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Local PoincaréSymmetry in Gauge Theory of Gravity

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Communications in Theoretical Physics 2009年第5期51卷 843-844页

作者： ma jian-feng ma Yong-Ge Department of Physics Beijing Normal University Beijing 100875 China

It is well known that the Poincaré gauge theories of gravity do not have the structure of a standard gauge theory. Nevertheless, we show that a general form of action for the gravitational gauge fields in the gauge t... 详细信息

关键词： Poincaré gauge theory translation invariance Lorentz invariance

Transport of cadmium from soil to grain in cereal crops: A review

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Pedosphere 2021年第1期31卷 3-10页

作者： jian feng ma Ren Fang SHEN Ji feng SHAO Institute o f Plant Science and Resources Okayama UniversityChuo 2-20-1Kurashiki 710-0046Japan State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China State Key Laboratory of Subtropical Silviculture Zhejiang A&F UniversityLin'An 311300China

Due to rapid urbanization and industrialization, many soils for crop production are contaminated by cadmium(Cd), a heavy metal highly toxic to many organisms. Cereal crops such as rice, wheat, maize, and barley are the primary dietary source of Cd for humans, and reducing Cd transfer from soil to their grains is therefore an important issue for food safety. During the last decade, great progress has been made in elucidating the molecular mechanisms of Cd transport, particularly in rice. Inter-and intraspecific variations in Cd accumulation have been observed in cereal crops. Transporters for Cd have been identified in rice and other cereal crops using genotypic differences in Cd accumulation and mutant approaches. These transporters belong to different transporter families and are involved in the uptake, vacuolar sequestration, root-to-shoot translocation, and distribution of Cd. Attempts have been made to reduce Cd accumulation in grains by manipulating these transporters through overexpression or knockout of the transporter genes, as well as through marker-assisted selection breeding based on genotypic differences in Cd accumulation in the grains. In this review, we describe recent progress on molecular mechanisms of Cd accumulation in cereal crops and compare different molecular strategies for minimizing Cd accumulation in grains.

关键词： barley gene knockout gene overexpression genotypic difference maize rice transporter wheat

Knockout of a gene encoding a Gγ protein boosts alkaline tolerance in cereal crops

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aBIOTECH 2023年第2期4卷 180-183页

作者： Peitong Wang jian feng ma Institute of Plant Science and Resources Okayama UniversityChuo 2-20-1Kurashiki710-0046Japan

Sorghum is highly tolerant to alkaline stress,but the underlying mechanisms are not well ***,based on genotypic difference in alkaline tolerance of sorghum,it was found that AT1(Alkaline tolerance 1)encoding a G protein is involved in alkaline tolerance through negatively modulating the phosphorylation level of PIP2,an aquaporin with transport activity for H_(2)O_(2).Knockout of AT1 releases its inhibition of PIP2,thereby resulting in an increased transport of H_(2)O_(2)from the cytosol into the apoplast,subsequently boosting alkaline tolerance.

关键词： Alkaline stress Sorghum H_(2)O_(2) Aquaporin G protein

Plant Nutrition for Human Nutrition:Hints from Rice Research and Future Perspectives

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Molecular Plant 2020年第6期13卷 825-835页

作者： Sheng Huang Peitong Wang Naoki Yamaji jian feng ma Institute of Plant Science and Resources Okayama UniversityChuo 2-20-1Kurashiki 710-0046Japan

Both plants and humans require mineral elements for their healthy growth and *** elements in the soil are taken up by the plant roots and transported to the edible parts for human consumption through various different *** ideal future crop for human health should be rich in essential mineral elements but with less toxic elements in the edible ***,due to the great difference in the numbers and amounts of mineral elements required between plants and humans,it is a challenge to balance plant growth and nutrient requirement for *** this article,we mainly focus on the transport system of mineral elements from soil to grain in rice,a staple food for half of the world's population,and discuss recent progress on the underlying genetic and physiological *** are given for silicon,zinc,and iron essential/beneficial for both plants and humans,selenium and iodine only essential for humans,and toxic cadmium and arsenic for all *** of some transporters for these elements,especially those localized in the node for allocation of mineral elements to the grain,has been successful in generating rice with higher density and bioavailability of essential elements but with less accumulation of toxic *** provide our perspectives toward breeding future crops for human health.

关键词： plant nutrition human health mineral elements transporter rice biofortification

Relationship Between Differential Interference Angle and Parameter of Experiment in Molecular Beam

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Communications in Theoretical Physics 2006年第2X期46卷 294-296页

作者： LI Yong-Qing LI jian ma feng-Cai Department of Physics Liaoning University Shenyang 110036 China

Collisional quantum interference （CQI） was observed in the intramolecular rotational energy transfer in the experiment of the static cell, and the integral interference angles were measured. To observe more precise information, the experiment in the molecular beam should be taken,from which the relationship between the differential interference angle and the scattering angle can be obtained. In this paper, the theoretical model of CQI is described in an atom-diatom system in the condition of the molecular beam, based on the first-Born approximation of time-dependent perturbation theory, taking into accounts the long-range interaction potential. The method of observing and measuring correctly the differential interference angle is presented. The changing tendency of the differential interference angle with the impact parameter and relative velocity is discussed. The changing tendencies of the differential interference angle with the parameter of experiment in the molecular beam, including the impact parameter and the velocity are discussed. This theoretical model is important to understand or perform the experiment in the molecular beam.

关键词： differential interference angle quantum interference rotational energy transfer

Elastic Buckling of Bionic Cylindrical Shells Based on Bamboo

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Journal of Bionic Engineering 2008年第3期5卷 231-238页

作者： jian-feng ma Wu-yi Chen Ling Zhao Da-hai Zhao School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing 100083 P. R. China Shenyang Aircraft Design Institute Shenyang 110035 P. R. China

High load-bearing efficiency is one of the advantages of biological structures after the evolution of billions of years. Biomimicking from nature may offer the potential for lightweight design. In the viewpoint ofrnechanics properties, the culm of bamboo comprises of two types of cells and the number of the vascular bundles takes a gradient of distribution. A three-point bending test was carried out to measure the elastic modulus. Results show that the elastic modulus of bamboo decreases gradually from the periphery towards the centre. Based on the structural characteristics of bamboo, a bionic cylindrical structure was designed to mimic the gradient distribution of vascular bundles and parenchyma cells. The buckling resistance of the bionic structure was compared with that of a traditional shell of equal mass under axial pressure by finite element simulations. Results show that the load-bearing capacity of bionic shell is increased by 124.8%. The buckling mode of bionic structure is global buckling while that of the conventional shell is local buckling.

关键词： bionic design bamboo culm thin-walled cylindrical structure buckling load-carrying efficiency

Vascular Cambium-Localized AtSPDT Mediates Xylem-to-Phloem Transfer of Phosphorus for Its Preferential Distribution in Arabidopsis

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Molecular Plant 2020年第1期13卷 99-111页

作者： Guangda Ding Gui Jie Lei Naoki Yamaji Kengo Yokosho Namiki Mitani-Ueno Sheng Huang jian feng ma institute of Plant Science and Resources Okayama UniversityChuo 2-20-1KurashikiJapan College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China

During plant growth and development mineral elements are preferentially delivered to different organs and tissues to meet the differential demand. It has been shown that the preferential distribution of mineral nutrients in gramineous plants is mediated by node-based transporters, but the mechanisms of preferential distribution in dicots are poorly understood. Here, we report a distinct mechanism for the preferential distribution of phosphorus (P) in Arabidopsis plants, revealed by detailed functional analysis of AtSPDT/AtSULTR3;4 (SULTR-like P Distribution Transporter), a homolog of rice OsSPDT. Like OsSPDT, AtSPDT is localized at the plasma membrane and showed proton-dependent transport activity for P. Interestingly, we found that AtSPDT is mainly expressed in the rosette basal region and leaf petiole, and its expression is up-regulated by P deficiency. Tissue-specific analysis showed that AtSPDT is mainly located in the vascular cambium of different organs, as well as in the parenchyma tissues of both xylem and phloem regions. Knockout of AtSPDT inhibited the growth of new leaves under low P due to decreased P distribution to those organs. The seed yields of the wild-type and atspdt mutant plants are similar, but the seeds of mutant plants contain – less P. These results indicate that AtSPDT localized in the vascular cambium is involved in preferential distribution of P to the developing tissues, through xylem-to-phloem transfer mainly at the rosette basal region and leaf petiole.

关键词： A rabidopsis thaliana phosphate transporter SPDT phosphorus distribution vascular cambium

The ferroxidases LPR1 and LPR2 control iron translocation in the xylem of Arabidopsis plants

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Molecular Plant 2022年第12期15卷 1962-1975页

作者： Zhong-Rui Xu Mei-Ling Cai Ying Yang Ting-Ting You jian feng ma Peng Wang Fang-Jie Zhao State Key Laboratory of Crop Genetics and Germplasm Enhancement College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Institute of Plant Science and Resources Okayama UniversityChuo 2-20-1Kurashiki 710-0046Japan Academy for Advanced Interdisciplinary Studies Nanjing Agricultural UniversityNanjing 210095China

Iron(Fe)deficiency is common in agricultural crops and affects millions of people *** of Fe in the xylem is a key step for Fe distribution in *** mechanism controlling this process remains largely ***,we report that two Arabidopsis ferroxidases,LPR1 and LPR2,play a crucial and redundant role in controlling Fe translocation in the ***1 and LPR2 are mainly localized in the cell walls of xylem vessels and the surrounding cells in roots,leaves,and *** of both LPR1 and LPR2 increased the proportion of Fe(II)in the xylem sap,and caused Fe deposition along the vascular bundles especially in the petioles and main veins of leaves,which was alleviated by blocking blue *** lpr1 lpr2 double mutant displayed constitutive expression of Fe deficiency response genes and overaccumulation of Fe in the roots and mature leaves under Fe-sufficient supply,but Fe deficiency chlorosis in the new leaves and inflorescences under low Fe ***,the lpr1 lpr2 double mutant showed lower Fe concentrations in the xylem and phloem saps,and impaired 57Fe translocation along the *** vitro assays showed that Fe(III)-citrate,the main form of Fe in xylem sap,is easily photoreduced to Fe(II)-citrate,which is unstable and prone to adsorption by cell *** together,these results indicate that LPR1 and LPR2 are required to oxidize Fe(II)and maintain Fe(III)-citrate stability and mobility during xylem translocation against *** study not only uncovers an essential physiological role of LPR1 and LPR2 but also reveals a new mechanism by which plants maintain Fe mobility during long-distance translocation in the xylem.

关键词： iron xylem translocation ferroxidases LPR1 LPR2 iron redox

Level of proinsulin in association with cardiovascular risk factors and sleep snoring

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World Journal of Gastroenterology 2005年第32期11卷 5047-5052页

作者： En-Zhi Jia Zhi-jian Yang Shi-Wei Chen Guang-Yao Qi Chun-Fa You jian-feng ma Jing-Xin Zhang Zhen-Zhen Wang Wei-Chong Qian Hai-Yan Wang Wen-Zhu ma Department of Cardiovascular Medicine The First Affiliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu Province China The Disease Control Center of Pizhou City Pizhou 221300 Jiangsu Province China Department of Central Clinical Laboratory The First Affiliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu Province China Department of Nuclear Medicine The First Affiliated Hospital of Nanjing Medical University Nanjing 210029 Jiangsu Province China

AIM: To explore the relationship between the level of proinsulin with cardiovascular risk factors and sleep ***: Based on the random stratified sampling principle, 1 193 Chinese residents in Pizhou City, jiangsu Province (530 males and 663 females, aged 35-59 years with an average age of 46.69 years) were recruited. Their sleep snoring habits were investigated. Biotin-avidin based double mabs ELISA was used to detect specific insulin and proinsulin, and a risk factor score was established to evaluate the individuals according to the number of their risk ***: The results of Spearman correlation analysis and covariate ANOVA analysis after age and sex were controlled, indicated that not only the level of proinsulin (r = 0.156, P = 0.000, F= 5.980 P = 0.000), but also cardiovascular risk factors score (r = 0.194, P = 0.000,F= 11.135, P = 0.000) significantly associated with the frequency of sleep snoring, and the significant relationship between true insulin and frequency of sleep snoring was only shown in the covariate ANOVA analysis (F = 2.868,P = 0.022). The result of multivariate stepwise logistic regression after age, sex, body mass index, waist circumference and true insulin were controlled showed that proinsulin (division by interval of quartile) was an independent risk factor for sleep snoring (OR = 1.220,95%CI: 1.085-1.373, P = 0.001).CONCLUSION: The interaction of cardiovascular risk factors clustering, high proinsulin level and sleep breathing disorder may be a syndrome, which has not been recognized in human beings so far.

关键词： True insulin Proinsulin Snoring Epidemiology