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BackgroundIndividuals may experience significant alterations in sleep hygiene during the major public health emergencies， consequently impacting their sleep quality.ObjectiveTo explore the relationship between sleep quality and sleep hygiene among adult residents during the major public health emergencies， so as to provide references for improving the sleep quality of residents during such a period.MethodsA sample of 1 364 adult residents were enrolled as the research subjects from February 20 to 29， 2020. All participants were asked to complete self-administered questionnaire to obtain basic-demographic information and sleep hygiene. Pittsburgh Sleep Quality Index （PSQI） was applied to assess sleep quality. Residents were classified into poor sleepers with PSQI score ≥8 and good sleepers defined as PSQI score

Magmatic periodicity is recognized in continental arcs worldwide, but the mechanism responsible for punctuated arc magmatism is controversial. Continental arcs in the Trans‐Himalayan orogenic system display episodic magmatism and the most voluminous flare‐up in this system was in early Eocene during the transition from subduction to collision. The close association of the flare‐up with collision is intriguing. Our study employs zircon Lu‐Hf and bulk rock Sr‐Nd isotopes, along with mineral geochemistry, to track the melt sources of the Nymo intrusive complex and the role of mantle magma during the early Eocene flare‐up of the Gangdese arc, Tibet. The Nymo intrusive complex is composed of gabbronorite, diorite, quartz diorite, and granodiorite which define an arc‐related calc‐alkaline suite. Zircon U‐Pb ages reveal that the complex was emplaced between ~50–47 Ma. Zircon Hf isotopes yield εHf(t) values of 8.2–13.1, while whole‐rock Sr and Nd isotopes yield εNd(t) values of 2.7–6.5 indicative of magmatism dominated by melting of a juvenile mantle source with only minor crustal assimilation (~15%–25%) as indicated by assimilation and fractional crystallization modeling. Together with published data, the early Eocene magmatic flare‐up was likely triggered by slab breakoff of subducted oceanic lithosphere at depths shallower than the overriding plate. The early Eocene magmatic flare‐up may have contributed to crustal thickening of the Gangdese arc. This study provides important insights into the magmatic flare‐up and its significant role in the generation of large batholiths during the transition from subduction to collision. [ABSTRACT FROM AUTHOR]

The formation of the Jurassic Xiongcun porphyry copper deposit, within the Gangdese magmatic belt of southern Tibet, took place coincident with subduction of the Neotethyan oceanic lithosphere. Although the Yeba Formation (coeval and co-magmatic intrusions and volcanic rocks) in the eastern Gangdese magmatic belt formed at the same time as the Xiongcun deposit, the Yeba Formation is devoid of subduction-related porphyry Cu deposits. Here, we report detrital zircon U-Pb ages for sedimentary rocks of the Yeba and Bima Formations along with a summary of all published whole-rock geochemical data and zircon epsilon Hf isotopes for the volcanic rocks in the Yeba Formation. We use these data to re-evaluate the petrogenesis, magmatic source, and tectonic setting of the volcanic rocks. Detrital zircon ages from the sedimentary rocks reveal that the volcanic rocks of the Yeba and Bima Formations are the main source for their sedimentary interlayers. In addition, the Yeba sedimentary layers contain inherited zircons sourced from older country rocks whereas the Bima Formation is devoid of ancient zircons. Geochemically, the Yeba volcanic rocks resemble a bimodal volcanic suite. Geochemical data reveal that the Yeba volcanic rocks formed in a continental arc setting, while the mafic ones were derived from the partial melting of the mantle wedge above the subducting slab rather than from the melting of the descending oceanic slab. In addition, the mafic ensemble formed in a back-arc setting, indicative of subduction-related extension in the Lhasa terrane. In contrast, the felsic ensemble may originate from the melting of basaltic lower crust. Thus, the magma source and tectonic setting for the Yeba Formation are distinct from typical subduction-related Cu-hosted porphyry and volcanic rocks in a compressional setting. [ABSTRACT FROM AUTHOR]

The Central Asian Orogenic Belt is an accretionary orogen with many distinct terranes including the Chinese Central Tianshan, whose Precambrian tectonic affinity is not yet clearly known. We present Precambrian age spectra of inherited/xenocrystic zircons from magmatic rocks in the Chinese Central Tianshan, collected from published papers. The age patterns are dominated by zircons with ages ranging from 3261 to 541 Ma. These spectra provide robust clues regarding the Precambrian affinity of the Chinese Central Tianshan. The age spectra record two major tectonothermal events, represented by salient age peaks of c. 950 and 900 Ma within the ‘Grenville Orogeny’ period, and age peaks at c. 750 and 630 Ma, synchronous with magmatic events corresponding to Rodinia break-up. These results are consistent with the hypothesis that the Chinese Central Tianshan was part of the Tarim craton during Precambrian time as well as documenting its incorporation into, and separation from the Rodinia landmass. [ABSTRACT FROM AUTHOR]

We report petrologic, geochemical, and zircon U−Pb and Hf isotope data from an early Palaeozoic mafic-intermediate suite of rocks in Baluntai, heartland of the Central Tianshan. Analysed major elements of the intermediate rocks show a close affinity to metaluminous I-type granitoids, resembling arc plutons. The mafic rocks display depletions of Nb, Ta, and Ti typical of volcanic arc basalts (VAB). All of the samples fall within the subduction-related field in tectonic discrimination diagrams. Zircons from a granodiorite and a hornblende diorite yield indistinguishable crystallization ages of 475.1 ± 1.7 million years and 473.7 ± 1.6 Ma, indicating an early Palaeozoic magmatic event. Zircons in the mafic rocks yield younger crystallization ages of 427 ± 1 Ma and 426.5 ± 1.4 Ma. Combined with previous published results, our data suggest that the southward subduction of the Palaeo-Tianshan oceanic crust beneath the northern margin of the Tarim block probably began no later than Early Ordovician time and did not end prior to the middle Silurian. Zircons from the granodiorite and hornblende diorite show ϵHf(t) values of −11.19 to −5.98 and −12.85 to −6.01, respectively, suggesting the reworking of ancient crust. Correspondingly, these zircons yield twoTDM2age ranges: 2140–1812 Ma and 2241–1812 Ma, probably representing a significant episode of juvenile addition during the assembly of Columbia. In contrast, zircons from the mafic rocks yield ϵHf(t) values of 3.12–8.91 and 3.19–8.76, corresponding to theTDM1ages ranging from 911 to 685 Ma and from 905 to 688 Ma, respectively, suggesting crustal growth in the Central Tianshan microcontinent associated with the initial break-up of Rodinia. [ABSTRACT FROM AUTHOR]