In the present investigation, Bhavnagar lignites of the Saurashtra basin （Gujarat） have been studied to assess their hydrocarbon generating potential. The samples of upper as well as lower lignite seams have been st...In the present investigation, Bhavnagar lignites of the Saurashtra basin （Gujarat） have been studied to assess their hydrocarbon generating potential. The samples of upper as well as lower lignite seams have been studied through microscopy and subjected to various chemical analyses viz. proximate analysis, ultimate analysis and Rock-Eval Pyrolysis. These lignites have high moisture and low to moderate ash yield but are characterized by high volatile matter. Petro- graphically they comprise predominantly of huminite group maceral while liptinite and inertinite groups occur in sub- ordinated amount. Huminite is chiefly composed of detrohuminite and telohuminite. The Tma~ （av. 416.23 ~C） and huminite reflectivity （0.28%-0.30%） indicate a low degree of maturity for these lignites which is also substantiated by the T,n~~ versus hydrogen index plot. The organic matter is subjugated by kerogen Type-III with a potential to expel hydrocarbon on liquefaction. Study further reveals that the fixed hydrocarbon is several folds higher than the free hydrocarbons. Being high in reactive maceral content, a high ＇conversion＇ and good ＇oil yield＇ values for these lignites were observed. Thus, the empirically derived values match well with those obtained through the experimental values of Rock-Eval Pyrolysis and validate their hydrocarbon generating potential.展开更多
Uncertainty quantification(UQ)to detect samples with large expected errors(outliers)is applied to reactive molecular potential energy surfaces(PESs).Three methods–Ensembles,deep evidential regression(DER),and Gaussia...Uncertainty quantification(UQ)to detect samples with large expected errors(outliers)is applied to reactive molecular potential energy surfaces(PESs).Three methods–Ensembles,deep evidential regression(DER),and Gaussian Mixture Models(GMM)—were applied to the H-transfer reaction between syn-Criegee and vinyl hydroxyperoxide.The results indicate that ensemble models provide the best results for detecting outliers,followed by GMM.For example,from a pool of 1000 structures with the largest uncertainty,the detection quality for outliers is~90%and~50%,respectively,if 25 or 1000 structures with large errors are sought.On the contrary,the limitations of the statistical assumptions of DER greatly impact its prediction capabilities.Finally,a structure-based indicator was found to be correlated with large average error,which may help to rapidly classify new structures into those that provide an advantage for refining the neural network.展开更多
OBJECTIVE： To provide in vitro evidence of Psorinum treatment against cancer cells in a controlled study. METHODS： Effects of homeopathic Psorinum 6× on cell viability were initially determined in several cance...OBJECTIVE： To provide in vitro evidence of Psorinum treatment against cancer cells in a controlled study. METHODS： Effects of homeopathic Psorinum 6× on cell viability were initially determined in several cancer cell lines, including A549, Hep G2 and MCF-7, using 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay, and an ethanol 6× control. The cell line that exhibited highest inhibition was selected and used in the following experiments. A range of Psorinum 6× doses was used to explore treatment effects on cell cycle arrest, cell death（apoptosis）, generation of reactive oxygen species（ROS） and change in mitochondrial membrane potential（MMP） using fl ow cytometry and fl uorescence microscopy, respectively. Expression of several signal proteins related to apoptosis and cell survival were quantified with Western blotting and confocal microscopy. Further, circular dichroism（CD） spectroscopy was used to determine possible drug-DNA interactions, as well as the induction of conformational changes. RESULTS： Treatment of cancer cell lines with Psorinum showed greater anticancer effects in A549 cells than in others. In A549 cells Psorinum treatment inhibited cell proliferation at 24 h after treatment, and arrested cell cycle at sub-G1 stage. It also induced ROS generation, MMP depolarization, morphological changes and DNA damage, as well as externalization of phosphatidyl serine. Further, increases in p53 expression, Bax expression, cytochrome c release, along with reduction of Bcl-2 level and caspase-3 activation were observed after Psorinum 6× treatment, which eventually drove A549 cells towards the mitochondria-mediated caspase-3-dependent pathway. CD spectroscopy revealed direct interaction of Psorinum with DNA, using calf thymus-DNA as target.CONCLUSION： Psorinum 6× triggered apoptosis in A549 cells via both up- and down-regulations of relevant signal proteins, including p53, caspase-3, Bax and Bcl-2.展开更多
AIM： To investigate the potential of pigment epitheliumderived factor（PEDF） to protect the immortalized rat retinal ganglion cells-5（RGC-5） exposed to Co Cl2-induced chemical hypoxia. METHODS： After being differ...AIM： To investigate the potential of pigment epitheliumderived factor（PEDF） to protect the immortalized rat retinal ganglion cells-5（RGC-5） exposed to Co Cl2-induced chemical hypoxia. METHODS： After being differentiated with staurosporine（SS）, RGC-5 cells were cultured in four conditions： control group cells cultured in Dulbecco ＇s modified eagle medium（DMEM） supplemented with 10% fetal bovine serum, 100 μmol/m L streptomycin and penicillin（named as normal conditions）; hypoxia group cells cultured in DMEM containing 300 μmol/m L Co Cl2; cells in the group protected by PEDF were first pretreated with 100 ng/m L PEDF for 2h and then cultured in the same condition as hypoxia group cells; and PEDF group cells that were cultured in the presence of 100 ng/m L PEDF under normal conditions. The cell viability was assessed by MTT assay, the percentage of apoptotic cells was quantified using Annexin V-FITC apoptosis kit, and intra-cellar reactive oxygen species（ROS） was measured by dichloro-dihydro-fluorescein diacetate（DCFH-DA） probe. The mitochondria-mediated apoptosis was also examined to further study the underlying mechanism of the protective effect of PEDF. The opening of mitochondrial permeability transition pores（m PTPs） and membrane potential（Δψm） were tested as cellular adenosine triphosphate（ATP） level and glutathione（GSH）. Also, the expression and distribution of Cyt C and apoptosis inducing factor（AIF） were observed.RESULTS： SS induced differentiation of RGC-5 cells resulting in elongation of their neurites and establishing contacts between outgrowths. Exposure to 300 μmol/m L Co Cl2 triggered death of 30% of the total cells in cultures within 24 h. At the same time, pretreatment with 100 ng/m L PEDF significantly suppressed the cell death induced by hypoxia（P〈0.05）. The apoptosis induced by treatment of Co Cl2 was that induced cell death accompanied with increasing intracellar ROS and decreasing GSH and ATP level. PEDF pretreatment suppressed these effects（P〈0.05）. Additionally, PEDF treatment inhibited the opening of m PTPs and suppressed decreasing of Δψm in RGC-5 cells, resulting in blocking of the mitochondrial apoptotic pathway.CONCLUSION： Pretreatment of RGC-5 cells with 100 ng/m L PEDF significantly decreases the extent of apoptosis. PEDF inhibits the opening of m PTPs and suppresses decreasing of Δψm. Moreover, PEDF also reduces ROS production and inhibits cellular ATP level＇s reduction. Cyt C and AIF activation in PEDF-pretreated cultures are also reduced. These results demonstrate the potential for PEDF to protect RGCs against hypoxic damage in vitro by preventing mitochondrial dysfunction.展开更多
The structures of self-assembled monolayers(SAMs)of short(methyl)and long(hexyl)chain alkyl thiols on the clean gold(111)surface were modeled using for the Au–S interactions either the reactive ReaxFF potential or th...The structures of self-assembled monolayers(SAMs)of short(methyl)and long(hexyl)chain alkyl thiols on the clean gold(111)surface were modeled using for the Au–S interactions either the reactive ReaxFF potential or the well-known nonreactive Morse potential,while for the Au–Au interactions either the ReaxFF potential or an embeddedatom method(EAM).Analysis of the molecular dynamics(MD)trajectories of possible SAM structures suggests that disordering of interfacial Au atoms is definitely driven by the gold–sulphur interactions.Our MD results reveal a novel structure where two methanethiol molecules are bound to a gold adatom that has been lifted from the surface at 300 K,and the same kind of RS–Au–SR motif was also observed for hexanethiol at 600 K but not at 300 K.What is more,the above motif is only observed for the reactive ReaxFF potential.Moreover,these results are in clear agreement with recent experiments and more costly first principles-based MD simulations.These findings strongly support the use of reactive potentials such as ReaxFF for gathering an accurate description of Au–S interactions in inexpensive classical MD simulations.展开更多
This study numerically investigates the thermo-poromechanical effects in a Canadian geothermal reservoir caused by long-term fluid production and injection.Using finite element modeling,it explores pore pressure diffu...This study numerically investigates the thermo-poromechanical effects in a Canadian geothermal reservoir caused by long-term fluid production and injection.Using finite element modeling,it explores pore pressure diffusion and thermal dynamics,incorporating both the geological structure of the rock mass and faults.The simulations utilize the IAPWS(International Association for the Properties of Water and Steam)equations to model fluid density and viscosity,ensuring realistic representations of heterogeneous pressure fields.The system replicates a doublet configuration within a faulted zone,featuring two hydraulically stimulated fractures.The primary aim is to assess the likelihood of fault reactivation under varying in-situ stress conditions over a 100-year geothermal operation.Results show that stress distribution is largely influenced by thermal stresses along the fluid circulation pathway,with fluid velocity and temperature gradients affecting reservoir stability.Minimal pore pressure changes highlight the dominant role of thermal stresses in controlling fault behavior.The analysis indicates no potential for fault reactivation,as slip tendency values remain below the critical threshold,even when accounting for reduced mechanical properties using the Hoek-Brown criterion.Thermal effects continue to influence the surrounding rock throughout the operational period,suggesting that the reservoir maintains mechanical stability conducive to sustained geothermal production and injection.These findings provide valuable insights into the long-term safety and behavior of geothermal reservoirs,offering important implications for future geothermal energy development and management strategies.展开更多
文摘In the present investigation, Bhavnagar lignites of the Saurashtra basin （Gujarat） have been studied to assess their hydrocarbon generating potential. The samples of upper as well as lower lignite seams have been studied through microscopy and subjected to various chemical analyses viz. proximate analysis, ultimate analysis and Rock-Eval Pyrolysis. These lignites have high moisture and low to moderate ash yield but are characterized by high volatile matter. Petro- graphically they comprise predominantly of huminite group maceral while liptinite and inertinite groups occur in sub- ordinated amount. Huminite is chiefly composed of detrohuminite and telohuminite. The Tma~ （av. 416.23 ~C） and huminite reflectivity （0.28%-0.30%） indicate a low degree of maturity for these lignites which is also substantiated by the T,n~~ versus hydrogen index plot. The organic matter is subjugated by kerogen Type-III with a potential to expel hydrocarbon on liquefaction. Study further reveals that the fixed hydrocarbon is several folds higher than the free hydrocarbons. Being high in reactive maceral content, a high ＇conversion＇ and good ＇oil yield＇ values for these lignites were observed. Thus, the empirically derived values match well with those obtained through the experimental values of Rock-Eval Pyrolysis and validate their hydrocarbon generating potential.
基金supported by the Swiss National Science Foundation through grants 200020_219779 and 200021_215088the University of Basel.L.I.V.S.acknowledges funding from the Swiss National Science Foundation(Grant P500PN_222297)to develop the last stages of this work.
文摘Uncertainty quantification(UQ)to detect samples with large expected errors(outliers)is applied to reactive molecular potential energy surfaces(PESs).Three methods–Ensembles,deep evidential regression(DER),and Gaussian Mixture Models(GMM)—were applied to the H-transfer reaction between syn-Criegee and vinyl hydroxyperoxide.The results indicate that ensemble models provide the best results for detecting outliers,followed by GMM.For example,from a pool of 1000 structures with the largest uncertainty,the detection quality for outliers is~90%and~50%,respectively,if 25 or 1000 structures with large errors are sought.On the contrary,the limitations of the statistical assumptions of DER greatly impact its prediction capabilities.Finally,a structure-based indicator was found to be correlated with large average error,which may help to rapidly classify new structures into those that provide an advantage for refining the neural network.
文摘OBJECTIVE： To provide in vitro evidence of Psorinum treatment against cancer cells in a controlled study. METHODS： Effects of homeopathic Psorinum 6× on cell viability were initially determined in several cancer cell lines, including A549, Hep G2 and MCF-7, using 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay, and an ethanol 6× control. The cell line that exhibited highest inhibition was selected and used in the following experiments. A range of Psorinum 6× doses was used to explore treatment effects on cell cycle arrest, cell death（apoptosis）, generation of reactive oxygen species（ROS） and change in mitochondrial membrane potential（MMP） using fl ow cytometry and fl uorescence microscopy, respectively. Expression of several signal proteins related to apoptosis and cell survival were quantified with Western blotting and confocal microscopy. Further, circular dichroism（CD） spectroscopy was used to determine possible drug-DNA interactions, as well as the induction of conformational changes. RESULTS： Treatment of cancer cell lines with Psorinum showed greater anticancer effects in A549 cells than in others. In A549 cells Psorinum treatment inhibited cell proliferation at 24 h after treatment, and arrested cell cycle at sub-G1 stage. It also induced ROS generation, MMP depolarization, morphological changes and DNA damage, as well as externalization of phosphatidyl serine. Further, increases in p53 expression, Bax expression, cytochrome c release, along with reduction of Bcl-2 level and caspase-3 activation were observed after Psorinum 6× treatment, which eventually drove A549 cells towards the mitochondria-mediated caspase-3-dependent pathway. CD spectroscopy revealed direct interaction of Psorinum with DNA, using calf thymus-DNA as target.CONCLUSION： Psorinum 6× triggered apoptosis in A549 cells via both up- and down-regulations of relevant signal proteins, including p53, caspase-3, Bax and Bcl-2.
基金Supported by National Natural Science Foundation of China(No.81100665)
文摘AIM： To investigate the potential of pigment epitheliumderived factor（PEDF） to protect the immortalized rat retinal ganglion cells-5（RGC-5） exposed to Co Cl2-induced chemical hypoxia. METHODS： After being differentiated with staurosporine（SS）, RGC-5 cells were cultured in four conditions： control group cells cultured in Dulbecco ＇s modified eagle medium（DMEM） supplemented with 10% fetal bovine serum, 100 μmol/m L streptomycin and penicillin（named as normal conditions）; hypoxia group cells cultured in DMEM containing 300 μmol/m L Co Cl2; cells in the group protected by PEDF were first pretreated with 100 ng/m L PEDF for 2h and then cultured in the same condition as hypoxia group cells; and PEDF group cells that were cultured in the presence of 100 ng/m L PEDF under normal conditions. The cell viability was assessed by MTT assay, the percentage of apoptotic cells was quantified using Annexin V-FITC apoptosis kit, and intra-cellar reactive oxygen species（ROS） was measured by dichloro-dihydro-fluorescein diacetate（DCFH-DA） probe. The mitochondria-mediated apoptosis was also examined to further study the underlying mechanism of the protective effect of PEDF. The opening of mitochondrial permeability transition pores（m PTPs） and membrane potential（Δψm） were tested as cellular adenosine triphosphate（ATP） level and glutathione（GSH）. Also, the expression and distribution of Cyt C and apoptosis inducing factor（AIF） were observed.RESULTS： SS induced differentiation of RGC-5 cells resulting in elongation of their neurites and establishing contacts between outgrowths. Exposure to 300 μmol/m L Co Cl2 triggered death of 30% of the total cells in cultures within 24 h. At the same time, pretreatment with 100 ng/m L PEDF significantly suppressed the cell death induced by hypoxia（P〈0.05）. The apoptosis induced by treatment of Co Cl2 was that induced cell death accompanied with increasing intracellar ROS and decreasing GSH and ATP level. PEDF pretreatment suppressed these effects（P〈0.05）. Additionally, PEDF treatment inhibited the opening of m PTPs and suppressed decreasing of Δψm in RGC-5 cells, resulting in blocking of the mitochondrial apoptotic pathway.CONCLUSION： Pretreatment of RGC-5 cells with 100 ng/m L PEDF significantly decreases the extent of apoptosis. PEDF inhibits the opening of m PTPs and suppresses decreasing of Δψm. Moreover, PEDF also reduces ROS production and inhibits cellular ATP level＇s reduction. Cyt C and AIF activation in PEDF-pretreated cultures are also reduced. These results demonstrate the potential for PEDF to protect RGCs against hypoxic damage in vitro by preventing mitochondrial dysfunction.
基金supported by Project PTDC/CTMNAN/112241/2009Grant No.Pest−C/EQB/LA0006/2011+2 种基金financed by FEDER through COMPETE-Programa Operacional Factores de CompetitividadeFCT-Funda¸cão para a Ciência e a Tecnologia.J.L.C.Fajin acknowledges FCT for the grant SFRH/BPD/64566/2009 cofinancedthe Fundo Social Europen(FSE).
文摘The structures of self-assembled monolayers(SAMs)of short(methyl)and long(hexyl)chain alkyl thiols on the clean gold(111)surface were modeled using for the Au–S interactions either the reactive ReaxFF potential or the well-known nonreactive Morse potential,while for the Au–Au interactions either the ReaxFF potential or an embeddedatom method(EAM).Analysis of the molecular dynamics(MD)trajectories of possible SAM structures suggests that disordering of interfacial Au atoms is definitely driven by the gold–sulphur interactions.Our MD results reveal a novel structure where two methanethiol molecules are bound to a gold adatom that has been lifted from the surface at 300 K,and the same kind of RS–Au–SR motif was also observed for hexanethiol at 600 K but not at 300 K.What is more,the above motif is only observed for the reactive ReaxFF potential.Moreover,these results are in clear agreement with recent experiments and more costly first principles-based MD simulations.These findings strongly support the use of reactive potentials such as ReaxFF for gathering an accurate description of Au–S interactions in inexpensive classical MD simulations.
基金the Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery Grant Canada(NO.RGPIN-2024-05104).
文摘This study numerically investigates the thermo-poromechanical effects in a Canadian geothermal reservoir caused by long-term fluid production and injection.Using finite element modeling,it explores pore pressure diffusion and thermal dynamics,incorporating both the geological structure of the rock mass and faults.The simulations utilize the IAPWS(International Association for the Properties of Water and Steam)equations to model fluid density and viscosity,ensuring realistic representations of heterogeneous pressure fields.The system replicates a doublet configuration within a faulted zone,featuring two hydraulically stimulated fractures.The primary aim is to assess the likelihood of fault reactivation under varying in-situ stress conditions over a 100-year geothermal operation.Results show that stress distribution is largely influenced by thermal stresses along the fluid circulation pathway,with fluid velocity and temperature gradients affecting reservoir stability.Minimal pore pressure changes highlight the dominant role of thermal stresses in controlling fault behavior.The analysis indicates no potential for fault reactivation,as slip tendency values remain below the critical threshold,even when accounting for reduced mechanical properties using the Hoek-Brown criterion.Thermal effects continue to influence the surrounding rock throughout the operational period,suggesting that the reservoir maintains mechanical stability conducive to sustained geothermal production and injection.These findings provide valuable insights into the long-term safety and behavior of geothermal reservoirs,offering important implications for future geothermal energy development and management strategies.
