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Agreement Among Radiographs, Fluoroscopy and Bronchoscopy in Documentation of Airway Collapse in Dogs.
BackgroundAirway collapse is a common finding in dogs with chronic cough, yet the diagnosis can be difficult to confirm without specialty equipment.HypothesisBronchoscopic documentation of tracheobronchial collapse will show better agreement with fluoroscopic imaging than with standard radiography.AnimalsForty-two dogs prospectively evaluated for chronic cough.MethodsIn this prospective study, three-view thoracic radiographs were obtained followed by fluoroscopy during tidal respiration and fluoroscopy during induction of cough. Digital images were assessed for the presence or absence of collapse at the trachea and each lobar bronchus. Bronchoscopy was performed under general anesthesia for identification of tracheobronchial collapse at each lung segment. Agreement of imaging tests with bronchoscopy was evaluated along with sensitivity and specificity of imaging modalities as compared to bronchoscopy.ResultsAirway collapse was identified in 41/42 dogs via 1 or more testing modalities. Percent agreement between pairs of tests varied between 49 and 87% with poor-moderate agreement at most bronchial sites. Sensitivity for the detection of bronchoscopically identified collapse was highest for radiography at the trachea, left lobar bronchi, and the right middle bronchus, although specificity was relatively low. Detection of airway collapse was increased when fluoroscopy was performed after induction of cough compared to during tidal respiration.ConclusionsRadiography and fluoroscopy are complementary imaging techniques useful in the documentation of bronchial collapse in dogs. Confirming the presence or absence of tracheal or bronchial collapse can require multiple imaging modalities as well as bronchoscopy
Sharing data from clinical trials: the rationale for a controlled access approach.
The move towards increased transparency around clinical trials is welcome. Much focus has been on under-reporting of trials and access to individual patient data to allow independent verification of findings. There are many other good reasons for data sharing from clinical trials. We describe some key issues in data sharing, including the challenges of open access to data. These include issues in consent and disclosure; risks in identification, including self-identification; risks in distorting data to prevent self-identification; and risks in analysis. These risks have led us to develop a controlled access policy, which safeguards the rights of patients entered in our trials, guards the intellectual property rights of the original researchers who designed the trial and collected the data, provides a barrier against unnecessary duplication, and ensures that researchers have the necessary resources and skills to analyse the data
Self-esteem and self-efficacy in the status attainment process and the multigenerational transmission of advantage
Despite considerable evidence of the importance of self-esteem and self-efficacy for agentic, goal-oriented behavior, little attention has been directed to these psychological dimensions in the status attainment literature. The present research uses data from the longitudinal, three-generation Youth Development Study (NāÆ=āÆ422 three-generation triads) to examine the extent to which adolescent self-esteem and economic self-efficacy affect adult educational and income attainment, and whether these psychological resources are transmitted from one generation to the next, accumulating advantage across generations. We present evidence indicating that both self-esteem and economic self-efficacy are implicated in the attainment process. Adolescent economic self-efficacy had a direct positive effect on adult educational attainment and an indirect effect through educational plans. The influence of self-esteem on adult educational attainment was entirely indirect, through school achievement. We also find evidence that economic self-efficacy was transmitted from parents to children. We conclude that future research should more broadly consider psychological resources in attainment processes from a longitudinal multigenerational perspective
FREE-SURFACE ADJUSTMENT AND TOPOGRAPHIC WAVES IN COASTAL CURRENTS
The adjustment of rotating free-surface flow over a step-like escarpment abutting a vertical wall is discussed in the context of the shallow-water equations. The problem is simplified by considering an escarpment of small fractional depth, so that on the slow topographic timescale the initial, fast PoincarƩ and Kelvin wave adjustment of the free surface is effectively instantaneous, and further simplified by considering the surface displacement to be small compared with the escarpment height so that particle velocities are negligible during the topographic adjustment. Direct solution of the resulting linear system is not straightforward as arbitrarily small-scale motions are generated at sufficiently large times. The problem is reduced by a Green's function technique to one spatial dimension and the wall boundary layers resolved by introducing a scaling based on previously obtained limit solutions. Solutions verify the information-propagation arguments of Johnson (1985) and Gill et al. (1986) and also show interchange of fluid across the escarpment as eddies formed as the current crosses the step travel along the step with shallow water to their right. The pattern of evolution of the system is independent of the direction of the flow, depending solely on the sign of the topographic step. If the escarpment is such that topographic waves travel away from the wall, then a tongue of fluid moves outward along the step: the initial jet along the wall is diverted to flow parallel to, rather than across, the step. If waves travel towards the wall then the current is pinched into the wall and fluid crosses the escarpment in a thinning jet
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Brain Mechanisms of Reality Monitoring
Reality monitoring processes are necessary for discriminating between internally generated information and information that originated in the outside world. They help us to identify our thoughts, feelings, and imaginations, and to distinguish them from events we may have experienced or have been told about by someone else. Reality monitoring errors range from confusions between real and imagined experiences, that are byproducts of normal cognition, to symptoms of mental illness such as hallucinations. Recent advances support an emerging neurocognitive characterization of reality monitoring that provides insights into its underlying operating principles and neural mechanisms, the differing ways in which impairment may occur in health and disease, and the potential for rehabilitation strategies to be devised that might help those who experience clinically significant reality monitoring disruption.Preparation of this article was supported by a James S. McDonnell Foundation Scholar Award to J.S.S., and by the University of Cambridge Behavioural and Clinical Neuroscience Institute, funded by a joint award from the Medical Research Council and the Wellcome Trust
Paying the Guard: An Entry-Guard-Based Payment System for Tor
When choosing the three relays that compose a circuit, Tor selects the first hop among a restricted number of relays called entry guards, pre-selected by the user himself. The reduced number of entry guards, that until recently was fixed to three, helps in mitigating the effects of several traffic analysis attacks. However, recent literature indicates that the number should be further reduced, and the time during which the user keeps the relays as guards increased. Therefore, developers of Tor recently proposed selecting only one entry guard, which is to be used by the user for all circuits and for a prolonged period of time (nine months). While this design choice was made to increase the security of the protocol, it also opens an unprecedented opportunity for a market mechanism where relays get paid for traffic by the users. In this paper, we propose to use the entry guard as the point-of-sale: users subscribe to their entry guard of choice, and deposit an amount that will be used for paying for the circuits. From the entry guard, income is then distributed to the other relays included in circuits through an inter-relay accounting system. While the user may pay the entry guard using BitCoins, or any other anonymous payment system, the relays exchange I Owe You (IOU) certificates during communication, and settle their balances only at synchronized, later points in time. This novel deferred payment approach overcomes the weaknesses of the previously proposed Tor payment mechanisms: we separate the userās payment from the inter-relay payments, and we effectively unlink both from the chosen path, thus preserving the secrecy of the circuit
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The rememberingāimagining system
Remembering and imagining are intricately related, particularly in imagining the future: episodic future thinking. It is proposed that remembering the recent past and imagining the near future take place in what we term the rememberingāimagining system. The rememberingāimagining system renders recently formed episodic memories and episodic imagined near-future events highly accessible. We suggest that this serves the purpose of integrating past, current, and future goal-related activities. When the rememberingāimagining system is compromised, following brain damage and in psychological illnesses, the future cannot be effectively imagined and episodic future thinking may become dominated by dysfunctional images of the future
Association between Plasma Antibody Response and Protection in Rainbow Trout Oncorhynchus mykiss Immersion Vaccinated against Yersinia ruckeri
A key hallmark of the vertebrate adaptive immune system is the generation of antigen-specific antibodies from B cells. Fish are the most primitive gnathostomes (jawed vertebrates) possessing an adaptive immune system. Vaccination of rainbow trout against enteric redmouth disease (ERM) by immersion in Yersinia ruckeri bacterin confers a high degree of protection to the fish. The immune mechanisms responsible for protection may comprise both cellular and humoral elements but the role of specific immunoglobulins in this system has been questioned and not previously described. The present study demonstrates significant increase in plasma antibody titers following immersion vaccination and significantly reduced mortality during Y. ruckeri challenge
Taken by strum: ukuleles and participatory music-making in Hamilton, Aotearoa/New Zealand
Ethnographic study of ukulele playing in Hamilton, N
Why alternative teenagers self-harm: exploring the link between non-suicidal self-injury, attempted suicide and adolescent identity
Background:
The term āself-harmā encompasses both attempted suicide and non-suicidal self-injury (NSSI). Specific adolescent subpopulations such as ethnic or sexual minorities, and more controversially, those who identify as āAlternativeā (Goth, Emo) have been proposed as being more likely to self-harm, while other groups such as āJocksā are linked with protective coping behaviours (for example exercise). NSSI has autonomic (it reduces negative emotions) and social (it communicates distress or facilitates group ābondingā) functions. This study explores the links between such aspects of self-harm, primarily NSSI, and youth subculture.<p></p>
Methods:
An anonymous survey was carried out of 452 15 year old German school students. Measures included: identification with different youth cultures, i.e. Alternative (Goth, Emo, Punk), Nerd (academic) or Jock (athletic); social background, e.g. socioeconomic status; and experience of victimisation. Self-harm (suicide and NSSI) was assessed using Self-harm Behavior Questionnaire and the Functional Assessment of Self-Mutilation (FASM).<p></p>
Results:
An āAlternativeā identity was directly (rāāā0.3) and a āJockā identity inversely (rāāā-0.1) correlated with self-harm. āAlternativeā teenagers self-injured more frequently (NSSI 45.5% vs. 18.8%), repeatedly self-injured, and were 4ā8 times more likely to attempt suicide (even after adjusting for social background) than their non-Alternative peers. They were also more likely to self-injure for autonomic, communicative and social reasons than other adolescents.<p></p>
Conclusions:
About half of āAlternativeā adolescentsā self-injure, primarily to regulate emotions and communicate distress. However, a minority self-injure to reinforce their group identity, i.e. āTo feel more a part of a groupā
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