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Migraine refers to recurrent, unilateral headache attacks, lasting 4-72 hours, that have a pulsating quality and can occur with or without aura. Aura is a symptom, usually preceding the onset of a migraine, where there is an experience of gradually spreading focal neurological symptoms which typically last less than one hour. A meta-analysis was conducted which quantitatively synthesized literature documenting performance on clinical measures of processing speed (PS) in individuals with migraine with (MwA) and without aura (MwoA).
Participants and Methods:
Data for this study came from a larger study that compared overall neuropsychological functioning in primary headache disorders (PHD) and healthy controls (HC). We searched OneSearch and PubMed using a uniform search-strategy to locate original research comparing cognition between PHD and HC. Analyses were modeled under random effects. Hedge’s g was used as a bias-corrected estimate of effect size. We assessed between-study heterogeneity using Cochran’s Q and I2. Egger’s regression test was used to assess publication bias (i.e., the association between standard error and effect size). High heterogeneity in effects was analyzed for possible moderating variables using metaregression and sub-group analyses.
Results:
The initial search interval spanned inception-May 2021 and yielded 6692 results. Twelve studies met inclusion criteria, included clinical measures of PS, and included PHD subgroups with MwA and/or MwoA (MwA n = 279, MwoA n = 655, HC n = 2159). MwA demonstrated moderately worse performance in PS overall when compared to HC (k = 7, g = -0.41, p = 0.028). MwoA also demonstrated worse performance in PS overall when compared to HC but the effect size was small (k = 12, g = -0.21, p = 0.006). Heterogeneity of MwoA studies was low (Q = 15.12, I2 = 21.19) while heterogeneity of MwA studies was high (Q = 21.91, I2 = 72.61). Meta-regressions of MwA studies indicated clinical age and disease duration to be related to effect sizes such that studies with older clinical participants and longer disease durations yielded greater (negative) differences. Egger’s regression intercept noted a possible association effect size and standard error for MwA articles (t = 3.60, p = 0.02) and MwoA articles (t = 5.21, p < 0.005). Trim-and-fill procedure estimated 0 MwA studies to be missing due to publication bias (adjusted g = -0.41, p = 0.028) while 7 MwoA studies were estimated to be missing due to publication bias (adjusted g = -0.03, Q = 34.79).
Conclusions:
Individuals with migraine demonstrated worse performances on tests of PS compared to controls. Effect sizes were generally moderate in strength for MwA while effect sizes were generally small in strength for MwoA. This quantitative summary confirmed that individuals with migraine experience slowed processing speed in general and this effect is magnified when aura is a presenting symptom.
Research evaluating mindfulness and cognition has produced mixed results. However, variability in mindfulness has not been previously evaluated as a predictor of cognitive ability. This study evaluated the relation between intra-individual variability (IIV) in mindfulness and cognitive performance.
Participants and Methods:
274 university participants (M=19 years old, SD=1.5; 72.6% female, 67.2% White, 25.6% African American, 3.3% Asian American, 1.1% Hispanic American) completed the Five Facet Mindfulness Questionnaire (FFMQ) and the CNS Vital Signs computerized test battery. IIV was computed from the FFMQ facet T-scores. Additionally, high and low cognitive performance groups were formed from the top and bottom 16% of the sample using the neurocognition index (NCI) score from CNS Vital Signs (N=52 high NCI performance and N=46 low NCI performance).
Results:
Pearson r correlations were used to evaluate the relation between mindfulness IIV and CNS Vital Signs domains. Mindfulness IIV was negatively associated with performance on the domains of psychomotor speed [r=-.18; p=.003], composite memory [r=-.14; p=.023] and verbal memory [r=-.15; p=.015]. For the high NCI group, IIV mindfulness was positively associated with cognitive flexibility [r=.31; p=.024], executive functioning [r=.33; p=.016] and was negatively related to visual memory [r=-.28; p=.043]. For the low NCI group, IIV mindfulness was negatively related to psychomotor speed [r=-.49; p<.001], composite memory [r=-.32; p=.033] and verbal memory [r=-.31; p=.038]. There was no relation found for individual FFMQ facet scores and CNS Vital Sign domains.
Conclusions:
Increased consistency in self-reported mindfulness (lower IIV) was associated with greater processing speed and memory performance in the overall sample. However, the relation been mindfulness IIV and cognitive performance changed greatly in high NCI performers compared to low NCI performers. The low NCI group may be a proxy for poor effort which would explain why more variable self-reported mindfulness was associated with worse performance for processing speed and memory and this could be driving the results for the overall sample. However, our findings for the high NCI performance group are unique and suggest an association between increased variability in mindfulness facets and improved cognitive flexibility and executive functioning. Further study of mindfulness variability and aspects of executive functioning is warranted.
This study evaluated the relation between five-factor model (FFM) personality traits and intra-individual variability (IIV) in executive functioning (EF) using both subjective self-report and objectives measures of EF.
Participants and Methods:
165 university participants (M=19 years old, SD=1.3; 55.2% White, 35.2% African American, 72.7% female) completed the Barkley Deficits in Executive Functioning Scale-Long Form (BDEFS), IPIP-NEO Personality Inventory, Trail-Making Test (TMT) Parts A and B, and the Neuropsychological Assessment Battery (NAB) EF module. A participant’s IIV was calculated as the standard deviation around their own mean performance. Objective EF IIV was computed from T-scores for performance on Trails A, Trails B, and the NAB EF module. Subjective EF IIV was computed from T-scores for performance across BDEFS domains.
Results:
Pearson r correlations were used to evaluate the relation between subjective and objective IIV and FFM traits of personality. Subjective EF IIV was positively correlated with FFM neuroticism [r=.48; p<.001] and negatively correlated with FFM conscientiousness [r=-.43; p<.001], extraversion [r=-.18; p=.023] and agreeableness [r=-.22; p=.004]. There were no significant associations between FFM traits and objective EF IIV performance. There was additionally no significant relation between subjective EF IIV performance and objective EF IIV.
Conclusions:
Personality traits were associated with individual variability on a self-reported measure of EF but not on performance-based EF measures. These results suggest that IIV for the BDEFS was influenced by personality traits, particularly neuroticism and conscientiousness, and may reflect method variance. It was notable that IIV was not correlated between subjective and objective EF measures.
Primary headache disorder is characterized by recurrent headaches which lack underlying causative pathology or trauma. Primary headache disorder is common and encompasses several subtypes including migraine. Vestibular migraine (VM) is a subtype of migraine that causes vestibular symptoms such as vertigo, difficulties with balance, nausea, and vomiting. Literature indicates subjective and performance-based cognitive problems (executive dysfunction) among migraineurs. This study compared the magnitude of the total effect size across neuropsychological domains to determine if there is a reliable difference in effect sizes between individuals with VM and healthy controls (HC). An additional aim was to meta-analyze neuropsychological outcomes in migraine subtypes (other than VM) in reference to healthy controls.
Participants and Methods:
This study was a part of a larger study examining neuropsychological functioning and impairment in individuals with primary headache disorder and HCs. Standardized search terms were applied in OneSearch and PubMed. The search interval covered articles published from 1986 to May 2021. Analyses were random-effects models. Hedge’s g was used as a bias-corrected estimate of effect size. Between-study heterogeneity was assessed using Cochran’s Q and I2. Publication bias was assessed with Duval and Tweedie’s Trim-and-Fill method to identify evidence of missing studies.
Results:
The initial omnibus literature search yielded 6692 studies. Three studies (n=151 VM and 150 HC) met our inclusion criteria of having a VM group and reported neuropsychological performance. VM demonstrated significantly worse performance overall when compared to HCs (k=3, g=-0.99, p<0.001; Q=4.41, I2=54.66) with a large effect size. Within-domain effects of VM were: Executive Functioning=-0.99 (Q=0.62, I2=0), Screener=-1.15 (Q=3.29, I2=69.59), and Visuospatial/Construction=-1.47 (Q=0.001, I2=0.00). Compared to chronic migraine (k=3, g=-0.59, p<0.001; Q=0.68, I2=0.00) and migraine without aura (k=23, g=-0.39, p<0.001; Q=109.70, I2=79.95), VM was the only migraine subgroup to display a large effect size. Trim-and-fill procedure estimated zero VM studies to be missing due to publication bias (adjusted g=-0.99, Q=4.41).
Conclusions:
This initial attempt at a meta-analysis of cognitive deficits in VM was hampered by a lack of studies in this area. Based on our initial findings, individuals with VM demonstrated overall worse performances on neuropsychological tests compared to HCs with the greatest level of impairment seen in visuospatial/construction. Additionally, VM resulted in a large effect size while other migraine subtypes yielded small to moderate effect sizes. Despite the small sample of studies, the overall effect across neuropsychological performance was generally stable (i.e., low between-study heterogeneity). Given than VM accounts for 7% of patients seen in vertigo clinics and 9% of all migraine patients, our results suggest that neuropsychological impairment in VM deserves significantly more study.
Neurocognitive testing may advance the goal of predicting near-term suicide risk. The current study examined whether performance on a Go/No-go (GNG) task, and computational modeling to extract latent cognitive variables, could enhance prediction of suicide attempts within next 90 days, among individuals at high-risk for suicide.
Method
136 Veterans at high-risk for suicide previously completed a computer-based GNG task requiring rapid responding (Go) to target stimuli, while withholding responses (No-go) to infrequent foil stimuli; behavioral variables included false alarms to foils (failure to inhibit) and missed responses to targets. We conducted a secondary analysis of these data, with outcomes defined as actual suicide attempt (ASA), other suicide-related event (OtherSE) such as interrupted/aborted attempt or preparatory behavior, or neither (noSE), within 90-days after GNG testing, to examine whether GNG variables could improve ASA prediction over standard clinical variables. A computational model (linear ballistic accumulator, LBA) was also applied, to elucidate cognitive mechanisms underlying group differences.
Results
On GNG, increased miss rate selectively predicted ASA, while increased false alarm rate predicted OtherSE (without ASA) within the 90-day follow-up window. In LBA modeling, ASA (but not OtherSE) was associated with decreases in decisional efficiency to targets, suggesting differences in the evidence accumulation process were specifically associated with upcoming ASA.
Conclusions
These findings suggest that GNG may improve prediction of near-term suicide risk, with distinct behavioral patterns in those who will attempt suicide within the next 90 days. Computational modeling suggests qualitative differences in cognition in individuals at near-term risk of suicide attempt.
We examine temporal and spatial variation in morphology of the ammonoid cephalopod Discoscaphites iris using a large dataset from multiple localities in the Late Cretaceous (Maastrichtian) of the U.S. Gulf and Atlantic Coastal Plains, spanning a distance of 2000 km along the paleoshoreline. Our results suggest that the fossil record of D. iris is consistent with no within-species net accumulation of phyletic evolutionary change across morphological traits or the lifetime of this species. Correlations between some traits and paleoenvironmental conditions as well as changes in the coefficient of variation may support limited population-scale ecophenotypic plasticity; however, where stratigraphic data are available, no directional changes in morphology occur before the Cretaceous/Paleogene (K/Pg) boundary. This is consistent with models of “dynamic” evolutionary stasis. Combined with knowledge of life-history traits and paleoecology of scaphitid ammonoids, specifically a short planktonic phase after hatching followed by transition to a nektobenthic adult stage, these data suggest that scaphitids had significant potential for rapid morphological change in conjunction with limited dispersal capacity. It is therefore likely that evolutionary mode in the Scaphitidae (and potentially across the broader ammonoid clade) follows a model of cladogenesis wherein a dynamic morphological stasis is periodically interrupted by more substantial evolutionary change at speciation events. Finally, the lack of temporal changes in our data suggest that global environmental changes had a limited effect on the morphology of ammonoid faunas during the latest Cretaceous.
Hemorrhage remains the major cause of preventable death after trauma. Recent data suggest that earlier blood product administration may improve outcomes. The purpose of this study was to determine whether opportunities exist for blood product transfusion by ground Emergency Medical Services (EMS).
Methods
This was a single EMS agency retrospective study of ground and helicopter responses from January 1, 2011 through December 31, 2015 for adult trauma patients transported from the scene of injury who met predetermined hemodynamic (HD) parameters for potential transfusion (heart rate [HR]≥120 and/or systolic blood pressure [SBP]≤90).
Results
A total of 7,900 scene trauma ground transports occurred during the study period. Of 420 patients meeting HD criteria for transfusion, 53 (12.6%) had a significant mechanism of injury (MOI). Outcome data were available for 51 patients; 17 received blood products during their emergency department (ED) resuscitation. The percentage of patients receiving blood products based upon HD criteria ranged from 1.0% (HR) to 5.9% (SBP) to 38.1% (HR+SBP). In all, 74 Helicopter EMS (HEMS) transports met HD criteria for blood transfusion, of which, 28 patients received prehospital blood transfusion. Statistically significant total patient care time differences were noted for both the HR and the SBP cohorts, with HEMS having longer time intervals; no statistically significant difference in mean total patient care time was noted in the HR+SBP cohort.
Conclusions
In this study population, HD parameters alone did not predict need for ED blood product administration. Despite longer transport times, only one-third of HEMS patients meeting HD criteria for blood administration received prehospital transfusion. While one-third of ground Advanced Life Support (ALS) transport patients manifesting HD compromise received blood products in the ED, this represented 0.2% of total trauma transports over the study period. Given complex logistical issues involved in prehospital blood product administration, opportunities for ground administration appear limited within the described system.
MixFM, ZielinskiMD, MyersLA, BernsKS, LukeA, StubbsJR, ZietlowSP, JenkinsDH, SztajnkrycerMD. Prehospital Blood Product Administration Opportunities in Ground Transport ALS EMS – A Descriptive Study. Prehosp Disaster Med. 2018;33(3):230–236.
The use of monthly intranasal mupirocin was associated with a significant reduction in the rate of methicillin-resistant Staphylococcus aureus transmission and Staphylococcus aureus invasive infection in a large neonatal intensive care unit. Resistance to mupirocin emerged over time, but it was rare and was not associated with adverse clinical outcomes.
Many agricultural producers face cash price distributions that are effectively truncated at a lower limit through participation in farm programs designed to support farm prices and incomes. For example, the 1996 Federal Agricultural Improvement Act (FAIR) makes many producers eligible to obtain marketing loans which truncate their cash price realization at the loan rate, while allowing market prices to freely equilibrate supply and demand. This paper studies the effects of truncated cash price distributions on the optimal use of futures and options. The results show that truncation in the cash price distribution facing an individual producer provides incentives to trade options as well as futures. We derive optimal futures and options trading rules under a range of different truncation scenarios. Empirical results highlight the impacts of basis risk and yield risk on the optimal futures and options portfolio.
Pea aphids can avoid ladybug predators by dropping from the food plant when disturbed. Once off the plant the aphid must find another food plant. If temperatures on the ground are high, the aphid may die before finding a new food plant. In Kamloops, B.C., summers are hot and dry, compared with Vancouver where the climate is warm and moist. Pea aphids from Kamloops generally exhibit back-up behaviour and rarely drop from the plant when approached by a ladybug. By contrast, Vancouver pea aphids readily drop from the plant when disturbed by a predator. Adult aphids from Kamloops are more tolerant of heat under moist conditions at 37.5 °C than Vancouver adults but under dry conditions and at 42 °C, both groups have similar survival times. First instars of both aphid biotypes die sooner at high temperatures than adults. Mortality of aphids on the ground is sufficiently high to select against dropping behaviour as a first line defense against predators in areas with hot, dry climates.
Tests of thyroid function and pathology were carried out on 133 patients before they were treated with lithium (Li+). Of the 12 patients who subsequently became hypothyroid during treatment with lithium 9 had, before the commencement of treatment, thyroid autoantibodies and/or an exaggerated thyroid stimulating hormone (TSH) response to thyrotropin releasing hormone (TRH), whereas 3 patients had neither of these indicators. Lithium administration was accompanied by a rise in thyroid antibody titre in 20 patients but a fall in only 5, a statistically significant difference. Evidence that it may be an immunostimulant is discussed. Li+-induced thyroid failure cannot be accurately predicted, and may occur suddenly. The best minimum safeguard, therefore, is serial thyroxine (T4) (or free T4) estimation, supplemented if equivocal by a free thyroxine index (FTI), a basal TSH and, if doubt remains, by a TRH test.
Monthly hospital admission rates (HA) for mania were classified by sex, type of admission (first, or re-admission) and by country (England and Wales or Scotland). Of the 8 classes thus created, all but one showed a statistically significant annual cycle with a peak in Summer and trough in Winter. There was no significant difference in phase or amplitude between male and female cycles. A linear increase in yearly re-admission rates was found during the 8 years of the English and the 11 years of the Scottish data.
Current month's mean daily temperature (lag0) and last month's (lag1) mean day-length and mean daily hours of sunshine correlated better with admission rate than did the values for other months. In a multiple regression analysis temperature made the other 2 climatic variables redundant in accounting for variation in HA.
This study validates the GHQ-28 on a sample of paralysed, spinally injured outpatients under the care of the West Midlands Spinal Injuries Unit. The validity of the GHQ-28 was 0·83 (95% confidence interval: 0·70 to 0·93) using the Clinical Interview Schedule (CIS) as the validating criterion. The effectiveness of the GHQ-28 as a screening instrument using CIS 11/12 as case criterion, and thus a prevalence rate of 0·18, was judged by relative operating characteristic (ROC) analysis. The area under the ROC curve was 0·91±0·03. “Optimum’ discrimination occurred near GHQ 3/4 (0011 scoring scheme) giving a sensitivity of 0·81, a specificity of 0·82 and a misclassification rate of 18%.
The need for small form factor, portable biosensing platforms is prevalent across a wide range of medical, environmental, and defense applications. This paper presents the design of a novel, integrated optofluidic photonic crystal biosensor architecture that shows potential for meeting the single molecule detection requirements of these application areas. GaN is being targeted as the photonic crystal slab material due to its transparency in the visible spectral range and also the potential for creating high aspect ratio photonic crystal lattices via polarity inverted MBE growth. Results of optical modeling efforts indicating 10-15x resonant enhancement of fluorescent emission and polarity inversion GaN growth techniques will be discussed.
The Use of Cathodoluminescence in Gallium Nitride During Growth to Determine Substrate Temperature Accurate measurement of the substrate temperature during growth of gallium nitride by molecular beam epitaxy is crucial. Typically, thermocouples are usually used to measure the temperature of the back side of block which is holding the substrate. Alternatively, pyrometers are often used. However, there is a big range of an error. In-situ cathodoluminescence (CL) occurring during reflection high energy electron diffraction is a strong candidate to determine the growth temperature. The electron beam supplied by our RHEED gun has an energy of 13keV which was used for each measurement. CL was easily detected up to and beyond typical growth temperatures. The CL was directed into a monochromator using fiber optics. The final signal was detected with a photomultiplier tube. This technique appears quite useful to accurately and reproducably determine substrate temperature during growth.
The CL could also be observed using a ccd camera. Thus, we investigated using the CL to image the sample during growth. This could be used to see temperature inhomogenaities, and potentially to map alloy composition fluctuations. We calibrated the wavelength vs. growth temperature by using narrow band-pass interference filters. Background subtraction with blanking the e-beam could be used to remove black body radiation and other undesired sources of light. For gallium nitride, the photon energy at the growth temperature of 750°C is about 3.0eV. Using different filters, we can take a picture of e-beam on the surface of substrate for each filter and analyze the peak intensity using the line profile. We will present CL images of various samples at differing temperatures.
This work was supported by the AFOSR MURI F49620-03-1-0330 monitored by Todd Steiner and Gerald Witt and by ONR Grants N00014-02-1-0974 and N00014-01-1-0571, both monitored by Colin E. C. Wood.
GaAs1−xNx layers and quantum dot-like structures were grown on (100) GaAs substrates by molecular beam epitaxy. The dependence of photoluminescence emission spectra on annealing temperature is consistent with literature at lower temperatures but after annealing at 750 °C a net red-shift is consistently observed. X-ray photoelectron spectroscopy measurements indicate that for different annealing times and temperatures, the nitrogen and arsenic surface concentrations changed compared to that of as-grown samples, specifically arsenic is lost from the material. Raman measurements are consistent with the trends in photoluminescence and also suggest the loss of arsenic occurs at higher annealing temperatures in both samples capped with GaAs and uncapped samples.
Reflection high-energy electron diffraction total-reflection-angle x-ray spectroscopy (RHEED-TRAXS) uses high-energy electrons from RHEED to excite x-ray fluorescence. Monitoring characteristic x-rays of selected elements thus allows study of surface coverage of materials. In this study, surface coverage of Ga and In during growth of GaN and InGaN was probed using this technique. Evolution of the surface layer of Ga on GaN during growth and deposition of Ga on static GaN at room temperature were studied. RHEED-TRAXS measurements were performed during growth of InGaN by measuring the ratio of the In Lα to Ga Kα intensity. A significant surface coverage of In was observed at all temperatures investigated regardless of actual In incorporation.