Dear Sir, I am Dr. Zhi-Qing Li from Tianjin Medical University Eye Hospital, Tianjin City, China. I write to present a case with hiding iris neovascularization (INV) following central retinal vein occlusion (CRVO) can...Dear Sir, I am Dr. Zhi-Qing Li from Tianjin Medical University Eye Hospital, Tianjin City, China. I write to present a case with hiding iris neovascularization (INV) following central retinal vein occlusion (CRVO) can be detected early by iris angiography (IA) and neovascular glaucoma (NVG) was展开更多
Cre/loxP technology has been widely used to study cell type-specific functions of genes. Proper interpretation of such data critically depends on a clear understanding of the tissue specificity of Cre expression. The ...Cre/loxP technology has been widely used to study cell type-specific functions of genes. Proper interpretation of such data critically depends on a clear understanding of the tissue specificity of Cre expression. The Dmpl- Cre mouse, expressing Cre from a 14-kb DNA fragment of the mouse Dmpl gene, has become a common tool for studying gene function in osteocytes, but the presumed cell specificity is yet to be fully established. By using the Ai9 reporter line that expresses a red fluorescent protein upon Cre recombination, we find that in 2-month-old mice, Dmpl-Cre targets not only osteocytes within the bone matrix but also osteoblasts on the bone surface and preosteoblasts at the metaphyseal chondro-osseous junction. In the bone marrow, Cre activity is evident in certain stromal cells adjacent to the blood vessels, but not in adipocytes. Outside the skeleton, Dmpl-Cre marks not only the skeletal muscle fibers, certain cells in the cerebellum and the hindbrain but also gastric and intestinal mesenchymal cells that express Pdgfra. Confirming the utility of Dmpl-Cre in the gastrointestinal mesenchyme, deletion of Bmprla with Dmpl-Cre causes numerous large polyps along the gastrointestinal tract, consistent with prior work involving inhibition of BMP signaling. Thus, caution needs to be exercised when using Dmpl-Cre because it targets not only the osteoblast lineage at an earlier stage than previously appreciated, but also a number of non-skeletal cell types.展开更多
Plant mitochondrial phosphate transporters regulate phosphate transport and ATP synthesis. Determining whether they function in abiotic stress response process would shed light on their response to salt stress. We use...Plant mitochondrial phosphate transporters regulate phosphate transport and ATP synthesis. Determining whether they function in abiotic stress response process would shed light on their response to salt stress. We used the CRISPR/Cas9 gene-editing system to mutagenize two mitochondrial phosphate transporters, OsMPT3;1 and OsMPT3;2, to investigate their regulatory roles under salt stress. Two cas9(CRISPR-associated protein9)-free homozygous mutants, mpt33 and mpt30, were confirmed to be stable. Both OsMPT3;1 and OsMPT3;2 were markedly induced by salt stress, and their mutagenesis strongly inhibited growth and development, especially under salt stress. Mutagenesis sharply reduced the accumulation of ATP, phosphate, calcium, soluble sugar, and proline and increased osmotic potential, malondialdehyde, and Na^+ /K^+ ratio under salt stress. Both mutants demonstrate normal growth and development in the presence of ATP, revealing high sensitivity to exogenous ATP under salt stress. The mutants showed lowered rates of Na^+ efflux but also of K^+ and Ca^(2+) influx under salt stress. Mutagenesis of OsMPT3;2 altered the enrichment profiles of differentially expressed genes involved mainly in synthesis of secondary metabolites, metabolism of glycolysis, pyruvate, tricarboxylic acid cycle, in response to salt stress. The mutant displayed significant accumulation differences in 14 metabolites involved in 17 metabolic pathways, and strongly up-regulated the accumulation of glutamine, a precursor in proline synthesis, under salt stress. These findings suggest that the OsMPT3 gene modulates phosphate transport and energy supply for ATP synthesis and triggers changes in accumulation of ions and metabolites participating in osmotic regulation in rice under salt stress, thus increasing rice salt tolerance. This study demonstrates the effective application of CRISPR/Cas9 gene-editing to the investigation of plant functional genes.展开更多
In the present study, we used a proteomics approach based on a two-dimensional electrophoresis (2-DE) reference map to investigate protein expression in the ovarian tissues of pubertal Swiss-Webster mice subjected t...In the present study, we used a proteomics approach based on a two-dimensional electrophoresis (2-DE) reference map to investigate protein expression in the ovarian tissues of pubertal Swiss-Webster mice subjected to carbon ion radiation (CIR). Among the identified proteins, ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) is associated with the cell cycle[1] and that it influences proliferation in ovarian tissues. We analyzed the expression of UCH-L1 and the proliferation marker proliferation cell nuclear antigen (PCNA) following CIR using immunoblotting and immunofluorescence. The proteomics and biochemical results provide insight into the underlying mechanisms of CIR toxicity in ovarian tissues.展开更多
This is the fifth year since the first "Chinese Enterprises Competitiveness Annual Meeting" convened in 2003. During those five years,we have witnessed a period of remarkable performance by Chinese enterpris...This is the fifth year since the first "Chinese Enterprises Competitiveness Annual Meeting" convened in 2003. During those five years,we have witnessed a period of remarkable performance by Chinese enterprises. These last five years have seen a reaping of the fruits brought about by China's three-decade-long reform and opening, as evidenced by the increasing growth and maturity of Chinese enterprises and the rising competitiveness of publicly listed Chinese enterprises. Along with the development of globalization initiatives, Chinese enterprises are moving firmly and solidly towards internationalization and have begun to have a profound impact on the world economy. The roadmap of Chinese enterprises has now become a focus of global attention.展开更多
An international consortium of scientists studying gamma-ray bursts (GRBs) as part of the POLAR (GRB polarimeter) experiment has revealed that high-energy photon emissions from black holes are neither completely chaot...An international consortium of scientists studying gamma-ray bursts (GRBs) as part of the POLAR (GRB polarimeter) experiment has revealed that high-energy photon emissions from black holes are neither completely chaotic nor completely organized, but a mixture.展开更多
The year 2001 saw theconvocation of theFourth National Confer-ence on Work in Tibet.From August to October 2001,we conducted an extensiveinvestigation and study in theurban and rural areas Wewere especially impressed ...The year 2001 saw theconvocation of theFourth National Confer-ence on Work in Tibet.From August to October 2001,we conducted an extensiveinvestigation and study in theurban and rural areas Wewere especially impressed bythe urban expansion in Lhasa,Xigaze and Nyingchi展开更多
The advances and retreats of glaciations through the Pleistocene,especially most recent the Last Glacial Maximum(19-26 thousand years ago),have significantly affected the demographic history,abundance and distribution...The advances and retreats of glaciations through the Pleistocene,especially most recent the Last Glacial Maximum(19-26 thousand years ago),have significantly affected the demographic history,abundance and distribution pattern of modern species.During these glaciations,many species were excluded from large parts of their ranges and forced into refugia by the expanding ice sheets,followed by展开更多
Sacred lotus(Nelumbo nucifera or lotus) is an important aquatic plant in horticulture and ecosystems. As a foundation for exploring genomic variation and evolution among different germplasms, we re-sequenced 19 indivi...Sacred lotus(Nelumbo nucifera or lotus) is an important aquatic plant in horticulture and ecosystems. As a foundation for exploring genomic variation and evolution among different germplasms, we re-sequenced 19 individuals from three cultivated temperate lotus subgroups(rhizome,seed and flower lotus), one wild temperate lotus subgroup(wild lotus), one tropical lotus group(Thai lotus) and an outgroup(Nelumbo lutea). Through genetic diversity and polymorphism analysis by non-missing SNP sites widely distributed in the whole genome, we confirmed that wild and Thai lotus exhibited greater differentiation with a higher genomic diversity compared to cultivated lotus. Rhizome lotus had the lowest genomic diversity and a closer relationship to wild lotus, whereas the genomes of seed and flower lotus were admixed. Genes in energy metabolism process and plant immunity evolved rapidly in lotus, reflecting local adaptation.We established that candidate genes in genomic regions with significant differentiation associated with temperate and tropical lotus divergence always exhibited highly divergent expression pattern. Together, this study comprehensive and credible interpretates important patterns of genetic diversity and relationships, gene evolution, and genomic signature from ecotypic differentiation of sacred lotus.展开更多
Dear Editor :The sustainable cultivation of rice, which serves as staple food crop for more than half of the world's population, is under serious threat due to the huge yield losses inflicted by rice blast disease c...Dear Editor :The sustainable cultivation of rice, which serves as staple food crop for more than half of the world's population, is under serious threat due to the huge yield losses inflicted by rice blast disease caused by the globally destructive fungus Magnaporthe oryzae (Pyricularia oryzae) (Dean et al., 2012; Nalley et al., 2016; Deng et al., 2017). This filamentous ascomycete fungus is also capable of causing blast infection on other economically important cereal crops, including wheat, millet, and barley, making it the world's most important plant pathogenic fungus (Zhong et al., 2016).展开更多
Subject Code:C18 With the support by the National Natural Science Foundation of China,a collaborative study by the research groups led by Prof.Shen Jianzhong(沈建忠)from the College of Veterinary Medicine,China Agricu...Subject Code:C18 With the support by the National Natural Science Foundation of China,a collaborative study by the research groups led by Prof.Shen Jianzhong(沈建忠)from the College of Veterinary Medicine,China Agricultural University and Prof.Timothy R.Walsh from Cardiff University demonstrates the展开更多
Plants, as primary producers, have been playing an indispensable role in other organisms’ survival and the balance of whole ecosystem on Earth. Especially, they provide the main source of energy, food, and medicine f...Plants, as primary producers, have been playing an indispensable role in other organisms’ survival and the balance of whole ecosystem on Earth. Especially, they provide the main source of energy, food, and medicine for human beings, some of which are derived from the primary or secondary metabolites展开更多
Embryonic stem (ES) cells are under precise control of both intrinsic self-renewal gene regulatory network and extrinsic growth factor-triggered signaling cascades.
LepA, the highly conserved translational GTPase (trGTPase), triggers one-codon back-movement of the elongating ribosome. Here we identify a new enzymatic activity
Subject Code:C05With the support by the National Natural Science Foundation of China,a team of scientists let by Profs.Wu Beili(吴蓓丽),Wang Mingwei and Jiang Hualiang from Shanghai Institute of Materia Medica,Chinese...Subject Code:C05With the support by the National Natural Science Foundation of China,a team of scientists let by Profs.Wu Beili(吴蓓丽),Wang Mingwei and Jiang Hualiang from Shanghai Institute of Materia Medica,Chinese Academy of Sciences has determined the high-resolution atomic structure of a full-length class B展开更多
With the support by the National Natural Science Foundation of China and the Chinese Academy of Sciences,the research team led by Prof.Li Junbai(李峻柏)at the CAS Key Lab of Colloid,Interface and Thermodynamics,Instit...With the support by the National Natural Science Foundation of China and the Chinese Academy of Sciences,the research team led by Prof.Li Junbai(李峻柏)at the CAS Key Lab of Colloid,Interface and Thermodynamics,Institute of Chemistry,Chinese Academy of Sciences,revealed the distribution of proteins in the transformation of inorganic/protein hybrid crystals by super-resolution microscopy,which展开更多
Recently,Gary et al.published an article elucidating how sugars contribute to the protection of dry protein structure.They utilized an ingenious liquid-observed vapor exchange(LOVE)nuclear magnetic resonance(NMR)metho...Recently,Gary et al.published an article elucidating how sugars contribute to the protection of dry protein structure.They utilized an ingenious liquid-observed vapor exchange(LOVE)nuclear magnetic resonance(NMR)method,providing valuable insights into the protection mechanism of sugars during the drying process.The details of their study can be found in the article available at https://doi.org/10.1021/acs.biochem.2c00692.展开更多
The economic potential induced by environmental changes in the Arctic region garnered substantial interest,which positions Arctic trade as a crucial indicator in forecasting the impacts of climate change on the global...The economic potential induced by environmental changes in the Arctic region garnered substantial interest,which positions Arctic trade as a crucial indicator in forecasting the impacts of climate change on the global economy.Nevertheless,attention devoted to the evolving dynamics of trade in the Arctic region remains scarce.In this study,we constructed export trade network in the Arctic region(including Denmark,Finland,Sweden,Norway,Iceland,the Canadian Arctic,the Russian Arctic,Alaska State of the USA,and Greenland)from 1990 to 2019 and analyzed its topology and evolutionary characteristics through complex network theory.We used a structural entropy index based on the distribution of the number of trading partners and the degree of trade concentration to assess export diversity,while we also utilized a revealed comparative advantage index to evaluate product export competitiveness using the share of trade volume of each type of product.The results indicate that the total export trade in the Arctic region increased by 53.4%during 1990-2019,with the most significant growth observed in the exports of chemical products and mineral fuels.The increasing complexity of trade network in the Arctic region resulted in the region’s export destinations no longer being concentrated on a few major countries and regions.The proportion of exports from the Arctic region to Europe decreased by 13.5%,while the proportion of exports from the Arctic region to Asia and North America increased by 6.8%and 3.1%,respectively.The Arctic region exhibited clear distinctions in the range of flows of different products,and its export trade was becoming increasingly diversified.Although differences in comparative advantages between products within individual countries or regions have narrowed,substantial gaps persist.The findings of this study can enhance the comprehensive understanding of the significance and function of Arctic trade activities within the global economy,providing a scientific basis for addressing the associated challenges and opportunities in the context of climate change.展开更多
1 In the midst of a stormy night in North Carolina,where rain was pouring down on tin roofs and darkness enveloped the world,an inspiring tale unfolded.Despite the tempests rage,a homeless man appeared as an unsung he...1 In the midst of a stormy night in North Carolina,where rain was pouring down on tin roofs and darkness enveloped the world,an inspiring tale unfolded.Despite the tempests rage,a homeless man appeared as an unsung hero,revealing the depth of the human spirit and the profound connection between the man and his furry(毛茸茸的)companions.展开更多
文摘Dear Sir, I am Dr. Zhi-Qing Li from Tianjin Medical University Eye Hospital, Tianjin City, China. I write to present a case with hiding iris neovascularization (INV) following central retinal vein occlusion (CRVO) can be detected early by iris angiography (IA) and neovascular glaucoma (NVG) was
基金supported by NIH grants AR060456 and AR055923(FL)supported by NIH DK105129,DK094989,by DK052574 to the Washington University Digestive Core Centers(DDRCC)+6 种基金by the pre-Program Project Award from the Siteman Cancer Center Investment Programsupported by the NIGMS cell and Molecular Biology Training Grant(GM007067)supported by the NIH funded George O’Brien Center for Kidney Disease Research(P30DK079333)Kidney translational Research Core and the Renal Division at the Washington University School of Medicinesupported by the Alafi Neuroimaging Laboratorythe Hope Center for Neurological DisordersNIH Shared Instrumentation Grant(S10 RR0227552)to Washington University
文摘Cre/loxP technology has been widely used to study cell type-specific functions of genes. Proper interpretation of such data critically depends on a clear understanding of the tissue specificity of Cre expression. The Dmpl- Cre mouse, expressing Cre from a 14-kb DNA fragment of the mouse Dmpl gene, has become a common tool for studying gene function in osteocytes, but the presumed cell specificity is yet to be fully established. By using the Ai9 reporter line that expresses a red fluorescent protein upon Cre recombination, we find that in 2-month-old mice, Dmpl-Cre targets not only osteocytes within the bone matrix but also osteoblasts on the bone surface and preosteoblasts at the metaphyseal chondro-osseous junction. In the bone marrow, Cre activity is evident in certain stromal cells adjacent to the blood vessels, but not in adipocytes. Outside the skeleton, Dmpl-Cre marks not only the skeletal muscle fibers, certain cells in the cerebellum and the hindbrain but also gastric and intestinal mesenchymal cells that express Pdgfra. Confirming the utility of Dmpl-Cre in the gastrointestinal mesenchyme, deletion of Bmprla with Dmpl-Cre causes numerous large polyps along the gastrointestinal tract, consistent with prior work involving inhibition of BMP signaling. Thus, caution needs to be exercised when using Dmpl-Cre because it targets not only the osteoblast lineage at an earlier stage than previously appreciated, but also a number of non-skeletal cell types.
基金supported by the National Key Research and Development Program of China(2016YFC0501203)the National Genetically Modified Organism Project(2016ZX08010005-9)。
文摘Plant mitochondrial phosphate transporters regulate phosphate transport and ATP synthesis. Determining whether they function in abiotic stress response process would shed light on their response to salt stress. We used the CRISPR/Cas9 gene-editing system to mutagenize two mitochondrial phosphate transporters, OsMPT3;1 and OsMPT3;2, to investigate their regulatory roles under salt stress. Two cas9(CRISPR-associated protein9)-free homozygous mutants, mpt33 and mpt30, were confirmed to be stable. Both OsMPT3;1 and OsMPT3;2 were markedly induced by salt stress, and their mutagenesis strongly inhibited growth and development, especially under salt stress. Mutagenesis sharply reduced the accumulation of ATP, phosphate, calcium, soluble sugar, and proline and increased osmotic potential, malondialdehyde, and Na^+ /K^+ ratio under salt stress. Both mutants demonstrate normal growth and development in the presence of ATP, revealing high sensitivity to exogenous ATP under salt stress. The mutants showed lowered rates of Na^+ efflux but also of K^+ and Ca^(2+) influx under salt stress. Mutagenesis of OsMPT3;2 altered the enrichment profiles of differentially expressed genes involved mainly in synthesis of secondary metabolites, metabolism of glycolysis, pyruvate, tricarboxylic acid cycle, in response to salt stress. The mutant displayed significant accumulation differences in 14 metabolites involved in 17 metabolic pathways, and strongly up-regulated the accumulation of glutamine, a precursor in proline synthesis, under salt stress. These findings suggest that the OsMPT3 gene modulates phosphate transport and energy supply for ATP synthesis and triggers changes in accumulation of ions and metabolites participating in osmotic regulation in rice under salt stress, thus increasing rice salt tolerance. This study demonstrates the effective application of CRISPR/Cas9 gene-editing to the investigation of plant functional genes.
基金supported by the Fostering Foundation for the Excellent Ph D.Dissertation of Gansu Agricultural University(2013002)the National High Technology Research and Development Program of China(2013AA102505)the Ministry of Science and Technology National Key R&D project(2016YFC0904600)
文摘In the present study, we used a proteomics approach based on a two-dimensional electrophoresis (2-DE) reference map to investigate protein expression in the ovarian tissues of pubertal Swiss-Webster mice subjected to carbon ion radiation (CIR). Among the identified proteins, ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) is associated with the cell cycle[1] and that it influences proliferation in ovarian tissues. We analyzed the expression of UCH-L1 and the proliferation marker proliferation cell nuclear antigen (PCNA) following CIR using immunoblotting and immunofluorescence. The proteomics and biochemical results provide insight into the underlying mechanisms of CIR toxicity in ovarian tissues.
文摘This is the fifth year since the first "Chinese Enterprises Competitiveness Annual Meeting" convened in 2003. During those five years,we have witnessed a period of remarkable performance by Chinese enterprises. These last five years have seen a reaping of the fruits brought about by China's three-decade-long reform and opening, as evidenced by the increasing growth and maturity of Chinese enterprises and the rising competitiveness of publicly listed Chinese enterprises. Along with the development of globalization initiatives, Chinese enterprises are moving firmly and solidly towards internationalization and have begun to have a profound impact on the world economy. The roadmap of Chinese enterprises has now become a focus of global attention.
文摘An international consortium of scientists studying gamma-ray bursts (GRBs) as part of the POLAR (GRB polarimeter) experiment has revealed that high-energy photon emissions from black holes are neither completely chaotic nor completely organized, but a mixture.
文摘The year 2001 saw theconvocation of theFourth National Confer-ence on Work in Tibet.From August to October 2001,we conducted an extensiveinvestigation and study in theurban and rural areas Wewere especially impressed bythe urban expansion in Lhasa,Xigaze and Nyingchi
文摘The advances and retreats of glaciations through the Pleistocene,especially most recent the Last Glacial Maximum(19-26 thousand years ago),have significantly affected the demographic history,abundance and distribution pattern of modern species.During these glaciations,many species were excluded from large parts of their ranges and forced into refugia by the expanding ice sheets,followed by
基金financially supported by National Natural Science Foundation of China (No. 31471899)the Knowledge Innovation Project of the Chinese Academy of Sciences (No. Y455421Z02)
文摘Sacred lotus(Nelumbo nucifera or lotus) is an important aquatic plant in horticulture and ecosystems. As a foundation for exploring genomic variation and evolution among different germplasms, we re-sequenced 19 individuals from three cultivated temperate lotus subgroups(rhizome,seed and flower lotus), one wild temperate lotus subgroup(wild lotus), one tropical lotus group(Thai lotus) and an outgroup(Nelumbo lutea). Through genetic diversity and polymorphism analysis by non-missing SNP sites widely distributed in the whole genome, we confirmed that wild and Thai lotus exhibited greater differentiation with a higher genomic diversity compared to cultivated lotus. Rhizome lotus had the lowest genomic diversity and a closer relationship to wild lotus, whereas the genomes of seed and flower lotus were admixed. Genes in energy metabolism process and plant immunity evolved rapidly in lotus, reflecting local adaptation.We established that candidate genes in genomic regions with significant differentiation associated with temperate and tropical lotus divergence always exhibited highly divergent expression pattern. Together, this study comprehensive and credible interpretates important patterns of genetic diversity and relationships, gene evolution, and genomic signature from ecotypic differentiation of sacred lotus.
文摘Dear Editor :The sustainable cultivation of rice, which serves as staple food crop for more than half of the world's population, is under serious threat due to the huge yield losses inflicted by rice blast disease caused by the globally destructive fungus Magnaporthe oryzae (Pyricularia oryzae) (Dean et al., 2012; Nalley et al., 2016; Deng et al., 2017). This filamentous ascomycete fungus is also capable of causing blast infection on other economically important cereal crops, including wheat, millet, and barley, making it the world's most important plant pathogenic fungus (Zhong et al., 2016).
文摘Subject Code:C18 With the support by the National Natural Science Foundation of China,a collaborative study by the research groups led by Prof.Shen Jianzhong(沈建忠)from the College of Veterinary Medicine,China Agricultural University and Prof.Timothy R.Walsh from Cardiff University demonstrates the
基金funding from the Thousand Youth Talents Program and Institute of Botany,CAS,China
文摘Plants, as primary producers, have been playing an indispensable role in other organisms’ survival and the balance of whole ecosystem on Earth. Especially, they provide the main source of energy, food, and medicine for human beings, some of which are derived from the primary or secondary metabolites
文摘Embryonic stem (ES) cells are under precise control of both intrinsic self-renewal gene regulatory network and extrinsic growth factor-triggered signaling cascades.
文摘LepA, the highly conserved translational GTPase (trGTPase), triggers one-codon back-movement of the elongating ribosome. Here we identify a new enzymatic activity
文摘Subject Code:C05With the support by the National Natural Science Foundation of China,a team of scientists let by Profs.Wu Beili(吴蓓丽),Wang Mingwei and Jiang Hualiang from Shanghai Institute of Materia Medica,Chinese Academy of Sciences has determined the high-resolution atomic structure of a full-length class B
文摘With the support by the National Natural Science Foundation of China and the Chinese Academy of Sciences,the research team led by Prof.Li Junbai(李峻柏)at the CAS Key Lab of Colloid,Interface and Thermodynamics,Institute of Chemistry,Chinese Academy of Sciences,revealed the distribution of proteins in the transformation of inorganic/protein hybrid crystals by super-resolution microscopy,which
基金supported by the National Natural Science Foundation of China(Grants 21973110 and 21925406).
文摘Recently,Gary et al.published an article elucidating how sugars contribute to the protection of dry protein structure.They utilized an ingenious liquid-observed vapor exchange(LOVE)nuclear magnetic resonance(NMR)method,providing valuable insights into the protection mechanism of sugars during the drying process.The details of their study can be found in the article available at https://doi.org/10.1021/acs.biochem.2c00692.
基金supported by the National Natural Science Foundation of China(42471309)the National Key Research and Development Program of China(2020YFA0608504).
文摘The economic potential induced by environmental changes in the Arctic region garnered substantial interest,which positions Arctic trade as a crucial indicator in forecasting the impacts of climate change on the global economy.Nevertheless,attention devoted to the evolving dynamics of trade in the Arctic region remains scarce.In this study,we constructed export trade network in the Arctic region(including Denmark,Finland,Sweden,Norway,Iceland,the Canadian Arctic,the Russian Arctic,Alaska State of the USA,and Greenland)from 1990 to 2019 and analyzed its topology and evolutionary characteristics through complex network theory.We used a structural entropy index based on the distribution of the number of trading partners and the degree of trade concentration to assess export diversity,while we also utilized a revealed comparative advantage index to evaluate product export competitiveness using the share of trade volume of each type of product.The results indicate that the total export trade in the Arctic region increased by 53.4%during 1990-2019,with the most significant growth observed in the exports of chemical products and mineral fuels.The increasing complexity of trade network in the Arctic region resulted in the region’s export destinations no longer being concentrated on a few major countries and regions.The proportion of exports from the Arctic region to Europe decreased by 13.5%,while the proportion of exports from the Arctic region to Asia and North America increased by 6.8%and 3.1%,respectively.The Arctic region exhibited clear distinctions in the range of flows of different products,and its export trade was becoming increasingly diversified.Although differences in comparative advantages between products within individual countries or regions have narrowed,substantial gaps persist.The findings of this study can enhance the comprehensive understanding of the significance and function of Arctic trade activities within the global economy,providing a scientific basis for addressing the associated challenges and opportunities in the context of climate change.
文摘1 In the midst of a stormy night in North Carolina,where rain was pouring down on tin roofs and darkness enveloped the world,an inspiring tale unfolded.Despite the tempests rage,a homeless man appeared as an unsung hero,revealing the depth of the human spirit and the profound connection between the man and his furry(毛茸茸的)companions.