Nestedness is one of the important patterns in island biogeography,community ecology and conservation biology.However,most previous nestedness studies focus on the taxonomic dimension while neglecting the functional a...Nestedness is one of the important patterns in island biogeography,community ecology and conservation biology.However,most previous nestedness studies focus on the taxonomic dimension while neglecting the functional and phylogenetic processes in generating nestedness.Moreover,few studies have examined the seasonal change of the nestedness and underlying processes.Here,we examined the seasonal nestedness of bird assemblages in taxonomic,functional,and phylogenetic dimensions,and determined the underlying processes of nestedness patterns in the Zhoushan Archipelago,China.We surveyed the occurrence, abundance,and habitats of birds on 40 islands.We calculated taxonomic,functional,and phylogenetic nestedness using WNODF and treeNODF.We determined the processes underlying nestedness by relating nestedness ranks to island characteristics and species traits.The WNODF analyses showed that bird assemblages in winter and summer were both significantly nested.The habitat-by-site matrix was also significantly nested.The nestedness of bird assemblages was significantly correlated with island area,habitat diversity,habitat specificity,minimum area requirement,habitat specificity and hand-wing index(HWI) of birds in both seasons.While the distance to the nearest mainland(DTM) exerted the influence on nestedness in summer,the distance to the nearest larger island(DTNL)affected nestedness only in winter.However,the nestedness of bird assemblages was not caused by passive sampling or human disturbance.The results of treeNODF analyses illustrated that bird assemblages were functionally and phylogenetically nested in summer and winter,but the exact mechanisms were somewhat different in these two seasons.Overall,our results supported the habitat nestedness hypothesis,selective extinction hypothesis,and selective colonization hypothesis in both seasons.From a conservation viewpoint,we should protect islands with large area and diverse habitats,islands close to the mainland,and species with large area requirement and high habitat specificity to prevent local extinction.展开更多
Urbanization is one of the most extreme forms of land-use alteration that is advancing across the world with unprecedented speed.As the largest developing country,China has developed a unique path through its high spe...Urbanization is one of the most extreme forms of land-use alteration that is advancing across the world with unprecedented speed.As the largest developing country,China has developed a unique path through its high speed and large scale of urbanization,offering valuable research opportunities for avian ecology.However,a comprehensive review on how birds respond to urbanization in China is still lacking.Here,we systematically reviewed 274 studies published from 1962 to 2024 to determine the research trends,current insights,and future directions of avian response to urbanization in China.We synthesized research trends across four core avian response dimensions to urbanization—diversity,behavior,physiology,and life-history—and their applications in conservation strategy design.The number of publications in avian response to urbanization in China increased annually,and it is influenced by China's developing policies of urbanization.The results also showed an unbalanced geographical pattern of the publications,as the research preferences are relatively prevalent in the developed areas of eastern China.In contrast,there are insufficient studies in the emerging urbanizing areas in the western and northeastern China.Regarding the research contents,most existing studies are focusing on the patterns of bird diversity,while there are few studies on the underlying mechanisms,such as physiological adjustments and life-history strategies.In addition,passerines are the most frequent ones among the studied species.Integrating multidimensional urbanization indices and citizen science data are gradually becoming a new trend in recent years.Our study emphasizes that future studies should pay more attention to the response mechanism of birds in urbanizing processes,multidimensional and interdisciplinary studies,and the transformation of the research results into conservation practices.展开更多
The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic ...The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic diversity,with relatively less research on functional and phylogenetic diversity.In this study,we examined the phylogenetic and functional diversity and underlying influencing factors of bird communities in 37 urban parks in Nanjing,China.We conducted a systematic survey of bird communities in Nanjing urban parks and selected six park characteristics that are generally considered to affect bird diversity.Model selection based on corrected Akaike Information Criterion(AICc)and model averaging showed that park area,habitat diversity and building index(a proxy for the degree of urbanization)were significant factors affecting avian phylogenetic and functional diversity in Nanjing urban parks.Specifically,habitat diversity and park area were positively correlated with bird diversity,while the building index was negatively correlated with bird diversity.Moreover,the phylogenetic and functional structures of urban bird communities exhibited a clustered pattern,indicating that environmental filtering might play a role in shaping community composition.In addition,building index had certain impact on the construction of bird phylogenetic communities in urban parks.Our results suggest that expanding park areas,increasing habitat diversity and reducing building indexes may be effective measures to increase the avian phylogenetic and functional diversity in our system.展开更多
Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their ...Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their diversity in urban wetlands reflects the response of wildlife to urbanization.However,very few studies have investigated seasonal differences in the multidimensional diversity of waterbirds in urbanized landscapes.In this study,we analyzed various wetland parameters that could potentially affect the seasonal variations in multidimensional diversity of waterbirds in Nanjing,China.We surveyed waterbirds in 29 urban wetlands using the point count method during breeding and non-breeding seasons from November 2022 to June 2023.We then employed multiple linear regressions and information-theoretic approaches to investigate the impact of wetland characteristics on waterbird diversity.We found that water body area and buffer zone connectivity consistently emerged as positive factors affecting waterbird taxonomic and phylogenetic diversity across seasons.Conversely,the urbanization synthetic index was negatively correlated with waterbird diversity only during the breeding season.Regarding functional diversity,we found that the positive correlation between buffer zone connectivity and waterbird diversity was specific to the breeding season.Therefore,for effective conservation of waterbird diversity in our system,wetland planning should prioritize expanding wetland water body areas,enhancing wetland connectivity,minimizing human disturbance during the breeding season,and implementing ecological restoration measures in urbanized wetlands to mitigate adverse effects of urbanization.展开更多
Leaf-color mutants have proven valuable for studying chlorophyll metabolism,photosynthesis,and yield improvement.In this study,we identified a yellow-leaf(yl)mutant in soybean(Glycine max),characterized by reduced chl...Leaf-color mutants have proven valuable for studying chlorophyll metabolism,photosynthesis,and yield improvement.In this study,we identified a yellow-leaf(yl)mutant in soybean(Glycine max),characterized by reduced chlorophyll accumulation,lower net photosynthesis rate,and fewer grain number per plant than the wild type.To identify genes associated with chlorophyll content,we performed a largescale linkage mapping study using recombinant inbred lines from a cross between the yl mutant and a green-leaf cultivar across three environments.Using quantitative trait locus sequencing(QTL-seq)analysis,we mapped 12 QTL to chromosomes 5,13,15,19,and 20.Of these QTL,one new dominant locus with the largest LOD,named qCC1,was identified consistently and explained 31.73% of the total phenotypic variation on average.Notably,qCC1 was also associated with yield-related traits,including plant height and pod number per plant.Fine-mapping narrowed down qCC1 to an 82.29-kb region.Within this interval,we identified Glyma.15 g087500.1,encoding an ankyrin repeat-containing protein,as the most likely candidate gene,because its homologs are reported to function in thylakoid membrane biogenesis during plastid development.Phenotypic analysis of near-isogenic lines(NILs)revealed that those harboring the qCC1 allele conferring green leaves displayed significantly enhanced chlorophyll content by 136.53%-323.92%,net photosynthesis rate by 11.64%-42.13%,and yield by 111.32% compared with NILs carrying the allele conferring yellow leaves.Comparative transcriptome profiling of NILs coupled with RT-qPCR validation demonstrated that qCC1 up-regulated one differentially expressed gene(DEG)associated with chlorophyll biosynthesis and six DEGs related to photosystem,whereas it downregulated one gene involved in chlorophyll degradation.These findings provide valuable insights into the biological function and regulatory mechanism of chlorophyll metabolism and offer guidance for breeding soybean varieties with enhanced photosynthetic efficiency and high yield.展开更多
The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this st...The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this study,we established an optically stimulated luminescence chronology for the QSHA profile in the Yili Basin,a region influenced by westerlies.Grain size and trace element data were used as paleoclimatic indicators.We investigated the relationships among Central Asian dust activity,humidity,and westerlies strength on orbital to millennial scale from 37.4 ka to 11.6 ka.Our study reveals that,on orbital timescales,humidity is positively correlated with westerlies strength which controlled by precession.Dust activity is controlled by Siberian High which was regulated by Northern Hemisphere high-latitude temperature.Their responses to low-latitude and high-latitude forcing mechanisms respectively and present an opposite relationship.On millennial timescales,humidity and westerlies strength are positively correlated.During Marine Isotope Stage(MIS)2,humidity and dust activity show synchronous fluctuations,while during MIS 3,they exhibit an inverse relationship.Westerlies strength regulated humidity,which subsequently controlled glacial activity in the Tianshan Mountains,influencing dust activity in Central Asia.Additionally,the QSHA profile recorded seven Dansgaard-Oeschger(D-O)events on millennial timescales,indicating a potential link between Central Asian dust activity and high-latitude temperature variations in the Northern Hemisphere.Our findings provide new insights into dust and humidity interaction during the last glaciation periods in Central Asia and contribute to understanding global dust and hydrological cycles.展开更多
Peat soil is a loose,moisture-rich organic matter accumulation formed by the deposition of plants in swamps and lakes after their death.It is characterized by high moisture content,large void ratio,high compressibilit...Peat soil is a loose,moisture-rich organic matter accumulation formed by the deposition of plants in swamps and lakes after their death.It is characterized by high moisture content,large void ratio,high compressibility,and strong rheological properties.These characteristics result in a complex consolidation process.A systematic understanding of the consolidation mechanism of peat soil is essential for elucidating its consolidation behavior.Previous studies have failed to provide consistent information on the microscopic morphology of peat soil.Moreover,quantitative studies on pore structure changes during peat soil consolidation remain lacking.To resolve these research gaps,the microscopic morphology and pore types of peat,highly organic peaty soil,and medium organic peaty soil from certain regions of Yunnan province,China,were observed and analyzed using scanning electron microscopy.Additionally,quantitative research on pore structure changes during peat soil consolidation was conducted.The results show that the humic acid in peat soil of Yunnan province has no pores,and there is no pore between humic acid and clay minerals.There are three typical pore structures,and the three typical pores were quantitatively analyzed.During consolidation,the consolidation deformation of peat soil is primarily caused by the internal pore compression of plant residues and pores between plant residues.At the same time,the revelation of the differentiated influence mechanism of load levels on the compression of inter/intra-plant residue pores.The decrease in the proportion of pores between plant residues first increased and then decreased with an increase in load,reaching a peak between 100-200 kPa.The decrease in pores inside the plant residues increased with an increasing load.Additionally,pore compression between the plant residues under different load levels primarily caused the compression deformation of Dali peat during the primary consolidation stage.By contrast,the pore compression inside the plant residues primarily caused the compression deformation during the secondary consolidation stage.展开更多
A geomagnetic field is a significant factor dur-ing the growth and development of trees.Changes in the magnetic field(MF)will result in reactions at the biochemi-cal,molecular,cellular and gene levels.However,it is no...A geomagnetic field is a significant factor dur-ing the growth and development of trees.Changes in the magnetic field(MF)will result in reactions at the biochemi-cal,molecular,cellular and gene levels.However,it is not clear how a magnetic field affects metabolism and home-ostasis under stressful conditions such as salinity.In this study,a novel method was developed of a static magnetic field(SMF)to investigate magnetobiological changes in trees.The results show that pre-treatment of poplar(Popu-lus×euramericana‘Neva’)cuttings with a static magnetic field significantly mitigated the negative effects of salinity stress on their growth and physiological activities.Bio-chemical assays revealed that several chemical messengers,including hydrogen peroxide(H2O2)and O_(2)^(·-),were sig-nificantly improved in roots treated with salt,implying an increase reactive oxygen species.A static magnetic field also significantly increased proline concentrations,soluble protein contents,and CAT and SOD activities.Electrophysiological experiments further revealed that pre-treatment with a static magnetic field remarkably decreased salt-induced Na^(+)influx and H^(+)efflux which control plant salt tolerance.In pharmacological experiments,because the Na^(+)/H^(+)cor-relation was closely related to the SMF-activated plasma membrane and Na^(+)antiporter activity alleviated the mas-sive accumulation of salt-induced reactive oxygen spe-cies(ROS)within the roots.In addition,a static magnetic field dramatically increased the transcriptional activity of stress-responsive genes,including PtrRBOHD and PtrHA5.Together,these results indicate that SMF reduced Na^(+)influx by activating Na^(+)/H^(+)antiporters and plasma membrane H^(+)-ATPase to effectively maintain homeostasis by regu-lating the reactive oxygen species system and cytoplasmic osmotic potential.Ultimately,these static magnetic field methods improved salt tolerance in poplar cuttings,and,for future research,similar methods could be applied to other plants.展开更多
Chronic kidney disease(CKD)is one kind of illness with abnormal renal structure and function caused by many factors.Probiotics can be used to regulate intestinal microflora and enhance intestinal mucosal barrier,thus,...Chronic kidney disease(CKD)is one kind of illness with abnormal renal structure and function caused by many factors.Probiotics can be used to regulate intestinal microflora and enhance intestinal mucosal barrier,thus,intervention with probiotics may be regarded as one of the potential ways to protect against CKD.In vitro and in vivo experiments showed that Lactiplantibacillus plantarum MA2(MA2),a probiotic separated from traditional Chinese Tibetan kefir grains,could degrade the uremic toxins including creatinine,urea nitrogen and uric acid.Oral administration of MA2 or its inactive strains(IMA2)could decrease serum uremic toxins of adenine-induced CKD mice,and also elevate the relative expression of claudin-1.Meanwhile,intervention of MA2 or IMA2 decreased the contents of lipopolysaccharide,Toll-like receptor 4(TLR4)and interleukin-1β(IL-1β)in the kidney.16S rDNA sequencing results indicated that the intervention of MA2 or IMA2 regulated the gut microbiota structure by elevating the abundance of Lactobacillus,and decreasing the abundance of Proteobacteria.Thus,oral administration of MA2 or IMA2 can reduce the uremic toxins in CKD mice by regulating gut microflora and restoring the intestinal mucosal barrier.Our study provided a theoretical basis for the application of MA2 and its postbiotics in the CKD intervention and treatment.展开更多
Nestedness is an important pattern frequently reported for species assemblages on islands or fragmented systems.However,to date,there are few studies that comprehensively investigated faunal nestedness and underlying ...Nestedness is an important pattern frequently reported for species assemblages on islands or fragmented systems.However,to date,there are few studies that comprehensively investigated faunal nestedness and underlying processes in urbanized landscapes.In this study,we examined the nestedness of bird assemblages and its underlying causal mechanisms in 37 urban parks in Nanjing,China.We used the line-transect method to survey birds from April 2019 to January 2020.We used the Weighted Nestedness metric based on Overlap and Decreasing Fill(WNODF)to estimate the nestedness of bird assemblages.We applied spearman partial correlation test to examine the relationships between nestedness ranks of sites and park characteristics(area,isolation,anthropogenic noise,number of habitat types,and building index),as well as between nestedness ranks of species and their ecological traits(body size,geographic range size,clutch size,minimum area requirement,dispersal ratio,and habitat specificity).We found that bird assemblages in urban parks were significantly nested.Park area,habitat diversity,building index,habitat specificity,and minimum area requirement of birds were significantly correlated with nestedness.Therefore,the nestedness of bird assemblages was caused by selective extinction,habitat nestedness,and urbanization.However,the nestedness of bird assemblages did not result from passive sampling,selective colonization,or human disturbance.Overall,to maximize the number of species preserved in our system,conservation priority should be given to parks with large area,rich habitat diversity,and less building index.From a species perspective,we should focus on species with large area requirement and high habitat specificity for their effective conservation.展开更多
Abstract Nestedness is a pattern frequently reported for faunal assemblages in fragmented systems. Although nestedness has been documented for a wide range of taxa, it is rarely tested in snake assemblages. To arrive ...Abstract Nestedness is a pattern frequently reported for faunal assemblages in fragmented systems. Although nestedness has been documented for a wide range of taxa, it is rarely tested in snake assemblages. To arrive at robust generalizations about processes and mechanisms structuring island biotas, it is important to examine under-represented taxa such as snakes for the insights they may offer. We tested for the existence of nestedness and underlying causal mechanisms using snake data collected on islands in the Thousand Island Lake, China. We used the line-transect method to survey snake occupancy and abundance on 20 islands during two breeding seasons in 2009 and 2010. We used the recently developed metric WNODF to estimate nestedness. We used Spearman rank correlations to examine the associations of nestedness and habitat variables (area, isolation, and habitat diversity) as well as life-history traits (body size, clutch size, geographical range size and area requirement) related to species extinction and immigration tendencies. Snake assemblages were significantly nested and were shaped by extinction processes mediated through area effects and habitat nestedness. The nestedness of snake assemblages was not due to passive sampling or selective colonization. From a conservation viewpoint, our results indicate that we should protect both the largest island with the most species-rich community and habitat-rich islands to maximize the number of species preserved .展开更多
OBJECTIVE: To compare the efficacy of an acu- puncture regimen for persistent allergic rhinitis (PER), aimed at improving a patient's mind or Shen in Traditional Chinese Medicine, to that of a sec- ond-generation ...OBJECTIVE: To compare the efficacy of an acu- puncture regimen for persistent allergic rhinitis (PER), aimed at improving a patient's mind or Shen in Traditional Chinese Medicine, to that of a sec- ond-generation H-receptor antagonist, cetirizine hydrochloride. METHODS: This multicenter, randomized, con- trolled clinical trial on PER will be conducted at three institutions in China. The total study period will be 9 weeks. After a 1-week preparatory screen- ing period, 240 eligible participants with PER willbe randomized to receive acupuncture or pharma- cotherapy (1: 1) for 4 weeks with a 4-week fol- low-up. The primary outcome will be changes in 7-day average total nasal symptom score. Second- ary outcome measures include rhinoconjunctivitis quality of life questionnaire score and total non-na- sal symptom score. RESULTS: The presence and seriousness of psycho- logical and emotional impairments should be con- sidered in therapeutic programs for allergic rhinitis. No clinical trial for treating allergic rhinitis via acu- puncture regulation of psychological and emotion- al activities has been reported. CONCLUSION: The findings of the trial will allow us to determine the effects of the mind (Shen)-regula- tion treatment approach. We will also be able to confirm if the effects of acupuncture are equivalent to those of the conventional drug cetirizine hydro- chloride.展开更多
基金supported by the National Natural Science Foundation of China (32271734)。
文摘Nestedness is one of the important patterns in island biogeography,community ecology and conservation biology.However,most previous nestedness studies focus on the taxonomic dimension while neglecting the functional and phylogenetic processes in generating nestedness.Moreover,few studies have examined the seasonal change of the nestedness and underlying processes.Here,we examined the seasonal nestedness of bird assemblages in taxonomic,functional,and phylogenetic dimensions,and determined the underlying processes of nestedness patterns in the Zhoushan Archipelago,China.We surveyed the occurrence, abundance,and habitats of birds on 40 islands.We calculated taxonomic,functional,and phylogenetic nestedness using WNODF and treeNODF.We determined the processes underlying nestedness by relating nestedness ranks to island characteristics and species traits.The WNODF analyses showed that bird assemblages in winter and summer were both significantly nested.The habitat-by-site matrix was also significantly nested.The nestedness of bird assemblages was significantly correlated with island area,habitat diversity,habitat specificity,minimum area requirement,habitat specificity and hand-wing index(HWI) of birds in both seasons.While the distance to the nearest mainland(DTM) exerted the influence on nestedness in summer,the distance to the nearest larger island(DTNL)affected nestedness only in winter.However,the nestedness of bird assemblages was not caused by passive sampling or human disturbance.The results of treeNODF analyses illustrated that bird assemblages were functionally and phylogenetically nested in summer and winter,but the exact mechanisms were somewhat different in these two seasons.Overall,our results supported the habitat nestedness hypothesis,selective extinction hypothesis,and selective colonization hypothesis in both seasons.From a conservation viewpoint,we should protect islands with large area and diverse habitats,islands close to the mainland,and species with large area requirement and high habitat specificity to prevent local extinction.
基金supported by the National Natural Science Foundation of China(No.32271743)。
文摘Urbanization is one of the most extreme forms of land-use alteration that is advancing across the world with unprecedented speed.As the largest developing country,China has developed a unique path through its high speed and large scale of urbanization,offering valuable research opportunities for avian ecology.However,a comprehensive review on how birds respond to urbanization in China is still lacking.Here,we systematically reviewed 274 studies published from 1962 to 2024 to determine the research trends,current insights,and future directions of avian response to urbanization in China.We synthesized research trends across four core avian response dimensions to urbanization—diversity,behavior,physiology,and life-history—and their applications in conservation strategy design.The number of publications in avian response to urbanization in China increased annually,and it is influenced by China's developing policies of urbanization.The results also showed an unbalanced geographical pattern of the publications,as the research preferences are relatively prevalent in the developed areas of eastern China.In contrast,there are insufficient studies in the emerging urbanizing areas in the western and northeastern China.Regarding the research contents,most existing studies are focusing on the patterns of bird diversity,while there are few studies on the underlying mechanisms,such as physiological adjustments and life-history strategies.In addition,passerines are the most frequent ones among the studied species.Integrating multidimensional urbanization indices and citizen science data are gradually becoming a new trend in recent years.Our study emphasizes that future studies should pay more attention to the response mechanism of birds in urbanizing processes,multidimensional and interdisciplinary studies,and the transformation of the research results into conservation practices.
基金supported by the National Natural Science Foundation of China(No.32271734)。
文摘The acceleration of global urbanization has caused habitat loss,fragmentation,and decrease of habitat quality,often leading to a decline in biodiversity.However,most previous urbanization studies focused on taxonomic diversity,with relatively less research on functional and phylogenetic diversity.In this study,we examined the phylogenetic and functional diversity and underlying influencing factors of bird communities in 37 urban parks in Nanjing,China.We conducted a systematic survey of bird communities in Nanjing urban parks and selected six park characteristics that are generally considered to affect bird diversity.Model selection based on corrected Akaike Information Criterion(AICc)and model averaging showed that park area,habitat diversity and building index(a proxy for the degree of urbanization)were significant factors affecting avian phylogenetic and functional diversity in Nanjing urban parks.Specifically,habitat diversity and park area were positively correlated with bird diversity,while the building index was negatively correlated with bird diversity.Moreover,the phylogenetic and functional structures of urban bird communities exhibited a clustered pattern,indicating that environmental filtering might play a role in shaping community composition.In addition,building index had certain impact on the construction of bird phylogenetic communities in urban parks.Our results suggest that expanding park areas,increasing habitat diversity and reducing building indexes may be effective measures to increase the avian phylogenetic and functional diversity in our system.
基金supported by the National Natural Science Foundation of China(32271743).
文摘Urban wetlands are considered as"habitat islands"within the urban matrix that contribute to species conservation.Waterbirds are sensitive pollution indicators in terrestrial and aquatic ecosystems,and their diversity in urban wetlands reflects the response of wildlife to urbanization.However,very few studies have investigated seasonal differences in the multidimensional diversity of waterbirds in urbanized landscapes.In this study,we analyzed various wetland parameters that could potentially affect the seasonal variations in multidimensional diversity of waterbirds in Nanjing,China.We surveyed waterbirds in 29 urban wetlands using the point count method during breeding and non-breeding seasons from November 2022 to June 2023.We then employed multiple linear regressions and information-theoretic approaches to investigate the impact of wetland characteristics on waterbird diversity.We found that water body area and buffer zone connectivity consistently emerged as positive factors affecting waterbird taxonomic and phylogenetic diversity across seasons.Conversely,the urbanization synthetic index was negatively correlated with waterbird diversity only during the breeding season.Regarding functional diversity,we found that the positive correlation between buffer zone connectivity and waterbird diversity was specific to the breeding season.Therefore,for effective conservation of waterbird diversity in our system,wetland planning should prioritize expanding wetland water body areas,enhancing wetland connectivity,minimizing human disturbance during the breeding season,and implementing ecological restoration measures in urbanized wetlands to mitigate adverse effects of urbanization.
基金supported by the Heilongjiang Provincial Natural Science Foundation of China(SS2023C002)。
文摘Leaf-color mutants have proven valuable for studying chlorophyll metabolism,photosynthesis,and yield improvement.In this study,we identified a yellow-leaf(yl)mutant in soybean(Glycine max),characterized by reduced chlorophyll accumulation,lower net photosynthesis rate,and fewer grain number per plant than the wild type.To identify genes associated with chlorophyll content,we performed a largescale linkage mapping study using recombinant inbred lines from a cross between the yl mutant and a green-leaf cultivar across three environments.Using quantitative trait locus sequencing(QTL-seq)analysis,we mapped 12 QTL to chromosomes 5,13,15,19,and 20.Of these QTL,one new dominant locus with the largest LOD,named qCC1,was identified consistently and explained 31.73% of the total phenotypic variation on average.Notably,qCC1 was also associated with yield-related traits,including plant height and pod number per plant.Fine-mapping narrowed down qCC1 to an 82.29-kb region.Within this interval,we identified Glyma.15 g087500.1,encoding an ankyrin repeat-containing protein,as the most likely candidate gene,because its homologs are reported to function in thylakoid membrane biogenesis during plastid development.Phenotypic analysis of near-isogenic lines(NILs)revealed that those harboring the qCC1 allele conferring green leaves displayed significantly enhanced chlorophyll content by 136.53%-323.92%,net photosynthesis rate by 11.64%-42.13%,and yield by 111.32% compared with NILs carrying the allele conferring yellow leaves.Comparative transcriptome profiling of NILs coupled with RT-qPCR validation demonstrated that qCC1 up-regulated one differentially expressed gene(DEG)associated with chlorophyll biosynthesis and six DEGs related to photosystem,whereas it downregulated one gene involved in chlorophyll degradation.These findings provide valuable insights into the biological function and regulatory mechanism of chlorophyll metabolism and offer guidance for breeding soybean varieties with enhanced photosynthetic efficiency and high yield.
基金supported by the Natural Science Foundation of China(Grant Nos.42372220,42172207)the Youth Innovation Promotion Association Chinese Academy of Sciences(Grant No.Y2022102)+1 种基金the Science and Technology Innovation Project of Laoshan Laboratory(Grant No.LSKJ202203300)the International Partnership Program of the Chinese Academy of Sciences.
文摘The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this study,we established an optically stimulated luminescence chronology for the QSHA profile in the Yili Basin,a region influenced by westerlies.Grain size and trace element data were used as paleoclimatic indicators.We investigated the relationships among Central Asian dust activity,humidity,and westerlies strength on orbital to millennial scale from 37.4 ka to 11.6 ka.Our study reveals that,on orbital timescales,humidity is positively correlated with westerlies strength which controlled by precession.Dust activity is controlled by Siberian High which was regulated by Northern Hemisphere high-latitude temperature.Their responses to low-latitude and high-latitude forcing mechanisms respectively and present an opposite relationship.On millennial timescales,humidity and westerlies strength are positively correlated.During Marine Isotope Stage(MIS)2,humidity and dust activity show synchronous fluctuations,while during MIS 3,they exhibit an inverse relationship.Westerlies strength regulated humidity,which subsequently controlled glacial activity in the Tianshan Mountains,influencing dust activity in Central Asia.Additionally,the QSHA profile recorded seven Dansgaard-Oeschger(D-O)events on millennial timescales,indicating a potential link between Central Asian dust activity and high-latitude temperature variations in the Northern Hemisphere.Our findings provide new insights into dust and humidity interaction during the last glaciation periods in Central Asia and contribute to understanding global dust and hydrological cycles.
基金supported by the Fundamental Research Funds for the Central Universities(2025JBZY019)the Funding of Key Research and Development Project of CCCC(2021-ZJKJ-18).
文摘Peat soil is a loose,moisture-rich organic matter accumulation formed by the deposition of plants in swamps and lakes after their death.It is characterized by high moisture content,large void ratio,high compressibility,and strong rheological properties.These characteristics result in a complex consolidation process.A systematic understanding of the consolidation mechanism of peat soil is essential for elucidating its consolidation behavior.Previous studies have failed to provide consistent information on the microscopic morphology of peat soil.Moreover,quantitative studies on pore structure changes during peat soil consolidation remain lacking.To resolve these research gaps,the microscopic morphology and pore types of peat,highly organic peaty soil,and medium organic peaty soil from certain regions of Yunnan province,China,were observed and analyzed using scanning electron microscopy.Additionally,quantitative research on pore structure changes during peat soil consolidation was conducted.The results show that the humic acid in peat soil of Yunnan province has no pores,and there is no pore between humic acid and clay minerals.There are three typical pore structures,and the three typical pores were quantitatively analyzed.During consolidation,the consolidation deformation of peat soil is primarily caused by the internal pore compression of plant residues and pores between plant residues.At the same time,the revelation of the differentiated influence mechanism of load levels on the compression of inter/intra-plant residue pores.The decrease in the proportion of pores between plant residues first increased and then decreased with an increase in load,reaching a peak between 100-200 kPa.The decrease in pores inside the plant residues increased with an increasing load.Additionally,pore compression between the plant residues under different load levels primarily caused the compression deformation of Dali peat during the primary consolidation stage.By contrast,the pore compression inside the plant residues primarily caused the compression deformation during the secondary consolidation stage.
基金supported by the the National Natural Science Foundation of China(32071751).
文摘A geomagnetic field is a significant factor dur-ing the growth and development of trees.Changes in the magnetic field(MF)will result in reactions at the biochemi-cal,molecular,cellular and gene levels.However,it is not clear how a magnetic field affects metabolism and home-ostasis under stressful conditions such as salinity.In this study,a novel method was developed of a static magnetic field(SMF)to investigate magnetobiological changes in trees.The results show that pre-treatment of poplar(Popu-lus×euramericana‘Neva’)cuttings with a static magnetic field significantly mitigated the negative effects of salinity stress on their growth and physiological activities.Bio-chemical assays revealed that several chemical messengers,including hydrogen peroxide(H2O2)and O_(2)^(·-),were sig-nificantly improved in roots treated with salt,implying an increase reactive oxygen species.A static magnetic field also significantly increased proline concentrations,soluble protein contents,and CAT and SOD activities.Electrophysiological experiments further revealed that pre-treatment with a static magnetic field remarkably decreased salt-induced Na^(+)influx and H^(+)efflux which control plant salt tolerance.In pharmacological experiments,because the Na^(+)/H^(+)cor-relation was closely related to the SMF-activated plasma membrane and Na^(+)antiporter activity alleviated the mas-sive accumulation of salt-induced reactive oxygen spe-cies(ROS)within the roots.In addition,a static magnetic field dramatically increased the transcriptional activity of stress-responsive genes,including PtrRBOHD and PtrHA5.Together,these results indicate that SMF reduced Na^(+)influx by activating Na^(+)/H^(+)antiporters and plasma membrane H^(+)-ATPase to effectively maintain homeostasis by regu-lating the reactive oxygen species system and cytoplasmic osmotic potential.Ultimately,these static magnetic field methods improved salt tolerance in poplar cuttings,and,for future research,similar methods could be applied to other plants.
基金financially supported by the National Natural Science Foundation of China(31801514)China Postdoctoral Science Foundation(2020M680895)。
文摘Chronic kidney disease(CKD)is one kind of illness with abnormal renal structure and function caused by many factors.Probiotics can be used to regulate intestinal microflora and enhance intestinal mucosal barrier,thus,intervention with probiotics may be regarded as one of the potential ways to protect against CKD.In vitro and in vivo experiments showed that Lactiplantibacillus plantarum MA2(MA2),a probiotic separated from traditional Chinese Tibetan kefir grains,could degrade the uremic toxins including creatinine,urea nitrogen and uric acid.Oral administration of MA2 or its inactive strains(IMA2)could decrease serum uremic toxins of adenine-induced CKD mice,and also elevate the relative expression of claudin-1.Meanwhile,intervention of MA2 or IMA2 decreased the contents of lipopolysaccharide,Toll-like receptor 4(TLR4)and interleukin-1β(IL-1β)in the kidney.16S rDNA sequencing results indicated that the intervention of MA2 or IMA2 regulated the gut microbiota structure by elevating the abundance of Lactobacillus,and decreasing the abundance of Proteobacteria.Thus,oral administration of MA2 or IMA2 can reduce the uremic toxins in CKD mice by regulating gut microflora and restoring the intestinal mucosal barrier.Our study provided a theoretical basis for the application of MA2 and its postbiotics in the CKD intervention and treatment.
基金Supported by the National Natural Science Foundation of China(31770462 and 31971545)Natural Science Foundation of Zhejiang Province(LZ18C030002).
文摘Nestedness is an important pattern frequently reported for species assemblages on islands or fragmented systems.However,to date,there are few studies that comprehensively investigated faunal nestedness and underlying processes in urbanized landscapes.In this study,we examined the nestedness of bird assemblages and its underlying causal mechanisms in 37 urban parks in Nanjing,China.We used the line-transect method to survey birds from April 2019 to January 2020.We used the Weighted Nestedness metric based on Overlap and Decreasing Fill(WNODF)to estimate the nestedness of bird assemblages.We applied spearman partial correlation test to examine the relationships between nestedness ranks of sites and park characteristics(area,isolation,anthropogenic noise,number of habitat types,and building index),as well as between nestedness ranks of species and their ecological traits(body size,geographic range size,clutch size,minimum area requirement,dispersal ratio,and habitat specificity).We found that bird assemblages in urban parks were significantly nested.Park area,habitat diversity,building index,habitat specificity,and minimum area requirement of birds were significantly correlated with nestedness.Therefore,the nestedness of bird assemblages was caused by selective extinction,habitat nestedness,and urbanization.However,the nestedness of bird assemblages did not result from passive sampling,selective colonization,or human disturbance.Overall,to maximize the number of species preserved in our system,conservation priority should be given to parks with large area,rich habitat diversity,and less building index.From a species perspective,we should focus on species with large area requirement and high habitat specificity for their effective conservation.
基金We thank two anonymous reviewers for helpful comments on earlier version of the manuscript. We are grateful to Chunan Forestry Bureau and the Thousand Island Lake National Forest Park for permits necessary to conduct the research. This study was supported by the National Natural Science Foundation of China (Nos. 31100394, 31170397), the China Postdoctoral Science Foundation (No. 20070411192), Zhejiang Provincial Postdoctoral Science Foundation, and the Fundamental Research Funds for the Central Universities.
文摘Abstract Nestedness is a pattern frequently reported for faunal assemblages in fragmented systems. Although nestedness has been documented for a wide range of taxa, it is rarely tested in snake assemblages. To arrive at robust generalizations about processes and mechanisms structuring island biotas, it is important to examine under-represented taxa such as snakes for the insights they may offer. We tested for the existence of nestedness and underlying causal mechanisms using snake data collected on islands in the Thousand Island Lake, China. We used the line-transect method to survey snake occupancy and abundance on 20 islands during two breeding seasons in 2009 and 2010. We used the recently developed metric WNODF to estimate nestedness. We used Spearman rank correlations to examine the associations of nestedness and habitat variables (area, isolation, and habitat diversity) as well as life-history traits (body size, clutch size, geographical range size and area requirement) related to species extinction and immigration tendencies. Snake assemblages were significantly nested and were shaped by extinction processes mediated through area effects and habitat nestedness. The nestedness of snake assemblages was not due to passive sampling or selective colonization. From a conservation viewpoint, our results indicate that we should protect both the largest island with the most species-rich community and habitat-rich islands to maximize the number of species preserved .
基金Supported by Capital Research on the Clinical Characteristic Application Projects,Beijing Municipal Science & Technology Commission(No.D101100050010022)
文摘OBJECTIVE: To compare the efficacy of an acu- puncture regimen for persistent allergic rhinitis (PER), aimed at improving a patient's mind or Shen in Traditional Chinese Medicine, to that of a sec- ond-generation H-receptor antagonist, cetirizine hydrochloride. METHODS: This multicenter, randomized, con- trolled clinical trial on PER will be conducted at three institutions in China. The total study period will be 9 weeks. After a 1-week preparatory screen- ing period, 240 eligible participants with PER willbe randomized to receive acupuncture or pharma- cotherapy (1: 1) for 4 weeks with a 4-week fol- low-up. The primary outcome will be changes in 7-day average total nasal symptom score. Second- ary outcome measures include rhinoconjunctivitis quality of life questionnaire score and total non-na- sal symptom score. RESULTS: The presence and seriousness of psycho- logical and emotional impairments should be con- sidered in therapeutic programs for allergic rhinitis. No clinical trial for treating allergic rhinitis via acu- puncture regulation of psychological and emotion- al activities has been reported. CONCLUSION: The findings of the trial will allow us to determine the effects of the mind (Shen)-regula- tion treatment approach. We will also be able to confirm if the effects of acupuncture are equivalent to those of the conventional drug cetirizine hydro- chloride.