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It is important to determine the chemical composition of gases trapped in rocks. The technique of using carrier gas and chemical analysis to release and collect gases is very time-consuming. There is little reported about Gas Chromatography analysis of rock degassing under high vacuum, and the total amount of gases are not commonly measured. It is difficult to analyze gases with similar molecular weights by Mass Spectrometer and because of these problems, a high vacuum rock sample degassing device has been developed. The vacuum of the device is < 10-4 Pa. The blank sample pressure is < 0.1 Pa, the accuracy for N2 in the air is 0.63%, and the minimum measurable quantity is < 1 mm3 at standard temperature and pressure. The high vacuum device is coupled with a Gas Chromatography with a pulsed discharge detector, which gives a high sensitive gas chromatographic analysis of the chemical composition of gases in rocks. The gas released from Wudalianchi volcanic rocks in the Songliao Basin reservoirs and shale samples from the Sichuan basin have been analyzed using this system. The results show that the total amount of gas released from the rock can be directly measured. Less sample weight is needed during stage heating, and gas composition analysis is more sensitive compared with the previous experimental device and method. The analyzed main component targeted is the common component in gas-released rock.

U(1)X SSM is the extension of the minimal supersymmetric standard model (MSSM) and its local gauge group is SU(3)C× SU(2)L× U(1)Y× U(1)X. To obtain this model, three singlet new Higgs superfields and right-handed neutrinos are added to MSSM. In the framework of U(1)XSSM, we study the Higgs mass and take the lightest CP-even sneutrino as a cold dark matter candidate. For the lightest CP-even sneutrino, the relic density and the cross section for dark matter scattering off nucleon are both researched. In suitable parameter space of the model, the numerical results satisfy the constraints of the relic density and the cross section with the nucleon. [ABSTRACT FROM AUTHOR]

The three types of low mature organic-rich samples from US Green River shale (Type I kerogen), Woodford shale (Type II kerogen), and China Pearl River Mouth Basin( Type III kerogen) were chosen as the initial samples for pyrolysis simulation on hydrocarbon generation. A pyrolysis system of sealed gold tubes in high pressure vessels was employed to conduct pyrolysis experiments at two heating rates of 20 °C/h and 2 °C/h under a constant confining pressure of 24. 1 MPa. The yields of gaseous hydrocarbons (C1-5) and liquid hydrocarbons (C6-14 and C14+), and the carbon isotopic compositions of gaseous hydrocarbons (C1-C4) were measured to reveal the generation mechanism of shale gas. The results show that the organic matter conversion from organic-rich shales to oil and gas can be divided into three stages: oil generation, gas generation from oil secondary cracking and gaseous hydrocarbons cracking. At the stage of oil generation by the thermal decomposition of primary kerogen, the yields of liquid hydrocarbons increase rapidly with the increase of temperature, and reach the peak values at approximately 0. 9%- 1.1% Ro, whereas gaseous hydrocarbons show low yields. At the stage of oil secondary cracking, gaseous hydrocarbons increase rapidly in the yields associated with the decreases in the yield of liquid hydrocarbons. At the stage of gaseous hydrocarbons cracking, the gas yields increase slightly, whereas gas is getting drier and enriches in CH4. The carbon isotopes of gaseous hydrocarbons vary from heavier to lighter with the increase of temperature, and reach the lightest values before the end of oil cracking, and then become heavier. The partial reversals of carbon isotopic compositions of gaseous hydrocarbons at the stage of oil cracking is observed for Type I shale, i. e., δ13C1<δ13C2<δ13nC4. The results also suggest that shale gas is mainly derived from kerogen primary cracking and oil and gas secondary cracking, and shale gas content is constrained by the organic matter type and thermal maturity, and the Type I shale has the highest gas yield. The partial reversal distributions of carbon isotopic compositions of gaseous hydrocarbons in shale gas could be caused by oil secondary cracking, or the mixing of gaseous hydrocarbons from different stages of thermal maturation. [ABSTRACT FROM AUTHOR]

The reaction of N-diphenylphosphinoyl imines 1 with [3-(trimethylsilyl)allyl]dimethylsulfonium bromide (5) in the presence of Nail at room temperature predominantly gave trans-vinylaziridines 4. On the other hand, cis-vinylaziridines 4 were the main products when the preformed ylide prepared from the reaction of [3-(trimethylsilyl)allyl]diphenylsulfonium perchlorate (6) was reacted with the same imines 1 at low temperature, trans-Aziridines were also obtained when imines 1 and sulfinimines 9 were reacted with N,N-dimethylacetamide-2-dimethylsulfonium bromide (7) in the presence of a base, respectively. A mechanistic study showed that the stereochemistry of these reactions was controlled by the reactivity of the imines and ylides. A higher reactivity of imines and ylides favors the formation of cis-aziridines, whereas a lower reactivity leads to trans-products. [ABSTRACT FROM AUTHOR]

Background and Aim: Obesity is association with elevated risks of erosive esophagitis (EE), and metabolic abnormalities play crucial roles in its development. The aim of the study was to assess the association between metabolic obesity phenotypes and the risk of EE., Methods: This retrospective study enrolled 11,599 subjects who had undergone upper gastrointestinal endoscopy at the First Affiliated Hospital of Dalian Medical University from January 1, 2008, to December 31, 2023. The enrolled individuals were grouped into four cohorts based on their metabolic health and obesity profiles, namely, metabolically healthy non-obesity (MHNO; n=2134, 18.4%), metabolically healthy obesity (MHO; n=1736, 15.0%), metabolically unhealthy non-obesity (MUNO; n=4290, 37.0%), and metabolically unhealthy obesity (MUO; n=3439, 29.6%). The relationships of the different phenotypes of metabolic obesity with the risks of developing EE in the different sexes and age groups were investigated by multivariate logistic regression analysis., Results: The MUNO, MHO, and MUO cohorts exhibited elevated risks of developing EE than the MHNO cohort. The confounding factors were adjusted for, and the findings revealed that the MUO cohort exhibited the greatest risk of EE, with odds ratios (ORs) of 5.473 (95% CI: 4.181-7.165) and 7.566 (95% CI: 5.718-10.010) for males and females, respectively. The frequency of occurrence of EE increased following an increase in proportion of metabolic risk factors. Subgroup analyses showed that the individuals under and over 60 years of age in the MHO, MUNO, and MUO cohorts exhibited elevated risks of developing EE. Further analysis suggested that obesity has a stronger influence on the risks of developing EE compared to metabolic disorders., Conclusion: Metabolic disorders and obesity are both related with an elevated risk of EE, in which obesity has a potentially stronger influence. Clinical interventions should target both obesity and metabolic disorders to reduce EE risk., Competing Interests: The authors declare that they have no competing interests in this work., (© 2024 He et al.)

Increasing epidemiological studies have focused on the associations between interleukin-6 (IL-6) gene -174G>C polymorphism and atherosclerotic diseases, but the results are still controversial. This meta-analysis was designed to identify whether this association exists. PubMed, Embase, Web of Science, Cochrane database, Clinicaltrials.gov and Current Controlled Trials, Chinese Clinical Trial Registry, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. The crude odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the IL-6 gene -174G>C polymorphism and atherosclerosis ( AS ) risk. The subgroup analyses were made on the following: ethnicity, atherosclerotic diseases and source of controls. Finally, 50 studies (15,029 cases and 18,485 controls) were included in this meta-analysis. Overall, no significant association was found between the IL-6 gene -174G>C polymorphism and AS risk (for C allele vs. G allele: OR=1.02, 95% CI=0.94-1.11, p=0.64; for C/C vs. G/G: OR=1.01, 95% CI=0.85-1.21, p=0.88; for C/C vs. C/G+G/G: OR=0.97, 95% CI=0.84-1.12, p=0.68; for C/C+C/G vs. G/G: OR=1.07, 95% CI=0.97-1.17, p=0.18). In the subgroup analyses, significant associations were found between the IL-6 gene -174G>C polymorphism and AS in non-Caucasian group (for CC+CG vs. GG: OR=1.22, 95% CI=1.06-1.41, p=0.005), other atherosclerotic diseases group (for C allele vs. G allele: OR =0.75, 95% CI=0.61-0.93, p=0.008; for C/C vs. G/G: OR=0.56, 95% CI=0.38-0.81, p=0.002; for C/C vs. C/G+G/G: OR=0.60, 95% CI=0.45-0.79, p=0.0004) and population-based group (for C allele vs. G allele: OR=1.09, 95% CI=1.00-1.18, p=0.04; for CC+CG vs. GG: OR=1.15, 95% CI=1.04-1.27, p=0.005). In summary, the present meta-analysis suggests that the IL-6 gene -174G C polymorphism is associated with the susceptibility to AS. However, due to the high heterogeneity in the meta-analysis, the results should be interpreted with caution., (© 2013 Elsevier B.V. All rights reserved.)