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n-exact Categories Arising from n-exangulated Categories

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数学学报:英文版 2023年第9期39卷 1781-1794页

作者： Jian He Pan Yue Zhou Department of Applied Mathematics Lanzhou University of TechnologyLanzhou730050P.R.China School of Mathematics and Statistics Changsha University of Science and TechnologyChangsha410114P.R.China

Let l be a Krull-Schmidt n-exangulated category and A be an n-extension closed subcategory of l.Then A inherits the n-exangulated structure from the given n-exangulated category in a natural way.This construction gives n-exangulated categories which are neither n-exact categories in the sense of Jasso nor(n+2)-angulated categories in the sense of Geiss-Keller-Oppermann in general.Furthermore,we also give a sufficient condition on when an n-exangulated category A is an n-exact category.These results generalize work by Klapproth and Zhou.

关键词： (n+2)-angulated categories n-exact categories n-extension closed subcategories n-exangulated categories

Causal associations between inflammatory bowel disease and anxiety:A bidirectional Mendelian randomization study

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World Journal of Gastroenterology 2023年第44期29卷 5872-5881页

作者： Ying he Chun-Lan Chen Jian He Si-De Liu Department of Gastroenterology Nanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Infectious Diseases The Second Xiangya Hospital of Central South UniversityChangsha 410011Hunan ProvinceChina Department of Pulmonary and Critical Care Medicine Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou 510080Guangdong ProvinceChina

BACKGROUND Anxiety is common in patients with inflammatory bowel disease(IBD),including those with ulcerative colitis(UC)and Crohn’s disease(CD);however,the causal relationship between IBD and anxiety remains unknown.AIM To investigate the causal relationship between IBD and anxiety by using bidirectional Mendelian randomization analysis.METHODS Single nucleotide polymorphisms retrieved from genome-wide association studies(GWAS)of the European population were identified as genetic instrument variants.GWAS statistics for individuals with UC(6968 patients and 20464 controls;adults)and CD(5956 patients and 14927 controls;adults)were obtained from the International IBD Genetics Consortium.GWAS statistics for individuals with anxiety were obtained from the Psychiatric Genomics Consortium(2565 patients and 14745 controls;adults)and FinnGen project(20992 patients and 197800 controls;adults),respectively.Inverse-variance weighted was applied to assess the causal relationship,and the results were strengthened by heterogeneity,pleiotropy and leave-one-out analyses.RESULTS Genetic susceptibility to UC was associated with an increased risk of anxiety[odds ratio:1.071(95%confidence interval:1.009-1.135),P=0.023],while genetic susceptibility to CD was not associated with anxiety.Genetic susceptibility to anxiety was not associated with UC or CD.No heterogeneity or pleiotropy was observed,and the leave-one-out analysis excluded the potential influence of a particular variant.CONCLUSION This study revealed that genetic susceptibility to UC was significantly associated with anxiety and highlighted the importance of early screening for anxiety in patients with UC.

关键词： Inflammatory bowel disease Anxiety Causal effect Mendelian randomization Genome-wide association studies

APPLICATION OF The FACTORIZATION METHOD TO RECOVER CUTS WITH OBLIQUE DERIVATIVE BOUNDARY CONDITION

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Journal of Computational Mathematics 2022年第3期40卷 373-395页

作者： Jun Guo Jian He Jin Li School of Mathematics and Statistics South-Central University For NationalitiesWuhanChina Department of Basic Courses Air Force Early Warning AcademyWuhanChina School of Science Jiujiang UniversityJiujiangChina

Direct and inverse problems for the scattering of cracks with mixed oblique derivative boundary conditions from the incident plane wave are considered,which describe the scattering phenomenons such as the scattering of tidal waves by spits or reefs.The solvability of the direct scattering problem is proven by using the boundary integral equation method.In order to show the equivalent boundary integral system is Fredholm of index zero,some relationships concerning the tangential potential operator is used.Due to the mixed oblique derivative boundary conditions,we cannot employ the factorization method in a usual manner to reconstruct the cracks.An alternative technique is used in the theoretical analysis such that the far field operator can be factorized in an appropriate form and fulfills the range identity theorem.Finally,we present some numerical examples to demonstrate the feasibility and effectiveness of the factorization method.

关键词： Direct and inverse scattering Oblique derivative Crack The factorization method

Effects of laser shock processing onθ-Al_(2)O_(3)toα-Al_(2)O_(3)transformation and oxide scale morphology evolution in(γ'+β)two-phase Ni-34Al-0.1Dy alloys

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Journal of Materials Science & Technology 2022年第14期109卷 157-166页

作者： Bangyang Zhou Jian He Qijie Zhou Hongbo Guo School of Materials Science and Engineering Beihang University(BUAA)Beijing 100191China Research Institute for Frontier Science Beihang University(BUAA)Beijing 100191China Key Laboratory of High-Temperature Structural Materials&Coatings Technology(Ministry of Industry and Information Technology) Beihang University(BUAA)Beijing 100191China

(γ’+β)two-phase Ni-Al is a promising high-temperature protective coating material used on Ni-base superalloys since it has good interfacial compatibility with superalloys due to the low Al content compared to single-phaseβ-NiA l.In this paper,we aim to improve the oxidation resistance,whereby Ni-34Al-0.1Dy,a(γ’+β)two-phase Ni-Al alloy,was treated by laser shock processing(LSP)and the oxidation behavior at 1150℃ was investigated.The results showed that after oxidation,Al_(2)O_(3)scale formed on the originalβphase of the untreated alloy with a small grain size(200-800 nm),while for the LSP-treated samples,the scale grown on the originalβphase was dominantly composed of larger Al_(2)O_(3)grains with a size of 2-3μm.The distinction was attributed to the promotion ofθ-Al_(2)O_(3)toα-Al_(2)O_(3)transformation induced by the LSP,because the dislocation density,as well as surface roughness,were increased during LSP treatment which can provide heterogeneous nucleation sites forα-Al_(2)O_(3).In addition,the larger-size Al_(2)O_(3)particles,derived from the direct conversion of needle-likeθ-Al_(2)O_(3)in the initial oxidation stage,could rapidly overspread the wholeβphase surface thus reducing the scale growth rate.

关键词： Intermetallics Laser shock processing Oxidation θ-Al_(2)O_(3)toα-Al_(2)O_(3)transformation Morphology evolution

Impact of Si addition on high-temperature oxidation behavior of NiAlHf alloys

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Journal of Materials Science & Technology 2019年第9期35卷 2038-2047页

作者： JingJing Jian He Hongbo Guo School of Materials Science and Engineering Beihang University (BUM)Beijing 100191China Frontier Research Institute of Innovative Science and Technology Beihang University (BUM)Beijing 100191China Key Laboratory of High-temperature Structural Materials & Coatings Technology (Ministry o f Industry and Information Technology) Beihang University (BUM)Beijing 100191China

Silicon (Si) and reactive elements (REs) like hafnium (Hf) have favorable effects on improving the high-temperature oxidation resistance. To reveal the interaction effect between them, Si with different contents was added into P-NiAlHf alloy in this study. Cyclic oxidation behavior at 1200℃ was investigated. Results show that Si can increase the Hf-rich precipitates and suppress Hf outward diffusion, thus inhibit the RE effect leading to worse oxidation resistance. However, NiAlHf-5Si alloy exhibited a lower oxidation rate and better spallation resistance mainly because of the existence of micro-cracks and Ni2 Al3 phases which provided more rapid diffusion paths for Al^3+.

关键词： Intermetallic NiAl Rare earth element Thermal cycling Oxidation Segregation

Chromatin-remodeling complexes:Conserved and plant-specific subunits in Arabidopsis

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Journal of Integrative Plant Biology 2022年第2期64卷 499-515页

作者： Ji-Yun Shang Xin-Jian He National Institute of Biological Sciences Beijing102206 China Tsinghua Institute of Multidisciplinary Biomedical Research Tsinghua UniversityBeijing100084 China

Adenosine triphosphate-dependent chromatin remodeling complexes are important for the regulation of transcription,DNA replication,and genome stability in eukaryotes.Although genetic studies have illustrated various biological functions of core and accessory subunits of chromatin-remodeling complexes in plants,the identification and characterization of chromatin-remodeling complexes in plants is lagging behind that in yeast and animals.Recent studies determined whether and how the Arabidopsis SWI/SNF,ISWI,INO80,SWR1,and CHD chromatin remodelers function in multi-subunit complexes in Arabidopsis.Both conserved and plant-specific subunits of chromatin-remodeling complexes have been identified and characterized.These findings provide a basis for further studies of the molecular mechanisms by which the chromatinremodeling complexes function in plants.

关键词： ATPase chromatin remodeling complex INO80 ISWI SWI/SNF SWR1 transcription

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen jian-Jun he Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early universe.Among these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent reactions.To date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational precision.In this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium abundance.We found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H uncertainty.Currently,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he rate.From the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Gravitational Equivalence Theorem and Double-Copy for Kaluza-Klein Graviton Scattering Amplitudes

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Research 2022年第4期2022卷 411-420页

作者： Yan-Feng Hang Hong-Jian He Tsung-Dao Lee Institute and School of Physics and Astronomy Key Laboratory for Particle Astrophysics and Cosmology(MOE)Shanghai Key Laboratory for Particle Physics and CosmologyShanghai Jiao Tong UniversityShanghaiChina Institute of Modern Physics and Department of Physics Tsinghua UniversityBeijingChina Center for High Energy Physics Peking UniversityBeijingChina

We analyze the structure of scattering amplitudes of the Kaluza-Klein (KK) gravitons and of the KK gravitational Goldstone bosons in the compactified 5d general relativity (GR). Using a general Rξ gauge fixing, we study the geometric Higgs mechanism for the massive spin-2 KK gravitons. We newly propose and prove a gravitational equivalence theorem (GRET) to connect the scattering amplitudes of longitudinal KK gravitons to that of the KK gravitational Goldstone bosons, which formulates the geometric gravitational Higgs mechanism at the scatteringS-matrix level. We demonstrate that the GRET provides a general energy cancellation mechanism guaranteeing the N-point longitudinal KK graviton scattering amplitudes to have their leading energy dependence cancelled down by a large power factor of E^(2N)(N≥4) up to any loop level. We propose an improved double-copy approach to construct the massive KK graviton (Goldstone) amplitudes from the KK gauge boson (Goldstone) amplitudes. With these, we establish a new correspondence between the two types of energy cancellations in the four-point longitudinal KK amplitudes at tree level: E^(4)→E0 in the KK gauge theory and E^(10)→E^(2) in the KK GR theory.

关键词： theory gauge guarantee

Abscisic acid-dependent PMT1 expression regulates salt tolerance by alleviating abscisic acid-mediated reactive oxygen species production in Arabidopsis

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Journal of Integrative Plant Biology 2022年第9期64卷 1803-1820页

作者： Qi Yu he jian Feng Jin he Qiang Lou Feng Feng Dang Ji Ming Xu Shao jian Zheng jian Li Yang State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou310058 China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityHangzhou311300 China State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources South China Agricultural UniversityGuangzhou510642 China

Phosphocholine(PCho)is an intermediate metabolite of nonplastid plant membranes that is essential for salt tolerance.However,how PCho metabolism modulates response to salt stress remains unknown.here,we characterize the role of phosphoethanolamine N-methyltransferase 1(PMT1)in salt stress tolerance in Arabidopsis thaliana using a T-DNA insertional mutant,geneediting alleles,and complemented lines.The pmt1 mutants showed a severe inhibition of root elongation when exposed to salt stress,but exogenous ChoCl or lecithin rescued this defect.pmt1 also displayed altered glycerolipid metabolism under salt stress,suggesting that glycerolipids contribute to salt tolerance.Moreover,pmt1 mutants exhibited altered reactive oxygen species(ROS)accumulation and distribution,reduced cell division activity,and disturbed auxin distribution in the primary root compared with wild-type seedlings.We show that PMT1 expression is induced by salt stress and relies on the abscisic acid(ABA)signaling pathway,as this induction was abolished in the aba2-1 and pyl112458 mutants.However,ABA aggravated the salt sensitivity of the pmt1 mutants by perturbing ROS distribution in the root tip.Taken together,we propose that PMT1 is an important phosphoethanolamine N-methyltransferase participating in root development of primary root elongation under salt stress conditions by balancing ROS production and distribution through ABA signaling.

关键词： abscisic acid(ABA) oxidative stress plasma membrane phosphoethanolamine N-methyltransferase phospholipid metabolism salt stress