Polyhydroxyalkanoates(PHA)have been produced by some bacteria as bioplastics for many years.Yet their commercialization is still on the way.A few issues are related to the difficulty of PHA commercialization:namely,hi...Polyhydroxyalkanoates(PHA)have been produced by some bacteria as bioplastics for many years.Yet their commercialization is still on the way.A few issues are related to the difficulty of PHA commercialization:namely,high cost and instabilities on molecular weights(Mw)and structures,thus instability on thermo-mechanical properties.The high cost is the result of complicated bioprocessing associated with sterilization,low conversion of carbon substrates to PHA products,and slow growth of microorganisms as well as difficulty of downstream separation.Future engineering on PHA producing microorganisms should be focused on contamination resistant bacteria especially extremophiles,developments of engineering approaches for the extremophiles,increase on carbon substrates to PHA conversion and controlling Mw of PHA.The concept proof studies could still be conducted on E.coli or Pseudomonas spp.that are easily used for molecular manipulations.In this review,we will use E.coli and halophiles as examples to show how to engineer bacteria for enhanced PHA biosynthesis and for increasing PHA competitiveness.展开更多
On September 15,2014,China National Offshore Oil Co.,Ltd announced that a high production of oil and gas flow of 1.6106 m3/d was obtained in Well LS17-2-1 in deepwater area in northern South China Sea,which is the fi...On September 15,2014,China National Offshore Oil Co.,Ltd announced that a high production of oil and gas flow of 1.6106 m3/d was obtained in Well LS17-2-1 in deepwater area in northern South China Sea,which is the first great oil and gas discovery for self-run deepwater exploration in China sea areas,and a strategic breakthrough was made in natural gas exploration in deepwater area of Lingshui sag in Qiongdongnan Basin.Under the combined action of climax of international deepwater exploration,high oil prices,national demands of China,practical needs of exploration,breakthroughs in seismic exploration and testing technologies,innovations in geological cognition and breakthroughs in deepwater operation equipment,Lingshui 17-2 gas field is discovered.Among these factors,the innovation in reservoir forming geological cognition directly promotes the discovery.The quality of seismic data in the early time is poor,so key reservoir forming conditions such as effective source rocks,high quality reservoirs and oil-gas migration pathways are unable to be ascertained;with support of new seismic acquisition and processing technology,some researches show that Lingshui sag is a successive large and deep sag with an area of 5000 km2 and the maximum thickness of Cenozoic stratum of 13 km.In the Early Oligocene,the Lingshui sag was a semi-closed delta-estuarine environment,where the coalmeasure and marine mudstones in Lower Oligocene Yacheng Formation were developed.The Lingshui sag is a sag with high temperature,and the bottom temperature of source rocks in Yacheng Formation can exceed 250C,but the simulation experiment of hydrocarbon generation at high temperature indicates that the main part of this set of source rock is still in the gas-generation window,with resources of nearly 1 trillion cubic meters,so the Lingshui sag is a hydrocarbon-rich generation sag.In the Neogene,the axial canyon channel from the Thu Bon River in Vietnam passed through the Lingshui sag,and five stages of secondary channels were developed in the axi展开更多
The carbon and hydrogen isotopic composition of biogenic gas is of great importance for the study of its generation pathway and reservoiring characteristics. In this paper, the formation pathways and reservoiring char...The carbon and hydrogen isotopic composition of biogenic gas is of great importance for the study of its generation pathway and reservoiring characteristics. In this paper, the formation pathways and reservoiring characteristics of biogenic gas reservoirs in China are described in terms of the carbon and hydrogen isotopic compositions of 31 gas samples from 10 biogenic gas reservoirs. The study shows that the hydrogen isotopic compositions of these biogenic gas reservoirs can be divided into three intervals: δDCH4>-200‰,-250‰<δDCH4<-200‰ and δDCH4<-250‰. The forerunners believed that the main generation pathway of biogenic gas under the condition of continental fresh water is acetic fermentation. Our research results showed that the generation pathway of biogenic gas under the condition of marine facies is typical CO2-reduction, the biogenic gas has heavy hydrogen isotopic composition: its δDCH4 values are higher than-200‰; that the biogenic gas under the condition of continental facies also was generated by the same way, but its hydrogen isotopic composition is lighter than that of biogenetic gas generated under typical marine facies condition: -250‰<δDCH4<-200‰, the δDCH4 values may be related to the salinity of the water medium in ancient lakes. From the relevant data of the Qaidam Basin, it can be seen that the hydrogen isotopic composition of biogenic methane has the same variation trend with increasing salinity of water medium. There are biogenic gas reservoirs formed in transitional regions under the condition of continental facies. These gas reservoirs resulted from both CO2-reduction and acetic fermentation, the formation of which may be related to the non-variant salinity of ancient water medium and the relatively high geothermal gradient, as is the case encountered in the Baoshan Basin. The biogenic gas generating in these regions has light hydrogen isotopic composition: δDCH4<-250‰, and relatively heavy carbon isotopic composition. There is a fairly strong negative correlation b展开更多
Objective:Hereditary colorectal cancer(CRC)accounts for approximately 5%–10%of all CRC cases.The full profile of CRC-related germline mutations and the corresponding somatic mutational profile have not been fully det...Objective:Hereditary colorectal cancer(CRC)accounts for approximately 5%–10%of all CRC cases.The full profile of CRC-related germline mutations and the corresponding somatic mutational profile have not been fully determined in the Chinese population.Methods:We performed the first population study investigating the germline mutation status in more than 1,000(n=1,923)Chinese patients with CRC and examined their relationship with the somatic mutational landscape.Germline alterations were examined with a 58-gene next-generation sequencing panel,and somatic alterations were examined with a 605-gene panel.Results:A total of 92 pathogenic(P)mutations were identified in 85 patients,and 81 likely pathogenic(LP)germline mutations were identified in 62 patients,accounting for 7.6%(147/1,923)of all patients.MSH2 and APC was the most mutated gene in the Lynch syndrome and non-Lynch syndrome groups,respectively.Patients with P/LP mutations had a significantly higher ratio of microsatellite instability,highly deficient mismatch repair,family history of CRC,and lower age.The somatic mutational landscape revealed a significantly higher mutational frequency in the P group and a trend toward higher copy number variations in the non-P group.The Lynch syndrome group had a significantly higher mutational frequency and tumor mutational burden than the nonLynch syndrome group.Clustering analysis revealed that the Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Population risk analysis indicated that the overall odds ratio was 11.13(95%CI:8.289–15.44)for the P group and 20.68(95%CI:12.89–33.18)for the LP group.Conclusions:Distinct features were revealed in Chinese patients with CRC with germline mutations.The Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Patients with P/LP germline muta展开更多
Migration and accumulation simulation of oil and gas in carrier systems has always been a difficult subject in the quantitative study of petroleum geology. In view of the fact that the traditional geological modeling ...Migration and accumulation simulation of oil and gas in carrier systems has always been a difficult subject in the quantitative study of petroleum geology. In view of the fact that the traditional geological modeling technology can not establish the interrelation of carriers in three dimensional space, we have proposed a hybrid-dimensional mesh modeling technology consisting of body(stratum), surfaces(faults and unconformities), lines and points, which provides an important research method for the description of geometry of sand bodies, faults and unconformities, the 3 D geological modeling of complex tectonic areas, and the simulation of hydrocarbon migration and accumulation. Furthermore, we have advanced a 3 D hydrocarbon migration pathway tracking method based on the hybrid-dimensional mesh of the carrier system. The application of this technology in western Luliang Uplift of Junggar Basin shows that the technology can effectively characterize the transport effect of fault planes, unconformities and sand bodies, indicate the hydrocarbon migration pathways, simulate the process of oil accumulation, reservoir adjustment and secondary reservoir formation, predict the hydrocarbon distribution. It is found through the simulation that the areas around the paleo-oil reservoir and covered by migration pathways are favorable sites for oil and gas distribution.展开更多
The current idea behind brain pathology is that disease is initiated by mild disturbances of common physiological processes. Overtime, the disruption of the neuronal homeostasis will determine irreversible degeneratio...The current idea behind brain pathology is that disease is initiated by mild disturbances of common physiological processes. Overtime, the disruption of the neuronal homeostasis will determine irreversible degeneration and neuronal apoptosis. This could be also true in the case of nerve growth factor （NGF） al- terations in sporadic Alzheimer＇s disease （AD）, an age-related pathology characterized by cholinergic loss, amyloid plaques and neurofibrillary tangles. In fact, the pathway activated by NGF, a key neurotrophin for the metabolism of basal forebrain cholinergic neurons （BFCN）, is one of the first homeostatic systems affected in prodromal AD. NGF signaling dysfunctions have been thought for decades to occur in AD late stages, as a mere consequence of amyloid-driven disruption of the retrograde axonal transport of neuro- trophins to BFCN. Nowadays, a wealth of knowledge is potentially opening a new scenario： NGF signaling impairment occurs at the onset of AD and correlates better than amyloid load with cognitive decline. The recent acceleration in the characterization of anatomical, functional and molecular profiles of early AD is aimed at maximizing the efficacy of existing treatments and setting novel therapies. Accordingly, the elucidation of the molecular events underlying APP metabolism regulation by the NGF pathway in the sep- to-hippocampal system is crucial for the identification of new target molecules to slow and eventually halt mild cognitive impairment （MCI） and its progression toward AD.展开更多
基金This research was financially supported by a grant from Ministry of Sciences and Technology(Grant No.2016YFB0302504)grants from National Natural Science Foundation of China(Grant No.31430003)Tsinghua President Fund also supported this project(Grant No.2015THZ10).
文摘Polyhydroxyalkanoates(PHA)have been produced by some bacteria as bioplastics for many years.Yet their commercialization is still on the way.A few issues are related to the difficulty of PHA commercialization:namely,high cost and instabilities on molecular weights(Mw)and structures,thus instability on thermo-mechanical properties.The high cost is the result of complicated bioprocessing associated with sterilization,low conversion of carbon substrates to PHA products,and slow growth of microorganisms as well as difficulty of downstream separation.Future engineering on PHA producing microorganisms should be focused on contamination resistant bacteria especially extremophiles,developments of engineering approaches for the extremophiles,increase on carbon substrates to PHA conversion and controlling Mw of PHA.The concept proof studies could still be conducted on E.coli or Pseudomonas spp.that are easily used for molecular manipulations.In this review,we will use E.coli and halophiles as examples to show how to engineer bacteria for enhanced PHA biosynthesis and for increasing PHA competitiveness.
基金The work was supported by China National Significant Science and Technology Project(No.2008ZX05025,No.2011ZX05025,No.2016ZX05026)China National Key Basic Research and Development Program(973 Program)(2009CB219400)Project of Ministry of Land and Resources of the People's Republic of China(XQ2004-05,XQ2007-05).
文摘On September 15,2014,China National Offshore Oil Co.,Ltd announced that a high production of oil and gas flow of 1.6106 m3/d was obtained in Well LS17-2-1 in deepwater area in northern South China Sea,which is the first great oil and gas discovery for self-run deepwater exploration in China sea areas,and a strategic breakthrough was made in natural gas exploration in deepwater area of Lingshui sag in Qiongdongnan Basin.Under the combined action of climax of international deepwater exploration,high oil prices,national demands of China,practical needs of exploration,breakthroughs in seismic exploration and testing technologies,innovations in geological cognition and breakthroughs in deepwater operation equipment,Lingshui 17-2 gas field is discovered.Among these factors,the innovation in reservoir forming geological cognition directly promotes the discovery.The quality of seismic data in the early time is poor,so key reservoir forming conditions such as effective source rocks,high quality reservoirs and oil-gas migration pathways are unable to be ascertained;with support of new seismic acquisition and processing technology,some researches show that Lingshui sag is a successive large and deep sag with an area of 5000 km2 and the maximum thickness of Cenozoic stratum of 13 km.In the Early Oligocene,the Lingshui sag was a semi-closed delta-estuarine environment,where the coalmeasure and marine mudstones in Lower Oligocene Yacheng Formation were developed.The Lingshui sag is a sag with high temperature,and the bottom temperature of source rocks in Yacheng Formation can exceed 250C,but the simulation experiment of hydrocarbon generation at high temperature indicates that the main part of this set of source rock is still in the gas-generation window,with resources of nearly 1 trillion cubic meters,so the Lingshui sag is a hydrocarbon-rich generation sag.In the Neogene,the axial canyon channel from the Thu Bon River in Vietnam passed through the Lingshui sag,and five stages of secondary channels were developed in the axi
基金supported by the National Natural Science Foundation of China (Grant No. 40703001)
文摘The carbon and hydrogen isotopic composition of biogenic gas is of great importance for the study of its generation pathway and reservoiring characteristics. In this paper, the formation pathways and reservoiring characteristics of biogenic gas reservoirs in China are described in terms of the carbon and hydrogen isotopic compositions of 31 gas samples from 10 biogenic gas reservoirs. The study shows that the hydrogen isotopic compositions of these biogenic gas reservoirs can be divided into three intervals: δDCH4>-200‰,-250‰<δDCH4<-200‰ and δDCH4<-250‰. The forerunners believed that the main generation pathway of biogenic gas under the condition of continental fresh water is acetic fermentation. Our research results showed that the generation pathway of biogenic gas under the condition of marine facies is typical CO2-reduction, the biogenic gas has heavy hydrogen isotopic composition: its δDCH4 values are higher than-200‰; that the biogenic gas under the condition of continental facies also was generated by the same way, but its hydrogen isotopic composition is lighter than that of biogenetic gas generated under typical marine facies condition: -250‰<δDCH4<-200‰, the δDCH4 values may be related to the salinity of the water medium in ancient lakes. From the relevant data of the Qaidam Basin, it can be seen that the hydrogen isotopic composition of biogenic methane has the same variation trend with increasing salinity of water medium. There are biogenic gas reservoirs formed in transitional regions under the condition of continental facies. These gas reservoirs resulted from both CO2-reduction and acetic fermentation, the formation of which may be related to the non-variant salinity of ancient water medium and the relatively high geothermal gradient, as is the case encountered in the Baoshan Basin. The biogenic gas generating in these regions has light hydrogen isotopic composition: δDCH4<-250‰, and relatively heavy carbon isotopic composition. There is a fairly strong negative correlation b
基金This study was supported by the Special Funds for Strategic Emerging Industry Development of Shenzhen(Grant No.20170922151538732)the Science and Technology Project of Shenzhen(Grant No.JSGG20180703164202084)+2 种基金the Natural Science Foundation Project of China(Grant No.71573022)the National Natural Science Foundation Regional Projects(Grant No.82060440)the special health research projects of 2019 funded by the Chinese PLA General Hospital(Grant No.NLBJ-2019003).
文摘Objective:Hereditary colorectal cancer(CRC)accounts for approximately 5%–10%of all CRC cases.The full profile of CRC-related germline mutations and the corresponding somatic mutational profile have not been fully determined in the Chinese population.Methods:We performed the first population study investigating the germline mutation status in more than 1,000(n=1,923)Chinese patients with CRC and examined their relationship with the somatic mutational landscape.Germline alterations were examined with a 58-gene next-generation sequencing panel,and somatic alterations were examined with a 605-gene panel.Results:A total of 92 pathogenic(P)mutations were identified in 85 patients,and 81 likely pathogenic(LP)germline mutations were identified in 62 patients,accounting for 7.6%(147/1,923)of all patients.MSH2 and APC was the most mutated gene in the Lynch syndrome and non-Lynch syndrome groups,respectively.Patients with P/LP mutations had a significantly higher ratio of microsatellite instability,highly deficient mismatch repair,family history of CRC,and lower age.The somatic mutational landscape revealed a significantly higher mutational frequency in the P group and a trend toward higher copy number variations in the non-P group.The Lynch syndrome group had a significantly higher mutational frequency and tumor mutational burden than the nonLynch syndrome group.Clustering analysis revealed that the Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Population risk analysis indicated that the overall odds ratio was 11.13(95%CI:8.289–15.44)for the P group and 20.68(95%CI:12.89–33.18)for the LP group.Conclusions:Distinct features were revealed in Chinese patients with CRC with germline mutations.The Notch signaling pathway was uniquely clustered in the Lynch syndrome group,and the MAPK and cAMP signaling pathways were uniquely clustered in the non-Lynch syndrome group.Patients with P/LP germline muta
基金Supported by the China National Science and Technology Major Project(2017ZX05008-006)
文摘Migration and accumulation simulation of oil and gas in carrier systems has always been a difficult subject in the quantitative study of petroleum geology. In view of the fact that the traditional geological modeling technology can not establish the interrelation of carriers in three dimensional space, we have proposed a hybrid-dimensional mesh modeling technology consisting of body(stratum), surfaces(faults and unconformities), lines and points, which provides an important research method for the description of geometry of sand bodies, faults and unconformities, the 3 D geological modeling of complex tectonic areas, and the simulation of hydrocarbon migration and accumulation. Furthermore, we have advanced a 3 D hydrocarbon migration pathway tracking method based on the hybrid-dimensional mesh of the carrier system. The application of this technology in western Luliang Uplift of Junggar Basin shows that the technology can effectively characterize the transport effect of fault planes, unconformities and sand bodies, indicate the hydrocarbon migration pathways, simulate the process of oil accumulation, reservoir adjustment and secondary reservoir formation, predict the hydrocarbon distribution. It is found through the simulation that the areas around the paleo-oil reservoir and covered by migration pathways are favorable sites for oil and gas distribution.
基金supported by Ministry of Education,Universities and Research(MIUR/FIRB)funding to PC
文摘The current idea behind brain pathology is that disease is initiated by mild disturbances of common physiological processes. Overtime, the disruption of the neuronal homeostasis will determine irreversible degeneration and neuronal apoptosis. This could be also true in the case of nerve growth factor （NGF） al- terations in sporadic Alzheimer＇s disease （AD）, an age-related pathology characterized by cholinergic loss, amyloid plaques and neurofibrillary tangles. In fact, the pathway activated by NGF, a key neurotrophin for the metabolism of basal forebrain cholinergic neurons （BFCN）, is one of the first homeostatic systems affected in prodromal AD. NGF signaling dysfunctions have been thought for decades to occur in AD late stages, as a mere consequence of amyloid-driven disruption of the retrograde axonal transport of neuro- trophins to BFCN. Nowadays, a wealth of knowledge is potentially opening a new scenario： NGF signaling impairment occurs at the onset of AD and correlates better than amyloid load with cognitive decline. The recent acceleration in the characterization of anatomical, functional and molecular profiles of early AD is aimed at maximizing the efficacy of existing treatments and setting novel therapies. Accordingly, the elucidation of the molecular events underlying APP metabolism regulation by the NGF pathway in the sep- to-hippocampal system is crucial for the identification of new target molecules to slow and eventually halt mild cognitive impairment （MCI） and its progression toward AD.
