The hadal zone-Earth’s deepest oceanic trenches below 6,000 meters-has long been considered a lifeless abyss.Researchers from the Institute of Hydrobiology(IHB)and the Institute of Deep-Sea Science and Engineering(ID...The hadal zone-Earth’s deepest oceanic trenches below 6,000 meters-has long been considered a lifeless abyss.Researchers from the Institute of Hydrobiology(IHB)and the Institute of Deep-Sea Science and Engineering(IDSSE),both under the Chinese Academy of Sciences,together with collaborators from Northwestern Polytechnical University,recently decoded how fish thrive in this extreme realm through two evolutionary pathways while uncovering alarming traces of human pollution in these pristine ecosystems.Their discovery was published in Cell on March 6,2025.展开更多
Sequence similarities were found between protein and DNA sequences encoding certain part of conserved variable immunoglobulin domains (i.e. conserved IgV) and phosphorylation sites. Hypermutation motifs were then indi...Sequence similarities were found between protein and DNA sequences encoding certain part of conserved variable immunoglobulin domains (i.e. conserved IgV) and phosphorylation sites. Hypermutation motifs were then indicated in the majority of the corresponding non-IgV nucleotide sequences. According to database confirmations or double prediction of phosphorylation sites, 80% of the selected human and mouse IgV-related phosphorylation sites or their highly probable candidates exhibited substrate relationship to ataxia-telangiectasia-mutated kinase known as ATM. In accordance with literature data, inactivation of ATM by mutations can participate in the mechanisms of carcinogenesis, neurodegeneration and possibly also in aging. In agreement with this relationship, some of the selected IgV-/ATM-related segments formed molecules specifically involved in carcinogenesis. The selected IgV-related sequence segments were also similar to certain segments of higher plants containing immunoglobulin-like repeats and related regions. Bioinformatic analysis of some selected plant sequences then indicated the presence of catalytic domains composing serine/threonine/tyrosine receptor/receptor-like kinases, which are considered important structures for evolution of very early and part of later Ig-domain-related immunity. The analyzed conserved domain similarities also suggested certain interesting structural and phylogenic relationships, which need to be further investigated. This review in fact briefly summarizes the findings on the subject from the last twenty years.展开更多
Combined data of physical property, benthic foraminifera, and stable isotopes from ODP Sites 1148, 1146, and 1143 are used to discuss deep water evolution in the South China Sea （SCS） since the Early Miocene. The re...Combined data of physical property, benthic foraminifera, and stable isotopes from ODP Sites 1148, 1146, and 1143 are used to discuss deep water evolution in the South China Sea （SCS） since the Early Miocene. The results indicate that 3 lithostratigraphic units, respectively corresponding to 21-17 Ma, 15-10 Ma, and 10-5 Ma with positive red parameter （a^＊） marking the red brown sediment color represent 3 periods of deep water ventilation. The first 2 periods show a closer link to contemporary production of the Antarctic Bottom Water （AABW） and Northern Component Water（NCW）, indicating a free connection of deep waters between the SCS and the open ocean before 10 Ma.After 10 Ma, red parameter dropped but stayed higher than the modern value （a^＊=0）, the CaCO3 percentage difference between Site 1148 from a lower deepwater setting and Site 1146 from an upper deepwater setting enlarged significantly, and benthic species which prefer oxygen-rich bottom conditions dramatically decreased. Coupled with a major negative excursion of benthic δ^13Cat ～10 Ma,these parameters may denote a weakening in the control of the SCS deep water by the open ocean.Probably they mark the birth of a local deep water due to shallow waterways or rise of sill depths during the course of sea basin closing from south to east by the west-moving Philippine Arc after the end of SCS seafloor spreading at 16-15 Ma. However, it took another 5 Ma before the dissolved oxygen approached close to the modern level. Although the oxygen level continued to stabilize, several Pacific Bottom Water （PBW） and Pacific Deep Water （PDW） marker species rapidly increased since ～6 Ma,followed by a dramatic escalation in planktonic fragmentation which indicates high dissolution especially after ～5 Ma. The period of 5-3 Ma saw the strongest stratified deepwater in the then SCS, as indicated by up to 40﹪ CaCO3 difference between Sites 1148 and 1146. Apart from a strengthening PDW as a result of global cooling and ice cap buildup on northern high latitudes, a deepening sea basin due to stronger subduction eastward may also have triggered the influx of more corrosive waters from the deep western Pacific. Since 3 Ma, the evolution of the SCS deep water entered a modern phase, as characterized by relative stable 10﹪ CaCO3 difference between the two sites and increase in infaunal benthic species which prefer a low oxygenated environment. The subsequent reduction of PBW and PDW marker species at about 1.2 Ma and 0.9 Ma and another significant negative excursion of benthic δ^13Cto a Neogene minimum at ～0.9 Ma together convey a clear message that the PBW largely disappeared and the PDW considerably weakened in the Mid-Pleistocene SCS. Therefore, the true modern mode SCS deep water started to form only during the ＂Mid-Pleistocene climatic transition＂ probably due to the rise of sill depths under the Bashi Strait.展开更多
Two batches of Bi‐2212 precursor powder with Sr/Ca=2.24,2.33 were prepared by the spray pyrolysis tech-nology.Then two Bi‐2212 superconducting wires marked as Line4 and Line8‐2 were prepared by the above powders.Li...Two batches of Bi‐2212 precursor powder with Sr/Ca=2.24,2.33 were prepared by the spray pyrolysis tech-nology.Then two Bi‐2212 superconducting wires marked as Line4 and Line8‐2 were prepared by the above powders.Line4 with Sr/Ca=2.24 showed much higher phase purity,higher texture and its critical current density(J_(c))was 1.5 times that of Line8‐2 with Sr/Ca=2.33.Their micro‐structure evolution was scrutinized by quenching each wire at 7 instantaneous moments during the partial melting process(PMP).Bi‐2212 was found to decompose into(Sr,Ca)_(14)Cu_(24)O_(x)(14:24AEC),Bi_(9)Sr_(11)Ca_(5)O_(x)(9:16CF),Bi‐rich liquid Bi‐2212 and Bi‐rich solid Bi‐2212 at the initial stage of PMP.When Bi‐2212 began to solidify,the above four phases reacted to generate Bi‐2212.By analyzing the particle size,the content and the composition variation for 14:24AEC,9:16CF as well as the composition variation for Bi‐2212 matrix in above 7 moments of PMP,the phase evolu-tion’s difference between two wires was finally confirmed.The formation energy of 14:24AEC was smaller compared with 9:16CF,while 9:16CF was faster on dynamics.14:24AEC determined the whole synthetic reac-tion’s rate of Bi‐2212,and Sr/Ca as well as its value fluctuation in Bi‐2212 precursor powder can decide both the timeline and the driving force of PMP.A larger Sr/Ca in Line8‐2 made it melt earlier compared with Line4,which led to its earlier timeline during the melting stage of PMP.While the more consistent phase evolution’s pace between 14:24AEC and 9:16CF in Line4 finally contributed a larger Sr/Ca after solidification.Both the larger Sr/Ca and its larger fluctuation in Line4 finally contributed to its faster phase evolution’s pace,higher phase purity,better texture and higher J_(c).The deep logic driving the phase evolution mechanism in Bi‐2212 wires was disclosed for the first time,which will be very helpful to the future improvement of J_(c)for Bi‐2212 wires.展开更多
文摘The hadal zone-Earth’s deepest oceanic trenches below 6,000 meters-has long been considered a lifeless abyss.Researchers from the Institute of Hydrobiology(IHB)and the Institute of Deep-Sea Science and Engineering(IDSSE),both under the Chinese Academy of Sciences,together with collaborators from Northwestern Polytechnical University,recently decoded how fish thrive in this extreme realm through two evolutionary pathways while uncovering alarming traces of human pollution in these pristine ecosystems.Their discovery was published in Cell on March 6,2025.
文摘Sequence similarities were found between protein and DNA sequences encoding certain part of conserved variable immunoglobulin domains (i.e. conserved IgV) and phosphorylation sites. Hypermutation motifs were then indicated in the majority of the corresponding non-IgV nucleotide sequences. According to database confirmations or double prediction of phosphorylation sites, 80% of the selected human and mouse IgV-related phosphorylation sites or their highly probable candidates exhibited substrate relationship to ataxia-telangiectasia-mutated kinase known as ATM. In accordance with literature data, inactivation of ATM by mutations can participate in the mechanisms of carcinogenesis, neurodegeneration and possibly also in aging. In agreement with this relationship, some of the selected IgV-/ATM-related segments formed molecules specifically involved in carcinogenesis. The selected IgV-related sequence segments were also similar to certain segments of higher plants containing immunoglobulin-like repeats and related regions. Bioinformatic analysis of some selected plant sequences then indicated the presence of catalytic domains composing serine/threonine/tyrosine receptor/receptor-like kinases, which are considered important structures for evolution of very early and part of later Ig-domain-related immunity. The analyzed conserved domain similarities also suggested certain interesting structural and phylogenic relationships, which need to be further investigated. This review in fact briefly summarizes the findings on the subject from the last twenty years.
基金This paper is supported by the National Natural Science Foundation of china (Nos. 40576031, 40476030, 40631007).
文摘Combined data of physical property, benthic foraminifera, and stable isotopes from ODP Sites 1148, 1146, and 1143 are used to discuss deep water evolution in the South China Sea （SCS） since the Early Miocene. The results indicate that 3 lithostratigraphic units, respectively corresponding to 21-17 Ma, 15-10 Ma, and 10-5 Ma with positive red parameter （a^＊） marking the red brown sediment color represent 3 periods of deep water ventilation. The first 2 periods show a closer link to contemporary production of the Antarctic Bottom Water （AABW） and Northern Component Water（NCW）, indicating a free connection of deep waters between the SCS and the open ocean before 10 Ma.After 10 Ma, red parameter dropped but stayed higher than the modern value （a^＊=0）, the CaCO3 percentage difference between Site 1148 from a lower deepwater setting and Site 1146 from an upper deepwater setting enlarged significantly, and benthic species which prefer oxygen-rich bottom conditions dramatically decreased. Coupled with a major negative excursion of benthic δ^13Cat ～10 Ma,these parameters may denote a weakening in the control of the SCS deep water by the open ocean.Probably they mark the birth of a local deep water due to shallow waterways or rise of sill depths during the course of sea basin closing from south to east by the west-moving Philippine Arc after the end of SCS seafloor spreading at 16-15 Ma. However, it took another 5 Ma before the dissolved oxygen approached close to the modern level. Although the oxygen level continued to stabilize, several Pacific Bottom Water （PBW） and Pacific Deep Water （PDW） marker species rapidly increased since ～6 Ma,followed by a dramatic escalation in planktonic fragmentation which indicates high dissolution especially after ～5 Ma. The period of 5-3 Ma saw the strongest stratified deepwater in the then SCS, as indicated by up to 40﹪ CaCO3 difference between Sites 1148 and 1146. Apart from a strengthening PDW as a result of global cooling and ice cap buildup on northern high latitudes, a deepening sea basin due to stronger subduction eastward may also have triggered the influx of more corrosive waters from the deep western Pacific. Since 3 Ma, the evolution of the SCS deep water entered a modern phase, as characterized by relative stable 10﹪ CaCO3 difference between the two sites and increase in infaunal benthic species which prefer a low oxygenated environment. The subsequent reduction of PBW and PDW marker species at about 1.2 Ma and 0.9 Ma and another significant negative excursion of benthic δ^13Cto a Neogene minimum at ～0.9 Ma together convey a clear message that the PBW largely disappeared and the PDW considerably weakened in the Mid-Pleistocene SCS. Therefore, the true modern mode SCS deep water started to form only during the ＂Mid-Pleistocene climatic transition＂ probably due to the rise of sill depths under the Bashi Strait.
基金financially supported by the Key Research and Development Program of Shaanxi(Program No.2023‐YBGY‐428)the National natural Science foundation of China(No.52002333)+2 种基金the Science and Technology Planning Project in Weiyang District of Xi’an(No.202107)the National Key R&D Program of China(Grant No.2021YFB3800201)the National natural Science foundation of China(No.52277029).
文摘Two batches of Bi‐2212 precursor powder with Sr/Ca=2.24,2.33 were prepared by the spray pyrolysis tech-nology.Then two Bi‐2212 superconducting wires marked as Line4 and Line8‐2 were prepared by the above powders.Line4 with Sr/Ca=2.24 showed much higher phase purity,higher texture and its critical current density(J_(c))was 1.5 times that of Line8‐2 with Sr/Ca=2.33.Their micro‐structure evolution was scrutinized by quenching each wire at 7 instantaneous moments during the partial melting process(PMP).Bi‐2212 was found to decompose into(Sr,Ca)_(14)Cu_(24)O_(x)(14:24AEC),Bi_(9)Sr_(11)Ca_(5)O_(x)(9:16CF),Bi‐rich liquid Bi‐2212 and Bi‐rich solid Bi‐2212 at the initial stage of PMP.When Bi‐2212 began to solidify,the above four phases reacted to generate Bi‐2212.By analyzing the particle size,the content and the composition variation for 14:24AEC,9:16CF as well as the composition variation for Bi‐2212 matrix in above 7 moments of PMP,the phase evolu-tion’s difference between two wires was finally confirmed.The formation energy of 14:24AEC was smaller compared with 9:16CF,while 9:16CF was faster on dynamics.14:24AEC determined the whole synthetic reac-tion’s rate of Bi‐2212,and Sr/Ca as well as its value fluctuation in Bi‐2212 precursor powder can decide both the timeline and the driving force of PMP.A larger Sr/Ca in Line8‐2 made it melt earlier compared with Line4,which led to its earlier timeline during the melting stage of PMP.While the more consistent phase evolution’s pace between 14:24AEC and 9:16CF in Line4 finally contributed a larger Sr/Ca after solidification.Both the larger Sr/Ca and its larger fluctuation in Line4 finally contributed to its faster phase evolution’s pace,higher phase purity,better texture and higher J_(c).The deep logic driving the phase evolution mechanism in Bi‐2212 wires was disclosed for the first time,which will be very helpful to the future improvement of J_(c)for Bi‐2212 wires.
