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China Communications 2024年第2期21卷 17-31页

作者： Shaojing Wang xiaomei Tang Jing Lei Chunjiang Ma Chao Wen Guangfu sun School of Electronic Science National University of Defense TechnologyChangsha 410073China

Orthogonal Time Frequency and Space(OTFS) modulation is expected to provide high-speed and ultra-reliable communications for emerging mobile applications, including low-orbit satellite communications. Using the Doppler frequency for positioning is a promising research direction on communication and navigation integration. To tackle the high Doppler frequency and low signal-to-noise ratio(SNR) in satellite communication, this paper proposes a Red and Blue Frequency Shift Discriminator(RBFSD) based on the pseudo-noise(PN) sequence.The paper derives that the cross-correlation function on the Doppler domain exhibits the characteristic of a Sinc function. Therefore, it applies modulation onto the Delay-Doppler domain using PN sequence and adjusts Doppler frequency estimation by red-shifting or blue-shifting. Simulation results show that the performance of Doppler frequency estimation is close to the Cramér-Rao Lower Bound when the SNR is greater than -15dB. The proposed algorithm is about 1/D times less complex than the existing PN pilot sequence algorithm, where D is the resolution of the fractional Doppler.

关键词： channel estimation communication and navigation integration Orthogonal Time Frequency and Space pseudo-noise sequence red-blue frequency shift discriminator

Infl uence of altitude and tree class on climate-growth relationships in a larch plantation in subtropical China

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林业研究:英文版 2023年第6期34卷 1869-1880页

作者： Chunyan Wu Dongsheng Chen xiaomei sun Shougong Zhang State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China

Precise quantifi cation of climate-growth relationships can make a major contribution to scientifi c forest management.However,whether diff erences in the response of growth to climate at diff erent altitudes remains unclear.To answer this,264 trees of Larix kaempferi from 88 plots,representing diff erent altitudinal ranges(1000-2100 m)and tree classes were sampled and used to develop tree-ring chronologies.Tree-ring growth(TRG)was either positively(dominant)or negatively(intermediate and suppressed)correlated with climate in diff erent tree classes at diff erent altitudes.TRG was strongly correlated with growing season at low altitudes,but was less sensitive to climate at middle altitudes.It was mainly limited by precipitation and was highly sensitive to climate at low altitudes.Climate-growth relationships at high altitudes were opposite compared to those at low altitudes.TRG of dominant trees was more sensitive to climate change compared to intermediate and suppressed trees.Climate factors(annual temperatures;moisture,the number of frost-free days)had diff erent eff ects on tree-ring growth of diff erent tree classes along altitudinal gradients.It was concluded that the increase in summer temperatures decreased water availability,resulting in a signifi cant decline in growth rates after 2005 at lower altitudes.L.kaempferi is suitable for planting in middle altitudes and dominant trees were the best sampling choice for accurately assessing climate-growth relationships.

关键词： Tree-ring width index Chronology Correlation coeffi cient Additive mixed models Tree classes

Altitude shape genetic and phenotypic variations in growth curve parameters of Larix kaempferi

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Journal of Forestry Research 2023年第2期34卷 507-517页

作者： Yalin Zhang Leiming Dong Yunhui Xie Dongsheng Chen xiaomei sun Research Institute of Forestry Chinese Academy of ForestryBeijing 100091People’s Republic of China State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of State Forestry and Grassland AdministrationBeijing 100091People’s Republic of China Beijing Floriculture Engineering Technology Research Centre Beijing Botanical GardensBeijing 100084People’s Republic of China

To study the effects of geoclimatic variables of provenances on growth phenotypes and selected plus provenances,over 3000 trees of 22-year-old Larix kaempferi were evaluated from trials established in two climate zones for provenance selection and to explore the influence of climate variables on provenance performance.The material was replicated plantings of 84 open pollinated families from six provenances distributed in the mountains of central Japan.Provenance variation was observed in most age groups and the heritability of growth traits showed large differences.The phenotypic maximum value of height and diameter were significantly positive with altitude,and mean annual precipitation being important factors.Diameter at breast height growth was significantly negative with altitude and spring rainfall.The Ina provenance of relatively high altitudes,was well adapted to a variety of climates.Altitude might be the driving force for phenotypic and genetic variations and local adaptation.

关键词： Larix kaempferi Breeding Altitude Genetic parameters

Insights into spin polarization regulated exciton dissociation and charge separation of C_(3)N_(4)for efficient hydrogen evolution and simultaneous benzylamine oxidation

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Nano Research 2023年第7期16卷 8845-8852页

作者： Gen Li xiaomei sun Peng Chen Meiyang Song Tianxiang Zhao Fei Liu Shuang-Feng Yin Provincial Guizhou Key Laboratory of Green Chemical and Clean Energy Technology School of Chemistry and Chemical EngineeringGuizhou UniversityGuiyang 550025China College of Chemistry and Chemical Engineering Advanced Catalytic Engineering Research Center of the Ministry of EducationState Key Laboratory of Chemo/Biosensing and ChemometricsHunan UniversityChangsha 410082China

The employment of spin polarization under an external magnetic field holds great potential for the improvements of photocatalytic performance.However,owing to the huge difference in dielectric properties between ferromagnetic oxide and polymers,the photogenerated excitons with spin states are often limited to the ferromagnetic oxide wells,which leads to unsatisfactory activity.In this paper,a single-atom Co-doped C_(3)N_(4)photocatalyst is successfully synthesized for photocatalytic water splitting and simultaneous oxidation of benzylamine.Under a tiny external magnetic field(24.5 mT),the hydrogen production rate could reach at 3979.0μmol·g^(-1)·h^(-1),which is about 340 times that of C_(3)N_(4).Experimental results and theoretical calculations indicate that the interaction of Co d and N p orbital changes the symmetry center of C_(3)N_(4),resulting in an increase in dielectric constant and spin polarization.Moreover,magnetic fields further promote parallel electron spin,and the increased number of charges with the parallel spin-down state is likely to dissociate under the action of an external magnetic field.On the other hand,the Co-N bond provides a huge built-in electric field and active site for strengthening the charge transfer and surface reaction.This work not only deepens the understanding of spin polarization,but also enriches methods to accelerate electron-hole separation.

关键词： low magnetic field C_(3)N_(4) spin polarization photocatalytic hydrogen evolution benzylamine oxidation

Mating patterns and pollen dispersal in a Japanese larch(Larix kaempferi) clonal seed orchard： a case study

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Science China(Life Sciences) 2018年第9期61卷 1011-1023页

作者： Xingbin Chen xiaomei sun Leiming Dong Shougong Zhang State Key Laboratory of Tree Genetics and Breeding Chinese Academy of ForestryBeijing100091China Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Research Institute of Forestry Chinese Academy of ForestryBeijing 100091China Jiangxi Provincial Key Lab for Plant Biotechnology Jiangxi Academy of ForestryBeijing 100091 China

Pollination dynamics highly determines the genetic quality of seed orchard crops. However, there is less research about the effect of mating patterns on seed productivity of orchard crops. So far, clonal seed orchards have been producing genetically improved seedlings used for most Japanese larch(Larix kaempferi(Lamb.) Carr.) plantations in China. In the present study, a total of 17 highly variable simple sequence repeat(SSR) markers were used for genotyping a progeny trial population consisting of 647 open-pollinated progenies germinated from seeds which were collected from 63 maternal clones with 140 potential paternal clones in a Japanese larch clonal seed orchard in China. Paternity analysis was used in the present case study in order to evaluate the level of paternal gametic contribution, estimate pollen contamination and selfing rates, and investigate pollination patterns,pollen dispersal patterns and the impact of mating patterns on seed productivity of orchard crops. We observed 93.7% of the success rate of the parental assignment, unequal paternal gametic contribution(0–12.4%) with 6.3% of the progenies derived from pollen contamination or unsampled pollen donors, and absence of evidence for selfing. We also found that pollination rate highly depended on the distance between pollen donors and maternal parents, the majority of the identified crossing(65.7%)occurred between clones within a 150-m radius, and large variations in growth performance existed among the paternal halfsiblings. Progeny growth performance(diameter at breast(DBH) and height(HGT)) was measured at Age-20 in order to investigate the impact of mating patterns on timber production of orchard crops. As either the paternal or maternal, two clones(i.e., clones Z38 and Z62) were identified to have produced progenies with higher average stem volume breeding values than that of all of the progenies. Specifically, the genetic gains for volume were 3.53% for the two clones as paternal parents, and 8.26% as the maternal parents at Age-20. Thus, bo

关键词：日本落叶松种子发芽花粉污染交配模式果园细胞案例生长性能

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构建租购并举的退役军人住房保障体系研究

社会保障评论 2024年第3期8卷 26-37页

作者：朱亚鹏孙小梅中山大学公共管理研究中心中山大学政治与公共事务管理学院

适宜的居住环境对于保障和维护退役军人合法权益、促进社会稳定等具有重要意义。在新时代背景下,退役军人住房保障如何既满足国防和军队建设需要、又不超越基本国情是亟待破解的重要命题。本文在辨析国内外退役军人社会保障的理论基础之... 详细信息

适宜的居住环境对于保障和维护退役军人合法权益、促进社会稳定等具有重要意义。在新时代背景下,退役军人住房保障如何既满足国防和军队建设需要、又不超越基本国情是亟待破解的重要命题。本文在辨析国内外退役军人社会保障的理论基础之上,从历史制度主义视角梳理了我国退役军人住房保障政策演进,分析了现有政策的主要特征与关键问题,最终提出了构建租购并举的退役军人住房保障体系的政策建议。研究对于推动广大退役军人“住有所居”与“住有宜居”、构建“普惠与优待”叠加的退役军人政策制度体系具有启示意义。

关键词：退役军人住房保障租购并举政策体系

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Frontiers of Agricultural Science and Engineering 2017年第4期4卷 482-492页

作者： Chao sun Meng LAI Shougong ZHANG xiaomei sun Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Research Institute of ForestryChinese Academy of Forestry State Key Laboratory of Tree Genetics and Breeding Chinese Academy of Forestry Key Laboratory of Silviculture Co-Innovation Center of Jiangxi Typical Trees Cultivation and UtilizationCollege of Forestry Jiangxi Agricultural University

Wood properties are important traits that determine quality of structural wood. With the aim of performing efficient early selection for wood properties we investigated genetic variation in 20 Larix kaempferi clones aged from 4 to 15 years for four quality traits: wood density, wall thickness to lumen area, microfibrillar angle(MFA) and modulus of elasticity(MOE). We observed that age-related trends in overall means varied for differen traits: MFA decreased with the age, while the others generally increased with the age. Phenotypic variance always showed significant differences from the age of 8 years onward, with CVG ranging from 4% to 25%. Also clonal repeatability increased steadily until 9 years old and then kept medium or higher intensity(0.4–0.8). After the age of 6, genetic correlations were generally higher than phenotypic correlations. Estimates of early selection efficiency suggested that the optimal selection age for wood density was at age 5–6 years, while it was 9–10 years for the other traits. In combination with previous results we proposed a comprehensive early selection strategy for larch clonal breeding that involved selection based on nursery rooting ability, phenology, growth traits, and wood properties.

关键词： early selection genetic variation wood properties Silvi Scan Larix kaempferi

Optimization of Factors Influencing Adventitious Rooting in Hybrid Larch

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Phyton-International Journal of Experimental Botany 2021年第2期90卷 583-593页

作者： Kuipeng Li Hua Han Yunhui Xie xiaomei sun State Key Laboratory of Tree Genetics and Breeding Key Laboratory of Tree Breeding and Cultivation of State Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing100091China Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation&Key Laboratory of Central South Fast-Growing Timber Cultivation of Forestry Ministry of China Guangxi Forestry Research InstituteNanning530002China

Optimization of in vitro adventitious root induction contributes to the development of a large-scale production system of hybrid clone seedlings of larch(Larix spp.).We used orthogonal testing to investigate the factors that affect the rooting of hybrid larch shoots-activated carbon,vitamin B1,sucrose,glycine,glutamic acid(Glu),cysteine,pH,and induction time in the dark and indole-3-butyric acid(IBA).Variance analysis showed that the effects of sucrose concentration on rooting rate,survival rate,and average root number,pH on the average number of roots;and Glu on survival rate were all significant(p<0.05)when compared to the mock treatments.Among all of the 45 treatments,the highest rooting rate was 90%,the highest survival rate was 100%,and the highest average root number was 11.8.The theoretically optimal procedure of in vitro root induction of hybrid larch shoots is shoot induction on L9 modified medium(pH 6.7)containing 2 mg.L^(-1)naphthalene acetic acid,0.25 mg.L^(-1)IBA,1/3 macroelements,7.5 g.L^(-1)sucrose,and 5 mg.L^(-1)Glu for 8 days,and then root induction on L9 modified medium without auxin.

关键词： Hybrid larch adventitious root orthogonal test variance analysis

Species richness loss after nutrient addition as affected by N:C ratios and phytohormone GA_(3)contents in an alpine meadow community

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Journal of Plant Ecology 2016年第2期9卷 201-211页

作者： xiaomei sun Kailiang Yu Herman HShugart Gang Wang State Key Laboratory of Grassland Agro-Ecosystem School of Life SciencesLanzhou University222 Tianshui RoadChengguan DistrictLanzhouGansu 730000China Department of Environmental Sciences University of Virginia291 McCormick RoadCharlottesvilleVA 22904USA

Aims From the light-competition hypothesis,competition for light is asymmetric and the observed increases in plant-size variability with increasingly denser canopies are primarily due to competition for light.Greater plant height provides pre-emptive access to light and produces increased height differences among species.The question is what produces these differences in plant height or height growth response among species in response to fertilization.Methods In 2009,a field experiment of N,P and N+P enrichments at three levels each was initiated in an alpine meadow on the northeast Qinghai-Tibet Plateau.Effects of fertilization on species richness,aboveground net primary production(ANPP),relative light intensity and plant height of different plant functional groups were determined.Festuca ovina(grass),Kobresia humilis(sedge),Oxytropis ochrocephala(legume),Taraxacum lugubre(rosette forb)and Geranium pylzowianum(upright forb)were selected as exemplars of each of the indicated functional groups.The N:C ratios in aboveground biomass,gibberellic acid(GA_(3))concentrations in leaves,plant heights and height relative growth rate(RGR)of these exemplar species were analyzed in detail.Important Findings Species richness of grasses significantly increased with increasing N+P levels.Species richness of legumes and upright forbs decreased after N and N+P additions.P addition had no significant effect on species richness.The effects of N+P addition on species richness and ANPP were consistently stronger than those of the single N or P fertilization.Reductions in species richness caused by nutrient addition paralleled the increases in ANPP and decreases in light intensity under the canopies,indicating indirect effect of nutrient addition on species richness via ANPP-induced light competition.The exemplar species that responded most positively to fertilization in height and RGR also displayed stronger increases in their GA_(3) content and N:C ratios.GA_(3) concentrations and N:C ratios were positively correlated with height RGR

关键词： nutrient addition N:C ratio GA3 content asymmetry in plant heights competition for light species richness loss

Isolation,expression and single nucleotide polymorphisms(SNPs) analysis of LACCASE gene(LkLAC8) from Japanese larch(Larix kaempferi)

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Journal of Forestry Research 2017年第5期28卷 891-902页

作者： Changyong Liu Yunhui Xie Min Yi Shougong Zhang xiaomei sun State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of Forestry Research Institute of Forestry Chinese Academy of Forestry State Academy of Forestry Administration School of Gardening and Landscape Design Jiangxi Agricultural University

Nucleotide diversity (pi) and linkage disequilibrium (LD) analysis based on SNP marker could provide a sound basis for choosing an association analysis method. Japanese larch (Larix kaempferi) is an important timber coniferous tree species for pulping and papermaking, but its high lignin content has significantly restricted it application potential. In this study, the LACCASE gene, that plays an important regulatory role for lignin biosynthesis, was selected as research target. The full-length cDNA and genomic sequences of the encoding LkLAC8 gene were isolated from the LACCASE expressed sequence tags of the Japanese larch transcriptome database using the rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The cDNA was determined to be 1940 bp, with an open reading frame (ORF, 1734 bp) that encoded a protein of 577 AA. This protein contains four highly specific Cu2+ binding sites and 11 glycosylation sites, thus belonging to the LACCASE family. The deduced protein sequence shared an 89% identity with the PtaLAC from Pinus taeda. A real-time PCR analysis showed that the LkLAC8 transcript was expressed predominantly in mature xylem, with moderate levels in the immature xylem, cambium and mature leaves, the lowest in the roots. Lastly, the genomic sequences of LkLAC8 in 40 individuals from six naturally distributed populations of Japanese larch were amplified, and a total of 201 SNPs (103 and 98 mutation types of transition and transversion, respectively) were detected; the frequency of the SNPs was 1/19 bp. Nucleotide diversity among the six populations ranged from 0.0034 to 0.0053, which suggested that there were no significant differences among the populations. The LD analysis showed that the LD level decayed rapidly within the increasing length of the LkLAC8 gene. These results implied that LD mapping and association analysis based on candidate gene may be feasible for the marker-assisted breeding of new germplasms with low lignin in Japanese larch.

关键词： Gene cloning LACCASE Larix kaempferi Linkage disequilibrium Real-time PCR Single nucleotide polymorphisms