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1.
R Soc Open Sci ; 4(3): 160290, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28405350

RESUMEN

Cetacean energy stores are known to vary according to life history, reproductive status and time of year; however, the opportunity to quantify these relationships is rare. Using a unique set of historical whaling records from Western Australia (1952-1963), we investigated energy stores of large cetaceans with differing life histories, and quantified the relationship between total body lipid and length for humpback whales (Megaptera novaeangliae) (n = 905) and sperm whales (Physeter macrocephalus) (n = 1961). We found that total body lipid increased with body length in both humpback and sperm whales, consistent with size-related energy stores. Male humpback whales stored 2.49 kl (15.6 barrels) (31.9-74.9%) more lipid than male sperm whales of equivalent length, to fuel their annual migration. Relative lipid stores of sperm whales (males) were constant throughout the year, while those of humpback whales varied with reproductive class and sampling date. Pregnant female humpback whales had higher relative energy stores than non-pregnant females and males (26.2% and 37.4%, respectively), to fuel the energy demands of gestation and lactation. Those that reached the sampling site later (en route to their breeding grounds) carried higher lipid stores than those that arrived earlier, possibly reflecting individual variation in residency times in the Antarctic feeding grounds. Importantly, longer pregnant females had relatively larger energy stores than the shorter pregnant females, indicating that the smaller individuals may experience higher levels of energetic stress during the migration fast. The relationships we developed between body lipid and length can be used to inform bioenergetics and ecosystem models when such detailed information is not available.

2.
Front Neurol ; 7: 105, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27445969

RESUMEN

Intraoperative monitoring is performed to provide real-time assessment of the neural structures that can be at risk during spinal surgery. Somatosensory evoked potentials (SEPs) are the most commonly used modality for intraoperative monitoring. SEP stability can be affected by many factors during the surgery. This study is a prospective review of SEP recordings obtained during intraoperative monitoring of instrumented spinal surgeries that were performed for chronic underlying neurologic and neuromuscular conditions, such as scoliosis, myelopathy, and spinal stenosis. We analyzed multiple montages at the baseline, and then followed their development throughout the procedure. Our intention was to examine the stability of the SEP recordings throughout the surgical procedure on multiple montages of cortical SEP recordings, with the goal of identifying the appropriate combination of the least number of montages that gives the highest yield of monitorable surgeries. Our study shows that it is necessary to have multiple montages for SEP recordings, as it reduces the number of non-monitorable cases, improves IOM reliability, and therefore could reduce false positives warnings to the surgeons. Out of all the typical montages available for use, our study has shown that the recording montage Cz-C4/Cz-C3 (Cz-Cc) is the most reliable and stable throughout the procedure and should be the preferred montage followed throughout the surgery.

3.
Neurosurg Rev ; 37(3): 461-70; discussion 470-1, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24578098

RESUMEN

This study aims to evaluate the improvements of cardinal motor symptoms depending on the stimulation site relative to a standardized, reconstructed three-dimensional MRI-defined subthalamic nucleus (STN.) This retrospective, clinical study includes 22 patients with idiopathic Parkinson's disease, who consecutively underwent bilateral subthalamic nucleus stimulation. Intraoperative microelectrode recording and clinical testing were performed. The location of the best stimulation site, found intraoperatively, and the positions of the active electrode contacts 12 months after the operation were correlated to a standardized, reconstructed three-dimensional MRI-defined STN. Further, the impact of the stimulation site on rigidity, tremor and akinesia was analysed. Significant improvement of the contralateral akinesia was observed if the intraoperative stimulation site was located more lateral and superior in the MRI-STN. Furthermore, active electrode contacts located superior to or in the superior part of the MRI-STN had a significantly better effect on the tremor of the contralateral hand than in other locations inside the STN. For rigidity and akinesia, these correlations were statistically not significant. Although we found significantly better results for tremor suppression in superior and lateral aspects of the STN, for overall clinical improvement, several patients fared better with randomly distributed stimulation sites in medial, posterior or inferior parts of the MRI-defined STN. Locations of stimulation sites with the best improvements of motor symptoms were distributed randomly throughout the whole MRI-defined STN, indicating that MRI-based targeting alone is not sufficient, but intraoperative clinical testing is necessary to determine the optimal stimulation site for each individual patient.


Asunto(s)
Estimulación Encefálica Profunda , Locomoción , Imagen por Resonancia Magnética , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/cirugía , Anciano , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología , Estudios Retrospectivos , Núcleo Subtalámico/fisiopatología , Resultado del Tratamiento
4.
Aging Ment Health ; 17(5): 535-43, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23421691

RESUMEN

OBJECTIVES: Discrepancies in ratings of ability are used to assess awareness in people with cognitive impairments, and previously have been found to be associated with comorbid depression and carer distress. This study explored how the degree of discrepancy between self-ratings of ability made by older people with a cognitive impairment and informant ratings made by their partners relates to aspects of their relationship quality. It was hypothesised that discrepancies between self- and partner ratings would be associated with partner's expressed emotion (EE), and replicate previous findings for associations with depression and carer distress. METHOD: Forty-six people aged over 65 with mild cognitive impairment or early-stage dementia were recruited through NHS mental health services for older people. In a semi-structured interview, they and their partners gave separate ratings of cognitive abilities and instrumental activities of daily living (IADL). Partners also completed a 5-minute speech sample task to assess the type of EE. Depression in cognitively impaired participants and partner distress were also measured. RESULTS: High EE, depression and carer distress were associated with larger discrepancies in ratings of ability on the cognitive measure. EE was not associated with self-ratings or partner ratings of cognitive or IADL ability. CONCLUSION: The findings suggest that where disagreement about the abilities of an older person with cognitive impairments is greater, the affective environment around that person is more likely to be characterised by criticism and/or emotional over-involvement. The implications of this for assessment, diagnosis, and helping couples adjust to cognitive deterioration are discussed.


Asunto(s)
Demencia/psicología , Emoción Expresada , Esposos/psicología , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Evaluación Geriátrica , Humanos , Masculino , Investigación Cualitativa , Estrés Psicológico , Reino Unido
5.
Opt Express ; 19(27): 26768-82, 2011 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-22274260

RESUMEN

Fluorometers are widely used in ecosystem observing to monitor fluorescence signals from organic compounds, as well as to infer geophysical parameters such as chlorophyll or CDOM concentration, but measurements are susceptible to variation caused by biofouling, instrument design, sensor drift, operating environment, and calibration rigor. To collect high quality data, such sensors need frequent checking and regular calibration. In this study, a wide variety of both liquid and solid fluorescent materials were trialed to assess their suitability as reference standards for performance assessment of in situ fluorometers. Criteria used to evaluate the standards included the spectral excitation/emission responses of the materials relative to fluorescence sensors and to targeted ocean properties, the linearity of the fluorometer's optical response with increasing concentration, stability and consistency, availability and ease of use, as well as cost. Findings are summarized as a series of recommended reference standards for sensors deployed on stationary and mobile platforms, to suit a variety of in situ coastal to ocean sensor configurations. Repeated determinations of chlorophyll scale factor using the recommended liquid standard, Fluorescein, achieved an accuracy of 2.5%. Repeated measurements with the recommended solid standard, Plexiglas Satinice® plum 4H01 DC (polymethylmethacrylate), over an 18 day period varied from the mean value by 1.0% for chlorophyll sensors and 3.3% for CDOM sensors.


Asunto(s)
Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/normas , Espectrometría de Fluorescencia/instrumentación , Espectrometría de Fluorescencia/normas , Calibración , Análisis de Falla de Equipo/normas , Océanos y Mares , Estándares de Referencia , Estados Unidos
6.
J Clin Child Adolesc Psychol ; 39(6): 825-36, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21058129

RESUMEN

This study assessed the efficacy of a 5-week, intensive working memory training program for 52 children and adolescents (ages 7-17) who had Attention-Deficit/Hyperactivity Disorder (ADHD) and other comorbid diagnoses. This study provided a treatment replication since the waitlist control group also completed training and was included in the follow-up data analyses. Parents and teachers completed paper-and-pencil measures of working memory, executive functioning, and ADHD symptoms at baseline, posttreatment, and 4-month follow-up. Parent ratings indicated that participants improved on inattention, overall number of ADHD symptoms, initiation, planning/organization, and working memory. Teacher ratings approached significance at posttreatment and at 4-month follow-up on and Initiate scale. Working memory training appears promising as an intervention in improving executive functioning and ADHD symptoms.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Trastorno por Déficit de Atención con Hiperactividad/terapia , Terapia Cognitivo-Conductual , Función Ejecutiva , Memoria a Corto Plazo , Aprendizaje Verbal , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Niño , Comorbilidad , Docentes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Padres , Percepción Espacial , Enseñanza/métodos , Resultado del Tratamiento , Percepción Visual
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