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The Lower to Middle Jurassic Hazelton Group represents the final stage of magmatic arc activity in the intraoceanic Stikine terrane, which was followed by accretion within the Cordilleran terrane collage. The Hazelton Group is exposed in the following areas: (i) on the periphery of the Bowser Basin, where arc and back-arc strata are overlain by mainly sedimentary strata of the upper Hazelton Group and then by the clastic basin fill of the Bowser Lake Group; and (ii) within a 300 km long rift system, the Eskay rift, west of the Bowser basin, where a predominantly bimodal volcanic succession contains significant mineral deposits. Examination of representative stratigraphic sections throughout the regional extent of the upper Hazelton Group has suggested significant revisions and clarification of its stratigraphy and include the following: (i) informal division of the Hazelton Group into upper and lower parts and recognition of a diachronous unconformity or unconformities at the boundary between them; (ii) establishment of a type section for the sandstone-dominated Smithers Formation; (iii) establishment of separate Quock and revised Spatsizi formations in the north and extension of the Quock Formation to include all lithostratigraphically equivalent units of blocky, thinly bedded siliceous mudstone and tuff around the periphery of the Bowser basin; and (iv) introduction of the Iskut River Formation for rift-related and volcanic facies in the Eskay rift area. Two independent rifting events occurred during deposition of the Hazelton Group: a Late Sinemurian to Early Pliensbachian phase in the northwest-trending Hazelton trough and a more restricted Aalenian to Bajocian extensional event in the Eskay rift. Le Groupe de Hazelton (Jurassique inferieur a moyen) represente l'etape finale d'activite d'arc magmatique dans le terrane intra-oceanique Stikine, laquelle fut suivie par son accretion dans le collage de terranes de la Cordillere. Le Groupe de Hazelton affleure : (i) a la peripherie du bassin Bowser, ou des strates d'arc et d'arriere-arc sont recouvertes par des strates surtout sedimentaires du Groupe de Hazelton superieur et ensuite par le remplissage clastique de bassin du Groupe de Bowser Lake et (ii) dans un systeme de rifts d'une longueur de 300 km, le rift Eskay, a l'ouest du bassin Bowser, ou une succession volcanique principalement bimodale contient des gites mineraux significatifs. Un examen de sections stratigraphiques representatives a travers l'etendue regionale du Groupe de Hazelton superieur suggere d'importantes revisions et precisions de sa stratigraphie dont : (i) une division informelle du Groupe de Hazelton en parties inferieure et superieure et la reconnaissance d'une ou de plusieurs discordances diachroniques a la limite entre les parties; (ii) l'etablissement d'une section-type pour la Formation de Smithers, dominee par des gres; (iii) l'etablissement, au nord, d'une Formation de Quock distincte ainsi qu'une revision de la Formation de Spatsizi et l'extension de la Formation de Quock pour inclure toutes les unites a equivalence lithostratigraphique de mudstone et de tufs siliceux, a blocs et a lits minces, autour du bassin Bowser et (iv) l'introduction de la Formation d'Iskut River pour les facies volcaniques et ceux relies au rift dans la region du rift Eskay. Deux evenements independants de distension ont eu lieu durant la deposition du Groupe de Hazelton : une phase (Sinemurien tardif a Pliensbachien precoce) a tendance nord-ouest dans la fosse Hazelton et un evenement d'extension plus restreint (Aalenien a Bajocien) dans le rift Eskay. [Traduit par la Redaction], Introduction The Jurassic Period marks a key transition in the tectonics of the Canadian Cordillera. During this time, the western margin of North America was changing rapidly from a complex [...]

Highlights: [•] The identification of mental overload is a key factor to improve operators’ safety. [•] We used a simulated piloting task to elicit different levels of workload. [•] Workload was assessed by heart rate variability and near infrared spectroscopy. [•] Patterns of lower activation revealed mental overload at maximal task demand. [ABSTRACT FROM AUTHOR]

Obstructive sleep apnea (OSA) is characterised by repetitive cessation or reduction of airflow due to upper airway obstructions. These respiratory events lead to chronic sleep fragmentation and intermittent hypoxemia. Several studies have shown that OSA is associated with daytime sleepiness and cognitive dysfunctions, characterized by impairments of attention, episodic memory, working memory, and executive functions. This paper reviews the cognitive profile of adults with OSA and discusses the relative role of altered sleep and hypoxemia in the aetiology of these cognitive deficits. Markers of cognitive dysfunctions such as those measured with waking electroencephalography and neuroimaging are also presented. The effects of continuous positive airway pressure (CPAP) on cognitive functioning and the possibility of permanent brain damage associated with OSA are also discussed. Finally, this paper reviews the evidence suggesting that OSA is a risk factor for developing mild cognitive impairment and dementia in the aging population and stresses the importance of its early diagnosis and treatment. [ABSTRACT FROM AUTHOR]