1,223 research outputs found
Description and calibration of the Langley unitary plan wind tunnel
The two test sections of the Langley Unitary Plan Wind Tunnel were calibrated over the operating Mach number range from 1.47 to 4.63. The results of the calibration are presented along with a a description of the facility and its operational capability. The calibrations include Mach number and flow angularity distributions in both test sections at selected Mach numbers and tunnel stagnation pressures. Calibration data are also presented on turbulence, test-section boundary layer characteristics, moisture effects, blockage, and stagnation-temperature distributions. The facility is described in detail including dimensions and capacities where appropriate, and example of special test capabilities are presented. The operating parameters are fully defined and the power consumption characteristics are discussed
Spectral Characterization of Longitudinal Coupled-bunch instabilities at the Advanced Light Source
Surprisingly Little Population Genetic Structure In A Fungus-Associated Beetle Despite Its Exploitation Of Multiple Hosts
In heterogeneous environments, landscape features directly affect the structure of genetic variation among populations by functioning as barriers to gene flow. Resource-associated population genetic structure, in which populations that use different resources (e.g., host plants) are genetically distinct, is a well-studied example of how environmental heterogeneity structures populations. However, the pattern that emerges in a given landscape should depend on its particular combination of resources. If resources constitute barriers to gene flow, population differentiation should be lowest in homogeneous landscapes, and highest where resources exist in equal proportions. In this study, we tested whether host community diversity affects population genetic structure in a beetle (Bolitotherus cornutus) that exploits three sympatric host fungi. We collected B.cornutus from plots containing the three host fungi in different proportions and quantified population genetic structure in each plot using a panel of microsatellite loci. We found no relationship between host community diversity and population differentiation in this species; however, we also found no evidence of resource-associated differentiation, suggesting that host fungi are not substantial barriers to gene flow. Moreover, we detected no genetic differentiation among B.cornutus populations separated by several kilometers, even though a previous study demonstrated moderate genetic structure on the scale of a few hundred meters. Although we found no effect of community diversity on population genetic structure in this study, the role of host communities in the structuring of genetic variation in heterogeneous landscapes should be further explored in a species that exhibits resource-associated population genetic structure
Editorial : Predictive mechanisms in action, perception, cognition, and clinical disorders
Acknowledgments The authors would like to acknowledge their funding sources (NIH F32 MH117933 to AD, Alon Fellowship to LR).Peer reviewedPublisher PD
Illusions and Delusions: Relating Experimentally-Induced False Memories to Anomalous Experiences and Ideas
The salience hypothesis of psychosis rests on a simple but profound observation that subtle alterations in the way that we perceive and experience stimuli have important consequences for how important these stimuli become for us, how much they draw our attention, how they embed themselves in our memory and, ultimately, how they shape our beliefs. We put forward the idea that a classical memory illusion – the Deese–Roediger–McDermott (DRM) effect – offers a useful way of exploring processes related to such aberrant belief formation. The illusion occurs when, as a consequence of its relationship to previous stimuli, a stimulus that has not previously been presented is falsely remembered. Such illusory familiarity is thought to be generated by the surprising fluency with which the stimulus is processed. In this respect, the illusion relates directly to the salience hypothesis and may share common cognitive underpinnings with aberrations of perception and attribution that are found in psychosis. In this paper, we explore the theoretical importance of this experimentally-induced illusion in relation to the salience model of psychosis. We present data showing that, in healthy volunteers, the illusion relates directly to self reported anomalies of experience and magical thinking. We discuss this finding in terms of the salience hypothesis and of a broader Bayesian framework of perception and cognition which emphasizes the salience both of predictable and unpredictable experiences
Comparison of pharmacist and public views and experiences of community pharmacy medicines-related services in England
Background: Services provided by community pharmacists designed to support people using medicines are increasing. In England, two national services exist: Medicine Use Reviews (MUR) and New Medicines Service (NMS). Very few studies have been conducted seeking views of the public, rather than service users, on willingness to use these services or expectations of these services, or determined whether views align with pharmacist perceptions.
Objective: To compare the perceptions of pharmacists and the general public on medicines-related services, particularly MUR and NMS services.
Methods: Two parallel surveys were conducted in one area of England: one involved the general public and was administered using a street survey, and the other was a postal survey of community pharmacists. Similar questionnaires were used, seeking views of services, awareness, reasons for using services, and perceived benefits.
Results: Response rates were 47.2% (1,000/2,012 approached) for the public and 40.8% (341/836) for pharmacists. Few people had experienced a discussion in a private consultation room or were aware of the two formal services, although their willingness to use them was high. Pharmacists estimated time spent on service provision as 10 minutes for MUR and 12 minutes for NMS, which aligned with acceptability to both pharmacists and the public. Pharmacists underestimated the willingness of the public to wait for an informal discussion or to make appointments for formal services. Both pharmacists and the public had high expectations that services would be beneficial in terms of increasing knowledge and understanding, but public expectations and experiences of services helping to sort out problems fell well below pharmacists’ perceptions. People who had experienced a pharmacy service had different perceptions of pharmacists.
Conclusion: Views differed regarding why people use services and key aspects of service delivery. For services to improve, the pharmacy profession needs a better awareness of what the public, especially those with potential to benefit from services, view as acceptable and desirable
An insight into light as a chronobiological therapy in affective disorders
The field of chronobiology has vastly expanded over the past few decades, bringing together research from the fields of circadian rhythms and sleep. The importance of the environmental day–night cycle on our health is becoming increasingly evident as we evolve into a 24-hour society. Reducing or changing sleep times against our natural instincts to rest at night has a detrimental impact on our well-being. The mammalian circadian clock, termed "the suprachiasmatic nucleus", is responsible for synchronizing our behavioral and physiological outputs to the environment. It utilizes light transcoded by specialized retinal photoreceptors as its cue to set internal rhythms to be in phase with the light–dark cycle. Misalignment of these outputs results in symptoms such as altered/disturbed sleep patterns, changes in mood, and physical and mental exhaustion – symptoms shared by many affective clinical disorders. Key links to circadian abnormalities have been found in a number of disorders, such as seasonal affective disorder, nonseasonal depression, and bipolar affective disorder. Furthermore, therapies developed through chronobiological research have been shown to be beneficial in the treatment of these conditions. In this article, we discuss the impact of circadian research on the management of affective disorders, giving evidence of how a misaligned circadian system may be a contributor to the symptoms of depression and how moderating circadian rhythms with light therapy benefits patients
Medicine-related services in community pharmacy: public preferences for pharmacy attributes and promotional methods and comparison with pharmacists' perceptions
Background: Public awareness of pharmacy services designed to support use of medicines is low, yet little is known about how the public view promotion of these services or their preferences for the attributes of pharmacies from which they would like to receive them.
Objective: To compare the public’s preferred attributes of pharmacies and methods for promoting medicine-related services with community pharmacists’ perceptions of their customers’ views.
Method: Parallel surveys of the general public, using a street survey, and community pharmacists, via a postal survey in South East England.
Results: Response rates were: public 47.2% (1000/2012) and pharmacists 40.8% (341/836) respectively. Pharmacists’ perceptions of customer preferences for using the same pharmacy, independent ownership and personal knowledge of the pharmacist were higher than actual public preferences. More pharmacists also thought approachability and previous good service would be important than the public. The public’s desires for long opening hours and for a pharmacy with a good relationship with their doctor’s surgery was higher than pharmacists believed. The majority of the public prefer not to interrupt a pharmacist busy in the dispensary, which was not perceived by pharmacists as a factor. Pharmacists’ perceptions aligned more with the preferences of regular medicines users and frequent pharmacy users. Both groups viewed direct recommendation as the most effective approach for promoting pharmacy services, particularly by doctors and pharmacy staff. Pharmacists’ expectations of the effectiveness of posters and mass media methods were much higher than those of the public.
Conclusions: Pharmacists and pharmacy owners must ensure good relationships with local medical practices to enable them to maximise opportunities for using the promotional methods judged most effective in encouraging use of medicine-related services. Staff must be approachable and enable access to pharmacists ensuring perceptions of pharmacist busyness are not a deterrent
Global late Quaternary megafauna extinctions linked to humans, not climate change
The late Quaternary megafauna extinction was a severe global-scale event. Two factors, climate change and modern humans, have received broad support as the primary drivers, but their absolute and relative importance remains controversial. To date, focus has been on the extinction chronology of individual or small groups of species, specific geographical regions or macroscale studies at very coarse geographical and taxonomic resolution, limiting the possibility of adequately testing the proposed hypotheses. We present, to our knowledge, the first global analysis of this extinction based on comprehensive country-level data on the geographical distribution of all large mammal species (more than or equal to 10 kg) that have gone globally or continentally extinct between the beginning of the Last Interglacial at 132 000 years BP and the late Holocene 1000 years BP, testing the relative roles played by glacial–interglacial climate change and humans. We show that the severity of extinction is strongly tied to hominin palaeobiogeography, with at most a weak, Eurasia-specific link to climate change. This first species-level macroscale analysis at relatively high geographical resolution provides strong support for modern humans as the primary driver of the worldwide megafauna losses during the late Quaternary
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