Multiple plant lineages have independently evolved sex chromosomes and variable karyotypes to maintain their sessile lifestyles through constant biological innovation.Morus notabilis,a dioecious mulberry species,has t...Multiple plant lineages have independently evolved sex chromosomes and variable karyotypes to maintain their sessile lifestyles through constant biological innovation.Morus notabilis,a dioecious mulberry species,has the fewest chromosomes among Morus spp.,but the genetic basis of sex determination and karyotype evolution in this species has not been identified.In this study,three high-quality genome assemblies were generated for Morus spp.[including dioecious M.notabilis(male and female)and Morus yunnanensis(female)]with genome sizes of 301–329 Mb and were grouped into six pseudochromosomes.Using a combination of genomic approaches,we found that the putative ancestral karyotype of Morus species was close to 14 protochromosomes,and that several chromosome fusion events resulted in descending dysploidy(2n=2x=12).We also characterized a~6.2-Mb sex-determining region on chromosome 3.Four potential male-specific genes,a partially duplicated DNA helicase gene(named MSDH)and three Ty3_Gypsy long terminal repeat retrotransposons(named MSTG1/2/3),were identified in the Y-linked area and considered to be strong candidate genes for sex determination or differentiation.Population genomic analysis showed that Guangdong accessions in China were genetically similar to Japanese accessions of mulberry.In addition,genomic areas containing selective sweeps that distinguish domesticated mulberry from wild populations in terms of flowering and disease resistance were identified.Our study provides an important genetic resource for sex identification research and molecular breeding in mulberry.展开更多
Based on the numerical evidences,an analytical expression of the Dirichletto-Neumann mapping in the form of infinite product was first conjectured for the onedimensional characteristic Schrodinger equation with a sinu...Based on the numerical evidences,an analytical expression of the Dirichletto-Neumann mapping in the form of infinite product was first conjectured for the onedimensional characteristic Schrodinger equation with a sinusoidal potential in[Commun.Comput.Phys.,3(3):641-658,2008].It was later extended for the general secondorder characteristic elliptic equations with symmetric periodic coefficients in[J.Comp.Phys.,227:6877-6894,2008].In this paper,we present a proof for this Dirichlet-toNeumann mapping.展开更多
The conflict of laws of Hong Kong has predominately preserved traditional common law rules of pre-England conflict of laws. It is considered as the legal basis of the harmonization of law conflicts between different l...The conflict of laws of Hong Kong has predominately preserved traditional common law rules of pre-England conflict of laws. It is considered as the legal basis of the harmonization of law conflicts between different legal units, which mainly include three parts： jurisdiction, choice of law, judicial assistance in civil and commercial matters. As far as the legal source of the conflict of laws of Hong Kong is concerned, convention is an important part of international law sources. Currently, there are ten special conventions related to private international law; one of which is the New York Convention on the Recognition and Enforcement of Arbitral Awards, and the other nine are the conventions consulted by the Hague Conference on Private International Law （＂HCCH＂）, including the Statute of the Hague Conference. Also, there exist non-special conventions relating to private international law, which play an important role in Hong Kong. These conventions have brought tremendous benefits to Hong Kong. More attention needs to be paid to the conventions of private international law to assist Hong Kong in cooperation with other more jurisdictions.展开更多
基金supported by the National Key R&D Program of China(Grant No.2019YFD1000604)the China Agriculture Research System(Grant No.CARS-18-ZJ0201)+1 种基金the Forestry Promotion by Science and Technology Program of Chongqing,China(Grant No.Yulinkeyan2020-2)the Sichuan Science and Technology Program,China(Grant No.22NSFSC3680).
文摘Multiple plant lineages have independently evolved sex chromosomes and variable karyotypes to maintain their sessile lifestyles through constant biological innovation.Morus notabilis,a dioecious mulberry species,has the fewest chromosomes among Morus spp.,but the genetic basis of sex determination and karyotype evolution in this species has not been identified.In this study,three high-quality genome assemblies were generated for Morus spp.[including dioecious M.notabilis(male and female)and Morus yunnanensis(female)]with genome sizes of 301–329 Mb and were grouped into six pseudochromosomes.Using a combination of genomic approaches,we found that the putative ancestral karyotype of Morus species was close to 14 protochromosomes,and that several chromosome fusion events resulted in descending dysploidy(2n=2x=12).We also characterized a~6.2-Mb sex-determining region on chromosome 3.Four potential male-specific genes,a partially duplicated DNA helicase gene(named MSDH)and three Ty3_Gypsy long terminal repeat retrotransposons(named MSTG1/2/3),were identified in the Y-linked area and considered to be strong candidate genes for sex determination or differentiation.Population genomic analysis showed that Guangdong accessions in China were genetically similar to Japanese accessions of mulberry.In addition,genomic areas containing selective sweeps that distinguish domesticated mulberry from wild populations in terms of flowering and disease resistance were identified.Our study provides an important genetic resource for sex identification research and molecular breeding in mulberry.
基金The authors would like to thank Prof.Matthias Ehrhardt for the inspiring discussion on this work.C.Zheng was supported by the National Natural Science Foundation of China under Grant No.11371218.
文摘Based on the numerical evidences,an analytical expression of the Dirichletto-Neumann mapping in the form of infinite product was first conjectured for the onedimensional characteristic Schrodinger equation with a sinusoidal potential in[Commun.Comput.Phys.,3(3):641-658,2008].It was later extended for the general secondorder characteristic elliptic equations with symmetric periodic coefficients in[J.Comp.Phys.,227:6877-6894,2008].In this paper,we present a proof for this Dirichlet-toNeumann mapping.
文摘The conflict of laws of Hong Kong has predominately preserved traditional common law rules of pre-England conflict of laws. It is considered as the legal basis of the harmonization of law conflicts between different legal units, which mainly include three parts： jurisdiction, choice of law, judicial assistance in civil and commercial matters. As far as the legal source of the conflict of laws of Hong Kong is concerned, convention is an important part of international law sources. Currently, there are ten special conventions related to private international law; one of which is the New York Convention on the Recognition and Enforcement of Arbitral Awards, and the other nine are the conventions consulted by the Hague Conference on Private International Law （＂HCCH＂）, including the Statute of the Hague Conference. Also, there exist non-special conventions relating to private international law, which play an important role in Hong Kong. These conventions have brought tremendous benefits to Hong Kong. More attention needs to be paid to the conventions of private international law to assist Hong Kong in cooperation with other more jurisdictions.
