A new three-dimensional laterolog array sonde（3D-LS） is presented. The 3DLS is based on existing high-resolution laterolog array and azimuthal resistivity imaging sondes with radial, longitudinal, and circumferentia...A new three-dimensional laterolog array sonde（3D-LS） is presented. The 3DLS is based on existing high-resolution laterolog array and azimuthal resistivity imaging sondes with radial, longitudinal, and circumferential detection abilities. Six investigation modes are designed using the 3D finite-element method and different investigation depths are simulated based on the pseudo-geometrical factor of the six modes. The invasion profile is described using multi-array radial logs. From the analysis of the pseudo-geometrical factor, the investigation depth of the 3D-LS is about 1.5 m for conductive invasion, which is close to that of the dual laterolog tool but greater than that of the highly integrated azimuthal laterolog sonde. The vertical and azimuthal resolution is also analyzed with the same method. The 3DLS can detect low-resistivity anomalies of 0.5 m thickness and 15？ around the borehole for infinitely thick formations. This study lays the foundation for more work on 3D laterolog array sonde for evaluating low-resistivity anomalies.展开更多
OBJECTIVE:To evaluates the antioxidant and hepatoprotective potentials of Dicoma anomala Sond.(Asteraceae) on body weight,feed and water intake,biochemical parameters and organ histology.METHODS:Various concentrations...OBJECTIVE:To evaluates the antioxidant and hepatoprotective potentials of Dicoma anomala Sond.(Asteraceae) on body weight,feed and water intake,biochemical parameters and organ histology.METHODS:Various concentrations(1.56-25 μg/m L)were used in the in vitro assays 1,1-diphenyl-2-picryl hydrazyl(DPPH,superoxide anion,hydroxyl radicals,etc.).The effects of treatment with 125,250 and 250 mg/m L Dicoma anomala aqueous roots extract(DARE) was investigated in vivo in the CCl4-induced hepatotoxic rats during the 15 days study.RESULTS:Water extract exhibited the best activity(IC50:15.20 ± 0.03,11.70 ± 0.10,and 0.84 ± 0.05 μg/m L) in vitro in DPPH,hydroxyl and superoxide anion radicals,respectively,when compared with standards.Pre-treatment and treatment with different concentrations of DARE significantly(P < 0.05)attenuated the elevated serum activities of aspartate transaminase,alanine transaminase levels while increasing the activities of superoxide dismutase,catalase and glutathione peroxidase.The histopathological evaluations revealed extensive liver damage characterized by severe vacuolar and cytoplasmic degeneration,hepatic necrosis,and cellular infilteration in pre-treated groups while in the treated groups;such liver damages were not observed most especially at 500 mg/kg dose.CONCLUSION:The results proved the hepatoprotective potential of DARE against CCl4-induced oxidative stress.Moreover,histopathological examinations revealed better therapeutic advantage of DARE than prophylactic use.展开更多
Conducting scientific drilling on subglacial lakes and obtaining samples of subglacial lake water holds great significance in unraveling the formation and evolution of Antarctic subglacial lakes and early Earth's ...Conducting scientific drilling on subglacial lakes and obtaining samples of subglacial lake water holds great significance in unraveling the formation and evolution of Antarctic subglacial lakes and early Earth's life forms.Despite various approaches to access and directly sample subglacial water and sediments,clean access and exploration of subglacial lakes remain challenging.To address this concern,Jilin University has developed the RECoverable Autonomous Sonde(RECAS)prototype.This technology enables sampling and in-situ detection of subglacial lake water while being isolated from the surface,thus minimizing the risk of pollution.Laboratory tests,including downward and upward drilling,long-running,remote-control,and cold-environment assessments,were conducted to validate the sonde's principle and functionality.During the 38th Chinese National Antarctic Research Expedition,CHINARE(2021–2022 season),the RECAS prototype underwent testing on the flank region of Dalk glacier,10 km from Zhongshan Station in Antarctica.Three boreholes with depths of 200.3,183.2,and 133.5 m were successfully drilled,with the refrozen meltwater sealing the boreholes during the process.Approximately 600 mL of melted water samples were collected from each hole.Throughout the drilling tests,all systems of the RECAS prototype performed within the expected ranges.展开更多
基金sponsored by the National Oil and Gas Major Projects(No.2011ZX05020-009)
文摘A new three-dimensional laterolog array sonde（3D-LS） is presented. The 3DLS is based on existing high-resolution laterolog array and azimuthal resistivity imaging sondes with radial, longitudinal, and circumferential detection abilities. Six investigation modes are designed using the 3D finite-element method and different investigation depths are simulated based on the pseudo-geometrical factor of the six modes. The invasion profile is described using multi-array radial logs. From the analysis of the pseudo-geometrical factor, the investigation depth of the 3D-LS is about 1.5 m for conductive invasion, which is close to that of the dual laterolog tool but greater than that of the highly integrated azimuthal laterolog sonde. The vertical and azimuthal resolution is also analyzed with the same method. The 3DLS can detect low-resistivity anomalies of 0.5 m thickness and 15？ around the borehole for infinitely thick formations. This study lays the foundation for more work on 3D laterolog array sonde for evaluating low-resistivity anomalies.
基金Supported by Research committee,University of the Free State,Qwaqwa campus,(entity No.211427604)Free State,SA
文摘OBJECTIVE:To evaluates the antioxidant and hepatoprotective potentials of Dicoma anomala Sond.(Asteraceae) on body weight,feed and water intake,biochemical parameters and organ histology.METHODS:Various concentrations(1.56-25 μg/m L)were used in the in vitro assays 1,1-diphenyl-2-picryl hydrazyl(DPPH,superoxide anion,hydroxyl radicals,etc.).The effects of treatment with 125,250 and 250 mg/m L Dicoma anomala aqueous roots extract(DARE) was investigated in vivo in the CCl4-induced hepatotoxic rats during the 15 days study.RESULTS:Water extract exhibited the best activity(IC50:15.20 ± 0.03,11.70 ± 0.10,and 0.84 ± 0.05 μg/m L) in vitro in DPPH,hydroxyl and superoxide anion radicals,respectively,when compared with standards.Pre-treatment and treatment with different concentrations of DARE significantly(P < 0.05)attenuated the elevated serum activities of aspartate transaminase,alanine transaminase levels while increasing the activities of superoxide dismutase,catalase and glutathione peroxidase.The histopathological evaluations revealed extensive liver damage characterized by severe vacuolar and cytoplasmic degeneration,hepatic necrosis,and cellular infilteration in pre-treated groups while in the treated groups;such liver damages were not observed most especially at 500 mg/kg dose.CONCLUSION:The results proved the hepatoprotective potential of DARE against CCl4-induced oxidative stress.Moreover,histopathological examinations revealed better therapeutic advantage of DARE than prophylactic use.
基金supported by the National Key Research and Development Project of the Ministry of Science and Technology of China(Grant Nos.2016YFC1400302,2023YFC2812602)the National Natural Science Foundation of China(Grant No.41941005)。
文摘Conducting scientific drilling on subglacial lakes and obtaining samples of subglacial lake water holds great significance in unraveling the formation and evolution of Antarctic subglacial lakes and early Earth's life forms.Despite various approaches to access and directly sample subglacial water and sediments,clean access and exploration of subglacial lakes remain challenging.To address this concern,Jilin University has developed the RECoverable Autonomous Sonde(RECAS)prototype.This technology enables sampling and in-situ detection of subglacial lake water while being isolated from the surface,thus minimizing the risk of pollution.Laboratory tests,including downward and upward drilling,long-running,remote-control,and cold-environment assessments,were conducted to validate the sonde's principle and functionality.During the 38th Chinese National Antarctic Research Expedition,CHINARE(2021–2022 season),the RECAS prototype underwent testing on the flank region of Dalk glacier,10 km from Zhongshan Station in Antarctica.Three boreholes with depths of 200.3,183.2,and 133.5 m were successfully drilled,with the refrozen meltwater sealing the boreholes during the process.Approximately 600 mL of melted water samples were collected from each hole.Throughout the drilling tests,all systems of the RECAS prototype performed within the expected ranges.
