CRISPR (clustered regularly interspaced short palindromic repeats)‐Cas (CRISPR associated protein) systems serve as the adaptive immune system by which prokaryotes defend themselves against phages. It has also been d...CRISPR (clustered regularly interspaced short palindromic repeats)‐Cas (CRISPR associated protein) systems serve as the adaptive immune system by which prokaryotes defend themselves against phages. It has also been developed into a series of powerful gene‐editing tools. As the natural inhibitors of CRISPR‐Cas systems, anti‐CRISPRs (Acrs) can be used as the “off‐switch” for CRISPR‐Cas systems to limit the off‐target effects caused by Cas9. Since the discovery of CRISPR‐Cas systems, much research has focused on the identification, mechanisms and applications of Acrs. In light of the rapid development and scientific significance of this field, this review summarizes the history and research status of Acrs, and considers future applications.展开更多
Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emp...Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is required.This study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling equipment.The study specifically investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency stick-slip.These events not only hinder the efficiency of drilling but also lead to exhaustion and harm to the system’s components since they are difficult to be detected and controlled in real time.The study investigates the dynamic interactions of these vibrations,specifically in their high-frequency modes,usingfield data obtained from measurement while drilling.Thefindings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem performance.The obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control systems.Therefore,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect damage.Moreover,by exploiting thesefindings,the assessment of structural resilience in rotary drilling systems can be enhanced.Furthermore,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efficiency of rotary drilling systems in the petroleum industry.展开更多
Thermus thermophilus is an attractive species in the bioindustry due to its valuable natural products,abundant thermophilic enzymes,and promising fermentation capacities.However,efficient and versatile genome editing ...Thermus thermophilus is an attractive species in the bioindustry due to its valuable natural products,abundant thermophilic enzymes,and promising fermentation capacities.However,efficient and versatile genome editing tools are not available for this species.In this study,we developed an efficient genome editing tool for T.thermophilus HB27 based on its endogenous type IB,I-C,and III-A/B CRISPR-Cas systems.First,we systematically characterized the DNA interference capabilities of the different types of the native CRISPR-Cas systems in T.thermophilus HB27.We found that genomic manipulations such as gene deletion,mutation,and in situ tagging could be easily implemented by a series of genome-editing plasmids carrying an artificial self-targeting mini-CRISPR and a donor DNA responsible for the recombinant recovery.We also compared the genome editing efficiency of different CRISPR-Cas systems and the editing plasmids with donor DNAs of different lengths.Additionally,we developed a reporter gene system for T.thermophilus based on a heat-stableβ-galactosidase gene TTP0042,and constructed an engineered strain with a high production capacity of superoxide dismutases by genome modification.展开更多
The discovery and utilization of RNA-guided surveillance complexes,such as CRISPR-Cas9,for sequencespecific DNA or RNA cleavage,has revolutionised the process of gene modification or knockdown.To optimise the use of t...The discovery and utilization of RNA-guided surveillance complexes,such as CRISPR-Cas9,for sequencespecific DNA or RNA cleavage,has revolutionised the process of gene modification or knockdown.To optimise the use of this technology,an exploratory race has ensued to discover or develop new RNA-guided endonucleases with the most flexible sequence targeting requirements,coupled with high cleavage efficacy and specificity.Here we review the constraints of existing gene editing and assess the merits of exploiting the diversity of CRISPR-Cas effectors as a methodology for surmounting these limitations.展开更多
Background Genome editing has been considered as powerful tool in agricultural fields.However,genome editing progress in cattle has not been fast as in other mammal species,for some disadvantages including long gestat...Background Genome editing has been considered as powerful tool in agricultural fields.However,genome editing progress in cattle has not been fast as in other mammal species,for some disadvantages including long gestational periods,single pregnancy,and high raising cost.Furthermore,technically demanding methods such as microinjection and somatic cell nuclear transfer(SCNT)are needed for gene editing in cattle.In this point of view,electroporation in embryos has been risen as an alternative.Results First,editing efficiency of our electroporation methods were tested for embryos.Presence of mutation on embryo was confirmed by T7E1 assay.With first combination,mutation rates for MSTN and PRNP were 57.6%±13.7%and 54.6%±13.5%,respectively.In case of MSTN/BLG,mutation rates were 83.9%±23.6%for MSTN,84.5%±18.0%for BLG.Afterwards,the double-KO embryos were transferred to surrogates and mutation rate was identified in resultant calves by targeted deep sequencing.Thirteen recipients were transferred for MSTN/PRNP,4 calves were delivered,and one calf underwent an induction for double KO.Ten surrogates were given double-KO embryos for MSTN/BLG,and four of the six calves that were born had mutations in both genes.Conclusions These data demonstrated that production of genome edited cattle via electroporation of RNP could be effectively applied.Finally,MSTN and PRNP from beef cattle and MSTN and BLG from dairy cattle have been born and they will be valuable resources for future precision breeding.展开更多
This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal syste...This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal systems have the heat, permeability and fluid, requiring only drilling down to °C, normal heat flow or decaying radiogenic granite as heat sources, and used in district heating. Medium-temperature (MT) 100°C - 190°C, and high-temperature (HT) 190°C - 374°C resources are mostly at plate boundaries, with volcanic intrusive heat source, used mostly for electricity generation. Single well capacities are °C - 500°C) and a range of depths (1 m to 20 Km), but lack permeability or fluid, thus requiring stimulations for heat extraction by conduction. HVAC is 1 - 2 m deep and shallow geothermal down to 500 m in wells, both capturing °C, with °C are either advanced by geothermal developers at <7 Km depth (Enhanced Geothermal Systems (EGS), drilling below brittle-ductile transition zones and under geothermal fields), or by the Oil & Gas industry (Advanced Geothermal Systems, heat recovery from hydrocarbon wells or reservoirs, Superhot Rock Geothermal, and millimeter-wave drilling down to 20 Km). Their primary aim is electricity generation, relying on closed-loops, but EGS uses fractures for heat exchange with earthquake risks during fracking. Unconventional approaches could be everywhere, with shallow geothermal already functional. The deeper and hotter unconventional alternatives are still experimental, overcoming costs and technological challenges to become fully commercial. Meanwhile, the conventional geothermal resources remain the most proven opportunities for investments and development.展开更多
基金Strategic Priority Research Programs of the Chinese Academy of Sciences,Grant/Award Number:XDA19050301National Natural Science Foundation of China,Grant/Award Number:31601189,81572433 and 81772646+1 种基金Biological Resources Program from Chinese Academy of Sciencesthe Young Elite Scientist Sponsorship Program by CAST,Grant/Award Number:2018QNRC001
文摘CRISPR (clustered regularly interspaced short palindromic repeats)‐Cas (CRISPR associated protein) systems serve as the adaptive immune system by which prokaryotes defend themselves against phages. It has also been developed into a series of powerful gene‐editing tools. As the natural inhibitors of CRISPR‐Cas systems, anti‐CRISPRs (Acrs) can be used as the “off‐switch” for CRISPR‐Cas systems to limit the off‐target effects caused by Cas9. Since the discovery of CRISPR‐Cas systems, much research has focused on the identification, mechanisms and applications of Acrs. In light of the rapid development and scientific significance of this field, this review summarizes the history and research status of Acrs, and considers future applications.
文摘Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and petroleum.To achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is required.This study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling equipment.The study specifically investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency stick-slip.These events not only hinder the efficiency of drilling but also lead to exhaustion and harm to the system’s components since they are difficult to be detected and controlled in real time.The study investigates the dynamic interactions of these vibrations,specifically in their high-frequency modes,usingfield data obtained from measurement while drilling.Thefindings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem performance.The obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control systems.Therefore,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect damage.Moreover,by exploiting thesefindings,the assessment of structural resilience in rotary drilling systems can be enhanced.Furthermore,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efficiency of rotary drilling systems in the petroleum industry.
基金the National Natural Science Foundation of China(32170096)the Fundamental Research Funds for the Central Universities(2662022S KPY001)Cooperation Fund of Huazhong Agricultural University-Agricultural Genomics Institute at Shenzhen(CAAS)(SZYJY2021002).
文摘Thermus thermophilus is an attractive species in the bioindustry due to its valuable natural products,abundant thermophilic enzymes,and promising fermentation capacities.However,efficient and versatile genome editing tools are not available for this species.In this study,we developed an efficient genome editing tool for T.thermophilus HB27 based on its endogenous type IB,I-C,and III-A/B CRISPR-Cas systems.First,we systematically characterized the DNA interference capabilities of the different types of the native CRISPR-Cas systems in T.thermophilus HB27.We found that genomic manipulations such as gene deletion,mutation,and in situ tagging could be easily implemented by a series of genome-editing plasmids carrying an artificial self-targeting mini-CRISPR and a donor DNA responsible for the recombinant recovery.We also compared the genome editing efficiency of different CRISPR-Cas systems and the editing plasmids with donor DNAs of different lengths.Additionally,we developed a reporter gene system for T.thermophilus based on a heat-stableβ-galactosidase gene TTP0042,and constructed an engineered strain with a high production capacity of superoxide dismutases by genome modification.
基金the National Health and Medical Research Council of Australia(Grant No.APP1143008)the Australian Research Council(Grant No.DP180101494)the National Natural Science Foundation of China(Grant No.81772214).
文摘The discovery and utilization of RNA-guided surveillance complexes,such as CRISPR-Cas9,for sequencespecific DNA or RNA cleavage,has revolutionised the process of gene modification or knockdown.To optimise the use of this technology,an exploratory race has ensued to discover or develop new RNA-guided endonucleases with the most flexible sequence targeting requirements,coupled with high cleavage efficacy and specificity.Here we review the constraints of existing gene editing and assess the merits of exploiting the diversity of CRISPR-Cas effectors as a methodology for surmounting these limitations.
基金financially supported by the National Research Foundation of Korea(NRF-2021R1A5A1033157 for SRC program:382 Comparative medicine Disease Research Center,NRF-2021R1F1A105195313)the Research Institute of Veterinary Science,the BK21 Four for Future Veterinary Medicine Leading Education and Research Center,and a Seoul National University(SNU)grant(#550e2020005)。
文摘Background Genome editing has been considered as powerful tool in agricultural fields.However,genome editing progress in cattle has not been fast as in other mammal species,for some disadvantages including long gestational periods,single pregnancy,and high raising cost.Furthermore,technically demanding methods such as microinjection and somatic cell nuclear transfer(SCNT)are needed for gene editing in cattle.In this point of view,electroporation in embryos has been risen as an alternative.Results First,editing efficiency of our electroporation methods were tested for embryos.Presence of mutation on embryo was confirmed by T7E1 assay.With first combination,mutation rates for MSTN and PRNP were 57.6%±13.7%and 54.6%±13.5%,respectively.In case of MSTN/BLG,mutation rates were 83.9%±23.6%for MSTN,84.5%±18.0%for BLG.Afterwards,the double-KO embryos were transferred to surrogates and mutation rate was identified in resultant calves by targeted deep sequencing.Thirteen recipients were transferred for MSTN/PRNP,4 calves were delivered,and one calf underwent an induction for double KO.Ten surrogates were given double-KO embryos for MSTN/BLG,and four of the six calves that were born had mutations in both genes.Conclusions These data demonstrated that production of genome edited cattle via electroporation of RNP could be effectively applied.Finally,MSTN and PRNP from beef cattle and MSTN and BLG from dairy cattle have been born and they will be valuable resources for future precision breeding.
文摘This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal systems have the heat, permeability and fluid, requiring only drilling down to °C, normal heat flow or decaying radiogenic granite as heat sources, and used in district heating. Medium-temperature (MT) 100°C - 190°C, and high-temperature (HT) 190°C - 374°C resources are mostly at plate boundaries, with volcanic intrusive heat source, used mostly for electricity generation. Single well capacities are °C - 500°C) and a range of depths (1 m to 20 Km), but lack permeability or fluid, thus requiring stimulations for heat extraction by conduction. HVAC is 1 - 2 m deep and shallow geothermal down to 500 m in wells, both capturing °C, with °C are either advanced by geothermal developers at <7 Km depth (Enhanced Geothermal Systems (EGS), drilling below brittle-ductile transition zones and under geothermal fields), or by the Oil & Gas industry (Advanced Geothermal Systems, heat recovery from hydrocarbon wells or reservoirs, Superhot Rock Geothermal, and millimeter-wave drilling down to 20 Km). Their primary aim is electricity generation, relying on closed-loops, but EGS uses fractures for heat exchange with earthquake risks during fracking. Unconventional approaches could be everywhere, with shallow geothermal already functional. The deeper and hotter unconventional alternatives are still experimental, overcoming costs and technological challenges to become fully commercial. Meanwhile, the conventional geothermal resources remain the most proven opportunities for investments and development.
