new method to design Robust Switching State-Feedback Gain-Scheduling (RSSFGS) controllers for Linear Parameter Varying (LPV) systems with uncertain scheduling parameters. The domain of scheduling parameters are divided into several overlapped subregions to undergo hysteresis switching among a family of simultaneously designed LPV controllers over the corresponding subregion with the guaranteed H-infinity performance. The synthesis conditions are given in terms of Parameterized Linear Matrix Inequalities that guarantee both stability and performance at each subregion and associated switching surfaces. The switching stability is ensured by descent parameter-dependent Lyapunov function on switching surfaces. By solving the optimization problem, RSSFGS controller can be obtained for each subregion. A numerical example is given to illustrate the effectiveness of the proposed approach over the non-switching controllers.

Effects of ambient stimuli on measures of behavioral state and microswitch use in adults with profound multiple impairments.

PubMed

Murphy, Kathleen M; Saunders, Muriel D; Saunders, Richard R; Olswang, Lesley B

2004-01-01

The effects of different types and amounts of environmental stimuli (visual and auditory) on microswitch use and behavioral states of three individuals with profound multiple impairments were examined. The individual's switch use and behavioral states were measured under three setting conditions: natural stimuli (typical visual and auditory stimuli in a recreational situation), reduced visual stimuli, and reduced visual and auditory stimuli. Results demonstrated differential switch use in all participants with the varying environmental setting conditions. No consistent effects were observed in behavioral state related to environmental condition. Predominant behavioral state scores and switch use did not systematically covary with any participant. Results suggest the importance of considering environmental stimuli in relationship to switch use when working with individuals with profound multiple impairments.

An absorptive single-pole four-throw switch using multiple-contact MEMS switches and its application to a monolithic millimeter-wave beam-forming network

NASA Astrophysics Data System (ADS)

Lee, Sanghyo; Kim, Jong-Man; Kim, Yong-Kweon; Kwon, Youngwoo

2009-01-01

In this paper, a new absorptive single-pole four-throw (SP4T) switch based on multiple-contact switching is proposed and integrated with a Butler matrix to demonstrate a monolithic beam-forming network at millimeter waves (mm waves). In order to simplify the switching driving circuit and reduce the number of unit switches in an absorptive SP4T switch, the individual switches were replaced with long-span multiple-contact switches using stress-free single-crystalline-silicon MEMS technology. This approach improves the mechanical stability as well as the manufacturing yield, thereby allowing successful integration into a monolithic beam former. The fabricated absorptive SP4T MEMS switch shows insertion loss less than 1.3 dB, return losses better than 11 dB at 30 GHz and wideband isolation performance higher than 39 dB from 20 to 40 GHz. The absorptive SP4T MEMS switch is integrated with a 4 × 4 Butler matrix on a single chip to implement a monolithic beam-forming network, directing beam into four distinct angles. Array factors from the measured data show that the proposed absorptive SPnT MEMS switch can be effectively used for high-performance mm-wave beam-switching systems. This work corresponds to the first demonstration of a monolithic beam-forming network using switched beams.

The Effect of Basis Selection on Static and Random Acoustic Response Prediction Using a Nonlinear Modal Simulation

NASA Technical Reports Server (NTRS)

Rizzi, Stephen A.; Przekop, Adam

2005-01-01

An investigation of the effect of basis selection on geometric nonlinear response prediction using a reduced-order nonlinear modal simulation is presented. The accuracy is dictated by the selection of the basis used to determine the nonlinear modal stiffness. This study considers a suite of available bases including bending modes only, bending and membrane modes, coupled bending and companion modes, and uncoupled bending and companion modes. The nonlinear modal simulation presented is broadly applicable and is demonstrated for nonlinear quasi-static and random acoustic response of flat beam and plate structures with isotropic material properties. Reduced-order analysis predictions are compared with those made using a numerical simulation in physical degrees-of-freedom to quantify the error associated with the selected modal bases. Bending and membrane responses are separately presented to help differentiate the bases.

Lip-read me now, hear me better later: cross-modal transfer of talker-familiarity effects.

PubMed

Rosenblum, Lawrence D; Miller, Rachel M; Sanchez, Kauyumari

2007-05-01

There is evidence that for both auditory and visual speech perception, familiarity with the talker facilitates speech recognition. Explanations of these effects have concentrated on the retention of talker information specific to each of these modalities. It could be, however, that some amodal, talker-specific articulatory-style information facilitates speech perception in both modalities. If this is true, then experience with a talker in one modality should facilitate perception of speech from that talker in the other modality. In a test of this prediction, subjects were given about 1 hr of experience lipreading a talker and were then asked to recover speech in noise from either this same talker or a different talker. Results revealed that subjects who lip-read and heard speech from the same talker performed better on the speech-in-noise task than did subjects who lip-read from one talker and then heard speech from a different talker.

On the role of verbalization during task set selection: switching or serial order control?

PubMed

Bryck, Richard L; Mayr, Ulrich

2005-06-01

Recent task-switching work in which paper-and-pencil administered single-task lists were compared with task-alternation lists has demonstrated large increases in task-switch costs with concurrent articulatory suppression (AS), implicating a crucial role for verbalization during switching (Baddeley, Chincotta, & Adlam, 2001; Emerson & Miyake, 2003). Experiment 1 replicated this result, using computerized assessment, albeit with much smaller effect sizes than in the original reports. In Experiment 2, AS interference was reduced when a sequential cue (spatial location) that indicated the current position in the sequence of task alternations was given. Finally, in Experiment 3, switch trials and no-switch trials were compared within a block of alternating runs of two tasks. Again, AS interference was obtained mainly when the endogenous sequencing demand was high, and it was comparable for no-switch and switch trials. These results suggest that verbalization may be critical for endogenous maintenance and updating of a sequential plan, rather than exclusively for the actual switching process.

Exploring the repetition bias in voluntary task switching.

PubMed

Mittelstädt, Victor; Dignath, David; Schmidt-Ott, Magdalena; Kiesel, Andrea

2018-01-01

In the voluntary task-switching paradigm, participants are required to randomly select tasks. We reasoned that the consistent finding of a repetition bias (i.e., participants repeat tasks more often than expected by chance) reflects reasonable adaptive task selection behavior to balance the goal of random task selection with the goals to minimize the time and effort for task performance. We conducted two experiments in which participants were provided with variable amount of preview for the non-chosen task stimuli (i.e., potential switch stimuli). We assumed that switch stimuli would initiate some pre-processing resulting in improved performance in switch trials. Results showed that reduced switch costs due to extra-preview in advance of each trial were accompanied by more task switches. This finding is in line with the characteristics of rational adaptive behavior. However, participants were not biased to switch tasks more often than chance despite large switch benefits. We suggest that participants might avoid effortful additional control processes that modulate the effects of preview on task performance and task choice.

Statistical electric field and switching time distributions in PZT 1Nb2Sr ceramics: Crystal- and microstructure effects

NASA Astrophysics Data System (ADS)

Zhukov, Sergey; Kungl, Hans; Genenko, Yuri A.; von Seggern, Heinz

2014-01-01

Dispersive polarization response of ferroelectric PZT ceramics is analyzed assuming the inhomogeneous field mechanism of polarization switching. In terms of this model, the local polarization switching proceeds according to the Kolmogorov-Avrami-Ishibashi scenario with the switching time determined by the local electric field. As a result, the total polarization reversal is dominated by the statistical distribution of the local field magnitudes. Microscopic parameters of this model (the high-field switching time and the activation field) as well as the statistical field and consequent switching time distributions due to disorder at a mesoscopic scale can be directly determined from a set of experiments measuring the time dependence of the total polarization switching, when applying electric fields of different magnitudes. PZT 1Nb2Sr ceramics with Zr/Ti ratios 51.5/48.5, 52.25/47.75, and 60/40 with four different grain sizes each were analyzed following this approach. Pronounced differences of field and switching time distributions were found depending on the Zr/Ti ratios. Varying grain size also affects polarization reversal parameters, but in another way. The field distributions remain almost constant with grain size whereas switching times and activation field tend to decrease with increasing grain size. The quantitative changes of the latter parameters with grain size are very different depending on composition. The origin of the effects on the field and switching time distributions are related to differences in structural and microstructural characteristics of the materials and are discussed with respect to the hysteresis loops observed under bipolar electrical cycling.

Rational Design and Tuning of Functional RNA Switch to Control an Allosteric Intermolecular Interaction.

PubMed

Endoh, Tamaki; Sugimoto, Naoki

2015-08-04

Conformational transitions of biomolecules in response to specific stimuli control many biological processes. In natural functional RNA switches, often called riboswitches, a particular RNA structure that has a suppressive or facilitative effect on gene expression transitions to an alternative structure with the opposite effect upon binding of a specific metabolite to the aptamer region. Stability of RNA secondary structure (-ΔG°) can be predicted based on thermodynamic parameters and is easily tuned by changes in nucleobases. We envisioned that tuning of a functional RNA switch that causes an allosteric interaction between an RNA and a peptide would be possible based on a predicted switching energy (ΔΔG°) that corresponds to the energy difference between the RNA secondary structure before (-ΔG°before) and after (-ΔG°after) the RNA conformational transition. We first selected functional RNA switches responsive to neomycin with predicted ΔΔG° values ranging from 5.6 to 12.2 kcal mol(-1). We then demonstrated a simple strategy to rationally convert the functional RNA switch to switches responsive to natural metabolites thiamine pyrophosphate, S-adenosyl methionine, and adenine based on the predicted ΔΔG° values. The ΔΔG° values of the designed RNA switches proportionally correlated with interaction energy (ΔG°interaction) between the RNA and peptide, and we were able to tune the sensitivity of the RNA switches for the trigger molecule. The strategy demonstrated here will be generally applicable for construction of functional RNA switches and biosensors in which mechanisms are based on conformational transition of nucleic acids.

Research on multi-switch synchronization based on single trigger generator

NASA Astrophysics Data System (ADS)

Geng, Jiuyuan; Cheng, Xinbing; Yang, Jianhua; Yang, Xiao; Chen, Rong

2018-05-01

Multi-switch synchronous operation is an effective approach to provide high-voltage high-current for a high-power device. In this paper, we present a synchronization system with a corona stabilized triggered switch (CSTS) as main switch and an all-solid modularized quasi-square pulse forming system. In addition, this paper provides explanations of low jitter and accurate triggering of CSTS based on streamer theory. Different switches of the module are triggered by an electrical pulse created by a trigger generator, a quasi-square pulse can be created on the load. The experimental results show that it is able to switch voltages in excess of 40kV with nanosecond system jitter for three-module synchronous operation.

The NASA satellite communication 20 x 20 matrix switches

NASA Technical Reports Server (NTRS)

Saunders, A. L.

1983-01-01

The characteristics of two matrix switches designed for high capacity satellite communications systems are described. The switches provide routing between 20 input and 20 output ports at an IF frequency during TDMA operations. Switching speeds of 10 nsec are projected for dual gate GaAs FETs. The two designs differed in the coupling configurations, bandwidth (2.69-1.2 GHz), off-state isolation (-54 to -40 dB), switching speeds (16-37 nsec), and gain ripple (5.3-2.2 dB). Both designs achieved a 2 nsec reconfiguration rate. Further development is required to reduce the ripple effects and attain the potential 2 nsec switching speed offered by the GaAs FETs.

Zero-static power radio-frequency switches based on MoS2 atomristors.

PubMed

Kim, Myungsoo; Ge, Ruijing; Wu, Xiaohan; Lan, Xing; Tice, Jesse; Lee, Jack C; Akinwande, Deji

2018-06-28

Recently, non-volatile resistance switching or memristor (equivalently, atomristor in atomic layers) effect was discovered in transitional metal dichalcogenides (TMD) vertical devices. Owing to the monolayer-thin transport and high crystalline quality, ON-state resistances below 10 Ω are achievable, making MoS 2 atomristors suitable as energy-efficient radio-frequency (RF) switches. MoS 2 RF switches afford zero-hold voltage, hence, zero-static power dissipation, overcoming the limitation of transistor and mechanical switches. Furthermore, MoS 2 switches are fully electronic and can be integrated on arbitrary substrates unlike phase-change RF switches. High-frequency results reveal that a key figure of merit, the cutoff frequency (f c ), is about 10 THz for sub-μm 2 switches with favorable scaling that can afford f c above 100 THz for nanoscale devices, exceeding the performance of contemporary switches that suffer from an area-invariant scaling. These results indicate a new electronic application of TMDs as non-volatile switches for communication platforms, including mobile systems, low-power internet-of-things, and THz beam steering.

The effect of response modality on immediate serial recall in dementia of the Alzheimer type.

PubMed

Macé, Anne-Laure; Ergis, Anne-Marie; Caza, Nicole

2012-09-01

Contrary to traditional models of verbal short-term memory (STM), psycholinguistic accounts assume that temporary retention of verbal materials is an intrinsic property of word processing. Therefore, memory performance will depend on the nature of the STM tasks, which vary according to the linguistic representations they engage. The aim of this study was to explore the effect of response modality on verbal STM performance in individuals with dementia of the Alzheimer Type (DAT), and its relationship with the patients' word-processing deficits. Twenty individuals with mild DAT and 20 controls were tested on an immediate serial recall (ISR) task using the same items across two response modalities (oral and picture pointing) and completed a detailed language assessment. When scoring of ISR performance was based on item memory regardless of item order, a response modality effect was found for all participants, indicating that they recalled more items with picture pointing than with oral response. However, this effect was less marked in patients than in controls, resulting in an interaction. Interestingly, when recall of both item and order was considered, results indicated similar performance between response modalities in controls, whereas performance was worse for pointing than for oral response in patients. Picture-naming performance was also reduced in patients relative to controls. However, in the word-to-picture matching task, a similar pattern of responses was found between groups for incorrectly named pictures of the same items. The finding of a response modality effect in item memory for all participants is compatible with the assumption that semantic influences are greater in picture pointing than in oral response, as predicted by psycholinguistic models. Furthermore, patients' performance was modulated by their word-processing deficits, showing a reduced advantage relative to controls. Overall, the response modality effect observed in this study for item memory suggests that verbal STM performance is intrinsically linked with word processing capacities in both healthy controls and individuals with mild DAT, supporting psycholinguistic models of STM.

Beam-Switch Transient Effects in the RF Path of the ICAPA Receive Phased Array Antenna

NASA Technical Reports Server (NTRS)

Sands, O. Scott

2003-01-01

When the beam of a Phased Array Antenna (PAA) is switched from one pointing direction to another, transient effects in the RF path of the antenna are observed. Testing described in the report has revealed implementation-specific transient effects in the RF channel that are associated with digital clocking pulses that occur with transfer of data from the Beam Steering Controller (BSC) to the digital electronics of the PAA under test. The testing described here provides an initial assessment of the beam-switch phenomena by digitally acquiring time series of the RF communications channel, under CW excitation, during the period of time that the beam switch transient occurs. Effects are analyzed using time-frequency distributions and instantaneous frequency estimation techniques. The results of tests conducted with CW excitation supports further Bit-Error-Rate (BER) testing of the PAA communication channel.

Body-Cooling Paradigm in Sport: Maximizing Safety and Performance During Competition.

PubMed

Adams, William M; Hosokawa, Yuri; Casa, Douglas J

2016-12-01

Although body cooling has both performance and safety benefits, knowledge on optimizing cooling during specific sport competition is limited. To identify when, during sport competition, it is optimal for body cooling and to identify optimal body-cooling modalities to enhance safety and maximize sport performance. A comprehensive literature search was conducted to identify articles with specific context regarding body cooling, sport performance, and cooling modalities used during sport competition. A search of scientific peer-reviewed literature examining the effects of body cooling on exercise performance was done to examine the influence of body cooling on exercise performance. Subsequently, a literature search was done to identify effective cooling modalities that have been shown to improve exercise performance. The cooling modalities that are most effective in cooling the body during sport competition depend on the sport, timing of cooling, and feasibility based on the constraints of the sports rules and regulations. Factoring in the length of breaks (halftime substitutions, etc), the equipment worn during competition, and the cooling modalities that offer the greatest potential to cool must be considered in each individual sport. Scientific evidence supports using body cooling as a method of improving performance during sport competition. Developing a strategy to use cooling modalities that are scientifically evidence-based to improve performance while maximizing athlete's safety warrants further investigation.

Estimating multivariate similarity between neuroimaging datasets with sparse canonical correlation analysis: an application to perfusion imaging.

PubMed

Rosa, Maria J; Mehta, Mitul A; Pich, Emilio M; Risterucci, Celine; Zelaya, Fernando; Reinders, Antje A T S; Williams, Steve C R; Dazzan, Paola; Doyle, Orla M; Marquand, Andre F

2015-01-01

An increasing number of neuroimaging studies are based on either combining more than one data modality (inter-modal) or combining more than one measurement from the same modality (intra-modal). To date, most intra-modal studies using multivariate statistics have focused on differences between datasets, for instance relying on classifiers to differentiate between effects in the data. However, to fully characterize these effects, multivariate methods able to measure similarities between datasets are needed. One classical technique for estimating the relationship between two datasets is canonical correlation analysis (CCA). However, in the context of high-dimensional data the application of CCA is extremely challenging. A recent extension of CCA, sparse CCA (SCCA), overcomes this limitation, by regularizing the model parameters while yielding a sparse solution. In this work, we modify SCCA with the aim of facilitating its application to high-dimensional neuroimaging data and finding meaningful multivariate image-to-image correspondences in intra-modal studies. In particular, we show how the optimal subset of variables can be estimated independently and we look at the information encoded in more than one set of SCCA transformations. We illustrate our framework using Arterial Spin Labeling data to investigate multivariate similarities between the effects of two antipsychotic drugs on cerebral blood flow.

The Role of Working Memory Capacity and Interference Resolution Mechanisms in Task Switching

PubMed Central

Pettigrew, Corinne; Martin, Randi C.

2015-01-01

Theories of task switching have emphasized a number of control mechanisms that may support the ability to flexibly switch between tasks. The present study examined the extent to which individual differences in working memory (WM) capacity and two measures of interference resolution, response-distractor inhibition and resistance to proactive interference (PI), account for variability in task switching, including global costs, local costs, and N-2 repetition costs. 102 young and 60 older adults were tested on a battery of tasks. Composite scores were created for WM capacity, response-distractor inhibition, and resistance to PI; shifting was indexed by rate residual scores which combine response time and accuracy and account for individual differences in processing speed. Composite scores served as predictors of task switching. WM was significantly related to global switch costs. While resistance to PI and WM explained some variance in local costs, these effects did not reach significance. In contrast, none of the control measures explained variance in N-2 repetition costs. Furthermore, age effects were only evident for N-2 repetition costs, with older adults demonstrating larger costs than young adults. Results are discussed within the context of theoretical models of task switching. PMID:26594895

The role of working memory capacity and interference resolution mechanisms in task switching.

PubMed

Pettigrew, Corinne; Martin, Randi C

2016-12-01

Theories of task switching have emphasized a number of control mechanisms that may support the ability to flexibly switch between tasks. The present study examined the extent to which individual differences in working memory (WM) capacity and two measures of interference resolution, response-distractor inhibition and resistance to proactive interference (PI), account for variability in task switching, including global costs, local costs, and N-2 repetition costs. A total of 102 young and 60 older adults were tested on a battery of tasks. Composite scores were created for WM capacity, response-distractor inhibition, and resistance to PI; shifting was indexed by rate residual scores, which combine response time and accuracy and account for individual differences in processing speed. Composite scores served as predictors of task switching. WM was significantly related to global switch costs. While resistance to PI and WM explained some variance in local costs, these effects did not reach significance. In contrast, none of the control measures explained variance in N-2 repetition costs. Furthermore, age effects were only evident for N-2 repetition costs, with older adults demonstrating larger costs than young adults. Results are discussed within the context of theoretical models of task switching.

Investigation of Structures of Microwave Microelectromechanical-System Switches by Taguchi Method

NASA Astrophysics Data System (ADS)

Lai, Yeong-Lin; Lin, Chien-Hung

2007-10-01

The optimal design of microwave microelectromechanical-system (MEMS) switches by the Taguchi method is presented. The structures of the switches are analyzed and optimized in terms of the effective stiffness constant, the maximum von Mises stress, and the natural frequency in order to improve the reliability and the performance of the MEMS switches. There are four factors, each of which has three levels in the Taguchi method for the MEMS switches. An L9(34) orthogonal array is used for the matrix experiments. The characteristics of the experiments are studied by the finite-element method and the analytical method. The responses of the signal-to-noise (S/N) ratios of the characteristics of the switches are investigated. The statistical analysis of variance (ANOVA) is used to interpret the experimental results and decide the significant factors. The final optimum setting, A1B3C1D2, predicts that the effective stiffness constant is 1.06 N/m, the maximum von Mises stress is 76.9 MPa, and the natural frequency is 29.331 kHz. The corresponding switching time is 34 μs, and the pull-down voltage is 9.8 V.

Evolutionary prisoner's dilemma games on the network with punishment and opportunistic partner switching

NASA Astrophysics Data System (ADS)

Takesue, H.

2018-02-01

Punishment and partner switching are two well-studied mechanisms that support the evolution of cooperation. Observation of human behaviour suggests that the extent to which punishment is adopted depends on the usage of alternative mechanisms, including partner switching. In this study, we investigate the combined effect of punishment and partner switching in evolutionary prisoner's dilemma games conducted on a network. In the model, agents are located on the network and participate in the prisoner's dilemma games with punishment. In addition, they can opportunistically switch interaction partners to improve their payoff. Our Monte Carlo simulation showed that a large frequency of punishers is required to suppress defectors when the frequency of partner switching is low. In contrast, cooperation is the most abundant strategy when the frequency of partner switching is high regardless of the strength of punishment. Interestingly, cooperators become abundant not because they avoid the cost of inflicting punishment and earn a larger average payoff per game but rather because they have more numerous opportunities to be referred to as a role agent by defectors. Our results imply that the fluidity of social relationships has a profound effect on the adopted strategy in maintaining cooperation.

Correlated noise-based switches and stochastic resonance in a bistable genetic regulation system

NASA Astrophysics Data System (ADS)

Wang, Can-Jun; Yang, Ke-Li

2016-07-01

The correlated noise-based switches and stochastic resonance are investigated in a bistable single gene switching system driven by an additive noise (environmental fluctuations), a multiplicative noise (fluctuations of the degradation rate). The correlation between the two noise sources originates from on the lysis-lysogeny pathway system of the λ phage. The steady state probability distribution is obtained by solving the time-independent Fokker-Planck equation, and the effects of noises are analyzed. The effects of noises on the switching time between the two stable states (mean first passage time) is investigated by the numerical simulation. The stochastic resonance phenomenon is analyzed by the power amplification factor. The results show that the multiplicative noise can induce the switching from "on" → "off" of the protein production, while the additive noise and the correlation between the noise sources can induce the inverse switching "off" → "on". A nonmonotonic behaviour of the average switching time versus the multiplicative noise intensity, for different cross-correlation and additive noise intensities, is observed in the genetic system. There exist optimal values of the additive noise, multiplicative noise and cross-correlation intensities for which the weak signal can be optimal amplified.

Characterizing switching and congruency effects in the Implicit Association Test as reactive and proactive cognitive control.

PubMed

Hilgard, Joseph; Bartholow, Bruce D; Dickter, Cheryl L; Blanton, Hart

2015-03-01

Recent research has identified an important role for task switching, a cognitive control process often associated with executive functioning, in the Implicit Association Test (IAT). However, switching does not fully account for IAT effects, particularly when performance is scored using more recent d-score formulations. The current study sought to characterize multiple control processes involved in IAT performance through the use of event-related brain potentials (ERPs). Participants performed a race-evaluative IAT while ERPs were recorded. Behaviorally, participants experienced superadditive reaction time costs of incongruency and task switching, consistent with previous studies. The ERP showed a marked medial frontal negativity (MFN) 250-450 ms post-stimulus at midline fronto-central locations that were more negative for incongruent than congruent trials but more positive for switch than for no-switch trials, suggesting separable control processes are engaged by these two factors. Greater behavioral IAT bias was associated with both greater switch-related and congruency-related ERP activity. Findings are discussed in terms of the Dual Mechanisms of Control model of reactive and proactive cognitive control. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

Auditory peripersonal space in humans.

PubMed

Farnè, Alessandro; Làdavas, Elisabetta

2002-10-01

In the present study we report neuropsychological evidence of the existence of an auditory peripersonal space representation around the head in humans and its characteristics. In a group of right brain-damaged patients with tactile extinction, we found that a sound delivered near the ipsilesional side of the head (20 cm) strongly extinguished a tactile stimulus delivered to the contralesional side of the head (cross-modal auditory-tactile extinction). By contrast, when an auditory stimulus was presented far from the head (70 cm), cross-modal extinction was dramatically reduced. This spatially specific cross-modal extinction was most consistently found (i.e., both in the front and back spaces) when a complex sound was presented, like a white noise burst. Pure tones produced spatially specific cross-modal extinction when presented in the back space, but not in the front space. In addition, the most severe cross-modal extinction emerged when sounds came from behind the head, thus showing that the back space is more sensitive than the front space to the sensory interaction of auditory-tactile inputs. Finally, when cross-modal effects were investigated by reversing the spatial arrangement of cross-modal stimuli (i.e., touch on the right and sound on the left), we found that an ipsilesional tactile stimulus, although inducing a small amount of cross-modal tactile-auditory extinction, did not produce any spatial-specific effect. Therefore, the selective aspects of cross-modal interaction found near the head cannot be explained by a competition between a damaged left spatial representation and an intact right spatial representation. Thus, consistent with neurophysiological evidence from monkeys, our findings strongly support the existence, in humans, of an integrated cross-modal system coding auditory and tactile stimuli near the body, that is, in the peripersonal space.

Modal space three-state feedback control for electro-hydraulic servo plane redundant driving mechanism with eccentric load decoupling.

PubMed

Zhao, Jinsong; Wang, Zhipeng; Zhang, Chuanbi; Yang, Chifu; Bai, Wenjie; Zhao, Zining

2018-06-01

The shaking table based on electro-hydraulic servo parallel mechanism has the advantage of strong carrying capacity. However, the strong coupling caused by the eccentric load not only affects the degree of freedom space control precision, but also brings trouble to the system control. A novel decoupling control strategy is proposed, which is based on modal space to solve the coupling problem for parallel mechanism with eccentric load. The phenomenon of strong dynamic coupling among degree of freedom space is described by experiments, and its influence on control design is discussed. Considering the particularity of plane motion, the dynamic model is built by Lagrangian method to avoid complex calculations. The dynamic equations of the coupling physical space are transformed into the dynamic equations of the decoupling modal space by using the weighted orthogonality of the modal main mode with respect to mass matrix and stiffness matrix. In the modal space, the adjustments of the modal channels are independent of each other. Moreover, the paper discusses identical closed-loop dynamic characteristics of modal channels, which will realize decoupling for degree of freedom space, thus a modal space three-state feedback control is proposed to expand the frequency bandwidth of each modal channel for ensuring their near-identical responses in a larger frequency range. Experimental results show that the concept of modal space three-state feedback control proposed in this paper can effectively reduce the strong coupling problem of degree of freedom space channels, which verify the effectiveness of the proposed model space state feedback control strategy for improving the control performance of the electro-hydraulic servo plane redundant driving mechanism. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

When deception becomes easy: the effects of task switching and goal neglect on the truth proportion effect

PubMed Central

Van Bockstaele, Bram; Wilhelm, Christine; Meijer, Ewout; Debey, Evelyne; Verschuere, Bruno

2015-01-01

Lying is typically more cognitively demanding than truth telling. Yet, recent cognitive models of lying propose that lying can be just as easy as truth telling, depending on contextual factors. In line with this idea, research has shown that the cognitive cost of deception decreases when people frequently respond deceptively, while it increases when people rarely respond deceptively (i.e., the truth proportion effect). In the present study, we investigated two possible underlying mechanisms of the truth proportion effect. In Experiment 1 (N = 121), we controlled for the impact of switch costs by keeping the number of switches between deceptive and truthful responses constant. We found that people who often responded deceptively made fewer errors when responding deceptively than people who only occasionally responded deceptively, replicating the truth proportion effect. Thus, while the truth proportion effect in earlier studies may be partially driven by the cost of switching between truthful and deceptive responses, we still found evidence for the truth proportion effect while controlling for switch costs. In Experiment 2 (N = 68), we assessed whether the truth proportion effect is influenced by goal neglect. According to this view, the truth proportion effect should be reduced if participants are cued to maintain the task goals, while it should be larger when participants are allowed to neglect the task goals. In line with this hypothesis, we found a smaller truth proportion effect when participants were cued with the task goals compared to when they were not cued. This study shows that the truth proportion effect is influenced by goal neglect, implying that frequent deceptive responding strengthens the goal of responding deceptively. Our findings imply that the accuracy of lie detection tests could be increased by using a majority of truth-items (i.e., induce the truth proportion effect), and that the truth proportion effect should be maximized by (1) increasing the number of truth-lie task switches and (2) inducing goal neglect. PMID:26579047

Perceptual and Conceptual Priming of Cue Encoding in Task Switching

ERIC Educational Resources Information Center

Schneider, Darryl W.

2016-01-01

Transition effects in task-cuing experiments can be partitioned into task switching and cue repetition effects by using multiple cues per task. In the present study, the author shows that cue repetition effects can be partitioned into perceptual and conceptual priming effects. In 2 experiments, letters or numbers in their uppercase/lowercase or…

Message Modality and Source Credibility Can Interact to Affect Argument Processing.

ERIC Educational Resources Information Center

Booth-Butterfield, Steve; Gutowski, Christine

1993-01-01

Extends previous modality and source cue studies by manipulating argument quality. Randomly assigned college students by class to an argument quality by source attribute by modality factorial experiment. Finds the print mode produces only argument main effects, and audio and video modes produce argument by cue interactions. Finds data inconsistent…

The Effect of Hierarchical Task Representations on Task Selection in Voluntary Task Switching

ERIC Educational Resources Information Center

Weaver, Starla M.; Arrington, Catherine M.

2013-01-01

The current study explored the potential for hierarchical representations to influence action selection during voluntary task switching. Participants switched between 4 individual task elements. In Experiment 1, participants were encouraged to represent the task elements as grouped within a hierarchy based on experimental manipulations of varying…

47 CFR 36.125 - Local switching equipment-Category 3.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 2 2014-10-01 2014-10-01 false Local switching equipment-Category 3. 36.125... access lines, special access lines or private lines. (h) Effective July 1, 2001, through June 30, 2017..., 2017, all study areas shall apportion costs in Category 3, Local Switching Equipment, among the...

Switch Rates During Acute Treatment for Bipolar II Depression With Lithium, Sertraline, or the Two Combined: A Randomized Double-Blind Comparison.

PubMed

Altshuler, Lori L; Sugar, Catherine A; McElroy, Susan L; Calimlim, Brian; Gitlin, Michael; Keck, Paul E; Aquino-Elias, Ana; Martens, Brian E; Fischer, E Grace; English, Teri L; Roach, Janine; Suppes, Trisha

2017-03-01

The authors compared medication-induced mood switch risk (primary outcome), as well as treatment response and side effects (secondary outcomes) with three acute-phase treatments for bipolar II depression. In a 16-week, double-blind, multisite comparison study, 142 participants with bipolar II depression were randomly assigned to receive lithium monotherapy (N=49), sertraline monotherapy (N=45), or combination treatment with lithium and sertraline (N=48). At each visit, mood was assessed using standardized rating scales. Rates of switch were compared, as were rates of treatment response and the presence and severity of treatment-emergent side effects. Twenty participants (14%) experienced a switch during the study period (hypomania, N=17; severe hypomania, N=3). Switch rates did not differ among the three treatment groups, even after accounting for dropout. No patient had a manic switch or was hospitalized for a switch. Most switches occurred within the first 5 weeks of treatment. The treatment response rate for the overall sample was 62.7% (N=89), without significant differences between groups after accounting for dropout. The lithium/sertraline combination group had a significantly higher overall dropout rate than the monotherapy groups but did not have an accelerated time to response. Lithium monotherapy, sertraline monotherapy, and lithium/sertraline combination therapy were associated with similar switch and treatment response rates in participants with bipolar II depression. The dropout rate was higher in the lithium/sertraline combination treatment group, without any treatment acceleration advantage.

Antipsychotic switching for people with schizophrenia who have neuroleptic-induced weight or metabolic problems.

PubMed

Mukundan, Anitha; Faulkner, Guy; Cohn, Tony; Remington, Gary

2010-12-08

Weight gain is common for people with schizophrenia and this has serious implications for a patient's health and well being. Switching strategies have been recommended as a management option. To determine the effects of antipsychotic medication switching as a strategy for reducing or preventing weight gain and metabolic problems in people with schizophrenia. We searched key databases and the Cochrane Schizophrenia Group's trials register (January 2005 and June 2007), reference sections within relevant papers and contacted the first author of each relevant study and other experts to collect further information. All clinical randomised controlled trials comparing switching of antipsychotic medication as an intervention for antipsychotic induced weight gain and metabolic problems with continuation of medication and/or other weight loss treatments (pharmacological and non pharmacological) in people with schizophrenia or schizophrenia-like illnesses. Studies were reliably selected, quality assessed and data extracted. For dichotomous data we calculated risk ratio (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis, based on a fixed-effect model. The primary outcome measures were weight loss, metabolic syndrome, relapse and general mental state. We included four studies for the review with a total of 636 participants. All except one study had a duration of 26 weeks or less. There was a mean weight loss of 1.94 kg (2 RCT, n = 287, CI -3.9 to 0.08) when switched to aripiprazole or quetiapine from olanzapine. BMI also decreased when switched to quetiapine (1 RCT, n = 129, MD -0.52 CI -1.26 to 0.22) and aripiprazole (1 RCT, n = 173, RR 0.28 CI 0.13 to 0.57) from olanzapine.Fasting blood glucose showed a significant decrease when switched to aripiprazole or quetiapine from olanzapine. (2 RCT, MD -2.53 n = 280 CI -2.94 to -2.11). One RCT also showed a favourable lipid profile when switched to aripiprazole but these measures were reported as percentage changes, rather than means with standard deviation.People are less likely to leave the study early if they remain on olanzapine compared to switching to quetiapine or aripiprazole.There was no significant difference in outcomes of mental state, global state, and adverse events between groups which switched medications and those that remained on previous medication. Three different switching strategies were compared and no strategy was found to be superior to the others for outcomes of weight gain, mental state and global state. Evidence from this review suggests that switching antipsychotic medication to one with lesser potential for causing weight gain or metabolic problems could be an effective way to manage these side effects, but the data were weak due to the limited number of trials in this area and small sample sizes. Poor reporting of data also hindered using some trials and outcomes. There was no difference in mental state, global state and other treatment related adverse events between switching to another medication and continuing on the previous one. When the three switching strategies were compared none of them had an advantage over the others in their effects on the primary outcomes considered in this review. Better designed trials with adequate power would provide more convincing evidence for using medication switching as an intervention strategy.

Effectiveness of three just-in-time training modalities for N-95 mask fit testing.

PubMed

Jones, David; Stoler, Genevieve; Suyama, Joe

2013-01-01

To compare and contrast three different training modalities for fit testing N-95 respirator face masks. Block randomized interventional study. Urban university. Two hundred eighty-nine medical students. Students were randomly assigned to video, lecture, or slide show to evaluate the effectiveness of the methods for fit testing large groups of people. Ease of fit and success of fit for each instructional technique. Mask 1 was a Kimberly-Clark duckbill N-95 respirator mask, and mask 2 was a 3M™ carpenters N-95 respirator mask. "Ease of fit" was defined as the ability to successfully don a mask in less than 30 seconds. "Success of fit" was defined as the ability to correctly don a mask in one try. There were no statistical differences by training modality for either mask regarding ease of fit or success of fit. There were no differences among video presentation, small group demonstration, and self-directed slide show just-in-time training modalities for ease of fit or success of fit N-95 respirator mask fitting. Further study is needed to explore more effective fit training modalities.

The therapeutic effectiveness of using visual art modalities with the bereaved: a systematic review.

PubMed

Weiskittle, Rachel E; Gramling, Sandra E

2018-01-01

Bereaved individuals are increasingly considered at risk for negative psychological and physiological outcomes. Visual art modalities are often incorporated into grief therapy interventions, and clinical application of art therapy techniques with the bereaved has been widely documented. Although clinicians and recipients of these interventions advocate for their helpfulness in adapting to bereavement, research investigating the efficacy of visual art modalities has produced equivocal results and has not yet been synthesized to establish empirical support across settings. Accordingly, this review critically evaluates the existent literature on the effectiveness of visual art modalities with the bereaved and offers suggestions for future avenues of research. A total of 27 studies were included in the current review. Meta-analysis was not possible because of clinical heterogeneity and insufficient comparable data on outcome measures across studies. A narrative synthesis reports that therapeutic application of visual art modalities was associated with positive changes such as continuing bonds with the deceased and meaning making. Modest and conflicting preliminary evidence was found to support treatment effectiveness in alleviating negative grief symptoms such as general distress, functional impairment, and symptoms of depression and anxiety.

A matter of attention: Crossmodal congruence enhances and impairs performance in a novel trimodal matching paradigm.

PubMed

Misselhorn, Jonas; Daume, Jonathan; Engel, Andreas K; Friese, Uwe

2016-07-29

A novel crossmodal matching paradigm including vision, audition, and somatosensation was developed in order to investigate the interaction between attention and crossmodal congruence in multisensory integration. To that end, all three modalities were stimulated concurrently while a bimodal focus was defined blockwise. Congruence between stimulus intensity changes in the attended modalities had to be evaluated. We found that crossmodal congruence improved performance if both, the attended modalities and the task-irrelevant distractor were congruent. If the attended modalities were incongruent, the distractor impaired performance due to its congruence relation to one of the attended modalities. Between attentional conditions, magnitudes of crossmodal enhancement or impairment differed. Largest crossmodal effects were seen in visual-tactile matching, intermediate effects for audio-visual and smallest effects for audio-tactile matching. We conclude that differences in crossmodal matching likely reflect characteristics of multisensory neural network architecture. We discuss our results with respect to the timing of perceptual processing and state hypotheses for future physiological studies. Finally, etiological questions are addressed. Copyright © 2016 Elsevier Ltd. All rights reserved.

A sharp image or a sharp knife: norms for the modality-exclusivity of 774 concept-property items.

PubMed

van Dantzig, Saskia; Cowell, Rosemary A; Zeelenberg, René; Pecher, Diane

2011-03-01

According to recent embodied cognition theories, mental concepts are represented by modality-specific sensory-motor systems. Much of the evidence for modality-specificity in conceptual processing comes from the property-verification task. When applying this and other tasks, it is important to select items based on their modality-exclusivity. We collected modality ratings for a set of 387 properties, each of which was paired with two different concepts, yielding a total of 774 concept-property items. For each item, participants rated the degree to which the property could be experienced through five perceptual modalities (vision, audition, touch, smell, and taste). Based on these ratings, we computed a measure of modality exclusivity, the degree to which a property is perceived exclusively through one sensory modality. In this paper, we briefly sketch the theoretical background of conceptual knowledge, discuss the use of the property-verification task in cognitive research, provide our norms and statistics, and validate the norms in a memory experiment. We conclude that our norms are important for researchers studying modality-specific effects in conceptual processing.

Improved resistive switching characteristics of a Pt/HfO2/Pt resistor by controlling anode interface with forming and switching polarity

NASA Astrophysics Data System (ADS)

Jung, Yong Chan; Seong, Sejong; Lee, Taehoon; Kim, Seon Yong; Park, In-Sung; Ahn, Jinho

2018-03-01

The anode interface effects on the resistive switching characteristics of Pt/HfO2/Pt resistors are investigated by changing the forming and switching polarity. Resistive switching properties are evaluated and compared with the polarity operation procedures, such as the reset voltage (Vr), set voltage (Vs), and current levels at low and high resistance states. When the same forming and switching voltage polarity are applied to the resistor, their switching parameters are widely distributed. However, the opposite forming and switching voltage polarity procedures enhance the uniformity of the switching parameters. In particular, the Vs distribution is strongly affected by the voltage polarity variation. A model is proposed based on cone-shaped filament formation through the insulator and the cone diameter at the anode interface to explain the improved resistive switching characteristics under opposite polarity operation. The filament cone is thinner near the anode interface during the forming process; hence, the anode is altered by the application of a switching voltage with opposite polarity to the forming voltage polarity and the converted anode interface becomes the thicker part of the cone. The more uniform and stable switching behavior is attributed to control over the formation and rupture of the cone-shaped filaments at their thicker parts.

The modal density of composite beams incorporating the effects of shear deformation and rotary inertia

NASA Astrophysics Data System (ADS)

Bachoo, Richard; Bridge, Jacqueline

2018-06-01

Engineers and designers are often faced with the task of selecting materials that minimizes structural weight whilst meeting the required strength and stiffness. In many cases fibre reinforced composites (FRCs) are the materials of choice since they possess a combination of high strength and low density. Depending on the application, composites are frequently constructed to form long slender beam-like structures or flat thin plate-like structures. Such structures when subjected to random excitation have the potential to excite higher order vibratory modes which can contribute significantly to structure-borne sound. Statistical Energy Analysis (SEA) is a framework for modeling the high frequency vibration of structures. The modal density, which is typically defined as the number of modes per unit Hertz in a frequency band, is a fundamental parameter when applying SEA. This study derives formulas for the modal density of a fibre reinforced composite beam coupled in bending and torsion. The effects of shear deformation and rotary inertia are accounted for in the formulation. The modal density is shown to be insensitive to boundary conditions. Numerical analyses were carried out to investigate the variation of modal density with fibre orientation including and excluding the effects of shear deformation and rotary inertia. It was observed that neglecting such effects leads to underestimating the mode count in a particular frequency band. In each frequency band there exists a fibre orientation for which the modal density is minimized. This angular orientation is shown to be dependent on the shear rigidity as well as the bending, torsional and coupling rigidities. The foregoing observation becomes more pronounced with increasing frequency. The paper also addresses the modal density beyond the wave-mode transition frequency where the beam supports three propagating waves.

Economic Analyses in Squamous Cell Carcinoma of the Head and Neck: A Review of the Literature From a Clinical Perspective

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

Souza, Jonas A. de, E-mail: jdesouza@medicine.bsd.uchicago.edu; Santana, Iuri A.; Castro, Gilberto de

The purpose of this review was to describe cost-effectiveness and cost analysis studies across treatment modalities for squamous cell carcinoma of the head and neck (SCCHN), while placing their results in context of the current clinical practice. We performed a literature search in PubMed for English-language studies addressing economic analyses of treatment modalities for SCCHN published from January 2000 to March 2013. We also performed an additional search for related studies published by the National Institute for Health and Clinical Excellence in the United Kingdom. Identified articles were classified into 3 clinical approaches (organ preservation, radiation therapy modalities, and chemotherapy regimens)more » and into 2 types of economic studies (cost analysis and cost-effectiveness/cost-utility studies). All cost estimates were normalized to US dollars, year 2013 values. Our search yielded 23 articles: 13 related to organ preservation approaches, 5 to radiation therapy modalities, and 5 to chemotherapy regimens. In general, studies analyzed different questions and modalities, making it difficult to reach a conclusion. Even when restricted to comparisons of modalities within the same clinical approach, studies often yielded conflicting findings. The heterogeneity across economic studies of SCCHN should be carefully understood in light of the modeling assumptions and limitations of each study and placed in context with relevant settings of clinical practices and study perspectives. Furthermore, the scarcity of comparative effectiveness and quality-of-life data poses unique challenges for conducting economic analyses for a resource-intensive disease, such as SCCHN, that requires a multimodal care. Future research is needed to better understand how to compare the costs and cost-effectiveness of different modalities for SCCHN.« less

Experimental determination of quantum-well lifetime effect on large-signal resonant tunneling diode switching time

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

Growden, Tyler A.; Berger, Paul R., E-mail: pberger@ieee.org; Brown, E. R.

An experimental determination is presented of the effect the quantum-well lifetime has on a large-signal resonant tunneling diode (RTD) switching time. Traditional vertical In{sub 0.53}Ga{sub 0.47}As/AlAs RTDs were grown, fabricated, and characterized. The switching time was measured with a high-speed oscilloscope and found to be close to the sum of the calculated RC-limited 10%–90% switching time and the quantum-well quasibound-state lifetime. This method displays experimental evidence that the two intrinsic resonant-tunneling characteristic times act independently, and that the quasibound-state lifetime then serves as a quantum-limit on the large-signal speed of RTDs.

Modal domain fiber optic sensor for closed loop vibration control of a flexible beam

NASA Technical Reports Server (NTRS)

Cox, D.; Thomas, D.; Reichard, K.; Lindner, D.; Claus, R. O.

1990-01-01

The use of a modal domain sensor in a vibration control experiment is described. An optical fiber is bonded along the length of a flexible beam. A control signal derived from the output of the modal domain sensor is used to suppress vibrations induced in the beam. A distributed effect model for the modal domain sensor is developed and combined with models of the beam and actuator dynamics to produce a system suitable for control design.

Breakthroughs in modern cancer therapy and elusive cardiotoxicity: Critical research‐practice gaps, challenges, and insights

PubMed Central

Li, Jin; Kros, Johan M

2017-01-01

Abstract To date, five cancer treatment modalities have been defined. The three traditional modalities of cancer treatment are surgery, radiotherapy, and conventional chemotherapy, and the two modern modalities include molecularly targeted therapy (the fourth modality) and immunotherapy (the fifth modality). The cardiotoxicity associated with conventional chemotherapy and radiotherapy is well known. Similar adverse cardiac events are resurging with the fourth modality. Aside from the conventional and newer targeted agents, even the most newly developed, immune‐based therapeutic modalities of anticancer treatment (the fifth modality), e.g., immune checkpoint inhibitors and chimeric antigen receptor (CAR) T‐cell therapy, have unfortunately led to potentially lethal cardiotoxicity in patients. Cardiac complications represent unresolved and potentially life‐threatening conditions in cancer survivors, while effective clinical management remains quite challenging. As a consequence, morbidity and mortality related to cardiac complications now threaten to offset some favorable benefits of modern cancer treatments in cancer‐related survival, regardless of the oncologic prognosis. This review focuses on identifying critical research‐practice gaps, addressing real‐world challenges and pinpointing real‐time insights in general terms under the context of clinical cardiotoxicity induced by the fourth and fifth modalities of cancer treatment. The information ranges from basic science to clinical management in the field of cardio‐oncology and crosses the interface between oncology and onco‐pharmacology. The complexity of the ongoing clinical problem is addressed at different levels. A better understanding of these research‐practice gaps may advance research initiatives on the development of mechanism‐based diagnoses and treatments for the effective clinical management of cardiotoxicity. PMID:28862319

Quitting activity and tobacco brand Switching: findings from the ITC-4 Country Survey

PubMed Central

Cowie, Genevieve A.; Swift, Elena; Partos, Timea; Borland, Ron

2015-01-01

Objective Among Australian smokers, to examine associations between cigarette brand switching, quitting activity and possible causal directions by lagging the relationships in different directions. Methods Current smokers from nine waves (2002 to early 2012) of the ITC-4 Country Survey Australian dataset were surveyed. Measures were brand switching, both brand family and product type (roll-your-own versus factory-made cigarettes) reported in adjacent waves, interest in quitting, recent quit attempts, and one month sustained abstinence. Results Switching at one interval was unrelated to concurrent quit interest. Quit interest predicted switching at the following interval, but the effect disappeared once subsequent quit attempts were controlled for. Recent quit attempts more strongly predicted switching at concurrent (OR 1.34, 95% CI=1.18–1.52, p<0.001) and subsequent intervals (OR 1.31, 95% CI= 1.12–1.53, p=0.001) than switching predicted quit attempts, with greater asymmetry when both types of switching were combined. One month sustained abstinence and switching were unrelated in the same interval; however after controlling for concurrent switching and excluding type switchers, sustained abstinence predicted lower chance of switching at the following interval (OR=0.66, 95% CI=0.47–0.93, p=0.016). Conclusions The asymmetry suggests brand switching does not affect subsequent quitting. Implications Brand switching does not appear to interfere with quitting. PMID:25827182

Quitting activity and tobacco brand switching: findings from the ITC-4 Country Survey.

PubMed

Cowie, Genevieve A; Swift, Elena; Partos, Timea; Borland, Ron

2015-04-01

Among Australian smokers, to examine associations between cigarette brand switching, quitting activity and possible causal directions by lagging the relationships in different directions. Current smokers from nine waves (2002 to early 2012) of the ITC-4 Country Survey Australian dataset were surveyed. Measures were brand switching, both brand family and product type (roll-your-own versus factory-made cigarettes) reported in adjacent waves, interest in quitting, recent quit attempts, and one month sustained abstinence. Switching at one interval was unrelated to concurrent quit interest. Quit interest predicted switching at the following interval, but the effect disappeared once subsequent quit attempts were controlled for. Recent quit attempts more strongly predicted switching at concurrent (OR 1.34, 95%CI=1.18-1.52, p<0.001) and subsequent intervals (OR 1.31, 95%CI=1.12-1.53, p=0.001) than switching predicted quit attempts, with greater asymmetry when both types of switching were combined. One month sustained abstinence and switching were unrelated in the same interval; however, after controlling for concurrent switching and excluding type switchers, sustained abstinence predicted lower chance of switching at the following interval (OR=0.66, 95%CI=0.47-0.93, p=0.016). The asymmetry suggests brand switching does not affect subsequent quitting. Brand switching does not appear to interfere with quitting. © 2015 Public Health Association of Australia.

Review: Electrostatically actuated nanobeam-based nanoelectromechanical switches – materials solutions and operational conditions

PubMed Central

Jasulaneca, Liga; Kosmaca, Jelena; Meija, Raimonds; Andzane, Jana

2018-01-01

This review summarizes relevant research in the field of electrostatically actuated nanobeam-based nanoelectromechanical (NEM) switches. The main switch architectures and structural elements are briefly described and compared. Investigation methods that allow for exploring coupled electromechanical interactions as well as studies of mechanically or electrically induced effects are covered. An examination of the complex nanocontact behaviour during various stages of the switching cycle is provided. The choice of the switching element and the electrode is addressed from the materials perspective, detailing the benefits and drawbacks for each. An overview of experimentally demonstrated NEM switching devices is provided, and together with their operational parameters, the reliability issues and impact of the operating environment are discussed. Finally, the most common NEM switch failure modes and the physical mechanisms behind them are reviewed and solutions proposed. PMID:29441272

QKD-Based Secured Burst Integrity Design for Optical Burst Switched Networks

NASA Astrophysics Data System (ADS)

Balamurugan, A. M.; Sivasubramanian, A.; Parvathavarthini, B.

2016-03-01

The field of optical transmission has undergone numerous advancements and is still being researched mainly due to the fact that optical data transmission can be done at enormous speeds. It is quite evident that people prefer optical communication when it comes to large amount of data involving its transmission. The concept of switching in networks has matured enormously with several researches, architecture to implement and methods starting with Optical circuit switching to Optical Burst Switching. Optical burst switching is regarded as viable solution for switching bursts over networks but has several security vulnerabilities. However, this work exploited the security issues associated with Optical Burst Switching with respect to integrity of burst. This proposed Quantum Key based Secure Hash Algorithm (QKBSHA-512) with enhanced compression function design provides better avalanche effect over the conventional integrity algorithms.

Incremental passivity and output regulation for switched nonlinear systems

NASA Astrophysics Data System (ADS)

Pang, Hongbo; Zhao, Jun

2017-10-01

This paper studies incremental passivity and global output regulation for switched nonlinear systems, whose subsystems are not required to be incrementally passive. A concept of incremental passivity for switched systems is put forward. First, a switched system is rendered incrementally passive by the design of a state-dependent switching law. Second, the feedback incremental passification is achieved by the design of a state-dependent switching law and a set of state feedback controllers. Finally, we show that once the incremental passivity for switched nonlinear systems is assured, the output regulation problem is solved by the design of global nonlinear regulator controllers comprising two components: the steady-state control and the linear output feedback stabilising controllers, even though the problem for none of subsystems is solvable. Two examples are presented to illustrate the effectiveness of the proposed approach.

Response format, magnitude of laterality effects, and sex differences in laterality.

PubMed

Voyer, Daniel; Doyle, Randi A

2012-01-01

The present study examined the evidence for the claim that response format might affect the magnitude of laterality effects by means of a meta-analysis. The analysis included the 396 effect sizes drawn from 266 studies retrieved by Voyer (1996) and relevant to the main effect of laterality and sex differences in laterality for verbal and non-verbal tasks in the auditory, tactile, and visual sensory modality. The response format used in specific studies was the only moderator variable of interest in the present analysis, resulting in four broad response categories (oral, written, computer, and pointing). A meta-analysis analogue to ANOVA showed no significant influence of response format on either the main effect of laterality or sex differences in laterality when all sensory modalities were combined. However, when modalities were considered separately, response format affected the main effect of laterality in the visual modality, with a clear advantage for written responses. Further pointed analyses revealed some specific differences among response formats. Results are discussed in terms of their implications for the measurement of laterality.

Modal noise in multimode optical fibers

NASA Astrophysics Data System (ADS)

Rawson, E. G.; Goodman, J. W.

1983-03-01

A changing speckle pattern exists at the output of a multimode optical fiber if the optical source is sufficiently coherent. When spatial filtration (for example, at a misaligned connector) or polarization filtration (for example, in certain access couplers) occurs in the presence of such speckle, the optical signal power fluctuates; such fluctuations are called 'modal noise'. This paper reviews modal noise theory and experiment, including the prediction and measurement of the modal noise signal-to-noise ratio in the presence of spatial filtration and constrained total guided power. It also presents new results relating to modal noise effects in fiber branching devices such as star couplers, access couplers, and power dividers.

Tailoring of the free spectral range and geometrical cavity dispersion of a microsphere by a coating layer.

PubMed

Ristić, Davor; Mazzola, Maurizio; Chiappini, Andrea; Rasoloniaina, Alphonse; Féron, Patrice; Ramponi, Roberta; Righini, Giancarlo C; Cibiel, Gilles; Ivanda, Mile; Ferrari, Maurizio

2014-09-01

The modal dispersion of a whispering gallery mode (WGM) resonator is a very important parameter for use in all nonlinear optics applications. In order to tailor the WGM modal dispersion of a microsphere, we have coated a silica microsphere with a high-refractive-index coating in order to study its effect on the WGM modal dispersion. We used Er(3+) ions as a probe for a modal dispersion assessment. We found that, by varying the coating thickness, the geometrical cavity dispersion can be used to shift overall modal dispersion in a very wide range in both the normal and anomalous dispersion regime.

Modal response of a computational vocal fold model with a substrate layer of adipose tissue.

PubMed

Jones, Cameron L; Achuthan, Ajit; Erath, Byron D

2015-02-01

This study demonstrates the effect of a substrate layer of adipose tissue on the modal response of the vocal folds, and hence, on the mechanics of voice production. Modal analysis is performed on the vocal fold structure with a lateral layer of adipose tissue. A finite element model is employed, and the first six mode shapes and modal frequencies are studied. The results show significant changes in modal frequencies and substantial variation in mode shapes depending on the strain rate of the adipose tissue. These findings highlight the importance of considering adipose tissue in computational vocal fold modeling.

Proton-Controlled Organic Microlaser Switch.

PubMed

Gao, Zhenhua; Zhang, Wei; Yan, Yongli; Yi, Jun; Dong, Haiyun; Wang, Kang; Yao, Jiannian; Zhao, Yong Sheng

2018-05-25

Microscale laser switches have been playing irreplaceable roles in the development of photonic devices with high integration levels. However, it remains a challenge to switch the lasing wavelengths across a wide range due to relatively fixed energy bands in traditional semiconductors. Here, we report a strategy to switch the lasing wavelengths among multiple states based on a proton-controlled intramolecular charge-transfer (ICT) process in organic dye-doped flexible microsphere resonant cavities. The protonic acids can effectively bind onto the ICT molecules, which thus enhance the ICT strength of the dyes and lead to a red-shifted gain behavior. On this basis, the gain region was effectively modulated by using acids with different proton-donating ability, and as a result, laser switching among multiple wavelengths was achieved. The results will provide guidance for the rational design of miniaturized lasers with performances based on the characteristic of organic optoelectronic materials.

Clustering promotes switching dynamics in networks of noisy neurons

NASA Astrophysics Data System (ADS)

Franović, Igor; Klinshov, Vladimir

2018-02-01

Macroscopic variability is an emergent property of neural networks, typically manifested in spontaneous switching between the episodes of elevated neuronal activity and the quiescent episodes. We investigate the conditions that facilitate switching dynamics, focusing on the interplay between the different sources of noise and heterogeneity of the network topology. We consider clustered networks of rate-based neurons subjected to external and intrinsic noise and derive an effective model where the network dynamics is described by a set of coupled second-order stochastic mean-field systems representing each of the clusters. The model provides an insight into the different contributions to effective macroscopic noise and qualitatively indicates the parameter domains where switching dynamics may occur. By analyzing the mean-field model in the thermodynamic limit, we demonstrate that clustering promotes multistability, which gives rise to switching dynamics in a considerably wider parameter region compared to the case of a non-clustered network with sparse random connection topology.

Short-term memory for event duration: modality specificity and goal dependency.

PubMed

Takahashi, Kohske; Watanabe, Katsumi

2012-11-01

Time perception is involved in various cognitive functions. This study investigated the characteristics of short-term memory for event duration by examining how the length of the retention period affects inter- and intramodal duration judgment. On each trial, a sample stimulus was followed by a comparison stimulus, after a variable delay period (0.5-5 s). The sample and comparison stimuli were presented in the visual or auditory modality. The participants determined whether the comparison stimulus was longer or shorter than the sample stimulus. The distortion pattern of subjective duration during the delay period depended on the sensory modality of the comparison stimulus but was not affected by that of the sample stimulus. When the comparison stimulus was visually presented, the retained duration of the sample stimulus was shortened as the delay period increased. Contrarily, when the comparison stimulus was presented in the auditory modality, the delay period had little to no effect on the retained duration. Furthermore, whenever the participants did not know the sensory modality of the comparison stimulus beforehand, the effect of the delay period disappeared. These results suggest that the memory process for event duration is specific to sensory modality and that its performance is determined depending on the sensory modality in which the retained duration will be used subsequently.

F45. THE EFFICACY AND SAFETY OF BLONASERIN AFTER SWITCHING FROM OTHER ATYPICAL ANTIPSYCHOTICS IN SCHIZOPHRENIC INPATIENTS: AN OPEN-LABEL, MULTI-CENTER TRIAL

PubMed Central

Yoon, Bo-Hyun; Bahk, Won-Myong; Kwon, Young Joon; Lee, Sang-Yeol; Lee, Kwanghun; Kim, Moon Doo; Park, Sung-Yong; Song, Min-Kyu

2018-01-01

Abstract Background The aim of this study was to investigate the efficacy and safety of blonanserin treatment after switching from other atypical antipsychotics in schizophrenic inpatients who showed inadequate efficacy and poor tolerability. Methods A total of 63 schizophrenic inpatients (inadequate response group=45 and poor tolerability group=18) were included in this study. They were already treated with atypical antipsychotics except blonanserin and not favored due to inadequate responses or intolerable adverse effects. Blonanserin was administered during 12 weeks after switching from their previous antispsychotics. Treatment response was evaluated with Brief Psychiatric Rating Scale (BPRS) and CGI-S, and safety profile were measured with Abnormal Involuntary Movement Scale (AIMS), Simpson-Angus Extrapyramidal Side effects Scale (SAR)S and Barnes Akathisia Rating Scale (BARS). Drug Attitude Inventory (DAI-10) and Subjective Well-being Under Neuroleptic Treatment (SWN) were used for subjective estimates. Assessments were done at baseline, 1, 2, 4, 8 and 12 weeks after blonanserin treatment. Repeated measures of ANOVA were done to analyze the group (inadequate vs. intolerable group) and time effects. Results CGI and BPRS were showed significant treatment responses after switching to Blonaserin. Time effects were significant at 2, 4, 8, 12 weeks after switching and group by time effect were also significant at that time. Mean changes of AIMS, SARS and BARS scores were not significant throughout test trial. Although SWN was significantly improved after switching to Blonaserin, it was not found significant group by time effect. Discussion The results suggest that blonanserin may be effective and well tolerable in schizophrenic patients who showed inadequate treatment response or poor tolerability.

The effect of modality and narration style on recall of online health information: results from a Web-based experiment.

PubMed

Bol, Nadine; van Weert, Julia C M; de Haes, Hanneke C J M; Loos, Eugene F; Smets, Ellen M A

2015-04-24

Older adults are increasingly using the Internet for health information; however, they are often not able to correctly recall Web-based information (eHealth information). Recall of information is crucial for optimal health outcomes, such as adequate disease management and adherence to medical regimes. Combining effective message strategies may help to improve recall of eHealth information among older adults. Presenting information in an audiovisual format using conversational narration style is expected to optimize recall of information compared to other combinations of modality and narration style. The aim of this paper is to investigate the effect of modality and narration style on recall of health information, and whether there are differences between younger and older adults. We conducted a Web-based experiment using a 2 (modality: written vs audiovisual information) by 2 (narration style: formal vs conversational style) between-subjects design (N=440). Age was assessed in the questionnaire and included as a factor: younger (<65 years) versus older (≥65 years) age. Participants were randomly assigned to one of four experimental webpages where information about lung cancer treatment was presented. A Web-based questionnaire assessed recall of eHealth information. Audiovisual modality (vs written modality) was found to increase recall of information in both younger and older adults (P=.04). Although conversational narration style (vs formal narration style) did not increase recall of information (P=.17), a synergistic effect between modality and narration style was revealed: combining audiovisual information with conversational style outperformed combining written information with formal style (P=.01), as well as written information with conversational style (P=.045). This finding suggests that conversational style especially increases recall of information when presented audiovisually. This combination of modality and narration style improved recall of information among both younger and older adults. We conclude that combining audiovisual information with conversational style is the best way to present eHealth information to younger and older adults. Even though older adults did not proportionally recall more when audiovisual information was combined with conversational style than younger adults, this study reveals interesting implications for improving eHealth information that is effective for both younger and older adults.

Facilitation of Ferroelectric Switching via Mechanical Manipulation of Hierarchical Nanoscale Domain Structures.

PubMed

Chen, Zibin; Hong, Liang; Wang, Feifei; Ringer, Simon P; Chen, Long-Qing; Luo, Haosu; Liao, Xiaozhou

2017-01-06

Heterogeneous ferroelastic transition that produces hierarchical 90° tetragonal nanodomains via mechanical loading and its effect on facilitating ferroelectric domain switching in relaxor-based ferroelectrics were explored. Combining in situ electron microscopy characterization and phase-field modeling, we reveal the nature of the transition process and discover that the transition lowers by 40% the electrical loading threshold needed for ferroelectric domain switching. Our results advance the fundamental understanding of ferroelectric domain switching behavior.

Primary prevention of cannabis use: a systematic review of randomized controlled trials.

PubMed

Norberg, Melissa M; Kezelman, Sarah; Lim-Howe, Nicholas

2013-01-01

A systematic review of primary prevention was conducted for cannabis use outcomes in youth and young adults. The aim of the review was to develop a comprehensive understanding of prevention programming by assessing universal, targeted, uni-modal, and multi-modal approaches as well as individual program characteristics. Twenty-eight articles, representing 25 unique studies, identified from eight electronic databases (EMBASE, MEDLINE, CINAHL, ERIC, PsycINFO, DRUG, EBM Reviews, and Project CORK), were eligible for inclusion. Results indicated that primary prevention programs can be effective in reducing cannabis use in youth populations, with statistically significant effect sizes ranging from trivial (0.07) to extremely large (5.26), with the majority of significant effect sizes being trivial to small. Given that the preponderance of significant effect sizes were trivial to small and that percentages of statistically significant and non-statistically significant findings were often equivalent across program type and individual components, the effectiveness of primary prevention for cannabis use should be interpreted with caution. Universal multi-modal programs appeared to outperform other program types (i.e, universal uni-modal, targeted multi-modal, targeted unimodal). Specifically, universal multi-modal programs that targeted early adolescents (10-13 year olds), utilised non-teacher or multiple facilitators, were short in duration (10 sessions or less), and implemented boosters sessions were associated with large median effect sizes. While there were studies in these areas that contradicted these results, the results highlight the importance of assessing the interdependent relationship of program components and program types. Finally, results indicated that the overall quality of included studies was poor, with an average quality rating of 4.64 out of 9. Thus, further quality research and reporting and the development of new innovative programs are required.

Primary Prevention of Cannabis Use: A Systematic Review of Randomized Controlled Trials

PubMed Central

Norberg, Melissa M.; Kezelman, Sarah; Lim-Howe, Nicholas

2013-01-01

A systematic review of primary prevention was conducted for cannabis use outcomes in youth and young adults. The aim of the review was to develop a comprehensive understanding of prevention programming by assessing universal, targeted, uni-modal, and multi-modal approaches as well as individual program characteristics. Twenty-eight articles, representing 25 unique studies, identified from eight electronic databases (EMBASE, MEDLINE, CINAHL, ERIC, PsycINFO, DRUG, EBM Reviews, and Project CORK), were eligible for inclusion. Results indicated that primary prevention programs can be effective in reducing cannabis use in youth populations, with statistically significant effect sizes ranging from trivial (0.07) to extremely large (5.26), with the majority of significant effect sizes being trivial to small. Given that the preponderance of significant effect sizes were trivial to small and that percentages of statistically significant and non-statistically significant findings were often equivalent across program type and individual components, the effectiveness of primary prevention for cannabis use should be interpreted with caution. Universal multi-modal programs appeared to outperform other program types (i.e, universal uni-modal, targeted multi-modal, targeted unimodal). Specifically, universal multi-modal programs that targeted early adolescents (10–13 year olds), utilised non-teacher or multiple facilitators, were short in duration (10 sessions or less), and implemented boosters sessions were associated with large median effect sizes. While there were studies in these areas that contradicted these results, the results highlight the importance of assessing the interdependent relationship of program components and program types. Finally, results indicated that the overall quality of included studies was poor, with an average quality rating of 4.64 out of 9. Thus, further quality research and reporting and the development of new innovative programs are required. PMID:23326396

Comparison of two Q-switched lasers and a short-pulse erbium-doped yttrium aluminum garnet laser for treatment of cosmetic tattoos containing titanium and iron in an animal model.

PubMed

Wang, Chia-Chen; Huang, Chuen-Lin; Yang, An-Hang; Chen, Chih-Kang; Lee, Shao-Chen; Leu, Fur-Jiang

2010-11-01

Cosmetic tattoos contain titanium and ferric oxide and darken through reduction after Q-switched laser irradiation. The optimal treatment for removing these pigments remains unknown. To compare the effects of two Q-switched lasers and a short-pulse erbium-doped yttrium aluminum garnet (SP Er:YAG) laser to remove cosmetic tattoos in an animal model. Rats were tattooed using white, flesh-colored, and brown inks (4 bands of each color) on their backs. For each color, one band was left untreated, and one each was treated with a Q-switched neodymium-doped YAG laser, a Q-switched alexandrite laser, and a SP Er:YAG laser every 3 weeks until the pigments were clear. The two Q-switched lasers were equally effective; all three pigments darkened initially and then resolved gradually. Up to 20, 18, and 10 sessions were required to remove white, flesh-colored, and brown tattoos, respectively. Only six sessions were required with the SP Er:YAG laser. Minimal scarring was observed with all lasers. Skin biopsies confirmed pigment granule fragmentation after Q-switched laser treatment and a decrease in the amount of pigment after SP Er:YAG laser treatment. The SP Er:YAG laser was superior to the Q-switched lasers for removing cosmetic tattoos. © 2010 by the American Society for Dermatologic Surgery, Inc.

Modeling of thermal coupling in VO2-based oscillatory neural networks

NASA Astrophysics Data System (ADS)

Velichko, Andrey; Belyaev, Maksim; Putrolaynen, Vadim; Perminov, Valentin; Pergament, Alexander

2018-01-01

In this study, we have demonstrated the possibility of using the thermal coupling to control the dynamics of operation of coupled VO2 oscillators. Based on the example of a 'switch-microheater' pair, we have explored the synchronization and dissynchronization modes of a single oscillator with respect to an external harmonic heat impact. The features of changes in the spectra are shown, in particular, the effect of the natural frequency attraction to the affecting signal frequency and the self-oscillation noise reduction effects at synchronization. The time constant of the temperature effect for the considered system configuration is in the range 7-140 μs, which allows operation in the oscillation frequency range of up to ∼70 kHz. A model estimate of the minimum temperature sensitivity of the switch is δTswitch ∼ 0.2 K, and the effective action radius RTC of the switch-to-switch thermal coupling is not less than 25 μm. Nevertheless, as the simulation shows, the frequency range can be significantly extended up to the values of 1-30 GHz if using nanometer-scale switches (heaters).

Superior bit error rate and jitter due to improved switching field distribution in exchange spring magnetic recording media

PubMed Central

Suess, D.; Fuger, M.; Abert, C.; Bruckner, F.; Vogler, C.

2016-01-01

We report two effects that lead to a significant reduction of the switching field distribution in exchange spring media. The first effect relies on a subtle mechanism of the interplay between exchange coupling between soft and hard layers and anisotropy that allows significant reduction of the switching field distribution in exchange spring media. This effect reduces the switching field distribution by about 30% compared to single-phase media. A second effect is that due to the improved thermal stability of exchange spring media over single-phase media, the jitter due to thermal fluctuation is significantly smaller for exchange spring media than for single-phase media. The influence of this overall improved switching field distribution on the transition jitter in granular recording and the bit error rate in bit-patterned magnetic recording is discussed. The transition jitter in granular recording for a distribution of Khard values of 3% in the hard layer, taking into account thermal fluctuations during recording, is estimated to be a = 0.78 nm, which is similar to the best reported calculated jitter in optimized heat-assisted recording media. PMID:27245287

Out with the Old and in with the New—Is Backward Inhibition a Domain-Specific Process?

PubMed Central

Menghini, Deny; Vicari, Stefano; Petrosini, Laura; Ferlazzo, Fabio

2015-01-01

Effective task switching is supported by the inhibition of the just executed task, so that potential interference from previously executed tasks is adaptively counteracted. This inhibitory mechanism, named Backward Inhibition (BI), has been inferred from the finding that switching back to a recently executed task (A-B-A task sequence) is harder than switching back to a less recently executed task (C-B-A task sequence). Despite the fact that BI effects do impact performance on everyday life activities, up to now it is still not clear whether the BI represents an amodal and material-independent process or whether it interacts with the task material. To address this issue, a group of individuals with Williams syndrome (WS) characterized by specific difficulties in maintaining and processing visuo-spatial, but not verbal, information, and a mental age- and gender-matched group of typically developing (TD) children were subjected to three task-switching experiments requiring verbal or visuo-spatial material to be processed. Results showed that individuals with WS exhibited a normal BI effect during verbal task-switching, but a clear deficit during visuo-spatial task-switching. Overall, our findings demonstrating that the BI is a material-specific process have important implications for theoretical models of cognitive control and its architecture. PMID:26565628

A Multicontrolled Enamine Configurational Switch Undergoing Dynamic Constitutional Exchange.

PubMed

Ren, Yansong; Svensson, Per H; Ramström, Olof

2018-05-22

A multiresponsive enamine-based molecular switch is presented, in which forward/backward configurational rotation around the C=C bond could be precisely controlled by the addition of an acid/base or metal ions. Fluorescence turn-on/off effects and large Stokes shifts were observed while regulating the switching process with Cu II . The enamine functionality furthermore enabled double dynamic regimes, in which configurational switching could operate in conjunction with constitutional enamine exchange of the rotor part. This behavior was used to construct a prototypical dynamic covalent switch system through enamine exchange with primary amines. The dynamic exchange process could be readily turned on/off by regulating the switch status with pH. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

PWM Switching Frequency Effects on Eddy Current Sensors for Magnetically Suspended Flywheel Systems

NASA Technical Reports Server (NTRS)

Jansen, Ralph; Lebron, Ramon; Dever, Timothy P.; Birchenough, Arthur G.

2003-01-01

A flywheel magnetic bearing (MB) pulse width modulated power amplifier (PWM) configuration is selected to minimize noise generated by the PWMs in the flywheel position sensor system. Two types of noise are addressed: beat frequency noise caused by variations in PWM switching frequencies, and demodulation noise caused by demodulation of high order harmonics of the switching voltage into the MB control band. Beat frequency noise is eliminated by synchronizing the PWM switch frequencies, and demodulation noise is minimized by selection of a switching frequency which does not have harmonics at the carrier frequency of the sensor. The recommended MB PWM system has five synchronized PWMs switching at a non-integer harmonic of the sensor carrier.

Chopper-stabilized phase detector

NASA Technical Reports Server (NTRS)

Hopkins, P. M.

1978-01-01

Phase-detector circuit for binary-tracking loops and other binary-data acquisition systems minimizes effects of drift, gain imbalance, and voltage offset in detector circuitry. Input signal passes simultaneously through two channels where it is mixed with early and late codes that are alternately switched between channels. Code switching is synchronized with polarity switching of detector output of each channel so that each channel uses each detector for half time. Net result is that dc offset errors are canceled, and effect of gain imbalance is simply change in sensitivity.

Proton Single Event Effects (SEE) Testing of the Myrinet Crossbar Switch and Network Interface Card

NASA Technical Reports Server (NTRS)

Howard, James W., Jr.; LaBel, Kenneth A.; Carts, Martin A.; Stattel, Ronald; Irwin, Timothy L.; Day, John H. (Technical Monitor)

2002-01-01

As part of the Remote Exploration and Experimentation Project (REE), work was performed to do a proton SEE (Single Event Effect) evaluation of the Myricom network protocol system (Myrinet). This testing included the evaluation of the Myrinet crossbar switch and the Network Interface Card (NIC). To this end, two crossbar switch devices and five components in the NIC were exposed to the proton beam at the University of California at Davis Crocker Nuclear Laboratory (CNL).

The Effects of Level of Autonomy on Human-Agent Teaming for Multi-Robot Control and Local Security Maintenance

DTIC Science & Technology

2013-11-01

different types of tasks, the associated costs of task switching also increase (Squire et al., 2006). Task switching costs may be increased with higher...switching costs as well, particularly when managing robot teams of increasing size (Squire et al., 2006). 1.3 Individual Differences The effects of...Research: Ready to Deliver the Promises. Mind 2003, 2 (3), 4. Jian, J.; Bisantz, A. M.; Drury , C. G. Foundations for an Empirically Determined Scale

Analysis of flexible aircraft longitudinal dynamics and handling qualities. Volume 2: Data

NASA Technical Reports Server (NTRS)

Waszak, M. R.; Schmidt, D. K.

1985-01-01

Two analysis methods are applied to a family of flexible aircraft in order to investigate how and when structural (especially dynamic aeroelastic) effects affect the dynamic characteristics of aircraft. The first type of analysis is an open loop modal analysis technique. This method considers the effect of modal residue magnitudes on determining vehicle handling qualities. The second method is a pilot in the loop analysis procedure that considers several closed loop system characteristics. Both analyses indicated that dynamic aeroelastic effects caused a degradation in vehicle tracking performance, based on the evaluation of some simulation results. Volume 2 consists of the presentation of the state variable models of the flexible aircraft configurations used in the analysis applications mode shape plots for the structural modes, numerical results from the modal analysis frequency response plots from the pilot in the loop analysis and a listing of the modal analysis computer program.

Resolving Task Rule Incongruence during Task Switching by Competitor Rule Suppression

ERIC Educational Resources Information Center

Meiran, Nachshon; Hsieh, Shulan; Dimov, Eduard

2010-01-01

Task switching requires maintaining readiness to execute any task of a given set of tasks. However, when tasks switch, the readiness to execute the now-irrelevant task generates interference, as seen in the task rule incongruence effect. Overcoming such interference requires fine-tuned inhibition that impairs task readiness only minimally. In an…

Cognates Facilitate Switches and Then Confusion: Contrasting Effects of Cascade versus Feedback on Language Selection

ERIC Educational Resources Information Center

Li, Chuchu; Gollan, Tamar H.

2018-01-01

The current study investigated the hypothesis that cognates (i.e., translation equivalents that overlap in form, e.g., "lemon" is "limón" in Spanish) facilitate language switches. Spanish-English bilinguals were cued to switch languages while repeatedly naming pictures with cognate versus noncognate names in separate…

All-optical switching of silicon disk resonator based on photothermal effect in metal-insulator-metal absorber.

PubMed

Shi, Yuechun; Chen, Xi; Lou, Fei; Chen, Yiting; Yan, Min; Wosinski, Lech; Qiu, Min

2014-08-01

Efficient narrowband light absorption by a metal-insulator-metal (MIM) structure can lead to high-speed light-to-heat conversion at a micro- or nanoscale. Such a MIM structure can serve as a heater for achieving all-optical light control based on the thermo-optical (TO) effect. Here we experimentally fabricated and characterized a novel all-optical switch based on a silicon microdisk integrated with a MIM light absorber. Direct integration of the absorber on top of the microdisk reduces the thermal capacity of the whole device, leading to high-speed TO switching of the microdisk resonance. The measurement result exhibits a rise time of 2.0 μs and a fall time of 2.6 μs with switching power as low as 0.5 mW; the product of switching power and response time is only about 1.3  mW·μs. Since no auxiliary elements are required for the heater, the switch is structurally compact, and its fabrication is rather easy. The device potentially can be deployed for new kinds of all-optical applications.

Conductive atomic force microscopy study of the photoexcitation effect on resistive switching in ZrO2(Y) films with Au nanoparticles

NASA Astrophysics Data System (ADS)

Novikov, A. S.; Filatov, D. O.; Antonov, D. A.; Antonov, I. N.; Shenina, M. E.; Gorshkov, O. N.

2018-03-01

We report on the experimental observation of the effect of optical excitation on resistive switching in ultrathin ZrO2(Y) films with single-layered arrays of Au nanoparticles. The samples were prepared by depositing nanometer-thick Au films sandwiched between two ZrO2(Y) layers by magnetron sputtering followed by annealing. Resistive switching was studied by conductive atomic force microscopy by measuring cyclic current-voltage curves of a probe-to-sample contact. The contact area was illuminated by radiation of a semiconductor laser diode with the wavelength corresponding to the plasmon resonance in an Au nanoparticle array. The enhancement of the hysteresis in cyclic current-voltage curves due to bipolar resistive switching under illumination was observed. The effect was attributed to heating of Au nanoparticles due to plasmonic optical absorption and a plasmon resonance, which enhances internal photoemission of electrons from the Fermi level in Au nanoparticles into the conduction band of ZrO2(Y). Both factors promote resistive switching in a ZrO2(Y) matrix.

Odors Bias Time Perception in Visual and Auditory Modalities

PubMed Central

Yue, Zhenzhu; Gao, Tianyu; Chen, Lihan; Wu, Jiashuang

2016-01-01

Previous studies have shown that emotional states alter our perception of time. However, attention, which is modulated by a number of factors, such as emotional events, also influences time perception. To exclude potential attentional effects associated with emotional events, various types of odors (inducing different levels of emotional arousal) were used to explore whether olfactory events modulated time perception differently in visual and auditory modalities. Participants were shown either a visual dot or heard a continuous tone for 1000 or 4000 ms while they were exposed to odors of jasmine, lavender, or garlic. Participants then reproduced the temporal durations of the preceding visual or auditory stimuli by pressing the spacebar twice. Their reproduced durations were compared to those in the control condition (without odor). The results showed that participants produced significantly longer time intervals in the lavender condition than in the jasmine or garlic conditions. The overall influence of odor on time perception was equivalent for both visual and auditory modalities. The analysis of the interaction effect showed that participants produced longer durations than the actual duration in the short interval condition, but they produced shorter durations in the long interval condition. The effect sizes were larger for the auditory modality than those for the visual modality. Moreover, by comparing performance across the initial and the final blocks of the experiment, we found odor adaptation effects were mainly manifested as longer reproductions for the short time interval later in the adaptation phase, and there was a larger effect size in the auditory modality. In summary, the present results indicate that odors imposed differential impacts on reproduced time durations, and they were constrained by different sensory modalities, valence of the emotional events, and target durations. Biases in time perception could be accounted for by a framework of attentional deployment between the inducers (odors) and emotionally neutral stimuli (visual dots and sound beeps). PMID:27148143

Task Uncertainty Can Account for Mixing and Switch Costs in Task-Switching

PubMed Central

Rennie, Jaime L.

2015-01-01

Cognitive control is required in situations that involve uncertainty or change, such as when resolving conflict, selecting responses and switching tasks. Recently, it has been suggested that cognitive control can be conceptualised as a mechanism which prioritises goal-relevant information to deal with uncertainty. This hypothesis has been supported using a paradigm that requires conflict resolution. In this study, we examine whether cognitive control during task switching is also consistent with this notion. We used information theory to quantify the level of uncertainty in different trial types during a cued task-switching paradigm. We test the hypothesis that differences in uncertainty between task repeat and task switch trials can account for typical behavioural effects in task-switching. Increasing uncertainty was associated with less efficient performance (i.e., slower and less accurate), particularly on switch trials and trials that afford little opportunity for advance preparation. Interestingly, both mixing and switch costs were associated with a common episodic control process. These results support the notion that cognitive control may be conceptualised as an information processor that serves to resolve uncertainty in the environment. PMID:26107646

Characteristics of silicon-based Sagnac optical switches using magneto-optical micro-ring array

NASA Astrophysics Data System (ADS)

Ni, Shuang; Wu, Baojian; Liu, Yawen

2018-01-01

The miniaturization and integration of optical switches are necessary for photonic switching networks and the utilization of magneto optical effects is a promising candidate. We propose a Sagnac optical switch chip based on the principle of nonreciprocal phase shift (NPS) of the magneto-optical (MO) micro-ring (MOMR) array, composed of SiO2/Si/Ce:YIG/SGGG. The MO switching function is realized by controlling the drive current in the snake-like metal microstrip circuit layered on the MOMRs. The transmission characteristics of the Sagnac MO switch chip dependent on magnetization intensity, waveguide coupling coefficient and waveguide loss are simulated. By optimizing the coupling coefficients, we design an MO switch using two serial MOMRs with a circumference of 38.37 μm, and the 3dB bandwidth and the extinction ratio are respectively up to 1.6 nm and 50dB for the waveguide loss coefficient of ?. And the switching magnetization can be further reduced by increasing the number of parallel MOMRs. The frequency response of the MO Sagnac switch is analyzed as well.

The other fiber, the other fabric, the other way

NASA Astrophysics Data System (ADS)

Stephens, Gary R.

1993-02-01

Coaxial cable and distributed switches provide a way to configure high-speed Fiber Channel fabrics. This type of fabric provides a cost-effective alternative to a fabric of optical fibers and centralized cross-point switches. The fabric topology is a simple tree. Products using parallel busses require a significant change to migrate to a serial bus. Coaxial cables and distributed switches require a smaller technology shift for these device manufacturers. Each distributed switch permits both medium type and speed changes. The fabric can grow and bridge to optical fibers as the needs expand. A distributed fabric permits earlier entry into high-speed serial operations. For very low-cost fabrics, a distributed switch may permit a link configured as a loop. The loop eliminates half of the ports when compared to a switched point-to-point fabric. A fabric of distributed switches can interface to a cross-point switch fabric. The expected sequence of migration is: closed loops, small closed fabrics, and, finally, bridges, to connect optical cross-point switch fabrics. This paper presents the concept of distributed fabrics, including address assignment, frame routing, and general operation.

Investigating a method for reducing residual switch costs in cued task switching.

PubMed

Schneider, Darryl W

2016-07-01

Residual switch costs in cued task switching are performance decrements that occur despite a long cue-target interval (CTI) to prepare for a task switch. Verbruggen, Liefooghe, Vandierendonck, and Demanet (Journal of Experimental Psychology: Learning, Memory, and Cognition, 33; 342-356, 2007) showed that briefly presenting the cue during the CTI and leaving it absent after target onset yielded smaller residual switch costs than those obtained when the cue was available for the full CTI and remained present after target onset. The potential effects of cue availability during the CTI (full or partial) and cue status after target onset (present or absent) on residual switch costs were investigated in the present study. In Experiments 1 and 2, cue status was manipulated while holding cue availability constant. In Experiments 3 and 4, cue status and cue availability were manipulated factorially. Residual switch costs were obtained, but they were not modulated consistently by cue status or cue availability across experiments. In Experiment 5, a direct replication of one of Verbruggen and colleagues' experiments yielded divergent results. Implications for understanding task switching are discussed.

Denoising of genetic switches based on Parrondo's paradox

NASA Astrophysics Data System (ADS)

Fotoohinasab, Atiyeh; Fatemizadeh, Emad; Pezeshk, Hamid; Sadeghi, Mehdi

2018-03-01

Random decision making in genetic switches can be modeled as tossing a biased coin. In other word, each genetic switch can be considered as a game in which the reactive elements compete with each other to increase their molecular concentrations. The existence of a very small number of reactive element molecules has caused the neglect of effects of noise to be inevitable. Noise can lead to undesirable cell fate in cellular differentiation processes. In this paper, we study the robustness to noise in genetic switches by considering another switch to have a new gene regulatory network (GRN) in which both switches have been affected by the same noise and for this purpose, we will use Parrondo's paradox. We introduce two networks of games based on possible regulatory relations between genes. Our results show that the robustness to noise can increase by combining these noisy switches. We also describe how one of the switches in network II can model lysis/lysogeny decision making of bacteriophage lambda in Escherichia coli and we change its fate by another switch.

Numerical Simulation of Liquid Metal RF MEMS Switch Based on EWOD

NASA Astrophysics Data System (ADS)

Liu, Tingting; Gao, Yang; Yang, Tao; Guo, Huihui

2018-03-01

Conventional RF MEMS switches rely on metal-to-dielectric or metal-to-metal contacts. Some problems in the “solid-solid” contact, such as contact degradation, signal bounce and poor reliability, can be solved by using “liquid-solid” contact. The RF MEMS switch based on liquid metal is characterized by small contact resistance, no moving parts, high reliability and long life. Using electrowetting-on-dielectric (EWOD) way to control the movement of liquid metal in the RF MEMS switch, to achieve the “on” and “off” of the switch. In this paper, the electrical characteristics and RF characteristics of RF MEMS switches are simulated by fluid mechanics software FLUENT and electromagnetic simulation software HFSS. The effects of driving voltage, switching time, dielectric layer, hydrophobic layer material and thickness, switching channel height on the RF characteristics are studied. The results show that to increase the external voltage to the threshold voltage of 58V, the liquid metal began to move, and the switching time from “off” state to “on” state is 16ms. In the 0~20GHz frequency range, the switch insertion loss is less than 0.28dB, isolation is better than 23.32dB.

Optical switch based on thermocapillarity

NASA Astrophysics Data System (ADS)

Sakata, Tomomi; Makihara, Mitsuhiro; Togo, Hiroyoshi; Shimokawa, Fusao; Kaneko, Kazumasa

2001-11-01

Space-division optical switches are essential for the protection, optical cross-connects (OXCs), and optical add/drop multiplexers (OADMs) needed in future fiber-optic communication networks. For applications in these areas, we proposed a thermocapillarity switch called oil-latching interfacial-tension variation effect (OLIVE) switch. An OLIVE switch is a micro-mechanical optical switch fabricated on planar lightwave circuits (PLC) using micro-electro-mechanical systems (MEMS) technology. It consists of a crossing waveguide that has a groove at each crossing point and a pair of microheaters. The groove is partially filled with the refractive-index-matching liquid, and optical signals are switched according to the liquid's position in the groove, i.e., whether it is passing straight through the groove or reflecting at the sidewall of the groove. The liquid is driven by thermocapillarity and latched by capillarity. Using the total internal reflection to switch the optical path, the OLIVE switch exhibits excellent optical characteristics, such as high transparency (insertion loss: < 2 dB), high extinction ratio (> 50 dB), and low crosstalk (< -50 dB). Moreover, since this switch has a simple structure and bi-stability, it has wide variety of applications in wavelength division multiplexing (WDM) networks.

Design and application of gas-gap heat switches

NASA Technical Reports Server (NTRS)

Chan, C. K.; Ross, R. G., Jr.

1990-01-01

Gas-gap heat switches can serve as an effective means of thermally disconnecting a standby cryocooler when the primary (operating) cooler is connected and vice versa. The final phase of the development and test of a cryogenic heat switch designed for loads ranging from 2 watts at 8 K, to 100 watts at 80 K are described. Achieved heat-switch on/off conductance ratio ranged from 11,000 at 8 K to 2200 at 80 K. A particularly challenging element of heat-switch design is achieving satisfactory operation when large temperatures differentials exist across the switch. A special series of tests and analyses was conducted and used in this Phase-2 activity to evaluate the developed switches for temperature differentials ranging up to 200 K. Problems encountered at the maximum levels are described and analyzed, and means of avoiding the problems in the future are presented. A comprehensive summary of the overall heat-switch design methodology is also presented with special emphasis on lessons learned over the course of the 4-year development effort.

Language switching-but not foreign language use per se-reduces the framing effect.

PubMed

Oganian, Y; Korn, C W; Heekeren, H R

2016-01-01

Recent studies reported reductions of well-established biases in decision making under risk, such as the framing effect, during foreign language (FL) use. These modulations were attributed to the use of FL itself, which putatively entails an increase in emotional distance. A reduced framing effect in this setting, however, might also result from enhanced cognitive control associated with language-switching in mixed-language contexts, an account that has not been tested yet. Here we assess predictions of the 2 accounts in 2 experiments with over 1,500 participants. In Experiment 1, we tested a central prediction of the emotional distance account, namely that the framing effect would be reduced at low, but not high, FL proficiency levels. We found a strong framing effect in the native language, and surprisingly also in the foreign language, independent of proficiency. In Experiment 2, we orthogonally manipulated foreign language use and language switching to concurrently test the validity of both accounts. As in Experiment 1, foreign language use per se had no effect on framing. Crucially, the framing effect was reduced following a language switch, both when switching into the foreign and the native language. Thus, our results suggest that reduced framing effects are not mediated by increased emotional distance in a foreign language, but by transient enhancement of cognitive control, putting the interplay of bilingualism and decision making in a new light. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

ERP Correlates of Encoding Success and Encoding Selectivity in Attention Switching

PubMed Central

Yeung, Nick

2016-01-01

Long-term memory encoding depends critically on effective processing of incoming information. The degree to which participants engage in effective encoding can be indexed in electroencephalographic (EEG) data by studying event-related potential (ERP) subsequent memory effects. The current study investigated ERP correlates of memory success operationalised with two different measures—memory selectivity and global memory—to assess whether previously observed ERP subsequent memory effects reflect focused encoding of task-relevant information (memory selectivity), general encoding success (global memory), or both. Building on previous work, the present study combined an attention switching paradigm—in which participants were presented with compound object-word stimuli and switched between attending to the object or the word across trials—with a later recognition memory test for those stimuli, while recording their EEG. Our results provided clear evidence that subsequent memory effects resulted from selective attentional focusing and effective top-down control (memory selectivity) in contrast to more general encoding success effects (global memory). Further analyses addressed the question of whether successful encoding depended on similar control mechanisms to those involved in attention switching. Interestingly, differences in the ERP correlates of attention switching and successful encoding, particularly during the poststimulus period, indicated that variability in encoding success occurred independently of prestimulus demands for top-down cognitive control. These results suggest that while effects of selective attention and selective encoding co-occur behaviourally their ERP correlates are at least partly dissociable. PMID:27907075

All-optical controlled switching of solitons

NASA Astrophysics Data System (ADS)

Man, Wai Sing

1999-11-01

In this dissertation, we have numerically investigated various method of switching solitons using two different nonlinear optical switching devices, namely the twin core nonlinear directional coupler (TCNLDC) and the nonlinear optical loop mirror (NOLM). In the case of TCNLDC, four different schemes were explored where the polarization of the controlling pulse is either parallel or orthogonal to that of the signal soliton, or the controlling pulse may be launched into either of the input ports or it may have a wavelength different from that of the signal. It has been shown that high switching efficiency and distortionless propagation of the signal pulse through the coupler can only be achieved for the case in which the control pulse is launched into the adjacent port of the directional coupler and that its dispersion has equal magnitude but opposite sign as that of the signal. The effect of varying pulse width, walk-off and timing jitter were also investigated for this particular scheme for signal pulse width of 1 ps wide. In the case of NOLM, a control pulse having central wavelength located at the normal dispersion region is used to switch the soliton. The control pulse width and the NOLM's loop length were varied to obtain the switched soliton with minimum distortion and high switching efficiency. In this analysis, Raman effect is included because the control pulse transfers part of its energy to the co-propagating signal pulse in the optical loop. A compact soliton laser has also been developed for this project and its performance was analyzed experimentally and numerically. In our analysis of this soliton laser, we found that the wavelength of the mode-locked pulse can be tuned by varying the polarization elements in the laser and this is entirely due to the birefringence in the laser cavity. In summary, our works have shown that optical solitons can be switched effectively by TCNLDC and NOLM in the high bit-rate and low switching energy regime. (Abstract shortened by UMI.)

Reasons for switching ART: Comparison of data collected in 2012-2013 and 2014-2015 in Florence, Italy.

PubMed

Fusco, Francesco Maria; Burla, Maria Chiara; Degli Esposti, Anna; Pierotti, Piera; Rabatti, Loredana; Vichi, Francesca

2018-03-01

Persons living with HIV should remain on antiretroviral therapy (ART) indefinitely; however, a switch in the drug regimen is often necessary. In order to investigate if reasons for switching ART changed over time, we retrospectively analyzed reasons for switching and characteristics of switches among patients at Santa Maria Annunziata Hospital (OSMA), Florence area, Tuscany, Italy, over two periods (November 2012-October 2013 and November 2014-October 2015). The reasons for switching were classified as: simplification; virologic failure; occurrence of co-morbidities; and drug tolerability/toxicity issues. In period 1 (2012-2013), 18% patients changed their regimen vs. 13.5% in period 2 (2014-2015) (p = 0.019). Among reasons for switching, switches for simplification significantly increased from 41% in period 1 to 53% in period 2 (p = 0.004), with an increasing use of single tablet regimens (p = 0.002); no other statistically significant differences were found in other reasons for switching in periods 1 and 2. Characteristics of patients and of switches were analyzed and described. According to our data, the main reason for switching is now simplification, reflecting the recent changes in recommendations aimed to enhance adherence and quality of life, and to minimize, at the same time, drug toxicity and side effects.

Cost-effectiveness of cervical cancer screening with primary human papillomavirus testing in Norway.

PubMed

Burger, E A; Ortendahl, J D; Sy, S; Kristiansen, I S; Kim, J J

2012-04-24

New screening technologies and vaccination against human papillomavirus (HPV), the necessary cause of cervical cancer, may impact optimal approaches to prevent cervical cancer. We evaluated the cost-effectiveness of alternative screening strategies to inform cervical cancer prevention guidelines in Norway. We leveraged the primary epidemiologic and economic data from Norway to contextualise a simulation model of HPV-induced cervical cancer. The current cytology-only screening was compared with strategies involving cytology at younger ages and primary HPV-based screening at older ages (31/34+ years), an option being actively deliberated by the Norwegian government. We varied the switch-age, screening interval, and triage strategies for women with HPV-positive results. Uncertainty was evaluated in sensitivity analysis. Current cytology-only screening was less effective and more costly than strategies that involve switching to primary HPV testing in older ages. For unvaccinated women, switching at age 34 years to primary HPV testing every 4 years was optimal given the Norwegian cost-effectiveness threshold ($83,000 per year of life saved). For vaccinated women, a 6-year screening interval was cost-effective. When we considered a wider range of strategies, we found that an earlier switch to HPV testing (at age 31 years) may be preferred. Strategies involving a switch to HPV testing for primary screening in older women is expected to be cost-effective compared with current recommendations in Norway.

Economic evaluation of bone stimulation modalities: A systematic review of the literature.

PubMed

Button, Melissa L; Sprague, Sheila; Gharsaa, Osama; Latouche, Sandra; Bhandari, Mohit

2009-04-01

Various bone stimulation modalities are commonly used in treatment of fresh fractures and nonunions; however, the effectiveness and efficiency of these modalities remain uncertain. A systematic review of trials evaluating the clinical and economical outcomes of ultrasounds, electrical stimulation, and extracorporeal sound waves on fracture healing was conducted. We searched four electronic databases for economic evaluations that assessed bone stimulation modalities using ultrasound therapy, electrical stimulation, or extracorporeal shock waves. In addition, we searched the references and related articles of eligible studies, and a content expert was contacted. Information on the clinical and economical outcomes of patients was independently extracted by reviewers. Fourteen studies met the inclusion criteria; therefore, very limited research was found on the cost associated with treatments and the corresponding outcomes. The data available focus primarily on the efficacy of newly introduced treatment methods for bone growth, but failed to incorporate the costs of implementing such treatments. One economic analysis was identified that assessed different treatment paths using ultrasound. A total cost savings of 24-40% per patient occurred when ultrasound was used for fresh fractures and nonunions (grade C recommendation). The results suggest that the ultrasound is a viable alternative for bone stimulation; however, the impacts of the other modalities are left unknown due to the lack of research available. Methodological limitations leave the overall economic and clinical impact of these modalities uncertain. Large, prospective, randomized controlled trials that include cost-effectiveness analyses are needed to further define the clinical effectiveness and financial burden associated with bone stimulation modalities.

Characteristics of switching plasma in an inverse-pinch switch

NASA Technical Reports Server (NTRS)

Lee, Ja H.; Choi, Sang H.; Venable, Demetrius D.; Han, Kwang S.; Nam, Sang H.

1993-01-01

Characteristics of the plasma that switches on tens of giga volt-ampere in an inverse-pinch plasma switch (INPIStron) have been made. Through optical and spectroscopic diagnostics of the current carrying plasma, the current density, the motion of current paths, dominant ionic species have been determined in order to access their effects on circuit parameters and material erosion. Also the optimum operational condition of the plasma-puff triggering method required for azimuthally uniform conduction in the INPIStron has been determined.

Demonstration of pulse controlled all-optical switch/modulator.

PubMed

Akin, Osman; Dinleyici, M S

2014-03-15

An all-optical pulse controlled switch/modulator based on evanescent coupling between a polymer slab waveguide and a single mode fiber is demonstrated. Very fast all-optical modulation/switching is achieved via Kerr effect of the nonlinear polymer placed in the evanescent region of the optical fiber. Local refractive index perturbation (Δn=-1.45612×10(-5)) on the thin film leads to 0.374 nW power modulation at the fiber output, which results in a switching efficiency of ≈1.5%.

Evaluation of semiconductor devices for Electric and Hybrid Vehicle (EHV) ac-drive applications, volume 2

NASA Technical Reports Server (NTRS)

Lee, F. C.; Chen, D. Y.; Jovanic, M.; Hopkins, D. C.

1985-01-01

Test data of switching times characterization of bipolar transistors, of field effect transistor's switching times on-resistance and characterization, comparative data of field effect transistors, and test data of field effect transistor's parallel operation characterization are given. Data is given in the form of graphs.

A demonstration of direct access to colored stimuli following cueing by color.

PubMed

Navon, David; Kasten, Ronen

2011-09-01

To test whether cueing by color can affect orienting without first computing the location of the cued color, the impact of reorienting on the validity effect was examined. In Experiment 1 subjects were asked to detect a black dot target presented at random on either of two colored forms. The forms started being presented 750 ms before the onset of a central cue (either an arrow or a colored square). In some proportion of the trials the colors switched locations 150 ms after cue onset, simultaneously with target onset. The color switch was not found to retard responses following a color cue more than following a location cue. Furthermore, it did not reduce the validity effect of the color cue: Though the validity effect of the location cue was quite larger than the validity effect of the color cue, both effects were additive with the presence/absence of a color switch. In Experiment 2, subjects were rather asked to detect a change in shape of one of the colored forms. In this case, color switch was found to affect performance even less following a color cue. The fact that across experiments, color switch did not retard neither responding nor orienting selectively in the color cue condition, indicates that when attention is set to a certain color, reorienting to a new object following color switch does not require re-computing the address of the cued color. That finding is argued to embarrass a strong space-based view of visual attention. Copyright © 2011 Elsevier B.V. All rights reserved.

Sub-60 mV/decade switching in 2D negative capacitance field-effect transistors with integrated ferroelectric polymer

NASA Astrophysics Data System (ADS)

McGuire, Felicia A.; Cheng, Zhihui; Price, Katherine; Franklin, Aaron D.

2016-08-01

There is a rising interest in employing the negative capacitance (NC) effect to achieve sub-60 mV/decade (below the thermal limit) switching in field-effect transistors (FETs). The NC effect, which is an effectual amplification of the applied gate potential, is realized by incorporating a ferroelectric material in series with a dielectric in the gate stack of a FET. One of the leading challenges to such NC-FETs is the variable substrate capacitance exhibited in 3D semiconductor channels (bulk, Fin, or nanowire) that minimizes the extent of sub-60 mV/decade switching. In this work, we demonstrate 2D NC-FETs that combine the NC effect with 2D MoS2 channels to extend the steep switching behavior. Using the ferroelectric polymer, poly(vinylidene difluoride-trifluoroethylene) (P(VDF-TrFE)), these 2D NC-FETs are fabricated by modification of top-gated 2D FETs through the integrated addition of P(VDF-TrFE) into the gate stack. The impact of including an interfacial metal between the ferroelectric and dielectric is studied and shown to be critical. These 2D NC-FETs exhibit a decrease in subthreshold swing from 113 mV/decade down to 11.7 mV/decade at room temperature with sub-60 mV/decade switching occurring over more than 4 decades of current. The P(VDF-TrFE) proves to be an unstable option for a device technology, yet the superb switching behavior observed herein opens the way for further exploration of nanomaterials for extremely low-voltage NC-FETs.

Shifting Attention Between Visual Dimensions as a Source of Switch Costs.

PubMed

Elchlepp, Heike; Best, Maisy; Lavric, Aureliu; Monsell, Stephen

2017-04-01

Task-switching experiments have documented a puzzling phenomenon: Advance warning of the switch reduces but does not eliminate the switch cost. Theoretical accounts have posited that the residual switch cost arises when one selects the relevant stimulus-response mapping, leaving earlier perceptual processes unaffected. We put this assumption to the test by seeking electrophysiological markers of encoding a perceptual dimension. Participants categorized a colored letter as a vowel or consonant or its color as "warm" or "cold." Orthogonally to the color manipulation, some colors were eight times more frequent than others, and the letters were in upper- or lowercase. Color frequency modulated the electroencephalogram amplitude at around 150 ms when participants repeated the color-classification task. When participants switched from the letter task to the color task, this effect was significantly delayed. Thus, even when prepared for, a task switch delays or prolongs encoding of the relevant perceptual dimension.

Ferroelastic domain switching dynamics under electrical and mechanical excitations.

PubMed

Gao, Peng; Britson, Jason; Nelson, Christopher T; Jokisaari, Jacob R; Duan, Chen; Trassin, Morgan; Baek, Seung-Hyub; Guo, Hua; Li, Linze; Wang, Yiran; Chu, Ying-Hao; Minor, Andrew M; Eom, Chang-Beom; Ramesh, Ramamoorthy; Chen, Long-Qing; Pan, Xiaoqing

2014-05-02

In thin film ferroelectric devices, switching of ferroelastic domains can significantly enhance electromechanical response. Previous studies have shown disagreement regarding the mobility or immobility of ferroelastic domain walls, indicating that switching behaviour strongly depends on specific microstructures in ferroelectric systems. Here we study the switching dynamics of individual ferroelastic domains in thin Pb(Zr0.2,Ti0.8)O3 films under electrical and mechanical excitations by using in situ transmission electron microscopy and phase-field modelling. We find that ferroelastic domains can be effectively and permanently stabilized by dislocations at the substrate interface while similar domains at free surfaces without pinning dislocations can be removed by either electric or stress fields. For both electrical and mechanical switching, ferroelastic switching is found to occur most readily at the highly active needle points in ferroelastic domains. Our results provide new insights into the understanding of polarization switching dynamics as well as the engineering of ferroelectric devices.

Ferroelastic domain switching dynamics under electrical and mechanical excitations

NASA Astrophysics Data System (ADS)

Gao, Peng; Britson, Jason; Nelson, Christopher T.; Jokisaari, Jacob R.; Duan, Chen; Trassin, Morgan; Baek, Seung-Hyub; Guo, Hua; Li, Linze; Wang, Yiran; Chu, Ying-Hao; Minor, Andrew M.; Eom, Chang-Beom; Ramesh, Ramamoorthy; Chen, Long-Qing; Pan, Xiaoqing

2014-05-01

In thin film ferroelectric devices, switching of ferroelastic domains can significantly enhance electromechanical response. Previous studies have shown disagreement regarding the mobility or immobility of ferroelastic domain walls, indicating that switching behaviour strongly depends on specific microstructures in ferroelectric systems. Here we study the switching dynamics of individual ferroelastic domains in thin Pb(Zr0.2,Ti0.8)O3 films under electrical and mechanical excitations by using in situ transmission electron microscopy and phase-field modelling. We find that ferroelastic domains can be effectively and permanently stabilized by dislocations at the substrate interface while similar domains at free surfaces without pinning dislocations can be removed by either electric or stress fields. For both electrical and mechanical switching, ferroelastic switching is found to occur most readily at the highly active needle points in ferroelastic domains. Our results provide new insights into the understanding of polarization switching dynamics as well as the engineering of ferroelectric devices.

Dissociating Stimulus-Set and Response-Set in the Context of Task-Set Switching

PubMed Central

Kieffaber, Paul D.; Kruschke, John K.; Cho, Raymond Y.; Walker, Philip M.; Hetrick, William P.

2014-01-01

The primary aim of the present research was to determine how stimulus-set and response-set components of task-set contribute to switch costs and conflict processing. Three experiments are described wherein participants completed an explicitly cued task-switching procedure. Experiment 1 established that task switches requiring a reconfiguration of both stimulus- and response-set incurred larger residual switch costs than task switches requiring the reconfiguration of stimulus-set alone. Between-task interference was also drastically reduced for response-set conflict compared with stimulus-set conflict. A second experiment replicated these findings and demonstrated that stimulus- and response-conflict have dissociable effects on the “decision time” and “motor time” components of total response time. Finally, a third experiment replicated Experiment 2 and demonstrated that the stimulus- and response- components of task switching and conflict processing elicit dissociable neural activity as evidence by event-related brain potentials. PMID:22984990

Decomposing task-switching costs with the diffusion model.

PubMed

Schmitz, Florian; Voss, Andreas

2012-02-01

In four experiments, task-switching processes were investigated with variants of the alternating runs paradigm and the explicit cueing paradigm. The classical diffusion model for binary decisions (Ratcliff, 1978) was used to dissociate different components of task-switching costs. Findings can be reconciled with the view that task-switching processes take place in successive phases as postulated by multiple-components models of task switching (e.g., Mayr & Kliegl, 2003; Ruthruff, Remington, & Johnston, 2001). At an earlier phase, task-set reconfiguration (Rogers & Monsell, 1995) or cue-encoding (Schneider & Logan, 2005) takes place, at a later phase, the response is selected in accord with constraints set in the first phase. Inertia effects (Allport, Styles, & Hsieh, 1994; Allport & Wylie, 2000) were shown to affect this later stage. Additionally, findings support the notion that response caution contributes to both global as well as to local switching costs when task switches are predictable.

Stable nonlinear Mach-Zehnder fiber switch

DOEpatents

Digonnet, Michel J. F.; Shaw, H. John; Pantell, Richard H.; Sadowski, Robert W.

1999-01-01

An all-optical fiber switch is implemented within a short Mach-Zehnder interferometer configuration. The Mach-Zehnder switch is constructed to have a high temperature stability so as to minimize temperature gradients and other thermal effects which result in undesirable instability at the output of the switch. The Mach-Zehnder switch of the preferred embodiment is advantageously less than 2 cm in length between couplers to be sufficiently short to be thermally stable, and full switching is accomplished by heavily doping one or both of the arms between the couplers so as to provide a highly nonlinear region within one or both of the arms. A pump input source is used to affect the propagation characteristics of one of the arms to control the output coupling ratio of the switch. Because of the high nonlinearity of the pump input arm, low pump powers can be used, thereby alleviating difficulties and high cost associated with high pump input powers.

Assessing Instructional Modalities: Individualized Treatment Effects for Personalized Learning

ERIC Educational Resources Information Center

Beemer, Joshua; Spoon, Kelly; Fan, Juanjuan; Stronach, Jeanne; Frazee, James P.; Bohonak, Andrew J.; Levine, Richard A.

2018-01-01

Estimating the efficacy of different instructional modalities, techniques, and interventions is challenging because teaching style covaries with instructor, and the typical student only takes a course once. We introduce the individualized treatment effect (ITE) from analyses of personalized medicine as a means to quantify individual student…

pH-controlled silicon nanowires fluorescence switch

NASA Astrophysics Data System (ADS)

Mu, Lixuan; Shi, Wensheng; Zhang, Taiping; Zhang, Hongyan; She, Guangwei

2010-08-01

Covalently immobilizing photoinduced electronic transfer (PET) fluorophore 3-[N, N-bis(9-anthrylmethyl)amino]-propyltriethoxysilane (DiAN) on the surface of silicon nanowires (SiNWs) resulted a SiNWs-based fluorescence switch. This fluorescence switch is operated by adjustment of the acidity of the environment and exhibits sensitive response to pH at the range from 8 to 10. Such response is attributed to the effect of pH on the PET process. The successful combination of logic switch and SiNWs provides a rational approach to assemble different logic molecules on SiNWs for realization of miniaturization and modularization of switches and logic devices.

Voltage controlled Bi-mode resistive switching effects in MnO2 based devices

NASA Astrophysics Data System (ADS)

Hu, P.; Wu, S. X.; Wang, G. L.; Li, H. W.; Li, D.; Li, S. W.

2018-01-01

In this paper, the voltage induced bi-mode resistive switching behavior of an MnO2 thin film based device was studied. The device showed prominent bipolar resistive switching behavior with good reproducibility and high endurance. In addition, complementary resistive switching characteristics can be observed by extending the voltage bias during voltage sweep operations. The electrical measurement data and fitting results indicate that the oxygen vacancies act as defects to form a conductive path, which is connective or disrupted to realize a low resistive state or a high resistive state. Changing the sweep voltage can tune the oxygen vacancies distribution, which will achieve complementary resistive switching.

Variability in Proactive and Reactive Cognitive Control Processes Across the Adult Lifespan

PubMed Central

Karayanidis, Frini; Whitson, Lisa Rebecca; Heathcote, Andrew; Michie, Patricia T.

2011-01-01

Task-switching paradigms produce a highly consistent age-related increase in mixing cost [longer response time (RT) on repeat trials in mixed-task than single-task blocks] but a less consistent age effect on switch cost (longer RT on switch than repeat trials in mixed-task blocks). We use two approaches to examine the adult lifespan trajectory of control processes contributing to mixing cost and switch cost: latent variables derived from an evidence accumulation model of choice, and event-related potentials (ERP) that temporally differentiate proactive (cue-driven) and reactive (target-driven) control processes. Under highly practiced and prepared task conditions, aging was associated with increasing RT mixing cost but reducing RT switch cost. Both effects were largely due to the same cause: an age effect for mixed-repeat trials. In terms of latent variables, increasing age was associated with slower non-decision processes, slower rate of evidence accumulation about the target, and higher response criterion. Age effects on mixing costs were evident only on response criterion, the amount of evidence required to trigger a decision, whereas age effects on switch cost were present for all three latent variables. ERPs showed age-related increases in preparation for mixed-repeat trials, anticipatory attention, and post-target interference. Cue-locked ERPs that are linked to proactive control were associated with early emergence of age differences in response criterion. These results are consistent with age effects on strategic processes controlling decision caution. Consistent with an age-related decline in cognitive flexibility, younger adults flexibly adjusted response criterion from trial-to-trial on mixed-task blocks, whereas older adults maintained a high criterion for all trials. PMID:22073037