Although climate change has convincingly been linked to the evolution of human civilization on different temporal scales,its role in influencing the spatial patterns of ancient civilizations has rarely been investigat...Although climate change has convincingly been linked to the evolution of human civilization on different temporal scales,its role in influencing the spatial patterns of ancient civilizations has rarely been investigated,The northward shift of the ancient Silk Road(SR)route from the Tarim Basin(TB)to the Junggar Basin during~420-850 CE provides the opportunity to investigate the relationship between climate change and the spatial evolution of human societies.Here,we use a new high-resolution chironomidbased temperature reconstruction from arid China,combined with hydroclimatic and historical datasets,to assess the possible effects of climate fluctuations on the shift of the ancient SR route,We found that a cooling/drying climate in the TB triggered the SR route shift during~420-600 CE,However,a warming/wetting climate during~600-850 CE did not inhibit this shift,but instead promoted it,because of the favorable climate-induced geopolitical conflicts between the Tubo Kingdom and the Tang Dynasty in the TB.Our findings reveal two distinct ways in which climate change drove the spatial evolution of human civilization,and they demonstrate the flexibility of societal responses to climate change.展开更多
Sequence tag index in the field of computational proteomics can be used to facilitate faster open-search-based identification of modified peptides and in-depth analysis of mass spectrometry data. In protein-identifica...Sequence tag index in the field of computational proteomics can be used to facilitate faster open-search-based identification of modified peptides and in-depth analysis of mass spectrometry data. In protein-identification search engines, sequence tag index are playing a prominent role in recent ten years due to fast searching speed. However, in pursuit of less index space consumption, some protein search engines design excessively concise index schemes which lead to higher computational burden. We proposed a new tag index scheme named TIIP with a better balance between space and time complexity. TIIP has a unique two-level hierarchical index structure which allows rapid retrieval of all peptide sequences and their corresponding masses. Theoretically, the index space consumption of TIIP is not much higher compared to the typical tag index schemes, but the time complexity of sequence retrieval can be reduced to O(1), and practically, TIIP has about one million fold improvement in searching speed compared with brute force approach.展开更多
基金supported by the National Key R&D Program of China(2018YFA0606404)the National Natural Science Foundation of China(42371172,41822102)+1 种基金the State Key Laboratory of Cryospheric Science(SKLCS-ZZ-2023)the Foundation for Excellent Youth Scholars of NIEER,CAS(FEYS2019009).
文摘Although climate change has convincingly been linked to the evolution of human civilization on different temporal scales,its role in influencing the spatial patterns of ancient civilizations has rarely been investigated,The northward shift of the ancient Silk Road(SR)route from the Tarim Basin(TB)to the Junggar Basin during~420-850 CE provides the opportunity to investigate the relationship between climate change and the spatial evolution of human societies.Here,we use a new high-resolution chironomidbased temperature reconstruction from arid China,combined with hydroclimatic and historical datasets,to assess the possible effects of climate fluctuations on the shift of the ancient SR route,We found that a cooling/drying climate in the TB triggered the SR route shift during~420-600 CE,However,a warming/wetting climate during~600-850 CE did not inhibit this shift,but instead promoted it,because of the favorable climate-induced geopolitical conflicts between the Tubo Kingdom and the Tang Dynasty in the TB.Our findings reveal two distinct ways in which climate change drove the spatial evolution of human civilization,and they demonstrate the flexibility of societal responses to climate change.
文摘Sequence tag index in the field of computational proteomics can be used to facilitate faster open-search-based identification of modified peptides and in-depth analysis of mass spectrometry data. In protein-identification search engines, sequence tag index are playing a prominent role in recent ten years due to fast searching speed. However, in pursuit of less index space consumption, some protein search engines design excessively concise index schemes which lead to higher computational burden. We proposed a new tag index scheme named TIIP with a better balance between space and time complexity. TIIP has a unique two-level hierarchical index structure which allows rapid retrieval of all peptide sequences and their corresponding masses. Theoretically, the index space consumption of TIIP is not much higher compared to the typical tag index schemes, but the time complexity of sequence retrieval can be reduced to O(1), and practically, TIIP has about one million fold improvement in searching speed compared with brute force approach.