1,161 research outputs found

    Motor affordance and its role for visual working memory: evidence from fMRI studies

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    We examined the role of motor affordances of objects for working memory retention processes. Three experiments are reported in which participants passively viewed pictures of real world objects or had to retain the objects in working memory for a comparison with an S2 stimulus. Brain activation was recorded by means of functional magnetic resonance imaging (fMRI). Retaining information about objects for which hand actions could easily be retrieved (manipulable objects) in working memory activated the hand region of the ventral premotor cortex (PMC) contralateral to the dominant hand. Conversely, nonmanipulable objects activated the left inferior frontal gyrus. This suggests that working memory for objects with motor affordance is based on motor programs associated with their use. An additional study revealed that motor program activation can be modulated by task demands: Holding manipulable objects in working memory for an upcoming motor comparison task was associated with left ventral PMC activation. However, retaining the same objects for a subsequent size comparison task led to activation in posterior brain regions. This suggests that the activation of hand motor programs are under top down control. By this they can flexibly be adapted to various task demands. It is argued that hand motor programs may serve a similar working memory function as speech motor programs for verbalizable working memory contents, and that the premotor system mediates the temporal integration of motor representations with other task-relevant representations in support of goal oriented behavior

    Far-Right Extremism’s Threat to Police Safety and the Organizational Legitimacy of Law Enforcement in the United States

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    Objective: to analyze the far-right extremism’s anti- government ideology as an external threat to law enforcement officers. Methods: dialectical approach to cognition of social phenomena, using the general and specific research methods based on it.Results: The relationship between far-right extremism and law enforcement in the United States has a long and complicated history. In 2020, this relationship was on display as both far-right extremists and law enforcement agencies were brought into the national spotlight for their roles in multiple unprecedented events. This research discusses how far-right extremism’s anti- government ideology represents an external threat to law enforcement officers. This threat is discussed through the presentation of 30-years of data on law enforcement officers killed in the line-of-duty by far-right extremists from the Extremist Crime Database. In addition, the research also examines law enforcement’s implicit and explicit support for far-right extremism, which creates an internal threat against the legitimacy of the profession. Finally, policy initiatives that come from, and build upon, prior research are discussed to reduce these threats.Scientific novelty: for the first time, the work substantiates that far-right extremists threaten the safety of law enforcement officers in the United States. Antigovernment extremists, who do not believe that they are subject to the laws of the jurisdiction where they live, pose the risk of escalating to violent acts when encountering law enforcement when they engage in both ideologically motivated and routine criminal activity. In addition, law enforcement agencies who hire far-right extremists face the very real prospect of becoming illegitimate in the eyes of the communities to whom they are sworn to serve and protect. Decades of criminological research has shown that lack of trust in law enforcement makes the job of policing a community more difficult and more dangerous. Although multiple paths forward were outlined that build on prior research and empirical knowledge, only decisive action by law enforcement and policymakers will result in outcomes that reduce the risk of external violent victimization to police and protect law enforcement agencies from being delegitimized by the presence of far-right extremists within their ranks.Practical significance: the main provisions and conclusions of the article can be used in scientific, pedagogical and law enforcement activities when considering issues related to the prevention, suppression and investigation of extremist crimes.The article was first published in English language by Criminology, Criminal Justice, Law & Society and The Western Society of Criminology Hosting by Scholastica. For more information please contact: [email protected] original publication: Parkin, W. S., Mills, C. E., Gruenewald, J. (2021). Far-Right Extremism’s Threat to Police Safety and the Organizational Legitimacy of Law Enforcement in the United States, Criminology, Criminal Justice, Law & Society, 2021, Vol. 22, No. 2, pp. 1–24. Publication URL: https://ccjls.scholasticahq.com/article/26321-far-right-extremism-s-threat-to-police-safety-and-the-organizational-legitimacy-of-law-enforcement-in-the-united-state

    Two-Fermion Production in Electron-Positron Collisions

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    This report summarizes the results of the two-fermion working group of the LEP2-MC workshop, held at CERN from 1999 to 2000. Recent developments in the theoretical calculations of the two fermion production process in the electron-positron collision at LEP2 center of the mass energies are reported. The Bhabha process and the production of muon, tau, neutrino and quark pairs is covered. On the basis of comparison of various calculations, theoretical uncertainties are estimated and compared with those needed for the final LEP2 data analysis. The subjects for the further studies are identified.Comment: 2-fermion working group report of the LEP2 Monte Carlo Workshop 1999/2000, 113 pages, 24 figures, 35 table

    Giant persistent photoconductivity in monolayer MoS2 field-effect transistors

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    Monolayer transition metal dichalcogenides (TMD) have numerous potential applications in ultrathin electronics and photonics. The exposure of TMD-based devices to light generates photo-carriers resulting in an enhanced conductivity, which can be effectively used, e.g., in photodetectors. If the photo-enhanced conductivity persists after removal of the irradiation, the effect is known as persistent photoconductivity (PPC). Here we show that ultraviolet light (λ = 365 nm) exposure induces an extremely long-living giant PPC (GPPC) in monolayer MoS2 (ML-MoS2) field-effect transistors (FET) with a time constant of ~30 days. Furthermore, this effect leads to a large enhancement of the conductivity up to a factor of 107. In contrast to previous studies in which the origin of the PPC was attributed to extrinsic reasons such as trapped charges in the substrate or adsorbates, we show that the GPPC arises mainly from the intrinsic properties of ML-MoS2 such as lattice defects that induce a large number of localized states in the forbidden gap. This finding is supported by a detailed experimental and theoretical study of the electric transport in TMD based FETs as well as by characterization of ML-MoS2 with scanning tunneling spectroscopy, high-resolution transmission electron microscopy, and photoluminescence measurements. The obtained results provide a basis for the defect-based engineering of the electronic and optical properties of TMDs for device applications

    Four-Fermion Production in Electron-Positron Collisions

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    This report summarises the results of the four-fermion working group of the LEP2-MC workshop, held at CERN from 1999 to 2000. Recent developments in the calculation of four-fermion processes in electron-positron collisions at LEP-2 centre-of-mass energies are presented, concentrating on predictions for four main reactions: W-pair production, visible photons in four-fermion events, single-W production and Z-pair production. Based on a comparison of results derived within different approaches, theoretical uncertainties on these predictions are established.Comment: 150 pages, 73 figures, 45 table

    Growing Environmental Activists: Developing Environmental Agency and Engagement Through Children’s Fiction.

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    We explore how story has the potential to encourage environmental engagement and a sense of agency provided that critical discussion takes place. We illuminate this with reference to the philosophies of John Macmurray on personal agency and social relations; of John Dewey on the primacy of experience for philosophy; and of Paul Ricoeur on hermeneutics, dialogue, dialectics and narrative. We view the use of fiction for environmental understanding as hermeneutic, a form of conceptualising place which interprets experience and perception. The four writers for young people discussed are Ernest Thompson Seton, Kenneth Grahame, Michelle Paver and Philip Pullman. We develop the concept of critical dialogue, and link this to Crick's demand for active democratic citizenship. We illustrate the educational potential for environmental discussions based on literature leading to deeper understanding of place and environment, encouraging the belief in young people that they can be and become agents for change. We develop from Zimbardo the key concept of heroic resister to encourage young people to overcome peer pressure. We conclude with a call to develop a greater awareness of the potential of fiction for learning, and for writers to produce more focused stories engaging with environmental responsibility and activism

    Socioeconomic position across the lifecourse & allostatic load: data from the West of Scotland Twenty-07 cohort study

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    Background: We examined how socioeconomic position (SEP) across the lifecourse (three critical periods, social mobility and accumulated over time) is associated with allostatic load (a measure of cumulative physiological burden). Methods. Data are from the West of Scotland Twenty-07 Study, with respondents aged 35 (n = 740), 55 (n = 817) and 75 (n = 483). SEP measures representing childhood, the transition to adulthood and adulthood SEP were used. Allostatic load was produced by summing nine binary biomarker scores (1 = in the highest-risk quartile). Linear regressions were used for each of the lifecourse models; with model fits compared using partial F-tests. Results: For those aged 35 and 55, higher SEP was associated with lower allostatic load (no association in the 75-year-olds). The accumulation model (more time spent with higher SEP) had the best model fit in those aged 35 (b = -0.50, 95%CI = -0.68, -0.32, P = 0.002) and 55 (b = -0.31, 95%CI = -0.49, -0.12, P < 0.001). However, the relative contributions of each life-stage differed, with adulthood SEP less strongly associated with allostatic load. Conclusions: Long-term, accumulated higher SEP has been shown to be associated with lower allostatic load (less physiological burden). However, the transition to adulthood may represent a particularly sensitive period for SEP to impact on allostatic load. © 2014 Robertson et al.; licensee BioMed Central Ltd

    Associations Between Air Pollution Exposure and Empirically Derived Profiles of Cognitive Performance in Older Women

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    Background:Elucidating associations between exposures to ambient air pollutants and profiles of cognitive performance may provide insight into neurotoxic effects on the aging brain. Objective:We examined associations between empirically derived profiles of cognitive performance and residential concentrations of particulate matter of aerodynamic diameter \u3c 2.5 (PM2.5) and nitrogen dioxide (NO2) in older women. Method:Women (N = 2,142) from the Women’s Health Initiative Study of Cognitive Aging completed a neuropsychological assessment measuring attention, visuospatial, language, and episodic memory abilities. Average yearly concentrations of PM2.5 and NO2 were estimated at the participant’s addresses for the 3 years prior to the assessment. Latent profile structural equation models identified subgroups of women exhibiting similar profiles across tests. Multinomial regressions examined associations between exposures and latent profile classification, controlling for covariates. Result:Five latent profiles were identified: low performance across multiple domains (poor multi-domain; n = 282;13%), relatively poor verbal episodic memory (poor memory; n = 216; 10%), average performance across all domains (average multi-domain; n = 974; 45%), superior memory (n = 381; 18%), and superior attention (n = 332; 15%). Using women with average cognitive ability as the referent, higher PM2.5 (per interquartile range [IQR] = 3.64ÎŒg/m3) was associated with greater odds of being classified in the poor memory (OR = 1.29; 95% Confidence Interval [CI] = 1.10–1.52) or superior attention (OR = 1.30; 95% CI = 1.10–1.53) profiles. NO2 (per IQR = 9.86 ppb) was associated with higher odds of being classified in the poor memory (OR = 1.38; 95% CI = 1.17–1.63) and lower odds of being classified with superior memory (OR = 0.81; 95% CI = 0.67–0.97). Conclusion:Exposure to PM2.5 and NO2 are associated with patterns of cognitive performance characterized by worse verbal episodic memory relative to performance in other domains
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