Publications by authors named "Canavan A"

Adaptive behaviors emerge in novel environments through functional changes in neural circuits. While relationships between circuit function and behavior have been well studied, how evolution shapes those circuits and leads to behavioral adpation is poorly understood. The Mexican cavefish, , provides a unique genetically amendable model system, equipped with above ground eyed surface fish and multiple evolutionarily divergent populations of blind cavefish that have evolved in complete darkness.

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The continuous introduction of micropollutants into the environment through livestock farming, agricultural practices, and wastewater treatment is a major concern. Among these pollutants are synthetic sulfonamide antibiotics such as sulfamethoxazole, which are not always fully degraded and pose a risk of fostering antimicrobial resistance. It is challenging to assess the degradation of sulfonamides with conventional concentration measurements.

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A matrix in highly complex samples can cause adverse effects on the trace analysis of targeted organic compounds. A suitable separation of the target analyte(s) and matrix before the instrumental analysis is often a vital step for which chromatographic cleanup methods remain one of the most frequently used strategies, particularly high-performance liquid chromatography (HPLC). The lack of a simple real-time detection technique that can quantify the entirety of the matrix during this step, especially with gradient solvents, renders optimization of the cleanup challenging.

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Purpose: International guidelines suggest the use of lapro-endoscopic technique for primary unilateral inguinal hernia (IHR) because of lower postoperative pain and reduction in chronic pain. It is unclear if the primary benefit is due to the minimally invasive approach, the posterior mesh position or both. Further research evaluating posterior mesh placement using open preperitoneal techniques is recommended.

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We present the data from a crowdsourced project seeking to replicate findings in independent laboratories before (rather than after) they are published. In this Pre-Publication Independent Replication (PPIR) initiative, 25 research groups attempted to replicate 10 moral judgment effects from a single laboratory's research pipeline of unpublished findings. The 10 effects were investigated using online/lab surveys containing psychological manipulations (vignettes) followed by questionnaires.

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The most useful individual signs for identifying dehydration in children are prolonged capillary refill time, abnormal skin turgor, and abnormal respiratory pattern. However, clinical dehydration scales based on a combination of physical examination findings are better predictors than individual signs. Oral rehydration therapy is the preferred treatment of mild to moderate dehydration caused by diarrhea in children.

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Objective: To validate a tool for assessment of accumulated damage in patients with Primary SS (PSS).

Methods: Of the total 114 patients fulfilling American-European Consensus Group (AECG) criteria for PSS 104 were included in the study and assessed by rheumatologists at T (time) = 0 months and T = 12 months. On each occasion, damage and activity data, and autoantibody status were collected.

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Objective: This article describes the development of the Sjögren's Systemic Clinical Activity Index (SCAI) for the measurement of systemic disease activity in patients with primary Sjögren's syndrome (PSS).

Methods: A pilot tool was developed based on expert consensus and previous published data. One hundred and four patients with PSS were evaluated in a cross-sectional analysis, of whom 65 were reviewed at 3-monthly intervals, using this index, over a 12-month period.

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We aimed at investigating whether on-line and delayed visual pattern processing activated different areas in human prefrontal and parietal cortex. For this purpose we measured the regional cerebral blood flow (rCBF) during simultaneous and successive visual matrix processing in 10 right-handed subjects. Delayed matching to sample activated predominantly left hemispheric ventrolateral prefrontal cortex, Broca's area and parts of the parietal cortex.

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We studied changes in regional cerebral blood flow (rCBF) in 10 healthy right-handed subjects during a visuospatial imagery task. The subject's task consisted of drawing imagined lines connecting encircled numbers in ascending order and estimating the number of lines crossing. Compared with a control task in which there were no crossed lines, there were significant rCBF increases in the cingulate gyrus, the adjacent superior frontal gyrus and in the left inferior parietal cortex.

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Three groups of five parasite-naive calves were used. The treatments were: (a) Group 1 calves were weighed on Day 0 and injected with doramectin at 200 microg/kg. From Day 1 to 19 they were dosed orally with 2000 infective larvae of Dictyocaulus viviparus.

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Studies of motor imagery and motor learning have thus far been concerned only with its effects on healthy subjects. Therefore, in order to investigate the possible involvement of the basal ganglia, the effectiveness of motor imagery in the acquisition of motor constants in a graphomotor trajectorial learning task was examined in 11 non-demented mildly affected Huntington's disease (HD) patients and 12 non-demented Parkinson's disease (PD) patients. The patients received, after baseline, 10 min of motor imagery training, followed by a motor practice phase.

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Insulin resistance, without frank diabetes, is associated with sudden cardiac death. We postulated that a potential mechanism for this association is autonomic dysfunction. Male Sprague-Dawley rats were randomized into one of two groups: (a) insulin resistant (IR; n = 15), or (b) control (n = 11).

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Background: The government encourages general practitioners (GPs) to become involved in caring for drug users. However, in some areas of the country, including Bedford, secondary care support is inadequate. GPs in these areas have to decide how to cope with such patients entirely within general practice.

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There are contrasting reports upon the level of effectiveness of motor imagery in learning new motor skills, but there is general consensus that motor imagery can lead to improvements in performance, especially in combination with physical practice. In the present study we examined the effectiveness of motor imagery in the acquisition of movement invariants in two grapho-motor trajectorial learning tasks with differing visuospatial components: 'Ideogram drawing' and 'connecting circles'. Two subject groups were studied: An imagery group, which underwent 10 min of motor imagery training and a control group, which practised a control visuomotor task over the same period of time.

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The aim of this study was to identify the cerebral areas activated during kinematic processing of movement trajectories. We measured regional cerebral blood flow (rCBF) during learning, performance and imagery of right-hand writing in eight right-handed volunteers. Compared with viewing the writing space, increases in rCBF were observed in the left motor, premotor and frontomesial cortex, and in the right anterior cerebellum in all movement conditions, and the increases were related to mean tangential writing velocity.

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This study was motivated by the fact that unilateral neglect, an impediment to progress in patient rehabilitation, is often reported to occur in a wider area of space than that usually assessed in clinical settings. Neglect within "grasping space" (Halligan & Marshall, 1991; Kolb & Whishaw, 1990) was assessed via two search tasks: one in which search was guided by visual information and the other in which search was guided by tactile information. The performance of 10 left brain-damaged patients (LBD) and 20 right brain-damaged patients, 10 of whom showed left visual neglect (RBD+) while 10 did not (RBD-), was compared with that of age-matched controls.

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In this paper the performance of patients with unilateral hemispheric lesions (n = 10 with right brain damage; n = 10 with left brain damage) on a free-field sound localization task was contrasted with that of healthy controls (n = 10). Sound stimuli were presented binaurally in the horizontal plane from eight loudspeakers set at azimuths between -105 degrees and +105 degrees. Whereas performance of both patient groups was generally less accurate than controls, no evidence suggested that this was specific to the contralateral hemisphere.

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Transcranial magnetic stimulation (TMS) of human motor cortex typically evoked motor responses. TMS has failed to elicit eye movements in humans, whereas prolongations of saccadic latency have been reported with TMS. In previous studied we demonstrated that saccades can be abolished or saccadic trajectories can be changed through TMS in the 100 msec before saccade onset.

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The performances of 12 patients with Parkinson's disease (PD), 16 with Huntington's disease (HD), and young and old healthy controls were assessed on a number of tests of verbal and nonverbal declarative memory, on a test of nonmotor conditional associative learning (words and colors), and on a number of reaction time (RT) tasks. The RT tasks consisted of cued simple and choice reactions. The relationship between the precue and the imperative stimulus in the S1-S2 paradigm was nonarbitrary in the first series and arbitrary in the second series.

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The structures of the human brain engaged during learning of unilateral trajectorial hand movements were mapped by measurements of regional cerebral blood flow. Trajectorial movement velocity accelerated moderately after short-term training p < 0.025 and increased further after long-term training p < 0.

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Eight patients with lesions restricted to the cerebellum were compared with a total of 25 age-matched controls on a reaction time (RT) task allowing the recording of simple and choice RTs as well as RTs to abstract visual patterns signifying the particular movement to be performed. In all conditions the actual movements required (either a left or a right button press) remained the same, but the cognitive requirements of the task varied. In the abstract patterns condition, the significance of the various patterns with regard to the required movement had to be learned by the subjects.

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The functional significance of plasma HLA class I antigens is unclear. They are thought to have an immunomodulatory role and be tolerogenic in transplant settings including the materno-fetal semi-allograft. There is, however, no available data on the concentrations of soluble HLA class I antigens in fetuses or newborns.

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The hypothesis was tested that proximal and distal reaction times (RTs) might be differentially affected in Parkinson's disease (PD). Twelve patients with PD were compared with 12 age-matched healthy controls on tests of finger-, hand-, leg-, and torso-RTs. Patients were significantly slower in initiating all movements and were slower in executing all movements except for the leg (stepping) task.

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