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Cherts and silicified dolostones of the ca. 1600 Ma Dahongyu Formation (uppermost Changcheng Group) from North China contain well-preserved microfossils. Cyanobacteria filaments and coccoids dominate the studied Dahongyu microbiota in the Jixian section. These microfossils show the characteristics of endobenthic, epibenthic, and allochthonous microfossils, which illustrated well a vertical distributional view of an intertidal microbiota. Large numbers and size of allochthonous microfossils are the distinguishing characteristics of this new microbiota. A few of these possess ornaments or odd morphology, which suggest their potential eukaryotic nature. Through regional comparisons, it is revealed that there was significant regional disparity within the Yanshan Basin of microbiotas during deposition of the Dahongyu Formation. The newly studied Dahongyu microbiota is similar to the microbiota from the underlying Changcheng Group, with only slight differences. The absence of typical eukaryotes and the emergence of unique microfossils (especially small fusiform microfossils) make the Dahongyu Formation and the subsequent strata of the Jixian Group distinct from contemporaneous eukaryote-bearing strata.In the Dahongyu assemblage, 19 species were recognized, six species were identified informally and seven species were identified in open nomenclature. One new taxon of microfossil was described: Xiaohongyuia sinica Shi and Feng new genus new species. [ABSTRACT FROM AUTHOR]

The long-term overexploitation of groundwater leads to serious land subsidence and threatens the safety of Beijing-Tianjin-Hebei (BTH). In this paper, an interferometric point target analysis (IPTA) with small baseline subset InSAR (SBAS-InSAR) technique was used to derive the land subsidence in a typical BTH area from 2012 to 2018 with 126 Radarsat-2 and 184 Sentinel-1 images. The analysis reveals that the average subsidence rate reached 118 mm/year from 2012 to 2018. Eleven subsidence features were identified: Shangzhuang, Beijing Airport, Jinzhan and Heizhuanghu in Beijing, Guangyang and Shengfang in Langfang, Wangqingtuo in Tianjin, Dongguang in Cangzhou, Jingxian and Zaoqiang in Hengshui and Julu in Xingtai. Comparing the different types of land use in subsidence feature areas, the results show that when the land-use type is relatively more complex and superimposed with residential, industrial and agricultural land, the land subsidence is relatively more significant. Moreover, the land subsidence development patterns are different in the BTH areas because of the different methods adopted for their water resource development and utilization, with an imbalance in their economic development levels. Finally, we found that the subsidence changes are consistent with groundwater level changes and there is a lag period between land subsidence and groundwater level changes of approximately two months in Beijing Airport, Jinzhan, Jingxian and Zaoqiang, of three months in Shangzhuang, Heizhuanghu, Guangyang, Wangqingtuo and Dongguang and of four months in Shengfang. [ABSTRACT FROM AUTHOR]

Objective: To summarize the clinical and dermatoscopic features of temporal triangular alopecia in infants and explore the clinical significance of dermatoscopy in the diagnosis of triangular alopecia temporalis in infants. Methods: A retrospective analysis was performed on 20 children with temporal triangular alopecia diagnosed in the dermatology clinic of Tianjin Children's Hospital from January 2015 to December 2021. Dermatoscopy was performed on all children, and images were collected. Results: The clinical features of 20 children were 15 males and five females, all of which were born immediately after birth; There were eight cases (40%) in the left temporal region, 10 cases (50%) in the right temporal region, one case (5%) in the head region, and one case (5%) in the occipital region; 19 cases were single (95%), one case was multiple (5%); There were 21 skin lesions, 15 triangular lesions (71.4%), four quasi‐circular lesions (19%), and two lance‐shaped lesions (9.5%). Trichoscopic features: The hair follicle opening in all skin lesions is normal, and the hair follicle opening can be seen with fluffy hair (vellus hair). The vellus hair is evenly distributed, and the length is diverse (both short and long vellus hair exist in the same hair loss area). There are 14 cases of white vellus hair (70%), five cases of white spots (25%), one case of honeycomb pigment pattern (5%), and one case of vascular dilation pattern (5%). Conclusion: Temporal triangular alopecia in infants has typical clinical and dermatoscopic characteristics, and the dermatoscopy can provide clinical basis for its diagnosis and differential diagnosis. [ABSTRACT FROM AUTHOR]

Regional land subsidence is an integrated systematic issue related to multidisciplinary andbeing of global focus, and has been being a serious threat to the urban infrastructure,high-speed railway and the utilization of underground space, and restricting the sustainabledevelopment of society. The study of the regional subsidence evolution in Beijing Plain is ofgreat significance: it is necessary to reveal the regional land subsidence evolution law underthe background of Integration of Beijing-Tianjin-Hebei and the South-to-NorthWater Diversion. Furthermore, it can help to realize the scientific regulation ofregional subsidence and ensure the sustainable development of regional economy andsociety, which has a special significance and application prospect. Therefore theMT-InSAR method is used to obtain the regional ground subsidence time seriesinformation of the study area in three periods: Jun. 2003 ∼ Aug. 2010, Oct. 2010 ∼ Nov.2015, and May. 2015 ∼ Jun. 2018. Then equations are established based on thetime-overlapping information to complete the fusion of multi-platform time series, theinconsistence between different reference points is solved, simultaneously. Theresults show that, the maximum subsidence values in Beijing Plain are 690.6 mm,649.2 mm and 411.7 mm during the three periods, with maximum deformationrates of 100.6 mm/a, 130.0 mm/a and 142.3 mm/a, respectively. For the spatialdistribution and the evolution of the land subsidence field, the weighted spatialkernel density analysis, profile analysis, trend-surface analysis and profile-gradientanalysis are used to analyze the spatial-temporal evolution characteristics of theland subsidence field. In this case, land subsidence in Beijing Plain are thoroughlyanalyzed overall distribution characteristics and evolution process. Nine subsidencecenters are identified and the subsidence centers are connecting to form a mainsubsidence area in the northern part of Beijing Plain. The spatial clustering degree ofthe subsidence in the Beijing Plain indicates an overall heterogeneity in spatial.Moreover, the northern subsidence areas spread along the Nankou-Sunhe fault, and iscut into several subsidence centers by active faults, indicating that the regionalgeological structure has obvious control effect on the spatial distribution of landsubsidence areas. The evolution of the subsidence field: the northern subsidence areasspread along the northwest-southeast direction, and then expands to both the east andwest sides. Then through the distribution of subsidence areas and groundwaterfunnel, the InSAR based time series and the monitoring well based groundwater levelchanges, the correlations in spatial and responses between land subsidence field andgroundwater flow field are analyzed. The results show that the subsidence centerin the northern Beijing Plain is consistent with the groundwater drop funnel inspatial, with a similar downward trend over the whole observation time. Through theanalysis of well based results located in different areas, the long term groundwaterexploitation in the northern subsidence area has led to the continuous decline ofthe water level, resulting in the inelastic and permanent compaction; while for themonitoring wells located outside the subsidence area, the subsidence time seriesshow obvious elastic deformation characteristics as the groundwater level changes. [ABSTRACT FROM AUTHOR]