364 research outputs found
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Dysfunctional Social Reinforcement Processing in Disruptive Behavior Disorders: An Functional Magnetic Resonance Imaging Study.
ObjectivePrior functional magnetic resonance imaging (fMRI) work has revealed that children/adolescents with disruptive behavior disorders (DBDs) show dysfunctional reward/non-reward processing of non-social reinforcements in the context of instrumental learning tasks. Neural responsiveness to social reinforcements during instrumental learning, despite the importance of this for socialization, has not yet been previously investigated.MethodsTwenty-nine healthy children/adolescents and 19 children/adolescents with DBDs performed the fMRI social/non-social reinforcement learning task. Participants responded to random fractal image stimuli and received social and non-social rewards/non-rewards according to their accuracy.ResultsChildren/adolescents with DBDs showed significantly reduced responses within the caudate and posterior cingulate cortex (PCC) to non-social (financial) rewards and social non-rewards (the distress of others). Connectivity analyses revealed that children/adolescents with DBDs have decreased positive functional connectivity between the ventral striatum (VST) and the ventromedial prefrontal cortex (vmPFC) seeds and the lateral frontal cortex in response to reward relative to non-reward, irrespective of its sociality. In addition, they showed decreased positive connectivity between the vmPFC seed and the amygdala in response to non-reward relative to reward.ConclusionThese data indicate compromised reinforcement processing of both non-social rewards and social non-rewards in children/adolescents with DBDs within core regions for instrumental learning and reinforcement-based decision- making (caudate and PCC). In addition, children/adolescents with DBDs show dysfunctional interactions between the VST, vmPFC, and lateral frontal cortex in response to rewarded instrumental actions potentially reflecting disruptions in attention to rewarded stimuli
Neurodevelopmental Changes in Social Reinforcement Processing: A Functional Magnetic Resonance Imaging Study.
ObjectiveIn the current study we investigated neurodevelopmental changes in response to social and non-social reinforcement.MethodsFifty-three healthy participants including 16 early adolescents (age, 10-15 years), 16 late adolescents (age, 15-18 years), and 21 young adults (age, 21-25 years) completed a social/non-social reward learning task while undergoing functional magnetic resonance imaging. Participants responded to fractal image stimuli and received social or non-social reward/non-rewards according to their accuracy. ANOVAs were conducted on both the blood oxygen level dependent response data and the product of a context-dependent psychophysiological interaction (gPPI) analysis involving ventromedial prefrontal cortex (vmPFC) and bilateral insula cortices as seed regions.ResultsEarly adolescents showed significantly increased activation in the amygdala and anterior insula cortex in response to non-social monetary rewards relative to both social reward/non-reward and monetary non-rewards compared to late adolescents and young adults. In addition, early adolescents showed significantly more positive connectivity between the vmPFC/bilateral insula cortices seeds and other regions implicated in reinforcement processing (the amygdala, posterior cingulate cortex, insula cortex, and lentiform nucleus) in response to non-reward and especially social non-reward, compared to late adolescents and young adults.ConclusionIt appears that early adolescence may be marked by: (i) a selective increase in responsiveness to non-social, relative to social, rewards; and (ii) enhanced, integrated functioning of reinforcement circuitry for non-reward, and in particular, with respect to posterior cingulate and insula cortices, for social non-reward
Memento Mori: The development and validation of the Death Reflection Scale
Despite its potential for advancing organizational behavior (OB) research, the topic of death awareness has been vastly understudied. Moreover, research on death awareness has predominantly focused on the anxiety‐provoking aspect of death‐related cognitions, thus overlooking the positive aspect of death awareness, death reflection. This gap is exacerbated by the lack of a valid research instrument to measure death reflection. To address this issue, we offer a systematic conceptualization of death reflection, develop the Death Reflection Scale, and assess its psychometric properties across four studies. Further, using a sample of 268 firefighters, we examine whether death reflection buffers the detrimental impact of mortality cues at work on employee well‐being and safety performance. Results provide strong support for the psychometric properties of the Death Reflection Scale. Further, moderation analysis indicates death reflection weakens the negative effect of mortality cues on firefighters' safety performance. Overall, these findings suggest the newly developed Death Reflection Scale will prove useful in future research on death‐related cognitions
Coherent acoustic control of a single silicon vacancy spin in diamond
Phonons are considered to be universal quantum transducers due to their ability to couple to a wide variety of quantum systems. Among these systems, solid-state point defect spins are known for being long-lived optically accessible quantum memories. Recently, it has been shown that inversion-symmetric defects in diamond, such as the negatively charged silicon vacancy center (SiV), feature spin qubits that are highly susceptible to strain. Here, we leverage this strain response to achieve coherent and low-power acoustic control of a single SiV spin, and perform acoustically driven Ramsey interferometry of a single spin. Our results demonstrate an efficient method of spin control for these systems, offering a path towards strong spin-phonon coupling and phonon-mediated hybrid quantum systems
Comparison of the antimicrobial efficacy and germicidal efficiency of 405-nm light for surface decontamination
Background The persistence of infectious organisms on hospital surfaces presents a significant challenge to healthcare environments. Low irradiance visible 405-nm light has recently been developed as a method for environmental decontamination, with studies demonstrating successful reductions of environmental bacteria in wards and operating theatres. This study investigates the antimicrobial efficacy of 405-nm light for decontamination of surfaces, and how the dose-response kinetics are affected by use of differing light irradiances. Methods Surface-seeded Staphylococcus aureus and Pseudomonas aeruginosa (selected as model Gram-positive and Gram-negative species) were exposed to increasing doses of 405-nm light (≤ 90 Jcm-2) at three discrete irradiances (0.5, 5 and 50 mWcm-2). For both species, inactivation kinetics at each respective irradiance was established and susceptibility at equivalent light doses compared. Results Results demonstrate increased bacterial susceptibility to 405-nm light inactivation when exposed at lower irradiance treatments. For both species, 3 Jcm-2 was required when exposed using 0.5 mWcm-2 irradiance to achieve significant bacterial inactivation (P < 0.05; 26.7-73.7% reduction). When exposed at 5 mWcm-2, double the energy (6 Jcm-2) was required to achieve similar reductions. Exposure at the highest irradiance (50 mWcm-2) required 3-5 times greater dose (9-15 Jcm-2) to achieve similar reductions to the lowest irradiance tested (0.5 mWcm-2). Conclusion This study provides evidence of the enhanced germicidal efficiency of low irradiance 405-nm light, highlighting its efficacy for continuous environmental decontamination applications. Further investigation into the photo-chemical inactivation mechanisms will be crucial for its optimisation for a range of infection control applications
Editorial:The emergence of animal welfare science and policy in Africa, Asia and Latin America
Peer Reviewe
Machine-learning-accelerated Bose-Einstein condensation
Machine learning is emerging as a technology that can enhance physics
experiment execution and data analysis. Here, we apply machine learning to
accelerate the production of a Bose-Einstein condensate (BEC) of
atoms by Bayesian optimization of up to 55 control
parameters. This approach enables us to prepare BECs of
optically trapped atoms from a room-temperature gas in 575
ms. The algorithm achieves the fast BEC preparation by applying highly
efficient Raman cooling to near quantum degeneracy, followed by a brief final
evaporation. We anticipate that many other physics experiments with complex
nonlinear system dynamics can be significantly enhanced by a similar
machine-learning approach.Comment: 9 pages, 5 figures + supplemental materia
Efficacy of a low irradiance antimicrobial 405-nm visible light system for inactivation of bacteriophage Phi6 as a surrogate for SARS-CoV-2
The Covid-19 pandemic has increased the necessity for novel strategies to safely decontaminate public areas
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Chloride channels regulate differentiation and barrier functions of the mammalian airway.
The conducting airway forms a protective mucosal barrier and is the primary target of airway disorders. The molecular events required for the formation and function of the airway mucosal barrier, as well as the mechanisms by which barrier dysfunction leads to early onset airway diseases, remain unclear. In this study, we systematically characterized the developmental landscape of the mouse airway using single-cell RNA sequencing and identified remarkably conserved cellular programs operating during human fetal development. We demonstrated that in mouse, genetic inactivation of chloride channel Ano1/Tmem16a compromises airway barrier function, results in early signs of inflammation, and alters the airway cellular landscape by depleting epithelial progenitors. Mouse Ano1-/-mutants exhibited mucus obstruction and abnormal mucociliary clearance that resemble the airway defects associated with cystic fibrosis. The data reveal critical and non-redundant roles for Ano1 in organogenesis, and show that chloride channels are essential for mammalian airway formation and function
405-nm light for bacterial reduction in blood plasma : preliminary investigations into antimicrobial efficacy and plasma protein integrity
Background: Pathogen reduction technologies (PRT) for blood products can reduce the incidence of transfusion-transmitted infection and associated wastage of blood products. Visible 405nm-light has been shown to inactivate bacteria in situ in bagged blood plasma without the addition of photo-sensitive chemicals. However, threshold levels for plasma protein compatibility and optimal bactericidal activity are currently unknown. This study investigates different treatment conditions and their suitability for safely inactivating bacteria in blood plasma. Method: Plasma seeded with Staphylococcus aureus (102–105CFU/ml) was exposed to 405nm-light at low and high irradiances (10, 100mW/cm2) with treatment times ranging between 0.2–7-hr (≤252 Jcm-2). SDS-PAGE was then used to assess the light effect in terms of antimicrobial treatment levels on plasma protein integrity. Results: High and low intensity treatment regimens achieved significant bacterial inactivation (P=144 Jcm-2. Conclusion: The results of this study have highlighted the safety potential of 405nm-light treatment on blood plasma. Further research is required to determine the upper and lower threshold treatment levels and functionality of plasma proteins post-exposure for further development of this technology as a PRT tool for application in transfusion medicine
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