4,196 research outputs found
The Effect of Focal Damage to the Right Medial Posterior Cerebellum on Word and Sentence Comprehension and Production
Functional imaging studies of neurologically intact adults have demonstrated that the
right posterior cerebellum is activated during verb generation, semantic processing,
sentence processing, and verbal fluency. Studies of patients with cerebellar damage
converge to show that the cerebellum supports sentence processing and verbal
fluency. However, to date there are no patient studies that investigated the specific
importance of the right posterior cerebellum in language processing, because: (i)
case studies presented patients with lesions affecting the anterior cerebellum (with or
without damage to the posterior cerebellum), and (ii) group studies combined patients
with lesions to different cerebellar regions, without specifically reporting the effects
of right posterior cerebellar damage. Here we investigated whether damage to the
right posterior cerebellum is critical for sentence processing and verbal fluency in four
patients with focal stroke damage to different parts of the right posterior cerebellum (all
involving Crus II, and lobules VII and VIII). We examined detailed lesion location by going
beyond common anatomical definitions of cerebellar anatomy (i.e., according to lobules
or vascular territory), and employed a recently proposed functional parcellation of the
cerebellum. All four patients experienced language difficulties that persisted for at least a
month after stroke but three performed in the normal range within a year. In contrast, one
patient with more damage to lobule IX than the other patients had profound long-lasting
impairments in the comprehension and repetition of sentences, and the production of
spoken sentences during picture description. Spoken and written word comprehension
and visual recognition memory were also impaired, however, verbal fluency was within
the normal range, together with object naming, visual perception and verbal shortterm
memory. This is the first study to show that focal damage to the right posterior
cerebellum leads to language difficulties after stroke; and that processing impairments
persisted in the case with most damage to lobule IX. We discuss these results in
relation to current theories of cerebellar contribution to language processing. Overall, our study highlights the need for longitudinal studies of language function in patients
with focal damage to different cerebellar regions, with functional imaging to understand
the mechanisms that support recovery
Mobile Communication Signatures of Unemployment
The mapping of populations socio-economic well-being is highly constrained by
the logistics of censuses and surveys. Consequently, spatially detailed changes
across scales of days, weeks, or months, or even year to year, are difficult to
assess; thus the speed of which policies can be designed and evaluated is
limited. However, recent studies have shown the value of mobile phone data as
an enabling methodology for demographic modeling and measurement. In this work,
we investigate whether indicators extracted from mobile phone usage can reveal
information about the socio-economical status of microregions such as districts
(i.e., average spatial resolution < 2.7km). For this we examine anonymized
mobile phone metadata combined with beneficiaries records from unemployment
benefit program. We find that aggregated activity, social, and mobility
patterns strongly correlate with unemployment. Furthermore, we construct a
simple model to produce accurate reconstruction of district level unemployment
from their mobile communication patterns alone. Our results suggest that
reliable and cost-effective economical indicators could be built based on
passively collected and anonymized mobile phone data. With similar data being
collected every day by telecommunication services across the world,
survey-based methods of measuring community socioeconomic status could
potentially be augmented or replaced by such passive sensing methods in the
future
Endoscopists attitudes on the publication of "quality" data for endoscopic procedures: a cross-sectional survey
<p>Abstract</p> <p>Background</p> <p>Whilst the public now have access to mortality & morbidity data for cardiothoracic surgeons, such "quality" data for endoscopy are not generally available. We studied endoscopists' attitudes to and the practicality of this data being published.</p> <p>Methods</p> <p>We sent a questionnaire to all consultant gastrointestinal (GI) surgeons, physicians and medical GI specialist registrars in the Northern region who currently perform GI endoscopic procedures (n = 132). We recorded endoscopist demographics, experience and current data collection practice. We also assessed the acceptability and utility of nine items describing endoscopic "quality" (e.g. mortality, complication & completion rates).</p> <p>Results</p> <p>103 (78%) doctors responded of whom 79 were consultants (77%). 61 (59%) respondents were physicians. 77 (75%) collect any "quality" data. The most frequently collected item was colonoscopic completion rate. Data were most commonly collected for appraisal, audit or clinical governance. The majority of doctors (54%) kept these data only available to themselves, and just one allowed the public to access this. The most acceptable data item was annual number of endoscopies and the least was crude upper GI bleeding mortality. Surgeons rated information less acceptable and less useful than physicians. Acceptability and utility scores were not related to gender, length of experience or current activity levels. Only two respondents thought all items totally unacceptable and useless.</p> <p>Conclusion</p> <p>The majority of endoscopists currently collect "quality" data for their practice although these are not widely available. The endoscopists in this study consider the publication of their outcome data to be "fairly unacceptable/not very useful" to "neutral" (score 2–3). If these data were made available to patients, consideration must be given to both its value and its acceptability.</p
Right cerebral motor areas that support accurate speech production following damage to cerebellar speech areas
Specific regions of the cerebellum are activated when neurologically intact adults speak, and cerebellar damage can impair speech production early after stroke, but how the brain supports accurate speech production years after cerebellar damage remains unknown. We investigated this in patients with cerebellar lesions affecting regions that are normally recruited during speech production. Functional MRI activation in these patients, measured during various single word production tasks, was compared to that of neurologically intact controls, and patient controls with lesions that spared the cerebellar speech production regions. Our analyses revealed that, during a range of speech production tasks, patients with damage to cerebellar speech production regions had greater activation in the right dorsal premotor cortex (r-PMd) and right supplementary motor area (r-SMA) compared to neurologically intact controls. The loci of increased activation in cerebral motor speech areas motivate future studies to delineate the functional contributions of different parts of the speech production network, and test whether non-invasive stimulation to r-PMd and r-SMA facilitates speech recovery after cerebellar stroke
Why Are Male Social Relationships Complex in the Doubtful Sound Bottlenose Dolphin Population?
Copyright 2008 Elsevier B.V., All rights reserved.Peer reviewedPublisher PD
FindFoci: a focus detection algorithm with automated parameter training that closely matches human assignments, reduces human inconsistencies and increases speed of analysis
Accurate and reproducible quantification of the accumulation of proteins into foci in cells is essential for data interpretation and for biological inferences. To improve reproducibility, much emphasis has been placed on the preparation of samples, but less attention has been given to reporting and standardizing the quantification of foci. The current standard to quantitate foci in open-source software is to manually determine a range of parameters based on the outcome of one or a few representative images and then apply the parameter combination to the analysis of a larger dataset. Here, we demonstrate the power and utility of using machine learning to train a new algorithm (FindFoci) to determine optimal parameters. FindFoci closely matches human assignments and allows rapid automated exploration of parameter space. Thus, individuals can train the algorithm to mirror their own assignments and then automate focus counting using the same parameters across a large number of images. Using the training algorithm to match human assignments of foci, we demonstrate that applying an optimal parameter combination from a single image is not broadly applicable to analysis of other images scored by the same experimenter or by other experimenters. Our analysis thus reveals wide variation in human assignment of foci and their quantification. To overcome this, we developed training on multiple images, which reduces the inconsistency of using a single or a few images to set parameters for focus detection. FindFoci is provided as an open-source plugin for ImageJ
Effects of gestational age at birth on cognitive performance : a function of cognitive workload demands
Objective: Cognitive deficits have been inconsistently described for late or moderately preterm children but are consistently found in very preterm children. This study investigates the association between cognitive workload demands of tasks and cognitive performance in relation to gestational age at birth.
Methods: Data were collected as part of a prospective geographically defined whole-population study of neonatal at-risk children in Southern Bavaria. At 8;5 years, n = 1326 children (gestation range: 23–41 weeks) were assessed with the K-ABC and a Mathematics Test.
Results: Cognitive scores of preterm children decreased as cognitive workload demands of tasks increased. The relationship between gestation and task workload was curvilinear and more pronounced the higher the cognitive workload: GA2 (quadratic term) on low cognitive workload: R2 = .02, p<0.001; moderate cognitive workload: R2 = .09, p<0.001; and high cognitive workload tasks: R2 = .14, p<0.001. Specifically, disproportionally lower scores were found for very (<32 weeks gestation) and moderately (32–33 weeks gestation) preterm children the higher the cognitive workload of the tasks. Early biological factors such as gestation and neonatal complications explained more of the variance in high (12.5%) compared with moderate (8.1%) and low cognitive workload tasks (1.7%).
Conclusions: The cognitive workload model may help to explain variations of findings on the relationship of gestational age with cognitive performance in the literature. The findings have implications for routine cognitive follow-up, educational intervention, and basic research into neuro-plasticity and brain reorganization after preterm birth
Environmental Health Disparities: A Framework Integrating Psychosocial and Environmental Concepts
Although it is often acknowledged that social and environmental factors interact to produce racial and ethnic environmental health disparities, it is still unclear how this occurs. Despite continued controversy, the environmental justice movement has provided some insight by suggesting that disadvantaged communities face greater likelihood of exposure to ambient hazards. The exposure–disease paradigm has long suggested that differential “vulnerability” may modify the effects of toxicants on biological systems. However, relatively little work has been done to specify whether racial and ethnic minorities may have greater vulnerability than do majority populations and, further, what these vulnerabilities may be. We suggest that psychosocial stress may be the vulnerability factor that links social conditions with environmental hazards. Psychosocial stress can lead to acute and chronic changes in the functioning of body systems (e.g., immune) and also lead directly to illness. In this article we present a multidisciplinary framework integrating these ideas. We also argue that residential segregation leads to differential experiences of community stress, exposure to pollutants, and access to community resources. When not counterbalanced by resources, stressors may lead to heightened vulnerability to environmental hazards
Labrador retrievers under primary veterinary care in the UK: demography, mortality and disorders
Abstract Background Labrador retrievers are reportedly predisposed to many disorders but accurate prevalence information relating to the general population are lacking. This study aimed to describe demography, mortality and commonly recorded diseases in Labrador retrievers under UK veterinary care. Methods The VetCompass™ programme collects electronic patient record data on dogs attending UK primary-care veterinary practices. Demographic analysis covered all33,320 Labrador retrievers in the VetCompass™ database under veterinary care during 2013 while disorder and mortality data were extracted from a random sample of 2074 (6.2%) of these dogs. Results Of the Labrador retrievers with information available, 15,427 (46.4%) were female and 15,252 (53.6%) were male. Females were more likely to be neutered than males (59.7% versus 54.8%, P < 0.001). The overall mean adult bodyweight was 33.0 kg (SD 6.1). Adult males were heavier (35.2 kg, SD 5.9 kg) than adult females (30.4 kg, SD 5.2 kg) (P < 0.001). The median longevity of Labrador retrievers overall was 12.0 years (IQR 9.9–13.8, range 0.0–16.0). The most common recorded colours were black (44.6%), yellow (27.8%) and liver/chocolate (reported from hereon as chocolate) (23.8%). The median longevity of non-chocolate coloured dogs (n = 139, 12.1 years, IQR 10.2–13.9, range 0.0–16.0) was longer than for chocolate coloured animals (n = 34, 10.7 years, IQR 9.0–12.4, range 3.8–15.5) (P = 0.028). Of a random sample of 2074 (6.2%) Labrador retrievers under care in 2013 that had full disorder data extracted, 1277 (61.6%) had at least one disorder recorded. The total number of dogs who died at any date during the study was 176. The most prevalent disorders recorded were otitis externa (n = 215, prevalence 10.4%, 95% CI: 9.1–11.8), overweight/obesity (183, 8.8%, 95% CI: 7.6–10.1) and degenerative joint disease (115, 5.5%, 95% CI: 4.6–6.6). Overweight/obesity was not statistically significantly associated with neutering in females (8.3% of entire versus 12.5% of neutered, P = 0.065) but was associated with neutering in males (4.1% of entire versus 11.4% of neutered, P < 0.001). The prevalence of otitis externa in black dogs was 12.8%, in yellow dogs it was 17.0% but, in chocolate dogs, it rose to 23.4% (P < 0.001). Similarly, the prevalence of pyo-traumatic dermatitis in black dogs was 1.1%, in yellow dogs it was 1.6% but in chocolate dogs it rose to 4.0% (P = 0.011). Conclusions The current study assists prioritisation of health issues within Labrador retrievers. The most common disorders were overweight/obesity, otitis externa and degenerative joint disease. Males were significantly heavier females. These results can alert prospective owners to potential health issues and inform breed-specific wellness checks
- …