Genetically-and environmentally-dependent processes drive interspecific and intraspecific divergence in the Chinese relict endemic genus Dipteronia

China is a hotspot of relict plant species that were once widespread throughout the Northern Hemisphere.Recent research has demonstrated that the occurrence of long-term stable refugia in the mountainous regions of central and south-western China allowed their persistence through the late Neogene climate fluctuations.One of these relict lineages is Dipteronia,an oligotypic tree genus with a fossil record extending to the Paleocene.Here,we investigated the genetic variability,demographic dynamics and diversification patterns of the two currently recognized Dipteronia species(Dipteronia sinensis and D.dyeriana).Molecular data were obtained from 45 populations of Dipteronia by genotyping three cpDNA regions,two single copy nuclear genes and 15 simple sequence repeat loci.The genetic study was combined with niche comparison analyses on the environmental space,ecological niche modeling,and landscape connectivity analysis.We found that the two Dipteronia species have highly diverged both in genetic and ecological terms.Despite the incipient speciation processes that can be observed in D.sinensis,the occurrence of long-term stable refugia and,particularly,a dispersal corridor along Daba Shan-west Qinling,likely ensured its genetic and ecological integrity to date.Our study will not only help us to understand how populations of Dipteronia species responded to the tectonic and climatic changes of the Cenozoic,but also provide insight into how Arcto-Tertiary relict plants in East Asia survived,evolved,and diversified.

ELLIPTIC EQUATIONS IN DIVERGENCE FORM WITH DISCONTINUOUS COEFFICIENTS IN DOMAINS WITH CORNERS

We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across the discontinuity surfaces and provide an example to illustrate the issue regarding the regularity at the corners.

Kullback-Leibler Divergence Based ISAC Constellation and Beamforming Design in the Presence of Clutter

Integrated sensing and communication(ISAC)is regarded as a pivotal technology for 6G communication.In this paper,we employ Kullback-Leibler divergence(KLD)as the unified performance metric for ISAC systems and investigate constellation and beamforming design in the presence of clutters.In particular,the constellation design problem is solved via the successive convex approximation(SCA)technique,and the optimal beamforming in terms of sensing KLD is proven to be equivalent to maximizing the signal-to-interference-plus-noise ratio(SINR)of echo signals.Numerical results demonstrate the tradeoff between sensing and communication performance under different parameter setups.Additionally,the beampattern generated by the proposed algorithm achieves significant clutter suppression and higher SINR of echo signals compared with the conventional scheme.

Intensity Evolution of Zonal Shear Line over the Tibetan Plateau in Summer:A Perspective of Divergent and Rotational Kinetic Energies

Based on the ERA5 reanalysis datasets during 1980-2019,a total of eleven zonal shear lines(ZSLs)that caused heavy precipitation and lasted more than 60 hours over the Tibetan Plateau in summer are selected for composite analysis.By decomposing the kinetic energy(K)near the ZSL into divergent and rotational kinetic energies(K_(D)and K_(R))and the kinetic energy of interaction between the divergent wind and the rotational wind(K_(R)D),the influence of the rotational and divergent winds on the evolution of the ZSL intensity is investigated from the perspective of K_(D)and K_(R).The main results are as follows.The ZSL is a comprehensive reflection of rotation and convergence.The intensity evolution of ZSL is essentially synchronized with those of K,K_(R),and K_(RD)but lags behind K_(D)by about three hours.The enhancement of K is mainly contributed by K_(R),which is governed by the conversion from K_(D)to K_(R).Furthermore,the increase in the conversion from K_(D)to K_(R)is controlled by the geostrophic effect term Af,which is determined by the joint enhancement of the zonal rotational and meridional divergent wind components(u_(R)and v_(D)).Therefore,the joint enhancement of u_(R)and v_(D)controls the increase of the ZSL intensity,leading to increased precipitation.

THE DIVERGENCE-CONVERGENCE EFFECT OF SURFACE CURRENT AND ITS ACTION ON THE BOHAI SEA

The action of the wind field and the influence of topography can cause divergence or convergence of surface current. The existence of the divergence-convergence effect is proved and the dynamical significance of the divergent or convergent state and its link with many marine phenomena are pointed out. Divergence fields of surface current in the Bohai Sea in winter and summer are obtained by numerical modelling describing the divergence-convergence character of seasonally wind-driven current. The relation between the effect and seasonal marine phenomena is discussed. Study on the divergence-convergence effect of surface current (DCESC)can be an indirect method for testing the calculated results.

Tunable 3D Nanofiber Architecture of Polycaprolactone by Divergence Electrospinning for Potential Tissue Engineering Applications

The creation of biomimetic cell environments with micro and nanoscale topographical features resembling native tissues is critical for tissue engineering. To address this challenge, this study focuses on an innovative electrospinning strategy that adopts a symmetrically divergent electric field to induce rapid self-assembly of aligned polycaprolactone(PCL) nanofibers into a centimeter-scale architecture between separately grounded bevels. The 3D microstructures of the nanofiber scaffolds were characterized through a series of sectioning in both vertical and horizontal directions. PCL/collagen(type I)nanofiber scaffolds with different density gradients were incorporated in sodium alginate hydrogels and subjected to elemental analysis. Human fibroblasts were seeded onto the scaffolds and cultured for 7 days. Our studies showed that the inclination angle of the collector had significant effects on nanofiber attributes, including the mean diameter, density gradient, and alignment gradient. The fiber density and alignment at the peripheral area of the 45°-collector decreased by 21% and 55%, respectively, along the z-axis,while those of the 60°-collector decreased by 71% and 60%, respectively. By altering the geometry of the conductive areas on the collecting bevels, polyhedral and cylindrical scaffolds composed of aligned fibers were directly fabricated. By using a four-bevel collector, the nanofibers formed a matrix of microgrids with a density of 11%. The gradient of nitrogen-to-carbon ratio in the scaffold-incorporated hydrogel was consistent with the nanofiber density gradient. The scaffolds provided biophysical stimuli to facilitate cell adhesion, proliferation, and morphogenesis in 3D.

Genetic variability and divergence studies in pod and seed traits of Pongamia pinnata(L.) Pierre., accessions in Bay Islands

In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length （75.51 mm）, pod width （34.62 mm）, pod thickness （17.55 mm）, 100 pod weight （770.33 g）, seed width （21.23 mm）, 100 seed weight （377.00 g）, oil percentage （43.92%） and germination percentage （94.7%）. However, the maximum seed length （26.46 mm） was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 （2.50 and 2.44 respectively）. The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 （for seed length） to 0.95 （pod length） and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance （10.238）shown by cluster VI and the maximum inter cluster distance （17.021） between V and HI followed by III and II （15.942）. Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations.

THE DIVERGENCE OF LAGRANGE INTERPOLATION IN EQUIDISTANT NODES

It is a classical result of Bernstein that the sequence of Lagrange interpolation polynomials to \x\ at e-qually spaced nodes in [-1.1] diverges everywhere. except at zero and the end-points. In this paper we show that the sequence of Lagrange interpolation polynomials corresponding to the functions which possess better smoothness on equidistant nodes in [-1.1] still diverges every -where in the interval except at zero and the end-points.

Gapless genome assembly of azalea and multi-omics investigation into divergence between two species with distinct f lower color

The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color studies.Here,we investigated the divergence between two parental species with different f lower color widely used for azalea breeding.Gapless genome assembly was generated for the yellow-f lowered azalea,Rhododendron molle.Comparative genomics found recent proliferation of long terminal repeat retrotransposons(LTR-RTs),especially Gypsy,has resulted in a 125 Mb(19%)genome size increase in species-specific regions,and a significant amount of dispersed gene duplicates(13402)and pseudogenes(17437).Metabolomic assessment revealed that yellow f lower coloration is attributed to the dynamic changes of carotenoids/f lavonols biosynthesis and chlorophyll degradation.Time-ordered gene co-expression networks(TO-GCNs)and the comparison confirmed the metabolome and uncovered the specific gene regulatory changes underpinning the distinct f lower pigmentation.B3 and ERF TFs were found dominating the gene regulation of carotenoids/f lavonols characterized pigmentation in R.molle,while WRKY,ERF,WD40,C2H2,and NAC TFs collectively regulated the anthocyanins characterized pigmentation in the red-f lowered R simsii.This study employed a multi-omics strategy in disentangling the complex divergence between two important azaleas and provided references for further functional genetics and molecular breeding.

Chloroplast genomic diversity in Bulbophyllum section Macrocaulia(Orchidaceae,Epidendroideae,Malaxideae):Insights into species divergence and adaptive evolution

Bulbophyllum is the largest genus in Orchidaceae with a pan tropical distribution.Due to highly significant diversifications,it is considered to be one of the most taxonomically and phylogenetically complex taxa.The diversification pattern and evolutionary adaptation of chloroplast genomes are poorly understood in this species-rich genus,and suitable molecular markers are necessary for species determination and phylogenetic analysis.A natural Asian section Macrocaulia was selected to estimate the interspecific divergence of chloroplast genomes in this study.Here,we sequenced the complete chloroplast genome of four Bulbophyllum species,including three species from section Macrocaulia.The four chloroplast genomes had a typical quadripartite structure with a genome size ranged from 156,182 to 158,524 bp.The chloroplast genomes included 113 unique genes encoding 79 proteins,30 tRNAs and 4 rRNAs.Comparison of the four chloroplast genomes showed that the three species from section Macrocaulia had similar structure and gene contents,and shared a number of indels,which mainly contribute to its monophyly.In addition,interspecific divergence level was also great.Several exclusive indels and polymorphism SSR loci might be used for taxonomical identification and determining interspecific polymorphisms.A total of 20 intergenic regions and three coding genes of the most variable hotspot regions were proposed as candidate effective molecular markers for future phylogenetic relationships at different taxonomical levels and species divergence in Bulbophyllum.All of chloroplast genes in four Bulbophyllum species were under purifying selection,while 13 sites within six genes exhibited sitespecific selection.A whole chloroplast genome phylogenetic analysis based on Maximum Likelihood,Bayesian and Parsimony methods all supported the monophyly of section Macrocaulia and the genus of Bulbophyllum.Our findings provide valuable molecular markers to use in accurately identifying species,clarifying taxonomy,and resolving the phylogeny and evolution of the genus Bulbophyllum.The molecular markers developed in this study will also contribute to further research of conservation of Bulbophyllum species.

Mechanisms of species divergence through visual adaptation and sexual selection:Perspectives from a cichlid model system

The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences aredirectly linked to ecological traits that are subject to divergent selection. Sensory adaptation can play a major role in this process,because selective mating is often mediated by sexual signals: bright colours, complex song, pheromone blends and so on. Whendivergent sensory adaptation affects the perception of such signals, mating patterns may change as an immediate consequence.Alternatively, mating preferences can diverge as a result of indirect effects: assortative mating may be promoted by selectionagainst intermediate phenotypes that are maladapted to their (sensory) environment. For Lake Victoria cichlids, the visual environmentconstitutes an important selective force that is heterogeneous across geographical and water depth gradients. We investigatethe direct and indirect effects of this heterogeneity on the evolution of female preferences for alternative male nuptial colours(red and blue) in the genus Pundamilia. Here, we review the current evidence for divergent sensory drive in this system, extractgeneral principles, and discuss future perspectives [Current Zoology 56 (3): 285-299, 2010].

Experimental Study on the Effects of Magnetic Field Configuration near the Channel Exit on the Plume Divergence of Hall Thrusters

Experimental investigations into the effects of the magnetic field configuration near the channel exit on the plume of Hall thrusters were conducted. The magnetic field configuration near the channel exit is characterized by the inclination angle between the magnetic field lines and the thruster radial direction. Different inclination angles were obtained by varying the current ratio in the coils. The plume divergence angles were measured by a dual-directed probe. The results showed that the plume divergence angle increased obviously with the increase in the magnitude of the inclination angle near the channel exit. Therefore, in order to optimize the magnetic field for reducing plume divergence, the magnitude of the inclination angle should be reduced as much as possible. It suggests that the magnetic field configuration near the channel exit is another important factor that affects plume divergence.

Duplication and transcriptional divergence of three Kunitz protease inhibitor genes that modulate insect and pathogen defenses in tea plant(Camellia sinensis)

Kunitz protease inhibitors(KPIs)are ubiquitous in plants and act as crucial compounds in defense responses against insect attack and pathogen infection.However,the influence of gene duplication on the postdivergence of the CsKPI genes involved in biotic stresses in tea plant is not well known.Here,we identified three CsKPI genes from tea plant(Camellia sinensis)and characterized their expression and evolutionary patterns among plant species.We found that CsKPI1,CsKPI2,and CsKPI3 diverged from their common ancestor 72.94 million years ago(MYA),and the tandem duplication of CsKPI2 and CsKPI3 occurred 26.78 MYA.An in vitro protein assay showed that the three CsKPI proteins were functional and inhibited the production of p-nitroanilide(PNA)from an artificial substrate.The three CsKPI-GFP fusion proteins localized to the cytoplasm.We showed that salicylic acid(SA)and transcripts of CsKPI2 and CsKPI3 significantly accumulated after infection with Glomerella cingulata.The application of exogenous SA stimulated the high expression of both CsKPI2 and CsKPI3 by activating cis-elements within their promoters.Under Ectropis oblique attack,CsKPI1 expression and jasmonic acid(JA)levels were more abundant in both insect-damaged leaf tissues and undamaged neighboring leaves.The application of jasmonic acid methyl ester elicited high expression levels of CsKPI1,suggesting that CsKPI1 accumulation requires JA production in tea plant.The overall findings suggest that the transcriptional divergence of KPI genes after duplication led to the specialized role of CsKPI1 in the physiological response to insect stress;the functional conservation between CsKPI2 and CsKPI3 confers resistance to pathogen infection in tea plant.

Differential Privacy Preserving Dynamic Data Release Scheme Based on Jensen-Shannon Divergence

Health monitoring data or the data about infectious diseases such as COVID-19 may need to be constantly updated and dynamically released,but they may contain user's sensitive information.Thus,how to preserve the user's privacy before their release is critically important yet challenging.Differential Privacy(DP)is well-known to provide effective privacy protection,and thus the dynamic DP preserving data release was designed to publish a histogram to meet DP guarantee.Unfortunately,this scheme may result in high cumulative errors and lower the data availability.To address this problem,in this paper,we apply Jensen-Shannon(JS)divergence to design the OPTICS(Ordering Points To Identify The Clustering Structure)scheme.It uses JS divergence to measure the difference between the updated data set at the current release time and private data set at the previous release time.By comparing the difference with a threshold,only when the difference is greater than the threshold,can we apply OPTICS to publish DP protected data sets.Our experimental results show that the absolute errors and average relative errors are significantly lower than those existing works.

THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|~α(2<α<4) AT EQUIDISTANT NODES

It is a classical result of Bernstein that the sequence of Lagrange interpolation polumomials to ｜x｜ at equally spaced nodes in [-1, 1] diverges everywhere, except at zero and the end-points. In the present paper, toe prove that the sequence of Lagrange interpolation polynomials corresponding to ｜x｜^α （2 〈 α 〈 4） on equidistant nodes in [-1, 1] diverges everywhere, except at zero and the end-points.

Extensive genetic divergence among Diptychus maculatus populations in northwest China

D. maculates is a kind of specialized Schizothoracinae fish has been locally listed as a protected animal in Xinjiang Province, China. Ill River located in north of Tianshan Mountain and Tarim River located in north of Qinghai-Tibetan Plateau were two main distribution areas of this fish. To investigate the genetic diversity and genetic structure ofD. maculates, four populations from Tarim River system and two populations from Ili River system were collected in this study. A 570-bp sequence of the control region was obtained for 105 specimens. Twenty-four haplotypes were detected from six populations, only Kunes River population and Kashi River population shared haplotypes with each other. For all the populations examined, the haplotype diversity （h） was 0.904 8±0.012 6, nucleotide diversity （n） was 0.027 9±0.013 9, and the average number of pairwise nucleotide differences （k） was 15.878 3±7.139 1. The analysis of molecular variance （AMOVA） showed that 86.31% of the total genetic variation was apportioned among populations, and the variation within sampled populations was 13.69%. Genetic differences among sampled populations were highly significant. Fst statistical test indicated that all populations were significantly divergent from each other （P〈0.01）. The largest Fst value was between Yurungkash River population and Muzat River population, while the smallest fst value was between Kunes River population and Kashi River population. NJ phylogenetic tree of D-loop haplotypes revealed two main clades. The neutrality test and mismatch distribution analysis suggested that the fish had went through a recent population expansion. The uplift of Tianshan Mountain and movement of Qinghai-Tibetan Plateau might contribute to the wide genetic divergence of D. maculates in northwest China.

New Evidence for Improving Omega Estimation by Explicitly Considering Horizontal Divergence

It is well known that the quasi-geostrophic （QG） omega equation with only two contributors respectively associated with vorticity advection （VA） and temperature advection is derived for midlatitude synoptic-scale systems only.Based on reliable reanalysis data,new evidence revealed by cyclonic and anticyclonic cases indicates that forecasters might sometimes experience problems by paying too much attention to the 500-hPa VA when estimating vertical motions not only in subtropical systems but also in systems meeting all the assumptions of the QG omega equation.Our investigations also showed that explicitly considering the vertical profiles of horizontal divergence could allow for better interpretation of vertical motions and weather in these real cases,suggesting that this equation might not be sufficient due to the presence of only two horizontaldivergence-related （HDR） mechanisms and the absence of other HDR mechanisms,e.g.,frictional force,mountain barriers,diabatic/adiabatic processes,and acceleration/deceleration of air flows.

病理心电信号的Jensen-Shannon divergence分析

目的研究快速区分不同病理心电信号的算法是当前临床医学诊断的研究热点之一。方法本文采用基于Jensen-Shannon divergence的复杂度分析方法,从MIT-BIH标准数据库中提取正常窦性心率、房性早搏、窦性心动过缓信号,分别计算它们的复杂度。结果正常心率信号复杂度最高,窦性心动过缓信号次之,房性早搏最低。方差检验结果表明,此方法得出的3种信号的复杂度具有显著性差异。结论病理心电信号的Jensen-Shannon divergence分析对临床医学检测和诊断房性早搏、窦性心动过缓信号有很好的借鉴意义。

Selective footprints and genes relevant to cold adaptation and other phenotypic traits are unscrambled in the genomes of divergently selected chicken breeds

Background The genomes of worldwide poultry breeds divergently selected for performance and other phenotypic traits may also be affected by,and formed due to,past and current admixture events.Adaptation to diverse environments,including acclimation to harsh climatic conditions,has also left selection footprints in breed genomes.Results Using the Chicken 50K_CobbCons SNP chip,we genotyped four divergently selected breeds:two aboriginal,cold tolerant Ushanka and Orloff Mille Fleur,one egg-type Russian White subjected to artificial selection for cold tolerance,and one meat-type White Cornish.Signals of selective sweeps were determined in the studied breeds using three methods:(1)assessment of runs of homozygosity islands,(2)F_(ST) based population differential analysis,and(3)haplotype differentiation analysis.Genomic regions of true selection signatures were identified by two or more methods or in two or more breeds.In these regions,we detected 540 prioritized candidate genes supplemented them with those that occurred in one breed using one statistic and were suggested in other studies.Amongst them,SOX5,ME3,ZNF536,WWP1,RIPK2,OSGIN2,DECR1,TPO,PPARGC1A,BDNF,MSTN,and beta-keratin genes can be especially mentioned as candidates for cold adaptation.Epigenetic factors may be involved in regulating some of these important genes(e.g.,TPO and BDNF).Conclusion Based on a genome-wide scan,our findings can help dissect the genetic architecture underlying various phenotypic traits in chicken breeds.These include genes representing the sine qua non for adaptation to harsh environments.Cold tolerance in acclimated chicken breeds may be developed following one of few specific gene expression mechanisms or more than one overlapping response known in cold-exposed individuals,and this warrants further investigation.

THE DIVERGENCE OF LAGRANGE INTERPOLATION FOR |x|~a

This paper shows that the sequence of Lagrange interpolation polynomials corresponding to the rune tion f（z） =｜x｜^α（1〈α〈2） on [-1,1] can diverge everywhere in the interval except at zero and the end-points.