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Understory small trees and shrubs play a crucial role in the biogeochemical cycles in forest ecosystems. However, their biomass in northeastern China is still uncertain and has been heavily disregarded due to the limited number of available allometric equations. For this study, 782 plants from 33 species obtained by the destructive method were used to develop species-specific and generalized aboveground allometric biomass equations based on collar diameter (D) and height (H) using weighted nonlinear seemingly unrelated regression. Each biomass component was shown to be well predicted by D alone, with R2 adj. values mostly greater than 0.80. The majority of species performed better in the models for wood and aboveground biomass when H was included as D2H. Furthermore, generalized equations for the two components showed a comparatively large coefficient of variation but comparable Bias to species-specific equations, especially for small trees. It is recommended to estimate biomass using generalized equations for mixed species only when species-specific equations are unavailable at a given site. However, in the event when precision is not the primary concern, generalized equations are also suggested. The developed equations will help to improve the accuracy of biomass assessment of understory woody plants in northeastern China forest ecosystems. [ABSTRACT FROM AUTHOR]

Background: The first local outbreak of Delta Variant B.1.617.2 COVID-19 of China occurred in Guangzhou city, south China, in May 2021. This study analyzed the transmission chains and local cluster characteristics of this outbreak, intended to provide information support for the development and adjustment of local prevention and control strategies. Methods: The transmission chains and local cluster characteristics of 161 local cases in the outbreak were described and analyzed. Incubation period, serial interval and generation time were calculated using the exact time of exposure and symptom onset date of the cases. The daily number of reported cases and the estimated generation time were used to estimate the effective reproduction number (Rt). Results: We identified 7 superspreading events who had more than 5 next generation cases and their infected cases infected 70.81%(114/161) of all the cases transmission. Dining and family exposure were the main transmission routes in the outbreak, with 29.19% exposed through dining and 32.30% exposed through family places. Through further analysis of the outbreak, the estimated mean incubation period was 4.22 (95%CI: 3.66–4.94) days, the estimated mean generation time was 2.60 (95%CI: 1.96–3.11) days, and the estimated Rt was 3.29 (95%CI: 2.25–5.07). Conclusions: Classification and dynamically adjusted prevention and control measures had been carried out according to analysis of transmission chains and epidemical risk levels, including promoting nucleic acid screening at different regions and different risk levels, dividing closed-off area, controlled area according to the risk of infection, raising the requirements of leaving Guangzhou. By the above control measures, Guangzhou effectively control the outbreak within 28 days without implementing a large-scale lockdown policy. [ABSTRACT FROM AUTHOR]

Based on the recent oil and gas discoveries and geological understandings on the ultra-deep strata of sedimentary basins, the formation and occurrence of hydrocarbons in the ultra-deep strata were investigated with respect to the processes of basin formation, hydrocarbon generation, reservoir formation and hydrocarbon accumulation, and key issues in ultra-deep oil and gas exploration were discussed. The ultra-deep strata in China underwent two extensional-convergent cycles in the Meso-Neoproterozoic Era and the Early Paleozoic Era respectively, with the tectonic-sedimentary differentiation producing the spatially adjacent source-reservoir assemblages. There are diverse large-scale carbonate reservoirs such as mound-beach, dolomite, karst fracture-vug, fractured karst and faulted zone, as well as over-pressured clastic rock and fractured bedrock reservoirs. Hydrocarbons were accumulated in multiple stages, accompanied by adjusting and finalizing in the late stage. The distribution of hydrocarbons is controlled by high-energy beach zone, regional unconformity, paleo-high and large-scale fault zone. The ultra-deep strata endow oil and gas resources as 33% of the remaining total resources, suggesting an important successive domain for hydrocarbon development in China. The large-scale pool-forming geologic units and giant hydrocarbon enrichment zones in ultra-deep strata are key and promising prospects for delivering successive discoveries. The geological conditions and enrichment zone prediction of ultra-deep oil and gas are key issues of petroleum geology. [ABSTRACT FROM AUTHOR]

Mammalia cysteamine (2-aminoethanethiol) dioxygenase (ADO) controls the stability of the regulator of G protein signaling 4 (RGS4) through the Cys branch of the Arg/N-degron pathway, thereby affecting the response of the body to hypoxia. However, the oxygen-sensing function of ADO remains unknown in teleost fish. Mandarin fish (Siniperca chuatsi) is one of the most important freshwater economic fishes in China. As the scale of the rearing density continues to increase, hypoxia has become an important factor threatening the growth of mandarin fish. Herein, the molecular characterization, the oxygen-sensing enzyme function, and the role in virus infection of ADO from mandarin fish (scADO) were explored. Bioinformation analysis results showed that scADO had all the molecular foundations for achieving thiol dioxygenase function: three histidine residues coordinated with Fe(II), PCO/ADO domain, and a "jelly roll" β-barrel structure. The expression pattern analysis showed that scAdo was highly expressed in the immune-related tissues, liver, and kidneys and responded to hypoxia on the expression level. Protein degradation experiment results revealed that scADO could lead to the degradation of RGS4 protein through the Cys branch of the Arg/N-degron pathway. Furthermore, the expression levels of scADO responded to fish virus infection. scADO could significantly promote the replication of Siniperca chuatsi rhabdovirus, and this was associated with its thiol dioxygenase activity. These findings not only demonstrate scADO as an oxygen-sensing protein in teleost fish, but are also of considerable importance for clarifying the contribution of the mechanism of hypoxia to the outbreaks of fish viruses. [ABSTRACT FROM AUTHOR]

Adverse childhood experiences (ACEs) affect children's development, and their harm to health is pervasive throughout the life course. To identify ACEs and their risk factors in Chinese household with or without parental mental illness. A controlled study was conducted among 181 young adults with parental mental illness (positive group) and 201 demographically matched individuals without parental mental illness (negative group). Univariate and multivariate analyses were performed to study the correlation between ACEs and their risk factors. The positive group suffered emotional abuse, domestic violence, bullying, and cumulative ACEs more frequently than the negative group. In the positive group, living in rural areas and having a low household economic status during childhood were identified as risk factors for cumulative ACEs, whereas a higher education level of the mother was a protective factor for cumulative ACEs in univariate analyses. Low household economic status remained an independent risk factor for cumulative ACEs in the positive group in multivariate analyses. Children living with parental mental illness are more vulnerable to ACEs, and our findings highlight the importance of socioeconomic factors in increasing the risk of ACEs. To alleviate the deleterious impact of parental mental illness on offspring, multidimensional supports are needed. [ABSTRACT FROM AUTHOR]

Aim: To translate and test the psychometric properties of a Chinese version scale to measure the Fear of Activity in patients with Coronary Artery Disease. Design: A cross‐sectional design. Methods: The translation of the scale to measure Fear of Activity in Patients with Coronary Artery Disease included three steps, forward‐back translation, expert discussion and pilot survey. The internal consistency and test–retest reliability were used to assess the reliability of the Chinese version scale of the Fear of Activity. Content, construct, criterion, and known‐group validity of the scale were also evaluated. Data Sources: A total of 275 patients with Coronary Artery Disease were recruited from a university‐affiliated hospital in Guangzhou, southern China. Results: The overall content validity index of the Chinese version scale of the Fear of Activity in Patients with Coronary Artery Disease was 0.90. Principal component analyses extracted four factors with a cumulative variance contribution of 57.5%. There is a strong correlation (r = 0.83) between this scale and Tampa Scale for Kinesiophobia Heart. The total scores of the Chinese version scale of the Fear of Activity in female patients were higher than those in male patients with Coronary Artery Disease, indicating that the scale was able to distinguish the differences between low and high score groups. The Internal consistency and test–retest reliability coefficients of the scale were 0.74 and 0.82, respectively. Conclusion: The Chinese version scale of the Fear of Activity in Patients with Coronary Artery Disease, which consists of 21 items with four dimensions, is a reliable and valid instrument to evaluate the fear of activity in patients with Coronary Artery Disease. Implications for the Profession and/or Patient Care: The Chinese version scale of the Fear of Activity in Patients with Coronary Artery Disease can be used to assess the levels of fear of activity in patients with Coronary Artery Disease and explores the factors that influence fear of activity in the population. Impact: This study translates and confirms the psychometric properties of the Chinese version scale of the Fear of Activity in Patients with Coronary Artery Disease in China. It is useful in both research and clinical fields to explore the fear of activity and its associated factors in patients with Coronary Artery Disease. Reporting Method: The study design followed the guideline of Strengthening the Reporting of Observational Studies in Epidemiology statement. Patient or Public Contribution: Patients in a university‐affiliated hospital participated in this study and contributed to data collection. [ABSTRACT FROM AUTHOR]

With the targets of petroleum exploration transferred to the deep and ancient strata, abundant oil and gas resources have been found in Lower Paleozoic and older strata in central and western China. Due to complex evolutionary processes including multiple episodes of hydrocarbon accumulation and ubiquitously accompanied by secondary alterations, significant uncertainties remain concerning the generation time and accumulation processes of these revealed petroleum sources. In this paper, relative pure Re and Os elements existing in the asphaltene fractions of Lower Cambrian solid bitumen collected from the Guangyuan area, western Sichuan Basin, SW China and Middle–Lower Ordovician heavy oils in the Aiding area of the Tahe oilfield in the Tarim Basin, NW China were successfully obtained by sample pretreatments, and Re–Os isotopic analysis was subsequently carried out for the dating of these. The Re–Os isotopic composition indicates a generation time of Guangyuan bitumen to between 572 Ma and 559 Ma, corresponding to the late Sinian period of the Neoproterozoic era. By the means of Re–Os isochron aging, initial 187Os/188Os ratios, and carbon isotopic compositions, the Lower Cambrian bitumen is supposed to originate from source rocks of the Doushantuo Formation in the Sinian strata and subsequently migrated into the reservoirs of the Dengying Formation. This previously reserved petroleum was transformed into its present bitumen state by the destruction of reservoirs caused by tectonic uplift. The Re–Os dating results of Middle–Lower Ordovician heavy oil of Tarim Basin suggest that it was formed between 450 Ma to 436 Ma, corresponding to the Late Ordovician–Early Silurian system, and the generated petroleum likely migrate into the Middle–Lower Ordovician karst reservoirs to form early oil reservoirs. With tectonic uplift, these oil reservoirs were degraded and reformed to the heavy-oil reservoirs of today. [ABSTRACT FROM AUTHOR]

Near-surface energy budget closure has been a trending topic in land surface processes research, especially on the underlying surfaces of heterogeneous wetlands. In this investigation, the horizontal thermal advection caused by thermal inhomogeneity over the alpine wetland is calculated based on the eddy covariance data observed at the Flower Lake observation field and WRF modelling data over the Zoige alpine wetland, China. The contribution of horizontal thermal advection to the near-surface energy closure is analysed. The results show that the mean horizontal heat advection of the Zoige wetland is 20.2 W·m−2, and the maximum value reached 55.0 W·m−2 in the summer of 2017. After introducing thermal advection into the near-surface energy balance equation, the near-surface energy closure ratio increased from 72.3% to 81.0%. [ABSTRACT FROM AUTHOR]

A series of marginal-sea basins and fault-depression basins were formed in eastern China under the background of subduction of the West Pacific plate. Different types of helium-rich natural gas reservoirs (He>1000 ppm, 1 ppm=1 µmol mol−1) have been found in these basins: helium-rich CO2 gas reservoirs, helium-rich N2 gas reservoirs, and helium-rich hydrocarbon gas reservoirs. Based on the analysis of gas geochemical data, the source and accumulation mechanism of helium in these helium-rich natural gas reservoirs were discussed. Helium-rich natural gas has relatively high 3He/4He ratios (0.88–4.91 Ra, average 2.82 Ra). The 3He/4He ratio characteristics of mantle xenoliths and mantle-derived CO2 gas reservoirs indicate that the helium in these helium-rich natural gas reservoirs is mainly mantle-derived (>70%). The original mantle volatile is mainly CO2 with a low helium concentration (He<200 ppm), and the enrichment of mantle-derived helium in the gas reservoir is mainly related to the dissolution and mineralization of CO2. During this process, the CO2/3He ratio decreases from 2×109 to approximately 2×106. As CO2 dissolves and mineralizes, the concentration of conservative gases (He and N2) increases in the remaining CO2 gas proportionally to the loss of CO2. Large amounts of carbonate minerals, such as dawsonite, which are relatively enriched in 13C, are found in CO2 reservoirs in eastern China. The relative enrichment of 12C in residual CO2 gas is important evidence of the dissolution and mineralization of CO2. The relative abundance of mantle-derived helium and N2 gas increases thousands of times during the dissolution and mineralization of CO2, which is the main accumulation mechanism of mantle-derived helium-rich CO2 gas reservoirs and helium-rich N2 gas reservoirs. Helium-rich gas from the mantle is mixed with alkane gas generated by organic matter in the sedimentary basin to form helium-rich hydrocarbon gas reservoirs. [ABSTRACT FROM AUTHOR]

Since the 1920s, fossil erinaceids have been found in several dozen Quaternary localities in China. Previously, most of them were provisionally classified in eurytopic Erinaceus. This limits understanding of the authentic diversity and evolution of Erinaceinae in China and the reconstruction of their paleohabitats. We reviewed all accessible erinaceid fossils found in the Quaternary deposits in China. An erinaceid fragmentary mandible collected from the early Pleistocene deposits in Tianzhen county, Shanxi Province in North China was classified as Mesechinus cf. hughi, which is the oldest definite report of fossil Mesechinus in China. We considered that Erinaceus koloshanensis Young and Liu (1950) from Geleshan, Chongqing Municipality, should be transferred to Mesechinus as M. koloshanensis, and E. olgae Young (1934) from Zhoukoudian, Beijing, should be considered as a synonym of M. dauuricus. Our re-examination supplies a fossil calibration for the previous molecular phylogeny of the Erinaceinae. The earliest Mesechinus appeared in the early Pleistocene with the representative Mesechinus cf. hughi, M. dauuricus occurred in the middle Pleistocene and Erinaceus amurensis is also dated to the middle Pleistocene. Compared with Erinaceus, Mesechinus occupies a narrower niche and could be a potential indicative genus for a woodland or forest environment. [ABSTRACT FROM AUTHOR]

Purpose: The microbial community in the pit mud correlated closely with the quality of the final product of Chinese strong-flavored Baijiu (CSFB). However, environmental conditions and brewing processes can vary by region and distilleries. This may lead to differences in microbial composition and function in pit mud. Therefore, revealing the features of the pit mud microbial community structure and functions of different distilleries will provide key information for understanding the diversity and difference of microbes in the brewing of CSFB, which will be beneficial for the improvement of the quality of pit mud and CSFB in the future. Methods and results: Illumina MiSeq sequencing of 16S rRNA gene amplicons was used to analyze the similarities and differences in microbial community structure and function in pit muds of different distilleries located in Shihezi (Xinjiang), Xiangyang (Hubei), and Yibin (Sichuan). At the genus level, Clostridium, Lactobacillus, Aminobacterium, Petrimonas, Syntrophomonas, Methanoculleus, Syntrophaceticus, Sedimentibacter, Caloramator, Ruminococcus, Bacillus, Methanosarcina, and Garciella were the dominated genera of pit muds. There were great differences in the composition of microorganisms in pit muds used by different distilleries. The significantly enriched prokaryotic microbiotas of pit muds collected in the distilleries of Xiangyang were mainly affiliated with Bacillus, Lactobacillus, and Croceifilum, and the relative abundance of methanogens, such as Methanomicrobia and Methanobacteria, were only significantly enriched in the pit mud collected from the distilleries of Yibin (P < 0.05). Functional analysis indicated that the difference of microbial composition in pit mud will further lead to significant differences in various metabolic functions. Conclusion: The compositions and functions of dominant microorganisms in pit mud used for the production of CSFB by different enterprises across regions in China were greatly different, and there was a close relationship between the compositions and functions of microorganisms in pit mud. Therefore, it may be an effective method to improve CSFB fermentation processes by directionally regulating the microbial community functions of pit mud using specific strains. [ABSTRACT FROM AUTHOR]

Background: Natural ecosystems provide necessary services for human beings, including ecosystem service values (ESVs) and socioeconomic service values (SSVs). The value orientations of ESVs and SSVs are mainly related to people's interaction with nature. This study reclassified greenspace from a perspective of exposed and non-exposed greenspace based on the level of interaction by people and greenspace. We applied an expert questionnaire to survey the SSVs value orientations of forestland, grassland, wetland, and water bodies, and quantitatively compared the value orientations between the ESVs and SSVs of greenspace in China. Result: (1) The values of exposed greenspace were relatively far higher than non-exposed greenspace, as it had both ESVs and SSVs. (2) The forestland and grassland had relatively high ESVs and SSVs, and are the priority for both the exposed and non-exposed greenspace. (3) Wetland had relatively high ESVs but low SSVs, which was unpopular for exposed greenspace. (4) The ESVs and SSVs of water body were relatively balanced. Conclusion: Greenspace had both ESVs and SSVs when they are exposed to human. Our study provided an innovative perspective to explore the value orientations of greenspace, which provides an actionable scientific basis for greenspace planning, design and construction in human habitat.. [ABSTRACT FROM AUTHOR]

Graptolite-rich shale is the main layer of shale gas resources in the southern marine sedimentary basin. Recently, shale gas resources were discovered in the Ordovician marine graptolite-rich strata in the Ordos Basin. The graptolite shale in the study area is different from the marine graptolite shale in the Yangtze plate in southern China, and further exploration is needed. This paper presents core samples of the graptolite-rich shale of the Pingliang Formation in the southwest Ordos Basin as research objects. The graptolite genus and graptolite shale characteristics were studied using core observation, electron microscopy, scanning electron microscopy, and geochemical analysis. We determined the role of the sedimentary environment and thermal maturation of graptolite shale in hydrocarbon formation and explored the possibility of hydrocarbon generation. Many graptolite epidermises provide buried organic matter. The quiet sea and low-energy marine environment create favorable conditions for preserving organic matter. The tectonic process resulted in the evolution stage in the oil generation window. Different types of pores formed the spaces of hydrocarbons. Therefore, the shale of the Pingliang Formation has shale oil exploration potential, which complements the shale gas in the northwestern margin of the basin, and provides new venues for shale oil and gas exploration in northern China. [ABSTRACT FROM AUTHOR]

This study aims to examine the association between short-term exposure to ambient PM1, PM1-2.5, and PM2.5 and forced vital capacity (FVC). Population data were obtained from a school-based cross-sectional survey in Shandong in 2014. Distributed lag non-linear models were used to examine the association between exposure to PM1, PM1–2.5, and PM2.5 and FVC at the day of FVC measurement and the previous 6 days (lag 0 to 6 days). A total of 35,334 students aged 9 to 18 years were included in the study, and the mean exposure concentrations of ambient PM1, PM1–2.5, and PM2.5 for them were 47.4 (standard deviation [SD] = 21.3) μg/m3, 32.8 (SD = 32.2) μg/m3, and 80.1 (SD = 47.7) μg/m3, respectively. An inter-quartile range (IQR, 24 μg/m3) increment in exposure to PM1 was significantly associated with a lower FVC at lag 0 and lag 1 day (β = − 80 mL, 95% CI = − 119, − 42, and β = − 37 mL, 95% CI = − 59, − 16, respectively), and an IQR (54 μg/m3) increment in exposure to PM2.5 was significantly associated with a lower FVC at lag 0 and lag 1 day (β = − 57 mL, 95% CI = − 89, − 18, and β = − 34 mL, 95% CI = − 56, − 12, respectively) after adjustment for gender, age, body mass index category, residence, month of the survey, intake of eggs, intake of milk, physical activity, and screen time. No significant associations were observed for PM1–2.5. The inverse associations of PM1 and PM2.5 with FVC were larger in males, younger children, those overweight or obese, and those with insufficient physical activity levels. Short-term exposure to ambient PM1 and PM2.5 was associated with decreased FVC, and PM1 may be the primary fraction of PM2.5 causing the adverse pulmonary effects. Our findings emphasize the need to address ambient PM, especially PM1, pollution for affecting pulmonary health in children and adolescents. [ABSTRACT FROM AUTHOR]

Although nitrogen (N) and phosphorus (P) fertilization are important for maintaining the health and productivity of Leymus chinensis steppe, their impact on the abundance and community structure of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in this ecosystem is still unclear. We used the amoA gene as a molecular marker to monitor changes in AOA and AOB under low and high N and P fertilization and applied the resin-core technique to measure soil N mineralization. We found that the abundance of AOA based on amoA gene copies, ranging from 7.51 × 107 to 1.23 × 108 copies g−1 soil, was higher than that of AOB. Fertilization, especially high N and P, increased the number of amoA copies associated with AOB. AOA and AOB communities were dominated by Crenarchaeota and Proteobacteria, respectively. Fertilization decreased the relative abundances of Thaumarchaeota in the AOA community and Proteobacteria in the AOB community and increased the relative abundance of Ammonia_oxidizing_bacteria_ensemble. In N and P fertilization treatments, soil N transformation was closely related to AOB but not AOA. Soil ammonium N and nitrate N reshape the structure of ammonia oxidizers of AOB but not those of AOA on L. chinensis steppes. [ABSTRACT FROM AUTHOR]

Background: Delirium is common among critically ill patients, leading to increased mortality, physical dependence, and cognitive impairment. Evidence suggests non-pharmacological delirium prevention practices are effective in preventing delirium. However, only a few studies explore the actual implementation and its associated challenges among critical care nurses. Aim: To explore critical care nurses' perceptions of current non-pharmacological delirium prevention practices in adult intensive care settings, including delirium screening, early mobilisation, sleep promotion, family engagement, and sensory stimulation. Methods: A qualitative design adopting a thematic analysis approach. Semi-structured interviews with 20 critical care nurses were conducted in ten acute hospitals in mainland China. Results: Three themes emerged: (a) importance of family engagement; (b) influence of organisational factors, and (c) suggestions on implementation. The implementation of non-pharmacological delirium prevention practices was limited by a strict ICU visitation policy, lack of routine delirium screening and delirium training, light and noise disturbances during nighttime hours, frequent resuscitation and new admissions and strict visitation policy. Case-based training, adopting a sensory stimulation protocol, and family engagement may be enablers. Conclusion: ICU care routine that lacks delirium assessment and the strict family visitation policy made it challenging to implement the complete bundle of non-pharmacological practices. Resource deficiency (understaffing, lack of training) and ICU environment (frequent resuscitation) also limited the implementation of non-pharmacological practices. Clinicians could implement case-based training and sensory-stimulation programs and improve communication with family caregivers by instructing family caregivers to recognise delirium symptoms and delirium prevention strategies. [ABSTRACT FROM AUTHOR]

For the application of X80 pipelines in Northeast China, it is important to establish the correct cathodic protection (CP) potential. To achieve this, potentiodynamic polarization; electrochemical impedance spectroscopy (EIS); a slow strain rate test (SSRT); and a scanning electron microscopy (SEM) fracture morphology analysis were carried out for an X80 steel gas pipeline at several temperatures in Heilongjiang Province, China. The results show that the hydrogen evolution potential of X80 steel in soil at different temperatures was about −900 mV (vs. CSE). The generated hydrogen atoms can be adsorbed on the surface of the pipelines to reduce the surface energy, or they can be diffused into the substrate and accumulate to the critical concentration, inducing the decohesion between different structures and generating additional plastic deformation through dislocation motion. With the peak impedance potential as the minimum potential and the hydrogen embrittlement potential as the maximum potential, the CP potential of X80 steel in the soil at 30 °C, 45 °C, and 60 °C ranged from −900 mV to −1100 mV (vs. CSE), temperatures at which the X80 steel does not corrode or cause hydrogen embrittlement. [ABSTRACT FROM AUTHOR]

Despite the known influence of continuous cropping on soil microorganisms, little is known about the associated difference in the effects of continuous cropping on the community compositions of soil bacteria and fungi. Here, we assessed soil physicochemical property, as well as bacterial and fungal compositions across different years (Uncropped control, 1, 6, 11, 16, and 21 years) and in the watermelon system of a gravel mulch field in the Loess Plateau of China. Our results showed that long-term continuous cropping led to substantial shifts in soil bacterial and fungal compositions. The relative abundances of dominant bacterial and fungal genera (average relative abundance > 1.0%) significantly varied among different continuous cropping years (P < 0.05). Structural equation models demonstrated that continuous cropping alter soil bacterial and fungal compositions mainly by causing substantial variations in soil attributes. Variations in soil pH, nutrient, salinity, and moisture content jointly explained 73% and 64% of the variation in soil bacterial and fungal compositions, respectively. Variations in soil moisture content and pH caused by continuous cropping drove the shifts in soil bacterial and fungal compositions, respectively (Mantel R = 0.74 and 0.54, P < 0.01). Furthermore, the variation in soil bacterial and fungal composition showed significant correlation with watermelon yield reduction (P < 0.01). Together, long-term continuous cropping can alter soil microbial composition, and thereby influencing watermelon yield. Our findings are useful for alleviating continuous cropping obstacles and guiding agricultural production. [ABSTRACT FROM AUTHOR]

Potassium is the active element of potash fertilizer, its concentration determines the quality of the product. Self-absorption occurs in laser-induced breakdown spectroscopy (LIBS) analysis of potash, since potassium is the major element with a concentration that can reach the level of 95 wt.%. The present work simulated an online analysis of potassium in potash with a laboratory setup, LIBS spectra were recorded on 27 potash samples collected from a factory in Qinghai province in China with different potassium concentrations in the range from 90 to 97 wt.%. The self-absorption correction was applied to the spectra for K I 404.4 nm and K I 693.9 nm lines. Multivariate regression based on machine learning were processed with the self-absorption corrected spectra in order to get a better potassium determination performance compared to that with uncorrected spectra. The results show the effectiveness of self-absorption correction in the improvement of the analytical performance. The obtained multivariate regression model presents a satisfactory performance to fill the requirements of the aimed application of online and real-time analysis of potash on a product transportation belt in a production site with respect to the specific requirements of the related current national standards. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) plays an important role in the cycling and toxicity of heavy metals in aquatic systems. However, most studies have focused only on DOM in either water or sediments. This study aimed to analyze the source, composition, and structural characteristics of DOM in both surface water and bottom sediments of the Le'an River and its major tributaries. In addition, the potential ecological risks of three typical heavy metals (Cu, Pb, and Zn) were quantitatively evaluated based on the characteristics of DOM and in situ data. The results showed that sediment DOM is more aromatic and hydrophobic than surface water DOM. Although humic-like components dominated the DOM pool in both surface water and sediments, their sources were different. Surface water DOM is mainly autochthonous, while sediment DOM is controlled by both autochthonous and allochthonous sources. Risk prediction results based on DOM characteristics show that surface water has a higher potential risk of heavy metal release than sediments. Comprehensively considering the ecological risk of water and sediments, high-risk areas were found to be mainly distributed in the upper and middle reaches of the Le'an River. This distribution is attributable to the developed mining and smelting industries in these areas and consistent with the risk assessment results of measured concentrations of heavy metals. This study established a new technique for predicting the ecological risk of aquatic systems based on the characteristics of DOM in surface water and sediments. [ABSTRACT FROM AUTHOR]

Triosteum himalayanum, Triosteum pinnatifidum (Triosteum L., Caprifoliaceae, Dipsacales) are widely distributed in China while Triosteum sinuatum mainly occurrs in northeast China. Few reports have been determined on the genus Triosteum. In the present research, we sequenced 2 chloroplast genomes of Triosteum and analyzed 18 chloroplast genomes, trying to explore the sequence variations and phylogeny of genus Triosteum in the order Dipsacales. The chloroplast genomes of the genus Triosteum ranged from 154,579 bp to 157,178 bp, consisting of 132 genes (86 protein-coding genes, 38 transfer RNA genes, and 8 ribosomal RNA genes). Comparative analyses and phylogenetic analysis supported the division of Dipsacales into two clades, Adoxaceae and six other families. Among the six families, a clade of Valerianaceae+Dipsacaceae was recovered as a sister to a clade of Morinaceae+Linnaeaceae. A closer relationship of T. himalayanum and T. pinnatifidum among three species was revealed. Our research supported that Loniceraferdinandi and Triosteum was closely related. Zabelia had a closer relationship with Linnaea borealis and Dipelta than Morinaceae. The divergence between T. sinuatum and two other species in Triosteum was dated to 13.4 mya. [ABSTRACT FROM AUTHOR]

The discovery of a fossil Equus skull in Jinyuan Cave, Luotuo Hill, Dalian, is reported herein. The specimen was identified as Equus qingyangensis , based on the complexity of morphological features, and is considered to be as young as 1.2 Ma. Combined with the new finding, the known specimens of E. qingyangensis were reviewed and compared with other stenonid horse species in Eurasia. A skull previously reported as E. teilhardi , unearthed in the Nihewan Basin, is revised as E. qingyangensis. The recorded locations of E. qingyangensis findings are Bajiazui, Nihewan (s. s.), and the Jinyuan Cave. According to paleomagnetic data, mammalian fauna correlations, and significant environmental events, the ages of the Bajiazui and Nihewan (s. s.) localities are considered to be 2.1–1.7 Ma and correspond with the late Villafranchian faunae in Europe. Thus, based on the records, the temporal range of E. qingyangensis is 2.1–1.2 Ma. With climate change and exposure of the Bering Strait, the occurrence of E. qingyangensis in China was a significant biotic event. E. qingyangensis and another gracile species, E. stenonis , appeared and dispersed throughout Eurasia, and wolf-like canids and the large hyenid Pachycrocuta emerged during this period. Considering the roles equid and canid species played, we propose that this Equus – Canis occurrence represented a substantial biotic event during a series of major environmental and ecological changes. [ABSTRACT FROM AUTHOR]

In China, pharmacists have started to manage cancer pain at outpatient clinics. This retrospective study performed at a tertiary teaching hospital was aimed to evaluate the effects of a physician‐pharmacist joint clinic for cancer pain management. The study was performed between December 2016 and August 2019 and included 113 outpatients with moderate to severe cancer‐related pain. Patients were divided into two groups according to the clinic each patient visited: the physician‐pharmacist joint clinic (joint group, n = 59) or physician‐only clinic (usual group, n = 54). Brief Pain Inventory (BPI) and Morisky Medication Adherence Measure (MMAM) were used to collect data on pain intensity, interference and medication adherence. Pain Management Index (PMI) was also calculated. BPI, MMAM and PMI were assessed at baseline (patients' first visit, week 0) and week 4 follow‐up. The Chinese version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire‐Core 30 (EORTC QLQ‐C30) was used to assess patients' health‐related quality of life (HRQoL) at week 4. The primary outcomes were the improvement in pain intensity, adequacy of pain management and medication adherence. The secondary outcome was the improvement in HRQoL. At week 4, compared to the usual group, the BPI pain intensity categories except the pain right now were significantly lower in the joint group: worst pain, 4 (3‐7) vs 6 (4‐8), P =.020; least pain, 1 (0‐2) vs 2 (1‐3), P =.010; average pain, 3 (2‐4) vs 4 (2‐5), P =.023; pain right now, 2 (1‐3) vs 2 (0‐4), P =.796. For the seven pain interference categories, there were no significant improvements in the joint group (P >.05). Significantly more patients achieved adequate pain control in the joint group than the usual group ((P =.002). There was also a significant difference in medication adherence between the two groups (P =.001). There were no significant differences in HRQoL between the two groups. The study suggests that pharmacist participation in outpatient cancer pain management is associated with improvement of patients' pain control and medication adherence. [ABSTRACT FROM AUTHOR]

The relationship between natural hazard-induced disasters and macroeconomic growth has been examined widely on global and national scales, but little research has been focused on the subnational level, especially in China. We examined the impacts of natural hazard-induced disasters on the regional growth in China based on subnational panel data for the period from 1990 to 2016. First, we used the number of people affected and the direct economic losses as the measures of the scale of disasters. Then, we used the direct damages of meteorological disasters and earthquakes as disaster measures separately to examine the impacts of different disaster types. Finally, we performed intraregional effects regressions to observe the spatial heterogeneity within the regions. The results show that the adverse short-term effects of disasters is most pronounced in the central region, while the direct damage of disasters is a positive stimulus of growth in the whole of China. However, this stimulus is observed in a lagged way and is reflected differently—meteorological disasters in central and eastern China and earthquakes in western China are related to regional growth. The results demonstrate that the short-term macroeconomic impacts of these disasters in the three geographical regions of China largely depend on regional economic development levels and the disaster types. [ABSTRACT FROM AUTHOR]

A physical model was developed to quantify 4 He accumulation in gas reservoirs. Both radiogenic 4 He from external crustal flux and in situ 4 He production were calculated with this model. Considering the time-accumulation effect of 4 He, the formation time of a gas reservoir can be estimated. The proposed method was applied to Puguang gas reservoir in southwest China's Sichuan Basin, the formation time of which was estimated as 32.5 Ma, which corresponds to the Oligocene epoch and to the mid-Himalayan movement, and which is consistent with gas formation and accumulation history. This result indicates that the proposed model based on 4 He accumulation can be a useful tool for studying the formation time of gas reservoirs. [ABSTRACT FROM AUTHOR]

The mechanism of hydrogen sulfide (HS) generation plays a key role in the exploration and development of marine high-sulfur natural gas, of which the major targets are the composition and isotope characteristics of sulfur-containing compounds. Hydrocarbon source rocks, reservoir rocks, natural gases and water-soluble gases from Sichuan Basin have been analyzed with an online method for the content of HS and isotopic composition of different sulfur-containing compounds. The results of comparative analysis show that the sulfur-containing compounds in the source rocks are mainly formed by bacterial sulfate reduction (BSR), and the sulfur compounds in natural gas, water and reservoir are mainly formed by thermal sulfate reduction (TSR). Moreover, it has been shown that the isotopically reversion for methane and ethane in high sulfur content gas is caused by TSR. The sulfur isotopic composition of HS in natural gas is inherited from the gypsum or brine of the same or adjacent layer, indicating that the generation and accumulation of HS have the characteristics of either a self-generated source or a near-source. [ABSTRACT FROM AUTHOR]

The noble gases He and Ar are trace components in natural gas. Although their genesis is significantly different from that of hydrocarbon gases, they can provide key information on the accumulation and preservation of natural gas. In this paper, the relative and absolute abundances of He and Ar in lower Paleozoic shale gas samples from different areas of southern China were systematically analyzed, and the relationships between the concentrations of noble gases and the accumulation and expulsion of shale gas were evaluated. The evolution of He and Ar concentrations in shale gas system can be divided into three phases: the early accumulation stage, the hydrocarbon dilution stage and the preservation and enrichment stage. The generation of a large amounts of methane in the shale leads to the lowest relative concentrations of He and Ar in the hydrocarbon dilution stage. After that, the tectonic uplift causes the partial loss of the shale gas, and methane is no longer generated, but He and Ar are still produced. The concentrations of He and Ar present in shale gas are mainly controlled by the conditions of the preservation and enrichment stage. Tectonic uplift is the main reason for the loss of shale gas, and later uplift often results in higher gas content, which also leads to relatively low concentrations of He and Ar. The absolute abundance of residual Ar atm and the He/Ar ratio of a shale gas can indirectly reflect the preservation conditions of that shale gas. • No evidence was found of external sources of He or Ar in the shale gas systems. • The relative abundances of He and Ar can reflect the accumulation and expulsion process of the shale gas. • The He/Ar ratio is related to the time available for diffusion and the sealing capabilities of the shale system. [ABSTRACT FROM AUTHOR]

The hydrogen isotope composition of methane is an important parameter in natural gas research and provides complementary information to that provided by carbon isotopes. The stable hydrogen isotope ratios of 313 natural gas samples from six of China’s sedimentary basins are used to evaluate the factors that influence the stable hydrogen isotopic composition of methane. An important factor is the δD of organic matter in hydrocarbon source rocks, which is influenced by the sedimentary environment and type of organic matter. Natural gases generated from sapropelic organic matter have relatively less negative δ D CH 4 , while natural gases generated from humic organic matter have relatively more negative δ D CH 4 . The other factor is thermal maturity. Increased thermal maturity leads to δ D CH 4 becoming less negative and there exists a two stage linear relationship between the δ D CH 4 and the logarithm of the vitrinite reflectance ( R o) value for natural gases generated from type III kerogen. The third factor is the environmental conditions of the aqueous medium in the original depositional environment and after sedimentation. Elemental hydrogen from water participates in biochemical processes as organisms grow and is exchanged during the sedimentation and diagenesis of organic matter as well as maturity process of kerogen to generate gases. The influence of the aqueous medium on δ D CH 4 after formation of natural gases can be ignored. Among these factors, the aqueous medium is the key constraining factor. The δ D CH 4 in natural gases can be combined with the use of stable carbon isotopic composition to identify the origins of natural gases and to aid gas-source correlations. [ABSTRACT FROM AUTHOR]

Three-North Shelterbelt Forest (TSF) program, is one of six key forestry programs and has a 73-year construction period, from 1978 to 2050. Quantitative analysis of the carbon sequestration of shrubs in this region is important for understanding the overall function of carbon sequestration of the forest and other terrestrial ecosystems in China. This study investigated the distribution area of shrubland in the TSF region based on remote sensing images in 1978 and 2008, and calculated the carbon density of shrubland in combination with the field investigation and previous data from published papers. The carbon sequestration quantity and rate from 1978 to 2008 was analyzed for four sub-regions and different types of shrubs in the TSF region. The results revealed that: 1) The area of shrubland in the study area and its four sub-regions increased during the past thirty years. The area of shrubland for the whole region in 2008 was 1.2 × 10 ha, 72.8% larger than that in 1978. The Inner Mongolia-Xinjiang Sub-region was the largest shrubland distribution area, while the highest coverage rate was found in the North China Sub-region. 2) In decreasing order of their carbon sequestration, the four types of shrubs considered in this study were Hippophae rhamnoides, Caragana spp., Haloxylon ammodendron and Vitex negundo var. heterophylla. The carbon sequestration of H. rhamnoides, with a maximum mean carbon density of 16.5 Mg C/ha, was significantly higher than that of the other three species. 3) The total carbon sequestration of shrubland in the study region was 4.5 × 10 Mg C with a mean annual carbon sequestration of 1.5 × 10 Mg C. The carbon density in the four sub-regions decreased in the following order: the Loess Plateau Sub-region, the North China Sub-region, the Northeast China Sub-region and the Inner Mongolia-Xinjiang Sub-region. The paucity of studies and data availability on the large-scale carbon sequestration of shrub species suggests this study provides a baseline reference for future research in this area. [ABSTRACT FROM AUTHOR]

By means of the vitrinite reflectance and U-Th/He dating of apatite and zircon in cutting samples from the T x-K j formations in the Yuanba (元坝) area of Northeast Sichuan (四川) Basin, a correlation has been established between the He-derived age and depth/temperature in this area assuming helium closure temperature of apatite in this area being 95 °C. Mesozoic strata (T x-K j) experienced helium closure temperature of apatite approaching 95 °C, but didn't reach the helium closure temperature of zircon (ca. 170-190 °C) although some reached the highest palaeogeothermal temperature of about 170 °C. The Mesozoic strata in the Yuanba area experienced an important uplift and denudation during Paleogene-Neogene periods (0.2-36.4 Ma), the erosion rate being about 109.9 m/Ma. The K j Formation and overlying strata experienced a maximum denudation loss of about 4 000 m. Geotemperatures gradually fell to the helium closure temperature of apatite and then fell further to the current temperature. The thermal evolution history of this area indicates that the maximum palaeogeothermal temperature of Mesozoic strata was close to 170-190 °C, prior to the strata being uplifted. During the period between 176 and 36 Ma, the palaeogeothermal temperature fell to 95-170 °C, and after 36 Ma, it continued to fall to the present geotemperature of less than 95 °C. [ABSTRACT FROM AUTHOR]

Using high pressure and geological condition simulation vessels, we conducted hydrous pyrolysis experiments of kerogen, solid bitumen and liquid hydrocarbons in southern China in order to study the processes of gas generation and derive geochemical indicators of gas genesis under approximate pressure and temperature. The results indicate that gas generation productivity of different marine material decreased in the order of crude oil (light oil and condensate), dispersed soluble organic matter (solid bitumen and heavy oil), and kerogen. Under identical temperature-pressure regimes, pyrolysates derived from kerogen and dispersed soluble organic matter display drastically different geochemical characteristics. For example, the $\delta ^{13} C_{CO_2 } - \delta ^{13} C_1 $ values of gaseous products from dispersed soluble organic matter are greater than 20‰, whereas those from kerogen are less than 20‰. The δC values of pyrolysates from different marine hydrocarbon sources generally increase with pyrolysis temperature, but are always lower than those of the source precursors. The δC values of ethane and propane in the pyrolysates also increase with increasing pyrolysis temperature, eventually approaching that of their sources, at peak hydrocarbon generation. At high-over mature stages, the δC values of ethane and propane are often greater than those of their sources but close to those of coal gases, and thus become ineffective as gas genetic indicators. Ln(C/C) can clearly distinguish kerogen degradation gas from oil cracking gas and Ln(C/C)-( δC− δC) can be an effective indicator for distinguishing oil cracking gas from dispersed soluble organic matter cracking gas. [ABSTRACT FROM AUTHOR]

High resolution carbon isotope analyses of carbonate and organic carbon from Meishan, South China showed that the variation of δC is marked by three large positive excursions during the Changhsingian (end-Permian). Carbon isotope stratigraphy during this stage shows three cyclic intervals in δC, with two cycles corresponding to the lower (Paleofusulinid minima Zone) and one corresponding to the upper Changhsingian (P. sinensis Zone). The large positive δC excursions indicate episodes of enhanced burial of isotopically light organic carbon, presumably in response to deep-water anoxia episodically extending into shallow water with the rise of sea level. The organic carbon during the Changhsingian is distinguished into two groups, and the δC of each group parallels (separately) the more detailed profile of δC, strongly showing that the values of fractionation ΔC remain relatively constant, with only two intervals with anomaly. The enhanced fractionation ΔC with large negative δC excursions apparently indicates significant inputs from sulfide-oxidizing bacteria and green sulfur bacteria, notably at bed 24 just predating mass extinction. Our evidence appears to support that the extended euxinic water is possible for the main pulse of mass extinction at the end-Permian. [ABSTRACT FROM AUTHOR]

Based on the pyrolysis products for the Jurassic low-mature coal under programmed temperature, and chemical and carbon isotopic compositions of natural gas from the Kuqa Depression, the genetic origin of natural gas was determined, and then a gas filling model was established, in combination with the geological background of the Kuqa Depression. The active energy of CH4, C2H6 and C3H8 was gotten after the data of pyrolysis gas products under different heating rates (2°C/h and 20°C/h) were fitted by the Gas Oil Ratio (GOR) Isotope Model soft. When the frequency factor (Af) was chosen as 1×1014, the active energy of CH4, C2H6 and C3H8 was 58 kcal/mol, 57 kcal/mol and 54 kcal/mol, respectively. The distributive ranges of the δ13C1, δ13C2 and δ13C3 values for the pyrolysis gas products are -35.9‰ to -30.7‰, -26.2‰ to -21.3‰ and -26.4‰ to -22.7‰, respectively. All of the natural gases from the Kuqa Depression are dominated by hydrocarbon gases, with the high gas dryness (C1/C1-4) at the middle and northern parts of the depression and the low values at both east and west sides and the southern part. The carbon isotopes of methane and its homologs as a typical coal-type gas are enriched in 13C, and the distributive range of the δ13C1, δ13C2 and, δ13C3 value is -32‰ to -38‰, -22‰ to -24‰ and -20‰ to -22‰, respectively, with the carbon isotopes of gaseous alkanes being less negative with the carbon number. With the ethane being enriched in 13C the increasing tendency of the geological reserve of natural gas in the Kuqa Depression is observed. This observed change is consistent with the results of pyrolysate gas yield of coal as a potential gas source in the Kuqa Depression, suggesting natural gas was thermally derived from the humic organic matters and the carbon isotopes of gaseous alkanes would coarsely predict the geological reserve of gas in the Kuqa Depression. Through the simulation of kinetic processes of gas generation for the Jurassic coal in the Kuqa Depression, the gas in the Kela 2 gas field would get the threshold of gas expulsion after 27 Ma, be expelled out of source rocks as 'pulse action', and then filled in the gas reservoir. The peak gas-filling history took place during the past 2 Ma. [ABSTRACT FROM AUTHOR]

The age-accumulation effect of Ar in hydrocarbon source rocks was discussed in accordance with the decay law of radioactive elements. In terms of the mean values of Ar/Ar, the old Sinian gas reservoirs (mean values of Ar/Ar: 7009) were definitely distinguished from the Permian gas reservoirs (mean values of Ar/Ar: 1017) in Weiyuan, Sichuan Province, and the gas source of the Permian gas reservoir (mean values of Ar/Ar: 5222) in well Wei-7 with the Weiyuan structure is defined as the Sinian system. Based on the values of Ar/Ar, the coal-type gases (The source rocks are of the C-P system; mean values of Ar/Ar: 1125) are definitely distinguished from the oil-type gases (The source rocks are of the Tertiary system; mean values of Ar/Ar: 590) in the Tertiary reservoirs of the Zhongyuan Oilfield. Besides, Ar/Ar values also have a positive effect on the oil-source correlation of oil reservoirs in ancient hidden mountains. According to the crust-mantle interchange information reflected by He/He values, petroliferous provinces in China can be divided into three major tectonic regions. (1) The eastern active region: The crust-mantle volatile matter exchanges actively, and the He/He values are mainly around 10, partly around 10. (2) The central stable region: The He/He values are all around 10. (3) The western sub-stable region: The He/He values are mainly around 10, and around 10 on the edges of the basins. Helium contents of some gas wells in China's eastern petroliferous region reach the industrial abundance (He≈0.05%-0.1%), the He/He values reach 10, and the equivalent values for the mantle-source components in helium gas can reach 30%-50%. As viewed from this, a new type of crust-mantle composite helium resources has been proposed. Geneses of some CO gas reservoirs in the east of China and some issues concerning mantle-source methane were discussed in the light of the helium and carbon isotopes of CO and CH in natural gases. In the discussion on helium isotopic characteristics of inclusions in the reservoirs, it was discovered that the He/He values are close to those in natural gases. That is to say, this phenomenon is related to regional tectonism. The He/He, CO/He and CH/He data were used to discuss the tectonic activities of fault zones in a certain number of regions in China. [ABSTRACT FROM AUTHOR]

Variations in the stable carbon isotope signature of marine carbonate rocks (δ13C carb) are utilized as an indicator for changes in depositional environment and tracers of diagenetic alteration. Various petrologic (textural changes) and geochemical indicators (trace elements) have been used to evaluate the effect of diagenetic alteration on the δ13C carb signature. However, how diagenetic processes involving interactions between organic matter and minerals impact the δ13C carb records of marine carbonate rocks has not been investigated thoroughly. In this study, systematic stable carbon (δ13C carb) and oxygen (δ18O carb) isotope analyses were conducted on marine carbonates from the Middle Ordovician Majiagou Formation in the Ordos Basin, China to evaluate secondary overprint of the primary δ13C carb record. 496 carbonate samples from the gas reservoir (potential gas source rock) were selected from one well located in the natural gas exploration target—mid-east part of the Ordos Basin. A depleted δ13C carb excursion (i.e., a shift to more negative values) occurred in the 100 m-thick anhydrite-bearing carbonate sequence of this formation. The δ13C carb and δ18O carb values for the whole rock vary from −10.9‰ to 1.8‰ and −11.5‰ to −4.0‰, respectively. The calcite veins and vug-filling calcites also have depleted carbon isotope signature ranging between −21.1‰ and −4.4‰. The secondary calcites observed under the microscope were generated by the conversion from isotopically depleted organic matter and resulted in the depleted δ13C carb signature. The commonly occurring thermochemical sulfate reduction in the study area and the degradation of potentially enriched carboxylic acid salts in anhydrite-bearing carbonate setting are major factors contributing to the depleted δ13C carb values. The conversion from organic carbon to inorganic carbon through organic matter-involved diagenetic processes plays a significant role in explaining the genesis of depleted δ13C carb excursions in deeply buried marine carbonate sequences. [Display omitted] • High-amplitude depleted δ13C carb signatures were first found to occur in the Middle Ordovician carbonate sequence. • Diagenetic processes involving organic matter impacted the original δ13C carb record. • Organic-origin calcites generated by TSR resulted in the depleted δ13C carb signatures. [ABSTRACT FROM AUTHOR]

Natural gases of shallow reservoirs with the carbon isotopic compositions of methane ranging from -50‰ to -60‰ (PDB) were considered as mixed gases of biogenic and thermogenic origins previously and some of them were considered as low-mature (or low temperature thermogenic) gases lately. In this paper natural gases with the carbon isotopic compositions of methane in the above range were identified using the molecular and stable carbon isotopic compositions of methane, ethane and propane. The mixed gases of biogenic and mature thermogenic origins display the characteristics of δ 13C1 ranging from -50‰ to -60‰, δ 13C2 > -35‰, Δ values (δ 13C3 - δ 13C3) < 5‰ and C1/ΣC2+ ratios < 40. Immature to low-mature gases display the characteristics of δ 13C1 ranging from - 50‰ to - 60‰, δ 13C1 < -40‰, Δ values (δ 13C3 - δ 13C3) > 7‰, and C1/ΣC2+ ratios >60. [ABSTRACT FROM AUTHOR]

Helium is an exhaustible natural resource and the main commercial helium was separated from helium-rich natural gas. The helium in the sedimentary basin is mainly the radiogenic origin of crustal rocks with high level of uranium and thorium. Data from 242 natural gas samples were used to investigate the distribution and formation mechanism of helium-rich gases in the Sichuan Basin of China. All gas samples show remarkably low 3He/4He ratios with ranging from 0.002 to 0.05 Ra, which represent typical crustal helium. The Weiyuan gas pool in the southern Sichuan Basin possesses high levels of helium (1500–18770 ppm, average 2785.7 ppm) in Precambrian and Cambrian strata. A positive relationship were observed in the helium and nitrogen contents increased with reservoir layer age for all Weiyuan gas samples. Presinian granite was considered as the main helium source for the Weiyuan gas pool. Gaoshiti–Moxi and Weiyuan gas pools belonged to the same ancient gas pool before the Late Cretaceous, but the helium abundance of Gaoshiti–Moxi gas pool is relatively low (200–891 ppm). The change of pressure and fracture system caused by the uplift of Weiyuan structure in the Himalayan orogenesis led to the helium accumulation and enrichment of Weiyuan gas pool. The shale of the Silurian Longmaxi Formation has high contents of uranium and thorium and generated a large amount of helium while forming large quantities of hydrocarbon gases. Generally, the helium abundance of shale gases and conventional gases generated from the Longmaxi Formation ranges from 63 to 1500 ppm and some of the gas pool are sufficient for commercial helium resource exploitation. Therefore, the relative quantities of helium and hydrocarbon gases are act as a key factor influencing the formation of helium-rich natural gas reservoirs. • Helium in the sedimentary basin is mainly the radiogenic origin. • Helium-rich gas is generally the crust-derived heterogenous type. • Presinian granite was the main source of helium in the Weiyuan gas field. [ABSTRACT FROM AUTHOR]

Helium is an important, scarce, and strategic resource that is critical to national security and advanced technology development. Although helium originates from mantle degassing and the radioactive decay of uranium (U) and thorium (Th) in minerals, commercial helium resources are primarily derived from natural gas reservoirs with He concentrations higher than 1000 ppm. The gas geochemistry characteristics of 920 natural gas samples from nine petroliferous basins in China were used to classify and discuss the enrichment mechanisms of helium. Helium-bearing natural gas reservoirs can be divided into the following three types: basement source-migration-rich accumulation, self-generating and self-preserving, and crust–mantle complex types. The basement source-migration-rich accumulation, which is the most common type of proven helium-rich natural gas reservoir, occurs primarily in inherited anticlines and dome traps located on basement uplifts. Ancient shale systems demonstrate the potential to form helium-rich shale gas that belongs to the self-generating and self-preserving type. Crust–mantle complex helium-rich natural gas reservoirs develop in petroliferous basins in active magmatic–tectonic areas. The origins of helium and hydrocarbon gas are different, but the entrainment of helium during hydrocarbon gas accumulation is a key factor influencing the formation of helium-rich natural gas reservoirs. The nitrogen concentration in helium-rich gas samples is often extremely high, indicating that the nitrogen and the helium are derived from the same source rock or both are extracted from water by migrating gas. • Helium-rich gas includes basement source-migration-rich accumulation, self-generating and self-preserving, and crust–mantle complex types. • Exsoluion gathering of underground dissolved helium is the key mechanism of helium enrichment. • High-quality matching between helium and natural gas is crucial for the helium-rich gas accumulation. [ABSTRACT FROM AUTHOR]

Abstract: The Ordos basin, the second largest natural gas producing basin in China, is one of the most tectonically stable sedimentary basins favorable to natural gas generation and preservation. The origin and potential source of the Jingbian gas field, one of the five giant gas fields in the basin containing the Ordovician paleo-weathering crust as reservoir strata, remains unclear. The question is whether gas is generated from Carboniferous–Permian coal measures or Ordovician carbonates. This study provides abundant gas geochemical evidence which clarifies its origin and source. Among 82 natural gas samples collected from the Ordovician paleo-weathering crust in the Jingbian gas field, C1–C4 gaseous hydrocarbons are dominant with low amounts of non-hydrocarbons (CO2, H2S and N2). The content of C1–C4 ranges from 79.26 to 99.93% with a gas dryness (C1/C1−4) of 0.981–0.999, suggesting that natural gases are dry and possibly originate from a high to over-mature source. The carbon isotopic compositions of methane and its homologues in natural gases from the Ordovician paleo-weathering crust vary widely, with δ13C1, δ13C2 and δ13C3 values of −38.9‰ to −29.1‰, −37.5‰ to −22.2‰ and −30.0 to −20.9‰, respectively. The δ13C2 and δ13C3 values in the Jingbian gas field are much more negative than those of typical coal-type gas in Sulige, Wushenqi, Yulin, Daniudi, and Kela2 gas fields. The carbon isotopic signature suggests that the natural gas in the Ordovician paleo-weathering crust in the Jingbian gas field most likely originates from Ordovician carbonates containing sapropelic organic matter. The measured δD values of methane range from −177 to −155‰ and support our hypothesis of the natural gases originating from marine sapropelic organic matter. The thermal maturity of the natural gases in the Ordovician paleo-weathering crust is at a high- to over-mature stage, suggesting that the gases originated from secondary cracking of oil and gas at high temperature and pressure. Thermochemical sulfate reduction (TSR) might partially play a role in the alteration of gas dryness and δ13C1 in those areas where gypsum is present as an effective cap rock. Mixing of high- to over-mature secondary cracking gas from the Ordovician source and coal-type gas from Carboniferous–Permian coal in the Jingbian gas field is minor. [Copyright &y& Elsevier]

• An Intramolecular isotopic study was conducted on natural gases from the Santanghu Basin, China. • Intramolecular carbon isotopic rollover and a decrease in δ13C terminal occur between 0.46 and 0.50 %R o. • These effects can be explained by kinetic effects in the thermal cracking of kerogen with a low proportion of branched chains. • A new approach for elucidating the chemical structure of kerogen is proposed. An intramolecular isotopic study was conducted on natural gases from the Santanghu Basin in China. Propane samples spanned a wide range of Δ C-T (δ13C central -δ13C terminal) values from –8.4 to 8.5 ‰, δ13C central and δ13C terminal values varied from –37.3 to –25.8 ‰ and –35.7 to –28.9 ‰, respectively. During thermal maturation, the position-specific carbon isotopic composition of propane shifted from δ13C central < δ13C terminal to δ13C central > δ13C terminal , and the δ13C terminal decreased by 6.8 ‰ within a R o range of 0.46–0.50 %. The intramolecular carbon isotopic rollover and a decrease in δ13C terminal with a slight increase in maturation could be explained by kinetic effects in thermal cracking of kerogen with a low proportion of branched chains. As isomeric groups were rapidly exhausted, propane generation pathway rapidly changed and primary kinetic isotope effect completely shifted from central carbon position to terminal carbon positions in propane. These changes increased carbon isotope fractionation at terminal carbon positions, thereby reducing δ13C terminal values and shifting δ13C central < δ13C terminal to δ13C central > δ13C terminal within a small maturity range. This work demonstrated that position-specific isotope distribution of propane can be applied to elucidate the chemical structure of kerogen. [ABSTRACT FROM AUTHOR]

To block transmission of measles, the China Ministry of Health endorsed the "2006–2012 National Measles Elimination Action Plan (NMEAP)" on November 11, 2006, while no published studies used mathematical models to assess the impact of this action. Also, the problem of residuals autocorrelation due to auto-correlated infectious disease data is often ignored in practice. Based on monthly counts of measles in 31 Chinese provinces during 2004–2016, a spatiotemporal auto-correlated mixed model was developed to assess the intervention effects over 10 years after the NMEAP, after controlling for seasonality and time-varying socioeconomic and meteorological factors. The first-order autoregression dynamic relationship was used to adjust the bias of conditional covariance in Quasi-likelihood function due to temporal autocorrelation and the spatial autoregressive term was used to capture the neighbor effects of adjacent provinces. There were a similar seasonal pattern and spatial differences of measles incidence among provinces, yet the spatiotemporal pattern was diminished after the intervention. The introduction of the NMEAP was associated with a reduction of 51.03% [excess risk (ER%) = −51.03%, 95% CI: −62.32% to −36.37%] in measles morbidity on average during the 10-year intervention period. The intervention effect varied with time. The significant effect was observed 15 months after the intervention onset, and then gradually increased to a stable level, but was weakened slightly after 2012. The effect of birth rate and meteorological factors on measles morbidity reduced after the NMEAP. There was clear evidence that prominent progress towards a goal of measles elimination had been achieved after the intervention, while the resurgence after 2012 indicated the goal for measles elimination by 2012 had not been reached. [ABSTRACT FROM AUTHOR]

The taxonomic and phylogenetic positions of spiral horned antelope Spirocerus have been controversial since its first discovery in Central Asia and with the discovery of more and more fossil specimens and localities in Central and East Asia. New material of Spirocerus wongi were recently identified from the fossil specimens collected from Nihewan Formation at Shuichongkou along Xinyaozi ravine of Tianzhen County, Shanxi Province in North China. Taxonomic study shows that three species of Spirocerus can be regarded valid, i.e. S kiakhtensis , S. wongi and S. peii. Phylogenetic analyses indicates that they form a distinct clade closer to Bovinae than to Antilopinae, and Spirocerus can be placed in Bovinae rather than in Antilopinae. S. kiakhtensis might evolve from a Gazellospira -like form migrated from Europe to Central Asia in the Pliocene, then dispersed into northern China in the Early Pleistocene and evolved into S. wongi and S. peii. S. wongi dispersed further into northwestern and central China in the Early Pleistocene and disappeared in the Middle Pleistocene. S. peii ranged only in northern China in the Middle Pleistocene. After dispersion into northwestern and northeastern China in the Late Pleistocene, S. kiakhtensis disappeared near the end of the Pleistocene. [ABSTRACT FROM AUTHOR]

Many fossil Elaphurus have been discovered in East Asia and some in Central Asia since the discovery of the first fossil E. bifurcatus of the genus from Nihewan Basin in the 1920s. Some of them are well preserved, but some others are fragmental and it makes some identifications doubtful. Two Elaphurus were identified in recent study based on the unstudied material of fossil deer unearthed from Taijiaping, Tianzhen, Shanxi Province in North China. The taxonomy of Elaphurus was consequently discussed and it is recommended to classify the genus into four species with eight subspecies. Elaphurus davidianus predavidianus subsp. nov. distributed in North China and Taiwan in the Early Pleistocene. E. davidianus tamaensis is a geographic subspecies of the Early Pleistocene in Japan. E. d. menziesianus derived from E. d. predavidianus and distributed in North, Northeast and East China including Taiwan, as well as in Japan, from the Middle Pleistocene to the Holocene and E. d. davidianus restricted in North and East China probably since recent thousands years ago. E. bifurcatus bifurcatus and E. b. shikamai existed in the Early Pleistocene in North China and Japan respectively. The probable ancestor of E. bifurcatus is Elaphurus eleonorae from the Early Pleistocene of Kuruksay, Tadjikistan in Central Asia. The Early Pleistocene E. chinnaniensis chinnaniensis and E. c. lantianensis ranged in North China only and with dubious generic status. [ABSTRACT FROM AUTHOR]

An intramolecular isotopic study was conducted on natural gases from the Turpan-Hami Basin of China. The set of natural gases exhibits larger δ13C values of the terminal position compared with those at the central position of propane, with Δ C-T (δ13C central -δ13C terminal) values ranging from −3.8‰ to −0.7‰. During the thermal cracking of kerogen, the primary kinetic isotope effect is on the terminal carbon position to generate n -propyl radicals and on the central carbon position to produce i -propyl radicals. Therefore, distinct reaction pathways significantly influence the position-specific carbon isotope distribution in thermogenic propane. In the early stage of maturation, propane is preferentially generated from the i -propyl radicals by capturing hydrogen atoms owing to the lower dissociation energies of i -propyl radicals cleavage from kerogen compared with those of n -propyl radicals, resulting in larger δ13C values in the terminal position compared with those at the central position of generated propane. The position-specific 13C isotope composition of propane could provide new insights into revealing the generation mechanism of natural gas in the geological period at the atomic level. • Propane with early maturation exhibits larger δ13C values in the terminal position than those at the central position. • Propane can be preferentially generated from the i -propyl radical reaction at the early maturation stage. • Decompositions of the branched aliphatic chains structure contribute to the low-mature gas generation in the Turpan-Hami Basin. [ABSTRACT FROM AUTHOR]

Short-term exposure to ambient PM 2.5 and PM 10 is associated with increased risk of mortality and hospital admissions for stroke. However, there is less evidence regarding the effect of exposure to PM 1 on stroke incidence. We estimated the incidence risk of stroke and the attributable fractions related to short-term exposure to ambient PM 1 , PM 2.5 and PM 10 in China. County-specific incidence of stroke was obtained from health statistics in years 2014–2019. We linked county-level mean daily concentrations of PM 1 , PM 2.5 and PM 10 with stroke incidence. We used the time stratified case-crossover design to estimate the associations between stroke incidence and exposure to PM 1 , PM 2.5 and PM 10. We also estimated the disease burden fractions attributable to PM 1 , PM 2.5 , and PM 10. The study included a total of 2,193,954 stroke, from which 1,861,331 were ischemic and 332,623 were hemorrhagic stroke. PM 1 , PM 2.5 , and PM 10 levels were associated with increased risks of total stroke and ischemic stroke at when assessing the associations in exposure at lag0−4 days. The increase of 10 μg/m3 in PM 1 , PM 2.5 , and PM 10 was associated with total stroke, and the relative risks were 1.012 (95% confidence interval: 1.008, 1.015), 1.006 (1.004, 1.007) and 1.003 (1.002, 1.004), while the associations with ischemic stroke were 1.013 (1.010, 1.017), 1.006 (1.005, 1.008) and 1.003 (1.002, 1.004), respectively. There was no significant association between PM and risk of hemorrhagic stroke. The attributable fractions of total stroke were 6.9% (5.1%, 8.5%), 5.6% (4.2%, 6.8%) and 5.6% (3.9%, 7.1%) for PM 1 , PM 2.5 , and PM 10 , respectively. PM 1 showed a stronger association with stroke, with a larger attributable fraction of outcomes, than PM 2.5 and PM 10. Clean air policies should target the whole scope of PM, including PM 1. • Exposure to PM 1 , PM 2.5 and PM 10 at lag0–4 day may lead to ischemic stroke. • PM 1 has stronger association with ischemic stroke incidence than PM 2.5 and PM 10. • Social deprivation may strengthen the PM-stroke association. • Future air clean policies should cover the scope of PM 1. [ABSTRACT FROM AUTHOR]

Limited evidence exists regarding the effect of exposure to ambient particle matters with aerodynamic diameter ≤1 μm (PM 1) in a short-term on blood pressure (BP) in the pediatric population. This study aims to examine the association between short-term exposure to ambient PM 1 on BP in children and adolescents. Population data were obtained from a large cross-sectional survey from 102 schools in Shandong Province, China. Daily air pollution data were collected, and individual exposure level was assigned based on coordinates of school addresses. Distributed lag non-linear models incorporated with a linear mixed model were used. A total of 35241 students aged 9–18 years were included in the study, and the mean values of PM 1 , particle matters with aerodynamic diameter ≤2.5 μm (PM 2.5), and ≤10 μm (PM 10) at the schools during the study period were 50.8 (SD = 7.2) μg/m3, 75.5 (SD = 14.7) μg/m3, and 138.9 (SD = 25.9) μg/m3, respectively. We found that per 10 μg/m3 increment in a cumulative exposure of PM 1 at lag 0 and lag 1 day was significantly associated with a higher systolic BP (SBP, β = 1.46 mmHg), diastolic BP (DBP, β = 1.20 mmHg, 95% CI = 0.52 to 1.88), mean arterial pressure (MAP, β = 1.28 mmHg, 95% CI = 0.61 to 1.96), and pulse pressure (PP, β = 0.65 mmHg, 95% CI = 0.14 to 1.16), after adjusting for other air pollutants and individual covariates (including sex, age, BMI, residence, month of the survey, intake of eggs, intake of milk, physical activity, and screen time). The above associations were stronger in magnitude than for PM 2.5 - and PM 10 -related associations. The associations of PM 1 with SBP, DBP, MAP, and PP were stronger among females, younger children, those overweight or obese, and those with insufficient physical activity levels. In conclusion, the susceptible window of short-term exposure to ambient PM 1 , PM 2.5 and PM 10 on BP levels for children and adolescents are lag 0 and lag 1 day, with PM 1 exhibiting a stronger association. Future interventions should be conducted to reduce the impact of PM exposure, especially PM 1 , on health in children and adolescents. • Exposure to PM 1 , PM 2.5 and PM 10 at lag 0 and 1 day may affect blood pressure level. • PM 1 has stronger association with blood pressure level than PM 2.5 and PM 10. • Future air clean policies should cover the scope of PM 1. [ABSTRACT FROM AUTHOR]

Abstract: Whether there are terrestrial responses to the Oceanic Anoxic Events (OAEs) remain enigmatic. In this paper, we report a case study in the Lower Cretaceous continental and transitional sequences of coastal southeastern China. It may represent the first late Aptian to Albian terrestrial carbon isotope record from China. Several organic-rich black shale and grayish black mudstone horizons were found to develop widely in the coastal southeastern China during the period from 113±3Ma to 99±3Ma, when the Cretaceous OAEs were recorded primarily in marine sequences. Organic carbon isotope (δ13Corg), total organic carbon (TOC), and total nitrogen (TN) were analyzed for the black shales from two sections, i.e., the Shipu transitional and Chong'an continental sections. Five negative δ13Corg excursions can be recognized for both the sections, termed as SI–SV and CI–CV events for the Shipu (S) and Chong'an (C) sections, respectively. Correlations between δ13Corg, TOC and N/C ratio suggest that the SI–SIII and CI–CIII events might have been caused by global factors, i.e., the OAE1b event based on analogs to typical OAE1b reported in the Tethyan and Pacific basins. They archived the terrestrial carbon isotope response to the OAE1b accompanied with a disturbance of carbon isotope in carbon reservoir of the global ocean–atmosphere system under a warm and humid climate. [Copyright &y& Elsevier]

Analysis of redox conditions of lake water is of great significance to the reconstruction of sedimentary environments. However, previously established threshold values of redox-sensitive element proxies may not be directly applicable to various study areas even with some degree of calibration. The present study of the Permian Lucaogou Formation (P 2 l), Santanghu Basin, re-evaluates and calibrates commonly used redox proxies, including bimetal ratios, the C–S–Fe–P system, and proxies based on U abundances. Specifically, we rely on the compound covariation theory of proxies proposed by previous researchers within the redox framework according to three key redox thresholds (T1: suboxidized/subreduced boundary, T2: middle of subreduced zone, and T3: suboxic/euxinic boundary) and organic/inorganic geochemical data. The results show that the fixed thresholds of widely used redox proxies, including bimetal ratios, are not fully applicable to the studied succession. Reassessment of the use of bimetal ratios based on covariation theory suggests that the V/Cr, V/(V + Ni), TOC/P, and Fe/Al ratios are especially useful to redox analysis of the P 2 l succession whereas the Ni/Co, Ni/V, (Cu + Mo)/Zn, U/Th, and U auth proxies yield spurious results. It is important to point out, however, that the threshold values of those proxies that have yielded useful results cannot be used without calibration. Therefore, those redox proxies used in our investigation of the P 2 l succession have been re-calibrated based on the proxy covariation theory. For example, V/(V + Ni) values of T1, T2, and T3 thresholds of approximately 0.78 differ from the fixed threshold values established by previous investigations, suggesting that avoiding erroneous redox interpretations will require calibration of the thresholds. Other redox proxies display a similar need for calibration. Deposits of the P 2 l, by virtue of small variations among the three thresholds, record a complex history of rapid transitions from suboxic to euxinic conditions. • Redox conditions of the Permian Lucaogou Formation (P 2 l) were revealed in detail. • The effectiveness of redox proxies commonly used in the P 2 l was reassessed. • Specific threshold values of redox proxies for the P 2 l were established. • Redox proxy with fixed threshold cannot be applied to other area without calibration. [ABSTRACT FROM AUTHOR]

Fourteen gases and their associated oils were collected at the surface from production wells in the Shahejie Formation, Dongying Formation, and Archean in six zones around the Qingshui Sub-sag of the Liaohe Depression, Bohai Bay Basin. The molecular compositions and carbon and hydrogen isotopic compositions of natural gas were measured. The origin, migration, accumulation, and secondary alteration of natural gas were studied based on the lateral and vertical comparison of natural gas geochemical characteristics. The natural gases include humic-type (δ13C 2 > −29.0‰, δ13C 1 > −43.0‰), sapropelic-type (δ13C 2 < −29.0‰, δ13C 1 > −43.0‰), and secondary microbial (δ13C 1 of −48.5‰, C 1 /(C 2 +C 3) of 46.3, δ13CO 2 of −1.5‰) gases. The humic-type and sapropelic-type gases were derived from the source rocks in the third and fourth members of the Shahejie Formation, respectively. The humic-type gases dominate. The biodegradation level of natural gas in the study area varies, and biodegraded gases are characterized by high Δ13C(C 3 –C 2), low C 3 /C 2 , and low C 3 /iC 4 and are associated with biodegraded oils. The vertical migration of natural gas in the west and east of the Qingshui Sub-sag is limited. There are good additional exploration prospects for humic-type gas, derived from high-maturity source rocks of the third member of the Shahejie Formation in the deep layers (depth >4.5 km) of the Qingshui Sub-sag. Secondary microbial gas is a potential exploration target in the shallow layers (depth <2.5 km). • Humic-type gas is from the source rock of the 3rd member of Shahejie Formation. • Sapropelic-type gas is from the source rock of the 4th member of Shahejie Formation. • Biodegraded gas: 13C-rich propane, depletion of propane and n-butane. • Secondary microbial gas: 13C-rich carbon dioxide and 13C-depleted methane. • Natural gas mainly accumulates near the source rock. [ABSTRACT FROM AUTHOR]