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Background The correct reference range for maternal thyroid function during pregnancy is essential for making an accurate diagnosis of thyroid disease and delivering proper interventions in pregnant women. But there is still no universal standard for this in women with a twin pregnancy. Objective To determine a rational reference range for maternal thyroid function during twin pregnancies. Methods Healthy pregnant women who underwent antenatal examination in Obstetric Clinic, Beijing Friendship Hospital, Capital Medical University from January 2009 to September 2019 were retrospectively selected, including 352 with a twin pregnancy (twin group) , and 988 with a singleton pregnancy (singleton group) . Clinical and laboratory data were collected. The lower and upper limits for determining normal maternal thyroid function during twin pregnancies were the 2.5 (P2.5) and 97.5 (P97.5) percentiles of TSH and FT4. Clinical hyperthyroidism was defined as TSHP97.5 (total FT4) . Clinical hypothyroidism was defined as TSH>P97.5 (total TSH) and FT4P97.5 and P2.5≤FT4≤P97.5. Low T4 syndrome was diagnosed by P2.5 (total TSH) ≤TSH≤P97.5 (total TSH) and FT4

The Hailar–Tamtsag Basin (HTB), an important component of the late Mesozoic extensional basin system in Northeast (NE) China, is characterized by episodic rifting, dramatic magmatism, and thick terrestrial sediments, which provides crucial opportunities to understand late Mesozoic tectonomagmatic events in NE China. However, the previously established late Mesozoic chronostratigraphic framework in the basin remains problematic due to limited isotopic chronological constraints. Here, we present 28 new zircon U–Pb ages for the volcanic rocks from the HTB, which allow us to establish a refined chronostratigraphic framework for the late Mesozoic terrestrial strata. Newly calibrated results indicate that the depositional ages of the Tamulangou and Tongbomiao formations are constrained to ca. 157–148 and ca. 142–137 Ma, respectively; the depositional ages of the Lower Nantun and Upper Nantun members are constrained to ca. 131–120 and ca. 117–111 Ma, respectively. Combining these results with previous studies on sedimentation, structural deformation, and magmatism, the Late Jurassic–Early Cretaceous tectonostratigraphic evolution of the HTB is reconstructed, and three major phases of intracontinental deformation are identified. The HTB experienced extensional deformation in the Late Jurassic due to the break‐off of the subducted oceanic slab of the Mongol–Okhotsk Ocean and subsequent gravitational collapse of orogenically thickened crust following the closure of the ocean basin. Then, in the latest Jurassic–earliest Cretaceous, the evolution of the HTB was dominated by compressional deformation related to flat‐slab subduction of the Paleo‐Pacific Plate. During the Early Cretaceous, an extensional regime resumed in the HTB in response to rollback of the subducting Paleo‐Pacific Plate. [ABSTRACT FROM AUTHOR]

The lithospheric mantle beneath the Xing'an Massif (XM), northeast China, was formed at the Paleoproterozoic or even earlier, but its thermal state and structure remain poorly understood. To address this issue, we calculate pressure–temperature (P–T) arrays for mantle xenoliths entrained by Cenozoic basalts from the XM, using major‐element‐based and rare earth element (REE)‐based two‐pyroxene thermometry as well as single clinopyroxene barometry. Samples (include spinel or garnet lherzolites and harzburgites, dunite and pyroxenite) come from the Keluo, Nuomin, and Aershan regions, which are located on either side of the North–South Gravity Lineament (NSGL). To the west of the NSGL, in the Nuomin and Aershan regions, mantle xenoliths yield consistent REE‐based and major‐element‐based temperatures, suggesting that these samples were derived from stable thermal conditions. Garnet peridotites from these regions yield pressures of 2.37–3.01 GPa and temperatures of 1066–1303°C, revealing a high geothermal gradient (corresponding to a surface heat flow of 70–80 mW/m2) and a crustal thicknesses of ~37 km. The lithosphere–asthenosphere boundary determined from the intersection of this geotherm with the mantle adiabat occurs at a depth of ~100 km, which is much shallower than the lithospheric thickness calculated by geophysical analyses (140–160 km). This discrepancy may have resulted from locally upwelling hot asthenosphere. Low‐temperature (800–900°C) peridotites from the Nuomin and Aershan are chemically fertile with low olivine Mg# values and high modal clinopyroxene contents. By contrast, high‐temperature (1050–1350°C) peridotites consist mainly of refractory harzburgites or clinopyroxene‐poor lherzolites. These facts reveal that the lithospheric mantle beneath the Nuomin and Aershan regions is characterized by juvenile mantle dominating shallow levels and ancient mantle occurring at greater depths. To the east of the NSGL, some Keluo mantle xenoliths yield higher REE‐based temperatures (839–863°C) than major‐element‐based temperatures (<800°C), indicating cooling by thermal relaxation. This cooling process produced a low geothermal gradient (~45 mW/m2) in the lithosphere beneath the Keluo region. The mantle xenoliths comprise both fertile lherzolites and refractory harzburgites without correlation between mineral compositions and temperatures, suggesting that the lithospheric mantle beneath the Keluo region is characterized by juvenile mantle mixed with ancient mantle at all depths. The results show contrasting thermal state and structure of the lithospheric mantle on either side of the NSGL within the XM, which are attributed to a previous cooling process in the Keluo region and local upwelling of hot asthenosphere beneath the Aershan and Nuomin regions. [ABSTRACT FROM AUTHOR]

In order to reveal the phenotypic variation of Lilium brownii in natural populations native to Qinba moun-tainous area, and to discuss the relationship between phenotypic variation of natural populations, a systematic investi-gation was carried out among 17 natural populations in this area, containing 21 quantitative traits and 8 qualitative traits of both the flowers and the leaves.The results were as follows:with a strong adaptability, L .brownii had a wide distribution range of this area, most of them lived in mountains at an altitude height varying from 705 m to 1 913 m;Rich variation took place in the phenotypic traits.The length of the top leaves had a notably positive correlation with latitude, the width of the stigmas and the length of the top leaves had a notably positive correlation with altitude, the bottom leaf spacing had a notably positive correlation with the annual precipitation, while the length of pedicel and the length of the top leaves had a significantly negative correlation with the mean annual temperature;L .brownii n-ative to Qinba mountainous area could be divided into 2 groups:Group Qinling and Group Bashan, according to the re-sults of UPGMA cluster analysis.These findings may offer basic data for further studies on genetic breeding and con-servation biology of L .brownii . [ABSTRACT FROM AUTHOR]

Background: Understanding the impact of early sensory deficits on brain development is essential for understanding developmental processes and developing potential interventions. While previous studies have looked into the impact of prenatal experiences on language development, there is a lack of research on how these experiences affect early language and brain function development in individuals with sensorineural hearing loss (SNHL)., Aim: To investigate SNHL effects on early brain development and connectivity in 4-month-olds vs healthy newborns and controls., Methods: The research involved analyzing the functional brain networks of 65 infants, categorized into three groups: 28 healthy newborns, 22 4-month-old participants with SNHL, and 15 age-matched healthy participants. The resting-state functional connectivity was measured and compared between the groups using functional near-infrared spectroscopy and graph theory to assess the brain network properties., Results: Significant differences were found in resting-state functional connectivity between participants with SNHL and age-matched controls, indicating a developmental lag in brain connectivity for those with SNHL. Surprisingly, SNHL participants showed better connectivity development compared to healthy newborns, with connectivity strengths of 0.13 ± 0.04 for SNHL, 0.16 ± 0.08 for controls, and 0.098 ± 0.04 for newborns. Graph theory analysis revealed enhanced global brain network properties for the SNHL group, suggesting higher communication efficiency at 4 months. No significant differences were noted in network properties between 4-month-old SNHL participants and neonates. A unique pattern of central hubs was observed in the SNHL group, with 2 hubs in the left hemisphere compared to 6 in controls., Conclusion: 4-month-old infants with SNHL have a distinct brain network pattern with efficient long-distance information transmission but less effective local communication compared to age-matched controls., Competing Interests: Conflict-of-interest statement: The authors declare that they have no conflict of interest., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)