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Accurate assessments of population sizes and trends are fundamental for effective species conservation, particularly for social and long-lived species in which low reproductive rates, aging demographic structure and Allee effects could interact to drive rapid population declines. In the parrots (Order Psittaciformes) these life history characteristics have combined with habitat loss and capture for the pet trade to lead to widespread endangerment, with over 40% of species classified under some level of threat. Here we report the results of a population survey of one such species, the Yellow-naped Amazon, Amazona auropalliata, that is classified as ‘Endangered’ on the IUCN Red List. We conducted a comprehensive survey in June and July of 2016 of 44 night roosts of the populations in contiguous Pacific lowlands of northern Costa Rica and southern Nicaragua and compared numbers in Costa Rica to those found in a similar survey conducted in June 2005. In 2016 we counted 990 birds across 25 sites surveyed in Costa Rica and 692 birds across 19 sites surveyed in Nicaragua for a total population estimate of only 1,682 birds. Comparisons of 13 sites surveyed in both 2005 and 2016 in Costa Rica showed a strong and statistically significant decline in population numbers over the 11-year period. Assessment of group sizes approaching or leaving roosts indicated that less than 25% of groups consisted of three or more birds; there was a significantly higher proportion of these putative family groups observed in Nicaragua than Costa Rica. Taken together, these results are cause for substantial concern for the health of this species in a region that has previously been considered its stronghold, and suggest that stronger conservation action should be undertaken to protect remaining populations from capture for the pet trade and loss of key habitat.
Nepal has a high prevalence of chronic suppurative otitis media and hearing impairment. An improved understanding of patients' knowledge, attitudes, beliefs and practices is therefore important for effective healthcare planning and intervention.
Questionnaires designed to explore their current knowledge, attitudes, beliefs and practices were completed by 153 participants: 71 were affected by a known ear disease and 82 were unaffected.
In the unaffected group, 31.7 per cent considered breast milk to be a risk factor for ear infection. Home remedies (e.g. leaf paste, oils, and urine and/or bodily fluids) had been used by 42.3 per cent of the affected group. Most participants (71.9 per cent) believed that society discriminates against those with hearing impairment.
Knowledge deficits and false beliefs were found in both groups, along with a significant use of home remedies and a perception of discrimination against people with hearing impairment. These findings are relevant for healthcare providers and may aid the development of policy, interventions and public education initiatives.
Autobiographical memory (ABM), personal semantic memory (PSM), and autonoetic consciousness are affected in individuals with mild cognitive impairment (MCI) but their relationship with Alzheimer's disease (AD) biomarkers are unclear.
Forty-five participants (healthy controls (HC) = 31, MCI = 14) completed the Episodic ABM Interview and a battery of memory tests. Thirty-one (HC = 22, MCI = 9) underwent β-amyloid positron emission tomography (PET) and magnetic resonance (MR) imaging. Fourteen participants (HC = 9, MCI = 5) underwent one imaging modality.
Unlike PSM, ABM differentiated between diagnostic categories but did not relate to AD biomarkers. Personal semantic memory was related to neocortical β-amyloid burden after adjusting for age and apolipoprotein E (APOE) ɛ4. Autonoetic consciousness was not associated with AD biomarkers, and was not impaired in MCI.
Autobiographical memory was impaired in MCI participants but was not related to neocortical amyloid burden, suggesting that personal memory systems are impacted by differing disease mechanisms, rather than being uniformly underpinned by β-amyloid. Episodic and semantic ABM impairment represent an important AD prodrome.
Using transient imaging data from the 2nd and 3rd years of the SDSS supernova survey, we apply various machine learning techniques to the problem of classifying transients (e.g. SNe) from artefacts, one of the first steps in any transient detection pipeline, and one that is often still carried out by human scanners. Using features mostly obtained from PCA, we show that we can match human levels of classification success, and find that a K-nearest neighbours algorithm and SkyNet perform best, while the Naive Bayes, SVM and minimum error classifier have performances varying from slightly to significantly worse.
Clinical neurophysiology encompasses a variety of diagnostic tests including EEG, nerve conduction studies, electromyography, evoked potentials and polysomnography. This chapter describes the tests that are most widely used for monitoring during neuroanaesthesia and neurocritical care, specifically, EEG, somatosensory evoked potentials (SSEPs), brainstem auditory evoked potentials, motor evoked potentials (MEPs) and electromyography (EMG). The main indications for EEG are in the diagnosis and management of epilepsy, sleep studies and neuromonitoring. Evoked potentials are the electrical response from the nervous system to an external stimulus. There are two types of EPs: sensory and motor. SSEPs monitor the integrity of sensory pathways, including peripheral nerves, and MEPs the motor pathways. Electromyography is a technique used to evaluate the electrical activity in muscle fibres. Two types of EMG monitoring commonly used include: recording spontaneous electrical activity and recording responses generated by stimulation of motor nerves.
The cerebral circulation is protected from systemic blood pressure surges by a complex branching system and two resistance elements: the first of these lies in the large cerebral arteries, and the second in vessels of diameter <100 μm. Endothelial cells in cerebral capillaries contain few pinocytic vesicles and are sealed with tight junctions, without any anatomical gap. Several endogenous substances including catecholamines and vascular growth enhancing factor can dynamically modulate blood-brain barrier (BBB) permeability. Classical cerebral autoregulation assessment does not consider the latency of autoregulatory mechanisms, focusing instead on the maintenance of cerebral blood flow (CBF) at different steady state levels of cerebral perfusion pressure (CPP). Methods of measuring CBF may be regional or global, and may be applicable either to humans or primarily to experimental animals. Severe head injury is accompanied by both direct and indirect effects on CBF and metabolism, which show both temporal and spatial variations.