The problem with online data collection: predicting invalid responding in undergraduate samples

The popularity of online research is increasing but the validity of the results obtained is not yet clear. The purpose of this study was to examine the factors that influence the validity of computerized data collection in an undergraduate sample. Participants were 99 university students randomly assigned to one of three data collection conditions: online survey platform, in-person computerized survey platform, and in-person pencil-and-paper survey. Results from statistical analyses suggest self-reported inattention symptoms, exposure to more stressors, and computerized platforms predict more invalid responding. In contrast, personality, self-reported impulsivity symptoms, and shorter completion times do not predict invalid responding. Overall, more than half of the participants failed at least one validity check and 11% failed three or more validity checks. Researchers, particularly those working with undergraduate samples, should consider implementing procedures to ensure the data collected are valid

Mindfulness Correlates with Stress and Coping in University Students

Mindfulness has received significant attention in the empirical literature during the past decade, but few studies have focused on mindfulness in university students and how it may influence problematic behaviours. This study examined the relationships among mindfulness, coping, and physiological reactivity in a sample of university students. Participants completed questionnaires, and skin conductance measurements were collected during an interview where they recalled a personally stressful event. Correlation analyses tested relationships among these variables. There was a negative correlation between substance use and mindfulness. Specifically, those using substances as a coping mechanism were less likely to be mindful and displayed higher physiological reactivity. More mindful individuals were less likely to report misusing substances and were able to calm themselves more quickly than their counterparts following a stressful event. Thus, poor outcomes for distressed students may be reduced with mindfulness-based interventions.  Au cours des dernières décennies, la pleine conscience a été l’objet d’une attention importante dans la documentation empirique, mais peu d’études ont ciblé la pleine conscience chez les étudiants et sa façon d’influencer les comportements problématiques. Cette étude a étudié l’association entre la pleine conscience, les mécanismes d’adaptation et la réactivité physiologique chez un échantillon d’étudiants. En plus de répondre à des questionnaires, les participants ont dû passer une entrevue où il leur fallait raconter un souvenir personnel particulièrement stressant pendant qu’on mesurait leur conductance cutanée. Des analyses de corrélation ont évalué les liens entre ces variables. Ainsi, on a dénoté une corrélation négative entre l’utilisation de substances nocives et la pleine conscience. Plus précisément, les participants qui avaient consommé des substances nocives comme mécanisme d’adaptation avaient moins tendance à posséder des traits conscients, et ont démontré une réactivité physiologique plus élevée que les autres étudiants. Les gens plus pleinement conscients avaient moins tendance à utiliser des substances nocives, et étaient capables de se calmer plus rapidement que leurs pairs après un événement stressant. Par conséquent, des interventions basées sur la pleine conscience pourraient aider les étudiants stressés à ne pas adopter de comportements problématiques

Risk Factors for Cannabis Use-Related Consequences in Emerging Adults

Cannabis use in Canada is a public health concern, especially it has been legalized for medical and recreational use. Although widely used, it appears there are negative consequences for some, but not all, cannabis consumers, and it remains challenging to predict which individuals will experience difficulties. This study examines the role of several risk factors in predicting negative outcomes of cannabis use in university students with a particular focus on personality and mental health variables. Undergraduate students (N=370) enrolled in a southwestern Ontario university participated in an online study. Preliminary analyses suggested that higher stress and lower conscientiousness were associated with cannabis use. In follow-up analyses, perceived stress was significantly associated with functional consequences of cannabis use when the quantity of cannabis used was accounted for in the analyses. Agreeableness and conscientiousness were significantly associated with overall GPA after controlling for amount of cannabis used. Individuals using low-to-moderate levels of cannabis had fewer functional consequences than individuals using higher amounts of cannabis, but these groups could not be differentiated in terms of their overall GPA. These results address a niche in the field of cannabis research in higher education and have significant implications in terms of policy and clinical practice

Arkansas Wheat Cultivar Performance Tests 2019-2020

Wheat cultivar performance tests are conducted each year in Ark- ansas by the University of Arkansas System Division of Agriculture’s Arkansas Agricultural Experiment Station, Department of Crop, Soil, and Environmental Sciences. The tests provide informa- tion to companies developing cultivars and marketing seed within the state and aid the Arkansas Cooperative Extension Service in formulating cultivar recommendations for small-grain producers. The tests are conducted at the Northeast Research and Extension Center at Keiser, the Vegetable Substation near Kibler, the Lon Mann Cotton Research Station near Marianna, the Newport Extension Center near Newport, the Rohwer Research Station near Rohwer, the Pine Tree Research Station near Colt, and the Hope Research and Extension Center. In addition, entries are evaluated in a stripe rust (Puccinia striiformis f.sp. tritici) inoculated nursery in Fayetteville and a Fusarium head blight (FHB) inoculated nursery in Newport and Fayetteville. Specific location and cultural practice information accompany each table

Early frontotemporal dementia targets neurons unique to apes and humans

Objective: Frontotemporal dementia (FTD) is a neurodegenerative disease that erodes uniquely human aspects of social behavior and emotion. The illness features a characteristic pattern of early injury to anterior cingulate and frontoinsular cortex. These regions, though often considered ancient in phylogeny, are the exclusive homes to the von Economo neuron (VEN), a large bipolar projection neuron found only in great apes and humans. Despite progress toward understanding the genetic and molecular bases of FTD, no class of selectively vulnerable neurons has been identified. Methods: Using unbiased stereology, we quantified anterior cingulate VENs and neighboring Layer 5 neurons in FTD (n = 7), Alzheimer's disease (n = 5), and age‐matched nonneurological control subjects (n = 7). Neuronal morphology and immunohistochemical staining patterns provided further information about VEN susceptibility. Results: FTD was associated with early, severe, and selective VEN losses, including a 74% reduction in VENs per section compared with control subjects. VEN dropout was not attributable to general neuronal loss and was seen across FTD pathological subtypes. Surviving VENs were often dysmorphic, with pathological tau protein accumulation in Pick's disease. In contrast, patients with Alzheimer's disease showed normal VEN counts and morphology despite extensive local neurofibrillary pathology. Interpretation: VEN loss links FTD to its signature regional pattern. The findings suggest a new framework for understanding how evolution may have rendered the human brain vulnerable to specific forms of degenerative illness

Identification of a Phosphorylation Site for Calcium/Calmodulindependent Protein Kinase II in the NR2B Subunit of the N-Methyl-D-aspartate Receptor

The N-methyl-D-aspartate (NMDA) subtype of excitatory glutamate receptors plays critical roles in embryonic and adult synaptic plasticity in the central nervous system. The receptor is a heteromultimer of core subunits, NR1, and one or more regulatory subunits, NR2A-D. Protein phosphorylation can regulate NMDA receptor function (Lieberman, D. N., and Mody, I. (1994) Nature 369, 235-239; Wang, Y. T., and Salter, M. W. (1994) Nature 369, 233-235; Wang, L.-Y., Orser, B. A., Brautigan, D. L., and MacDonald, J. F. (1994) Nature 369, 230-232). Here we identify a major phosphorylation site on subunit NR2B that is phosphorylated by Ca2+/calmodulin-dependent protein kinase II (CaM kinase II), an abundant protein kinase located at postsynaptic sites in glutamatergic synapses. For the initial identification of the site, we constructed a recombinant fusion protein containing 334 amino acids of the C terminus of the NR2B subunit and phosphorylated it with CaM kinase II in vitro. By peptide mapping, automated sequencing, and mass spectrometry, we identified the major site of phosphorylation on the fusion protein as Ser-383, corresponding to Ser-1303 of full-length NR2B. The Km for phosphorylation of this site in the fusion protein was ~50 nM, much lower than that of other known substrates for CaM kinase II, suggesting that the receptor is a high affinity substrate. We show that serine 1303 in the full-length NR2B and/or the cognate site in NR2A is a major site of phosphorylation of the receptor both in the postsynaptic density fraction and in living hippocampal neurons

Which executive functioning deficits are associated with AD/HD, ODD/CD and comorbid AD/HD+ODD/CD?

Item does not contain fulltextThis study investigated (1) whether attention deficit/hyperactivity disorder (AD/HD) is associated with executive functioning (EF) deficits while controlling for oppositional defiant disorder/conduct disorder (ODD/CD), (2) whether ODD/CD is associated with EF deficits while controlling for AD/HD, and (3)~whether a combination of AD/HD and ODD/CD is associated with EF deficits (and the possibility that there is no association between EF deficits and AD/HD or ODD/CD in isolation). Subjects were 99~children ages 6–12 years. Three putative domains of EF were investigated using well-validated tests: verbal fluency, working memory, and planning. Independent of ODD/CD, AD/HD was associated with deficits in planning and working memory, but not in verbal fluency. Only teacher rated AD/HD, but not parent rated AD/HD, significantly contributed to the prediction of EF task performance. No EF deficits were associated with ODD/CD. The presence of comorbid AD/HD accounts for the EF deficits in children with comorbid AD/HD+ODD/CD. These results suggest that EF deficits are unique to AD/HD and support the model proposed by R. A. Barkley (1997).17 p

Frustrated 3-Dimensional Quantum Spin Liquid in CuHpCl

Inelastic neutron scattering measurements are reported for the quantum antiferromagnetic material Cu_2(C_5H_12N_2)_2Cl_4 (CuHpCl). The magnetic excitation spectrum forms a band extending from 0.9 meV to 1.4 meV. The spectrum contains two modes that disperse throughout the a-c plane of the monoclinic unit cell with less dispersion along the unique b-axis. Simple arguments based on the measured dispersion relations and the crystal structure show that a spin ladder model is inappropriate for describing CuHpCl. Instead, it is proposed that hydrogen bond mediated exchange interactions between the bi-nuclear molecular units yield a three-dimensional interacting spin system with a recurrent triangular motif similar to the Shastry-Sutherland Model (SSM). Model independent analysis based on the first moment sum rule shows that at least four distinct spin pairs are strongly correlated and that two of these, including the dimer bond of the corresponding SSM, are magnetically frustrated. These results show that CuHpCl should be classified as a frustration induced three dimensional quantum spin liquid.Comment: 13 pages, 17 figures (Color) ReSubmitted to Phys. Rev. B 9/21/2001 resubmission has new content email comments to [email protected] or [email protected]

Timescales of Massive Human Entrainment

The past two decades have seen an upsurge of interest in the collective behaviors of complex systems composed of many agents entrained to each other and to external events. In this paper, we extend concepts of entrainment to the dynamics of human collective attention. We conducted a detailed investigation of the unfolding of human entrainment - as expressed by the content and patterns of hundreds of thousands of messages on Twitter - during the 2012 US presidential debates. By time locking these data sources, we quantify the impact of the unfolding debate on human attention. We show that collective social behavior covaries second-by-second to the interactional dynamics of the debates: A candidate speaking induces rapid increases in mentions of his name on social media and decreases in mentions of the other candidate. Moreover, interruptions by an interlocutor increase the attention received. We also highlight a distinct time scale for the impact of salient moments in the debate: Mentions in social media start within 5-10 seconds after the moment; peak at approximately one minute; and slowly decay in a consistent fashion across well-known events during the debates. Finally, we show that public attention after an initial burst slowly decays through the course of the debates. Thus we demonstrate that large-scale human entrainment may hold across a number of distinct scales, in an exquisitely time-locked fashion. The methods and results pave the way for careful study of the dynamics and mechanisms of large-scale human entrainment.Comment: 20 pages, 7 figures, 6 tables, 4 supplementary figures. 2nd version revised according to peer reviewers' comments: more detailed explanation of the methods, and grounding of the hypothese

Bayesian robustness for decision making problems: Applications in medical contexts

AbstractPractical implementation of Bayesian decision making is hindered by the fact that optimal decisions may be sensitive to the model inputs: the prior, the likelihood and/or the underlying utility function. Given the structure of a problem, the analyst has to decide which sensitivity measures are relevant and compute them efficiently. We address the issue of robustness of the optimal action in a decision making problem with respect to the prior model and the utility function. We discuss some general principles and apply novel computational strategies in the context of two relatively complex medical decision making problems