266 research outputs found
Panel III
Decaying Spaces: Faulkner\u27s Gothic and the Construction of the National Real / Lisa Klarr, Duke University Undisclosed Origins. A Retelling of the Story of Charles Bon in Faulkner\u27s Absalom, Absalom! / Jenna Grace Sciuto, Northeastern University Not Only Beyond the Town But Beneath It : The Geography of Abjection and Sutpen\u27s Design in Absalom, Absalom! / Erin Sweeney, University of California at Irvin
Inhibitory Control Processes and the Strategies That Support Them during Hand and Eye Movements
Background and Aims: Adaptive behavior depends on the ability to voluntarily
suppress context-inappropriate behaviors, a process referred to as response inhibition.
Stop Signal tests (SSTs) are the most frequently studied paradigm used to assess
response inhibition. Previous studies of SSTs have indicated that inhibitory control
behavior can be explained using a common model in which GO and STOP processes
are initiated independent from one and another, and the process that is completed first
determines whether the behavior is elicited (GO process) or terminated (STOP process).
Consistent with this model, studies have indicated that individuals strategically delay
their behaviors during SSTs in order to increase their stopping abilities. Despite being
controlled by distinct neural systems, prior studies have largely documented similar
inhibitory control performance across eye and hand movements. Though, no existing
studies have compared the extent to which individuals strategically delay behavior
across different effectors is not yet clear. Here, we compared the extent to which
inhibitory control processes and the cognitive strategies that support them during
oculomotor and manual motor behaviors.
Methods: We examined 29 healthy individuals who performed parallel oculomotor
and manual motor SSTs. Participants also completed a separate block of GO trials
administered prior to the Stop Signal tests to assess baseline reaction times for each
effector and reaction time increases during interleaved GO trials of the SST.
Results: Our results showed that stopping errors increased for both effectors as
the interval between GO and STOP cues was increased (i.e., stop signal delay), but
performance deteriorated more rapidly for eye compared to hand movements with
increases in stop signal delay. During GO trials, participants delayed the initiation
of their responses for each effector, and greater slowing of reaction times on GO
trials was associated with increased accuracy on STOP trials for both effectors.
However, participants delayed their eye movements to a lesser degree than their hand
movements, and strategic reaction time slowing was a stronger determinant of stopping
accuracy for hand compared to eye movements. Overall, stopping accuracies for eye
and hand movements were only modestly correlated, and the time it took individuals to
cancel a response was not related for eye and hand movements.
Discussion and Conclusion: Our findings that GO and STOP processes are
independent and that individuals strategically delay their behavioral responses to
increase stopping accuracy regardless of effector indicate that inhibitory control of
Frontiers in Psychology | www.frontiersin.org 1 December 2016 | Volume 7 | Article 1927
Schmitt et al. Inhibitory Control of Hand and Eye Movements
oculomotor and manual motor behaviors both follow common guiding principles.
Yet, our findings document that eye movements are more difficult to inhibit than
hand movements, and the timing, magnitude, and impact of cognitive control
strategies used to support voluntary response inhibition are less robust for eye
compared to hand movements. This suggests that inhibitory control systems also
show unique characteristics that are behavior-dependent. This conclusion is consistent
with neurophysiological evidence showing important differences in the architecture and
functional properties of the neural systems involved in inhibitory control of eye and hand
movements. It also suggests that characterizing inhibitory control processes in health
and disease requires effector-specific analysis.NIH Autism Center of Excellence P50HD055751; MH092696, and the Kansas Center for Autism Research and Training Research Investment Council Strategic Initiative Gran
Evaluating the cost-effectiveness of existing needle and syringe programmes in preventing hepatitis C transmission in people who inject drugs
AIM: To evaluate the cost-effectiveness of needle and syringe programmes (NSPs) compared with no NSPs on hepatitis C virus (HCV) transmission in the United Kingdom. DESIGN: Cost-effectiveness analysis from a National Health Service (NHS)/health-provider perspective, utilizing a dynamic transmission model of HCV infection and disease progression, calibrated using city-specific surveillance and survey data, and primary data collection on NSP costs. The effectiveness of NSPs preventing HCV acquisition was based on empirical evidence. SETTING AND PARTICIPANTS: UK settings with different chronic HCV prevalence among people who inject drugs (PWID): Dundee (26%), Walsall (18%) and Bristol (45%) INTERVENTIONS: Current NSP provision is compared with a counterfactual scenario where NSPs are removed for 10 years and then returned to existing levels with effects collected for 40 years. MEASUREMENTS: HCV infections and cost per quality-adjusted life year (QALY) gained through NSPs over 50 years. FINDINGS: Compared with a willingness-to-pay threshold of £20 000 per QALY gained, NSPs were highly cost-effective over a time-horizon of 50 years and decreased the number of HCV incident infections. The mean incremental cost-effectiveness ratio was cost-saving in Dundee and Bristol, and £596 per QALY gained in Walsall, with 78, 46 and 40% of simulations being cost-saving in each city, respectively, with differences driven by coverage of NSP and HCV prevalence (lowest in Walsall). More than 90% of simulations were cost-effective at the willingness-to-pay threshold. Results were robust to sensitivity analyses, including varying the time-horizon, HCV treatment cost and numbers of HCV treatments per year. CONCLUSIONS: Needle and syringe programmes are a highly effective low-cost intervention to reduce hepatitis C virus transmission, and in some settings they are cost-saving. Needle and syringe programmes are likely to remain cost-effective irrespective of changes in hepatitis C virus treatment cost and scale-up
Evaluating the validity and applicable domain of the toxic load model: Impact of concentration vs. time profile on inhalation lethality of hydrogen cyanide
The ten Berge model (or ‘‘toxic load’’ model) is often used to estimate the acute toxicity for varying combinations of inhaled concentration and duration. Expressed as Cn X t = toxic load (TL), TLs are assumed constant for various combinations of concentration (C) and time (t). Experimental data in a recent acute inhalation study of rats exposed to time-varying concentrations of hydrogen cyanide (HCN) supported the validity of the toxic load model except under very brief, discontinuous, high concentration exposures. In the present investigation, experiments were conducted to extend the evaluation of the applicable domain of the model for acute lethality of HCN in the rat (cumulative exposure range of 2900–11,000 ppm min). The lethality of HCN over very short (\u3c5 min) durations of high concentrations did not conform to the toxic load model. A value of n = 1.57 was determined for uninterrupted exposures P5 min. For 30-min exposures, the presence or absence of a gap between two exposure pulses of different concentrations, the relative duration, relative height, and the ordering of the pulses (low then high, vs. high then low) did not appear to have a meaningful impact on the toxic load required for median lethality
Neurobehavioral Abnormalities in Firest-Degree Relative of Individuals With Autism
CONTEXT: Studying sensorimotor and neurocognitive impairments in unaffected family members of individuals with autism may help identify familial pathophysiological mechanisms associated with the disorder. OBJECTIVE: To determine whether atypical sensorimotor or neurocognitive characteristics associated with autism are present in first-degree relatives of individuals with autism. DESIGN: Case-control comparison of neurobehavioral functions. SETTING: University medical center. PARTICIPANTS: Fifty-seven first-degree relatives of individuals with autism and 40 age-, sex-, and IQ-matched healthy control participants (aged 8-54 years). MAIN OUTCOME MEASURES: Oculomotor tests of sensorimotor responses (saccades and smooth pursuit); procedural learning and response inhibition; neuropsychological tests of motor, memory, and executive functions; and psychological measures of social behavior, communication skills, and obsessive-compulsive behaviors. RESULTS: On eye movement testing, family members demonstrated saccadic hypometria, reduced steady-state pursuit gain, and a higher rate of voluntary response inhibition errors relative to controls. They also showed lateralized deficits in procedural learning and open-loop pursuit gain (initial 100 milliseconds of pursuit) and increased variability in the accuracy of large-amplitude saccades that were confined to rightward movements. In neuropsychological studies, only executive functions were impaired relative to those of controls. Family members reported more communication abnormalities and obsessive-compulsive behaviors than controls. Deficits across oculomotor, neuropsychological, and psychological domains were relatively independent from one another. CONCLUSIONS: Family members of individuals with autism demonstrate oculomotor abnormalities implicating pontocerebellar and frontostriatal circuits and left-lateralized alterations of frontotemporal circuitry and striatum. The left-lateralized alterations have not been identified in other neuropsychiatric disorders and are of interest given atypical brain lateralization and language development associated with the disorder. Similar oculomotor deficits have been reported in individuals with autism, suggesting that they may be familial and useful for studies of neurophysiological and genetic mechanisms in autism
Adverse pregnancy and birth outcomes associated with Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum: a systematic review and meta-analysis.
OBJECTIVES
Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum (genital mycoplasmas) commonly colonise the urogenital tract in pregnant women. This systematic review aims to investigate their role in adverse pregnancy and birth outcomes, alone or in combination with bacterial vaginosis (BV).
METHODS
We searched Embase, Medline and CINAHL databases from January 1971 to February 2021. Eligible studies tested for any of the three genital mycoplasmas during pregnancy and reported on the primary outcome, preterm birth (PTB) and/or secondary outcomes low birth weight (LBW), premature rupture of membranes (PROM), spontaneous abortion (SA) and/or perinatal or neonatal death (PND).Two reviewers independently screened titles and abstracts, read potentially eligible full texts and extracted data. Two reviewers independently assessed risks of bias using published checklists. Random effects meta-analysis was used to estimate summary ORs (with 95% CIs and prediction intervals). Multivariable and stratified analyses were synthesised descriptively.
RESULTS
Of 57/1194 included studies, 39 were from high-income countries. In meta-analysis of unadjusted ORs, M. hominis was associated with PTB (OR 1.87, 95% CI 1.49 to 2.34), PROM, LBW and PND but not SA. U. urealyticum was associated with PTB (OR 1.84, 95% CI 1.34 to 2.55), PROM, LBW, SA and PND. U. parvum was associated with PTB (1.60, 95% CI 1.12 to 2.30), PROM and SA. Nine of 57 studies reported any multivariable analysis. In two studies, analyses stratified by BV status showed that M. hominis and U. parvum were more strongly associated with PTB in the presence than in the absence of BV. The most frequent source of bias was a failure to control for confounding.
CONCLUSIONS
The currently available literature does not allow conclusions about the role of mycoplasmas in adverse pregnancy and birth outcomes, alone or with coexisting BV. Future studies that consider genital mycoplasmas in the context of the vaginal microbiome are needed.
PROSPERO REGISTRATION NUMBER
CRD42016050962
Comparing treatment fidelity between study arms of a randomized controlled clinical trial for stroke family caregivers
OBJECTIVE:
To compare treatment fidelity among treatment arms in the Telephone Assessment and Skill-Building Kit study for stroke caregivers (TASK II) with respect to: 1) protocol adherence; 2) intervention dosage and 3) nurse intervener perspectives.
DESIGN:
A randomized controlled clinical trial design.
SETTING:
Urban, community, midwestern United States.
SUBJECTS:
A total of 254 stroke caregivers (mean ±SD age, 54.4 ±11.8 years), 55 (22.0%) males and 199 (78.4%) females) randomized to the TASK II intervention (n=123) or an Information, Support, and Referral comparison group (n=131).
INTERVENTIONS:
TASK II participants received the TASK II Resource Guide; Information, Support, and Referral participants received a standard caregiver brochure. At approximately 8 weeks after discharge, both groups received 8 weekly calls from a nurse, with a booster call 4 weeks later.
MEASURES:
Protocol adherence was evaluated with the TASK II Checklist for Monitoring Adherence. Intervention dosage was measured by the number of minutes caregivers spent reading materials and talking with the nurse. Nurse intervener perspectives were obtained through focus groups.
RESULTS:
Protocol adherence was 80% for the TASK II and 92% for the Information, Support, and Referral. As expected, intervention dosage differed between TASK II and Information, Support, and Referral with respect to caregiver time spent reading materials (t=-6.49; P<.001) and talking with the nurse (t=-7.38; P<.001). Focus groups with nurses yielded further evidence for treatment fidelity and recommendations for future trials.
CONCLUSIONS:
These findings substantiate treatment fidelity in both study arms of the TASK II stroke caregiver intervention trial (NIH R01NR010388; ClinicalTrials.govNCT01275495)
Biodegradation of the Alkaline Cellulose Degradation Products Generated during Radioactive Waste Disposal.
The anoxic, alkaline hydrolysis of cellulosic materials generates a range of cellulose degradation products (CDP) including α and β forms of isosaccharinic acid (ISA) and is expected to occur in radioactive waste disposal sites receiving intermediate level radioactive wastes. The generation of ISA's is of particular relevance to the disposal of these wastes since they are able to form complexes with radioelements such as Pu enhancing their migration. This study demonstrates that microbial communities present in near-surface anoxic sediments are able to degrade CDP including both forms of ISA via iron reduction, sulphate reduction and methanogenesis, without any prior exposure to these substrates. No significant difference (n = 6, p = 0.118) in α and β ISA degradation rates were seen under either iron reducing, sulphate reducing or methanogenic conditions, giving an overall mean degradation rate of 4.7×10−2 hr−1 (SE±2.9×10−3). These results suggest that a radioactive waste disposal site is likely to be colonised by organisms able to degrade CDP and associated ISA's during the construction and operational phase of the facility
SB-656933, a novel CXCR2 selective antagonist, inhibits ex vivo neutrophil activation and ozone-induced airway inflammation in humans
To determine the safety and tolerability of a novel selective CXCR2 antagonist and assess its pharmacodynamic effects using measures of neutrophil activation and function, including CD11b expression in whole blood and ozone-induced airway inflammation in healthy subjects
Developmental Effects on Auditory Neural Oscillatory Synchronization Abnormalities in Autism Spectrum Disorder
Previous studies have found alterations in 40 Hz oscillatory activity in response to auditory stimuli in adults with Autism Spectrum Disorder (ASD). The current study sought to examine the specificity and developmental trajectory of these findings by driving the cortex to oscillate at a range of frequencies in both children and adults with and without ASD. Fifteen participants with ASD (3 female, aged 6–23 years) and 15 age-matched controls (4 female, aged 6–25 years) underwent dense-array EEG as they listened to a carrier tone amplitude-modulated by a sinusoid linearly increasing in frequency from 0–100 Hz over 2 s. EEG data were analyzed for inter-trial phase coherence (ITPC) and single-trial power (STP). Older participants with ASD displayed significantly decreased ability to phase-lock to the stimulus in the low gamma frequency range relative to their typically developing (TD) counterparts, while younger ASD and TD did not significantly differ from each other. An interaction between age and diagnosis suggested that TD and ASD also show different developmental trajectories for low gamma power; TD showed a significant decrease in low gamma power with age, while ASD did not. Regardless of age, increased low gamma STP was significantly correlated with increased clinical scores for repetitive behaviors in the ASD group, particularly insistence on sameness. This study contributes to a growing body of evidence supporting alterations in auditory processing in ASD. Older ASD participants showed more pronounced low gamma deficits than younger participants, suggesting an altered developmental trajectory for neural activity contributing to auditory processing deficits that may also be more broadly clinically relevant. Future studies are needed employing a longitudinal approach to confirm findings of this cross-sectional study.Open Access fees paid for in whole or in part by the University of Oklahoma LibrariesYe
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