RESUMEN
Runoff from the Greenland Ice Sheet (GrIS) is thought to enhance marine productivity by adding bioessential iron and silicic acid to coastal waters. However, experimental data suggest nitrate is the main summertime growth-limiting resource in regions affected by meltwater around Greenland. While meltwater contains low nitrate concentrations, subglacial discharge plumes from marine-terminating glaciers entrain large quantities of nitrate from deep seawater. Here, we characterize the nitrate fluxes that arise from entrainment of seawater within these plumes using a subglacial discharge plume model. The upwelled flux from 12 marine-terminating glaciers is estimated to be >1000% of the total nitrate flux from GrIS discharge. This plume upwelling effect is highly sensitive to the glacier grounding line depth. For a majority of Greenland's marine-terminating glaciers nitrate fluxes will diminish as they retreat. This decline occurs even if discharge volume increases, resulting in a negative impact on nitrate availability and thus summertime marine productivity.
Asunto(s)
Organismos Acuáticos/crecimiento & desarrollo , Dinámicas no Lineales , Estaciones del Año , Agua , Agua Dulce , Groenlandia , Cubierta de Hielo , Hierro/análisis , Nitratos/análisisRESUMEN
Family members are known to be highly influential in the development of sport expertise. To date, much of the research in this area has focused on parents, with less known about sibling influences on expertise. This investigation explored associations between sport expertise, sibling characteristics, and sibling participation in sport and physical activity. Athletes representing three skill levels provided details of sibling characteristics and participation in sport and physical activity via the Developmental History of Athletes Questionnaire. Elite athletes were more likely to be later-born children, while pre-elite and non-elite athletes were more likely to be first-born. Compared with siblings of non-elite athletes, siblings of elite athletes were more likely to have participated in regular physical activity and were more likely to have participated in sport at the pre-elite and elite levels. These results suggest siblings may play a key role in sport expertise development.
Asunto(s)
Rendimiento Atlético/clasificación , Orden de Nacimiento , Conducta Competitiva , Relaciones entre Hermanos , Hermanos , Adolescente , Adulto , Rendimiento Atlético/psicología , Conducta Competitiva/clasificación , Femenino , Humanos , Masculino , Actividad Motora , Aptitud Física , Hermanos/psicología , Encuestas y Cuestionarios , Adulto JovenRESUMEN
The authors studied six patients with refractory temporal lobe epilepsy and postictal psychosis using quantitative MRI and histopathology, and compared the results with 45 patients with temporal lobe epilepsy without postictal psychosis. Total hippocampal volumes were not different between the two groups. However, patients with postictal psychosis had a relatively preserved anterior hippocampus, and temporal lobe dysplasia was more frequent (p = 0.006, chi-square test). These findings may be associated with the clinical symptoms.
Asunto(s)
Corteza Cerebral/patología , Epilepsia del Lóbulo Temporal/patología , Hipocampo/patología , Trastornos Psicóticos/patología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , MasculinoRESUMEN
This study examined whether stroke lesions involving left hemisphere prefrontal or basal ganglia structures are associated with poststroke depression. A consecutive series of first-ever stroke patients with single small lesions on CT scan were examined for the presence and severity of poststroke depressive disorder. Lesions involving left prefrontal or basal ganglia structures were compared with other left hemisphere lesions and all right hemisphere lesions. Forty-one patients were examined. Patients with lesions involving left hemisphere prefrontal or basal ganglia structures had a higher frequency of depressive disorder (9/12; 75%) than other left hemisphere lesions (1/12; 8%) or those with right hemisphere lesions (5/17; 29%), P = 0.002. These findings suggest that damage to neural pathways within left hemisphere prefrontal or basal ganglia structures is associated with depressed mood following stroke.
Asunto(s)
Encéfalo/patología , Trastornos Cerebrovasculares/complicaciones , Trastorno Depresivo/etiología , Anciano , Ganglios Basales/patología , Trastornos Cerebrovasculares/patología , Femenino , Lóbulo Frontal/patología , Humanos , MasculinoRESUMEN
OBJECTIVE: To describe a case of neuroleptic malignant syndrome associated with risperidone. CLINICAL PICTURE: An elderly patient with bipolar affective disorder presented with neuroleptic malignant syndrome and relapse of hypomania after commencing risperidone. TREATMENT: Risperidone was ceased and the patient monitored closely. OUTCOME: The symptoms of neuroleptic malignant syndrome were resolved. CONCLUSION: To our knowledge this is the first such case reported, and suggests that risperidone, like other neuroleptics, is associated with neuroleptic malignant syndrome.
Asunto(s)
Antipsicóticos/efectos adversos , Trastorno Bipolar/tratamiento farmacológico , Síndrome Neuroléptico Maligno/diagnóstico , Risperidona/efectos adversos , Anciano , Antipsicóticos/administración & dosificación , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/psicología , Quimioterapia Combinada , Humanos , Masculino , Síndrome Neuroléptico Maligno/psicología , Examen Neurológico/efectos de los fármacos , Risperidona/administración & dosificaciónRESUMEN
The objective of this study was to describe the clinical characteristics of minor depression after stroke and to compare this disorder with poststroke major depression and the nondepressed state. Ninety-four stroke inpatients were examined 8 weeks after stroke and reexamined 15 months later. Twenty-one (22%) of the 94 patients suffered from minor depression, 14 (15%) suffered from major depression, and 59 (63%) were not depressed. Minor depressed patients were twice as symptomatic as nondepressed patients but were only half as symptomatic as major depressed patients. Minor depressed patients were more likely than nondepressed patients to have a previous history of stroke and were more physically disabled. They were less likely than major depressed patients to have a family history of affective disorder. Depression symptom severity was associated with greater physical disability among minor but not major depressed patients. Fewer minor than major depressed patients were depressed at 15 months. These findings suggest that poststroke major and minor depression may be different depressive syndromes. Some cases of minor depression may be construed as an adjustment reaction to stroke disability.