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3.
Nature ; 571(7765): 393-397, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31316195

RESUMEN

Existing estimates of sea surface temperatures (SSTs) indicate that, during the early twentieth century, the North Atlantic and northeast Pacific oceans warmed by twice the global average, whereas the northwest Pacific Ocean cooled by an amount equal to the global average1-4. Such a heterogeneous pattern suggests first-order contributions from regional variations in forcing or in ocean-atmosphere heat fluxes5,6. These older SST estimates are, however, derived from measurements of water temperatures in ship-board buckets, and must be corrected for substantial biases7-9. Here we show that correcting for offsets among groups of bucket measurements leads to SST variations that correlate better with nearby land temperatures and are more homogeneous in their pattern of warming. Offsets are identified by systematically comparing nearby SST observations among different groups10. Correcting for offsets in German measurements decreases warming rates in the North Atlantic, whereas correcting for Japanese measurement offsets leads to increased and more uniform warming in the North Pacific. Japanese measurement offsets in the 1930s primarily result from records having been truncated to whole degrees Celsius when the records were digitized in the 1960s. These findings underscore the fact that historical SST records reflect both physical and social dimensions in data collection, and suggest that further opportunities exist for improving the accuracy of historical SST records9,11.


Asunto(s)
Conjuntos de Datos como Asunto/normas , Calentamiento Global/estadística & datos numéricos , Agua de Mar/análisis , Temperatura , Aire/análisis , Océano Atlántico , Conjuntos de Datos como Asunto/historia , Mapeo Geográfico , Alemania , Calentamiento Global/historia , Historia del Siglo XX , Japón , Océano Pacífico , Reproducibilidad de los Resultados
5.
Mov Disord ; 32(6): 904-912, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28218416

RESUMEN

BACKGROUND: Early theories for cervical dystonia, as promoted by Hassler, emphasized the role of the midbrain interstitial nucleus of Cajal. Focus then shifted to the basal ganglia, and it was further supported with the success of deep brain stimulation. Contemporary theories suggested the role of the cerebellum, but even more recent hypotheses renewed interest in the midbrain. Although the pretectum was visited on several occasions, we still do not know about the physiology of midbrain neurons in cervical dystonia. METHODS: We analyzed the unique database of pretectal neurons collected in the 1970s and 1980s during historic stereotactic surgeries aimed to treat cervical dystonia. This database is valuable because such recordings could otherwise never be obtained from humans. RESULTS: We found the following 3 types of eye or neck movement sensitivity: eye-only neurons responded to pure vertical eye movements, neck-only neurons were sensitive to pure neck movements, and the combined eye-neck neurons responded to eye and neck movements. There were the 2 neuronal subtypes: burst-tonic and tonic. The eye-neck or eye-only neurons sustained their activity during eccentric gaze holding. In contrast, the response of neck-only and eye-neck neurons exponentially decayed during neck movements. CONCLUSIONS: Modern quantitative analysis of a historic database of midbrain single units from patients with cervical dystonia might support novel hypotheses for normal and abnormal head movements. This data, collected almost 4 decades ago, must be carefully viewed, especially because it was acquired using a less sophisticated technology available at that time and the aim was not to address specific hypothesis, but to make an accurate lesion providing optimal relief from dystonia. © 2017 International Parkinson and Movement Disorder Society.


Asunto(s)
Conjuntos de Datos como Asunto , Movimientos Oculares/fisiología , Movimientos de la Cabeza/fisiología , Cuello/fisiopatología , Neuronas/fisiología , Área Pretectal/fisiopatología , Tegmento Mesencefálico/fisiopatología , Tortícolis/fisiopatología , Conjuntos de Datos como Asunto/historia , Electromiografía , Electrooculografía , Historia del Siglo XX , Humanos , Neuronas/citología , Técnicas de Placa-Clamp , Área Pretectal/citología , Tegmento Mesencefálico/citología , Tortícolis/historia
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