With the advancement of astronomical observation technology,people have a deeper understanding of the formation and evolution of galaxies,but many details of our own Milky Way and other external galaxies are still unk...With the advancement of astronomical observation technology,people have a deeper understanding of the formation and evolution of galaxies,but many details of our own Milky Way and other external galaxies are still unknown.Therefore,by studying the formation and orbital transformation mechanism of satellites,planets and stars,the author puts forward a new theory on the formation and evolution of stars and galaxies,thus revealing the hierarchical structure of galaxies and the formation and evolution laws of main sequence stars,red giants,white dwarfs,black dwarfs,supernovae,neutron stars,black holes and quasars.Some special phenomena in the course of star formation and evolution,such as sunspots,flares,fast radio bursts and gamma-ray bursts,have also been revealed.展开更多
Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorl...Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorly understood.In this study,we assessed SRBSDV susceptibility in 20 Xian/indica(XI)and 20 Geng/japonica(GJ)rice varieties.XI-1B accessions in the Xian subgroup displayed higher resistance than GJ accessions.Comparative transcriptome analysis revealed changes in processes like oxidoreductase activity,jasmonic acid(JA)metabolism,and stress response.JA sensitivity assays further linked antiviral defense to the JA pathway.These findings highlight a JA-mediated resistance mechanism in rice and offer insights for breeding SRBSDV-resistant varieties.展开更多
Plant height is an important trait that affects the crop yield and overall productivity.The Green Revolution,which began in the 1960s,brought about a remarkable surge in grain production,largely credited to the introd...Plant height is an important trait that affects the crop yield and overall productivity.The Green Revolution,which began in the 1960s,brought about a remarkable surge in grain production,largely credited to the introduction of new wheat(Triticum aestivum)and rice(Oryza sativa)varieties,specifically the dwarf variants.Short plants offer several advantages,including denser planting,resistance to lodging,and easier application of fertilizers or fungicides(Stokstad,2023).展开更多
The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countrie...The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countries.However,the currently planted varieties are all semi-domesticated landraces with delayed flowering and excessive height.These defects limit yield improvement per unit area and mechanized harvesting.In this study,a major QTL associated with flowering time and plant height in adlay has been mapped and identified as Cl CCT,a gene having a conserved function and regulatory pathway for inhibiting flowering time and increasing plant height in gramineous crops.Among the six identified haplotypes of Cl CCT,the haplotype with 38-bp insertion in promoter region of Cl CCT has earlier flowering time and wider geographical distribution than other haplotypes.The insertion variation,which arises from the segmental duplication of Cl CCT,can inhibit the expression level of reporter gene and has been used in breeding for early maturity and dwarfing.These research results not only reinforce our understanding of the importance of CCT domain protein in the tropical crops adapting to high-latitude environment,but also provide a validated breeding target for the early maturity and dwarfing of adlay.展开更多
We present the discovery of TCP J07222683+6220548,a new ultracompact binary system of the AM CVn type.This system was first identified displaying aΔV=7.6 mag outburst on 2025-01-20.9416 UTC by the New Milky Way wide-...We present the discovery of TCP J07222683+6220548,a new ultracompact binary system of the AM CVn type.This system was first identified displaying aΔV=7.6 mag outburst on 2025-01-20.9416 UTC by the New Milky Way wide-field survey for transients and later independently detected by ASAS-SN and ZTF.The outburst peaked at V_(max)=12.45 and lasted for seven days,followed by a series of rebrightenings.No previous outbursts are found in archival data.Positive superhumps with a period of 0.032546±0.000084 day(46.87±0.12 minutes),barely detectable during the main outburst,became clearly visible during the first rebrightening that lasted from day 18 to day 24 after the initial outburst.No convincing change in the superhump period was detected.Dense time-series photometry follow-up by a pair of 0.5 m INASAN robotic telescopes,together with VSNET and AAVSO observers,was essential for identifying TCP J07222683+6220548 as an AM CVn system and triggering confirmation spectroscopy with the 2.5 m CMO SAI telescope.Some outbursting AM CVn systems lacking such detailed follow-up may remain unrecognized among the newly discovered cataclysmic variable candidates.展开更多
This paper investigates the star formation efficiency(SFE)of blue compact galaxies(BCGs)by analyzing various indicators,including(O II),(H_(α)),infrared emissions,and the 1.4 GHz radio continuum.The assessment of SFE...This paper investigates the star formation efficiency(SFE)of blue compact galaxies(BCGs)by analyzing various indicators,including(O II),(H_(α)),infrared emissions,and the 1.4 GHz radio continuum.The assessment of SFE was conducted using publicly accessible data that concentrated on star formation rates(SFRs)and depletion timescales.By employing the fundamental equation,I determined the SFE in relation to its freefall time,which highlighted variations in efficiencies associated with SFR masses derived from different spectra.The results demonstrated that the highest efficiency value was observed in the analysis of the 1.4 GHz radio continuum,emphasizing the importance of studying star-forming clouds across a range of electromagnetic wavelengths to achieve a comprehensive understanding of star formation mechanisms.The study's findings indicated a peak efficiency of star formation value of approximately 0.9%,while the relative minimum obtained from(O II)was around 0.42%,aligning with the range of SFEs documented in the existing literature.Additionally,investigating the factors that influence the variability in efficiency when examining clouds in BCGs across different wave bands is crucial for deepening our comprehension of the underlying processes of star formation.展开更多
Wireless sensor network deployment optimization is a classic NP-hard problem and a popular topic in academic research.However,the current research on wireless sensor network deployment problems uses overly simplistic ...Wireless sensor network deployment optimization is a classic NP-hard problem and a popular topic in academic research.However,the current research on wireless sensor network deployment problems uses overly simplistic models,and there is a significant gap between the research results and actual wireless sensor networks.Some scholars have now modeled data fusion networks to make them more suitable for practical applications.This paper will explore the deployment problem of a stochastic data fusion wireless sensor network(SDFWSN),a model that reflects the randomness of environmental monitoring and uses data fusion techniques widely used in actual sensor networks for information collection.The deployment problem of SDFWSN is modeled as a multi-objective optimization problem.The network life cycle,spatiotemporal coverage,detection rate,and false alarm rate of SDFWSN are used as optimization objectives to optimize the deployment of network nodes.This paper proposes an enhanced multi-objective mongoose optimization algorithm(EMODMOA)to solve the deployment problem of SDFWSN.First,to overcome the shortcomings of the DMOA algorithm,such as its low convergence and tendency to get stuck in a local optimum,an encircling and hunting strategy is introduced into the original algorithm to propose the EDMOA algorithm.The EDMOA algorithm is designed as the EMODMOA algorithm by selecting reference points using the K-Nearest Neighbor(KNN)algorithm.To verify the effectiveness of the proposed algorithm,the EMODMOA algorithm was tested at CEC 2020 and achieved good results.In the SDFWSN deployment problem,the algorithm was compared with the Non-dominated Sorting Genetic Algorithm II(NSGAII),Multiple Objective Particle Swarm Optimization(MOPSO),Multi-Objective Evolutionary Algorithm based on Decomposition(MOEA/D),and Multi-Objective Grey Wolf Optimizer(MOGWO).By comparing and analyzing the performance evaluation metrics and optimization results of the objective functions of the multi-objective algorithms,the algorithm outperforms the other algorithms in the SDFWSN deployment results.To better demonstrate the superiority of the algorithm,simulations of diverse test cases were also performed,and good results were obtained.展开更多
We determined HI parameters for eleven nearby late-type dwarf galaxies using FASHI data cubes,despite the fact that the first version of the FAS HI catalog does not list any radio sources that could correspond to thes...We determined HI parameters for eleven nearby late-type dwarf galaxies using FASHI data cubes,despite the fact that the first version of the FAS HI catalog does not list any radio sources that could correspond to these galaxies.Four of them are probable peripheral satellites of the bright spiral galaxies:NGC 3556,NGC 4258,NGC 4274 and NGC 4490,while others are isolated objects.The considered sample has the following median parameters:a heliocentric velocity of V_(h)=542 km s^(-1),an HI-line width of W_(50)=28 km s^(-1),a hydrogen mass of log(M_(HI)/M_(⊙))=6.83,a stellar mass of log(M_(*)/M_(⊙))=7.19,and a specific star formation rate of sSFR=-10.17 yr^(-1).展开更多
This study examines the properties of standard cold dark matter(CDM),fuzzy dark matter(FDM),and selfinteracting dark matter(SIDM)haloes by analyzing the rotation curves of selected dwarf galaxies from SPARC and LITTLE...This study examines the properties of standard cold dark matter(CDM),fuzzy dark matter(FDM),and selfinteracting dark matter(SIDM)haloes by analyzing the rotation curves of selected dwarf galaxies from SPARC and LITTLE THINGS in 3D catalogs.Utilizing the Markov Chain Monte Carlo(MCMC)method for model fitting and Bayesian Information Criterion for model comparison,we find that compared to CDM,both FDM and SIDM haloes generally provide better fits to the observed rotation curves.Our findings reveal that the concentration–mass relation derived from the dark matter-only simulations is not followed by concentrations or masses obtained from the rotation curve data.Our analysis highlights a positive correlation between the core sizes of FDM and SIDM haloes and the effective radius of the galaxy,attributable to gravitational couplings between baryonic and dark matter components.Moreover,our exploration of dark matter fractions at characteristic radii indicates considerable diversity in dark matter distributions across dwarf galaxies.Notably,FDM and SIDM exhibit greater diversity than CDM in this respect.展开更多
Novae are found to have GeV to TeVγ-ray emission,which reveals the shock acceleration from the white dwarfs.Recently,V1405 Cas was reported to radiate suspiciousγ-ray by Fermi-LAT with low signi?cance(4.1σ)after th...Novae are found to have GeV to TeVγ-ray emission,which reveals the shock acceleration from the white dwarfs.Recently,V1405 Cas was reported to radiate suspiciousγ-ray by Fermi-LAT with low signi?cance(4.1σ)after the optical maximum.Radio observations reveal that it is one of the?ve brightest novae surrounded by low-density ionized gas columns.Here we report a continuous search for GeVγ-ray from Fermi-LAT.Noγ-ray was found.For V1405 Cas the?ux level is lower than other well-studied Fermi novae,and theγ-ray maximum appears at t0+145 days.γ-ray of V1405 Cas is used to search potentialγ-ray periodicity.Noγ-ray periodicity was found during the time of observation.By comparing multi-wavelength data,theγ-ray upper limit to optical?ux ratio with a value at around 10^(-4)is obtained to constrain the shock acceleration.Long-term analysis from Swift-XRT gets X-ray spectral in the post-shock phase,which indicates that V1405 Cas became a super-soft source.The best-?t black body temperature at the super soft state is 0.11-0.19 keV.展开更多
The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white...The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white dwarfs(CONe WDs)when they grow in mass to approach the Chandrasekhar mass limit by accreting matter from a binary main-sequence(MS)companion.In this work,we combine the results of detailed binary evolution calculations with population synthesis models to investigate the rates and delay times of SNe Ia in the CONe WD+MS channel at a low metallicity environment of Z=0.0001.For a constant star formation rate of 5M_(⊙)yr^(−1),our calculations predict that the SN Ia rates in the CONe WD+MS channel at low metallicity of Z=0.0001 is about 0.11−3.89×10^(−4) yr^(−1).In addition,delay times in this channel cover a wide range of 0.05−2.5 Gyr.We further compare our results to those given by a previous study for the CONe WD+MS channel with a higher metallicity of Z=0.02 to explore the influence of metallicity on the results.We find that these two metallicity environments give a slight difference in rates and delay times of SNe Ia from the CONe WD+MS channel,although SNe Ia produced at a low metallicity environment of Z=0.0001 have relatively longer delay times.展开更多
White dwarfs(WDs)are the final stage for most low and intermediate mass stars,which play an important role in understanding stellar evolution and galactic history.Here we performed an asteroseismological analysis on T...White dwarfs(WDs)are the final stage for most low and intermediate mass stars,which play an important role in understanding stellar evolution and galactic history.Here we performed an asteroseismological analysis on TIC 231277791 based on 10 independent modes reported by Romero et al.Two groups of modes were identified with frequency splitting:mode identification_1 with one l=1,m=0 mode,two l=2,m=0 modes,and three l=1 or 2,m=0 modes,and mode identification_2 with one l=1,m=0 mode,three l=2,m=0 modes,and one l=1 or 2,m=0 mode.The rotation period is derived to be 41.64±2.73 hr for TIC 231277791.We established a large sample(7,558,272)of DAV star models using the White Dwarf Evolution Code(WDEC;2018,v16),resulting of optimal models with model_1(mode identification_1):M_(*)=0.570±0.005 M⊙,Teff=11300±10 K,-log(MH/M_(*))=9.15±0.01,-log(M_(He)/M_(*))=4.94±0.01,andσrms=0.06 s,and model_2(mode identification_2):M_(*)=0.720±0.005 M⊙,Teff=1910±10 K,-log(M_(H)/M_(*))=6.11±0.01,-log(M_(He)/M_(*))=3.09±0.01,andσrms=0.04 s.The central oxygen abundances are 0.71(optimal model_1)and 0.72(optimal model_2),respectively,which are consistent with the results of stellar structure and evolution theory.展开更多
Type Ia supernovae(SNe Ia)are among the most extreme phenomena in the Universe and play a crucial role in the studies of stellar evolution,galactic chemical evolution and cosmology.However,the progenitors of SNe Ia ar...Type Ia supernovae(SNe Ia)are among the most extreme phenomena in the Universe and play a crucial role in the studies of stellar evolution,galactic chemical evolution and cosmology.However,the progenitors of SNe Ia are still under debate.It has been suggested that SNe Ia could be produced by helium(He)novae in the singledegenerate channel.Recently,a He nova named[HP99]159 was proposed to be a progenitor candidate for SNe Ia,in which the white dwarf(WD)has a mass of 1.2_(0.4)^(+0.18)M_(⊙),the He star’s mass ranges from 0.8M_(⊙)to 2.0M_(⊙)and the orbital period was suggested to be 2.33 or 1.16 days.In the present work,we evolved a large number of primordial binaries to the formation of WD+He star systems and investigated their future evolution.We provided a representative evolutionary track of[HP99]159 and found that[HP99]159 may originate from a primordial binary with a 6.16M_(⊙)primary and a 4.32M_(⊙)secondary with an initial orbital period of 5110 days.We also found that[HP99]159 might evolve to an SN Ia explosion as suggested by previous studies,or it may also form an accretion-induced collapse event or a wide double WD.Further detailed observations are needed in future studies to provide more information about the precise nature of[HP99]159.展开更多
I suggest the double-degenerate(DD)scenario with a merger-to-explosion delay(MED)time(the DD-MED scenario)of about 1-2 yr to explain the rare properties of the recently analyzed typeⅠa supernova(SN Ia)SN2020aeuh.The ...I suggest the double-degenerate(DD)scenario with a merger-to-explosion delay(MED)time(the DD-MED scenario)of about 1-2 yr to explain the rare properties of the recently analyzed typeⅠa supernova(SN Ia)SN2020aeuh.The rare properties are the SNⅠa ejecta interacting with a carbon-oxygen(CO)-rich circumstellar material(CSM)at approximately 50 days post-explosion.In this DD-MED scenario,two massive CO white dwarfs(WDs),with masses of M_(1)■1.1M_(☉)and M_(2)■M_(☉),merge to leave a rapidly rotating lonely WD of about the Chandrasekhar mass.The merger process ejects M_(CSM)■0.7M_(☉)to form a nonspherical CO-rich CSM.At the explosion,there is a lonely WD and a detached hydrogen-and helium-deficient CSM.Studies proposed the other lonely WD scenario,the core-degenerate(CD)scenario,to explain several specific SNe Ia and SN Ia remnants.SN 2020aeuh is the first particular SN Ia that is attributed to the DD-MED scenario.Besides being slightly brighter than typical SNe Ia and the CSM interaction,SN 2020aeuh is a normal SN Ia.Therefore,this study strengthens the claim of earlier studies,which are based on other arguments,like the properties of SN Ia remnants,that the lonely WD scenarios,i.e.,the DD-MED and CD scenarios,might account for most,if not all,normal SNe Ia.These earlier studies also argue that all SN Ia scenarios,whether lonely WD or not,might contribute to peculiar SNe Ia.展开更多
With joint analysis based on the parents, F 1, F 2 and backcrosses, the authors found that the resistance of the maize inbred line Huangzaosi to the maize dwarf mosaic virus strain B was conditioned by a major gene ...With joint analysis based on the parents, F 1, F 2 and backcrosses, the authors found that the resistance of the maize inbred line Huangzaosi to the maize dwarf mosaic virus strain B was conditioned by a major gene and polygene, and identified a new major gene. Bulked segregate and microsatellite analysis of a F 2 progeny from the combination of Huangzaosi×Mo17 were used to identify the resistance gene, mdm1(t), on the long arm of chromosome 6. This new resistance gene is tightly linked to and located between the microsatellite markers loci, phi077 and bnlg391. The linkage distances between phi077-mdm1(t) and mdm1(t)-bnlg391 are 4.74 centiMorgan (cM) and 6.72 cM respectively.展开更多
Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lod...Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lodging resistance and a greater harvest index, allowing for the increased use of nitrogen fertilizer. Dwarf breeding had made a great breakthrough in the rice breeding. The breeding and extension of excellent dwarf varieties remarkably improved the yield potential of rice. Therefore, the plant height is still one of the focuses in rice genetic research.展开更多
文摘With the advancement of astronomical observation technology,people have a deeper understanding of the formation and evolution of galaxies,but many details of our own Milky Way and other external galaxies are still unknown.Therefore,by studying the formation and orbital transformation mechanism of satellites,planets and stars,the author puts forward a new theory on the formation and evolution of stars and galaxies,thus revealing the hierarchical structure of galaxies and the formation and evolution laws of main sequence stars,red giants,white dwarfs,black dwarfs,supernovae,neutron stars,black holes and quasars.Some special phenomena in the course of star formation and evolution,such as sunspots,flares,fast radio bursts and gamma-ray bursts,have also been revealed.
基金funded by the National Key Research and Development Plan of China(2023YFD1400300)National Natural Science Foundation of China(U23A6006,32270149,32272555)+1 种基金Zhejiang Provincial Natural Science Foundation(LZ22C140001)the Ningbo Major Research and Development Plan Project(2023Z124).
文摘Viruses are significant pathogens causing severe plant infections and crop losses globally.The resistance mechanisms of rice to viral diseases,particularly Southern rice black-streaked dwarf virus(SRBSDV),remain poorly understood.In this study,we assessed SRBSDV susceptibility in 20 Xian/indica(XI)and 20 Geng/japonica(GJ)rice varieties.XI-1B accessions in the Xian subgroup displayed higher resistance than GJ accessions.Comparative transcriptome analysis revealed changes in processes like oxidoreductase activity,jasmonic acid(JA)metabolism,and stress response.JA sensitivity assays further linked antiviral defense to the JA pathway.These findings highlight a JA-mediated resistance mechanism in rice and offer insights for breeding SRBSDV-resistant varieties.
基金supported by grants from the National Natural Science Foundation of China(32270290)the Shanghai Engineering Research Center of Plant Germplasm Resources(17DZ2252700).
文摘Plant height is an important trait that affects the crop yield and overall productivity.The Green Revolution,which began in the 1960s,brought about a remarkable surge in grain production,largely credited to the introduction of new wheat(Triticum aestivum)and rice(Oryza sativa)varieties,specifically the dwarf variants.Short plants offer several advantages,including denser planting,resistance to lodging,and easier application of fertilizers or fungicides(Stokstad,2023).
基金supported by the National Natural Science Foundation of China(32241044)Key project at central government level:The ability establishment of sustainable use for valuable Chinese medicine resources(2060302)+2 种基金China Academy of Chinese Medical Sciences Innovation Fund(CI2023E002)Sichuan Province Natural Science Foundation of China(2022NSFSC1688)Guizhou Province Science and Technology Support Program of China(Qiankehezhongyindi[2024]006-1 and Qiankehezhicheng[2022]Yiban 105)。
文摘The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countries.However,the currently planted varieties are all semi-domesticated landraces with delayed flowering and excessive height.These defects limit yield improvement per unit area and mechanized harvesting.In this study,a major QTL associated with flowering time and plant height in adlay has been mapped and identified as Cl CCT,a gene having a conserved function and regulatory pathway for inhibiting flowering time and increasing plant height in gramineous crops.Among the six identified haplotypes of Cl CCT,the haplotype with 38-bp insertion in promoter region of Cl CCT has earlier flowering time and wider geographical distribution than other haplotypes.The insertion variation,which arises from the segmental duplication of Cl CCT,can inhibit the expression level of reporter gene and has been used in breeding for early maturity and dwarfing.These research results not only reinforce our understanding of the importance of CCT domain protein in the tropical crops adapting to high-latitude environment,but also provide a validated breeding target for the early maturity and dwarfing of adlay.
基金support of the Foundation for the Development of Theoretical Physics and Mathematics BASIS(project 24-2-1-6-1)supported by the UKRI Science and Technology Facilities Council and is a collaboration between the University of Edinburgh(grant ST/N002512/1)and Queen’s University Belfast(grant ST/N002520/1)within the LSST:UK Science Consortium+4 种基金supported by the National Science Foundation under grants No.AST-1440341 and AST-2034437primarily funded to search for near earth asteroids through NASA grants NN12AR55G,80NSSC18K0284,and80NSSC18K1575partially funded by Kepler/K2 grant J1944/80NSSC19K0112 and HST GO-15889STFC grants ST/T000198/1 and ST/S006109/1made use of the Astrophysics Data System,funded by NASA under Cooperative Agreement 80NSSC21M00561。
文摘We present the discovery of TCP J07222683+6220548,a new ultracompact binary system of the AM CVn type.This system was first identified displaying aΔV=7.6 mag outburst on 2025-01-20.9416 UTC by the New Milky Way wide-field survey for transients and later independently detected by ASAS-SN and ZTF.The outburst peaked at V_(max)=12.45 and lasted for seven days,followed by a series of rebrightenings.No previous outbursts are found in archival data.Positive superhumps with a period of 0.032546±0.000084 day(46.87±0.12 minutes),barely detectable during the main outburst,became clearly visible during the first rebrightening that lasted from day 18 to day 24 after the initial outburst.No convincing change in the superhump period was detected.Dense time-series photometry follow-up by a pair of 0.5 m INASAN robotic telescopes,together with VSNET and AAVSO observers,was essential for identifying TCP J07222683+6220548 as an AM CVn system and triggering confirmation spectroscopy with the 2.5 m CMO SAI telescope.Some outbursting AM CVn systems lacking such detailed follow-up may remain unrecognized among the newly discovered cataclysmic variable candidates.
文摘This paper investigates the star formation efficiency(SFE)of blue compact galaxies(BCGs)by analyzing various indicators,including(O II),(H_(α)),infrared emissions,and the 1.4 GHz radio continuum.The assessment of SFE was conducted using publicly accessible data that concentrated on star formation rates(SFRs)and depletion timescales.By employing the fundamental equation,I determined the SFE in relation to its freefall time,which highlighted variations in efficiencies associated with SFR masses derived from different spectra.The results demonstrated that the highest efficiency value was observed in the analysis of the 1.4 GHz radio continuum,emphasizing the importance of studying star-forming clouds across a range of electromagnetic wavelengths to achieve a comprehensive understanding of star formation mechanisms.The study's findings indicated a peak efficiency of star formation value of approximately 0.9%,while the relative minimum obtained from(O II)was around 0.42%,aligning with the range of SFEs documented in the existing literature.Additionally,investigating the factors that influence the variability in efficiency when examining clouds in BCGs across different wave bands is crucial for deepening our comprehension of the underlying processes of star formation.
基金supported by the National Natural Science Foundation of China under Grant Nos.U21A20464,62066005Innovation Project of Guangxi Graduate Education under Grant No.YCSW2024313.
文摘Wireless sensor network deployment optimization is a classic NP-hard problem and a popular topic in academic research.However,the current research on wireless sensor network deployment problems uses overly simplistic models,and there is a significant gap between the research results and actual wireless sensor networks.Some scholars have now modeled data fusion networks to make them more suitable for practical applications.This paper will explore the deployment problem of a stochastic data fusion wireless sensor network(SDFWSN),a model that reflects the randomness of environmental monitoring and uses data fusion techniques widely used in actual sensor networks for information collection.The deployment problem of SDFWSN is modeled as a multi-objective optimization problem.The network life cycle,spatiotemporal coverage,detection rate,and false alarm rate of SDFWSN are used as optimization objectives to optimize the deployment of network nodes.This paper proposes an enhanced multi-objective mongoose optimization algorithm(EMODMOA)to solve the deployment problem of SDFWSN.First,to overcome the shortcomings of the DMOA algorithm,such as its low convergence and tendency to get stuck in a local optimum,an encircling and hunting strategy is introduced into the original algorithm to propose the EDMOA algorithm.The EDMOA algorithm is designed as the EMODMOA algorithm by selecting reference points using the K-Nearest Neighbor(KNN)algorithm.To verify the effectiveness of the proposed algorithm,the EMODMOA algorithm was tested at CEC 2020 and achieved good results.In the SDFWSN deployment problem,the algorithm was compared with the Non-dominated Sorting Genetic Algorithm II(NSGAII),Multiple Objective Particle Swarm Optimization(MOPSO),Multi-Objective Evolutionary Algorithm based on Decomposition(MOEA/D),and Multi-Objective Grey Wolf Optimizer(MOGWO).By comparing and analyzing the performance evaluation metrics and optimization results of the objective functions of the multi-objective algorithms,the algorithm outperforms the other algorithms in the SDFWSN deployment results.To better demonstrate the superiority of the algorithm,simulations of diverse test cases were also performed,and good results were obtained.
基金supported by the Russian Science Foundation grant No 24-12-00277。
文摘We determined HI parameters for eleven nearby late-type dwarf galaxies using FASHI data cubes,despite the fact that the first version of the FAS HI catalog does not list any radio sources that could correspond to these galaxies.Four of them are probable peripheral satellites of the bright spiral galaxies:NGC 3556,NGC 4258,NGC 4274 and NGC 4490,while others are isolated objects.The considered sample has the following median parameters:a heliocentric velocity of V_(h)=542 km s^(-1),an HI-line width of W_(50)=28 km s^(-1),a hydrogen mass of log(M_(HI)/M_(⊙))=6.83,a stellar mass of log(M_(*)/M_(⊙))=7.19,and a specific star formation rate of sSFR=-10.17 yr^(-1).
基金financially supporting this research through PPMI KK 2024 Program,contract number 616BO/IT1.C02/KU/2024。
文摘This study examines the properties of standard cold dark matter(CDM),fuzzy dark matter(FDM),and selfinteracting dark matter(SIDM)haloes by analyzing the rotation curves of selected dwarf galaxies from SPARC and LITTLE THINGS in 3D catalogs.Utilizing the Markov Chain Monte Carlo(MCMC)method for model fitting and Bayesian Information Criterion for model comparison,we find that compared to CDM,both FDM and SIDM haloes generally provide better fits to the observed rotation curves.Our findings reveal that the concentration–mass relation derived from the dark matter-only simulations is not followed by concentrations or masses obtained from the rotation curve data.Our analysis highlights a positive correlation between the core sizes of FDM and SIDM haloes and the effective radius of the galaxy,attributable to gravitational couplings between baryonic and dark matter components.Moreover,our exploration of dark matter fractions at characteristic radii indicates considerable diversity in dark matter distributions across dwarf galaxies.Notably,FDM and SIDM exhibit greater diversity than CDM in this respect.
基金supported by the National Natural Science Foundation of China(NSFC,grant No.12393853)the Scientific Research Foundation of Hunan Provincial Education Department(21C0343)+1 种基金the Science Research Project of the University(Youth Project)of the Department of Education of Guizhou Province(QJJ[2022]348)the Science and Technology Foundation of Guizhou Province(QKHJC-ZK[2023]442)。
文摘Novae are found to have GeV to TeVγ-ray emission,which reveals the shock acceleration from the white dwarfs.Recently,V1405 Cas was reported to radiate suspiciousγ-ray by Fermi-LAT with low signi?cance(4.1σ)after the optical maximum.Radio observations reveal that it is one of the?ve brightest novae surrounded by low-density ionized gas columns.Here we report a continuous search for GeVγ-ray from Fermi-LAT.Noγ-ray was found.For V1405 Cas the?ux level is lower than other well-studied Fermi novae,and theγ-ray maximum appears at t0+145 days.γ-ray of V1405 Cas is used to search potentialγ-ray periodicity.Noγ-ray periodicity was found during the time of observation.By comparing multi-wavelength data,theγ-ray upper limit to optical?ux ratio with a value at around 10^(-4)is obtained to constrain the shock acceleration.Long-term analysis from Swift-XRT gets X-ray spectral in the post-shock phase,which indicates that V1405 Cas became a super-soft source.The best-?t black body temperature at the super soft state is 0.11-0.19 keV.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(grant Nos.XDB1160303,XDB1160000)the National Natural Science Foundation of China(NSFC,Nos.12288102,12333008,12090040/1,11873016,11973080,and 11803030)+3 种基金the National Key R&D Program of China(Nos.2021YFA1600403,2021YFA1600401 and 2021YFA1600400)the Chinese Academy of Sciences(CAS),the Yunnan Ten Thousand Talents Plan–Young&Elite Talents Project,and the CAS“Light of West China”Program,the International Centre of Supernovae,Yunnan Key Laboratory(No.202302AN360001)the Yunnan Fundamental Research Projects(grant Nos.202401BC070007,202201BC070003,and 202001AW070007)the“Yunnan Revitalization Talent Support Program”—Science&Technology Champion Project and Yunling Scholar Project(No.202305AB350003).
文摘The nature of progenitors of Type Ia supernovae(SNe Ia)and their explosion mechanism remains unclear.It has been suggested that SNe Ia may have resulted from thermonuclear explosions of hybrid carbon-oxygen-neon white dwarfs(CONe WDs)when they grow in mass to approach the Chandrasekhar mass limit by accreting matter from a binary main-sequence(MS)companion.In this work,we combine the results of detailed binary evolution calculations with population synthesis models to investigate the rates and delay times of SNe Ia in the CONe WD+MS channel at a low metallicity environment of Z=0.0001.For a constant star formation rate of 5M_(⊙)yr^(−1),our calculations predict that the SN Ia rates in the CONe WD+MS channel at low metallicity of Z=0.0001 is about 0.11−3.89×10^(−4) yr^(−1).In addition,delay times in this channel cover a wide range of 0.05−2.5 Gyr.We further compare our results to those given by a previous study for the CONe WD+MS channel with a higher metallicity of Z=0.02 to explore the influence of metallicity on the results.We find that these two metallicity environments give a slight difference in rates and delay times of SNe Ia from the CONe WD+MS channel,although SNe Ia produced at a low metallicity environment of Z=0.0001 have relatively longer delay times.
基金supported by the International Centre of Supernovae,Yunnan Key Laboratory(No.202302AN36000101)supported by the Yunnan Province Youth Talent Project(2019-182)。
文摘White dwarfs(WDs)are the final stage for most low and intermediate mass stars,which play an important role in understanding stellar evolution and galactic history.Here we performed an asteroseismological analysis on TIC 231277791 based on 10 independent modes reported by Romero et al.Two groups of modes were identified with frequency splitting:mode identification_1 with one l=1,m=0 mode,two l=2,m=0 modes,and three l=1 or 2,m=0 modes,and mode identification_2 with one l=1,m=0 mode,three l=2,m=0 modes,and one l=1 or 2,m=0 mode.The rotation period is derived to be 41.64±2.73 hr for TIC 231277791.We established a large sample(7,558,272)of DAV star models using the White Dwarf Evolution Code(WDEC;2018,v16),resulting of optimal models with model_1(mode identification_1):M_(*)=0.570±0.005 M⊙,Teff=11300±10 K,-log(MH/M_(*))=9.15±0.01,-log(M_(He)/M_(*))=4.94±0.01,andσrms=0.06 s,and model_2(mode identification_2):M_(*)=0.720±0.005 M⊙,Teff=1910±10 K,-log(M_(H)/M_(*))=6.11±0.01,-log(M_(He)/M_(*))=3.09±0.01,andσrms=0.04 s.The central oxygen abundances are 0.71(optimal model_1)and 0.72(optimal model_2),respectively,which are consistent with the results of stellar structure and evolution theory.
基金supported by the National Natural Science Foundation of China(NSFC,grant Nos.12288102,12225304,and 12090040/12090043)the National Key R&D Program of China(No.2021YFA1600404)+3 种基金the Western Light Project of CAS(No.XBZG-ZDSYS-202117)the Yunnan Revitalization Talent Support Program(Yunling Scholar Project)the Yunnan Fundamental Research Project(No.202201BC070003)the International Centre of Supernovae,Yunnan Key Laboratory(No.202302AN360001).
文摘Type Ia supernovae(SNe Ia)are among the most extreme phenomena in the Universe and play a crucial role in the studies of stellar evolution,galactic chemical evolution and cosmology.However,the progenitors of SNe Ia are still under debate.It has been suggested that SNe Ia could be produced by helium(He)novae in the singledegenerate channel.Recently,a He nova named[HP99]159 was proposed to be a progenitor candidate for SNe Ia,in which the white dwarf(WD)has a mass of 1.2_(0.4)^(+0.18)M_(⊙),the He star’s mass ranges from 0.8M_(⊙)to 2.0M_(⊙)and the orbital period was suggested to be 2.33 or 1.16 days.In the present work,we evolved a large number of primordial binaries to the formation of WD+He star systems and investigated their future evolution.We provided a representative evolutionary track of[HP99]159 and found that[HP99]159 may originate from a primordial binary with a 6.16M_(⊙)primary and a 4.32M_(⊙)secondary with an initial orbital period of 5110 days.We also found that[HP99]159 might evolve to an SN Ia explosion as suggested by previous studies,or it may also form an accretion-induced collapse event or a wide double WD.Further detailed observations are needed in future studies to provide more information about the precise nature of[HP99]159.
文摘I suggest the double-degenerate(DD)scenario with a merger-to-explosion delay(MED)time(the DD-MED scenario)of about 1-2 yr to explain the rare properties of the recently analyzed typeⅠa supernova(SN Ia)SN2020aeuh.The rare properties are the SNⅠa ejecta interacting with a carbon-oxygen(CO)-rich circumstellar material(CSM)at approximately 50 days post-explosion.In this DD-MED scenario,two massive CO white dwarfs(WDs),with masses of M_(1)■1.1M_(☉)and M_(2)■M_(☉),merge to leave a rapidly rotating lonely WD of about the Chandrasekhar mass.The merger process ejects M_(CSM)■0.7M_(☉)to form a nonspherical CO-rich CSM.At the explosion,there is a lonely WD and a detached hydrogen-and helium-deficient CSM.Studies proposed the other lonely WD scenario,the core-degenerate(CD)scenario,to explain several specific SNe Ia and SN Ia remnants.SN 2020aeuh is the first particular SN Ia that is attributed to the DD-MED scenario.Besides being slightly brighter than typical SNe Ia and the CSM interaction,SN 2020aeuh is a normal SN Ia.Therefore,this study strengthens the claim of earlier studies,which are based on other arguments,like the properties of SN Ia remnants,that the lonely WD scenarios,i.e.,the DD-MED and CD scenarios,might account for most,if not all,normal SNe Ia.These earlier studies also argue that all SN Ia scenarios,whether lonely WD or not,might contribute to peculiar SNe Ia.
文摘With joint analysis based on the parents, F 1, F 2 and backcrosses, the authors found that the resistance of the maize inbred line Huangzaosi to the maize dwarf mosaic virus strain B was conditioned by a major gene and polygene, and identified a new major gene. Bulked segregate and microsatellite analysis of a F 2 progeny from the combination of Huangzaosi×Mo17 were used to identify the resistance gene, mdm1(t), on the long arm of chromosome 6. This new resistance gene is tightly linked to and located between the microsatellite markers loci, phi077 and bnlg391. The linkage distances between phi077-mdm1(t) and mdm1(t)-bnlg391 are 4.74 centiMorgan (cM) and 6.72 cM respectively.
文摘Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lodging resistance and a greater harvest index, allowing for the increased use of nitrogen fertilizer. Dwarf breeding had made a great breakthrough in the rice breeding. The breeding and extension of excellent dwarf varieties remarkably improved the yield potential of rice. Therefore, the plant height is still one of the focuses in rice genetic research.
