305 resultados para Vision Disorders
Resumo:
Aim: As molecular and cytogenetic testing becomes increasingly sophisticated, more individuals are being diagnosed with rare chromosome disorders. Yet despite a burgeoning knowledge about biomedical aspects, little is known about implications for psychosocial development. The scant literature gives a general impression of deficits and adverse developmental outcomes. Method: Developmental data were obtained from two 16 year olds diagnosed with a rare chromosome disorder – a girl with 8p23.1 and a boy with 16q11.2q12.1. Measures of intellectual ability, academic achievement, and other aspects of functioning were administered at multiple time points from early childhood to adolescence. Results: Both adolescents experienced initial delays in motor and language development. Although the girl’s intelligence is assessed as being in the average range, she experiences difficulties with motor planning, spelling and writing. The boy has been diagnosed with a mild intellectual disability and demonstrates mild autistic features. Conclusions: The two case descriptions are in marked contrast to the published literature about these two chromosome anomalies. Both adolescents are developing much more positively than would be expected on the basis of the grim predictions of their paediatricians and the negative reports in the literature. It is concluded that, for most rare chromosome disorders, the range of possible developmental outcomes is currently unknown.
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This paper presents the application of a monocular visual SLAMon a fixed-wing small Unmanned Aerial System (sUAS) capable of simultaneous estimation of aircraft pose and scene structure. We demonstrate the robustness of unconstrained vision alone in producing reliable pose estimates of a sUAS, at altitude. It is ultimately capable of online state estimation feedback for aircraft control and next-best-view estimation for complete map coverage without the use of additional sensors.We explore some of the challenges of visual SLAM from a sUAS including dealing with planar structure, distant scenes and noisy observations. The developed techniques are applied on vision data gathered from a fast-moving fixed-wing radio control aircraft flown over a 1×1km rural area at an altitude of 20-100m.We present both raw Structure from Motion results and a SLAM solution that includes FAB-MAP based loop-closures and graph-optimised pose. Timing information is also presented to demonstrate near online capabilities. We compare the accuracy of the 6-DOF pose estimates to an off-the-shelfGPS aided INS over a 1.7kmtrajectory.We also present output 3D reconstructions of the observed scene structure and texture that demonstrates future applications in autonomous monitoring and surveying.
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Butterflies and primates are interesting for comparative color vision studies, because both have evolved middle- (M) and long-wavelength- (L) sensitive photopigments with overlapping absorbance spectrum maxima (lambda(max) values). Although positive selection is important for the maintenance of spectral variation within the primate pigments, it remains an open question whether it contributes similarly to the diversification of butterfly pigments. To examine this issue, we performed epimicrospectrophotometry on the eyes of five Limenitis butterfly species and found a 31-nm range of variation in the lambda(max) values of the L-sensitive photopigments (514-545 nm). We cloned partial Limenitis L opsin gene sequences and found a significant excess of replacement substitutions relative to polymorphisms among species. Mapping of these L photopigment lambda(max) values onto a phylogeny revealed two instances within Lepidoptera of convergently evolved L photopigment lineages whose lambda(max) values were blue-shifted. A codon-based maximum-likelihood analysis indicated that, associated with the two blue spectral shifts, four amino acid sites (Ile17Met, Ala64Ser, Asn70Ser, and Ser137Ala) have evolved substitutions in parallel and exhibit significant d(N)/d(S) >1. Homology modeling of the full-length Limenitis arthemis astyanax L opsin placed all four substitutions within the chromophore-binding pocket. Strikingly, the Ser137Ala substitution is in the same position as a site that in primates is responsible for a 5- to 7-nm blue spectral shift. Our data show that some of the same amino acid sites are under positive selection in the photopigments of both butterflies and primates, spanning an evolutionary distance >500 million years.
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The authors present a qualitative and quantitative comparison of various similarity measures that form the kernel of common area-based stereo-matching systems. The authors compare classical difference and correlation measures as well as nonparametric measures based on the rank and census transforms for a number of outdoor images. For robotic applications, important considerations include robustness to image defects such as intensity variation and noise, the number of false matches, and computational complexity. In the absence of ground truth data, the authors compare the matching techniques based on the percentage of matches that pass the left-right consistency test. The authors also evaluate the discriminatory power of several match validity measures that are reported in the literature for eliminating false matches and for estimating match confidence. For guidance applications, it is essential to have and estimate of confidence in the three-dimensional points generated by stereo vision. Finally, a new validity measure, the rank constraint, is introduced that is capable of resolving ambiguous matches for rank transform-based matching.
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Objective: Substance use is common in first-episode psychosis, and complicates the accurate diagnosis and treatment of the disorder. The differentiation of substance-induced psychotic disorders (SIPD) from primary psychotic disorders (PPD) is particularly challenging. This cross-sectional study compares the clinical, substance use and functional characteristics of substance using first episode psychosis patients diagnosed with a SIPD and PPD. Method: Participants were 61 young people (15-24 years) admitted to a psychiatric inpatient service with first episode psychosis, reporting substance use in the past month. Diagnosis was determined using the Psychiatric Research Interview for DSM-IV Substance and Mental disorders (PRISM-IV). Measures of clinical (severity of psychotic symptoms, level of insight, history of trauma), substance use (frequency/quantity, severity) and social and occupational functioning were also administered. Results: The PRISM-IV differentially diagnosed 56% of first episode patients with a SIPD and 44% with a PPD. Those with a SIPD had higher rates of substance use and disorders, higher levels of insight, were more likely to have a forensic and trauma history and had more severe hostility and anxious symptoms than those with a PPD. Logistic regression analysis indicated a family history of psychosis, trauma history and current cannabis dependence were the strongest predictors of a SIPD. Almost 80% of diagnostic predictions of a SIPD were accurate using this model. Conclusions: This clinical profile of SIPD could help to facilitate the accurate diagnosis and treatment of SIPD versus PPD in young people with first episode psychosis admitted to an inpatient psychiatric service.
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Objective: Excessive alcohol consumption is common among people with psychotic disorders. While there is an extensive literature on the efficacy of psychological treatments for excessive drinking, few studies have examined interventions addressing this issue among people with psychotic disorders. Method: Systematic searches in PubMed and PsycINFO were conducted to identify randomized controlled trials comparing manual guided psychological interventions for excessive alcohol consumption among individuals with psychotic disorders. Of the 429 articles identified, 7 met inclusion criteria. Data were extracted from each study regarding study sample characteristics, design, results, clinical significance of alcohol consumption results, and methodological limitations. Results: Assessment interviews, brief motivational interventions and lengthier cognitive behavior therapy have been associated with reductions in alcohol consumption among people with psychosis. While brief interventions (i.e., 1-2 sessions) were generally as effective as longer duration psychological interventions (i.e., 10 session) for reducing alcohol consumption, longer interventions provided additional benefits for depression, functioning and other alcohol outcomes. Conclusion: Excessive alcohol consumption among people with psychotic disorders is responsive to psychological interventions. It is imperative that such approaches are integrated within standard care for people with psychosis.
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"The World Health Organisation has identified physical inactivity as the fourth leading effective cause of death globally. The burden of physical inactivity will increase as the population ages. In addition to increased risk or mortality, prior research has indicated older adults with chronic musculoskeletal conditions are likely to face increased morbidity and poorer prognoses if they are physically inactive. There is currently a scarcity of empirical research describing the physical activity profile of older adults with chronic musculoskeletal disorders. The aim of this investigation was to describe the self-reported physical activity profile and body mass index (BMI) profile of a sample of older adults with chronic musculoskeletal disorders accessing outpatient hospital services."--publisher website
Resumo:
Background: Comorbidity of mental disorders and substance use continues to be a major problem. To inform the development of more effective interventions for these co-existing disorders, this paper aimed to determine if there are clear variations in the reasons for tobacco, alcohol or cannabis use across people with different mental disorders. Methods: Data from five randomized controlled trials on co-existing disorders that measured reasons for tobacco, alcohol or cannabis use using the Drug Use Motives Questionnaire, Reasons for Smoking Questionnaire or via free response are reported and combined. Two studies involved participants with depression, two involved participants with a psychotic disorder and one involved participants with a range of mental disorders. A series of logistic regressions were conducted to examine differences in reasons for tobacco, alcohol or cannabis use and to compare these reasons between people with psychotic disorders or depression. Results: Participants had a mean age of 38 (SD=12) and just over half (60%) were male. Forty-six percent of participants had a psychotic disorder and 54% experienced depression. Data from 976 participants across the five studies were included in the analyses. Tobacco and alcohol were primarily used to cope, while cannabis was primarily used for pleasure. People with psychotic disorders were more likely than people with depression to use tobacco for coping, pleasure and illness motives. People with depression, in contrast, were more likely to use alcohol for these reasons and social reasons. Conclusions: It may be important to tailor interventions for co-existing mental disorders and substance use by substance type and type of mental disorder. For example, interventions might be improved by including alternative coping strategies to tobacco and/or alcohol use, by addressing the social role of alcohol and by helping people with mental disorders using cannabis to gain pleasure from their lives in other ways.
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There is growing and converging evidence that cannabis may be a major risk factor in people with psychotic disorders and prodromal psychotic symptoms. The lack of available pharmacological treatments for cannabis use indicates that psychological interventions should be a high priority, especially among people with psychotic disorders. However, there have been few randomised controlled trials (RCTs) of psychological interventions among this group. In the present study we critically overview RCTs of psychological and pharmacologic interventions among people with psychotic disorders, giving particular attention to those studies which report cannabis use outcomes. We then review data regarding treatment preferences among this group. RCTs of interventions within "real world" mental health systems among adults with severe mental disorders suggest that cannabis use is amenable to treatment in real world settings among people with psychotic disorders. RCTs of manual guided interventions among cannabis users indicate that while brief interventions are associated with reductions in cannabis use, longer interventions may be more effective. Additionally, RCTs reviewed suggest treatment with antipsychotic medication is not associated with a worsening of cannabis cravings or use and may be beneficial. The development of cannabinoid agonist medication may be an effective strategy for cannabis dependence and suitable for people with psychotic disorders. The development of cannabis use interventions for people with psychotic disorders should also consider patients' treatment preferences. Initial results indicate face-to-face interventions focussed on cannabis use may be preferred. Further research investigating the treatment preferences of people with psychotic disorders using cannabis is needed.