The scarcity of in-situ ocean observations poses a challenge for real-time information acquisition in the ocean.Among the crucial hydroacoustic environmental parameters,ocean sound velocity exhibits significant spatia...The scarcity of in-situ ocean observations poses a challenge for real-time information acquisition in the ocean.Among the crucial hydroacoustic environmental parameters,ocean sound velocity exhibits significant spatial and temporal variability and it is highly relevant to oceanic research.In this study,we propose a new data-driven approach,leveraging deep learning techniques,for the prediction of sound velocity fields(SVFs).Our novel spatiotemporal prediction model,STLSTM-SA,combines Spatiotemporal Long Short-Term Memory(ST-LSTM) with a self-attention mechanism to enable accurate and real-time prediction of SVFs.To circumvent the limited amount of observational data,we employ transfer learning by first training the model using reanalysis datasets,followed by fine-tuning it using in-situ analysis data to obtain the final prediction model.By utilizing the historical 12-month SVFs as input,our model predicts the SVFs for the subsequent three months.We compare the performance of five models:Artificial Neural Networks(ANN),Long ShortTerm Memory(LSTM),Convolutional LSTM(ConvLSTM),ST-LSTM,and our proposed ST-LSTM-SA model in a test experiment spanning 2019 to 2022.Our results demonstrate that the ST-LSTM-SA model significantly improves the prediction accuracy and stability of sound velocity in both temporal and spatial dimensions.The ST-LSTM-SA model not only accurately predicts the ocean sound velocity field(SVF),but also provides valuable insights for spatiotemporal prediction of other oceanic environmental variables.展开更多
A set of low-grade clastic metamorphic and carbonate rocks,and greenschists outcropping in the southwestern(SW)margin of the North China Craton(NCC),was originally classified as the Paleoproterozoic Xiong’er Group ac...A set of low-grade clastic metamorphic and carbonate rocks,and greenschists outcropping in the southwestern(SW)margin of the North China Craton(NCC),was originally classified as the Paleoproterozoic Xiong’er Group according to stratigraphic correlation.To verify the age,this paper carried out detrital zircon U–Pb LA-ICP-MS dating of low-grade clastic metamorphic rocks exposed in the Changqing area at the SW margin of the Ordos Block in the SW part of the NCC.Results from detrital zircon dating indicate that the metamorphic and carbonate rocks can be classified into the Neoproterozoic Nanhua System,which is the only Nanhua System stratum in this block so far,and it probably could provide new clues to Rodinia break-up and Snowball Earth of the NCC.The nine peak ages of the low-grade clastic metamorphic rocks reflected its relatively complex provenance,and almost all major geological events experienced by the NCC basement since the Neoarchean,but some age peaks were difficult to correspond to that of the NCC,indicating that the southwestern part of the Ordos Block was also affected by the Qinling and Qiliang orogenic belts during Nanhua System of Neoproterozoic.Combined with provenance analysis,it was revealed that the current southwest boundary of the Ordos Block was the previous southwest boundary of the Ordos Block during the Qingbaikou-Nanhua Period of the Neoproterozoic.展开更多
The rock association of low-grade metasedimentary rocks and greenschists located within the Meso- Cenozoic Liupanshan Fault system on the southwestern margin of the North China Craton (NCC)is regarded as part of the P...The rock association of low-grade metasedimentary rocks and greenschists located within the Meso- Cenozoic Liupanshan Fault system on the southwestern margin of the North China Craton (NCC)is regarded as part of the Paleoproterozoic Xiong'er Group.These low- grade rocks are separated by normal faults,with the greenschist located in the hanging wails.Zircon LA-ICP- MS U-Pb ages of the greenschists range from 2455 to 423 Ma,suggesting that they are not Paleoproterozoic in age. The protolith ages (206-194 Ma)of the greenschists were determined by LA-ICP-MS U-Pb dating of zircons from two siltstone inteflayers.The petrology and geochemistry of the greenschists reveal that their protolith was continental tholeiitic basalt that formed in an extensional environment such as a continental rift.Thus,it is proposed that the protolith of the greenschists was a mafic volcanic rock of Late Triassic-Early Jurassic age and was metamorphosed during the Jurassic due to tectonism within the Liupanshan tectonic belt.These results show that the greenschists should be reclassified and removed from the Xiong'er Group,and explains why they differ so much from those of typical Xiong'er Group successions in other areas.The formation of the mafic volcanic rocks under conditions of continental rifting differs from that of coeval granitic rocks in the western Qinling Orogen,where the extension occurred during a post-collisional stage in the Late Triassic,which further suggests that the southwestern margin of the NCC became an extensional setting after the Late Triassic.展开更多
Camelid single-domain antibody fragments(nanobodies)are an emerging force in therapeutic biopharmaceuticals and clinical diagnostic reagents in recent years.Nearly all nanobodies available to date have been obtained b...Camelid single-domain antibody fragments(nanobodies)are an emerging force in therapeutic biopharmaceuticals and clinical diagnostic reagents in recent years.Nearly all nanobodies available to date have been obtained by animal immunization,a bottleneck restricting the large-scale application of nanobodies.In this study,we developed three kinds of gene designatedregion pan-editing(GDP)technologies to introduce multiple mutations in complementarity-determining regions(CDRs)of nanobodies in vitro.Including the integration of G-quadruplex fragments in CDRs,which induces the spontaneous multiple mutations in CDRs;however,these mutant sequences are highly similar,resulting in a lack of sequences diversity in the CDRs.We also used CDR-targeting traditional gRNA-guided base-editors,which effectively diversify the CDRs.And most importantly,we developed the self-assembling gRNAs,which are generated by reprogrammed tracrRNA hijacking of endogenous mRNAs as crRNAs.Using base-editors guided by self-assembling gRNAs,we can realize the iteratively diversify the CDRs.And we believe the last GDP technology is highly promising in immunization-free nanobody library construction,and the full development of this novel nanobody discovery platform can realize the synthetic evolution of nanobodies in vitro.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.42004030)Basic Scientific Fund for National Public Research Institutes of China(Grant No.2022S03)+1 种基金Science and Technology Innovation Project(LSKJ202205102)funded by Laoshan Laboratory,and the National Key Research and Development Program of China(2020YFB0505805).
文摘The scarcity of in-situ ocean observations poses a challenge for real-time information acquisition in the ocean.Among the crucial hydroacoustic environmental parameters,ocean sound velocity exhibits significant spatial and temporal variability and it is highly relevant to oceanic research.In this study,we propose a new data-driven approach,leveraging deep learning techniques,for the prediction of sound velocity fields(SVFs).Our novel spatiotemporal prediction model,STLSTM-SA,combines Spatiotemporal Long Short-Term Memory(ST-LSTM) with a self-attention mechanism to enable accurate and real-time prediction of SVFs.To circumvent the limited amount of observational data,we employ transfer learning by first training the model using reanalysis datasets,followed by fine-tuning it using in-situ analysis data to obtain the final prediction model.By utilizing the historical 12-month SVFs as input,our model predicts the SVFs for the subsequent three months.We compare the performance of five models:Artificial Neural Networks(ANN),Long ShortTerm Memory(LSTM),Convolutional LSTM(ConvLSTM),ST-LSTM,and our proposed ST-LSTM-SA model in a test experiment spanning 2019 to 2022.Our results demonstrate that the ST-LSTM-SA model significantly improves the prediction accuracy and stability of sound velocity in both temporal and spatial dimensions.The ST-LSTM-SA model not only accurately predicts the ocean sound velocity field(SVF),but also provides valuable insights for spatiotemporal prediction of other oceanic environmental variables.
基金funded by National Natural Science Foundation of China(Grant No.42072231).
文摘A set of low-grade clastic metamorphic and carbonate rocks,and greenschists outcropping in the southwestern(SW)margin of the North China Craton(NCC),was originally classified as the Paleoproterozoic Xiong’er Group according to stratigraphic correlation.To verify the age,this paper carried out detrital zircon U–Pb LA-ICP-MS dating of low-grade clastic metamorphic rocks exposed in the Changqing area at the SW margin of the Ordos Block in the SW part of the NCC.Results from detrital zircon dating indicate that the metamorphic and carbonate rocks can be classified into the Neoproterozoic Nanhua System,which is the only Nanhua System stratum in this block so far,and it probably could provide new clues to Rodinia break-up and Snowball Earth of the NCC.The nine peak ages of the low-grade clastic metamorphic rocks reflected its relatively complex provenance,and almost all major geological events experienced by the NCC basement since the Neoarchean,but some age peaks were difficult to correspond to that of the NCC,indicating that the southwestern part of the Ordos Block was also affected by the Qinling and Qiliang orogenic belts during Nanhua System of Neoproterozoic.Combined with provenance analysis,it was revealed that the current southwest boundary of the Ordos Block was the previous southwest boundary of the Ordos Block during the Qingbaikou-Nanhua Period of the Neoproterozoic.
基金the National Natural Science Foundation of China (Grant No.41421002)MOST Special Fund from the State Key Laboratory of Continental Dynamics,Northwest University.
文摘The rock association of low-grade metasedimentary rocks and greenschists located within the Meso- Cenozoic Liupanshan Fault system on the southwestern margin of the North China Craton (NCC)is regarded as part of the Paleoproterozoic Xiong'er Group.These low- grade rocks are separated by normal faults,with the greenschist located in the hanging wails.Zircon LA-ICP- MS U-Pb ages of the greenschists range from 2455 to 423 Ma,suggesting that they are not Paleoproterozoic in age. The protolith ages (206-194 Ma)of the greenschists were determined by LA-ICP-MS U-Pb dating of zircons from two siltstone inteflayers.The petrology and geochemistry of the greenschists reveal that their protolith was continental tholeiitic basalt that formed in an extensional environment such as a continental rift.Thus,it is proposed that the protolith of the greenschists was a mafic volcanic rock of Late Triassic-Early Jurassic age and was metamorphosed during the Jurassic due to tectonism within the Liupanshan tectonic belt.These results show that the greenschists should be reclassified and removed from the Xiong'er Group,and explains why they differ so much from those of typical Xiong'er Group successions in other areas.The formation of the mafic volcanic rocks under conditions of continental rifting differs from that of coeval granitic rocks in the western Qinling Orogen,where the extension occurred during a post-collisional stage in the Late Triassic,which further suggests that the southwestern margin of the NCC became an extensional setting after the Late Triassic.
基金the National Natural Science Foundation of China(Grant 81902916)Natural Science Foundation of Henan Province(222300420513)+1 种基金National Key R&D Program of China(2019YFA0906000)National Natural Science Foundation of China(Grant 81903187 and 82003261).
文摘Camelid single-domain antibody fragments(nanobodies)are an emerging force in therapeutic biopharmaceuticals and clinical diagnostic reagents in recent years.Nearly all nanobodies available to date have been obtained by animal immunization,a bottleneck restricting the large-scale application of nanobodies.In this study,we developed three kinds of gene designatedregion pan-editing(GDP)technologies to introduce multiple mutations in complementarity-determining regions(CDRs)of nanobodies in vitro.Including the integration of G-quadruplex fragments in CDRs,which induces the spontaneous multiple mutations in CDRs;however,these mutant sequences are highly similar,resulting in a lack of sequences diversity in the CDRs.We also used CDR-targeting traditional gRNA-guided base-editors,which effectively diversify the CDRs.And most importantly,we developed the self-assembling gRNAs,which are generated by reprogrammed tracrRNA hijacking of endogenous mRNAs as crRNAs.Using base-editors guided by self-assembling gRNAs,we can realize the iteratively diversify the CDRs.And we believe the last GDP technology is highly promising in immunization-free nanobody library construction,and the full development of this novel nanobody discovery platform can realize the synthetic evolution of nanobodies in vitro.
