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21.
This article reports the results of a positive youth development (PYD) intervention for adolescents in alternative high schools (209 African American and Hispanic American adolescents, aged 14–18; 118 females and 91 males). The intervention was guided by a self‐transformative model of PYD (Eichas, Meca, Montgomery, & Kurtines, 2014). This model proposes that the actions youth take to define themselves function as active ingredients in positive development over the life course. Consistent with the self‐transformative model, results provided support for direct or mediated intervention effects on the self‐transformative processes of self‐construction and self‐discovery, life goal development, identity synthesis, and internalizing problems. The findings illustrate the utility of using a self‐transformative approach to PYD in work with marginalized youth populations.  相似文献   
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Modern patent systems are slow, inefficient, expensive, and may result in outcomes that actively harm technological progress. This paper proposes a substantive re-think of these systems and lays a foundation upon which practical solutions can be built. Many solutions proposed in the past, such as prior-art bounties, outsourced examination, and dynamic fee setting, have gone unheeded due to the cost of administering them and the rigidity of the patent system. We explore how distributed ledger technologies (DLTs) enable these major changes by altering the way stakeholders are able to interact with the patent records system. We find that transitioning to a DLT-based patent records system can enable many previously suggested improvements to current patent systems in a flexible, scalable, and transparent manner. The case for such a transition is strengthened when jointly considering the complex but common roots of problems facing modern patent systems, rather than a balkanised set of technical solutions to address each issue independently. Noting that a DLT-based system is not a panacea, we also provide comment on the political, legal, and organisational challenges that must be overcome for such changes to be implemented at scale.  相似文献   
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Joint presentations of a conditioned stimulus (CS) and an unconditioned stimulus (US) strengthen the contingency between them, whereas presentations of one stimulus without the other degrade this contingency. For example, the CS can be presented without the US either before conditioning (CS–no US and then CS–US; latent inhibition) or after conditioning (CS–US and then CS–no US; extinction). In vertebrate subjects and several invertebrate species, a time lapse usually results in a return of the conditioned response, or spontaneous recovery. However, in land mollusks, spontaneous recovery from extinction has only recently been reported, and response recovery after latent inhibition has not been reported. In two experiments, using conditioned aversion to a food odor as a measure of learning and memory retention, we observed contingency degradation via latent inhibition (Experiment 1) and extinction (Experiment 2) in the common garden slug, Lehmannia valentiana. In both situations, the contingency degradation procedure successfully attenuated conditioned responding, and delaying testing by several days resulted in recovery of the conditioned response. This suggests that the CS–US association survived the degradation manipulation and was retained over an interval of several days.  相似文献   
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All those who compete in the sport of rowing have used the land rowing machine, Ergometer (commonly called the ‘erg’), manufactured by Concept II (Morrisville, Vermont, USA). Ergon is the Greek word for work, hence the Ergometer measures work. Rowers are commonly ranked according to their ‘erg score.’ The fault in this ranking is that the land Ergometer cannot account for many of the important technical aspects associated with rowing on the water. The goals of this project were to (1) develop a system for on-the-water measurement of work during rowing and then (2) demonstrate the potential of such a system to quantify performance and improve rowing technique. To achieve these goals, force was measured using strain gauges glued to the shaft of the rowing oar and angular displacement was measured using a potentiometer. The force and displacement measurements were sent to a microcontroller, which calculated the total work done in a particular stroke, as well as other parameters, and displayed the values to the rower. The parameters were used to evaluate the performance of three collegiate rowers on the water. The data were also used to plot force profiles, which were reviewed with each rower and the coach to illustrate the rowers’ habits and facilitate improving technique. One rower was ‘tutored’ with the device through five on-the-water practices, after which his force profiles and parameter values demonstrated significant improvement. The device not only provided a standard to which all rowers were compared on the water, but also supplied the rowers with important information on technical aspects of their strokes and pacing themselves.  相似文献   
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Integration of microfluidic devices with pressure-driven, self-powered fluid flow propulsion methods has provided a very effective solution for on-chip, droplet blood testing applications. However, precise understanding of the physical process governing fluid dynamics in polydimethylsiloxane (PDMS)-based microfluidic devices remains unclear. Here, we propose a pressure-driven diffusion model using Fick''s law and the ideal gas law, the results of which agree well with the experimental fluid dynamics observed in our vacuum pocket-assisted, self-powered microfluidic devices. Notably, this model enables us to precisely tune the flow rate by adjusting two geometrical parameters of the vacuum pocket. By linking the self-powered fluid flow propulsion method to the sedimentation, we also show that direct plasma separation from a drop of whole blood can be achieved using only a simple construction without the need for external power sources, connectors, or a complex operational procedure. Finally, the potential of the vacuum pocket, along with a removable vacuum battery to be integrated with non-PDMS microfluidic devices to drive and control the fluid flow, is demonstrated.  相似文献   
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BackgroundConsidering the potential cumulative effects of repetitive head impact (HI) exposure, we need sensitive biomarkers to track short- and long-term effects. Circulating small extracellular vesicles (sEVs) (<200 nm) traffic biological molecules throughout the body and may have diagnostic value as biomarkers for disease. The purpose of this study was to identify the microRNA (miRNA) profile in circulating sEVs derived from human plasma following repetitive HI exposure.MethodsHealthy adult (aged 18–35 years) soccer players were randomly assigned to one of 3 groups: the HI group performed 10 standing headers, the leg impact group performed 10 soccer ball trapping maneuvers over 10 min, and the control group did not participate in any soccer drills. Plasma was collected before testing and 24 h afterward, and sEVs were isolated and characterized via nanoparticle tracking analysis. Next-generation sequencing was utilized to identify candidate miRNAs isolated from sEVs, and candidate microRNAs were analyzed via quantitative polymerase chain reaction. In silico target prediction was performed using TargetScan (Version 7.0; targetscan.org) and miRWalk (http://mirwalk.umm.uni-heidelberg.de/) programs, and target validation was performed using luciferase reporter vectors with a miR-7844-5p mimic in human embryonic kidney (HEK) 293T/17 cells.ResultsPlasma sEV concentration and size were not affected across time and group following repetitive HI exposure. After 24 h, the HI read count from next-generation sequencing showed a 4-fold or greater increase in miR-92b-5p, miR-423-5p, and miR-24-3p and a 3-fold or greater decrease in miR-7844-5p, miR-144-5p, miR-221-5p, and miR-22-3p. Analysis of quantitative polymerase chain reaction revealed that leg impact did not alter the candidate miRNA levels. To our knowledge, miR-7844-5p is a previously unknown miRNA. We identified 8 miR-7844-5p mRNA targets: protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B), LIM and senescent cell antigen-like domains 1 (LIMS1), autophagy-related 12 (ATG12), microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), integrin subunit alpha-1 (ITGA1), mitogen-activated protein kinase 1 (MAPK1), glycogen synthase kinase 3β (GSK3β), and mitogen-activated protein kinase 8 (MAPK8).ConclusionCollectively, these data indicate repetitive HI exposure alters plasma sEV miRNA content, but not sEV size or number. Furthermore, for the first time we demonstrate that previously unknown miR-7844-5p targets mRNAs known to be involved in mitochondrial apoptosis, autophagy regulation, mood disorders, and neurodegenerative disease.  相似文献   
29.
The present study examined frames and second-level agenda-setting attributes used by national and local newspapers to cover the 2012 Aurora, Colorado shootings. Unlike research examining coverage of school shootings, this study examined a mass shooting that did not occur at a school. Both newspaper types published a similar number of articles—though national articles tended to be longer—and virtually stopped coverage after 18 days. While previous coverage tended to focus on shootings’ societal implications, Aurora coverage focused more on individuals involved in the time immediately surrounding the shootings. National papers focused on the gunman, while the local press tended to focus on victims. Mass shootings in general tend to be salient news items, but the present study further shows news outlets may now focus on incidents’ specifics instead of common characteristics they might share, perhaps because audiences have an existing understanding of them. The shootings were framed in terms of gun control; national newspapers used this frame more often than did local newspapers. Both newspaper types tended to discuss gun control as directly related to the Aurora shootings, rather than as a societal or continuing need. Results offer further evidence that second-level agenda-setting and framing are distinct concepts.  相似文献   
30.
The author used an archival study to explore the relationship between college counseling and retention. The cohort for this study was a college's 2006 class of full‐time, 1st‐year students (N = 429). The results of chi‐square analyses and regression analyses indicated (a) a significant difference in retention between high‐risk and low‐risk students who used counseling services (CS) and (b) that a student's risk for dropout did not vary significantly over time based on risk level or CS use.  相似文献   
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