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This study investigated the nonlinear changes in the vertical motion of 411 GNSS reference stations situated in mainland China and assessed the influence of the environmental load on their vertical displacement. The researchers evaluated the effect of environmental load by calculating the change in annual cycle amplitude before and after its removal, focusing on its impact across regions with distinct foundation types. The results demonstrate that removing the environmental load led to a considerable reduction of approximately 50.25% in the annual cycle amplitude of vertical motion for GNSS reference stations in mainland China. This reduction in amplitude improved the positioning accuracy of the stations, with the highest WRMS reduction being 2.72 mm and an average reduction of 1.03 mm. The most significant impact was observed in the southwestern, northern, and northwestern regions, where the amplitude experienced a notable decrease. Conversely, the southeastern region exhibited a corresponding increase in amplitude. This article innovatively explored the effects of environmental loads on diverse foundation types. When categorizing GNSS reference stations based on their foundation type, namely, bedrock, 18 m soil layer, and 4–8 m soil layer stations, this study found that removing the environmental load resulted in reductions in annual cycle amplitudes of 49.37%, 59.61%, and 46.48%, respectively. These findings indicate that 18 m soil layer stations were more susceptible to environmental load-induced vertical motion. In conclusion, the impact of the environmental load was crucial when analyzing the vertical motion of GNSS reference stations in mainland China, as it was essential for establishing a high-precision coordinate reference framework and studying the tectonic structure of the region. [ABSTRACT FROM AUTHOR]

Abstract: Geobacillus thermodenitrificans NG80-2 is a crude oil-degrading thermophilic bacterium isolated from an oil reservoir in China. In this study, the gene clusters and pathways for the degradation of benzoate (via benzoyl-CoA), phenylacetate (via phenylacetyl-CoA), 4-hydroxyphenylacetate (via 3,4-dihydroxyphenylacetate) and anthranilate (via 3-hydroxyanthranilate) were confirmed using combined in silico analysis and proteomics approaches. It was observed that synthesis of the enzymes catalyzing initial activation, ring oxidation and ring cleavage reactions were generally induced specifically by their respective substrates, while many of the enzymes catalyzing downstream reactions exhibited broader substrate specificities. Novel genes encoding benzoyl-CoA epoxidase and 3,4-dihydroxyphenylacetate 2,3-dioxygenase, and a paaX homologue that serves as a positive regulator of benzoate degradation were proposed. Downregulation of the glycolysis pathway, along with upregulation of the gluconeogenesis pathway and the glyoxylate bypass (phenylacetate) were detected in association with the utilization of the aromatics. This novel proteomics approach confirmed the presence of multiple metabolic pathways for aromatic compounds in NG80-2, which is highly advantageous to the survival of this thermophilic bacterium under reservoir conditions. [Copyright &y& Elsevier]

Abstract: The Geodetic datum is significance to national economic construction. By analyzing the situation that Chinese original infrastructure was old and damaged, and the technical system was imperfect, this paper proposes a high-precision, geocentric, dynamic and unified modern geodetic datum design including horizontal datum, height datum and gravity datum. Among them, 410 national reference stations using global navigation satellite system have been designed nationwide, reaching an average station spacing of about 70km in the eastern region and about 150km in the western region. At the same time, 4500 GNSS geodetic control points were designed as the encryption and supplement of the reference stations, with an average point spacing of about 40km; The census and redesign of the original national first-class level network reached a total length of 125,600 kilometers, including 148 rings and 431 leveling routes. On the basis of the absolute gravity point in the country, 50 new reference stations are selected as the absolute gravity reference points, and the average point spacing is about 300km. In 2012, China launched the major infrastructure construction project "National Modern Geodetic Datum Infrastructure Construction", which was completed in May 2017, and 2017-2018 is the initial application of engineering results. The geometric attributes and physical attributes of the surveying and mapping results are unified, realizing the dynamic update of the national coordinate framework and international integration, and has the ability to the national real-time decimeter accuracy, providing national navigational positioning service capability with real-time decimeter accuracy.Key words: Geodetic datum; GNSS reference stations; GNSS geodetic control network; Height control network [ABSTRACT FROM AUTHOR]

Abstract: In recent years, the BDS wide-area differential positioning is a cutting-edge issues for application of satellite navigation system, which can provide decimeter even centimeter level precision real-time positioning. This paper introduces the construction and positioning testing of national BDS wide-area differential system using 210 national continuous operating reference stations that are able to receive data from GPS and BDS satellites. These observation data are processed in real time to obtain products including GPS&BDS satellites real-time precision orbits, clocks and ionospheric delay et.al. The accuracy of these products is assessed automatically, the results show that the 3D RMS of difference with IGS final orbit is better than 10cm for GPS real-time precise orbit products, and better than 30cm for BDS IGSO/MEO real-time orbit products and better than 2m for BDS GEO. The bias of real-time clock difference products is better than 1.3ns for GPS and better than 2ns for BDS. The precise is better than 7 TECU for real-time ionospheric delay products. Those products are broadcasted through the wireless communication network to users, and they that can obtain high-precision positioning by real-time PPP. We have conducted extensive real-time PPP testing in various regions of China using handheld terminal. After 15 minutes of convergence, the PPP precision in BDS-only mode is better than 15 cm in horizontal and better than 20 cm in vertical components. In BDS&GPS mode, the precision is better than 3 cm in horizontal and better than 4 cm in vertical components, respectively.Key words: BDS wide-area differential, satellite orbit, satellite clock, ionospheric delay, positioning precision [ABSTRACT FROM AUTHOR]

• The volatile compounds in fresh leaves from 22 major oolong tea cultivars predominantly cultivated in Fujian of China were analyzed using SPME and GC–MS. • The PCA and HCA with leaf volatile compositions notably highlighted the significant distinctions of FS, DHP, SJG, and JMD from the remaining tea cultivars. • The analysis of nonadditive volatiles in tea hybrids revealed a noteworthy positive MPH in JGY and HMG. • JGY exhibited a marked positive MPH in aldehydes, aromatic hydrocarbons, and epoxides, whereas HMG displayed a pronounced positive MPH in aldehydes, epoxides, and esters. Tea is highly esteemed by consumers due to its distinct aroma and the abundance of nutrients that contribute to human well-being. While volatile compounds in fresh tea leaves serve as the essential foundation for tea aroma, the understanding of cultivar-specific aroma constituents and their genetic regulation remains a research gap. In this study, we extracted and profiled the volatile compounds in fresh leaves from 22 major oolong tea cultivars using gas chromatography-mass spectrometry. A total of 140 volatile compounds were identified, of which 61 were consistently found in all tea cultivars. The volatile profiles of the 22 tea cultivars exhibited considerable dissimilarity, with several distinct cultivar-specific volatiles identified. Subsequent analysis of nonadditive volatiles in tea hybrids revealed a noteworthy positive mid-parent heterosis (MPH) in 'Mingke 1' (also known as 'Jinguanyin') and 'Huangmeigui'. Comprehensive heterosis across various volatile compounds was also documented. Our study elucidated the composition of volatile compounds in the fresh leaves from the major oolong tea cultivars and provided an extensive exploration of volatile heterosis in tea plants. These cultivar-specific volatile variations will offer essential insights for enhancing the genetic aspects of tea aroma flavor and deepen our understanding of the molecular mechanisms underlying volatile compound formation in fresh tea leaves. [ABSTRACT FROM AUTHOR]

Importance: A higher incidence of pancreatic cancer has been reported in the Chinese population compared with the White population, but genetic differences are unknown to date. Large-sample germline testing for both familial and sporadic pancreatic cancers has been conducted predominantly in White populations, whereas similar studies in Chinese populations are limited., Objective: To assess the prevalence of germline sequence variations in patients with pancreatic diseases in China., Design, Setting, and Participants: This genetic association study was a case series that included genetic data from patients with pancreatic ductal adenocarcinoma (PDAC) or non-PDAC pancreatic diseases seen at The First Affiliated Hospital of Nanjing Medical University in Nanjing, China, between January 2006 and December 2017 (Nanjing cohort). Comparator group data were obtained for a US cohort from Johns Hopkins Hospital (JHH), a population from East Asia from the Exome Aggregation Consortium (ExAC) database, and the larger population from China from the ChinaMAP database. Data were updated and analyzed in July 2021., Main Outcomes and Measures: Next-generation sequencing technology was used to examine the prevalence of deleterious variations in 59 genes of the included Chinese patients with DNA extracted from peripheral blood samples. The Fisher exact test was used to assess differences among the frequencies of germline variations in the study patients vs the comparator groups., Results: A total of 1009 patients with PDAC (627 [62.1%] male; mean [SD] age, 62.8 [10.2] years) and 885 with non-PDAC diseases (477 [53.9%] male; mean [SD] age, 52.0 [15.9] years) from the Nanjing cohort were included for genetic analysis; all were Han Chinese individuals. Pathogenic variations were detected in 63 patients with PDAC (6.2%; 95% CI, 4.7%-7.7%). Variations in BRCA2 (odds ratio [OR], 3.2; 95% CI, 1.4-7.7; P = .008) and PALB2 (OR, 5.2; 95% CI, 1.6-17.0; P = .007) were significantly associated with pancreatic risk in the Nanjing cohort. Pathogenic variants of genes associated with homologous recombination DNA damage repair, including ATM, BRCA1/2, PALB2, BRIP1, FANCA, FANCC, RAD51D, and XRCC2, were found in 34 patients with PDAC (3.4%). No Ashkenazi Jewish-specific BRCA2 variation (p.Ser1982fs) was detected. The odds ratio of a SPINK1 variation in patients with PDAC was 3.2 (95% CI, 1.8-5.7; P < .001) in the Nanjing cohort compared with the ExAC cohort. Variations in the pancreatic secretory enzyme genes CPA1 and CPB1 were not detected in the Nanjing cohort., Conclusions and Relevance: In this genetic association study, sporadic pancreatic cancer was associated with pathogenic germline variations in a cohort from China. These findings provide insights into the genetic background of pancreatic cancer in the Han Chinese population with PDAC.